| 摘要 |
The coating compositions of the parent Specification, containing ethyl cellulose, mineral oil and a plasticizer, are improved or modified by employing weight ratios between 1:1,25 and 2,0:1 ethyl cellulose to plasticizer, between 1,2:1 and 2,7:1 mineral oil to ethyl cellulose and between 1,8:1 and 3,9:1 mineral oil to plasticizer, the proportions being such that the hot melt viscosity of the composition at 320 DEG F. is between 500 and 10,000 cps. The composition may include also up to 5% by weight of a wax ingredient melting above 100 DEG F., such as a parafin wax, carnauba or beeswax. A specified plasticizer includes castor oil together with an acetylated mono-glyceride, glycerol mono-oleate and epoxidized soya bean oil; many others are listed. Specified antioxidants include butylated hydroxyanisole, 2, 6-di-tertiary butyl-4-methyl phenol, and 2, 2-thio bis (4-methyl-6-tertiary butyl-phenol). Colour stabilizers may comprise citric or tartaric acid, or tricresyl phosphite. Reference has been directed by the Comptroller to Specifications 832,449, 837,410 and 840,154.ALSO:The coating compositions of the parent Specification are improved or modified by employing weight-ratios between 1 : 1 : 25 and 2.0 : 1 ethyl cellulose to plasticizer, between 1.2 : 1 and 2.7 : 1 mineral oil to ethyl cellulose and between 1.8 : 1 and 3.9 : 1 mineral oil to plasticizer in the composition such that its hot melt viscosity at 320 DEG F. is between 500 and 10,000 c.p.s. The composition may include also up to 5% by weight of a wax ingredient melting above 100 DEG F., such as a paraffin wax. Reference has been directed by the Comptroller to Specifications 832,449, 837,410 and 840 154. |
