Vinyl chloride-based resin latexes, processes for producing the same, and thermal transfer image-receiving sheet obtained using the same
A vinyl chloride-based resin latex which froths little when unreacted monomer remaining in the latex are recovered under heat and reduced-pressure conditions, and a thermal transfer image-receiving sheet which has satisfactory water resistance, does not yellow during storage, and gives images having excellent durability and light resistance. The invention provides a vinyl chloride-based resin latex contains a copolymer containing a vinyl chloride and an epoxy-group-containing vinyl or contains vinyl chloride, an epoxy-group-containing vinyl, and a carboxylic acid vinyl ester, wherein a content of the epoxy-group-containing vinyl is 0.1% by weight or more but less than 3% by weight, and wherein the latex contains no surfactant, and has a solid concentration of 25% by weight or more; a process for producing the latex; and a thermal transfer image-receiving sheet obtained using the latex.
1. A vinyl chloride-based resin latex, comprising a copolymer comprising vinyl chloride and an epoxy-group-comprising vinyl,
wherein:
a content of the epoxy-group-comprising vinyl in the copolymer is 0.1% by weight or more but less than 3% by weight;
the resin latex comprises no surfactant and has a solid concentration of 25% by weight or more; and
the vinyl chloride-based resin latex is produced by a process comprising:
polymerizing a vinyl chloride monomer and an epoxy-group-comprising vinyl monomer in the presence of a polymerization initiator in an aqueous medium comprising water and no surfactant, wherein an amount of the epoxy-group-comprising vinyl monomer is 0.1% by weight or more but less than 3% by weight, based on a sum of the vinyl chloride monomer and the epoxy-group-comprising vinyl monomer,
wherein a weight ratio of the vinyl chloride monomer and the epoxy-group-comprising vinyl monomer to the water is ⅓ or greater and that part or the whole of the epoxy-group-comprising vinyl monomer is added in portions or continuously to the aqueous medium during the polymerization.
2. The resin latex of claim 1 , wherein the epoxy-group-comprising vinyl is glycidyl methacrylate or allyl glycidyl ether.
3. A process for producing the vinyl chloride-based resin latex of claim 1 , the process comprising:
polymerizing a vinyl chloride monomer and an epoxy-group-comprising vinyl monomer in the presence of a polymerization initiator in an aqueous medium comprising water and no surfactant, wherein an amount of the epoxy-group-comprising vinyl monomer is 0.1% by weight or more but less than 3% by weight, based on a sum of the vinyl chloride monomer and the epoxy-group-comprising vinyl monomer,
wherein a weight ratio of the vinyl chloride monomer and the epoxy-group-comprising vinyl monomer to the water is ⅓ or greater and that part or the whole of the epoxy-group-comprising vinyl monomer is added in portions or continuously to the aqueous medium during the polymerization.
4. The process of claim 3 , wherein a part of the vinyl chloride monomer is added in portions or continuously to the aqueous medium during the polymerization.
5. The process of claim 3 , wherein the monomers are polymerized in the presence of at least one selected from the group consisting of a chain transfer agent and a reducing agent.
6. A vinyl chloride-based resin latex composition, comprising the vinyl chloride-based resin latex of claim 1 .
7. A vinyl chloride-based resin powder obtained by drying the vinyl chloride-based resin latex of claim 1 .
8. A vinyl chloride-based resin composition, comprising:
the vinyl chloride-based resin powder of claim 7 ; and
an organic solvent.
9. A vinyl chloride-based resin latex, comprising
a copolymer comprising vinyl chloride, an epoxy-group-comprising vinyl, and a carboxylic acid vinyl ester,
wherein:
a content of the epoxy-group-comprising vinyl in the copolymer is 0.1% by weight or more but less than 3% by weight;
the resin latex comprises no surfactant and has a solid concentration of 25% by weight or more; and
the vinyl chloride-based resin latex is produced by a process comprising:
polymerizing a vinyl chloride monomer, an epoxy-group-comprising vinyl monomer, and a carboxylic acid vinyl ester monomer in the presence of a polymerization initiator in an aqueous medium comprising water and no surfactant, wherein an amount of the epoxy-group-comprising vinyl monomer is 0.1% by weight or more but less than 3% by weight, based on the sum of the vinyl chloride monomer, the epoxy-group-comprising vinyl monomer, and the carboxylic acid vinyl ester monomer,
wherein a weight ratio of the vinyl chloride monomer, the epoxy-group-comprising vinyl monomer, and the carboxylic acid vinyl ester monomer to the water is ⅓ or greater and that part or the whole of the epoxy-group-comprising vinyl monomer is added in portions or continuously to the aqueous medium during the polymerization.
10. The resin latex of claim 9 , wherein the carboxylic acid vinyl ester is vinyl acetate.
11. The resin latex of claim 10 , wherein the epoxy-group-comprising vinyl is glycidyl methacrylate or allyl glycidyl ether.
12. A process for producing the vinyl chloride-based resin latex of claim 9 , the process comprising:
polymerizing a vinyl chloride monomer, an epoxy-group-comprising vinyl monomer, and a carboxylic acid vinyl ester monomer in the presence of a polymerization initiator in an aqueous medium comprising water and no surfactant, wherein an amount of the epoxy-group-comprising vinyl monomer is 0.1% by weight or more but less than 3% by weight, based on the sum of the vinyl chloride monomer, the epoxy-group-comprising vinyl monomer, and the carboxylic acid vinyl ester monomer,
wherein a weight ratio of the vinyl chloride monomer, the epoxy-group-comprising vinyl monomer, and the carboxylic acid vinyl ester monomer to the water is ⅓ or greater and that part or the whole of the epoxy-group-comprising vinyl monomer is added in portions or continuously to the aqueous medium during the polymerization.
13. The process of claim 12 , wherein a part of the vinyl chloride monomer is added in portions or continuously to the aqueous medium during the polymerization.
14. The process of claim 12 , wherein the monomers are polymerized in the presence of a chain transfer agent, a reducing agent, or a chain transfer agent and a reducing agent.
15. The resin latex of claim 9 , wherein the epoxy-group-comprising vinyl is glycidyl methacrylate or allyl glycidyl ether.
16. A vinyl chloride-based resin latex composition, comprising the vinyl chloride-based resin latex of claim 9 .
17. A vinyl chloride-based resin powder obtained by drying the vinyl chloride-based resin latex of claim 9 .