ENHANCED MELTING POINT RINSE AID SOLIDS
The present invention is a method of preparing and using solid rinse aid compositions. The solid rinse aid composition generally includes a sulfate salt or sulfated surfactant, urea or polyethylene glycol as solidification agents and an effective amount of a surfactant wherein the composition is prepared by extruding. The surfactant may include at least one of an alcohol ethoxylate compound. The solid rinse aid composition may also incorporate a preservative system including sodium bisulfate. The solid rinse aid composition may be phosphate-free, aminocarboxylate-free, and GRAS if desired.
1 . A method of preparing a solid rinse aid composition comprising the steps of,
(a) preparing a composition, the composition comprising
(i) sulfate salts or sulfated surfactant or combinations thereof,
(ii) a hardening agent comprised of urea or polyethylene glycol,
(iii) less than 5 weight percent free water, and
(iv) surfactant; wherein a combined amount of sodium sulfate or sulfated surfactant and hardening agent is sufficient to solidify the composition; and
(b) extruding the composition.
2 . The method of claim 1 , wherein the combined amount of sodium sulfate or sulfated surfactant and hardening agent in the composition is in the range of 40 to 50 wt %.
3 . The method of claim 1 wherein the surfactant in the composition is comprised of two or more surfactants in addition to any sulfated surfactant.
4 . The method of claim 1 wherein the surfactant in the composition is comprised of at least one alcohol ethoxylate.
5 . The method of claim 1 wherein the composition is comprised of a sulfate salt and polyethylene glycol as the hardening agent.
6 . The method of claim 1 , wherein the composition further comprises at least one of a preservative, pH adjuster, or dye or any combination thereof.
7 . The method of claim 1 , wherein the composition comprises:
18-30 wt % sodium sulfate or sulfated surfactant;
18-30 wt % hardening agent;
up to 5 wt % water; and
up to 70 weight percent surfactant comprising one or more alcohol ethoxylates.
8 . The method of preparing the solid rinse aid composition of claim 1 wherein the composition additionally comprises:
bisulfate; and
one or more inorganic or organic acids;
wherein the total amount of bisulfate and one or more inorganic or organic acids is sufficient to provide a use solution having a pH less than 5.0 when the solid rinse aid composition is diluted at 10-500 parts of the solid rinse aid composition per million parts of aqueous diluent.
9 . The method of preparing the solid rinse aid composition of claim 1 wherein the composition is substantially free of phosphate and aminocarboxylate.
10 . The method of preparing the solid rinse aid composition of claim 1 wherein the melting point of the composition is in the range of 100 to 130° F.
11 . The method of preparing the solid rinse aid composition of claim 1 wherein the sulfated surfactant or sulfate salt is selected from the group consisting of sodium ethyl hexyl sulfate, sodium linear octyl sulfate, sodium lauryl sulfate, and sodium sulfate.
12 . The method of preparing the solid rinse aid composition of claim 1 wherein the hardening agent is comprised of polyethylene glycol having a molecular weight of 4,000 or less.
13 . A method for rinsing a substrate surface, the method comprising the steps of:
(a) preparing a solid rinse aid composition, comprising:
(i) sulfate salt or a sulfated surfactant, or a combination thereof;
(ii) a hardening agent consisting of urea or polyethylene glycol with a molecular weight of at least 2000 or a combination thereof, wherein a combined amount of sulfate and hardening agent is sufficient for solidification of the rinse aid composition;
(iii) up to 5 weight percent water; and
(iv) surfactant;
(b) extruding the composition;
(c) diluting the solid rinse aid composition with an aqueous diluent to provide a use solution, the use solution having a pH of less than 7.0 and greater than 5.0; and
(d) applying the aqueous use solution to the substrate surface.
14 . The method of claim 13 wherein the combined amount of sulfate salt or sulfated surfactant and hardening agent in the composition is in the range of 40 to 50 wt %.
15 . The method of claim 13 wherein the surfactant in the composition is comprised of at least one alcohol ethoxylate
16 . The method of rinsing a solid substrate of claim 13 wherein the composition additionally comprises:
bisulfate; and
one or more inorganic or organic acids;
wherein the total amount of bisulfate and one or more inorganic or organic acids is sufficient to provide a use solution having a pH less than 5.0 when the solid rinse aid composition is diluted at 10-500 parts of the solid rinse aid composition per million parts of aqueous diluent.
17 . The method of rinsing a solid substrate of claim 13 wherein the composition is substantially free of phosphate and aminocarboxylate.
18 . The method of rinsing a solid substrate of claim 13 wherein the rinse aid composition has a melting point of the composition is in the range of 100 to 130° F.
19 . A method of increasing the melting point of solid rinse aid or solid detergent composition, comprising the steps of:
(a) providing a composition comprising:
(i) at least 24 weight percent of a hardening agent comprised of polyethylene glycol having a molecular weight of at least 2000 or urea,
(ii) at least 18 weight percent of a sulfate salt or a sulfated surfactant, or a combination thereof,
(iii) at least 25 weight percent of a surfactant in addition to any sulfated surfactant, if any,
(iv) less than 5 weight percent free water; and
(b) extruding the solid composition.
20 . The method of claim 19 wherein the combined amount of sodium sulfate or sulfated surfactant and hardening agent in the composition is in the range of 42 to 52 wt %.