Abstract: A capacitive proximity switch for detecting the change in the capacitance relative to a setpoint capacitance by the approach or retreat of an object in the sensitive area of a proximity switch, especially for use in the door handle of a motor vehicle, provides reliable error detection and error suppression at a fundamentally high sensitivity of the capacitive proximity switch by utilizing an evaluation unit that evaluates a measured value of the change in capacitance over time and depending on the time behavior of the measured value activates changes the operating threshold from a first threshold (which can be caused by a false object coming into or out of the sensitive area of the proximity switch) to a higher second threshold which can be reached only at a relatively greater change in capacitance caused by a target object coming into or out of the sensitive area of the proximity switch.

Abstract: The invention provides non-stick coated molds, a process for the preparation thereof and their use for the production of plastics molded parts, particularly for the production of molded parts made of polyurethane foam.

Abstract: A capacitive proximity switch for detecting the change in the capacitance relative to a setpoint capacitance by the approach or retreat of an object in the sensitive area of a proximity switch, especially for use in the door handle of a motor vehicle, provides reliable error detection and error suppression at a fundamentally high sensitivity of the capacitive proximity switch by utilizing an evaluation unit that evaluates a measured value of the change in capacitance over time and depending on the time behavior of the measured value activates changes the operating threshold from a first threshold (which can be caused by a false object coming into or out of the sensitive area of the proximity switch) to a higher second threshold which can be reached only at a relatively greater change in capacitance caused by a target object coming into or out of the sensitive area of the proximity switch.

Abstract: The invention provides non-stick coated molds, a process for the preparation thereof and their use for the production of plastics molded parts, particularly for the production of molded parts made of polyurethane foam.

Abstract: The description relates to production of rigid foamed plastics containing urethane groups, by use of a blowing-agent mixture containing 5 to 50 parts by weight of C3 and/or C4 alkanes and 50 to 95 parts by weight of cyclopentane. There is also a description of use of the thus-produced rigid foamed plastics as composite components or for foam filling of cavities in refrigerator construction.

Abstract: The present invention relates to a process for the production of partially fluorinated fluoropolymers, in accordance with which fluoromonomers are free-radically polymerized in the presence of polyfluoropropanes or polyfluorobutanes of the formulae CF3—CH2—CF2H, CF3—CHF—CF2—H, CF3—CH2—CF3, CHF2—CF2—CH2F, CF3—CH2—CF2—CH3 AND CF3—CHF—CF2—CH3 and optionally a chain-transfer agent.

Abstract: A process for preparing rigid expanded materials containing urethane and optionally urea and isocyanurate groups, characterised in that a polyurethane rigid foam is prepared by reactinga) an aromatic polyisocyanate withb) a polyol component with on average at least 3 hydrogen atoms which can react with isocyanates, containing1) 30 to 80 wt. % of an aromatic amine started polyether with a molecular weight of 300 to 800 based on 70 to 100 wt. % of 1,2-propylene oxide and 0 to 30 wt. % of ethylene oxide2) 10 to 40 wt. % of a substantially sucrose started polyether with a molecular weight of 400 to 1,000 based on 70 to 100 wt. % of 1,2-propylene oxide and 0 to 30 wt. % of ethylene oxide3) 5 to 30 wt. % of a propylene glycol started polyether with a molecular weight of 500 to 1,500 based on 70 to 100 wt. % of 1,2-propylene oxide and 0 to 30 wt. % of ethylene oxide4) n-pentane and/or i-pentane as blowing agent5) water6) optional auxiliary agents and additives,wherein the sum of the wt.

Abstract: Rigid polyurethane foams are produced by reacting a polyisocyanate with a polyester containing at least two isocyanate-reactive hydrogen atoms and having a molecular weight of 400 to 10,000 in the presence of water, an organic blowing agent, a flameproofing agent and a compound containing at least two isocyanate-reactive hydrogen atoms and having a molecular weight in the range from 32 to 399 as crosslinking agent, optionally in the presence of known auxiliaries and additives. The polyester, the flameproofing agent and the crosslinking agent are used in quantities such that from about 15 to about 35 parts by weight of polyester, from about 50 to about 80 parts by weight flameproofing agent and from about 5 to about 15 parts by weight of crosslinking agent (with the sum of the parts by weight of these components adding up to 100) are present. These foams are useful as insulating materials in applications where flame resistance is important.

Abstract: Rigid foams containing urethane and isocyanurate groups are made by reacting a polyisocyanate with a compound containing at least two isocyanate reactive hydrogen atoms in the presence of an aqueous solution of alkali metal carboxylate in accordance with known techniques. The aqueous alkali metal carboxylate solution has an alkali metal carboxylate content of from about 10 to about 50% by weight. The alkali metal carboxylates are preferably alkali metal acetates such as potassium acetate. This process is carried out at an index above 150. The product foams are particularly useful as insulating materials.

Abstract: This invention relates to novel urethane-modified polyisocyanate mixtures of the diphenylmethane series prepared by a process comprising reacting polyisocyanates or polyisocyanate mixtures of the diphenylmethane series with certain monohydric and/or polyhydric alcohols and, optionally, subsequently mixing the initially modified products with polyisocyanates or polyisocyanate mixtures of the diphenylmethane series that have not been modified with urethane groups. This invention further relates to the use of the polyisocyanate mixtures in the preparation of polyurethane foams.