JP2003231200A - Antistatic transfer foil - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To give antistatic performance while excellent transparency is secured. <P>SOLUTION: With regard to antistatic transfer foil 10 with at least a transparent conductive layer 3 laminated as a transparent transfer layer 2 on a support sheet 1, the transparent conductive layer is made a layer in which transparent conductive powder of needle-shaped tin oxide powder is dispersed in a resin binder. A transparent adhesive layer 4 and a transparent resin layer 5 to be the outermost surface after transfer can be formed on the transfer layer 2. Even in the same tin oxide powder as the transparent conductive powder, in the needle-shaped powder as compared with spherical powder, an improved conductivity is obtained by the addition of a small amount of the powder. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an LCD in various electric devices such as a remote controller of a television.
The present invention relates to a transfer foil capable of imparting antistatic performance to various articles such as window materials for display parts using the above.

[0002]

2. Description of the Related Art In recent years, LCD (liquid crystal display)
The spread of display panels represented by is remarkable. For example, in addition to applications such as monitor displays for personal computers and display devices such as large-sized liquid crystal televisions, devices that employ a display panel as a display unit, for example, various audio devices such as VCRs, CD players, MD players, etc., can be operated remotely. Remote controller, home appliances such as washing machines, refrigerators, air conditioners, rice cookers, or
Display panels have come to be used in various applications such as portable MD players, video cameras, various mobile devices such as mobile phones, and other electrical devices.

By the way, among these, in display devices such as a monitor display and a large-sized liquid crystal television, there are many structures in which the display panel itself is directly exposed to the outer surface, but other devices such as the above-described audio device, remote controller, In many household appliances, mobile devices, etc., a window member made of a transparent resin plate or the like is arranged in front of a display panel such as an LCD in order to protect it from dust, external force, water and the like.

In many cases, these various electric devices are required to have antistatic performance. This is because electrostatic charging causes dust to adhere and malfunction of the device.
Therefore, conventionally, a coating film of a conductive paint containing a conductive powder such as carbon black or metal powder is formed. However, when the article imparting antistatic performance is an article requiring transparency such as the window material, an opaque conductive coating using carbon black or the like is not suitable because the transparency is impaired. . Then, JP-A-57-8586
For example, Japanese Patent No. 6 discloses the use of a transparent conductive coating material using tin oxide fine powder having a particle size of 0.2 μm or less for applications requiring such transparency. However, when a coating film is formed by using a paint, solvent drying is required and workability and productivity are poor. In addition, it cannot be applied to resins that dissolve in paint solvents. When such workability and productivity are problems, a coating film made of a transparent conductive paint is prepared as a transfer layer of a transfer foil as disclosed in JP-A-2-208024 and the like. This can be solved by adopting the method of forming the transparent conductive layer.

[0005]

However, although the use of tin oxide powder in the conductive coating material ensures the transparency, there is a slight decrease in the transparency. In applications where the article is transparent and one can see through it, the decrease in transparency due to the antistatic treatment has been a problem to be avoided as much as possible.

That is, an object of the present invention is to make it possible to impart antistatic performance while ensuring excellent transparency.

[0007]

In order to solve the above problems, the present invention invented an antistatic transfer foil for imparting antistatic performance by transfer. That is, the antistatic transfer foil of the present invention is an antistatic transfer foil formed by laminating at least a transparent conductive layer as a transparent transfer layer on a support sheet, wherein the transparent conductive layer is made of acicular tin oxide powder. The transparent conductive powder is formed into a layer in which the transparent conductive powder is dispersed in a resin binder.

By using the antistatic transfer foil having such a constitution, even if the same tin oxide powder as the transparent conductive powder has a needle-shaped powder, a small amount of addition will give a larger conductivity as compared with the case where the powder has a spherical shape. Is obtained. As a result, the antistatic performance can be imparted in a more excellent state of transparency. Moreover, since the transfer layer including the transparent conductive layer after transfer can be made into a smooth surface having excellent specularity as compared with the case where antistatic is performed by coating, an image that can be seen by transmission or reflection due to surface irregularities such as a coated surface is formed. There is no distortion. Therefore, for example, when applied to a window material or the like of a display unit such as a display, the visibility of the display is not impaired.

In addition, the antistatic transfer foil of the present invention has the above-mentioned structure in which a transparent adhesive layer is further laminated on the transparent conductive layer as a transfer layer.

With such a structure, even if the material of the transparent conductive layer as the transfer layer is difficult to adhere to the article to be the transfer target, it can be easily adhered and transferred by the transparent adhesive layer. In addition, the transfer layer can be freely transferred to the surface of the transfer target without applying an adhesive to the transfer target side or using an adhesive thermoplastic resin as a component of the transparent conductive layer of the transfer layer. It is possible to transfer the material, and the degree of freedom in selecting the material of the transfer layer and the range of application of the article can be expanded.

Further, the antistatic transfer foil of the present invention has a structure in which, in any one of the above structures, a transparent resin layer is further provided as a transfer layer so as to be in contact with the support sheet.

With such a structure, the transparent resin layer serves as a release layer for improving the releasability between the support sheet and the transfer layer, or for improving the surface strength of the transfer layer surface after transfer. It can be used as a hard coat layer, an uneven pattern layer on the surface of a transfer layer after transfer, or a layer that combines two or more of these, and only one transparent conductive layer is required without exhibiting these performances. It is possible to easily obtain various physical properties such as completeness, transferability and surface strength in a well-balanced manner.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below.

[Outline] First, FIG. 1 illustrates some of the embodiments of the antistatic transfer foil of the present invention. In the antistatic transfer foil 10 of the present invention illustrated in FIG. 1 (A), a transparent conductive layer 3 is laminated as a transfer layer 2 on a support sheet 1, and the transparent conductive layer 3 is needle-shaped oxidized. The transfer foil has a structure in which tin powder is dispersed in a resin binder as a transparent conductive powder.

The transfer layer 2 is composed of at least the transparent conductive layer 3 described above, and further, for example, as shown in FIGS.
A configuration including another layer may be adopted as in the embodiment shown in (D). The antistatic transfer foil 10 illustrated in FIG.
In contrast to the configuration of (A), a transparent adhesive layer 4 is further laminated on the transparent conductive layer 3 as the transfer layer 2, and it is easy to obtain the adhesiveness to the transfer target, is there.
In addition, the antistatic transfer foil 10 illustrated in FIG.
In addition to the configuration of (A), a transparent resin layer 5 is further laminated as the transfer layer 2 so as to be in contact with the support sheet 1 below the transparent conductive layer 3, that is, the support sheet 1 side. This is a preferable mode because it is easy to adjust the peeling force at the time of transfer, protect the surface of the transfer layer after transfer, and improve the surface strength. In addition, the antistatic transfer foil 10 illustrated in FIG.
In addition to the structure of FIG.
The transparent adhesive layer 4 is laminated on the transparent conductive layer 3 to form the transfer layer 2
Is a configuration example having three layers of the transparent resin layer 5, the transparent conductive layer 3 and the transparent adhesive layer 4 from the support sheet 1 side, and the above-mentioned respective effects by the transparent adhesive layer 4 and the transparent resin layer 5 are It is a preferable form because it can be obtained.

And as an antistatic treatment for various articles,
By transferring the transparent transfer layer 2 from the antistatic transfer foil 10 as described above as a transfer target using a base material forming an article, for example, as shown in FIG. An antistatic article 20 having a structure in which the transparent conductive layer 3 is laminated is obtained. The mochiro and the antistatic processed surface may be a plurality of two or more surfaces, and the antistatic article 20 illustrated in FIG.
This is a configuration example in which the transparent conductive layer 3 is laminated on the front and back surfaces of the plate-shaped substrate 6. Since FIG. 2 is also a sectional view conceptually showing the antistatic article 20, the layers laminated on the surface of the base material 6 are similar to those in FIG.
Although only the transparent conductive layer 3 corresponding to the antistatic processing by the antistatic transfer foil 10 of (A) is shown in FIGS.
(C), or a layer corresponding to the antistatic transfer foil 10 of FIG. 1D may be laminated. For example, FIG. 3 (A)
The antistatic article 20 of No. 1 is an example of a configuration in which the transparent adhesive layer 4 and the transparent conductive layer 3 are laminated on the base material 6, and FIG.
Is a configuration example in which the transparent adhesive layer 4, the transparent conductive layer 3, and the transparent resin layer 5 are laminated on the substrate 6. In order to transfer the transfer layer from the antistatic transfer foil to the surface of the substrate, various conventionally known transfer methods such as a roll transfer method (roller transfer method), an up-down transfer method, and an injection molding simultaneous transfer method are appropriately used. You can use it.

The antistatic transfer foil of the present invention will be described below.
The layers will be described in detail in order.

[Support Sheet] The support sheet 1 is appropriately selected from known materials without any limitation.
For example, (a) polyethylene terephthalate (PE
T), thermoplastic resins such as polybutylene terephthalate (PBT), polyethylene naphthalate (PEN), polyester resins, polyolefin resins such as polyethylene, polypropylene, polymethylpentene, olefinic thermoplastic resin elastomers, polyvinyl chloride, polycarbonate, polystyrene , ABS resin, acrylic resin, polyether sulfone (PES), polyether ether ketone (PEEK) and other resin sheets, (b) thin paper, fine paper, paper such as coated paper, (c) aluminum, iron, copper, etc. It is a sheet (film) of metal foil or the like. The thickness of the support sheet is usually about 20 to 200 μm. Further, as the support sheet, when transferring the antistatic transfer foil, heat is usually applied to the transfer sheet, such as a roll transfer method, an up-down transfer method, and an injection molding simultaneous transfer method.
Assuming such a case, a material having heat resistance is preferable so that it does not expand or contract or the uneven shape is not deformed. Among the materials listed above, examples of materials having excellent heat resistance include:
Examples of the resin material include PET, PEN, PES, PEEK, and the like, and metal and the like are also excellent.

If necessary, the support sheet may be provided with a release layer on the transfer layer side as a component of the support sheet in order to improve the peelability from the transfer layer. When the support sheet is peeled off, the release layer is peeled and removed from the transfer layer as a part of the support sheet with respect to the transfer layer that moves to the transfer target side. As the release layer, for example, a silicone resin, a melamine resin, a polyamide resin, a urethane resin, a polyolefin resin, an ionizing radiation curable resin, a wax or the like alone or a mixture containing these is used. Further, in order to adjust the releasability, the surface of the support sheet on the transfer layer side may be subjected to corona discharge treatment, ozone treatment or the like.

If necessary, the support sheet may be provided with an uneven pattern on the surface on the transfer layer side, so that the surface of the transfer layer after transfer has an uneven pattern such as sand, satin or wood grain. Or
You can also adjust the surface gloss. The concavo-convex pattern can be formed by a known method such as embossing, sandblasting, and swelling printing with a shaping layer (release layer). Of course, when applied to the window material of the display,
An uneven pattern is formed on a portion that does not interfere with the visual confirmation of the display, or an uneven pattern that does not interfere.

[Transfer Layer: Transparent Conductive Layer] Transparent transfer layer 2
In the present invention, the transparent conductive layer 3 which is an indispensable layer is a layer in which excellent transparency is obtained together with the conductivity required for antistatic. It is formed as a layer dispersed as a powder in a resin binder.

In general, fine powders of tin oxide and ITO are typical as the transparent conductive powder. In particular, in the present invention, the tin oxide powder having a needle-like particle shape is used to impair conductivity and transparency. Can be given without. That is, compared with the case where the particle shape is spherical, the tin oxide powder having a needle-like particle shape can obtain conductivity with a smaller addition amount, and therefore, the transparency is also more excellent. In particular, in the case where the article to be treated with the antistatic transfer foil is required to have transparency and visibility of the display such as the window material of the display section as described in the above-mentioned prior art, this transparency is particularly important. It is a basic performance element. The particle size of the transparent conductive powder such as tin oxide powder may be any size as long as transparency is obtained, and the average particle size is usually 0.
A powder of 4 μm or less is used. For example, in the case of a sphere, it is 0.
It is about 01 to 0.03 μm. In the case of a needle shape, for example, the short axis is about 0.01 to 0.02 μm, and the long axis is about 0.2 to 2.0 μm. Needless to say, the tin oxide powder used as the transparent conductive powder contains a slight amount of impurities such as antimony (doped) in order to make the powder conductive.

In the present invention, the transparent conductive layer for imparting the antistatic property is formed by transfer, so that the surface is flattened like a mirror surface as compared with the case where the transparent conductive layer is formed by painting. It becomes possible. Therefore, when applied to the window material of the display, etc.
Distortion does not easily occur in the display image and visibility is not reduced.

On the other hand, as the resin binder, a resin suitable for the application may be used without any particular limitation. For example, as the resin binder, various types of thermoplastic resins such as cellulosic resins such as nitrocellulose, ethyl cellulose, hydroxyethyl cellulose, acrylic resins, vinyl acetate resins, thermoplastic urethane resins, polyester resins, polyvinyl alcohol resins, or urethane resins. , Various curable resins such as epoxy resin, melamine resin, alkyd resin, and phenol resin. The transparent conductive layer made of these materials is roll-coated with a coating (or ink) containing needle-shaped tin oxide powder and a resin binder,
It can be formed by a known coating method such as various coating methods such as gravure coating and various printing methods such as silk screen printing and flexographic printing.

Depending on the structure of the transfer layer 2, the transparent conductive layer 3 may or may not be exposed as the outermost surface layer of the transfer layer after transfer [FIG. 1 (A), FIG.
(D), FIG. 3 (A), FIG. 3 (B), etc.] In any case, as the antistatic performance, the surface resistivity of the transfer layer surface after transfer is usually 10 ⁷ to 10 depending on the application. ⁹ Ω / □
It can be obtained by reducing it to a certain degree. Therefore, the conductivity of the transparent conductive layer may be adapted accordingly. For example, the addition amount of the needle-shaped tin oxide powder is about 10 to 70% by mass with respect to the total amount of the resin and the tin oxide powder, although it depends on the required antistatic performance, the layer structure and the like. The thickness of such a transparent conductive layer depends on the application but is usually about 1 to 10 μm. If the addition amount or the thickness is too small, sufficient antistatic performance cannot be imparted, and if the addition amount or the thickness is too large, the transparency is lowered, the haze value is increased, and the cost is increased. In particular, when it is applied to a window material of a display portion, the haze value (%) (JIS K710
5) is preferably 3.0 or less.

Generally, as the transparent conductive layer, a conductive metal thin film made of gold or the like formed by a physical forming method such as vapor deposition or sputtering, or a conductive metal oxide thin film made of ITO (indium tin oxide) or the like is used. Etc., or a coating film in which an antistatic agent of various cationic or nonionic surfactants is dispersed in a resin binder, but when using a thin film, productivity is low, and when using an antistatic agent, aging There is a problem of performance degradation due to static bleed-out. However, the transparent conductive layer according to the present invention is superior to these in that the productivity is good and there is no deterioration in performance over time.

[Transfer Layer: Transparent Adhesive Layer] Transparent Adhesive Layer 4
Is preferably provided when it is difficult for the transparent conductive layer 3 itself to be directly adhered to the transferred material, or in that case, when the adhesive is not applied to the transferred material. The adhesive used for the transparent adhesive layer is not particularly limited as long as it is transparent and has adhesiveness between the transparent conductive layer and the transferred material. Usually, since the adhesiveness at the time of transfer is based on heat fusion that causes heat, a thermoplastic resin is typically used as the adhesive. However, even a thermosetting resin, an ionizing radiation curable resin, or the like can be heat-sealed on the antistatic transfer foil as long as it exhibits thermoplasticity before complete curing. Therefore, such a thermosetting resin or ionizing radiation curable resin can also be used. In addition, when adhesiveness can be expected in the case where a resin exhibiting thermoplasticity such as a thermoplastic resin is used for the resin binder of the transparent conductive layer at least at the time of transfer, the transparent conductive layer is the transparent adhesive layer. It can also be regarded as a layer that doubles as.

As the adhesive used for the transparent adhesive layer as described above, for example, acrylic resin, polycarbonate resin,
Examples thereof include polyolefin resins, thermoplastic resins such as vinyl chloride-vinyl acetate copolymers, thermosetting resins such as polyurethane resins and epoxy resins, and ionizing radiation curable resins that are cured by ultraviolet rays or electron beams. In order to further form the transparent adhesive layer on the transparent conductive layer, a known coating method such as roll coating may be used. The thickness of the transparent adhesive layer is usually about 1 to 10 μm.

[Transfer Layer: Transparent Resin Layer] The transparent resin layer 5 is
It is provided as a layer of the transfer layer which is in contact with the support sheet 1, and is a layer which becomes the outermost surface layer of the transfer layer 2 after the transfer. Although the transparent resin layer can be omitted, by providing this transparent resin layer, the antistatic performance is exclusively carried by the transparent conductive layer, and the other required performance as the transfer layer is also carried by this transparent resin layer. By sharing, the degree of freedom in selecting the material of the transfer layer can be increased. Specifically, the transparent resin layer is, for example, a peeling force adjustment between the support sheet and the transfer layer, or a concavo-convex pattern layer for adjusting the gloss of the transfer layer surface after transfer and improving the design, or a transfer layer. It can be used as a hard coat layer to protect the surface of the transfer layer afterwards or to improve the surface strength, and it is not necessary to provide these properties together with the antistatic property with only one transparent conductive layer. , Various physical properties such as surface strength can be easily obtained with good balance. When a transparent resin layer is provided as the hard coat layer, examples of the resin include thermosetting resins such as urethane resins and epoxy resins, and ionizing radiation curable resins such as acrylates that are cured by ultraviolet rays or electron beams. When formed as a crosslinked cured product of a curable resin, excellent performance can be obtained.

As the resin of the transparent resin layer, at least
It is preferable to select a transparent resin that can be peeled (released) from the above-mentioned support sheet and that fulfills the above-mentioned function of being carried by the transparent resin layer depending on the application.

Therefore, as the transparent resin used for the transparent resin layer, for example, acrylic resin, polycarbonate resin,
Polyolefin resin, thermoplastic resin such as vinyl chloride-vinyl acetate copolymer, thermosetting resin such as polyurethane resin, epoxy resin, melamine resin, or ionizing radiation curable resin that is cured by ultraviolet rays or electron beams. To be The transparent resin layer may be formed on the support sheet by a known coating method such as roll coating.
The thickness of the transparent resin layer is usually about 1 to 10 μm.

The ionizing radiation-curable resin is a composition curable by ionizing radiation, and specifically, a prepolymer having a radically polymerizable unsaturated bond or a cationically polymerizable functional group in the molecule. A composition curable by ionizing radiation (which includes so-called oligomers) and / or a monomer is appropriately used is preferably used. These prepolymers or monomers are used alone or in combination of two or more.

The above-mentioned prepolymer or monomer specifically has a radically polymerizable unsaturated group such as a (meth) acryloyl group and a (meth) acryloyloxy group, a cationically polymerizable functional group such as an epoxy group, etc. in the molecule. Consisting of a compound having. In addition, a polyene / thiol-based prepolymer obtained by combining polyene and polythiol is also preferably used. In addition, for example, a (meth) acryloyl group is
It means an acryloyl group or a methacryloyl group. Further, the following (meth) acrylate also means acrylate or methacrylate. Examples of the prepolymer having a radically polymerizable unsaturated group include polyester (meth) acrylate, urethane (meth) acrylate, epoxy (meth) acrylate and melamine (meth).
Acrylate, triazine (meth) acrylate, silicone (meth) acrylate and the like can be used. A molecular weight of about 250 to 100,000 is usually used.

As an example of the monomer having a radical-polymerizable unsaturated group, a monofunctional monomer such as methyl (meth) is used.
There are acrylate, 2-ethylhexyl (meth) acrylate, phenoxyethyl (meth) acrylate and the like.
Further, as a polyfunctional monomer, diethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, trimethylolpropane tri (meth)
There are also acrylate, trimethylolpropane ethylene oxide tri (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate and the like. Examples of the prepolymer having a cationically polymerizable functional group include prepolymers of epoxy resins such as bisphenol type epoxy resins and novolac type epoxy compounds, and vinyl ether type resins such as fatty acid vinyl ethers and aromatic vinyl ethers. Examples of thiols include polythiols such as trimethylolpropane trithioglycolate and pentaerythritol tetrathioglycolate. In addition, as the polyene, there is a polyene in which allyl alcohol is added to both ends of polyurethane made of diol and diisocyanate.

In the case of curing with ultraviolet rays or visible light, a photopolymerization initiator is further added to the above ionizing radiation curable resin. In the case of a resin system having a radically polymerizable unsaturated group, acetophenones, benzophenones, thioxanthones, benzoin, benzoin methyl ethers can be used alone or as a mixture as a photopolymerization initiator. In the case of a resin system having a cationically polymerizable functional group, an aromatic diazonium salt, an aromatic sulfonium salt, an aromatic iodonium salt, a metallocene compound, a benzoin sulfonic acid ester, or the like is used alone or as a mixture as a photopolymerization initiator. be able to. In addition,
The addition amount of these photopolymerization initiators is about 0.1 to 10 parts by mass with respect to 100 parts by mass of the ionizing radiation curable resin.

As the ionizing radiation, an electromagnetic wave or charged particles having energy capable of causing a curing reaction of molecules in the ionizing radiation curable resin (composition) is used. Usually used are ultraviolet rays or electron beams, but in addition,
It is also possible to use visible light, X-rays, ion rays and the like.
As the ultraviolet ray source, a light source such as an ultra-high pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a carbon arc lamp, a black light, and a metal halide lamp is used. As a wavelength of ultraviolet rays, a wavelength range of 190 to 380 nm is usually mainly used. As the electron beam source, various electron beam accelerators such as Cockcroft-Walton type, Van de Graft type, resonance transformer type, insulating core transformer type, linear type, dynamitron type, high frequency type, etc. are used, preferably 100 to 1000 keV. Is used to irradiate electrons having an energy of 100 to 300 keV.

Further, in order to adjust the physical properties such as flexibility, surface hardness and peelability, the ionizing radiation curable resin may further contain urethane resin, cellulose resin, polyester resin, acrylic resin, if necessary. A thermoplastic resin such as a system resin, a butyral resin, a vinyl chloride-vinyl acetate copolymer, polyvinyl acetate, or polyvinyl chloride can also be added.

[Form of Antistatic Transfer Foil] By the way,
The antistatic transfer foil of the present invention may be in the form of a single sheet, but if it is in the form of a continuous strip, the antistatic transfer foil can be easily used continuously and is preferable in terms of productivity in antistatic processing. Each layer of the transfer layer such as the transparent conductive layer on the support sheet may be formed by sequentially forming each layer on the support sheet by a known method such as coating described above. When the transfer layer has a multi-layered structure, a conventionally known primer layer made of urethane resin, silane coupling agent, or the like may be appropriately provided between the layers to improve interlayer adhesion. When a transparent resin layer and a transparent adhesive layer are also provided, needle-shaped tin oxide powder may be contained in these layers as in the case of the transparent conductive layer. In other words, the antistatic property is mainly carried out by the transparent conductive layer, but the transparent resin layer and the transparent adhesive layer are also made conductive to a certain extent in an auxiliary manner.

[Transfer Processing Method Using Antistatic Transfer Foil]
The transfer processing method for imparting antistatic performance to an article to be transferred using the antistatic transfer foil of the present invention is not particularly limited, and it is conventional in the transfer technical field depending on the application. Various known transfer methods may be adopted. For example, (1) a roll transfer method of applying pressure with a roller pressure, (2) an up-down transfer method of applying a flat plate shape, (3) an injection molding simultaneous transfer method of applying an injection pressure, or the like may be adopted. (3)
The transfer method is a method capable of transferring simultaneously with molding of the article as disclosed in JP-A-6-315950, JP-B-2-42080, etc., but in that an antistatic article having a complicated shape can be obtained. It is also preferable in terms of high productivity because molding and transfer processing of the article can be performed in one step. On the other hand, the transfer methods (1) and (2) are performed on an article that already has a shape, and (3) the material of the article is limited to resin, whereas injection molding such as glass is performed. This is a transfer method that can be applied to materials that are not suitable for. The transfer is usually performed by applying heat in addition to the pressure.

The case where the injection molding simultaneous transfer method is adopted as the transfer method will be further described as follows. In the case of the injection molding simultaneous transfer method, the antistatic transfer foil as described above is arranged in a pair of injection molding dies (both male and female) with the transfer layer side facing the resin for molding the base material of the article. Then, both injection molding dies are engaged and clamped, the resin in a fluid state is injected and filled into the cavity formed between the two dies, and the injected resin is brought into contact with the transfer layer, and then the resin is solidified. After that, both molds are opened, and the support sheet is peeled from the solidified resin, so that only the transfer layer having the transparent conductive layer is transferred to the substrate surface made of the solidified resin. An antistatic article having a structure in which a transfer layer including a transparent conductive layer is laminated on a substrate is obtained. In this way, antistatic performance is imparted simultaneously with the molding of the substrate of the article. Further, according to this transfer method, there is an advantage that an antistatic article can be obtained with high productivity.

In the injection molding simultaneous transfer method, the antistatic transfer foil is used not as a single sheet but as a continuous strip, so that a new antistatic transfer foil is continuously introduced into the injection mold every shot of injection molding. It can be easily supplied and discharged (as a support sheet after peeling). Supplying continuous strip-shaped sheets to injection molding dies like this
Regarding the discharge method, in the technical field of decoration of resin molded products,
For example, the technique disclosed in Japanese Patent Laid-Open No. 6-315950 can be used.

During transfer processing using the antistatic transfer foil, the support sheet is not peeled immediately after the antistatic transfer foil is laminated on the surface of the transfer target (base material), and the support sheet is removed. It may be left as a protective film or the like.
The remaining support sheet is peeled off at an appropriate time such as immediately before using the antistatic article. Further, the transfer application surface is a flat surface, which is easy to transfer, but is not limited to this, and may be a curved surface if it is loose.

[Antistatic Article] The antistatic article 20 obtained by transferring the above antistatic transfer foil has at least the transparent conductive layer 3 on the base material 6 as illustrated in the cross-sectional views of FIGS. 2 and 3. It is an article having a laminated structure. The transparent conductive layer 3 is a layer in which the above-mentioned acicular tin oxide powder is dispersed in a resin binder. By forming the transparent conductive layer 3 as a layer laminated by transfer, the surface is excellent in smoothness and the visibility of the display is also good when applied to the window material of the display section. As shown in FIGS. 2 (A) and 2 (B), the antistatic article 20 has at least the transparent conductive layer 3 laminated on the base material 6, and FIGS. 3 (A) and 3 (B).
As illustrated in, the transparent adhesive layer 4 / transparent conductive layer 3 or the transparent adhesive layer 4 / transparent conductive layer 3 /
Transparent resin layer 5, or transparent conductive layer 3 / transparent resin layer 5
And so on. In each case, the above-mentioned effects described for the antistatic transfer foil can be obtained. The shape of the antistatic article 20 may be a film (or a sheet), a plate, a three-dimensional shape, or the like, and may have various shapes depending on the application. For example, as a specific example of the thickness of the base material in the form of a flat plate, it is usually about 0.5 to 2 mm for applications such as window materials for the display unit. In addition,
The antistatic processed surface according to the present invention may be, for example, a front side or a back side if it is a plate. Also, the antistatic processed surface is
Instead of one surface as illustrated in FIG. 2, a plurality of surfaces may be used.

As the material of the base material 6 of the antistatic article, a material suitable for the application is used. The base material is a multi-layered structure, a structure having other constituent elements, or the like depending on the application, depending on the application. The substrate is opaque or transparent. As the material of the base material, in addition to organic materials such as resins, inorganic materials such as glass are used. For example, in the case of the window material for the display section described in the prior art, it is transparent and resin is common.

For example, as a transparent resin material used for the substrate, a thermoplastic resin is typical, and examples thereof include poly (meth) acrylate, poly (meth) acrylate, and methyl (meth) acrylate. Acrylic resin such as butyl (meth) acrylate copolymer [wherein (meth) acrylic means acrylic or methacrylic]. ], Polycarbonate resin, polypropylene, polymethylpentene, cyclic olefin polymer (typically, norbornene resin, etc., but for example, product name "Zeonor" manufactured by Nippon Zeon Co., Ltd., "Arton" manufactured by JSR Co., Ltd. "
Etc.) polyolefin resin such as, polyethylene terephthalate, thermoplastic polyester resin such as polyethylene naphthalate, polyamide resin, polystyrene, acrylonitrile-styrene copolymer, polyether sulfone, polysulfone, cellulose resin, vinyl chloride resin, Examples include polyether ether ketone and polyurethane.

Particularly when the transfer method is the injection molding simultaneous transfer method, a thermoplastic resin is used for the substrate. In addition, when the transfer method is a method such as a roll transfer method or an up-down transfer method performed on a substrate having an already formed shape, an inorganic material such as glass can be used.

[Application of Antistatic Article] The antistatic article obtained by using the present invention may have any shape such as a film (or sheet), a plate, and a three-dimensional shape, and its application is also particularly limited. Not.

The application of the antistatic article is, for example, various audio equipment such as a CD player, a DVD player, an MD player, a VCR, a remote controller for remotely operating these audio equipment, a television, an air conditioner or the like, or a video camera. , Video equipment such as digital cameras, refrigerators, electric rice cookers, electric kettles, home appliances such as washing machines, CD players, DVD players, MDs
Players, semiconductor memory type music players, IC recorders, mobile phones, personal computers, electronic notebooks and other PDAs, portable information terminals and other portable devices, IC recorders, label printers and other electronic devices, and other display devices. Window material.

In these display units, a resin window material such as a plate or a molded product is arranged in front of a display panel such as an LCD. In the antistatic article as the window material, the inner surface side may be the application surface. In addition to the display panel such as an LCD, the display unit may be a unit for displaying by a mechanical means such as a mechanical analog meter typified by a timepiece, or a window material thereof. The window material has a flat plate shape, but may have a projection or the like around it from the viewpoint of assembly and design.

In the case of sheet (or film) or plate-shaped antistatic articles, transparent base materials such as transparent electrode films and transparent plates used for transparent touch panels and the like can be mentioned. The transparent touch panel is, for example, a PDA such as an electronic notebook or a portable information terminal (device), or a car navigation system, a POS (point of sale information management) terminal, a portable order input terminal, an ATM (combined automatic deposit payment). Machine), facsimile, fixed telephone terminal, mobile phone, digital camera, video camera, personal computer, display for personal computer, television receiver, monitor display for television, ticket vending machine, measuring instrument, calculator, electronic instrument such as electronic musical instrument, copying It is used for office machines such as machines and ECRs (cash register machines), or for home appliances such as washing machines and microwave ovens. In addition, various uses of the antistatic article of the present invention include various optical elements. The optical element can prevent deterioration of optical performance due to electrostatic charge of dust.

[0051]

The present invention will be described in more detail with reference to the following examples.

Example 1 A transparent conductive layer 3 and a transparent adhesive layer 4 were formed in this order as a transfer layer 2 on one surface of a support sheet 1 made of a transparent biaxially stretched polyethylene terephthalate film having a thickness of 38 μm. Thus, an antistatic transfer foil 10 having a structure as shown in the sectional view of FIG. In addition,
The transparent conductive layer 3 is a needle-shaped tin oxide powder (made by Ishihara Sangyo Co., Ltd., trade name “FSS-10M”, long axis diameter 0) in which acrylic resin is used as a resin binder and antimony is doped as transparent conductive powder. 2 to 2.0 μm, minor axis diameter 0.01 to 0.02 μm) is 50 with respect to the resin component.
A coating liquid added by mass% was used to form a film having a thickness of 1.5 μm by a gravure reverse coating method. In addition, the transparent adhesive layer 4
Was formed to a thickness of 2 μm by a gravure reverse coating method using acrylic resin.

Further, by using the above-mentioned antistatic transfer foil, the transfer layer is thermally transferred onto one surface of the base material 6 made of a transparent acrylic resin plate having a thickness of 1 mm by the roll transfer method, and the cross-sectional view of FIG. An antistatic article 20 having the above structure was produced. For the transfer, a rubber roller having a surface of an iron core covered with silicone rubber was used as a transfer roller, and the surface temperature of the roller was 23.
It was carried out under the conditions of 0 ° C. and a pressure of 0.25 Pa (about 2.5 kgf / cm ² ).

Comparative Example 1 In Example 1, the transparent conductive powder was the same (antimony-doped) tin oxide powder, but had a spherical particle shape (manufactured by Mitsubishi Materials Corporation, trade name “T- 1 ", average particle size 0.02μ
An antistatic transfer foil was prepared in the same manner as in Example 1 except that the coating liquid was changed to m) and the addition amount was increased from 50% by mass to 60% by mass. Then, in the same manner as in Example 1, an antistatic transfer article was produced by transferring to an acrylic resin plate, and the performance was evaluated.

[Comparative Example 2] In Example 1, except that the transparent conductive layer was formed as a layer in which the addition of the transparent conductive powder was omitted in the formation of the transparent conductive layer (simple transparent resin layer).
A transfer foil was prepared in the same manner as in. Then, in the same manner as in Example 1, a transfer article was produced by transferring to an acrylic resin plate, and the performance was evaluated.

Comparative Example 3 An acrylic resin plate was spray-coated with a transparent paint made of a simple acrylic resin to which transparent conductive powder was not added.

[Performance Evaluation] For the processed articles such as the antistatic articles obtained in the above Examples and Comparative Examples, the surface resistivity (JI
S C 2141), the total light transmittance in the visible light region was evaluated by measuring 5 points of the article. As a result, in Example 1, the surface resistivity was 10 ⁶ to 10 ⁸ Ω / □, and good antistatic performance was obtained. Moreover, the total light transmittance is 91.
The transparency was good at 2%. On the other hand, Comparative Example 1 using the spherical tin oxide powder has a surface resistivity of 10 ⁷ to 10 ⁸ Ω /
□ and the antistatic performance is reduced, and the total light transmittance is 8
The value was 9.0%, which was lower than that in Example 1. As a reference example, Comparative Example 2 in which the transparent conductive powder was not added had a surface resistivity of 1
The total light transmittance was 0 ¹³ Ω / □ or more and 92.0%.
On the other hand, in Comparative Example 3 in which antistatic treatment was performed by coating, the surface of the article had a rough surface and the transparency was impaired.

[0058]

EFFECTS OF THE INVENTION (1) According to the antistatic transfer foil of the present invention, even with the same tin oxide powder, a larger amount of conductivity can be obtained by adding a small amount as compared with the case where the powder shape is spherical, and as a result, it is transparent. It is possible to impart superior antistatic performance to the property. Moreover, since the surface of the transferred article can be made a smooth surface such as a mirror surface as compared with the case where the surface is protected from static electricity by painting, the image seen by transmission or reflection does not become distorted due to surface irregularities like a painted surface. Therefore, for example, when applied to a window material of a display unit such as a display, the visibility of the display is not impaired.

(2) Further, in the structure having a transparent adhesive layer as the transfer layer, even if the material of the transparent conductive layer as the transfer layer is difficult to adhere to the article to be transferred, the transparent adhesive layer is used. Can be easily attached and transferred. Also,
The transfer layer can be freely transferred to the surface of the transfer target without applying an adhesive to the transfer target side or using an adhesive thermoplastic resin as a component of the transparent conductive layer of the transfer layer. Therefore, the flexibility of material selection for the transfer layer and the range of application of the article can be expanded.

(3) If the transfer layer also has a transparent resin layer in contact with the support sheet, the transparent resin layer may be a release layer, a hard coat layer, an uneven pattern layer, or a combination of two or more of these layers. It can be used as a layer or the like, and only one transparent conductive layer does not have to exhibit these properties, and various physical properties such as transferability and surface strength can be easily obtained in a well-balanced manner.

[Brief description of drawings]

FIG. 1 is a cross-sectional view illustrating an antistatic transfer foil of the present invention with respect to its four forms.

FIG. 2 is a cross-sectional view illustrating an antistatic article obtained by the antistatic transfer foil of the present invention.

FIG. 3 is a sectional view illustrating an antistatic article obtained by the antistatic transfer foil of the present invention.

[Explanation of symbols]

1 support sheet 2 Transfer layer 3 Transparent conductive layer 4 Transparent adhesive layer 5 Transparent resin layer 6 Base material (transfer target) 10 Antistatic transfer foil 20 Antistatic articles

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 2H086 CA12 CA16 CA21                 4F100 AA28B AB33 AK01D AK25G                       AK42 AR00B AT00A BA02                       BA03 BA07 BA10A BA10C                       CB00C DE10B EC04 GB41                       JG01B JG03 JN01B JN01C                       JN01D

Claims (3)

[Claims] 1. An antistatic transfer foil comprising at least a transparent conductive layer laminated as a transparent transfer layer on a support sheet, wherein the transparent conductive layer is a transparent conductive powder composed of needle-shaped tin oxide powder. A layer formed by being dispersed in a resin binder,
Antistatic transfer foil. 2. The antistatic transfer foil according to claim 1, wherein a transparent adhesive layer is further laminated on the transparent conductive layer as a transfer layer. 3. The antistatic transfer foil according to claim 1, which has a transparent resin layer as a transfer layer so as to be in contact with the support sheet.