JP2018188633A - Composition for forming cured film, and cured film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cured film having a low coefficient of linear thermal expansion and high extensibility, and a composition for forming the same.SOLUTION: The composition for forming a cured film according to the present invention contains a compound (A) having two or more glycidyl groups and an aromatic ring, a compound (B) having three or more hydroxyl groups, and cellulose nanofibers. The blending ratio of the compound (B) is 11-100 wt.% of the compound (A). The cured film according to the present invention is formed of a cured film of the composition for forming a cured film.SELECTED DRAWING: None

Description

  The present invention relates to a cured film that can be used as a protective film for display device parts such as liquid crystal display devices, plasma display devices, light emitting diode display devices, EL display devices, touch panels, or other functional films, and a composition for forming the same. .

  Functional films used in a wide range of fields including electronics, medicine, food, and building materials have antistatic properties, gas barrier properties, optical properties, thermal properties, and other functionalities. For example, hard coat films used for various displays are required to have scratch resistance, chemical resistance, weather resistance, and the like.

  However, when an attempt is made to use a functional film as a semiconductor substrate, the functional film made of an organic substance has a larger coefficient of thermal expansion than a glass substrate, so that the functional film shrinks after the heating process, and the semiconductor is a substrate. There was a problem of peeling off.

  Usually, when low linear expansion is required for a film made of an organic material, a method of adding cellulose nanofibers to a plastic film material is known (Patent Document 1). According to this method, excellent characteristics such as low linear expansion characteristics can be imparted by adding cellulose nanofibers to the thermoplastic resin. However, in general, a thermoplastic film has lower heat resistance than a curable film, and the film melts when used at a high temperature.

JP, 2006-222745, A

  The present invention has been made in view of such problems, and an object of the present invention is to provide a cured film having a low coefficient of thermal linear expansion at high temperature and high extensibility, and a composition for forming the cured film.

  The composition for forming a cured film according to the present invention contains a compound (A) having two or more glycidyl groups and an aromatic ring, a compound (B) having three or more hydroxyl groups, and cellulose nanofibers, The compounding ratio of the compound (B) is 11 to 100% by weight of the compound (A).

  Moreover, 5-50 weight% of a compound (A) may be sufficient as the mixture ratio of a cellulose nanofiber.

  The composition for forming a cured film according to the present invention includes a compound (A) having two or more glycidyl groups and an aromatic ring, a compound (B) having three or more hydroxyl groups, and two or more alicyclic rings. Compound (C) having an epoxy group and cellulose nanofibers, the compounding amount of compound (C) is 100 parts by weight or less with respect to 100 parts by weight of compound (A), and compounding of compound (B) The ratio is 11 to 100% by weight of the compounds (A) and (C).

  Moreover, 5-50 weight% of a compound (A) may be sufficient as the mixture ratio of a cellulose nanofiber.

  Moreover, the cellulose nanofiber may be quaternary alkylamined.

  Moreover, the cured film which concerns on this invention consists of a cured film of said composition for cured film formation.

Further, the tensile strength of the cured film is 45 N / mm ² or more, the coefficient of thermal expansion at 160 ° C. is 10 × 10 ⁻⁵ / ° C. or less, and the tensile elongation defined by the following formula (I) is It is preferably 4% or more.
Tensile elongation (%) = {(Length at break) − (Initial length before tension)} × 100 / Initial length before tension Formula (I)

  The thickness of the cured film is preferably 10 to 200 μm.

  According to the present invention, a cured film having a low thermal linear expansion coefficient and high extensibility can be realized using a compound containing an aromatic ring and a glycidyl group and cellulose nanofiber as main raw materials.

  Embodiments of the present invention will be described below. The embodiments of the present invention are not limited to the embodiments described below, and modifications such as design changes can be added based on the knowledge of those skilled in the art. Embodiments to which is added can also be included in the scope of the embodiments of the present invention.

  The curable polymer used in the present invention refers to a substance obtained by curing a curable compound through a crosslinking reaction by irradiation with active energy rays such as ultraviolet rays and electron beams and post-heating.

  The cured film according to the present embodiment includes at least a compound (A) having two or more glycidyl groups and an aromatic ring in one molecule, a compound (B) having three or more hydroxyl groups, and cellulose nanofibers. It is obtained by applying the composition containing the composition to a support and curing the composition, and then releasing the curable polymer from the support.

  When a compound having one glycidyl group is used as the compound (A), it is difficult to form a target cured film due to insufficient curing. Further, when a compound having 2 or less hydroxyl groups is used as the compound (B), a film having the desired characteristics cannot be obtained.

  When the compound (A) which is the main raw material of the cured film contains an aromatic ring, it is possible to impart heat resistance and extensibility to the cured film. Since an aromatic ring is a conjugated system and π electrons are delocalized, a polymer containing an aromatic ring is often rigid and excellent in heat resistance. Furthermore, since aromatic rings are bonded to each other by intermolecular force, a cured film having high extensibility can be provided by using a flexibility imparting agent such as compound (B) in combination.

  In addition to the compounds (A), (B) and cellulose nanofibers, a compound having two or more alicyclic epoxy groups in one molecule may be used as the compound (C). When a compound (C) is further mix | blended, reactivity will improve and it will become easy to harden | cure a composition. As a result, it is possible to perform winding without performing post-baking after irradiation with active energy rays. Even when compound (C) is further blended, post-baking after irradiation with active energy rays may be performed. By performing post-baking, the extensibility is further improved.

  When compounding compound (C), the compounding amount of compound (C) is 100 parts by weight or less with respect to 100 parts by weight of compound (A). If this blending amount is not satisfied, it becomes difficult to impart the desired thermal linear expansion coefficient or extensibility.

  The compounding ratio of the compound (B) is 11 to 100% by weight with respect to the compound (A) when the compound (C) is not blended. When the compound (C) is blended, the compounds (A) and ( The total content of C) is 11 to 100% by weight. If this blending ratio is not satisfied, it becomes difficult to impart the desired thermal linear expansion coefficient or extensibility.

  When the compound (C) is not blended, the blending ratio of the cellulose nanofiber is 5 to 50% by weight with respect to the compound (A). When the compound (C) is blended, the compounds (A) and (C) ) To 5 to 50% by weight. When the compounding ratio of the compound (C) is less than 5% by weight, it is difficult to impart the desired thermal linear expansion coefficient or extensibility, and when the compounding ratio of the compound (C) is more than 50% by weight. Since the viscosity of the coating liquid increases, it becomes difficult to form a coating film.

  The compound (A) can be arbitrarily selected from known or commonly used compounds. Among them, those containing an aromatic ring as bisphenol A or bisphenol F are preferable. These compounds may be used as commercial products or can be obtained by introducing an epoxy group into the side chain of the polymer. As commercially available products, for example, as bisphenol A type epoxy resin, jER825, jER827, jER828, jER834, jER1001, jER1002, jER1003, jER1004, jER1007, jER1009, jER1010, jER1055 (manufactured by Mitsubishi Chemical Corporation), EPICLON840 , EPICLON 850, EPICLON 1050, EPICLON 1055 (manufactured by DIC Corporation), etc., and bisphenol F type epoxy resins include jER806, jER807, jER4004P, jER4005P, jER4007P, jER4010P (manufactured by Mitsubishi Chemical Corporation), EPICLON 830 , EPICLON 835 (above, manufactured by DIC Corporation), RE-3035-L (Nippon Kayaku Co., Ltd.) ), And the like.

  The compound (B) can be arbitrarily selected from known or commonly used compounds. Among these, as the compound (B), polyester polyol and polycarbonate polyol are preferable. These compounds may be commercially available products or may be synthesized. Examples of commercially available products include Plaxel 205, Plaxel 205U, Plaxel 208, Plaxel 210, Plaxel 210N, Plaxel 212, Plaxel L212AL, Plaxel 220, Plaxel 220N, Plaxel 220NP1, Plaxel 230, Plaxel 230N, Plaxel 240, Plaxel 303, Plaxel 305, Plaxel 308, Plaxel 309, Plaxel 312, Plaxel 320, Plaxel CD205PL, Plaxel CD210, Plaxel CD210PL (manufactured by Daicel Corporation), Duranol T6002, Duranol T6001, Duranol T5652, Duranol T5651, Duranol T5650J, Duranol T4672 DURANOL T4692, DURANAU G3452 (manufactured by Asahi Kasei Chemicals Co., Ltd.), and the like can be used.

  The compound (C) can be arbitrarily selected from known or commonly used compounds. Of these, the alicyclic epoxy group is preferably a cyclohexene oxide group. These compounds may be commercially available or can be obtained by introducing an alicyclic epoxy group into the side chain of the polymer. Examples of commercially available products include Celoxide 2021P, Celoxide 2081, Celoxide 2000, EPOLEADGT 401 (manufactured by Daicel Chemical Industries, Ltd.), and the like.

[Cellulose nanofibers and production method thereof]
The cellulose nanofibers used in the present embodiment need only have a fiber diameter within the following range, and the adjustment method is not particularly limited. That is, the number average minor axis diameter in the minor axis diameter may be 1 nm or more and 100 nm or less, preferably 2 nm or more and 50 nm or less, more preferably 3 nm or more and 20 nm or less. If the number average minor axis diameter is less than 1 nm, a highly crystalline rigid fine cellulose fiber structure cannot be obtained, and the thermal expansion coefficient becomes insufficient. On the other hand, when the number average minor axis diameter exceeds 100 nm, transparency is impaired and it becomes difficult to obtain good coating surface properties. Further, in the major axis diameter, the number average major axis diameter is preferably 20 nm or more, and more preferably 40 nm or more. If the number average major axis diameter is less than 20 nm, the fiber entanglement effect is insufficient and sufficient ductility cannot be obtained. Further, from the viewpoint of improving the effect of the present invention, the number average major axis diameter is more preferably 10 times or more than the number average minor axis diameter.

  The number average minor axis diameter of cellulose nanofibers is obtained as an average value obtained by measuring the minor axis diameter (minimum diameter) of 100 fibers (cellulose nanofibers) through observation with a transmission electron microscope and atomic force microscope. . On the other hand, the number average major axis diameter of cellulose nanofibers is determined by measuring the major axis diameter (maximum diameter) of 100 fibers (cellulose nanofibers) through transmission electron microscope observation and atomic force microscope observation. Desired.

  The type of cellulose that can be used as a raw material for cellulose nanofibers is not particularly limited. For example, in addition to wood-based natural cellulose, non-wood such as cotton linter, bamboo, hemp, bagasse, kenaf, bacterial cellulose, squirt cellulose, and valonia cellulose Natural cellulose, and regenerated cellulose represented by rayon fiber and cupra fiber can be used. From the viewpoint of easy material procurement, it is preferable to use wood-based natural cellulose as a raw material.

The method for producing cellulose nanofiber is not particularly limited. For example, in addition to mechanical treatment with a grinder, oxidation treatment using N-oxyl compounds such as TEMPO, dilute acid hydrolysis treatment, enzyme treatment, etc. are used in combination with mechanical treatment. Methods for obtaining nanofibers are known. Bacterial cellulose can also be used as the cellulose nanofiber. Furthermore, regenerated cellulose nanofibers obtained by dissolving various natural celluloses in various cellulose solvents and then electrospinning may be used. In particular, in the oxidation reaction using N-oxyl compounds such as TEMPO, -CH ₂ OH at the 6th position of the glucopyranose unit of the cellulose molecular chain on the crystal surface is oxidized with high selectivity, via an aldehyde group. Converted to a carboxy group. Thus, since electrostatic repulsion acts between the cellulose nanofibers having a carboxy group introduced on the crystal surface, cellulose single nanofibers dispersed in microfibril units can be obtained.

  The content of the carboxy group in the cellulose single nanofiber is preferably in the range of 0.1 mmol to 5.0 mmol, and preferably 0.5 mmol to 3.0 mmol, per 1 g of the cellulose single nanofiber. More preferred. When the carboxy group amount is 0.1 mmol / g or more, the dispersion stability is good. When the carboxy group amount is 5.0 mmol / g or less, the crystal structure of the cellulose single nanofiber is sufficiently retained, and the thermal expansion coefficient of the cured film to be produced is good.

  Hereinafter, an example of a method for preparing a dispersion of cellulose single nanofibers having a carboxy group introduced by an oxidation reaction using an N-oxyl compound from wood-based natural cellulose will be described. It is not limited to the method. The adjustment method of this example includes a step of oxidizing wood-based natural cellulose with an N-oxyl compound to obtain oxidized cellulose (oxidation step), a step of ammonium chlorinating the carboxyl group of oxidized cellulose (ammonium chloride step), And a step of refining the oxidized cellulose in an aqueous medium to prepare a cellulose single nanofiber dispersion (a refining step).

[Oxidation process of cellulose nanofiber]
The wood-based natural cellulose is not particularly limited, and those generally used for producing cellulose nanofibers such as softwood pulp, hardwood pulp, and waste paper pulp can be used. Softwood pulp is preferred because it is easily refined and refined. Examples of N-oxyl compounds include TEMPO (2,2,6,6-tetramethylpiperidinyl-1-oxy radical), 2,2,6,6-tetramethyl-4-hydroxypiperidine-1-oxyl, 4 -Methoxy-2,2,6,6-tetramethylpiperidine-N-oxyl, 4-ethoxy-2,2,6,6-tetramethylpiperidine-N-oxyl, 4-acetamido-2,2,6,6 -Tetramethylpiperidine-N-oxyl and the like. Among these, TEMPO is preferable. The amount of the N-oxyl compound used is not particularly limited, and may be an amount as a catalyst. Usually, it is about 0.01-5.0 mass% with respect to solid content of the wood type natural cellulose to oxidize.

  Examples of the oxidation method using an N-oxyl compound include a method in which wood-based natural cellulose is dispersed in water and oxidized in the presence of the N-oxyl compound. At this time, it is preferable to use a co-oxidant together with the N-oxyl compound. In this case, in the reaction system, the N-oxyl compound is sequentially oxidized by a co-oxidant to produce an oxoammonium salt, and cellulose is oxidized by the oxoammonium salt. According to such oxidation treatment, the oxidation reaction proceeds smoothly even under mild conditions, and the introduction efficiency of the carboxy group is improved. When the oxidation treatment is performed under mild conditions, it is easy to maintain the crystal structure of cellulose. As the above-mentioned co-oxidant, halogen, hypohalous acid, halous acid, perhalogen acid, or salts thereof, halogen oxide, nitrogen oxide, peroxide, etc. should be able to promote the oxidation reaction. Any oxidizing agent can be used. Sodium hypochlorite is preferred because of its availability and reactivity. The amount of the co-oxidant used is not particularly limited, and may be an amount that can promote the oxidation reaction. Usually, it is about 1-200 mass% with respect to solid content of the wood type natural cellulose to oxidize.

  Along with the N-oxyl compound and the co-oxidant, at least one compound selected from the group consisting of bromide and iodide may be further used in combination. Thereby, an oxidation reaction can be advanced smoothly and the introduction efficiency of a carboxyl group can be improved. As the compound, sodium bromide or lithium bromide is preferable, and sodium bromide is more preferable from the viewpoint of cost and stability. The amount of the compound used is not particularly limited, and may be an amount that can promote the oxidation reaction. Usually, it is about 1-50 mass% with respect to solid content of the wood type natural cellulose to oxidize.

  The reaction temperature of the oxidation reaction is preferably 4 to 50 ° C, more preferably 10 to 40 ° C. When the reaction temperature is less than 4 ° C., the reactivity of the reagent is lowered and the reaction time is prolonged. On the other hand, when the reaction temperature exceeds 50 ° C., the side reaction is promoted to lower the molecular weight of the sample and cause a decrease in viscosity. The reaction time of the oxidation treatment can be appropriately set in consideration of the reaction temperature, the desired amount of carboxy group, and the like, and is not particularly limited, but is usually about 1 to 5 hours.

  The pH of the reaction system during the oxidation reaction is preferably 9-11. When the pH is 9 or more, the reaction can be efficiently carried out. If the pH exceeds 11, side reactions may progress and the decomposition of the sample may be accelerated. In the above oxidation treatment, as the oxidation proceeds, the pH in the system decreases due to the formation of a carboxy group, and therefore the pH of the reaction system is preferably maintained at 9 to 11 during the oxidation treatment. Examples of a method for maintaining the pH of the reaction system at 9 to 11 include a method of adding an alkaline aqueous solution in accordance with a decrease in pH. Examples of alkaline aqueous solutions include sodium hydroxide aqueous solution, lithium hydroxide aqueous solution, potassium hydroxide aqueous solution, ammonia aqueous solution, tetramethylammonium hydroxide aqueous solution, tetraethylammonium hydroxide aqueous solution, tetrabutylammonium hydroxide aqueous solution, benzyltrimethylammonium hydroxide aqueous solution, etc. Organic alkalis, and the like.

  The oxidation reaction with the N-oxyl compound can be stopped by adding alcohol to the reaction system. At this time, the pH of the reaction system is preferably maintained at 9-11. The alcohol to be added is preferably a low molecular weight alcohol such as methanol, ethanol or propanol in order to quickly terminate the reaction, and ethanol is particularly preferred from the viewpoint of the safety of by-products produced by the reaction.

  In the reaction solution after the oxidation treatment, the catalyst such as the N-oxyl compound, impurities, and the like are removed, and then the oxidized cellulose contained in the reaction solution is recovered, and the recovered oxidized cellulose is washed with a cleaning solution. Oxidized cellulose can be collected by a known method such as filtration using a glass filter or a nylon mesh having a 20 μm pore size. In addition, as a cleaning liquid used for cleaning oxidized cellulose, it is preferable to wash in order of hydrochloric acid and distilled water in order to once acidify the alkalized carboxyl group when controlling the pH during the oxidation reaction.

[Ammonium chloride step of cellulose nanofiber]
Thereafter, in order to increase the affinity between the produced cellulose single nanofibers and the above-mentioned compounds (A) to (C), the recovered cellulose nanofibers are dispersed in distilled water or the like, and then a quaternary alkyl ammonium salt is added. . Examples of the quaternary alkylammonium salt at this time include monoalkyltrimethylammonium salt, dialkyldimethylammonium salt, trialkylmonomethylammonium salt, and alkylbenzyldimethylammonium salt, but are not particularly limited.

  In general, cellulose nanofibers are difficult to mix with hydrophobic resins and become cloudy, but by using quaternary alkylamine cellulose nanofibers, the above compounds (A) to (C) are mixed without clouding. To do. Moreover, the cured film excellent in transparency can be provided by using the cellulose nanofiber by which the quaternary alkylamine was carried out. Further, as a secondary effect, it is possible to impart antistatic properties to the cured film by adding a quaternary alkylamine.

[Refining process of cellulose nanofiber]
Subsequently, the cellulose nanofiber dispersion is subjected to a physical fibrillation treatment to refine the oxidized cellulose. For physical fibrillation treatment, high pressure homogenizer, ultra high pressure homogenizer, ball mill, roll mill, cutter mill, planetary mill, jet mill, attritor, grinder, juicer mixer, homomixer, ultrasonic homogenizer, nanogenizer, underwater facing collision, etc. Mechanical treatment is mentioned. By performing such a physical fibrillation treatment, the oxidized cellulose in the suspension is refined, and a dispersion of cellulose single nanofibers having a carboxy group on the fiber surface can be obtained. The number average minor axis diameter and number average major axis diameter of the cellulose single nanofibers contained in the obtained cellulose single nanofiber dispersion liquid can be adjusted by the time and number of times of physical fibrillation treatment at this time.

  The dispersion of cellulose single nanofibers thus refined is mixed with the above-mentioned compounds (A) to (C) and a photoacid generator to complete a composition for forming a cured film.

  Or after following the ammonium chloride step and the refinement step as described above and performing the oxidation step, the above-mentioned compounds (A) to (C), a quaternary ammonium salt, and a photoacid generator are added, You may perform a physical defibration process. The number average minor axis diameter and number average major axis diameter of the cellulose single nanofiber can be adjusted depending on the treatment conditions.

  The photoacid generator is added to react the composition by ultraviolet irradiation. Any photoacid generator may be used as long as it generates cations when irradiated with ultraviolet rays. Examples of commercially available products include CPI-101A, CPI-100P, CPI-200K, and CPI-210S (hereinafter referred to as “San-Apro”). Etc.).

  The amount of the photoacid generator used is preferably 0.03 to 3% by weight based on the total of the compounds (A) and (C). If the amount is larger than this range, the tensile strength tends to decrease. is there. In particular, if the amount is too large, the cured polymer may be colored. When the amount is small, tackiness due to insufficient curing occurs.

  Further, the solvent contained in the composition forming the curable polymer is appropriately selected in consideration of coating suitability and the like from acetone or methyl ethyl ketone which is a ketone solvent having good compatibility with the compound.

  In the prepared composition, an additive can be used for antifouling property, slipperiness imparting, defect prevention and particle dispersibility improvement. Examples of the additive include polyether-modified polymethylalkylsiloxane, polyether-modified polydimethylsiloxane, fluorine-modified polymer, and epoxy copolymer.

  To the prepared composition, fine particles of an inorganic or organic compound can be added for the purpose of providing an antiblocking agent, imparting hardness, imparting antiglare properties, antistatic performance, or adjusting the refractive index.

  Inorganic fine particles added to the prepared composition include oxides such as silicon oxide, titanium oxide, aluminum oxide, zirconium oxide, magnesium oxide, tin oxide, and antimony pentoxide, and composite oxides such as antimony-doped tin oxide and phosphorus-doped tin oxide. In addition, calcium carbonate, talc, clay, kaolin, calcium silicate, aluminum silicate, magnesium silicate, calcium phosphate and the like can be used.

  The organic fine particles include polymethyl methacrylate acrylate resin powder, acrylic-styrene resin powder, polymethyl methacrylate resin powder, silicone resin powder, polystyrene powder, polycarbonate powder, melamine resin powder, polyolefin resin powder, etc. Can be mentioned.

  The average particle size of the inorganic or organic fine particles is preferably 5 nm to 20 μm, more preferably 10 nm to 10 μm. These fine particles can be used in combination of two or more.

  The composition can be applied to a plastic substrate film by dissolving in a solvent and adjusting the solid content to 40 to 100% by mass, more preferably 60 to 95% by mass. When the solid content is less than 40% by mass, it is difficult to obtain a target film thickness.

The light source for curing the composition and forming the cured film can be used without limitation as long as it is a light source that generates ultraviolet rays. For example, a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, a carbon arc lamp, a metal halide lamp, a xenon lamp, an electrodeless discharge tube, or the like can be used. As irradiation conditions, the ultraviolet irradiation amount is usually 100 to 500 mJ / cm ² .

  The curable polymer is completed by sufficiently mixing the above materials, coating, drying, and UV-exposing the substrate, followed by heat treatment.

  When the curable polymer is post-baked, the heating temperature is preferably 60 to 150 ° C. When the heating temperature is less than 60 ° C., it may be difficult to form a cured film due to insufficient curing. When the heating temperature exceeds 150 ° C., the cured film may turn brown.

  When post-baking the above curable polymer, the heating time is preferably 10 minutes or longer so as not to be insufficiently cured, and preferably 60 minutes or shorter so that deterioration due to heat does not occur.

  Then, the cured film is completed by peeling the cured curable polymer from the substrate.

  The thickness of the cured film is preferably 10 μm or more and 200 μm or less. When the thickness of the cured film is less than 10 μm, the handleability of the cured film is deteriorated because it is too thin. On the other hand, when the thickness of the cured film exceeds 200 μm, the cured film is difficult to be cured.

  A wet coating method can be used as a method for applying the composition to the substrate. Examples of wet coating methods include dip coating, spin coating, flow coating, spray coating, roll coating, gravure roll coating, air doctor coating, blade coating, wire doctor coating, knife coating, Examples thereof include a reverse coating method, a transfer roll coating method, a micro gravure coating method, a kiss coating method, a cast coating method, a slot orifice coating method, a calendar coating method, and a die coating method.

  Hereinafter, examples will be described. However, the present invention is not limited to the following examples.

〔Evaluation method〕
The following evaluation tests were implemented about the cured film obtained by the Example and the comparative example.

<Tensile properties>
The tensile properties of the substrate were examined by the following method. First, the cured film was cut into a size of 100 mm (MD direction) × 15 mm (TD direction) to obtain a strip-shaped sample. About this sample, the measurement using the Shimadzu Corporation small desktop testing machine EZ-L was performed. Here, the distance between chucks at the start of measurement was 50 mm, and the tensile speed was 5 mm / min. And tensile elongation was computed using the said formula (I).

<Heat expansion coefficient>
The thermal linear expansion coefficient of the substrate was examined by the following method. First, the cured film was cut into a size of 250 mm (MD direction) × about 4 mm (TD direction) to obtain a strip-shaped sample. About this sample, the measurement using Hitachi high-tech TMA SII EXSTAR6000 TMASS6100 was performed. Here, the load at the time of measurement was 25 mN, the temperature was increased at a rate of 2 ° C./min, and the thermal linear expansion coefficient from 155 ° C. to 165 ° C. was calculated from the temperature-displacement curve.

In the following Examples and Comparative Examples, the following compounds were used.
Compound (A): “jER828 (Mitsubishi Chemical Corporation)”
Compound (B): “Placcel 305 (polycaprolactone triol, manufactured by Daicel Chemical Industries, Ltd.)”
Compound (C): “Celoxide 2021P (3 ′, 4′-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, manufactured by Daicel Chemical Industries, Ltd.)
Photo acid generator: “CPI-210S (manufactured by Sun Apro)” “CPI-110A (manufactured by Sun Apro)”
・ Cellulose: Softwood kraft pulp ・ Quaternary alkylamination reagent: “Dimethylaminopropylacrylamide methyl chloride quaternary salt (manufactured by Kojinsha)”

Cellulose nanofibers used in the following examples and comparative examples were prepared as follows.
-TEMPO oxidation of wood cellulose:
70 g of softwood kraft pulp was suspended in 3500 g of distilled water, and a solution of 0.7 g of TEMPO and 7 g of sodium bromide dissolved in 350 g of distilled water was added and cooled to 20 ° C. 450 g of sodium hypochlorite aqueous solution having a concentration of 2 mol / L and a density of 1.15 g / mL was added dropwise thereto to initiate an oxidation reaction. The temperature in the system was always kept at 20 ° C., and the decrease in pH during the reaction was kept at pH 10 by adding a 0.5N aqueous sodium hydroxide solution. When sodium hydroxide reached 3.00 mmol / g based on the mass of cellulose, an excessive amount of ethanol was added to stop the reaction. Then, it wash | cleaned with 1 mol / L hydrochloric acid using the glass filter, the filtration washing | cleaning by distilled water was repeated, and the oxidized pulp was obtained.

[Example 1]
<Preparation of composition>
After mixing the compounds (A), (B), photoacid generator, and oxidized pulp at the following blending ratio (unit: parts by weight), the mixture is dispersed in methyl ethyl ketone using a planetary ball mill, and removed by applying ultrasonic waves. A composition was obtained by foaming.
jER828 100.0 parts by weight Plaxel 305 25.0 parts by weight CPI-210S 1.0 part by weight oxidized pulp 5.0 parts by weight

<Preparation of curable polymer>
The composition obtained by preparing the composition (diluted with methyl ethyl ketone) was applied to Lumirror T60 (thickness 75 μm; manufactured by Toray Industries, Inc.), which is a PET film, by a bar coating method so that the cured film thickness becomes 45 μm. The coating film was dried in an oven at 80 ° C. for 2 minutes and 40 seconds, and then irradiated with 300 mJ / cm ² ultraviolet rays by a high-pressure mercury lamp. Then, a curable polymer was obtained through post-baking at 120 ° C. for 20 minutes.

<Production of cured film>
The curable polymer was peeled from the PET film to obtain a cured film. The obtained cured film was a cured film having good properties with a tensile strength of 70 N / mm ² , a tensile elongation of 5%, and a thermal linear expansion coefficient of 6 × 10 ⁻⁵ / ° C.

[Example 2]
jER828 100.0 parts by weight Plaxel 305 11.1 parts by weight CPI-210S 1.0 part by weight oxidized pulp 5.0 parts by weight dimethylaminopropylacrylamide methyl chloride quaternary salt 1.0 parts by weight And dispersed in methyl ethyl ketone. After defoaming the composition by applying ultrasonic waves, it was applied on a PET film so that the cured film thickness was 45 μm. After the applied composition (diluted with methyl ethyl ketone) is dried in an oven (80 ° C., 2 minutes and 40 seconds), the curable polymer obtained by UV irradiation and post-baking (120 ° C., 10 minutes) is peeled off from the PET film. Thus, a cured film was obtained. The obtained cured film was a cured film with good properties having a tensile strength of 70 N / mm ² , a tensile elongation of 7%, and a thermal linear expansion coefficient of 6 × 10 ⁻⁵ / ° C.

Example 3
jER828 100.0 parts by weight Plaxel 305 25.0 parts by weight CPI-210S 1.0 part by weight oxidized pulp 5.0 parts by weight dimethylaminopropylacrylamide methyl chloride quaternary salt 1.0 parts by weight And dispersed in methyl ethyl ketone. After defoaming the composition by applying ultrasonic waves, it was applied on a PET film so that the cured film thickness was 45 μm. After the applied composition (diluted with methyl ethyl ketone) is dried in an oven (80 ° C., 2 minutes and 40 seconds), the curable polymer obtained by UV irradiation and post-baking (120 ° C., 10 minutes) is peeled off from the PET film. Thus, a cured film was obtained. The obtained cured film was a cured film with good properties having a tensile strength of 75 N / mm ² , a tensile elongation of 4%, and a thermal linear expansion coefficient of 4 × 10 ⁻⁵ / ° C.

Example 4
jER828 100.0 parts by weight Plaxel 305 100.0 parts by weight CPI-210S 1.0 part by weight oxidized pulp 5.0 parts by weight dimethylaminopropylacrylamide methyl chloride quaternary salt 1.0 parts by weight And dispersed in methyl ethyl ketone. After defoaming the composition by applying ultrasonic waves, it was applied on a PET film so that the cured film thickness was 45 μm. After the applied composition (diluted with methyl ethyl ketone) is dried in an oven (80 ° C., 2 minutes 40 seconds), the curable polymer obtained by UV irradiation and post-baking (120 ° C., 20 minutes) is peeled off from the PET film. Thus, a cured film was obtained. The obtained cured film was a cured film with good properties having a tensile strength of 50 N / mm ² , a tensile elongation of 10%, and a thermal linear expansion coefficient of 9 × 10 ⁻⁵ / ° C.

Example 5
jER828 100.0 parts by weight Plaxel 305 25.0 parts by weight CPI-210S 1.0 part by weight oxidized pulp 50.0 parts by weight dimethylaminopropylacrylamide methyl chloride quaternary salt 10.0 parts by weight And dispersed in methyl ethyl ketone. After defoaming the composition by applying ultrasonic waves, it was applied on a PET film so that the cured film thickness was 45 μm. After the applied composition (diluted with methyl ethyl ketone) is dried in an oven (80 ° C., 2 minutes and 40 seconds), the curable polymer obtained by UV irradiation and post-baking (120 ° C., 10 minutes) is peeled off from the PET film. Thus, a cured film was obtained. The obtained cured film was a cured film with good characteristics having a tensile strength of 80 N / mm ² , a tensile elongation of 4%, and a thermal linear expansion coefficient of 1 × 10 ⁻⁵ / ° C.

Example 6
jER828 100.0 parts by weight Plaxel 305 100.0 parts by weight CPI-210S 1.0 part by weight oxidized pulp 50.0 parts by weight dimethylaminopropylacrylamide methyl chloride quaternary salt 10.0 parts by weight And dispersed in methyl ethyl ketone. After defoaming the composition by applying ultrasonic waves, it was applied on a PET film so that the cured film thickness was 45 μm. After the applied composition (diluted with methyl ethyl ketone) is dried in an oven (80 ° C., 2 minutes 40 seconds), the curable polymer obtained by UV irradiation and post-baking (120 ° C., 20 minutes) is peeled off from the PET film. Thus, a cured film was obtained. The obtained cured film was a cured film with good properties having a tensile strength of 60 N / mm ² , a tensile elongation of 4%, and a thermal linear expansion coefficient of 4 × 10 ⁻⁵ / ° C.

Example 7
jER828 90.0 parts by weight Plaxel 305 25.0 parts by weight Celoxide 2021P 10.0 parts by weight CPI-110A 0.03 parts by weight oxidized pulp 5.0 parts by weight dimethylaminopropylacrylamide methyl chloride quaternary salt 1.0 part by weight After mixing, it was dispersed in methyl ethyl ketone using a planetary ball mill. After defoaming the composition by applying ultrasonic waves, it was applied on a PET film so that the cured film thickness was 45 μm. After the applied composition (diluted with methyl ethyl ketone) is dried in an oven (80 ° C., 2 minutes 40 seconds), the curable polymer obtained by UV irradiation and post-baking (120 ° C., 20 minutes) is peeled off from the PET film. Thus, a cured film was obtained. The obtained cured film was a cured film with good properties having a tensile strength of 55 N / mm ² , a tensile elongation of 10%, and a thermal linear expansion coefficient of 5 × 10 ⁻⁵ / ° C.

Example 8
jER828 80.0 parts by weight Plaxel 305 25.0 parts by weight Celoxide 2021P 20.0 parts by weight CPI-110A 0.03 parts by weight oxidized pulp 5.0 parts by weight dimethylaminopropylacrylamide methyl chloride quaternary salt 1.0 part by weight After mixing, it was dispersed in methyl ethyl ketone using a planetary ball mill. After defoaming the composition by applying ultrasonic waves, it was applied on a PET film so that the cured film thickness was 45 μm. After the applied composition (diluted with methyl ethyl ketone) is dried in an oven (80 ° C., 2 minutes 40 seconds), the curable polymer obtained by UV irradiation and post-baking (120 ° C., 20 minutes) is peeled off from the PET film. Thus, a cured film was obtained. The obtained cured film was a cured film with good properties having a tensile strength of 65 N / mm ² , a tensile elongation of 10%, and a thermal linear expansion coefficient of 6 × 10 ⁻⁵ / ° C.

Example 9
jER828 50.0 parts by weight Plaxel 305 25.0 parts by weight Celoxide 2021P 50.0 parts by weight CPI-110A 0.03 parts by weight oxidized pulp 5.0 parts by weight dimethylaminopropylacrylamide methyl chloride quaternary salt 1.0 part by weight After mixing, it was dispersed in methyl ethyl ketone using a planetary ball mill. After defoaming the composition by applying ultrasonic waves, it was applied on a PET film so that the cured film thickness was 45 μm. After the applied composition (diluted with methyl ethyl ketone) is dried in an oven (80 ° C., 2 minutes 40 seconds), the curable polymer obtained by UV irradiation and post-baking (120 ° C., 20 minutes) is peeled off from the PET film. Thus, a cured film was obtained. The obtained cured film was a cured film with good properties having a tensile strength of 50 N / mm ² , a tensile elongation of 5%, and a thermal linear expansion coefficient of 8 × 10 ⁻⁵ / ° C.

Example 10
jER828 90.0 parts by weight Plaxel 305 11.1 parts by weight Celoxide 2021P 10.0 parts by weight CPI-210S 1.0 part by weight oxidized pulp 50.0 parts by weight dimethylaminopropylacrylamide methyl chloride quaternary salt 10.0 parts by weight After mixing, it was dispersed in methyl ethyl ketone using a planetary ball mill. After defoaming the composition by applying ultrasonic waves, it was applied on a PET film so that the cured film thickness was 45 μm. After the applied composition (diluted with methyl ethyl ketone) is dried in an oven (80 ° C., 2 minutes 40 seconds), the curable polymer obtained by UV irradiation and post-baking (120 ° C., 20 minutes) is peeled off from the PET film. Thus, a cured film was obtained. The obtained cured film was a cured film with good properties having a tensile strength of 60 N / mm ² , a tensile elongation of 6%, and a thermal linear expansion coefficient of 2 × 10 ⁻⁵ / ° C.

Example 11
jER828 50.0 parts by weight Plaxel 305 11.1 parts by weight Celoxide 2021P 50.0 parts by weight CPI-210S 1.0 part by weight oxidized pulp 50.0 parts by weight dimethylaminopropylacrylamide methyl chloride quaternary salt 10.0 parts by weight After mixing, it was dispersed in methyl ethyl ketone using a planetary ball mill. After defoaming the composition by applying ultrasonic waves, it was applied on a PET film so that the cured film thickness was 45 μm. After the applied composition (diluted with methyl ethyl ketone) is dried in an oven (80 ° C., 2 minutes and 40 seconds), the curable polymer obtained by UV irradiation and post-baking (120 ° C., 10 minutes) is peeled off from the PET film. Thus, a cured film was obtained. The obtained cured film was a cured film with good characteristics having a tensile strength of 70 N / mm ² , a tensile elongation of 4%, and a thermal linear expansion coefficient of 5 × 10 ⁻⁵ / ° C.

Example 12
jER828 90.0 parts by weight Plaxel 305 100.0 parts by weight Celoxide 2021P 10.0 parts by weight CPI-210S 1.0 part by weight oxidized pulp 50.0 parts by weight dimethylaminopropylacrylamide methyl chloride quaternary salt 10.0 parts by weight After mixing, it was dispersed in methyl ethyl ketone using a planetary ball mill. After defoaming the composition by applying ultrasonic waves, it was applied on a PET film so that the cured film thickness was 45 μm. After the applied composition (diluted with methyl ethyl ketone) is dried in an oven (80 ° C., 2 minutes 40 seconds), the curable polymer obtained by UV irradiation and post-baking (120 ° C., 20 minutes) is peeled off from the PET film. Thus, a cured film was obtained. The obtained cured film was a cured film with good properties having a tensile strength of 45 N / mm ² , a tensile elongation of 20%, and a thermal linear expansion coefficient of 4 × 10 ⁻⁵ / ° C.

Example 13
jER828 50.0 parts by weight Plaxel 305 100.0 parts by weight Celoxide 2021P 50.0 parts by weight CPI-210S 1.0 part by weight oxidized pulp 50.0 parts by weight dimethylaminopropylacrylamide methyl chloride quaternary salt 10.0 parts by weight After mixing, it was dispersed in methyl ethyl ketone using a planetary ball mill. After defoaming the composition by applying ultrasonic waves, it was applied on a PET film so that the cured film thickness was 45 μm. After the applied composition (diluted with methyl ethyl ketone) is dried in an oven (80 ° C., 2 minutes and 40 seconds), the curable polymer obtained by UV irradiation and post-baking (120 ° C., 10 minutes) is peeled off from the PET film. Thus, a cured film was obtained. The obtained cured film was a cured film with good properties having a tensile strength of 50 N / mm ² , a tensile elongation of 15%, and a thermal linear expansion coefficient of 7 × 10 ⁻⁵ / ° C.

Example 14
jER828 50.0 parts by weight Plaxel 305 11.1 parts by weight Celoxide 2021P 50.0 parts by weight CPI-210S 1.0 part by weight oxidized pulp 5.0 parts by weight dimethylaminopropylacrylamide methyl chloride quaternary salt 1.0 part by weight After mixing, it was dispersed in methyl ethyl ketone using a planetary ball mill. After defoaming the composition by applying ultrasonic waves, it was applied on a PET film so that the cured film thickness was 45 μm. The applied composition (diluted with methyl ethyl ketone) was dried in an oven (80 ° C., 2 minutes 40 seconds), and then the curable polymer obtained by UV irradiation was peeled off from the PET film to obtain a cured film. The obtained cured film was a cured film with good properties having a tensile strength of 55 N / mm ² , a tensile elongation of 4%, and a thermal linear expansion coefficient of 9 × 10 ⁻⁵ / ° C.

Example 15
jER828 100.0 parts by weight Plaxel 305 25.0 parts by weight CPI-210S 1.0 part by weight oxidized pulp 5.0 parts by weight dimethylaminopropylacrylamide methyl chloride quaternary salt 1.0 parts by weight And dispersed in methyl ethyl ketone. After defoaming the composition by applying ultrasonic waves, it was applied on a PET film so that the cured film thickness was 10 μm. After the applied composition (diluted with methyl ethyl ketone) is dried in an oven (80 ° C., 2 minutes and 40 seconds), the curable polymer obtained by UV irradiation and post-baking (120 ° C., 10 minutes) is peeled off from the PET film. Thus, a cured film was obtained. The obtained cured film was a cured film with good characteristics having a tensile strength of 55 N / mm ² , a tensile elongation of 7%, and a thermal linear expansion coefficient of 4 × 10 ⁻⁵ / ° C.

Example 16
jER828 100.0 parts by weight Plaxel 305 25.0 parts by weight CPI-210S 1.0 part by weight oxidized pulp 5.0 parts by weight dimethylaminopropylacrylamide methyl chloride quaternary salt 1.0 parts by weight And dispersed in methyl ethyl ketone. After defoaming the composition by applying ultrasonic waves, it was applied on a PET film so that the cured film thickness was 200 μm. After the applied composition (diluted with methyl ethyl ketone) is dried in an oven (80 ° C., 2 minutes and 40 seconds), the curable polymer obtained by UV irradiation and post-baking (120 ° C. and 60 minutes) is peeled off from the PET film. Thus, a cured film was obtained. The obtained cured film was a cured film with good properties having a tensile strength of 60 N / mm ² , a tensile elongation of 10%, and a thermal linear expansion coefficient of 6 × 10 ⁻⁵ / ° C.

[Comparative Example 1]
jER828 100.0 parts by weight Plaxel 305 25.0 parts by weight CPI-210S 1.0 parts by weight were mixed and then dispersed in methyl ethyl ketone. After defoaming the composition by applying ultrasonic waves, it was applied on a PET film so that the cured film thickness was 45 μm. After the applied composition (diluted with methyl ethyl ketone) is dried in an oven (80 ° C., 2 minutes and 40 seconds), the curable polymer obtained by UV irradiation and post-baking (120 ° C., 10 minutes) is peeled off from the PET film. Thus, a cured film was obtained. The obtained cured film was a cured film having high thermal linear expansion and low tensile strength, having a tensile strength of 40 N / mm ² , a tensile elongation of 15%, and a thermal expansion coefficient of 28 × 10 ⁻⁵ / ° C.

[Comparative Example 2]
jER828 80.0 parts by weight Plaxel 305 25.0 parts by weight Celoxide 2021P 20.0 parts by weight CPI-210S 1.0 parts by weight were mixed and then dispersed in methyl ethyl ketone. After defoaming the composition by applying ultrasonic waves, it was applied on a PET film so that the cured film thickness was 45 μm. After the applied composition (diluted with methyl ethyl ketone) is dried in an oven (80 ° C., 2 minutes and 40 seconds), the curable polymer obtained by UV irradiation and post-baking (120 ° C., 10 minutes) is peeled off from the PET film. Thus, a cured film was obtained. The obtained cured film was a high thermal linear expansion cured film having a tensile strength of 55 N / mm ² , a tensile elongation of 15%, and a thermal expansion coefficient of 24 × 10 ⁻⁵ / ° C.

  Table 1 summarizes the compositions, film forming conditions, and evaluation results of the compositions according to Examples 1 to 16 and Comparative Examples 1 and 2 described above.

  INDUSTRIAL APPLICABILITY The present invention can be used as a protective substrate for display devices such as semiconductor substrates and touch panels that require low linear expansion characteristics, and as a substrate for other functional films.

Claims (8)

Containing a compound (A) having two or more glycidyl groups and an aromatic ring, a compound (B) having three or more hydroxyl groups, and cellulose nanofibers;
The composition for cured film formation whose compounding ratio of the said compound (B) is 11 to 100 weight% of the said compound (A).   The composition for forming a cured film according to claim 1, wherein the blending ratio of the cellulose nanofiber is 5 to 50% by weight of the compound (A). A compound (A) having two or more glycidyl groups and an aromatic ring, a compound (B) having three or more hydroxyl groups, a compound (C) having two or more alicyclic epoxy groups, cellulose nanofibers, Containing
The compounding amount of the compound (C) is 100 parts by weight or less with respect to 100 parts by weight of the compound (A),
The composition for cured film formation whose compounding ratio of the said compound (B) is 11 to 100 weight% of the said compounds (A) and (C).   The composition for forming a cured film according to claim 3, wherein the blending ratio of the cellulose nanofiber is 5 to 50% by weight of the compounds (A) and (C).   The composition for forming a cured film according to claim 1, wherein the cellulose nanofiber is quaternary alkylamined.   The cured film which consists of a cured film of the composition for cured film formation in any one of Claims 1-5. The cured film has a tensile strength of 45 N / mm ² or more, a thermal linear expansion coefficient at 160 ° C. of 10 × 10 ⁻⁵ / ° C. or less, and a tensile elongation defined by the following formula (I) of 4 The cured film according to claim 6, which is at least%.
Tensile elongation (%) = {(Length at break) − (Initial length before tension)} × 100 / Initial length before tension Formula (I)   The cured film according to claim 6 or 7, wherein the cured film has a thickness of 10 to 200 µm.