SOLVENT COMPOSITIONS

Abstract

SOLVENT COMPOSITIONS The present invention relates to a solvent composition for solvent-based paints or other coatings characterized in that it comprises a combination of dimethyl glutarate and at least one other compound selected from isobutyl acetate, ethyl lactate, dimethyl 2-methylglutarate, 2-methyltetrahydrofuran, ethyl acetate, cyclopentyl methyl ether, dithoxymethane, dimethyl carbonate, dimethyl succinate, benzyl alcohol, dimethyl adipate, and glyceryl triacetate. Fig. 1

Description

Title of the invention: SOLVENT COMPOSITIONS technical field

[0001] The present invention relates to solvent compositions, particularly for cleaning solvent-based paints, and more specifically for cleaning equipment used in the preparation and / or application of industrial paints. PRIOR TECHNIQUE

[0002] At the industrial level, paints are applied as a coating using equipment such as pumps, hoses, spray guns, brushes, or rollers. This equipment must be cleaned after the paint has been applied. Similarly, the equipment used to prepare the paint must be cleaned after the paint has been prepared. Since these paints are solvent-based, cleaning is carried out using solvents.

[0003] Many solvents, for example organic or water-based, are available today. However, depending on their composition, these have varying characteristics of effectiveness, hazard during use or storage, and pollution.

[0004] Indeed, paints used in industry, for example to coat mechanical parts, have varying compositions. They may be based on polyepoxide, polyurethane, or other types of polymers. Some solvents are not suitable for dissolving all types of paint and may leave residues or even create precipitates.

[0005] Furthermore, the flash point of a solvent is a crucial characteristic in terms of hazard. Indeed, the flash point determines the flammability of the solvent. It is the lowest temperature at which a product releases enough vapor to form a flammable mixture with air. A solvent with a flash point that is too low relative to its conditions of use or storage therefore presents serious risks.

[0006] Finally, it is known that solvents are one of the main sources responsible for the emission of volatile organic compounds, or VOCs. Now, more and more companies are adopting a strategy to reduce the environmental impact of their industrial processes and are implementing environmental management systems, particularly those compliant with current standards such as ISO 14001. Description of the invention

[0007] The object of the present invention is to provide solvent compositions, in particular for cleaning equipment for the preparation and / or application of solvent-based paints or other surface coatings, which offer both a certain effectiveness for these paints, a reduction in the risks of flammability related to the flash point during use or storage and a controlled environmental impact, particularly in terms of volatile organic compound emissions.

[0008] For this purpose, the invention relates to a composition of solvents for paints or other coatings, characterized in that it comprises dimethyl glutarate and at least one other compound selected from isobutyl acetate, ethyl lactate, dimethyl 2-methylglutarate, 2-methyltetrahydrofuran, ethyl acetate, cyclopentyl methyl ether, dithoxymethane, dimethyl carbonate, dimethyl succinate, benzyl alcohol, dimethyl adipate, glycerol triacetate.

[0009] The composition according to the invention proves to be quite effective in dissolving solvent-based paints generally used in industry, such as primers, base coats, top coats, varnishes, in particular paints or other coatings based on polyurethane, polyepoxides or other types of polymers, and thus effectively cleaning paint preparation and / or application equipment.

[0010] The composition according to the invention can be used with a limited risk of flammability. Indeed, whatever the proposed combinations of components, these will present a minimum flash point suitable for the conditions of use and storage.

[0011] Thus, advantageously, the composition according to the invention has a flash point greater than or equal to 39°C.

[0012] The flash point can be determined according to known methods, in a closed cup, in particular by following EN ISO 3679 (or any other current standard specifying flash point test procedures for paints).

[0013] Advantageously, the composition has a volatile organic compound content of less than 50% by mass.

[0014] The volatile organic compound (VOC) content can be measured using known methods, in accordance with EN ISO 11890-1 (or any other applicable standard specifying VOC measurement procedures for paints), in particular following measurement method 1 as described in EN ISO 11890-1. According to this method, the mass percentage of volatile organic compounds is calculated using the following formula:

[0015] VOC^\QQ-NV -Ww

[0016] in which:

[0017] VOC is the content of volatile organic compounds, as a percentage by mass;

[0018] NV is the content of non-volatile compounds as a percentage by mass;

[0019] Ww is the water content, as a percentage by mass.

[0020] Preferably, the composition comprises at least 40% by volume of dimethyl glutarate, relative to the total volume of the composition.

[0021] According to a preferred embodiment of the invention, the composition comprises dimethyl glutarate in combination with isobutyl acetate and / or ethyl lactate.

[0022] Advantageously, the composition consists solely of dimethyl glutarate in combination with isobutyl acetate and / or ethyl lactate.

[0023] Advantageously, the composition comprises between 50% and 80% dimethyl glutarate and between 20% and 50% isobutyl acetate and / or ethyl lactate, by volume relative to the total volume of the composition.

[0024] According to one embodiment, the composition comprises between 50% and 55% dimethyl glutarate, between 30% and 35% isobutyl acetate and between 20% and 25% ethyl lactate, by volume relative to the total volume of the composition.

[0025] According to another embodiment, the composition comprises between 50% and 55% dimethyl glutarate, between 30% and 35% ethyl lactate and between 20% and 25% isobutyl acetate, by volume relative to the total volume of the composition.

[0026] According to another embodiment, the composition comprises between 50% and 55% dimethyl glutarate and between 45% and 50% ethyl lactate or isobutyl acetate, by volume relative to the total volume of the composition.

[0027] According to another embodiment, the composition comprises between 70% and 80% dimethyl glutarate and between 20% and 30% isobutyl acetate, by volume relative to the total volume of the composition.

[0028] Preferably, the composition according to the invention comprises at most 20% of a compound selected from dimethyl 2-methylglutarate, 2-methyltetrahydrofuran, ethyl acetate, cyclopentyl methyl ether, dithoxymethane, dimethyl carbonate, dimethyl succinate, benzyl alcohol, dimethyl adipate, glycerol triacetate or one of their mixtures, by volume relative to the total volume of the composition.

[0029] The invention further relates to a method for cleaning equipment for preparing and / or applying solvent-based paints or other coatings, characterized in that it comprises at least one step of cleaning said equipment using a solvent composition as defined above.

[0030] The features of the invention mentioned above, as well as others, will become clearer upon reading the following examples and in connection with the accompanying drawing below:

[0031] [Fig.1] is an illustration of a device used to determine the effectiveness of solvent compositions according to the invention.

[0032] EXAMPLES

[0033] Example 1: Efficiency tests and flash point measurement

[0034] Five solvent compositions (Sol 1; Sol 2; Sol 3; Sol 4; Sol 5) according to the invention were prepared according to the mixtures indicated in Table 1.

[0035] Their effectiveness in dissolving different types of paints was compared to that of a commercial control solvent.

[0036] The trade names of the paints, as well as their main component, are also indicated in Table 1.

[0037] Table 1 below shows the results of the efficiency tests, as well as the flash point of each solvent composition.

[0038] The effectiveness in dissolving different types of paint was determined using the device 100 illustrated in [Fig. 1]. The device 100 consists of a burette holder 101, having a base 102, a graduated burette 103, and an aluminum test tube 104. The burette 103 is filled with 10 ml of solvent. The distance between the tip of the graduated burette 103 and the aluminum test tube 104 is 10 cm. The aluminum test tube 104 and the base 102 form an angle of 45°. A strip of solvent-based paint 105, approximately 1 cm wide and approximately 30 µm thick, is applied across the entire width of the test specimen 104. The amount of solvent required to dissolve the layer of paint 105 is then measured.

[0039] [Tables 1] Formulations Control solvent Recycled control solvent Sol 1 Sol 2 Sol 3 Sol 4 Sol 5 Paints 54-58.8% butyl acetate 40.7-41.5% isobutanol 58-65% butyl acetate 27-37% isobutanol 50% dimethyl glutarate 50% isobutyl acetate 75% dimethyl glutarate 25% isobutyl acetate 50% dimethyl glutarate 20% isobutyl acetate 30% ethyl lactate 50% dimethyl glutarate 30% isobutyl acetate 20% ethyl lactate 50% dimethyl glutarate 50% ethyl lactate Paint manufacturer 1 Primer (epoxy) 0.65 ml 0.52 ml 1.15 ml 0.52 ml 0.95 ml 0.30 ml 0.47 ml Base coat (Hane polyuret) 2.68 ml 2.10 ml 1.32 ml 0.68 ml 1.55 ml 0.50 ml 0.70 ml Top coat (hane polyuret) 0.62 ml 0.52 ml 0.43 ml 0.23 ml 0.47 ml 0.23 ml 0.37 ml CC varnish (hane polyuret) 0.47 ml 0.39 ml 0.20 ml 0.50 ml 0.35 ml 0.47 ml 0.43 ml Paint manufacturer 2 Primer (epoxy) 0.63 ml 0.43 ml 5.00 ml 5 ml 1.85 ml 0.62 ml 0.77 ml Base coat (hane polyuret) 0.43 ml 0.21 ml 0.58 ml 0.42 ml 1.28 ml 0.55 ml 0.80 ml Top coat (hane polyuret) 0.15 ml 0.28 ml 0.23 ml 0.30 ml 0.40 ml 0.28 ml 0.35 ml CC varnish (polyurethane hane) 0.62 ml 0.37ml 0.13 ml 0.73 ml 0.33 ml 0.32 ml 0.50 ml Paint manufacturer 3 Primer (epoxy) 1.00 ml 0.59ml 1.67ml 0.52 1.02 ml 0.20 ml 0.52 ml Base coat (polyurethane) 0.97 ml 0.40 ml 0.38 ml 0.22 ml 0.60 ml 0.18 ml 0.50 ml Top coat (polyurethane) 0.58 ml 0.45 ml 0.27 ml 0.38 ml 0.63 ml 0.25 ml 0.72 ml CC varnish (polyurethane) 0.58 ml 0.52 ml 0.32 ml 0.18 ml 0.40 ml 0.15 ml 0.50 ml Efficiency compared to recycled control solvent (% of light gray squares) / / 58% 50% 42% 75% 42% Efficiency compared to control solvent (% of light gray squares) / / 67% 67% 50% 92% 58% (more dark grey squares) Flash point 26°C 26°C 39.5°C 47.5°C 41°C 42.5°C 61°C

[0040] It is first noted that the five solvents according to the invention have a flash point above 39°C, whereas the control solvent has a flash point of 26°C. At such a value, the control solvent cannot be used safely, while the five solvents according to the invention can be used and stored more safely.

[0041] Furthermore, the five solvents according to the invention proved effective in dissolving all the layers of paint. Their effectiveness, compared to that of the controls, is significantly higher. Indeed, compared to the control solvent, solutions 1, 2, 3, 4, and 5 exhibited efficiencies of 58%, 50%, 42%, 75%, and 42%, respectively. Compared to the recycled control solvent, solutions 1, 2, 3, 4, and 5 exhibited efficiencies of 67%, 67%, 50%, 92%, and 58%, respectively.

[0042] It is noted in particular that solvent 4 stands out in terms of efficiency.

[0043] Example 2: volatile organic compound content

[0044] The volatile organic compound (VOC) content of the 5 solvent compositions according to the invention is presented in Table 2.

[0045] [Tables2] Soil 1 Soil 2 Soil 3 Soil 4 Soil 5 CAS No. VOC% Vapor pressure at 20°C (Pa) Dimethyl glutarate (L) 545 817.5 545 545 545 1119- 40-0 0% 8.3 Ethyl lactate (L) 0 0 206.6 206.6 516.5 97-64-3 100%? Isobutyl acetate (L) 435.5 217.7 5 261.3 261.3 0 110-1 9-0 100% 2100 Mass for IL 980.5 1035.25 1012.9 1012.9 1061.5 VOC g / L 435.5 217.7 5 467.9 467.9 516.5 % Theoretical VOC 44.42% 21.03% 46.19% 46.19% 48.66%

[0046] The five solvents according to the invention have an acceptable VOC content of less than 50%, whereas the control solvent has a VOC content of 100%.

Claims

Demands

1. Composition of solvents for paints or other coatings, characterized in that it comprises between 50% and 80% dimethyl glutarate and between 20% and 50% isobutyl acetate or a mixture of isobutyl acetate and ethyl lactate, by volume relative to the total volume of the composition.

2. Composition according to claim 1, characterized in that it has a flash point greater than or equal to 39°C.

3. Composition according to claim 1 or 2, characterized in that it has a volatile organic compound content of less than 50%, by mass.

4. Composition according to any one of the preceding claims, characterized in that it comprises between 50% and 55% dimethyl glutarate, between 30% and 35% isobutyl acetate and between 20% and 25% ethyl lactate, by volume relative to the total volume of the composition.

5. Composition according to any one of claims 1 to 3, characterized in that it comprises between 50% and 55% dimethyl glutarate, between 30% and 35% ethyl lactate and between 20% and 25% isobutyl acetate, by volume relative to the total volume of the composition.

6. Composition according to any one of claims 1 to 3, characterized in that it comprises between 70% and 80% dimethyl glutarate and between 20% and 30% isobutyl acetate, by volume relative to the total volume of the composition.

7. Composition according to any one of the preceding claims, characterized in that it comprises at most 20% of a compound selected from dimethyl 2-methylglutarate, 2-methyltetrahydrofuran, ethyl acetate, cyclopentyl methyl ether, dithoxymethane, dimethyl carbonate, dimethyl succinate, benzyl alcohol, dimethyl adipate, glycerol triacetate or any mixture thereof, by volume relative to the total volume of the composition.

8. A method for cleaning equipment for preparing and / or applying solvent-based paints or other coatings, characterized in that it comprises at least one step of cleaning said equipment using a solvent composition as defined in any one of claims 1 to 7.

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