JP2013132787A - Anti-static laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an anti-static laminate which has all of excellent weather resistance, chemical resistance, and resistance to IPA wiping by incorporating a specific binder resin in an anti-static layer.SOLUTION: The anti-static laminate has: a resin base material 1; and the anti-static layer 2 formed on at least one surface of the resin base material 1, wherein the anti-static layer 2 is made with an electroconductive polymer and the binder resin as a main component. The binder resin is a mixed resin obtained by mixing a polyester resin and a polyurethane resin, and the surface resistivity of the anti-static layer 2 is less than 10Ω/sq. The anti-static laminate is made to exhibit excellent weather resistance by the polyester resin being one component of the binder resin of the anti-static layer, excellent chemical resistance by the polyurethane resin being the other component of the binder resin, and excellent resistance to IPA wiping by these resins.

Description

  The present invention relates to an antistatic laminate that releases static electricity and prevents adhesion of dust and the like, and more particularly, to an antistatic laminate that has both good weather resistance, chemical resistance, and alcohol wiping resistance.

  Conventionally, for applications that dislike dust, such as partitions in clean rooms, an antistatic resin plate that releases static electricity and prevents the adhesion of dust has been used. This antistatic resin plate is a laminate in which an antistatic layer is provided on at least one surface of a resin substrate directly or via an adhesive layer. For example, an antistatic layer containing a conductive polymer and a binder resin is provided. The provided ones are used.

  As one of antistatic laminates in which an antistatic layer including such a conductive polymer and a binder resin is provided on at least one surface of a resin base material, a resin laminate described in Patent Document 1 below is known. ing. This resin laminate includes a π-electron conjugated conductive polymer and a resin selected from a polyester resin, a polyurethane resin, a polyester urethane resin, an acrylic resin, and a melamine resin on at least one surface of the resin molded body. It has an antistatic layer containing, and further has a cured coating layer formed by curing a curable resin on the antistatic layer, and is excellent in antistatic properties, scratch resistance, and transparency. There is a description.

International Publication No. 08/035660

However, as the π-electron conjugated conductive polymer, the PEDOT / PSS polymer complex [complex of poly (3,4-ethylenedioxythiophene) and polystyrene sulfonic acid] described in Patent Document 1 is used, The antistatic laminate obtained by laminating the antistatic layer mainly composed of PEDOT / PSS polymer complex and, for example, polyester resin on one side of the resin base material has good weather resistance as can be seen from the test data described later. to have, but on the other hand, is inferior in chemical resistance, added dropwise and the like 60% sulfuric acid, antistatic layer is deteriorated in a short period of time, antistatic surface resistivity is increased to more than 10 ⁴ times before immersion There was a problem that the property was impaired.

Further, the antistatic laminate obtained by laminating and forming the antistatic layer mainly composed of the PEDOT / PSS polymer complex and, for example, polyurethane resin on one side of the resin base material has a good chemical resistance. However, since the polyurethane resin contained in the antistatic layer is inferior in weather resistance to the polyester resin, the antistatic layer deteriorates in a relatively short time when an exposure test is performed using, for example, a xenon weatherometer. As a result, the surface resistivity of the antistatic layer increased to 10 ¹⁴ Ω / □ or more, and the antistatic property was not exhibited at all.

  In addition, the antistatic resin plate (laminate) used in clean room partitions has a large surface resistivity even after repeated wiping and cleaning with a wiping cloth containing alcohols such as isopropyl alcohol (IPA). Alcohol wiping resistance (hereinafter referred to as IPA wiping resistance) that can suppress the rise is required, but conventional antistatic resin plates (laminates) are also insufficient in terms of IPA wiping resistance. there were.

  The present invention has been made under the above circumstances, and the problem to be solved is an antistatic laminate in which an antistatic layer mainly composed of a conductive polymer and a binder resin is provided on at least one side of a resin base material. Then, it is providing the antistatic laminated body improved so that it might have favorable weather resistance, chemical resistance, and IPA wiping-off property by employ | adopting specific binder resin.

In order to solve the above problems, an antistatic laminate according to the present invention is an antistatic laminate having a resin base material and an antistatic layer formed on at least one side of the resin base material, and the antistatic layer Is a layer mainly composed of a conductive polymer and a binder resin, the binder resin is a mixed resin of a polyester resin and a polyurethane resin, and the surface resistivity of the antistatic layer is less than 10 ⁹ Ω / □ It is what.

  In the antistatic laminate of the present invention, the mixing ratio of the polyester resin and the polyurethane resin is preferably 1: 9 to 8: 2 by mass ratio. The antistatic layer preferably contains an ultraviolet absorber, and the ultraviolet absorber is preferably zinc oxide and / or cerium oxide.

As in the antistatic laminate of the present invention, when the binder resin contained in the antistatic layer is a mixed resin of a polyester resin and a polyurethane resin, the polyester resin has good weather resistance as can be seen from the test data described later. And good chemical resistance is exhibited by the polyurethane resin. And the chemical resistance which is a weak point of a polyester resin is supplemented with a polyurethane resin, and the weather resistance which is a weak point of a polyurethane resin is supplemented with a polyester resin. For this reason, even if a chemical solution is dropped or an exposure test is performed with a xenon weatherometer, the surface resistivity of the antistatic layer is not increased, and the total light transmittance and haze are not increased. Further, when the binder resin contained in the antistatic layer is a mixed resin of a polyester resin and a polyurethane resin, as can be seen from the test data described later, the IPA wiping resistance is good, and the wiping cloth containing IPA is used. Even if wiping and cleaning are repeated, a significant increase in surface resistivity can be suppressed. Needless to say, when the surface resistivity of the antistatic layer is less than 10 ⁹ Ω / □ as in the antistatic laminate of the present invention, good antistatic properties are exhibited and adhesion of dust and the like can be prevented. .

  As described above, the mixing ratio of the polyester resin and the polyurethane resin is preferably 1: 9 to 8: 2 in terms of mass ratio. If the mixing ratio is within the range, good weather resistance, chemical resistance, resistance An antistatic laminate having both IPA wiping properties can be obtained. When the polyester resin is more than 8 by mass and the polyurethane resin is less than 2 by mass, the antistatic layer has insufficient chemical resistance, while the polyester resin is less than 1 by mass and the polyurethane resin is less by mass. If it exceeds 9, the adhesion between the base resin and the antistatic layer is lowered in addition to the insufficient weather resistance. Inconveniences such as difficulty occur.

  When the antistatic layer contains an ultraviolet absorber, the weather resistance is further improved. In particular, when the ultraviolet absorber is zinc oxide and / or cerium oxide, the improvement in weather resistance becomes remarkable, and xenon The increase in haze and the increase in surface resistivity are drastically reduced when an exposure test is conducted with a weatherometer.

It is sectional drawing of the antistatic laminated body which concerns on one Embodiment of this invention. It is a graph which shows the light absorbency of the polyester modified polyurethane resin coating film in a 200-500 nm wavelength range, and a vinyl chloride-vinyl acetate copolymer resin coating film.

  The antistatic laminate shown in FIG. 1 is a three-layer laminate having a resin base material 1 and an antistatic layer 2 formed on one side of the resin base material 1 with an adhesive layer 3 interposed therebetween. The adhesive layer 3 and the antistatic layer 2 may be formed on both surfaces of the resin substrate 1, and the adhesive layer 3 may be omitted as will be described later.

  The resin substrate 1 is made of a known thermoplastic resin or a known curable resin that is cured by heat, ultraviolet light, electron beam, radiation, or the like. Examples of the thermoplastic resin include polyethylene, polypropylene, and cyclic polyolefin. Such as olefin resin, polyvinyl chloride resin, vinyl resin such as polymethyl methacrylate, polystyrene, cellulose resin such as nitrocellulose, triacetyl cellulose, ester such as polycarbonate, polyethylene terephthalate, polydimethylcyclohexane terephthalate, aromatic polyester Resin, ABS resin, copolymer resins and mixed resins of these resins are used, and as the curable resin, for example, a thermosetting or ultraviolet curable resin such as an epoxy resin, a polyimide resin, or an acrylic resin is used. Be done

The shape of the resin base material 1 may be a plate shape, a sheet shape, a film shape, or an irregular shape according to the use of the antistatic laminate, and may be colorless, transparent or translucent, colored transparent or translucent. However, it may be colored and opaque. For example, in the case of an antistatic laminate used for applications such as the above-mentioned clean room partition, a transparent polyvinyl chloride or polycarbonate plate is suitable.
The resin base material 1 is appropriately mixed with a plasticizer, a stabilizer, an anti-oxidant and other additives.

  The antistatic layer 2 is a layer mainly composed of a conductive polymer and a binder resin. As the conductive polymer, a complex of a π-conjugated conductive polymer and a polymer serving as an acceptor as a dopant is suitable. For example, water-dispersible π-conjugated conductive polymers such as polythiophene, polyalkylthiophene, polyalkyldioxythiophene, and polysulfonic acid (polystyrenesulfonic acid, polyvinylsulfonic acid, etc.), polycarboxylic acid (polyacrylic acid, polymethacrylic acid, etc.) A polymer complex with an acceptor such as an acid or polymaleic acid is preferably used. Among these, a PEDOT / PSS polymer complex that is easily available, that is, a complex of a polymer of 3,4-ethylenedioxythiophene and a polymer of styrenesulfonic acid is particularly preferably used.

The content of the conductive polymer is not limited, but in order to give good antistatic properties with a surface resistivity of 10 ⁴ Ω / □ or more and less than 10 ⁹ Ω / □, the content of the conductive polymer (solid content ) Is adjusted to about 1 to 60% by mass, preferably about 1 to 30% by mass of the content (solid content) of the binder resin. In particular, it is more preferable that the content (solid matter) of the conductive polymer is 1 to 25% by mass, since white turbidity does not occur in the antistatic layer after stamping.

  As the binder resin of the antistatic layer 2, it is necessary to use a mixed resin of a polyester resin and a polyurethane resin. When the antistatic layer 2 is formed using such a mixed resin as a binder resin, good weather resistance, chemical resistance, An antistatic laminate having both IPA wiping properties can be obtained.

  Any polyester resin can be used as the polyester resin, which is one component of the mixed resin. Among them, a water-dispersible polyester resin is used corresponding to the water-dispersible conductive polymer contained in the antistatic layer 2. In particular, a water-dispersible acrylic-modified polyester resin is preferably used. Polyester resins are inferior in chemical resistance, but those modified with acrylic have the advantage that the antistatic layer 2 having good chemical resistance can be formed because the chemical resistance is improved, and the antistatic layer 2 may be whitened. Absent. The polyester resin preferably has a glass transition point of 0 ° C. or higher. When such a polyester resin is used, there is an advantage that blocking of the antistatic layer 2 can be prevented.

  The polyurethane resin, which is the other component of the mixed resin, can be any polyurethane resin. Among them, the water-dispersible polyurethane resin having a hydrophilic group such as a carboxyl group corresponding to the water-dispersible conductive polymer. In particular, a water dispersible polyurethane resin having a glass transition point of 0 ° C. or higher, preferably in the range of 70 to 120 ° C. is preferably used. A polyurethane resin having a glass transition point lower than 0 ° C. is gelled when mixed with the PEDOT / PSS polymer complex, which is a conductive polymer, and the formation of the antistatic layer 2 becomes difficult. A water dispersible polyurethane resin in the range of 70 to 120 ° C. is preferable.

  When a mixed resin of the above polyester resin and polyurethane resin is used as the binder resin of the antistatic layer 2, weather resistance is exhibited by the polyester resin, and good adhesion of the antistatic layer 2 is obtained. Good chemical resistance is exhibited. And the chemical resistance which is a weak point of a polyester resin is supplemented with a polyurethane resin, and the weather resistance which is a weak point of a polyurethane resin is supplemented with a polyester resin. Therefore, even when a chemical solution is dropped on the antistatic laminate or exposed with a xenon weatherometer in the chemical resistance test or weather resistance test described later, the surface resistivity of the antistatic layer 2 does not increase so much. There is little decrease in transmittance and increase in haze. Moreover, the anti-IPA wiping resistance of the antistatic layer 2 is also good, and a significant increase in surface resistivity can be suppressed even if wiping and washing are repeated with a wiping cloth containing IPA.

  The mixing ratio of the polyester resin and the polyurethane resin is preferably 1: 9 to 8: 2 in terms of the mass ratio of the solid content, and the mixture resin of the polyester resin and the polyurethane resin having such a mixing ratio is used as the antistatic layer 2. When used as a binder resin, it is possible to form the antistatic layer 2 having both good weather resistance, chemical resistance, and IPA wiping resistance. When the polyester resin exceeds 8 by mass and the polyurethane resin is less than 2 by mass, the antistatic layer 2 has insufficient chemical resistance, while the polyester resin is less than 1 by mass and the polyurethane resin is mass. When the ratio exceeds 9, the weather resistance is insufficient and the adhesion (adhesion) of the antistatic layer 2 to the resin substrate 1 is also poor. Lamination formation becomes difficult, and the omission of the adhesive layer 3 becomes impossible. Further, it is desirable to increase the chemical resistance of the antistatic layer 2 by increasing the amount of the polyurethane resin having good chemical resistance than the amount of the polyester resin. In this case, the antistatic layer 2 contains an ultraviolet absorber. It is desirable to increase weather resistance.

  As described above, it is desirable that the antistatic layer 2 contains an ultraviolet absorber in order to improve weather resistance. Examples of the ultraviolet absorber include hydroxyphenyltriazine, hindered amine, benzotriazole, and benzophenone. Known organic ultraviolet absorbers and inorganic ultraviolet absorbers made of metal oxides such as zinc oxide and cerium oxide are used. In particular, the latter metal oxides such as zinc oxide and cerium oxide are preferably used because they have a greater effect of improving the weather resistance of the antistatic layer 2 than the former organic ultraviolet absorbers. These metal oxides have an average particle size of about 5 to 80 nm, preferably about 10 to 40 nm.

  Although content of a ultraviolet absorber is not specifically limited, In order to provide favorable weather resistance to the antistatic layer 2, in the case of an organic type ultraviolet absorber, the content is content of binder resin (the said mixed resin). (Solid content) is preferably adjusted to about 0.1 to 40% by mass, preferably about 1 to 16% by mass, and also in the case of an inorganic ultraviolet absorber (the metal oxide), the content is adjusted. The content (solid content) of the binder resin (the mixed resin) is adjusted to about 0.1 to 40% by mass, preferably about 1 to 16% by mass.

  The antistatic layer 2 may contain a compound having a carbodiimide group. As the compound having a carbodiimide group, dicyclohexyl obtained by adding polyethylene oxide monomethyl ether, propylene glycol monomethyl ether, N, N-diethylisopropanolamine, propylene glycol monophenyl ether, tripropylene glycol monomethyl ether, etc. to isocyanate-terminated dicyclohexylmethane carbodiimide, respectively. Examples include methane carbodiimide derivative compounds and tetramethylxylylene carbodiimide derivatives. The content of the compound having a carbodiimide group is desirably 2.7 to 25% by mass with respect to the content of the binder resin (the mixed resin) of the antistatic layer 2.

  When the antistatic layer 2 contains a compound having a carbodiimide group, the carbodiimide group reacts with a hydrophilic carboxyl group or the like in the polymer molecule of the binder resin (the mixed resin) to form a crosslinked structure. When the wiping and washing are repeated, it becomes difficult to inhibit energization of the conductive polymer due to swelling of the binder resin, so that the anti-IPA wiping resistance of the antistatic layer 2 is improved, and whitening of the antistatic layer 2 due to IPA wiping is also prevented. become able to.

  The thickness of the antistatic layer 2 is not particularly limited, but is appropriately set to about 10 nm to 700 nm. The antistatic layer 2 thinner than 10 nm is not easy to form, and the antistatic layer 2 thicker than 700 nm is wasteful of materials and uneconomical.

  The adhesive layer 3 is necessary when the antistatic layer 2 having poor adhesion (adhesiveness) to the resin base material 1 is formed on at least one surface of the resin base material 1 by thermal transfer. When the antistatic layer 2 containing a binder resin having a good adhesive property (for example, the mixed resin having a large amount of the polyester resin having a good adhesive property) is directly transferred to at least one surface of the resin substrate 1, or directly applied. Can be omitted.

  Examples of the resin forming the adhesive layer 3 include a heat-sensitive adhesive resin having alcohol resistance that is not easily altered or deteriorated by IPA, such as an olefin resin, a vinyl chloride resin, a vinyl chloride-vinyl acetate copolymer resin, a polyester resin, Urethane-modified copolymer polyester resins and the like are suitable, and among them, vinyl chloride-vinyl acetate copolymer resins and urethane-modified copolymer polyester resins are preferably used from the viewpoint of IPA wiping resistance and adhesive strength. An acrylic resin or the like is also used. From the viewpoint of weather resistance, an adhesive that absorbs less in the ultraviolet region (200 to 400 nm) is preferable, and vinyl chloride-vinyl acetate copolymer resin is particularly preferable.

  The thickness of the adhesive layer 3 is not particularly limited, but is preferably about the same as or greater than that of the antistatic layer 2, and specifically, is set to about 100 nm to 3 μm.

  Said antistatic laminated body is efficiently manufactured, for example with the following manufacturing method.

  In the first production method, first, on one side of a release film, an antistatic layer mainly composed of the conductive polymer and the binder resin (a mixed resin of the polyester resin and the polyurethane resin), or the ultraviolet absorption. Producing a transfer film having a three-layer laminated structure in which an antistatic layer further containing an agent or a compound having a carbodiimide group and an adhesive layer made of the alcohol-resistant resin are laminated in this order; The transfer film is laminated on the surface of the resin substrate such that the adhesive layer is on the resin substrate side, and heated and pressurized to a temperature higher than the melting point of the resin of the adhesive layer, and the transfer film adhesive layer and antistatic layer Is a method for producing an antistatic laminate by thermally transferring at least one surface of a resin substrate. The transfer pressure and transfer time are not particularly limited. For example, it is appropriate to set the transfer pressure to about 9 to 30 MPa and set the transfer time to about 0.1 to 1800 sec.

When the antistatic laminate is manufactured by thermal transfer as described above, the resin having the alcohol resistance of the adhesive layer 3 easily penetrates and mixes into the antistatic layer 2 by the transfer pressure, and the surface of the antistatic layer 2 is IPA. When the wiping is performed, the swelling of the binder resin of the antistatic layer 2 is suppressed by the mixed alcohol-resistant resin and it is difficult for the conductive polymer to be inhibited from being energized. It can be further improved and good antistatic properties of less than 10 ⁹ Ω / □ can be maintained.

  In the second production method, on one side of the release film, the antistatic layer mainly composed of the binder resin (the mixed resin having a large amount of polyester resin) having good adhesiveness with the conductive polymer, or the ultraviolet ray A transfer film having a two-layer laminated structure in which an antistatic layer further containing an absorbent and the compound having the carbodiimide group is laminated is prepared, and this transfer film is resin so that the antistatic layer is on the resin substrate side. This is a method for producing an antistatic laminate without the adhesive layer 3 by superimposing, heating and pressing on the surface of the base material, and directly transferring the antistatic layer of the transfer film to at least one surface of the resin base material.

  The third production method is the formation of an antistatic layer further comprising the composition for forming an antistatic layer mainly composed of the conductive polymer and the binder resin, or the compound having the ultraviolet absorber or the carbodiimide group. The antistatic laminated body without the adhesive layer 3 is manufactured by preparing a composition for use and directly applying and drying the composition on at least one surface of a resin substrate to form an antistatic layer.

  Since the antistatic laminate obtained by each of the above production methods has the antistatic layer 2 mainly composed of a conductive polymer and a mixed resin (binder resin) of a polyester resin and a polyurethane resin, the polyester resin Good weather resistance is exhibited by the polyurethane resin, and good chemical resistance is exhibited by the polyurethane resin. And the chemical resistance which is a weak point of a polyester resin is supplemented with a polyurethane resin, and the weather resistance which is a weak point of a polyurethane resin is supplemented with a polyester resin. For this reason, even if a chemical solution is dropped or an exposure test is performed with a xenon weatherometer, the surface resistivity of the antistatic layer 2 is not increased, and the total light transmittance is decreased and the haze is decreased. In particular, the antistatic laminate in which the antistatic layer 2 contains an ultraviolet absorber has excellent weather resistance. Further, the antistatic layer 2 containing a mixed resin of a polyester resin and a polyurethane resin as a binder resin also has good IPA wiping resistance, and in particular, the antistatic layer 2 contains a compound having a carbodiimide group. In addition, a resin in which the alcohol-resistant resin of the adhesive layer 3 has permeated and mixed into the antistatic layer 2 has excellent IPA wiping resistance.

  Next, a chemical resistance test, a weather resistance test, and an IPA wiping resistance test performed on the antistatic laminate of the present invention will be described.

[Chemical resistance test 1]
The water-dispersible acrylic-modified polyester resin [A515GE manufactured by Takamatsu Yushi Co., Ltd.] and the water-dispersible polyurethane resin [Flex 170 manufactured by Daiichi Kogyo Seiyaku Co., Ltd.] 4 mass ratios) are used as binder resins, and 6 mass% of PEDOT / PSS polymer complex is blended as a conductive polymer in each binder resin to prepare four types of antistatic layer forming compositions. did. The antistatic laminate is formed by applying these antistatic layer-forming compositions on one side of a resin base material (polycarbonate plate having a thickness of 3 mm) and drying to form an antistatic layer (approximately 300 nm in thickness). Samples 1 to 4 were prepared.
2 ml each of ammonia, 60% sulfuric acid, and 60% nitric acid was dropped on each of these samples 1 to 4, and the surface resistivity before dropping and the surface resistivity after standing for 24 hours after dropping were made by Dia Instruments Co., Ltd. Measured with Hiresta UP to check the quality of chemical resistance. The results are shown in Table 1 below.
For comparison, Comparative Sample 1 in which the binder resin was changed to only the acrylic-modified polyester resin and Comparative Sample 2 in which the binder resin was changed to only the polyurethane resin were prepared, and the quality of the chemical resistance was examined in the same manner as described above. The results are also shown in Table 1 below.

From Table 1, Comparative Sample 1 using a polyester resin alone as the binder resin of the antistatic layer shows that the surface resistivity of the antistatic layer after dropping 60% sulfuric acid and 60% nitric acid is the surface resistivity before dropping. In particular, the surface resistivity after dropping 60% sulfuric acid is 10 ¹⁰ Ω / □ or more, and the antistatic property is lost. From this, it can be seen that Comparative Sample 1 is inferior in chemical resistance.
In contrast, samples 1 to 4 of the antistatic laminate of the present invention using a mixed resin of a polyester resin and a polyurethane resin as a binder resin for the antistatic layer, and a polyurethane resin alone as the binder resin for the antistatic layer In the comparative sample 2 used, the surface resistivity of the antistatic layer after dropping ammonia, 60% sulfuric acid, and 60% nitric acid hardly increased as compared with the surface resistivity before dropping, and 10 ⁹ Ω even after dropping. It can be seen that the surface resistivity is less than / □ and has good chemical resistance.

[Chemical resistance test 2]
2 ml of ammonia, 60% sulfuric acid, and 60% nitric acid were dropped on samples 1, 2, 4 and comparative samples 1, 2 of the antistatic laminate prepared in the above chemical resistance test 1, respectively, and manufactured by Suga Test Instruments Co., Ltd. Using a direct reading haze computer NDH5000, the total light transmittance and haze of samples 1, 2, and 4 after being allowed to stand for 24 hours after dropping, and the total amount after being allowed to stand for 24 hours before and after dropping of comparative samples 1 and 2 The light transmittance and haze were measured to check the chemical resistance. The results are shown in Table 2 below.

From Table 2, in Comparative Samples 1 and 2, the total light transmittance after dropping 60% sulfuric acid and 60% nitric acid is slightly increased or decreased compared to the total light transmittance before dropping. It can be seen that Comparative Sample 1 using a polyester resin alone as the binder resin for the electric layer has a significantly increased haze after dropping compared with that before dropping, and is inferior in chemical resistance. On the other hand, the comparative sample 2 using a polyurethane resin alone as the binder resin of the antistatic layer is such that the haze after dropping is slightly increased as compared to before dropping, and is 3.5 to 4.3%. The range is maintained, and it can be seen that it has good chemical resistance.
The samples 1, 2, and 4 of the antistatic laminate of the present invention using a mixed resin of a polyester resin and a polyurethane resin as the binder resin of the antistatic layer are all made of ammonia, 60% sulfuric acid, and 60% nitric acid. The total light transmittance after the dripping is not inferior to that after the dropping of the comparative sample 2, and the haze after dropping is equal to or slightly higher than that after the dropping of the comparative sample 2 and is not much different from the comparative sample 2. It can be seen that it has excellent chemical resistance.

[Weather resistance test 1]
The water-dispersible acrylic-modified polyester resin [A515GE manufactured by Takamatsu Yushi Co., Ltd.] and the water-dispersible polyurethane resin [Flex 170 manufactured by Daiichi Kogyo Seiyaku Co., Ltd.] The mixture resin mixed at a mass ratio of each minute was used as a binder resin, and 6% by mass of PEDOT / PSS polymer complex as a conductive polymer was blended with each binder resin to prepare an antistatic layer forming composition.
On one side of the PET film, the antistatic layer forming composition having a mixing ratio of acrylic modified polyester resin and polyurethane resin of 8: 2, 6: 4, 4: 6, 2: 8 is applied and dried. An antistatic layer having a thickness of 300 nm was formed, and an acrylic resin liquid was applied thereon and dried to form an adhesive layer having a thickness of 1 μm. Thus, four types of transfer films were obtained. The antistatic laminate of the present invention in which an adhesive layer is interposed between the resin base material and the antistatic layer by thermally transferring each transfer film to one surface of the resin base material (polycarbonate plate having a thickness of 3 mm). Samples 5 to 8 were prepared.
Also, the antistatic layer-forming composition having a mixing ratio of acrylic modified polyester resin and polyurethane resin of 2: 8 and 0:10 was applied to one side of the PET film and dried to give a 300 nm thick antistatic material. Two layers of transfer films were obtained by forming a layer, applying a urethane-modified polyester resin solution instead of the acrylic resin solution, and drying to form an adhesive layer having a thickness of 1 μm. Then, each of the transfer films is thermally transferred to one surface of the resin base material, whereby the antistatic laminate sample 9 and the comparative sample 4 of the present invention in which an adhesive layer is interposed between the resin base material and the antistatic layer are obtained. Produced.
The above samples 5 to 9 and comparative sample 3 were exposed to a xenon weatherometer [X75] manufactured by Suga Test Instruments Co., Ltd. for 100 hours, 300 hours, and 500 hours, respectively, and subjected to a weather resistance test. The transmittance and haze were measured by the direct reading haze computer NDH5000, and the weather resistance was checked. For Comparative Sample 3, total light transmittance and haze before exposure were also measured. These results are shown in Table 3 below.

As can be seen by comparing each sample in Table 3, the weather resistance is improved as the antistatic layer is formed using a binder resin having a large blending ratio of the polyester resin, and the total light transmittance after exposure is reduced. It can be seen that the increase in haze tends to decrease. In particular, the comparative sample 4 in which the antistatic layer was formed using only the polyurethane resin as the binder resin increased the haze to 10.8% (approximately 5.7 times before the exposure) even after being exposed for 100 hours. It can be seen that the weather resistance is inferior to the mixed sample.
Samples 5 to 8 having an adhesive layer formed of an acrylic resin have higher total light transmittance after exposure for 300 hours and after exposure for 500 hours, compared with Sample 9 having an adhesive layer formed of urethane-modified polyester resin. Therefore, it can be seen that forming an adhesive layer with an acrylic resin is effective in improving weather resistance.

[Weather resistance test 2]
The sample 10 in which the binder resin of the antistatic layer was changed to a mixed resin having a mixing ratio of polyester resin and polyurethane resin of 1: 9, the adhesive layer was omitted, and the antistatic layer was directly formed on the resin substrate, It was produced by a manufacturing method by coating. Moreover, the binder resin of the antistatic layer was changed to only the polyester resin, and the comparative sample 3 in which the antistatic layer was formed on the resin base material through the adhesive layer of the acrylic resin was produced by the manufacturing method using the transfer described above.
Samples 5 to 9 and comparative sample 4 prepared in the weather resistance test 1, the sample 10, the comparative sample 3, and the sample 4 and comparative sample 1 prepared in the chemical resistance test 1 are combined with the xenon weathering. Exposure was made with a meter for 100 hours, 300 hours, and 500 hours, respectively, and the surface resistivity of the antistatic layer before and after exposure was measured with the Hiresta UP to examine whether the weather resistance was good or bad. The results are shown in Table 4 below.

From Table 4, Comparative Sample 4 in which the binder resin of the antistatic layer is made only of polyurethane resin and the adhesive layer is made of urethane-modified polyester having a large absorption in the ultraviolet region is controlled by 100 hours of exposure with the xenon weatherometer. It can be seen that the surface resistivity of the electric layer exceeds 10 ¹⁴ Ω / □ and measurement becomes impossible, and good weather resistance cannot be obtained. On the other hand, the sample 9 in which the antistatic layer was formed by using a mixed resin of polyester resin and polyurethane resin as a binder resin had a surface resistivity of 100 hours of exposure even if the polyester resin accounted for 20 mass%. Compared with the comparative sample 4, the weather resistance is improved to the order of 10 ¹² Ω / □. This is because a polyester resin having good weather resistance is mixed in the binder resin. Further, when comparing Comparative Sample 3 and Samples 5 to 8 in which an acrylic resin adhesive layer is formed, as the mixing ratio of the polyester resin in the binder resin of the antistatic layer increases, the increase in the surface resistivity after exposure decreases. It can be seen that the weather resistance is improved. Further, when comparing Samples 8 and 9, Sample 9 in which the adhesive layer is formed of urethane-modified polyester resin has the adhesive layer formed of acrylic resin, although the binder resin of both antistatic layers is the same. In comparison with Sample 8, the surface resistivity after exposure for 100 hours is considerably increased, and the acrylic resin adhesive layer having a smaller ultraviolet absorption is more effective from the viewpoint of improving the weather resistance than the urethane-modified polyester resin adhesive layer. I understand that.
Note that when Sample 7 and Sample 3, and Samples 8 and 9 and Sample 4 are compared, the adhesive layer is not formed even though the mixing ratio of the polyester resin and the polyurethane resin in the binder resin is the same. It can be seen that Samples 3 and 4 have much less increase in surface resistivity after exposure and significantly improved weather resistance than Samples 7, 8, and 9 with the adhesive layer formed. The reason is presumably because the adhesion between the polyester resin and the base resin is very excellent.

[Weather resistance test 3]
A binder resin in which the water-dispersible acrylic-modified polyester resin and the water-dispersible polyurethane resin are mixed at a mixing ratio shown in Table 5 below, and the PEDOT / An antistatic layer having a thickness of 300 nm containing PSS polymer complex and an ultraviolet absorber shown in Table 5 blended in 8% by mass with the binder resin is disposed on one side of the resin substrate (polycarbonate plate having a thickness of 3 mm). In addition, samples 11 to 19 of the antistatic laminate of the present invention were produced by forming via an adhesive layer having a thickness of 1 μm made of urethane-modified polyester resin.
These samples 11 to 19 were exposed with the xenon weatherometer for 100 hours, 300 hours and 500 hours, respectively, and the total light transmittance and haze of each sample after the exposure were measured with the direct reading haze computer NDH5000. The quality of the sex was examined. The results are shown in Table 5 below. Further, the total light transmittance and haze (explained in Table 3) after the exposure of the sample 9 containing no ultraviolet absorber are also shown in Table 5 below.

  From Table 5, Samples 11 to 14 containing an organic ultraviolet absorber in the antistatic layer are largely different from those of Sample 9 in which the total light transmittance and haze after the exposure do not contain the ultraviolet absorber in the antistatic layer. Although the weather resistance was slightly improved, no significant effect was observed. On the other hand, Samples 15 to 19 containing an inorganic ultraviolet absorber such as cerium oxide or zinc oxide in the antistatic layer are similar to Sample 9 in which the increase in optical properties after exposure, particularly haze, does not include the ultraviolet absorber. Compared with the sample, the effect of significantly improving weather resistance was observed. Samples containing cerium oxide or zinc oxide had a haze value of 8.0 or less after exposure for 300 hours and a haze value of 10% or less after exposure for 500 hours. keeping. From this, it was found that metal oxides such as cerium oxide and zinc oxide are extremely effective in improving weather resistance. In addition, when Samples 15, 18, and 19 containing cerium oxide (average particle size of 10 nm) in the antistatic layer are compared, the haze does not increase as much as the mixing ratio of the polyurethane resin is increased. Since the haze increase is not so great even after time exposure, it can be seen that polyurethane resin is not inferior in weather resistance of optical characteristics such as haze and total light transmittance.

[Weather resistance test 4]
Samples 11 to 19 prepared in the weather resistance test 3 were exposed to the xenon weatherometer for 100 hours, 300 hours, 500 hours, 700 hours, and 1000 hours, and the surface resistance of the antistatic layer before and after the exposure. The rate was measured with the Hiresta UP to examine whether the weather resistance was good or bad. The results are shown in Table 6 below.
For comparison, a comparative sample 5 in which an antistatic layer containing only the polyurethane as a binder resin and containing the same amount of the PEDOT / PSS polymer complex and cerium oxide as described above was prepared, and the comparative sample 5 was controlled as described above. The surface resistivity of the electric layer was measured to check the weather resistance. The results are shown in Table 6 below. Further, the surface resistivity before and after the exposure of the sample 9 that does not contain an ultraviolet absorber (shown in Table 4) is also shown in Table 6 below.

From Table 6, samples 11 to 14 containing an organic ultraviolet absorber in the antistatic layer show an increase in surface resistivity after 100 hours exposure compared to sample 9 in which the antistatic layer does not contain an ultraviolet absorber. Less weather resistance was improved. Samples 15, 17, 18, and 19 containing an inorganic ultraviolet absorber such as cerium oxide or zinc oxide in the antistatic layer show the surface resistivity of the antistatic layer after 100 hours exposure and 300 hours exposure. The increase was small compared to Sample 9 containing no UV absorber and Samples 11 to 14 containing an organic UV absorber in the antistatic layer, and the effect of improving weather resistance was more noticeable. In addition, sample 16 had a surface resistivity of 10 ¹⁴ Ω / □ or more after 300 hours exposure as in sample 9, but the surface resistance after 100 hours exposure was much lower than that of sample 9. After all, the effect of improving weather resistance was observed. From these results, it has been found that metal oxides such as cerium oxide and zinc oxide are extremely effective in improving the weather resistance. In particular, Samples 15, 18, and 19 containing cerium oxide (10 nm) maintain a surface resistivity of the order of 10 ^{11 to 13} Ω / □ even after exposure for 500 hours, and are highly effective in improving weather resistance. It was found that

[IPA wiping resistance test 1]
For the samples 5 to 9 and the comparative sample 4 of the antistatic laminate of the present invention prepared in the weather resistance test 1 and the sample 10 prepared in the weather resistance test 2, the surface of the antistatic layer of each sample is The operation of wiping with a wiping cloth containing IPA was repeated, and the surface resistivity was measured with the Hiresta UP before wiping, after 50 wiping, after 100 wiping, after 200 wiping, and after 300 wiping. The results are shown in Table 7 below.

  According to Table 7, the surface resistance of the antistatic layer after wiping 50 times with a wiping cloth containing IPA, 100 wiping, 200 wiping, and 300 wiping for samples 5 to 10 and comparative sample 4 It can be seen that there is almost no increase in the rate and good IPA wiping resistance.

[IPA wiping resistance test 2]
Samples 11 to 17 of the antistatic laminate of the present invention containing the ultraviolet absorber prepared in the weather resistance test 3, the sample 9 not including the ultraviolet absorber prepared in the weather resistance test 1, and the chemical resistance test. For the samples 3 and 4 that do not contain the UV absorber prepared in 1, the operation of wiping the surface of the antistatic layer of each sample with a wiping cloth containing IPA was repeated, and before wiping, after wiping 50 times, 100 The surface resistivity after each wiping, 200 wiping, and 300 wiping was measured with the Hiresta UP. The results are shown in Table 8 below.

From Table 8, all of Sample 9, Samples 11-17, and Samples 3 and 4 were wiped with a wiping cloth containing IPA 50 times, after 100 times, after 200 times, after 300 times. It can be seen that there is almost no increase in the surface resistivity of the layer and it has good IPA wiping resistance. And when the samples 9, 4, and 3 in which the antistatic layer does not contain the ultraviolet absorber and the samples 11 to 17 in which the antistatic layer contains the ultraviolet absorber, the former has a surface resistivity of 10 after wiping 300 times. ^While the latter has an order of ^7-8 Ω / □, the latter has a surface resistivity after wiping 300 times of 10 ⁸ Ω / □, which is not much different from the former. It can be seen that it does not adversely affect

[Weather resistance test 5]
A binder resin obtained by mixing the water-dispersible acrylic-modified polyester resin and the water-dispersible polyurethane resin at a mixing ratio shown in Table 9 below, and the PEDOT / PSS blended in the binder resin by 6% by mass as a conductive polymer. An antistatic layer having a thickness of 300 nm containing a polymer complex and cerium oxide (10 nm) compounded by 8% by mass as an ultraviolet absorber in the binder resin is formed on one side of the resin base material (polycarbonate plate having a thickness of 3 mm). Samples 20 to 25 of the antistatic laminate of the present invention were produced by forming directly or through a 1 μm thick adhesive layer made of a vinyl chloride-vinyl acetate copolymer.
These samples 20 to 25 were exposed to the xenon weatherometer for 100 hours, 300 hours, 500 hours, 700 hours, and 1000 hours, and the surface resistivity of the antistatic layer of samples 20 to 25 before and after the exposure was measured as described above. It was measured with Hiresta UP to examine whether the weather resistance was good or bad. The results are shown in Table 9 below. The surface resistivity of Samples 15, 18, 19 and Comparative Sample 5 are also shown in Table 9 below.
Further, with respect to an adhesive layer made of a vinyl chloride-vinyl acetate copolymer resin having a thickness of 3 μm and an adhesive layer made of a urethane-modified polyester resin having a thickness of 3 μm, UV absorbance in a wavelength region of 200 to 500 nm was measured using a UV absorbance meter (( It was measured using Shimadzu Corporation UV-3100PC). The result is shown in the graph of FIG.

From Table 9, the comparative sample 5 using only the polyurethane resin as the binder resin of the antistatic layer has a surface resistivity of 10 ¹⁴ Ω / □ or more after 300 hours exposure, whereas the mixed resin of polyurethane resin and polyester resin. It can be seen that Samples 15 and 18 to 25 having a binder resin have improved weather resistance as compared with Comparative Sample 5, and the increase in the surface resistivity tends to decrease as the mixing ratio of the polyester resin increases. In particular, Samples 20, 21, 22, and 23 without an adhesive layer maintain a surface resistivity of 10 ⁹ Ω / □ or less even after 300 hours of exposure, and have excellent weather resistance. Street.

  Further, when the samples 15, 18 and 19 are compared with the samples 24 and 25, an adhesive layer made of a vinyl chloride-vinyl acetate copolymer resin having little absorption in the ultraviolet region (200 to 400 nm) as shown in the graph of FIG. The provided samples 24 and 25 have lower surface resistivity before and after the exposure than the samples 15, 18 and 19 provided with an adhesive layer made of urethane-modified polyester resin that absorbs much in the ultraviolet region. It can be seen that an adhesive layer made of a vinyl chloride-vinyl acetate copolymer resin having little absorption in the ultraviolet region is excellent in weather resistance.

  From the results of the above weather resistance tests, in the antistatic laminate having an adhesive layer between the resin base material and the antistatic layer, urethane resin, acrylic resin, vinyl chloride-vinyl acetate are used as the resin for the adhesive layer. Although a polymer resin can be used, it can be seen that a vinyl chloride-vinyl acetate copolymer resin having a small absorption in the ultraviolet region is preferably used. It can also be seen that the inclusion of the polyester resin in the binder resin improves the adhesion between the resin base material and the antistatic layer even if the adhesive layer is omitted, and provides excellent weather resistance. And the antistatic laminated body of the 2 layer structure only of a resin base material and an antistatic layer can also obtain effects, such as cost reduction, thickness reduction, and a shortening of a manufacturing process, by lose | eliminating an adhesive layer.

[Binder resin selection test]
The water dispersible acrylic modified polyester resins (A515GE), (A215GE), unmodified polyester resins (A120), (A510), (A520) manufactured by Takamatsu Yushi Co., Ltd. listed in Table 10 below, and these binder resins An antistatic layer having a thickness of 300 nm containing 6% by mass of the PEDOT / PSS polymer complex as a main component is formed on one side of the resin substrate (a polycarbonate plate having a thickness of 3 mm), and five types of samples are formed. Was made. In addition to examining the appearance of each sample and the moldability of the antistatic layer, for samples using A515GE as the binder resin for the antistatic layer and for samples using A520 as the binder resin for the antistatic layer, these antistatic layers include IPA. The surface resistivity after each wiping cloth was measured by the Hiresta UP before wiping, after wiping 50 times, after wiping 100 times, after wiping 200 times, and after wiping 300 times. The results are shown in Table 10 below.
Further, the water dispersible polyurethanes (Flex 170), (Flex 130), (Flex 420), (Flex 650) manufactured by Daiichi Kogyo Seiyaku Co., Ltd. listed in Table 10 below, and 6% by mass in these binder resins An antistatic layer having a thickness of 300 nm containing the blended PEDOT / PSS polymer complex as a main component is formed on one side of the resin base material, and four types of samples different from the above are prepared. In addition, the appearance of each sample and the moldability of the antistatic layer were examined, and the surface resistivity after wiping IPA was measured for each of the samples having Flex 170 and Flex 130 having a glass transition point of 0 ° C. or more as binder resins. The results are also shown in Table 10 below.

  From Table 10, the sample using acrylic modified polyester resin (A515GE) or non-modified polyester resin (A520) as the binder resin of the antistatic layer shows the surface resistivity of the antistatic layer even after repeating IPA wiping 300 times. There is almost no increase, the IPA wiping resistance is good, and the sample using any polyester resin has good moldability of the antistatic layer. However, in terms of appearance, samples using acrylic modified polyester resins (A515GE) and (A215GE) are good, and samples using unmodified polyester resins (A120), (A510), and (A520) tend to cause whitening. It was observed. As a result, any polyester resin can be used as one component of the binder resin of the antistatic layer, but among them, a modified polyester resin is preferable, and an acrylic modified polyester resin is particularly suitable. It has also been found that the glass transition point of the polyester resin is preferably 0 ° C. or higher.

  On the other hand, a sample using a water-dispersible polyurethane resin (Flex 170) or (Flex 130) having a glass transition point of 0 ° C. or higher (70 to 120 ° C.) as a binder resin is effective even after IPA wiping is repeated 300 times. Polyurethane resin (flex 420) having a glass transition point lower than 0 °, although the surface resistivity of the layer is hardly increased and the IPA wiping resistance is good and the antistatic layer has good appearance and moldability. ), A sample using (Flex 650) as a binder resin showed a tendency to gel when the conductive polymer PEDOT / PSS was mixed, and the moldability was not good. From this, it was found that any polyurethane resin can be used as the other component of the binder resin of the antistatic layer, and among them, a water dispersible polyurethane resin having a glass transition point of 0 ° C. or higher is preferable.

  As supported by the results of the above chemical resistance test, weather resistance test, and IPA wiping resistance test, the antistatic laminate of the present invention has good chemical resistance, weather resistance, IPA wiping resistance, and has a long-term It is an excellent laminate that can maintain antistatic properties.

1 Resin base material 2 Antistatic layer 3 Adhesive layer

Claims (4)

An antistatic laminate having a resin base and an antistatic layer formed on at least one side of the resin base,
The antistatic layer is a layer mainly composed of a conductive polymer and a binder resin, the binder resin is a mixed resin of a polyester resin and a polyurethane resin, and the surface resistivity of the antistatic layer is less than 10 ⁹ Ω / □. An antistatic laminate characterized by that.   2. The antistatic laminate according to claim 1, wherein a mixing ratio of the polyester resin and the polyurethane resin is 1: 9 to 8: 2 by mass ratio.   The antistatic laminate according to claim 1, wherein the antistatic layer contains an ultraviolet absorber.   The antistatic laminate according to claim 3, wherein the ultraviolet absorber is zinc oxide and / or cerium oxide.

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