US4629650A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for producing molded thermoplastic resin
Assignee: Asahi Kasei Corp
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Filing: 1983-12-27
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Granted: 1986-12-16
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Expires: 2003-12-27
Abstract
Abstract This invention concerns a process for producing a molded thermoplastic resin by interposing during molding a thermoplastic resin different from the thermoplastic resin to be molded as a skin layer between the die surface and the thermoplastic resin to be molded. A lubricant is provided to lubricate the interface between the die surface and the skin layer. After molding, the skin layer with lubricant is removed.
Inventors
- 👤 Hiroshi Kataoka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 13:29
CPC Classifications
B; B29; B29C; B29C43/00; B29C43/02; B29C43/20; B29C43/203; B29C44/00; B29C44/34; B29C44/36; B29C44/46; B29C44/50; B29C44/505; B29C44/507; B29C48/00; B29C48/03; B29C48/07; B29C48/08; B29C48/09; B29C48/16; B29C48/18; B29C48/21; B29C48/25; B29C48/30; B29C48/305; B29C48/307; B29C48/32; B29C48/335; B29C48/336; B29C48/337; B29C48/94; B29C55/00; B29L; B29L2009/00; Y; Y10; Y10T; Y10T156/00; Y10T156/11; Y10T156/1168; Y10T428/00; Y10T428/24; Y10T428/24942; Y10T428/2495
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
164 words
A process for compression molding a thermoplastic resin comprising the steps of: (a) providing at least one removably thermoplastic resin skin between a thermoplastic core resin to be molded and the surface of a mold or die; (b) dispersing a lubricant between said removable skin or skins and said mold or die; and (c) molding said thermoplastic core resin in the presence of said removalbe skin or skins and said lubricant by compression molding at a temperature equal to or greater than the glass transition temperature of said thermoplastic core resin such that the following conditions are met: (i) said removable skin or skins have a flowability greater than the flowability of said thermoplastic core resin; (ii) said removable skin or skins are about 1/10 or less as thick as said thermoplastic core resin; and (iii) sufficient force is applied to said removable skin or skins and said thermplastic core resin during molding to achieve substantially uniform plug flow in said thermoplastic core resin.
Claim 2
Dependent Claim
164 words
A process for compression molding a thermoplastic resin comprising the steps of: (a) providing at least one removably thermoplastic resin skin between a thermoplastic core resin to be molded and the surface of a mold or die; (b) dispersing a lubricant between said removable skin or skins and said mold or die; and (c) molding said thermoplastic core resin in the presence of said removalbe skin or skins and said lubricant by compression molding at a temperature equal to or greater than the glass transition temperature of said thermoplastic core resin such that the following conditions are met: (i) said removable skin or skins have a flowability greater than the flowability of said thermoplastic core resin; (ii) said removable skin or skins are about 1/10 or less as thick as said thermoplastic core resin; and (iii) sufficient force is applied to said removable skin or skins and said thermplastic core resin during molding to achieve substantially uniform plug flow in said thermoplastic core resin.
Claim 3
Dependent Claim
16 words
The process according to claim 1, wherein said core resin is made of an acrylic resin.
Claim 4
Dependent Claim
29 words
The process according to claim 1, wherein said core resin is made of a ultra-high molecular weight thermoplastic resin having a viscosity average molecular weight of 800,000 or more.
Claim 5
Dependent Claim
14 words
The process according to claim 1, wherein said core resin has a three-layer structure.
Claim 6
Dependent Claim
30 words
The process according to claim 1 wherein said removable skin or skins is or are of at least one resin selected from the group consisting of polyolefin and polyamide resins.
Claim 7
Dependent Claim
23 words
The process according to claim 1, wherein said removable skin or skins has a thickness of from about 0.01 to about 2 mm.
Claim 8
Dependent Claim
28 words
The process according to claim 1, wherein said removable skin or skins has or have a double-layer structure including an outer skin layer and an inner skin layer.
Claim 9
Dependent Claim
57 words
The process according to claim 7, wherein the viscosity of the thermoplastic resin used for said outer skin layer is lower than the viscosity of said thermoplastic core resin, and the viscosity of the thermoplastic resin used for said inner skin layer is greater than the viscosity of the thermoplastic resin used for said outer skin layer.
Claim 10
Dependent Claim
34 words
The process according to claim 1 wherein the step of dispersing a lubricant between said removable skin or skins and said mold or die comprises lubricating the mold or die surface with a lubricant.
Claim 11
Dependent Claim
37 words
The process according to claim 1 wherein the step of dispersing a lubricant between said removable skin or skins and said mold or die comprises coating the surface of said removable skin or skins with a lubricant.
Claim 12
Dependent Claim
48 words
The process according to claim 1 wherein the step of dispersing a lubricant between said removable skin or skins and said mold or die comprises incorporating said lubricant into said removable skin or skins and allowing said removable skin or skins to bleed out said lubricant during molding.
Claim 13
Dependent Claim
77 words
The process according to claim 1, wherein said molding step comprises heating said core resin and removably skin or skins to a temperature higher than the glass transition temperature and lower than the melting point of the thermoplastic core resin compressing said core resin and removable skin or skins in the die heated to approximately the same temperature to form a biaxially oriented sheet having a thickness of from about 1 to about 10 mm after cooling.
Claim 14
Dependent Claim
27 words
A process according to claim 12, wherein the step of removing the removable skin or skins from the biaxially oriented sheet occurs after the articles is molded.
Claim 15
Dependent Claim
10 words
A molded article made by the process of claim 1.
Claim 16
Dependent Claim
16 words
A molded article of an ultra-high molecular weight resin made by the process of claim 1.
Claim 17
Dependent Claim
15 words
A molded article formed from the process of claim 1 wherein said article is oriented.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-12-15 | 1990-06-16 | 1990-12-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-12-15 | 1994-06-16 | 1994-12-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-12-15 | 1998-06-16 | 1998-12-16 | $7700.00 | Window Closed / Lapsed |