The invention relates to aqueous two-component coating compositions based on preferably hydroxy-functional and/or amino-functional aqueous polymer dispersions and thioallophanates containing silane groups as crosslinking agents, to a method for producing them and to the use of these coating compositions for producing coatings.

The invention relates to coating agents that contain thioallophanates, containing silane groups, as cross-linking agents and to the use of said coating agents to produce coatings, in particular clear coats for automobile painting.

The present invention relates to a method for producing coatings on metal surfaces, wherein an optionally precoated metal surface has applied to it a coating material composition (K) which comprises a) at least one polyhydroxyl group-containing component (A), b) at least one component (B) having on average at least one free and/or blocked isocyanate group and having on average at least one hydrolyzable silane group of the formula (I)

N(XSiRx(OR)3-x)n(XSiRy(OR)3-y)m(I) c) and at least one phosphorus-containing catalyst (D) for the crosslinking of silane groups,
which comprises i. applying the coating material composition (K) to wheel rims, ii. 5 to 50 mol % of the isocyanate groups originally present in component (B) having undergone reaction to form silane groups of the formula (I), and iii. the phosphorus-containing catalyst (D) being selected from the group of phosphorus-containing acids and/or the partial esters of phosphorus-containing acids.

The present invention further provides the coatings obtainable by this method and also the use thereof.

The present invention relates to a method for producing dirt-repellent coatings on metal surfaces, more particularly on wheel rims, wherein an optionally precoated metal surface has applied to it a coating material composition (K) which comprises a) at least one polyhydroxyl group-containing component (A), b) at least one component (B) having on average at least one isocyanate group and having on average at least one hydrolyzable silane group of the formula (I)

XSiR.sup.3.sub.sG.sub.3-s(I) where G=identical or different hydrolyzable groups, X=organic radical, R.sup.3=alkyl, cycloalkyl, aryl, or aralkyl, it being possible for the carbon chain to be interrupted by nonadjacent oxygen, sulfur, or NRa groups, with Ra=alkyl, cycloalkyl, aryl, or aralkyl, s=0 to 2, c) at least one phosphorus- and nitrogen-containing catalyst (D) for the crosslinking of silane groups, and d) at least one catalyst (Z) for the reaction of the hydroxyl groups with the isocyanate groups,
which comprises the catalyst (Z) being selected from the group of zinc and bismuth carboxylates, of aluminum, zirconium, titanium and/or boron chelates, of inorganic, tin-containing catalysts, and of mixtures thereof.

The present invention further provides the coatings obtainable by this method and also the use thereof.

A reaction product containing urethane groups, comprising one or more species of the general formula (I)

(R.sup.1X).sub.pZ.sup.1(XH).sub.y(I) where p+y=w and w is an integer from 2 to 10, p is an integer from 2 to 10, y is an integer from 0 to 8, and X is independently O, NH and/or NZ.sup.2 and XH is independently a hydroxyl group OH, a primary amino group NH.sub.2 and/or a secondary amino group NHZ.sup.2 where Z.sup.2 is independently a branched or unbranched, saturated or unsaturated organic radical G(U).sub.a where U is independently a hydroxyl group, a primary amino group or a secondary amino group and a is an integer from 0 to 8, where w+a10, G is a branched or unbranched, saturated or unsaturated organic radical, the p R.sup.1 radicals are independently a radical of the general formula (II)

YOCONHR.sup.2NHCO(II)

in which the p Y radicals are independently a branched or unbranched, saturated or unsaturated organic radical which has 1 to 1000 carbon atoms and does not contain any hydroxyl groups, any primary amino groups or any secondary amino groups, the p R.sup.2 radicals are independently a branched or unbranched, saturated or unsaturated organic radical having 6 to 20 carbon atoms, and Z.sup.1 is a branched or unbranched, saturated or unsaturated organic radical which contains at least one tertiary nitrogen group and is free of XH groups.

A moisture-cured hot-melt adhesive can be formulated as a PUR-HM that is R-40 classification-free and stable during storage and processing, having a residual monomer content of less than 1 wt. % and having good cross-linking density and full-curing speed. The hot-melt adhesive is particularly suitable for vehicle construction in industrial manufacture, in particular of automobiles, in the textile or furniture industry or in the packaging industry.

The invention relates to modified polyisocyanates, obtained by reacting at least one polyisocyanate (A) based on 1,5-diisocyanatopentane with at least one silane compound (B) which is reactive with respect to isocyanate groups. The invention also relates to a method for producing the modified polyisocyanates and to the use thereof as starting components in the production of polyurethane plastics, in particular as crosslinker components in polyurethane paints and coatings.

Disclosed are nonaqueous coating material compositions comprising (A) at least one polyhydroxyl-group-containing compound, (B) at least one polyisocyanate-group-containing compound having free or blocked isocyanate groups, and (D) at least one catalyst for the crosslinking of silane groups, where component (B) comprises at least one structural unit
NR(XSiRx(OR)3x)(I), and at least one structural unit
N(XSiRx(OR)3x)n(XSiRy(OR)3y)m(II), wherein in component (B) (i) more than 30 mol % and less than 70 mol % of the originally present isocyanate groups have undergone reaction to form structural units (I) and (II), (ii) more than 25 and less than 36 mol % of the originally present isocyanate groups have undergone reaction to form structural units (II), and (iii) component (B) has at least one polyisocyanate group-containing compound (B2) having free or blocked isocyanate groups and having an acyclic, aliphatic polyisocyanate parent structure.

One of the purposes of the present invention is to provide a blocking agent for blocking an isocyanate group to thereby prepare an isocyanate compound which has excellent water resistance and is react with another polymerizable compound to be cured at a relatively low temperature; and another purpose is to provide a blocked isocyanate having an isocyanate group blocked with the blocking agent. The present invention provides a blocking agent for blocking an isocyanate group, wherein the blocking agent is an organic silicon alcohol having an organic group bonded to a silicon atom and said organic group is capable of forming a -silyl cation together with the silicon atom. In a preferred embodiment, the present invention provides a blocking agent which is an organic silicon alcohol represented by the general formula (1). In the formula (1), R.sup.1 is an alkylene group having 3 to 5 carbon atoms and may have a substituent, provided that the number of carbon atoms of the substituent is not included in the number of the carbon atoms of the alkylene group, R.sup.2 is an alkyl group having 1 to 10 carbon atoms, Z is an organic group capable of forming a -silyl cation together with the silicon atom to which Z bonds, and n is an integer of 1 to 3. The present invention further provides a blocked isocyanate having a structure in which the isocyanate group is blocked with the aforesaid blocking agent and a thermosetting composition comprising the blocked isocyanate.

Disclosed herein are stable organosiloxane coating compositions comprising a blocked isocyanate silane and at least one polyol that provide abrasion resistant coatings for transparent polymer substrates. The cured coatings also have excellent adhesion to the polymer substrates. In accordance with certain embodiments, the disclosed coating compositions, which when cured on the substrate, provide formable, weatherable, anti-fog, or combinations of formable, weatherable, or anti-fog organosiloxane coatings. Also disclosed herein are articles comprising coatings cured from such coating compositions, and processes for making the coating compositions.