摘要:
The invention relates to a cathodic electro-dipping process wherein the electro-dipping primer employed contains a crosslinking agent which can be obtained by(I) reacting, in a first stage,(a) diphenylmethane diisocyanate and(b) a monoalcohol or a mixture of monoalcohols to give an intermediate product (A) containing isocyanate groups, and(II) reacting this intermediate product (A) in a second stage with(c) a polyol or a mixture of polyols to give an intermediate product (B) containing hydroxyl groups which(III) is reacted in a third stage either with(d) a cycloaliphatic, aliphatic or araliphatic polyisocyanate or a mixture of such polyisocyanates and(e) a monofunctional masking agent or a mixture of such masking agents or with(f) a partially-masked polyisocyanate prepared from (d) and (e)to give a crosslinking agent which is free from isocyanate groups.
摘要:
The invention relates to a cathodic electro-dipcoating process, wherein the electro-dipcoating composition used contains a cationic, amine-modified epoxy resin, which is obtainable by reacting(A) a polyepoxide,(B) an amine and(C) an adduct, which is obtainable by . . . (sic)(c1) a polyether- or polyester-polyol,(c2) a polyisocyanate and(c3) a compound which contains at least one hydrogen atom which is reactive towards isocyanate groups and at least one ketimine group in the molecule, and/or(D) a hydrolysis product of (C)with one another in a relative proportion such that 20 to 90% of the epoxy groups of component (A) are reacted with component (B) and the remaining epoxy groups are reacted with component (C) and/or (D), and--if still necessary--at least partially protonating the reaction product thus obtained.
摘要:
In order to increase the stone chip resistance of automobile finishes aqueous electrocoating paints are used which are produced by the use of a pigment paste which contains as grinding resin an at least partially protonated epoxide-amine adduct which is obtainable by reacting(A) a glycidyl ether of a polyphenol which contains on statistical average at least one epoxide group in the molecule, or a mixture of such glycidyl ethers,(B) a polyglycidyl ether of a polyol which contains on statistical average more than 1.0 epoxide groups in the molecule, or a mixture of such polyglycidyl ethers, and(C) a compound which contains a primary amino group in the molecule or a mixture of such compoundswith each other in such a stoichiometric ratio that an epoxide-amine adduct is obtained in which on statistical average at least 2.0 primary amino groups of the component (C) are incorporated in a chain-extending function with the formation of tertiary amino groups and the resultant epoxide-amine addict is at least partially protonated.
摘要:
The invention relates to a cathodic electro-dipping process, which comprises a procedure in which the electro-dipping primer used contains an adduct containing urethane groups which is obtainable by reacting with one another a polyester-polyol or polyether-polyol, a polyisocyanate and a compound which contains a hydroxyl group and at least one ketimine group in the molecule.
摘要:
The invention relates to a cathodic electro-dipping process wherein the electro-dipping primer employed contains a crosslinking agent which can be obtained by(I) reacting, in a first stage,(a) diphenylmethane diisocyanate and(b) a monoalcohol or a mixture of monoalcohols to give an intermediate product (A) containing isocyanate groups, and(II) reacting this intermediate product (A) in a second stage with(c) a polyol or a mixture of polyols to give an intermediate product (B) containing hydroxyl groups which(III) is reacted in a third stage either with(d) a cycloaliphatic, aliphatic or araliphatic polyisocyanate or a mixture of such polyisocyanates and(e) a monofunctional masking agent or a mixture of such masking agents or with(f) a partially-masked polyisocyanate prepared from (d) and (e)to give a crosslinking agent which is free from isocyanate groups.
摘要:
The invention relates to a cathodic electrocoating process, which uses electrocoating baths which contain a cationc amine-modified epoxy resin otainable by reacting(A) a diepoxy compound of an epoxy equivalent weight below 2000B) a compound monofunctionally reactive toward the epoxide groups and containign an alcoholic OH group, a phenolic OH group or an SH group, and(C) an amine,the components (A) and (B) being used in molar ratio of 10:1 to 1:1, preferably 4:1 to 1.5:1 and the positive charges being introduced by protonization of the reaction product and/or by use of amine salts as the component (C). The electrocoating baths used are distinguished by containing at least 7.5% by weight of a polyoxyalkylenepolyamine, the percentage by weight referring to the total amount of binders contained in the electrocoating bath.
摘要:
The invention relates to a process for a cathodic electrocoating process, wherein the electrocoating bath contains at least 7.5% by weight of a polyoxyalkylenepolyamine or a mixture consisting of several polyoxyalkylenepolyamines of different chemical structures, the percentage by weight referring to the total amount of binders contained in the electrocoating bath.
摘要:
The invention relates to a cathodic electro-dipping process wherein the electro-dipping primer employed contains a crosslinking agent which can be obtained by reactinga) a diol and/or a triol or a mixture of diols and/or a mixture of triols,b) diphenylmethane 4,4'-diisocyanate the melting point of which has been depressed, by partial reaction with a monool and/or polyol or a mixture of monools and/or a mixture of polyols, so far that it is liquid at room temperature andc) a masking agent or a mixture of masking agentsto give a crosslinking agent which is free from isocyanate groups.
摘要:
The present invention relates to a process for the multilayer coating of substrates with electrodeposition and powder coating materials, in which electrodeposition is used to apply at least one coat (2) of electrodeposition coating material to the substrate (1), after deposition the substrate (1) is, if desired, wholly or partially air-dried, a coat of powder coating material (3) is then applied, and finally electrodeposition coating material and powder coating material are jointly baked.
摘要:
The invention relates to three-layer metal pipe coating compositions based on a powder primer, on a thermoplastic hard adhesive and on a polyolefin cladding. The powder primer contains epoxidized novolak resins, phenolic crosslinking agents and fillers based on crystalline silicic acid modifications. The invention likewise relates to a process for the exterior coating of metal pipes by a three-layer method, in which the powder primer described is applied to the metal pipe, a thermoplastic hard adhesive is applied to the powder primer, and subsequently a polyolefin cladding is applied.