Dec. 11, 2014  25  US 2014/0364548 Al  [0472]  The inks of examples 1-11 according to the present  invention showed excellent reliability and good print quality  on machine coated or offset coated media.  [0473]  Detailed embodiments of the present invention are  disclosed herein; however, it is to be understood that the  disclosed embodiments are merely exemplary of the inven› tion, which can be embodied in various forms. Therefore,  specific structural and functional details disclosed herein are  not to be interpreted as limiting, but merely as a basis for the  claims and as a representative basis for teaching one skilled in  the art to variously employ the present invention in virtually  and appropriately detailed structure. In particular, features  presented and described in separate dependent claims may be  applied in combination and any combination of such claims  are herewith disclosed.  1.  Ink composition, suitable for being ejected from an  inkjet marking device at an operating temperature of between  15°  C. and 50°  C., the ink composition comprising:  1-40 weight % of a water-dispersible resin;  0.5-15 weight% ofa water-dispersible colorant;  20-80 weight % water;  0-75 weight% of a cosolvent;  0.01-3 weight% of a mixture of surfactants comprising at  least one surfactant of a first type being an ethoxylated  acetylene glycol and at least one surfactant of a second  type selected from the group consisting of silicone sur› factants and fluorochemical surfactants;  wherein all amounts are relative to the total ink composition,  and wherein the ink composition has a dynamic surface ten› sion of below 35 mN/m measured at 10 Hz and a static surface  tension measured at 0.1 Hz of above 21 mN/m both deter› mined at the operating temperature with the bubble pressure  method, wherein the amount of the mixture of surfactants is  sufficient to obtain said dynamic and static surface tensions.  2.  The ink composition according to claim  1,  wherein the  ink composition has a static surface tension of below 30  mN/m.  3.  The ink composition according to claim  1,  wherein the  ethoxylated acetylene glycol has a general structure satisfy› ing the formula below:  wherein R$_{1 }$ and R$_{4 }$ are the same or different alkyl radicals  having from 3-10 carbon atoms and R$_{2 }$ and R$_{3 }$ are the same or  different and selected from methyl and ethyl and x and y are  both integers and have a sum in the range of3 to 60.  4.  The ink composition according to claim  3,  wherein R$_{1 }$ and R$_{4 }$ are the same alkyl radicals having from 3-6 carbon  atoms and R$_{2 }$ and R$_{3 }$ are methyl.  5.  The ink composition according to claim  1,  wherein the  surfactant of the first type is an ethoxylated acetylene glycol,  selected from the group consisting of ethoxylated 3-methyl› l-nonyn-3-ol, ethoxylated 7, 10-dimethyl-8-hexadecyne-7,  10-diol,  ethoxylated  4, 7-dimethyl-5-decyne-4, 7-diol,  ethoxylated 2,4, 7,9-tetramethyl-5-decyne-4, 7-diol, ethoxy› lated 2,5,8,11-tetramethyl-6-dodecyne-5,8-diol, and combi› nations thereof.  $^{4}$>not determined  [0461]  Table 5 shows that the latex ink compositions  according to Examples 5, 6, 9, 10 and 11 showed an actual  dotgain of 2.5 or higher on a wide range of media:  [0462]  Example 5: six out of seven tested media;  [0463]  Example 6: five out of seven tested media;  [0464]  Example 9: four out of four tested media. The dot› gains of the ink according to example 9 on TCP Gloss, Hello  Matt and Mitsubishi MD 1084 have not been determined.  [0465]  Therefore, at least four out of the total of seven  media showed a dotgain above 2.5;  [0466]  Example 10: four out of four tested media (i.e. at  least four out or seven media);  [0467]  Example 11: three out of six tested media (i.e. at  least three out of seven media, but at most four out of seven  media).  [0468]  With the ink according to Comparative Example A,  three coated media out of seven tested media showed an  actual dotgain of 2.5 or higher. Therefore, the range of media  on which an ink according to the present invention has been  printed, which has lead to a dotgain of 2.5 or higher (e.g.  Examples 5, 6, 9, 10 and 11) is equal to or larger than inks  according to the prior art ( e.g. Comparative Example A).  [0469]  Table 5 shows that the latex ink composition accord› ing to example 5, comprising 1 weight% Dynol 607, shows a  dotgain of 2.8 or higher for four of the seven tested media,  while the inks according to Comparative Example A (no  Dynol 607) and example 6 (2 weight% Dynol 607) only show  a dotgain of 2.8 or higher on one and two of the seven tested  media, respectively.  [0470]  The ink composition according to example 9 (0.87  weight% Dynol 607) shows an actual dotgain of above 2.8 for  one of the four tested media. The ink according to this  example comprises a polymeric cosolvent (PEG 600) which  thickens the ink during drying.  [0471]  FIG.  2  shows the drying behavior of the inks of  Comparative Example A (ink X in FIG.  2,  curve 2) and  Example 9 (ink Y in FIG.  2,  curve 3). FIG.  2  shows the  viscosity (y-axis) as a function of the drying time (x-axis).  FIG.  2  clearly shows that an ink containing a polymeric  cosolvent (ink Y) shows a faster viscosity increase over time  than inks comprising monomeric cosolvents (ink X). The ink  according to example 6 may be considered as a "viscously  thickening ink". The thickening behavior limits the spreading  of printed ink drops upon drying and hence prevents or at least  mitigates coalescence and image bleeding. The decrease in  coalescence level is indicated with arrow 4.  TABLE 5-continued  Actual dotgain of inks according to Comparative Example (CE) A,  examples (Ex.) 5, 6, 9, 10 and 11 on a range ofreceiving media  Medium  CEA  Ex. 5  Ex. 6  Ex.9  Ex. 10  Ex.11  Top  2.42  2.67  2.67  2.65  n.d. $^{4}$>  2.4  CoatedPlus  Gloss (TC+)  Top Coated  2.45  2.87  2.78  n.d. $^{4}$>  2.6  2.3  Pro Gloss  (TCP Gloss)  Hello Matt  2.59  3.12  3.19  n.d. $^{4}$>  3.1  2.6  Top Coated  2.65  3.11  2.63  2.86  n.d. $^{4}$>  2.6  Pro Silk  (TCproS)  Mitsubishi  2.29  2.46  2.47  n.d. $^{4}$>  n.d. $^{4}$>  n.d. $^{4}$>  MD1084 