Fiber-reinforced resin molding material molded product and method of producing same

Patent metadata

Field	Value
Publication number	US-11794419-B2
Application number	US-202017598504-A
Country	US
Kind code	B2
Filing date	Mar 9, 2020
Priority date	Mar 27, 2019
Publication date	Oct 24, 2023
Grant date	Oct 24, 2023

Abstract

A fiber-reinforced resin molding material molded product includes a fiber-reinforced resin molding material prepared by impregnating chopped fiber bundles obtained by cutting a reinforcing fiber bundle with a matrix resin, wherein in a region excluding 30 mm from an edge of the molded product, when an arbitrary rectangular region having an area of 40 mm2 or more and defined by a thickness of the molded product and a width in a direction perpendicular to a thickness direction of the molded product is set in a cross section in an arbitrary thickness direction of the molded product, with respect to a bundle thickness of the chopped fiber bundles present in the set rectangular region.

First claim

The invention claimed is:

1. A fiber-reinforced resin molding material molded product which is a molded product [D] comprising a fiber-reinforced resin molding material [C] prepared by impregnating chopped fiber bundles [A] obtained by cutting a reinforcing fiber bundle with a matrix resin [B], wherein in a region excluding 30 mm from an edge of the molded product [D], when an arbitrary rectangular region having an area of 40 mm 2 or more and defined by a thickness of the molded product and a width in a direction perpendicular to a thickness direction of the molded product is set in a cross section in an arbitrary thickness direction of the molded product [D], with respect to a bundle thickness [E] of the chopped fiber bundles [A] present in the set rectangular region, requirements [1]-[3] are satisfied:
[1] when a frequency distribution in which values of the bundle thickness [E] are distributed in sections set from 0 μm at intervals of every 10 μm is created, the most frequent value of the bundle thickness [E] in a section representing the highest value is 30-100 μm;
[2] a ratio of a number of the chopped fiber bundles [A] having a bundle thickness [E] of 200 μm or more to a total number of the chopped fiber bundles [A] is 5% or less; and
[3] a CV value of the bundle thickness [E] is in a range of 10-60%.

2. The molded product according to claim 1 , wherein the ratio of a number of the chopped fiber bundles [A] having a bundle thickness [E] of 200 μm or more to a total number of the chopped fiber bundles [A] is 0.1-5%.

3. The molded product according to claim 1 , wherein an average value of the bundle thickness [E] is 50 μm or more and 100 μm or less.

4. The molded product according to claim 1 , wherein the reinforcing fiber bundle is a carbon fiber bundle.

5. The molded product according to claim 1 , wherein the matrix resin [B] is a thermosetting resin selected from a vinyl ester resin, an epoxy resin or an unsaturated polyester resin.

6. A method of producing a fiber-reinforced resin molding material molded product which is a molded product [D] comprising a fiber-reinforced resin molding material [C] is prepared by impregnating chopped fiber bundles [A] obtained by cutting a reinforcing fiber bundle with a matrix resin [B], wherein in a region excluding 30 mm from an edge of the molded product [D], when an arbitrary rectangular region having an area of 40 mm 2 or more and defined by a thickness of the molded product and a width in a direction perpendicular to a thickness direction of the molded product is set in a cross section in an arbitrary thickness direction of the molded product [D], with respect to a bundle thickness [E] of the chopped fiber bundles [A] present in the set rectangular region, requirements [1]-[3] are satisfied:
[1] when a frequency distribution in which values of the bundle thickness [E] are distributed in sections set from 0 μm at intervals of every 10 μm is created, the most frequent value of the bundle thickness [E] in a section representing the highest value is 30-100 μm;
[2] a ratio of a number of the chopped fiber bundles [A] having a bundle thickness [E] of 200 μm or more to a total number of the chopped fiber bundles [A] is 5% or less; and
[3] a CV value of the bundle thickness [E] is 10-60%.

7. The method according to claim 6 , wherein the ratio of a number of the chopped fiber bundles [A] having a bundle thickness [E] of 200 μm or more to a total number of the chopped fiber bundles [A] is 0.1-5%.

8. The method according to claim 6 , wherein the chopped fiber bundles [A] are distributed by a distributor [G] after widening and cutting the reinforcing fiber bundle.

9. The method according to claim 8 , wherein the distributor [G] distributes the chopped fiber bundles by hitting them with rods, and the speed of the rods hitting the chopped fiber bundles is 0.1-8 m/sec.

10. The method according to claim 8 , wherein with respect to the widening of the reinforcing fiber bundle, the widening ratio is controlled at 300-1,200%.

11. The method according to claim 6 , wherein the chopped fiber bundles [A] are distributed by a distributor [G] after widening the reinforcing fiber bundle and after cutting a partially separated fiber bundle [F] that has been subjected to partial separation processing for intermittently providing slits along a fiber orientation direction of the widened reinforcing fiber bundle.

Assignees

• Toray Industries

Inventors

• Yamanaka Yusuke
• Hashimoto Takafumi
• Motohashi Tetsuya
• Ono Yasukazu

Classifications

• B29C70/12 Primary

  using fibres of short length, e.g. in the form of a mat {(non-woven fabrics per se D04H1/00)} · CPC title

• B29B15/105

  of reinforcement of definite length with a matrix in solid form, e.g. powder, fibre or sheet form (calendering B29C70/506) · CPC title

• B29C70/42

  for producing articles of definite length, i.e. discrete articles · CPC title

• C08J5/042 Primary

  with carbon fibres · CPC title

• B29K2101/10

  Thermosetting resins · CPC title