MXPA97007096A - Cleaning and / or decapating composition based on determined and effective ester - Google Patents

Abstract

The present invention relates to a pickling and / or cleaning composition containing in volume: (a) 1 to 90% at least one dialkyl ester with 1 to 4 carbon atoms, at least one aliphatic diacid with 4 to 6 carbon atoms; and (b) from 99 to 1%, at least one of the selected ones among those having a flash point greater than 5øC, at least one methoxy group per molecule, and with a molecular weight less than 2.

Description

CLEANSING AND / OR DECAPATING COMPOSITION BASED ON DIARY AND ETHER ESTER The present invention relates to a composition that allows both to remove coatings, for example, based on paint and clean objects contaminated by oils or fats. The first stripping and degreasing compositions of the type indicated above were based on methylene chloride and / or trichloro-1,1-ethane (T.1.1.1) (see, for example, US Memoirs US-A). 2,507,983 and DE-A 2,524,752 Such compositions have the advantage of being effective and inexpensive, however, these compositions can cause damage to the environment, and more particularly to the ozone layer ( Montreal about the halting of the use of T.1.1.1, normally until the end of 1995.) An important advance was made by the replacement of these chlorinated solvents, either by lactams or lactones, among which the most usual are N-methyl-2-pyrrolidone or gamma-butyrolactone (US Report No. 4,120,810), or by a mixture of alkyl diester of diacids which is a by-product of the necessary monomer-producing industry for the preparation of polyamides (German report DE-3.438.399). The compositions mentioned above are not always adapted to the pickling of coatings of different nature, such as water-based paints, oil paints, lacquers, varnishes and plastic resins, and above all they can be said to be ineffective for both coating pickling and the cleaning of various objects to remove oils and fats. The object of the present invention is to replace a composition that has precisely combined efficiency, that is, for pickling and for cleaning. It also aims to propose a composition of the type mentioned above which, according to a variant, can be free of solvents. It also has the purpose of offering a composition of the type mentioned above that is stable to storage for at least one year. These and other additional objects are achieved by the present invention, which in effect relates to a pickling and / or cleaning composition that carries in volume: a) from 1 to 90% at least one dialkyl ester with 1 to 4 carbon atoms; carbon, of at least one aliphatic diacid with 4 to 6 carbon atoms; b) from 99 to 1% of at least one ether selected from the ethers having: a flash point higher than 5 ° C, at least one methoxy group per molecule - a molar weight, that is, a molar mass lower than 200. The composition according to the invention contains at least a minimum of 1 to 90% by volume, and preferably between 10 and 80% of a dialkyl ester with 1 to 4 carbon atoms, at least one aliphatic diacid with 4 to 6 carbon atoms. The mixture of diacid esters are esters derived essentially from glutaric and succinic adipic acids, the alkyl groups being selected from the ester moiety, especially between the methyl and ethyl groups, however, the groups can also be propyl, isopropyl, butyl , normal butyl and isobutyl. As already noted above, the diacids with 4 to 6 carbon atoms, mentioned previously, are in fact by-products of the preparation of adipic acid which is one of the main monomers of the polyamides, and the dialkyl esters are obtained with esterification of this by-product which generally contains by weight 15% to 30% succinic acid, 50% to 75% gultárico acid, and 5% to 25% adipic acid. Diacid esters are products that are found in the market. As commercial products, the Rhodiasolv RPDE® marketed by the Rhône-Poulenc Company and the Du Pont Dibasic Esters® marketed by the Du Pont de Nemours Company can be mentioned more particularly, the composition according to the invention also contains by volume from 99% to 1%, preferably from 90% to 20% by weight of at least one ester selected from ethers having: a flash point greater than 5 ° C, at least one methoxy group per molecule, a molar mass, that is, molecular weight less than 200. As the ether usable in the compositions, according to the invention, the following can be mentioned: l-tert-butoxy-2-methoxyethane-anisole, 1-4-dimethoxybenzene, - ethylene glycol dimethyl ether, 1, 2-dimethoxybenzene, 2-methoxy-l, 3-dioxolane, diethylene glycol dimethyl ether, 1,2,3-trimethoxybenzene, 1,3-dimethoxybenzene. The compositions according to the invention may also contain at least one of the products mentioned below. c) At least one liquid hydrocarbon solvent, aliphatic or aromatic and odorless, and having a flash point higher than 40 ° C, and preferably higher than 70 ° C, in such a way that this solvent is not classified within the liquids flammable Examples of such petroleum-derived solvents with a high flash point are especially mineral spirits, such as "white spirit" and naphthas. As commercial products, in the compositions, according to the invention, ISOPAR® from Exxon, SOLTROL® from Shell, and the HI-SOL® solvents from Ashland can be used. It is recommended to use 10 to 100 volumes, and preferably 30 to 60 volumes of c) per 100 volumes of a) + b). Mention may also be made of the compounds having an aliphatic hydrocarbon chain, saturated, or comprising at least one unsaturation, substituted by at least one radical of the alkyl, aryl or alkylaryl type. More particularly, the aliphatic chain comprises from 3 to 12 carbon atoms, and preferably from 4 to 10 carbon atoms, these values being given taking into account the longest hydrocarbon chain of the molecule, with the exception of the substituents. According to a variant, the aliphatic hydrocarbon chain is substituted by two aryl and / or alkylaryl groups. More particularly, the aryl radical carries 6 carbon atoms, and the alkylaryl radical corresponds to an aromatic nucleus substituted by at least one alkyl group, preferably with 1 to 4 carbon atoms. In such a case, the bond between the alkylaryl substituent and the aliphatic hydrocarbon chain of the compound can take place by means of one of the carbons of the alkyl portion of this compound, or preferably directly by one of the carbon atoms of the aromatic nucleus. As already indicated, the aliphatic hydrocarbon chain of the compound can also comprise at least one alkyl radical, which more particularly carries from 1 to 4 carbon atoms, with the methyl group being preferred. Among the compounds of this type, mention may be made of 2,4-diphenyl, 2-methyl-3-pentene, 2,4-diphenyl, 2-methyl-pentane, these compounds being used alone or as a mixture. d) At least one nonionic surfactant selected preferably from ethoxylated or ethoxylated propoxylated alkylphenols and ethoxylated or ethoxylated propoxylated fatty alcohols, with a content which, for example, may be between 0.1% and 10%, and preference between 0.5% and 5% by weight in relation to the total weight of the composition. These surfactants facilitate the washing with water of the compositions on the substrate to be stripped or cleaned, and in certain cases, they serve to accelerate the stripping and / or cleaning action. As other surfactants, the following can also be used: ethoxylated or ethoxy-propoxylated triglycerides, ethoxylated or ethoxy-propoxylated fatty acids, ethoxylated or ethoxy-propoxylated sorbitan esters. ethoxylated or ethoxy-propoxylated fatty amines, ethoxylated or ethoxylated propoxylated di (1-phenylethyl) phenols, ethoxylated or ethoxy-propoxylated tri (1-phenylethyl) phenols. the number of oxyethylene (OE) and / or oxypropylene (OP) motifs of these nonionic surfactants usually ranges from 2 to 100, depending on the desired HLB (balance of hydrophilicity / lipophilicity). The number of OE and / or OP motifs is preferably between 2 and 50. The ethoxylated or ethoxy-propoxylated fatty alcohols generally contain from 6 to 22 carbon atoms., excluding the OE and OP reasons of these numbers, and preferably they are ethoxylated. Ethoxylated or ethoxylated propoxylated triglycerides can be triglycerides of vegetable or animal origin (such as lard, tallow, peanut oil, butter oil, cottonseed oil, flaxseed oil, olive, palm oil, raisin cucumber oil, grape seed oil, fish oil, soybean oil, castor oil, rapeseed oil, copra oil, coconut oil) , and they are preferably ethoxylated. The ethoxylated or ethoxy-propoxylated fatty acids are esters of fatty acids (such as, for example, oleic acid and stearic acid), and preferably are ethoxylated. The ethoxylated or ethoxy-propoxylated sorbitan esters are esters of cyclized sorbitol of fatty acids with 10 to 20 carbon atoms, such as lauric acid, stearic acid or oleic acid, and are preferably ethoxylated. The term ethoxylated triglyceride contemplates, within the present invention, both the products obtained by ethoxylation of a triglyceride by ethylene oxide, and those obtained by transesterification of a triglyceride by a polyethylene glycol. Likewise the term ethoxylated fatty acid includes both the products obtained by ethoxylation of a fatty acid by ethylene oxide, and those obtained by esterification of a fatty acid by a polyethylene glycol. The ethoxylated or ethoxy-propoxylated fatty amines generally have from 10 to 22 carbon atoms, excluding the OE and OP motifs of these numbers, and they are preferably ethoxylated. Ethoxylated or ethoxy-propoxylated alkylphenols generally have one or two straight or branched chain alkyl groups having 4 to 12 carbon atoms, especially octyl, nonyl or dodecyl. By way of examples of nonionic surfactants from the group of ethoxylated or ethoxylated propoxylated alkylphenols, that is, of the ethoxylated di (1-phenyl-1-ethyl) phenols and tri (1-phenyl-1-ethyl) phenols ethoxylated or ethoxy-propoxylates, there may be mentioned: di (1-phenylethyl) phenol ethoxylated with 5 OE motifs, di (1-phenylethyl) phenol ethoxylated with 10 OE motifs, tri (1-phenyl-ethyl) phenol ethoxylated with 16 OE motifs, tri (1-phenylethyl) phenol ethoxylated with 20 OE motifs, tri (1-phenylethyl) phenol ethoxylated with 25 OE motifs, tri (1-phenyl-ethyl) phenol ethoxylated with 40 OE motifs, ethoxy-propoxylated tri (1-phenyl-ethyl) phenols with reasons for OE + OP, - nonylphenol ethoxylated with 2 OE-based, nonylphenol ethoxylated with 4 OE-based, nonylphenol ethoxylated with 6 OE-based, nonylphenol ethoxylated with 9 OE-based, nonylphenol ethoxy-propoxylated with 25 EO + OP, ethoxy-propoxylated nonylphenols with 30 OE + OP motifs, ethoxy-propoxylated nonylphenols with 40 OE + OP motifs, ethoxy-propoxylated nonylphenols with 55 OE + OP motifs, ethoxy-propoxylated nonylphenols with 80 OE + OP motifs. e) At least one thickening agent preferably used with a content between 0.5% and 10% by weight in relation to the total weight of the composition, preferably between 1% and 3%. Classic thickening agents can be used, such as cellulose derivatives (ethylcellulose, hydroxypropylcellulose), xanthan gums, guar, carob, alginates, polyacrylates, starches, modified starches and modified clays. f) At least one aprotic polar cosolvent, such as, for example, lactams or lactones, such as N-methyl-2-pyrrolidone, or gamma-butyrolactone, the alkylene glycol esters, acetonitrile, dimethylformamide, dimethylsulfoxide and N-methylmorpholine. It is possible to use, for example, from 10% to 40% by volume of the cosolvent in relation to the total volume of the composition. g) Abrasive particles selected from aluminum oxide, silica, silicon carbide, tungsten carbide and silicon carbonitride.

The compositions, according to the invention, allow the cleaning of oils and fats, as well as the pickling of paints and plastic resins. The substrates that must be cleaned or stripped can be of a very varied nature. The most common are wood, metals and their alloys, such as steel, stainless steel, aluminum, copper, plastic materials, mineral glasses. According to the present invention, the process for cleaning and / or pickling is as follows: a) Putting in contact the object to be cleaned with the formulation of the present invention by immersion (with or without agitation) or spraying. The temperature of the contact is between 5 ° C and 50 ° C. The contact time is between 1 minute and 60 minutes. In the case of degreasing, the composition of the present invention allows total or partial solubilization of the oils that must be eliminated. In the case of pickling, the composition of the present invention allows the removal of the resins that must be removed. b) Rinse with water of the formulation for cleaning, in accordance with the present invention.

The cleaning and stripping actions of the present invention are illustrated in the following examples: A) Degreasing of a paraffinic oil; "Total 200 Neutral®": The degreasing composition is as follows (% by volume): 34.33% of RPDE 34.33% of anisol 29.33% of white alcohol, that is, hite Spirit - 1% nonylphenol 9 OE 1% nonylphenol 12 OE This formulation allows to solubilize the Total 200 Neutral oil at room temperature up to 30% by weight. The substrate used is a steel plate (panel Q, type R), previously cleaned. To get greased, the plate is immersed for two minutes in oil, and then stored for 6 hours. The greased plate is then immersed in the cleaning composition, cited above, for a time tn, at room temperature. The plate is rinsed under running water for 5 to 10 seconds on each side (flow rate: 2 liters per minute, temperature 17 ° C). The cleaning of the plate is evaluated by means of the water film test (Water Break test, ASTM F22-65, 1992). For the purpose of completely cleaning the steel plate greased with the Total 200 Neutral oil with the cleaning composition, cited above, the immersion time, tn, required is 15 seconds. The operating mode mentioned above is reproduced, except that composition C2 is used instead of composition Cl, which has the following composition: 68% RPDE, 30% Solvexo 200 (hydrocarbon fraction marketed by Exxon and with a point of inflammation 98 ° C), 1% nonylphenol 9 OE, - 1% nonylphenol 1 OE The necessary immersion time is 30 seconds for this composition which, due to the absence of the anisole, does not form part of the invention, and is twice less effective B) Pickling of plastic resins from a glass support: Glass discs are fouled by reticulated plastic resins. These plastic resins are polycarbonates of the "bisalyl, diethylene glycol carbonate", and "bisphenol A, bisalyl, carbonate" type.

The stripping composition is as follows: 70% RPDE 30% anisole The glass supports soiled with the two resins are immersed in the composition mentioned above. 50 ° C, without agitation. After 30 minutes, the two reticulated plastic resins of the glass supports are completely detached.

Claims (9)

1. A pickling and / or cleaning composition carrying in volume: a) from 1 to 90% at least one dialkyl ester with 1 to 4 carbon atoms, of at least one aliphatic diacid with 4 to 6 carbon atoms; b) from 99 to 1% of at least one ether selected from ethers having: - a flash point greater than 5 ° C, at least one methoxy group per molecule, and a molar weight, ie a molar mass lower than 200.

2. The composition according to claim 1, characterized in that the ether b) is selected from: l-tert-butoxy-2-methoxyethane-anisole, 1-4-dimethoxybenzene, ethylene glycol dimethyl ether, 1,2-dimethoxybenzene, -2- methoxy-l, 3-dioxolane, diethylene glycol dimethyl ether, 1,2,3-trimethoxybenzene, 1,3-dimethoxybenzene.

3. The composition according to claim 1, characterized in that it further comprises c), at least one liquid hydrocarbon solvent, aliphatic or aromatic and odorless, and having a flash point greater than 40 ° C, preferably greater than 70 °. C, in such a way that this solvent is not classified in flammable liquids.

4. The composition according to claim 3, characterized in that it carries from 10 to 100 volumes, preferably from 30 to 60 volumes of c) per 100 volumes of a) + b). The composition according to any of the preceding claims, characterized in that it also contains d), at least one nonionic surfactant, preferably selected from ethoxylated or ethoxylated propoxylated alkylphenols and ethoxylated or ethoxy-propoxylated fatty alcohols, with a content between 0.1% and 10% by weight. 6. The composition according to any one of the 1 to 5, characterized in that it contains from 0.5 to 10% by weight of a thickening agent. The composition according to any of the preceding claims, characterized in that it also bears an aprotic polar cosolvent. The composition according to claim 7, characterized in that the cosolvent selected from N-2-methyl-pyrrolidone or gamma-butyrolactone, alkylene glycol ethers, nitrile oil, dimethylformamide, dimethyl sulfoxide and N-methylmorpholine. 9. The composition according to any of the preceding claims, characterized in that it also contains abrasive particles.