JP2003019459A - Method of manufacturing stain-resistant resin plate, and stain-resistant resin plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide method of manufacturing a stain-resistant resin plate having a stain-resistant coating film having excellent adhesive property and to provide the stain-resistant resin plate. SOLUTION: In the method of manufacturing the stain-resistant resin plate, an urethane setting type under coating material is applied on a resin plate to form an under coating film and then an urethane setting type top coating material containing a silicate compound is applied thereon to form a stain- resistant top coating film. The stain-resistant resin plate is obtained by the method of manufacturing the stain-resistant resin plate.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a stain resistant resin plate and a stain resistant resin plate.

[0002]

2. Description of the Related Art Since a vehicle's exhaust gas is directly exposed on a highway, sound-insulating walls, median strips, toll booths, etc. are easily contaminated. In particular, transparent resin plates such as polycarbonate plates and acrylic plates used for part of the sound insulation walls that are transparent in the landscape and part of the walls of the toll booth that act as windows are transparent due to stains over time. It had to be washed frequently to lose.

By the way, a method for forming a coating film excellent in stain resistance by incorporating a silicate compound into a coating material is being developed, and these are, for example, WO94 / 06.
870, WO96 / 262458, and JP-A-10-72569. The stain resistance of such a coating film is exhibited when the silicate compound localized on the surface undergoes a hydrolysis reaction to produce silanol and the coating film becomes hydrophilic.

Therefore, it is considered to apply a stain-resistant coating film on the resin plate, but the adhesion between the resin plate and the stain-resistant coating film is insufficient, and the coating film peels off over time. For,
There was a problem in terms of durability.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for producing a stain-resistant resin plate having excellent stain-resistant coating film adhesion and a stain-resistant resin plate.

[0006]

According to the present invention, a urethane curable undercoat paint is applied to a resin plate to form an undercoat coating film, and then a urethane curable topcoat paint containing a silicate compound is applied. A method for producing a stain resistant resin plate, which comprises forming a stain resistant top coating film. Here, it is preferable that the main resin of the urethane curable top coating material is a hydroxyl group-containing fluororesin. Further, the silicate compound is preferably a fluorine atom-containing silicate compound. Further, the resin plate is preferably a transparent resin plate, and the urethane-curable undercoat paint and the urethane-curable topcoat paint are preferably clear paints.

Further, the present invention is a stain resistant resin plate obtained by the above method for producing a stain resistant resin plate.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The first step of the method for producing a stain resistant resin plate of the present invention is to apply a urethane curable undercoat paint to a resin plate to form an undercoat film. The resin plate is not particularly limited, and examples thereof include a polycarbonate plate and an acrylic plate. Such a resin plate may be subjected to various surface treatments. It may be opaque, but especially when it is used for walls that act as windows of toll booths on expressways,
It is preferably transparent.

The urethane-curable undercoat paint is not particularly limited, and examples thereof include those containing a hydroxyl group-containing resin as a main resin and a polyisocyanate compound as a curing agent. The hydroxyl group-containing resin is not particularly limited, and examples thereof include a hydroxyl group-containing acrylic resin well known by those skilled in the art, a polyester resin, a fluorine-based resin, and the like. It is preferably a resin.

The resin solid content hydroxyl value of such a hydroxyl group-containing resin is not particularly limited, but from the viewpoint of curability and flexibility of the resulting coating film, it is preferably 20 to 200, and 30 to 150. It is more preferable that there is. The number average molecular weight is not particularly limited, but from the viewpoint of curability and coating workability, it is 1000 to 1
It is preferably 00000, 1500 to 3000
It is more preferably 0. The number average molecular weight is GPC (gel permeation chromatography).
Etc. can be measured and determined by a method well known by those skilled in the art.

Specific examples of the polyisocyanate compound include 2,4-tolylene diisocyanate, diphenylmethane-4,4'-diisocyanate,
Diisocyanates such as xylylene diisocyanate, isophorone diisocyanate, lysine methyl ester diisocyanate, methylcyclohexyl diisocyanate, trimethylhexamethylene diisocyanate, hexamethylene diisocyanate, n-pentane-1,4-diisocyanate and norbornene diisocyanate, and trimers of these. Examples thereof include adducts and burets, polymers of these polymers having two or more isocyanate groups, and triisocyanates such as lysine triisocyanate.

The content ratio of the hydroxyl group-containing resin to the polyisocyanate compound is a molar ratio of the hydroxyl group of the hydroxyl group-containing resin to the isocyanate group of the polyisocyanate compound from the viewpoint of the curability and performance of the resulting coating film. (OH / NCO) is preferably 2.0 to 0.2, and more preferably 1.3 to 0.7.

Further, the urethane-curing type undercoating material contains, in addition to the above-mentioned components, a thickener, a surface conditioner, a film-forming aid, an ultraviolet absorber, an antioxidant, a curing catalyst, a hydrolysis catalyst, a silane coupling agent. , Flame retardants, antistatic agents, rust inhibitors, etc.
Various ingredients well known to those skilled in the art can be included.

The urethane-curable undercoat paint is
It may contain a color pigment, an extender pigment, and a pigment dispersant, but when the resin plate is transparent, the urethane curable undercoat paint is preferably a clear paint.

Such urethane-curable undercoat paint is
From the viewpoint of pot life, the above-mentioned main resin and, if necessary, other components that do not react with the main resin are used as a coating liquid, and the above-mentioned curing agent and, if necessary, other components that do not react with the curing agent are cured. It is preferable to store the solutions separately and mix them just before use.

The application of the urethane-curable undercoat paint is not particularly limited, and it can be performed by a method such as spraying, brushing, roller, curtain flow, roll, dip or the like. The coating film thickness is not particularly limited and is, for example, 10 to 50 μm.

After coating, it is appropriately dried to form an undercoat coating film. The drying condition is not particularly limited, and is, for example, standing at room temperature. In addition, the normal temperature is about 5 to about 40 ° C.
Is.

The second method of manufacturing the stain resistant resin plate of the present invention
The step of, on the undercoat coating film obtained in the first step,
A urethane-curable top coating composition containing a silicate compound is applied to form a stain-resistant top coating film.
The state of the undercoat coating film when the urethane-curable topcoat paint is applied is not particularly limited, but the undercoat coating film is preferably dry to the touch. After the above application,
The time to dry to the touch is, for example, 2 to 5 hours.

The urethane-curable topcoat paint is not particularly limited, and the same hydroxyl group-containing resin as the urethane-curable undercoat paint can be used as a main resin, and a polyisocyanate compound can be used as a curing agent. From the viewpoint, it is preferable that the main resin is a hydroxyl group-containing fluororesin. Examples of the hydroxyl group-containing fluororesin include fluoroolefin copolymers. Such fluoroolefin copolymers that are commercially available include Zeffle series (manufactured by Daikin Industries, Ltd.), Lumiflon series (manufactured by Asahi Glass Co., Ltd.), Cefral Coat series (manufactured by Central Glass Co., Ltd.), Fluoronate series ( Examples include Dainippon Ink and Chemicals, Inc., Zaflon series (manufactured by Toagosei Co., Ltd.) and the like.

From the viewpoint of the curability and performance of the resulting coating film, the content ratio of the hydroxyl group-containing fluororesin and the polyisocyanate compound is such that the hydroxyl group of the hydroxyl group-containing resin and the isocyanate group of the polyisocyanate compound are Molar ratio (OH / NCO) is 2.0-0.2
Is preferable, and 1.3 to 0.7 is more preferable.

The silicate compound has the general formula (1):

[0022]

[Chemical 1]

A compound and / or a condensate represented by The above n represents the degree of polymerization and is an integer of 1 to 100. From the viewpoint of volatilization and resin handling, 2
It is preferably -100 and more preferably 4-20. When n is 2 or more, examples of the shape of the silicate compound include a linear shape, and other shapes include a branched chain shape, a cyclic shape, and a three-dimensional polymer. .

In the formula, R ¹ is the same or different,
Any of which is an organic group having 1 to 9 carbon atoms, which may contain a nitrogen atom, an oxygen atom, a fluorine atom and / or a chlorine atom,
Alternatively, it is a hydrogen atom, and from the viewpoint of dispersion stability and hydrolyzability, an organic group having 1 to 6 carbon atoms is preferable. When the number of carbon atoms is out of the above range, the dispersion stability is lowered, or the low stain resistance of the obtained coating film is lowered.

Specifically, as such, Si
(OCH ₃ ) ₄ , Si (OC ₂ H ₅ ) ₄ and condensates and co-condensates thereof, etc. may be mentioned. Commercially available products include MKC silicate MS56 and MKC silicate MS51 (all are manufactured by Mitsubishi Chemical Corporation. Examples thereof include methyl silicate compound manufactured by Mitsui Chemical Co., Ltd.) and ethyl silicate 40 (ethyl silicate compound manufactured by Colcoat Co., Ltd.). Further, the organic group of these alkyl silicates may be partially substituted with the alcohol compound having R ¹ described above.

Specific examples of the alcohol compound include propyl alcohol, isopropyl alcohol, n
Examples thereof include alkyl alcohols such as -butyl alcohol and sec-butyl alcohol, and ether alcohols such as butyl cellosolve, methoxypropanol and ethoxypropanol.

From the viewpoint of low stain resistance of the resulting coating film, it is preferable that at least one of the R ¹ 's contains a fluorine atom, and all R ¹ 's further contain a fluorine atom. preferable.

In the above silicate compound, its stability
From the viewpoint of the durability and the stain resistance of the resulting coating film, the above R¹age
Specifically, CH₂-CF₂-R or CH₂CH₂-C
F₂-R (wherein R is a nitrogen atom, an oxygen atom, a fluorine atom)
And / or an organic group optionally containing a chlorine atom, or
Is a hydrogen atom), and the carbon number of R is
Is more preferably 1 to 3. Something like this
Specifically, CH ₂CF₃, CH₂CF₂CF₃, C
H₂(CF₂)₂CF₃, CH₂CH₂(CF₂)₃CF₃, C
H₂(CF₂)₂H, CH₂(CF₂)₃H, CH₂(CF₂)
_FourH etc. can be mentioned.

When R ¹ contains a fluorine atom,
The content of fluorine atoms contained in the silicate compound is preferably 15% by weight or more, more preferably 30 to 50% by weight. If the content is less than 15% by weight, the resulting coating film may have insufficient stain resistance.

Examples of such a fluorine atom-containing silicate compound include Si (OCH ₂ CF ₂ CF ₃ ) ₄ Si (OCH (CF ₃ ) ₂ ) ₄ Si (OCH ₂ CF ₂ CF ₂ H) ₄ Si (OCH ₂ C ₄ F ₈ H) ₄ Si (OCH ₂ CF ₂ CF ₃ ) ₂ (OCH ₃ ) ₂ Si (OCH (CF ₃ ) ₂ ) ₂ (OCH ₃ ) ₂ Si (OCH ₂ CF ₂ CF ₂ H) ₂ ( _{OCH 3) 2 Si (OCH 2} CF 2 CF 3) 2 (OH) and the like can be mentioned ₂ and its condensates and cocondensates, those that are commercially available, Zeffle GH110 (Daikin Industries, Ltd.) Can be illustrated.

The content of the silicate compound in the urethane curable top coating composition is 0.1 to 80 parts by weight, and 1 to 50 parts by weight based on 100 parts by weight of the resin solid content of the hydroxyl group-containing resin. Preferably there is. When the content is less than 0.1 part by weight, the resulting coating film may have insufficient stain resistance, and when it exceeds 80 parts by weight, the curability and appearance of the obtained coating film may be deteriorated. There is a fear.

Further, the above urethane-curable topcoat paint, in the same manner as the above-mentioned urethane-curable undercoat paint, besides the above-mentioned components, a thickener, a surface conditioner, a film-forming aid, an ultraviolet absorber,
It may contain various components well known by those skilled in the art, such as an antioxidant, a curing catalyst, a hydrolysis catalyst, a silane coupling agent, a flame retardant, an antistatic agent, and an antirust agent.

The urethane-curable topcoat paint may further contain a coloring pigment, an extender pigment, and a pigment dispersant. When the resin plate is transparent, the urethane-curable topcoat paint is a clear paint. Is preferred.

Such urethane-curable topcoat paint is
From the viewpoint of pot life, similar to the urethane-curable undercoat paint, the main resin, and optionally other components that do not react with the main resin as a coating liquid, the curing agent and silicate compound, and if necessary, It is preferable that the curing agent and the other components that do not react with the silicate compound are separately stored as a curing agent solution and mixed immediately before use.

The application of the urethane-curable topcoat paint is not particularly limited, and can be usually performed once or twice in the same manner as in the urethane-curable undercoat paint. Here, the term “double coating” means overcoating or whole coating on the whole or a part of the coating film obtained by the immediately preceding coating for the purpose of repairing coating film defects and the like. The coating film thickness is not particularly limited and is, for example, 10 to 10.
It is 100 μm.

After coating, it is appropriately dried and cured to form a stain resistant top coat film. The conditions for drying and curing are not particularly limited, and include, for example, 1 to 5 at room temperature of about 5 to about 40 ° C.
It's about a day.

Thus, the stain resistant resin plate can be manufactured by the first step and the second step.

The stain resistant resin plate obtained by the method for producing a stain resistant resin plate of the present invention exhibits excellent stain resistance.

[0039]

EXAMPLES Production Example 1 Production of Urethane Curable Undercoat Paint Hydroxyl group-containing acrylic resin (solid content 60% by weight, number average molecular weight 3500, solid content hydroxyl value 80, glass transition temperature 5
0 ° C., monomer composition; styrene, methacrylic acid methyl ester, acrylic acid n-butyl ester, methacrylic acid 2-hydroxyethyl ester, methacrylic acid) 10
0.078 parts by weight and 16.78 parts by weight of Coronate HX (manufactured by Nippon Polyurethane Industry Co., Ltd., isocyanurate of hexamethylene diisocyanate, solid content 100% by weight) were mixed with stirring to prepare a urethane curable undercoat paint.
Furthermore, the paint viscosity of Ford Cup No. 1 was reduced with Duflon thinner (a painter of Nippon Paint Co., Ltd., a normally dry organic solvent-based thinner). It was diluted to 4 at 20 seconds / 20 ° C.

Production Example 2 Preparation of Urethane Curing Topcoat Paint
Concrete Zeffle GK500 (manufactured by Daikin Industries, Ltd., hydroxyl group-containing tetrafluoroethylene-olefin copolymer, solid content: 60 wt%)
After 40.0 parts by weight and 20.0 parts by weight of Zeffle GK510 (manufactured by Daikin Industries, Ltd., tetrafluoroolefin copolymer containing a hydroxyl group and a carboxylic acid group, solid content: 60% by weight) are mixed with stirring, further, Coronate HX7.17. Parts by weight and Zeffl GH110 (manufactured by Daikin Industries, Ltd., fluorine atom-containing silicate compound, 100% by weight of active ingredient)
5.1 parts by weight were added, and the mixture was stirred and mixed with a disper to prepare a urethane curable topcoat paint. Furthermore, the paint viscosity of Ford Cup No. It was diluted to 4 at 20 seconds / 20 ° C.

Example 1 An acrylic plate (9 × 30 × 0.7 cm) was coated with the diluted urethane-curable undercoat paint obtained in Production Example 1 at a dry film thickness of 20.
Apply with air spray so that it becomes μm and leave it for 3 hours,
After confirming the dryness to the touch, the diluted urethane curable topcoat paint 1 obtained in Production Example 2 was applied by air spray to a dry film thickness of 25 μm and dried at room temperature for 3 days to prepare a test coated plate.

Comparative Example 1 Except that no urethane-curable undercoat paint was applied,
A test coated plate was prepared in the same manner as in Example 1.

<Evaluation Test> For each test coated plate obtained in Example 1 and Comparative Example 1, the following evaluation test was conducted.
The evaluation results are shown in Table 1.

Adhesiveness The surface of each test coated plate was subjected to a cross-cut test according to JIS K 5400 8.5.4. Further, the same test was carried out on the test coated plate after the stain resistance evaluation described below. Those having a number of cross-cuts of 80% or more are passed.

Contamination resistance After measuring the chromaticity (L value, a value, b value) of the obtained test coated plate with an SM color computer SM-7 (manufactured by Suga Test Instruments Co., Ltd.), JIS Z 2381 6.2. Contamination exposure according to No. 1 was performed, and the color difference (ΔE) after 1 month was measured. Δ
Those with E of 3.0 or less were accepted.

[0046]

[Table 1]

As is clear from Table 1, the stain-resistant resin plate obtained by the method for producing a stain-resistant resin plate of the present invention is excellent in stain resistance and has the adhesion of the stain-resistant coating film. It was found to be good and there was no peeling of the coating film (Example 1). However, it was found that the one which does not use the urethane-curing type undercoating material has low adhesion of the stain resistant coating film and the coating film is easily peeled off (Comparative Example 1).

[0048]

The method for producing a stain resistant resin plate of the present invention comprises:
Since the urethane curing type undercoating is applied to the resin plate to form the undercoating film, the adhesion to the stain resistant topcoating film formed by applying the urethane curing type topcoating product containing the silicate compound It is good.

The stain-resistant resin plate obtained by the method for producing a stain-resistant resin plate of the present invention exhibits excellent durability and stain resistance, and is therefore suitable for use in sound-insulating walls of expressways and booths of toll gates. be able to.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) B32B 27/40 B32B 27/40 (72) Inventor Ryozo Takakawa 19-17 Ikedanaka-cho, Neyagawa-shi, Osaka Japan Into Co., Ltd.F-term (reference) 4D075 AE03 CA13 CA32 CA34 CA47 DA06 DB31 DC02 DC05 EA07 EB16 EB22 EB35 EB38 EB52 EC03 EC54 4F100 AH06C AK01A AK17C AK18 AK25 AK51B JBJB06J01B06BJC06B01B01C31B01C31B01C31B01C31B06C06CAH JN01C

Claims (5)

[Claims] 1. A resin plate is coated with a urethane-curable undercoat paint to form an undercoat paint film, and then a urethane-curable topcoat paint containing a silicate compound is applied to form a stain-resistant overcoat paint film. A method for producing a stain-resistant resin plate, comprising: 2. The method for producing a stain-resistant resin plate according to claim 1, wherein the main resin of the urethane curable topcoat paint is a hydroxyl group-containing fluororesin. 3. The method for producing a stain-resistant resin plate according to claim 1, wherein the silicate compound is a fluorine atom-containing silicate compound. 4. The stain resistance according to any one of claims 1 to 3, wherein the resin plate is a transparent resin plate, and the urethane-curable undercoat paint and the urethane-curable topcoat paint are clear paints. Method for manufacturing resin plate. 5. A stain resistant resin plate obtained by the method for producing a stain resistant resin plate according to any one of claims 1 to 4.