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switch puzzle answer (spoiler)
Jason Striegel
I would have simply guessed all prisoners will refuse to go. Therefore none will ever have gone. All have visited the same amount.
You're very close... only problem is that when the 'counter' goes into the room... switch A could have RANDOMLY been in the ON position. He would count a person, but no one actually switched it on.
Michael H. Pryor
Yeah you did have the right idea but you should have every prison go through twice so that if the first ON position was random there is a double check.
Michael Lee King II
The solution to the problem is as follows:
Michael D. Kersey
Consider the scenario:
How about each prisoner leaves their left shoe in the switch room. When someone counts 22 shoes, all prisoners have visited the room... :P
The switches form 4-state space:
Peter Radkov
P.S. The Counter makes the 2-3 transition with non-zero probability.
Peter Radkov
Nicely done!
Jason Striegel
David Neary came up with a good solution
David Clayworth
Initially, I had an idea similar to the "leave the left shoe off" idea--upon each prisoner's initial visit to the cell, he makes a mark (e.g. by scuffing his shoe on the wall). When *any* prisoner counts 24 marks on the wall, he can be confident that *all* the prisoners have visited the cell, regardless of the state of the switches.
My solution is this.
Thirumal Azhagan V.T
It is not the OLD position, but the NEW position.
Thirumal Azhagan V.T
If we assume that the person who goes there for the first time knows that he is the first person, then there will be no problem with Initial position of switch A. Because, if the first prisoner sees the initial position as on, then he switches B. It is in on position, so the counter gets the message. Otherwise, the first prisoner switches A to on.
This is a terrific puzzle. Probably too hard to give in an interview (it took me three bike rides to figure out) but really fun.
Ole Eichhorn
If this discussion is still active,then i came across a solution for this problem at this page.
Arun Iyer
Arun -
Ole Eichhorn
Fog Creek Home


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Pac-12 Roundup: Arizona State faces Wisconsin and its long tradition of strong tailbacks
A look around the Pac-12 Conference Friday:
Arizona State — Wisconsin running game a tradition like few others in college football. Has had eight straight years with a 1,000-yard rusher and three currently average at least 100 yards a game.
Arizona — Kicker Jake Smith will observe Yon Kippur then play against Texas-San Antonio.
USC — Trojans looking forward to Boston College instead of backward to Washington State loss.
UCLA — Nebraska using true freshmen to improve its defense.
Stanford — Army cornerback Chris Carnegie from the mean streets of East Oakland plays the Stanford of his childhood.
California — Golden Bears have lost 18 straight to non-conference top five opponents dating back to 13-0 win over Alabama in 1938 Rose Bowl. Bears are 3-32 against top five teams in conference.
Oregon — Oregonian columnist John Canzano says college coaches — namely Oregon State's Mike Riley — might be wise to see how NFL defenses attack Chip Kelly's Philadelphia Eagles.
Oregon State — Coach Mike Riley knows what UCLA's Jim Mora is going through after death of wide receiver Nick Pasquale.
Washington — "Hothead" safety Sean Parker living up to his "KO" nickname.
Washington State — Safety Damante Horton gone from benched in 2012 to two interceptions versus USC.
Utah — Utes seek to win their first Pac-12 opener. They're 7-11 in league since joining two years ago.

subset: commoncrawl


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Method of laminating and stretching film material and apparatus for said method
A sandwich of plural films of thermoplastic orientable polymers wherein the adjacent surfaces of each adjacent film pair are in direct face-to-face contact while being positively advanced is positively deflected into a temporarily generally uiniform zig-zag or pleated configuration, the deflecting forces being sufficiently strong that the films in the sandwich are cold welded together while being laterally stretched. The deflection into the temporarily pleated configuration can be repeated.
The present invention relates to a method of manufacturing a laminated strength sheet. Cross-laminates of uniaxially oriented films from crystalline polymers are known to exhibit a generally highly advantageous combination of different strength properties of which the most surprising has been the tear propagation strength (of U.S. Pat. No. 3,322,613) especially when a relatively poor bonding is effectuated between the layers. During the tearing from an incision, the layers will then delaminate around the notch while they split or flow in different directions--the tear "forks"--whereby the notch effect is smoothed out. Sheets of this kind are particularly useful for various heavy duty applications such as tarpaulin substitutes, cover sheets, heavy duty bags, and heavy duty wrapping film.
The most expedient method of producing a sheet of the above kind is described in British patent specification No. 816607, and consists in strongly orienting the molecules of a tubular film in its longitudinal direction, helically cutting and unfolding it to a flat film with the orientation at bias (e.g. 45.degree. C.), and subsequently continuously laminating this film with a similarly produced flat film, while the respective directions of orientation are arranged in criss-crossing relationship.
It is known that, for a given thickness, the tear propagation resistance is pronouncedly increased by use of 3 layers with 3 different directions of orientation, e.g. obtained by laminating 1 longitudinally oriented film with 2 films which are oriented at bias as described above.
One drawback of the process described above (and the resultant product) is that it is practically impossible to produce really thin film, whereby the economical advantage of the strength per weight is limited. It has proven that the technical-economical lower limit connected with the carrying out of the spiral-cutting and the laminating processes is, generally speaking, about 30 gr per sq.m. Thus for a 2-layers laminate, the lower limit is about 60 gr per sq.m while for a 3-layers laminate--which as mentioned above is necessary for proper utilization of the tear-stopping effects--it is about 90 gr per sq.m.
A second draw-back is the practical limitation, in width caused by the rotation of heavy machine-parts and bobbins in connection with the spiral cutting. As a very general statement, it can be said that the width is hereby limited to about 11/2-2 m.
A third draw-back relates to certain energy-absorption values for the cross-laminates so produced. Relatively low energy-absorption has been found with regard to high-speed tearing (Elmendorf tear test) and for low and high speed tensile testing (TEA strength and Elmendorf impact strength). In this connection it appears that the very anisotropic character of the layers is disadvantageous. If for instance a 2-ply cross-laminate of this kind is drawn parallel to the direction of orientation in one of the layers, then the yield point and the elongation at break are in essence determined by the layer.
My earlier work to overcome the above-mentioned drawbacks, and to provide for a cheaper production process for a product with similar or analogous properties, is described in British patent specification No. 1261 397. In said specification a process is disclosed which produces a criss-crossing structure through a die with rotating parts, while forming in the same die a soft and weaker middle zone by coextruding. The method consists in coextrusion several concentrical or almost concentrical layers of crystallene polymer alternating with layers of a softer polymer, and dividing said layers inside the die by means of teeth arranged in rows and fixed to the cylindrical die walls pointing inwardly from the concave wall surface and outwardly from the convex wall surface. The die-parts are rotated in opposite directions and thereby the layers are divided according to left-hand helices near one and right-hand helices near the other sheet surface. It is specified that the combing can either be carried through to the middle of the film or be limited to portions near the surfaces. The coextrusion of polymers before the combing zone is adapted to provide for a soft and weak middle-zone.
The film extruded by this method consists, in all essence, of unoriented material. However, the system of alternating stiff layers of a "first polymer" and soft layers of a "second polymer" divided into filaments or the like in a linear pattern by the teeth, produces in each half-part of the sheet a tendency to split or flow in one direction, and since the linear patterns at the two surfaces criss-cross each other and a tendency to delaminate is provided, there is obtained a tear-stopping effect which is analogous to the "forking" effect in a true cross-laminate.
The above specification further proposes to biaxially stretch the so produced laminate under such conditions that instead of yielding biaxially oriented layers, the molecular orientation will become generally uniaxial in each layer, with the direction of orientation in different layers criss-crossing each other. In order to obtain such uniaxial direction, the second material must be very prone to yield, e.g. because it is still molten or semimolten while the first material is solid, and the filaments of the first material must be kept straightened out by biaxial strain.
Although the above method would on principle solve the problems of obtaining a lower thickness and higher width in cross laminates, some essential difficulties were found during the later technical developments. It was confirmed that the extrusion method was commercially feasible for manufacture of unoriented film with high tear propagation strength, but with a low impact strength due to the lack of orientation. However, essential drawbacks were found in connection with a subsequent biaxial stretching. As also indicated in the above specification, one must use a relatively great number of rows of the teeth in the extrusion die in order to obtain the fibre fineness which is necessary for the stretching system.
This, however, made the maintenance of the die difficult and caused frequent "hang-up" of polymer lumps between the teeth. Further, the interaction between the teeth in one half-part of the die and those in the other half-part made it necessary either to use excessive amounts of soft middle layer material, or to limit the combing to two relatively thin surface zones of the sheet. Further, it was very difficult to establish and maintain the biaxial stretching conditions necessary for obtaining a generally uniaxial molecular orientation as described.
The present invention is based on the discovery that even a strongly biaxially oriented film, with the same orientation in two directions perpendicularly to each other, can exhibit a pronounced direction of splitability, provided the film is extruded from a blend and is melt-attenuated in connection with the extrusion. Due to the attenuation there is formed a unidirectional fibrous morphology which can be observed in an ordinary microscope. There is also produced a uniaxial orientation by the melt attenuation, but this orientation is generally very weak. When the film (which can e.g. consist of about 50% polypropylene and 50% polyethylene) is drawn at an angle to the grain direction, e.g. perpendicularly thereto, then the fibre portions, as seen on a micro-scale, will deflect and branch out; but it is still possible to follow the zig-zagging path of the grain from branch-point to branch-point, and when following different paths in this manner it will be found that, on a macroscale there is still a unidirectional grain. This micro-structure is very different from the filament structure described in the above British patent specification No. 1261 397.
After a certain elongation, e.g. about 40' perpendicularly to the grain, examination of the film in polarized light (or more exactly by x-ray diffraction) shows that the orientation is equal in all directions. After further drawing in the same direction, there is still a pronounced splitability along the grain direction, until at a certain point, e.g. about 80' total elongation, the splittability is equal in all directions. On further drawing, the main direction of splitability will coincide with the main direction of orientation. The film can e.g. be elongated 100' in this direction, and thereafter drawn in the original grain direction till the point where it has equal orientation in all directions. At this point there is again a marked splitability in the original grain direction, and by microscopical examination it will be possible, although difficult, to follow the zig-zagging course of the grain and see that on a macro-scale, the grain direction still in essence coincides with the direction of splittability.
Following this discovery, the method according to the present invention is characterized by comprising the steps of attenuating while extruding each of at least two layers of at least one molten polymer blend to impart to the polymer a unidirectional grain with a pronounced direction of splittability when solidified, before or after solidification of said layers uniting the layers into a common sheet with the grain direction or adjacent layers therein extending in criss-crossing relationship, while forming a generally weak bond, between said layers solidifying if not already solid, and finally biaxially orienting the solid laminated sheet thus obtained in several steps which each are generally substantially uniaxial at a temperature sufficiently low for maintaining a significant splittability in each layer.
The product produced hereby is a high-strength laminate comprising generally weakly adhered biaxially oriented films, each formed of a blend which exhibits a distinct fibrous morphology with the fibres forming a distinct unidirectional grain when measured on a macro-scale but with the fibre-portions strongly deflected from this direction as seen on a micro-scale and with the unidirectional grain in at least two of the films criss-crossing each other.
It has been found that the structure so formed is particularly suitable for almost any high-strength application where energy absorption is essential, no matter whether this is energy absorption during tear propagation, puncturing, or impact. The splittability of the layers in connection with the weak bonding between the layers produces a "forking effect" similar to that in cross-laminates of uniaxially oriented film, but the energy absorption during fast tearing (Elmendorf tear test) is essentially higher. Further, most impact properties, in particular Elemdorf impact strength, are improved, and so will usually be the energy-absorption during fast puncturing (Beach-strength). These improvements are considered to be partly a result of the biaxial character of the orientation in each layer, and partly of the distinct fibrous morphology. The biaxial orientation has the further advantage that the laminate according to the invention has shrinkfilm properties, which cross-laminates of uniaxially oriented films do not have.
It has been mentioned above that the process for producing cross-lamination of uniaxially oriented films, under practical conditions gives a rather high limit for sheet thickness (about 90 gr per sq.m for a 3-ply) and a rather low limit for sheet width. In both respects the present method is greatly advantageous due to the fact that the sheet is strongly stretched in two or more directions after the lamination. Thus, it is thechnically and economically feasible to obtain about 10 gr per sq.m weight for each of the films in the laminate, i.g. about 30 gr per sq.m for a 3-ply laminate. This greatly widens the field of uses.
While blends of very compatible polymers, e.g. different polyamides, will usually not form a grain as described, blends of semicompatible or incompatible coextrudable thermoplastic polymers will always do so, provided the contents of one polymer is not too predominant. To be on the safe side, there should not be more than 85% of any polymer in the blend. If the polymers are really incompatible, there should preferably be added an "alloying agent".
The best properties will be obtained if the grain is formed of crystal threads "cemented" together by small amounts of a surrounding elastomer. By small amounts is meant about 5-20% of the total.
In order to keep the contents of elastomer low and still obtain a distinct fibrous morphology with the elastomer tending to surround the other material the elastomer is preferably used as an "alloying agent" for two other polymers. Thus a preferable composition is two crystalline incompatible polyolefins--e.g. iso- or syndiotactic polypropylene and high- or low density polyethylene--with addition of a sticky polymer which bonds to both--e.g. atactic polypropylene, ethylene-propylene-rubber (preferably a sticky type with relatively high contents of propylene), and polyisobutylene of a molweight as commonly used for pressure sensitive adhesives.
The attenuation, by which the uniaxial grain is formed, can be carried out in different ways. It can e.g. be by gradual reduction of the spacing of the exit chamber in the extrusion die, or by passage of the molten material between a row of closely spaced partitions or the like in the die, or by stretching in molten state after the exit of the die, or by combinations of such steps.
The direction of splittability and the splittability in the layers is determined by measuring the tear propagation resistance by the tongue tear method in different directions. The direction of splittability is understood as the direction which exhibits the lowest tear propagation strength, while the splittability is understood as the ratio between the highest tear propagation resistance and the lowest tear propagation resistance. The splittability in the layers after the biaxial orientation should preferably be bigger than 2:1, however 1.5:1 can be tolerated.
In order to allow a local delamination during tearing, and thereby make the tear "fork", it is essential to form a generally weak bond in the lamination of the layers. If the bond formed is an even bond, and the thickness of each layer is 20 gr per sq.m, a peel strength between about 5 gr per cm and 500 gr per cm is generally suitable. Since there is a "competition" between rupturing forces and delaminating forces during tearing, the upper limit depends on the layer thickness and is generally proportional to the latter.
As it will appear from the description of various embodiments, there exist different means to establish and control the strength of the bonding, of which the most practical involve at some step a coextrusion of a special layer of adhesive component or "release component".
As regards the biaxial orientation, it has been found essential to carry it out in several steps which each are generally substantially uniaxial. It was hereby found that simultaneous stretching in two directions destroyed the grain so that no "forking effect" was achieved. There is also a tendency to destroy the grain by stretching near the melting point of the major components of the sheet. I believe that recrystallization and other physical phase-rearrangement phenomona play a role in this connection. In any case the best properties have been found by stretching below the recrystallization temperature which e.g. for polypropylene is about 70.degree.-80.degree. C., and even lower temperatures are preferable. For stretching at such low temperatures special stretching methods are necessary which will be dealt with later in this specification.
Preferably the biaxial orientation produced by the stretching below the melting point should in any direction have a component at least equal to the orientation produced by the melt-attenuation, and generally it is preferable to make the biaxial orientation much stronger. Degree of orientation should in this connection be measured by x-ray defraction, but for quick and approximate examination of relative values, observations of interference colors between crossed polaroid filters are also suitable.
As explained above it is essential that the bonding between the grainy layers is generally weak, in order to enable a local delamination to take place during tear propagation. This, however, does not necessarily mean that the bonding must be weak all over the surface, but on the contrary great advantage for tear strength is generally achieved when employing the embodiment described in claim 2. Hereby, the necessary local delamination is easily started, but is thereafter stopped or will proceed under great resistance. At the same time the strongly bonded portions prevent a delamination of the laminate in or adjacent to a glued or welded seam under tension, which otherwise can easily occur.
By a suitable choice of the bonding pattern, the different bonding strengths, and the type of rupture in the weak-bond or no-bond areas--whether brittle or more fluid-the tearing properties can be "tailor-made" for different purposes.
The method in claim 2 is particularly useful in connection with relatively thin layers. It has already been mentioned that there is a "competition" between rupturing and delaminating forces during tear propagation, which means that easier start of delamination is required the thinner the layers are. As a practical rule, it will almost always be advisable to apply the method of claim 2 if the layers are thinner than about 40-50 gr per sq.m.
The use of strong-bond/weak-bond or strong-bond/no-bond patterns are in fact well known in connection with cross-laminates of films which are uniaxially oriented or are biaxially oriented in a very unbalanced manner, cf. the specifications of U.S. Pat. Nos. 3,496,056 and 3,342,657 and Brit. Pat. No. 1316640 and Danish Pat. No. 119733. However, the layers of such known laminates, when tested individually, exhibit extremely low impact and puncture resistance (except in case of special and expensive polymers such as e.g. nylon 6), whereas it has been found that the individual layers according to the present invention exhibit pronouncedly and surprisingly higher impact and puncture resistance. Therefore, a weaker adhesion (or no adhesion) in the relevant areas and/or a larger extension of these areas is allowable without any significant loss of impact or puncture strength.
A preferred way of forming or improving the effect of the generally weak bond between adjacent layers is described in claim 3.
By release substance is here meant a substance, preferably a polymer material, with either a low cohesive strength in itself or with a low adhesion to the adjacent polymer layer.
Whether a release or an adhesive substance is to be chosen depends on whether and to what extent the polymer blends are compatible with each other and of the uniting method, e.g. the temperature used during lamination.
In any case, by means of the method according to claim 3, it is possible to better control the magnitude of the bonding force.
A preferred way of effectuating the bond is described in claim 4 whereby one obtains the advantage that during tearing, the free or weakly bonded parts of the midlayer will elongate because of the stretching forces applied, and will absorbe some energy thus further stopping the notch effect.
Although there are several operational advantages by uniting the layers inside an extrusion die, as will be described later with reference to claim 22, the embodiment according to claim 5 is preferable with respect to the properties obtained, since it enables the formation of the most pronounced uniaxial grain in each layer.
An embodiment of the method according to claim 5 is described in claim 6, where the solid, preproduced film may be placed around a mandrel that extends through the centre of the extrusion die. The solid film can be forwarded along the mandrel and when passing the exit slot of the extrusion die, catching and forwarding and thus attenuating the rotated, still fluid polymer which in that way is wound around the solid film forming an outer film with a helically running grain.
As already mentioned, the tear propagation strength for a given total thickness is significantly better in a 3-layered laminate than in a 2-layered laminate. Therefore it is also preferable to extrude two or morefilms successively out of two or more mutually contrarotating extension slots onto the same solid film in the manner mentioned above.
Further advantages of the methods according to claim 6 are the possibility of producing fully uniaxial grain during the individual oblique haul-off, the possibility of chockcooling the polymer on the mandrel, thereby achieving a finer grain and less tendency to age by recrystallization, as well as higher working speed and the possibility of allowing the use of more difficult polymers, e.g. polymers of particular high molecular weight because of the supporting and conveying effect of the film on the mandrel, which can be very close to the circular exit slot.
In the above description, the rotating fluid tubular layer is drawn inwardly from the rotating extension die to the solid conveying film. This feature will generally be advantageous because the elastic tensions produced by the rotation tend to reduce the diameter of the tubular fluid film, thus promoting the catching of the fluid film of, and its sticking to the forwarded, solid film.
However, it is also within the scope of claim 6 to arrange the solid, forwarded film in a generally tubular shape with a diameter greater than that of the rotating exit slot, and by blowing or by other means extrude the fluid, rotating, tubular film outwardly onto the solid film.
It should be mentioned, that the rotating part may be the forwarded, solid film while the extrusion die is fixed.
It should be noted, that by "machine direction" is here meant the forwarding direction of the solid preproduced film.
A preferred embodiment of the method according to the invention is described in claim 7. The advantage of this embodiment is in the first place, that the different process steps, viz. extrusion, attenuating, uniting with the grain of adjacent layers in criss-crossing relationship and biaxial stretching, can be carried out in line. Preferably the sheet consists of three layers with the grain of the midlayer extending longitudinally as will be further described later in connection with the description of the drawings.
Compared to the embodiment in claim 6, the embodiment in claim 7 has the operational advantage that all layers are extruded from the same die, but this is achieved at the expense of the conveying effect.
By solidifying each grainy layer before they are united to a common sheet as described in claim 8 simpler or more conventional equipment can be used. A preferred embodiment of this method according to claim 8 is to produce the sheet as described in claim 9 with particularly cheap and simple machinery (at the expense of the advantages connected with an in line operation).
Another preferred embodiment of the method according to claim 8 is to produce the sheet as described in claim 10. This will give the possibility of producing rather wide layers. The lateral tentering can be carried out by means of a tenter frame preferably in an oven with circulating air which is kept at a temperature slightly above the melting point.
In order to simplify the lamination of separately extruded and solidified films, and thereby also make lamination of thinner film possible, at least the first phase of the uniting process may be combined with at least the first phase of the lateral stretching process as said in claim 11. This essentially helps prevent the formation of pleats during lamination. If the desirable stretching temperature is lower than the temperature necessary for sticking the films together, the first e.g. 10-20% of the stretching can take place at a higher temperature without any noticable harm.
In order to facilitate the uniting in connection with the method of claim 5, a lower melting adhesive polymer may be coextruded on at least one surface of at least one layer as said in claim 12.
This can be carried out as described in claim 13, with the practical advantage of avoiding controlled heating means, whereby the apparatus becomes particularly cheaper. In this connection, it has been found that the simultameous stretching of two films while they are pressed together--particularly as in the embodiment of claim 19, to be described below--has a surprisingly high tendency to cold-weld the films together, so that only a small degree of stickiness is required. E.g. surface layers of polyethylene with 16% vinylacetate copolymerized have been found to weld at room temperature in this manner, yielding a peel-strength of 10 gr per cm. The bonding strength can subsequently be increased by passage over or between heated rollers.
The adhesive polymer may be coextruded in stripes as said in claim 14. It is hereby possible to expediently obtain the strong-bond/weak-bond or strong-bond/no-bond pattern explained in connection with claim 2.
Another method of expediently obtaining a bonding pattern of the said kind consists in coextruding on one of adjacent surfaces of two layers a continuous ply of an adhesive polymer, and further to provide stripewise or spotwise the other of said surfaces with a release layer, as mentioned in claim 15.
Still another method to obtain the said kind of bonding pattern is to coextrude the adhesive polymer as described in claim 16. By this feature the zones of no-bond form a dotted configuration.
A very important embodiment of the method according to the invention is described in claim 17. As previously mentioned, the stretching process is preferably carried out at a relatively low temperature, e.g. room temperature, and use in the normal way a tenter frame under those circumstances will almost inevitably give an uneven "necking-down" with a laterally varied tear-propagation strength.
It is known to produce lateral stretching under even application of the stretching forces, see French Pat. No. 1.331.095 and Brit. Pat. No. 1.073.732. Both make use of 2 rubber conveyor belts which are expanded laterally at the same time as they are firmly pressed together, thereby gripping and drawing the film. However, for use in the present invention the simpler method of claim 18 has proven more convenient. In this connection it should be noted that a strictly even distribution of the stretching forces are not necessary but--on the contrary--a certain uneveness on a fine scale will be advantageous as far as tear propagation strength is concerned. It has in particular been found advantageous for the tear propagation strength to let the state of orientation vary according to a pattern of striations--see FIGS. 2 and 3--in such manner that in one set of striations the biaxial orientation is unbalanced and is strongest parallelly or nearly parallelly to the striations, while in the intervening striations it is also unbalanced but is strongest perpendicularly or nearly perpendicularly to the striations. In order to obtain this pattern, the stretching method of claim 18 can with advantage be carried out as specified in claim 19.
When especially high tear propagation and puncture resistance are desirable, and relatively low yield point is allowable, the stretching is carried out as further specified in claim 19. There is hereby obtained a higher elongation at break. In order to allow the contraction at the same time as the longitudinal stretching is carried out in a narrow zone, the laminate is preferably supplied with very fine, longitudinal pleats--in anology to what is disclosed in U.S. Pat. No. 3,233,029. In this connection, a suitable result is usually obtained when the fine pleats formed by the last step of the lateral stretching method of claim 19 are maintained in the sheet when the latter is fed into the longitudinal stretching zone.
Although it is stated above that there are advantages in producing a striated pattern of orientation and thickness variations, especially with a view to the tear propagation resistance, this effect should normally not be exaggerated since this would have an adverse effect on printability as well as on the puncture resistance against sharp items.
The object of claim 19 therefore is to avoid an exaggerated tendency to sharp formation of the linear stretching zones, which usually would occur if the sheet were longitudinally oriented in any significant degree.
With regard to the attenuation and the uniting of the layers, another preferred embodiment of the invention is described in claim 22. Hereby one loses some of the advantages achieved by the method according to claim 5--since it is hereby impossible to obtain truly uniaxial directions of grain--but grains the advantages of an operational sort to handle only one common sheet outside the extrusion die.
It is simple to construct the extrusion die-parts for extruding three or more layers, which as previously mentioned has several advantages.
It is preferable in addition to the features according to claim 22 to coextrude a polymer for controlling the adhesive strength as said in claim 23.
Due to the fibrous morphology, the stretching process will normally produce internal but usually not trespassing voids in the grainy layers. This effect is particularly significant when the stretching takes place at a relatively low temperature, and more or less opaqueness is produced hereby. This effect can be utilized to substitute white pigmentation, but can also be abolished by subsequent pressure rolling as specified in claim 24.
The invention will now be described in more detail with reference to the drawings, of which
FIG. 1 shows a section through an extrusion-die for manufacturing of a sheet material according to the invention.
FIG. 2 in perspective view with displaced sections shows the principle of an extrusion die with two counter-rotating exit slots and means to extrude two layers through each slot.
FIG. 3 in similar view shows the principle of an extrusion die with two counter-rotating and one fixed slot and with interjacent exit slots for air streams.
FIG. 4 in perspective view and partly in section shows the principle of a rotating, ring formed extrusion die with a mandrel extending through its centre.
FIG. 5 is a flow-sheet of the process regarding a preferred embodiment of the method according to the invention.
FIG. 6 is a process-line of a preferred cold stretching method.
FIG. 7 is a detail of the "grooved rollers" which perform the lateral stretching in uneven zones, called "striations".
FIG. 8 is a schematical sketch, on an enlarged scale, of the pattern of the striations and the orientation therein, of a film cross-stretched according to the process-line of FIG. 6.
FIG. 9 is an enlarged cross-section of the film of FIG. 8 as actually found by microscopy, however for the sake of clarity, the thickness is shown on a scale twice that of the width.
The extrusion die shown in FIG. 1 is an example of how to carry out the method, in which two polymer-in-polymer dispersions are extruded into a common collecting chamber through two rows of partitions, which are rotating in opposite directions. The two dispersion streams 1 and 2 are fed through inlet channels in the lower part of the die to annular channels 4 and 5 respectively in the two walls in the track 6, in which the two rings 7 and 8 are moved in opposite directions by driving means, e.g. by teeth and toothed wheels (not shown). The two rings 7 and 8 are supplied with rows of partitions 9 and 10 respectively, by which two rows of openings 11 and 12 are formed, through which the two dispersions are extruded into the collecting chamber 15, formed by the two parts 13 and 14, and terminating in the exit slot 16. For the sake of simplicity the partitions 9 and 10 are shown radially extending, but in real fact they are placed at an angle to the radial direction to prevent the formation of die-lines in the extruded sheet. By the extrusion through the two rotating rings 7 and 8 the two dispersions will each become attenuated and will hereby acquire a fibrillar morphology. The two arrays of attenuated streams will thereafter unite in the collecting chamber 15 and form a laminate with criss crossing fibrous morphology. The thickness of this laminate is reduced by the passage through the exit slot 16 and further by a normal draw-down and blow process. Hereafter the film is stretched both in the longitudinal and the transverse direction at a relatively low temperature. Due to the two different fiber directions the two half-parts of the film will exhibit tendencies to split in different directions during tearing. The materials, from which the two half-parts are formed, are so selected that they adhere poorly to each other. The material will thereby delaminate in a small area around the incission, from which tearing takes place, and this will smooth out the notch effect.
The die shown in FIG. 2 consists of four main parts, viz. a fixed inlet part (17) for circular distribution of the polymers as explained below, a fixed bearing part (18), and supported hereby the two rotating parts (19) and (20) which form one exit orifice (21). The polymers (A) and (B) are fed to the inlet part (17) where they are distributed in concentrical circular streams. (A) is extruded through the annular conduits (22) and (23), for which either one or two extruders may be used. (B) is extruded through the annular conduit (24). For even distribution, (22), (23) and (24) are supplied with distribution baffles or other distribution means (not shown).
For the sake of clarity, the bearings and sealings between the bearing part (18), the rotating part (19), and the rotating part (20), are not shown, neither are the drives for (19) and (20).
From the three annular conduits (22), (23) and (24) the polymer streams pass the bearing part (18) through three circular arrays of channels (25), (26) and (27), each communicating with an annular chamber (28), (29) and (30) respectively.
The two rotating parts (19) and (20) are preferably rotated at almost equal velocity, but in different directions, as indicated by the arrows (31) and (32). Each rotary part in itself is a coextrusion die for two layers, one consisting of (A) and one of (B). For the sake of clarity, reference figures for explanation of the flow are shown only on part (20), but the flow through part (19) is similar. From the chamber (29) polymer (A) passes into the rotating part through channels (33), while polymer (B) from chamber (30) passes into the rotating part through channels (34). Inside the rotating part are two annular conduits (35) and (36) in communication with, respectively the channels (33) and (34), and separated from each other by a thin circular wall (37).
Having passed the edge of the wall (37), (A) and (B) merge together in an annular collecting chamber (38), which terminates in the exit orifice (21). By the passage through the collecting chamber (38) and into the exit orifice (21), the thickness of the fluid sheet is strongly reduced whereby the material is attenuated.
The partitions between adjacent channels (33) and (34) respectively ought to be streamlined, as shown. For the sake of clarity they extend radially in the drawing, but in real fact they should be forming an angle with this direction to reduce the tendency of the forming of die-lines.
"Polymer A" is a blend of two incompatible or semi-compatible polymers, while "Polymer B" is adapted to give the sheet a suitable tendency to delaminate. It may therefore, e.g. consist of an elastomer which is a poor adhesive for the two layers of A, and may be extruded in stripes. However, if the channels 22 and 23 are fed with two different polymer blends, that are mutual incompatible, the polymer B may be an adhesive with a relative strong bond to the two polymer blends, and it must in that case be extruded in stripes or otherwise interrupted.
The device shown in FIG. 3 consists of essentially similar main parts (39), (40), (41) and (42), but there is one exit slot (53) and (54) respectively in each of the rotating parts (41) and (42), and there is further a fixed exit slot (43) which is formed by the bearing part (40). From the three sets of annular conduits (44), (45) and (46) the polymer streams (C) and (D) pass the bearing part (40) through channels (47) and (48), respectively, and into the three annular chambers (49) and (50), of which the latter continues in the fixed exit slot (43). Each of the chambers (49) is formed of a fixed part (40) and a rotating part (41) or (42). Through channels (51) in (41) and (42) each of the chambers (49) communicate with the corresponding one of the two annular chambers (52) in the rotating parts, and each chamber (52) terminates in an exit slot (53) and (54), respectively.
Arrows (55) and (56) show the direction of rotations.
Having left the die, the three tubular films are fused together at the same time as the two films formed of (C) are subjected to torsion due to the rotations of (41) and (42).
From the outside and inside of the part (40), air is led through channels (55) ending in orifices (56). For the sake of clarity, the channels (55) from the outside of the part (40) are not shown. Through other channels (57) in the parts (41) and (42), the air is led through exit slots (58) and (59) between the fixed part (40) and the rotating parts (41) and (42) respectively. The channels (57) in the part (42) are not shown, for the sake of clarity. The ringformed pockets of air thus created between adjacent layers, prevent the rotating outer and inner polymer films to pleat against the midlayer immediately outside the exit slots.
Preferably the extruded film is blown, and both internal and external air-cooling is applied.
The arrangement shown in FIG. 2 is usually simpler to operate than that shown in FIG. 3, while the latter offers some special possibilities. One is to use expanded polymer for the middle layer, and another is to achieve a longitudinal grain in this layer, so that there will be 3 grains in the sheet. The presence of 3 instead of 2 directions in connection with the preferable tendency to delaminate, will significantly increase the tear propagation strength. Besides the attenuation process is more definitely finished before the lamination, which as previously mentioned is advantageous.
In FIG. 4, (60) is a rotating ringformed extrusion die. Through a fixed part of the extruder-die (not shown), which is in sealed connection with the rotating part (60), a polymer blend is fed into a circular groove (61) and led to the exit slot (62) through channels (63), that are separated by thin, plateformed partitions (64). For the sake of clarity the partitions (64) are shown radially extending, but they are in real fact forming an angle with radial plans to avoid die-lines in the resultant sheet. (65) is a mandrel that is fixed by means, not shown, and (66) is a longitudinally attenuated preproduced flat sheet, folded to a tubular shape around the mandrel (65). For the sake of clarity a space is shown between the mandrel (65) and the folded sheet (66), but naturally the sheet is lying tight towards the mandrel. The sheet (66) is pulled through the extrusion die over the mandrel as indicated by the arrow (67). When the polymer film (70) still fluid leaves the rotating exit slot (62) it is caught by the folded sheet (66) because of the elastic retention in the attenuated polymer blend, and thus wound around said folded sheet and forewarded along with it, obtaining a helically running direction of splittability indicated by the arrows (68).
The direction of splitability in the preformed, folded sheet (66) is indicated by the arrows (69).
The bonding strength may be controlled e.g. by coextruding an adhesive layer with the film (66). With a sufficiently high temperature of the mandrel (65), the lamination of the sheet may be effectuated on this. However, often the film (70) is preferably chock-cooled on the mandrel, in which case the temperature of the mandrel may be insufficient for the welding of the two films (66) and (70) together. The lamination may therefore be completed by hot- or coldwelding after the films have left the mandrel (65).
With the words "machine direction", which is used earlier in the description with regard to claim 5 is ment the forewarding direction of the sheet (66).
The flow-sheet of FIG. 5 schematically mentions the different steps of a preferred method in which the use of rotating die-parts are avoided. The last two steps can be carried out by the cold-stretching method indicated by the process-line of FIG. 6, in which section "Q" is the cross-stretching line and section "R" is the longitudinal stretching line. The system of rollers in section "Q" consists of driven nip-rollers (71), driven grooved rollers (72), idle rollers (73) and banana rollers (74). The banana rollers (74) after each step serve to draw out the pleates produced by the lateral stretching. Over the idle roller (75), the film (79) enters section "R", the longitudinal stretching line, where it is drawn through a water bath (76) serving to abolish the stretching heat and maintain a suitable stretching temperature e.g. at 20.degree.-40.degree. C. onto a bobbin (77).
The arrow (78) indicates the machine direction.
In FIG. 7 a pair of driven grooved rollers (72) are shown in detail with the film (79) pressed and stretched between the teeth (80) of the rollers (72).
In FIG. 8 the relative lengths of the arrows in the striations I and II of the film (79) indicate the relative amounts of orientation achieved by the biaxially stretching method shown in FIG. 6 and FIG. 7.
In FIG. 8 as well as in FIG. 9 the numbers I and II indicate the striations, which generally have varying width and uneven character. Furthermore it should be noted, that the outer layers (81) and (82) of the film (79) are not always symmetrical with respect to the thin midlayer (83). This assymmetry further serves to make a tear "fork".
For economical reasons, the present invention is particularly useful in connection with blends which mainly contain crystalline polyolefins. Best are for the most common application blends of polypropylene and high- or low-density-polyethylene. What blending ratio should be applied, and whether high- and low-density polyethylene should be used depends on the desired stiffness, low temperature strength, and in general on which strength properties are particularly wanted. In order to obtain a sufficient cohesive strength in each layer, the polypropylene should either be a copolymer semi-compatible with polyethylene, e.g. polypropylene with 2-5% contents of ethylene, or there should be used a suitable "alloying agent". In this connection it is sufficient to maintain high contents of the atactic modification in the iso-(syndio-) tactic polypropylene during manufacture of this polymer instead of removing this "impurity", as normally done. It is a special object of the invention that polypropylene with high contents of the atactic material can be made highly useful. Other "alloying agents" have been mentioned earlier in the specification.
Economically interesting are also blends of polypropylene and an elastomer--e.g. ethylene-propylene-rubber, ethylene-vinylacetate copolymer, polyisobutylene or a "thermoplastic rubber" based on butadiene/styrene.
When particularly high low-temperature resistance and/or high flexibility is desired, blends of low-density polyethylene and a semi-compatible rubber is preferable. It will be understood that the blend needs not be formed by mechanical blending, but can be formed already in the polymerization process. Thus, polypropylene with extreme high contents of the atactic component can be useful without any further admixture, and the brown polymerization processes which aim at making blends of polypropylene, polyethylene, and block polymers herebetween, can also be adapted.
Considering polymers outside the polyolefin groups, the following combinations for example will be useful for special purposes: (a) Polyester/polyamid or polyuretan, (b) polyester or polyamid/polycarbonate, (c) Vinylidene-copolymers in different combinations.
In addition to the layers with the special morphology as described, there may also be layers with special properties. Thus, it is almost always advantageous to co-extrude thin surface layers of a suitable adhesive component in order to enable sealing of the laminate without ruining of the orientation. As another example it will also often be necessary or advantageous, especially for food packaging, to add one or more special layers to improve barrier properties.
The high-strength laminate according to the invention is believed to be advantageous for use within the following fields:
(1) Food packaging: Heavy duty food bags in general, 100% plastics or combined with paper. Frozen food packaging.
(2) Non-food packaging: Fertilizer bags, cement bags, bags for valuable chemicals, e.g. plastic granules, bags for coarse chemicals (e.g. rock salt, rock pieces) and for other sharp items, wrapping of steel plates, packaging of carpets, baling-wrap, e.g. of cotton, wool, lumber wrap, grocery bags, individual packaging of machine-parts, weapons, etc., sterilization-bags for heavy or sharp objects, miscellaneous; e.g. for textile, apparel, paper, drugs, soaps, toilteries, tobacco.
(3) Film in connection with containers: Shrink wrap and stretch wrap for pallets, trash bags, in particular compactor bags, industrial shipping packs.
(4) Non-packaging: Fumigating film, earth cover for erosion control, lining in ponds, water reservoirs and channel construction, seed underlay, wind screens, green house film, plant-protection film (agricultural and horticultural), cover over dumps of agricultural and horticultural products, salt, etc., weathering protection of animals (animal "coats"), raincoats, tents, inflatable architectural structures, water inflated structures, lighter-than-air-buoyant structures, rib-constructions (architectural, cheap vessels), cusion-pillows as fillers in cargos, railroad car liners, truck covers, weathering protection over buildings under construction, water barrier over cement constructions to retard drying, insulation of roof under shingles, insulation of refrigeration rooms, "membrane-films" in house construction, ceiling tile, misc. building papers (in lamination with paper) cheap swimming-pool constructions, industrial tapes.
It will be understood, that the above described new extrusion methods and apparatus which make use of rotating die parts, will also have certain useful applications outside the field defined by claim 1. Thus, they can be used to extrude and laminate film without a "grain" as described, which still are applicable with advantage for certain purposes. Further, the general extrusion system shown in FIG. 4 and claimed in claim 6 can e.g. be used to spin a melt-oriented film (with or without a grain as described) around a cold-stretched film.EXAMPLE 1
A three layers tubular film is extruded in the following composition: Middle layer (70% of total)
85% isotactic polypropylene of gas-phase type ("Novolen") with high atactic contents
15% ethylene-vinylacetate copolymer (16% vinylacetate)
Both surface layers (one 10% of total, the other one 20% of total):
Ethylene-vinylacetate copolymer (16% vinylacetate)--to serve as adhesive layers.
The polypropylene has melt index 0.3-0.6 according to ASTM D 12 38 condition L, while the ethylene-vinylacetate copolymer has melt index 2.5 according to the same ASTM but condition E. The tubular film is extruded from a 1 mm wide slot at 180.degree. C.-230.degree. C. and drawn to 0.130 mm in molten state. The blow ratio is kept very low, viz. 1.2:1. Thereafter it is cut helically to a flat film with 45.degree. angle of "grain". Two much helically cut films, with their "grain" perpendicular to each other, and the thinner surface layers facing each other, are fed together at 20.degree. C. through 7 sets of "grooved rollers"--see FIGS. 6 and 7. The width of each groove is 1 mm and the width of each ridge is 0.5 mm. The intermeshing of the ridges with each other (difference of level between the tops) is 2 mm. Between each passage through a set of "grooved rollers" the pleats formed in the laminate are straightned out.
By the mechanical work between the "grooved rollers", and due to the copolymer layers which act as adhesive, the two films are hereby coldwelded together with relatively low bonding strength,--peel strength measured to 10 gr per cm--and is at the same time cross-drawn. After the 7 passages at 20.degree. C. the film is passed once through a similar set of "grooved rollers" with the same dimensions and intermeshing, but heated to 120.degree. C., whereby there is formed lines of strong bonding.
Finally the laminate is longitudinally oriented in three steps with about 1 cm stretching-gap (so as to minimize the cross-contraction). The last stretching is so adjusted that the total lateral cold-stretch-ratio and the total longitudinal cold-stretch-ratio are equal, whereby the product hereof i.e. the area-stretch-ratio is 2.4:1.
Test results compared to a heavy-duty bag quality low-density polyethylene film of 85% higher sq.m weight and melt index 0.3 according to same ASTM condition E. Gauge 100 gr per sq.m for the laminate and 185 gr per sq.m for the polyethylene film. Impact strength measured by falling-ball (diameter: 61 mm, weight 320 gr) for the laminated film of 100 gr per sq.m: 5.5 m.
For the polyethylene film of 180 gr per sq.m: 2.0 m
Tongue tear resistance:
Tearing at velocity 100 mm per min, total specimen width 5 cm, incission length 10 cm:
For the laminated film of 100 gr per sq.m: 5.9 kg in the machine direction and 6.8 kg in the transverse direction.
For the polyethylene film of 180 kg. per sq.m: 1.3 gr.
Elmendorf tear resistance (shock-tearing):
The test is a modification of standards aiming at a more symmetrical tearing. Results:
For the laminated film of 100 gr per sq.m: in longitudinal direction 441 kg cm per sq.cm, in cross-direction 344 kg cm per sq.cm.
For the polypropylene film of 180 gr per sq.m: in longitudinal direction 167 kg cm, per sq.cm in cross-direction 172 kg cm per sq.cm.
A piece of the sheet is delaminated by peeling and the structure is examined in microscope. The main layers have a pronounced fibrous morphology with zig-zagging grain-directions.EXAMPLE 2
The procedure of example 1 is repeated with the following modifications: The three-layers coextruded film had the following compositions: Middle layer (70% of total):
85% isotactic polypropylene (same type as in ex. 1)
15% ethylene-propylene-rubber (ab. same melt index as the polypropylene)
Both surface layers (each 15% of total) ethylene-vinylacetat copolymer (same type as in ex. 1) The film was stronger melt-attenuated after the exit from the die, namely by drawing from 1 mm thickness to o,o 65 mm (60 gr per sq.m). Examinations in polarized light showed that the melt-orientation produced hereby corresponded to about 35% uniaxial cold-drawing.
After the spiral-cutting, there was produced a 3-ply laminate. The third layer, which was placed in the middle, was with longitudinal "grain direction" obtained by longitudinal cutting of the same film. The lamination and drawing took place on the machinery of Example 1, but all steps were carried out at 20.degree. C., and the apparatus were adjusted to hereby produce a total area-stretch ratio of 2.5:1 by which the final laminate thickness became 72 gr per sq.m. The peel strength of the bonding between the layers was measured to 10 gr per cm. Examinations in microscope showed a similar structure as in Example 1. The following test results were obtained:
______________________________________ Comparison Present film unoriented 3 layers LDPE - film 72 gr/sq.m 184 gr/sq.m ______________________________________ Impact Strength gr 1000 gr .times. m 530 gr .times. m Tear propagation strength MD.sup.+ 848 gr .times. m 307 gr .times. m (slow tear) TD.sup.++ 1120 gr .times. m 620 gr .times. m Load at break MD 11.1 kg 10.6 kg (1" wide samples) TD 8.3 kg 10.7 kg Stretch at break MD 286% 467% TD 347% 620% Shrinkage 1 min. 130.degree. C. MD 28% -- TD 14% -- 1 min. 155.degree. C. MD 58% -- TD 41% -- ______________________________________ .sup.+ Machine Direction .sup.++ Transverse DirectionEXAMPLE 3
A series of sheets on polyolefin basis has been produced by the extrusion die shown in FIG. 2. The diameter of the exit slot (21) of the die was 130 mm and the width of the latter 1 mm. The biggest width of the collecting chamber (38) was 4 mm, which means that the amount of attenuation during the passage through the collecting chamber toward the exit slot has been smaller than preferable. The extrusion temperature was about 240.degree. C.
After the longitudinal cutting of the tubular film, the stretching was first carried out laterally in between 4 and 8 steps and thereafter longitudinally in between 2 and 4 steps in the same machinery as used in examples 1 and 2.
The composition, flat tube width (measure of blow ratio), stretching temperature, stretch ratio, and results appear from the table below. "Nov" stands for Novolene, a gas-phase polymerized polypropylene with relatively high contents of the atactic modification, "PE" stands for low density polyethylene, "EPR" stands for ethylene-propylene-rubber, "SA 872" "'7823" and "8623" are different types of polypropylene with minor contents of polymerized ethylene.
The fact that even the best samples of this example generally are inferior to those of example 1 and 2 are explained by a less uniaxial total melt attenuation. A certain biaxial melt-attenuation is inevitable in this embodiment, since the streams are first united inside the die in cross-crossing relationship, and thereafter further melt-attenuated during the passage through the exit and immediately thereafter. On the other hand, this method is particularly simple to operate.
__________________________________________________________________________ cm Outer Layer Middle Layer Orientation T. Tongue Tear Dart Impact Composition Composition Temp. % W. MD TD (ft - lbs) __________________________________________________________________________ 1 70% 7823, 20% PE, 10% EPR PE - 10% Cold 100% 30 3.3 1.8 2.5 2 80% 7823, 20% EPR PE - 10% Cold 100% 30 1.7 1.6 2.5 3 80% 7823, 20% EPR PE - 20% Cold 100% 30 2.7 2.3 2.5 4 70% SA872, 30% PE PE - 10% Cold 50% 30 7.1 4.6 2.0 5 70% SA872, 30% PE PE - 10% Cold 100% 30 5.7 2.1 2.5 6 70% SA872, 30% PE PE - 10% Hot 50% 30 9.0 4.5 2.0 7 70% SA872, 30% PE PE - 10% Hot 100% 30 7.5 3.0 1.5 8 70% SA872, 30% PE PE - 10% Cold 50% 45 6.6 1.4 2.0 9 70% SA872, 30% PE PE - 10% Cold 100% 45 2.6 1.4 2.0 10 70% SA872, 30% PE PE - 10% Hot 50% 45 5.8 2.4 2.0 11 70% SA872, 30% PE PE - 10% Hot 100% 45 6.4 2.3 2.2 12 100% SA872 PE - 10% Cold 100% 30 1.2 3.3 2.5 13 100% SA872 PE - 10% Cold 100% 30 2.0 1.1 1.5 14 100% SA872 50/50 EPR/PE - 10% Cold 100% 30 2.1 1.5 2.5 15 100% SA872 50/50 EPR/PE - 10% Hot 50% 30 3.1 2.1 1.5 16 100% SA872 50/50 EPR/PE - 10% Hot 100% 30 1.4 1.4 1.5 17 100% SA872 EPR 10% Cold 100% 30 5.6 2.8 2.0 18 80% 7823, 20% EPR EPR 10% Cold 100% 30 4.4 1.9 4.0 19 70% 7823, 20% PE, 10% EPR EPR 10% Cold 100% 30 4.5 2.9 3.0 20 70% SA872, 30% PE EPR 10% Cold 50% 30 6.4 3.0 1.5 21 70% SA872, 30% PE EPR 10% Cold 100% 30 3.9 2.1 3.0 22 70% SA872, 30% PE EPR 10% Hot 50% 30 4.9 3.9 1.5 23 70% SA872, 30% PE EPR 10% Hot 100% 30 5.2 3.4 2.0 24 70% SA872, 30% PE EPR 10% Cold 50% 45 6.0 5.0 1.5 25 70% SA872, 30% PE EPR 10% Cold 100% 45 5.0 3.2 3.0 26 70% SA872, 30% PE EPR 10% Hot 50% 45 5.6 3.9 1.5 27 70% SA872, 30% PE EPR 10% Hot 100% 45 5.0 5.4 3.0 28 86% 8623, 10% PE, 5% EPR EPR 10% Cold 100% 30 0.63 0.32 2.0 29 90% 8623, 10% EPR EPR 10% Cold 100% 30 0.45 0.26 2.0 30 100% SA872 50/50 - EPR/PE - 20% Cold 100% 30 4.4 4.3 3.0 31 100% SA872 50/50 - EPR/PE - 5% Cold 100% 30 4.5 3.5 2.0 32 80% SA872, 10% PE, 10% EPR 50/50 - EPR/PE - 10% Cold 100% 30 3.4 6.3 3.0 33 34 70% Nov, 30% PS 50/50 EPR/PE - 10% Cold 100% 30 4.8 2.4 2.5 35 70% PS, 30% Nov EPR 10% Cold 100% 30 4.9 4.2 4.0 __________________________________________________________________________ Beach Puncture Trapezoidal Tear Elmendorf Tear Mullen Burst (psi) MD TD MD TD TD Basis Weight __________________________________________________________________________ (g/m.sup.2) 1 20 129 136 6.5 7.1 500-1400 500-1300 73.5 2 30 242 228 8.9 6.8 800- 500-2500 69 3 26 295 241 7.8 6.4 300-1100 300-1000 62 4 37 86 105 11.6 9.5 1200-2400 400-2000 114 5 27 103 118 11.9 7.7 400-2000 1400-3200 73.3 6 35 66 98 10.2 11.4 100-1700 1500-2300 103.7 7 30 67 98 13.6 12.7 500-1500 2400-3000 86.5 8 20 71 105 8.7 8.8 100-800 1100-2600 77 9 19 69 120 7.8 5.0 200-2900 2200-3200 63.4 10 25 44 52 7.7 8.2 300-1100 1100-3200 77.8 11 20 36 88 9.9 8.7 500-1700 700-3200 61.1 12 21 113 103 6.3 5.4 200-1800 600-2200 54.6 13 22 70 68 7.9 5.8 310 800-2100 79 14 22 126 140 5.3 7.4 200-3000 1500-3200 70.4 15 26 56 44 9.5 8.1 300-3200 100-300 83.2 16 29 72 64 10.7 7.8 150-2500 200-3200 71.5 17 29 83 105 9.8 8.9 700-3200 800-2000 84.5 18 23 327 278 12.5 8.4 700-3000 1400 88.4 19 20 212 187 10.4 9.0 1000-3200 900-1300 71.4 20 23 93 105 10.3 8.9 300-3200 1100-3200 74.8 21 21 100 115 8.2 7.6 300-3200 700-2100 70 22 26 55 71 11.5 7.4 600-2400 1200-2500 86.9 23 20 110 116 8.6 10.2 200-2200 700-1600 64.8 24 26 67 149 13.2 10.1 1400-3000 800-3000 88.7 25 23 124 145 11.5 7.9 1100-2500 1000-2300 82.9 26 23 120 101 9.6 9.3 320-3200 1200-3200 83 27 21 116 113 5.7 8.9 680-3200 600-2700 76 28 20 105 50 2.4 1.8 350 96 66.3 29 15 66 73 1.8 1.5 240 96 74 30 24 99 94 9.0 7.7 800-2000 2600-3200 73.8 31 23 74 107 8.6 8.4 1400-2000 700-2700 81.7 32 25 110 117 8.4 9.4 700-2000 2400 70.4 33 34 23 228 194 7.0 7.9 6.8 35 23 336 343 8.6 6.9 71.2 __________________________________________________________________________
1. A method of simultaneously laterally stretching and laminating together at least two separate films formed from at least one thermoplastic, orientable polymer which comprises the steps of positively advancing said separate films under tension in generally spread out condition with the adjacent surfaces of each adjacent pair of said films in direct face-to-face contact to form a sandwich of separate films; and while maintaining said films in said tensioned sandwich condition and at a temperature substantially below their melting point, applying mechanical pressure to the opposite sides of the advancing film sandwich alternately in directions perpendicular to the opposite sandwich faces along a multiplicity of generally uniformly closely spaced loci extending parallel to the direction of advance to positively deflect said sandwich into a temporary generally uniform laterally zig-zag or pleated configuration to said sandwich, the magnitude of said mechanical pressure and the deflection produced thereby being sufficient to mechanically work the mutually contacting surfaces of adjacent pairs of films in said sandwich along said loci and thereby impart a permanent lateral stretch while coincidentally effecting cold-weld bonding together of the mutually contacting film surfaces.
2. A method according to claim 1 in which the temporarily pleated configuration is imparted to the film sandwich by means of an opposed pair of moving rollers between which the film sandwich passes, the surface of each such roller having projecting crests alternating with grooves, said projecting crests and grooves being either circular or of spiral form, the crests of one roller interdigitating with the grooves of the other roller to a depth sufficient to produce said magnitude of devlection but without contacting the bottoms of the grooves of said other roller.
3. A method according to claim 1 in which said film sandwich is subjected to said positive deflection while at substantially room temperature.
4. The method of claim 1 wherein after said film sandwich has been subjected to at least one step of positive deflection at room temperature, it is subjected to an additional deflection step while being heated along said loci.
5. The method of claim 1 in which said magnitude of deflection exceeds the distance between said loci.
6. A method according to claim 2 in which the total width of each projecting crest and an adjacent groove is of the order of magnitude of one to a few millimeters.
7. The method of claim 1 wherein said film sandwich after being deflected into said temporarily pleated condition is spread laterally to substantially its full width and then is deflected a second time into said temporarily pleated condition.
8. A method according to claim 1 in which the films to be laminated and stretched are co-extruded films carrying on at least one surface a layer of polymer of lower melting range than the interior of the film.
9. A method according to claim 8, in which said lower melting polymer is coextruded in stripes.
10. The method of claim 1 wherein the steps of deflecting and spreading said film sandwich are repeated a sufficient number of times to laterally orient substantially the entire area of the film sandwich, and subsequently subjecting the laterally stretched and cold-welded film sandwich to longitudinal stretching orientation while permitting the film sandwich to laterally contract.
11. Apparatus for simultaneously laterally stretching and laminating together films of thermoplastic orientable polymer which comprises means for positively advancing under tension at least two separate films of said polymer in generally flat spread out condition with the adjacent surfaces of each adjacent pair of said films in direct face-to-face contact to form a sandwich of at least one pair of said separate films, and means for applying mechanical pressure to opposite sides of said advancing sandwich in alternating directions perpendicularly out of the faces thereof along generally uniformly closely spaced loci extending parallel to the direction of advancing to positively deflect the advancing sandwich and impart a temporary generally uniform zig-zag or pleated configuration thereto, the magnitude of such deflection being sufficient to mechanically work the mutually contacting surfaces of each adjacent pair of films along said loci and thereby impart a permanent lateral stretch while coincidentally effecting cold-weld bonding together of the mutually contacting film surfaces.
|November 1935
|April 1941
|November 1943
|Rowe et al.
|October 1947
|August 1953
|Goodwin et al.
|March 1962
|December 1962
|Wyckoff et al.
|February 1966
|June 1966
|June 1966
|January 1967
|Cooper et al.
|April 1968
|October 1968
|December 1968
|November 1969
|January 1970
|June 1970
|February 1971
|Schrenk et al.
|September 1971
|Yazawa et al.
|January 1972
|June 1972
|June 1972
|October 12, 1976
|Lepoutre et al.
|August 2, 1977
|September 26, 1978
|December 16, 1986
|October 1963
|August 1967
Type: Grant
Filed: Jul 9, 1984
Date of Patent: Dec 27, 1988
Inventor: Ole-Bendt Rasmussen (3460 Binkeroed)
Primary Examiner: Jeffery Thurlow
Attorney: William J. Daniel
Application Number: 6/627,501
International Classification: B29C 6572;


text:
Wednesday, March 30, 2011
After installing a SharePoint Update and running the Configuration Wizard you may notice that the User Profile Synchronization Service Application has stopped. Attempts to restart the User Profile Synchronization Service Application may prove unsuccessful.
After installing a SharePoint Update and running the Configuration Wizard you may notice that the User Profile Synchronization Service Application has stopped. Attempts to restart the User Profile Synchronization Service Application may prove unsuccessful.
1) The User Profile Synchronization Service Application Fails is stopped and fails to restart
2) The following errors appear in the Event Viewer:
a. Detection of product '{90140000-104C-0000-1000-0000000FF1CE}', feature 'PeopleILM' failed during request for component '{1681AE41-ADA8-4B70-BC11-98A5A4EDD046}' b. Detection of product '{90140000-104C-0000-1000-0000000FF1CE}', feature 'PeopleILM', component '{1C12B6E6-898C-4D58-9774-AAAFBDFE273C}' failed. The resource 'C:\Program Files\Microsoft Office Servers\14.0\Service\Microsoft.ResourceManagement.Service.exe' does not exist.
a. Detection of product '{90140000-104C-0000-1000-0000000FF1CE}', feature 'PeopleILM' failed during request for component '{1681AE41-ADA8-4B70-BC11-98A5A4EDD046}'
b. Detection of product '{90140000-104C-0000-1000-0000000FF1CE}', feature 'PeopleILM', component '{1C12B6E6-898C-4D58-9774-AAAFBDFE273C}' failed.
The resource 'C:\Program Files\Microsoft Office Servers\14.0\Service\Microsoft.ResourceManagement.Service.exe' does not exist.
Give the Network Service account read/Execute permissions to the following folders:
\Program Files\Microsoft Office Servers\14.0\ \Service \SQL \Tools
\Program Files\Microsoft Office Servers\14.0\
Open Central Admin—>Application Management—>Manage Services on Farm—> Start the Profile Synchronization Service
Special Thanks to Greg Carter (HoganTaylor)
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Saturday, March 26, 2011
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Presentations & Training
Friday, March 25, 2011
posted @ Friday, March 25, 2011 10:36 AM | Feedback (0) |
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Presentations & Training
Friday, November 19, 2010
Thanks to all those who attended.
posted @ Friday, November 19, 2010 12:01 AM | Feedback (0) |
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Presentations & Training
Tuesday, October 26, 2010
While at the Tyson Developers Conference last week I attended a productivity session by Claudio Lassala. During the session he introduced us to a time management technique known as Pamadoro. Essentially, tasks are performed in 25 minute blocks with a five minute break between each work block. Today, I found a tool called Keep Focused on CodePlex.com. The tool allows a task to be entered then the 25 minute timer count down is started. I used Keep Focused all day and really felt quite productive.
Give Keep Focused a try and see if your productivity doesn't improve.
posted @ Tuesday, October 26, 2010 10:01 PM | Feedback (0) |
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Community & Events
Thursday, September 9, 2010
Creating a custom master page provides the greatest flexibility for branding a SharePoint Implementation. However, there are many hidden traps to be aware of when creating a custom master page. For example, it is usually best not to start from scratch but to use a copy of the v4.master or starter master page http://startermasterpages.codeplex.com/ created by Randy Drisgill.
The v4.master is the new default master used for SharePoint 2010 and creating a new custom master from a copy of the original v4.master will ensure the inclusion of expected SharePoint 2010 User Experience Functionality.
After deploying a custom master page based on the v4.master we began seeing a "You must specify a value for this required field" message box whenever trying to edit or add new list items and perform other routine tasks.
After much research the solution was found on this blog post: http://blogs.msdn.com/b/tmathis/archive/2010/03/18/you-must-specify-a-value-for-this-required-field-error-when-hidding-placeholderpagetitleintitlearea.aspx
It has always been a good practice to place unused content place holders within a hidden ASP.NET Panel Control. However, the message box error was caused by the PlaceHolderPageTitleInTitleArea content place holder being contained within an ASP.NET Panel Control with the hidden attribute set to false. The resolution was to remove the hidden=false attribute and hide the ASP.NET Panel using a CSS Style. The style can be simply added to the master page for easy deployment.
posted @ Thursday, September 9, 2010 8:34 PM | Feedback (0) |
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Over the weekend I spun up a new virtual machine for a practice TFS 2010 Installation. The TFS installation process is much improved. It can loosely be broken into two phases which are installation and configuration. The installation is the easy part which basically prepares the server and copies some bits to the drive. The configuration is a little more difficult but provides some guidance to help make the important decisions. During the configuration you make the following three key decisions.
During the configuration I received TF255275 Error during the Reporting Services portion of the configuration. My reporting services database was created and configured for SharePoint Mode.
Reference: http://www.sathishtk.com/blog/post/2009/10/15/TFS-2010-TF255275-Error.aspx
Despite referencing the TFS 2010 Beta the above blog post helped resolve the issue. Essentially, I had to change the database to Native Mode. However, as a commenter mentions I had to delete the Report Database and recreate it in Native Mode before the configuration wizard would complete.
posted @ Thursday, September 9, 2010 1:18 AM | Feedback (0) |
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Wednesday, August 18, 2010
After completing a MOSS 2007 SP2 to SharePoint 2010 (Enterprise) upgrade all seemed to go well. However, I soon began to notice some subtle differences between site collections. For example, the home site collection was missing the new Tag Cloud Web Part. So I seemed like perhaps a Feature wasn't Activated. After a little digging I learned that there is a Feature called Portal Layouts which is responsible for provisioning artifacts like the new Tag Cloud Web Part.
To Activate the Feature you can use either stsadm or PowerShell. The syntax for both is listed below:
stsadm -o activateFeature -name "PortalLayouts" -url "http://<SharepointServer>/sites/<SiteCollection>" –force
Enable-SPFeature FeatureFolderName -Url http://server/site/subsite
posted @ Wednesday, August 18, 2010 11:32 AM | Feedback (0) |
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Monday, June 7, 2010
A client was experiencing very strange behavior following an upgrade from MOSS 2007 to SharePoint 2010 Server. In a nutshell some documents such as Word (.doc and .docx) would open while others such as Excel (.xls and xlsx) and PDF documents would not open.
Note: By open I mean when clicking on an Excel document, stored within a document library, it would not open in Excel installed on Windows 7, Vista, XP, etc.
Furthermore, the file type icons that normally display next to familiar documents such as Excel were missing and a missing image red x was displayed.
The behavior of unrecognized File Types and missing document icons seemed to indicate an issue with the docIcon.xml configuration which is commonly located here: C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\14\TEMPLATE\XML.
However, after inspecting this file on each server I could find nothing apparently wrong. Finally, one last tedious inspection revealed the issue. Following the upgrade we had to reconfigure the Adobe PDF IFilter which meant adding the following key to the docIcon.xml file:
<Mapping Key="pdf" Value="pdficon_small.gif" />
After looking at this entry more closely I noticed that the double quotations marks looked italicized ". This meant the configuration contain extra characters and was most likely edit with an editor like word pad instead of note pad.
Tip: Never use Word Pad to edit configuration files because it will add additional characters and likely corrupt the configuration file.
I removed the unsupported double quotes and replaced them with unformatted double quotes. Viola, we could now open Excel and PDF Files again! Even better the cute little document type icons came back! :)
The reason the Excel Documents types became unavailable is because these document type mappings were located after the pdf file mapping within the docIcon.xml. Essential the invalid PDF entry broke all entries below it.
Hope this helps someone else!!!
posted @ Monday, June 7, 2010 9:54 AM | Feedback (2) |
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Saturday, May 22, 2010
Besides surviving countless beatings from my favorite two year old and a two hour crying fit from my 4 month old son I've attended several great community events. Thanks wifey :).
May 3rd: Oklahoma City Developers Group: Stop Drowning In Technical Debt! As the INETA Membership Mentor of Oklahoma I set a goal this year to try and encourage more collaboration between the strong communities existing in Tulsa and Oklahoma City. To accomplish this I have presented three times so far in OKC. On May 3rd I presented to a crowd of about 50 for the lunch meeting and 20 for the evening meeting. Both meetings were great.
May 4th: MSDN Events Launch 2010 Highlights – This event was well attend and provided overview demos of Windows 7, SharePoint 2010, SQL Server 2008 R2, Visual Studio 2010, Silverlight 4, etc.
May 13th: Tulsa SharePoint Interest Group: SharePoint 2010 Launch Event – For our May meeting we wanted to do something extra special. May 12th was the official launch of SharePoint 2010 and as a result we wanted to organize a Launch Event of our own. We held the event at Dave and Busters thanks to several general sponsors (K2, GDH Consulting, Metalogix, TEKSystems, The Rowland Group,
High Tech Resources). The event exceeded our expectations with about 50 people in attendance. We are also very thankful for Eric Shupps being our special guest speaker.
May 22nd: SQL Saturday 35 (Dallas) – I left Tulsa, OK at 3:30 in the morning to Drive down to Dallas where I met up with some friends including Shawn Weisfeld. I have never presented at a SQL Saturday before but the event is similar to other events such as code camps or SharePoint Saturdays which I regularly present at. I resented "SharePoint, A DBA's Nightmare!" to a room of about 40 people. The session was very conversational with some great questions. The goal of the presentation was to help the audience understand SharePoint's architecture a little better and know the pro/cons of certain decisions. We discussed such topics as database naming conventions, performance tips, and database maintenance.
posted @ Saturday, May 22, 2010 5:02 PM | Feedback (1) |
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C# & .NET Tutorials
Presentations & Training
Powered by:
Copyright © Dennis Bottjer


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Info About This Plugin:
Orginally I released this plugin under a different name, WP Smileys. I wanted to have smileys for my posts and comments form for me and anyone to use. I found WP Grins by Alex King from here, but it was some what limited. I really didn't like the default WordPress smilies and wanted to add more and better ones to the system. So that's when I wanted to try to hack together so type of mod to the WP Grins plugin and in the long run, created my very own plugin that doesn't resemble WP Grins at all! There are alot of features built into this plugin that just go beyond what WordPress and WP Grins has. First of all, all of the settings and options are set/managed via the Admin Panel, nothing at all is set in the plugins files so you don't have to worry about having to edit the file(s) and screwing anything up. If you really want to, you can though change the layout of your Smileys Popup Page by editing the lmbbox-smileys-popup.php file in the lmbbox-smileys folder, more directions are in the readme.txt and the plugin's files.
Using the LMB^Box Smileys Options Page, you can set the Minimum User Level to change and manage LMB^Box Smileys Settings, if to display Smileys in comments, if to add a button to the Comment Quicktags Toolbar (LMB^Box Comment Quicktags plugin), and what display settings for all of the Smileys Lists for both the Admin Write Pages and Comment Form Smileys Popup Page. In the LMB^Box Smileys Lists Management Page, you can set the path to the Smileys Images, the default Disabled Smiley Image, the Disabled Smiley Image Prefix, and you can add, edit, manage, and remove all of the Smileys Lists along with disabling any certain Smileys that you don't what to be used in either the Admin Write Pages or Comment Form.
Just a Note: If you turn off the display of a Smileys List or disable a Smiley in a Smileys List or have the Display Smileys in Comments set to 'No,' then WordPress and LMB^Box Smileys plugin will not process and display that Smiley(s) Image(s) in either the post (if Admin Write Pages) and/or the comment (Comment Form). The only thing that will be displayed is the Smiley(s) Tag Code. Also if you do set Display Smileys in Comments to 'No,' then no Smileys Button will be displayed in the Comment Quicktags Toolbar (if add button to Comment Quicktags Toolbar is 'Yes' and LMB^Box Comment Quicktags plugin is activated) but if you manually added a link to the Smileys Popup Page, then that link will still be there of course but it would open a popup window and display an error.
Latest Version!
I have just updated my LMB^Box Smileys plugin to version 3.2! This is the last of my house keeping updates for my plugins. Now LMB^Box Smileys validates XHTML 1.0 Transitional and has my new Plugin Version Notifier. The display code/layout and styles have been updated for the validation so please read the upgrade_readme.txt file for more details. This is from the readme.txt file in the Change Log section for 3.2:
Fixed Some Minor Code.
Updated Code/Layout.
Updated Styles.
Fixed Any Validation Problems, Now Validates XHTML 1.0 Transitional.
Added Plugin Version Notifier.
For more information and downloading, please see the WordPress Plugin Directory.
You may download the new plugin below:
LMB^Box Smileys Version 3.2
Old Versions!
Here are all of the old versions and releases of LMB^Box Smileys plugin. There really isn't that big of a need for this part but I'd like to keep all versions avalible to everyone. Below are the links to the archives:
LMB^Box Smileys Version 3.1
LMB^Box Smileys Version 3.0
LMB^Box Smileys Version 2.8
LMB^Box Smileys Version 2.7.2
LMB^Box Smileys Version 2.7.1
LMB^Box Smileys Version 2.7
LMB^Box Smileys Version 2.6
LMB^Box Smileys Version 2.5
LMB^Box Smileys Version 2.4
LMB^Box Smileys Version 2.3
LMB^Box Smileys Version 2.2
LMB^Box Smileys Version 2.1
Feel free to donate a little if you wish to and if you like what I've created. All donations would be wonderful and would help to keep all my plugins open source/free! To donate, click on the button below to use paypal. If you wish to donate via another form, please contact me. You may always just simply click on some of my sponsors' ads on the left side of the page! Thanks!
Plugin Feedback:
Now I'm done talking about my LMB^Box Smileys plugin and it's now time for you the reader and user to make the content. Please post comments below about any and all problems, ideas, thoughts, and feelings about my LMB^Box Smileys plugin. Thank you all for your support and help!


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Our lives are full of transitions: walking on our own, learning to drive, and selecting a college. Arriving for orientation begins your Sage journey. It will also be a very independent journey, one that you must create for yourself with the help and support of your family, friends, and all of the faculty and staff at The Sage Colleges.
Your time here at The Sage Colleges is precious; use it wisely, and be proactive with regard to your needs and dreams. Consider what you want to be a part of while you are here. Will you be active in athletics? How about community service? Do you want to be in an honors program? Are you looking for research opportunities? Does participation in student government interest you? It is up to you to ask questions, seek out information, and take full advantage of the programs, opportunities, presentations and more that will be offered during Orientation and beyond.


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Randomized Controlled Clinical Trial of CAD/CAM and Conventionally Fabricated Singl Implant Abutments.
|The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
|ClinicalTrials.gov Identifier: NCT01229995
Recruitment Status : Unknown
Verified October 2010 by Harvard School of Dental Medicine.
Recruitment status was: Active, not recruiting
First Posted : October 28, 2010
Last Update Posted : October 28, 2010
- Study Details
- Tabular View
- No Results Posted
- Disclaimer
- How to Read a Study Record
CAD/CAM technology has been introduced to the field of implant dentistry in the beginning of 1990's (Priest 2005). Since their introduction, the use of CAD/CAM technology in the production of dental implant restorations has been rapidly expanding. However, little evidence is currently present supporting its clinical viability (Henriksson 2003, Canullo 2007).
Therefore, the suggested prospective randomized study includes bone level placed Straumann implants restored with transmucosal elements and crowns fabricated using either CAD/CAM "Etkon" technology (Zirconia abutment and ceramic crown) or a conventional technique (Crossfit titanium abutment and a ceramometal crown).
The aim of this randomized controlled clinical trial is to examine single-tooth implant restorations in the esthetic zone. An esthetic area is defined as any area that is visible in the patient's full smile. [3rd ITI consensus conference 2004] The rehabilitations will be fabricated using two different techniques. Zirconia CAD/CAM (ZCC) implant restorations (tests) will be compared to Titanium conventionally-fabricated (TCF) implant restorations (controls) using, reproducible esthetic (objective/subjective) and biologic parameters.
This in vivo study is a randomized study with two groups of 15 patients with one implant each for a total of 30 patients and 30 implants. The implants will be examined for successful tissue integration according to the criteria of success (Buser et al. 1990) at every recall visit.
In addition, the following parameters will be evaluated for each restoration:
- Esthetic: A. Objective: PES/WES Score (Belser et al. 2009) from 1:1 digital photograph, study casts, and spectrophotometric measurements, and B. Subjective: VAS questionnaire for patients and VAS questionnaire from experts.
- Biologic (mPI, mB, simplified GI, microbial sample, periapical radiograph for DIB, and width of keratinized facial mucosa)
Finally, an evaluation of the mechanical, biologic and technical complications will be performed at every recall visit. Mechanical complications would be defined as those complications that involve the prosthesis such as abutment screw loosening, fracture of the veneer material, fracture of the crown framework, abutment screw fractures, and implant fractures. The category of biologic complications will include those complications that involve the soft tissues (e.g., fistula, suppuration, bleeding, gingival inflammation, and soft tissue dehiscence). Technical complications are defined as those related to restorative components and crowns (e.g. crown emergence profile, abutment and crown fit, screw loosening, ceramic fracture).
|Condition or disease
|Missing Teeth Teeth Replacemnt by Single Dental Implant Zirconia Abutment Titanium Abutment
|Device: dental implants - zirconia abutmetns - prefabricated abutments
|Not Applicable
|Study Type :
|Interventional (Clinical Trial)
|Actual Enrollment :
|30 participants
|Official Title:
|A Comparison of Zirconia CAD/CAM and Conventionally Fabricated Single Implant Abutments and Restorations in the Esthetic Zone: a Randomized Controlled Clinical Trial.
|Study Start Date :
|May 2009
|Active Comparator: Prefabricated Abutment
Device: dental implants - zirconia abutmetns - prefabricated abutments
- The aim of this randomized controlled clinical trial is to examine single-tooth implant abutments and restorations in the esthetic zone.
- Test group will achieve better biologic and esthetic outcomes when compared to control group
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.
|Ages Eligible for Study:
|21 Years and older (Adult, Older Adult)
|Sexes Eligible for Study:
|Accepts Healthy Volunteers:
Inclusion Criteria:
Inclusion Criteria:
- Age > 21 years
- Absence of relevant medical conditions
- Absence of periodontal diseases
- The opposing dentition must be natural teeth or fixed (not removable) restorations on teeth or implants.
- Availability for 5-year follow-up
- One missing tooth in the esthetic zone. An esthetic area is defined as any area that is visible in the patient's full smile. [3rd ITI consensus conference 2004]
- Presence of two intact adjacent teeth which are either non-restored or with minor restorations (small composite restorations)
- Adequate native bone to achieve primary stability
- Adequate band of keratinized mucosa (at least 2mm)
- Full Mouth Plaque Scores (FMPS) and Full Mouth Bleeding Scores (FMBS) < 25 %
Exclusion Criteria:
Exclusion criteria
- Heavy smokers (more than 10 cigarettes/day)
- Presence of conditions requiring chronic prophylactic use of antibiotics
- Medical conditions requiring prolonged use of steroids.
- History of radiation therapy to the head or neck or history of chemotherapy.
- Physical handicaps that would interfere with the ability to perform adequate oral hygiene.
- Patients with inadequate oral hygiene.
1. Adjacent implant 2. Presence of periapical radiolucencies at the adjacent teeth 3. Missing adjacent teeth 4. Local inflammation, including untreated periodontitis. 5. Persistent intraoral infections. 6. Untreated mucosal diseases.
To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT01229995
|Principal Investigator:
|German O. Gallucci, DMD Dr.Med.Dent.
|Harvard School of Dental Medicine
|Responsible Party:
|German O. Gallucci, Harvard School of Dental Medicine
|ClinicalTrials.gov Identifier:
|Other Study ID Numbers:
|First Posted:
|October 28, 2010 Key Record Dates
|Last Update Posted:
|October 28, 2010
|Last Verified:
|October 2010
Tooth Loss
Periodontal Diseases
Mouth Diseases
Stomatognathic Diseases
Tooth Diseases
Tooth Abnormalities
Stomatognathic System Abnormalities
Congenital Abnormalities


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Facebook Unveils New Feed
Facebook's Timeline update is aimed at replicating a personalized newspaper. George Stahl explains. Photo: Facebook.
This transcript has been automatically generated and may not be 100% accurate.
... I ... I'm not a lot of another redesign and Facebook just moments ago they help the defense wet ... but unveiled the new ... designs welcome to Digits I'm Simon Constable hit explain what went on ... George stall ... thanks for being a kid ... so um ... Facebook's goal to redesign ... but ... the bow to the eyes of the facade nervously because when they do this Namibia ... it has been a problem here and you know what did Facebook users don't like change and then said that's been consistent from from the earliest days of Facebook ... but this is that the changes as a base of the Newsfeed ... What did Facebook is doing as as Mark sucker for Teddy's China made the best crystallize newspaper app to to the stuff they you wanna see they're trying to highlight more this book in and try to do more with photos and videos see the breakdown was in a news feed by categories this is just one gets up from your closest friends or something like that ... and if there is video or photos to tax ... those are going to be ... bigger for the page and a more vibrant ... and that was old enough to that now ... as usual the seem to come out of nowhere that they didn't talk about that ... what you know we knew that there should be an event to be at any given the de tails of those suspected SNB from before the news feeds ... you know ... Facebook is a relatively young company is still less than a decade old and while its initial job of connecting people together it's done well since the beginning ... one thing that is has had to do over time as they run a business colleague goes with it and some changes that you're seeing now is helping Facebook to the buffet it did drop a better business model Newsfeed has become a very popular ... of money area for Facebook because their debt putting ads in an area ... it's not hard to see with better pictures and better video the UN is seeing ... ads like that in people's news feeds and that brings in more and my Facebook and is this going out with peers or a date when is one of the things that I think what we've read so it's all about around the offices of people some of ... our time ... aam of of Facebook is the still images with a sexy and ... that's really what Facebook is hoping to get it there is a certain level Facebook fatigue as every quarter this still prone to still get in a year and those numbers that rule number of users is more than ... PR hundred million people now on and that's that's huge ... aam but seven one billion people but um ... he noted there are people would be with him for while our son is so that it or you see in as much and again ... they're hoping that with ... changes like this than the speed and liked what he did to the search earlier this year by buying up ... I'd be their search powers on the site ... that people will stay with us a longer and do more with it ... or we shall say malls this year will be a ... consumer reaction as the yen has been in the past pretty up pretty interesting or what the changes going right away when mobile to take a few weeks Friday remarks was George Stahl I'm Simon Constable ...