| abstract |
745,030. Compound filter paper; laminated materials. JOHNSON & JOHNSON. Dec. 11, 1953 [Dec. 11, 1952], No. 34606/53. Classes 96 and 140. A disposable filter paper laminate, e.g. for suction cleaner bags, or filtering viscose, has a ply or plies 11, e.g. of creped cellulose tissue paper, and a ply or plies 10 of textile fibres, and may have another ply 12, of textile fibres, the weights of the plies 10 and 11 being respectively 400 to 1600, and 200 to 1000 grains per square yard, and their porosities such that if air flows through them at a speed of 116 ft. per min. there is a pressure drop of 0.01 to 0.06, and 0.5 to 2.0 inches of water per 100 grains per square yard weight of the respective plies, the laminate being bonded with up to 15 per cent of e.g. polyvinyl alcohol, -acetate, or -chloride, synthetic rubber, starch, dextrin, or gum arabic. The textile fibres may be cotton, or other natural fibres, or synthetic filaments. |