| 摘要 |
<p>1404849 Foam-backed carpets DOW CHEMICAL CO 15 Nov 1972 [17 Nov 1971] 52843/72 Heading B2E [Also in Divisions C3 and D1] A resilient foam backing of a pile carpet comprises synthetic resinous hollow expandable gas-filled microspheres with a glass transition temperature (Tg) of at least 50‹C in a synthetic resinous thermoplastic matrix having a Tg between -7‹C and +20‹C. The microspheres contain neopentane and have a shell of a co-polymer or polymer of styrene/acrylonitrile, methyl methacrylalate/ methyl acrylate or methyl methacrylate/acrylo nitrile. The matrix comprises a latex of styrene/ butadiene, vinylidene chloride/butyl acrylate/ acrylonitrile, isobutylacrylate/vinyl acetate or ethyl acrylate/styrene, with additions of sodium lauryl sulphate and the sodium salt of polyacrylic acid. Dyes, fillers, heat and light stabilisers, flame retardants and other additives may also be incorporated. A coating on the carpet back is heated between plates or parallel belts or without restriction, when its thickness is controlled by a doctor blade, to form a matrix and then expand the microspheres.</p> |
