Water impervious carpet backing

Abstract

Aqueous liquids, such as water, can normally penetrate through conventional carpet. Thus, in cases where water is spilled on conventional carpet, it typically seeps through and ultimately reaches the flooring below. This trapped water can lead to bacterial or fungal growth which can further cause odors and/or deterioration of the carpet backing or flooring. This invention relates to a technique for treating carpet to render it impervious to aqueous liquids. This invention specifically discloses a process for treating carpet which is comprised of a pile and a backing to render said carpet impervious to aqueous liquids, said process comprising the steps of (1) coating the bottom side of said backing with a water-resistant coating composition which is comprised of (i) a latex of a polymer which is comprised of repeat units which are derived from (a) about 30 weight percent to about 84 weight percent vinyl aromatic moochers, (b) about 15 weight percent to about 65 weight percent alkyl acrylate moochers and (c) about 1 weight percent to about 6 weight percent unsaturated carbonyl group containing moochers, (ii) a coalescing solvent and (iii) a thickener; and (2) allowing the water-resistant coating composition to dry on the bottom side of said backing to produce the treated carpet which is impervious to aqueous liquids.

What is claimed is:  
     
       1. Carpet which is impervious to water which is comprised of a backing and a pile which is bonded to the top side of said backing, wherein the bottom side of said backing is coated with a polymer which is comprised of repeat units which are derived from (a) about 30 weight percent to about 84 weight percent vinyl aromatic monomers, (b) about 15 weight percent to about 65 weight percent alkyl acrylate monomers and (c) about 1 weight percent to about 6 weight percent unsaturated carbonyl group containing monomers. 
     
     
       2. A process for treating carpet which is comprised of a pile and a backing to render said carpet impervious to aqueous liquids, said process comprising the steps of (1) coating the bottom side of said backing with a water-resistant coating composition which is comprised of (i) a latex of a polymer which is comprised of repeat units which are derived from (a) about 30 weight percent to about 84 weight percent vinyl aromatic monomers, (b) about 15 weight percent to about 65 weight percent alkyl acrylate monomers and (c) about 1 weight percent to about 6 weight percent unsaturated carbonyl group containing monomers, (ii) a coalescing solvent and (iii) a thickener; and (2) allowing the water-resistant coating composition to dry on the bottom side of said backing to produce the treated carpet which is impervious to aqueous liquids. 
     
     
       3. A process as specified in  claim 2  wherein said water-resistant coating composition contains from about 10 phr to about 40 phr of said coalescing solvent. 
     
     
       4. A process as specified in  claim 3  wherein said water-resistant coating composition contains from about 10 phr to about 80 phr of said thickener. 
     
     
       5. A process as specified in  claim 4  wherein said water-resistant coating composition is further comprised of a plasticizer. 
     
     
       6. A process as specified in  claim 5  wherein said water-resistant coating composition contains up to about 20 phr of said plasticizer. 
     
     
       7. A process as specified in  claim 6  wherein said water-resistant coating composition contains from about 15 phr to about 35 phr of said coalescing solvent. 
     
     
       8. A process as specified in  claim 7  wherein said coalescing solvent is selected from the group consisting of ethylene glycol monobutyl ether, ethylene glycol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether and diethylene glycol monobutyl ether. 
     
     
       9. A process as specified in  claim 7  wherein said water-resistant coating composition contains from about 20 phr to about 60 phr of said thickener. 
     
     
       10. A process as specified in  claim 7  wherein said water-resistant coating composition contains from about 30 phr to about 50 phr of said thickener. 
     
     
       11. A process as specified in  claim 7  wherein said water-resistant coating composition contains from about 5 phr to about 15 phr of said plasticizer. 
     
     
       12. A process as specified in  claim 7  wherein said water-resistant coating composition contains from about 8 phr to about 12 phr of said plasticizer. 
     
     
       13. A process as specified in  claim 11  wherein said plasticizer is a liquid at room temperature and has a boiling point of at least 100° C. 
     
     
       14. A process as specified in  claim 13  wherein said plasticizer has a boiling point of at least 150° C. 
     
     
       15. A process as specified in  claim 7  wherein said latex contains a phosphate ester surfactant. 
     
     
       16. A process as specified in  claim 15  wherein said latex contains a water-insoluble nonionic surface active agent. 
     
     
       17. A process as specified in  claim 16  wherein said water-insoluble nonionic surface active agent is a fatty alcohol of the structural formula R-OH, wherein R represents an alkyl group containing from 5 to 22 carbon atoms. 
     
     
       18. A process as specified in  claim 16  wherein said water-insoluble nonionic surface active agent is a nonionic surfactant having a hydrophile-lipophile balance number of less than about 12. 
     
     
       19. A process as specified in  claim 16  wherein said water-insoluble nonionic surface active agent is a polyol having a molecular weight of at least about 1500.