Patent No. U.S. 7,851,545 B2
Chroma Australia Pty Limited has been granted a patent for a water-based artists’ paint composition consisting essentially of at least one pigment in an effective amount to provide the desired pigmentation; at least one alkali soluble polymer in an amount effective to increase the open time of the composition so that the paint composition remains workable and may be blended and altered for several hours and for as long as a day, the polymer being selected from polymers soluble at ambient temperature and pressure in an aqueous solution having a pH of from about 7 to 11; at least one substituted amine in an amount effective to adjust the pH to about 7 to 11, the amine selected from C1-6 alcohol amines, C1-6 alkyl C1-6 alcohol amines and mixtures thereof; a binding effective amount of at least one water dispersible acrylic polymer; and an effective amount of at least one alkali soluble or alkali swellable thickener.