Plastisol compositions that are essentially free of polyvinyl halides and phthalates
View Patent ↗Plastisol compositions are disclosed containing methacrylate core/shell copolymer, non-phthalate ester plasticizers, pigment, filler, and thixotropic agent. Other additives are optional. The plasticizer is a blend of dibenzoate and DINCH. The plastisol can be used an ink of various colors for use in application to textiles. The plastisol compositions avoid polyvinyl chloride polymer resins and phthalate plasticizers conventionally employed in plastisol inks.
1. A plastisol composition that is essentially free of polyvinyl halides and phthalate plasticizers, comprising:
(a) methacrylate core/shell copolymer;
(b) non-phthalate ester plasticizer comprising a blend of dibenzoate and di(isononyl)cyclohexane-1,2-dicarboxylate;
(c) pigment;
(d) filler; and
(e) thixotropic agent;
wherein the dibenzoate ester is selected from the group consisting of 2,2,4-trimethyl-1,3-pentanediyl dibenzoate, dipropylene glycol dibenzoate, and a blend of both, and wherein relative ratio of the dibenzoate to the di(isononyl)cyclohexane-1,2-dicarboxylate is determined by gelation temperature of the plastisol (G′/G″cross-over) in a parallel plate rheometer under conditions of a dynamic temperature ramp (3° C./min) occurring at a temperature between 79° C. and 89° C.
2. The plastisol composition according to claim 1 , wherein copolymer is PMMA-PBMA/PMMA core/shell copolymer.
3. The plastisol composition according to claim 2 , wherein the copolymer has a glass transition temperature of between 110° C. and 125° C. for the shell and a glass transition temperature of between 85° C. and 105° C. for the core.
4. The plastisol composition according to claim 3 , wherein a volume ratio of core to shell is in the range of 1:3 to 3:1.
5. The plastisol composition according to claim 4 , wherein the copolymer has a number average molecular weight ranges from 160,000 to 350,000.
6. The plastisol composition according to claim 5 , wherein a ratio of dibenzoate to di(isononyl)cyclohexane-1,2-dicarboxylate ranges from 9:1 to 4:6.
7. The plastisol composition according to claim 5 , wherein the pigment is titanium dioxide and wherein the thixotropic agent is selected from the group consisting of fumed silica, hydrogenated castor oil, and combinations thereof.
8. The plastisol composition of claim 7 , further comprising additives selected from the group consisting of dispersants, fillers, lubricants, optical brighteners, puff matting agents, antioxidants, chemical and physical blowing agents, stabilizers, moisture scavengers, air release agents, oxidizers, reducers, and combinations thereof.
9. The plastisol composition of claim 8 , wherein the plastisol composition in weight percent comprises:
Core/shell PMMA-
10-35
PBMA/PMMA
Copolymer
Plasticizer Blend of
20-45
Dibenzoate and
DINCH
Pigment(s)
10-40
Filler
5-20
Thixotropic Agent
1-25
Additives
0-40.
10. A method of making the plastisol composition of claim 1 , comprising the steps of:
(a) blending, into a mixture, methacrylate core/shell copolymer, non-phthalate ester plasticizer comprising a blend of dibenzoate and di(isononyl)cyclohexane-1,2-dicarboxylate, filler, and pigment, together using a rotary mixer with jacketed cooling tub until the mixture is homogeneous;
(b) de-agglomerating the mixture using a 3-roll mill, for a sufficient duration to ensure a Hegman fineness of grind value >6; and
(c) adding thixotropic agent,
wherein the dibenzoate ester is selected from the group consisting of 2,2,4-trimethyl-1,3-pentanediyl dibenzoate, dipropylene glycol dibenzoate, and a blend of both, and wherein relative ratio of the dibenzoate to the di(isononyl)cyclohexane-1,2-dicarboxylate is determined by gelation temperature of the plastisol composition (G′/G″ cross-over) in a parallel plate rheometer under conditions of a dynamic temperature ramp (3° C./min) occurring at a temperature between 79° C. and 89° C.
11. A textile article having an image graphic printed thereon from the plastisol composition of claim 1 .
12. The plastisol composition of claim 1 , in the form of an image graphic printed on a textile article.
13. The plastisol composition according to claim 12 , wherein the image graphic of plastisol is applied by a screen-printing technique on the textile article.
14. The plastisol composition according to claim 12 , wherein the copolymer is PMMA-PBMA/PMMA core/shell copolymer.
15. The plastisol composition according to claim 12 , wherein a ratio of dibenzoate to di(isononyl)cyclohexane-1,2-dicarboxylate in the non-phthalate ester plasticizer ranges from 9:1 to 4:6.
16. The plastisol composition according to claim 1 , wherein the copolymer has a glass transition temperature of between 110° C. and 125° C. for the shell and a glass transition temperature of between 85° C. and 105° C. for the core.
17. The plastisol composition according to claim 16 , wherein a volume ratio of core to shell is in the range of 1:3 to 3:1.
18. The plastisol composition according to claim 17 , wherein the copolymer has a number average molecular weight ranges from 160,000 to 350,000.