JP2002501105A - Paint stripping composition - Google Patents

Abstract

  (57) [Summary] The present invention relates to a composition for stripping a paint film, for example. The composition contains at least one carbocyclic ketone having 5 carbon atoms in the ring.

Description

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to a composition for removing a coating film, for example, a paint-based coating film.

[0002] The invention also relates to a method for stripping paint deposited on an object using the composition.

[0003] The first paint release compositions were based on methylene chloride and / or 1,1,1-trichloroethane (T.1.1.1.1.) (Eg, US Pat. No. 2,5,5).
No. 07,983 and German Offenlegungsschrift 2,524,752).

[0004] Such paint stripping compositions have the advantage of being very effective and inexpensive. However, they can cause environmental destruction and, in particular, depletion of the ozone layer (Montreal Protocol aiming at cessation of use of T.1.1.1.1, typically at the end of 1995). .

[0005] Such chlorinated solvents are lactams or lactones, usually N-methyl-2.
-Pyrrolidone or gamma-butyrolactone (U.S. Pat. No. 4,120,8)
10) or by a mixture of alkyl diesters of dibasic acids, which is a by-product of the production of the monomers necessary for the production of polyamides (DE-A 3,438,399). Progress has been made.

The above compositions are not always suitable for stripping different types of coatings such as water-based paints, oil-based paints, lacquers, varnishes and plastic resins.

[0007] US Patent 2,694,658 discloses the use of dimethyl sulfoxide as a paint stripping solvent. However, this type of solvent
It is very expensive and has the disadvantage of having to be used in large quantities.

[0008] EP-A-0,573,339 discloses a polar aprotic solvent, which contains one or more methoxy groups, has a flash point above 0 ° C. and a
Novel release compositions containing ethers having well-defined properties, such as gram molecular volumes lower than zero, are disclosed.

[0009] Therefore, the marketplace requires new release compositions.

[0010] More precisely, the invention is characterized in that it comprises at least one carbocyclic ketone containing 5 atoms in the ring, in particular for peeling paints. It is an object to provide a release composition.

The term “carbocyclic ketone containing 5 carbon atoms” refers to all ketone compounds containing 5 carbon atoms and having an optionally substituted saturated hydrocarbon ring.

This ring may have a substituent.

The number of substituents in the ring is up to four, but generally there is one or two substituents in the ring.

The nature of the substituents can vary considerably and there is no limit on the nature. However, for economic reasons, the ketone compound should not be too complex and in general this substituent will be an alkyl group containing from 1 to 4 carbon atoms, preferably a methyl or halogen atom, preferably a fluorine atom. Is an atom.

[0015] For the remainder of the present disclosure, the term "cyclopentanone" means cyclopentanone or substituted cyclopentanone.

Ketones which can be used in the compositions of the present invention and which may be mentioned are:

• cyclopentanone, • 2-methylcyclopentanone, • 3-methylcyclopentanone, • 2-chlorocyclopentanone, • 2,2-dimethylcyclopentanone, • 2,4-dimethylcyclopentanone Non-, 2,5-dimethylcyclopentanone, 3,4-dimethylcyclopentanone, 2,2,4-trimethylcyclopentanone, and cyclopentanone are preferred.

In a preferred variant of the invention, the stripping composition according to the invention combines a ketone as defined above with a polar aprotic solvent.

Examples of polar aprotic solvents which may be mentioned are acetylacetone, acetonitrile, dimethylsulphoxide, dimethylformamide, N-methylmorpholine, N-methyl-2-pyrrolidone and mixtures thereof.

[0020] Another type of solvent can be combined with the cyclopentanone, which is constituted by an aliphatic, cycloaliphatic or aromatic ether oxide.

Preferred examples that may be mentioned are:

1-tert-butoxy-2-methoxyethane, anisole, phenetol, ethylene glycol dimethyl ether, 1,2-dimethoxybenzene, 1,3-dimethoxybenzene, 1,4-dimethoxybenzene, -2-methoxy-1,3-dioxolane-Diethylene glycol dimethyl ether-1,2,3-trimethoxybenzene.

With respect to polar aprotic solvents, anisole, phenetole, acetylacetone, acetonitrile, dimethylformamide or N-2-methylpyrrolidone are
It is preferably used.

The present invention provides a composition for stripping paint containing, on a volume basis, (1) 1% to 90% of a polar aprotic solvent, and (2) 1% to 90% of a carbocyclic ketone. I will provide a.

Thus, preferred compositions of the present invention comprise, at least on a volume basis: (1) 20% to 80%, more preferably 20% to 50% of a polar aprotic solvent; It contains 80%, more preferably 50% to 80%, of a carbocyclic ketone.

The following are examples of compositions of the present invention.

(1) 1% to 90%, preferably 20% to 80%, more preferably 20% to 5%
0% acetylacetone, acetonitrile, dimethylformamide, N-methylmorpholine, N-methyl-2-pyrrolidone, 1-tert-butoxy-2-methoxyethane, anisole, phenetole, ethylene glycol dimethyl ether, 1,2-dimethoxybenzene, A polar aprotic solvent selected from 1,3-dimethoxybenzene, 1,4-dimethoxybenzene, 2-methoxy-1,3-dioxolan, diethylene glycol dimethyl ether, 1,2,3-trimethoxybenzene and mixtures thereof; (2) 1% to 90%, preferably 20% to 80%, more preferably 50% to 8%
0% of cyclopentanone The preferred composition of the present invention comprises: (1) 1% to 90%, preferably 20% to 80%, more preferably 20% to 5%.
0% of a polar aprotic solvent selected from acetylacetone, acetonitrile, dimethylformamide, N-methyl-2-pyrrolidone, anisole, phenetole and mixtures thereof, (2) 1% to 90%, preferably 20% to 80%, more preferably 50% to 8
Contains 0% cyclopentanone.

[0028] The composition of the present invention may also contain other conventional additives.

Examples of such additives that may be mentioned include co-solvents, surfactants, thickeners, activators, corrosion inhibitors, evaporation retarders or any other, unless it is a chlorinated solvent. Additives.

[0030] The addition of a co-solvent can generally increase the release performance of the composition by facilitating dissolution of the plasticizer present in the paint.

Examples of co-solvents that can be used are aromatic or aliphatic, having a flash point higher than 50 ° C., preferably higher than 70 ° C., such that the solvent cannot be classified as a flammable solvent. Is an odorless liquid hydrocarbon solvent.

[0032] Examples of such solvents derived from petroleum and having a high flash point are mineral spirits such as white spirit and naphtha.

Commercially available products that can be used in the compositions of the present invention include Exxon (Exx
on), ISOPAR®, Shell
From SOLTROL® and Ashland (A)
HI-SOL.RTM., especially SOLVESSO.RTM. 100, 150 and 200.

However, since these hydrocarbon derivatives are classified as Xn (hazardous substances), in order to avoid labeling the final product with Xn, they are gradually added to dialkyl of the dibasic aliphatic acid type. It is being replaced by ester solvents.

Thus, preferably at least one of the dibasic C ₄ -C ₆ aliphatic acids C ₁ -C ₆
C ₄ dialkyl ester is used.

The dibasic acid ester mixture is essentially a mixture of ester derivatives of adipic acid, glutaric acid and succinic acid. In particular, the alkyl group of the ester moiety is selected from methyl group and ethyl group. May also be a propyl, isopropyl, butyl, n-butyl or isobutyl group.

The above C ₄ -C ₆ diacids are in fact a by-product from producing adipic acid, one of the main monomers of the polyamide, and the dialkyl ester is generally Obtained by esterification of this by-product containing, by weight, 15% to 30% succinic acid, 50% to 75% glutaric acid and 5% to 25% adipic acid.

This dibasic acid ester is a commercially available product. Commercial products that may be mentioned in particular are Rhodiasolv RPDE® sold by Rhone-Poulenc and sold by Du Pont de Nemours. “Du Pont Dibasic
Esters) (registered trademark).

With respect to the amount of cosolvent to be used, 10 per 100 volumes of (1) and (2)
It is recommended to use 100 volumes, preferably 30-60 volumes, of co-solvent.

[0040] One or more surfactants can be added to the stripping composition. These surfactants facilitate the use of water to clean the composition on the substrate to be stripped, and in some cases enhance the stripping action.

Examples of anionic surfactants that may be mentioned are alkali metal soap type anionic surfactants.
Surfactant (C₈~ C₂₄Alkali salts of fatty acids), alkali sulfonates (C ₈ ~ C₁₃Alkylbenzene sulfonate, C₁₂~ C₁₆Alkyl sulfonic acid
Salt), oxyethylenated and sulfated C₆~ C₁₆Fatty alcohol, oxyethylene
And sulfated C₈~ C₁₃Alkylphenol and alkali sulfosuccinate (
C₁₂~ C₁₆Alkylsulfosuccinate). . . It is.

Nonionic surfactants that may be mentioned include ethoxylated or ethoxypropoxylated alkylphenols and ethoxylated or ethoxypropoxylated fatty alcohols, ethoxylated or ethoxypropoxylated triglycerides, ethoxylated or ethoxypropoxyl. Fatty acids, ethoxylated or ethoxypropoxylated sorbitan esters, ethoxylated or ethoxypropoxylated fatty amines, ethoxylated or ethoxypropoxylated di (1-phenylethyl) phenol and ethoxylated or ethoxypropoxylated tri (1- Phenylethyl) phenol.

The number of oxyethylenated (OE) and / or oxypropyleneated (OP) motifs of these nonionic surfactants usually depends on the desired HLB (hydrophilic / lipophilic balance). Between 2 and 100. Preferably, OE
And / or the number of OP motifs is in the range of 2-50.

Ethoxylated or ethoxypropoxylated alkylphenols generally include one or two straight-chain or branched alkyl groups containing 4 to 12 carbon atoms, especially octyl, nonyl or dodecyl. Is contained.

An example of a preferred nonionic surfactant that may be mentioned is nonylphenol ethoxylated with 2 to 9 ethylene oxide motifs.

Ethoxylated or ethoxypropoxylated fatty alcohols generally comprise 6 to 2
Containing two carbon atoms, the OE and OP motifs have been excluded from these members and are preferably ethoxylated.

Ethoxylated or ethoxypropoxylated triglycerides include triglycerides of animal or plant origin (eg, lard, sweat, peanut oil, butter oil, cottonseed oil, linseed oil, olive oil, palm oil, grape seed oil, fish oil, soybean Oil, castor oil, rapeseed oil, copra oil or coconut oil) and are preferably ethoxylated.

The term “ethoxylated triglyceride” as used in the present invention means both the product obtained by ethoxylation of triglyceride with ethylene oxide and that obtained by transesterification of triglyceride with polyethylene glycol.

The ethoxylated or ethoxypropoxylated fatty acid is an ester of a fatty acid (eg, oleic acid, stearic acid), and is preferably ethoxylated.

The term “ethoxylated fatty acids” includes products obtained by ethoxylation of fatty acids with ethylene oxide and those obtained by esterification of fatty acids with polyethylene glycol.

The ethoxylated or ethoxypropoxylated sorbitan ester is an ester of sorbitol cyclized with a C ₁₀ -C ₂₀ fatty acid such as lauric acid, stearic acid or oleic acid, and is preferably ethoxylated.

Ethoxylated or ethoxypropoxylated fatty amines are generally from 10 to 22
Containing two carbon atoms, the OE and OP motifs have been excluded from these members and are preferably ethoxylated.

The surfactant or surfactants may be, for example, on a weight basis relative to the total composition weight,
It can be used in an amount which can range from 0.1% to 10%, preferably from 0.5% to 5%.

For the composition of the present invention, it is desirable to include a thickener to make the composition applicable to vertical surfaces.

The use of common thickeners such as cellulose derivatives (ethyl cellulose, hydroxypropyl cellulose), xanthan gum, guar gum, carob gum, alginates, polyacrylates, starches, modified starches and modified clays can be used. it can.

The thickener is preferably present in an amount of 0.5% to 1% by weight based on the total composition weight.
It is used in an amount of 0%, preferably in the range of 1% to 3%.

Activators can be added to increase the rate of paint removal.
This is a small polar molecule that will help break the bond strength between the paint film and the substrate. Examples which may be mentioned are methyl phosphates or amines,
Preferred is formic acid in the form neutralized by triethanolamine (TEA).

The activator is preferably present in an amount of from 0.5% to 0.5% by weight based on the total composition weight.
It is used in an amount in the range of 2%, preferably about 1%.

The stripping composition also includes, for example, a corrosion inhibitor, preferably triethylammonium phosphate or sodium benzoate; an evaporation retarder, eg, 46 ° C.-5
Paraffin grease having a melting point in the range of 7 ° C. and aluminum oxide, silica, silicon carbide, tungsten carbide and silicon carbo nitride.
abrasive particles selected from the following types:

The compositions of the present invention allow paint to be stripped.

The term “paint” is generally used herein. This refers to all paints of polymeric nature deposited on the support, more particularly the paints themselves, varnishes and plastic resins.

This composition has particular application to oil paints, polyurethane paints, water-based paints, alkyd-urethane paints, acrylic-polyurethane paints and epoxy paints.

The paints are preferably used in the domestic and industrial sectors, especially in the construction industry.

The substrate to be cleaned or stripped may be of various properties.

The most common substrates are wood; steel, stainless steel, aluminum,
Metals such as copper and iron and their alloys; plastic materials and mineral glass.

Advantageously, the composition containing cyclopentanone and / or anisole and / or phenetol and / or DMF and / or NMP and / or acetylacetone and / or acetonitrile is preferably a paint of the polyester or polyurethane type Used to peel off.

The present invention also provides a method of peeling a paint from a substrate, the method comprising contacting the paint with a composition of the present invention.

The compositions of the present invention are prepared by simply mixing the various components at ambient temperature (typically 5 ° C. to 25 ° C.) using a stirrer or any other suitable equipment. can do.

The stripping method is performed by bringing an object or surface to be stripped into contact with the composition of the present invention.

This contact is continued until the paint swells, forms blisters and separates.

The object or surface to be stripped can be brought into contact with the composition of the invention in various ways.

These methods include dipping, spraying and application using a brush.

The contact is performed at a temperature in the range of 5 ° C. to 25 ° C., that is, at ambient temperature.

The contact time is in the range from 15 to 120 minutes.

[0075] Cyclopentanone alone constitutes the most effective solvent for polyester and polyurethane paints.

Cyclopentanone is advantageously combined with anisole or phenetole.

[0077] The compositions of the present invention do not contain chlorinated solvents and are stable when stored for at least one year.

An embodiment of the present invention will now be described.

In the examples, the percentages of the components of the release composition are given on a volume basis unless otherwise indicated.

These examples are given by way of illustration and are in no way limiting.

Example First, the operation plan according to the example will be described.

[0082] Four drops of the formulation were applied to the painted plate and the time required for swelling or "bloating" of the paint was recorded using a chronometer without any mechanical assistance. This time was recorded in minutes or hours if the stripping time exceeded 60 minutes.

The formulations were tested on painted plates manufactured by ETALON.

Polyurethane paint reference (90 × 190 ZESPHOS + P
U) Batch No. 7163-7; White Polyester Paint (90 × 190 Zesphos + Blank / 389) Batch No. 7162-7.

The following results were obtained.

[0086]

[Table 1] Cyclopentanone alone is the most effective solvent for polyester and polyurethane paints.

The release power of cyclopentanone can be improved by combining it with a solvent such as anisole, NMP, DMF, acetonitrile or acetylacetone, especially for polyurethane paints.

──────────────────────────────────────────────────続 き Continuation of front page (81) Designated country EP (AT, BE, CH, CY, DE, DK, ES, FI, FR, GB, GR, IE, IT, LU, MC, NL, PT, SE ), OA (BF, BJ, CF, CG, CI, CM, GA, GN, GW, ML, MR, NE, SN, TD, TG), AP (GH, GM, KE, LS, MW, SD, SZ, UG, ZW), EA (AM, AZ, BY, KG, KZ, MD, RU, TJ, TM), AL, AM, AT, AU, AZ, BA, BB, BG, BR, BY, CA, CH, CN, CU, CZ, DE, DK, EE, ES, FI, GB, GE, GH, GM, HR, HU, ID, IL, IN, IS, JP, KE, KG , KP, KR, KZ, LC, LK, LR, LS, LT, LU, LV, MD, MG, MK, MN, MW, MX, NO, NZ, PL, PT, RO, RU, SD, SE, SG, SI, SK, SL, TJ, TM, TR, TT, UA, UG, US, UZ, VN, YU, ZWF terms (reference) 4J038 BA021 BA091 BA101 BA121 BA141 CG001 JA02 JA26 JA28 JA33 JA38 JA57 JA59 JA64 JB13 JB21 JB27 JB39 JC09 JC14 KA06 KA09 LA06 MA06 MA09 NA10 PB02 PB05 PB07 PC02 PC08

Claims (18)

[Claims] 1. A composition for stripping coatings, in particular paint-based coatings, characterized in that it contains at least one carbocyclic ketone containing 5 atoms in the ring. 2. The carbocyclic ketone is cyclopentanone or a cyclopentanone wherein the ring has an alkyl group containing 1 to 4 carbon atoms, preferably a methyl group or a halogen atom, preferably a fluorine atom. The composition according to claim 1, characterized in that: 3. The composition according to claim 1, further comprising a polar aprotic solvent. 4. The polar aprotic solvent is acetylacetone, acetonitrile, dimethylsulfoxide, dimethylformamide, N-methylmorpholine, N-methylmorpholine,
The composition according to any one of claims 1 to 3, wherein the composition is -methyl-2-pyrrolidone or a mixture thereof. 5. The polar aprotic solvent is an ether, preferably 1-te
rt-butoxy-2-methoxyethane, anisole, phenetole, ethylene glycol dimethyl ether, 1,2-dimethoxybenzene, 1,3-dimethoxybenzene, 1,4-dimethoxybenzene, 2-methoxy-1,3-dioxolan, diethylene glycol dimethyl ether The composition according to any one of claims 1 to 4, wherein the composition is 1,2,3-trimethoxybenzene. 6. On a volume basis, (1) 1% to 90%, preferably 20% to 80%, more preferably 20% to 5%.
0% of a polar aprotic solvent, (2) 1% to 90%, preferably 20% to 80%, more preferably 50% to 8%
The composition according to claim 1, comprising 0% of a carbocyclic ketone. 7. On a volume basis, (1) 1% to 90%, preferably 20% to 80%, more preferably 20% to 5%
0% acetylacetone, acetonitrile, dimethylformamide, N-methylmorpholine, N-methyl-2-pyrrolidone, 1-tert-butoxy-2-methoxyethane, anisole, phenetole, ethylene glycol dimethyl ether, 1,2-dimethoxybenzene, A polar aprotic solvent selected from 1,3-dimethoxybenzene, 1,4-dimethoxybenzene, 2-methoxy-1,3-dioxolan, diethylene glycol dimethyl ether, 1,2,3-trimethoxybenzene and mixtures thereof; (2) 1% to 90%, preferably 20% to 80%, more preferably 50% to 8%
The composition according to claim 1, comprising 0% of cyclopentanone. 8. On a volume basis, (1) 1% to 90%, preferably 20% to 80%, more preferably 20% to 5%
0% of a polar aprotic solvent selected from acetylacetone, acetonitrile, dimethylformamide, N-methyl-2-pyrrolidone, anisole, phenetole and mixtures thereof, (2) 1% to 90%, preferably 20% to 80%, more preferably 50% to 8
The composition according to claim 1, comprising 0% of cyclopentanone. 9. The method according to claim 1, which comprises a cosolvent, a surfactant, a thickener, an activator, a corrosion inhibitor, an evaporation retarder or all other additives. The composition according to claim 1. 10. The composition according to claim 9, wherein the cosolvent is a C ₁ -C ₄ dialkyl ester of at least one C ₄ -C ₆ dibasic aliphatic acid. 11. A composition according to claim 1, for removing paints, varnishes and plastic resins. 12. The composition according to claim 1, for removing oil-based paints, polyurethane paints, water-based paints, alkyd-urethane paints, acrylic-polyurethane paints and epoxy paints. 13. The following substrates: wood; metals such as steel, stainless steel, aluminum, copper and iron and their alloys; plastic materials and for removing coatings deposited on mineral glass. The composition according to any one of claims 1 to 12. 14. The composition according to claim 1, wherein the different components are simply mixed using a stirrer or any other suitable device. Production method. 15. A method for stripping a coating film deposited on a substrate, wherein the coating film is brought into contact with the composition according to any one of claims 1 to 10. 16. The method according to claim 15, wherein the contacting is continued until the paint swells, forms blisters and separates. 17. The method according to claim 15, wherein the contacting is effected by all means, preferably by dipping, spraying and applying using a brush. 18. The method according to claim 15, wherein the contact is performed at an ambient temperature.
A composition according to any one of claims 7 to 10.