JPH1150005A - Production of urethane coating material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing 21 urethane coating material by which problems in settling or caking of a powdery filler, thickening or the like found in a conventional urethane coating material can be solved and the urethane coating material excellent in light resistance and stability can be obtained. SOLUTION: A liquid composition consisting essentially of a urethane prepolymer prepared from an active hydrogen-containing compound and an excessive amount of an aliphatic polyisocyanate and a polyaldimine in an amount of 60 pts.wt. is mixed with 40 pts.wt. fly ash as a powdery filler at the time of execution in a method for producing a urethane coating material utilized for waterproof materials for the roofs, wall surfaces or the like, flooring materials, paving materials, sealing materials, coating materials, paints or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to waterproof materials for roofs and walls, floor materials, paving materials, sealing materials, coating materials,
The present invention relates to a novel method for producing a urethane coating material used for a paint or the like.

[0002]

2. Description of the Related Art Urethane coating materials are excellent in mechanical strength, abrasion resistance, chemical resistance, weather resistance, and adhesion to a substrate, and can form a seamless coating film integrated with the substrate. It is widely used for waterproofing materials for roofs, waterproofing materials for wall surfaces, flooring materials, pavement materials, sealing materials, coating materials, paints, and the like. The urethane coating material includes, in addition to a urethane prepolymer having an isocyanate group (hereinafter referred to as a urethane prepolymer), a compound having an active hydrogen (hereinafter referred to as an active hydrogen compound), a powder filler, a catalyst, a stabilizer, a plasticizer, a thixotropic A composition comprising an agent, other additives, and the like is generally used. In particular, the urethane coating material contains about 20 to 50 parts by weight of a powder filler in the coating material, and is a main component of the urethane coating material. This powder filler plays an important role in improving the mechanical strength of the urethane coating material and improving the economics of the coating material.

[0003] These urethane coating materials include a one-pack type in which a urethane prepolymer obtained from a polyol which is an active hydrogen compound and an excess of polyisocyanate is cured by atmospheric moisture after construction, and a base material containing the urethane prepolymer. And a curing agent containing polyols are roughly classified into a two-pack type, which is mixed and cured at the time of construction. The two-pack type is easy to adjust the curing speed, but it is necessary to measure each component, measure each component, and stir and mix at the time of construction. Accordingly, the physical properties of the cured product may be deteriorated or the curing may be poor due to an error in the operation of the measurement and the stirring and mixing. On the other hand, the one-pack type is simple in construction method but has disadvantages such as slow curing and foaming. As a method for remedying this drawback, a latent curing agent such as enamine (British Patent No. 1575666), polyaldimine or polyketimine (British Patent No. 1064841, German Patent No. 3133969, JP-A-2-283710, JP-A-2-283710, No. 4,279,620) and a composition containing β-lactam (Japanese Patent Application Laid-Open No. 2-168) have been devised. Particularly, a composition containing a polyaldimine as disclosed in JP-A-4-279620 is excellent not only in curability but also in storage stability, and can be used for many products.

[0004]

Here, as the polyisocyanate used for the urethane coating material, tolylene diisocyanate or 4,4'-diphenylmethane diisocyanate, which is an aromatic polyisocyanate, is usually used. However, the urethane coating material using the above-mentioned conventional aromatic polyisocyanate gradually undergoes photo-oxidation when exposed to sunlight. This causes yellowing of the urethane coating film and deterioration of weather resistance. For this reason, in the prior art, in order to prevent such yellowing and deterioration, as a protective layer of the urethane coating material, an acrylic resin-based, fluororesin-based, silicone resin-based weather-resistant top coat is used. It was necessary as a top coat material. However, these top coats have to be applied after the urethane coating material has been cured, which increases the construction period and the number of steps during construction, and has been a factor in increasing construction costs. In addition, these topcoats are relatively expensive materials and have had significant economic problems along with rising construction costs.

[0005] In addition to the above, in the conventional urethane coating material, a liquid component and a powder filler, which are main components thereof, are usually mixed in advance. However, when a powder filler is contained in the liquid component, sedimentation and caking of the powder filler occur due to a change over time, and there is a serious problem in storage stability of the product. Until now, as a method of solving this sedimentation and caking, the addition of a thixotropic agent imparts structural viscosity to the sedimentation and
Preventing caking. However, when the thixotropic agent is added, the viscosity of the urethane coating material increases, and there has been a problem that workability at the time of handling deteriorates. In addition, thixotropic agents are more expensive than other formulations and are economically problematic. Furthermore, if the powder filler formulation is stored for a long period of time, it is not possible to completely prevent sedimentation and caking of the powder filler by any method other than the addition of a thixotropic agent. This has been a serious problem in product storage.

Further, in a one-pack type urethane coating material having a mechanism of moisture curing, the curing reaction progresses due to the influence of a small amount of moisture remaining in the powder filler, the viscosity increases with time, and finally the storage is completed. There is a major problem that the product inside becomes unusable, and no solution to this problem has been found to date, and a strong improvement has been demanded.

[0007]

Means for Solving the Problems The present inventors have intensively studied to solve these problems. As a result, it was found that a urethane coating material using a urethane prepolymer obtained from an active hydrogen-containing compound and an excess of an aliphatic polyisocyanate was stable without being subjected to photooxidation and could be used without a top coat. . Furthermore, to solve the problem of sedimentation and caking of the powder filler due to the inclusion of the powder filler in the raw material and the problem of the effect of moisture in the powder filler, the liquid component and the powder It has been found that a method in which the materials are separated until the time of construction and the two are mixed at the time of construction is a perfect method, and has been found to be more economical. Thus, the present invention has been completed. The present invention provides a novel urethane coating material obtained by mixing a liquid composition containing a urethane prepolymer and a polyaldimine obtained from an active hydrogen-containing compound and an excess of an aliphatic polyisocyanate with a powder filler at the time of construction. The present invention relates to a simple manufacturing method.

That is, the present invention provides the following (1) to (3)
Is provided. (1) A urethane coating material, wherein a liquid composition containing a urethane prepolymer and a polyaldimine obtained from an active hydrogen-containing compound and an excess of an aliphatic polyisocyanate, and a powder filler are mixed at the time of construction. Manufacturing method. (2) The method for producing a urethane coating material according to (1), wherein the powder filler has an average particle size of less than 100 μm. (3) The method for producing a urethane coating material according to (1) or (2), wherein the powder filler is fly ash.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail. The liquid composition of the present invention refers to a component of a liquid urethane coating material that does not contain a powder filler. All or part of the liquid composition contributes to the curing reaction,
Powder fillers do not contribute to the curing reaction. The liquid composition of the present invention essentially comprises a urethane prepolymer, polyaldimine, obtained from an active hydrogen compound and an excess of an aliphatic polyisocyanate. Known additives (curing catalyst, plasticizer, solvent, adhesion-imparting agent, colorant) may be added to the liquid composition for the purpose of adjusting the curability, the viscosity of the coating material, the coloring, the resistance, and the thixotropy. , Defoamers, stabilizers, thixotropic agents, etc.). Furthermore, it is also possible to add additives at the time of construction, instead of adding them to the liquid composition in advance.

The curing mechanism of the liquid composition is such that, when the composition is exposed to the atmosphere, the polyaldimine in the components dissociates the amine compound due to moisture in the atmosphere, and the amine compound reacts with the urethane prepolymer. To cure. Here, in a so-called conventional one-component moisture-curable urethane coating material that does not use a latent curing agent such as polyaldimine, carbon dioxide gas is generated at the time of curing, and thus problems such as foaming of the cured product are likely to occur. On the other hand, in the case of the present invention using polyaldimine, since the carbon dioxide gas is not generated at the time of curing, foaming of the cured product can be prevented. Furthermore, since the liquid composition of the present invention cures only with the liquid component, there is no danger of occurrence of curing failure due to an error in the operation of the measurement and stirring and mixing of the two components as seen in a two-component urethane coating material. .

The urethane prepolymer obtained from an active hydrogen compound and an excess of an aliphatic polyisocyanate used in the present invention refers to an aliphatic polyisocyanate and a polyol, an amine compound or the like having two or more molecules per known molecule. The compound is reacted with a compound having active hydrogen by a known method so that free isocyanate groups remain. That is, it is produced by reacting the aliphatic polyisocyanate with the active hydrogen-containing compound at 100 ° C. for several hours. The isocyanate group content is preferably 0.3 to 20.0% by weight, and a particularly preferred range is 0.5 to 15.0.
% By weight. 0.3% by weight of isocyanate group content
If it is less than the above, the hardness and mechanical strength of the coating material tend to decrease, and if it exceeds 20.0% by weight, the elongation of the coating material tends to decrease and it tends to become brittle, which is not preferable.

Examples of the aliphatic polyisocyanate used here include: 1) dicyclohexylmethane-4,4'-diisocyanate, isophorone diisocyanate, 2,5 (2,6)
-Bis (diisocyanatomethyl) bicyclo [2.2.
2] heptane (norbornane diisocyanate), hexamethylene diisocyanate, hydrogenated xylene diisocyanate, 1,4-cyclohexyl diisocyanate, 1-methyl-2,4-diisocyanato-cyclohexane, 2,4,4-trimethyl-1,6- Diisocyanates such as diisocyanato-hexane, 2) urethane-modified isocyanates of the above 1),
Isocyanurate modified product, carbodiimidated modified product,
And buret-modified products.

Further, the compound having two or more active hydrogens in one molecule as used herein refers to two or more hydroxyl groups, one or more amino groups, two or more mercapto groups, or two or more mercapto groups. May be a compound having a hydroxyl group and an amino group, or a compound having a hydroxyl group and a mercapto group, and specifically, for example, water, ethylene glycol, propylene glycol, glycerin, trimethylolpropane, pentaerythritol, sorbitol And polyhydric alcohols such as sucrose or aromatic amines such as aniline, tolylenediamine, p, p'-diamino-diphenylmethane, aliphatic amines such as ethylenediamine, ethanolamine, diethanolamine and the like, and alkanolamines described above. Compounds having two or more active hydrogens in one molecule Or polyether polyols obtained by addition polymerization of propylene oxide or propylene oxide and ethylene oxide to a mixture of these compounds, and polyetheramine compounds obtained by converting hydroxyl groups of the polyether polyols to amino groups , Polytetramethylene ether polyols, polycarbonate polyols, polycaprolactone polyols, polyester polyols such as polyethylene adipate, polybutadiene polyols, esters of higher fatty acids such as castor oil, polyether polyols or polyester polyols and vinyl Polymer polyols obtained by grafting a monomer, a compound obtained by copolymerizing a known ethylenically unsaturated monomer having one or more active hydrogens in one molecule, Ethers such as having a mercapto group.

The polyaldimine used in the present invention is represented by the following general formula (1):

[0015]

Embedded image Y-(— N ＝ CH—X) n (1) (wherein, X represents an aryl group having 6 to 15 carbon atoms. Y represents 2 to 15 carbon atoms and is divalent or 3 Divalent hydrocarbon group, or divalent or trivalent having a molecular weight of 70 to 6000
And a polyvalent polyoxyalkylene group. n represents 2 or 3. )

Basically, it is obtained by reacting an amine compound and an aldehyde described in detail below.

Examples of the amine compound used for producing the above-mentioned polyaldimine include: 1) ethylenediamine, 1,3-diaminopropane, tetramethylenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, decamethylenediamine, etc. Aliphatic diamine, 4,4′-diaminodicyclohexylmethane, isophoronediamine, bisaminomethylcyclohexane, 2,5- or 2,6-
Diamino methyl bicyclo [2.2.1] heptane, diaminocyclohexane, 3 (4), 8 (9) - bis (aminomethyl) - tricyclo [5.2.1.0 ^2.6] alicyclic diamines decane, Propylene oxide and / or aromatic diamine such as diaminodiphenylmethane, diaminodiphenylether, xylylenediamine, phenylenediamine, 3,5-diethyltoluene-2,4- or 2,6-diamine, water, ethylene glycol, propylene glycol, etc. Diamines such as polyoxyalkylenediamines obtained by converting hydroxyl groups of polyoxyalkylene glycols obtained by addition polymerization of ethylene oxide to amino groups,

2) 1,3,5-tris (aminomethyl)
The hydroxyl group of polyoxyalkylenetriols obtained by addition polymerization of propylene oxide and / or ethylene oxide to triamine such as benzene, 1,3,5-tris (aminomethyl) cyclohexane, glycerin, trimethylolpropane, etc. And triamines such as polyoxyalkylene triamines.

The aldehyde to be reacted with the above-mentioned amine compound includes, for example, benzaldehyde, o-tolualdehyde, m-tolualdehyde, p-tolualdehyde,
Examples include 4-ethylbenzaldehyde, 4-propylbenzaldehyde, 4-butylbenzaldehyde, 2,4-dimethylbenzaldehyde, 2,4,5-trimethylbenzaldehyde, p-anisaldehyde, and p-ethoxybenzaldehyde.

The polyaldimine represented by the above general formula (1) can be prepared by converting the above amine compound and the above aldehyde with a solvent such as toluene or xylene under an acid catalyst.
It is obtained by performing a azeotropic dehydration reaction and continuing the reaction until the distillation of water into the water droplet separator stops. The ratio of the above-mentioned amine compound to the above-mentioned aldehyde is suitably from 1 to 2 equivalents of the aldehyde to 1 equivalent of the amine.

The liquid composition used in the present invention is a urethane prepolymer obtained from a compound having two or more active hydrogens in one molecule and an aliphatic polyisocyanate, and a composition containing polyaldimine as a main component. The mixing use ratio of the polyaldimine and the urethane prepolymer is such that the polyaldimine reacts with moisture in the atmosphere and is hydrolyzed, and the number of amino groups of the amine compound generated by hydrolysis is included in the urethane prepolymer. To the number of isocyanate groups used (number of amino groups / number of isocyanate groups)
Is used at a ratio of 0.5 to 2.0, preferably 0.7 to 1.5.

If the ratio of the number of amino groups to the number of isocyanate groups is less than 0.5, the reaction between the excess isocyanate groups and the moisture in the atmosphere will generate carbon dioxide gas. The coating material tends to be easily foamed, and when the ratio exceeds 2.0, an excess amino group inhibits a polymer chain extension reaction of the coating material, and the coating material tends to be uncured, Not preferred.

The powder filler used in the present invention is one that is contained in the urethane coating material by at least 10% by weight and is a main component in the coating material.
Therefore, this does not include a powder additive or the like added in a small amount to the coating material for the purpose of coloring, imparting thixotropy, and the like.

Known powder fillers can be used. Specific examples of the powder filler include oxides (silica, alumina, zirconia, iron oxide, titanium oxide, magnesia, etc.), carbonates (calcium carbonate, magnesium carbonate, zinc carbonate, etc.), hydroxides ( Aluminum hydroxide, magnesium hydroxide, etc.), silicates (glass, kaolin, clay, talc, fly ash, mica, wollastonite, etc.), sulfates (calcium sulfate, barium sulfate, etc.), carbon (carbon black, graphite) ), Titanates (potassium titanate, barium titanate, etc.), nitrides (aluminum nitride, silicon nitride, etc.), carbides (silicon carbide, titanium carbide, etc.), phosphates (calcium phosphate, iron phosphate, etc.), Inorganic powder filler such as ferrite (barium ferrite, calcium ferrite), hard urethane, phenol Fat, such as polyvinyl chloride, an organic powder filler of various resin powders. These can be used alone or in combination of two or more.

The particle size of the powder filler affects the strength of the cured product. Therefore, when the particle size is large, the strength of the cured product tends to be small. Therefore, the particle size of the powder filler is preferably 100 μm or less, more preferably 50 μm or less.

The amount of the powder filler used is preferably from 10% by weight to 70% by weight, more preferably from 20% by weight to 60% by weight in the coating material. If the amount of the powder filler is less than 10% by weight in the coating material, the strength of the cured product will be low, and if the amount of the powder filler exceeds 70% by weight, the elongation of the cured product will be reduced and the physical property balance will be poor. There is a tendency.

In the present invention, since the powder filler is mixed at the time of application, it can be easily mixed and dispersed in the liquid composition, the rise in viscosity after mixing is small, and the cured product has high strength and high elongation. It is more desirable to select and use a suitable powder filler. Among them, fly ash is preferred. Fly ash is a spherical filler generated by the combustion of pulverized coal used in thermal power plants,
The fly ash can be easily mixed and dispersed in a liquid component, the viscosity increase after the mixing and dispersion is small, and the urethane cured product to which the fly ash is added is excellent in the balance of physical properties of strength and elongation. Fly ash is excellent and is particularly preferable as the powder filler used in the present invention.

The catalysts, stabilizers, plasticizers, adhesion promoters and other auxiliaries used in the present invention will be described.

Specific examples of the curing catalyst used in the present invention include, for example, dibutyltin dilaurate, lead octylate, stannas octoate, iron octoate,
Examples include metal salts of carboxylic acids such as bismuth octoate and bismuth neodecaate, tertiary amine compounds, imidazole compounds and the like.

Examples of the plasticizer used in the present invention include:
Specific examples include dioctyl phthalate, dibutyl phthalate, dilauryl phthalate, butylbenzyl phthalate, dioctyl phthalate, dioctyl adipate, diisodecyl adipate, diisodecyl phthalate, trioctyl phosphate, and chlorinated paraffin.

Examples of the solvent used in the present invention include:
Specifically, aromatic hydrocarbons such as toluene and xylene; aliphatic hydrocarbons such as hexane, heptane and octane; petroleum solvents from gasoline to kerosene fraction; esters such as ethyl acetate and butyl acetate; And ketones such as methyl ethyl ketone and methyl isobutyl ketone, and ether esters such as cellosolve acetate and butyl cellosolve acetate.

Examples of the adhesion-imparting agent include silane couplers and titanate couplers. Further, examples of the coloring agent include pigments (carbon black, titanium white, red iron oxide, shinkasha red, fast red,
Quinacridone red, cyanine blue, cyanine green, chrome green, ocher, titanium yellow, first yellow, etc.), and dyes.

Examples of the stabilizer include hindered phenol compounds, triazole compounds, hindered amine compounds and the like. Examples of the thixotropic agent include colloidal silica, fatty acid amide wax, aluminum stearate, surface-treated bentonite, polyethylene short fiber, and phenol resin short fiber. Examples of the antifoaming agent include a silicone compound and an acrylic compound.

In the urethane coating material using polyaldimine, since the curing reaction is caused by moisture in the air,
Curing proceeds mainly from the surface of the coating material. Accordingly, it takes a long time to cure the inside of the coating material in winter when the temperature and humidity are low. On the other hand, in the present invention, since water can be added to the liquid component and the powder filler at the time of construction, the addition of water causes the curing to proceed uniformly in the coating material, and furthermore, the amount of water added It is optionally possible to adjust the curing time by adjusting the.

In the present invention, known additives (curing catalyst, plasticizer, solvent, adhesive, etc.) are added to the liquid composition for the purpose of adjusting the curability, the viscosity of the coating material, the coloring, the resistance and the thixotropy. Imparting agents, coloring agents, defoaming agents, stabilizers, thixotropic agents, etc.). Furthermore, it is also possible to add additives at the time of construction, instead of adding them to the liquid composition in advance.

In the urethane coating material of the present invention, when mixing the liquid composition and the powder filler at the time of construction, it is desirable to use a stirrer for efficiently stirring and mixing in a short time. A commonly used propeller type hand stirrer (product example: Ryoubi Power Mixer) can also be used, but the stirring efficiency has been further improved. Simultaneous scraping and mixing of the can wall with a stirrer of the type that mixes with a small propeller stirrer at the same time as dropping (product example: Hard mixer 18LM type manufactured by Nippon Sosei Kogyo Co., Ltd.) or L-type stirring blade under reduced pressure Mixer (product example: Vacuum hard mixer UV-2 manufactured by Nippon Sosei Co., Ltd.)
0L type) is preferred.

The method for applying the urethane coating material of the present invention to a body such as a concrete substrate is not particularly limited, and can be carried out by a conventional method. For example, it may be performed by a method using an iron, a rake, a roller, a spray, or the like.

[0038]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto. In the examples, “parts” indicates “parts by weight”.

[Synthesis Example] [Synthesis of Polyaldimine] Synthesis Example 1 A reaction vessel equipped with a stirrer, a thermometer, a dropping funnel and a water separator was charged with 88 parts (2.0 parts) of tetramethylenediamine.
Equivalent), 0.1 part of formic acid and 500 parts of toluene, and mixed at room temperature under a nitrogen stream. After about 10 minutes, 300 parts (2.5 equivalents) of p-tolualdehyde was added to the dropping funnel for about 3 minutes.
It was dropped in 0 minutes. The reaction was continued for about 6 hours under reflux until water distillation stopped. The distilled water was 36 parts. Next, the external temperature was set to 150 ° C. Subsequently, toluene and unreacted p-tolualdehyde were distilled off. The reaction product (A-1) obtained after the distillation was 290 parts. In addition, as a result of measuring the infrared absorption spectrum of the obtained reaction product,
A characteristic absorption spectrum of -N = CH- was observed at 40 cm ^-1 . Polyaldimine A-1 has an amine value of 381 mg KO
H / g and a yellow liquid at room temperature.

[Synthesis of Urethane Prepolymer] Synthesis Example 2 13.4 parts of norbornane diisocyanate (manufactured by Mitsui Toatsu Chemicals, Inc., trade name: NBDI) as an aliphatic polyisocyanate in a reaction vessel equipped with a stirrer and a thermometer. Polyoxypropylene triol (Mitsui Toatsu Chemical Co., Ltd.,
Trade name: Mitsui polyol MN-5000, molecular weight 500
0) 45.5 parts, polyoxypropylene diol (trade name: Mitsui Polyol Diol-, manufactured by Mitsui Toatsu Chemicals, Inc.)
41.1 parts were inserted into the reaction mixture at 100 ° C. for 10 hours under a nitrogen stream to obtain urethane prepolymer P-1 (terminal NCO group was 3.0% by weight).

Synthetic Example 3 In the same manner as in Synthetic Example 2, isophorone diisocyanate (trade name, manufactured by Huls, trade name:
IPDI) 14.5 parts, polyoxypropylene triol (manufactured by Mitsui Toatsu Chemicals, Inc., trade name: Mitsui Polyol M)
N-5000), 44.9 parts, and polyoxypropylene diol (Mitsui Toatsu Chemical Co., Ltd., trade name: Mitsui Polyol Diol-3000), 40.6 parts, are inserted, and reacted at 100 ° C. for 10 hours under a nitrogen stream. As a result, urethane prepolymer P-2 (terminal NCO group was 3.0% by weight) was obtained.

Comparative Synthesis Example 1 In the same manner as in Synthesis Example 2, 2,4-tolylene diisocyanate, an aromatic polyisocyanate (trade name: Cosmonate T-100, manufactured by Mitsui Toatsu Chemicals, Inc.)
4 parts and polyoxypropylene triol (trade name: Mitsui Polyol MN-5000, manufactured by Mitsui Toatsu Chemicals, Inc.) 4
6.5 parts, polyoxypropylene diol (manufactured by Mitsui Toatsu Chemicals, Inc., trade name: Mitsui Polyol Diol-300)
0) Urethane prepolymer P-3 from 42.1 parts
(The terminal NCO group was 3.0% by weight).

Example 1 Example 1 72.4 parts of urethane prepolymer P-1; 6.9 parts of polyaldimine A-1; 10 parts of DOP; 10 parts of xylene; 0.2 parts of octylic acid; -75 (manufactured by Ciba-Geigy) and 0.5 part of a liquid composition G-1
Was adjusted. The resulting liquid composition G-1 showed no precipitation of solid components, no separation of liquid, and the like after storage at room temperature for one year, and a slight increase in viscosity. Next, the liquid composition G-1
In 60 parts, 40 parts of fly ash (trade name: Onoda Super Flow SF- # 5000, average particle size: 8 μm, manufactured by Chichibu Onoda Co., Ltd.) and gray toner (trade name: FTR toner manufactured by Dainichi Seika Kogyo Co., Ltd.) 3) was added, and the mixture was stirred and mixed under reduced pressure for 10 minutes using a vacuum hard mixer model UV-20L manufactured by Nippon Sosei Co., Ltd. to obtain a product. The viscosity of the product after mixing was 6,800 cps (25 ° C.), and the workability was good for ironing and the like. The physical properties of the cured product of the product were a hardness of 66 (Shore A), a tensile strength of 29 kgf / cm ² , and a good balance of physical properties as a urethane coating material.

When the obtained cured product was irradiated with a sunshine weatherometer for 500 hours using an accelerated exposure tester, no crack, occurrence of chalking, discoloration, etc. were observed in the cured product, and the tensile strength after irradiation for 500 hours was obtained. Showed only a slight decrease (retention rate 98%) as compared to before irradiation. After storing the liquid composition G-1 at room temperature for one year,
A cured product was produced in the same manner, but there was only a slight decrease in physical properties, and no problem was observed in use.

Example 2 72.4 parts of urethane prepolymer P-2, 6.9 parts of polyaldimine A-1, 10 parts of DOP, 10 parts of xylene, 0.2 parts of octylic acid, tinuvin B-75 (Ciba Geigy) 0.5 parts of a liquid composition G-2
Was adjusted. The resulting liquid composition G-2 showed no precipitation of solid components, no separation of liquid, and the like after storage at room temperature for one year, and a slight increase in viscosity. Next, the liquid composition G-2
In 60 parts, 40 parts of fly ash (trade name: Onoda Super Flow SF- # 5000, average particle size: 8 μm, manufactured by Chichibu Onoda Co., Ltd.) and gray toner (trade name: FTR toner manufactured by Dainichi Seika Kogyo Co., Ltd.) 3) was added, and the mixture was stirred and mixed under reduced pressure for 10 minutes using a vacuum hard mixer model UV-20L manufactured by Nippon Sosei Co., Ltd. to obtain a product. The viscosity of the product after mixing was 6,700 cps (25 ° C.), and the workability was good for ironing and the like. The physical properties of the cured product of the product were a hardness of 66 (Shore A), a tensile strength of 30 kgf / cm ² , and a good balance of physical properties as a urethane coating material.

When the obtained cured product was irradiated with a sunshine weatherometer for 500 hours using an accelerated exposure tester, no cracks, occurrence of chalking, discoloration, etc. were observed in the cured product, and the tensile strength after irradiation for 500 hours was obtained. Showed only a slight decrease (retention rate: 95%) as compared to before irradiation. After storing the liquid composition G-2 at room temperature for one year,
A cured product was produced in the same manner, but there was only a slight decrease in physical properties, and no problem was observed in use.

Comparative Example 1 72.4 parts of urethane prepolymer P-3, 6.9 parts of polyaldimine A-1, 10 parts of DOP, 10 parts of xylene, 0.2 parts of octylic acid, Tinuvin B-75 (Ciba Geigy) 0.5 parts) and the liquid composition G-3
Was adjusted. Next, fly ash (manufactured by Chichibu Onoda Co., Ltd., trade name: Onoda Super Flow SF- # 5000, average particle size 8 μm) is added to 60 parts of the liquid composition G-3.
And 3 parts of gray toner (manufactured by Dainichi Seika Kogyo Co., Ltd., trade name: FTR toner), and stirred and mixed under reduced pressure for 10 minutes using a vacuum hard mixer UV-20L manufactured by Nippon Sosei Co., Ltd. A coating material was obtained, and the material was cured to form a cured product. The physical properties of the cured product were as follows: a hardness of 65 (Shore A) and a tensile strength of 31 kgf / c.
m ² .

When the obtained cured product was irradiated for 500 hours with a sunshine weatherometer using an accelerated exposure tester, cracks and chalking were observed in the cured product.
The tensile strength after irradiation for 00 hours was significantly reduced (retention rate: 56%) as compared with that before irradiation. Table 1 below shows the measurement results of the physical properties and the like measured in the above Examples and Comparative Examples.

[0049]

[Table 1]

[0050]

According to the present invention, a liquid composition containing a urethane prepolymer and a polyaldimine obtained from an active hydrogen-containing compound and an excess of an aliphatic polyisocyanate and a powder filler are mixed during construction, Urethane coating material excellent in light stability such as yellowing and weather resistance can be obtained, and furthermore, sedimentation and caking of powder filling material which can be seen in urethane coating material mixed with conventional powder filling material in advance,
Problems such as thickening can be solved. Further, the liquid composition and the filler of the present invention can be stored for a long period of time. In addition, since the top coat (overcoating material) of the urethane coating material used conventionally is not required, these expensive materials are not required in combination with the omission of the process at the time of construction and the shortening of the construction period, and the construction cost is greatly reduced. It becomes possible.

Claims (3)

[Claims] 1. A urethane, wherein a liquid composition containing a urethane prepolymer and a polyaldimine obtained from an active hydrogen-containing compound and an excess of an aliphatic polyisocyanate, and a powder filler are mixed at the time of construction. Manufacturing method of coating material. 2. The method for producing a urethane coating material according to claim 1, wherein the average particle diameter of the powder filler is less than 100 μm. 3. The method for producing a urethane coating material according to claim 1, wherein the powder filler is fly ash.