摘要:
A process for the preparation of isocyanurate group-containing polyisocyanates in solvents which are inert towards isocyanate groups by reacting 0.2 to 1.5% of the isocyanate groups of diisocyanatotoluene with an aliphatic monohydric alcohol having 6 to 22 carbon atoms and subsequently trimerizing at least a portion of the isocyanate groups of the urethanized diisocyanates in the form of 40 to 70 wt. % solutions in lacquer solvents which are inert towards isocyanate groups, and the use of these polyisocyanates in two-component polyurethane coating compositions.
摘要:
Unsaturated polyesters of defined composition with a low content of polyalkylene glycol radicals in a narrow molecular weight range can be dispersed in water without external emulsifiers. These dispersions produce, after hardening, water and chemical resistant coatings with good mechanical properties.
摘要:
Water-dispersible polyisocyanate compositions based on aliphatic and aromatic diisocyanates and having an NCO content, based on solids, of 6 to 21% by weight, a weight ratio of incorporated TDI units to incorporated HDI units of 6:1 to 0.1:1 and a content of ethylene oxide units, arranged within terminal polyether chains, of 5 to 40% by weight; a method for the preparation of these polyisocyanate compositions by reacting a polyisocyanate component with monovalent polyether alcohols containing ethylene oxide units at an NCO/OH equivalent ratio of 2:1 to 120:1; and aqueous coating compositions containing these polyisocyanate compositions and polyhydroxyl compounds as the binder.
摘要:
A method for monitoring symmetrical two-wire bus lines and two-wire bus interfaces and a device for carrying out the method provides pulse weighting of low to high transitions or high to low transitions of the two wires operated in phase opposition of a two-wire bus line. The pulse chains thus obtained are used for step sequencing. In each case, one multistep shift function which is assigned to the first bus wire, is supplied with a first, constant logic read in state and can be reset to a second logic state in all-step fashion and, for all-step resetting of a similar second multistep shift function assigned to the second bus while, and vice versa, the step last achieved for each multistep shift function characterizing the respective fault state of the other bus wire. The pulse weighting is achieved by differentiation or high-pass filtering or by pulse generation controlled by state transition. For the pulse weighting, the device uses simple RC elements or edge-controlled monostable times, and for the multistep shift functions, two similar shift registers are used which can be loaded serially and clocked and reset in parallel and which can also be realized in one piece as a component of a monolithic semiconductor circuit by the previously mentioned elements. The device has a fault tolerance which can be programmed with respect to the bit width, and in conjunction with a likewise settable input cutoff frequency permits the decentralized local testing of two wire bus-type networks. The device can be made using CMOS technology, in conjunction with a very low space requirement.
摘要:
The present invention relates to hydrophilic polyurethanes having a content of (i) olefinic double bonds (expressed as C.dbd.C, molecular weight 24) of at least 1.0% by weight and (ii) ethylene oxide units incorporated through polyethylene glycol of 20 to 80% by weight, which are based on the reaction product ofa) 1.0 mole of a polyisocyanate component consisting of at least one organic polyisocyanate withb) 0.3 to 2.5 moles of at least one .beta.,.gamma.-ethylenically unsaturated ether alcohol containing 5 to 29 carbon atoms,c) 0 to 1.0 mole of at least one synthesis component containing at least two isocyanate-reactive groups and having a molecular weight of 62 to 2,000 andd) 0.25 to 0.85 moles of a polyethylene glycol component containing at least one polyethylene glycol having a molecular weight of 1,300 to 5,000,at an NCO/OH equivalent ratio, based on starting components a) to d), of 0.7:1 to 1.2:1.The present invention also relates to a water-dispersible coating composition based on a mixture of radical-curable synthetic resins containing unsaturated groups wherein the mixture containsA) 50 to 95 parts by weight of at least one non-water-dispersible synthetic resin containing unsaturated groups and having a molecular weight (M.sub.n of 500 to 10,000 andB) 5 to 95 parts by weight of a polyurethane component which possesses sufficient hydrophilicity to ensure the dispersibility of the mixture in water and which contains at least one of the previously mentioned hydrophilic polyurethanes.
摘要:
Opaquely pigmented coatings can be produced from lacquers based on monomer-free air-drying polyesters by means of UV radiation if hydroperoxides are additionally employed alongside UV initiators.
摘要:
The invention relates to an aqueous 2-component polyurethane (PU) coating composition comprising a vinyl polymer polyol dispersion, having a hydroxyl number between 10 and 264 mg KOH/g solid resin, an acid value (calculated from the sum of neutralized and non-neutralized acid groups) between 0 and 55 mg KOH/g solid resin, a number-average molecular weight Mn of at least 5000 g/mol and a weight average molecular weight Mw of at least 30,000 g/mol, a glass transition temperature of at least 20° C. and an average particle diameter of no greater than 300 nm, which is prepared in the presence of 0.1 to 10.0 wt. %, relative to the sum of the solids contents of polymer polyol and polyisocyanate, of a non-ionic polyether surfactant and a polyisocyanate having a viscosity at 23° C. of no more than 12,000 mPa*s and either a non-hydrophilic or a non-ionically or anionically hydrophilic character, whereby the equivalent ratio of isocyanate groups of component b) to hydroxyl groups of component a) is 0.2:1 to 5:1; a process for the preparation of such aqueous 2-component coating compositions, and their use as 2-component PU paints for painting any type of substrate.
摘要:
The present invention relates to storage stable, aqueous polyurethane-polyacrylate hybrid dispersions, which are self crosslinkable at room temperature and contain A) 10 to 95 wt. %, of a polyurethane dispersion,B) 5 to 90 wt. %, of a polymer prepared in the presence of component A) from a mixture of vinyl monomers containing 0.5 to 20 wt. %, based on the total resin solids content of the hybrid dispersion, of a vinyl monomer containing acetoacetoxy groups andC) an at least difunctional primary or secondary amine, which is present in an equivalent ratio of amino groups to acetoacetoxy groups of 0.5:1 to 1.1:1,in which the wt. % of components A) and B) add up to 100, based on the total weight of components A) and B).The present invention also relates to one-component coating compositions containing these hybrid dispersions as binders and to substrates coated with these coating compositions.
摘要:
Alkyd resin lacquers which contain cellulose nitric acid esters can be prevented from "lifting" and yellowing by the addition of bis-[hydroxyphenyl]-alkanes which are substituted in the nucleus.