CA3179607A1

CA3179607A1 - Nano-cleaners for metalworking uses

Info

Publication number: CA3179607A1
Application number: CA3179607A
Authority: CA
Inventors: Markus Weissenberger; Elsayed Abdelfatah
Original assignee: Dorf Ketal Chemicals FZE
Current assignee: Dorf Ketal Chemicals FZE
Priority date: 2022-10-21
Filing date: 2022-10-21
Publication date: 2024-04-21

Abstract

A chelating agent-free composition for use in metalworking cleaning, wherein said composition comprises:
- water;
- a caustic component;
- a solvent;
- an anionic surfactant;
- a nonionic surfactant;
- optionally, a corrosion inhibitor;
- a fatty alcohol polyglycol ether; and - a hydrophobic component.

Description

NANO-CLEANERS FOR METALWORKING USES
FIELD OF THE INVENTION
This present invention relates to compositions useful for cleaning metal surfaces, more specifically, the invention relates to emulsion-containing compositions which, in addition to cleaning the surface of metals when applied thereto, also have other desirable properties which make them highly useful for industrial metal-working applications.
BACKGROUND OF THE INVENTION
Metalworking Fluids (MWFs) is the name given to various oil or water-based fluids which are used to cool and/or lubricate metal workpieces when they are being machined, ground, milled, etc. These fluids have a range of application which include: reducing the heat and friction between the cutting tool and the workpiece, and preventing burning and smoking during machining of metal parts.
The need to clean the surface of metals subsequent to various metal working operations is well known. Using metalworking fluids also helps improve the machining of workpieces by helping in removing the fines and chips from the tool being used and the surface of the workpiece.
While there are many different components and additives in metalworking fluids, there are four basic classes as follows: straight oils; soluble oils (emulsifiable oils);
semi-synthetic fluids; and synthetic fluids. Straight oils are also referred to as "cutting" or "neat"
oils. They are mainly composed of mineral (petroleum), animal, marine, vegetable or synthetic oils. These oils are not diluted with water but other additives may be present. Soluble oils also referred to as emulsifiable oils contain generally between 30 to 85 percent of refined petroleum oils along with other additives such as emulsifiers to disperse the oil in water. Semi-synthetic fluids contain between 5 to 30 percent of severely refined petroleum oils, 30 to 50 percent water and a number of additives. Synthetic fluids do not contain petroleum oils but comprise water and many other additives to help in lubricating the metals exposed thereto.
Metalworking fluids, irrespective of which class they belong to, may contain one or more of a variety of additives, including, but not limited to: sulfiffized or chlorinated compounds; corrosion inhibitors;
anti-mist agents; anti-weld agents; emulsifiers; alkanolamines; biocides;
preservatives; stabilizers;
dispersants; defoamer; colourants; dyes; odourants; and fragrances.
A concern when using metalworking fluids is the propensity to have contaminants present in the fluid. Said contaminants can result in growth of bacteria and fungi in said fluid. The impact of the bacteria Date Regue/Date Received 2022-10-21 in a metalworking fluid is non-negligible as it leads a degradation of the emulsion and thus a complete breakdown of the fluid's properties. To overcome the presence and growth of bacteria in those fluids, biocides are routinely used, however, biocide products do present hazards themselves. 'Tramp oil' is another possible contaminant in MWFs. It is an oil used to lubricate machines, such as hydraulic oil, gear box oil, and other lubricants. Tramp oils can provide a source of nutrients for bacteria, and thus their presence in MWFs is undesirable. Other MWFs contaminant include metals pieces, water and polyaromatic hydrocarbon.
MWFs have been associated with several health concerns including but not limited to, contact dermatitis, asthma and lung irritation (by breathing the mist), chronic bronchitis, and impaired lung function. In the past, some chemicals found in certain MWF formulations have been linked to increased risk of certain cancers such as larynx, rectum, pancreas, skin, scrotum, and bladder. However, because of the lapse of time between exposure and the appearance of symptoms or development of the disease can be up to sat least 1 or two decades, most of the cancer cases associated with the use of MWFs are the result of exposure which took place in the 1970s or even before then. Nowadays, the risk of developing cancer from exposure to MWF is not as clear but discounting the possible risk should be avoided.
Health risks resulting from exposure to MWF are not negligible. Aside from cancer, the main concern relates to skin and lungs.
It is known that all categories of MWFs can lead to the development of skin irritation of varying degree. Irritant or allergic contact dermatitis has been reported to occur from exposure to soluble, semisynthetic, and synthetic MWFs. Dermatitis can be caused by one or more of a variety of the additives used in MWF, including: biocides; rust control chemicals; corrosion inhibitors; as well as contaminants from metals (nickel, cobalt and chromium).
Other drawbacks of the use of MWFs include respiratory health dangers. Some of the respiratory issues related to exposure to MWFs include: work-related asthma, bronchitis, irritation of the respiratory tract and breathing difficulties. These can come about through exposure to mist, aerosol, and/or vapours of MWFs containing various chemicals and additives.
U.S. Pat. No. 4,421,680 teaches cleaning and degreasing compositions containing potassium hydroxide and sodium metasilicate pentahydrate in combination with n-butoxyethanol, coconut diethanolamide, cocamidopropyl betaine, isopropylamine salt of dodecylbenzenesulfonic acid (DDBSA)

2 Date Regue/Date Received 2022-10-21 and water.
US patent no. 6,420,323 B2 teaches a low-foam emulsifier system is presented containing (a) an ethoxylate/propoxylate of one or more C8-C18 fatty alcohols, where the ethoxylate/propoxylate contains 2 to 6 ethylene oxide units and 4 to 8 propylene oxide units, with (b) a fatty alcohol propoxy late or distillation residue of fatty alcohol or fatty alcohol propoxylate, where the fatty alcohol contains 12 to 24 carbon atoms and up to three propylene oxide units. The weight ratio of (a) to (b) is from 1:0.3 to 0.3:1. The emulsifier system produces a low amount of foam, and is useful in industrial metal processing applications such as cleaning, corrosion protection or cooling lubricant emulsions.
US patent no. 6,524,396 B1 teaches a process for metal cutting using a water-mixed cutting compound and subsequent cleansing and corrosion protective treatment wherein an oil in water emulsion is used as a cutting compound which contains; (i) an amount emulsifier system consisting of: (a) ethoxylates/propoxylates of fatty alcohols having 8 to 18 carbon atoms in the alcohol, which contains 2 to 6 ethylene oxide units and 4 to 8 propylene oxide units; (b) fatty alcohols and/or fatty alcohols propoxylates having 12 to 24 carbon atoms in the alcohol and 0 to 3 propylene oxide units and/or distillation residues of such fatty alcohols; in a ratio by weight, a:b=1:0.2 to 0.2:1; and (ii) corrosion inhibitory; and an aqueous solution or suspension is used for cleansing an anti-corrosion treatment which contains the same emulsifier system and the corrosion inhibitors as the cutting compound. The cutting compound and the cleansing and corrosion protective treatment material comprise a system for treating the metal during cutting and cleansing.
US patent no. 5,284,591A discloses a multipurpose functional fluid is disclosed which is comprised of a major amount of a hydrocarbon oil and a minor amount, sufficient to improve characteristics of the fluid of a novel additive. The additive is comprised of a calcium salt complex, a group II metal dithiophosphate salt, a borated epoxide, a carboxylic solubilizer and a sulfurized composition. The calcium salt is preferably in the form of an overbased calcium sulfonate salt, the antiwear agent is preferably in the form of a zinc dithiophosphate salt, the borated epoxide is preferably the reaction product of boric acid and a 16 carbon 1,2 epoxide, the carboxylic solubilizer is preferably in the form of a reaction product of an acylating agent containing a substituted hydrocarbyl-based substituent containing about 12 to 500 carbon atoms; and the sulfurized composition is in the form of a co-sulfurized mixture of 2 or more reactants selected from the group consisting of at least one fatty acid ester of a polyhydric alcohol, at least one olefin and at least one fatty acid. Other components such as viscosity improvers and antifoaming agent are generally present in the fluid.

3 Date Regue/Date Received 2022-10-21 US patent no. 4,675,125A teaches improved multi-purpose metal cleaning compositions are provided comprised of 5 to 40 parts by weight ethoxylated aliphatic alcohol or ethoxylated alkylphenol, 4 to 20 parts by weight alkanolamine salt of a fatty acid, 2 to 15 parts by weight boramide, 2 to 15 parts by weight alcohol, glycol or ether glycol, 0.05 to 2.5 parts by weight antifoam agent, and 5 to 98 parts by weight water. In addition to being highly effective cleaners for the removal of grease, oil, dirt, scale and metal fines, the compositions of this invention also provide a non-sticky and non-greasy corrosion-resistant protective barrier on the surface of the metal.
US patent number 5,688,755A teaches a multi-purpose metal cleaning composition comprising: (a) to 40 parts by weight ethoxylated aliphatic alcohol or ethoxylated alkylphenol; (b) 4 to 20 parts by weight alkanolamine salt of a fatty acid; (c) 2 to 15 parts by weight boramide obtained by the reaction of boric acid or its analogs with a molar excess of alkanolamine selected from the group consisting of diethanolamine, diisopropanolamine and triethanolamine at a temperature of about 130 C. or above; (d) 2 to 15 parts by weight alcohol, glycol or ether glycol; (e) 0.05 to 2.5 parts by weight antifoam agent; and (f) 5 to 98 parts by weight water.
Other cleaning compositions used in the metal working industry comprise chelating agents, sulfonate compounds and benzesulfonic acids. These compounds carry a number of health warnings, including but not limited to, acute toxicity, eye damage if exposed thereto, aquatic toxicity, etc.
In light of the state of the art, there still exists a need for a metal;
working fluid composition which overcomes at least some of the drawbacks of the known composition. It would be highly advantageous if other aqueous compositions having moderate pH and which are effective cleaners for metal surfaces were available. It would be even more advantageous if the cleaners also provided a non-greasy and non-sticky protective barrier on the surface of the metal to prevent rust and corrosion during storage and shipping.
These and other advantages are realized with the metal cleaning compositions of the present invention.
SUMMARY OF THE INVENTION
In accordance with a first aspect of the present invention, there is provided a chelating agent-free composition for use in metalworking cleaning, wherein said composition comprises:
- water;
- a caustic component;
- a solvent;

4 Date Regue/Date Received 2022-10-21 - an anionic surfactant;
- a nonionic surfactant;
- optionally, a corrosion inhibitor;
- a fatty alcohol polyglycol ether; and - a hydrophobic component.
According to a preferred embodiment of the present invention, the solvent is selected from the group consisting of: methanol; ethanol; isopropanol, 1-propanol; and glycol ether. Preferably, the solvent is present in an amount ranging from 5 to 15 wt % of the total weight of the composition.
According to a preferred embodiment of the present invention, the anionic surfactant comprises an alkyldiphenyloxide disulfonate. Preferably, the alkyldiphenyloxide disulfonate is Dowfax C 10L.
Preferably, anionic surfactant is present in an amount ranging from 5 to 15 wt % of the total weight of the composition.
According to a preferred embodiment of the present invention, the fatty alcohol polyglycol ether, is Emuldac 251 PE. Preferably, the fatty alcohol polyglycol ether is present in an amount ranging from 1 to 5 wt % of the total weight of the composition.
According to a preferred embodiment of the present invention, where the nonionic surfactant is an ethoxylated alcohol. Preferably, the nonionic surfactant is Novel 23E3.
Preferably, the nonionic surfactant is present in an amount ranging from 5 to 20 wt % of the total weight of the composition.
According to a preferred embodiment of the present invention, the hydrophobic component is a naphthenic mineral oil. Preferably, the hydrophobic component is pale oil 40.
Preferably, the hydrophobic component is present in an amount ranging from 2 to 5 wt % of the total weight of the composition.
According to a preferred embodiment of the present invention, the caustic component is selected from the group consisting of: potassium hydroxide or a modified caustic soda.
Preferably, the caustic component is present in an amount ranging from 0.01 to 0.5 wt % of the total weight of the composition.
Preferably, the corrosion inhibitor is present in an amount ranging from 0.5 to 5 wt % of the total weight of the composition.
Date Regue/Date Received 2022-10-21 According to a preferred embodiment of the present invention, the pH of the composition ranges from 7 to 13. Preferably, the pH of the composition ranges from 8 to 12.
According to a preferred embodiment of the present invention, the metal cleaning composition comprises ingredients which are readily compatible and when combined in the proportions indicated provide a cleaner concentrate which can be used as such or further diluted with water. The aqueous cleaner compositions of this invention are highly effective cleaners for the removal of residual oil, dirt, scale, metal fines from metal surfaces. They further provide good rust resistance as well as good metal corrosion-resistance.
BRIEF DESCRIPTION OF THE FIGURES
Features and advantages of embodiments of the present application will become apparent from the following detailed description and the appended figures, in which:
Figure 1 is a picture of bolts covered in grime before and after cleaning with a composition according to a preferred embodiment of the present invention;
Figure 2 is picture of various greased metallic coupons before and after cleaning with a composition according to a preferred embodiment of the present invention;
Figures 3a and 3b are pictures of the surface of Test A: AL5083 metallic coupon after being exposed to a composition according to a preferred embodiment of the present invention for 6 hrs at 68 F
(20 C) at 10X magnification (left) and 40X magnification (right).
Figures 4a and 4b are pictures of the surface of Test B: AL7075 metallic coupon after being exposed to a composition according to a preferred embodiment of the present invention for 6 hrs at 68 F
(20 C) at 10X magnification (Figure 4a) and 40X magnification (Figure 4b).
Figures 5a and 5b are pictures of the surface of Test C: ABS metallic coupon after being exposed to a composition according to a preferred embodiment of the present invention for 6 hrs at 68 F (20 C) at 10X magnification (left) and 40X magnification (right).
DETAILED DESCRIPTION OF THE INVENTION

Date Regue/Date Received 2022-10-21 According to a preferred embodiment of the present invention, the metal cleaning composition can comprise a combination of surfactants which are environmentally friendly and when formulated as part of an emulsion can be highly effective at removing various hydrophobic contaminants. Preferably, the composition is an effective cleaner for metalworking equipment which can minimize the overall dosage of chemical cleaners required compared to conventional compositions. Moreover, in a preferred embodiment, the composition can be useful for various applications and thus be considered a multi-purpose cleaning composition.
Most cleaners are diluted with tap water and hence required a chelating agent to ensure hard water stability. The most common chelator is EDTA which is resistant to bacterial biodegradation. Hence, it is desirable to have a hard-water stable high-performance cleaner which does not contain any chelating agent.
According to a preferred embodiment of the present invention, the metal cleaning composition comprises a microemulsion which is hard-water stable without any chelating agent. Preferably, a minimum concentration of the oil phase is present.
The composition according to a preferred embodiment of the present invention, is novel as it is a microemulsion. The oil phase, unlike the prior art, allows to encapsulate the surfactants into micellar structures which allow the composition to be stable in hard water without the need for a chelating agent.
According to a preferred embodiment of the present invention, the metal cleaning composition is an alkaline metal cleaning composition. Preferably, it is a highly concentrated, alkaline cleaner that can be used to clean and degrease a wide variety of soils in many different applications.
According to a preferred embodiment of the present invention, the alkaline metal cleaning composition is a microemulsion-based cleaning composition that encapsulates a blend of eco-friendly surfactants to improve penetration and emulsification of soils for efficient removal from surfaces.
According to a preferred embodiment of the present invention, the metal cleaning composition provides at least one of the following advantages:
- a highly concentrated formula;
- encapsulation of surfactants improves penetration and emulsification for efficient removal of soils;
- improved break down of fats, oil and greases over neutral cleaners;

Date Regue/Date Received 2022-10-21 - capable of removing grease, viscous oils, fats, grime, cutting and foaming oils, rust preventative films, oxidized and sticky deposits.
According to a preferred embodiment of the present invention, the metal cleaning composition can be used in any one of the following applications:
- heavy duty and light duty cleaning and degreasing;
- hard surface cleaning;
- concrete surface preparation; and - parts washers, dip tanks and pressure washing.
According to a preferred embodiment of the present invention, the metal cleaning composition can comprise a combination of surfactants which are environmentally friendly and when formulated as part of an emulsion can be highly effective at removing various hydrophobic contaminants.
Example 1 Table 1 provides a summary of the composition of Example 1 which is a formulation according to a preferred embodiment of the present invention where the pH of said formulation is alkaline. Table 2 provides a summary of various relevant physicochemical characteristics of the composition of Example 1.
Table 1: Composition of an alkaline metal washing formulation (Example #1) according to a preferred embodiment of the present invention Component wt% g Water 57.33 57.33 KOH, 45% 0.175 0.175 Ethanol 10 10 Dowfax ClOL 10 10 Novel 23E3 15 15 CIX-2 (Corrosion Inhibitor) 2 2 Emuldac 251PE 2 2 Pale Oil 40 3.5 3.50 Total 100 100 %active 42.7 Table 2: Physicochemical Characteristics of the composition set out in Example 1 Sample #1 Sample #2 pH 11.5 11.52 Date Regue/Date Received 2022-10-21 RI 1.3774 1.3775 SG 0.985 0.985 Density 0.9830 0.9833 Appearance Liquid Liquid Smell Characteristic Chamcteristic Color Yellow Yellow Example 2 Table 3 provides a summary of the composition of Example 2 which is a formulation according to a preferred embodiment of the present invention where the pH of said formulation is neutral. Table 4 provides a summary of various relevant physicochemical characteristics of the composition of Example 2.
Emuldac 251 PE is a fatty alcohol polyglycol ether, based on Nafol 16 18, propylene oxide and ethylene oxide. It is a surfactant having a low hydrophilic-lipophilic ratio.
It is often used as antifoam agent in papermaking. It has a cloud point of 2I-26 C, a pH (5%) level of 4.0-6.0, and a free water content of <
0.5% wt.
Dowfax C IOL is an anionic surfactant which comprises an alkyldiphenyloxide disulfonate. It rinses easily from surfaces, and is readily soluble in acidic, alkaline, bleach & other oxidizing systems. It is also stable in hard water.
Nover23E3 ethoxylate is a biodegradable, nonionic surfactant derived from SAFOL 23 alcohol and ethoxylated to an average of 3 moles of ethylene oxide. It is essentially 100% active unless diluted with water. It is a slightly hazy liquid that is readily soluble in water.
Some of its applications include, as an emulsifier in personal care products, also it is a foaming agent. It is referred to as an C10-16 ethoxylated alcohol and its CAS Number is 68002-97-1. Chemical SAFOL 23 Alcohol is a blend of C12 and C13 branched and linear alcohols. The branched isomers in SAFOL 23 Alcohol are unique in that the branch is located mid-chain. This leaves the primary alcohol unobstructed for further derivatization. SAFOL 23 Alcohol is a synthetic alcohol produced from olefins obtained using the novel Fischer-Tropsch process.
Triton hand sanitizer (THS) is a hand sanitizer comprising mainly of ethanol (over 70 wt%) and a few other constituents. According to a preferred embodiment of the present invention, the source of ethanol is from expired hand sanitizer compositions being high in ethanolic content, for example above 60%, more preferably above 70% even more preferably above 75% and yet even more preferably above 80% ethanol content. The composition used in testing is a hand sanitizer comprising: 77.3 wt% ethanol; 20.1 wt% water;
2.1 wt% glycerol; and 0.5 wt% H202.

Date Regue/Date Received 2022-10-21 Pale oil is characterized as a straight naphthenic mineral oil. It is straw or pale yellow in color. It is typically used as a once-through lubricant and in the formulation of process oils. The naphthenic oils are available in a wide range of viscosities. Pale oil 40, Pale oil 60, Pale oil 100 and Light Pale oil are types of naphtenic oils obtained from the same processing approach. Pale oil 40 is a petroleum distillate, hydrotreated heavy naphthenic, its CAS number is 64742-52-5. According to a preferred embodiment of the present invention, the composition comprises Pale oil 40.
According to a preferred embodiment of the present invention, the composition comprises a corrosion inhibitor. Preferably, the corrosion inhibitor is a composition (CD(-2) comprising: citral at 8.8 wt%; Basocorr 2005 at 40.6 wt %; and butyl carbitol at 50.6 wt.%).
According to a preferred embodiment of the present invention, the water used may be pure water, ion exchange water, soft water, distilled water, and tap water. These may be used alone or in combination of two or more. Of these, tap water and ion-exchanged water are preferably used from the viewpoints of economy and storage stability. "Water" is the sum of water contained in the form of crystal water or aqueous solution derived from each component constituting the cleaning composition of the present invention and water added from the outside, and the entire composition when water is added is 100%.
According to a preferred embodiment of the present invention, the modified caustic soda, also interchangeably referred to as caustic component, is selected from the group consisting of: potassium hydroxide; sodium hydroxide; lithium hydroxide; cesium hydroxide; rubidium hydroxide and combinations thereof; and a modified caustic composition comprises one of the above mentioned caustic component (potassium hydroxide; sodium hydroxide; lithium hydroxide; cesium hydroxide;
rubidium hydroxide) in combination with a causticity modifying additive, wherein said causticity modifying additive can provide an extended (more methodical and linear) buffering effect to the caustic composition as well as greatly lowering the freeze point and providing an increased level of dermal protection. Examples of such modified caustic composition can be found in Canadian patent applications CA 3,023,705;
CA 3,023,613; CA
3,023,610; and CA 3,023,604.
According to a preferred embodiment of the present invention, the modified caustic composition comprises:
Date Regue/Date Received 2022-10-21 - a caustic component selected from the group consisting of: potassium hydroxide;
sodium hydroxide; lithium hydroxide; cesium hydroxide; rubidium hydroxide and combinations thereof;
and - a causticity modifying additive selected from the group consisting of:
taurine; gamma-aminobutyric acid; aminovaleric acid; aminocaproic acid; aminocapric acid;
sulfopyruvic acid;
sulfobutanoic acid; sulfopentanoic acid; sulfohexanoic acid; phosphonium zwitterions with either a sulfonic acid or carboxylic acid group selected from the group consisting of: 2-hydroxyethyl triphenylphosphonium sulfate zwitterion; (Z- hydroxyethyptrimethylphosphonium sulfate zwitterion (M.W. of 200.2); (3- hydroxy-n- propyl)triphenylphosphonium sulfate zwitterion (M.W.
of 400.4); (2-hydroxy-1- methyl-n- propyl) trimethylphosphonium sulfate zwitterion (M.W. of 228.3); (3-hydroxy-n- propy Dtri-n- butylphosphonium sulfate zwitterion (M.W.
of 340.5); (Z -hydroxy-1,2- diphenylethyl)- triethylphosphonium sulfate zwitterion (M.W. of 394.5); (3-hydroxy-n- propyl)dimethylphenylphosphonium sulfate zwitterion (M.W. of 276.3); (Z-hydroxy-n-butyl)triisopropylphosphonium sulfate zwitterion (M.W. of 312.4); (3 -hydroxy -1- methyl- n-buty1)-n-butyl-di-n-propylphosphonium sulfate zwitterion (M.W. of 340.5); and (3-hydroxy- 2-ethyl- 4 methyl-n-penty1)-n-butyldiphenylphosphonium sulfate zwitterion (M.W.
of 450.6); -phophoric acid ester group with an amine group; and phosphonic and phosphinic acids and their esters with an amine group.
According to a preferred embodiment of the present invention, the caustic component is selected from the group consisting of: potassium hydroxide; sodium hydroxide; and combinations thereof.
Preferably, the caustic component is sodium hydroxide. Preferably, the caustic component is present in a concentration of up to 40 wt % of the modified caustic composition. Also preferably, the caustic component is present in a concentration ranging from 5 to 40 wt % of the modified caustic composition. More preferably, the caustic component is present in a concentration ranging from 10 to 30 wt % of the modified caustic composition. Most preferably, the caustic component is present in a concentration ranging from 15 to 25 wt % of the modified caustic composition. According to a preferred embodiment of the present invention, the caustic component is present in a concentration of 25 wt % of the modified caustic composition. According to a preferred embodiment of the present invention, the causticity modifying additive is present in a concentration ranging from 4 wt% to 25 wt % of the composition. Preferably, the causticity modifying additive is present in a concentration ranging from 5 wt%
to 15 wt % of the composition. More preferably, the causticity modifying additive is present in a concentration ranging from wt% to 10 wt % of the composition.

Date Regue/Date Received 2022-10-21 According to another preferred embodiment of the present invention, the modified caustic composition comprises:
- a caustic component selected from the group consisting of: potassium hydroxide; sodium hydroxide; lithium hydroxide; cesium hydroxide; rubidium hydroxide and combinations thereof;
and - a causticity modifying additive selected from the group consisting of:
monoethanolamine;
diethanolamine; triethanolamine; aminomethyl propanol; propanolamine;
dimethylethanolamine;
and N- methylethanolamine. Preferably, the additive is monoethanolamine.
According to a preferred embodiment of the present invention, the caustic component is selected from the group consisting of: potassium hydroxide; sodium hydroxide; and combinations thereof.
Preferably, the caustic component is sodium hydroxide. Preferably, the caustic component is present in a concentration of up to 40 wt % of the modified caustic composition. Also preferably, the caustic component is present in a concentration ranging from 5 to 40 wt % of the modified caustic composition. More preferably, the caustic component is present in a concentration ranging from 10 to 30 wt % of the modified caustic composition. Most preferably, the caustic component is present in a concentration ranging from 15 to 25 wt % of the modified caustic composition. According to a preferred embodiment of the present invention, the caustic component is present in a concentration of 25 wt % of the modified caustic composition. According to a preferred embodiment of the present invention, the causticity modifying additive is present in a concentration ranging from 4 wt% to 25 wt % of the composition. Preferably, the causticity modifying additive is present in a concentration ranging from 5 wt%
to 15 wt % of the composition. More preferably, the causticity modifying additive is present in a concentration ranging from wt% to 10 wt % of the composition.
According to yet another preferred embodiment of the present invention, the modified caustic composition comprises:
- a caustic component selected from the group consisting of: potassium hydroxide; sodium hydroxide; lithium hydroxide; cesium hydroxide; rubidium hydroxide and combinations thereof;
and - a causticity modifying additive which is glycine.
According to a preferred embodiment of the present invention, the caustic component is selected from the group consisting of: potassium hydroxide; sodium hydroxide; and combinations thereof.
Preferably, the caustic component is sodium hydroxide. Preferably, the caustic component is present in a Date Regue/Date Received 2022-10-21 concentration of up to 40 wt % of the modified caustic composition. Also preferably, the caustic component is present in a concentration ranging from 5 to 40 wt % of the modified caustic composition. More preferably, the caustic component is present in a concentration ranging from 10 to 30 wt % of the modified caustic composition. Most preferably, the caustic component is present in a concentration ranging from 15 to 25 wt % of the modified caustic composition. According to a preferred embodiment of the present invention, the caustic component is present in a concentration of 25 wt % of the modified caustic composition. According to a preferred embodiment of the present invention, the causticity modifying additive is present in a concentration ranging from 4 wt% to 25 wt % of the composition. Preferably, the causticity modifying additive is present in a concentration ranging from 5 wt%
to 15 wt % of the composition. More preferably, the causticity modifying additive is present in a concentration ranging from wt% to 10 wt % of the composition.
According to yet another preferred embodiment of the present invention, the modified caustic composition comprises:
- a caustic component selected from the group consisting of: potassium hydroxide; sodium hydroxide; lithium hydroxide; cesium hydroxide; rubidium hydroxide and combinations thereof;
and - a causticity modifying additive selected from the group consisting of:
lysine monohydrochloride;
threonine; methionine; glutamic acid; and taurine. Preferably, the causticity modifying additive is lysine monohydrochloride or taurine. More preferably, the causticity modifying additive is lysine monohydrochloride.
According to a preferred embodiment of the present invention, the caustic component is selected from the group consisting of: potassium hydroxide; sodium hydroxide; and combinations thereof.
Preferably, the caustic component is sodium hydroxide. Preferably, the caustic component is present in a concentration of up to 40 wt % of the modified caustic composition. Also preferably, the caustic component is present in a concentration ranging from 5 to 40 wt % of the modified caustic composition. More preferably, the caustic component is present in a concentration ranging from 10 to 30 wt % of the modified caustic composition. Most preferably, the caustic component is present in a concentration ranging from 15 to 25 wt % of the modified caustic composition. According to a preferred embodiment of the present invention, the caustic component is present in a concentration of 25 wt % of the modified caustic composition. According to a preferred embodiment of the present invention, the causticity modifying additive is present in a concentration ranging from 4 wt% to 25 wt % of the composition. Preferably, the causticity modifying additive is present in a concentration ranging from 5 wt%
to 15 wt % of the Date Regue/Date Received 2022-10-21 composition. More preferably, the causticity modifying additive is present in a concentration ranging from wt% to 10 wt % of the composition.
According to a preferred embodiment of the present invention, the high foaming caustic cleaning composition with polymer for removing and suspending particulates from ship holds comprises a modified caustic composition, comprising lysine, NaOH and water to ensure dermal safety. According to a preferred embodiment of the present invention, the modified caustic soda used in the composition comprises 25%
NaOH, 4% Lysine and 71 % water.
Parts Cleaning In a first test, grimy screws were placed in the composition of Example #1 (diluted to 1% in water) for 15 minutes then dried with a paper towel (Figure 1).
Figure 2 shows several greased coupons before and after cleaning with according to a preferred embodiment of the present invention. Used metal coupons were placed in 1% of the composition of Example #1 (in tap water) for 15 minutes. Then the coupons were placed in crude oil (Spearfish formation) for 15 minutes. The oily coupons were then placed into the composition of Example #1 again (15 min) to remove the oil. The same procedure was repeated but the oily coupons blotted before placing them into the composition of Example #1. Before and after pictures were taken as shown below. Used coupons were used so the oil can stick to the rougher corrosion surface. The metallic coupons used included: P110, 316, J55, L80, C1018 and F12801. As can be clearly seen in the "after" images, the oil film was removed completely. The performance of the composition tested in cleaning several metal parts that were heavily contaminated with oil showed that it did, in each instance, clean them very effectively.
Corrosion Testing Procedure:
Corrosion tests were performed in glass jars at ambient conditions on various metals. The summary of the corrosion test is set out in Table 5. Before testing each coupon was cleaned with DI water and acetone and airdried. The coupons were weighed on a 4-digit analytical balance and placed in ajar. Test fluid was added until the coupon was completely submerged. After the exposure period, the coupon was removed, washed with water, followed by an acetone wash, air dried, and then weighed.
The corrosion rate was determined from the weight loss, and the pitting index (Table 7) was evaluated visually at 40X
magnification, and a photo of the coupon surface at 10X and 40X magnification was taken.

Date Regue/Date Received 2022-10-21 Table 5: Corrosion test conditions Temperature Duration Test Test Fluid Coupon Tested (oF) ( c) (hrs) A composition of Example 141 AL5083 68 20 6 composition of Example 141 AL7075 68 20 6 composition of Example 141 ABS 68 20 6 Results:
The corrosion test results are shown in Table 6 and in Figures 3, 4, and 5.
There is no observable corrosion or pitting on any of the three coupons tested. This confirms that the compositions according to a preferred embodiment of the present invention is effective and compatible with a wide variety of metals.
Table 7 provides a literature reference for pitting which is referred to in the testing reported herein.
Table 6: Coupon corrosion test results of experiments carried out at 20 C
(68 F) Corrosion Rate Pitting Test Test Fluid Coupon Tested (mm/year) (lb/ft 2) Index A composition of Example 141 AL5083 0 0 0 composition of Example 141 AL7075 0 0 0 composition of Example 141 ABS 0 0 0 Table 7: Pitting Index Rating Scale (from FinSgar, M.; Jackson, J. Corrosion Science, 2014, 86, 17-41) Description of Pitting Pitting Index No pits. The surface is the same as for the original untreated coupon Intergranular corrosion on the cut edge of the coupon, giving a sintered effect; no pits on major surfaces Small, shallow pits on cut edges: no pits on major surfaces 2 Scattered, very shallow pinpoint pits, less than 25 pits on either surface ¨
i.e.

on front or back More than 25 pits of Pitting Index 3 on either surface 4 Ten or fewer pits, 1/32" to 1/16" diameter, 1/64" to 1/32" deep 5 11 to 25 Pits of Pitting Index 5 6 More than 25 pits of Pitting Index 5 7 Pits larger than 1/16", but less than 1/8" in diameter, greater than 1/32"
deep, 100 or fewer in number Any pitting more severe than Pitting Index 8 9 Preferably, the solvent is an alcohol, where its presence allows the various constituents in the metal cleaning composition to be compatible and helps in preventing separation and/or gel formation. Preferably, the alcohols which are useful include branched- or straight-chain alcohols having 2 to 5 carbon atoms.
Date Regue/Date Received 2022-10-21 More preferably, ethanol and isopropanol are particularly useful aliphatic alcohols in the composition according to the present invention.
All of the above constituents are combined with water in the proportions indicated herein to obtain a metal cleaning composition according to the present invention. The metal cleaning composition may be obtained as a "concentrate", which can be used as such for certain applications or further diluted with water.
While the foregoing invention has been described in some detail for purposes of clarity and understanding, it will be appreciated by those skilled in the relevant arts, once they have been made familiar with this disclosure that various changes in form and detail can be made without departing from the true scope of the invention in the appended claims.

Date Regue/Date Received 2022-10-21

Claims

1. A chelating agent-free composition for use in metalworking cleaning, wherein said composition comprises:
- water;
- a caustic component;
- a solvent;
- an anionic surfactant;
- a nonionic surfactant;
- optionally, a corrosion inhibitor;
- a fatty alcohol polyglycol ether; and - a hydrophobic component.

2. The composition according to claim 1 where the solvent is selected from the group consisting of:
methanol; ethanol; isopropanol, 1-propanol; and glycol ether.

3. The composition according to claim 1 or 2 where the anionic surfactant comprises an alkyldiphenyloxide disulfonate.

4. The composition according to claim 1 to 3 where the alkyldiphenyloxide disulfonate is Dowfax C1OL.

5. The composition according to any one of claims 1 to 4 where the fatty alcohol polyglycol ether, is Emuldac 251 PE.

6. The composition according to any one of claims 1 to 5 where the nonionic surfactant is an ethoxylated alcohol.

7. The composition according to any one of claims 1 to 6 where the nonionic surfactant is Novel 23E3.

8. The composition according to any one of claims 1 to 7 where the hydrophobic component is a naphthenic mineral oil.

9. The composition according to any one of claims 1 to 8 where the hydrophobic component is pale oil 40.

Date Regue/Date Received 2022-10-21

10. The composition according to any one of claims 1 to 9 where the caustic component is selected from the group consisting of: potassium hydroxide or a modified caustic soda.

11. The composition according to any one of claims 1 to 10 where the solvent is present in an amount ranging from 5 to 15 wt % of the total weight of the composition.

12. The composition according to any one of claims 1 to 11 where the anionic surfactant is present in an amount ranging from 5 to 15 wt % of the total weight of the composition.

13. The composition according to any one of claims 1 to 12 where the fatty alcohol polyglycol ether is present in an amount ranging from 1 to 5 wt % of the total weight of the composition.

14. The composition according to any one of claims 1 to 13 where the nonionic surfactant is present in an amount ranging from 5 to 20 wt % of the total weight of the composition.

15. The composition according to any one of claims 1 to 14 where the hydrophobic component is present in an amount ranging from 2 to 5 wt % of the total weight of the composition.

16. The composition according to any one of claims 1 to 15 where the corrosion inhibitor is present in an amount ranging from 0.5 to 5 wt % of the total weight of the composition.

17. The composition according to any one of claims 1 to 16 where the caustic component is present in an amount ranging from 0.01 to 0.5 wt % of the total weight of the composition.

18. The composition according to any one of claims 1 to 17 where the pH of the composition ranges from 7 to 13.

19. The composition according to any one of claims 1 to 15 where the pH of the composition ranges from 8 to 12.

Date Regue/Date Received 2022-10-21