CAUSTIC CLEANING COMPOSITIONS
An aqueous caustic composition comprising: a caustic component; a surfactant; and an amino acid; wherein said composition has an advancing contact angle (θ A ) of less than 80 degrees and a receding contact angle (θ R ) of less than 20 degrees and processes associated therewith.
1 . An aqueous caustic composition comprising:
a caustic component;
a surfactant; and
an amino acid;
wherein said composition has an advancing contact angle (θ A ) of less than 80 degrees and a receding contact angle (θ R ) of less than 20 degrees.
2 . A composition according to claim 1 wherein said composition has a surface tension (SFT) when measured using a Wilhelmy plate with a tensiometer of less than 40 mN/m.
3 . A composition according to claim 1 wherein said composition has a surface tension (SFT) when measured using a Wilhelmy plate with a tensiometer ranging between 25 and 35 mN/m.
4 . A composition according to claim 1 wherein said caustic component is selected from the group consisting of: sodium hydroxide; potassium hydroxide; sodium metasilicate; and combinations thereof.
5 . The composition according to claim 1 wherein said caustic component is sodium hydroxide.
6 . The composition according to claim 1 wherein said amino acid is selected from the group consisting of basic amino acids.
7 . The composition according to claim 1 wherein said amino acid is selected from the group consisting of: lysine; histidine; arginine; hydrates and salts thereof and combinations thereof.
8 . The composition according to claim 1 wherein said amino acid is lysine Monohydrochloride Monohydrate.
9 . The composition according to claim 1 wherein said the surfactant comprises a Guerbet alcohol.
10 . The composition according to claim 1 wherein said surfactant comprises a Guerbet alcohol
11 . The composition according to claim 1 wherein said surfactant is selected from the group consisting of: Plurafac® LF 431; Lutensol® XL80; Lutensol® XP80; and combinations thereof.
12 . The composition according to claim 1 wherein said surfactant is Plurafac CS-10.
13 . The composition according to claim 1 wherein said caustic component is present in a concentration ranging from 30-60 wt. % of the total weight of the composition.
14 . The composition according to claim 1 wherein said caustic component is present at 60 wt % of the total weight of the composition.
15 . The composition according to claim 1 wherein said surfactant component is present in a concentration ranging from 2 to 20 wt % of the total weight of the composition.
16 . The composition according to claim 1 wherein said surfactant component is present in a concentration ranging from 2 to 10 wt % of the total weight of the composition.
17 . The composition according to claim 1 wherein said amino acid is present in a concentration ranging from 1 to 15 wt % of the total weight of the composition.
18 . The composition according to any claim 1 wherein said amino acid is present in a concentration ranging from 1 to 5 wt % of the total weight of the composition.
19 . A process for removing a residue from a substrate, comprising the steps of:
preparing a diluted cleaning solution, said diluted cleaning solution made by adding water to a concentrated cleaning solution so that the amount of caustic component contained in said diluted solution ranges from about 0.05% to about 5% by weight of said cleaning solution, said concentrated cleaning solution comprising:
a caustic component;
a surfactant; and
an amino acid; and
water
wherein said composition has an advancing contact angle (θ A ) of less than 80 degrees and a receding contact angle (θ R ) of less than 20 degrees.
applying said diluted cleaning solution to the substrate comprising the residue;
allowing a sufficient period of exposure of the cleaning solution to the substrate; and
removing said residue by rinsing with a fluid;
optionally, the rinsing step is repeated.
20 . The process according to claim 19 further comprising:
an acid cleaning step following the rinsing step and
second rinsing immediately after the acid cleaning step.
21 . The process according to claim 19 wherein said substrate is a metallic surface.
22 . An aqueous caustic composition comprising:
a caustic component;
a surfactant; and
an amino acid selected from the group consisting of: Lysine; Arginine; Histidine; Aspartic Acid; Glutamic Acid; Serine; Asparagine; Glutamine; Tyrosine; Methionine; Alanine; Valine; Cysteine; Proline; and Glycine;
wherein said composition is stable at temperatures of up to 45° C. for a period of up to 14 days.
23 . The aqueous caustic composition according to claim 22 where said amino acid is lysine.