JPS6153366A - Coating of thick-coating sealer paint for mending - Google Patents

Abstract

PURPOSE:To carry out the coating of a thick-coating sealer paint for mending, easily, by compounding a specific polyol, a polyisocyanate, an inorganic pigment, an aliphatic hydrocarbon solvent, and a hydroxyl-containing solvent at specific ratios and applying the mixture. CONSTITUTION:(A) A polyol having a weight-average molecular weight of <=30,000, (B) a polyisocyanate, (C) an inorganic pigment, (D) an aliphatic hydrocarbon solvent and (E) a hydroxyl-free solvent other than the component D, are used as the components of the objective paint. The volume ratio of the components A, B and C to the components D and E is within the range defined by the points A1, B1, C1, D1 and E1, the molar ratio of the isocyanate group of the component B to the hydroxyl group of the component A (NCO/OH) is 1.5-0.5, and the volume ratio of the component C to the sum of the solid content of the resin of the components A and B is <=1.5. The mixture is applied to the substrate to achieve the coating of a thick-coating sealer paint for mending.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for applying a thick film repair sealer paint with reduced solvent permeability to an existing paint film, and more specifically, a method for applying a thick film repair sealer paint onto an existing paint film. The present invention relates to a method for applying a two-component urethane paint sealer that does not cause solvent swelling of the existing paint film and allows thick film coating.

[Conventional technology]

Many repair paints have been commercialized, mainly for automobile repair, and these can be classified into lacquer types and enamel types, mainly made of urethane. In the case of lacquer type paints, the thinners used in these paints are often ester-based or ketone-based solvents with strong dissolving power.

In the case of enamel type, a relatively mild solvent is used compared to lacquer type, but in this case retarder thinner, which has a slow evaporation rate, is often used to extend the finish and improve gloss.

[Problem that the invention seeks to solve]

An important point when repainting an automobile using such a refinishing paint is to quickly identify what type of old paint film is. In other words, if the old paint film is old and has never been repainted, the effect on the old paint film will be slight even if repainted using a relatively strong solvent thinner, but if the old paint film is If you have a paint film that has been repainted many times and has many layers, use lacquer thinner or tartar thinner! The paint may dissolve and swell, causing paint film distortion or, in severe cases, paint film lifting, resulting in complications such as having to completely peel off the old paint film and repaint it. A problem arises.

For this reason, the type of paint film the old paint film is based on the skin of the paint film, pencil hardness, how well it dissolves with lacquer thinner,
Alternatively, a method is generally used for identifying a change in luster, a change in luster due to heating, or dullness due to paper sanding, etc., either singly or in combination. However, even if these methods are used, it is not possible to identify the old paint film with 100% certainty, and identification tests often rely on sensory tests, which requires considerable skill. This is considered to be a major problem. In addition, some paint films that require repair painting include those that have numerous cracks, such as clear cracks in metallic paint films, and in such cases, the paint film must be completely sanded and then repaired. If the paint is not applied, "sucking" of the cracked area will appear on the painted surface, causing a problem of deterioration in the appearance of the paint film.

If both the process of identifying the old paint film and the process of completely sanding the old crank system paint film could be omitted or the man-hours reduced, it would be possible to eliminate labor costs, such as automobile refinishing, where labor costs account for more than 80 to 90 percent of the cost. In the industry, it is thought that significant total cost reduction benefits will arise. Conventionally, as a method to reduce the process of identifying old paint films, spray painting with a paint made by dissolving shellac-based resin in lower alcohol has been used to remove scratches, water marks, and bleeding from the paint film after the top coat. Techniques are being used to try to eliminate membrane defects.

However, this shellac type has a relatively high solution viscosity, making it difficult to spray paint with a high solid content concentration, and since the thinner is mainly a lower alcohol, the film forming properties during painting are poor, and only a low film thickness can be obtained. For this reason, when a top coat is applied after film formation, if the old paint film is a lacquer film with poor solvent resistance, the top coat film may become distorted, so the type of the old paint film still remains. Discrimination is required, and for this reason, its use is currently limited.

[Means for solving problems]

The present invention is intended to solve these problems, and has two
In liquid-type urethane paint sealers, the molecular weight of the polyol in the main ingredient is limited to a certain value or less, and as a solvent component in the paint, a poor solvent type aliphatic hydrocarbon solvent is used as the main solvent, and the remaining strong solvent type is used as the main solvent. By limiting the amount of hydroxyl-free solvent in the diluted paint to a certain volume percent or less, it is possible to spray paint with a higher solids concentration in the diluted paint without compromising the appropriate spray viscosity. Reduces solvent permeability to the membrane,
The present invention also provides a method for applying a thick film repair sealer paint that can reduce or omit the sasiding process and seal defects in old paint films.

The present invention provides a two-component urethane paint sealer in which the diluted paint composition includes the following components: a: a polyol with a weight average molecular weight of 30,000 or less b:
Polyisocyanate C: Inorganic pigment d: Aliphatic hydrocarbon solvent e: Consisting of a hydroxyl group-free solvent excluding an aliphatic hydrocarbon solvent, and consisting of component a, component B, and component C'
Point Ax ((a ~ component + c component) 60 : (a component) O: ( e component) 4
03° point B1 ((a component + b component + c component) 30:
(d component) O: (e component) 70), point ct ((a component + b component + c component) 10: (d component) 20: (
e component) 70], point D1 ((a component + b component + c component)
10: (d component) 90: (e component) 0] 1 point E
t[(a component + b component 10 C component) 60: (d component)
40: (e component) within the range surrounded by 0], a
The molar ratio of the isocyanate group (NCO) of the b component to the hydroxyl group (OH) of the component is NCO/OH=1.
5 to 0.5, and the total volume of component C is adjusted so that the volume ratio does not exceed 1.5 to the total volume of resin solids of components a and b. This is a method of applying a thick film type repair sealer paint.

It is a paint system that can be cured at room temperature or forced drying in a short period of time, such as automotive refinishing.

A base solution consisting of a polyol, an inorganic pigment, and a solvent; a curing agent consisting of a polyisocyanate and a solvent;
A so-called two-component urethane paint system that uses a diluting solvent is most suitable. The above components a, b, and c are film-forming components of such a two-component urethane paint sealer.

The resin system of the two-component urethane paint used in the present invention has excellent solubility in the solvent system within the volume composition range shown in Figure 1, and has excellent film forming properties and solvent resistance of the coating film. Any type of resin-based material can be used, but in the case of the polyol as component a, one having a weight average molecular weight of 30,000 or less can be used. If it exceeds 30,000, the viscosity of the system becomes too high.

An example of such a polyol as component a, in which a proper spray viscosity cannot be obtained when the film-forming solid content concentration is within the range of 10 to 6 volume percent, is an acrylic resin into which a long alkyl side chain is introduced.

Suitable materials include medium- and long-oil type alkyd resins, fatty acid-modified epoxy resins, and polyurethane polyol resins.

Examples of the polyisocyanate used as component b in the present invention include glycol adducts of toluene diisocyanate, diphenylmethane diisocyanate, and glycol adducts thereof.

Examples include glycol adducts of hydrogenated diphenylmethane diisocyanate, glycol adducts of hexamethylene diisocyanate or isocyanurates thereof, or biuret-reacted trimers thereof, and glycol adducts of isophorone diisocyanate or isocyanurates thereof.

These isocyanate compounds may be further used in combination or further modified to improve solubility in aliphatic hydrocarbon solvents.

Moreover, polyisocyanates other than those mentioned above can also be used as appropriate.

The mixing ratio of polyol and polyisocyanate is the molar ratio of the isocyanate group (NCO) of the polyisocyanate to the hydroxyl group (OH) of the polyol.
010) Adjust to a range of I = 1.5 to 0.5. If this molar ratio exceeds 1.5, the reaction rate of hydroxyl groups will increase, but the crosslinking density of the coating film will decrease, resulting in a decrease in the hardness, physical performance, etc. of the coating film, and the remaining free isocyanate groups will decrease. It is undesirable because it reacts with moisture in the air and causes foaming.

Furthermore, if this molar ratio is below 0.5, the coating film will not be sufficiently cured, and especially in the case of the present invention, which is limited to a polyol having a weight average molecular weight of 30,000 or less, such an effect is likely to occur, which is undesirable.

Any pigment can be used as the inorganic pigment that is component C, but in general, for sealer paints, for example, titanium white, mica, talc, kaolin, silica, pallite,
Calcium carbonate, red iron, carbon black, etc. are used, and in addition to these, anti-rust pigments such as zinc white, basic lead sulfate, basic lead chromate, zinc chromate, aluminum phosphate, etc. are also used as necessary. Zinc stearate is also used to improve the grindability of the coating film.

The amount of inorganic pigment used as component C is such that the total volume of p and organic pigment as component C is 1.5 in volume ratio to the total resin solid content of polyol as component a and polyisocyanate as component b. If this volume ratio exceeds 1.5, the mechanical properties of the coating film will deteriorate significantly, and even if a top coat is applied on such a coating film, it will cause so-called "swimming". Poor appearance is likely to occur, and the sharpness of the overcoat is reduced.

A curing catalyst is not necessarily required in the present invention, but if it is necessary to carry out the curing reaction at a low temperature and in a short time, the following catalysts may be used as film-forming components other than components a, b, and c. . Curing catalysts include amine compounds and metal compounds that are general urethane reaction catalysts, among them triethylamine, N-methylmorpholine, tetramethyl-1,3-butanediamine, triethylenediamine, 1,4-diaza-2, 2,2-bicyclooctane, N
, amine compounds such as N'-dimethylpiperazine, naphthenates or octolates such as manganese, lead, cobalt, zinc, copper, iron, cadmium, vanadium, tin, nickel, dibutyltin dilaurate, tin chloride, iron chloride, etc. These metal compounds can be used singly or in combination to obtain the desired hardenability.

In addition, we also have additives for coating surface adjustment, chicken properties imparting agents,
It can be used in the same way as general paints, such as wetting agents for pigment dispersion and dispersion stabilizing additives.

Component d and component C are solvents for diluting and dispersing the film-forming components. Examples of aliphatic hydrocarbon solvents that are component d used as the main solvent include hexane, heptane, octane, isooctane, nonane, trimethylhexane, decane, isodecane, Shellzol 70 (registered trademark of Shell Chemical Co., Ltd.), and Isopar. (Exxon Chemical Co., Ltd., registered trademark), and naphthenic hydrocarbon solvents such as cyclohexane, methylcyclohexane, ethylcyclohexane, cyclopentane, methylcyclopentane, decalin, etc. However, the latter naphthenic hydrocarbon solvent is most suitable as a solvent that has relatively good solubility for polyols, polyisocyanates, etc. and does not swell old paint films. Also, as long as the composition is within the composition range shown in FIG.
LAWS, HAWS, Shellzol 140, Schelzol 340 (all registered trademarks of Shell Chemical Co., Ltd.), Essonaphtha Nα], Essonaphtha Nα5. Esson naphtha N
There is no problem at all when using α6 (all registered trademarks of Exxon Chemical Co., Ltd.).

The hydroxyl group-free solvent of component C is a solvent that does not contain a hydroxyl group reactive with isocyanate groups other than aliphatic hydrocarbon agents, such as aromatic hydrocarbons, ketones, and esters.

There are ether solvents, etc. Among these hydroxyl group-free solvents, aromatic hydrocarbon solvents are relatively superior in solubility of polyol as component a and polyisocyanate as component b, and are less likely to cause solvent swelling of old paint films. It is most suitable as a hydroxyl group-free solvent.

Further, this hydroxyl group-free solvent does not necessarily have to be a single solvent, and two or more kinds of aromatic hydrocarbon-based, ketone-based, ester-based, ether-based, etc. solvents may be mixed. Examples of the aromatic hydrocarbon solvent include toluene, xylene, ethylbenzene, Tsurpez 8100 (registered trademark of Exxon Chemical Co., Ltd.), and Tsurpez #150 (registered trademark of Exxon Chemical Co., Ltd.). Examples of ketone solvents include acetone.

Examples include methyl ethyl ketone, diethyl ketone, methyl/thyl ketone, methyl isobutyl ketone, dibutyl ketone, methyl propyl ketone, diisobutyl ketone, methyl amyl ketone, cyclohexanone, and isophorone. Examples of ester solvents include methyl acetate, ethyl acetate, isopropyl acetate, orthopropyl acetate, isobutyl acetate, orthobutyl acetate, and amyl acetate. Although there are not many ether solvents that are of practical use, examples include tetrahydrofuran, jetoxyethane, diethylene glycol dimethyl ether, and ether ester solvents such as methyloxytol acetate, oxytol acetate, and butyloxytol acetate.

Stiffness and lifting phenomena in the coating film tend to occur when the volume ratio of the non-hydroxyl group-containing solvent, which is component C, in the coating material exceeds a critical amount.

The limit amount is polyol which is component A in the paint, polyisocyanate which is component B, inorganic pigment which is component C,
and 70 volume percent, preferably 50 volume percent, and most preferably 40 volume percent, based on the total volume of the solvent that is component d and component C. If the amount of the hydroxyl group-free solvent, which is component C, exceeds 70% by volume, the dissolving power of the entire solvent system becomes too strong and the old paint film tends to swell, which is undesirable.

In addition, in order to easily obtain a high film thickness with a small number of repeated coatings, and to improve the sealing properties for defective parts of the old coating film and the solvent barrier properties that prevent the penetration of solvents from the top coat, it is necessary to use component a. It is necessary to maintain the concentration of film-forming solids consisting of polyol, polyisocyanate as component B, and inorganic pigment as component C at 10 to 60 volume percent of the total volume of the paint diluted to spray viscosity. If the solid content concentration exceeds 60% by volume, the viscosity during coating becomes too high, making spray coating difficult unless special coating equipment such as hot spray is used. In the case of liquid sealer paints, the high solid content concentration tends to cause reactions between hydroxyl groups and isocyanate groups in the paint, which is undesirable because the usable time (pot life) of the diluted paint becomes extremely short. In addition, when the solid content concentration is below 10% by volume, the film thickness per coat becomes too thin, making it necessary to increase the number of coats until the desired film thickness is achieved, and for this reason, the coating process This takes too much time and runs counter to reducing the total cost of painting. The range of film-forming solids concentration in the present invention is preferably 20 to 6% by volume, most preferably 30 to 5% by volume.
0 volume percent.

Therefore, in the present invention, the volume ratio of the hydroxyl group-free solvent, which is component C, is the component a.
Polyisocyanate which is component b.

70 volume percent or less of the total volume of the inorganic pigment as component C, and the solvent as component d and C,
In addition, it is necessary to set the solid content volume ratio at the time of coating to 10 to 60 volume percent, and for this purpose, the respective volumes of the coating film forming components consisting of a component, b component, and C component, d component, and C component The composition ratio is defined by the area shown in the triangular coordinates of FIG. 1, that is, the point Al ((a component + component + C component) 60: (d component) O: (e component) 40).

Point B1 ((a component + S component + C component) 30: (d component) O: (e component) 70) 1 point Ct ((a component + b component + c component) 10: (d component) 20: (e component) )
703. Point os [(a component + b component + c component) 10: (
d component) 90: (e component) 0], point Et ((a component + b component + c component) 60: (d component) 40: (
It is necessary to adjust and apply the coating so that it falls within the range enclosed by e component) 0].

If the hydroxyl group-free solvent, which is component C, is 70% by volume or less, if an appropriate coating method is used, it will be possible to perform coating work without causing lifting, sagging, etc., which have been problems since usage. If the volume percentage of solids during painting is 60% by volume or less, painting can be performed without any trouble by selecting an appropriate spray gun, and if the solids content during painting is 10% by volume or more, the old If a suitable sandpaper is used for coating film treatment, it is possible to obtain sealing properties against paper grains, and it is also possible to easily secure a coating thickness sufficient to provide barrier properties against permeation of the top coat solvent when a top coat is applied.

Furthermore, in the present invention, the proportion of the hydroxyl group-free solvent, which is component C, is higher than that of the polyol, which is component a, the polyisocyanate, which is component b, the inorganic pigment, which is component C, and the total proportion of the solvent, which is component d and component C. 50 for capacity
It is preferable that the solid content is 20 to 60 volume percent at the time of coating, and for this purpose, the coating film-forming components consisting of the a component, the b component, and the C component, the d component, and the C component. The area ■, in which each capacitance composition ratio with and
component) 60: (d component) O: (e component) 40], point B2 [(a component + b component + c component) 50: (d component) O: (e component) 50], point C2 [(a component + b component) component + c component) 20: (d component) 30: (e component)
50], point D2 [(a component + b component + c component) 20:
(d component) 80 : (e component) 0] 1 point εx [(a
component + b component + c component) 60: (d component) 40:
(e component) 0] and apply the coating.

If the non-hydroxyl group-containing solvent, which is component C, is 50% by volume or less, even if restrictions on the coating method are relaxed, it will be possible to perform the coating work without causing lifting, sagging, etc., and the solid content at the time of coating will be 20%. If it is more than 1% capacity.

The restrictions imposed by sandpaper in the old paint film treatment are relaxed, and the paint film thickness necessary to obtain barrier properties can be easily obtained, making repair work easier.

Furthermore, in the present invention, the proportion of the hydroxyl group-free solvent, which is component C, is based on the total volume of the polyol, which is component a, the polyisocyanate, which is component b, the inorganic pigment, which is component C, and the solvent, which is component d, and component C. On the other hand, it is most preferable that the solid content is 40% by volume or less and the solid content at the time of coating is 30 to 50% by volume.
The area where each of the above capacity composition ratios is indicated by the triangular coordinates in FIG. 1, namely point A2 ((a component + b component + c component) 50
(d component) 10: (e component) 40], point D3 [(a
component + b component + c component) 30: (d component) 30:
(e component) 40], point C: 1 [(a component + b component + c
component) 30: (d component) 70: (e component) 0] 1 point D3 [(a component + b component + C component) 5 (1: (d component)
50: (e component) Adjust and paint within the range surrounded by 0].

When coating within the above range, there is no selectivity in coating method and spray gun, the limitations of sandpaper used in old coating treatments are significantly reduced, and the coating thickness required to obtain barrier properties is reduced. Furthermore, it is easily obtained and can significantly facilitate repair work.

The method for applying a sealer paint in the present invention consists of using a base solution in which a polyol as a component and an inorganic pigment as a component C are dissolved in an aliphatic hydrocarbon solvent as a component d and/or a hydroxyl group-free solvent as a component C. , a curing agent solution in which the polyisocyanate as component b is dissolved in an aliphatic hydrocarbon solvent and/or a hydroxyl group-free solvent as the d component, and an aliphatic hydrocarbon solvent and/or a hydroxyl group-free solvent as the d component. Painting is performed by mixing the base solution, curing agent solution, and diluted thinner in the range shown in Figure 1. In this case, air spray, airless spray, and electrostatic spray are generally used. Although this is the recommended method of painting, brush painting is also possible. The objects to be painted include fully flexural objects such as automobile parts and automobile bodies. Furthermore, by using an appropriate curing catalyst, it is possible to cure the coating at a temperature of 4 hours or more at room temperature by natural drying, or at a temperature of 40 to 40°C by baking.
A sufficiently cured coating film can be obtained at 60°C'e for 30 minutes or more.

[For production]

In the above coating, if the hydroxyl group-free solvent, which is component e, is 50 to 70% by volume, if only Shibuki coating is performed, problems such as lifting and stiffening will not occur.
When the solids content at the time of coating is 50 to 60% by volume, spraying can be performed without any problem by selecting an appropriate spray gun.

Also, if the solid content during coating is 10 to 20% by volume,
crack.

Sufficient sealing properties can be obtained against paper grains. Furthermore, even if the solid content at the time of coating is 10 to 20% by volume, a film thickness of 120 parts or more can be easily obtained with 4.5 coatings, so it has sufficient barrier properties against the solvent of the top coat. can get.

Therefore, if the ratio of each component is within the range of region I in FIG. 1, lifting, which has been a problem in the past, will occur.

Since no distortion or the like occurs, repair work can be simplified and shortened.

Next, the hydroxyl group-free solvent, which is component e, is added to
At 50% by volume, by combining the first coating with shibuki coating and the second and subsequent coatings with normal coating, coating can be performed without causing any lifting or sagging. Further, when the solid content during coating is 20 to 30% by volume, sealing properties against cracks and paper grains can be easily obtained. Solid content at the time of painting is 20-3
Even at 0 volume percent, a coating film thickness of 120 parts or more can be obtained after 3 to 4 coatings, and sufficient barrier properties against the solvent of the top coat can also be obtained.

Therefore, if the ratio of each component is within the range of area (3) in FIG. 1, it becomes easy to simplify and shorten the repair work.

If the aliphatic hydrocarbon solvent as component d is 40% by volume or less and the solid content during coating is 30 to 50% by volume, there will be no problems with spray workability, lifting performance, and sealing performance against cracks and paper grains. Since a coating film thickness of 120 parts or more can be easily obtained in just 2 to 4 coats, a sufficient barrier property against the solvent of the top coat can be easily obtained. Therefore, if the ratio of each component is within the range of area (3) in FIG. 1, it will be easiest to simplify and shorten the repair work.

Moreover, if NC010H (molar ratio) is within the range of 1.5 to 0.5, sufficient coating film performance can be obtained.

Further, if the pigment/binder volume ratio does not exceed 1.5, sufficient coating film performance can be obtained.

〔Effect of the invention〕

As explained above, 1. According to the coating method of the thick film type repair sealer paint of the present invention, in the two-component urethane paint sealer, a specific base ingredient and solvent are adjusted to have a specific composition ratio before painting. As a result, lifting of the repair paint film, which has traditionally been a problem in repair painting work, is avoided.
It can seal defects in the old paint film without causing wrinkles, etc. It can also sufficiently seal cracks, paper grains, etc., and it has a high barrier property against the solvent of the top coat, so it is suitable for repair work. It can be simplified and shortened.

〔Example〕

Below, synthesis reference examples, synthesis examples, base coating film creation examples, formulation examples,
Based on Examples and Comparative Examples, the present invention 1!11. Q: This will be explained in more detail, but the present invention is not limited thereto. In each example, parts indicate parts by weight unless otherwise noted.

Synthesis Reference Example 1 400 parts of xylene is charged into a glass 2Q flask equipped with a thermometer, a stirrer, a reflux condenser, and a monomer dropping device and heated to reflux temperature (about 140° C.). 200 parts of styrene, 49 parts of butyl acrylate, 165 parts of butyl methacrylate, 78 parts of 2-hydroxyethyl methacrylate, 5 parts of acrylic acid, and t-butyl peroxybenzoate (
A mixture of Perbutyl Z (registered trademark of NOF Co., Ltd.)
The mixture was kept at reflux temperature for 3 hours after the completion of the dropwise addition, and then 0.5 parts of t-butyl peroxybenzoate and 10 parts of xylene were mixed and added dropwise from the dropping device. After continuing the reaction by keeping the temperature at reflux for another 2 hours, 90 parts of xylene was added and the mixture was cooled to room temperature to obtain an acrylic co-coalescence solution A containing 50.0 weight percent of non-volatile components. The weight average molecular weight of this acrylic copolymer obtained using an APC molecular weight distribution analyzer i'' (HLC-802A manufactured by Toyo Soda Kogyo Co., Ltd.) is 33,400, and the Gardner viscosity of this resin solution at 25°C is Z, 2 more
Details of the six components whose specific gravity at 0° C. was 1.02 and their characteristic values are shown in A of Table 1.

Synthesis Examples 1 to 3 The same reaction operation as in Synthesis Reference Example 1 was performed using the same reaction apparatus to obtain acrylic copolymer solutions BD having the compositions and characteristic values shown in Table 1.

Synthesis Reference Example 2 194 parts of soybean oil fatty acid, 233 parts of phthalic anhydride, 69 parts of adipic acid, 146 parts of neopentyl glycol, and 135 parts of trimethylolpropane were mixed in a glass 2a equipped with a thermometer, stirrer, condenser, and dehydrator. After charging the flask and purging the system with nitrogen gas, heat to 160°C.
It takes about 1 hour to raise the temperature to 230℃, and then takes another 3 hours to raise the temperature to 230℃.
A dehydration reaction was carried out while raising the temperature to 230°C, and then, when the temperature reached 230°C, 50 parts of xylene was added little by little into the flask from the top of the condenser, and solvent stocking was continued.

The acid value of the varnish reached 4.5 approximately 3 hours after the start of solvent baking, so the synthesis was stopped, 468 parts of xylene was added, the mixture was cooled to room temperature, and an alkyd resin solution E containing 61.8% by weight of non-volatile components was prepared. I got it. The weight average molecular weight of this alkyd resin obtained by GPC was 8300, the Gardner viscosity of this resin solution at 25°C was TU, and the specific gravity at 20°C was 1.03. Details of the components and characteristic values are shown in Table 2.

Synthesis Examples 4 to 6 Using the same reaction apparatus as in Synthesis Reference Example 2, the same reaction operations were performed to obtain alkyd resin solutions F, G, and H having the compositions and characteristic values shown in Table 1.

Synthesis Example 7 562 parts of soybean fatty acid, 487 parts of Epicote 834 (registered trademark of Yuka Shell Epoxy Co., Ltd.) having an epoxy equivalent of 250, and 450 parts of xylene were charged into a glass 2Q flask equipped with a thermometer, a stirrer, and a condenser. After purging the inside of the system with nitrogen gas, the system was gradually heated, and after confirming that the inside of the system became transparent, 3 parts of triethylamine was added. after that.

The mixture was heated to reflux temperature, and the reaction was continued at reflux temperature for 4 hours.

At this time, the acid value of the varnish reached 0.4, so the reaction was stopped and the mixture was cooled to room temperature to obtain a resin solution of soybean oil fatty acid modified epoxy ester resin containing 70% by weight of non-volatile components. The weight average molecular weight of this soybean oil fatty acid modified epoxy ester resin obtained by GPC is 2200, the Gardner viscosity of this resin solution at 25°C is V, and the viscosity at 20°C
The specific gravity was 1.01. Details of the components and characteristic values are shown in Table 3.

Synthesis Examples 8 to 10 The same reaction procedure as in Synthesis Example 6 was carried out using the same reaction apparatus to produce soybean oil fatty acid modified epoxy ester resin solutions J and K having the composition and characteristic values shown in Table 3.

A benzoic acid-modified hydrogenated epoxy ester resin solution was also obtained.

Synthesis Example 11 Using the same reaction apparatus as Reference Example 2, 343 parts of soybean oil fatty acid, 173 parts of phthalic anhydride, 59 parts of adipic acid, 106 parts of neopentyl glycol, 180 parts of trimethylolpropane, and 600 parts of xylene were subjected to the same reaction. The operation was carried out to obtain an alkyd resin.

After that, remove the dehydrator and lower the temperature inside the flask to 50°C.
C., 39 parts of isophorone diisocyanate was gradually added to carry out a urethanization reaction, and when it was confirmed by IR that the isocyanate peak had disappeared, a polyurethane polyol resin solution M was obtained. The weight average molecular weight of this polyurethane polyol resin obtained by GPC was 6100, the Gardner viscosity of this resin solution at 25°C was T, and the specific gravity at 20°C was 1.03. Furthermore, this polyurethane polyol resin has an OHV of 96 and an AV of 4. Non-volatile components are 61
．． It was 5% by weight.

Base coating film creation example 1 After applying a repair paint (NFS725 urethane primer surfer 1 Nippon Rincid Mason Co., Ltd.) on a steel plate, it was baked at 80°C for 30 minutes to form a cured film with a coating thickness of 80μ. Next, 600 parts of acrylic copolymer solution A,
264 parts of rutile-type titanium oxide, 76 parts of xylene, and 60 parts of butyl cellosolve were mixed and dispersed in a sand grind mill to obtain a white enamel base with a grind gauge value of 10μ or less. Asahi Kasei Kogyo Co., Ltd., isopropyl alcohol 25% wet) 3
0 parts, 400 parts of methyl isobutyl ketone, and 300 parts of toluene were mixed and dissolved with a stirrer until it became transparent to obtain a nitrified cotton base.

Next, 500 parts of white enamel base, 156 parts of nitrified cotton base
and 10 parts of dibutyl phthalate were blended and uniformly dispersed with a stirrer to obtain a nitrocotton-modified acrylic lacquer white enamel.First, 500 parts of ethyl acetate, 170 parts of isopropyl alcohol, 105 parts of n-butyl alcohol,
and 225 parts of xylene to obtain a diluted thinner. Next, a diluted paint obtained by mixing 66.6 parts of the above nitrocotton-modified acrylic lacquer white enamel and 33.4 parts of the diluted thinner was used for the above repair. Apply on the paint film, 6
Force drying was performed at 0° C. for 1 hour to obtain a lacquer film with a coating thickness of 50 μm. Next, as a final topcoat, a polyurethane resin paint (Hiurethane Nα5000 Poight, Nippon Oil & Fats Co., Ltd.)
, registered trademark) was applied and baked at 80° C. for 30 minutes to obtain a coated plate with a cured film having a coating thickness of 50 μm. This painted board is 5
After leaving it at room temperature for a day, polish it with No. 400 wet sanding paper (manufactured by Nihon Kenshi Co., Ltd.) until it reaches the coating film of the above-mentioned repair paint.
A feather edge part was created.

The thus obtained painted plate was used as the base coating film 1 for the lifting test.

Base coating film creation example 2 After applying the repair paint (previously described - base paint film creation example 1) on a steel plate, it was baked at 80'C for 30 minutes to obtain a cured film with a coating thickness of 80μ. 486 parts of alkyd resin solution E, 264 parts of rutile titanium oxide, 190 parts of xylene, and 60 parts of butyl cellosolve were mixed, and sand grind mill dispersion was performed to obtain a white enamel base with a grind cage value of 10μ or less. , 500 parts of this white enamel base, 156 parts of the nitrified cotton base shown in Base coating film preparation example 1, and 10 parts of dibutyl phthalate were mixed and uniformly dispersed using a stirrer to obtain a nitrated cotton modified alkyd lacquer white enamel. First, 66.6 parts of this nitrocotton-modified alkyd lacquer white enamel and 33.4 parts of the diluted thinner shown in Basecoat Preparation Example 1 were mixed, and the resulting diluted paint was applied to the above repair paint. It was applied onto the film and force-dried at 60° C. for 1 hour to obtain a coated plate with a lacquer film having a coating thickness of 50 μm. After this painted board was left at room temperature for 5 days, it was polished down to the coating film of the repair paint using No. 400 wet sanding paper to create a feather edge portion. The obtained painted plate was used as the base coating film 2 for the lifting test.

Base coating film creation example 3 A cracked part was cut out from a scrapped car with significant paint film cracks, and a base chamber for crank sealing test @3
And so. Electron microscope (JSM-T20 manufactured by JEOL Ltd.)
) The depth of the crack obtained by measurement was 40 to 60μ,
The width of the crack was 30-50μ.

Base coating film creation example 4 After applying the repair paint (previously mentioned - base paint film creation example 1) on a steel plate, it was baked at 80°C for 30 minutes to obtain a cured film with a coating thickness of 80 μm. Apply the resin paint (previously mentioned - Base coat preparation example 1) and bake at 80°C for 30 minutes to obtain a coating thickness of 5.
A coated board with a cured film of 0μ was obtained. After leaving this painted board at room temperature for 5 days, dry sanding paper No. 80, No. 120, No. 1
Polish the surface with No. 80 (all manufactured by Nippon Shinshi Co., Ltd.),
This was used as base coating film 4 for the paper mark sealing test.

Formulation Example 1 3252 parts by weight of soybean oil fatty acid modified epoxy ester resin solution, 334 parts of rutile titanium oxide, 244 parts of talc,
7 parts of carbon black, 145 parts of Shell Bright Sol (aliphatic hydrocarbon solvent, registered trademark of Shell Chemical Co., Ltd.*), and 48 parts of xylene were mixed and dispersed in a sand grind mill to obtain a gray color with a grind gauge value of 30μ or less. Smith Joule N3300 for the 0th order that obtained the enamel base
(Isocyanurate of hexamethylene diisocyanate, registered trademark of Sumitomo Bayer Urethane Co., Ltd.) 522 parts,
326 parts of toluene, and 152 parts of methylcyclohexane
A curing agent solution was obtained by blending the following parts and dissolving them with a stirrer until the mixture became transparent. Next, 410 parts of toluene and 590 parts of methylcyclohexane were mixed to obtain a diluent thinner. Next, 76.79 parts of the above gray enamel base, 15.36 parts of hardener solution, 7.85 parts of diluted thinner, and dibutyltin were added. Formulation Example 1 in Table 4, in which a diluted paint was obtained by blending 0.02 part of dilaurate, shows the decomposed blending ratio of each component of this diluted paint. In this case, the NGO10H molar ratio is 1
．． 0, and since the first-order additivity is approximately established between the specific gravity of the soybean oil fatty acid modified epoxy ester resin solution, which is 1.02, the specific gravity of xylene, which is 0.86, and the specific gravity of the soybean oil fatty acid modified epoxy ester resin, , the specific gravity of soybean oil fatty acid modified epoxy ester resin was 1.08, the specific gravity of Sumidur N3300 (registered trademark of Sumitomo Bayer Urethane Co., Ltd.) was 1.16 (catalog value), and the specific gravity of paint raw material handbook (1.08) was obtained.
Using the specific gravity of rutile titanium oxide of 4.2, the specific gravity of talc of 2.6, and the specific gravity of carbon black of 1.8 shown in the 967 edition (Japan Paint Manufacturers Association), the specific gravity of methylcyclohexane was 0.79 (: catalog value). ], the specific gravity of Shell Bright Sol (registered trademark of Shell Chemical Co., Ltd.) of 0.80 (catalog value), and the specific gravity of toluene of 0.86 (Paint Raw Materials Handbook), the capacity on the attached triangular coordinates. Table 4 also shows the composition ratio, the volume ratio of the inorganic pigment as component C to the total resin solid volume, volume percentage, weight percentage, and viscosity in Ford cup #4 at 20°C.

Formulation Examples 2 to 25 By the same operation as in Formulation Example 1, diluted paints having the decomposed blending ratios of each component and characteristic values shown in Table 4 were obtained.

The conditions, target value standards, etc. in Table 5 are as follows.

Urethane sealer baking conditions: 40°C at 50'C temperature of coated object
Minute baking cure urethane sealer Treatment conditions: Polish down to 100μ with No. 320 dry abrasive paper Top coat: Polyurethane resin paint (example of base coating film creation above) Top coat baking conditions: No baking cure for 30 minutes at 80℃ temperature of coated object Mark: Non-applicable test item Spray - Standard value standards for workability, lifting property, sealing property and barrier property: × mark: Cannot be handled △ mark: Can be handled ◇ mark: No problem 0 mark: No problem Wider type 70 Spray gun: Manufactured by Iwata Painting Machine Co., Ltd., suction type, paint nozzle diameter 2.0, source pressure 3,5
kg/cm2 Wider 61 type spray gas spray gun machine industry Co., Ltd. g
, suction type, paint nozzle diameter 1.3mm, source pressure 3
, 5 kg/c+o2 Example 2 The results of testing each item using the paint of Formulation Example 1 and base coat 2 in the same manner as in Example 1 are shown in Table 5.
This is shown in Example 2.

Example 3 Using the diluted paint of Formulation Example 1 and base coat 3, the spray workability, one-time coating standard film thickness, and 120 to 150
We investigated the number of coats required for μ coating. In addition, after applying it on the cracked coating film and baking it for 40 minutes at the temperature of the object to be coated at 50°C, the coating film was polished down to 100μ, and a polyurethane resin coating (previously described - Base coating film preparation example 1) was applied. The crack marks were examined and the sealing properties against cracks were confirmed. These results are shown in Example 3 in Table 5.

Example 4 The results of testing each item using the diluted paint of Formulation Example 1 and base coat 4 in the same manner as in Example 3 are as follows:
It is shown in Example 4 in Table 5.

Examples 5-17. Comparative Examples 1 to 3 In Table 5, the results of testing each item in the same manner as in the Examples for improving the base coating film quality are shown in Examples 5 to 17 and Comparative Examples 1 to 3 in Table 5.

Example 18 Mixing example 1 of polished mild steel plate treated with No. 120 dry sanding paper
After baking the applied coating film at a temperature of 50°C for 40 minutes, polish it down to 100μ with No. 320 dry sanding paper, and remove the polyurethane resin paint (previously mentioned above). Coating film preparation example 1) was coated and baked at a temperature of 80°C for 30 minutes to determine adhesion, moisture resistance, and impact resistance.

The results of tests regarding gloss and overcoat clarity are shown in Example 18 in Table 6.

Examples 19.20. ° Comparative Example 4.5 The results of testing each item using the same procedure as in Example 18 are shown in Examples 19 and 20 and Comparative Examples 4 and 5 in Table 6.

Table 6. The test methods, evaluation criteria, etc. are as follows.

Test method Adhesiveness: 25 goblets of 4 m and 4 mm were made and a peeling test was performed using adhesive cellophane tape.

Moisture resistance = 50 soil 4℃, 12 in an atmosphere of 95% RH or higher
After 0 hours of exposure, the degree of blistering of the coating film was examined. Q is φ0. ; 20 or less bulges of n+m or less, × means φ1
．． 51 or more bulges are 20 or less.

Impact resistance: The height at which cracks or flakes occur is shown in cm using the Dupono method at 500 g and 172 inches.

Gloss: Examined with a 60 degree mirror surface.

D/IC Distinctness of Image (Distinctness of Image) by Dorigon Model D4'''IR-6F manufactured by Interlaboratory Co., Ltd.
f Colon age)" + value.

Standard value standards for spray workability: 0 mark: No problem,
], Suction type, paint nozzle diameter 2.0 mm, source pressure 3
, 5 kg/cm2 Example 21 Formulation Example 18 was applied onto a polished steel plate treated with No. 120 dry sanding paper, and the coating film was cured by baking at a temperature of 50°C for 40 minutes, and the coating film was cured with No. 320 dry sanding paper. After sanding down to 100μ and applying polyurethane resin paint (previously mentioned - Undercoat film preparation example 1), baking and hardening at a temperature of 80"C for 30 minutes, the adhesion, moisture resistance, impact resistance, gloss, The results of the test for overcoating sharpness are shown in Example No. 21 in Table 1.

Examples 22-25. Comparative Example 6 The results of testing each item through the same operations as in Example 21 are shown in Examples 22 to 25 in Table 7. This is shown in Comparative Example 6.

The points on Figure 41 explained above in the formulation examples, examples, and comparative examples are shown in Figure 2, and the numbers of the formulation examples, examples, and comparative examples corresponding to the points on Figure 2 are shown in Table 8. .

To explain the effects of the present invention in more detail with respect to the above formulation examples, examples, and comparative examples, the sealer paint of the present invention has no problems in spraying work as long as the viscosity during painting is within the range of 15 to 25 seconds. I know that. However, as shown in Formulation Example 24.25, when a polyol having a weight average molecular weight of 30,000 or more as component a is used,
Even if the solid content at the time of coating is 10% by volume or less, if the viscosity at the time of coating is 25 seconds or more, it becomes difficult to achieve high solidity and high build. Furthermore, since the solid content at the time of coating was 10% by volume, it also deviates from the area (2) in FIG. Therefore, in order to achieve spray workability, high solids differentiation, and high build, it is necessary that the weight average molecular weight of the polyol is 30,000 or less. As.

If the content of the non-hydroxyl group-containing solvent, which is component e, exceeds 70% by volume, lifting and sagging will occur in both regular and shibuki coatings, as in the past, and this will have an effect on simplifying and shortening repair work. In addition, as shown in Comparative Example 2 and Formulation Example 9, if the solid content at the time of painting is 60% by volume or more, the viscosity at the time of painting will be 50 seconds or more, and it will not work like the Wider 70 type spray gun. Even if a spray gun with a paint nozzle diameter of 2 IoIm is used, roughness, roughness, etc. will occur, making painting difficult and causing a significant drop in spray workability. Furthermore, as shown in [Comparative Example] and Formulation Example 12, when the solid content at the time of coating is less than 10% by volume, it takes 6 to 7% to obtain a film thickness of 100μ or more necessary to maintain barrier properties against top coating solvents. This goes against the desire to shorten the repair work, and the solvent component in the diluted paint is more than 90% by volume, and baking hardening and drying is required at a temperature of 50°C for more than 2 hours. Alternatively, after curing by baking at a temperature of 50°C for 30 minutes, setting is performed for an additional 5 hours or more to reduce the solvent component in the coating film, and unless polishing is performed, the paper grains cannot be sufficiently sealed. It became impossible,
This would go against the trend of shortening repair work. Therefore, if the area shown in Fig. 1 is not covered, lifting, sagging, etc., which are conventional painting defects, will occur, and repair work defects such as spray workability will be significantly reduced, and sealing of cracks and paper marks will occur. Causes decreased sexual ability.

It becomes impossible to simplify and shorten repair work.

However, as shown in Example 12 and Formulation Example 6, when the hydroxyl group-free solvent, component e, is at a volume percent of so-near o, problems such as lifting and stiffening will not occur if only Shibuki coating is performed. As shown in Example 13 and Formulation Example 8, when the solid content during coating is 50 to 60% by volume, the viscosity during coating will be 30 seconds or more. (manufactured by), it can be painted without any problem. Furthermore, when the solid content during coating is 10 to 20% by volume, the 180th paper size is completely sealed, the 1208(i') paper size can also be sealed, and even the 80th paper size can be sufficiently polished. This makes it possible to deal with it.

Furthermore, even if the solid content at the time of painting is 10 to 20% by volume, a film thickness of 120μ or more can be easily obtained after 4.5 coats, so sufficient barrier properties can be obtained against the solvent of the top coat. . Therefore, if it is within the region 1 in FIG. 1, lifting, bending, etc., which have been problems in the past, will not occur, making it possible to simplify and shorten the repair work.

Furthermore, as shown in Example 11 and Formulation Example 5, when the hydroxyl group-free solvent as component e is 40 to 50% by volume, the first coating is Shibuki coating, and the second coating is 40 to 50% by volume.
By combining the subsequent painting with normal painting, it becomes possible to paint without causing lifting, sagging, etc. In addition, as shown in Examples 14 to 16 and Formulation Example 10, when the solid content during coating is 20 to 30% by volume, cracks, #180 paper grains, and #120 paper grains are completely sealed. , No. 80 paper can also be sealed. Solid content at the time of painting is 20~
Even at 30% by volume, 120μ is achieved after 3 to 4 coatings.
Since the above coating thickness can be obtained, sufficient barrier properties against the solvent of the top coat can also be obtained. Therefore, if the area is within the area (3) in FIG. 1, the repair work can be easily simplified and shortened.

Furthermore, Examples 1 to 4. As shown in Formulation Example], Example 5゜6, Formulation Example 2, Examples 7 and 8, Formulation Example], Example 9.10, and Formulation Example 4, the hydroxyl group-free agent, which is component e, If the solid content is 30-50% by volume or less, there will be no problems with spray workability, lifting performance, sealing properties against cracks and paper marks, and the coating will be applied after 2-4 coats. Since a coating film thickness of 120μ or more can be easily obtained, sufficient barrier properties against the solvent of the top coat can be easily obtained. Therefore, if the area is within the area ■ in FIG. 1, the repair work #i can be simplified and shortened most easily.

In addition, NGOlof (for the molar ratio, Example 18,
Formulation example 14. As shown in Example 19, Formulation Example 15, Example 20, Formulation Example 16, Comparative Example 4, Formulation Example 1], Comparative Example 5, and Formulation Example 17, the NCO/OH molar ratio is less than 0.5, Alternatively, if it exceeds 1.5, the performance with respect to various physical properties will deteriorate. In particular, as shown in Comparative Examples 4 and 5, the adhesion was O/25. Moisture resistance is poor and impact resistance is significantly reduced to 15 cm. moreover.

For pigment/binder, Example 2], Formulation Example 18
．． Example 22, Formulation Example 19, Example 2], Formulation Example 20,
Example 24, Formulation Example 2], Example 25, Formulation Example 22. As shown in Comparative Example 6 and Formulation Example 23, when the pigment/binder (volume ratio) exceeds 1.5, performance with respect to various physical properties deteriorates. In particular, as shown in Comparative Example 6, the adhesion was O/
25. Moisture resistance is poor and impact resistance is significantly reduced to 15 cm.

As explained above, according to the coating method of the present invention, lifting and sagging of the repair coating film, which have conventionally been problems in repair coating work, do not occur, and cracks,
It can be seen that it sufficiently seals the papery areas and exhibits high barrier properties against the solvent of the top coat paint, resulting in a remarkable effect on simplifying and shortening the repair work.

[Brief explanation of drawings]

Figure 1 shows the triangular coordinates showing the volumetric composition ratio of the coating film-forming component and the solvent component, and Figure 2 shows the volumetric composition ratio of the coating film-forming component and the solvent component in Examples, Comparative Examples, and Formulation Examples. They are triangular coordinates. Agent Patent Attorney M

Claims (6)

[Claims] (1) In a two-component urethane paint sealer, the diluted paint composition consists of the following components: a: a polyol with a weight average molecular weight of 30,000 or less b:
Polyisocyanate c: Inorganic pigment d: Aliphatic hydrocarbon solvent e: Consisting of a hydroxyl group-free solvent excluding an aliphatic hydrocarbon solvent, and consisting of a coating film-forming component consisting of component a, component b, and component c, and component d. Point A_1 [(a component + b component + c component) 60: (d component) 0: (e component) 40], point B_1 [( a component + b component + c component) 30: (d component)
0: (e component) 70], point C_1 [(a component + b component +
c component) 10: (d component) 20: (e component) 70], point D_1 [(a component + b component + c component) 10: (d component)
90: (e component) 0], point E_1 [(a component + b component +
(component c) 60: (component d) 40: (component e) 0], and the isocyanate group (NCO) of component b is in a molar ratio of hydroxyl group (OH) of component a to NCO /OH is within the range of 1.5 to 0.5, and the total volume of component c is adjusted so that the volume ratio does not exceed 1.5 to the total volume of resin solids of components a and b. A coating method for a thick film type repair sealer paint, which is characterized by coating. (2) The volume composition ratio of the coating film forming components consisting of a component, b component, and c component, and the d component and e component is at point A_1 in Figure 1.
[(a component + b component + c component) 60: (d component) 0: (
e component) 40], point B_2 [(a component + b component + c component) 50: (d component) 0: (e component) 50], point C_2 [
(a component + b component + c component) 20: (d component) 30: (
e component) 50], point D_2 [(a component + b component + c component) 20: (d component) 80: (e component) 0], point E_1 [
(a component + b component + c component) 60: (d component) 40: (
The coating method according to claim 1, wherein the coating method is performed by adjusting the coating so that the component (e) falls within the range enclosed by 0]. (3) The volume composition ratio of the coating film forming components consisting of a component, b component, and c component, d component, and e component is at point A_2 in Figure 1.
[(a component + b component + c component) 50: (d component) 10:
(e component) 40], point B_3 [(a component + b component + c component) 30: (d component) 30: (e component) 40], point C_
3 [(a component + b component + c component) 30: (d component) 70
: (e component) 0], point D_3 [(a component + b component + c component) 50: (d component) 50: (e component) 0] A patent claim that adjusts and paints within the range surrounded by The coating method described in item 1 of the scope. (4) The coating method according to any one of claims 1 to 3, wherein component d is a naphthenic hydrocarbon solvent. (5) The coating method according to any one of claims 1 to 4, wherein component e is an aromatic hydrocarbon solvent. (6) Claims 1 to 5 include mixing a main ingredient mainly consisting of components a and c and a curing agent mainly consisting of component b, and diluting and mixing with a solvent consisting of components d and e. The coating method described in any of the paragraphs.