摘要:
The present invention relates to (cyclo)aliphatic polyisocyanates which have a content of blocked and unblocked isocyanate groups (calculated a NCO) of 5 to 25 wt. %, in which at least 95% of the isocyanate groups are present in a form blocked with blocking agents, and which also contain 0.1 to 5.0 wt. % of amines having a structural unit corresponding to formula (I) The present invention also relates to the use of the blocked polyisocyanates according to the invention as crosslinking agents for organic polyhydroxyl compounds in 1C-PUR stoving lacquers, especially for automotive clearcoats and coil coating lacquers.
摘要:
The invention is directed to a process for the production of uretdione group-containing compounds by dimerizing at least a part of the isocyanate groups of organic isocyanates in the presence of compounds containing phosphorus-nitrogen bonds as dimerization catalysts, characterized in that the reaction is carried out in the presence, as co-catalysts, of H-active organic compounds having a pKa-value of at least 6, which have at least one hydrogen atom bound to oxygen, sulphur or nitrogen.The invention also relates to the uretdione group-containing compounds obtained according to this process and to their use for the production of plastics materials according to the isocyanate-polyaddition process.
摘要:
Polyisocyanates are prepared by thermally splitting a carbamate corresponding to the formula:R.sup.1 (NH--CO--O--R.sup.2).sub.nin which R.sup.1, R.sup.2 and n are as defined herein into the corresponding isocyanate and alcohol. The splitting reaction is carried out at a temperature of from 150.degree. to 350.degree. C., at a pressure of from 0.001 to 20 bar and in the presence of an auxiliary agent. Suitable auxiliary agents are hydrogen chloride, organic acid chlorides, compounds having an alkylating effect and organotin (IV) chlorides. Inert solvents and catalysts may also be employed in the splitting products. The thus-produced isocyanate and alcohol are then separated, if necessary.
摘要:
This invention relates to polyisocyanates which are partially or completely blocked with 3,5-dimethyl-1,2,4-triazole, to heat curable, one-component coating compositions containing these blocked polyisocyanates and to the resulting coatings.
摘要:
The present invention relates to colloidal metal oxides having blocked isocyanate groups, which are based on the reaction product ofA) blocked isocyanate group-containing silanes corresponding to formula (I) ##STR1## wherein R represents hydrogen or an organic group having 1 to 40 carbon atoms,X, Y and Z represent identical or different organic groups having 1 to 30 carbon atoms which are inert to isocyanate groups below 100.degree. C., provided that at least one of these groups is a C.sub.1 -C.sub.4 -alkoxy group,Q represents an organic group which contains at least one isocyanate group reacted with a blocking agent andn is 2, 3 or 4 withB) colloidal metal oxides selected from Al, Si, Ti, Ta, W, Hf, Zr, Sn and Y.The present invention also relates to the use of modified metal oxides, either alone or in combination with compounds containing at least two isocyanate-reactive groups, for the preparation of optionally expanded polyurethane plastics, lacquers or coating agents.
摘要:
The present invention relates to heat curable coating compositions containing a binder consisting essentially ofA) prepolymers which have butanone oxime-blocked isocyanate groups and are prepared fromA1) (cyclo)aliphatic polyisocyanates andA2) an organic polyhydroxyl component in whichA2.1 ) 50 to 90% of the hydroxyl equivalents of component A2) are from polyester polyols,A2.2) 10 to 50% of the hydroxyl equivalents of component A2) are from polyacrylate polyols and/or alkoxylation products of bisphenol A andA2.3) 0 to 30 of the hydroxyl equivalents of component A2) are from other organic polyhydroxyl compounds, andB) cycloaliphatic polyamines having at least two primary amino groups,wherein components A) and B) are present in an equivalent ratio of blocked isocyanate groups to amino groups of 1:0.8 to 1:1.2.The invention also relates to the use of these coating compositions for producing decorative, flying-stone-resistant, thick topcoats on metallic substrates.
摘要:
The present invention relates to an aqueous coating composition containing a) a urethane (meth)acrylate having (meth)acryloyl groups and optionally free isocyanate groups, b) optionally a further polyisocyanate, c) a UV initiator which initiates polymerization by a free radical mechanism, and d) one or more aqueous binders containing isocyanate-reactive groups. The present invention also relates to the use of the coating compositions for coating various substrates, especially metal substrates.
摘要:
The present invention relates to transparent coating compositions containing a binder and 0.5 to 25 wt. %, based on resin solids, of a material consisting of nanoscale primary particles obtained by jet dispersion of the nanoscale particles in the coating composition. The present invention also relates to a process for the production of these transparent coating compositions containing nanoscale particles by passing the coating compositions containing nanoscale primary particles and a binder in at least one pass through an apparatus which has at least one nozzle or at least one slit having a bore diameter or slit width of 0.05 to 1 mm and a length to diameter ratio of the bore or a depth to slit width ratio of the slit of 1 to 10, wherein there is a pressure differential between the nozzle inlet and outlet of at least 0.5, preferably of 1 MPa.
摘要:
The present invention relates to of a coating composition containing a moisture-hardening binder based on organic polyisocyanates which is prepared by forming a mixture containing at least those auxiliaries and additives which are not completely dry and an isocyanate component a) which has an average NCO functionality of 1.05 to 1.8 and is based on the reaction product ofa1) a polyisocyanate mixture of the diphenylmethane series witha2) a monohydric C.sub.1-26 alkanol which may contain ether bridges,and after the isocyanate/water reaction is substantially complete, further mixing the mixture with an isocyanate component b) which has an isocyanate content of 2.5 to 25% by weight and any remaining auxiliaries and additives, the quantities of components a) and b) corresponding to a weight ratio of a) to b) of 1:1 to 1:30.The present invention also relates to a process for the preparation of these coating compositions.
摘要:
This invention relates to a new one-component stoving composition, which can be baked at low temperatures without the release of volatile compounds and which also has satisfactory stability when stored at room temperature. The invention also relates to the use of the one-component stoving composition.