Water-Based Aerosol Paint

Abstract

The invention relates to a water based paint composition to be used in a pressurized and sealed aerosol can and which composition contains A) up to 24% w/w of propellant gas which is dimethyl ether (DME); B) up to 76% w/w of coating material, consisting nonvolatile content in the range of 65-95% w/w and volatile content in the range of 5-35% w/w;which volatile content contains water up to 0-100% w/w and additives, co-solvents and dispersing agents which comprise altogether of 0-9% w/w of volatile liquids, having 0-10% w/w preferably less than 5% w/w of volatile organic compounds (VOC) provided that the aggregate amount of dimethyl ether (DME) and the volatile organic compounds (VOC) in volatile liquids is such that VOC concentration is below 186 g/l (responding about 24% w/w, calculated as DME). In the present invention the nonvolatile content comprises color pigments and possible fillers in the range of 0-30% w/w, polyurethane modified alkyd resin or alkyd resin in the range of 25-99% w/w preferably in the range of 35-90% w/w and additives up to 9% w/w, which resin is present as an emulsified dispersion in water miscible solvent comprising water and dimethyl ether (DME).

Claims

1. A water based paint composition to be used in a pressurized and sealed aerosol can, comprising: A) up to 24% w/w of propellant gas which is dimethyl ether (DME); B) up to 76% w/w of a coating material, consisting of a nonvolatile content in a range of 65-95% w/w and a volatile content in a range of 5-35% w/w; which volatile content contains water up to 0-100% w/w and additives, co-solvents and dispersing agents which comprise altogether of 0-9% w/w of volatile liquids, having 0-10% w/w, preferably less than 5% w/w of volatile organic compounds (VOC), provided that an aggregate amount of dimethyl ether (DME) and the volatile organic compounds (VOC) in volatile liquids, is such, that a VOC concentration is below 186 g/l (responding about 24% w/w, calculated as DME) and which nonvolatile content comprises color pigments and possible fillers in a range of 0-30% w/w, an acryl resin, an acryl/alkyd-resin, a polyurethane modified alkyd resin or an alkyd resin in a range of 25-99% w/w, preferably in a range of 35-90% w/w and additives up to 9% w/w, which resin, is present as an emulsified dispersion in a water miscible solvent comprising water and dimethyl ether (DME).

2. The water based aerosol paint composition of claim 1, wherein the composition consists of dimethyl ether (DME) up to 24% w/w, polyurethane modified alkyd resin or alkyd resin in a range of 30-65% w/w, additives and dispersing agents in a range of 0-2% w/w, color pigments, fillers and mattening agents in a range of 0-20% w/w and the rest being water.

3. The water based aerosol paint composition of claim 1, wherein the composition consists of dimethyl ether (DME) up to 24% w/w, polyurethane modified alkyd resin or alkyd resin in a range of 30-65% w/w, additives and dispersing agents in a range of 0-2% w/w and the rest being water.

4. The water based aerosol paint composition of claim 1, wherein the dry weight is in a range of 40-45% of the nonvolatile content and 30-37%, preferably 32-35% w/w from a total weight of the aerosol paint.

5. The water based aerosol paint of claim 2, wherein pigments contain TiO.sub.2.

6. The water based aerosol paint composition of claim 1, wherein the polyurethane modified alkyd resin or alkyd resin is at least one resin selected from the groups a)-f) defined as: a) saponified/neutralized short oil alkyd which is water dilutable/emulsifiable having less than 40% of fatty acids, b) saponified/neutralized medium oil alkyd which is water dilutable/emulsifiable having 40-60% of fatty acids, c) emulsified/dispersed short oil alkyd having less than 40% of fatty acids, d) emulsified/dispersed medium oil alkyd having 40-60% of fatty acids, e) emulsified/dispersed polyurethane modified alkyd being chained with mid oil having 40-60% of fatty acids, f) emulsified/dispersed polyurethane modified alkyd being chained with short oil having less than 40% of fatty acids.

7. The water based aerosol paint composition of claim 1, wherein the water based solvent consists of water and dimethyl ether.

8. The water based aerosol paint composition of claim 1, wherein the water based solvent does not contain any organic co-solvent.

9. A method for preparing a water based paint with a high dry weight and a lowered amount of volatile organic compounds (VOC) into a pressurized and sealed aerosol can, comprising: filling an aerosol can with the coating material defined in claim 1, closing the can, and filling the closed can with liquefied propellant dimethyl ether (DME).

10. The method of claim 9, wherein a filling volume of the can is either 400 ml or 675 ml.

11. A method for preparing a water based aerosol paint with a high dry weight and a lowered amount of volatile organic compounds (VOC) comprising: filling the aerosol can with a coating material comprising resin in a range of 50-65% w/w, additives and dispersing agents in a range of 0-2% w/w, color pigments, fillers in a range of 0-20% w/w the rest of the coating material being water, and then filling the closed can with liquefied propellant dimethyl ether (DME) wherein the resin is an alkyd resin or a urethane modified alkyd resin selected from groups (a)-(f) defined as: a) saponified/neutralized short oil alkyd which is water dilutable/emulsifiable having less than 40% of fatty acids, b) saponified/neutralized medium oil alkyd which is water dilutable/emulsifiable having 40-60% of fatty acids, c) emulsified/dispersed short oil alkyd having less than 40% of fatty acids, d) emulsified/dispersed medium oil alkyd having 40-60% of fatty acids, e) emulsified/dispersed polyurethane modified alkyd being chained with mid oil and having 40-60% of fatty acids and f) emulsified/dispersed polyurethane modified alkyd being chained with short oil and having less than 40% of fatty acids, wherein the the quality of liquid additives, dispersing agents, color pigments, fillers and mattening agents and their amount is selected so, that their aggregate amount of volatile organic compounds will make less than 3%, and the amount of DME to be added into can is less than 24% w/w of the total amount of the water based aerosol paint.

12. The method defined in claim 11, wherein the resin is selected so that shelf life of the water based aerosol paint is several months.

13. The water based aerosol paint composition of claim 1, wherein the resin is an acrylic dispersion, an acrylic emulsion or an acryl/alkyd dispersion.

14. The water based aerosol paint composition of claim 1, wherein the resin selected from the group consisting of the acryl resin, the acryl/alkyd-resin, the polyurethane modified alkyd resin or the alkyd resin does not contain any organic co-solvent.

Description

EXAMPLES FROM COMPOSITIONS

[0131] Paint Compositions for Aerosol Cans

[0132] Following compositions were prepared into an aerosol can by filling an aerosol can with the coating material then closing the can. The closed can was filled with liquefied propellant dimethyl ether (DME). The filling volume of the can was either 400 ml or 675 ml. In any of the given examples can be used all binders given in table 1.

Example 1

[0133] High Gloss Top Coat

TABLE-US-00009 Ingredients % w/w Necowell 4300 60.00 Dispersing aid 0.40 Drier 0.06 Defoamer 0.30 color pastes 10.00 Thickener 0.25 Aerosil 200 (SiO2 fumed) 0.50 Water 6.49 Dimethyl ether 22.00 Total 100.00

[0134] Instead of Necowell 4300 also other binders mentioned in table 1 can be used.

Example 2

[0135] Anti Rust Primer

TABLE-US-00010 Ingredient % w/w Synaqua 4804 53.40 Dispersing aid 0.60 Defoamer 0.30 Iron Oxyde RED paste 8.00 Calcium modified silica gel 5.00 Bentonite 0.60 thickener 0.16 Water 3.50 dimethyl ether 27.00 Total 100.00

[0136] Instead of Synaqua 4804 also other binders mentioned in table 1 can be used.

Example 3

[0137] Clear Top Coat

TABLE-US-00011 Ingredient % w/w Worleesol E330W 57.00 Defoamer 0.30 Thickener 0.35 Flow/slip additive 0.10 Flow/slip additive 20.25 Dimethyl ether 22.00 Total 100.00

[0138] Instead of binder Worleesol E330W can also be used WorleeSol NW 410. Also other binders mentioned in table 1 can be used.

Example 4

[0139] Fast Drying Color High Gloss Top Coat with Excellent Anti Corrosion Proportions

TABLE-US-00012 Ingredient % w/w Worleesol E927W 25.00 Domalkyd 0545 40 Wa or Necowel 586 N 30.00 dispersing agent 0.25 defoamer 0.20 flow/slip additive 0.18 thickner (newtonian) 0.10 thickner (tixothrope) 0.16 mix of collar paste's 10.00 Water 11.11 Dimethyl ether 23.00 Total 100.00

[0140] Instead of Worleesol E927W and Domalkyd 0545 40 Wa or Necowel 586 N also other binders mentioned in table 1 can be used.

Example 5

[0141] A typical water-based aerosol base paint of the invention comprises polyurethane-modified resin 80-100 g (binder), water 100-150 g, various additives 2-11 g and dimethyl ether (DME) 75-95 g, packed for example in an aerosol bottle having a filling volume of 400 ml.

[0142] One typical ready-to-use aerosol base paint of the invention, present in a pressurized aerosol bottle with a filling volume of 400 ml, was prepared as follows: [0143] the polyurethane-modified resin and additives were dispensed into an aerosol bottle; [0144] the propellant (DME) was added into the aerosol bottle and the bottle was sealed to become airtight.

[0145] Thus, the pressurized aerosol bottle having a filling volume of 400 ml contained the following aerosol base paint components in liquid phase:

TABLE-US-00013 Ingredient amount/g amount/w-% Polyurethane-modified alkyd resin 92.7 30.1 Flow promoter (Capston) 0.8 0.2 Pigment stabilizer (Dextrol) 0.9 0.3 Thickener (Rheolate) 1.8 0.6 Drying agent (Additol) 3.3 1.1 Drying accelerator 2.3 0.7 Monoethanolamine (corrosion inhibitor) 0.8 0.2 Water 121.5 39.5 DME (dimethyl ether) 83.6 27.2 Total 307.0 100.0

[0146] The density of this aerosol base paint was about 1 g/cm.sup.3, whereby the volume occupied by the liquid phase of the aerosol bottle's filling volume (400 ml) was about 300 ml.

[0147] Polyurethane resin contains water so as to have a dry matter content of 10-60%. Above is given the proportion of dry polyurethane resin.

[0148] Such an aerosol base paint is combustible as such, but have a high binder content (about 30% by weight) and low amount of DME (27% by weight) and can be used for preparing any of the non-flammable paint compositions aerosol in an aerosol can.

[0149] This aerosol base paint is compatible with most of the commercial toning equipment for water-based paints, i.e. it can have a pigment (coloring paste) dispensed therein in a mechanized manner with dispensing devices having a dosing accuracy of 0.1-0.2 ml.

[0150] This aerosol base paint makes it possible to provide a paint coating with any desired gloss level (matte, semi-gloss, glossy)

[0151] One and the same aerosol base paint lends itself to being toned for a precisely desired tint for example with the RAL color matching system (168 color tones) or with the NCS color tone system (1668 color tones).

[0152] Instead of polyurethane-modified alkyd, it is also possible to use alkyd, epoxy-modified alkyd, styrene-butadiene emulsions/dispersions.

Example 6

[0153] A Base Paint for Preparing a Non-Flammable Paint into an Aerosol Can:

[0154] First aerosol base paint modified in terms of the amount of alkyd resin

TABLE-US-00014 Ingredient amount/g amount/w-% Polyurethane-modified alkyd resin 67.7 22.0 Flow promoter (Capston) 0.8 0.2 Color pigment stabilizer (Dextrol) 0.9 0.3 Thickener (Rheolate) 1.8 0.6 Drying agent (Additol) 3.3 1.1 Drying accelerator 2.3 0.7 Monoethanolamine (corrosion inhibitor) 0.8 0.2 Water 146.5 47.6 DME 83.6 27.2 Total 307.0 100.0

[0155] In the aerosol base paint of example 1, having been packed into an aerosol bottle with a filling volume of 400 ml, the amount of alkyd resin was modified according to which components were added from a filling cup of 100 ml into the aerosol base paint present in the aerosol bottle. The filling cup was again functionally in communication with a toning and dispensing device whose minimum dosing amount was 0.1 ml of coloring paste.

[0156] The first aerosol base paint, which was modified in terms of the amount of alkyd resin, had been modified in such a way that it could be supplemented from the filling cup of a toning and dispensing device with a coloring paste in the amount of 1-35 ml corresponding to each color tone recipe, as well as with a binder and water 50 ml in total (50% by volume of water, 50% by volume of polyurethane-modified alkyd resin). Thereby is obtained an aerosol paint toned to readiness, the space occupied thereby being 350-400 ml of the aerosol bottle with a filling volume of 400 ml.

Example 7

[0157] Second Aerosol Base Paint Modified in Terms of the Amount of Alkyd Resin:

TABLE-US-00015 Ingredient amount/g amount/w-% Polyurethane-modified alkyd resin 42.7 13.9 Flow promoter (Capston) 0.8 0.2 Color pigment stabilizer (Dextrol) 0.9 0.3 Thickener (Rheolate) 1.8 0.6 Drying agent (Additol) 3.3 1.1 Drying accelerator 2.3 0.7 Monoethanolamine (corrosion inhibitor) 0.8 0.2 Water 171.5 55.8 DME 83.6 27.2 Total 307.0 100.0

[0158] In the second modified aerosol base paint, the amount of alkyd resin in the aerosol base paint of example 1 had been changed in such a way that it could be supplemented from a filling cup of the toning and dispensing device with a coloring paste in the amount of 1-35 ml corresponding to each color tone recipe, and with 50 ml of water. Thereby is obtained an aerosol paint toned to readiness, the space occupied thereby being 350-400 ml of the aerosol bottle with a filling volume of 400 ml.

Examples 8A and 8B

Example 8A

[0159] The aerosol base paint of example 5 was modified to get a white base paint and it was packed into an aerosol can with a filling volume of 400 ml and then toned in a mechanized manner with a commercial dispensing machine (see FIG. 1) whose minimum dispensing amount was 0.1 ml of color paste compound.

[0160] The color paste mixture was dispensed into a filling cup of the dispensing machine in an amount 1-50 ml corresponding to color tone recipe, and then into the same filling cup was added 40 ml of binder (polyurethane-modified alkyd resin). Thereby was obtained an aerosol paint toned to readiness for use, the space occupied thereby being 350-400 ml of the aerosol can with a filling volume of 400 ml.

[0161] Part A: Filled Aerosol can

TABLE-US-00016 White base paint 247 g (185 ml) DME (dimethyl ether) 73 g (110 ml)

[0162] Part B: Filling Cup, Added to Aerosol can of Part A

TABLE-US-00017 Domalkyd 0545 40 Wa or Necowel 586 N (binder) 40 g (40% w/w emulsion in water) Color paste mixture 20-50 g (20-50 ml)

[0163] Parts a+B Combined, Main Components of the Formed Aerosol Paint

TABLE-US-00018 Binder (Domalkyd 0545 40 Wa or Necowel 586 N) 31% w/w Water 10% w/w DME 19% w/w TiO.sub.2 25% w/w Other pigments 5-12% w/w Additives 5-12% w/w, wherein each of the additive is added 0.1-1.5% w/w

[0164] White base paint composition and its volatile organic compounds Polyurethane modified alkyd emulsion [0165] Domalkyd 0545 40 Wa or Necowel 586 N 40% w/w in water, VOC Free

[0166] Siccatief 0.22% w/w [0167] Drier

[0168] Dextrol OC-180 [0169] dispersing agent)

[0170] TiO.sub.2

[0171] Capstone SF 65 [0172] surface tension modifier, VOC free

[0173] BYk 349 [0174] surface tension modifier

[0175] Rheolate 310 [0176] rheology modifier, VOC free

[0177] Diosperbyk 199 [0178] Wetting and dispersive agent, Voc free, pigment stabilizer

[0179] AMP [0180] pH modifier

[0181] Water (demineralized)

[0182] Acemat Ok 520 [0183] solid matting agent

[0184] As can be seen above none of the additives, binder or pigments contains any volatile organic compounds (VOC). The only VOC-source was DME having weight of 19% w/w of the total weight of the readymade aerosol paint in the can (400 ml). The VOC-content of this aerosol paint is 19% and it was nonflammable in a subsequent test.

Example 8B

[0185] The aerosol base paint of example 1 was modified to get a clear base paint and it was packed into an aerosol can with a filling volume of 400 ml and then toned in a mechanized manner with a commercial dispensing machine (see FIG. 1) whose minimum dispensing amount was 0.1 ml of color paste compound.

[0186] The color paste mixture was dispensed into a filling cup of the dispensing machine in an amount 1-50 ml corresponding to color tone recipe, and then into the same filling cup was added 40 ml of binder (polyurethane-modified alkyd resin). Thereby was obtained an aerosol paint toned to readiness for use, the space occupied thereby being 350-400 ml of the aerosol can with a filling volume of 400 ml.

[0187] Part A: Filled Aerosol can

TABLE-US-00019 Binder mix clear 185 g (185 ml) DME (dimethyl ether) 73 g (110 ml)

[0188] Part B: Filling Cup, Added to Aerosol can of Part A

TABLE-US-00020 Domalkyd 0545 40 Wa or Necowel 586 N (binder) 40 g (40% w/w emulsion in water) Color paste mixture 20-50 g (20-50 ml)

[0189] Parts a+B Combined, Main Components of the Formed Aerosol Paint

TABLE-US-00021 Binder (Domalkyd 0545 40 Wa or Necowel 586 N) 48% w/w Water 6% w/w DME 21% w/w Pigments 7-15% w/w Additives 5-10% w/w, wherein each of the additive is added 0.1-1.5% w/w

[0190] Clear binder mix base paint composition and its volatile organic compounds Polyurethane modified alkyd emulsion [0191] Domalkyd 0545 40 Wa or Necowel 586 N 40% w/w in water, VOC Free

[0192] Borchi oxy coat, Voc free [0193] Drier

[0194] Dextrol OC-180 [0195] dispersing agent)

[0196] TiO.sub.2

[0197] Capstone SF 65 [0198] surface tension modifier, VOC free

[0199] BYk 349 [0200] surface tension modifier

[0201] Rheolate 310 [0202] rheology modifier, VOC free

[0203] Diosperbyk 199 [0204] Wetting and dispersive agent, Voc free, pigment stabilizer

[0205] AMP [0206] pH modifier

[0207] Water (demineralized)

[0208] As can be seen above none of the additives, binder or pigments contains any volatile organic compounds (VOC). The only VOC-source was DME having weight of 19% w/w of the total weight of the readymade aerosol paint in the can (400 ml). The VOC-content of this aerosol paint is 21% w/w and the paint was non-flammable in a subsequent test.

Example 8

[0209] Comparison Tests for Ageing of Aerosol Paints

[0210] General

[0211] The spray pattern delivered from an aerosol can is a combination of the content of the can proportions, being the amount of liquefied propellant, the pressure, viscosity and of course how fine are the solid particles that have to be transported through the valve and the actuator.

[0212] As an indication the diameter of the openings in the valve and actuator during the spraying are between 0.1 mm to 0.5 mm.

[0213] This means if paint in the can starts to flocculate or is the binder gets attacked by the propellant (DME) and cloaks together this will have a direct impact on the spray result. This can lead to solid particles disturbing the wet film and being visible in the dry film until totally blocking of the valve and actuator.

[0214] Aging tests have been done with the formulations 1-3.

[0215] Formulation 1

[0216] Colored top coat based on mix of polyurethane modified short and medium oil alkyd emulsion (composition according to invention)

TABLE-US-00022 Ingredient amount/w-% Resin 1 Worleesol E927W 25.00 Resin 2 Domalkyd 0545 40 Wa or Necowel 586 N 30.00 dispersing agent Byk 191 0.25 defoamer Byk 015 0.20 flow/slip additive tego glide 110 0.18 thickener (Tixothrope)Tafigel pur 60 0.10 thickener (Tixothrope) Byk 525 0.16 color paste mixture 10.00 water 11.11 Dimethyl ether 12.00 Total 100.00

[0217] Formulation 3I: Acrylic Dispersion Based Colored Top Coat

TABLE-US-00023 Ingredient % w/w EPS 294 (405 w/w in water) 35.00 thickener Rheolate 310 0.40 Tego glide 110 0.30 Bentone SD2 0.13 Color pastes 8.00 Texanol (solvent no VOC) 3-pentanediol,2,2,4-trimethyl-monoisobutyrate) 4.00 water 17.17 Dimethyl ether (DME) 35.00 Total 100.00

[0218] Formulation 3I

[0219] Clear Acrylic Varnish:

TABLE-US-00024 Ingredient % w/w Joncryl 538 (acrylic dispersion) 32.40 Joncryl 683 (low mol weight acryl 98% in solvent) 9.00 diethyleneglycol monobutylether (non-flammable 4.00 but it will burn. UEL 6.2 LEL 0.9% in air) Isopropanol 3.00 Defoamer byk 015 0.30 Acemat 520 (hydrophobic fumed silica) 0.40 Thickener DSX 3290 0.55 water 10.35 Dimethyl ether 40.00 Total 100.00

[0220] Results

[0221] After aging tests in the oven at 40 C. and 20 C. with intervals of 1 week spray test have been performed.

[0222] Formulation I

[0223] 1 week high gloss good opacity no spray defects Eventually this formulation has a shelf life of app 3 years at 20 C.

[0224] Formulation 2

[0225] 1 week little lower gloss than fresh can at start of the test. opacity ok

[0226] 2 weeks solid particles in the spray interrupting the spray pattern and visible in the wet and dry film.

[0227] 3 weeks after vigorously shaking the shaking balls were free a pray attempt was made but the valve/actuator system was blocked completely. After degassing the can (uncultured with a pin) the paint in the can was observed. It showed total coagulated binder and color pigment.

[0228] Conclusion: not stable, short shelf life

[0229] Formulation 3

[0230] Immediately (timeframe appr. 1 h) after making the can it was impossible to spray for the moment the actuator was pushed down the valve and the actuator blocked completely.

[0231] After degassing the can (uncultured with a pin) the paint in the can was observed. It showed total coagulated binder and color pigment.

[0232] Conclusion: Nor stable, very short shelf life

[0233] Conclusions: Acrylic dispersions (formula 1 and 2) of water-borne aerosol paint do not have enough shelf life, because acrylic resins are incompatible with propellant dimethyl ether (DME). When alkyd polyurethane modified short and medium oil alkyd emulsion were used as resin enough shelf life was achieved.