RU2278884C2 - Composition for coating applying - Google Patents

Abstract

FIELD: coating compositions.

SUBSTANCE: invention relates to composition used for coating applying and comprising polyisocyanate compound, hydroxyl-functional film-forming polymer and nonvolatile branched monoatomic alcohol wherein the aliphatic branched monoatomic alcohol is preferable but long-chain nonvolatile branched monoatomic alcohols are more preferable. This provides preparing compositions for applying coatings that possess the improved indices of fluidity and can be used for preparing coatings with the improved appearance and without the negative effect on other properties. Also, invention relates to the multiple composition fir applying coatings. The multicomponent composition for applying coatings represents the bicomponent composition for applying coatings preferably that comprises the polyisocyanate component in addition to hydroxyl-functional film-forming polymer comprising nonvolatile branched monoatomic alcohol also. Also, invention relates to a method for car finishing comprising applying compositions for applying coating on car and to a method for preparing the multilayer coating.

EFFECT: valuable properties of composition.

30 cl, 1 tbl, 2 ex

Description

Cross reference to related application

This application has a priority date for the filing date of provisional application No. 60/224139, filed August 10, 2000, and European patent application No. EP 00203453.6, filed September 28, 2000.

Prior art

There is a need in the industry to improve the flow characteristics of coating compositions containing polyisocyanate compounds and hydroxyl-functional film-forming polymers and the appearance of coatings formed from such coating compositions, while maintaining other properties of the coating and coating compositions. It was found that the desired improvement can be achieved by using non-volatile branched monohydric alcohols. Particularly suitable are long chain linear monohydric alcohols having 12 or more carbon atoms. Since these monohydric alcohols having 12 or more carbon atoms are generally solid at room temperature, it appears that their use in coating compositions should be limited. It has been found that some long-chain non-volatile branched monohydric alcohols are suitable as additives in coating compositions, in particular in multicomponent (at least bicomponent) coating compositions. This results in coating compositions that have improved flow characteristics and which provide coatings with improved appearance without unacceptable adverse effects on other properties.

Coating compositions comprising a polyisocyanate and a polyol are known, for example, from European Patent Application No. 0219131. This reference also describes the use of such coating compositions for a variety of purposes, including for applying a coating layer to relatively high mass products such as vehicles, machinery in industry and buildings, and machinery in construction.

Fast setting, fast curing coating compositions using high Tg acrylic binders are mentioned, for example, in US Pat. Nos. 5,741,880 and 5,759,631. A combination of hard acrylate with a low viscosity polyol is cited in US 5,286,782. In order to obtain low volatile organic compound coating compositions fast evaporating solvents can be added together with solvents with low photochemistry, such as acetone, methyl acetate and tertiary butyl acetate t. The combination of rapidly evaporating solvents with acrylic binders can lead to poor flow and appearance. In order to improve flowability and appearance, large quantities of low viscosity polyols are sometimes added, but they can cause slower cure and worse setting.

US 4,235,766 describes a coating composition comprising an organic polyhydroxy compound and an organic polyisocyanate. The coating composition further comprises 2-methyl-2-propanol and / or 2-methyl-2-butanol. These monohydric alcohols are volatile compounds. The disadvantage associated with the use of volatile compounds is that there is no control over how much of the compound will be introduced into the coating after the coating composition is applied, and how much it will evaporate and contribute to the volatile organic substances of the composition for coating.

SUMMARY OF THE INVENTION

The present invention relates to a coating composition comprising a polyisocyanate compound, a hydroxyl-functional film-forming polymer and a non-volatile branched monohydric alcohol. An aliphatic branched monohydric alcohol is preferred.

The present invention also relates to a multicomponent coating composition. The multicomponent coating composition is preferably a two-component coating composition comprising a polyisocyanate component and a hydroxyl-functional component, wherein the hydroxyl-functional component in addition to the hydroxyl-functional film-forming polymer also contains a non-volatile branched monohydric alcohol. The non-volatile branched monohydric alcohol can be mixed with the hydroxyl-functional film-forming polymer or it can be added during the preparation of the hydroxyl-functional film-forming polymer.

DETAILED DESCRIPTION OF THE INVENTION

Any nonvolatile, branched, aliphatic monohydric alcohol may be used in the present invention. The non-volatile branched aliphatic monohydric alcohol, preferably used in the present invention, has at least 12 carbon atoms, more preferably at least 16 carbon atoms. You can also use a mixture of non-volatile branched monohydric alcohols having at least an average of 12 carbon atoms, more preferably at least an average of 16 carbon atoms. It is preferable to use Gerbe alcohol or a mixture of Gerbe alcohols, more preferably a Gerbe alcohol having at least 12 carbon atoms (or a mixture of Gerbe alcohols having at least 12 carbon atoms on average), most preferably at least 16 carbon atoms (or a mixture of Gerbe alcohols having at least 16 carbon atoms on average). Gerbe alcohols are branched primary alcohols that are linear and they contain two carbon chains, and the branch point is always in the position of the second carbon atom.

The hydroxyl-functional film-forming polymer is preferably characterized by a hydroxyl number in the range of 50 to 300 mg KOH / g based on the solid phase, more preferably in the range of 70 to 200 mg KOH / g.

The number average molecular weight of the polymer is preferably below 6000 according to gel permeation chromatography measurements using polystyrene as a standard, more preferably below 4500. The degree of molecular dispersion, that is, the ratio of Mw to Mn, is preferably in the range from 1.1 to 5, with particularly preferred is a range from 1.1 to 3. The acid number of the polymer is preferably in the range from 0 to 50 mg KOH / g based on the solid phase. The Tg of the acrylic polyol is preferably greater than 25 ° C, more preferably higher than 40 ° C, most preferably in the range of 60 to 110 ° C.

Hydroxyl-functional film-forming polymers include polyesters, polyacrylates, polyvinyl, polyurethanes, polycarbonates or polyamides as a non-limiting example, and preferably it is an acrylic polyol. Acrylic polyol is obtained from hydroxy-functional acrylic monomers such as hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, other acrylic monomers such as (meth) acrylic acid, methyl (meth) acrylate, n- butyl (meth) acrylate, tert-butyl (meth) acrylate, isobornyl (meth) acrylate, trimethylcyclohexyl (meth) acrylate, and optionally in combination with a vinyl derivative such as styrene and the like, or mixtures thereof, where the terms (meth) acrylate and (meth) acrylic acid refer to both methacrylate and acrylate, well as methacrylic acid and acrylic acid, respectively. The acrylic polyol is prepared according to commonly used methods, for example, by slowly adding suitable monomers to a solution of a suitable polymerization initiator, such as azole peroxy initiator, in a solvent.

In the case where a non-volatile branched monohydric alcohol is added during the preparation of the hydroxyl-functional film-forming polymer, preferably during the production of an acrylic polyol, the monohydric alcohol is preferably charged into the reaction vessel together with the solvent before the polymerization process begins.

The mass ratio of the amount of non-volatile branched monohydric alcohol to the amount of solid hydroxyl-functional film-forming polymer is preferably in the range from 1:99 to 50:50, more preferably from 5:95 to 25:75.

Polyisocyanates suitable for the present invention as polyisocyanate compounds and suitable for polyisocyanate components include polyisocyanates having two or more, preferably two to four isocyanate groups. Non-limiting examples of polyisocyanates suitable for the present invention include toluene diisocyanate, methylene bis (4-cyclohexyl isocyanate), isophorone diisocyanate and its isocyanurate or adducts, hexamethylene diisocyanate and its isocyanurate, biuret, allophanate and uretdione and meta-tetramethylxylylene diisocyanate and the adduct thereof with trimethylolpropane.

The polyisocyanate compound is used in such an amount that the ratio of the number of isocyanate groups to the total number of hydroxyl groups in the coating composition is preferably in the range from 0.8 to 2.

The solvent may be part of a hydroxyl functional component, a polyisocyanate component, and / or it may be a separate diluent. More specifically, in a multi-component system, a diluent may be one of the components. In a multicomponent system comprising a polyisocyanate component, a hydroxyl functional component and a third component, the diluent may be a third component.

The coating composition may also contain catalysts for the reaction between isocyanate and hydroxyl, such as dibutyltin dilaurate, triethylamine and the like. Coating compositions may also contain pigments. Inorganic as well as organic pigments may be used. In addition, the composition may contain commonly used additives, such as stabilizers, surfactants, fillers, ultraviolet absorbers, catalyst blocking agents, antioxidants, dispersant pigments, flow improvers, flow control additives, leveling agents means and solvents. The solvent can be any solvent known in the art, that is, it can be aliphatic and / or aromatic hydrocarbons. Examples include Solvesso® 100, Exxate 600, toluene, xylene, 4-chlorobenzotrifluoride, butanol, isopropanol, butyl acetate, tert-butyl acetate, ethyl acetate, methyl acetate, methoxypropyl acetate, n-butyl propionate, ethoxyethyl ethyl ketone, methyl ethyl ketobutyl, ether-based alcohol and ether-based ester or a mixture of any of these compounds.

The coating composition preferably contains less than 550 g / l volatile organic solvent, based on the entire composition, more preferably less than 500 g / l, most preferably less than 480 g / l.

The present invention also relates to a multicomponent coating composition. Such a multicomponent coating composition contains at least two components, i.e. a hydroxyl-functional component and a polyisocyanate component. The multicomponent coating composition preferably contains three components, the third component included, that is, the diluent, includes solvents to impart a viscosity coating composition suitable for spray application.

The coating composition of the present invention can be applied to any substrate. The substrate may be, for example, metal, plastic, wood, glass, ceramic or a layer of another coating. The other coating layer may be formed from the coating composition of the present invention, or it may be another coating composition. The coating compositions of the present invention are particularly suitable for use as unpigmented coatings, primers, pigmented coating layers of coatings, primers and fillers. Coating compositions can be applied by commonly used means, such as a spray gun, brush or roller, with spraying preferred. Curing temperatures are preferably in the range of 0 to 80 ° C., and more preferably in the range of 20 to 60 ° C. The compositions are particularly suitable for the preparation of coated metal substrates, such as those in the re-coating industry, in particular in the body shop for the repair of motor vehicles and vehicles, and in the coating of large vehicles, such as trains, trucks cars, buses and planes.

It is preferable to use the coating composition of the present invention as an unpigmented coating. Unpigmented coatings are required to be highly transparent and should adhere well to the primer layer. In addition, it is required that the non-pigmented coating does not change the aesthetic aspect of the primer coating due to the passage of one coating layer to another, that is, as a result of discoloration of the primer coating by solvents present in the unpigmented coating composition, or as a result of yellowing of the non-pigmented coating due to exposure to the outside premises. The non-pigmented coating based on the coating composition of the present invention does not have these disadvantages.

Accordingly, the present invention also relates to a method for producing a multilayer coating comprising the steps of applying to an optionally coated substrate a primer composition, optionally curing the primer, applying a non-pigmented coating composition according to the present invention over the primer, and curing the multilayer coating.

In the event that the coating composition is a non-pigmented coating, the primer coating may be a commonly used primer coating known in the art for coating. Examples are solvent-based primers, for example Autobase® from Akzo Nobel Coatings, and water-based primers, for example Autowave® from Akzo Nobel Coatings. In addition, the primer coating may contain pigments (coloring pigments, metallic luster pigments and / or mother-of-pearl pigments), waxes, solvents, flow improvers, a neutralizing agent and antifoam agents. Primers with a high solids content can also be used. Their basis, for example, are polyols, imines and isocyanates. The non-pigmented coating composition is then applied to the surface of the primer coating and then cured. An intermediate curing step for the primer may be introduced.

The invention will be further illustrated by the following specific, but not limiting examples.

EXAMPLES

Example 1

Acrylic Polyol 1

Acrylic polyol 1 was obtained by loading into a 5-liter 4-necked round-bottom flask equipped with a stirrer, a refrigerator, a heating jacket, a thermocouple with a temperature regulator, inputs for nitrogen and reagents, 700 g of n-butyl propionate. The solvent in a nitrogen atmosphere was heated to a distillation temperature of 145-150 ° C.

When the temperature reached a distillation temperature of 145-150 ° C and stabilized at this value, the following mixture was introduced into the flask for 180 minutes above the liquid surface: 600 g of styrene, 800 g of tert-butyl methacrylate, 200 g of n-butyl methacrylate, 400 g of 2-hydroxyethyl methacrylate and 79 g of tert-butyl peroxy-3,5,5-trimethylhexanoate. During the introduction of this mixture, the reaction temperature was maintained equal to the distillation temperature, conducting the reaction in a nitrogen atmosphere. After completion of the introduction of the line for the introduction of reagents, first washed with 50 g of n-butyl acetate, and then with a mixture with an additive designed to produce residues of monomer consisting of 50 g of n-butyl acetate and 1.0 g of tert-butyl peroxy-3,5,5- trimethylhexanoate. The reaction temperature was maintained at the level of distillation temperature for another hour. Finally, 320 g of n-butyl acetate was added as a diluent.

The resulting solution of acrylic polyol 1 with a high solids content was characterized by a non-volatile component content of 64.3%, a Brookfield viscosity of 3800 cps (25 ° C, a spindle of 4 and 20 revolutions per minute), and a hydroxyl number of 86 , 3 (mg KOH / g calculated on the solid phase). The molecular weight of the polymer was measured using a Waters' Associates gel permeation chromatography (GPC) device and Phenomenex polystyrene standards. The high solid phase acrylic polyol 1 was characterized by a Mn value of 3020, an Mw value of 8134, a dispersion degree, D of 2.69, and a theoretical Tg of 87 °.

Hydroxyl-functional component 1

The hydroxyl-functional component 1 was obtained by mixing

74.3 g of the above acrylic polyol 1,

4.2 g of Gerberan alcohol having 18 carbon atoms (ISOFOL® 18T from CONDEA Chemie GmbH, Hamburg, Germany),

8.0 g of butyl acetate,

8.8 g of acetone

0.1 g of dibutyltin dilaurate (10% in butyl acetate),

1.7 g of a flow improver (Byk 310, Byk Chemie, 10% in xylene),

1.4 g of a UV stabilizer (Tinuvin 292, from Ciba) and

1.4 g of a UV stabilizer (Tinuvin 1130, from Ciba).

Polyisocyanate component 1

To obtain the polyisocyanate component 1, the following compounds were mixed:

55 g of isocyanurate hexanediisocyanate (90% in butyl acetate, Desmodur N3390, from Bayer),

16.2 g of xylene,

16.8 g of methoxypropyl acetate and

11.4 g of butyl acetate.

Thinner 1

To obtain diluent 1, the following compounds were mixed:

22.8 g of acetone

13.5 g of methoxypropyl acetate and

63.7 g Exxate 600.

Preparation and application of a coating composition 1.

In order to obtain a non-pigmented coating layer of the coating from the coating composition of the present invention, a hydroxyl functional component 1, a polyisocyanate component 1 and a diluent 1 were mixed with a volume ratio of 100: 50: 30. In the first step, the polyisocyanate component 1 was mixed diluent 1. In a second step, a hydroxy-functional component was added 1. The non-pigmented coating layer was characterized by a volatile organic matter content of 4.0 lb / g allon excluding acetone. The ratio of crosslinkable components of NCO: OH was 1.4.

To evaluate the present invention, primers in the form of a Colorbuild® sealant (from Akzo Nobel Coatings) were applied to the test panels, then Autobase® (Akzo Nobel Coatings) was spray applied. The unpigmented coating layer obtained above was sprayed onto the thus prepared panels. The properties of the composition for applying the unpigmented coating layer of the coating and the resulting coating are shown in table 1.

Comparative Examples A and B

In order to demonstrate the improved flowability and appearance obtained by using the present invention, comparative example A was used, which was a repetition of example 1 except that a non-volatile branched aliphatic monohydric alcohol was not used; that is, no alcohol was present for the coat of arms. In comparative example B, a non-volatile branched aliphatic monohydric alcohol was replaced with a Desmophen 670-80% solution in Bayer polyester polyol butyl acetate from Bayer.

Comparative Example A

Hydroxyl Functional Component A

The hydroxyl-functional component A was obtained by mixing

80.8 g of the acrylic polyol 1 obtained above,

5.7 g of butyl acetate

8.8 g of acetone

0.1 g of dibutyltin dilaurate (10% in butyl acetate),

1.7 g of a flow improver (10% Byk 310, byk Chemie, in xylene),

1.4 g of a UV stabilizer (Tinuvin 292, from Ciba) and

1.4 g of a UV stabilizer (Tinuvin 1130, from Ciba).

Composition for coating A and application

Coating composition A was prepared and applied in a manner identical to that of Example 1, except that the hydroxyl-functional component A was used. The content of volatile organic substances was 4.0 lb / gallon, excluding acetone. The ratio of crosslinkable components was 1.4. The properties of the coating composition of comparative example A and the resulting coating are shown in table 1.

Comparative Example B

Hydroxyl Functional Component B

The hydroxyl-functional component B was obtained by mixing

74.3 g of the acrylic polyol 1 obtained above (70% in methylamyl ketone),

5.3 g of Desmophen 670 (80% in butyl acetate),

6.9 g of butyl acetate,

8.8 g of acetone

0.1 g of dibutyltin dilaurate (10% in butyl acetate),

1.7 g of a flow improver (10% Byk 310, byk Chemie, in xylene),

1.4 g of a UV stabilizer (Tinuvin 292, from Ciba) and

1.4 g of a UV stabilizer (Tinuvin 1130, from Ciba).

Composition for coating and application

Coating composition B was prepared and applied in a manner identical to that of Example 1, except that the hydroxyl-functional component B was used. The volatile organic content was 4.0 lb / gallon, excluding acetone. The ratio of crosslinkable components was 1.4. The properties of the coating composition of comparative example B are shown in table 1.

Table 1 Property Method (unit) Example 1 Comparative Example A Comparative Example B Viscosity at 70 ° F DC4 (second) 13.9 15.7 15.1 Viscosity after 2 hours DC4 (second) 23,2 20.3 21,2 Drying period until the coated substrate can be picked up at 60 ° C Hand (minute) 36 29th 35 Hardness, 1 day By Perseus (second) 62 59 52 Hardness, 7 days By Perseus (second) 151 159 124 DOI (Image Clarity) (7 days) 85 75 75 Appearance Visually (3 people) 8.5 6.5 6.7 Shortwave tension S Wave Scan (Byk) 4.9 10.3 10.3 Long wave tension L Wave Scan (Byk) 31.1 33,2 34.1

As the data shown in table 1 show, the use of a non-volatile branched monohydric alcohol allows for improved coating performance and appearance for the coating composition of the present invention while maintaining other desirable properties.

Example 2

Acrylic Polyol 2

Acrylic polyol 2 was obtained by loading into a 5-liter 4-necked round-bottom flask equipped with a stirrer, a refrigerator, a heating jacket, a thermocouple with a temperature regulator, inputs for nitrogen and reagents, 200 g of n-butyl propionate and 500 g of Gerbe alcohol, i.e. Isofol® 18T. The mixture was heated to 150 ° C. under a nitrogen atmosphere.

When the temperature reached 150 ° C, the following mixture was introduced into the flask over 180 minutes above the surface of the liquid: 1000 g of styrene, 200 g of tert-butyl methacrylate, 400 g of n-butyl methacrylate, 400 g of 2-hydroxyethyl methacrylate and 98 g of tert-butyl peroxy-3. 5,5-trimethylhexanoate. During the introduction of this mixture, the reaction temperature was maintained equal to the distillation temperature, conducting the reaction in a nitrogen atmosphere. After completion of the introduction of the line for the introduction of reagents, first washed with 50 g of tert-butyl acetate, and then with a mixture with an additive designed to produce residues of the monomer consisting of 50 g of tert-butyl acetate and 1.0 g of tert-butyl peroxy-3,5,5- trimethylhexanoate. The reaction temperature was maintained at 150 ° C for another hour. Finally, 814 g of tert-butyl acetate was added as a diluent.

The resulting solution of acrylic polyol 2 with a high solids content was characterized by a non-volatile component content of 70.1%, a Brookfield viscosity of 1800 cPs at 65% (dilution with tert-butyl acetate at 25 ° C, spindle 4 and 20 rpm ), and a hydroxyl number of 112.7 (mg KOH / g, calculated on the solid phase). The molecular weight of the polymer was measured using a Waters' Associates gel permeation chromatography (GPC) device and Phenomenex polystyrene standards. Acrylic polyol 2 with a high solids content was characterized by a Mn value of 3750, a Mw value of 8430, a degree of dispersion, D of 2.2.

Hydroxyl-functional component 2

The hydroxyl-functional component 2 was obtained by mixing

67.9 g of the acrylic polyol 2 obtained above,

10.0 g of ethoxyethyl propionate,

13.8 g of acetone

0.1 g of dibutyltin dilaurate (10% in butyl acetate),

1.7 g of a flow improver (10% Byk 310, byk Chemie, in xylene),

1.4 g of a UV stabilizer (Tinuvin 292, from Ciba) and

1.4 g of a UV stabilizer (Tinuvin 1130, from Ciba).

Hydroxyl Functional Component 3

The hydroxyl-functional component 3 was obtained by mixing

68.8 g of the above acrylic polyol 1,

12.5 g of Gerbe alcohol, i.e.Isofol® 18T,

3.5 g of ethoxyethyl propionate,

12 g of acetone

0.2 g of dibutyltin dilaurate (10% in butyl acetate),

0.4 g of a flow improver (10% Byk 310, from Byk Chemie, in xylene),

1.3 g of a UV stabilizer (Tinuvin 292, from Ciba) and

1.3 g of a UV stabilizer (Tinuvin 1130, from Ciba).

Polyisocyanate Component 2

To obtain a hardener, the following compounds were mixed:

70 g of isocyanurate hexanediisocyanate (Desmodur N3600, from Bayer),

30 g of tert-butyl acetate.

Polyisocyanate component 3

65 g of isocyanurate hexanediisocyanate (Desmodur N3600, from Bayer),

35 g of 4-chlorobenzotrifluoride.

Obtaining and applying compositions for coating 2 and 3

To obtain a non-pigmented coating option 2 from the coating composition of the present invention, a hydroxyl-functional component 2, a polyisocyanate component 2, and a diluent were mixed with a volume ratio of 100: 50: 30. As diluent for coating composition 2, tert-butyl acetate was used. Variant non-pigmented coating 3 was obtained in the same way, except that 4-chlorobenzotrifluoride was used as a diluent. Unpigmented coatings had a volatile organic content of 2.0 lbs / gallon, excluding free solvents, with a spray viscosity of 13-14 seconds according to DC4.

To evaluate the present invention, primers in the form of a Colorbuild® sealant (from Akzo Nobel Coatings) were applied to the test panels, then Autobase® (Akzo Nobel Coatings) was spray applied. The thus prepared non-pigmented coating was applied to the spray panels thus prepared. Both non-pigmented coatings excel in excellent fluidity and appearance.

Claims (30)

1. A coating composition comprising a polyisocyanate compound, a hydroxyl-functional film-forming polymer, which is an acrylic polyol, and a branched non-volatile monohydric alcohol. 2. The coating composition of claim 1, further comprising a diluent. 3. The coating composition of claim 1, wherein the monohydroxy alcohol has at least 12 carbon atoms on average. 4. The coating composition of claim 1, wherein the monohydroxy alcohol has at least 16 carbon atoms on average. 5. The coating composition of claim 1, wherein the monohydroxy alcohol is Gerbeh alcohol. 6. The coating composition according to claim 1, where the mass ratio of the amount of monohydric alcohol to the amount of solid acrylic polyol is in the range from 1:99 to 50:50. 7. The coating composition according to claim 1, where the mass ratio is in the range from 5:95 to 25:75. 8. The coating composition according to claim 1, where the hydroxyl-functional film-forming polymer has a Tg in excess of 25 ° C. 9. The coating composition according to claim 1, where the Tg exceeds 40 ° C. 10. The coating composition according to claim 1, where the branched non-volatile monohydroxy alcohol is aliphatic. 11. The coating composition according to claim 1, where the hydroxyl-functional film-forming polymer is obtained in the presence of a branched non-volatile monohydric alcohol. 12. A multicomponent coating composition comprising a polyisocyanate component and a hydroxyl-functional component, wherein the hydroxyl-functional component, in addition to the hydroxyl-functional film-forming polymer, which is an acrylic polyol, also contains a branched non-volatile monohydric alcohol. 13. The multicomponent coating composition of claim 12, further comprising a third component, wherein the third component is a diluent. 14. The multicomponent coating composition of claim 12, wherein the monohydroxy alcohol has at least 12 carbon atoms on average. 15. The multicomponent coating composition of claim 12, wherein the monohydroxy alcohol has at least 16 carbon atoms on average. 16. The multicomponent coating composition of claim 12, wherein the monohydric alcohol is Gerbe alcohol. 17. The multicomponent coating composition of claim 12, wherein the weight ratio of the amount of monohydric alcohol to the amount of solid acrylic polyol is in the range from 1:99 to 50:50. 18. A multi-component coating composition according to claim 17, wherein the weight ratio is in the range from 5:95 to 25:75. 19. The multicomponent coating composition of claim 12, wherein the hydroxyl-functional film-forming polymer has a Tg in excess of 25 ° C. 20. The multicomponent composition for coating according to claim 19, where the Tg exceeds 40 ° C. 21. The multicomponent coating composition of claim 12, wherein the branched, nonvolatile monohydric alcohol is aliphatic. 22. The multicomponent coating composition of claim 12, wherein the hydroxyl-functional film-forming polymer is prepared in the presence of a branched non-volatile monohydric alcohol. 23. The method of refinishing a vehicle, comprising applying to a vehicle a composition for coating according to claim 1. 24. A method of refinishing a vehicle, comprising applying to a vehicle a multi-component coating composition of claim 12. 25. A non-pigmented coating composition comprising a coating composition according to claim 1. 26. A non-pigmented coating composition comprising a coating composition according to claim 12. 27. A method for producing a multilayer coating, comprising (a) applying a primer composition to a substrate, (b) applying a non-pigmented coating composition according to claim 1 over a primer coating and curing the multilayer coating. 28. A method for producing a multilayer coating, comprising (a) applying an primer composition to an optionally coated substrate, (b) optionally curing the primer coating, (c) applying the unpigmented coating composition of claim 12 over the primer coating and curing the multilayer coating. 29. The method according to item 27, where the substrate is coated before applying a primer coating at stage (a). 30. The method of claim 28, further comprising the step of curing the primer coating applied in step (a) before applying the unpigmented coating in step (c).