Patent GB-1013014-A (GB)
Title: Packages containing calcium hypochlorite and the production of such packages
IPC: C11D3/395
Filed: 1962-07-20
Abstract: A device for producing an aqueous hypochlorite solution for bleaching or disinfecting purposes consists of a calcium hypochlorite composition contained in a porous envelope made from laid hypochlorite-resistant fibres having an air resistance between 0.01 and 25 seconds as determined by the test described in TAPPI method T460 m-49, the package being immersed in the water and the hypochlorite being dispersed at a rate controlled by the air resistance of the envelope material.  In one embodiment, the contents comprise calcium hypochlorite and inert diluent salts, e.g. sodium chloride.  In another, in which the device is used to disinfect a swimming pool, the inert diluent salts are replaced by a water-soluble salt such as sodium carbonate reactive with calcium hypochlorite to form a water-soluble hypochlorite and an insoluble precipitate, the latter being retained in the envelope. The envelope, whose wall thickness varies between a few mils and 0.03 inches, may be of fibres of glass or of a thermoplastic material such as nylon, polyethylene, polypropylene, polyethylene or terephthalate, the fibres being bonded by heat or by adhesive, e.g. sodium silicate, polyvinyl chloride or polymethyl methacrylate, sprayed thereon in a melted, dissolved, or suspended state.  The fibres may also be of asbestos and sprayed with melted polythene and heat-sealed. The envelope may be made by sealing all but one of the edges of a matching pair of sheets or of a single folded sheet, filling it, and sealing the remaining edge. A thread of a material resistant to concentrated aqueous hypochlorite may be attached to the envelope to suspend it in the water. In another embodiment, a continuous tube of the material is sealed at intervals and filled alternately with a calcium hypochlorite composition such as Ad-Dri bleach, and a detergent, the envelopes being severed in pairs for suspension in a washing machine. Specifications 806,564, 869,004 and U.S.A. Specification 2,829,110 are referred to.ALSO:A device for producing an aqueous hypochlorite solution for bleaching or disinfecting purposes consists of a calcium hypochlorite composition contained in a porous envelope made from laid hypochlorite-resistant fibres having an air-resistance between 0.01 and 25 seconds as determined by the test described in TAPPI method T460 m-49, the package being immersed in the water and the hypochlorite being dispersed at a rate controlled by the air-resistance of the envelope material.  In one embodiment, the contents comprise calcium hypochlorite and inert diluent salts, e.g. sodium chloride.  The envelope, whose wall thickness varies between a few mils and 0.03 inches, may be of fibres of glass or of a thermoplastic material such as nylon, polyethylene, polypropylene, polyethylene or terephthalate, the fibres being bonded by heat or by adhesive, e.g. sodium silicate, polyvinyl chloride or polymethyl methacrylate, sprayed thereon in a melted, dissolved, or suspended state.  The fibres may also be of asbestos and sprayed with melted polythene and heat-sealed.  The envelope may be made by sealing all but one of the edges of a matching pair of sheets or of a single folded sheet, filling it, and sealing the remaining edge.  A thread of a material resistant to concentrated aqueous hypochlorite may be attached to the envelope to suspend it in the water.  In another embodiment, a continuous tube of the material is sealed at intervals and filled alternately with a calcium hypochlorite composition such as Ad-Dri bleach, and a detergent, the envelopes being severed in pairs for suspension in a washing machine. Specifications 806,564, 869,004 and USA Specification 2,829,110 are referred to.ALSO:A device for producing an aqueous hypochlorite solution for bleaching or disinfecting purposes consists of a calcium hypochlorite composition contained in a porous envelope made from laid hypochlorite-resistant fibres having an air resistance between 0.01 and 25 seconds or detormed by the test described in TAPPI method T 460 m-49, the package being immersed in the water and the hypochlorite being dispersed at a rate controlled by the air resistance of the envelope material.  In one embodiment, the contents comprise calcium hypochlorite and inert diluent salts, e.g. sodium chloride.  In another, in which the device is used to disinfect a swimming pool, the inert diluent salts are replaced by a water-soluble salt such as sodium carbonate reactive with calcium hypochlorite to form a water-soluble hypochlorite and an insoluble precipitate, the latter being retained in the envelope. The envelope, whose wall thickness varies between a few mils and 0.03 inches, may be of fibres of glass or of a thermoplastic material such as nylon, polyethylene, polypropylene, polyethylene or terephthalate, the fibres being bonded by heat or by adhesive, e.g. sodium silicate, polyvinyl chloride or polymethyl methacrylate, sprayed thereon in a melted dissolved, or suspended state.  The fibres may also be of asbestos and sprayed with melted polythene and heat-sealed.  The envelope may be made by sealing all but one of the edges of a matching pair of sheets or of a single folded sheet, filling it, and sealing the remaining edge.  A thread of material resistant to concentrated aqueous hypochlorite may be attached to the envelope to suspend it in the water.  In another embodiment, a continuous tube of the material is sealed at intervals and filled alternately with a calcium hypochlorite composition such as Ad-Dri bleach, and a detergent, the envelopes being severed in pairs for suspension in a washing machine.  Specifications 806,564, 869,004 and U.S.A. 2,829,110 are referred to.