Method for manufacturing resin molded products

Abstract

Provided is a resin composition that can yield a resin molded article that exhibits an excellent heat dissipation behavior.　The resin composition comprises a thermoplastic resin, graphite, and a fibrous body. This a resin composition for which: when a resin molded article 1 with a length of 100 mm x width of 100 mm x thickness of 2 mm is obtained by carrying out molding by filling the molten resin composition into a mold from the direction orthogonal to the thickness direction of the resulting molded article 1, and when a cross section of the resin molded article 1 is taken by sectioning along the thickness direction Z and the direction X that is parallel to the filling direction and this cross section is divided into 5 equal regions 1A-1E in the thickness direction Z, the average angle of orientation (A) with respect to the surface direction of the graphite in at least one of the surfacemost layer regions 1A and 1E is not more than 15° and the average angle of orientation (B) with respect to the surface direction of the graphite in the middle region 1C is at least 35°.

Claims

1. A method for manufacturing a resin molded article, which is a molded article of a resin composition comprising a thermoplastic resin, graphite, and a fibrous material, A step of preparing a resin composition, which is a mixture obtained by mixing resin composition (A) and resin composition (B), A step of injection molding by filling a mold with the molten resin composition from a direction perpendicular to the thickness direction of the resulting resin molded body, Equipped with, The resin composition (A) is a compound obtained by melt-kneading 10% to 70% by weight of thermoplastic resin (a) and 30% to 90% by weight of graphite. The resin composition (B) contains 10% to 70% by weight of a thermoplastic resin (b) and 30% to 90% by weight of fibers with a length of 1 mm or more, and the resin composition (B) is a compound obtained by impregnating the molten thermoplastic resin (b) with the fibers. When the aforementioned resin molded body measuring 100 mm in length, 100 mm in width, and 2 mm in thickness is obtained, A method for manufacturing a resin molded article, wherein, in a cross-section obtained by cutting the resin molded article in a direction parallel to the filling direction and in the thickness direction, the average orientation angle (A) of the graphite with respect to the surface direction in at least one of the outermost layers of the region divided into five equal parts in the thickness direction is 15° or less, and the average orientation angle (B) of the graphite with respect to the surface direction in the central region is 35° or more.

2. A method for manufacturing a resin molded article, which is a molded article of a resin composition comprising a thermoplastic resin, graphite, and a fibrous material, A step of preparing a resin composition, which is a mixture obtained by mixing resin composition (A) and resin composition (B), A step of injection molding by filling a mold with the molten resin composition from a direction perpendicular to the thickness direction of the resulting resin molded body, Equipped with, The resin composition (A) is a compound obtained by melt-kneading 10% to 70% by weight of thermoplastic resin (a) and 30% to 90% by weight of graphite. The resin composition (B) contains 10% to 70% by weight of a thermoplastic resin (b) and 30% to 90% by weight of fibers with a length of 1 mm or more, and the resin composition (B) is a compound obtained by impregnating the molten thermoplastic resin (b) with the fibers. When the aforementioned resin molded body measuring 100 mm in length, 100 mm in width, and 2 mm in thickness is obtained, A method for manufacturing a resin molded article, wherein, in a cross-section obtained by cutting the resin molded article in a direction perpendicular to the filling direction and in the thickness direction, the average orientation angle (A) of the graphite with respect to the surface direction in at least one of the outermost layers of the region divided into five equal parts in the thickness direction is 10° or less, and the average orientation angle (B) of the graphite with respect to the surface direction in the central region is 15° or more.

3. A method for manufacturing a resin molded article, which is a molded article of a resin composition comprising a thermoplastic resin, graphite, and a fibrous material, A step of preparing a resin composition, which is a mixture obtained by mixing resin composition (A) and resin composition (B), A step of injection molding by filling a mold with the molten resin composition from a direction perpendicular to the thickness direction of the resulting resin molded body, Equipped with, The resin composition (A) is a compound obtained by melt-kneading 10% to 70% by weight of thermoplastic resin (a) and 30% to 90% by weight of graphite. The resin composition (B) contains 10% to 70% by weight of a thermoplastic resin (b) and 30% to 90% by weight of fibers with a length of 1 mm or more, and the resin composition (B) is a compound obtained by impregnating the molten thermoplastic resin (b) with the fibers. When the aforementioned resin molded body measuring 100 mm in length, 100 mm in width, and 2 mm in thickness is obtained, A method for manufacturing a resin molded article, wherein, in a cross-section obtained by cutting the resin molded article in a direction parallel to the filling direction and in the thickness direction, the ratio (average orientation angle (B) / average orientation angle (A)) of the average orientation angle of the graphite with respect to the surface direction in the central region of the five equally divided regions in the thickness direction to the average orientation angle of the graphite with respect to the surface direction in at least one of the outermost layers (A) is 3.5 or more.

4. A method for manufacturing a resin molded article, which is a molded article of a resin composition comprising a thermoplastic resin, graphite, and a fibrous material, A step of preparing a resin composition, which is a mixture obtained by mixing resin composition (A) and resin composition (B), A step of injection molding by filling a mold with the molten resin composition from a direction perpendicular to the thickness direction of the resulting resin molded body, Equipped with, The resin composition (A) is a compound obtained by melt-kneading 10% to 70% by weight of thermoplastic resin (a) and 30% to 90% by weight of graphite. The resin composition (B) contains 10% to 70% by weight of a thermoplastic resin (b) and 30% to 90% by weight of fibers with a length of 1 mm or more, and the resin composition (B) is a compound obtained by impregnating the molten thermoplastic resin (b) with the fibers. When the aforementioned resin molded body measuring 100 mm in length, 100 mm in width, and 2 mm in thickness is obtained, A method for manufacturing a resin molded article, wherein, in a cross-section obtained by cutting the resin molded article in a direction perpendicular to the filling direction and in the thickness direction, the ratio (average orientation angle (B) / average orientation angle (A)) of the average orientation angle of the graphite with respect to the surface direction in the central region of the five equally divided regions in the thickness direction to the average orientation angle of the graphite with respect to the surface direction in at least one of the outermost regions is 2 or more.

5. A method for manufacturing a resin molded article, which is a molded article of a resin composition comprising a thermoplastic resin, graphite, and a fibrous material, A step of preparing a resin composition, which is a mixture obtained by mixing resin composition (A) and resin composition (B), A step of injection molding by filling a mold with the molten resin composition from a direction perpendicular to the thickness direction of the resulting resin molded body, Equipped with, The resin composition (A) is a compound obtained by melt-kneading 10% to 70% by weight of thermoplastic resin (a) and 30% to 90% by weight of graphite. The resin composition (B) contains 10% to 70% by weight of a thermoplastic resin (b) and 30% to 90% by weight of fibers with a length of 1 mm or more, and the resin composition (B) is a compound obtained by impregnating the molten thermoplastic resin (b) with the fibers. When the aforementioned resin molded body measuring 100 mm in length, 100 mm in width, and 2 mm in thickness is obtained, A method for manufacturing a resin molded article, wherein M is the peak intensity ratio (D / G ratio) of the D band and the G band obtained when the surface layer of the resin molded article is subjected to Raman spectroscopy, and N is the peak intensity ratio (D / G ratio) of the D band and the G band obtained when the central part of the cross-section obtained when the resin molded article is cut along the thickness direction is subjected to Raman spectroscopy, and the ratio M / N is 0.30 or more.

6. The method for manufacturing a resin molded article according to any one of claims 1 to 5, wherein the graphite is plate-shaped graphite.

7. The method for manufacturing a resin molded article according to any one of claims 1 to 6, wherein the fibrous material is at least one selected from the group consisting of glass fibers, carbon fibers, and resin fibers.

8. A method for producing a resin molded article according to any one of claims 1 to 7, further comprising carbon black.

9. A method for producing a resin molded article according to any one of claims 1 to 8, wherein the thermoplastic resin includes an olefin-based resin.

10. When a resin molded body measuring 100 mm in length, 100 mm in width, and 2 mm in thickness is obtained, A method for manufacturing a resin molded article according to any one of claims 1 to 9, wherein the in-plane thermal conductivity of the main surface of the resin molded article is 2 W / (m·K) or more.

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