JPWO2016121651A1 - PHOTOSENSITIVE COMPOSITE MATERIAL AND METHOD FOR PRODUCING THE SAME - Google Patents

Abstract

A material that can be used repeatedly as an adhesive is provided. The photosensitive composite material contains a polymer compound, a liquid crystal compound, and a photoresponsive compound. The photoresponsive compound reversibly changes its molecular shape upon irradiation with ultraviolet light and visible light. In the photosensitive composite material, the glass transition temperature is lowered by ultraviolet light irradiation, and the glass transition temperature lowered by the ultraviolet light irradiation is increased by visible light irradiation. The mass of the polymer compound is 40% to 60% of the total mass of the photosensitive composite material, and the mass of the photoresponsive compound relative to the sum of the mass of the liquid crystal compound and the mass of the photoresponsive compound is 2% to 100%. Preferably there is. An azobenzene derivative can be used as the photoresponsive compound.

Description

  The present invention relates to a light-sensitive composite material suitable for uses such as an adhesive film, a self-healing paint, and a self-healing film.

  One of the major features of the adhesive that bonds two objects is that they do not flow. For this reason, if an adhesive is used, an object can be adhere | attached on a vertical surface or a ceiling surface. However, since the pressure-sensitive adhesive is made of a soft material, the strength against the force in the shearing direction is often inferior to an adhesive made of a hard material. From such a technical background, in order to make up for the drawbacks of conventional pressure-sensitive adhesives, the adhesive has the convenience of sticking at the time of sticking and is cured by the action of heat or light after sticking to become an adhesive. "Agent" is attracting attention as an ideal form of adhesive.

  As a thermosetting composition for an adhesive, a composition containing an epoxy resin having two or more epoxy groups in one molecule, a specific solid triazine derivative as a curing agent, and an ionic liquid is known. (Patent Document 1). Moreover, as a photocurable composition for adhesives, a composition containing a compound containing a maleimide group and an ethylenically unsaturated group, a compound containing an ethylenically unsaturated group, and a photopolymerization initiator. Is known (Patent Document 2). These materials all exhibit good properties as an adhesive, but once the adhesive is cured by the action of heat or light, the adherends are peeled off and then reused as an adhesive. There was a problem that it could not be used.

JP 2012-229371 A JP 2009-127023 A

  An object of the present invention is to provide a photosensitive composite material that can be repeatedly used as an adhesive by reversibly changing the hardness of the material.

  The present inventor changed the glass transition temperature by irradiating light-sensitive composite materials containing a polymer compound, a liquid crystal compound, and a photo-responsive compound with light of different wavelengths, and this photo-sensitive composite material. It was found that the hardness of can be reversibly changed. The change in the glass transition temperature of the photosensitive composite material is accompanied by the change in the molecular shape of the photoresponsive material due to light irradiation. Since the hardness of the light-sensitive composite material reversibly changes, the light-sensitive composite material has a function of adhesion and adhesion and can be used repeatedly.

  The photosensitive composite material of the present invention includes a polymer compound, a liquid crystal compound dispersed in a granular form in the polymer compound, a photoresponsive compound whose molecular shape is reversibly changed by irradiation with light of different wavelengths, and Containing. In the light-sensitive composite material of the present invention, the difference between the solubility parameter of the polymer compound and the solubility parameter of the liquid crystal compound is preferably 10 or less. In the light-sensitive composite material of the present invention, the photoresponsive compound may be an azobenzene derivative. In the photosensitive composite material of the present invention, the mass of the polymer compound is preferably 40% to 60% of the total mass.

  In the photosensitive composite material of the present invention, the mass of the photoresponsive compound relative to the sum of the mass of the liquid crystal compound and the mass of the photoresponsive compound is preferably 2% to 100%. Further, in the light-sensitive composite material of the present invention, light of different wavelengths is ultraviolet light and visible light, the glass transition temperature is lowered by ultraviolet light irradiation, and the glass transition temperature lowered by ultraviolet light irradiation is reduced by visible light irradiation. It is preferable to rise.

  The photosensitive composite material film of the present invention is obtained by forming the photosensitive composite material of the present invention into a film shape. The photosensitive composite material film of the present invention can be used as an adhesive film for attaching a decorative article to a nail.

  The method for producing a photosensitive composite material of the present invention includes a polymer compound, a liquid crystal compound dispersed in a granular form in the polymer compound, and an optical response in which the molecular shape reversibly changes by irradiation with light of different wavelengths. A method for producing a light-sensitive composite material containing a photosensitive compound, wherein a polymer compound, a liquid crystal compound, and a photoresponsive compound are dissolved in a volatile organic solvent, and after the dissolution step, A solvent removal step of removing the organic solvent.

  The method for repairing damaged or cut sites of the photosensitive composite material according to the present invention comprises a polymer compound, a liquid crystal compound dispersed in a granular form in the polymer compound, and a molecular shape by irradiation with ultraviolet light and visible light. A method for repairing a damaged or cut site of a photosensitive composite material comprising a photoreactive compound that reversibly changes, wherein the damaged or cut site of the photosensitive composite material is irradiated with ultraviolet light, It has a restoration process for softening the damaged site or sticking the cut site, and a curing step for irradiating the damaged site or the cut site with visible light and curing the damaged site or the cut site after the restoration step.

  The method of using the light-sensitive composite film of the present invention is such that the molecular shape is reversibly changed by irradiation with ultraviolet light and visible light, a polymer compound, a liquid crystal compound dispersed in a granular form in the polymer compound, and ultraviolet light and visible light. A method for using a light-sensitive composite film containing a photoresponsive compound, wherein the light-sensitive composite film is softened by irradiating the light-sensitive composite film with ultraviolet light and softening the light-sensitive composite film. Pressing process for pressing the photosensitive composite material film against the object to be adhered, a pasting process for pasting the adhesive onto the light sensitive composite film pressed against the object to be adhered, and a photosensitive composite material after the pasting process A curing step of irradiating the film with visible light to cure the photosensitive composite material film.

  According to the present invention, a photosensitive composite material that can be used repeatedly as an adhesive is obtained.

The graph which shows the dynamic viscoelasticity measurement result of the photosensitive composite material 1. FIG. The image of the film produced using the photosensitive composite material 1. FIG. The graph which shows the tensile shear test result of the photosensitive composite material 1. FIG. The image which shows the mode of the self-repair of the photosensitive composite material 1. FIG. The graph which shows the evaluation result of the dent repair characteristic of the photosensitive composite material 1. FIG. The graph which shows the dynamic-viscoelasticity measurement result of the photosensitive composite material 2. FIG. The image of the film produced using the photosensitive composite material 2. FIG. The graph which shows the tensile shear test result of the photosensitive composite material 2. FIG. The graph which shows the dynamic viscoelasticity measurement result of the photosensitive composite material 3. FIG. The image of the film produced using the photosensitive composite material 3. FIG. The graph which shows the tensile shear test result of the photosensitive composite material 3. FIG. An image when a film of the photosensitive composite material 3 is provided on the surface of the artificial nail. An image when an ornament is pasted on the film of the photosensitive composite material 3 provided on the surface of the artificial nail.

  The photosensitive composite material of the present invention contains a polymer compound, a liquid crystal compound, and a photoresponsive compound. The liquid crystal compound is dispersed in a granular form in the polymer compound. That is, the polymer compound forms a sponge-like structure in the photosensitive composite material, and the liquid crystal compound is present in the pores of this structure. The photoresponsive compound reversibly changes its molecular shape when irradiated with light of different wavelengths. When the light-sensitive composite material of the present invention is irradiated with light, the molecular shape of the photoresponsive compound changes, and the glass transition temperature of the light-sensitive composite material changes accordingly.

  Therefore, for example, if light sensitive composite material that is hard at room temperature is irradiated with light of wavelength A, the glass transition temperature of the light sensitive composite material is lowered and becomes soft at room temperature. And after adhering adherends through this soft photosensitive composite material, the glass transition temperature of the photosensitive composite material rises by irradiating light of a wavelength B different from the wavelength A, and at room temperature. If it becomes hard, it will be in the state which adherends adhered.

  Thereafter, the light-sensitive composite material is softened by irradiating the light-sensitive composite material with light of wavelength A, and the adherends can be peeled off. As described above, in the photosensitive composite material of the present invention, the soft state and the hard state can be reversibly changed at room temperature by irradiation with light of wavelength A and wavelength B. Therefore, the photosensitive composite material of the present invention can be repeatedly used as an adhesive. Moreover, since the photosensitive composite material of this invention contains a high molecular compound, it can be shape | molded in a film form. A method for forming the film will be described later.

  In the present invention, a general polymer compound can be used as the polymer compound. Specific examples include acrylic polymers, methacrylic polymers, styrene polymers, olefin polymers, vinyl polymers, and the like. These polymer compounds may be used alone or in combination of two or more. A crosslinked polymer compound obtained by chemically crosslinking the polymer compound can also be used. In the present invention, the polymer compound preferably has a weight average molecular weight of 20000 or more. This is because when the weight average molecular weight of the polymer compound is too low, good entanglement between the polymer compounds does not occur and the tackiness and adhesiveness are lowered.

  In the present invention, the mass of the polymer compound is preferably 40% to 90%, more preferably 40% to 60% of the total mass of the photosensitive composite material. In the present application, when “˜” is described between two numerical values to represent a numerical range, these two numerical values are also included in the numerical range. When the mass of the polymer compound in the photosensitive composite material is too small, the polymer compound and the liquid crystal compound are easily separated in the photosensitive composite material, and the adhesive force is reduced. On the other hand, if the mass of the polymer compound in the light-sensitive composite material is too large, the glass transition temperature does not change much even when the light-sensitive composite material is irradiated with light, so that it is difficult to obtain a good adhesive state.

In the present invention, one or more common liquid crystal compounds can be used as the liquid crystal compound. The liquid crystal compound functions as a plasticizer for the polymer compound, and an optimal liquid crystal compound is selected depending on the combination with the polymer compound. In addition, since the liquid crystal compound is dispersed in a granular form in the polymer compound, the polymer chains are entangled in the photosensitive composite material. Therefore, the storage elastic modulus G ′, which is an index of the hardness of the photosensitive composite material, is on the order of 10 ⁵ Pa or more, and this photosensitive composite material is excellent in adhesiveness.

On the other hand, when the polymer compound is included in the liquid crystal compound in a granular form, there is no entanglement between the polymer chains, and G ′ of the photosensitive composite material is on the order of 10 ⁴ Pa at the maximum. For this reason, the photosensitive composite material in which the polymer compound is contained in a granular form in the liquid crystal compound has poor adhesion. The liquid crystal compound preferably exhibits a liquid crystal phase at room temperature. Further, the mass of the liquid crystal compound is preferably 10% to 60%, more preferably 40% to 60% of the entire photosensitive composite material. An example of a liquid crystal compound that can be used in the present invention is 4-cyano-4′-pentylbiphenyl.

  When the mass of the liquid crystal compound in the light sensitive composite material is too large, the polymer compound and the liquid crystal compound are easily separated in the light sensitive composite material, and the adhesive force is reduced. On the other hand, if the mass in the light-sensitive composite material is too small, the glass transition temperature does not drop much even when the light-sensitive composite material is irradiated with light, and the hardness of the light-sensitive composite material does not change much. For this reason, it is difficult to obtain a good adhesion state.

  A suitable combination of the polymer compound and the liquid crystal compound can be determined using the solubility parameter used for the compatibility evaluation between the polymer compound and the plasticizer. In general, it is known that the closer the solubility parameter values of the polymer compound and the plasticizer are, the easier they are to mix, and the farther the solubility parameter value is, the harder they are to mix. In the combination of the polymer compound and the liquid crystal compound used in the light-sensitive composite material of the present invention, the difference in solubility parameter between the two is preferably 10 or less, more preferably 5 or less, and 2 or less. More preferably.

  For example, the solubility parameter of polymethyl methacrylate, which is a polymer compound, is 9.1 to 9.5, and the solubility parameter of 4-cyano-4′-pentylbiphenyl, which is a liquid crystal compound, is 10.95. 1.45 to 1.85. For this reason, the photosensitive composite material using polymethyl methacrylate as the polymer compound and 4-cyano-4′-pentylbiphenyl as the liquid crystal compound is easy to mix with the polymer compound and the liquid crystal compound, and thus has an adhesive force. Is excellent.

  The photoresponsive compound changes its molecular shape due to light absorption, that is, the photoisomerization reaction significantly changes the polarity and molecular size, or changes the phase structure of the liquid crystal compound from the liquid crystal phase to the isotropic phase. It is a compound that can be. Specifically, an azobenzene derivative is mentioned as a photoresponsive compound. When the light-sensitive composite material is irradiated with light, the molecular shape or the like of the photoresponsive compound changes, and the glass transition temperature of the light-sensitive composite material changes accordingly. The photoresponsive compound is preferably dissolved in the liquid crystal compound. By uniformly mixing the light-responsive compound and the liquid crystal compound, the phase structure of the liquid crystal compound is likely to change when the light-sensitive composite material is irradiated with light, and the glass transition temperature of the light-sensitive composite material changes. Because it grows.

  The use of light as a means for reversibly changing the hardness of the photosensitive composite material is overwhelmingly advantageous from the viewpoint of energy saving and high productivity as compared to using heat. The wavelength of the irradiation light is appropriately selected from ultraviolet light, visible light, near infrared light, and the like according to the photoresponsive compound. Among these, light with a wavelength of 254 nm to 1064 nm is preferable, and light with a wavelength of 365 nm to 632 nm is more preferable. Light having a wavelength of 254 nm to 1064 nm can be irradiated from a commercially available general light source, and light having a wavelength of 365 nm to 632 nm is a more versatile light source such as a mercury lamp light source, an argon ion laser light source, or helium-neon. It is because it can irradiate from a laser light source.

From a practical viewpoint, it is preferable that the molecular shape of the photoresponsive compound is reversibly changed by irradiation with ultraviolet light and visible light. That is, for example, it is preferable that the glass transition temperature is lowered by ultraviolet light irradiation, and the glass transition temperature lowered by ultraviolet light irradiation is increased by visible light irradiation. The intensity of the irradiation light is appropriately selected according to the content of the photoresponsive compound in the photosensitive composite material, but is preferably 0.2 mW / cm ² or more. This is because if the intensity of the irradiation light is too small, the photoisomerization reaction of the photoresponsive compound cannot be sufficiently induced. On the other hand, unless the polymer compound, the liquid crystal compound, or the photoresponsive compound is significantly deteriorated or decomposed, the upper limit of the intensity of irradiation light is not particularly limited. However, from a practical viewpoint, 0.2 mW / cm ^{2 to} 200 mW / cm ² is preferable, and 1 mW / cm ^{2 to} 200 mW / cm ² is more preferable.

  The mass of the photoresponsive compound with respect to the sum of the mass of the liquid crystal compound and the mass of the photoresponsive compound is preferably 2% to 100%. If the mass of the photoresponsive compound relative to the sum of the mass of the liquid crystal compound and the photoresponsive compound is too small, the glass transition point due to the photoisomerization reaction of the photosensitive composite material does not sufficiently change, and the photosensitivity The hardness of the composite material does not change much. For this reason, it is difficult to obtain a good adhesion state. In addition, when a photoresponsive compound shows liquid crystallinity at room temperature, a photoresponsive compound can also be used as a liquid crystal compound. That is, only the photoresponsive compound may be used in place of the mixture of the liquid crystal compound and the photoresponsive compound. The mass of the photoresponsive compound with respect to the sum of the mass of the liquid crystal compound and the photoresponsive compound is 100% when the photoresponsive compound exhibits liquid crystallinity at room temperature and only the photoresponsive compound is used. is there.

  The method for producing a photosensitive composite material according to the present invention includes a dissolution step of dissolving a polymer compound, a liquid crystal compound, and a photoresponsive compound in a volatile organic solvent, and then a solvent removal step of removing the organic solvent. And. When the mass ratio of the polymer compound in the light-sensitive composite material increases, the viscosity increases, and even if the polymer compound, liquid crystal compound, and photoresponsive compound are simply mixed, a uniform light-sensitive composite material is obtained. It is difficult. Therefore, a uniform solution is prepared in which a polymer compound, a liquid crystal compound, and a photoresponsive compound are previously dissolved in a volatile organic solvent such as acetone, and then the volatile organic solvent is removed under heating and reduced pressure. By doing so, a uniform light-sensitive composite material can be manufactured.

  Photosensitive composite materials containing a polymer compound, a liquid crystal compound, and a photoresponsive compound whose molecular shape reversibly changes upon irradiation with ultraviolet light and visible light use a soft state guided by ultraviolet light irradiation. By doing so, it is possible to self-repair a damaged site or a cut site. That is, the method for repairing a damaged site or a cut site of the photosensitive composite material of the present invention includes a restoration step and a subsequent curing step.

  In the restoration process, the damaged site or the cut site of the photosensitive composite material is irradiated with ultraviolet light to soften the damaged site or to adhere the cut site. In the curing step, the damaged site or the cut site is irradiated with visible light to cure the damaged site or the cut site. In addition, the damaged site or the cut site is cured by visible light around the photosensitive composite material. Therefore, after the restoration process, the damaged site or the cut site is self-repaired even if it is left without actively irradiating visible light. To do. For this reason, this photosensitive composite material can be applied to self-repairing paints and self-repairing films.

  The light-sensitive composite material of the present invention can naturally restore the dents in addition to the self-healing of damaged sites and cut sites by the above-described restoration process and curing process. When the composition of the polymer compound, liquid crystal compound, and photoresponsive compound is adjusted and the glassy state and the rubbery state of the polymer compound coexist in the composite material, the surface of the material is affected by the elasticity of the polymer compound in the rubbery state. The dent produced in is restored naturally.

  A photosensitive composite film containing a polymer compound, a liquid crystal compound, and a photoresponsive compound whose molecular shape reversibly changes by irradiation with ultraviolet light and visible light can be suitably used as an adhesive. . In this photosensitive composite material film, the adhesiveness based on the soft state induced by ultraviolet light irradiation is sufficient until the molecular shape of the photoresponsive material returns to the shape before ultraviolet light irradiation (for example, at room temperature in a dark place). About 24 hours). For this reason, this photosensitive composite material film is easy to position the adherend on the adherend as compared with an adhesive that hardens immediately.

  Moreover, in this photosensitive composite material film, since the soft state induced | guided | derived by ultraviolet light irradiation can be returned to the hard state before ultraviolet light irradiation by visible light irradiation, adhesiveness can be exhibited. The soft state of the light-sensitive composite material film can be derived not only by irradiation with ultraviolet light but also by heating to a temperature higher than the glass transition temperature of the light-sensitive composite material film. This light-sensitive composite film can be obtained in an arbitrary thickness by uniformly applying pressure while the light-sensitive composite material is soft. This photosensitive composite material film can exhibit tackiness and adhesiveness at an arbitrary size and an arbitrary size by using condensed ultraviolet light or visible light. Since the light-sensitive composite film in a hard state does not exhibit adhesiveness, a false adhesion prevention layer is unnecessary, and storage and handling are easy.

  That is, the usage method of the photosensitive composite material film of this invention is equipped with the softening process, the press process, the sticking process, and the hardening process. In the softening step, the photosensitive composite material film is irradiated with ultraviolet light to soften the photosensitive composite material film. In the pressing step, the softened photosensitive composite material film is pressed against the adherend. In the attaching step, the adhesive is attached to the photosensitive composite material film pressed against the adherend. In the curing step after the pasting step, the photosensitive composite material film is irradiated with visible light to cure the photosensitive composite material film.

  Hereinafter, the present invention will be described in more detail with reference to examples. The content of the present invention is not limited to this embodiment.

(Preparation of photosensitive composite material 1)
Polymethyl methacrylate, a polymer compound (manufactured by Wako Pure Chemical Industries, Ltd., 138-02735, weight average molecular weight is approximately 100,000), 0.40 g, liquid crystal compound, 4-cyano-4′-pentylbiphenyl (Merck Japan Co., Ltd., K-15) 0.57 g, photoresponsive compound 4-butyl-4′-methoxyazobenzene 0.030 g was dissolved in 10 mL of acetone and stirred at 40 ° C. to obtain a uniform solution. Acetone was distilled off under reduced pressure at 60 ° C. to prepare a photosensitive composite material 1. The photosensitive composite material 1 contains 40% by mass of polymethyl methacrylate, 57% by mass of 4-cyano-4′-pentylbiphenyl, and 3% by mass of 4-butyl-4′-methoxyazobenzene.

  4-Butyl-4'-methoxyazobenzene was synthesized by the following procedure. First, 10 g of 4-butylaniline and 100 mL of 2N hydrochloric acid were placed in a beaker. Next, a solution obtained by dissolving 5.5 g of sodium nitrite in 50 mL of water was slowly added to this beaker while maintaining the temperature at 0 ° C., and further stirred at a temperature of 0 ° C. for 1 hour. A solution prepared by dissolving 9.0 g of sodium hydroxide and 9.5 g of phenol in 90 mL of water was dropped into this beaker little by little, and the mixture was stirred at a temperature of 0 ° C. for 2 hours, and further stirred at room temperature for 2 hours. Thereafter, the pH of the solution in the beaker was set to 2 using 2N hydrochloric acid. Next, the precipitate in the beaker was collected by filtration and dissolved in ethyl acetate.

  And after dehydrating this ethyl acetate solution with magnesium sulfate, ethyl acetate was distilled off under reduced pressure, and 12.0 g of crystals of 4-butyl-4′-hydroxyazobenzene as an intermediate were obtained by recrystallization using hexane. . Then, it put into the type | mold flask which made this intermediate body 6.0g, sodium carbonate 3.83g, methyl iodide 5.1g, and acetone 50mL, and stirred under heating-refluxing for 6 hours. Next, the precipitate was collected by filtration and dried under reduced pressure to obtain a crude product. The crude product was purified by column chromatography using chloroform and recrystallized using a mixed solution of methanol and water to obtain 2.4 g of 4-butyl-4'-methoxyazobenzene.

(Dynamic viscoelasticity measurement)
FIG. 1 shows the dynamic viscoelasticity measurement result of the photosensitive composite material 1. The photosensitive composite material 1 is installed in a dynamic viscoelasticity measuring apparatus (Anton Paar Japan Co., Ltd., MCR302), using a parallel plate with a diameter of 8 mm, a gap of 500 μm, a temperature of 25 ° C., a strain of 0.1%, and a frequency of 1.0 Hz. The dynamic viscoelasticity was evaluated under the following conditions. The glass transition temperature was 38.3 ° C., and the storage elastic modulus G ′ and the loss elastic modulus G ″ as indices of hardness were 2.4 × 10 ⁵ Pa and 4.0 × 10 ⁵ Pa, respectively. Next, when the photosensitive composite material 1 was measured while being irradiated with ultraviolet light having a wavelength of 365 nm, the glass transition temperature was 21.6 ° C., the storage elastic modulus G ′ was 3.8 × 10 ⁴ Pa, and the loss elastic modulus G. ”Became 2.3 × 10 ⁴ Pa (total irradiation energy 78 J / cm ² ), and it was confirmed that the glass transition temperature of the photosensitive composite material 1 changed and became soft.

Further, when the light-sensitive composite material 1 in the soft state after irradiation with ultraviolet light was measured while being irradiated with visible light having a wavelength of 450 nm, the storage elastic modulus G ′ was 1.2 × 10 ⁵ Pa and the loss elastic modulus G "Became 1.2 × 10 ⁵ Pa (total irradiation energy 108 J / cm ² ). From this result, the hardness of the photosensitive composite material 1 was reversibly controlled by irradiation with ultraviolet light and visible light. I was able to confirm that

(Production of film of photosensitive composite material 1)
A film was prepared using the photosensitive composite material 1 in the following procedure. First, the photosensitive composite material 1 and a stainless steel film spacer having a thickness of 0.12 mm were placed on a slide glass, and then the photosensitive composite material 1 was heated to 60 ° C. to be in a soft state. Next, another glass slide is placed on the soft light-sensitive composite material 1 and the stainless steel film spacer, and the light-sensitive composite material 1 and the stainless steel film spacer are sandwiched between the two glass slides to apply pressure evenly. It was. And after cooling the photosensitive composite material 1 to room temperature, the photosensitive composite material 1 was peeled from the slide glass, and the photosensitive composite material film was obtained. FIG. 2 shows the appearance of a film produced using the photosensitive composite material 1.

(Tensile shear strength measurement)
FIG. 3 shows the result of the tensile shear test of the photosensitive composite material 1. Using a polyethylene film spacer having a thickness of 0.08 mm, a film of photosensitive composite material 1 was produced in the same manner as described above. Next, the film was sandwiched between two glass substrates, heated at 60 ° C. for 3 minutes, and then cooled to room temperature to prepare Sample A having an adhesion area of 1 cm ² . Sample A was installed in a tensile tester (ORIENTEC, TENSILON), and the tensile shear strength of the sample A in the bonded state was evaluated at a temperature of 24.4 ° C. and a tensile speed of 8.3 μm per second. As shown in “Initial” in FIG. 3, the tensile shear strength of Sample A was 0.30 MPa.

On the other hand, a separately prepared film of photosensitive composite material 1 having an area of 1 cm ² and a thickness of 0.08 mm was placed on a glass substrate, and irradiated with ultraviolet light having a wavelength of 365 nm and an irradiation energy of 54 J / cm ² at 25 ° C. And about the sample B which pressed and adhered another glass substrate at 25 degreeC, it carried out similarly to the above, and measured the tensile shear strength. As shown by “UV” in FIG. 3, the tensile shear strength of the sample B in an adhesive state was 0.01 MPa.

Further, a separately prepared film of photosensitive composite material 1 having an area of 1 cm ² and a thickness of 0.08 mm was placed on a glass substrate, and irradiated with ultraviolet light having a wavelength of 365 nm and an irradiation energy of 54 J / cm ² at 25 ° C. Then, another glass substrate was pressed and adhered at 25 ° C., and further, visible light having a wavelength of 450 nm and an irradiation energy of 45 J / cm ^{2 was} irradiated at 25 ° C. to produce a sample C in an adhesive state with an adhesion area of 1 cm ^2. did. When the tensile shear strength of Sample C was measured in the same manner as described above, it was 0.10 MPa as indicated by “Visible” in FIG. From the above, it was possible to reversibly control the adhesive state and the adhesive state by irradiating the photosensitive composite material 1 with ultraviolet light and visible light.

(Self-healing of light-sensitive composite material 1)
FIG. 4 shows how the photosensitive composite material 1 is self-repaired. First, using a glass spacer having a thickness of 1 mm, a film of the photosensitive composite material 1 having a length of 9 mm, a width of 5 mm, and a thickness of 1 mm was produced in the same manner as described above. Next, this film was cut into two at the center using a cutter knife. Thereafter, the cut pieces were brought into contact with each other and irradiated with ultraviolet light having a wavelength of 365 nm and an irradiation energy of 60 J / cm ² , and it was confirmed that the cut surfaces of the pieces were self-repaired and integrated.

(Production of test piece of photosensitive composite material 1 used for natural restoration of dents)
A test piece was prepared using the photosensitive composite material 1 in the following procedure. First, the photosensitive composite material 1 and a glass spacer having a thickness of 1 mm were placed on a slide glass. Thereafter, the photosensitive composite material was heated to 60 ° C. to make it soft. Next, another glass slide was placed on the soft light-sensitive composite material 1 and the glass spacer, and the light-sensitive composite material 1 and the glass slide were sandwiched between two glass slides, and pressure was applied uniformly. And after cooling the photosensitive composite material 1 to room temperature, the photosensitive composite material 1 was peeled from the slide glass, and the photosensitive composite material film was obtained. The obtained film was cut into a circle having a radius of 4 mm with a cutter knife to obtain a test piece for a strain repair property test.

(Recess repair characteristics of photosensitive composite material 1)
FIG. 5 shows the results of evaluating the dent repair characteristics of the photosensitive composite material 1 using a dynamic viscoelasticity measuring apparatus (Anton Paar Japan, MCR302). Place the test piece on the dynamic viscoelasticity measuring device, and use a minus driver type jig with a contact area of 0.05 cm ² , and use a minus driver type jig under conditions of temperature 25 ° C., strain 0%, frequency 0 Hz. The gap between the tip and the apparatus measurement surface was narrowed, and the photosensitive composite material 1 was deformed until the gap value became 0.9 mm (test 1). As shown in test 1 of FIG. 5, the value of the gap at which the flat screwdriver jig comes into contact with the photosensitive composite material 1 and stress is generated was 1.8 mm.

  From there, as the gap was further narrowed, the material surface was dented and the stress increased linearly. When the gap was widened after the gap value became 0.9 mm, the stress decreased, and the jig was separated from the photosensitive composite material 1 when the gap value was about 1.5 mm. After performing the test 1 and leaving the sample for 30 minutes, the same measurement (test 2) as described above was performed. As shown in test 2 of FIG. 5, the gap value at which the jig was brought into contact with the photosensitive composite material and the stress was generated was 1.8 mm, which was the same as in test 1. This indicates that the dent produced by pushing in the flat-blade screwdriver jig has been restored to its original state in 30 minutes, and the dent produced on the surface of the photosensitive composite material 1 is naturally restored. It was confirmed.

(Preparation of photosensitive composite material 2)
Except for changing the weight of polymethyl methacrylate, 4-cyano-4'-pentylbiphenyl, and 4-butyl-4'-methoxyazobenzene to 0.50 g, 0.475 g, and 0.025 g, respectively, Photosensitive composite material 2 was prepared in the same manner as in Example 1. The photosensitive composite material 2 contains 50% by mass of polymethyl methacrylate, 47.5% by mass of 4-cyano-4′-pentylbiphenyl, and 2.5% by mass of 4-butyl-4′-methoxyazobenzene. It is.

(Dynamic viscoelasticity measurement)
The dynamic viscoelasticity of the photosensitive composite material 2 was evaluated in the same manner as in Example 1. FIG. 6 shows the dynamic viscoelasticity measurement result of the photosensitive composite material 2. The photosensitive composite material 2 had a glass transition temperature of 38.3 ° C., a storage elastic modulus G ′ of 7.4 × 10 ⁵ Pa, and a loss elastic modulus G ″ of 1.3 × 10 ⁶ Pa. In addition, when the photosensitive composite material 2 was irradiated with ultraviolet light having a wavelength of 365 nm, the storage elastic modulus G ′ was 3.4 × 10 ⁵ Pa and the loss elastic modulus G ″ was 4.8 × 10 ⁵ Pa. (Total irradiation energy 90 J / cm ² ), it was confirmed that the photosensitive composite material 2 became soft.

Further, when the light-sensitive composite material 2 in the soft state after the ultraviolet light irradiation was measured while being irradiated with visible light having a wavelength of 450 nm, the glass transition temperature was 28.2 ° C. and the storage elastic modulus G ′ was 4.5. × 10 ⁵ Pa, loss elastic modulus G ″ was 7.0 × 10 ⁵ Pa (total irradiation energy 63 J / cm ² ), and the photosensitive composite material 2 became hard. From this result, ultraviolet light and visible light It was confirmed that the hardness of the photosensitive composite material 2 can be reversibly controlled by irradiation.

(Production of film of photosensitive composite material 2)
A film was prepared using the photosensitive composite material 2 in the following procedure. First, after the photosensitive composite material 2 and a polyethylene film spacer having a thickness of 0.05 mm were placed on a slide glass, the photosensitive composite material 2 was heated to 60 ° C. to be in a soft state. Next, another glass slide was placed on the soft light-sensitive composite material 2 and the polyethylene film spacer, and the pressure-sensitive composite material 1 and the polyethylene film spacer were sandwiched between the two glass slides, and pressure was applied uniformly. . And after cooling the photosensitive composite material 2 to room temperature, the photosensitive composite material 2 was peeled from the slide glass, and the photosensitive composite material film was obtained. FIG. 7 shows the appearance of a film produced using the photosensitive composite material 2.

(Tensile shear strength measurement)
FIG. 8 shows the result of the tensile shear test of the photosensitive composite material 2. Using a polyethylene film spacer having a thickness of 0.12 mm, a film of photosensitive composite material 2 was produced in the same manner as described above. Next, this film was sandwiched between two glass substrates, heated at 60 ° C. for 3 minutes, and then cooled to room temperature to prepare Sample D having an adhesion area of 0.25 cm ² . Sample D was evaluated for tensile shear strength in the same manner as in Example 1. As shown in “Initial” in FIG. 8, the tensile shear strength of Sample D was 0.57 MPa.

On the other hand, a separately prepared film of photosensitive composite material 2 having an area of 0.25 cm ² and a thickness of 0.12 mm is placed on a glass substrate, and irradiated at 25 ° C. with ultraviolet light having a wavelength of 365 nm and an irradiation energy of 54 J / cm ^2. did. And about the sample E which pressed and adhered another glass substrate at 25 degreeC, it carried out similarly to the above, and measured the tensile shear strength. As shown in “UV” in FIG. 8, the tensile shear strength of the sample E in an adhesive state was 0.26 MPa.

Further, a separately prepared film of photosensitive composite material 2 having an area of 0.25 cm ² and a thickness of 0.12 mm is placed on a glass substrate, and ultraviolet light having a wavelength of 365 nm and an irradiation energy of 54 J / cm ^{2 is} applied at 25 ° C. After irradiation, another glass substrate was pressed and adhered at 25 ° C., and further, irradiated with visible light having a wavelength of 450 nm and an irradiation energy of 45 J / cm ² at 25 ° C., and an adhesion state of 0.25 cm ² was obtained. Sample F was prepared. When the tensile shear strength of Sample F was measured in the same manner as described above, it was 0.44 MPa as indicated by “Visible” in FIG. From the above, it was possible to reversibly control the adhesive state and the adhesive state by irradiating the photosensitive composite material 2 with ultraviolet light and visible light.

(Preparation of photosensitive composite material 3)
Except for changing the weight of polymethyl methacrylate, 4-cyano-4′-pentylbiphenyl, and 4-butyl-4′-methoxyazobenzene to 0.60 g, 0.38 g, and 0.020 g, respectively, A photosensitive composite material 3 was prepared in the same manner as in Example 1. The photosensitive composite material 3 contains 60% by mass of polymethyl methacrylate, 38% by mass of 4-cyano-4′-pentylbiphenyl, and 2% by mass of 4-butyl-4′-methoxyazobenzene.

(Dynamic viscoelasticity measurement)
The dynamic viscoelasticity of the photosensitive composite material 3 was evaluated in the same manner as in Example 1. FIG. 9 shows the dynamic viscoelasticity measurement result of the photosensitive composite material 3. The storage elastic modulus G ′ of the light-sensitive composite material 3 immediately after preparation was 1.9 × 10 ⁶ Pa and the loss elastic modulus G ″ was 3.2 × 10 ⁶ Pa. Next, ultraviolet light having a wavelength of 365 nm Was measured while irradiating the photosensitive composite material 3, and the storage elastic modulus G ′ was 1.0 × 10 ⁶ Pa and the loss elastic modulus G ″ was 1.9 × 10 ⁶ Pa (total irradiation energy 63 J / cm ² ) It was confirmed that the photosensitive composite material 3 became soft.

Furthermore, when the light-sensitive composite material 3 in a soft state after irradiation with ultraviolet light was measured while being irradiated with visible light having a wavelength of 450 nm, the storage elastic modulus G ′ was 1.5 × 10 ⁶ Pa and the loss elastic modulus G ”Became hard at 2.7 × 10 ⁶ Pa (total irradiation energy 54 J / cm ² ). From this result, the hardness of the photosensitive composite material 3 was reversibly controlled by irradiation with ultraviolet light and visible light. I was able to confirm that it was possible.

(Production of film of photosensitive composite material 3)
A film was prepared using the photosensitive composite material 3 in the same procedure as in Example 2. As a result, a transparent film was obtained. FIG. 10 shows the appearance of a film produced using the photosensitive composite material 3. The light transmittance of this film showed a high value of 90% or more in the wavelength range of 550 nm to 800 nm in the visible light region.

(Tensile shear strength measurement)
FIG. 11 shows the result of the tensile shear test of the photosensitive composite material 3. Using a polyethylene film spacer having a thickness of 0.25 mm, a film of photosensitive composite material 3 was produced in the same manner as described above. Next, this film was sandwiched between two glass substrates, heated at 60 ° C. for 3 minutes, and then cooled to room temperature to prepare a sample G having an adhesion area of 0.25 cm ² . For sample G, the tensile shear strength was evaluated in the same manner as in Example 1. As shown in “Initial” in FIG. 11, the tensile shear strength of the sample G was 1.63 MPa.

On the other hand, a separately prepared film of photosensitive composite material 3 having an area of 0.25 cm ² and a thickness of 0.25 mm is placed on a glass substrate, and irradiated at 25 ° C. with ultraviolet light having a wavelength of 365 nm and an irradiation energy of 54 J / cm ^2. did. And about the sample H which pressed and adhered another glass substrate at 25 degreeC, it carried out similarly to the above, and measured the tensile shear strength. As shown in “UV” in FIG. 11, the tensile shear strength of the adhesive sample H was 0.30 MPa.

Further, a separately prepared film of photosensitive composite material 3 having an area of 0.25 cm ² and a thickness of 0.25 mm is placed on a glass substrate, and ultraviolet light having a wavelength of 365 nm and an irradiation energy of 54 J / cm ^{2 is} applied at 25 ° C. After irradiation, another glass substrate was pressed and adhered at 25 ° C., and further, irradiated with visible light having a wavelength of 450 nm and an irradiation energy of 45 J / cm ² at 25 ° C., and an adhesion state of 0.25 cm ² was obtained. Sample I was prepared. When the tensile shear strength of Sample I was measured in the same manner as described above, it was 0.99 MPa as indicated by “Visible” in FIG. From the above, it was possible to reversibly control the adhesive state and the adhesive state by irradiating the photosensitive composite material 3 with ultraviolet light and visible light.

(Transfer to artificial nail and stick nail parts)
First, a film of photosensitive composite material 3 having a thickness of 0.05 mm was produced on a slide glass. Next, the film was peeled off from the slide glass, adhered onto a commercially available artificial nail made of methacrylic resin, and shaped according to the shape of the artificial nail. Then, at 25 ° C., ultraviolet light having a wavelength of 365 nm and a light intensity of 150 mW / cm ² is irradiated on the film for 300 seconds (irradiation energy is 45 J / cm ² ), and the film of the photosensitive composite material 3 is transferred onto the artificial nail surface. did. The film of the photosensitive composite material 3 transferred to the artificial nail surface is shown in FIG.

Next, the film was further irradiated with ultraviolet light for 300 seconds (irradiation energy was 45 J / cm ² ) to soften the film, and six commercially available acrylic resin stones, which are nail parts, were pressed and adhered. . The film was irradiated with visible light having a wavelength of 450 nm and a light intensity of 100 mW / cm ² at 25 ° C. for 300 seconds (irradiation energy was 30 J / cm ² ), the film was cured to be in an adhesive state, and a nail part was attached. I attached. Thus, the state which affixed the nail part to the artificial nail via the film of the photosensitive composite material 3 is shown in FIG.

In this state, the nail part was able to be detached from the film of the photosensitive composite material 3 by applying a stress of 1 MPa to the nail part. In this state, the entire film is irradiated with ultraviolet light having a wavelength of 365 nm and a light intensity of 150 mW / cm ² for 300 seconds (irradiation energy is 45 J / cm ² ) to soften the film. We were able to.

  The light-sensitive composite material of the present invention can be used for adhesive bonding and painting in a wide range of fields such as artificial bait for fishing, construction, transport machinery, electronics, medicine, and space. Moreover, the sheet | seat and film comprised from the photosensitive composite material of this invention can be used for cosmetics, such as an adhesive agent for nail art.

Claims (11)

A polymer compound;
A liquid crystal compound dispersed in a granular form in the polymer compound;
A photoresponsive compound whose molecular shape reversibly changes by irradiation with light of different wavelengths;
A light sensitive composite material. In claim 1,
A photosensitive composite material in which a difference between a solubility parameter of the polymer compound and a solubility parameter of the liquid crystal compound is 10 or less. In claim 1 or 2,
A photosensitive composite material in which the photoresponsive compound is an azobenzene derivative. In any one of Claim 1 to 3,
A photosensitive composite material in which the mass of the polymer compound is 40% to 60% of the total mass. In any one of Claim 1-4,
The photosensitive composite material whose mass of the said photoresponsive compound with respect to the sum of the mass of the said liquid crystal compound and the mass of the said photoresponsive compound is 2%-100%. In any one of Claim 1 to 5,
The light of different wavelengths is ultraviolet light and visible light,
Photosensitive composite material in which the glass transition temperature is lowered by ultraviolet light irradiation, and the glass transition temperature lowered by ultraviolet light irradiation is increased by visible light irradiation.   A photosensitive composite material film obtained by forming the photosensitive composite material according to claim 1 into a film. In claim 7,
A light-sensitive composite film that is an adhesive film for attaching decorative items to nails. A photosensitive composite material comprising a polymer compound, a liquid crystal compound dispersed in a granular form in the polymer compound, and a photoresponsive compound whose molecular shape reversibly changes upon irradiation with light of different wavelengths. A manufacturing method comprising:
A dissolving step of dissolving the polymer compound, the liquid crystal compound, and the photoresponsive compound in a volatile organic solvent;
After the dissolving step, a solvent removing step for removing the organic solvent;
A method for producing a photosensitive composite material comprising: Photosensitive composite material comprising a polymer compound, a liquid crystal compound dispersed in a granular form in the polymer compound, and a photoresponsive compound whose molecular shape reversibly changes upon irradiation with ultraviolet light and visible light A method for repairing a damaged or cut site of
A restoration step of irradiating the damaged site or the cut site of the photosensitive composite material with ultraviolet light to soften the damaged site or to adhere the cut site;
After the restoration step, a curing step of irradiating the damaged site or the cut site with visible light to cure the damaged site or the cut site;
A method for repairing a damaged site or a cut site of a photosensitive composite material comprising: Photosensitive composite material comprising a polymer compound, a liquid crystal compound dispersed in a granular form in the polymer compound, and a photoresponsive compound whose molecular shape reversibly changes upon irradiation with ultraviolet light and visible light How to use the film,
Irradiating the light-sensitive composite film with ultraviolet light to soften the light-sensitive composite film; and
A pressing step of pressing the softened photosensitive composite material film against an adherend;
An attaching step of attaching an adhesive to the light-sensitive composite film pressed against the adherend;
After the attaching step, a curing step of irradiating the light-sensitive composite material film with visible light to cure the light-sensitive composite material film;
Use of a light-sensitive composite film having

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