THERMOPLASTIC RESIN COMPOSITION

A thermoplastic resin composition that contains a thermoplastic resin and up to about 30 parts by weight of appearance modifying additives dispersed in the resin, wherein the additives include at least 0.05 parts by weight of metallic particles having an average particle size of from 0.05 to 5 millimeters, at least 0.05 parts by weight of a fiber having an average diameter of from 0.1 to 10 millimeters and an average aspect ratio of from 1:2 to 1:10 and at least 0.05 parts by weight of a mineral particle having an average particle size of from 0.1 and 5 millimeters imparts the appearance of natural stone to articles molded therefrom.

EXAMPLES A composition of the present invention was made by combining the following components in the relative amounts (in pbw) set forth below, in 1 TABLE I SAN: Styrene-acrylonitrile copolymer comprising 72 wt % styrene and 28 wt % acrylonitrile; ABS: Acrylonitrile-butadiene-styrene resin comprising 52 wt % butadiene rubber particles having an average particle size of about 300 nm and a styrene-acrylonitrile-copolymer (36 wt % styrene and 12 wt % acrylonitrile, based on 100 pbw of the acrylonitrile-butadiene-styrene resin) grafted to the butadiene particles; DHT-4A Hydrotalcite additive (DHT-4A, Kyowa); ANTISTAT Antistatic agent (Atmer 163, ICI); WAX1 EBS wax (Uniwax1760 EBS, Unichema); WAX2 Polyethylene wax (Cirea 316A, Allied Corp.); OIL Silicone oil (GE Silicones); RDP Resorcinol diphosphate (Reofos RDP, FMC Corp., Ltd) FIBER1 Black cellulose fiber having nominal diameter of 1 mm and nominal length of 4 (Garal, Towa Japan); FIBER2 White cellulose fiber having nominal diameter of 1 mm and nominal length of 4 mm (Garal white, Towa Japan); FLAKE Metal flake having nominal particle size of 200 microns (Silchroma BG 15, Silberline Ltd); PIGMENT1 Metallic particles having nominal particle size of 65 microns (Silver 1E 004X004, Silberline Ltd); PIGMENT2 Black pigment (Black 7, Cabot Corporation); PIGMENT3 Yellow pigment (Mapicotan 10A, Columbian Carbon); PIGMENT4 Red pigment (Bayferrox 180MPL, Bayer AG); and TiO 2 Titanium dioxide (Tioxide, Europe SA). 2 TABLE I SAN 74 ABS 26 FIBER-1 1.0 FIBER-2 2.5 FLAKE 3.0 PIGMENT-1 0.8 PIGMENT-2 0.0064 PIGMENT-3 0.0044 PIGMENT-4 0.0120 TiO 2 0.32 WAX-1 1.0 WAX-2 0.5 OIL 0.7 DHT-4A 5.0 RDP 7.0 ANTISTAT 0.8 All materials other than the FIBER-1, FIBER-2, FLAKE and PIGMENT-1 were be fed into a Banbury- type mixer and well mixed. The FIBER-1, FIBER-2, FLAKE and PIGMENT-1 were then fed into the mixer and the contents of the mixer were mixed for an other 30 to 40 seconds. After this mixing, the contents of the mixer were fed to a mill (two roll), mixed for about 3 min. and then chopped into pellets in a dicer. The pellets were injection molded to form sample plaques. The plaques had an appearance that was judged to be very similar to natural stone. The sample plaques were free of flow lines, because of the special selected materials used as fillers.