JP5039850B1 - Method for producing functional resin laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transfer material capable of directly transferring a desired functional layer itself to a desired location, a method for producing a functional laminate using the transfer material, and a functional laminate obtained by the production method To do.
A functional transfer film in which a release layer, a functional layer, and a support layer are laminated in this order on the surface of a base film, wherein the functional layer is a single layer or a plurality of layers. And the release layer was formed by adding a silicone leveling agent to an ultraviolet curable urethane acrylate resin.
[Selection figure] None

Description

  The present invention relates to a functional transfer film for transferring a specific function to a film-like or plate-like resin laminate, a method for producing a functional resin laminate using the same, and a functional resin laminate, Specifically, for example, a specific function called transparent conductivity realized by ITO or the like is transferred to the surface of a film-like resin laminate (hereinafter also simply referred to as “film”) to obtain a transparent conductive film. The present invention relates to a functional transfer film capable of the method, a method for producing a functional resin laminate using the functional transfer film, and a functional resin laminate.

  The demand for a transparent conductive film that is transparent and has excellent conductivity as an electrode for liquid crystal display devices and touch panel applications that have been spreading explosively recently has increased dramatically.

  On the other hand, conventionally, for example, a transparent conductive layer is directly laminated on the surface of a base material to which conductivity is desired, or a transparent conductive layer is laminated on the surface of a transparent plastic film. For example, a conductive film has been attached.

  However, laminating a transparent conductive layer at a desired location by such a method requires the operation of laminating each sheet one by one, so that there is a limit in improving workability, and further, productivity and yield are increased. Was not improved, resulting in higher processing costs.

  Therefore, it has been considered to use a transfer method as a method of laminating the transparent conductive layer on the surface of the base material desired to be laminated.

  For example, in the conventional transparent conductive transfer material disclosed in Patent Document 1, a transparent conductive layer is conventionally laminated directly on the surface of a desired base material. It is proposed to laminate.

Patent registration No. 3794167

  Incidentally, ITO (tin-indium oxide) is one of materials widely used as the transparent conductive layer, and in Patent Document 1, ITO is also used. And in patent document 1, it is supposed that the laminated body which laminated | stacked ITO easily will be obtained by transferring ITO to the location which wants to laminate | stack this ITO.

  However, if the transfer material described in Patent Document 1 is actually used, for example, if the transfer material is to be transferred to the surface of the glass substrate, the transfer material is not transferred during transfer so that the ITO layer after transfer is not easily peeled off during transfer. However, it is necessary to transfer by applying high temperature and high pressure, but ITO frequently “cracks” because of that.

  That is, problems such as the occurrence of cracks in the ITO layer, resulting in failure to obtain desired conductivity, and poor appearance due to the occurrence of cracks have occurred.

  Therefore, in order to solve this problem, a situation has arisen in which it is necessary to provide some cushion layer instead of directly laminating only the ITO layer.

  However, in the field as described above, since lighter, thinner and smaller devices are being further promoted, it is desired to stack an ITO layer alone without providing an extra layer. Furthermore, there has been a problem that it becomes difficult to maintain transparency by providing an extra layer.

  However, even if ITO is laminated by transfer alone, the exposed ITO layer is exposed to high temperature and high pressure during transfer, and as a result, the ITO layer easily breaks, which is also a problem.

  Therefore, the present invention has been made in view of such problems, and the purpose thereof is a transfer material that can directly transfer a desired functional layer itself to a desired location, and a functional laminate using the transfer material. It is providing the manufacturing method of a body, and the functional laminated body obtained by this manufacturing method.

In order to solve the above-mentioned problem, the invention according to claim 1 of the present invention comprises a release layer formed by adding a silicone leveling agent to an ultraviolet curable urethane acrylate resin on the surface of a base film. In the functional transfer film formed by laminating a functional layer composed of a single layer or a plurality of layers and a support layer in this order, the function is formed on the surface of the support layer where nothing is laminated. A material adhering step for adhering a fluidized solution obtained by melting a resin, which is a raw material that is a material of an adherend to be laminated with a functional layer of a transferable film, in a solvent; and Solvent evaporation step formed by heating the functional transfer film in an attached state to evaporate the solvent and molding an adherend with the functional transfer film adhered thereto, and the function on the surface Sex transcription Irumu is formed by releasing the base film from the adherend adhered state, to become comprises a releasing step, and characterized.

The invention according to claim 2 of the present invention comprises a release layer formed by adding a silicone leveling agent to an ultraviolet curable urethane acrylate resin on the surface of a base film, and a single layer or a plurality of layers. A functional transfer film formed by laminating a functional layer and a support layer in this order, using a resin as a raw material as a material for an adherend to be laminated with the functional layer as a solvent. was to have a fluidity made by melting solution surface is deposited by pouring onto a casting drum or stainless steel smooth belt was made blunt, and the resin solution deposition step, the surface of the solution described above attached, the functional A sticking step of sticking the functional transfer film so that a surface of the transfer film on which the support layer is not laminated is in contact, and the functionality with the solution attached The solvent is evaporated by heating the transfer film, and the adherend in a state where the functional transfer film is adhered is molded, and the functional transfer film is adhered to the surface. And a mold release step in which the substrate film is released from the adherend in a state of being removed.

Invention of Claim 3 of this invention is the manufacturing method of the functional resin laminated body of Claim 2, After performing the said resin solution adhesion process, before performing the said sticking process, in the manufacturing method of the functional resin laminated body, the said adhesion It is characterized by performing an adhesive layer laminating step for pouring and adhering a resin as an adhesive layer onto the surface of the solution.

Invention of Claim 4 of this invention is the manufacturing method of the functional resin laminated body of any one of Claim 1 thru | or 3. WHEREIN: The said functional layer which comprises the said functional transfer film is the manufacturing method of the functional resin laminate. It is characterized by comprising a single layer of ITO layer.

Invention of Claim 5 of this-application invention is a manufacturing method of the functional resin laminated body of any one of Claim 1 thru | or 3. WHEREIN: The said functional layer which comprises the said functional transfer film is the said manufacturing method. It is characterized by comprising two layers of an ITO layer and an optical adjustment layer.

  If it is a functional transfer film concerning this invention, since it uses what added the silicone type leveling agent to the ultraviolet curable urethane acrylate resin as a mold release layer, it transfers without applying excessive high heat and high pressure at the time of transfer Can perform work. As a result, even if the functional layer of the functional transfer film is a material that is very brittle to high heat and pressure, such as ITO, it can be directly transferred to a desired location. If the functional transfer film according to the present invention is used at the time of production, so-called in-line transfer can be performed, and as a result, it is possible to easily impart functionality simultaneously with film production by the film support method.

  And, if the method for producing a functional resin laminate using the functional transfer film according to the present invention is used, since it is not necessary to expose the functional layer to high heat and high pressure, workability becomes very good, The production method with good productivity and yield can be made, and the productivity of the functional resin laminate obtained by such production method is also good. The adherend selected at this time is not limited to a film, and it is also effective to use it for a plate-like resin laminate such as an acrylic board.

  Embodiments of the present invention will be described below. Note that the embodiment shown here is merely an example, and is not necessarily limited to this embodiment. Moreover, although the film is mentioned as an example of what is referred to as a resin laminate in the present specification, the present invention is not limited to this, and a plate-like material such as an acrylic board is one type of resin laminate. It will be described as a thing.

(Embodiment 1)
A functional transfer film according to the present invention (hereinafter also simply referred to as “transfer film”) will be described as a first embodiment.

  The transfer film according to the present embodiment has a configuration in which a release layer, a functional layer, and a support layer are laminated in this order on the surface of a base film. The functional layer may be one type of layer, i.e., a single layer, or two or more types of layers, i.e., a plurality of layers.

  Further, the release layer is provided so that the functional layer can be exfoliated beautifully from the base film when performing an operation of transferring the functional layer to a desired location using a transfer film as will be described later. . Theoretically, when the base film and the functional layer have ideal mutual adhesion, it may not always be necessary, but in this embodiment, a release layer is provided. The release layer can be made of any material as long as it can achieve the above-mentioned purpose, but in the present embodiment, an ultraviolet curable urethane acrylate resin added with a silicone leveling agent is used. To do. This will be described later.

Hereinafter, the description will be made in order.
First of all, it is a base film, and this may be a resin film that is conventionally used in a transfer film. For example, a polyethylene terephthalate (PET) film, a polycarbonate (PC) film, a polyethylene naphthalate (PEN) film, an acrylic film, A synthetic resin film such as a polypropylene film, a polystyrene film, a polyamide film, a polyamideimide film, a polyethylene film, and a polyvinyl chloride film, a cellulose-based film, or a composite film thereof can be considered.

  In this embodiment, a PET film is used. The thickness of the PET film used here may be a thickness that has been widely used as a conventional transfer film, and specifically, it may be 25 μm or more and 200 μm or less.

A release layer is laminated on the surface of the base film. This release layer will be described.
Generally, a melamine resin or the like is used as a release layer in a transfer film, but a silicone leveling agent is added to an ultraviolet curable urethane acrylate resin as a release layer in a transfer film according to this embodiment. We will use what we did. The reason for this is when the transfer film according to the present embodiment is used in a method as described later, if a release layer is formed by adding a silicone leveling agent to an ultraviolet curable urethane acrylate resin, and This is because when the functional layer of the transfer film is an ITO layer, it is an optimal raw material in order to stably peel the ITO layer, that is, for example, to peel so as not to cause cracking at the time of peeling failure or peeling.

  Further, in the transfer film in the present embodiment, it is preferable that the release layer has a small surface energy and does not adversely affect the degree of vacuum at the time of sputtering for manufacturing the transfer film as described later. Yes, after transferring the ITO layer by the method described later, it does not contaminate the ITO surface, and after transferring the ITO layer, the surface of the ITO layer can be made as flat as possible. A release layer that can be used is very suitable. In this embodiment, a material in which a silicone leveling agent is added to an ultraviolet curable urethane acrylate resin is used as a material that easily realizes the state.

  Here, the silicone-based leveling agent is preferably 0.01 to 10.0%, more preferably 0.1 to 1.0% in terms of the solid content ratio to the ultraviolet (UV) curable urethane acrylate resin. I will add that.

  As a method for laminating the release layer, a method conventionally known as a wet coating method, such as a bar coating method, a casting method, a roller coating method, a spray coating method, an air knife coating method, a spin coating method, a flow coating method, or a curtain coating method. However, there is no particular limitation as long as the direct gravure method, the kiss gravure reverse method, the slit reverse method, etc., the bar coat method is used here.

  The thickness of the release layer is preferably 0.5 μm or more and 10.0 μm or less, and more preferably 1.0 μm or more and 5.0 μm or less.

  The UV curable urethane acrylate resin containing a silicone leveling agent laminated by the wet coating method is cured by irradiating active energy rays, that is, ultraviolet rays, after applying a certain temperature to volatilize the solvent. The

Next, the functional layer will be described.
This functional layer means a transparent and conductive layer such as ITO, for example, a conductive layer, a layer for preventing light reflection, and other various purposes. Although it is a layer having a function for achieving this, in this embodiment mode, it is a layer having transparent conductivity, and specifically, an ITO layer.

  More specifically, the ITO of the ITO layer in the transfer film according to the present embodiment is crystalline ITO or non-crystalline ITO, and the film thickness is 100 mm to 2000 mm, preferably 100 mm to 500 mm. And If the thickness exceeds 2000 mm, the substrate is likely to curl after film formation, the transmittance is reduced, or defects such as cracks are likely to occur in the ITO film itself.

The functional layer made of ITO is laminated as follows.
In this embodiment, an ITO film is formed on the surface of the resin film by sputtering using an ITO target. In this way, a relatively low resistance ITO layer can be provided.

  Alternatively, by using an ITO target, a film is formed by sputtering in an oxygen atmosphere to form an amorphous ITO film on the surface of the resin film, and then a heat treatment is performed to obtain a crystallized ITO film. It is also conceivable to provide an ITO layer that is relatively excellent in durability. The resistance value can be increased or decreased by adjusting the thickness of the ITO layer. However, the method may be well known and will not be described in detail here.

  The outline of the ITO layer laminating method is as described above. However, it should be noted that the ITO layer is laminated in consideration of the characteristics required in accordance with the actual use situation.

  In addition, the description has been made assuming that an ITO layer is laminated on the entire surface. However, for example, using a well-known technique such as masking, the ITO is applied only to a necessary portion, for example, a portion constituting a circuit. Laminating layers is also conceivable. By doing in this way, it is considered that the transparent conductive circuit is automatically completed when the transfer operation described later is completed.

Next, the support layer will be described.
As the support layer, a suitable resin film may be selected as needed, and a PET film is used in the present embodiment.

  This support layer only needs to have “strength of film” enough to support the ITO layer when the ITO layer, which is a functional layer, is finally transferred to a desired location. It is sufficient if it has sufficient interlaminar adhesion. And when this ITO layer is transferred to a desired location, this support layer is located on the side of the support layer where the ITO layer is not laminated, that is, on the outermost surface side of the transfer film according to the present embodiment.

  The transfer film according to the present embodiment has the configuration as described above, that is, has a configuration of PET film / release layer / ITO layer / support layer. Incidentally, here, the thickness of the PET film is 50 μm, the thickness of the release layer is 2.0 μm, the thickness of the ITO layer is 100 mm, and the thickness of the support layer is 1.0 μm.

Next, the actual usage method of this transfer film will be described.
If necessary, this transfer film has a specific function on the surface of a film-like or plate-like resin laminate, for example, by transferring an ITO layer having conductivity to the resin laminate by transferring it to the transparent laminate. It is used to impart sexual function. And it aims at providing an ITO layer directly on the surface of a desired location, without providing the functional layer made into the objective, for example, layers other than ITO layer as much as possible. Hereinafter, the description will be continued by taking the transfer of the ITO layer as an example.

  As described above, in general, when directly applied to the ITO layer, when it is pressurized at a conventionally known level, it is easy to generate a crack, and similarly, the ITO layer is easily damaged even when heated. The problem has arisen conventionally. In the case of further heating, if the object to be transferred, i.e., the adherend is a resin such as a PET film, the adherend itself is altered or damaged by heating, which has been a problem in the past.

  If the transfer film according to the present embodiment is to be used using a conventional transfer method for a resin laminate such as a resin film or a resin base material in a state where the manufacture is completed as in the past, this transfer film Since no layer is provided for protecting the ITO layer from heating or pressurization, cracks due to heating or pressurization are caused in the ITO layer or damage or the like occurs.

  By the way, there is a solution casting method (hereinafter also referred to as “casting method”) as one method for producing a resin laminate such as a resin film or a resin base material. This is a production method in which physical pressure is not applied to a film or the like, and therefore, the polymer is not oriented, and the directionality does not occur in strength, optical characteristics, and the like. And this manufacturing method also has the characteristic that there is little heating amount compared with the melt extrusion molding method, for example.

  Therefore, the transfer film according to the present embodiment is transferred to the surface of a resin laminate such as a desired resin film or resin substrate without heating or pressurizing so as not to cause cracks or breakage in the ITO layer. If it exists, when manufacturing resin laminated bodies, such as a resin film and a resin base material, by the said casting method, it will be suitable if the transfer film concerning this Embodiment is used.

  Therefore, hereinafter, a manufacturing method for obtaining a resin film, a resin base material, and the like to which functionality is imparted using the transfer film according to the present embodiment will be described. In the following description, film production is continued with the manufacture in mind. However, the present invention is not necessarily limited to film, and it should be noted in advance that it can be similarly applied to a film that can be manufactured by a casting method.

  Materials for the adherend include acrylic resin, polycarbonate, cyclic olefin resin, other olefin resins (polyethylene, polypropylene, etc.), polyarylate, polysulfone, polyethersulfone, polynorbornene, polyethylene terephthalate (PET), polyethylene. Naphthalate, triacetyl cellulose, or the like, or a composite film-like material thereof may be considered, and other materials may be used. However, in the following description, the description is continued with the PET film in mind.

  Basically, a film manufacturing method by a conventionally known casting method is executed. (Hereafter, explanation will be continued by taking film production as an example.)

  First, an adherend to be obtained, here, a material of a resin film (acrylic film) is melted in a solvent to obtain a fluidized solution. Next, this is poured onto a casting drum having a smooth surface or a smooth belt made of stainless steel to be adhered. And this is heated, a solvent is evaporated, and a film is finally shape | molded.

  This is a basic technique of the casting method, but in this embodiment, the above-described transfer film is used instead of the casting drum or the smooth belt.

  Specifically, the transfer film is set so that the solution is poured into the surface of the support layer of the transfer film where nothing is laminated, and the above-described casting method is executed. And if a film is shape | molded, after that, the PET film which is a base film of a transfer film will be peeled finally. In addition, a peeling layer is peeled together with this peeling. And a functional resin film is obtained.

  A different method is also conceivable. That is, after performing the casting method as described above and pouring the solution, before heating, the transfer film is pasted so that the surface of the support layer of the transfer film that is not laminated is in contact with the poured solution. It is the method of putting on and performing the shaping | molding of a film after that. Also in this case, after the molding of the film is completed, the functional resin film can be obtained by peeling off the PET film that is the base film of the transfer film.

  In addition, an adhesive layer may be interposed if necessary to adhere the transfer film and the resin film obtained by executing the casting method using a solution. This adhesive layer is a UV curable resin. Etc. can be used. In order to interpose this adhesive layer, after the solution is poured, before the transfer film is attached, an adhesive layer laminating step for pouring and adhering a resin as the adhesive layer to the surface of the solution may be executed. . It should be noted that when UV curable resin is used for the adhesive layer, UV irradiation is required before releasing.

  And when peeling PET film which is a base film from this transfer film, peeling is very beautiful by using a release layer to which a silicone leveling agent is added to a UV curable urethane acrylate resin as described above. It can be executed.

  By using such a manufacturing method, when the ITO layer is transferred, only heating at the time of film formation is applied, and no pressure is applied. The heating temperature at the time of film formation is usually about several tens of degrees Celsius to 150 degrees Celsius. However, if the temperature is within this range, the ITO layer is not broken. In other words, high-temperature heating and pressurization are not substantially applied to the transfer film and the ITO layer in the process of the above manufacturing method, and as a result, it is equivalent to the case where the ITO layer is transferred to a desired location very simply This product can be easily obtained.

  In addition, by using such a manufacturing method, as described above, if the ITO layer is laminated in advance only on the ITO layer in the circuit diagram in advance, that is, if it is a pre-patterned ITO layer, the PET layer is finally obtained. If the film is peeled off, a functional film having a transparent conductive circuit can be obtained as it is, so that there is no need for further work such as etching, and a transparent conductive film can be obtained very simply.

(Embodiment 2)
Next, a transfer film having a configuration in which the functional layer portion in the first embodiment is different will be described as a second embodiment.

  The transfer film according to the first embodiment has a configuration of base film / release layer / functional layer / support layer, and the functional layer is a single layer. The second embodiment Then, it is assumed that there are a plurality of functional layers.

  For example, in the first embodiment, the functional layer is a single ITO layer, but in this embodiment, an optical adjustment layer for further optical adjustment is adjacent to the ITO layer, and these are combined. It is called a functional layer. Thus, compared with the case where the functional layer is a single layer, a layer for reinforcing the functional layer, a layer for storage, and other layers in order to achieve other purposes, one layer or two or more layers It is conceivable to stack them adjacent to each other.

  The transfer film according to the second embodiment is assumed to have such a configuration, and in the following description, further description will be continued on the assumption that the transfer film is composed of two layers of an ITO layer and an optical adjustment layer.

  As described above, using the transfer film of the present invention, for example, when an ITO layer is laminated on the surface of the PMMA film, it can certainly be a transparent conductive film, but actually after the ITO layer is laminated, By etching the ITO layer into a circuit, there is a problem that a color difference occurs between the ITO layer laminated portion and the etched portion, and the visibility and light transmittance are reduced. May occur.

The color difference between the etched portion and the etched portion will be further described.
In the circuit formation portion, a so-called color difference occurs between the laminated portion of the ITO film and the portion where the ITO film is not laminated. In addition, the appearance of the ITO layer, which is originally desired to be uniformly transparent, appears, and the laminated portion of the ITO film constituting the circuit can be visually recognized with a certain degree of outline. In other words, a phenomenon that can be said to be a visibility impediment such that the circuit part appears to float up at first glance occurs, which is a problem.

  Therefore, in order to cope with these problems, in the case of a normal transparent conductive film, after laminating an ITO layer, an optical adjustment layer is laminated on the surface. By laminating the optical adjustment layer, after etching a part of the ITO layer, the removed portion, which is a portion where the ITO layer is removed by etching, and the ITO layer remains even after the etching. Residual portions that are locations, transmission color difference (values according to a specific formula using L * value, a * value, b * value) and reflection color difference (L * value, a * value, b * value) at each location Can be reduced as much as possible, and a substantially uniform transparent appearance can be obtained.

  In addition, if the idea of the transfer film according to the present invention is used, if the optical adjustment layer is previously laminated on the ITO layer, the optical adjustment layer is separately laminated after the ITO layer lamination by transferring them all at once. Thus, the number of manufacturing steps as a whole can be reduced, and as a result, work efficiency can be improved and costs can be reduced.

This optical adjustment layer will be briefly described.
For example, when a low refractive index layer and a high refractive index layer are laminated on the surface of the ITO layer, the low refractive index layer and the high refractive index layer exhibit a function called a so-called optical adjustment layer. The low refractive index layer has a light refractive index n of about 1.4 to 1.6. The high refractive index layer has a light refractive index n of about 1.6 to 2.0.

  By laminating such an optical adjustment layer, even if only the ITO layer has a yellowish appearance due to the reflection of incident light, the incident light is incident by the optical adjustment layer. By manipulating the corners, it becomes possible to maintain transparency by adjusting the reflected light.

  In order to achieve such effects, the optical adjustment layer is usually laminated on the surface of the ITO layer. However, if the optical adjustment layer is provided on the transfer film in advance as in this embodiment, Since the work can be completed at once, a suitable transfer film can be obtained.

  With the functional transfer film described above, it is possible to transfer a desired functional layer without requiring high-temperature heating, pressurization, etc., and therefore, the functional transfer film is produced by a casting method. By using it during the casting process of the film to be transferred, the functional layer can be transferred to the desired film surface without heating and pressurizing at high temperature. If it is used for transferring a functional layer, it is much simpler than before and there is no need to laminate a cushion layer or the like for protecting the ITO layer that has been conventionally required. Can be stacked by direct transfer, so that the stacking operation can be performed very simply and the workability is improved.

Claims (5)

A release layer formed by adding a silicone leveling agent to an ultraviolet curable urethane acrylate resin on the surface of the base film, a functional layer composed of a single layer or a plurality of layers, a support layer, In the functional transfer film obtained by laminating the layers in this order, on the surface of the support layer where nothing is laminated,
A material adhering step for adhering a fluidized solution obtained by melting a resin, which is a raw material that is a material of an adherend to be laminated, on the functional layer of the functional transfer film;
A solvent evaporation step, in which the functional transfer film with the solution attached is heated to evaporate the solvent, and the adherend with the functional transfer film attached is molded,
A mold release step in which the base film is released from an adherend in a state where the functional transfer film is adhered to the surface;
Comprising
A method for producing a functional resin laminate. A release layer formed by adding a silicone leveling agent to an ultraviolet curable urethane acrylate resin on the surface of the base film, a functional layer composed of a single layer or a plurality of layers, a support layer, Of the functional transfer film in which the functional layers are laminated in this order, a fluidized solution obtained by melting a resin, which is a raw material that is a material of an adherend to be laminated with the functional layer, in a solvent. , A resin solution adhesion step of pouring and adhering onto a smoothing belt made of a casting drum or stainless steel with a smooth surface;
The surface of the solution described above attached, of the functional transfer film, nothing like the surface of the laminated non side is in contact of the support layer, and the affixing step for attaching the functional transfer film,
A solvent evaporation step, in which the functional transfer film with the solution attached is heated to evaporate the solvent, and the adherend with the functional transfer film attached is molded,
A mold release step in which the base film is released from an adherend in a state where the functional transfer film is adhered to the surface;
Comprising
A method for producing a functional resin laminate.
In the manufacturing method of the functional resin laminated body of Claim 2,
After executing the resin solution adhesion step, before executing the sticking step,
Performing an adhesive layer laminating step for pouring and adhering a resin as an adhesive layer onto the surface of the adhered solution;
A method for producing a functional resin laminate. In the manufacturing method of the functional resin laminated body of any one of Claim 1 thru | or 3,
The functional layer constituting the functional transfer film is composed of a single ITO layer;
A method for producing a functional resin laminate. The method for producing a functional resin laminate according to any one of claims 1 to 3, wherein the functional layer constituting the functional transfer film is an ITO layer and an optical adjustment layer. Consisting of layers,
A method for producing a functional resin laminate.