Printing ink composition and method for printing

A process for applying at least one color image to an elastic surface of a thermoplastic rubber or polymer compound formed into a toy, ball, household item, sheet or film article, which have a flexible and resilient surface structure receptive to at least one applied printing ink, comprising:

• (A) selecting the compound from one of a polymer and rubber elastomer and thermoplastic rubber compounds, and
• including about 1% to about 95% by weight of mineral oil;
• (B) applying a printing ink composition to the elastic surface of the formed article,
• said printing ink composition comprising:
• at least one styrenic copolymer resin selected from the group consisting of diblock copolymer, triblock copolymer, radical block copolymer, and multi-block copolymers, said styrenic copolymer resin included in approximately 1% to 30% by weight of the printing ink composition, and selected from the group consisting of styrene-butadine rubber, styrene-butadine-styrene, and styrene-ethylene-butadine-styrene;
• and
• including mineral oil within the printing ink composition of between about 1% to about 30% by weight of said composition;
• including solvents between about 30% to about 80% by weight of said composition, said solvents being at least one of an aromatic hydrocarbon, ester, glycol ester acetate, and ketone;
• including at least one colorant between about 5% to about 60% by weight of the printing ink composition, said colorant including at least one of an organic pigment, an inorganic pigment, a luminescent pigment, a florescent pigment, and thermochromatic pigment;
• an additive to adjust the application characteristic of the printing ink, and to maintain its structural integrity after printing upon the surface of the thermoplastic rubber or polymer compound even as it is stretched, said additive being at least one of:
• an adhesion modifier,
• a flow control agent comprising polyether modified polydimethylsiloxane,
• an antioxidant comprising pentaerythrityl tetra-di-t-butyl hydroxyhydrocinnamate,
• a wetting agent comprising one of dioctyl sodium sulfosuccinate and polyether modified siloxane,
• an antifoaming agent comprising one of alkylmethyl siloxane, polysiloxanes, and hydrophobic solids in polyglycol, and
• an antistatic agent comprising alkylamine ethoxylate.

The process for applying at least one color image to an elastic surface of a thermoplastic rubber or polymer compound, including:

• applying a transparent top coat to the surface of said compound after applying said printing ink composition, said top coat being applied as a film ranging from 0.01 to 10 millimeters thick,
• said top coat having at least one styrenic copolymer resin applied in an approximate amount of 1% to about 30% by weight of the top coat, and said resin selected from the group consisting of styrene-butadiene-styrene polymers, styrene-ethylene-propylene polymer, styrene-ethylene-butadiene-styrene polymers, styrene-ethylene-ethylene/propylene-styrene polymers,
• said top coat including mineral oil being between 1% to about 30% by weight of said top coat, said top coat including at least one solvent being between about 30% to about 80% by weight of said top coat composition, and including one of aromatic hydrocarbon, ester, glycol ether acetate and ketone, and
• wherein said top coat forms a stretch film sealing said printed image to said compound and preventing said image from peeling off said surface when scratching of said surface occurs;
• and
• wherein the applied image remains intact upon the surface of the compound when stretched.