JP4328862B2 - Pattern forming body and pattern forming method - Google Patents

Description

  The present invention relates to a novel pattern forming body and a pattern forming method.

Conventionally, materials that change the water wettability of a surface from hydrophobic to hydrophilic or from hydrophilic to hydrophobic using temperature and heat are known. As this material, for example, a copolymer of N-isopropylacrylamide (NIPAM) and an azobenzene derivative has been proposed (for example, Non-Patent Document 1). According to this copolymer, the surface of the copolymer is hydrophilic when the temperature is 29.2 ° C., whereas the surface changes to hydrophobic when the temperature is 31 ° C. Further, when the surface of the copolymer is irradiated with ultraviolet light for 5 minutes at a temperature of 31 ° C., the water wettability of the surface changes from hydrophobic to hydrophilic. Thus, the water wettability of the surface of the copolymer can be changed by changing the temperature of the copolymer or irradiating with light. As another material capable of changing the water wettability of the surface, a lift-off type cell culture support made of a NIPAM polymer that is a temperature-responsive polymer has been proposed (for example, Patent Document 1). This NIPAM polymer becomes hydrophobic at 37 ° C. and becomes hydrophilic at 32 ° C. or below. Therefore, when cells are attached to the surface of the NIPAM polymer and grown at 37 ° C., the cells are attached to the NIPAM polymer. On the other hand, when the NIPAM polymer is set to 32 ° C. or lower, the cells that have been attached so far are detached from the NIPAM polymer. Thus, by changing the water wettability of the surface of the NIPAM polymer from hydrophobic to hydrophilic depending on the temperature, the cultured cells can be easily detached without being destroyed.
Analytical Chemistry, Vol. 71, no. 6, 1125 (1999) WO01 / 068799

  By the way, the above-mentioned materials of Non-Patent Document 1 and Patent Document 1 change the water wettability of the surface by changing the water wettability of the material itself. Even if this change in water wettability is applied to the pattern forming body, it is difficult to form a clear pattern on the surface of the material. Conventionally, a pattern forming body using hydrogel is not known.

  The present invention has been made in view of the above-described problems, and an object thereof is to provide a novel pattern forming body and a pattern forming method capable of forming a clear pattern.

  In creating a pattern-forming body capable of forming a clear pattern, the present inventors paid attention to the characteristics of hydrogel such as water wettability and flexibility, and are azobenzene that is hydrophobic and changes its three-dimensional structure by light irradiation. As a result of chemical modification of the compound having a structure or a photocrosslinkable group that forms a crosslink on the surface of the hydrogel, it does not change the water wettability of the hydrogel or these photoresponsive compounds themselves. Due to the change in the behavior of the responsive compound, the water wettability of the surface of the pattern forming body could be greatly different between the exposed part and the non-exposed part. Therefore, the present invention has been completed with this fact as a concept for designing a new pattern forming material.

  That is, the pattern forming body of the present invention is a pattern forming body that can form a pattern by utilizing the difference in water wettability between the exposed portion and the non-exposed portion when irradiated with light. A surface-modifying part formed by chemically bonding a hydrophobic photoresponsive substance whose association state changes or a cross-linking state changes to the surface of the hydrogel, and the surface-modifying part is brought into contact with water. In this state, when the hydrophobic photoresponsive substances are weakly associated with each other or when a crosslink is not formed, the hydrophobic photoresponsive substances are covered with the hydrogel and become hydrophilic. When strongly associated or when a crosslink is formed, it is covered with the hydrophobic photoresponsive substance and becomes hydrophobic.

  When the surface of the pattern formed body is irradiated with light, among the hydrophobic photoresponsive substances chemically bonded to the surface of the hydrogel, the association state of the photoresponsive substance changes in the exposed part or the crosslinked formation state. Changes. That is, the photoresponsive substances associate weakly or strongly with each other by light irradiation, or form a crosslink or break the crosslink. When the photoresponsive materials are weakly associated with each other or when no crosslinks are formed, the photoresponsive materials are allowed to move on the surface of the hydrogel. For this reason, when the surface modification part of a pattern formation body is made to contact water, hydrogel will take in the hydrophobic photoresponsive substance inside a hydrogel, and the surface will be exposed to water. As a result, the surface of the pattern forming body becomes hydrophilic. On the other hand, when the photoresponsive substances are strongly associated with each other or when a crosslink is formed, the movement of the photoresponsive substance on the surface of the hydrogel is suppressed. For this reason, when the surface modification part of a pattern formation body is made to contact water, the surface of hydrogel will remain covered with the hydrophobic photoresponsive substance. As a result, the surface of the pattern forming body becomes hydrophobic. As described above, when the surface of the pattern forming body is irradiated with light, the hydrophilicity and hydrophobicity of the surface of the pattern forming body can be changed drastically between the exposed and non-exposed portions. As a result, a clear pattern can be formed when a hydrophobic substance or a hydrophilic substance is adsorbed or desorbed on the surface of the pattern forming body. Note that “when they are weakly meeting each other” includes a state of non-association.

  The pattern forming method of the present invention is a pattern forming method capable of forming a pattern using a difference in water wettability between an exposed portion and a non-exposed portion when irradiated with light. After irradiating the part with light, the exposed part and the non-exposed part are provided, and then a pattern is formed by adsorbing the hydrophobic substance or hydrophilic substance, or after adsorbing the hydrophobic substance or hydrophilic substance on the whole. A pattern is formed by removing a hydrophobic substance or a hydrophilic substance adsorbed on the exposed portion by irradiating a part of the light to one of the lights in the first and second wavelength ranges. After irradiating the entire surface and then adsorbing a hydrophobic substance or a hydrophilic substance, the other part of the light in the first and second wavelength ranges is irradiated with a part of the exposed part and the non-exposed part. After setting the exposure section And it forms a pattern by peeling the adsorbed hydrophobic material or hydrophilic material.

  According to this pattern forming method, when the surface of the pattern forming body is irradiated with light, the hydrophilicity and hydrophobicity of the surface of the pattern forming body change drastically between the exposed portion and the non-exposed portion. A clear pattern can be formed when a hydrophobic substance or a hydrophilic substance is adsorbed or desorbed on the surface of the pattern forming body. Here, the first wavelength range and the second wavelength range differ depending on the type of the photoresponsive substance. For example, the first wavelength range is the ultraviolet wavelength range and the second wavelength range is visible. It is good also as a wavelength range of light, and it is good also considering the 1st wavelength range as the wavelength range of visible light, and making the 2nd wavelength range into the wavelength range of ultraviolet light.

  The pattern formed body of the present invention is a pattern formed body that can form a pattern by utilizing the difference in water wettability between the exposed portion and the non-exposed portion when irradiated with light, and is associated with the hydrogel by light irradiation. Or a surface modification part formed by chemically bonding a hydrophobic photoresponsive substance whose crosslink formation state changes to the surface of the hydrogel, wherein the surface modification part is in contact with water. Then, when the hydrophobic photoresponsive substances are weakly associated with each other or when a crosslink is not formed, the hydrophobic photoresponsive substances are covered with the hydrogel and become hydrophilic, and the hydrophobic photoresponsive substances are strongly associated with each other. When this is done or when a cross-link is formed, it is covered with the hydrophobic photoresponsive substance and becomes hydrophobic.

  Here, as long as the hydrogel is a gel using water or an aqueous solvent such as water / water-soluble organic solvent as a dispersion medium, the type of gel and the structure of the crosslinking group are not particularly limited. Either a gel or a physical gel or a chemical gel may be used. This hydrogel preferably has a hydroxyl group, an amino group, or a carboxyl group in the hydrogel in order to chemically bond a photoresponsive substance on the surface thereof. In addition, the material of the substrate used for producing the hydrogel is not particularly limited, and examples thereof include one or more selected from the group consisting of metals, ceramics, glass, quartz, and plastics. . The shape of the substrate is not particularly limited, and examples thereof include a sheet shape and a block shape. The film thickness of the hydrogel is not particularly limited because the pattern-formed product of the present invention is patterned on the surface of the hydrogel, and may be appropriately selected depending on the application.

  The photoresponsive substance may be a hydrophobic substance whose association state is changed by light irradiation or whose crosslinking formation state is changed. The type of the hydrophobic photoresponsive substance is not particularly limited. For example, the hydrophobic photoresponsive substance includes a structure in which a cis isomer and a trans isomer are changed by light irradiation, and is irradiated with light in the first wavelength range. It may be weakly associated with each other as a cis isomer, and may be strongly associated with each other when irradiated with light in the second wavelength range, and specifically includes those containing an azobenzene structure. The azobenzene structure is weakly associated with each other when irradiated with light in the first wavelength range, and is weakly associated with each other when irradiated with light in the second wavelength range. For example, What has a structure represented by following formula (1) is mentioned. Here, R in the following formula (1) is not particularly limited, but an alkyl group having 1 to 11 carbon atoms, an alkoxyl group, a halogenated alkyl group, a halogenated alkoxyl group, and a cyano group are preferable. Of these, alkyl groups having 1 to 11 carbon atoms, alkoxyl groups, halogenated alkyl groups, and halogenated alkoxyl groups are less susceptible to steric hindrances (for example, inhibiting photosensitivity), thereby reducing the hydrophobicity of the photoresponsive substance. From the viewpoint of enhancing, a cyano group is preferable from the viewpoint of promoting cis-trans photoisomerization of an azobenzene structure, which is less likely to cause steric hindrance. This azobenzene structure is usually a thermally stable trans form and is in an associated state because it is a rod-like molecule. When this associated azobenzene structure is irradiated with ultraviolet light (eg, 365 nm), the azobenzene structure changes from a trans form to a cis form, and the molecular structure, polarity, and dipole orientation change. As a result, the photoresponsive substances are not associated with each other. On the other hand, when visible light (for example, 436 nm) is irradiated to an unassociated azobenzene structure, the azobenzene structure changes from a cis form to a trans form. As a result, the photoresponsive substances become rod-like molecules and strongly associate with each other. In addition, the cis isomer of the azobenzene structure behaves like a polar group by exposing the unshared electron pair of the nitrogen atom due to its molecular structure. For this reason, hydrophilicity increases in the cis isomer having an azobenzene structure. Alternatively, the hydrophobic photoresponsive substance includes a structure that changes from a state in which no crosslink is formed by light irradiation to a state in which a crosslink is formed, and does not form a crosslink before irradiation with light in a predetermined wavelength range. Further, after irradiation with light in a predetermined wavelength range, a crosslink may be formed. Specific examples include those containing one selected from the group consisting of a cinnamate structure, a styrylpyridine structure, a coumarin structure and a chalcone structure. Here, the cinnamate structure, the styrylpyridine structure, the coumarin structure, and the chalcone structure are structures represented by the following formulas (2) to (7), respectively. If the photoresponsive substance contains these photocrosslinkable groups, the photoresponsive substance is not cross-linked to form a cross-linkage between molecules by light irradiation (eg, 313 nm in cinnamate structure). Can be changed. As photo-responsive substances, the cinnamate structure, styrylpyridine structure, coumarin structure and chalcone structure are difficult to return to the original structure where no crosslinks are formed once they are formed by light irradiation. An azobenzene structure that exhibits a good reversible reaction upon irradiation is more preferred.

(However, R is one selected from the group consisting of an alkyl group having 1 to 11 carbon atoms, an alkoxyl group, a halogenated alkyl group, a halogenated alkoxyl group, and a cyano group.)

  In the pattern forming body of the present invention, the photoresponsive substance is chemically bonded to the hydrogel, but the type of this chemical bond is not particularly limited. Examples thereof include an ester bond, a urethane bond, an ether bond, an amide bond, an amino bond, and a carbonate bond. Specifically, any one of a carboxylic acid chloride structure, an isocyanate structure, and an epoxy structure is reacted with a hydroxyl group to chemically bond a photoresponsive substance and a hydrogel, or any one of a halogen atom and a carboxyl group and an amino group. The photoresponsive substance and the hydrogel are chemically bonded by reacting the group, or the photoresponsive substance and the hydrogel are chemically bonded by reacting the amino group and the carboxyl group.

  In the pattern forming body of the present invention, the photoresponsive substance may have any of the above formulas (1) to (7) directly bonded to the hydrogel, but the water wettability of the surface of the pattern forming body. In order to change greatly, it is preferable that it is chemically bonded to the hydrogel through a spacer structure that increases the molecular length of the photoresponsive substance. The spacer structure is not particularly limited, but is preferably a structure composed of a linear alkylene chain, an ethylene oxide unit composed of ethylene oxide, or a combination thereof because of the versatility of the synthetic raw material. Of these, linear alkylene chains having less than 2 carbon atoms are less effective in increasing the length of the photoresponsive substance, and linear alkylene chains having 13 or more carbon atoms are expensive. Chains are preferred. Moreover, what consists of a combination of the ethylene oxide unit comprised by 1-3 ethylene oxide or this ethylene oxide unit and a C2-C12 linear alkylene chain from the versatility of a synthetic material is preferable.

  When producing the pattern forming body of the present invention, the type of gel medium for chemically bonding the photoresponsive substance is not particularly limited as long as the surface of the hydrogel is finally modified with the photoresponsive substance, It may be a hydrogel, a xerogel, or a hydrogel precursor before water is contained in the hydrogel. Among these, since it does not contain a solvent and does not have a porous structure, a hydroprecursor that is relatively easy to react with the photoresponsive substance only in the vicinity of the surface is preferable.

(1) Preparation of hydrogel precursor thin film 2-hydroxylethylmethyl methacrylate (HEMA) 2 g, oligoethylene oxide methyl ether acrylate (manufactured by Nippon Oil & Fats, trade name Blemmer PME-200) 2.8 g, ethylene glycol dimethacrylate (EGDM) 0. 024 g and 2,24-dimethoxy-2-phenylacetophenone 0.024 g were mixed to prepare a photopolymerizable monomer mixture. This mixed solution was cast on a glass substrate (30 mm × 30 mm, t = 1), and a mercury xenon lamp (manufactured by SAN-EI, SUPER CURE-203S) through a UV35 glass filter (manufactured by Toshiba Glass) under a nitrogen stream. Photopolymerization was performed by irradiating light at about ² J / cm ² (40 mW / cm ² ) for 50 seconds at room temperature. Thereafter, the unreacted monomer was washed with acetone to obtain a hydrogel precursor thin film. The hydrogel precursor thin film was scratched to the glass substrate with a spatula, and the film thickness in the cross section was measured with an atomic force microscope (Nanopics 2100, manufactured by Seiko Instruments Inc.). The film thickness was about 1 μm. .

(2) Synthesis of 11- {4-[(4-hexylphenyl) azo] phenoxy} undecanoic acid chloride 4-[(hexyl) azo] phenol was synthesized from hexylaniline and phenol by azo coupling. In addition, 11-bromoundecanoic acid was protected with 3,4-dihydro-2H-pyran, and Williamson ether synthesis was performed with potassium carbonate in 4-[(hexyl) azo] phenol and N, N-dimethylformamide. . The reaction product was extracted with diethyl ether, washed with water, and deprotected with hydrochloric acid in tetrahydrofuran (THF). After concentration, the mixture was extracted again with ether, washed with water, and dried over anhydrous magnesium sulfate. Then, the solvent was removed and recrystallization was performed with a benzene-chloroform mixed solvent to obtain 11- {4-[(4-hexylphenyl) azo] phenoxy} undecanoic acid. After reacting this 11- {4-[(4-hexylphenyl) azo] phenoxy} undecanoic acid and thionyl chloride, unreacted thionyl chloride was distilled off under reduced pressure, and 11- {4-[(4-hexylphenyl) was removed. ) Azo] phenoxy} undecanoic acid chloride (see compound (8) of the following formula).

(3) Preparation of pattern-formed body by surface modification of hydrogel precursor thin film 40 mg of synthesized 11- {4-[(4-hexylphenyl) azo] phenoxy} undecanoic acid chloride (compound (8)), 11.9 mg of triethylamine, 1 mg of 4-dimethylaminopyridine (DMAP) was dissolved in 3 ml of dry toluene. The previously prepared hydrogel precursor thin film is immersed in this solution for 4 hours, and the compound (8) is chemically bonded to the hydroxyl group on the surface of the hydrogel precursor thin film by esterification, and the hydrogel precursor thin film is then bonded to the compound (8). Surface modified. Then, it wash | cleaned with toluene and THF, and obtained the hydrogel precursor thin film (pattern formation body) surface-modified with the compound (8). In order to confirm whether or not the hydrogel precursor thin film was surface-modified with the compound (8), the absorption spectrum of this thin film was examined with a diode array ultraviolet-visible absorption spectroscope (manufactured by Hewlett-Packard Co., product number 8452). However, the absorbance at about 350 nm derived from the trans form of azobenzene was about 0.1 to 0.15. According to the literature (T. Seki et al., Phys. Chem. B, 102, 5313-5321 (1998)), the absorbance of a monomolecular film of a polymer having substantially the same electronic state as that of azobenzene used was 0.015. Its molecular length is about 2 nm. As a rough estimate from this, it is inferred that the prepared pattern formed body is surface-treated with azobenzene in a region of 20 to 40 nm from the surface of the hydrogel precursor thin film.

(4) Confirmation that the surface is modified In order to confirm that the surface of the hydrogel precursor thin film is treated with azobenzene by the compound (8) by the above-described methods (1) to (3), the diameter is about 0. A .5 mm hemispherical hydrogel precursor was prepared, and this hydrogel precursor was treated with azobenzene using the same method as in the above (1) to (3). The treated hydrogel precursor is cut into pieces, and this is converted into 0 of 1,1′-dioctadecyl-3,3,3 ′, 3′-tetramethylindole dicarbocyanine perchloride (Aldrich), which is a hydrophobic fluorescent dye. It was immersed in a 5% acetone solution for 30 minutes and washed with acetone. Then, when the hydrogel precursor was immersed in water and the cross section of the hydrogel precursor was observed in water using the fluorescence microscope (Olympus company make, BX51), fluorescence was shown in the surface layer part. This is considered to be because a hydrophobic part was formed on the surface of the hydrogel precursor by the compound (8), and it was confirmed that azobenzene was modified on the surface of the hydrogel precursor.

(5) Photopatterning with fluorescent fine particles A hydrogel precursor thin film surface-modified with the compound (8), that is, a pattern forming body is immersed in purified water for about 30 minutes, and then an aqueous solution of about 0.01% by weight amine-surface polystyrene fluorescent fine particles. (Molecular probe, trade name Fluorosphere F-8765, particle size of about 1 μm) was immersed for 30 minutes to 1 hour. Subsequently, ultrasonic cleaning was performed in distilled water for 5 to 15 minutes, and the state of the surface of the pattern formed body was observed at a magnification of 10 using a fluorescence microscope (Olympus, BX51). A photomicrograph of the situation at this time is shown in FIG. At this time, the pattern forming body is not irradiated with light. As shown in FIG. 1, it was confirmed that the entire surface of the pattern forming body emitted fluorescence, and amine surface polystyrene fluorescent fine particles were adsorbed on the entire surface of the pattern forming body. Thus, the reason why the fluorescent fine particles were adsorbed on the entire surface of the pattern forming body was that a hydrophobic-hydrophobic interaction occurred between the amino terminus of the fluorescent fine particles that were relatively hydrophobic and the surface of the pattern forming body. Inferred. This suggests that the entire surface of the pattern forming body is hydrophobic. Next, mercury xenon lamp light (ultraviolet light) is passed through a photomask having slits at equal intervals on the pattern forming body in which the fluorescent fine particles are adsorbed and a colored glass filter (manufactured by Toshiba Glass, UV-35 and UVD-36). (Light, wavelength 365 nm) was subjected to pattern exposure at an exposure amount of about 1 J / cm ² (20 mW, 50 seconds). After pattern exposure, the pattern formed body was immersed in distilled water and washed lightly, and the state of the surface of the pattern formed body was observed with a fluorescence microscope at a magnification of 10 times. A photomicrograph of the situation at this time is shown in FIG. As shown in FIG. 2, a photo pattern similar to the photo mask was formed on the surface of the pattern forming body, and it was confirmed that the fluorescent fine particles were detached from the exposed portion. This suggests that the portion irradiated with ultraviolet light has changed from hydrophobic to hydrophilic. Next, mercury xenon lamp light (ultraviolet light, wavelength 365 nm) is applied to the pattern forming body on which the photo pattern is formed through a colored glass filter (Toshiba Glass, UV-35 and UVD-36) at about 1 J / cm ^2. The entire surface was irradiated with an exposure amount (20 mW, 50 seconds). After irradiation, the pattern formed body was immersed in distilled water and washed lightly, and the state of the surface of the pattern formed body was observed with a fluorescence microscope at a magnification of 10 times. A photomicrograph of the situation at this time is shown in FIG. As shown in FIG. 3, a fluorescent image could not be confirmed on the surface of the pattern forming body. This is presumably because the fluorescent fine particles were detached from the pattern forming body due to the surface of the pattern forming body becoming hydrophilic by irradiation with ultraviolet light. Further, mercury xenon lamp light (visible light, wavelength 436 nm) is passed through a colored glass filter (Toshiba Glass, Y-43 and V-44) to the pattern-formed body on which the fluorescent fine particles are not adsorbed at about 1 J / cm ^2. The entire surface was irradiated with an exposure amount of (5 mW, 200 seconds). After the irradiation, the pattern forming body was immersed in purified water for about 30 minutes, and immersed in about 0.01% by weight of amine surface polystyrene fluorescent fine particles for 30 minutes to 1 hour. Subsequently, ultrasonic cleaning was performed in distilled water for 5 to 15 minutes, and the state of the surface of the pattern formed body was observed at a magnification of 10 using a fluorescence microscope. A photomicrograph of the situation is shown in FIG. As shown in FIG. 4, when the visible light was irradiated on the entire surface of the pattern forming body, the fluorescent fine particles were adsorbed on the entire surface of the pattern forming body as in FIG. From this, it is suggested that the surface of the pattern forming body became hydrophobic by irradiation of visible light to the pattern forming body. Further, when this series of operations was repeated, in all cases, the fluorescent fine particles were adsorbed in the exposed portion irradiated with visible light, and the fluorescent fine particles were desorbed in the exposed portion irradiated with ultraviolet light.

(6) Confirmation of the three-dimensional structure of azobenzene In order to confirm the three-dimensional structure of azobenzene when the surface of the pattern forming body is exposed to ultraviolet light and when exposed to visible light, each light is applied to the entire surface of the pattern forming body. The absorption spectrum when irradiated was examined. The result is shown in FIG. As shown in FIG. 5, a wide absorption spectrum having a maximum absorption wavelength of 336 nm was obtained when the pattern-formed body was produced and no light was irradiated and when visible light was irradiated. This spectrum is considered to be attributed to 350 nm, in which the photoisomer accompanying the π-π ^* excitation of azobenzene is shown in a solution state (M. Shimomura et al., Ber. Bunsenges. Phys. Chem., 87, 1134 (1983). ), M. Kasha, Spectroscopy of Exited States p.337 (Plenum press, 1976)). From this, it was confirmed that azobenzene was a trans form when the pattern-formed body was produced and no light was irradiated and when visible light was irradiated. Further, from this result and the result of the photo patterning by the fluorescent fine particles of the above (5), it was confirmed that the surface of the pattern forming body becomes hydrophobic when azobenzene is in the trans form. Note that the maximum absorption wavelength in the pattern-forming body is slightly shifted to a shorter wavelength side than 350 nm because of association between molecules, and a wide range of absorption near this wavelength is due to a mixture of various association states. Presumed to be. On the other hand, when the pattern forming body was irradiated with ultraviolet light, a spectrum showing broad absorption at 450 nm was obtained. This spectrum is considered to belong to the n-π ^* state which is the planar type of azobenzene (Z. Sekkat, W. Knoll, Photoactive Organic Thin Films, p. 3 (Academic Press, 2002), etc.). From this, it was confirmed that azobenzene becomes a cis form when the pattern forming body is irradiated with ultraviolet light. Further, from this result and the result of the photo patterning by the fluorescent fine particles (5) described above, it was confirmed that the surface of the pattern forming body became hydrophilic when azobenzene was a cis body.

  In Example 2, 11- {4-[(4-hexylphenyl) azo] phenoxy} undecane isocyanate (compound of the following formula) was prepared in the same manner as in Example 1 above, and a hydroprecursor thin film was prepared and synthesized by the following method. (See (9)) 40 mg and 0.1 ml of dibutyltin dilaurate were dissolved in 3 ml of dry toluene, and the hydroprecursor thin film was immersed in this solution for 3 to 5 minutes on a hot plate heated to 60 degrees. After soaking, it was washed with toluene and then with THF. This obtained the pattern formation body which is a hydrogel precursor thin film surface-modified with the compound (9). Here, the compound (9) was synthesized as follows. That is, 11- {4-[(4-hexylphenyl) azo] phenoxy} undecanoic acid, diphenylphosphoryl azide and triethylamine synthesized in the same manner as in Example 1 above were heated and refluxed in dry benzene. The reaction was carried out until the starting carboxylic acid disappeared by thin layer chromatography. After the reaction, the solution was concentrated under reduced pressure, and 11- {4-[(4-hexylphenyl) azo] phenoxy} undecane isocyanate of compound (8) was obtained by column chromatography. Photopatterning with fluorescent fine particles was carried out in the same manner as in Example 1 (5) above using the pattern forming body. As a result, pattern formation and repetition characteristics similar to those in Example 1 were obtained.

(1) Preparation of pattern-formed body In Example 3, 11-cinnamoyloxyundecane isocyanate (compound (10) of the following formula) was prepared in the same manner as in Example 1 except that a hydroprecursor thin film was prepared and synthesized by the following method. Reference) 40 mg and 0.1 ml of dibutyltin dilaurate were dissolved in dry toluene, and the hydroprecursor thin film was immersed in this solution for 3 to 5 minutes on a hot plate heated at 60 ° C. under light shielding. After soaking, it was washed with toluene and then with THF. This obtained the pattern formation body which is the hydrogel precursor thin film surface-modified by 11-cinnamoyl oxyundecane isocyanate. Here, the compound (10) was synthesized as follows. That is, first, cinnamoyl chloride (manufactured by Aldrich) and at least two equivalents of 1,12-dodecanediol (manufactured by Tokyo Chemical Industry) are reacted in THF under basic conditions, and the reaction solution is concentrated and mixed with ethyl acetate-chloroform. Recrystallization from a solvent gave 12-cinnamoyloxidedec-1-ol. This was dissolved in a THF-acetone mixed solvent, a small amount of a saturated aqueous solution of sodium hydrogen carbonate was added, 2,2,6,6-tetramethyl-1-piperidinooxy (manufactured by Tokyo Chemical Industry) and sodium bromide were added and stirred. This aqueous solution was bathed in ice, and the above-mentioned 12-cinnamoyl oxide deca-1-ol was gradually added dropwise. The mixture was stirred for several hours in an ice bath and further stirred for several hours at room temperature. After the solvent was distilled off, hydrochloric acid was added and the mixture was extracted with ethyl acetate. This extract was washed with water and brine, and recrystallized with a hexane-ethyl acetate mixed solvent to obtain 11-cinnamoyloxyundecanoic acid. This 11-cinnamoyloxyundecanoic acid, diphenylphosphoryl azide and triethylamine were heated and refluxed in dry benzene, and the reaction was carried out until the starting carboxylic acid disappeared by thin layer chromatography. After the reaction, the solution was concentrated under reduced pressure, and 11-cinnamoyloxyundecane isocyanate of compound (10) was obtained by column chromatography.

(2) Photo-patterning with fluorescent fine particles After immersing the prepared pattern-formed body in purified water for about 30 minutes, a photomask and colored glass filter (made by Toshiba Glass, UV-29) having slits at equal intervals on the surface of the pattern-formed body. ) And pattern exposure of mercury xenon lamp light (ultraviolet light, wavelength 313 nm) at an exposure amount of about 3 J / cm ² (30 mW, 100 seconds). After the irradiation, the patterned product was immersed in an aqueous solution of about 0.01% by weight of amine-surface polystyrene fluorescent fine particles (manufactured by Molecular Probes, trade name: FluoroSphere F-8765, particle size: about 1 μm) for 30 minutes to 1 hour. Then, ultrasonic cleaning was performed in distilled water for 5 to 15 minutes, and the state of the surface of the pattern formed body was observed at a magnification of 10 using a fluorescence microscope (Olympus, BX51). A photomicrograph of the situation is shown in FIG. As shown in FIG. 6, it was confirmed that a negative photo pattern with respect to the photomask was formed on the surface of the pattern forming body, and the fluorescent fine particles were adsorbed on the exposed portion. Thereby, it was confirmed that the exposed part irradiated with ultraviolet light is hydrophobic and the non-exposed part is hydrophilic.

(3) Confirmation of formation of bridge | crosslinking The absorption spectrum when an ultraviolet light was irradiated to the whole surface of a pattern formation body was investigated. The result is shown in FIG. As shown in FIG. 7, an absorption spectrum having a maximum absorption wavelength of 274 nm was obtained when no light was irradiated after the pattern-formed body was produced. This spectrum is considered to be attributed to the absorption of the cinnamoyl group (Gupta et al., Macromolecules, 37, 9211 (2004), etc.). From this, it was confirmed that a cinnamoyl group was present in the pattern formed body when no light was irradiated after the pattern formed body was produced. Further, from this result and the result of the photo patterning by the fluorescent fine particles of (2) above, the surface of the pattern forming body is hydrophilic when the compound (10) as the photoresponsive substance is not cross-linked. It was confirmed that On the other hand, when the pattern forming body was irradiated with ultraviolet light, almost no absorption at 274 nm attributed to the cinnamoyl group was observed. From this, it was confirmed that when the pattern forming body was irradiated with ultraviolet light, the cinnamoyl group almost disappeared and the photocrosslinking proceeded well. Further, from this result and the result of the photo patterning by the fluorescent fine particles (2) described above, the surface of the pattern forming body becomes hydrophobic when a cross-link is formed with the compound (10) as the photoresponsive substance. It was confirmed.

[Comparative Example 1]
In the pattern formation body of Examples 1-3, in order to confirm whether the hydrogel is involved in the change of water wettability of the pattern formation body surface by light irradiation, as a polymer that has azobenzene but is not in a gel state A random copolymer of 10- {4-[(4′-hexylphenyl) azo] phenoxy} decyl acrylate and PME-200 having a copolymerization ratio of about 1: 1 was synthesized by radical polymerization, and this polymer was prepared using toluene as a solvent. A thin film was formed by spin coating on a glass substrate. This thin film was immersed in a solution containing fluorescent fine particles in the same manner as in Example 1 (5), and the surface of this thin film was observed at a magnification of 10 using a fluorescent microscope. However, the fluorescent fine particles were not adsorbed on the thin film. The thin film was irradiated with ultraviolet light through a photomask and then immersed in a solution containing fluorescent fine particles, and the surface of the pattern formed body was observed at a magnification of 10 using a fluorescent microscope. This is shown in FIG. As shown in FIG. 8, a pattern could not be confirmed on the surface of the thin film even when irradiated with ultraviolet light. From these facts, it is presumed that hydrogel plays an important role in changing the wettability of the surface of the pattern-formed bodies of Examples 1 to 3.

[Comparative Example 2]
For the same purpose as in Comparative Example 1, poly 10- {4-[(4′-pentylphenyl) azo] phenoxy} decyl methacrylate was synthesized by radical polymerization, and this polymer was spin-coated on a glass substrate using toluene as a solvent. As a result, a thin film was formed. When this thin film was patterned with fluorescent fine particles in the same manner as in Comparative Example 1, a pattern could not be confirmed on the surface of the thin film, as in Comparative Example 1.

  In addition, this invention is not limited to the above-mentioned Example at all, and as long as it belongs to the technical scope of this invention, it cannot be overemphasized that it can implement with a various aspect.

It is explanatory drawing (drawing substitute photograph) which observed the surface of the pattern formation body in which the compound (8) was surface-modified with the fluorescence microscope. It is explanatory drawing (drawing substitute photograph) which observed the mode that the ultraviolet-ray was irradiated through the photo pattern to the pattern formation body in which the compound (8) was surface-modified. It is explanatory drawing (drawing substitute photograph) which observed the mode that the ultraviolet-ray was irradiated to the whole surface of the pattern formation body in which the compound (8) was surface-modified. It is explanatory drawing (drawing substitute photograph) which observed the mode that the visible light was irradiated to the whole surface of the pattern formation body in which the compound (8) was surface-modified. It is explanatory drawing of the absorption spectrum of the pattern formation body by which the compound (8) was surface-modified. It is explanatory drawing (drawing substitute photograph) which observed the surface of the pattern formation body in which the compound (10) was surface-modified with the fluorescence microscope. It is explanatory drawing of the absorption spectrum of the pattern formation body by which the compound (10) was surface-modified. It is explanatory drawing (drawing substitute photograph) which observed the surface of the thin film with the fluorescence microscope.

Claims (4)

A pattern forming body capable of forming a pattern using a difference in wettability between an exposed portion and a non-exposed portion when irradiated with light,
Hydrogel,
A surface modification part formed by chemically bonding a hydrophobic photoresponsive substance whose association state is changed by light irradiation to the surface of the hydrogel;
With
When the hydrophobic photoresponsive substance is weakly associated with each other, the surface modification part becomes hydrophilic by being covered with the hydrogel when in contact with water, and the hydrophobic photoresponsive substance Are hydrophobically covered with the hydrophobic photoresponsive substance when they are strongly associated with each other,
The hydrophobic photoresponsive substance includes an azobenzene structure in which a cis isomer and a trans isomer are changed by light irradiation. When irradiated with light in a first wavelength range, the azobenzene structure becomes the cis isomer and weakly associates with each other. When the light in the second wavelength range is irradiated, the azobenzene structure becomes a trans form and is a substance that strongly associates with each other.
Pattern forming body. The surface modification unit chemically bonds the hydrophobic photoresponsive substance to the surface of the hydrogel by any one of an ester bond, a urethane bond, an ether bond, an amide bond, an amino bond, and a carbonate bond. Become,
The pattern forming body according to claim 1 . The hydrophobic photoresponsive substance is chemically bonded to the hydrogel through a spacer structure composed of an ethylene oxide unit composed of a linear alkylene chain having 2 to 12 carbon atoms, 1 to 3 ethylene oxides, or a combination thereof. Combined,
The pattern forming body according to claim 1 or 2 . A pattern forming method capable of forming a pattern using a difference in water wettability between an exposed portion and a non-exposed portion when irradiated with light,
To the patterning device according to any one of claims 1 to 3 patterns by partially adsorbing hydrophobic substances or hydrophilic material after providing the exposed portion and the unexposed portion by irradiating light Forming a pattern by desorbing the hydrophobic substance or hydrophilic substance adsorbed on the exposed portion by irradiating a part of the hydrophobic substance or hydrophilic substance and then irradiating a part thereof with light, or After irradiating one of the light in the first and second wavelength ranges to the whole and then adsorbing the hydrophobic substance or hydrophilic substance, the other of the lights in the first and second wavelength ranges A pattern is formed by desorbing a hydrophobic substance or a hydrophilic substance adsorbed on the exposed part after providing an exposed part and a non-exposed part by irradiating a part of the light.
Pattern forming method.