초록 ▼

Aqueous coating compositions are described where the binder includes an anionically stabilized polymeric dispersion. The monomers used to prepare the dispersion are acrylic acid and methacrylic acid as a carboxylic monomer and styrene, alpha methyl styrene or vinyl toluene as a hydrophobic high Tg a

Aqueous coating compositions are described where the binder includes an anionically stabilized polymeric dispersion. The monomers used to prepare the dispersion are acrylic acid and methacrylic acid as a carboxylic monomer and styrene, alpha methyl styrene or vinyl toluene as a hydrophobic high Tg aromatic monomer and an alkyl acrylate ester as a low Tg monomer. The relative weight proportions of the monomers are required to satisfy a formula. Blends of high and low Tg dispersions are also described. Paints formulated with the binders exhibit an excellent balance of stain resistance, tint strength and viscosity stability.

대표청구항 ▼

The claims of the invention are as follows: 1. A water-borne domestic household paint composition comprising an anionically stabilised dispersion polymerised from: a) a carboxylic acid containing ethylenically unsaturated monomer selected from the group consisting of acrylic acid, methacrylic acid

The claims of the invention are as follows: 1. A water-borne domestic household paint composition comprising an anionically stabilised dispersion polymerised from: a) a carboxylic acid containing ethylenically unsaturated monomer selected from the group consisting of acrylic acid, methacrylic acid and mixtures thereof; b) a hydrophobic aromatic ethylenically unsaturated high glass transition temperature ("Tg") monomer selected from the group consisting of styrene and alpha methyl styrene; and c) a C2-C12 acrylate ester monomer; wherein the relative proportions of ethylenically unsaturated monomers are selected such that the following Equation I is satisfied: where a=2-3 b=weight percent hydrophobic aromatic high Tg monomer c=weight percent acrylic acid d=weight percent methacrylic acid, wherein the polymeric dispersion has a Tg of between-15° C. and 30° C., and wherein the paint composition has the following properties: (i) stain resistance of at least 3 as measured on a scale of 1-5 relative to an appropriate control sample comprising a paint class similar to that of said paint composition being measured using the scale, (ii) tint strength of at least 4 as measured on a scale of 1-5 where 1 is poor, being more than 20% low in tint strength, and, 5 is excellent, being less than 5% low in tint strength relative to a stored color reference having a defined and predetermined color, and (iii) viscosity stability of at least 3 as measured on a scale of 1-5 at a pH of between about 8.5 and about 9.5, where 1 is poor when the low shear viscosity increased by more than 100% and 5 is excellent when the low shear viscosity increased by less than 20%. 2. The water-borne domestic household paint composition of claim 1, wherein the hydrophobic aromatic ethylenically unsaturated monomer is in the range 8-70%. 3. The water-borne domestic household paint composition of claim 1, wherein the hydrophobic aromatic ethylenically unsaturated monomer is in the range 10-50%. 4. The water-borne domestic household paint composition of claim 1, wherein the hydrophobic aromatic ethylenically unsaturated monomer is styrene. 5. The water-borne domestic household paint composition of claim 1, wherein a in Equation I is in the range 2.5 to 10.0. 6. The water-borne domestic household paint composition of claim 1, wherein the Tg of the polymeric dispersion is-5 to 30° C. 7. The water-borne domestic household paint composition of claim 1, wherein the particle size of the polymeric dispersion is 200 nanometers (number average) maximum. 8. The water-borne domestic household paint composition of claim 1, wherein the particle size of the polymeric dispersion is 150 nanometers maximum. 9. The water-borne domestic household paint composition of claim 1, wherein the particle size of the polymeric dispersion is 120 nanometers maximum. 10. The water-borne domestic household paint composition of claim 1, wherein the weight majority of the carboxylic acid containing ethylenically unsaturated monomer is in favour of acrylic acid. 11. The water-borne domestic household paint composition of claim 1, wherein the carboxylic acid containing ethylenically unsaturated monomer is selected from acrylic acid and less than 4 wt % methacrylic acid, relative to the total monomers. 12. The water-borne domestic household paint composition of claim 1, wherein the carboxylic acid containing ethylenically unsaturated monomer is acrylic acid.