JPS63191869A - Topcoating method - Google Patents

Abstract

PURPOSE:To improve the durability, water repellency, etc. of a coating film and to prevent the lowering of gloss, cracking, discoloration, fading, etc., by applying a solid color and then a top clear paint composed of a specified curable paint to the coated surface to finish it. CONSTITUTION:A dispersion stabilizer composed of an org. solvent-soluble fluoropolymer having a weight-average MW of 5,000-120,000 and a fluorine content of 1-60wt.% and comprising a fluoroolefin as an essential ingredient is prepd. A radical-polymerizable monomer (e.g., methyl acrylate) is polymerized in the presence of said dispersion stabilizer in an org. solvent in which said monomer is soluble but the resulting polymer is insoluble (e.g., toluene). A transparent top clear paint is prepd. from the resulting curable paint mainly composed of a non-aqueous dispersion. A solid color is applied to an automobile, etc., and the resulting transparent top clear paint is then applied to the coated surface to finish it.

Description

[Detailed Description of the Invention] Ll rise flJl! The present invention uses a so-called two-coat one-bake method in which a solid coat containing pigment is applied, then a transparent top clear paint is applied, and the coating is cured by heating. , heat hardening,
Next, a transparent top clear paint is coated over and over again, and then heated and cured.The purpose of this method is to apply a two-coat, two-bake method to achieve a solid color finish. The objective is to improve so-called weather resistance such as reduction in gloss, cracking, discoloration, fading, and blistering.

There are solid color finishes and metallic color finishes for top-coat finishes on ZEN cars, but in the case of metallic color finishes, after applying the metallic coat, apply a wet-on-wet clear coat and bake with a 2-coat bake. However, in the case of solid color finishing, the amino alkyd resin paint used for solid colors has gloss and excellent texture, so it is necessary to improve gloss. The need for clear coating on solid coats has become relatively small.However, in recent years, there has been an increasing demand for a variety of coating colors, further improvements in finish, and improved weather resistance. Clear coating began to be used.In other words, clear coating made it possible to use pigments that had poor acid and alkali resistance and could not be used in conventional one-coat solids, expanding the range of pigment selection. This makes it possible to cover a wider variety of color gamuts.

Additionally, by adding a UV absorber to the clear coat, it is possible to improve the weather resistance of the clear coat itself, but it also prevents the solid coat and pigments from deteriorating due to UV rays. Pigments that can be used have emerged from among pigments, and the color gamut that can be covered has further expanded.

In addition, by applying one layer of clear coat, it has become possible to obtain a finished appearance with excellent durability (double-layer feel).

Furthermore, by using an organic solvent-soluble fluorine-containing polymer in the clear coat, it has become possible to further improve the weather resistance of the two-coat solid coat.

In other words, fluorine-containing polymers generally have significantly lower intermolecular cohesive force than other organic polymers, are chemically stable, and when formed into a coating film, have water repellency, oil repellency, stain resistance, It exhibits non-stick properties and, more importantly, has excellent weather resistance. Among fluorine-containing polymers having such excellent practical properties, fluorine-containing polymers that are soluble in organic solvents at room temperature have the properties of the fluorine-containing polymers described above, and further, It has the characteristics of excellent workability and painting workability.

However, in order to make the fluorine-containing polymer soluble in an organic solvent at room temperature, the thermal and mechanical properties that should originally be provided as a coating film may deteriorate. Furthermore, fluorine-containing polymers are significantly more expensive than organic polymers such as acrylic resins and alkyd resins that are generally used in clear coats, and their effectiveness can be achieved with the minimum necessary fluorine atom content. It is essential that

4. The present invention has been made for the purpose of solving the above-mentioned drawbacks of the two-coat solid coat method.

That is, the present invention provides a solid color finishing method in which a pigment-containing solid coat is applied, and then a transparent top clear paint is applied to the painted surface.

The above-mentioned top clear paint contains fluoroolefin as an essential component, and has a weight average molecular weight of about 5.000 to about 1.
20,000 and a fluorine atom content of about 1 to about 60% by weight
In an organic liquid in which the radically polymerizable monomer is soluble and the polymer formed by the radically polymerizable monomer is insoluble in the presence of a dispersant consisting of an organic solvent-soluble fluorine-containing polymer. , relates to a solid coat finishing method characterized by using a curable paint whose main component is a non-aqueous dispersion (hereinafter abbreviated as rF-NADJ) obtained by polymerizing the radically polymerizable monomer.

A feature of the present invention is that a non-aqueous dispersion (F-NAD) containing a fluorine-containing polymer containing the above-mentioned fluoroolefin as an essential component is used as a top clear coating in a two-coat system.
), and as a result, the above object can be achieved.

According to the method of the present invention, it is possible to form a topcoat film that simultaneously has the performance that a paint film should have and the properties based on fluorine atoms. In other words, it is chemically stable, has excellent weather resistance, water repellency, oil repellency, stain resistance, is non-adhesive, and has a low refractive index, which are characteristics unique to fluorocarbon resins. It has excellent thermal, chemical, and mechanical properties such as alkalinity, adhesion to the base coat, hardness, gloss, sharpness, and impact resistance.
It only needs to be present in the continuous phase (dispersion stabilizer) and does not need to be present inside the polymer particles of the dispersion. Even if the amount of the fluorine-containing monomer used is reduced, the same characteristics based on fluorine atoms can be exhibited.

In other words, it also has the advantage that a coating film that is significantly advantageous in terms of price can be obtained.

Therefore, by using the top clear paint of the present invention in a two-coat system, it is possible to prevent the top coat from deteriorating in gloss, cracking, peeling, blistering, etc. after long-term exposure, and it is possible to significantly improve weather resistance. Furthermore, since the water repellency of the top coat surface can be maintained for a long period of time, it is possible to prevent water from penetrating into the paint film, and it also prevents water from penetrating into the paint film, as well as between the top coat film and the coat film, and between the coat film and intermediate coat film.・It can also prevent the formation of water accumulation (blister) between the layers of the undercoat film. Furthermore, by blending the above F-NAD into the top clear paint, it is possible to significantly improve the finished appearance such as the gloss and sharpness of the two-coat coating, and to maintain this for a long period of time.
Furthermore, the occurrence of peeling, blistering, etc. between the top coat film and the base coat film can be almost completely prevented.

The method of the present invention will be explained in more detail below.

Solid coat> The solid coat paint used in the present invention is widely used in the past, and consists of a curable resin composition, a base containing a colored pigment as a main component, and a coating film that is colored in a uniform manner. It is something that forms. Specifically, the curable resin composition includes a base resin such as an acrylic resin, a polyester resin, an alkyd resin, an epoxy resin, a fluorine-containing resin, or a urethane resin, and a crosslinking agent (an amino resin, a blocked polyisocyanate compound, etc.). A thermosetting resin composition consisting of a thermosetting resin composition or a thermosetting resin composition prepared by adding a curing agent such as a polyisocyanate compound to the base resin at room temperature or at a low temperature (approximately 140°C
Below) resin compositions that are crosslinked by heating, etc. can be mentioned.

These resin compositions may further be blended with a resin that does not undergo crosslinking and curing reactions, such as cellulose acetate butyrate resin.The coloring pigment used in the paint may be any commonly used pigment. good, i.e.
From blue, red, green, yellow organic or inorganic pigments with relatively low hiding power (e.g. phthalocyanine blue, azo red pigments) to white, black, red inorganic pigments with high hiding power (e.g. titanium oxide, carbon blur). These include coloring pigments such as red oxide and red red pigment. These pigments may be used alone.

Two or more types may be used in combination. An appropriate amount is selected depending on the type of pigment.

Top clear paint> This is a paint that can be applied to a solid coat surface to form a transparent paint film, and is a curable paint containing F-NAD as the main component.

Specifically, the fluorine-containing polymer used as a dispersion stabilizer for F-NAD contains a fluoroolefin as an essential component,
Alkyl vinyl ether, alicyclic
yclic) Weight average molecular weight s in which one or more unsaturated monomers selected from vinyl ether, hydroxy vinyl ether, olefin, haloolefin, unsaturated carboxylic acid and its ester, and carboxylic acid vinyl ester are copolymerized components. ,ooo~120,000(
It is a polymer that is soluble in organic solvents at room temperature and has a number average molecular weight of about 1,000 to 60,000) and a fluorine atom content of 1 to 60% by weight. As the fluoroolefin as a copolymerization component in the fluorine-containing polymer, tetrafluoroethylene, chlorotrifluoroethylene, vinyl fluoride, vinylidene fluoride, etc. are used.

In addition, examples of alkyl vinyl ethers that are other copolymerization components include ethyl vinyl ether, inbutyl vinyl ether, n-butyl vinyl ether, etc.; examples of alicyclic vinyl ethers include cyclohexyl vinyl ether and its derivatives; examples of hydroxy vinyl ethers include hydroxy Niolefins and hyhaloolefins such as butyl vinyl ether include ethylene, propylene, imbutylene, vinyl chloride, vinylidene chloride, etc.; carboxylic acid vinyl esters include vinyl acetate, vinyl n-butyrate, etc.; and unsaturated carboxylic acids and their esters. Examples include unsaturated carboxylic acids such as acrylic acid, methacrylic acid, and crotonic acid; and methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, butyl acrylate, hexyl acrylate, octyl acrylate, and lauryl acrylate. 01-1 of acrylic acid or methacrylic acid such as methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, butyl methacrylate, hexyl methacrylate, octyl methacrylate, and lauryl methacrylate. Alkyl ester; 02-6 hydroxyalkyl ester of acrylic acid or methacrylic acid such as hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate; N,N-dimethylaminoethyl (meth)acrylate.

Examples include unsaturated carbon esters such as N,N-diethylaminoethyl (meth)acrylate.

Each of these radically polymerizable monomers can be used alone or in combination of two or more, and if necessary, a part of the monomer can be used with other radically polymerizable monomers. , for example, vinyl aromatic compounds such as styrene, α-methylstyrene, vinyltoluene, (meth)acrylonitrile, etc. may be substituted.

In addition to the monomers exemplified above, derivatives of the above monomers such as carboxylic acid group-containing fluoroolefins, glycidyl group-containing beer ethers, etc. can also be used.

Note that if the fluorine atom content in the fluorine-containing polymer is less than 1%, the characteristics of the fluorine-containing polymer will not be fully exhibited, and the
%, the solubility in organic solvents decreases.

Furthermore, a polymerizable double bond may be introduced into the fluorine-containing polymer to achieve grafting with the core portion of the dispersed particles. A monomer containing a carboxylic acid group is used as a copolymerization component of the polymer, and an unsaturated monomer containing a glycidyl group (
For example, this reaction can be carried out by reacting a glycidyl group-containing acrylic copolymer with a carboxyl group-containing unsaturated monomer. can also be done.

Other possible combinations include acid anhydride groups and hydroxyl groups, acid anhydride groups and mercapto groups, incyanate groups and hydroxyl groups, and the like. The general conditions under which addition reactions occur between such combinations of reactive groups are well known, and the temperatures at which these reactions occur depend on the particular combination of reactive groups chosen and can be controlled by the use of catalysts. Needless to say, the scales have changed.

By the above reaction, the dispersion stabilizer resin can have at least 0.1 polymerizable double bonds in the molecule on average.

Of course, in the present invention, it is not necessary for the dispersion stabilizer resin to have a polymerizable double bond, but by introducing a polymerizable double bond, a covalent bond is formed between the polymer forming the particles and the dispersion stabilizer, Further improvements in storage stability and mechanical stability of the dispersion can be achieved.

As a specific example of the above-mentioned fluorine-containing polymer, for example, hydroxyl group-containing organic solvent-soluble "Lumiflon" series (for example, "Lumiflon LF200J weight average molecular weight of about 50,000
0, manufactured by Asahi Glass Co., Ltd.), and organic solvent-soluble fluorine-containing polymers are also available from Daikin Industries, Ltd., Central Glass Co., Ltd., Pennwald Co., Ltd., and others.

The molecular weight of the fluorine-containing polymer used as a dispersion stabilizer is within the range of weight average molecular weight of 5,000 to 120,000 (number average molecular weight of about 1,000 to 60,000), but one molecular weight is about 5. When the molecular weight is less than 000, the stabilization of the dispersed particles is insufficient and aggregation and sedimentation tend to occur.
When it exceeds 0,000, the solubility of the fluorine-containing polymer in organic solvents decreases and the viscosity of the dispersion liquid significantly increases. The production of the fluorine-containing polymer is usually carried out using a radical polymerization initiator. Examples of usable radical polymerization initiators include azo initiators such as 2.2''-azobisisobutyronitrile, 2,2'-azobis(2,4-dimethylvaleronitrile), benzoyl peroxide, and lauryl peroxide. Examples include peroxide-based initiators such as oxide and tart-butyl peroctoate, and these polymerization initiators are generally used in amounts of (12 to 10 parts by weight, preferably 0 Emulsion polymerization in an aqueous medium and solution polymerization in an organic solvent are generally adopted as the reaction format that can be used within the range of .5 to 5 weight.However, as a dispersion stabilizer, polymers dissolved in the organic solvent Use it when it is.

Various solvents can be used as organic solvents, including aromatic hydrocarbons, alcohols, esters, ketones,
In addition to glycol ethers, various commercially available thinners can also be used. These may be used alone or in combination of two or more in various proportions. The reaction temperature and reaction pressure are appropriately selected depending on the type of polymerization initiator, the type of solvent, and the reaction format.

The above-mentioned dispersion stabilizer resin used in the present invention may be used alone or in combination of two or more types having different copolymerization compositions and molecular weights.Furthermore, if necessary, other dispersion stabilizers such as , butyl etherified melamine-formaldehyde resin, alkyd resin, general acrylic resin, etc. can also be used in small amounts.

According to the present invention, at least one radically polymerizable monomer is polymerized in an organic liquid in the presence of a dispersion stabilizer resin as described above.

Although the dispersed polymer particles produced by the polymerization are not substantially dissolved in the organic liquid used in the polymerization, the fluorine-containing resin and the radically polymerizable monomer are combined with the organic solvent of the dispersion stabilizer resin solution. It is a good solvent for polymers. Organic liquids are included.

Specific examples of such organic liquids include aliphatic hydrocarbons such as hexane, heptane, and octane; benzene, toluene,
Aromatic hydrocarbons such as xylene; alcohol, ether, ester and ketone solvents such as isopropyl alcohol, n-butyl alcohol, i-butyl alcohol, octyl alcohol, cellosolve, butyl cellosolve, diethylene glycol monobutyl ether, methyl isobutyl ketone, Examples include diisobutyl ketone, ethyl acyl ketone, methylhexyl ketone, ethyl butyl ketone, ethyl acetate, isobutyl acetate, acyl acetate, 2-ethylhexyl acetate, etc. Each of these may be used alone, or two or more types may be mixed. However, in general, it is preferable to use a solvent mainly composed of aliphatic hydrocarbons, in combination with aromatic hydrocarbons or alcohol-based, ether-based, ester-based, or ketone-based solvents such as those mentioned above. Ru. Furthermore, trichlorotrifluoroethane, meta-xylene hexafluoride, tetrachlorohexafluorobutane, etc. can also be used if necessary.

The monomers polymerized in the presence of the dispersion stabilizer resin and organic liquid described above are not particularly limited as long as they are radically polymerizable unsaturated monomers, and various monomers can be used. The typical examples are as follows.

(a) Esters of acrylic acid or methacrylic acid; for example, methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, butyl acrylate,
Hexyl acrylate, octyl acrylate, lauryl acrylate, methyl methacrylate, ethyl methacrylate,
Alkyl esters of acrylic acid or methacrylic acid such as propyl methacrylate, isopropyl methacrylate, butyl methacrylate, hexyl methacrylate, octyl methacrylate, lauryl methacrylate: glycidyl acrylate, glycidyl methacrylate; allyl acrylate, allyl methacrylate, etc. 02-6 alkenyl ester of acrylic acid or methacrylic acid; 02-6 hydroxyalkyl ester of acrylic acid or methacrylic acid such as hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate; allyloxyethyl acrylate, allyloxymethacrylate 03-t alkenyloxyalkyl esters of acrylic acid or methacrylic acid, such as.

(b) Vinyl aromatic compounds: for example, styrene, α-
Methylstyrene, vinyltoluene, p-chlorostyrene vinylpyridine.

(C) α,β-ethylenically unsaturated acids: eg acrylic acid, methacrylic acid, itaconic acid.

(d) Others: 7 Acrylonitrile, methacrylonitrile, methyl impropenyl ketone; vinyl acetate, beoba monomer (shelled? product), vinyl propionate, vinyl bivalate, etc.

Particularly preferred among these monomers are monomers or monomer mixtures containing at least 40% by weight of esters of acrylic acid or methacrylic acid.

Polymerization of the above monomers is carried out using a radical polymerization initiator. Usable radical polymerization initiators include, for example, azo initiators such as 2,2-7zoisobutyronitrile and 2,2'-azobis(2,4-dimethylvaleronitrile); benzoyl peroxide, Examples include peroxide-based initiators such as lauryl peroxide and tert-butyl peroctoate, and these polymerization initiators are generally used in an amount of 0.2 to 10 parts by weight, preferably 0.2 to 10 parts by weight, per 100 parts by weight of monomers to be subjected to polymerization. can be used within the range of 0.5 to 5 parts by weight.

Further, the amount of the dispersion stabilizer resin used can vary widely depending on the type of resin, etc., but generally, the amount used is 5% based on the total amount of the monomer to be polymerized and the dispersion stabilizer.
A range of 80% by weight, preferably from about 10 to about 60% by weight is advantageous.

Furthermore, the total concentration of the radically polymerizable monomer and dispersion stabilizer in the organic solvent is generally about 30 to 70% by weight, preferably about 30 to 60% by weight.

Polymerization can be carried out by a method known per se, and the reaction temperature during polymerization can generally be in the range of about 60 to about 160°C, and the reaction usually takes about 1 to about 15 hours to complete. can be set.

F-NAD produced by the method described above has extremely excellent dispersion stability.

The top clear paint in the present invention is Okuki F-NAD
can be used as is, but it is also possible to use a combination of two or more of different copolymer compositions and molecular weights.
Furthermore, it is also possible to use small amounts of other dispersion stabilizers, such as alkyl etherified melamine-formaldehyde resins, alkyd resins, acrylic resins, etc., if necessary.

Colorants, plasticizers, curing agents, etc. may be added as necessary. Colorants include dyes, organic pigments, inorganic pigments, etc. Plasticizers include known ones, such as dimethyl phthalate and dioctyl. Examples include low molecular weight plasticizers such as phthalate, vinyl polymer plasticizers, and polymer plasticizers such as polyester plasticizers, and these can be used by mixing them into F-NAD in advance, or they can be used in the production of F-NAD. At the time, for example, it is dissolved in a radically polymerizable monomer,
It can also be distributed in the dispersed polymer particles of the resulting dispersion. Further, the curing agent cross-links and hardens the dispersion stabilizer and dispersed particles of F-NAD, such as amino resin,
Crosslinking agents such as epoxy resins and polyisocyanate resins may be used.

In the present invention, an ultraviolet absorber or a light stabilizer may be added to the solid paint and/or top clear paint. However, ultraviolet rays in sunlight can pass through such a transparent top coat film and deteriorate the solid coat film. Therefore, when solid paint and/or top clear paint contains ultraviolet absorbers and light stabilizers,
The purpose is to improve the weather resistance not only of the top coat film but also of the solid coat film, and to improve the weather resistance of the two-coat solid coat by blending the above fluorine-containing polymer into the top clear paint. 0 that can significantly compensate for
The ultraviolet absorber used in the present invention absorbs ultraviolet energy, is compatible with the resin for solid coatings and the fluorine-containing polymer for top clear coatings, or can be uniformly dispersed, and the baking temperature of the coating is low. A wide variety of conventionally known compounds can be used as long as they do not easily decompose and lose their effectiveness, and preferred examples include benzophenone, triazole, phenyl salicylate, diphenyl acrylate, and acetophenone. Further, by further using a light stabilizer in combination with these ultraviolet absorbers, the weather resistance of the base coat coating film and the top clear coating film can be further improved. The light stabilizer is one that is compatible with or can be uniformly dispersed in the resin for solid paints and the fluorine-containing polymer for top clear paints, and that does not easily decompose at temperature and lose its effectiveness during baking of paints. As long as it is, a wide range of conventionally known ones can be used, such as screws (2, 2).

6.6-tetramethyl-4-piperidyl) sebacate,
Bis(l,2,2,6.6-bentamethyl-4-piperidyl)sebacate, 2-(3,5-ditert-
butyl-4-hydroxybenzyl)-2-n-butylmalonic acid bis(1,2,2,6-bentamethyl-4-piperidyl), tetrakis(2,2,6,6-tetramethyl-4-piperidyl)-1 , 2,3,4-butanetetracarboxylate, tetrakis(1,2,2,6,6-bentamethyl-4-piperidyl)-1,2,3,4-butanetetracarboxylate, and the like.

These may be used alone or in combination of two or more.

The blending amount of the above ultraviolet absorber is 0.1 to 10% by weight based on the resin solid content of the solid paint or top clear paint.
, preferably 1 to 5% by weight, and the amount of the light stabilizer blended is 0.1 to 10% by weight, preferably 1 to 5% by weight, based on the resin solid content of the base paint or top clear paint. It is preferable to express it in weight %.

History--"L--Examples and comparative examples are given below to further clarify the present invention. Note that "part" and "1%" are basically based on weight.

1. Manufacturing example of solid coat paint (S-1) 50% alkyd resin solution (Wood 1) 140 parts 60% Kneepan 20SE (Wood 2) 50 parts Titanium oxide (Wood 3) 100 Kijirol/n-butanol (1/l) ) 17 with Solbetun #150, viscosity 25 seconds (Ford Cup A
Adjusted to 4/20"C). PVC is 19.
It was 5.

(Note 1) A 50% alkyd resin solution with a hydroxyl value of 85, an oil length of 31%, and a # value of 7.3, consisting of 1 mol of phthalic anhydride, 1 mol of trimethylolpropane, and o, s mol of coconut oil fatty acid.

(Note 2) Manufactured by Mitsui Toatsu Chemical ■, butanol-modified melamine resin (Note 3) Sakai Chemical Industry ■ TITONE R-(S
-2) 50% acrylic resin solution (Note 7) 140 parts 60% Kneepan 20SE (Note 2) 50 parts Titanium oxide (Note 3) 4.2 parts Carbon black (Note 4) 1.13 parts Oxide yellow (Note 5) 3.0 parts Organic Red Pigment (Note 6) 0.5 parts Cyanine Blue (Note 8) 6.2 parts (Note 4) Mitsubishi Chemical ■, Carbon Black MA-100B (Note 5) Titanium Industries ■, Mabiko Yellow XLO ( Note 6)
Dainichiseika Chemical Industry Co., Ltd., Corofine Red 6820 (Note 7) 15 parts of styrene, 42 parts of n-butyl acrylate, 23 parts of 2-ethylhexyl methacrylate,
50% acrylic resin solution (wood 8) consisting of 18 parts of hydroxy methacrylate and 2 parts of acrylic acid, Dainichiseika Kogyo ■, Lidmouth Cyanine Plue 52
2 to 40. Production example of top clear paint (T-1): Synthetic heptane of dispersion polymer liquid A 102 parts acetic acid n
-Butyl 8 moiety stabilizer (
Asahi Glass Co., Ltd.'s "LumiFlo 108 parts LF4006J weight average molecular weight approximately 19,000, fluorine atom content 30% by weight)" was charged into a flask and heated to reflux, and the following monomers and polymerization initiator were added dropwise over 3 hours. After time aging,
26 parts of n-butyl acetate was added.

Styrene 15 parts Methyl methacrylate 40 parts Acrylonitrile 30 parts 2-hydroxyethyl methacrylate 15 parts Tertiary-butyl peroxy 2-ethylhexanoate 1.5 parts The obtained liquid had a non-volatile content of 47%.

It was a milky-white, stable, low-viscosity polymer dispersion with a viscosity of A and a particle size of polymer particles (as measured by an electron microscope, hereinafter the same) of 0.15 u. No precipitation or coarse particles were observed even after being left at room temperature for 3 months.

(T-2): Synthetic heptane of dispersed polymer liquid B 102 parts acetic acid n
-butyl 8 parts 108 parts of the dispersion stabilizer of Example 1 were charged into a flask and heated to reflux, the following monomers and polymerization initiator were added dropwise over 3 hours, and after further aging for 2 hours, 26 parts of n-butyl acetate was added to the flask. Added part.

Styrene 15 parts Methyl methacrylate 17 parts Acrylonitrile 30 parts 2-hydroxyethyl methacrylate 15 parts Glycidyl methacrylate 20 parts Methacrylic acid
3 parts tertiary-butyl peroxy 2-ethylhexanoate 1.5 parts The resulting liquid was a stable, milky-white, low-viscosity polymer dispersion with a nonvolatile content of 46%, a viscosity of B, and a particle size of 0.12. Ta. 3 at room temperature
No precipitation or coarse particles were observed even after standing for several months.

(T-3): Introduction of a double bond into a dispersion stabilizer: 200 parts of Lumiflon LF400J (non-volatile content 50%, acid value 5, weight average molecular weight approximately 50,000, fluorine atom content 27%), glycidyl Methacrylate 0.8 part 4-
0.02 parts of tert-butylpyrocatechol and o and i parts of dimethylaminoethanol were added, and a reflux reaction was carried out for 5 hours to introduce a copolymerizable double bond into the dispersion stabilizer molecular chain.

The decrease in the resin acid value was suppressed to within 0.02, and the number of double bonds introduced per molecular chain was within one.

Synthesis of dispersed polymer liquid (C) Heptane 80 parts Acetic acid n-
8 parts of butyl and 130 parts of the above dispersion stabilizer were placed in a flask, heated to reflux, the following monomers and polymerization initiator were added dropwise over 3 hours, and after aging for 2 hours, 26 parts of n-butyl acetate was added. Ta.

Styrene 15 parts Methyl methacrylate 40 parts Acrylonitrile 30 parts 2-hydroxyethyl methacrylate 15 parts Tert-butyl peroxy 2-ethylhexanoate 1.5 parts The nonvolatile content of the obtained liquid was 47%, viscosity D, particle size 0 It was a stable low viscosity polymer dispersion with a milky white color of .18-. 3 at room temperature
No precipitation or coarse particles were observed even after being left standing for several months.

(T-4): 15 parts of styrene, 42 parts of n-butyl methacrylate, 2
- Copolymerize 23 parts of ethylhexyl methacrylate, 18 parts of hydroxyethyl methacrylate, and 2 parts of acrylic # in Kizilol using a polymerization initiator, azobisisobutyronitrile, with a heating residue of 50% and a solution acid value of 9.0. An acrylic resin solution having a solution viscosity of H and a weight average molecular weight of about 16,000 was obtained.

(T-5): (1) Preparation of dispersion stabilizer 40 parts of isobutyl acetate and 40 parts of toluene were heated to reflux, and the following monomers and polymerization initiator were added dropwise over 3 hours, followed by aging for 2 hours.

Styrene 10 parts Inbutyl methacrylate 69 parts 2-ethylhexyl methacrylate 10 parts 2-hydroxyethyl methacrylate 10 parts Methacrylic acid
1 part 2.2'-azobisisobutyronitrile 2 parts The obtained acrylic resin varnish had a nonvolatile content of 55%, a viscosity H, and a weight average molecular weight of about 16,000.

・Preparation of 2 non-aqueous dispersion 93 parts of heptane and 98 parts of the dispersion stabilizer obtained above were charged into a flask, heated to reflux, and the following monomers and polymerization initiator were added dropwise over 3 hours. Aged for 2 hours.

Styrene 15 parts Methyl methacrylate 40 parts Acrylonitrile 30 parts 2-hydrodiethyl methacrylate 15 parts tert-butylperoxy 2-ethylhexanoate 1.5 parts The obtained dispersion had a non-volatile content of 53%, a viscosity of B, and a polymer It was a milky white stable low viscosity polymer dispersion with a particle size of 0.2 to 0.3. No precipitation or coarse particles were observed in this dispersion even after the dispersion was stored at room temperature for 3 months.

(T-6): Dispersion stabilizer solution used in T-1 above per 85 parts of resin solid content in the dispersions or solutions obtained in (T-1) to (T-6) Add 15 parts (solid content) of 2) and further add 1 part per 100 parts of both resins.
10 parts of 0% ultraviolet absorber solution (Note 9) and 5 parts of light stabilizer (Note 10) were mixed, and the viscosity was 20 with Swasol #1000.
The viscosity was adjusted to ~40 seconds (Ford Cup #4/20°C) to obtain a clear paint.

In addition, a polyisocyanate compound (note) is added at a ratio of 1 mole of incyanate groups per 1 mole of hydroxyl groups in the resin contained in the dispersion or solution obtained in (T-1) to (T-6) above. Then, 10 parts of a 10% ultraviolet absorber solution and 0.5 parts of a light stabilizer (Note 12) were added per 100 parts of resin solid content, and then the viscosity was adjusted to 20 with cellosolve acetate.
-40 seconds (Ford Cup #4/20°C) to obtain a top clear paint.

Among the top clear paints obtained in this way, top clear paints containing amino resin (T-1
-AM) to (T-6-AM), top clear paint containing incyanate compound (T-1-NG), respectively.
O) ~ (T-6-NGO).

(Note 9): Dissolve Tinuvin 900 manufactured by Ciba Geigy in Kijiroll (Note 10): Tinuvin 144-10 manufactured by Ciba Geigy
% Kijirol solution (attention): Nippon Polyurethane Co., Ltd. Non-yellowing Brae C Noroku-Isoanate DC-2725 (Note 12) Nisankyo Co., Ltd. Sanol LS292 Automotive epoxyamide applied to mild steel plate subjected to degreasing and phosphate chemical treatment Prepare a coated plate coated with cationic electrodeposited primer and intermediate coat surfacer. Apply top clear paint wet (30g film thickness based on cured film) at 140℃.
Both coatings were cured simultaneously by heating for 0 minutes.

The coating process of these solid paints and top clear paints and the performance test results of the resulting paint films are shown in Table 1 below.

The performance test method for the coating film is as follows.

Accelerated weather resistance〉 QUV accelerated exposure test: Accelerated weather resistance tester manufactured by Q Pane 1 Test conditions Ultraviolet irradiation 16 hours/60℃ Water coagulation 8 hours 150℃ 1 cycle, 5000 hours (208 cycles)
After testing, the coating film was tested.

Gloss> The gloss before and after the accelerated weathering test was measured at a specular reflection angle of 60
' and 20°.

Surface tension The contact angle was measured using water and paraffin.

Painted surface condition> Judging by visual inspection.

■2 No abnormalities at all O: Discoloration of the meat is observed Δ: Some cracks, blisters, etc. occur ×: Many cracks, blisters, discoloration, etc. occur, poor image clarity> P G D (Portable Glass Dis
(interlayer adhesion) Cross-cut the painted surface to reach the substrate.

Adhesive cellophane tape was attached to the cut portion, and the state of the painted surface after being rapidly peeled off was visually observed.

■ = Almost no peeling of the paint film Δ: The paint film has peeled off a little ×: Hardness that prevents much paint film from peeling> Pencil for pencil scratch value test (Mitsubishi Uni) Impact resistance> DuPont impact tester 20 Place a coated plate with the coated side facing up on top of the striking center tip radius of 172 inches at ℃, drop 500g of fallen stone on the surface, and measure the maximum height (cm) without causing cracks or other abnormalities on the coated surface.Gazolin Resistance〉 Soaked in 8 stones super gasoline (20℃) for 24 hours.

Alkali resistance> 0, IN - 3 cc of sodium hydroxide (reagent) was dropped onto the coated surface, and the coated surface was observed after being left at 55° C. for 4 hours.

Procedural amendment (May 1988): L day 1, case description 1988 Patent Application No. 22957 2, name of the invention Top coating method 3, person making the amendment Relationship with the case Patent applicant residence Address: 33-1 Kanzaki-cho, Amagasaki-shi, Hyogo Prefecture, 1986-3
May 31st (Shipping date: April 28th, 1986) 5. Subject to amendment.

Claims (1)

[Claims] 1. When performing a solid color finish, in a finishing method in which a solid color is applied and then a transparent top clear paint is applied to the painted surface, the top clear paint contains fluoroolefin as an essential component,
The radically polymerizable monomer is soluble in the presence of a dispersion stabilizer consisting of an organic solvent-soluble fluorine-containing polymer having a weight average molecular weight of about 5,000 to about 120,000 and a fluorine atom content of about 1 to about 60% by weight. In an organic liquid in which the polymer formed by the radically polymerizable monomer is insoluble,
A top coating method characterized by using a curable coating material whose main component is a non-aqueous dispersion obtained by polymerizing the radically polymerizable monomer.