Method for manufacturing heated molding material and device for heating molding material

Patent metadata

Field	Value
Publication number	US-11007674-B2
Application number	US-201616065456-A
Country	US
Kind code	B2
Filing date	Dec 13, 2016
Priority date	Dec 25, 2015
Publication date	May 18, 2021
Grant date	May 18, 2021

Abstract

The present invention provides a heating device and a method for manufacturing a heated molding material. The method uses the heating device to continuously manufacture the heated molding material. The heating device includes a heating chamber for heating a molding material, at least one opening section for feeding or expelling molding material therethrough, and a means for using nitrogen gas or superheated steam to expel oxygen gas present in the heating chamber.

First claim

The invention claimed is:

1. A method for producing a shaped product, the method comprising:
heating a molding material in a heating chamber of a heating device; and
arranging a heated molding material in a mold controlled to be at a softening temperature or less; and
compression molding the molding material in the mold,
wherein the heating device comprises:
the heating chamber for heating a molding material; and
at least one opening section for supplying or discharging a molding material therethrough, wherein the opening section is openable and closable and the opening time is 1 second or more and 10 seconds or less per one opening thereof; and
wherein the method further comprises expelling an oxygen gas existing in the heating chamber using a nitrogen gas or a superheated steam.

2. The method for producing the shaped product according to claim 1 , wherein the heated molding material is a molding material for compression molding that contains carbon fibers having a fiber length of 1 to 100 mm and a thermoplastic resin.

3. The method for producing the shaped product according to claim 1 , further comprising:
circulating and heating a gas in the heating chamber; and
jetting a gas containing at least one of a nitrogen gas, a superheated steam or a saturated water vapor in the same direction as a circulating direction of the gas in the heating chamber.

4. The method for producing the shaped product according to claim 1 , further comprising: expelling the oxygen gas existing in the heating chamber using a superheated steam; and introducing a saturated water vapor into the heating device under a pressure higher than the atmospheric pressure.

5. The method for producing the shaped product according to claim 1 , wherein the oxygen gas concentration in the heating chamber is 10 vol% or less.

6. The method for producing the shaped product according to claim 1 , wherein:
the molding material contains carbon fibers and a thermoplastic resin, and is compression-molded into a shaped product after heated, and wherein:
the relationship between the number-average molecular weight Mn1 and the weight-average molecular weight Mw 1 of the thermoplastic resin existing in the surface layer region of the resultant shaped product, and
the number-average molecular weight Mn2 and the weight-average molecular weight Mw2 of the thermoplastic resin existing in the central region of the shaped product satisfy the following relation:
1.0<( Mw 1/ Mn 1)/( Mw 2/ Mn 2)<2.6,

wherein the surface layer region is a region within less than 50 μm from the surface of the shaped product, and the central region is a region other than the surface layer region of the shaped product.

7. The method for producing the shaped product according to claim 1 , wherein:
the temperature of the heated molding material is a temperature higher than the melting point of a crystalline resin by 30° C. or more when the thermoplastic resin in the heated molding material is the crystalline resin, or a temperature higher than the glass transition temperature of an amorphous resin by 100° C. or more when the resin is the amorphous resin.

8. The method for producing the shaped product according to claim 1 , wherein the thickness of the molding material before heating is 0.5 mm or more.

Assignees

• Teijin Ltd

Inventors

• SHINFUKU Yohei
• Amano Noriyuki
• Hua Guofei

Classifications

• B29C35/045 Primary

  using gas or flames · CPC title

• B29C2035/048

  inert gas · CPC title

• B29C35/06

  for articles of indefinite length · CPC title

• B29C35/049

  using steam or damp · CPC title

• B29B13/02

  by heating (B29B13/06, B29B13/08 take precedence) · CPC title