초록 ▼

A process for removing paint from a plastic substrate that typically includes immersing and optionally agitating the painted plastic substrate in a first chemical fluid, removing the substrate from the first chemical fluid, typically immersing and optionally agitating the substrate in a second chemi

A process for removing paint from a plastic substrate that typically includes immersing and optionally agitating the painted plastic substrate in a first chemical fluid, removing the substrate from the first chemical fluid, typically immersing and optionally agitating the substrate in a second chemical fluid, removing the substrate from the second chemical fluid, optionally immersing and optionally agitating the substrate in a third chemical fluid, where the third chemical fluid typically includes substantially the same chemicals as the second chemical fluid, rinsing the substrate, and drying the substrate. The present invention also includes a method for recycling an initially painted plastic substrate.

대표청구항 ▼

The invention claimed is: 1. A process for removing paint from a plastic substrate comprising the steps of: providing a plastic substrate having paint thereon, wherein the plastic substrate comprises a plastic substrate selected from the group consisting of nylon, polypropylene, polyphenylene oxide

The invention claimed is: 1. A process for removing paint from a plastic substrate comprising the steps of: providing a plastic substrate having paint thereon, wherein the plastic substrate comprises a plastic substrate selected from the group consisting of nylon, polypropylene, polyphenylene oxide (PPO), polyethylene, polycarbonate, thermoplastic polyolefins, polyamide (PA), polyphenylene ether (PPE), thermoplastic urethanes, blended nylon, polyvinyl chloride, polystyrenes, and mixtures thereof; immersing the plastic substrate into a first aqueous fluid mix comprising: at least one aromatic alcohol; an alpha-hydroxy acid; an anionic surfactant; 2-mercaptobenzothiazole or salts thereof; xylene; and water; and removing the paint from the plastic substrate using the immersing step. 2. The process of claim 1 further comprising the step of rinsing the plastic substrate, and wherein the process of removing the paint from the plastic substrate generates solid and liquid waste and further comprising the steps of neutralizing the solid waste and neutralizing the liquid waste. 3. The process of claim 1 further comprising the step of reducing the size of the plastic substrate to form a plurality of plastic substrates. 4. The process of claim 1, wherein the paint on the plastic substrate having paint thereon comprises a paint chosen from the group consisting of urethane paints, soft touch paints, enamel based paints, and water-based paints. 5. The process of claim 2, wherein the plastic substrate is rinsed in water and the water collected after the rinsing is the liquid waste and wherein the liquid waste is neutralized with a base such that, after treatment with the base, the liquid waste has undetectable concentrations of acetone, bromobenzene, benzene, bromodichloromethane, bromoform, bromomethane, 2-butanone, carbon tetrachloride, chlorobenzene, chlorodibromomethane, chloroethane, chloroform, chloromethane, 2-chlorotoluene, 4-chlorotoluene, cis-1,2 dichloroethene, trans-1,2-dichloroethene, dibromomethane, 1,2-dibromo-3-chloropropane, 1,2-dichlorobenzene, 1,3-dichlorobenzene, 1,4-dichlorobenzene, 1,1-dichloroethane, 1,2-dichloroethane, 1,1-dichloroethene, 1,2-dichloropropane, 1,3-dichloropropane, 2,2-dichloropropane, 1,1-dichloropropene, cis-1,3-dichloropropene, trans-1,3-dichloropropene, ethylbenzene, ethylenedibromide, fluorotrichloromethane, 2-hexanone, hexachlorobutadiene, isopropylbenzene, 4-methyl-2-pentanone, methylene chloride, methyl-t-butylether, n-butylbenzene, n-propylbenzene, naphthalene, m-xylene, p-xylene, p-isopropyltoluene, o-xylene, sec-butylbenzene, styrene, tert-butylbenzene, tetrachloroethene, 1,1,1,2-tetrachloroethane, 1,1,2,2-tetrachloroethane, toluene, 1,2,3-trichlorobenzene, 1,2,4-trichlorobenzene, 1,1,1-trichloroethane, 1,1,2-trichloroethane, trichlorethane, 1,2,3-trichloropropane, 1,2,4-trimethylbenzene, 1,3,5-trimethylbenzene, and vinyl chloride and wherein the plastic substrate is agitated while immersed in the first aqueous fluid mix. 6. The process of claim 2, wherein the plastic substrate is agitated while immersed in the first aqueous fluid mix. 7. The process of claim 2, wherein the paint on the plastic substrate having paint thereon comprises a paint chosen from the group consisting of urethane paints, soft touch paints, enamel based paints, and water-based paints. 8. The process of claim 2, wherein the plastic substrate is rinsed in water and the water collected after the rinsing is the liquid waste and further comprising the steps of evaporating the water from the liquid waste and safely disposing of the liquid and the solid waste. 9. The process of claim 3, wherein the plastic substrate is partially coated with paint and wherein the step of reducing the size of the plastic substrate to form a plurality of plastic substrates is before the step of immersing the partially coated substrate into the first aqueous fluid mix. 10. The process of claim 6, wherein the plastic substrate is rinsed with water after being immersed in the first aqueous fluid mix and the immersion and rinsing steps remove the paint from the plastic substrate. 11. The process of claim 10 further comprising the step of safely disposing of the liquid and the solid waste. 12. The process of claim 10, wherein the paint on the plastic substrate having paint thereon comprises a paint chosen from the group consisting of urethane paints, soft touch paints, enamel based paints, and water-based paints. 13. The process of claim 12, wherein the first aqueous fluid mix consists essentially of the at least one aromatic alcohol; the alpha-hydroxy acid; the anionic surfactant; the 2-mercaptobenzothiazole or salts thereof; the xylene; and water. 14. The process of claim 12, wherein the at least one aromatic alcohol comprises benzyl alcohol and the at least one aromatic alcohol comprises from about 50% to about 55% by weight of the first aqueous fluid mix; wherein the anionic surfactant comprises sodium lauryl sulphate and the anionic surfactant comprises from about 0.5% to 1.5% by weight of the first aqueous fluid mix; wherein 2-mercaptobenzothiazole or salts thereof comprises from about 0.5% to about 1% by weight of the first aqueous fluid mix; wherein the water comprises from about 30% to about 40% by weight of the first aqueous fluid mix; wherein the xylene comprises from about 0.1% to about 1% by weight of the first aqueous fluid mix; and wherein the alpha-hydroxy acid comprises glycolic acid and the alpha-hydroxy acid comprises from about 5% to about 10% by weight of the first aqueous fluid mix; and wherein the first aqueous fluid mix comprises a temperature of about 140�� F. to about 180�� F. 15. The process of claim 14 further comprising the step of reducing the size of the plastic substrate to form a plurality of plastic substrates. 16. The process of claim 15, wherein the plastic substrate is partially coated with paint and wherein the step of reducing the size of the plastic substrate to form a plurality of plastic substrates is before the step of immersing the partially coated substrate into the first aqueous fluid mix. 17. The process of claim 16 further comprising the step of immersing the partially coated plastic substrate into a second fluid mix comprising dipropylene glycol dimethyl ether, dimethyl succinate, dimethyl glutarate, and dimethyl adipate and wherein the second fluid mix comprises: from about 15% to about 25% dipropylene glycol dimethyl ether by weight of the second fluid mix; from about 55% to about 65% dimethyl succinate by weight of the second fluid mix; from about 1% to about 2% dimethyl glutarate by weight of the second fluid mix; and from about 15% to about 25% dimethyl adipate by weight of the second fluid mix. 18. The process of claim 17 further comprising the step of immersing the partially coated plastic substrate into a third fluid mix after immersing the partially coated plastic substrate in the second fluid mix, wherein the third fluid mix comprises dipropylene glycol dimethyl ether, dimethyl succinate, dimethyl glutarate, and dimethyl adipate and wherein the third fluid mix comprises: from about 15% to about 25% dipropylene glycol dimethyl ether by weight of the second fluid mix; from about 55% to about 65% dimethyl succinate by weight of the second fluid mix; from about 1% to about 2% dimethyl glutarate by weight of the second fluid mix; and from about 15% to about 25% dimethyl adipate by weight of the second fluid mix; and wherein the second fluid mix is diluted with water and the third fluid mix is diluted with water; and wherein the second fluid mix has a viscosity of 5-10 cps at 100% prior to dilution in water, Brookfield Spindle #3, 60 rpm 78�� F.