The present, invention aims to provide an additive which has a reactive group with good active energy ray curability. When incorporated in a paint, the additive does not bleed over time and imparts an excellent leveling property and a defoaming property to the paint. There is provided a (meth)acrylic-modified siloxane compound of formula (a1) which has, as a branch and, optionally, at one or both of the terminals, of a linear polysiloxane backbone, a specific number of moieties having a (meth)acryloyl group at a terminal and a (poly)oxyalkylene structure of the formula —(C.sub.aH.sub.2aO).sub.b—. Also provided is an additive for paints, comprising said (meth)acrylic-modified siloxane compound.

A polyether-modified siloxane represented by an average composition formula (1): (R.sub.3SiO.sub.1/2).sub.a(R.sub.2R′SiO.sub.1/2).sub.a′(R.sub.2SiO.sub.2/2).sub.b(RR′SiO.sub.2/2).sub.b′(RSiO.sub.3/2).sub.c(SiO.sub.4/2).sub.d. In the formula (1), “R”s each represent a hydrogen atom, a hydroxy group, a monovalent hydrocarbon group having 1 to 18 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms, “R” 's each represent an organic group selected from groups represented by —C.sub.qH.sub.2q—O—(C.sub.2H.sub.4O).sub.e(C.sub.3H.sub.6O).sub.f—R.sup.1, R.sup.1s each represent a hydrogen atom, a hydrocarbon group having 1 to 30 carbon atoms, or an organic group represented by R.sup.6—(CO)—, and R.sup.6 represents a hydrocarbon group having 1 to 30 carbon atoms. This can provide a novel polyether-modified siloxane that has little environmental impact and that provides excellent antifouling performance.

A water-repellent coating composition, and particularly, a water-repellent coating composition having improved adhesion and durability by including a phosphoric acid or a phosphoric acid-based compound, is provided.

Sidechain functionalized organosiloxane compounds are provided having a first end and a second end; a polysiloxane backbone; and a first plurality of sidechains covalently attached to the polysiloxane backbone and a second plurality of sidechains covalently attached to the polysiloxane backbone; wherein the first plurality of sidechains comprise polyalkylene glycol sidechains; wherein the first plurality of sidechains and the second plurality of sidechains comprise a tethered end covalently attached to the polysiloxane backbone and a free end opposite to the tethered end; and wherein the free end in one or both of the first plurality of sidechains and the second plurality of sidechains comprises a reactive end group. Compositions comprising the sidechain functionalized organosiloxane compounds are also provided, as well as coated articles. Sidechain functionalized lubricants are also provided that can be used with compositions and coated articles herein.

Sidechain functionalized organosiloxane compounds are provided having a first end and a second end; a polysiloxane backbone; and a first plurality of sidechains covalently attached to the polysiloxane backbone and a second plurality of sidechains covalently attached to the polysiloxane backbone; wherein the first plurality of sidechains comprise polyalkylene glycol sidechains; wherein the first plurality of sidechains and the second plurality of sidechains comprise a tethered end covalently attached to the polysiloxane backbone and a free end opposite to the tethered end; and wherein the free end in one or both of the first plurality of sidechains and the second plurality of sidechains comprises a reactive end group. Compositions comprising the sidechain functionalized organosiloxane compounds are also provided, as well as coated articles. Sidechain functionalized lubricants are also provided that can be used with compositions and coated articles herein.

An aqueous coating additive containing a polyether-modified siloxane represented by an average composition formula (1): (R.sub.3SiO.sub.1/2).sub.a(R.sub.2R′SiO.sub.1/2).sub.a′(R.sub.2SiO.sub.2/2).sub.b(RR′SiO.sub.2/2).sub.b′(RSiO.sub.3/2).sub.c(SiO.sub.4/2).sub.d. “R”'s each represent an organic group selected from groups represented by —C.sub.qH.sub.2q—O—(C.sub.2H.sub.4O).sub.e(C.sub.3H.sub.6O).sub.f—R.sup.1. The R′ groups satisfy expression (I): 5≤{(molecular weight of the —C.sub.2H.sub.4O— moiety)/(molecular weight of an entire polyether-modified siloxane)}×20≤10; and expression (II): {(molecular weight of the —C.sub.3H.sub.6O— moiety)/(molecular weight of the —C.sub.2H.sub.4O— moiety)}≤1.0. This provides an additive for an aqueous coating and an aqueous coating composition that have little environmental impact and that provide excellent antifouling performance.

An aqueous coating additive containing a polyether-modified siloxane represented by an average composition formula (1): (R.sub.3SiO.sub.1/2).sub.a(R.sub.2R′SiO.sub.1/2).sub.a′(R.sub.2SiO.sub.2/2).sub.b(RR′SiO.sub.2/2).sub.b′(RSiO.sub.3/2).sub.c(SiO.sub.4/2).sub.d. “R”'s each represent an organic group selected from groups represented by —C.sub.qH.sub.2q—O—(C.sub.2H.sub.4O).sub.e(C.sub.3H.sub.6O).sub.f—R.sup.1. The R′ groups satisfy expression (I): 5≤{(molecular weight of the —C.sub.2H.sub.4O— moiety)/(molecular weight of an entire polyether-modified siloxane)}×20≤10; and expression (II): {(molecular weight of the —C.sub.3H.sub.6O— moiety)/(molecular weight of the —C.sub.2H.sub.4O— moiety)}≤1.0. This provides an additive for an aqueous coating and an aqueous coating composition that have little environmental impact and that provide excellent antifouling performance.

The present invention is directed towards an electrodepositable coating composition comprising, consisting essentially of, or consisting of an ionic salt group-containing silicone-based main film-forming polymer comprising functional groups; and a curing agent reactive with the functional groups of the ionic salt group-containing silicone-based main film-forming polymer. Also disclosed are coatings, coated substrates, and methods of coating a substrate.

The present invention is directed towards an electrodepositable coating composition comprising, consisting essentially of, or consisting of an ionic salt group-containing silicone-based main film-forming polymer comprising functional groups; and a curing agent reactive with the functional groups of the ionic salt group-containing silicone-based main film-forming polymer. Also disclosed are coatings, coated substrates, and methods of coating a substrate.

A (meth)acrylic copolymer of the present invention includes a constituent unit (B) derived from a polysiloxane block-containing polymerizable monomer (b) represented by Formula (b1). In Formula (b1), R.sup.30 represents a hydrogen atom or a methyl group, a represents an integer of 2 to 5, b represents a number of 0 to 50, c represents an integer of 0 to 18, d represents a number of 1 to 1000, e represents a number of 1 to 80, R.sup.31 to R.sup.39 each represents an alkyl group, an alkoxy group, a phenyl group, a substituted phenyl group, a phenoxy group, or a substituted phenoxy group.