Composition for injection molding, sintered compact, and method for producing sintered compact

Patent metadata

Field	Value
Publication number	US-9249292-B2
Application number	US-201213688855-A
Country	US
Kind code	B2
Filing date	Nov 29, 2012
Priority date	Nov 30, 2011
Publication date	Feb 2, 2016
Grant date	Feb 2, 2016

Abstract

A composition for injection molding includes: an inorganic powder composed of at least one of a metal material and a ceramic material; and a binder containing a polyacetal-based resin and an ethylene-glycidyl methacrylate-based copolymer. In the composition, the ethylene-glycidyl methacrylate-based copolymer is contained in an amount of 1% by mass or more and 30% by mass or less with respect to the amount of the polyacetal-based resin.

First claim

What is claimed is:

1. A composition for injection molding, comprising:
an inorganic powder composed of at least one of a metal material and a ceramic material; and
a binder containing a polyacetal-based resin and an ethylene-glycidyl methacrylate-based copolymer,
wherein the ethylene-glycidyl methacrylate-based copolymer is contained in an amount of 1% by mass or more and 30% by mass or less with respect to the polyacetal-based resin; and
the polyacetal-based resin is a copolymer of formaldehyde and a comonomer other than formaldehyde.

2. The composition for injection molding according to claim 1 , wherein the composition has:
an inner layer composed mainly of the ethylene-glycidyl methacrylate-based copolymer and covering each particle of the inorganic powder, and
an outer layer composed mainly of the polyacetal-based resin and located outside the inner layer.

3. The composition for injection molding according to claim 1 , wherein the ethylene-glycidyl methacrylate-based copolymer contains at least one of vinyl acetate and methyl acrylate as a monomer constituting the copolymer.

4. The composition for injection molding according to claim 1 , wherein the softening point of the ethylene-glycidyl methacrylate-based copolymer is 65° C. or higher and 105° C. or lower.

5. The composition for injection molding according to claim 1 , further comprising a saturated fatty acid.

6. The composition for injection molding according to claim 1 , further comprising a wax.

7. A sintered compact, which is produced using the composition for injection molding according to claim 1 .

8. A composition for injection molding, comprising:
an inorganic powder composed of at least one of a metal material and a ceramic material; and
a binder containing a polyacetal-based resin and an ethylene-glycidyl methacrylate-based copolymer,
wherein the ethylene-glycidyl methacrylate-based copolymer is contained in an amount of 1% by mass or more and 30% by mass or less with respect to the polyacetal-based resin; and
wherein the composition has an inner layer composed mainly of the ethylene-glycidyl methacrylate-based copolymer and covering each particle of the inorganic powder, and an outer layer composed mainly of the polyacetal-based resin and located outside the inner layer.

9. The composition for injection molding according to claim 8 , wherein the polyacetal-based resin is a copolymer of formaldehyde and a comonomer other than formaldehyde.

10. The composition for injection molding according to claim 8 , wherein the ethylene-glycidyl methacrylate-based copolymer contains at least one of vinyl acetate and methyl acrylate as a monomer constituting the copolymer.

11. The composition for injection molding according to claim 8 , wherein the softening point of the ethylene-glycidyl methacrylate-based copolymer is 65° C. or higher and 105° C. or lower.

12. The composition for injection molding according to claim 8 , further comprising a saturated fatty acid.

13. The composition for injection molding according to claim 8 , further comprising a wax.

14. A composition for injection molding, comprising:
an inorganic powder composed of at least one of a metal material and a ceramic material; and
a binder containing a polyacetal-based resin and an ethylene-glycidyl methacrylate-based copolymer,
wherein the ethylene-glycidyl methacrylate-based copolymer is contained in an amount of 1% by mass or more and 30% by mass or less with respect to the polyacetal-based resin; and
wherein the ethylene-glycidyl methacrylate-based copolymer contains at least one of vinyl acetate and methyl acrylate as a monomer constituting the copolymer.

15. The composition for injection molding according to claim 14 , wherein the composition has:
an inner layer composed mainly of the ethylene-glycidyl methacrylate-based copolymer and covering each particle of the inorganic powder, and
an outer layer composed mainly of the polyacetal-based resin and located outside the inner layer.

16. The composition for injection molding according to claim 14 , wherein the polyacetal-based resin is a copolymer of formaldehyde and a comonomer other than formaldehyde.

17. The composition for injection molding according to claim 14 , wherein the softening point of the ethylene-glycidyl methacrylate-based copolymer is 65° C. or higher and 105° C. or lower.

18. The composition for injection molding according to claim 14 , further comprising a saturated fatty acid.

19. The composition for injection molding according to claim 14 , further comprising a wax.

Assignees

• Seiko Epson Corp

Inventors

• Hamakura Nobuyuki
• Nakamura Hidefumi

Classifications

• B22F1/10

  Metallic powder containing lubricating or binding agents; Metallic powder containing organic material · CPC title

• C08L59/00 Primary

  Compositions of polyacetals; Compositions of derivatives of polyacetals (of polyvinyl acetals C08L29/14) · CPC title

• C04B35/10

  based on aluminium oxide · CPC title

• C04B2235/6022

  Injection moulding · CPC title

• C04B2235/9638

  Tolerance; Dimensional accuracy · CPC title