63  US 6,391,949 B2  64  EXAMPLE  106  EXAMPLE 107  EXAMPLE 108  EXAMPLE 101  EXAMPLE 102  EXAMPLE 103  EXAMPLE 105  EXAMPLE 104  The title compound is prepared from the reaction of  approximately equimolar amounts of the compound pre- pared in Example 16A with hexamethylene diisocyanate  followed by reaction with excess methanol.  Condensation Product of 4-Hydroxy-l-(2-hydroxy- 2-methylpropoxy)-2,2,6,6-tetramethylpiperidine  with Hexamethylene Diisocyanate, and Terminated  with Methoxy  l-(2-Hydroxy-2-methylpropoxy)4-[ 4-(methoxy› carbonyl)butyryloxy ]-2,2,6,6-tetramethylpiperidine  The title compound is made the procedure of Example  101 where dimethyl sebacate is replaced by an equivalent  amount of dimethyl glutarate.  The title compound is made by the procedure of Example  101 where dimethyl sebacate is replaced by an equivalent  amount of dimethyl succinate.  1-(2-H ydroxy-2-methylpropoxy )-4-[3-( methoxy› carbony l)propiony loxy ]-2,2,6,6- tetramethylpiperidine  20°  Gloss is measured before exposure and at 500 hour  intervals during exposure. Higher gloss retention is desir› able.  Irradiance: 0.45 watts per square meter.  Lamp filters are: quartz inner/borosilicate S outer.  Cam 180 cycle: 40 minutes light only; 20 minutes light  and front spray; 60 minutes light only; 60 minutes dark and  rear spray condensate.  Steel panels 3"x4" primed with an electrocoat primer are  then coated with a light blue metallic basecoat, then with the  stabilized clearcoat. The basecoat is spray applied to a  thickness of 1.0 mil (25 microns) dry film thickness and the  stabilized clearcoat is then applied to a thickness of 2.0 mils  (50 microns) dry film thickness. The coating is air-dried and  aged for two weeks. The panels are then exposed in a  Xenon-Arc Weather-Ometer under the following conditions:  The hindered amine test stabilizers are incorporated into  a two-component acrylic urethane coating as described om  Example 99. The system is catalyzed with 0.02% by weight  of dibutyltin dilaurate based on the total resin solids. The  stabilizers are added at the appropriate level to the acrylic  polyol portion of the two-component coating which is then  combined with the isocyanate component immediately prior  to application.  Stabilization of a Two-Component Acrylic  Urethane Clearcoat  The title compound is made by the procedure of Example  101 where dimethyl sebacate is replaced by an equivalent  amount of dimethyl adipate.  1-(2-Hydroxy-2-methylpropoxy)-4-[5-(methoxy› carbonyl)pentanoyloxy ]-2,2,6,6- tetramethylpiperidine  The title compound is prepared by the reaction of the  compound prepared in Example 16A with one equivalent or  more of dimethyl sebacate and a catalytic amount of lithium  amide in xylene.  1-(2-H ydroxy-2-methylpropoxy )-4-[9-( methoxy› carbony l)nonanoy loxy ]-2,2,6,6- tetramethylpiperidine  The title compound is prepared from the reaction of  approximately equimolar amounts of the compound pre› pared in Example 74 with hexamethylene diisocyanate,  followed by reaction with excess methanol.  Condensation Product of 4-Hydroxy-1-(2-hydroxy› l-phenethoxy )-2,2,6,6-tetramethy lpiperidine with  Hexamethylene Diisocyanate, and Terminated with  Methoxy  These data show that the instant compound having a  hydroxy moiety present on the group attached to the  1-position of the hindered amine provides excellent solubil- ity and compatibility for the polyester urethane coating that  cannot be achieved with the closest prior art compound  where said hydroxy moiety is absent.  The title compound is prepared from the reaction of  approximately equimolar amounts of the compound pre- pared in Example 70 with hexamethylene diisocyanate,  followed by reaction with excess methanol.  Condensation Product of 4-Hydroxy-l-(2- hydroxyethoxy)-2,2,6,6-tetramethylpiperidine with  Hexamethylene Diisocyanate, and Terminated with  Methoxy  *  A is unstabilized.  B contains 2% by weight of bis(l-octyloxy-2,2,6,6-tetramethylpiperidin-4- yl) sebacate  (TINUVIN  fi  123).  C contains 2% by weight of bis[l-(2-hydroxy-2-methylpropoxy)-2,2,6,6- tetramethylpiperidin-4-yl] sebacate, compound of Example 2.  Solidified Coating in Jar  Sample*  A  B  C  0  clear  clear  clear  Day 1  clear  cloudy  clear  Day 2  clear  cloudy  clear  18 months  clear  cloudy  clear  Percent Retention of 20°  Gloss  Sample*  4500 hours  8500 hours  12000 hours  A  17  B  C  D  E  60  22  47  17  34  22  41  23 