JP6086899B2 - Energy ray-curable hydrophilic pressure-sensitive adhesive composition, pressure-sensitive adhesive sheet, and hydrophilic structure - Google Patents

Description

  The present invention relates to an energy beam curable hydrophilic pressure-sensitive adhesive composition and a pressure-sensitive adhesive sheet, and more specifically, an energy beam curable hydrophilic pressure-sensitive adhesive composition suitable for three-dimensional stretching that is three-dimensionally stretched and a structure composed thereof. The present invention relates to a pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer and a hydrophilic structure obtained from the pressure-sensitive adhesive composition and the pressure-sensitive adhesive layer.

  Attention has been focused on a method of miniaturizing and modularizing an entire system for performing chemical analysis, chemical synthesis, or bio-related analysis using microfabrication technology. Such a module is called a μTAS (Micro Total Analysis System) or a microreactor. This microreactor has the advantage that the efficiency of heating and cooling is high because the amount of the target substance to be analyzed or synthesized is small, and the reaction speed is high because the diffusion length of the target substance is short. Further, since the entire system is miniaturized, there is an advantage that time required for analysis is shortened and rapid evaluation is possible. Furthermore, even when it is necessary to discard the equipment used for analysis or reaction, there is an advantage that the total cost required for disposal can be suppressed because the entire used module may be discarded.

Because of such advantages, a number of techniques relating to microreactors have been proposed.
For example, Patent Document 1 has three or more merging units composed of two or more inflow passages, a merging portion where they merge, and one outflow passage extending in the downstream direction from the merging portion. It is a minute merge channel structure, in which one merge unit is disposed on the most downstream side, and its outflow path is an outlet of the minute merge channel structure, and the remaining merge unit outflow paths are located further downstream. There is disclosed a minute merge channel structure characterized in that it is an inflow channel of a merge unit, and the remaining inflow channel is an inlet of the minute merge channel structure.

  Patent Document 2 discloses a plurality of reaction vessels arranged on the same plane, and each reaction vessel connected to each reaction vessel through a fine channel, and a reaction solution provided on the plane on which the plurality of reaction vessels are arranged. A biological sample reaction chip is disclosed that includes an introduction channel and a reaction solution movement stop unit that is connected to a terminal portion of the reaction solution introduction channel and that can control the movement of the reaction solution.

  Patent Document 3 discloses a micro flow channel for supplying a liquid to a sensor or discharging a liquid supplied to the sensor, and the flow channel body used in an upright state has a divided surface parallel to the flow channel center line. The first wall surface portion that exhibits hydrophobicity and the second wall surface portion that exhibits hydrophilicity are divided, and the flow path body has a condition represented by a specific expression using the shape of the flow path as a parameter. A microchannel characterized by filling is disclosed.

  As described above, many technologies related to the structure of the microreactor have been proposed. However, the structure of such a microreactor is premised on the application of the microfabrication technology that has been used in the manufacture of semiconductor devices. In many cases, a semiconductor material such as silicon or an inorganic material such as glass is used as the material. For example, the material of the microreactor disclosed in Patent Document 2 is glass.

  However, from the viewpoint of increasing productivity, attempts have been made to use resin-based materials as microreactor materials. For example, the microreactor disclosed in Patent Document 3 is made of plastic and glass. A resin material contains a resin component as one of the main components, and can enjoy the advantages of the resin material as a whole (especially the high ability to create shapes described later) to the same extent as the resin material. Say.

Responding to such attempts, proposals have been made on resin-based materials intended to be applied to microreactors.
For example, in Patent Document 4, as a material for forming a structure formed by molding a two-dimensional or three-dimensional microchannel or nanochannel on the surface, the first component is a polypropylene resin, A synthetic resin composition comprising two or more synthetic resin components, wherein the two components are hydrogenated derivatives of a block copolymer represented by the general formula XY, is disclosed.

  Patent Document 5 discloses a resin-filler composite material for a resin substrate for a microreactor, wherein the filler has an inorganic material or a polymer material having an aspect ratio of 10 or more, or a birefringence of a predetermined value or more. A material that contains 0.01 to 200 parts by weight of a filler with respect to 100 parts by weight of a resin is disclosed.

JP 2010-158650 A JP 2009-136220 A JP 2008-203003 A JP 2010-264446 A JP 2008-231427 A

  One of the advantages that resin-based materials as microreactor materials have over other materials (semiconductors such as silicon, inorganic materials such as glass, and metals) is compared to other materials. Therefore, shape creation is easy and the degree of freedom of shapes that can be created may be high. For example, if injection molding technology, blow molding technology or press molding technology is applied using a thermoplastic resin as a resin-based material, a concave shape with a high aspect ratio or a complicated step shape is generally used in the manufacture of semiconductor devices. Compared with the case of using the microfabrication technique used, it is possible to manufacture easily.

  However, the resin-based material has a problem that its surface is generally hydrophobic. Considering that in many cases the liquid flowing in the microreactor is an aqueous solution (almost all are aqueous solutions in the case of bio-related applications), the hydrophobicity of the microreactor disclosed in Patent Document 3 is positive. Unless there is a circumstance where the microreactor is used, at least the liquid contact surface is required to be hydrophilic.

  As such a hydrophilization technique, surface modification represented by corona treatment is exemplified. However, it is not easy to uniformly modify the liquid contact surface on the inner surface of the microreactor having a small and complicated structure.

  Another example of means for hydrophilizing the liquid contact surface of a microreactor made of a resin material is to contain a hydrophilicity imparting agent in the resin material. The most common such materials are surfactants and ionic liquids.

However, resin-based materials containing surfactants and ionic liquids essentially avoid the elution of ionic substances from the resin-based materials because the ionic substances physically move within the resin-based materials. I can't. Although measures can be taken to reduce the extent of elution, the fact of elution reduces the reliability of the analysis results and raises concerns about the impact on the organism in bio-related applications. Therefore, it is practically unacceptable to apply a means for changing the physical properties of the resin material using a surfactant or an ionic liquid to the microreactor.
Moreover, when an ionic liquid, such as an imidazolium salt, is included in the resin-based material, this ionic material contributes to hydrophilicity of the resin surface, but this material becomes an inhibitor of the plastic deformability of the resin-based material. As a result of studies by the present inventors, it has been found that the ability to create shapes, which is the greatest benefit of using a resin-based material, is reduced. In particular, when performing three-dimensional molding, which is a shape creation means for forming a predetermined shape by three-dimensionally extending a resin-based material containing an ionic liquid, the resin-based material can be expanded without breaking. The degree is significantly reduced.

  Therefore, the present invention includes a resin material suitable as a constituent material of a microstructure having a hydrophilic surface represented by a microreactor, specifically, a resin composition and a layer made of the resin composition. It is an object to provide a sheet.

  The present invention provided in order to solve the above-mentioned problems is, firstly, energy beam curing containing an energy beam curable resin and a particulate hydrophilicity imparting agent dispersed in the energy beam curable resin. Type hydrophilic pressure-sensitive adhesive composition, wherein the energy ray-curable hydrophilic pressure-sensitive adhesive composition has a breaking elongation of 2000% or more and a stress relaxation rate of 70% or more and 95% or less before energy ray curing. The energy ray-curable hydrophilic pressure-sensitive adhesive composition is used as a 20 μm-thick pressure-sensitive adhesive layer formed on a 38 μm-thick polyethylene terephthalate resin sheet, and the pressure-sensitive adhesive layer is energy-ray-cured to form a pressure-sensitive adhesive cured layer. The half-life of the charged voltage measured using a half-life measuring instrument defined in JIS L1094: 1997 is 60 seconds or less at 25 ° C. and 50% RH. Providing energy beam curable hydrophilic pressure sensitive adhesive composition (invention 1) to.

  Here, “hydrophilicity” in the energy ray-curable hydrophilic pressure-sensitive adhesive composition means that the surface of a cured product obtained by curing the pressure-sensitive adhesive composition with energy rays has hydrophilicity.

  Since the hydrophilicity-imparting agent is in the form of particles, the hydrophilicity-imparting agent is detached from the structure in use, and the hydrophilicity of the surface of the structure is lowered, or a substance that is in contact with the structure (for example, a reaction solution) ) Is suppressed. In addition, since the energy ray curable resin has a sufficiently high breaking elongation before curing, three-dimensional structures having various shapes can be obtained. By curing this three-dimensional structure with energy rays, a hydrophilic structure that can be suitably used as a microreactor or the like can be obtained.

  In the said invention (invention 1), it is preferable that the average particle diameter of the said particulate hydrophilicity imparting agent is 1000 nm or less (invention 2). When the average particle size is 1000 nm or less, the surface roughness of the hydrophilic three-dimensional structure obtained by energy ray curing is reduced, and excellent surface properties are easily obtained.

  In the said invention (invention 1 and 2), it is preferable that the said particulate hydrophilicity imparting agent consists of a metal oxide (invention 3). Since the particulate hydrophilicity imparting agent made of a metal oxide is excellent in optical properties, the possibility of occurrence of curing variation when the energy ray-curable hydrophilic pressure-sensitive adhesive composition is cured is reduced. Moreover, it becomes easy to observe the content (for example, reaction liquid) of the hydrophilic three-dimensional structure obtained by energy ray curing.

  In the above invention (Inventions 1 to 3), the metal oxide may contain one or more selected from the group consisting of phosphoric acid-doped tin oxide and a double oxide consisting of zinc oxide and antimony pentoxide. Preferred (Invention 4). These metal oxides are particularly excellent in optical properties.

  In the above invention (Invention 1 to 4), the total light transmittance before energy ray curing when the energy ray curable hydrophilic adhesive composition is a 5 μm thick adhesive layer is 80% or more, and It is preferable that the adhesive layer has a haze of 10% or less (Invention 5). By having such excellent optical properties, the possibility of variation in curing in the composition is particularly reduced, and it becomes easy to observe the contents of the cured hydrophilic three-dimensional structure. .

  In the said invention (invention 1-5), it is preferable that the said energy beam curable resin contains a (meth) acrylic acid ester copolymer and an energy beam curable urethane acrylate (invention 6). By containing such a material, it becomes easy for the composition before curing to satisfy the aforementioned mechanical properties.

  In the said invention (invention 6), it is preferable that content of the said energy-beam curable urethane acrylate is 50-200 mass parts with respect to 100 mass parts of said (meth) acrylic acid ester copolymers (invention 7). ). By having such a composition, the above composition can be sufficiently cured, and it becomes easy to maintain the shape when the composition is formed into a sheet shape or the like.

  In the said invention (invention 6 and 7), the glass transition temperature (Tg) before energy ray hardening of the said (meth) acrylic acid ester copolymer is -50-0 degreeC, The said energy ray hardening type urethane acrylate of The glass transition temperature (Tg) after energy beam curing is preferably -40 to 20 ° C (Invention 8). By having such a composition, the energy beam curable resin can achieve an appropriate balance between adhesive strength and breaking strength.

  In the said invention (invention 6 to 8), it is preferable that the pencil hardness after energy ray hardening of the said energy ray curing type urethane acrylate is B-5B (invention 9). By providing such mechanical properties, the shape of the hydrophilic three-dimensional structure can be favorably maintained, and the possibility that the obtained structure is brittlely broken can be reduced.

  The energy ray-curable hydrophilic pressure-sensitive adhesive composition of the above invention (Invention 1 to 9) is preferably used for three-dimensional molding (Invention 10). As described above, the energy beam curable hydrophilic pressure-sensitive adhesive composition according to the present invention is excellent in curability and mechanical properties before and after curing. Therefore, it is suitable as a material for performing three-dimensional molding.

  In the said invention 10, the said energy-beam curable hydrophilic adhesive composition may be three-dimensionally shaped by extending | stretching three-dimensionally (invention 11). Even if this composition is three-dimensionally stretched, it has excellent elongation at break before curing, so the composition is less likely to cohesively break in the process, and the stress relaxation rate before curing is within an appropriate range, so The shape is difficult to change in between.

  The present invention secondly provides a pressure-sensitive adhesive sheet comprising a pressure-sensitive adhesive layer composed of the energy ray-curable hydrophilic pressure-sensitive adhesive composition according to any one of the above inventions (Inventions 1 to 11). (Invention 12)

  This pressure-sensitive adhesive sheet is easy to maintain its shape because the composition according to any of the above inventions (inventions 1 to 11) is excellent in mechanical properties before being cured. When molded, problems such as cohesive failure are unlikely to occur. Furthermore, since this adhesive sheet has hydrophilicity, a hydrophilic three-dimensional structure can be obtained.

  Thirdly, the present invention provides a pressure-sensitive adhesive layer composed of the energy ray-curable hydrophilic pressure-sensitive adhesive composition according to any one of the above inventions (Inventions 1 to 11), and two sheets sandwiching the pressure-sensitive adhesive layer. A pressure-sensitive adhesive sheet comprising a release sheet is provided (Invention 13).

  Since this pressure-sensitive adhesive sheet can appropriately protect the pressure-sensitive adhesive layer composed of the composition according to any of the above inventions (inventions 1 to 11) until it is attached to the adherend, Possibility that the adhesiveness of the surface which makes the bonding surface falls or the surface is contaminated is reduced.

  Fourth, the present invention is that the energy ray-curable hydrophilic pressure-sensitive adhesive composition according to any one of the above inventions (Inventions 1 to 11) is three-dimensionally molded by three-dimensionally extending. A hydrophilic structure is provided (Invention 14).

  Since the energy ray-curable hydrophilic pressure-sensitive adhesive composition according to any one of the above inventions (Inventions 1 to 11) has excellent mechanical properties, various hydrophilic structures obtained by three-dimensional molding of such a composition are available. Can have various shapes.

  In addition, the present invention fifthly is characterized in that the pressure-sensitive adhesive layer in the pressure-sensitive adhesive sheet according to any of the above inventions (Inventions 12 and 13) is three-dimensionally molded by three-dimensionally extending. A hydrophilic structure is provided (Invention 15).

  Since the energy ray-curable hydrophilic pressure-sensitive adhesive composition constituting the pressure-sensitive adhesive layer in the pressure-sensitive adhesive sheet according to any of the above inventions (Inventions 12 and 13) has excellent mechanical properties, the composition is three-dimensionally molded. The resulting hydrophilic structure can have various shapes.

  The energy ray curable hydrophilic pressure-sensitive adhesive composition of the present invention has a particulate hydrophilicity imparting agent, and the surface of a structure (for example, a microreactor) obtained from the composition is made hydrophilic by the particulate hydrophilicity imparting agent. Turn into. By using such a particulate hydrophilicity-imparting agent, the hydrophilicity-imparting agent is detached from the structure in use, the hydrophilicity of the surface of the structure is reduced, or a substance (for example, a reaction solution) that comes into contact with the structure ) Is suppressed. In addition, because the elongation at break before energy beam curing is sufficiently high, complex shapes that are difficult to form by shape creation processing performed using general semiconductor-related fine processing technology, such as shapes with a large aspect ratio, are It can be easily formed by molding. A hydrophilic structure having high mechanical strength can be obtained by energy beam curing of the three-dimensional structure thus obtained, and such a structure can be suitably used as a microreactor or the like.

It is sectional drawing of an example of an adhesive sheet provided with the adhesion layer formed from the adhesive composition which concerns on embodiment of this invention. It is sectional drawing of another example of an adhesive sheet provided with the adhesion layer formed from the adhesive composition which concerns on embodiment of this invention. It is a figure which shows notionally an example of the process of obtaining the hydrophilic three-dimensional structure which has the shape of a microchannel by solid-molding the adhesive composition which concerns on embodiment of this invention. It is explanatory drawing which shows the procedure of the stretch moldability evaluation in Test Example 6. FIG. 10 is a cross-sectional view conceptually showing a cross-sectional view of an ion elution test cell for performing an ion elution test in Test Example 8.

Hereinafter, embodiments of the present invention will be described.
[Energy ray curable hydrophilic pressure-sensitive adhesive composition]
The energy beam curable hydrophilic pressure-sensitive adhesive composition according to the present embodiment (hereinafter sometimes simply referred to as “hydrophilic pressure-sensitive adhesive composition” or “pressure-sensitive adhesive composition”) The stress relaxation rate satisfies the following requirements, and these characteristics make it suitable for three-dimensional molding.

  Here, in this application, “three-dimensional molding” means a shape creation processing method that forms a predetermined shape by three-dimensionally extending a material to be processed, and the term “extension” includes the concept of expansion. Shall be included.

  The breaking elongation of the energy ray-curable hydrophilic pressure-sensitive adhesive composition according to this embodiment is 2000% or more. The elongation at break was measured by processing the hydrophilic pressure-sensitive adhesive composition into a single pressure-sensitive adhesive layer without a substrate or the like. Specifically, the thickness was 500 μm, the width was 15 mm, and the length was 55 mm. 25 mm), the hydrophilic pressure-sensitive adhesive composition is stretched at a speed of 200 mm / min in an environment of 23 ° C. and 50% RH.

  The stress relaxation rate of the energy ray-curable hydrophilic pressure-sensitive adhesive composition according to this embodiment is 70 to 95%, preferably 75 to 93%, and particularly preferably 80 to 91%. When the stress relaxation rate is 70% or more, the hydrophilic pressure-sensitive adhesive composition can be easily held in a stretched state, so that it can be easily molded into a target shape. Further, when the stress relaxation rate is 95% or less, the shape is further deformed by an external force (for example, gravity, etc.) other than the force for extending the hydrophilic pressure-sensitive adhesive composition while maintaining the fully extended state. Can be suppressed.

The stress relaxation rate refers to the ratio of the stress obtained by stretching the hydrophilic pressure-sensitive adhesive composition by 300% in the tensile test to the stress at the time of holding for 300 seconds. Specifically, the tensile conditions were as follows: a hydrophilic pressure-sensitive adhesive composition molded into a thickness of 500 μm, a width of 15 mm, and a length of 55 mm (of which the measurement range was 25 mm), in an environment of 23 ° C. and 50% RH, It shall be performed by stretching 300% at a speed of 200 mm / min. The stress relaxation rate is calculated by the following formula based on the stress A at 300% elongation and the stress B 300 seconds after the elongation stop.
Stress relaxation rate (%) = {(A−B) / A} × 100 (%)

  From the hydrophilic pressure-sensitive adhesive composition according to this embodiment, the surface of the cured product obtained by energy beam curing from the energy-beam curable hydrophilic pressure-sensitive adhesive composition according to the present embodiment has hydrophilicity. A 20 μm thick adhesive layer is formed on a 38 μm thick polyethylene terephthalate resin sheet, and the adhesive layer obtained by curing the adhesive layer with energy rays is half-life defined in JIS L1094: 1997. The half-life of the charged voltage measured using a measuring instrument (the time until the charged voltage is attenuated to 1/2 at 25 ° C. and 50% RH after being charged by corona discharge) is 60 seconds or less.

  When this half-life is 60 seconds or less, the surface of the pressure-sensitive adhesive cured layer has sufficient hydrophilicity, and the occurrence of problems due to insufficient hydrophilicity can be suppressed. A specific example of the above problem is that the liquid does not enter the concave portion of the microstructure, and at this time, the reaction that is scheduled to proceed in the concave portion does not proceed, and the liquid is in the concave portion that is the measurement unit. There may be a problem that it does not exist and cannot be analyzed. In addition, turbulent flow in the flow path and bubble entrainment may also be mentioned as an example of the above-mentioned problem.At this time, the flow rate management related to the reaction is insufficient, and the reaction does not proceed as planned. There may be a problem that the reliability of the measurement result is lowered due to the addition of bubble information during measurement.

  When the above half-life is 45 seconds or less, the surface of the pressure-sensitive adhesive cured layer has particularly excellent hydrophilicity, and it is possible to more stably avoid the above problems.

  In addition, as a hydrophilicity evaluation method, it is common to measure the contact angle of a droplet formed on a flat resin material to be evaluated, but the hydrophilic adhesive composition according to this embodiment Since the product contains a particulate hydrophilicity imparting agent, the surface of the pressure-sensitive adhesive cured layer may have irregularities depending on the shape (particle size, etc.) of the particulate hydrophilicity imparting agent. In this case, since the interface between the droplet and the resin-based material does not form a flat surface, the reliability is low even if the contact angle of the droplet is measured. Therefore, in this case, it is not appropriate to use the contact angle as a criterion for determining whether or not the surface of the pressure-sensitive adhesive cured layer has sufficient hydrophilicity. On the other hand, in the measurement of the half-life described above, since the measurement result is hardly influenced by the surface property of the pressure-sensitive adhesive cured layer, it is possible to stably and quantitatively evaluate the degree of hydrophilicity.

  The energy ray-curable hydrophilic pressure-sensitive adhesive composition according to this embodiment has a total light transmittance of 80% or more before energy ray curing as defined in JIS K7361-1: 1997 when the layer has a thickness of 5 μm. It is preferable that Moreover, it is preferable that the above-mentioned pressure-sensitive adhesive layer has a haze defined in JIS K7136: 2000 of 10% or less before energy ray curing. In the case of providing these optical characteristics, even when the structure is made into a three-dimensional shape by three-dimensional molding, it is stably realized that the energy rays irradiated to the entire structure reach. Therefore, by having these optical properties, local deterioration of the mechanical properties in the structure after curing is stably avoided.

  The energy ray-curable hydrophilic pressure-sensitive adhesive composition according to this embodiment comprises an energy ray-curable resin and a hydrophilic pressure-sensitive adhesive composition containing a particulate hydrophilicity imparting agent dispersed in the energy ray-curable resin. It is a thing. Hereinafter, the composition of the energy beam curable resin and the particulate hydrophilicity imparting agent will be described in detail.

[Energy ray curable resin]
The composition of the energy beam curable resin according to the present embodiment is arbitrary as long as the energy beam curable hydrophilic pressure-sensitive adhesive composition before curing satisfies the mechanical properties (breaking elongation and stress relaxation rate). The energy beam curable resin according to the present embodiment preferably contains (1) a (meth) acrylic acid ester copolymer and (2) an energy beam curable urethane acrylate, and (3) a photopolymerization initiator. Those further containing are particularly preferred. The energy beam curable resin according to this embodiment may contain (4) other components, for example, a crosslinking agent.

(1) (Meth) acrylic acid ester copolymer (Meth) acrylic acid ester copolymer is not particularly limited, and (meth) acrylic acid ester copolymer conventionally used as a resin component of an acrylic pressure-sensitive adhesive composition. Any polymer can be appropriately selected and used. As such a (meth) acrylic acid ester copolymer, for example, a (meth) acrylic acid alkyl ester having an alkyl group having 1 to 20 carbon atoms, a monomer having a functional group having active hydrogen, and, if desired, Preferred examples include copolymers with other monomers used. In addition, (meth) acrylic acid ester means both acrylic acid ester and methacrylic acid ester. The same applies to other similar terms.

  Examples of (meth) acrylic acid alkyl esters having 1 to 20 carbon atoms in the alkyl group include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, and butyl (meth). Acrylate, octyl (meth) acrylate, isobutyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, decyl (meth) Examples include acrylate, dodecyl (meth) acrylate, myristyl (meth) acrylate, palmityl (meth) acrylate, stearyl (meth) acrylate, and the like. These may be used individually by 1 type and may be used in combination of 2 or more type.

  On the other hand, examples of the monomer having a functional group having active hydrogen include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl ( Hydroxyalkyl (meth) acrylates such as (meth) acrylate, 3-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, monomethylaminoethyl (meth) acrylate, monoethylaminoethyl (meth) acrylate, monomethylaminopropyl Monoalkylaminoalkyl (meth) acrylates such as (meth) acrylate and monoethylaminopropyl (meth) acrylate; Ethylene such as acrylic acid, methacrylic acid, crotonic acid, maleic acid, itaconic acid, citraconic acid Such as sexual unsaturated carboxylic acid. These monomers may be used independently and may be used in combination of 2 or more type.

  Examples of other monomers used as desired include vinyl esters such as vinyl acetate and vinyl propionate; olefins such as ethylene, propylene and isobutylene; halogenated olefins such as vinyl chloride and vinylidene chloride; Styrene monomers such as styrene and α-methylstyrene; Diene monomers such as butadiene, isoprene and chloroprene; Nitrile monomers such as acrylonitrile and methacrylonitrile; Acrylamide, N-methylacrylamide, N, N -Acrylamides such as dimethylacrylamide. These may be used alone or in combination of two or more.

  Among the (meth) acrylic acid ester copolymers as described above, those having an energy ray polymerizable group in the molecule (so-called adduct polymers) are particularly preferable. Although it does not specifically limit as a method to give an energy-beam polymerizable group in the molecule | numerator of a (meth) acrylic acid ester copolymer, For example, the (meth) acrylic acid ester copolymer (a1 which has a functional group containing monomer unit) ) And an unsaturated group-containing compound (a2) having a substituent that reacts with the functional group.

  As the functional group-containing monomer contained in the component (a1), hydroxyl group-containing acrylates such as 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, and 2-hydroxypropyl methacrylate are preferable.

  As the component (a2), a compound having a functional group that reacts with the hydroxy group of the component (a1) and a polymerizable double bond is preferable. For example, methacryloyloxyethyl isocyanate, meta-isopropenyl-α, α- Examples thereof include dimethylbenzyl isocyanate, methacryloyl isocyanate, allyl isocyanate, glycidyl (meth) acrylate, (meth) acrylic acid, and the like.

  When a (meth) acrylic acid ester copolymer having an energy ray polymerizable group in the molecule is used, the amount of energy ray curable urethane acrylate that is a low molecular weight component can be reduced. It can suppress that the said low molecular weight component from a thing bleeds out. When bleeding out is suppressed, the composition of the hydrophilic pressure-sensitive adhesive composition does not change, so that the adhesive strength does not deteriorate with time as designed. At this time, in the extension molding described later, the hydrophilic pressure-sensitive adhesive composition Separation from the base can be suppressed. Therefore, it is preferable to use a (meth) acrylic acid ester copolymer having an energy ray polymerizable group in the molecule as the component (a2).

  There is no restriction | limiting in particular about the copolymerization form of the said (meth) acrylic acid ester copolymer, Any of a random copolymer, a block copolymer, and a graft copolymer may be sufficient.

  The molecular weight of the (meth) acrylic acid ester copolymer is preferably 300,000 or more, more preferably 350,000 to 2,500,000 in terms of weight average molecular weight. If the weight average molecular weight is less than 300,000, the adhesion to the adherend and the durable adhesion may be insufficient. Considering adhesiveness and durable adhesiveness, the (meth) acrylic acid ester copolymer preferably has a weight average molecular weight of 400,000 to 1,800,000. In addition, the weight average molecular weight in this specification is the value of standard polystyrene conversion measured by the gel permeation chromatography (GPC) method.

  The glass transition temperature (Tg) before energy ray curing of the (meth) acrylic acid ester copolymer is preferably −50 to 0 ° C., and particularly preferably −40 to 0 ° C. When the glass transition temperature (Tg) of the (meth) acrylic acid ester copolymer is in this range, an appropriate balance between adhesive strength and breaking elongation can be achieved. Therefore, when a structure is obtained by creating a shape by elongation molding described later, the glass transition temperature (Tg) before energy ray curing of the (meth) acrylate copolymer can be set as described above. preferable.

(2) Energy ray curable urethane acrylate Energy ray curable urethane acrylate is an oligomeric compound having a (meth) acryloyl group and a urethane bond. Since it has a (meth) acryloyl group in the molecule, it is polymerized by energy ray irradiation. It hardens | cures and it becomes possible to provide high mechanical strength to the structure obtained by the three-dimensional molding.

  The energy ray curable urethane acrylate is obtained, for example, by reacting a polyisocyanate compound, a (meth) acrylate having a hydroxyl group or an isocyanate group, and a polyol compound. Examples of the energy ray curable urethane acrylate include urethane obtained by further reacting a hydroxyl group-containing (meth) acrylate with a terminal isocyanate group-containing urethane prepolymer obtained by reacting a polyol compound and a polyisocyanate compound. Examples thereof include urethane acrylates obtained by further reacting an isocyanate group-containing (meth) acrylate with an acrylate or a terminal hydroxyl group-containing urethane prepolymer obtained by reacting a polyol compound and a polyisocyanate compound.

  Examples of the polyisocyanate compound include isophorone diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, diphenylmethane-4,4′-. And diisocyanates such as diisocyanate.

  Examples of the (meth) acrylate having a hydroxyl group include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, and polyethylene. Examples include glycol (meth) acrylate. Examples of the (meth) acrylate having an isocyanate group include methacryloyloxyethyl isocyanate.

  Examples of the polyol compound include polyol compounds such as alkylene type, polycarbonate type, polyester type, and polyether type. Specifically, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polycarbonate diol, polyester diol, And ether diol.

  Commercially available products can also be used as the energy ray curable urethane acrylate. For example, U-200PA and UA-4200 made by Shin-Nakamura Kogyo Co., Ltd., AU-3110 and AU-3120 made by Tokushiki Co., Ltd., purple light UV-6100B, UV-3210EA and UV-6010EA made by Nippon Synthetic Chemical Industry, Examples thereof include UV-6020EA, EBECRYL 210 and 230 manufactured by Daicel-Cytec Corporation.

  The energy ray curable urethane acrylate may be used alone or in combination of two or more.

  The weight average molecular weight of the energy ray curable urethane acrylate is preferably 1,000 to 12,000, particularly preferably 2,500 to 10,000, and more preferably 4,000 to 8,000. It is preferable. When the weight average molecular weight is 1,000 or more, a sufficient elongation at break can be obtained with the obtained hydrophilic pressure-sensitive adhesive composition, and when it is 12,000 or less, the hydrophilic pressure-sensitive adhesive composition is formed into a sheet ( When forming a pressure-sensitive adhesive layer comprising a hydrophilic pressure-sensitive adhesive composition), an optimum viscosity is expressed.

The glass transition temperature (Tg) after energy beam curing of the energy beam curable urethane acrylate is preferably −40 to 20 ° C., and particularly preferably −20 to 10 ° C. When the glass transition temperature (Tg) of the energy ray curable urethane acrylate is within this range, an appropriate balance between the adhesive strength and the elongation at break can be achieved. Therefore, when obtaining a structure by creating a shape by elongation molding described later, it is preferable to set the glass transition temperature (Tg) after energy beam curing of the energy beam curable urethane acrylate as described above. The glass transition temperature (Tg) of the energy ray curable urethane acrylate is a value after energy ray curing, and this is a difference after irradiation with ultraviolet rays (illuminance 80 mW / cm, integrated light amount 800 mJ / cm ² ). It is a value measured by scanning calorimetry (DSC method).

  The pencil hardness after energy beam curing of the energy beam curable urethane acrylate is preferably B to 5B, particularly preferably 3B to 5B, more preferably 4B to 5B, and 5B. Is most preferred. When the pencil hardness is set to be equal to or higher than 5B, the hydrophilic pressure-sensitive adhesive composition has sufficient hardness after curing, so that the shape can be maintained well. When the pencil hardness is softer than 5B, the shape cannot be maintained, and there is a possibility that the three-dimensional molding cannot be performed. Further, if the pencil hardness is softened to be equal to or less than B, the cured hydrophilic pressure-sensitive adhesive composition does not become brittle, so that brittle fracture of the structure made of the hydrophilic pressure-sensitive adhesive composition is suppressed. Can do. In particular, in the case of obtaining a structure by creating a shape by elongation molding described later, the work of separating the cured hydrophilic pressure-sensitive adhesive composition from the base is performed. The structure is preferably prevented from being destroyed during this operation.

  The content (solid basis) of the energy beam curable urethane acrylate in the energy beam curable resin according to the present embodiment is 50 to 200 parts by mass with respect to 100 parts by mass of the (meth) acrylic acid ester copolymer. In particular, the amount is preferably 70 to 180 parts by mass, and more preferably 80 to 150 parts by mass. When the content of the energy ray curable urethane acrylate is 50 parts by mass or more, sufficient curability is obtained with the obtained hydrophilic pressure-sensitive adhesive composition, and when it is 200 parts by mass or less, it is a high molecular weight component ( The content of the (meth) acrylic acid ester copolymer can be sufficiently secured, and the shape can be maintained when the hydrophilic pressure-sensitive adhesive composition is stored in a sheet state.

(3) Photopolymerization initiator The energy beam curable resin according to the present embodiment contains a photopolymerization initiator, so that the irradiation amount and irradiation time of the energy beam necessary for the polymerization and curing of the energy beam curable urethane acrylate are reduced. Can be reduced.

  The photopolymerization initiator is not particularly limited. For example, benzophenone, acetophenone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzoin benzoic acid, benzoin methyl benzoate, benzoin dimethyl ketal, 2, 4-diethylthioxanthone, 1-hydroxycyclohexyl phenyl ketone, benzyldiphenyl sulfide, tetramethylthiuram monosulfide, azobisisobutyronitrile, 2-chloroanthraquinone, diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide, etc. Can be mentioned. These photoinitiators may be used individually by 1 type, and may be used in combination of 2 or more type.

  The content (solid content basis) of the photopolymerization initiator in the energy beam curable resin according to the present embodiment is 0.05 to 10.0 parts by mass with respect to 100 parts by mass of the energy beam curable urethane acrylate. Is preferably 0.1 to 6.0 parts by mass, and more preferably 0.5 to 4.0 parts by mass.

(4) Other components The energy beam curable resin according to the present embodiment is various additives such as a crosslinking agent, a silane coupling agent, a tackifier, and an antioxidant within a range that does not impair the object of the present invention. An agent, an ultraviolet absorber, a light stabilizer, a softener, a filler, a colorant, a dispersant and the like may be contained as desired.

  Among these other components, the crosslinking agent will be described in more detail. The energy beam curable resin according to the present embodiment contains the appropriate amount of the crosslinking agent, so that the energy beam curable hydrophilic pressure-sensitive adhesive composition described above. Therefore, the elongation at break and the stress relaxation rate can be adjusted, and the respective requirements can be easily satisfied.

  There is no restriction | limiting in particular as a crosslinking agent, From the things conventionally used as a crosslinking agent conventionally in acrylic resin, arbitrary things can be selected suitably and can be used. Examples of such crosslinking agents include polyisocyanate compounds, epoxy resins, melamine resins, urea resins, dialdehydes, methylol polymers, aziridine compounds, metal chelate compounds, metal alkoxides, and metal salts. Isocyanate compounds are preferably used.

  Examples of the polyisocyanate compound include aromatic polyisocyanates such as tolylene diisocyanate, diphenylmethane diisocyanate and xylylene diisocyanate, aliphatic polyisocyanates such as hexamethylene diisocyanate, alicyclic polyisocyanates such as isophorone diisocyanate and hydrogenated diphenylmethane diisocyanate, and the like. , And their biuret bodies, isocyanurate bodies, and adduct bodies that are a reaction product with low molecular active hydrogen-containing compounds such as ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane, and castor oil. These crosslinking agents may be used individually by 1 type, and may be used in combination of 2 or more type.

  The content (solid basis) of the crosslinking agent in the energy beam curable resin according to the present embodiment is 0.01 to 0.4 parts by mass with respect to 100 parts by mass of the (meth) acrylic acid ester copolymer. In particular, the amount is preferably 0.03 to 0.3 part by mass, and more preferably 0.05 to 0.25 part by mass.

[Particulate hydrophilicity-imparting agent]
The composition of the particulate hydrophilicity imparting agent contained in the energy ray-curable hydrophilic pressure-sensitive adhesive composition according to this embodiment is the above-mentioned requirements for mechanical properties (breaking elongation and stress relaxation rate) and the pressure-sensitive adhesive cured layer. It is optional as long as it meets the above-mentioned charging characteristics (charge voltage half-life) requirements that are sometimes required under predetermined conditions.

  Metal-based particles composed of metals or alloys such as Au, Ag, Ni and Cr as particulate hydrophilicity imparting agents; granular materials in which a metal or alloy is formed on the surface of a substance other than metals and alloys; metal oxidation Examples thereof include particles made of a metal-containing compound such as a product; and particles made of a nonmetallic conductive compound such as graphite. Among these, particles made of a metal oxide are preferable because of excellent optical characteristics. Here, the “metal oxide” in the present embodiment means a compound containing a metal element and oxygen. When the metal element and oxygen are not in a stoichiometric composition, for example, a metal oxide having a stoichiometric composition is used. This includes those doped with other elements or compounds. Further, it may be a composite of a plurality of types of oxides (double oxide), and the oxide constituting the double oxide may contain a nonmetallic oxide.

  Specific examples of the particulate hydrophilicity imparting agent comprising the metal oxide according to the present embodiment include tin-doped indium oxide (ITO) powder, gallium-doped zinc oxide (GZO) powder, antimony-doped tin oxide powder, zinc oxide and antimony pentoxide. And a double oxide containing phosphoric acid-doped tin oxide. Among these, the conductive fine particles made of the metal oxide according to this embodiment are one or two selected from the group consisting of double oxides made of zinc oxide and antimony pentoxide, phosphoric acid doped tin oxide and tin doped indium oxide. It is preferable to contain seeds or more.

  The upper limit of the particle diameter of the particulate hydrophilicity imparting agent according to the present embodiment is not particularly limited. From the viewpoint of favorably maintaining the surface properties (particularly surface roughness) of the pressure-sensitive adhesive layer comprising the energy ray-curable hydrophilic pressure-sensitive adhesive composition, the average particle diameter is preferably 1000 nm or less, and preferably 500 nm or less. Is more preferable, and 100 nm or less is particularly preferable.

  The lower limit of the particle diameter of the particulate hydrophilicity imparting agent according to the present embodiment is not particularly limited. When the particle diameter is excessively small, it is difficult to suppress the aggregation and maintain good dispersibility, and there is a concern that quality variation and productivity decrease may be caused. From the viewpoint of avoiding these problems, the average particle size of the particulate hydrophilicity imparting agent according to this embodiment is preferably 1 nm or more, more preferably 3 nm or more, and particularly preferably 5 nm or more. .

  The content of the particulate hydrophilicity imparting agent in the energy ray-curable hydrophilic pressure-sensitive adhesive composition according to the present embodiment is such that the surface of the structure obtained by three-dimensionally molding the hydrophilic pressure-sensitive adhesive composition according to the present embodiment. The degree of hydrophilicity to be possessed, the hydrophilicity imparting ability of the particulate hydrophilicity imparting agent itself, the shape of the structure to be obtained by three-dimensional molding (in other words, the degree of deformation by three-dimensional molding), etc. should be set as appropriate. Is. If the content is excessively small, it will be difficult to obtain the desired hydrophilicity on the surface of the structure after three-dimensional molding, and if it is excessively large, the three-dimensional moldability will be reduced or the resulting structure machine. There is a concern that the characteristics may deteriorate. If an example of a preferable range of the content of the particulate hydrophilicity imparting agent in the energy ray curable hydrophilic pressure-sensitive adhesive composition according to the present embodiment is shown in the case where the particulate hydrophilicity imparting agent is composed of phosphate-doped tin oxide, It is 5 to 60 parts by mass, more preferably 10 to 50 parts by mass, and more preferably 15 to 45 parts by mass with respect to 100 parts by mass of the energy ray curable resin. Further preferred.

  In addition, the energy ray-curable hydrophilic pressure-sensitive adhesive composition according to this embodiment is obtained by mixing the particulate hydrophilicity imparting agent and the energy ray-curable resin, and this hydrophilic pressure-sensitive adhesive composition. In the preparation, the sol in which the metal oxide powder is dispersed in the liquid is used as the particulate hydrophilicity imparting agent according to the present embodiment, so that the particulate hydrophilic property in the obtained hydrophilic pressure-sensitive adhesive composition is used. It is preferable from the viewpoint of enhancing the dispersibility of the imparting agent.

[Adhesive sheet]
1 A of adhesive sheets provided with the layer formed from the energy-beam curable hydrophilic adhesive composition which concerns on this embodiment are shown in FIG. 1, in order from the bottom on the peeling sheet 12 and the peeling surface of the peeling sheet 12. It is comprised from the laminated adhesive layer 11 and the base material 13 laminated | stacked on the adhesive layer 11. As shown in FIG.

  Moreover, the adhesive sheet 1B provided with the layer formed from the energy-beam curable hydrophilic adhesive composition which concerns on this embodiment, as shown in FIG. 2, two release sheets 12a and 12b, and those two sheets The adhesive layer 11 is sandwiched between the two release sheets 12a and 12b so as to be in contact with the release surfaces of the release sheets 12a and 12b. In addition, the release surface of the release sheet in this specification refers to a surface having peelability in the release sheet, and includes both a surface that has been subjected to a release treatment and a surface that exhibits peelability without being subjected to a release treatment. .

  In any of the pressure-sensitive adhesive sheets 1A and 1B, the pressure-sensitive adhesive layer 11 is formed by forming the energy ray-curable hydrophilic pressure-sensitive adhesive composition described above into a sheet shape. Although the thickness of the adhesive layer 11 is suitably determined according to the shaping | molding method etc. of the adhesive sheet 1, it is 1-300 micrometers normally, Preferably it is 5-100 micrometers, Most preferably, it is the range of 10-50 micrometers.

  There is no restriction | limiting in particular as the base material 13, What was used as a base material sheet of a normal adhesive sheet can be used. For example, polyethylene terephthalate, polybutylene terephthalate, polyester film such as polyethylene naphthalate, cellulose film such as triacetyl cellulose, polyurethane film, polyethylene film, polypropylene film, polyvinyl chloride film, polyvinylidene chloride film, polyvinyl alcohol film, ethylene- Plastic films such as vinyl acetate copolymer film, polystyrene film, polycarbonate film, acrylic resin film, norbornene resin film, cycloolefin resin film; foams such as urethane foam and polyethylene foam; fine paper, glassine paper, impregnation Paper such as paper and coated paper; Metal foil such as aluminum and copper; Weaving using fibers such as rayon, acrylic and polyester Or nonwoven; and the like of two or more kinds of those laminates. The plastic film may be uniaxially stretched or biaxially stretched. In the case where the pressure-sensitive adhesive layer 11 is three-dimensionally molded together with the base material 13, the base material 13 is preferably one having flexibility that allows three-dimensional molding.

  Although the thickness of the base material 13 changes with kinds of material and the objective of the adhesive sheet 1, it is not specifically limited, Usually, 10-300 micrometers, Preferably it is 20-150 micrometers, Most preferably, it is 35-80 micrometers.

  As the release sheets 12, 12a, 12b, for example, polyethylene film, polypropylene film, polybutene film, polybutadiene film, polymethylpentene film, polyvinyl chloride film, vinyl chloride copolymer film, polyethylene terephthalate film, polyethylene naphthalate film, Polybutylene terephthalate film, polyurethane film, ethylene vinyl acetate film, ionomer resin film, ethylene / (meth) acrylic acid copolymer film, ethylene / (meth) acrylic acid ester copolymer film, polystyrene film, polycarbonate film, polyimide film A fluororesin film or the like is used. These crosslinked films are also used. Furthermore, these laminated films may be sufficient.

  The release surface of the release sheet (particularly the surface in contact with the pressure-sensitive adhesive layer 11) is preferably subjected to a release treatment. Examples of the release agent used for the release treatment include alkyd, silicone, fluorine, unsaturated polyester, polyolefin, and wax release agents.

  When using two release sheets 12a and 12b like the adhesive sheet 1B, the materials of the two release sheets 12a and 12b may be the same or different. The release sheet 12a and the release sheet 12b are preferably adjusted so that the difference in release force is different, that is, one is a heavy release type release sheet and the other is a light release type release sheet.

  Although there is no restriction | limiting in particular about the thickness of the peeling sheets 12, 12a, 12b, Usually, it is about 20-150 micrometers.

[Method for producing adhesive sheet]
The method for producing the pressure-sensitive adhesive sheet 1A is arbitrary. For example, a coating solution containing the energy ray-curable hydrophilic pressure-sensitive adhesive composition is applied to the release surface of the release sheet 12 and dried to form the pressure-sensitive adhesive layer 11, and then the pressure-sensitive adhesive layer 11. The substrate 13 is laminated on the substrate.

  Moreover, the method of manufacturing the said adhesive sheet 1B is arbitrary. For example, after the application solution containing the energy ray-curable hydrophilic adhesive composition is applied to the release surface of one release sheet 12a (or 12b) and dried to form the adhesive layer 11 The release surface of the other release sheet 12b (or 12a) is superimposed on the adhesive layer 11.

  As a method for applying the coating solution, for example, a bar coating method, a knife coating method, a roll coating method, a blade coating method, a die coating method, a gravure coating method, or the like can be used.

  The embodiment described above is described for facilitating understanding of the present invention, and is not described for limiting the present invention. Therefore, each element disclosed in the above embodiment is intended to include all design changes and equivalents belonging to the technical scope of the present invention.

  For example, the release sheet 12 of the adhesive sheet 1A may be omitted, or one of the release sheets 12a and 12b in the adhesive sheet 1B may be omitted.

[Three-dimensional molding]
As described above, in this embodiment, “three-dimensional molding” refers to a predetermined shape by three-dimensionally extending a processing target (energy ray-curable hydrophilic pressure-sensitive adhesive composition or pressure-sensitive adhesive layer 11 composed thereof). Means a shape creation means for forming Specific means for three-dimensionally extending the object to be processed include a method of bringing a fluid or solid having a predetermined kinetic energy into contact with the object to be processed (blow molding and press molding are specific examples), and raw materials. Examples thereof include a method of holding the composition with a plurality of holding members and relatively changing their holding positions (partial stretch molding or torsion molding is a specific example).

  The energy ray-curable hydrophilic pressure-sensitive adhesive composition according to the present embodiment and the pressure-sensitive adhesive layer 11 formed by forming this energy ray-curable hydrophilic pressure-sensitive adhesive composition into a sheet form are highly three-dimensionally stretched by three-dimensional molding. It is particularly suitable for three-dimensional molding because it has a high elongation at break that can correspond to the above and a sufficient stress relaxation rate that can stably maintain the shape created between the three-dimensional molding and the hardening by energy rays.

  In addition, since it has excellent adhesive strength before curing with energy rays, the hydrophilic adhesive composition or the adhesive layer 11 according to the present embodiment (hereinafter collectively referred to as “adhesive layer” in this description). .) Is attached to the base, and a gas is supplied from a surface facing the pressure-sensitive adhesive layer in the base to a part of the interface between the pressure-sensitive adhesive layer and the base, and by the supplied gas, Forming such that a part is extended away from the base to form a structure having a base, an adhesive interface between the base and the adhesive layer, and a hollow portion formed by the extended adhesive layer Processing is also possible. When energy ray curing is performed in this state, the stretched adhesive layer surrounding the hollow portion is cured, and the adhesive strength at the adhesive interface between the base and the adhesive layer is lowered. A structure having a sufficient strength can be easily removed from the base. In the present embodiment, the three-dimensional molding by this method may be referred to as “extension molding”.

  In addition, in the above description, a method for supplying gas to the interface between the pressure-sensitive adhesive layer and the base (gas injection method) has been shown as one specific example of a method for extending the pressure-sensitive adhesive layer three-dimensionally by extension molding. However, the pressure-sensitive adhesive layer may be stretched three-dimensionally by other methods. Examples of such a method include a foaming agent-containing method, a protrusion push-up method, and a reduced pressure expansion method. Also, the shape of the stretch molding is not particularly limited, and may be, for example, a spherical shape, a hemispherical shape, a columnar shape, or a concavo-convex structure in which they are continuous.

  In particular, it can be used as a microreactor by adopting the shape of a micro flow channel as shown in FIG. 3, and an inflow portion and a confluence portion can be provided as necessary. The manufacturing method of the hydrophilic three-dimensional structure constituting the microreactor shown in FIG. 3 will be briefly described. The base 21 having the surface on which the groove portion 21a corresponding to the shape of the microchannel is formed (FIG. 5A). The pressure-sensitive adhesive layer 11 of the pressure-sensitive adhesive sheet 1 according to this embodiment is attached to the surface. As a result, gas is supplied into, for example, the end portion 22a of the gas supply pipe 22 communicating with the groove portion 21a in the gap portion between the base 21 and the adhesive layer 11, that is, the groove portion 21a (see FIG. 5 (b)). The pressure-sensitive adhesive layer 11 on the groove portion 21a is stretched by the supplied gas, and the surface of the pressure-sensitive adhesive layer 11 opposite to the base 21 is partially raised (FIG. 5C). In this state, the energy ray-curable hydrophilic pressure-sensitive adhesive composition forming the pressure-sensitive adhesive layer 11 is cured by irradiating energy rays such as ultraviolet rays. By peeling the cured product from the base 21, a hydrophilic three-dimensional structure 23 forming a microreactor is obtained (FIG. 5D). Thus, if the adhesive sheet 1 which concerns on this embodiment is used, the micro reactor provided with the inflow part and the confluence | merging part can be especially manufactured by expansion molding.

From the viewpoint of facilitating shape creation by stretch molding, the energy ray-curable hydrophilic pressure-sensitive adhesive composition according to the present embodiment, when the pressure-sensitive adhesive layer 11 is formed from this composition, is subjected to JIS under the following measurement conditions. The adhesive strength of the pressure-sensitive adhesive layer 11 measured according to Z0237 is preferably 5 N / 25 mm or more before curing and 1 N / 25 mm or less after curing. This adhesive strength is 9 N / 25 mm or more before curing, and more preferably 0.5 N / 25 mm or less after curing.
Adhesive sheet: a pressure-sensitive adhesive layer 11 having a thickness of 20 μm formed on a film made of polyethylene terephthalate having a thickness of 25 μm Substrate: stainless steel plate, SUS304 # 360
Application time: 24 hours (23 ° C, 50RH)

As the energy rays irradiated for curing the three-dimensionally shaped pressure-sensitive adhesive layer, energy rays generated from various energy ray generators are used, and usually ultraviolet rays, electron beams and the like are used. For example, as ultraviolet rays, ultraviolet rays radiated from an ultraviolet lamp are usually used. As this ultraviolet lamp, an ultraviolet lamp such as a high-pressure mercury lamp, a fusion H lamp, or a xenon lamp that emits ultraviolet light having a spectral distribution in a wavelength range of 300 to 400 nm is usually used, and the irradiation amount is usually 50 to 3000 mJ. / Cm ² is preferred. In the case of an electron beam, the irradiation dose is preferably about 10 to 1000 krad.

  EXAMPLES Hereinafter, although an Example etc. demonstrate this invention further more concretely, the scope of the present invention is not limited to these Examples etc.

[Example 1]
(1) Preparation of hydrophilic pressure-sensitive adhesive composition As a (meth) acrylic acid ester copolymer, an acrylic acid ester copolymer obtained by copolymerizing 90 parts by mass of butyl acrylate and 10 parts by mass of acrylic acid (weight average molecular weight 65 100 parts by mass (solid content) of an ethyl acetate / toluene mixed solvent, glass transition temperature -45 ° C., solid content concentration of 26% by mass) and energy ray curable urethane acrylate oligomer (manufactured by Nippon Synthetic Chemical Industry, UV- 6100B, weight average molecular weight 6700, glass transition temperature 0 ° C., pencil hardness 5B after curing) 100 parts by mass (solid content) and isocyanate-based crosslinking agent (manufactured by Nippon Polyurethane Co., Ltd., Coronate L, solid content concentration 75% by mass) 0 0.05 parts by mass (solid content) and 1-hydroxy-cyclohexyl-phenyl-ketone (Ciba Specialty) as a photopolymerization initiator Tea Chemicals Co., Ltd., Irgacure 184) 3.0 parts by mass (more energy ray curable resin component), conductive tin oxide sol (Nissan Chemical Industries Co., Ltd., Celnax CX-S303IP, average particle size) 30 parts by mass of (diameter 5-20 nm) was mixed to prepare an energy ray-curable hydrophilic pressure-sensitive adhesive composition.

(2) Production of pressure-sensitive adhesive sheet Heavy release type release sheet (manufactured by Lintec Corporation, manufactured by releasing the energy ray-curable hydrophilic pressure-sensitive adhesive composition prepared in (1) above with a silicone-based release agent on one side of a polyethylene terephthalate film. SP-PET38T103-1, with a thickness of 38 μm) was applied so that the dry film thickness was 20 μm, and dried at 110 ° C. for 2 minutes to form two types of pressure-sensitive adhesive layers having different thicknesses. To each of the obtained pressure-sensitive adhesive layers, a release surface of a light release type release sheet (SP-PET 381031, thickness 38 μm, manufactured by Lintec Co., Ltd.) obtained by peeling one surface of a polyethylene terephthalate film with a silicone-based release agent was bonded. The layer was sandwiched between two release sheets. Thereafter, the film was aged for 7 days under the conditions of 23 ° C. and 50% RH to obtain an adhesive sheet. Moreover, in order to use for evaluation of a haze and a total light transmittance, the thing with a dry film thickness of 5 micrometers was produced similarly.

[Example 2]
The (meth) acrylic acid ester copolymer contained in the energy ray-curable hydrophilic pressure-sensitive adhesive composition in Example 1 is obtained by adding 52 parts by mass of butyl acrylate, 20 parts by mass of methyl methacrylate, and 28 parts by mass of 2-hydroxyethyl acrylate. Copolymerized (meth) acrylic acid ester copolymer (methacryloyloxyethyl isocyanate (MOI) is reacted with 90 equivalents added per 100 equivalents of hydroxy groups of (meth) acrylic acid ester copolymer, weight average A pressure-sensitive adhesive sheet was prepared in the same manner as in Example 1 except that the molecular weight was 580,000, the mixed solvent of ethyl acetate / toluene, the glass transition temperature before the MOI reaction was −22 ° C., and the solid content was 35% by mass. did.

Example 3
About the particulate hydrophilicity imparting agent in Example 1, it was changed to 20 parts by mass of zinc antimonate (manufactured by Nissan Chemical Industries, Cellax CX-Z210IP, average particle size 5-30 nm) in the same manner as in Example 2. An adhesive sheet was prepared.

Example 4
A pressure-sensitive adhesive sheet was obtained in the same manner as in Example 2, except that the particulate hydrophilicity imparting agent in Example 1 was changed to 40 parts by mass of indium tin oxide (ITO) powder (Mitsubishi Materials Electronics Chemical Co., Ltd., average particle size 30 nm). Produced.

[Comparative Example 1]
Instead of the particulate hydrophilicity imparting agent in Example 1, an adhesive sheet was prepared in the same manner as in Example 2 except that 10 parts by mass of an ionic liquid (tetra-n-octylphosphonium promide) was used as the hydrophilicity imparting agent. Produced.

[Comparative Example 2]
The (meth) acrylic acid ester copolymer in the energy ray curable conductive pressure-sensitive adhesive composition in Example 2 was changed to 30 parts by mass (solid content) of acrylic resin (manufactured by Mitsubishi Rayon Co., Ltd., Dialnal BR-115), Instead of the energy ray curable urethane acrylate oligomer, 100 parts by mass (solid content) of dihydrocyclopentadiethyl acrylate (DCPA) was used. Except for these changes, an adhesive sheet was produced in the same manner as in Example 2.

[Comparative Example 3]
In the composition of the energy ray-curable hydrophilic pressure-sensitive adhesive composition in Example 1, a pressure-sensitive adhesive sheet was produced in the same manner as in Example 1 except that the particulate hydrophilicity imparting agent was not included.

[Test Example 1] (Measurement of elongation at break)
Plural pressure-sensitive adhesive layers having a thickness of 20 μm are used so that the total thickness of the pressure-sensitive adhesive layers in the pressure-sensitive adhesive sheets obtained in Examples or Comparative Examples is 500 μm, and only the outermost release sheet of the laminate remains. The layers were laminated and left for 2 weeks in an atmosphere of 23 ° C. and 50% RH. Then, a 15 mm wide x 55 mm long sample is cut out from the pressure sensitive adhesive sheet in which a plurality of the above adhesive layers are laminated, and the release sheet laminated on the outermost layer of the laminate is peeled off so that the sample measurement range becomes 15 mm wide x 25 mm long The sample was set in a universal tensile testing machine (manufactured by Shimadzu Corporation, Autograph AG-10kNIS). The sample was stretched at a tensile rate of 200 mm / min in an environment of 23 ° C. and 50% RH, and the elongation at the time when the sample broke was defined as the breaking elongation. The results are shown in Table 1.

[Test Example 2] (Stress relaxation rate measurement)
Plural pressure-sensitive adhesive layers having a thickness of 20 μm are used so that the total thickness of the pressure-sensitive adhesive layers in the pressure-sensitive adhesive sheets obtained in Examples or Comparative Examples is 500 μm, and only the outermost release sheet of the laminate remains. The layers were laminated and left for 2 weeks in an atmosphere of 23 ° C. and 50% RH. Then, a 15 mm wide x 55 mm long sample is cut out from the pressure sensitive adhesive sheet in which a plurality of the above adhesive layers are laminated, and the release sheet laminated on the outermost layer of the laminate is peeled off so that the sample measurement range becomes 15 mm wide x 25 mm long The sample was set in a universal tensile testing machine (manufactured by Shimadzu Corporation, Autograph AG-10kNIS). Then, in an environment of 23 ° C. and 50% RH, the sample was stretched to 300% at a tensile speed of 200 mm / min and stopped, and the stress A (Pa) at the time when the elongation was stopped and the stress 300 seconds after the elongation was stopped. B (Pa) was measured. From the measured stress A and stress B, the stress relaxation rate (%) was calculated using the following equation. The results are shown in Table 1.
Stress relaxation rate (%) = {(A−B) / A} × 100 (%)

[Test Example 3] (Measurement of half-life)
A 38 μm thick polyester film (Lumirror, manufactured by Toray Industries, Inc.) is laminated to the pressure sensitive adhesive layer exposed by peeling off the light release sheet of the pressure sensitive adhesive sheet having a thickness of 20 μm obtained in Examples or Comparative Examples. A sample for half-life measurement was prepared. The pressure-sensitive adhesive layer is cured by irradiating ultraviolet light (illuminance 120 mW, light quantity 70 mJ) with an ultraviolet irradiation device (manufactured by FUSION, CV-110O-G) to the obtained half-life measurement sample, and the resulting adhesive is cured The pressure-sensitive adhesive sheet having a layer was left in an environment of 23 ° C. and 50% RH for one day, and then the heavy release sheet was peeled off in the same environment, and a charge decay measuring device (Static Honesteter Type S-5109, manufactured by Sicid Electrostatic Co., Ltd.) was used. Thus, the half-life of the charged voltage in the pressure-sensitive adhesive layer after curing was measured in accordance with JIS L1094: 1997. The results are shown in Table 1. In Table 1, the half of the charged voltage was measured by the above method. The maximum value of the charged voltage of the pressure-sensitive adhesive cured layer measured when measuring the period was also shown.

[Test Example 4] (Haze measurement)
The pressure-sensitive adhesive sheet having a thickness of 5 μm obtained in the example or the comparative example was sampled to a size of 50 mm × 50 mm. About the adhesive layer which removed the peeling sheet from this adhesive sheet, haze was measured according to JISK7136: 2000 using the haze meter (Nippon Denshoku make, NDH-2000). The results are shown in Table 1.

[Test Example 5] (Measurement of total light transmittance)
The pressure-sensitive adhesive sheet having a thickness of 5 μm obtained in the example or the comparative example was sampled to a size of 50 mm × 50 mm. About the adhesive layer which removed the peeling sheet from this adhesive sheet, the total light transmittance was measured according to JISK7361: 1997 using the haze meter (Nippon Denshoku Co., Ltd. make, NDH-2000). The results are shown in Table 1.

[Test Example 6] (Evaluation of stretch moldability)
About the adhesive sheet obtained by the Example or the comparative example, as shown in FIG. 4, evaluation of the stretch moldability was performed. Specifically, the light release type release sheet 12a of the pressure sensitive adhesive sheet 1B is peeled off (FIG. 4 (a)), and the exposed pressure sensitive adhesive layer 11 is made of a stainless steel (SUS304) microsyringe 14 (manufactured by Hamilton, capacity 5 μl). , 95RN type, needle 22S PT-3), the tip of the needle was pressed (FIG. 4B). Then, the heavy release type release sheet 12b was peeled off, and the tip of the needle of the microsyringe 14 was buried to a thickness of 10 μm of the adhesive layer 11 (FIG. 4C).

Next, 4 μl of air was injected from the tip of the needle into the pressure-sensitive adhesive layer 11 using the microsyringe 14, and the pressure-sensitive adhesive layer 11 was deformed only in the portion where the needle tip was buried (FIG. 4D). Thereafter, ultraviolet rays (illuminance 120 mW, light amount 70 mJ) were irradiated by an ultraviolet irradiation device 15 (FUSION, CV-110O-G) (FIG. 4 (e)), and the resulting adhesive cured layer 11 was removed from the tip of the needle. It removed (FIG.4 (f)). Table 1 shows the result of observing the resin shape of the deformed portion of the pressure-sensitive adhesive cured layer 11. The evaluation criteria for the observed resin shape are as follows.
A: The resin shape is almost spherical.
B: The resin shape did not swell more than the hemisphere or wrinkles occurred before it swelled into the hemisphere.
C: The resin did not swell and the shape was not adjusted. Alternatively, it was destroyed when removed from the needle, or peeled off from the needle tip before swelling.
The results are shown in Table 1.

[Test Example 7] (Adhesive strength measurement)
About the adhesive sheet whose thickness of the adhesive layer obtained by the Example or the comparative example was 20 micrometers, the polyester film (the Toray Industries make, Lumirror) of 25 micrometers in thickness was applied to the adhesive layer which peeled and exposed the light release sheet. Lamination was performed to prepare an adhesive sheet for measuring adhesive force.
Next, the sample was sampled to a size of 25 mm × 300 mm, and the surface of the pressure-sensitive adhesive layer which was exposed by peeling the heavy release sheet was reciprocated once on the adherend (stainless steel plate, SUS304 # 360) with a 2 kg roller. Affixed and left in an environment of 23 ° C. and 50% RH for 24 hours.
Then, using the tensile tester (Orientec Co., Tensilon) under the same environment, the value (N / 25 mm) measured under the conditions of a peeling speed of 300 mm / min and a peeling angle of 180 ° was determined as the adhesive strength before curing. did.
Further, as described above, the surface of the pressure-sensitive adhesive layer is pasted on the adherend and allowed to stand for 24 hours, and then irradiated with ultraviolet rays (illuminance 120 mW, light amount 70 mJ) by an ultraviolet irradiation device (FUSION, CV-110O-G). Similarly, a value (N / 25 mm) measured under the conditions of a peeling speed of 300 mm / min and a peeling angle of 180 ° using a tensile tester (Orientec Co., Ltd., Tensilon) was taken as the adhesive strength after curing.

[Test Example 8] (Ion dissolution test)
An ion elution test cell 30 shown in FIG. 5 was prepared and an ion elution test was performed.
First, an indium tin oxide (ITO) layer 32 is formed by vapor-depositing the pressure-sensitive adhesive layer 31 that is exposed by peeling the light release sheet from the pressure-sensitive adhesive sheet having a thickness of 20 μm obtained in Examples or Comparative Examples. Was affixed to the surface on the ITO layer 32 side of a polyethylene terephthalate (PET) film 33 provided on the surface. Next, the pressure-sensitive adhesive layer 31 was irradiated with ultraviolet rays (illuminance 120 mW, light amount 70 mJ) by using an ultraviolet irradiation device (CV-110O-G, manufactured by FUSION) from the heavy release sheet side of the pressure-sensitive adhesive sheet, and cured. An electrode sheet 34 having a configuration in which the layer 31, the ITO layer 32, and the PET film 33 were laminated in this order was produced.
As shown in FIG. 5, another electrode sheet 34 is prepared. As shown in FIG. 5, these electrode sheets 34 have a gap 35 in which the opposite surfaces of the cured adhesive layer 31 to the ITO layer 32 are 50 μm. The cell 30 for ion elution test was obtained so that it might oppose.
Silicone oil (KF-96, manufactured by Shin-Etsu Chemical Co., Ltd.) was filled in the gap 35 of 50 μm in the ion elution test cell 30 in an environment of 23 ° C. and 50% RH.
The surface of the PET layer 33 opposite to the ITO layer 32 is used as an electrode of the ion elution test cell 30, and a constant voltage (15 kV) is applied to these surfaces. It is evaluated whether or not ions are difficult to elute from the cured adhesive layer 31 into the silicone oil depending on whether the change in the current value was almost not observed (A) or the current value increased (F). did.
A: Almost no change in current value was observed F: Increase in current value was confirmed

  As is apparent from Table 1, the energy ray-curable hydrophilic pressure-sensitive adhesive composition obtained in the examples that satisfies the requirements of the present invention is excellent in three-dimensional moldability, and the cured product of such a composition has sufficient hydrophilicity. It was something to prepare.

  The hydrophilic structure formed by three-dimensionally molding the energy ray-curable hydrophilic pressure-sensitive adhesive composition and pressure-sensitive adhesive sheet of the present invention and further curing the energy ray is suitably used for applications requiring hydrophilicity such as a microreactor. can do.

DESCRIPTION OF SYMBOLS 1A, 1B ... Adhesive sheet 11 ... Adhesive layer 12, 12a, 12b ... Release sheet 13 ... Base material 14 ... Micro syringe 15 ... Ultraviolet irradiation apparatus 21 ... Base 21a ... Groove part 22 ... Gas supply pipe 22a ... End part Opening 23 ... hydrophilic three-dimensional structure 30 ... ion elution test cell 31 ... adhesive layer 32 ... indium tin oxide (ITO) layer 33 ... polyethylene terephthalate (PET) film 34 ... electrode sheet 35 ... gap between electrode sheets

Claims (11)

An energy beam curable hydrophilic pressure-sensitive adhesive composition comprising an energy beam curable resin and a particulate hydrophilicity imparting agent dispersed in the energy beam curable resin,
The average particle diameter of the particulate hydrophilicity-imparting agent is 1000 nm or less,
The energy beam curable resin contains a (meth) acrylic acid ester copolymer and an energy beam curable urethane acrylate,
The content of the energy ray curable urethane acrylate is 50 to 200 parts by mass with respect to 100 parts by mass of the (meth) acrylic acid ester copolymer,
The glass transition temperature (Tg) before energy beam curing of the (meth) acrylic acid ester copolymer is −50 to 0 ° C., and the glass transition temperature (Tg) after energy beam curing of the energy beam curable urethane acrylate. ) Is −40 to 20 ° C.,
The energy ray curable hydrophilic pressure-sensitive adhesive composition has an elongation at break of 2000% or more and a stress relaxation rate of 70% or more and 95% or less before energy ray curing.
The energy ray-curable hydrophilic pressure-sensitive adhesive composition is a pressure-sensitive adhesive layer having a thickness of 20 μm formed on a polyethylene terephthalate resin sheet having a thickness of 38 μm, and the pressure-sensitive adhesive layer is cured with energy rays to form a pressure-sensitive adhesive cured layer. The energy ray-curable hydrophilic property, wherein the half-life of the charged voltage measured using a half-life measuring instrument defined in JIS L1094: 1997 is 60 seconds or less at 25 ° C. and 50% RH Adhesive composition. The energy ray-curable hydrophilic pressure-sensitive adhesive composition according to claim 1 , wherein the particulate hydrophilicity imparting agent comprises a metal oxide. The energy according to claim 2 , wherein the metal oxide contains one or more selected from the group consisting of phosphoric acid-doped tin oxide and a double oxide composed of zinc oxide and antimony pentoxide. A wire-curable hydrophilic pressure-sensitive adhesive composition. When the energy ray-curable hydrophilic pressure-sensitive adhesive composition is a pressure-sensitive adhesive layer having a thickness of 5 μm, the total light transmittance before energy ray curing is 80% or more, and the haze of the pressure-sensitive adhesive layer is 10% or less. The energy ray-curable hydrophilic pressure-sensitive adhesive composition according to any one of claims 1 to 3 , wherein Pencil hardness after the energy ray curing of the energy beam curable urethane acrylate, energy beam curable hydrophilic pressure sensitive adhesive composition according to claim 1, any one of 4, which is a B~5B . Energy beam curable hydrophilic pressure sensitive adhesive composition according to any one of claims 1 to 5, characterized in that for use in three-dimensional molded. The energy beam-curable hydrophilic pressure-sensitive adhesive composition according to claim 6 , wherein the energy beam-curable hydrophilic pressure-sensitive adhesive composition is three-dimensionally formed by three-dimensionally stretching. A pressure-sensitive adhesive sheet comprising a pressure-sensitive adhesive layer comprising the energy ray-curable hydrophilic pressure-sensitive adhesive composition according to any one of claims 1 to 7 . A pressure-sensitive adhesive layer composed of the energy ray-curable hydrophilic pressure-sensitive adhesive composition according to any one of claims 1 to 7 ,
An adhesive sheet, comprising: two release sheets sandwiching the adhesive layer. A hydrophilic structure characterized in that the energy ray-curable hydrophilic pressure-sensitive adhesive composition according to any one of claims 1 to 7 is three-dimensionally molded by three-dimensionally stretching. Hydrophilic structure characterized by pressure-sensitive adhesive layer in the pressure-sensitive adhesive sheet according to claim 8 or 9 is those three-dimensional molded by being stretched three-dimensionally.

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