JP3232390B2 - Paint composition for aerosol - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating composition for aerosols, and more particularly, to a coating composition for aerosols which can be used for repairing coating films in a wide range of fields such as home use and industrial use. About.

[0002]

2. Description of the Related Art Conventionally, as an aerosol paint for repairing a defective portion of a painted film, a cold-drying paint has been used as an aerosol. In the automotive repair field, lacquer paints are usually aerosolized, but paints comprising a combination of an acrylic polyol and a polyfunctional isocyanate curing agent are preferred from the viewpoint of coating properties such as finishability and weather resistance. desirable. However, the paint is a two-pack type and cannot be practically used as an aerosol paint. If a one-part paint having a curing agent component can be aerosolized, it is possible to easily form a coating film having excellent performance such as excellent finishability and weather resistance on all parts of the vehicle body. . The aerosolization of such paints has been desired.

[0003]

Means for Solving the Problems The inventors of the present invention have made intensive studies to solve the above-mentioned problems, and as a result, have found that aerosolization is carried out using a curable resin composition comprising siloxy groups and isocyanate groups. Was found to be extremely effective, and the present invention was completed.

That is, the present invention provides (a) a resin containing at least one functional group selected from a siloxy group and an isocyanate group, and (b) a resin selected from a siloxy group and an isocyanate group and containing the resin (a). the functional group capable of reacting with functional groups, compounds containing at least one or more, and a (c) siloxy group dissociating catalyst (d) above
(A) and component (b) is either or both of the components of
In addition, the present invention relates to a coating composition comprising an alkoxysilyl group-containing resin composition and an organic solvent, and a coating composition for aerosol comprising a propellant.

Hereinafter, the present invention will be described in detail.

In the present invention, the siloxy group has the following formula (I)

[0007]

Embedded image

Wherein R ₁ , R ₂ and R ₃ may be the same or different and each represents an alkyl group having 1 to 18 carbon atoms, a phenyl group or an allyl group.

In the present invention, the resin (a) containing at least one functional group selected from the siloxy group and the isocyanate group is usually a vinyl monomer having each of these reactive functional groups. Is appropriately selected, and is copolymerized with other vinyl monomers copolymerizable therewith by a conventional method such as a solution polymerization method in the presence of a radical polymerization initiator. Specifically, a monomer mixture containing one or both of a siloxy group-containing vinyl monomer and an isocyanate group-containing vinyl monomer is copolymerized.

Typical examples of the siloxy group-containing vinyl monomer include, for example, trimethylsiloxyethyl (meth) acrylate, trimethylsiloxypropyl (meth) acrylate, trimethylsiloxybutyl (meth) acrylate, and triethylsiloxyethyl (meth). )
Examples include trialkylsiloxyalkyl (meth) acrylates such as acrylate, triethylsiloxypropyl (meth) acrylate, and triethylsiloxybutyl (meth) acrylate. However, the present invention is not limited to this. Any compound can be used as long as it is converted into a siloxy group with the silylating agent. That is, hydroxyethyl (meth) acrylate with ε-caprolactone added thereto, compounds obtained by converting polyoxyalkylene glycol (meth) acrylates into siloxy groups with silylating agents such as trimethylchlorosilane and t-butyldimethylchlorosilane, etc. Can also be used.

Representative examples of the isocyanate group-containing vinyl monomer include, for example, isocyanate ethyl (meth) acrylate, isocyanate propyl (meth) acrylate, and meta-isopropenyl-α, α-dimethylbenzyl isocyanate. Examples thereof include, but are not limited to, adducts of a hydroxyl group-containing vinyl monomer such as hydroxyethyl (meth) acrylate and a polyfunctional isocyanate compound such as isophorone diisocyanate.

Representative examples of other vinyl monomers copolymerizable with the above-mentioned vinyl monomer having a reactive functional group include vinyl aromatic compounds such as styrene, α-methylstyrene and vinyltoluene. Group compound: methyl (meth)
Acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, (n-, i-, t-) butyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) Acrylate or n-octyl (meth) acrylate, decyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, cyclohexyl (meth) acrylate or the like, an alkyl ester having 1 to 24 carbon atoms of acrylic acid or methacrylic acid or Cycloalkyl ester; alkoxyalkyl ester having 2 to 18 carbon atoms of acrylic acid or methacrylic acid such as methoxybutyl (meth) acrylate, methoxyethyl (meth) acrylate, ethoxybutyl (meth) acrylate; Oro-butyl (meth) acrylate, perfluoro-iso-nonyl (meth) acrylate, perfluoroalkyl (meth) acrylates such as perfluorooctyl ethyl (meth) _{acrylate; CF 2 = CF 2, CHF} = CF 2, CH 2 = C
During F _2, CClF = CF _2, etc. formula CX ₂ = CX ₂ (formula, X is shown H, Cl, Br, F, an alkyl group or a haloalkyl group same or different. However, at least one in formula And a fluoroolefin represented by the formula (I): Further, one of these monomers and / or
Or a polymer of a higher monomer having a copolymerizable double bond at one end, a so-called macromonomer is also exemplified as a monomer copolymerizable with a vinyl monomer having a reactive functional group. . These can be appropriately selected and used according to desired physical properties.

Solvents used in the solution polymerization of the above monomer mixture include, for example, alkylbenzene derivatives such as benzene, toluene and xylene; acetate solvents such as ethyl acetate, propyl acetate, amyl acetate, methoxybutyl acetate and cellosolve acetate. Ether solvents such as dioxane, ethylene glycol diethyl ether, ethylene glycol dibutyl ether and diethylene glycol diethyl ether; ketone solvents such as methyl isobutyl ketone; and these can be used alone or as a mixture of two or more.

Examples of the radical polymerization initiator include benzoyl peroxide, di-t-butyl hydroperoxide, t-butyl hydroperoxide, cumyl peroxide,
Peroxides such as cumene hydroperoxide, diisopropylbenzene hydroperoxide, t-butylperoxybenzoate, lauryl peroxide, acetyl peroxide, t-butylperoxy-2-ethylhexanoate; α, α'-azo Examples include azo compounds such as bisisobutyronitrile, α, α'-azobis-2-methylbutyronitrile, azobisdimethylvaleronitrile, and azobiscyclohexanecarbonitrile.

The resin (a) may further contain an alkoxysilyl group from the viewpoint of improving curability and acid resistance.
In order to incorporate the alkoxysilyl group, an alkoxysilyl group-containing vinyl monomer is further used as the above-mentioned copolymer component.

Representative examples of the alkoxysilyl group-containing vinyl monomer include, for example, vinyltrimethoxysilane, vinyltriethoxysilane, and γ- (meth) silane.
Acryloyloxypropyltrimethoxysilane, γ-
(Meth) acryloyloxypropyldimethoxymethylsilane, γ- (meth) acryloyloxypropyltriethoxysilane, styrylethyltrimethoxysilane,
Vinyl tris (2-methoxyethoxy) silane, vinyl triacetooxy silane and the like can be mentioned.

The resin (a) obtained by a usual radical solution polymerization method using the above-mentioned vinyl monomer, solvent and polymerization initiator has a weight average molecular weight of 1,000 to 200,000.
0, more preferably in the range of 2,000 to 100,000. When the weight average molecular weight is less than 1,000, satisfactory drying properties are hardly obtained, and the weather resistance and durability of the obtained coating film tend to decrease. On the other hand, 20
If it is larger than 000, the finished appearance is deteriorated, which is not preferable.

In the present invention, the compound (b) containing at least one functional group selected from a siloxy group and an isocyanate group and capable of reacting with the functional group contained in the resin (a) may be a low molecular compound. It may be a resin, and when the resin (a) has a siloxy group, it is a compound containing an isocyanate group or a resin containing an isocyanate group and a siloxy group, and when the resin (a) has an isocyanate group. Are siloxy group-containing compounds or resins containing siloxy and isocyanate groups. The compound (b)
May be the same as the resin (a) when the resin (a) has both a siloxy group and an isocyanate group.

As the isocyanate group-containing compound used as the component (b), a polyisocyanate compound containing at least two isocyanate groups in one molecule can be used. Representative examples include tetramethylene diisocyanate. Aliphatic diisocyanates such as hexamethylene diisocyanate and trimethylhexamethylene diisocyanate; cycloaliphatic diisocyanates such as hydrogenated xylylene diisocyanate, 1,4-diisocyanate cyclohexane or isophorone diisocyanate; tolylene diisocyanate, 4,4 ′
Organic diisocyanates themselves such as aromatic diisocyanates such as diphenylmethane diisocyanate, or each of these organic diisocyanates and polyhydric alcohols,
Adducts with low molecular weight polyesters or water, or cyclized polymers of each of the above organic diisocyanates,
Furthermore, an isocyanate biuret body and the like can be mentioned. Examples of typical commercially available products include "Varnock D-750, -800, DN-950, -955,-
970, -922 or 15-455 "[products of Dainippon Ink and Chemicals, Inc.]," Desmodur L,
N, HL, IL, or N3390 ”[manufactured by Bayer AG in West Germany],“ Sumijur N-3200 or N-3500 ”[manufactured by Sumitomo Bayer Urethane Co., Ltd.],“ Takenate D-102, -202, -110N ”
Or -123N] [product of Takeda Pharmaceutical Co., Ltd.],
“Coronate L, HL, EH or 203” [product of Nippon Polyurethane Industry Co., Ltd.] or “Duranate 24
A-90CX, TPA-90EK "[Asahi Kasei Corporation
Product]. Further, as the component (b), a resin obtained by copolymerizing a vinyl monomer containing an isocyanate group with styrene, (meth) acrylates, or the like can be used.

As the polyisocyanate compound, in particular, an adduct of a diisocyanate and a long-chain polyhydric alcohol,
For example, the above-mentioned diisocyanate, alkylenediol having 10 to 30 carbon atoms, polycaprolactone polyol,
It is preferable to use a polyisocyanate compound obtained by reacting with a polyol such as a polyether polyol or a polyester polyol because excellent scratch resistance can be imparted. Among them, a polyisocyanate compound obtained by reacting a diisocyanate compound with polycaprolactonediol and / or triol is preferable in terms of scratch resistance and solubility in a solvent. Specific examples of such polyisocyanate compounds include, for example, “Duranate E-402-90T, E-405-80T”
Commercial products such as [Asahi Kasei Kogyo Co., Ltd. products] can be used.

As the siloxy group-containing compound used as the component (b), a compound having at least two siloxy groups in one molecule can be used, and specifically, a compound having at least two hydroxyl groups in one molecule. Any compound can be used as long as it is a compound in which the hydroxyl group of the compound has been converted to a siloxy group with a known and commonly used silylating agent. Representative of those compounds include, for example, ethylene glycol, propylene glycol, 1,2-butanediol,
Dihydric alcohols such as 1,3-butanediol and 2,3-butanediol; polylactone diols obtained by adding lactones such as ε-caprolactone to these dihydric alcohols; glycerin, trimethylolpropane, and pentaerythritol Polylactone polyols obtained by adding lactones such as ε-caprolactone to these trihydric or higher alcohols with a silyl group such as trimethylchlorosilane or t-butyldimethylchlorosilane. And the like. Further, as the component (b), the siloxy group-containing vinyl monomers listed in the description of the resin (a) are copolymerized with other vinyl monomers such as styrene and (meth) acrylates. The resulting resin can also be used.

The siloxy group- and isocyanate group-containing resin used as the component (b) include the siloxy group-containing vinyl monomer and the isocyanate group-containing vinyl monomer listed in the description of the resin (a). Those obtained by copolymerizing the monomer and other vinyl monomers copolymerizable therewith by a conventional method can be used.

The component (b) may further contain an alkoxysilyl group from the viewpoint of improving curability and acid resistance.
In order to contain the alkoxysilyl group, a vinyl monomer containing an alkoxysilyl group listed in the description of the resin (a) is further used as the above-mentioned copolymer component.

In the present invention, the above resin composition is preferably a composition comprising a resin containing two or more siloxy groups in one molecule as the component (a) and a polyisocyanate compound as the component (b). Or a resin containing a siloxy group and an alkoxysilyl group as the component (a),
It is suitable from a practical point of view that the composition is selected from a polyisocyanate compound as a component.

As the resin component of the present invention, only the above (a) and (b) are sufficient, but if necessary,
One compound (d) which is different from the above (a) and (b) and contains two or more functional groups of one or more selected from a siloxy group, an isocyanate group and an alkoxysilyl group in one molecule As described above, it may be added to the resins (a) and (b).

The compound (d) may be a low-molecular compound or a resin. As the low-molecular compound, those listed for the compound (b) can be used. As the resin, the structural unit of the resin (a) can be used. The above-mentioned conventional methods are appropriately selected from siloxy group-containing vinyl monomers, isocyanate group-containing vinyl monomers, alkoxysilyl group-containing vinyl monomers and other vinyl monomers. Can be used.

The mixing ratio of the above (a) and (b) (and if necessary, the component (d) is also included) is appropriately selected depending on the content of the reactive functional group contained in the resin composition. can do.

The siloxy group content in the resin composition is a composition amount as a siloxy group-containing vinyl monomer and a compound in the resin composition, and is 5 to 60% by weight in solid content, and more preferably 1 to 60% by weight.
Preferably it is in the range of 0 to 50% by weight. If it is less than 10% by weight, the crosslink density of the coating film tends to be low, and the physical properties of the coating film tend to deteriorate. On the other hand, even if it exceeds 50% by weight, no further improvement in performance can be expected.

The siloxy groups in the resin composition are hydrolyzed by moisture in the air after coating to form hydroxyl groups.
Therefore, the composition amount of the isocyanate group-containing vinyl monomer and the compound in the resin composition is such that the hydroxyl group formed from the isocyanate group and the siloxy group is equivalent to NCO / O in equivalent ratio.
It is preferable that H = 0.5 to 2.0.

The content of the alkoxysilyl group in the resin composition is 0 to 40% by weight, and more preferably 3 to 30% by weight as a solid content of the vinyl monomer having an alkoxysilyl group in the resin composition. % Is preferable. 4
If it exceeds 0% by weight, the cured coating film tends to be brittle.

The siloxy groups in the composition of the present invention are hydrolyzed by moisture in the air after coating to form hydroxyl groups. In order to promote this hydrolysis reaction, the siloxy group dissociation catalyst (c) is an essential component in the present invention. Representative examples of the compound used as the siloxy group dissociation catalyst (c) include, for example, phosphoric acid and its acidic ester and phosphite; sulfonic acid such as paratoluenesulfonic acid and naphthalenedisulfonic acid and its amine salt; Examples thereof include carboxylic acids such as trichloroacetic acid and trifluoroacetic acid and acidic compounds such as amine salts thereof.

The addition amount of the siloxy group dissociation catalyst (c) is preferably in the range of 0.01 to 10% by weight, more preferably 0.1 to 5% by weight, based on the solid content of the resin composition. . If the amount is less than 0.01% by weight, the curability decreases,
If it exceeds 10% by weight, the water resistance of the coating film tends to be poor.

The composition of the present invention comprises the above-mentioned resin component and a siloxy group dissociation catalyst. In order to further promote the reaction between the generated hydroxyl group and the isocyanate group, a commonly used urethane such as an organic tin compound such as dibutyltin dilaurate is used. The catalyst may be added in advance.

In order to prevent hydrolysis of siloxy groups and secure long-term storage stability, it is desirable to add a water binding agent for capturing moisture to the composition of the present invention. As a water binder, trimethyl orthoformate, triethyl orthoformate,
Trialkyl orthoformates such as tributyl orthoformate;
Trialkyl orthoacetates such as trimethyl orthoacetate, triethyl orthoacetate and tributyl orthoacetate; and monoisocyanate compounds such as phenyl isocyanate, p-chlorophenyl isocyanate and p-toluenesulfonyl isocyanate, for example "Additive TI"
Commercial products such as (manufactured by Sumitomo Bayer Urethane) can be used.

The resin composition obtained as described above can be used as a one-pack type paint by adjusting the viscosity to an appropriate value with a diluting solvent.

The diluting solvent used has a flash point of 0
It is not particularly limited as long as it is an organic solvent having a temperature of not less than ℃, for example, toluene, xylene, hydrocarbons such as mineral spirits,
Ketones such as methyl isobutyl ketone, esters such as ethyl acetate, butyl acetate and amyl acetate, ethers such as dioxane, ethylene glycol, diethylene glycol
Methyl ether, ethyl ether, propyl ether such as propylene glycol, hexylene glycol and the like;
Glycoyl ether acetate such as butyl ether, and propionates are exemplified. These can be used alone or in combination of two or more, and it is desirable from the viewpoint of safety to select the organic solvent in the composition so that the flash point of the whole organic solvent is preferably 21 ° C. or higher.

The composition of the present invention comprises the above-mentioned paint component and a propellant, and the paint component can be filled into an aerosol container together with the propellant to obtain an aerosol paint. As the propellant, known dimethyl ether, LP gas and the like can be used alone or in combination.

The paint component of the composition of the present invention may be further blended with a cellulose resin such as nitrocellulose or cellulose acetate butyrate, or an epoxy resin to improve physical properties. Good. In addition, if necessary,
Pigments (eg, aluminum paste, pearl powder, graphite, metallic pigments such as MIO, titanium oxide,
Organic and inorganic coloring pigments such as carbon black, extenders, etc.), ultraviolet absorbers, antioxidants, surface conditioners, dispersants and other paint additives.

When filling the composition of the present invention into an aerosol container, it is desirable to work so as not to mix moisture.

[0040]

The present invention will be described below in detail with reference to examples.

Production of Reactive Functional Group-Containing Resin Production Example 1 A reactor was equipped with a thermometer, a thermostat, a stirrer, a reflux condenser, a dropping pump, and charged with 60 parts by weight of xylene. 103.5 parts by weight of a mixture of a monomer and a polymerization initiator shown in Table 1 was added to 110
The solution was dropped at a constant rate over 3 hours using a dropping pump while keeping the temperature at ° C. After completion of the dropwise addition, the temperature was maintained at 110 ° C. for 1 hour, and the stirring was continued. Thereafter, a solution prepared by dissolving 0.5 part by weight of an additional polymerization initiator in 5 parts by weight of xylene was added dropwise at a constant rate over 1 hour, and the reaction was terminated at 110 ° C. for 1 hour. The obtained siloxy group-containing resin solution has a nonvolatile content of 60.
It was a homogeneous and transparent solution with a weight% of Gardner viscosity LM. The weight average molecular weight of this resin was 14,000.

Production Examples 2 to 5 The same procedures as in Production Example 1 were carried out except that the mixture of the monomer and the polymerization initiator and the additional polymerization initiator were used as shown in Table 1, and the reactivity was changed. A functional group-containing resin solution was obtained. Table 2 shows the property values of the obtained resin and resin solution.

[0043]

[Table 1]

[0044]

[Table 2]

Examples and Comparative Examples The reactive functional group-containing resin solution, catalyst, water binder, polyisocyanate compounds (* 1) to (* 3) obtained in the production examples, and an organic solvent (xylene / ethyl acetate = 80 /
20) was mixed and stirred with the composition shown in Table 3, and the viscosity was adjusted to about 15 seconds (Ford cup # 4/25 ° C) to prepare a clear coating component.

(Note 1) Sumidur N-3500: manufactured by Sumitomo Bayer Urethane Co., Ltd., nonvolatile content 100%, N
An isocyanurate type of hexamethylene diisocyanate having a CO content of 21.6%.

(Note 2) Duranate E-402-90T
...... Asahi Kasei Kogyo Co., Ltd., 90% non-volatile content, 8.5% NCO content, polycaprolactone polyol modified polyisocyanate.

(Note 3) Duranate E-405-80T
... Asahi Kasei Kogyo Co., Ltd., nonvolatile content 80%, NCO content 7.1%, polycaprolactone polyol modified polyisocyanate.

Next, these clear paint components and dimethyl ether were filled into an aerosol container at a volume ratio of 1: 1 to obtain an aerosol paint composition.

Each of the obtained aerosol paints was placed at room temperature (20
C), and sprayed onto a tin plate, or onto a coated plate obtained by applying a clear paint for a new car to the tin plate and baking and drying it.
Table 4 shows the performance test results of the obtained test coated plates.

[0051]

[Table 3]

[0052]

[Table 4]

The test method is as follows.

(1) Suitability of spray: Aerosol was applied to a tin plate for a certain period of time, and the state of fog was visually observed. The state of the uniform fog was indicated by ○, and the state of the coarse fog in which coarse particles were observed was indicated by ×.

(2) Anti-dripping property: The test-coated plate coated with azole was vertically stood, and the degree of dripping was visually evaluated. A sample without sagging was rated as "O", and a sample with sagging was rated as "x". (3) Finishing property: The smoothness of the coating film was visually evaluated.

：: good △: slightly bad ×: poor (4) Acid resistance After applying the clear paint for a new car, spraying each aerosol paint on a baked and dried paint plate, and then drying at room temperature for 7 days, 40% sulfuric acid was spotted, and the state of the coated surface after heating at 85 ° C. for 30 minutes was evaluated.

：: There is almost no change in the coated surface. ：: Etching has occurred. X: Remarkable etching has occurred. (5) Accelerated weather resistance A coated plate prepared in the same manner as in (4) was used for a sunshine weatherometer. For 1,000 hours, the presence or absence of a change in the coated surface was confirmed.

：: Little change in the coated surface X: Water marks were observed on the coated surface and the gloss was greatly reduced (6) Storage stability For each aerosol paint, the viscosity change after storage at 40 ° C. for one month, The change in the coating liquid state was examined.

：: Little change in viscosity, etc. ×: Thickening or gelling occurred (7) Scratch resistance Dalmac cleanser (Yamasan Shoten) and water were mixed in a ratio of 3: 2 to prepare an abrasive. The tester used was a dye fastness friction tester FR-II (manufactured by Suga Test Instruments Co., Ltd.). The above-mentioned abrasive was attached to the flannel, and a load of 500 g was applied thereto, and the coated surface of the coated plate prepared in the same manner as in (4) was rubbed back and forth 20 times.
Thereafter, the coated surface was washed with running water and air-dried, and then the 20-degree specular reflectance (20 ° G value) of the coated surface was measured. The 20 ° G gloss retention was calculated according to the following equation, and the scratch resistance was evaluated from the value.

[0060]

(Equation 1)

：: 20 ° G Gloss retention 30% or more Δ: 〃 10% or more and less than 30% ×: 未 満 less than 10%

[0062]

According to the present invention, an azo compound is prepared by using a curable resin composition comprising a siloxy group and an isocyanate.
Aerosol coating composition having excellent sprayability and anti-sagging properties, as well as excellent coating properties such as finishability and weather resistance that could not be obtained with conventional lacquer type aerosol coatings. And by introducing an alkoxysilyl group into the curing system, it is possible to obtain an aerosol coating composition having excellent acid resistance and curability. Also, by using a specific polyisocyanate compound in the resin composition, an aerosol coating composition having excellent scratch resistance can be obtained. The composition of the present invention is for household use,
It can be used for repairing coatings in a wide range of fields such as industrial use.

────────────────────────────────────────────────── ─── Continuation of front page (56) References JP-A-3-250016 (JP, A) JP-A-4-80268 (JP, A) JP-A-3-172318 (JP, A) (58) Field (Int. Cl. ⁷ , DB name) C09D 175/04

Claims (3)

(57) [Claims] An aerosol coating composition comprising a coating component comprising the following resin composition and an organic solvent, and a propellant. "(A) a resin containing at least one or more functional groups selected from a siloxy group and an isocyanate group, and (b) a functional group selected from a siloxy group and an isocyanate group and reacting with a functional group contained in the resin (a). compounds containing at least one or more, (c) a siloxy group dissociating catalyst consists city, contains (d) is above the (a) component and (b) either or both further alkoxysilyl groups of component, Resin composition. " Wherein (a) 2 component siloxy groups in one molecule
The coating composition for aerosol according to claim 1, wherein the resin composition contains at least one resin , and the component (b) is a polyisocyanate compound. 3. The aerosol coating composition according to claim 2 , wherein the component (b) is a polyisocyanate compound obtained by reacting a diisocyanate compound with polycaprolactone diol and / or triol. "