The reference materials, which are structurally at least  peripherally related to the instant test materials and are  soluble in both water and 1: 1 acetonitrile:chloroform, are  used to make a calibration plot in the non-aqueous titration  (1: 1 acetonitrile:chloroform solvent and 0.lN perchloric  A  basecoat pigmented with a mixture of Pigment Red 177  and mica is stabilized with 1 % by weight of a hindered  Stabilization of Pigmented Automotive OEM  Basecoat  In order to determine the  pKa  values of water insoluble  material organic references with known  pKa  values in water  are titrated non-aqueously. A plot of the half neutralization  potential  (HNP)  versus the known aqueous  pKa  value of the  reference material is establed. The  HNP  of the test material  is determined and extrapolated to find the corresponding  pKa  value of the test material. Such organic reference  materials include 2,2,6,6-tetramethylpiperidine; 4-hydroxy- 2,2,6,6-tetramethylpiperidine; 1-hydroxyethy 1-4-hydroxy-2,  2,6 ,6-tetramethy lpi peridine; triace tone amine and  N-methylaniline.  pKa  Values  The materials containing the instant compounds exhibit  stability against deleterious effects of UV light and thermal  exposure.  The instant hindered amine compounds substituted on the  N-atom with an  -O-E-OH  moiety provide better stabiliza› tion efficacy to the sections in respect to visual appearance,  gloss retention, resistance to color change and to delamina› tion than do the corresponding  -NOR  compounds lacking  such a hydroxyl moiety.  The coated board sections are allowed to dry at ambient  temperature for two weeks, then evaluated for visual  appearance, gloss and Hunter L *, a* and b* color. The  sections are exposed on racks at a 45°  angle in South Florida  for six months before being returned and evaluated for  visual appearance, gloss, color change and any other signs of  degradation or delamination.  Each coating is brush applied onto 6"x6" sections of cedar  and pine boards. The weight of the coating applied is  regulated by weighing the coating and brush before and after  application and ensuring that the same weight of coating is  applied to each section.  The pelletized fully formulated resin is then processed  into a useful article such as extrusion into sheet, film, profile  and pipe; molded into bottles; injection molded into a  molded article; thermoformed into molded articles; or rota- tional molded into hollow articles.  Thermoplastic materials composed of mixtures of copoly› mers derived from the copolymerization of styrene mono- mer with acrylonitrile and the copolymerization of stryrene  monomer with butadiene, generally referred to as  ABS,  are  dry blended with the instant compounds and melt com› pounded into pellets. Typical formulations contain the  instant compounds at levels from 0.05% to 2.0%, a metal  stearate such as calcium stearate at 0.05% to 0.5%, pigments  from 0% to 5%, UV absorbers at levels of 0.05% to 2.0%,  phosphites at 0.0%-0.1 %, phenolic antioxidants at  0.0%-1.25%, N,N-dialkylhydroxylamine at 0.0%-0.1 %,  and optionally other hindered amine stabilizers at levels of  0.0% to 2.0%.  ABS  Molding Applications  0.45 gram of the test stabilizer is predissolved in 10 g of  the cosolvent blend which is then incorporated into the  following composition:  The test stabilizers are incorporated into a waterborne  dispersion by predissolution in a cosolvent blend. The  waterborne dispersion is a commercially available acrylic/  urethane hydrid resin. The cosolvent blend is a 1:1 mixture  of TEXANOLfi (2,2,4-trimethyl-1,3-pentanediol, Texaco)  andARCOSOLVEfi TPM (tripropylene glycol methyl ether,  AtlanticRichfield).  Waterborne coating comprise a significant and increasing  proportion of the coating in use for a wide variety of  applications including automotive basecoats, industrial coat› ings and trade sale coatings. These coatings may be pig› mented or transparent. The trends are also towards higher  solids formulation which in general depend on light stabi› lizers to maintain properties on exterior exposure, and  towards lower levels of cosolvents. This requires higher  solubility of stabilizers in such cosolvents (primarily water)  or actual solubility in water.  Stabilization of Waterborne Wood Varnish  The instant hindered amine compounds substituted on the  N-atom with an  -O-E-OH  moiety provide better stabiliza- tion efficacy to the panels in respect to distinctness of image,  gloss retention and resistance to color change than do the  corresponding  -NOR  compounds lacking such a hydroxyl  moiety.  20°  Gloss, Distinctness of Image, Hunter Color Space  Values (L *, a*, b* and li.E) are measured before exposure  and after 3000 hours of exposure.  Irradiance: 0.55 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.  amine stabilizer based on the total basecoat solids (pigment  plus resin). The basecoat is spray applied at a dry film  thickness of 1 mil (25 microns) to primed 4"x12" steel  panels, then topcoated with a high solids commercially  available automotive clearcoat. The coated panels are cured  in an over at 250°  F.  (121 °  C.) for 30 minutes. The panels are  then exposed in a Xenon-Arc Weather-Ometer under the  following conditions:  hydroxyl moiety, a higher percent recovery of the instant  hindered amine compound from the clearcoat over a plastic  substrate is found indicating that much less of the instant  hindered amine stabilizer migrates into the plastic substrate  allowing for better stabilization of the clear topcoat over  such plastic substrates.  75  US 6,872,832 B2  76  EXAMPLE 111  EXAMPLE 113  EXAMPLE 114  EXAMPLE 112  FLEXTHANE  fi  630 (Air Products)  Foamaster VF  Water  TEXANOL/ARCOSOLVE/hindered  amine  UV absorber (TINUVIN  fi  1130, Ciba)  BYK 346  MICHEMLUBE  fi  162  ppw  100.0  0.1  10.0  10.5  1.2  0.5  2.0 