Claims
- 1. A moldable and pigmentable heat-curable composition for obtaining molded articles having smooth surfaces, a homogeneous distribution of pigments and a zero or practically zero shrinkage or a slight expansion, said composition including, by weight:
- (a) from 15 to 45% of an unsaturated polymer or an epoxy vinyl ester,
- (b) from 0.1 to 1% of a catalyst,
- (c) from 3 to 15% of (meth)acrylic polymer powder particles having a dimension smaller than 150 .mu.m, wherein said (meth)acrylic polymer is a homopolymer of methyl methacrylate or a copolymer of methyl metbacrylate with an alkyl acrylate or vinyl monomer,
- (d) from 3 to 60% of inorganic fillers,
- (e) from 0 to 5% of organic or inorganic pigments, and
- (f) up to 60% of reinforcing fibers.
- 2. A composition in accordance with claim 1, wherein the heat-curable resin is an unsaturated polyester resin prepared from maleic acid, maleic anhydride or fumaric acid and from at least one diol.
- 3. A composition in accordance with claim 2, wherein the polyester is prepared from additional components of an aromatic, cyclo-aliphatic or saturated aliphatic diacid or anhydride thereof.
- 4. A composition in accordance with claim 1, in which the (meth)acrylic polymer is a methyl methacrylate homopolymer or a co-polymer of methyl methacrylate and an alkyl acrylate comonomer in which the alkyl group has from 1 to 4 carbon atoms or a vinyl comonomer.
- 5. A composition in accordance with claim 4, wherein the (meth)acrylic polymer is polymethyl methacrylate having a weight-average molecular mass greater than 100,000.
- 6. A composition in accordance with claim 1, wherein the powder particles have a dimension of between 10 and 50,.mu.m.
- 7. A composition in accordance with claim 1, wherein the catalyst comprises organic peroxide.
- 8. A composition in accordance with claim 1, wherein the inorganic filler is calcium carbonate or alumina hydrate.
- 9. A composition in accordance with claim 1, comprising reinforcing fibers selected from the group consisting of glass, carbon and aramid fibers.
- 10. A composition in accordance with claim 1 comprising from 0.1 to 5% by weight of organic or inorganic pigments.
- 11. A composition in accordance with claim 10, in which the pigment is selected from the group consisting of a conductive pigment and carbon black.
- 12. A composition in accordance with claim 1, further comprising an anti-shrinkage agent selected from the group consisting of polystyrene, polyvinyl acetate, elastomers and copolymers of ethylene and of vinyl acetate.
- 13. A composition in accordance with claim 1, further comprising a mold release agent selected from the group consisting of calcium stearate, zinc stearate and wax.
- 14. A composition in accordance with claim 1, including, by weight:
- from 15 to 35% of a heat-curable resin
- from 0.3 to 0.9% of a catalyst
- from 35 to 56% of an inorganic filler
- from 0.1 to 5% of a pigment
- from 7 to 25% of reinforcing fibers
- from 4 to 12% of (meth)acrylic polymer powder
- from 0 to 12% of an anti-shrinkage agent
- from 0.5 to 4% of a mold release agent.
- 15. A composition in accordance with claim 1, including 0 to 10% by weight of ballotini.
- 16. A composition in accordance with claim 1, further comprising vegetable and/or synthetic fibers.
- 17. A composition in accordance with claim 16, including, by weight:
- from 15 to 35% of a heat-curable resin
- from 0.3 to 0.9% of a catalyst
- from 3 to 20% of an inorganic filler
- from 0.1 to 5% of a pigment
- from 7 to 25% of reinforcing fibers
- from 4 to 12% of (meth)acrylic polymer powder particles
- from 0 to 18% of an anti-shrinkage agent
- from 0.5 to 4% of a mold release agent
- from 5 to 35% of cellulose fibers.
- 18. A molded article having zero or practically zero shrinkage or slight expansion obtained from the composition in accordance with claim 1, and including from 1 to 4% by weight of a conductive pigment, exhibiting a surface resistivity of between 10.sup.3 and 10.sup.7 .OMEGA./log 10.
- 19. A molded article having zero or practically zero shrinkage or slight expansion obtained from the composition in accordance with claim 17, and including from 1 to 4% by weight of a conductive pigment, exhibiting a surface resistivity of between 10.sup.3 and 10.sup.7 .OMEGA./log 10.
- 20. A composition according to claim 1, wherein the heat-curable resin is an unsaturated polyester in liquid form diluted in an ethylenically unsaturated monomer selected from the group consisting of styrene, .alpha.-methystyrene and vinyltoluene; the catalyst is a liquid; and the composition is obtained by blending solid components of the composition; blending liquid components of the composition; and impregnating the blended solid components with the blended liquid components.
- 21. A molded article having zero or practically zero shrinkage or slight expansion obtained from the composition in accordance with claim 20, and including from 1 to 4% by weight of a conductive pigment, exhibiting a surface resistivity of between 10.sup.3 and 10.sup.7 .OMEGA./log 10.
- 22. A molded article according to claim 18, having an electrostatically applied coating uniformly and directly deposited thereon, whereby an intermediate conductive primer coat is not required.
- 23. A molded article according to claim 21, having an electrostatically applied coating uniformly and directly deposited thereon, whereby an intermediate conductive primer coat is not required.
- 24. A composition in accordance with claim 1, wherein the powder comprises particles having a dimension of less than 10 .mu.m.
- 25. A composition in accordance with claim 1, wherein the powder comprises particles having a dimension of less than 1 .mu.m.
- 26. A composition in accordance with claim 1, wherein the powder particles have a dimension of less than 10 .mu.m.
- 27. A composition in accordance with claim 1, wherein the powder particles have a dimension of less than 1 .mu.m.
Priority Claims (1)
Number |
Date |
Country |
Kind |
95 07900 |
Jun 1995 |
FRX |
|
Parent Case Info
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation-in-part application of Ser. No. 081/671,763 abandoned, filed Jun. 28, 1996, which is hereby incorporated by reference.
Foreign Referenced Citations (7)
Number |
Date |
Country |
0 454 517 |
Oct 1991 |
EPX |
2021415 |
Jul 1970 |
FRX |
1 953 062 |
May 1970 |
DEX |
61-57644 |
Mar 1986 |
JPX |
63-69812 |
Mar 1988 |
JPX |
4-209651 |
Dec 1990 |
JPX |
6-25539 |
Feb 1994 |
JPX |
Non-Patent Literature Citations (3)
Entry |
Materiaux, Polymeres Acryliques, pp. 224-231. |
Abreviations. |
Polymerisation en Suspension. |
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
671763 |
Jun 1996 |
|