Isotropic fiber-reinforced thermoplastic resin sheet, and process for production and molded plate thereof

Patent metadata

Field	Value
Publication number	US-9545760-B2
Application number	US-6319106-A
Country	US
Kind code	B2
Filing date	Aug 14, 2006
Priority date	Aug 18, 2005
Publication date	Jan 17, 2017
Grant date	Jan 17, 2017

Abstract

An isotropic fiber-reinforced thermoplastic resin sheet wherein a chopped strand prepreg comprising a thermoplastic resin and a reinforcing fiber is layered so that the fiber orientation is random, the prepreg having a fiber volume fraction (Vf) of 20% to 50%, a length in the fiber axis direction of 15 to 45 mm, and a thickness of no greater than 0.13 mm, and the layered material is molded into sheet form by heating and pressing, and a molded plate obtained from the isotropic fiber-reinforced thermoplastic resin sheet. Even if the volume fraction of the reinforcing fiber is relatively low, a fiber-reinforced thermoplastic resin sheet and a molded plate that are excellent in terms of mechanical properties and their uniformity can be obtained.

First claim

What is claimed is:

1. A molded plate in which one fiber-reinforced thermoplastic resin sheet or a layered plurality of fiber-reinforced thermoplastic resin sheets are integrally molded, the molded plate comprising:
an isotropic fiber-reinforced thermoplastic resin sheet comprising a layered material molded into sheet form by heating and pressing, the layered material being a chopped strand prepreg, comprising a thermoplastic resin as a matrix and a reinforcing fiber, that is layered so that the fiber orientation is random, the prepreg having a fiber volume fraction of 20% to 50%, a length in the fiber axis direction of 15 to 45 mm, and a thickness of no greater than 0.13 mm, and
the theoretical number of layers of the molded plate satisfying the following expression:
theoretical number of layers=(thickness of molded plate)/(thickness of one prepreg)≧10.

2. The molded plate according to claim 1 , wherein the reinforcing fiber is carbon fiber.

3. The molded plate according to claim 1 , wherein CV values of the molded plate for flexural strength and flexural modulus of elasticity measured in accordance with JIS K 7017 are no greater than 10.

4. The molded plate according to claim 1 , wherein the prepreg has a thickness of 0.05-0.10 mm.

5. The molded plate according to claim 1 , wherein the theoretical number of layers is equal to or greater than 15.

6. The molded plate according to claim 1 , wherein the prepreg has a width of 10 to 30 mm with respect to the longitudinal direction.

Assignees

• Ohki Takeru
• Naito Takeshi
• Umemoto Yoshitaka
• Teijin Ltd

Inventors

• Ohki Takeru
• Naito Takeshi
• Umemoto Yoshitaka

Classifications

• B29K2307/00

  Use of elements other than metals as reinforcement · CPC title

• C08J2377/02

  Polyamides derived from omega-amino carboxylic acids or from lactams thereof (C08J2377/10 takes precedence) · CPC title

• B29K2101/12

  Thermoplastic materials · CPC title

• C08J5/042

  with carbon fibres · CPC title

• B29C43/003

  characterised by the choice of material · CPC title