Thermoplastic ink composition for decorating glass, glass-ceramic, and ceramic ware

Claim 1

A thermoplastic ink suitable for decorating glass, glass-ceramic, and ceramic articles exhibiting pressure sensitivity at temperatures substantially below its Ring and Ball softening point prepared from a formulation consisting essentially, in weight percent, of: (a) about 50-80% of a vitrifiable, inorganic flux containing up to about 30% by weight inorganic pigments and opacifiers; (b) about 2-20% of an ethylene-ester copolymer resin having about 8-40% by weight of a copolymerized ester selected from the group consisting of vinyl alcohol esters of C 1 -C 4 saturated monocarboxylic acids and C 1 -C 5 saturated alcohol esters of acrylic or methacrylic acid, the molecular weight of the polymer being such as to yield a melt index, as defined by ASTM D1238, of about 20-400 g/10 minutes; (c) about 4-20% of an amorphous tackifying resin having a Ring and Ball softening point of about 40°-110° C.; (d) 0-10% of a modifying polyolefin resin selected from the group consisting of a low molecular weight polyethylene resin with a melt index, as defined by ASTM D1238, greater than about 20 g/10 minutes and an amorphous polypropylene resin having a melt viscosity of about 500-15,000 cps at 375° F. (˜191° C.); and (e) about 5-25% of an organic wax and/or plasticizer compatible with the resins of paragraphs (b), (c), and (d) and having a Ring and Ball softening point of less than about 100° C.