Claims
- 1. A process for reducing residual stress in a resin molded article, which consists essentially of heating an injection-molded article of a thermoplastic resin by means of a combination of far infrared radiation with far infrared rays having a frequency of from 10.sup.11 to 10.sup.14 Hz and hot-air flow, thereby to diminish residual stress in the molded article in a short period of time, wherein the heating is conducted at a temperature 10.degree. to 50.degree. C. lower than the low-load heat distortion temperature of the thermoplastic resin.
- 2. A process as claimed in claim 1, wherein the heating of the molded article by means of a combination of far infrared radiation and hot-air flow is conducted immediately after molding.
- 3. A process as claimed in claim 1, wherein the molded article is an article for use as an automotive lamp lens.
- 4. A process as claimed in claim 1, wherein the thermoplastic resin is a polycarbonate resin.
- 5. A process as claimed in claim 4, wherein the heating is conducted at a temperature of 120.degree. to 135.degree. C.
Priority Claims (1)
Number |
Date |
Country |
Kind |
2-88179 |
Apr 1990 |
JPX |
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CROSS REFERENCE TO THE RELATED APPLICATION
This application is a continuation-in-part application of U.S. patent application Ser. No. 07/679,851, filed Apr. 3, 1991, entitled "PROCESS FOR PRODUCING RESIN MOLDED ARTICLE HAVING DIMINISHED RESIDUAL STRESS", now abandoned.
US Referenced Citations (6)
Foreign Referenced Citations (4)
Number |
Date |
Country |
693109 |
Aug 1964 |
CAX |
0145864 |
Jun 1985 |
EPX |
2038794 |
Feb 1971 |
DEX |
1629508 |
Aug 1971 |
DEX |
Non-Patent Literature Citations (1)
Entry |
Patent Abstracts of Japan, abstract of JP-A 61-032 419 Mitsubishi Electric Corp. |
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
679851 |
Apr 1991 |
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