A process for producing a water-absorbing sheet material and the use thereof

• Main Authors: DAHMAN, KURT, HERRMANN, EDGAR, HOUBEN, JOCHEN
• Format: Patent
• Language: Chinese; English
• Published: 01.11.1999
• Subjects: AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F,C08G; AGRICULTURE; ANIMAL HUSBANDRY; BANDAGES, DRESSINGS OR ABSORBENT PADS; BRAIDING; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS, ORSURGICAL ARTICLES; CHEMISTRY; COMPOSITIONS BASED THEREON; COTTON-WOOL; CULTIVATION OF VEGETABLES, FLOWERS, RICE, FRUIT, VINES, HOPSOR SEAWEED; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF,TUBULAR STRUCTURES OF THE BODY, E.G. STENTS; DISINFECTION, STERILISATION, OR DEODORISATION OF AIR; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS,NON-WOVEN FABRICS; FILTERS IMPLANTABLE INTO BLOOD VESSELS; FIRST-AID KITS; FISHING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR; FOMENTATION; FORESTRY; GENERAL PROCESSES OF COMPOUNDING; HORTICULTURE; HUMAN NECESSITIES; HUNTING; HYGIENE; KNITTING; LACE-MAKING; LAUNDERING; MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVINGCARBON-TO-CARBON UNSATURATED BONDS; MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARYMATERIAL; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS, OR SURGICALARTICLES; MEDICAL OR VETERINARY SCIENCE; METALLURGY; METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS INGENERAL; NON-WOVEN FABRICS; ORGANIC MACROMOLECULAR COMPOUNDS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; PROSTHESES; TEXTILES; THEIR PREPARATION OR CHEMICAL WORKING-UP; TRAPPING; TREATMENT OF TEXTILES OR THE LIKE; TREATMENT OR PROTECTION OF EYES OR EARS; TREATMENT, NOT PROVIDED FOR ELSEWHERE IN CLASS D06, OF FIBRES, THREADS, YARNS,FABRICS, FEATHERS, OR FIBROUS GOODS MADE FROM SUCH MATERIALS; TRIMMINGS; WADDING; WATERING; WORKING-UP

The present invention relates to a process for producing water-absorbing sheet like materials which consists of a water-absorbent polymer and a prefabricated nonwoven fabric, wherein the prefabricated non-woven fabric is impregnated with a solution comprising partially neutralized acrylic acid and at least one cross linking agent and is squeezed to a certain coating amount, and the monomer solution thus applied to the non-woven substrate is the polymerized, which process is characterized in that the polymerization is carried out in the presence of radical initiators which can not be activated thermally and at least one thermally activatable radical former used in addition. The additional use of the thermally activatable radical former in the polymerization results in products having a low residual monomer content, an improved water absorption under load, and a higher retention, with a production method being employed the same time. The thermally activatable initiator portion may either be added to the monomer