Whitening agents for cellulosic substrates
The present application relates to novel whitening agents for cellulosic substrates. The whitening agents are comprised of at least two constituents: at least one chromophore constituent and at least one polymeric constituent. Suitable chromophore components generally fluoresce blue, red, violet, or purple color when exposed to light, or they may absorb light to reflect these same shades. The whitening agents are further characterized by the polymeric component comprising at least two repeating glycerol units. This disclosure also relates to laundry care compositions including but not limited to liquid and/or powder laundry detergent formulations and rinse added fabric softening (RAFS) compositions that comprise such whitening agents.
1. A whitening agent consisting of a nonionic amphiphilic nitrogen-linked polyglycerol having the structure of Formula I:
wherein each R 5 is independently selected from the group consisting of alkyl, oxyalkyl, oxyaryl, sulfonamidoalkyl, sulfonamidoaryl, amidoalkyl, amidodialkyl, amidoaryl, amidodiaryl, halogen, thioalkyl and thioaryl;
wherein the index a is an integer from about 0 to about 4;
wherein D is an aromatic or heteroaromatic group;
wherein R 1 is selected from the group consisting of H, alkyl, aryl, aryl alkyl and [(CH 2 CH 2 O) x (CH 2 C(OR)HCH 2 O) y (CH 2 CH 2 O) z H], wherein R 2 is [(CH 2 CH 2 O) x (CH 2 C(OR)HCH 2 O) y (CH 2 CH 2 O) z H], wherein each R is independently selected from the group consisting of H, (CH 2 CH 2 O) z′ H, and mixtures thereof; wherein groups indicated by indices x, y and z may be arranged in any order; wherein x=0, wherein 1≤y≤5 and at least one y≥2; and wherein independently each z=0 and each z′=0.
2. A whitening agent according to claim 1 , wherein said nonionic amphiphilic nitrogen-linked polyglycerol dye is an azo dye having the structure of Formula II:
wherein the index a is from 0 to 2; wherein each R is independently selected from the group consisting of H, (CH 2 CH 2 O) z′ H, and mixtures thereof; wherein groups indicated by indices x, y and z may be arranged in any order; wherein x=0, wherein 1≤y≤5 and at least one y≥2; and wherein independently each z=0 and each z′=0.