Whitening agents for cellulosic substrates
This invention relates to novel whitening agents for cellulosic substrates. The whitening agents are comprised of at least two components: at least one chromophore component and at least one polymeric component. Suitable chromophore components generally fluoresce blue, red, violet, or purple color when exposed to ultraviolet light, or they may absorb light to reflect these same shades. The whitening agents are further characterized by having a dispersion component value of the Hansen Solubility Parameter of less than or equal to about 17 MPa 0.5 . This invention 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 laundry care composition comprising a laundry care ingredient and a whitening agent for cellulosic substrates, said whitening agent comprising:
(a) at least one chromophore component that comprises a thiophene colorant, and
(b) at least one polymeric component;
wherein the whitening agent is characterized by the following structure:
Wherein R 1 and R 2 can independently be selected from:
a) [(CH 2 CR′HO) x (CH 2 CR″HO) y H]
wherein R′ is selected from the group consisting of H, CH 3 , CH 2 O(CH 2 CH 2 O) z H;
wherein R″ is H; wherein x=0; wherein x+y≦5; wherein y≧1; and wherein z=0.
2. The laundry care composition of claim 1 , wherein the whitening agent possesses a dispersion component value of the Hansen Solubility Parameter of less than or equal to about 17 MPa 0.5 .
3. The laundry care composition of claim 2 , wherein the whitening agent possesses a dispersion component value of the Hansen Solubility Parameter from about 12 to about 17 MPa 0.5 .
4. The laundry care composition of claim 1 , wherein the whitening agent's chromophore exhibits an absorbance spectrum in water of from about 520 nanometers to about 640 nanometers.
5. The laundry care composition of claim 1 , wherein the whitening agent's chromophore exhibits an emission spectrum in water of from about 400 nanometers to about 480 nanometers.