Water-soluble coating materials

In a method for preparing a coating material comprising water, a water-soluble, organic solvent and a water-soluble, thermosetting resin, which resin is a mixture of (A) 4 to 50 parts by weight of an amino resin and (B) a water-soluble salt of 100 parts by weight of a copolymer with 0.5 to 2.0 equivalents of an amine with respect to carboxyl groups is said copolymer, the improvement wherein said method comprises:

• 1. reacting at a temperature of 100.degree. to 160.degree.C an .alpha.,.beta.-ethylenically unsaturated carboxylic acid having 3 to 5 carbon atoms with a polyglycidyl polyether of a dihydric phenol, said polyglycidyl polyether having at least two epoxy groups, in a proportion of 0.01 to 0.5 equivalent of the polyglycidyl polyether with respect to the carboxyl group contained in the acid until at least 10% of the epoxy groups are reacted with said acid,
• 2. subjecting the resulting reaction product to copolymerization in the presence of a polymerization initiator with at least one hydroxy-free, polymerizable, unsaturated monomer having 2 to 30 carbon atoms in an amount of 50 to 80.5 parts by weight per 19.5 to 50 parts by weight of said reaction product at a temperature of 40.degree. to 160.degree.C,
• 3. neutralizing the resulting copolymer with said amine to form said water-soluble salt of the copolymer, and
• 4. then mixing said salt with said water-soluble amino resin.

In a method for preparing a coating material comprising water, a water-soluble, organic solvent and a water-soluble, thermosetting resin, which resin is mixture of (A) 4 to 50 parts by weight of an amino resin and (B) a water-soluble salt of 100 parts by weight of a copolymer with 0.5 to 2.0 equivalent of an amine with respect to carboxyl groups in said copolymer, the improvement wherein said method comprises:

• 1. subjecting a mixture of an .alpha.,.beta.-ethylenically unsaturated carboxylic acid and at least one hydroxy-free, polymerizable, unsaturated monomer having 2 to 30 carbon atoms to copolymerization in the presence of a polymerization initiator at a temperature of 40.degree. to 160.degree.C,
• 2. reacting the resulting copolymer with a polyglycidyl polyether of a dihydric phenol, said polyglycidyl polyether having at least two epoxy groups, in a proportion of 0.01 to 0.5 equivalent of the polyglycidyl polyether with respect to the carboxyl group contained in the acid at a temperature of 100.degree. to 160.degree.C, the total amount of said acid and said polyglycidyl polyether being 19.5 to 50 parts by weight per 50 to 80.5 parts by weight of said hydroxy-free, polymerizable, unsaturated monomer, until at least 10% of the epoxy groups are reacted with the carboxyl groups of said copolymer,
• 3. neutralizing the resulting copolymer with said amine to form said water-soluble salt of the copolymer, and
• 4. then mixing said salt with said water-soluble amino resin.

In a method for preparing a coating material comprising water, a water-soluble, organic solvent and a water-soluble, thermosetting resin, which resin is a mixture of (A) 4 to 50 parts by weight of an amino resin and (B) a water-soluble salt of 100 parts by weight of a copolymer with 0.5 to 2.0 equivalents of an amine with respect to carboxyl groups in said copolymer, the improvement wherein said method comprises:

• 1. reacting an .alpha.,.beta.-ethylenically unsaturated carboxylic acid having 3 to 5 carbon atoms with a polyglycidyl polyether of a dihydric phenol, said polyglycidyl polyether having at least two epoxy groups, in a proportion of 0.01 to 0.5 equivalent of the polyglycidyl polyether with respect to the carboxyl group contained in the acid at a temperature of 100.degree. to 160.degree.C until at least 10% of the epoxy groups are reacted with said acid,
• 2. subjecting 19.5 to 50 parts by weight of the resulting reaction product to copolymerization in the presence of a polymerization initiator at a temperature of 40.degree. to 160.degree.C with 50 to 80.5 parts by weight of at least one hydroxy-free, polymerizable, unsaturated monomer having 2 to 30 carbon atoms and up to 30 parts by weight of at least one polymerizable, unsaturated monomer having a hydroxyl group and 3 to 8 carbon atoms, the total amount of the reaction product, the hydroxy-free, polymerizable, unsaturated monomer and the hydroxy-containing polymerizable, unsaturated monomer being 100 parts by weight,
• 3. neutralizing the resulting copolymer with said amine to form said water-soluble salt of the copolymer, and
• 4. then mixing said salt with said water-soluble amino resin.

In a method for preparing a coating material comprising water, a water-soluble, organic solvent and a water-soluble, thermosetting resin, which resin is a mixture of (A) 4 to 50 parts by weight of an amino resin and (B) a water-soluble salt of 100 parts by weight of a copolymer with 0.5 to 2.0 equivalents of an amine with respect to carboxyl groups in said copolymer, the improvement wherein said method comprises:

• 1. subjecting a mixture of an .alpha.,.beta.-ethylenically unsaturated carboxylic acid having 3 to 5 carbon atoms, at least one hydroxy-free, polymerizable, unsaturated monomer having to 2 to 30 carbon atoms and at least one polymerizable unsaturated monomer having a hydroxyl group and 3 to 8 carbon atoms to copolymerization in the presence of a polymerization initiator at a temperature of 40.degree. to 160.degree.C,
• 2. reacting at a temperature of 100.degree. to 160.degree.C the resulting copolymer with a polyglycidyl polyether of a dihydric phenol, said polydlycidyl polyether having at least two epoxy groups, the proportion of the polyglycidyl polyether being 0.01 to 0.5 equivalent with respect to the carboxyl group contained in said acid, the total amount of said acid and said polyglycidyl polyether being 19.5 to 50 parts by weight per 50 to 80.5 parts by weight of said hydroxy-free, polymerizable unsaturated monomer and the amount of the hydroxy-containing polymerizable unsaturated monomer being up to 30 parts by weight, the total amount of the acid, the polyglycidyl polyether, the hydroxy-free monomer and the hydroxy-containing monomer being 100 parts by weight, until at least 10% of the epoxy groups are reacted with the carboxyl groups of said copolymer,
• 3. neutralizing the resulting copolymer with said amine to form said water-soluble salt of the copolymer, and
• 4. then mixing said salt with said water-soluble amino resin.

In a method for preparing a coating material comprising water, a water-soluble, organic solvent and a water-soluble, thermosetting resin, which resin is a mixture of (A) 4 to 50 parts by weight of an amino resin and (B) a water-soluble salt of 100 parts by weight of a copolymer with 0.5 to 2.0 equivalents of an amine with respect to carboxyl groups in said copolymer, the improvement wherein said method comprises:

• 1. heating at a temperature of 100.degree. to 160.degree.C a mixture of an .alpha.,.beta.-ethylenically unsaturated carboxylic acid having 3 to 5 carbon atoms;
• a polyglycidyl polyether of a dihydric phenol;
• said polyglycidyl polyether having at least two epoxy groups, the proportion of said acid and said polyglycidyl polyether being 0.1 to 0.5 equivalent of the polyglycidyl polyether with respect to the carboxyl group contained in the acid, the total amount of said two components being 19.5 to 50 parts by weight;
• 50 to 80.5 parts by weight of at least one hydroxy-free, polymerizable, unsaturated monomer having 2 to 30 carbon atoms;
• and up to 30 parts by weight of at least one polymerizable, unsaturated monomer having a hydroxyl group and 3 to 8 carbon atoms, the total amount of the acid, the polyglycidyl polyether, the hydroxy-free monomer and the hydroxy-containing monomer being 100 parts by weight, to effect simultaneously copolymerization and reaction of the carboxyl groups with the epoxy groups,
• 2. neutralizing the resulting copolymer with said amine to form said water-soluble salt of the copolymer, and
• 3. then mixing said salt with said water-soluble amino resin.