Claims
- 1. A process for reclaiming the residuals from the manufacture of high pressure laminates (HPLs), said process comprising the steps of:
- (i) providing a feed material comprising scraps from the manufacture of HPLs, said feed material comprising at least 50% by weight of cellulose partially impregnated with completely polycondensed thermosetting resin(s) and at least 20% by weight of partially polycondensed thermosetting resin(s);
- (ii) grinding the feed material and producing a powder comprising particles having a predetermined size and a lower degree of moisture relative to the feed material prepared in step (i) if moisture exists in the feed material;
- (iii) preparing a melted mass of thermoplastic material;
- (iv) mixing the ground feed material from step (ii) with the melted mass from step (iii), while maintaining the powder at a temperature ranging from 130.degree. to 260.degree. C. and pressure ranging from 60 to 90 kg/cm.sup.2 thereby further polycondensing the partially polycondensed thermosetting resin(s) of the feed material;
- (v) degassing the mixed mass from step (iv) to release formaldehyde and the other volatile products generated during the further polycondensation of the partially polycondensed thermosetting resin(s); and
- (vi) forming semi-finished articles form the degassed mass and cooling said semi-finished articles.
- 2. A process according to claim 1, wherein the feed material comprises scraps produced during trimming of the contours of an impregnated paper stack protruding from press plates during HPL manufacture, scraps produced from cutouts of the paper from various impregnation steps, powders and chips produced during grinding or milling of the high pressure laminate back side.
- 3. A process according to claim 1, wherein in step (ii) a fine powder is produced comprising particles having particle sizes or diameters smaller than 4 mm.
- 4. A process according to claim 1, wherein said thermoplastic material is present in the mixture in an amount of from 30 to 60% by weight.
- 5. A process according to claim 1, wherein the thermoplastic material is selected from the group consisting of polyethylene resins, polypropylene resins, polyvinyl chloride resins, acrylonitrile-butadiene-styrene resins, acetal resins, and mixtures thereof.
- 6. A process according to claim 1, wherein a mixture between the powder of ground feed material and the mass of thermoplastic material is obtained by contemporary heating, pressing and mixing the components for a time sufficient to allow further polycondensation of the partially polycondensed thermosetting resin(s) present in the ground feed material.
Priority Claims (1)
Number |
Date |
Country |
Kind |
67284 A/89 |
Apr 1989 |
ITX |
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RELATED APPLICATIONS
This application is a continuation-in-part application of U.S. patent application Ser. No. 07/498,648 filed on Mar. 26, 1990, entitled "A Process For Manufacturing a Composite Material Comprising Thermoplastic Polymers and Residuals From the Manufacture of Plastic Laminates, and the Composite Material So Obtained", now abandoned.
US Referenced Citations (11)
Foreign Referenced Citations (2)
Number |
Date |
Country |
57-140122 |
Aug 1982 |
JPX |
60-234830 |
Nov 1985 |
JPX |
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
498648 |
Mar 1990 |
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