JP2001239607A - Composite molded body made of synthetic resin and method for preparing it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a composite molded body made of a synthetic resin wherein there hardly exists deterioration caused by a metal oxide such as TiO2 in a photocatalyst layer on the surface and peeling of the photocatalyst layer is nothing as the adhesiveness is good and a method for preparing it. SOLUTION: The composite molded body made of the synthetic resin is constituted by integrally laminating an organic adhesive layer 2, an inorganic protective layer 3 and a photocatalyst layer 4 on the surface of a synthetic resin base 1. The synthetic resin base 1 is prevented from being deteriorated caused by a metal oxide in the photocatalyst layer 4 and the photocatalyst layer 4 is prevented from peeling off by remarkably improving adhesiveness by using the organic adhesive layer 2. As the method for preparing it, a transfer film is prepared by laminating the photocatalyst layer, the inorganic protective layer and the organic adhesive layer on a base film and by laminating this transfer film on the synthetic resin base and heating and pressing them, the photocatalyst layer, the inorganic protective layer and an organic adhesive layer are transferred to prepare the composite molded body made of the synthetic resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a synthetic resin composite molded article having a photocatalyst layer on the surface and a method for producing the same.

[0002]

2. Description of the Related Art In recent years, a synthetic resin composite plate has been developed in which a photocatalytic layer is laminated on a surface of a synthetic resin substrate via an inorganic protective adhesive layer.

When this composite plate is exposed to light, the dust attached thereto is decomposed by the photocatalytic action of the photocatalytic layer containing titanium oxide powder as a main component, and the hydrophilic titanium oxide is exposed. It is a convenient thing that has an antifouling action to remove dirt relatively easily by washing with water or natural rainwater, and is also known to have an antibacterial, antifungal and deodorant action. Therefore, a wide range of demand is expected, from architectural materials such as carport shingles and road materials such as highway soundproofing plates to industrial materials such as electronic equipment housings.

In such a composite plate, it is necessary to adhere the photocatalyst layer to the synthetic resin substrate so as not to peel off, and the synthetic resin substrate does not deteriorate due to the adverse effect of titanium oxide contained in the photocatalytic layer. Therefore, the photocatalyst layer is adhered to the surface of the synthetic resin substrate via a silicon-based protective adhesive layer having both adhesiveness and a protective function.

[0005]

However, when the photocatalytic layer is bonded to the synthetic resin substrate via the silicon-based protective adhesive layer as in the above-described composite plate, the silicon-based protective adhesive layer has an adhesive property to the photocatalytic layer. Although good, the difference in thermal expansion and contraction between the photocatalyst layer and the protective adhesive layer and the synthetic resin substrate due to temperature change causes poor adhesion to the synthetic resin substrate, so that the photocatalytic layer is easily peeled from the synthetic resin substrate together with the protective adhesive layer. In order to solve this problem, it has been difficult to improve the adhesion without lowering the protective function of the protective adhesive layer.

In addition, the above-mentioned composite plate has a problem in that the photocatalytic layer is easily peeled off from the synthetic resin substrate due to insufficient adhesion during bending, so that the bending property is not good. Also, it was hard to say that the weather resistance was sufficient.

An object of the present invention is to provide a synthetic resin composite molded article having a photocatalytic layer on its surface and a method for producing the same, which can solve these problems at once.

[0008]

Means for Solving the Problems In order to achieve the above object, a composite molded article made of synthetic resin according to claim 1 of the present invention comprises:
An organic adhesive layer, an inorganic protective layer, and a photocatalyst layer are laminated and integrated on the surface of a synthetic resin substrate.

This composite molded article is provided with an inorganic protective layer having a protective function without interposing a protective adhesive layer having a protective function and adhesiveness between the synthetic resin substrate and the photocatalytic layer as in the conventional product. Since it is interposed separately from the organic adhesive layer having good adhesiveness, the synthetic resin substrate is surely protected by the inorganic protective layer, and the inorganic protective layer adheres tightly to the photocatalytic layer, and the organic Since the organic adhesive layer is strongly adhered to the synthetic resin substrate by the adhesive layer, and the organic adhesive layer can absorb a thermal expansion difference due to a temperature change between the inorganic protective layer and the organic adhesive layer, As a result of substantially eliminating the thermal expansion / contraction difference between the respective layers, the photocatalyst layer is less likely to be separated from the synthetic resin substrate. In addition, this composite molded article has almost no occurrence of peeling of the photocatalyst layer during bending,
In addition, since the synthetic resin substrate is hardly deteriorated in combination with being protected by the inorganic protective layer, the synthetic resin substrate is durable for a long period of time. Thus, the dirt can be relatively easily removed.

[0010] The composite molded article made of synthetic resin according to claim 2 of the present invention is the composite molded article according to claim 1, wherein the synthetic resin substrate is a carbonate-based, ester-based, acrylic-based, olefin-based, or epoxy-based. , Vinyl, or a copolymer thereof, or a substrate formed of a resin of any of these mixtures, wherein the organic adhesive layer is a urethane type,
An acrylic-based, polyvinyl alcohol-based, or vinyl acetate-based adhesive layer, the inorganic protective layer is a silicon-based layer, and the photocatalytic layer is TiO ₂ , ZnO, SnO ₂ ,
It is a layer containing a metal oxide of either SrTiO ₃ or WO ₃ .

Such a composite molded article has strong adhesion between the silicon-based protective layer and the photocatalyst layer, and the silicon-based protective layer can absorb the difference in thermal expansion and contraction of urethane-based and acrylic-based materials. Since the adhesive layer is firmly adhered to the synthetic resin substrate by the system adhesive layer, the peeling resistance of the photocatalyst layer is greatly improved. Moreover, since this silicon protective layer exhibits an excellent protective function, the synthetic resin substrate is made of TiO ₂ contained in the photocatalyst layer.
TiO _{2 and} other metal oxides contained in the photocatalyst layer have a strong photocatalytic action, and can promote the decomposition of dust and the like.

Next, the method for producing a synthetic resin composite molded article according to claim 3 of the present invention is characterized in that a coating for forming a photocatalyst layer is formed on a base film (the surface of the base film may be release-treated). Is applied and dried to form a photocatalytic layer, and then a coating for forming an inorganic protective layer is applied thereon, and dried to form an inorganic protective layer, and an organic adhesive is further applied thereon and dried. Then, a transfer film is prepared by laminating and forming an organic adhesive layer, and the transfer film is superimposed on the surface of the synthetic resin substrate so that the organic adhesive layer is on the synthetic resin substrate side, and heated and pressed. Thus, the organic adhesive layer, the inorganic protective layer, and the photocatalyst layer are transferred to the surface of the synthetic resin substrate.

When such a transfer method is employed, the workability is improved, and in addition, the organic adhesive layer is strongly adhered to the surface of the synthetic resin substrate by heating and pressing at the time of transfer, so that the peeling strength is improved. Can be easily obtained.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a partially enlarged sectional view showing a composite molded article made of synthetic resin according to one embodiment of the present invention.

This composite molded body is obtained by laminating and integrating an organic adhesive layer 2, an inorganic protective layer 3, and a photocatalyst layer 4 on the upper surface of a synthetic resin substrate 1 formed into a plate shape. .

The synthetic resin substrate 1 is made of a thermoplastic resin, for example, a carbonate resin such as polycarbonate, an ester resin such as polyethylene terephthalate, an acrylic resin such as polymethyl methacrylate, an olefin resin such as polypropylene or polyethylene, or a polychlorinated resin. A vinyl resin such as vinyl, or a copolymer or mixture thereof, for example, a mixture of an ethylene-propylene copolymer or a polycarbonate and polyethylene terephthalate, and having a thickness that provides practical strength according to the application. The one having the above-mentioned is used. In some applications, a synthetic resin substrate 1 made of a thermosetting resin such as epoxy or unsaturated polyester is also used. If it is desired to increase the weather resistance, a synthetic resin substrate 1 having a surface layer containing an ultraviolet absorber is also used.

The organic adhesive layer 2 is formed by selecting an adhesive which has good adhesiveness to both the synthetic resin substrate 1 and the inorganic protective layer 3 and can absorb the difference in thermal expansion and contraction. It is necessary to form the layer, and for example, a layer formed using an adhesive such as urethane, acrylic, polyvinyl alcohol, and vinyl acetate is preferable. The thickness of the adhesive layer 2 is preferably formed to be about 0.3 to 10 μm. If the thickness is smaller than 0.3 μm, there is a risk of poor adhesion. Conversely, if the thickness is larger than 10 μm, the adhesion is further improved. Is scarcely seen, so that the adhesive is wasted, and in the adhesive layer 2, intra-layer peeling occurs.

The inorganic protective layer 3 blocks the synthetic resin base 1 and the photocatalyst layer 4 and protects the synthetic resin base 1 so that the synthetic resin base 1 is not deteriorated by a photocatalytic action of TiO ₂ or the like contained in the photocatalyst layer 4. For example, a silicon-based protective layer containing silicone as a main component and uniformly mixed with a binder such as polydimethylsiloxane is preferably used. Such a silicon-based protective layer 3 not only exerts an excellent protective function, but also has good adhesion to the photocatalyst layer 4 and good adhesion to the organic adhesive layer 2, so that the photocatalyst layer 4 has an excellent resistance. The peel strength can be greatly improved.

The inorganic protective layer 3 is preferably formed by laminating to a thickness of about 0.5 to 10 μm. If the thickness is less than 0.5 μm, the protective function of the synthetic resin substrate 1 becomes insufficient, and conversely, the thickness becomes greater than 10 μm. Even if the protection function is hardly further improved, the material is wasted.

The photocatalyst layer 4 is made of TiO ₂ , ZnO, SnO
₂ , a layer in which a metal oxide having a photocatalytic action such as SrTiO ₃ or WO ₃ is uniformly mixed with a binder such as silicone, and when exposed to light, dust or the like adhered to the surface by the photocatalytic action of the metal oxide. Decomposition is promoted. Since the binder of the photocatalyst layer 4 is the same as the main component of the inorganic protective layer 3, such as silicone, the adhesiveness to the inorganic protective layer 3 is good.

The photocatalyst layer 4 is preferably formed by laminating to a thickness of about 0.01 to 10 μm.
When thinner, the promotion of decomposition of dust etc. decreases,
Even if it is formed thicker than m, there is almost no further improvement in promoting the decomposition of dust and the like, so that the material is wasted.

The composite molded article made of a synthetic resin having such a structure is replaced with an inorganic protective layer 3 having a protective function and an organic adhesive having a good adhesive property in place of the conventional protective adhesive layer having both a protective function and an adhesive property. Since the agent layer 2 is formed between the synthetic resin substrate 1 and the photocatalyst layer 4, the peeling resistance can be increased without lowering the protective function.

That is, since the silicon-based protective layer 3 exhibits an excellent protective function, the synthetic resin substrate 1 hardly deteriorates due to the adverse effect of the metal oxide such as TiO ₂ contained in the photocatalytic layer 4. The silicon-based protective layer 3 has excellent adhesion to the photocatalyst layer 4 and excellent adhesion to the organic adhesive layer 2 such as urethane. The organic adhesive layer 2 is firmly bonded to the synthetic resin substrate 1 through the second adhesive layer 2, and causes a difference in thermal expansion and contraction due to a temperature change between the inorganic protective layer 3 and the organic adhesive layer 2. As a result of the absorption, the substantial difference in expansion and contraction between the respective layers can be eliminated. As a result, the peeling resistance is greatly improved, and the peeling of the photocatalyst layer 4 becomes almost equal. Therefore, the composite molded article is less likely to be peeled off during bending, and has good bending workability and the like. In addition, when the composite molded body is exposed to light, the decomposition of attached dust and the like is promoted by the photocatalytic action of the metal oxide such as TiO ₂ contained in the photocatalyst layer 4, and hydrophilic TiO ₂ or the like is formed. Since the metal oxide is exposed, dirt can be relatively easily removed by washing or rainfall.

The above-mentioned synthetic resin composite molded article is preferably produced as follows by the production method of the present invention employing a transfer technique.

First, a coating material for forming a photocatalyst layer is applied on a base film, dried to form a photocatalytic layer having a thickness of about 0.01 to 10 μm, and a coating material for forming an inorganic protective layer is formed thereon. It is applied and dried to form an inorganic protective layer having a thickness of about 0.5 to 10 μm, and an organic adhesive is further applied thereon and dried to form an organic protective layer having a thickness of about 0.3 to 10 μm. A transfer film is produced by laminating an adhesive layer.

As the base film, a polyester film such as PET having a high heat resistance and good releasability is suitably used. And as a photocatalyst layer forming paint,
A coating prepared by mixing the above-mentioned metal oxide such as TiO _{2 with} a binder such as silicone is used. As a coating for forming an inorganic protective layer, a coating prepared by mixing silica with a binder such as polydimethylsiloxane is used. Is used, and the above-mentioned urethane-based, acrylic-based,
Adhesives such as polyvinyl alcohol and vinyl acetate are used. In addition, drying of these paints and adhesives requires 1
It is preferable to heat to about 00 ° C. for about 30 minutes.

When the transfer film is completed, the transfer film is superimposed on the surface of the synthetic resin substrate so that the organic adhesive layer is on the synthetic resin substrate side, and is heated and pressurized. After transferring the inorganic protective layer and the photocatalyst layer to each other, the base film is peeled off to obtain a target synthetic resin composite molded article. The transfer conditions are 100 to 30 which are higher than the softening and melting temperatures of the synthetic resin substrate and the adhesive.
It is preferable to heat to about 0 ° C. and pressure-bond at a pressure of about 10 to 70 kgf / cm ² . When the transfer is performed by applying heat and pressure as described above, the organic adhesive layer 2 strongly adheres to the surface of the synthetic resin substrate 1, so that a composite molded body having a large peeling resistance can be easily manufactured.

An organic adhesive is applied to the surface of the synthetic resin substrate 1 and dried to form an organic adhesive layer 2 on which a coating for forming an inorganic protective layer is applied and dried. The composite molded article may be manufactured by a method in which the system protective layer 3 is formed by lamination, and a coating material for forming a photocatalyst layer is further applied thereon and dried to form the photocatalyst layer 4 by lamination.

FIG. 2 is a partially enlarged cross-sectional view showing a synthetic resin composite molded article according to another embodiment of the present invention.

The composite molded body is a plate-shaped synthetic resin base 1
The organic adhesive layers 2 and 2, the inorganic protective layers 3 and 3, and the photocatalyst layers 4 and 4 are laminated and integrated on both upper and lower surfaces.
Such a composite molded body can be efficiently manufactured by simultaneously transferring the above-described transfer film to both surfaces of the synthetic resin substrate 1. The synthetic resin substrate 1, the organic adhesive layer 2, the inorganic protective layer 3, and the photocatalyst layer 4 are the same as those of the above-described composite molded article in FIG.

In such a composite molded article as well, the synthetic resin base 1 is protected by the inorganic protective layers 3 and 3, so that the synthetic resin base 1 is formed by the metal oxide such as TiO ₂ contained in the photocatalyst layers 4 and 4. There is no deterioration, and the photocatalyst layers 4 and 4 are firmly adhered to both surfaces of the synthetic resin substrate 1 via the inorganic protective layers 3 and 3 and the organic adhesive layer 2, so that there is no fear of peeling. Is equal to nothing.

The synthetic resin composite molded articles according to the above-described embodiments are all examples of plate-shaped composite molded articles. The synthetic resin substrate 1 has a sheet-like, film-like, irregular or other desired shape. It is needless to say that the use of a molded article can be made into a composite molded article having a sheet shape, a film shape, an irregular shape, or any other desired shape.

Next, more specific embodiments of the present invention will be described.

Example 1 A coating for forming a photocatalyst layer prepared by mixing a TiO ₂ powder with a silicone binder was applied to one side of a polyethylene terephthalate (PET) film to a thickness of 0.4 μm. The photocatalyst layer was formed by drying and curing for 30 minutes in the atmosphere described above. On the photocatalyst layer, a coating for forming an inorganic protective layer prepared by mixing silica with a binder of polydimethylsiloxane was applied to a thickness of 1.0 μm.
Was dried and cured for 30 minutes in the atmosphere described above to form an inorganic protective layer. Further, a urethane-based adhesive (Nipporan 3016 manufactured by Nippon Polyurethane Co., Ltd.) is applied to a thickness of 2 μm on this inorganic protective layer, and dried in an atmosphere at 100 ° C. for 30 minutes to form an organic adhesive. A transfer film was produced by laminating the agent layers.

Next, the above-mentioned transfer film was laminated on the upper surface of a polycarbonate plate having a thickness of 2 mm such that the organic adhesive layer was on the polycarbonate plate side, and the temperature was 270.
After thermocompression bonding under the conditions of ° C and a pressure of 20 kgf / cm ² , the organic adhesive layer, inorganic protective layer, and photocatalyst layer of the transfer film were simultaneously transferred to the surface of the polycarbonate plate, and then the PET film was peeled off. Was produced.

Then, bending workability and adhesiveness of the obtained composite molded body were examined. The results are shown in Table 1 below.

The bending workability shown in Table 1 was evaluated by cutting a sample obtained by cutting the obtained synthetic resin composite molded article into 200 × 50 mm, heating it at 140 ° C. for 10 minutes, and bending it into an L-shape. It is visually determined whether or not a crack is formed in the bent portion. The case where a crack is formed is indicated by x, and the case where no crack is formed is indicated by ○. The adhesion is JISK
This was evaluated by a 5400 grid test.

Example 2 The urethane-based adhesive used in Example 1 was applied to the surface of the polycarbonate plate used in Example 1 to a thickness of 2 μm, and dried in an atmosphere at 100 ° C. for 1 hour. To form an organic adhesive layer. And
On the organic adhesive layer, the inorganic protective layer forming paint used in Example 1 was applied to a thickness of 1.0 μm,
, And dried and cured for 1 hour in the atmosphere described above to form an inorganic protective layer. Further, the photocatalyst layer forming paint used in Example 1 was applied to a thickness of 0.4 μm on this inorganic protective layer, and dried and cured in an atmosphere at 100 ° C. for 1 hour to form a photocatalyst layer. By laminating, a composite molded article made of a plate-like synthetic resin was manufactured.

The obtained composite molded body was examined for bending workability and adhesion in the same manner as in Example 1, and the results are shown in Table 1 below.

Example 3 Instead of urethane-based adhesive,
Acrylic adhesive (HM650 manufactured by Cemedine Co., Ltd.)
In the same manner as in Example 2 except that the organic adhesive layer was formed by lamination, a plate-shaped synthetic resin composite body was manufactured.

Then, bending workability and adhesion were examined for the composite molded body in the same manner as in Example 1, and the results are shown in Table 1 below.

[Comparative Example 1] The coating for forming the inorganic protective layer used in Example 1 was applied to the surface of the polycarbonate plate used in Example 1 to a thickness of 1.0 µm, and the coating was performed in an atmosphere at 100 ° C. After drying and curing for 1 hour, an inorganic protective layer was laminated. Then, the photocatalyst layer forming paint used in Example 1 was applied to a thickness of 0.4 μm on the inorganic protective layer,
By drying and curing in an atmosphere at 100 ° C. for 1 hour to form a laminated photocatalytic layer, a composite molded article without an organic adhesive layer was produced.

Table 1 below shows the results obtained by examining the bending workability and the adhesion of the composite molded body in the same manner as in Example 1.

[0045]

[Table 1]

As shown in Table 1, the composite molded articles of Examples 1 to 3 in which the organic adhesive layer and the inorganic protective layer were interposed between the polycarbonate plate and the photocatalyst layer had high peeling strength. Therefore, cracks do not enter during bending,
The composite molded articles of Examples 1 and 2 in which the urethane-based adhesive layer was formed had a satisfactory evaluation of a perfect score (10 points). The evaluation of 8 points was also obtained with the composite molded article of Example 3 in which was formed.

On the other hand, the composite molded article of Comparative Example 1 lacking the organic adhesive layer had insufficient peeling resistance and easily peeled off the photocatalyst layer. Was as low as 4 points.

From the above, when the photocatalyst layer is bonded to the synthetic resin substrate via the organic adhesive layer and the inorganic protective layer, the photocatalyst layer is strongly adhered, so that the photocatalyst layer is hardly peeled off. It can be seen that the characteristics are significantly improved.

[0049]

As is clear from the above description, in the composite molded article made of synthetic resin of the present invention, since the synthetic resin base is protected by the inorganic protective layer, the TiO 2 contained in the photocatalyst layer is protected.
_The synthetic resin substrate is hardly degraded by metal oxides such as ₂ and has excellent durability. Focusing on the improvement of each functional performance by dividing the functional purpose into an inorganic protective layer and an organic adhesive layer The adhesive strength (peeling resistance) is remarkably improved by the organic adhesive layer and the difference in thermal expansion and contraction can be absorbed. This has the effect of preventing cracks.

The production method of the present invention using the transfer method has good workability, and the organic adhesive layer is strongly adhered to the synthetic resin substrate by heating and pressing at the time of transfer, so that the composite material having a large peeling strength is obtained. A molded article can be easily manufactured.

[Brief description of the drawings]

FIG. 1 is a partially enlarged cross-sectional view illustrating a composite molded body made of a synthetic resin according to an embodiment of the present invention.

FIG. 2 is a partially enlarged cross-sectional view showing a synthetic resin composite molded body according to another embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 1 synthetic resin base 2 organic adhesive layer 3 inorganic protective layer 4 photocatalyst layer

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Takaki Suzuki 2-3-13 Azuchicho, Chuo-ku, Osaka City Inside Takiron Co., Ltd. (72) Inventor Takayuki Sano 2-33-1 Azuchicho, Chuo-ku, Osaka City Inside Takiron Co., Ltd. (72) Inventor Yasushi Toyama 2-3-13 Azuchi-cho, Chuo-ku, Osaka-shi F-term inside Takiron Co., Ltd. AK21B AK21G AK25A AK25B AK25G AK41A AK45A AK51B AK51G AK53A AL01A AL05A BA04 BA07 BA10A BA10D CA30D CB00B EC042 EG002 EH112 EH462 EJ172 EJ422 GB07 GB48 GB90 JK06 JL00 JL11 4G069 AA03 AA08 BA04A BA04B BA48A BB04A BC12A BC22A BC35A BC50A BC60A CD10 DA05 EA01X EB15Y ED02 ED04 FA03 FB23

Claims (3)

[Claims] 1. A synthetic resin composite molded article comprising an organic adhesive layer, an inorganic protective layer and a photocatalytic layer laminated and integrated on the surface of a synthetic resin substrate. 2. The synthetic resin substrate is a substrate formed of a resin of a carbonate type, an ester type, an acrylic type, an olefin type, an epoxy type, a vinyl type, a copolymer thereof, or a mixture thereof. Yes, the organic adhesive layer is a urethane-based, acrylic, polyvinyl alcohol-based, or vinyl acetate-based adhesive layer, the inorganic protective layer is a silicon-based layer, the photocatalytic layer is TiO ₂ , Zn
O, SnO _2, SrTiO _3, a layer containing any of the metal oxides WO _3, a synthetic resin composite molded article according to claim 1. 3. A photocatalytic layer-forming paint is applied on the base film and dried to form a photocatalyst layer. The inorganic protective layer-forming paint is applied and dried to form an inorganic protective layer. A transfer film is formed by forming a laminate, further applying an organic adhesive thereon, and drying to form an organic adhesive layer. The transfer film is formed on the synthetic resin substrate side. A synthetic resin composite, characterized in that an organic adhesive layer, an inorganic protective layer and a photocatalyst layer are transferred to the surface of the synthetic resin substrate by applying heat and pressure on the surface of the synthetic resin substrate so that A method for producing a molded article.