JP2009161896A - Cellulose nonwoven fabric, process for manufacturing the same and composite material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cellulose nonwoven fabric which imparts a composite material with high transparency, non-coloring properties and small coefficient of linear expansion by controlling porosity and chemical modification rate. <P>SOLUTION: The cellulose nonwoven fabric is a nonwoven fabric of a chemically modified cellulose with 8-65 mol.% of chemical modification rate to the total hydroxyl group and having at least 35 vol.%, preferably 35-60 vol.% of porosity. The cellulose nonwoven fabric is obtained by forming a cellulose nonwoven fabric and then subjecting to a chemical modification. The composite material comprises the cellulose nonwoven fabric and a resin excluding cellulose. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a cellulose nonwoven fabric and a method for producing the same, and a composite material using the cellulose nonwoven fabric, and in particular, by controlling the porosity and chemical modification rate of the cellulose nonwoven fabric, it has high transparency when formed into a composite material. The present invention relates to a technique for realizing non-coloring properties and a low linear expansion coefficient.

  In recent years, composite materials using fine cellulose fibers such as bacterial cellulose have been studied extensively. It is known that cellulose exhibits a low linear expansion coefficient, a high elastic modulus, and a high strength because of its extended chain crystal. In addition, it has been attracting attention as a material exhibiting high transparency when made into a composite material by miniaturization.

  In Patent Document 1, a cellulose composite material is obtained by using bacterial cellulose or wood as a raw material, dried from a hydrous state to form a sheet, and then chemically modified. However, in the case of wood, the chemical modification rate is as low as 7.2 mol% as in Example 6 of the patent document, and according to the study by the present inventors, coloring is performed when heated in the post-treatment of the composite. There was a problem of doing. Further, in the case of bacterial cellulose (Natadecoko), a chemical modification rate of about 5.6 mol% was obtained as in Example 1 of the patent document, but according to the study by the present inventors, There was a problem that the porosity of the nonwoven fabric was low, and the matrix was difficult to impregnate the nonwoven fabric when it was made into a composite material, resulting in a decrease in transparency of the composite material.

In Patent Document 2, a non-woven fabric having a porosity of 35 to 95% by volume is obtained by a production method in which a fine cellulose dispersion is made by paper and then dried after substitution with an organic solvent. However, this patent document does not specifically describe chemical modification. According to the study by the present inventors, if the chemical modification rate of cellulose is too low, there is a problem that it is colored when heated in the post-combination process. Conversely, if the chemical modification rate is too high, There was a problem that the linear expansion coefficient of the composite material was increased.
JP 2007-51266 A JP 2006-316253 A

  The present invention has been made in view of the above-described conventional situation, and by obtaining a cellulose nonwoven fabric with controlled porosity and chemical modification rate, when it is made into a composite material, it is highly transparent and non-coloring An object is to realize a low linear expansion coefficient.

  The cellulose nonwoven fabric of the present invention (Claim 1) is a chemically modified cellulose nonwoven fabric, characterized in that the chemical modification rate is 8 to 65 mol% with respect to the total hydroxyl groups of cellulose, and the porosity is 35% by volume or more. And

  The cellulose nonwoven fabric according to claim 2 is characterized in that, in claim 1, the chemical modification rate is 8 to 50 mol%.

  The cellulose nonwoven fabric according to claim 3 is characterized in that, in claim 1 or 2, the porosity is 60% by volume or less.

  The manufacturing method of the cellulose nonwoven fabric of this invention (Claim 4) is a method of manufacturing the cellulose nonwoven fabric as described in any one of Claims 1 thru | or 3, Comprising: After making cellulose into a nonwoven fabric, it chemically modifies. Features.

  The manufacturing method of the cellulose nonwoven fabric of this invention (Claim 5) is a method of manufacturing the cellulose nonwoven fabric as described in any one of Claim 1 thru | or 3, Comprising: It is set as a nonwoven fabric after chemically modifying a cellulose. Features.

  The method for producing a cellulose nonwoven fabric according to claim 6 is characterized in that in claim 4 or 5, the cellulose is washed with an organic solvent and then made into a nonwoven fabric.

  A composite material according to the present invention (invention 7) is characterized by including the cellulose nonwoven fabric according to any one of claims 1 to 3 and a resin other than cellulose.

  According to the present invention, by controlling the porosity of the cellulose nonwoven fabric, the resin can be easily impregnated, and a highly transparent composite material can be obtained. Expansion coefficient can be expressed. Furthermore, by controlling the chemical modification rate, the effect of reducing the water absorption rate of the resulting composite material and increasing the affinity between cellulose and the resin is exhibited.

  Embodiments of the present invention will be specifically described below, but the present invention is not limited to the following embodiments, and various modifications can be made within the scope of the gist of the present invention.

[Cellulose nonwoven fabric]
The cellulose nonwoven fabric of the present invention is a chemically modified cellulose nonwoven fabric characterized in that the chemical modification rate is 8 to 65 mol% with respect to the total hydroxyl groups of cellulose and the porosity is 35% by volume or more.

  The cellulose nonwoven fabric according to the present invention is a nonwoven fabric mainly composed of cellulose, and is an aggregate of cellulose fibers. The cellulose nonwoven fabric can be obtained by a method of forming a cellulose dispersion by papermaking or coating, or a method of drying a gel film.

<Film thickness>
The thickness of the cellulose nonwoven fabric of the present invention is not particularly limited, but is preferably 1 μm or more, more preferably 5 μm or more, particularly preferably 10 μm or more, 1 mm or less, more preferably 500 μm or less, particularly preferably 250 μm or less. is there. The thickness of the cellulose nonwoven fabric is preferably not less than the above lower limit from the viewpoint of production stability and strength, and is preferably not more than the above upper limit from the viewpoint of productivity, uniformity, and resin impregnation.

<Fiber diameter>
It is preferable that the fiber diameter of the cellulose fiber which comprises the cellulose nonwoven fabric of this invention is thin. Specifically, it is preferable not to include fibers having a fiber diameter of 1500 nm or more, more preferably not including fibers having a fiber diameter of 1000 nm or more, particularly preferably including fibers having a fiber diameter of 500 nm or more. Preferably it is not. Nonwoven fabrics that do not contain fibers having a fiber diameter of 1500 nm or more are preferable in that when they are combined with a resin, a nonwoven fabric having high transparency and a low coefficient of linear expansion is obtained.
In addition, the fiber diameter of a cellulose fiber can be confirmed by SEM observation.

  It is preferable that the fiber diameter of the cellulose fiber in the cellulose nonwoven fabric of this invention observed from SEM is 4 to 400 nm on average. If the average fiber diameter of the cellulose fibers exceeds 400 nm, the transparency is lowered, which is not preferable. Further, fibers having a fiber diameter of less than 4 nm cannot be substantially produced. From the viewpoint of transparency, the average fiber diameter of the cellulose fibers is preferably 4 to 200 nm, more preferably 4 to 100 nm.

<Color>
The color of the cellulose nonwoven fabric of the present invention is preferably white. The cellulose nonwoven fabric of the present invention is composed of cellulose fibers having a small fiber diameter as described above. However, since there is a void, the cellulose nonwoven fabric itself is not substantially transparent, and is impregnated with a resin to form a composite. It becomes transparent later. In that case, it is preferable that it is colorless. Therefore, it is preferable that the nonwoven fabric itself is white.

  Due to the nature of cellulose, the non-woven fabric is hardly bluish or reddish, and may be yellowish due to the raw material or may be yellowish by subsequent chemical modification. In particular, when using a raw material derived from wood, a yellowish color may be obtained depending on the degree of purification. When the non-woven fabric has a yellowish color, it is not preferable because it shows a yellowish color even when it is transparent.

  Such yellowness can be evaluated by measuring the yellow index (hereinafter YI). A larger YI value indicates stronger yellowness. The YI value of the cellulose nonwoven fabric in the present invention is preferably 40 or less, more preferably 35 or less, and further preferably 30 or less. The YI value can be measured using, for example, a color computer manufactured by Suga Test Instruments.

<Moisture content>
Since cellulose is inherently hydrophilic, moisture content may be a problem when used as a material. When the moisture content of the cellulose nonwoven fabric of the present invention is high, polymerization may be inhibited or the performance of the resin may be lowered when complexed. In addition, when the moisture content of the composite material is high, it is not preferable when used as a material because it causes corrosion, causes malfunction, or the composite material stretches due to water absorption and causes warping. The water content is the amount of water that the cellulose nonwoven fabric can hold by water absorption, and is synonymous with water absorption.

  In the present invention, the moisture content can be lowered by chemically modifying the cellulose fiber. It is preferable that the moisture content of the cellulose nonwoven fabric of this invention is 3% or less in the following measuring method.

(Measurement method of moisture content of cellulose nonwoven fabric)
The cellulose non-woven fabric was conditioned at a temperature of 23 ° C. and a humidity of 50% for 48 hours or more, and this was increased from room temperature to 600 ° C. at 10 ° C./min in the air using a TG-DTA (differential thermothermal gravimetric measuring device). The weight loss rate (%) at 200 ° C. when heated is taken as the moisture content.

<Raw material>
Examples of the raw material of the cellulose nonwoven fabric include woody materials such as conifers and broad-leaved trees, bacterial cellulose produced by bacteria, cotton such as cotton linter and cotton lint, seaweeds such as valonia and sturgeon, and scallops. These natural celluloses are preferable because of their high crystallinity and low linear expansion. Bacterial cellulose is preferred in that it can be easily obtained with a fine fiber diameter. Cotton is also preferable in that it is easy to obtain a fine fiber diameter, and more preferable in terms of easy acquisition of raw materials. In addition, wood of conifers and hardwoods with fine fiber diameters can be obtained, and it is the largest amount of biological resources on the earth, and it is a sustainable resource that produces about 70 billion tons per year. Therefore, it contributes greatly to the reduction of carbon dioxide that affects global warming, which is advantageous from an economic point of view.

<Porosity>
The cellulose nonwoven fabric of the present invention has a porosity of 35% by volume or more. The porosity of the cellulose nonwoven fabric of the present invention is preferably 35% by volume or more and 60% by volume or less. If the porosity of the cellulose non-woven fabric is small, the chemical modification described later is difficult to proceed or the resin is difficult to impregnate, which is not preferable. Moreover, when it is set as a composite material when a porosity is high, since a linear expansion coefficient becomes large, it is unpreferable.

The porosity here refers to the volume ratio of the voids in the nonwoven fabric, and the porosity can be obtained from the area, thickness, and weight of the cellulose nonwoven fabric by the following formula.
Porosity (volume%) = {(1-B / (M × A × t)} × 100
Here, A is the area (cm ² ) of the nonwoven fabric, t (cm) is the thickness, B is the weight (g) of the nonwoven fabric, M is the density of cellulose, and M = 1.5 g / cm ³ is assumed in the present invention. To do. The film thickness of a cellulose nonwoven fabric measures 10 points | pieces about the various positions of a nonwoven fabric using a film thickness meter (Mitutoyo Co., Ltd. IP65), and employ | adopts the average value.

  When calculating | requiring the porosity of the cellulose nonwoven fabric in a composite material, a porosity can be calculated | required by image-analyzing the SEM observation of the cross section of a cellulose nonwoven fabric.

<Chemical modification>
The cellulose nonwoven fabric of the present invention is a chemically modified nonwoven fabric. The chemical modification means that the hydroxyl group in cellulose is chemically modified by reacting with a chemical modifier.

(type)
As functional groups to be introduced into cellulose by chemical modification, acetyl group, acryloyl group, methacryloyl group, propionyl group, propioroyl group, butyryl group, 2-butyryl group, pentanoyl group, hexanoyl group, heptanoyl group, octanoyl group, nonanoyl group, Decanoyl group, undecanoyl group, dodecanoyl group, myristoyl group, palmitoyl group, stearoyl group, pivaloyl group, benzoyl group, naphthoyl group, nicotinoyl group, isonicotinoyl group, furoyl group, acyl group such as cinnamoyl group, 2-methacryloyloxyethylisocyanoyl Isocyanate group such as a group, methyl group, ethyl group, propyl group, 2-propyl group, butyl group, 2-butyl group, tert-butyl group, pentyl group, hexyl group, heptyl group, octyl group, noni Group, decyl group, undecyl group, dodecyl group, myristyl group, palmityl group, an alkyl group such as a stearyl group, an oxirane group, an oxetane group, a thiirane group, or the like thietane group. Among these, an acyl group having 2 to 12 carbon atoms such as an acetyl group, an acryloyl group, a methacryloyl group, a benzoyl group and a naphthoyl group, and an alkyl group having 1 to 12 carbon atoms such as a methyl group, an ethyl group and a propyl group are preferable. .

(Modification method)
The modification method is not particularly limited, and there is a method of reacting cellulose with a chemical modifier as described below. Although there are no particular limitations on the reaction conditions, a solvent, a catalyst, or the like may be used, or heating, decompression, or the like may be performed as necessary.

  As a kind of chemical modifier, 1 type, or 2 or more types chosen from the group which consists of cyclic ethers, such as an acid, an acid anhydride, alcohol, a halogenating reagent, isocyanate, alkoxysilane, and an oxirane (epoxy), are mentioned.

  Examples of the acid include acetic acid, acrylic acid, methacrylic acid, propanoic acid, butanoic acid, 2-butanoic acid, and pentanoic acid.

Examples of the acid anhydride include acetic anhydride, acrylic anhydride, methacrylic anhydride, propanoic anhydride, butanoic anhydride, 2-butanoic anhydride, and pentanoic anhydride.
Examples of the halogenating reagent include acetyl halide, acryloyl halide, methacryloyl halide, propanoyl halide, butanoyl halide, 2-butanoyl halide, pentanoyl halide, benzoyl halide, and naphthoyl halide.
Examples of the alcohol include methanol, ethanol, propanol, and 2-propanol.
Examples of the isocyanate include methyl isocyanate, ethyl isocyanate, propyl isocyanate, and the like.
Examples of the alkoxysilane include methoxysilane and ethoxysilane.
Examples of cyclic ethers such as oxirane (epoxy) include ethyl oxirane and ethyl oxetane.

Among these, acetic anhydride, acrylic acid anhydride, methacrylic acid anhydride, benzoyl halide, and naphthoyl halide are particularly preferable.
These chemical modifiers may be used alone or in combination of two or more.

(Chemical modification rate)
The term “chemical modification rate” as used herein refers to the proportion of all hydroxyl groups in cellulose that have been chemically modified, and the chemical modification rate can be measured by the following titration method.

これを解いていくと、以下の通りである。

<Measuring method>
0.05 g of cellulose nonwoven fabric is precisely weighed, and 6 ml of methanol and 2 ml of distilled water are added thereto. This is stirred at 60-70 ° C. for 30 minutes, and then 10 ml of 0.05N aqueous sodium hydroxide solution is added. The mixture is stirred at 60 to 70 ° C. for 15 minutes and further stirred at room temperature for one day. Titrate with 0.02N aqueous hydrochloric acid using phenolphthalein.
Here, from the amount Z (ml) of the 0.02N hydrochloric acid aqueous solution required for the titration, the number of moles Q of the substituent introduced by chemical modification is obtained by the following formula.
Q (mol) = 0.05 (N) × 10 (ml) / 1000
−0.02 (N) × Z (ml) / 1000
The relationship between the number of moles Q of the substituent and the chemical modification rate X (mol%) is calculated by the following formula (cellulose = (C ₆ O ₅ H ₁₀ ) _n = (162.14) _n , repetition Number of hydroxyl groups per unit = 3, molecular weight of OH = 17). In the following, T is the molecular weight of the substituent.

Solving this, it is as follows.

  The chemical modification rate of the cellulose nonwoven fabric of the present invention is usually 8 mol% or more, preferably 15 mol% or more, and usually 65 mol% or less, preferably 50 mol% or less, more preferably 40 mol% or less, based on the total hydroxyl groups of cellulose. Preferably it is 35 mol% or less.

By chemically modifying cellulose, the decomposition temperature of cellulose increases and heat resistance increases.
If this chemical modification rate is too low, the effect of improving heat resistance will be insufficient, and it may be colored when heated in the post-treatment of the composite. If the chemical modification rate is too high, the cellulose structure will be destroyed. Since the crystallinity is lowered, there is a problem that the linear expansion coefficient of the obtained composite material is increased, which is not preferable. On the other hand, when the chemical modification rate is too low, the hydrophilicity of the non-woven fabric increases and the water content increases, which is not preferable. In particular, when wood is used as the cellulose raw material, if the chemical modification rate is low, it will be colored when heated in post-combination, and the nonwoven fabric will be colored after the chemical modification reaction even if the chemical modification rate is high. It is not preferable because it is not easy.

[Method for producing cellulose nonwoven fabric]
If the cellulose nonwoven fabric of this invention satisfy | fills the above-mentioned chemical modification rate and porosity, the manufacturing method will not be specifically limited. The chemical modification may be performed on the cellulose before forming the nonwoven fabric, or may be performed after the cellulose is made into the nonwoven fabric. However, when forming the cellulose on the nonwoven fabric, the cellulose is washed with an organic solvent and then the nonwoven fabric. It is preferable that

  In the production of the nonwoven fabric, the cellulose raw material is refined or refined as necessary, and then the cellulose dispersion (usually an aqueous dispersion of cellulose) is formed by filtration or coating to form a gel film. The film is dried to form a non-woven fabric, but it is preferably washed or immersed in an organic solvent such as alcohol before the drying.

  As described above, the chemical modification may be performed after forming a film on a non-woven fabric, or may be performed on cellulose before forming the film on the non-woven fabric. From the viewpoint of production efficiency, it is preferable to chemically modify cellulose before forming it into a nonwoven fabric. In addition, it is preferable to perform chemical modification after forming a film on a non-woven fabric in terms of easily achieving both high chemical modification rate and transparency. In either case, when forming a film of cellulose, water is replaced with an organic solvent such as alcohol. When chemical modification is performed after forming a film on a nonwoven fabric, it is preferable to wash well with water after the chemical modification is completed, and then replace the remaining water with an organic solvent such as alcohol and dry.

  The method for producing such a nonwoven fabric will be described in more detail.

<Manufacture of non-woven fabric>
For the production of the nonwoven fabric, refined cellulose fibers are used.
When bacterial cellulose is used as a cellulose raw material, cellulose fibers can be obtained by culturing bacteria that produce cellulose. By removing this product from the medium and removing it by washing it with water or treating it with alkali, for example, water-containing bacterial cellulose containing no bacteria can be obtained. Since bacteria produce fine cellulose, they can be used as they are without being refined.
After refining wood such as conifers and hardwoods, and cotton such as cotton linters and cotton lint, they are refined to obtain refined cellulose. Further, seaweeds such as valonia and squirrel and squirts of sea squirts are refined to obtain refined cellulose.

As a disperser for refining cellulose, it is preferable to use a blender type high-speed rotary disperser, a stone mill type grinder such as a grinder, a high-pressure homogenizer, an ultrahigh-pressure homogenizer, an ultrasonic homogenizer, or the like.
When using a blender type high-speed rotating disperser, the rotational speed is preferably as high as possible, for example, 10,000 rpm or more, preferably 15,000 rpm or more, and 1 minute or more, preferably 10 minutes or more. Is preferred. When using a stone mill type disperser such as a grinder, it is preferable that the gap is somewhat small. Further, the number of rotations is preferably higher to some extent, for example, 1000 rpm or more. The number of passes through the stone mortar is, for example, one or more times, preferably two or more times.
When using a high-pressure homogenizer, it is preferable to operate at a high pressure as much as possible, for example, 15 MPa or more. Moreover, the frequency | count which passes a high voltage | pressure part is 1 time or more, for example, Preferably it is 2 times or more.
Also when using an ultra-high pressure homogenizer, it is preferable to operate at a high pressure as much as possible, for example, 100 MPa or more, preferably 150 MPa or more. Moreover, the frequency | count which passes a high voltage | pressure part is 1 time or more, for example, Preferably it is 2 times or more.
When an ultrasonic homogenizer is used, the frequency is preferably 15 kHz or more and the effective output density is preferably 1 W / cm ² or more. The treatment time is 5 minutes or longer, preferably 10 minutes or longer. Further, when an ultrasonic homogenizer is used, it is preferably centrifuged after that.
In particular, it is effective to uniformly refine cellulose by carrying out treatment using an ultrasonic homogenizer after it is refined with a blender type disperser, a high-pressure homogenizer, or an ultra-high pressure homogenizer.

  It is preferable that the cellulose concentration of the cellulose dispersion at the time of refining is 0.05% by weight or more, preferably 0.1% by weight or more, and more preferably 0.3% by weight or more. If the cellulose concentration is too low, it takes too much time to filter and apply. The cellulose concentration is 10% by weight or less, preferably 3% by weight or less, and more preferably 2.0% by weight or less. If the cellulose concentration is too high, the viscosity becomes too high or uniform fine cellulose cannot be obtained.

  When a nonwoven fabric is obtained by filtration, the concentration of the cellulose dispersion is preferably 0.01% by weight or more, preferably 0.05% by weight or more, and more preferably 0.1% by weight or more. If the concentration is too low, filtration takes an enormous amount of time, which is not preferable. The concentration of the cellulose dispersion is 1.5% by weight or less, preferably 1.2% by weight or less, more preferably 1.0% by weight or less. If the concentration is too high, a uniform nonwoven fabric cannot be obtained.

In addition, as a filter cloth at the time of filtration, it is important that fine cellulose does not pass through and the filtration rate is not too slow. Such a filter cloth is preferably a nonwoven fabric, a woven fabric, or a porous membrane made of an organic polymer. As the organic polymer, non-cellulosic organic polymers such as polyethylene terephthalate, polyethylene, polypropylene, polytetrafluoroethylene (PTFE), and nylon are preferable. These may be used alone or as a mixture.
Specific examples include a porous film of polytetrafluoroethylene having a pore diameter of 0.1 to 5 μm, for example, 1 μm, and a polyethylene terephthalate, polyethylene or nylon fabric having a pore diameter of 0.1 to 5 μm, for example, 1 μm.

  The cellulose nonwoven fabric of the present invention preferably has a certain range of porosity. However, as a method for obtaining such a nonwoven fabric with such a porosity, water in cellulose is finally used as an organic solvent such as alcohol in the film-forming process by filtration. The method of substitution can be mentioned. In this method, water is removed by filtration, and an organic solvent such as alcohol is added when the cellulose content reaches 5 to 99% by weight. Alternatively, the organic dispersion such as alcohol can be replaced with the organic solvent such as alcohol at the end of the filtration by introducing the cellulose dispersion into the filtration apparatus and then gently introducing an organic solvent such as alcohol onto the dispersion.

  The organic solvent such as alcohol used here is not particularly limited. For example, in addition to alcohols such as methanol, ethanol, 1-propanol, 2-propanol, and 1-butanol, acetone, methyl ethyl ketone, tetrahydrofuran, cyclohexane 1 type, or 2 or more types of organic solvents, such as toluene and carbon tetrachloride. When using a water-insoluble organic solvent, it is preferable to use a water-soluble organic solvent or a mixed solvent with the water-soluble organic solvent, and then replace with a water-insoluble organic solvent.

<Chemical modification of cellulose>
As described above, chemical modification may be performed on cellulose before film formation on a nonwoven fabric, or chemical modification may be performed after film formation on a nonwoven fabric.

  When chemically modifying the cellulose before forming into a non-woven fabric, the raw crude cellulose may be chemically modified, may be chemically modified to refined cellulose, and then chemically refined to fine cellulose after refinement. Although it may be modified, it is preferable to chemically modify the cellulose after purification from the viewpoint that the chemical modifier can react efficiently.

  In this case, the chemical modification can be performed by a normal method. However, since the purified cellulose is usually in a water-containing state, the water is replaced with a reaction solvent or the like, and the reaction between the chemical modifier and water is performed as much as possible. It is important to suppress. Moreover, since it will become difficult to advance refinement | miniaturization later when drying in order to remove water here, it is not preferable to put a drying process.

  The chemical modification can take a usual method. That is, chemical modification can be performed by reacting cellulose with a chemical modifier according to a conventional method. At this time, if necessary, a solvent or a catalyst may be used, or heating, decompression, or the like may be performed. As the catalyst, it is preferable to use a basic catalyst such as pyridine, triethylamine, sodium hydroxide or sodium acetate, or an acidic catalyst such as acetic acid, sulfuric acid or perchloric acid.

  As the temperature condition, if it is too high, yellowing of the cellulose, a decrease in the degree of polymerization, or the like may occur, and if it is too low, the reaction rate decreases, so 10 to 130 ° C. is preferable. The reaction time is several minutes to several tens of hours depending on the chemical modifier and the chemical modification rate.

After performing chemical modification in this way, it is preferable to wash thoroughly with water in order to terminate the reaction. If the unreacted chemical modifier remains, it is not preferable because it causes coloring later or becomes a problem when it is combined with the resin.
Thereafter, if the chemically modified cellulose is crude cellulose before purification, purification is performed after the chemical modification, and further refined and formed into a nonwoven fabric. In the case where the cellulose after the chemical modification is chemically modified, it is refined after the chemical modification and formed into a nonwoven fabric. Moreover, when chemically modifying fine cellulose, a film is formed after the chemical modification to obtain a nonwoven fabric. When the non-woven fabric is used, for example, when the non-woven fabric is obtained by filtering the fine cellulose dispersion, water in the cellulose is finally replaced with an organic solvent such as alcohol in the film-forming step by filtration.

In the case where the cellulose is chemically modified after the cellulose is formed on the nonwoven fabric, as described above, after the nonwoven fabric is manufactured, after being replaced with an organic solvent such as alcohol, the nonwoven fabric is further dried and then chemically modified. The chemical modification may be performed without drying, but it is preferable to perform the modification after drying because the reaction rate of the chemical modification is increased. In the case of drying, it may be blown dry, dried under reduced pressure, or dried under pressure. Moreover, you may heat.
The chemical modification of the nonwoven fabric can be performed by a usual method, and specifically, it is the same as the case of chemically modifying cellulose before forming the above-mentioned nonwoven fabric.

  Even when the non-woven fabric is chemically modified, it is preferable to thoroughly wash with water after the chemical modification in order to terminate the reaction. If the unreacted chemical modifier remains, it is not preferable because it causes coloring later or becomes a problem when it is combined with the resin. In addition, after sufficiently washing with water, the remaining water is preferably replaced with an organic solvent such as alcohol. In this case, the nonwoven fabric can be easily replaced by immersing it in an organic solvent such as alcohol.

<Dry>
Even if the chemical modification is performed before forming the film on the nonwoven fabric, or the chemical modification is performed after forming the film on the nonwoven fabric, the nonwoven fabric is finally dried. Alternatively, it may be dried under pressure. Moreover, you may heat-dry. When heating, the temperature is preferably 50 ° C or higher, more preferably 80 ° C or higher, 250 ° C or lower is more preferable, and 150 ° C or lower is more preferable. If the heating temperature is too low, drying may take time or drying may be insufficient, and if the heating temperature is too high, the nonwoven fabric may be colored or decomposed. Moreover, when pressurizing, 0.01 MPa or more is preferable, 0.1 MPa or more is more preferable, 5 MPa or less is preferable, and 1 MPa or less is more preferable. If the pressure is too low, drying may be insufficient, and if the pressure is too high, the cellulose nonwoven fabric may be crushed or decomposed.

[Composite material]
The composite material of the present invention is a composite of the above-described cellulose nonwoven fabric of the present invention and a resin other than cellulose.
In this case, as the resin other than cellulose, one or more resins such as a thermoplastic resin, a thermosetting resin, and a photocurable resin can be used. Resins other than cellulose that can be combined will be described later.
The voids in the nonwoven fabric portion in the composite material using the cellulose nonwoven fabric of the present invention are filled with the resin used in such a composite material. Basically, the gap when the nonwoven fabric is made is maintained and filled with resin.

<Composite ratio>
In the composite material of the present invention, the content ratio of the composite material and the resin other than cellulose is not particularly limited. Usually, the cellulose nonwoven fabric is 1% by weight or more and 99% by weight or less, and the resin other than cellulose is 1% by weight or more. 99% by weight or less. In order to develop low linear expansion, the cellulose nonwoven fabric needs to be 1% by weight or more and the resin other than cellulose needs to be 99% by weight or less, and in order to express transparency, the cellulose nonwoven fabric is 99% by weight or less, cellulose. It is necessary that the resin other than 1% by weight or more. The preferred range is 2% to 90% by weight of the cellulose nonwoven fabric, 10% to 98% by weight of the resin other than cellulose, and the more preferred range is 5% to 80% by weight of the cellulose nonwoven fabric. The resin other than cellulose is 20% by weight or more and 95% by weight or less.

  The resin content (or cellulose content) of the composite material can be determined from the weight of the cellulose nonwoven fabric before impregnation with the resin and the weight of the composite material after impregnation. Alternatively, the composite material may be immersed in a solvent in which the resin is soluble to remove only the resin, and the composite material may be obtained from the weight of the remaining cellulose nonwoven fabric. In addition, there are a method for obtaining from the specific gravity of the resin and a method for obtaining by quantitatively determining the functional groups of the resin and cellulose using NMR and IR.

<Thickness>
In the present invention, the thickness of the composite material is preferably 20 μm or more and 10 mm or less. Strength can be maintained by using a composite material having such a thickness. The thickness of the composite material is more preferably 25 μm or more, particularly preferably 30 μm or more, preferably 8 mm or less, particularly preferably 5 mm or less.
The composite material of the present invention is preferably in the form of a film (film) or plate having such a thickness, but is not limited to a flat film or flat plate, and may be a film or plate having a curved surface. . Other irregular shapes may also be used. Further, the thickness is not necessarily uniform, and may be partially different.

<Laminated body>
In the present invention, a laminate can be obtained by stacking a plurality of composite materials. A thick film can be formed by applying a heat press treatment to the laminate.
The thick film composite material can be used as a glazing or structural material.

<Manufacturing method>
As a method for producing the composite material of the present invention, the cellulose nonwoven fabric of the present invention is impregnated with a monomer of a resin other than cellulose and polymerized, and a thermosetting resin precursor or a photocurable resin precursor is impregnated and cured. And a method in which a resin solution other than cellulose resin is impregnated and dried, and then contacted with a heating press or the like, a method of impregnating a melt of a thermoplastic resin other than cellulose resin and contacted with a heating press or the like.

  Examples of a method for polymerizing a cellulose nonwoven fabric by impregnating the monomer include a method in which a cellulose nonwoven fabric is impregnated with a monomer of a thermoplastic resin and, if necessary, a polymerization catalyst or an initiator, and polymerized by heating or the like to obtain a composite material. .

  As a method of impregnating and curing a thermosetting resin precursor or a photocurable resin precursor, a mixture of a thermosetting resin precursor such as an epoxy resin or a photocurable resin precursor such as an acrylic resin and a curing agent Can be impregnated into a cellulose non-woven fabric, and a method of obtaining a composite material by curing the thermosetting resin precursor or the photocurable resin precursor with heat or light or the like.

When curing by radiation, the amount of radiation to be irradiated is arbitrary as long as the photopolymerization initiator generates radicals. However, if it is extremely small, the polymerization is incomplete, so the heat resistance of the cured product, the machine If the properties are not fully expressed, and extremely excessive, on the other hand, the cured product is deteriorated by light such as yellowing. Therefore, in accordance with the monomer composition and the type and amount of the photopolymerization initiator, Ultraviolet rays are preferably irradiated in the range of 0.1 to 200 J / cm ² . More preferably irradiated with a range of 1~20J / cm ^2. More preferably, the radiation is divided into a plurality of times. That is, when the first irradiation is performed for about 1/20 to 1/3 of the total irradiation amount and the necessary remaining amount is irradiated for the second and subsequent times, a cured product with smaller birefringence is obtained. Specific examples of the lamp used include an electrodeless mercury lamp, a metal halide lamp, a high pressure mercury lamp, an ultraviolet LED lamp, and the like.

  For the purpose of promptly completing the polymerization, photopolymerization and thermal polymerization may be performed simultaneously. In this case, curing is performed by heating the curable composition in the range of 30 to 300 ° C. simultaneously with the irradiation of radiation. In this case, a thermal polymerization initiator may be added to the curable composition in order to complete the polymerization, but if added in a large amount, the birefringence of the cured product is increased and the hue is deteriorated. The agent is used in an amount of 0.1 to 2 parts by weight, more preferably 0.3 to 1 part by weight, based on the total amount of monomers.

  As a method of impregnating a cellulose non-woven fabric with a resin solution other than cellulose resin and drying, and then adhering it with a heating press or the like, a resin other than cellulose is dissolved in a solvent in which the resin dissolves, and the cellulose non-woven fabric is impregnated with the solution and dried. The method of obtaining a composite material is mentioned. In this case, a higher performance composite material can be obtained by closely adhering the voids dried with a solvent after drying using a heating press or the like.

  As a method of impregnating a melt of a thermoplastic resin other than a cellulose resin and adhering it with a heating press or the like, a thermoplastic resin other than a cellulose resin is melted at a temperature equal to or higher than the glass temperature or the melting point thereof to form a cellulose nonwoven fabric. Examples of the method include impregnation and contact with a heating press or the like.

<Physical properties>
(transparency)
By obtaining a composite material composited with a transparent resin using the cellulose nonwoven fabric of the present invention, a material having high transparency, that is, low haze can be obtained. The haze value is preferably 20 or less, more preferably 10 or less, and particularly preferably 5 or less as the transparent material. The haze is measured using, for example, a haze meter manufactured by Suga Test Instruments, and the value of C light is used.

(Linear expansion coefficient)
By obtaining a composite material using the cellulose nonwoven fabric of the present invention, a material having a low linear expansion coefficient can be obtained. The linear expansion coefficient of the composite material of the present invention is preferably 0.5 to 50 ppm / K, more preferably 30 ppm / K or less, and particularly preferably 25 ppm / K or less. The linear expansion coefficient of the composite material is measured by the method shown in the section of Examples described later.

(Coloring)
By obtaining a composite material using the cellulose nonwoven fabric of the present invention, a composite material with small coloration can be obtained.
When yellowishness is derived from the raw material by using cellulose, yellowishness may be obtained by subsequent chemical modification. In particular, when a raw material derived from wood is used, a yellowish color may be obtained depending on the degree of purification. When the non-woven fabric has a yellowish color, it is not preferable because it shows a yellowish color even when it is transparent. Moreover, yellowishness may be derived from the resin to be combined.
The YI value of the composite material of the present invention is preferably 20 or less, more preferably 15 or less, and even more preferably 10 or less. The YI value can be measured using, for example, a color computer manufactured by Suga Test Instruments.

(Bending strength)
The composite material using the cellulose nonwoven fabric of the present invention has a flexural strength of preferably 40 MPa or more, more preferably 100 MPa or more. When the bending strength is lower than 40 MPa, sufficient strength cannot be obtained, which may affect the use of a structural material or the like to which a force is applied.

(Flexural modulus)
The composite material using the cellulose nonwoven fabric of the present invention has a flexural modulus of preferably 0.2 to 100 GPa, more preferably 1 to 50 GPa. If the flexural modulus is lower than 0.2 GPa, sufficient strength cannot be obtained, which may affect the use in applications where force is applied such as structural materials.

<Application>
The cellulose nonwoven fabric of the present invention has a low linear expansion coefficient because of the extended chain crystal of cellulose, and exhibits high elasticity and high strength. Further, when the cellulose fiber is made finer, when it is combined with a transparent resin, a composite material having high transparency and low coloring and haze can be obtained. Thus, since it is excellent in an optical characteristic, it is suitable as displays, substrates, and panels for liquid crystal displays, plasma displays, organic EL displays, field emission displays, rear projection televisions, and the like. In these applications, glass can be substituted as a flexible material, and effects such as weight reduction, flexibility, formability, and designability can be obtained.
Further, it can be used as a structural material other than the transparent material by utilizing characteristics such as a low linear expansion coefficient, high elasticity, and high strength. In particular, it is suitably used as automotive materials such as glazing, interior materials, outer plates and bumpers, personal computer casings, home appliance parts, packaging materials, building materials, civil engineering materials, marine products, and other industrial materials.

[Resin other than cellulose]
Hereinafter, in the composite material of the present invention, a resin other than cellulose that is combined with the cellulose nonwoven fabric, that is, a thermoplastic resin, a thermosetting resin, and a photocurable resin will be described.

  As thermoplastic resins, styrene resins, acrylic resins, aromatic polycarbonate resins, aliphatic polycarbonate resins, aromatic polyester resins, aliphatic polyester resins, aliphatic polyolefin resins, cyclic olefin resins, polyamides Resin, polyphenylene ether resin, thermoplastic polyimide resin, polyacetal resin, polysulfone resin, amorphous fluorine resin and the like.

  Examples of the styrenic resin include polymers and copolymers such as styrene, chlorostyrene, divinylbenzene, and α-methylstyrene.

  Examples of the acrylic resin include polymers and copolymers such as (meth) acrylic acid, (meth) acrylonitrile, (meth) acrylic acid ester, and (meth) acrylamide. Here, “(meth) acryl” means “acryl and / or methacryl”. Examples of (meth) acrylic acid esters include (meth) acrylic acid alkyl esters, (meth) acrylic acid monomers having a cycloalkyl ester group, and (meth) acrylic acid alkoxyalkyl esters. Examples of the (meth) acrylic acid alkyl ester include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, ( Examples include benzyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, hydroxyethyl (meth) acrylate, and the like. Examples of the (meth) acrylic acid monomer having a cycloalkyl group include cyclohexyl (meth) acrylate and isobornyl (meth) acrylate. Examples of (meth) acrylic acid alkoxyalkyl esters include 2-methoxyethyl (meth) acrylate, ethoxyethyl (meth) acrylate, and 2-butoxyethyl (meth) acrylate. (Meth) acrylamides include (meth) acrylamide, N-methyl (meth) acrylamide, N-ethyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, N -N-substituted (meth) acrylamides such as isopropyl (meth) acrylamide, Nt-octyl (meth) acrylamide and the like.

  Aromatic polycarbonate resin is produced by reaction of one or more bisphenols that can contain polyhydric phenols having 3 or more valences as a copolymerization component with carbonate esters such as bisalkyl carbonate, bisaryl carbonate, and phosgene. In order to make aromatic polyester carbonates as required, aromatic dicarboxylic acids such as terephthalic acid and isophthalic acid or derivatives thereof (for example, aromatic dicarboxylic acid diesters and aromatic dicarboxylic acids) Acid chloride) may be used.

  Examples of the bisphenols include bisphenol A, bisphenol C, bisphenol E, bisphenol F, bisphenol M, bisphenol P, bisphenol S, and bisphenol Z (for abbreviations, refer to the Aldrich reagent catalog). (Where the central carbon participates in the cyclohexane ring) is preferred, and bisphenol A is particularly preferred. Examples of copolymerizable trihydric phenols include 1,1,1- (4-hydroxyphenyl) ethane and phloroglucinol.

  The aliphatic polycarbonate resin is a copolymer produced by a reaction between an aliphatic diol component and / or an alicyclic diol component and a carbonic ester such as bisalkyl carbonate or phosgene. Examples of the alicyclic diol include cyclohexanedimethanol and isosorbite.

  Examples of aromatic polyester resins include copolymers of diols such as ethylene glycol, propylene glycol, and 1,4-butanediol and aromatic carboxylic acids such as terephthalic acid. Moreover, the copolymer of diols, such as bisphenol A, and aromatic carboxylic acids, such as a terephthalic acid and isophthalic acid, is also mentioned like a polyarylate.

  Examples of the aliphatic polyester resin include a copolymer of the diol and an aliphatic dicarboxylic acid such as succinic acid and valeric acid, and a copolymer of hydroxydicarboxylic acid such as glycolic acid and lactic acid.

  Specific examples of the aliphatic polyolefin resin include homopolymers of α-olefins having about 2 to 8 carbon atoms such as ethylene, propylene and 1-butene, those α-olefins, ethylene, propylene, 1-butene, 3-methyl-1-butene, 1-pentene, 4-methyl-1-pentene, 4,4-dimethyl-1-pentene, 1-hexene, 4-methyl-1-hexene, 1-heptene, Binary or ternary copolymers with other α-olefins having about 2 to 18 carbon atoms such as 1-octene, 1-decene, 1-octadecene, etc .; specifically, for example, branched low density Ethylene homopolymers such as polyethylene and linear high-density polyethylene, ethylene-propylene copolymers, ethylene-1-butene copolymers, ethylene-propylene-1-butene copolymers, ethylene Ethylene resins such as -4-methyl-1-pentene copolymer, ethylene-1-hexene copolymer, ethylene-1-heptene copolymer, ethylene-1-octene copolymer, propylene homopolymer, propylene -Propylene-based resins such as ethylene copolymer, propylene-ethylene-1-butene copolymer, 1-butene homopolymer, 1-butene-ethylene copolymer, 1-butene-propylene copolymer, etc. Butene-based resins, 4-methyl-1-pentene homopolymers, 4-methyl-1-pentene-based resins such as 4-methyl-1-pentene-ethylene copolymers, and ethylene and other α -Copolymers with olefins, copolymers of 1-butene with other α-olefins, such as 1,4-hexadiene, 4-methyl-1,4-hexadiene, 5-methyl 1,4-hexadiene, 6-methyl-1,5-heptadiene, 1,4-octadiene, 7-methyl-1,6-octadiene, cyclohexadiene, cyclooctadiene, dicyclopentadiene, 5-methylene-2-norbornene A binary or ternary copolymer with a nonconjugated diene such as 5-ethylidene-2-norbornene, 5-butylidene-2-norbornene, 5-isopropenyl-2-norbornene, and the like. -Olefin rubbers such as a propylene copolymer, an ethylene-propylene-nonconjugated diene copolymer, an ethylene-1-butene copolymer, and an ethylene-1-butene-nonconjugated diene copolymer. Two or more olefin polymers may be used in combination.

  The cyclic olefin-based resin is a polymer containing a cyclic olefin skeleton in a polymer chain, such as norbornene or cyclohexadiene, or a copolymer containing these. For example, a norbornene-based resin composed of a norbornene skeleton repeating unit or a copolymer of a norbornene skeleton and a methylene skeleton can be mentioned. "Apel" manufactured by Mitsui Chemicals, "Topas" manufactured by Chicona, and the like.

  Examples of polyamide resins include aliphatic amide resins such as 6,6-nylon, 6-nylon, 11-nylon, 12-nylon, 4,6-nylon, 6,10-nylon, 6,12-nylon, An aromatic polyamide such as an aromatic diamine such as phenylenediamine and an aromatic dicarboxylic acid such as terephthaloyl chloride or isophthaloyl chloride or a derivative thereof may be used.

  Examples of the polyphenylene ether resin include poly (2,6-dimethyl-1,4-phenylene ether), poly (2-methyl-6-ethyl-1,4-phenylene ether), and poly (2,6-dichloro ether). -1,4-phenylene ether), and a copolymer of 2,6-dimethylphenol and other phenols.

  Polyimide resins include pyromellitic acid-type imides such as polymellitic anhydride and 4,4′-diaminodiphenyl ether, aromatic diamines such as anhydrous trimellitic acid chloride and p-phenylenediamine, and diisocyanate compounds. From the copolymer of trimellitic acid type polyimide, biphenyltetracarboxylic acid, 4,4′-diaminodiphenyl ether, p-phenylenediamine, etc., benzophenone tetracarboxylic acid, 4,4′-diaminodiphenyl ether, etc. Benzophenone-type polyimide, bismaleimide, bismaleimide-type polyimide made of 4,4′-diaminodiphenylmethane, and the like.

  Examples of the polyacetal resin include a homopolymer having an oxymethylene structure as a unit structure and a copolymer containing an oxyethylene unit.

  Examples of the polysulfone resin include copolymers such as 4,4'-dichlorodiphenylsulfone and bisphenol A.

  Examples of the amorphous fluorine-based resin include homopolymers or copolymers such as tetrafluoroethylene, hexafluoropropylene, chlorotrifluoroethylene, vinylidene fluoride, vinyl fluoride, and perfluoroalkyl vinyl ether.

  These thermoplastic resins may be used individually by 1 type, and may use 2 or more types together.

  The thermosetting resin and the photocurable resin mean a relatively low molecular weight substance that is liquid, semi-solid, solid, or the like at room temperature and exhibits fluidity at room temperature or under heating. These can be insoluble and infusible resins formed by forming a network-like three-dimensional structure while increasing the molecular weight by causing a curing reaction or a crosslinking reaction by the action of a curing agent, a catalyst, heat or light. Here, the cured resin means a resin obtained by curing the thermosetting resin or the photocurable resin.

  The thermosetting resin is not particularly limited, but epoxy resin, acrylic resin, oxetane resin, phenol resin, urea resin, melamine resin, unsaturated polyester resin, silicon resin, polyurethane resin, diallyl phthalate resin, etc. Can be mentioned.

  The epoxy resin refers to an organic compound having at least one epoxy group. The number of epoxy groups in the epoxy resin is preferably 1 or more and 7 or less per molecule, and more preferably 2 or more per molecule. Here, the number of epoxy groups per molecule is obtained by dividing the total number of epoxy groups in the epoxy resin by the total number of molecules in the epoxy resin. It does not specifically limit as said epoxy resin, For example, the epoxy resin etc. which were shown below are mentioned. These epoxy resins may be used alone or in combination of two or more. These epoxy resins are thermosetting resin precursor epoxy compounds, and by using a curing agent, a cured epoxy resin that is a cured product of the epoxy resin can be obtained. For example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AD type epoxy resin, bisphenol type epoxy resin such as bisphenol S type epoxy resin, novolac type epoxy resin such as phenol novolac type epoxy resin, cresol novolac type epoxy resin, etc. And aromatic epoxy resins such as trisphenolmethane triglycidyl ether, hydrogenated products and brominated products thereof, and the like. 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, 3,4-epoxy-2-methylcyclohexyl-3,4-epoxy-2-methylcyclohexanecarboxylate, bis (3,4-epoxy Cyclohexyl) adipate, bis (3,4-epoxycyclohexyl) methyl adipate, bis (3,4-epoxy-6-methylcyclohexyl) methyl adipate, alicyclic epoxy resins such as bis (2,3-epoxycyclopentyl) ether, etc. Is mentioned. Also, 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin triglycidyl ether, trimethylolpropane triglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl Examples thereof include aliphatic epoxy resins such as polyglycidyl ethers of ethers and long-chain polyols containing polyoxyalkylene glycols containing 2 to 9 (preferably 2 to 4) carbon atoms, preferably polyoxyalkylene glycols and polytetramethylene ether glycols. . In addition, glycidyl ester type epoxy resins such as phthalic acid diglycidyl ester, tetrahydrophthalic acid diglycidyl ester, hexadrophthalic acid diglycidyl ester, diglycidyl-p-oxybenzoic acid, glycidyl ether-glycidyl ester of salicylic acid, dimer acid glycidyl ester, etc. And hydrogenated products thereof. Further, triglycidyl isocyanurate, N, N′-diglycidyl derivative of cyclic alkylene urea, glycidyl amine type epoxy resin of N, N, O-triglycidyl derivative of p-aminophenol, and hydrogenated products thereof can be mentioned. Moreover, the copolymer etc. of radical polymerizable monomers, such as glycidyl (meth) acrylate, ethylene, vinyl acetate, (meth) acrylic acid ester, etc. are mentioned. In addition, a polymer mainly composed of a conjugated diene compound such as epoxidized polybutadiene or a partially hydrogenated polymer obtained by epoxidizing an unsaturated carbon double bond may be used. Further, a polymer block mainly composed of a vinyl aromatic compound, such as epoxidized SBS, and a polymer block mainly composed of a conjugated diene compound or a polymer block of a partially hydrogenated product thereof are contained in the same molecule. Examples include epoxidized unsaturated carbon double bonds of a conjugated diene compound in a block copolymer. Moreover, the polyester resin etc. which have 1 or more per molecule, Preferably 2 or more epoxy group are mentioned. Examples thereof include urethane-modified epoxy resins and polycaprolactone-modified epoxy resins in which urethane bonds and polycaprolactone bonds are introduced into the structure of the epoxy resin. Examples of the modified epoxy resin include a rubber modified epoxy resin in which a rubber component such as NBR, CTBN, polybutadiene, and acrylic rubber is contained in the epoxy resin. In addition to the epoxy resin, a resin or oligomer having at least one oxirane ring may be added. Moreover, the thermosetting resin and composition containing a fluorene containing epoxy resin and a fluorene group, or its hardened | cured material is also mentioned. These fluorene-containing epoxy resins are suitably used because they contain a fluorene group in the molecule and thus have a high refractive index and high heat resistance. The curing agent used for the curing reaction of the epoxy resin is not particularly limited. For example, amine compounds, compounds such as polyaminoamide compounds synthesized from amine compounds, tertiary amine compounds, imidazole compounds, hydrazide compounds, melamine compounds. , Acid anhydrides, phenolic compounds, thermal latent cationic polymerization catalysts, photolatent cationic polymerization initiators, dicyanamide and derivatives thereof. These hardening | curing agents may be used independently and 2 or more types may be used together.

An oxetane resin is a compound having at least one oxetane ring. The number of oxetane rings in the oxetane resin monomer is preferably 1 or more and 4 or less per molecule. Examples of the compound having one oxetane ring in the molecule include 3-ethyl-3-hydroxymethyloxetane, 3-ethyl-3- (phenoxymethyl) oxetane, 3-ethyl-3- (2-ethylhexyloxymethyl) Oxetane, 3-ethyl {[3- (triethoxylyl) propoxy] methyl} oxetane, 3-ethyl-3-methacryloxymethyloxetane, and the like. Examples of the compound having two oxetane rings in the molecule include di [1-ethyl (3-oxetanyl)] methyl ether, 1,4-bis {[(3-ethyl-3-oxetanyl) methoxy] methyl} benzene, 4,4′-bis [(3-ethyl-3-oxetanyl) methoxymethyl] biphenyl and the like. Examples of the compound having 3 to 4 oxetane rings include a branched polyalkyleneoxy group and a reaction product of a polysiloxy group and 3-alkyl-3-methyloxetane.
The curing agent used for the curing reaction of the oxetane resin is not particularly limited. For example, amine compounds, compounds such as polyaminoamide compounds synthesized from amine compounds, tertiary amine compounds, imidazole compounds, hydrazide compounds, melamine compounds. , Acid anhydrides, phenolic compounds, thermal latent cationic polymerization catalysts, photolatent cationic polymerization initiators, dicyanamide and derivatives thereof. These hardening | curing agents may be used independently and 2 or more types may be used together. In particular, photocuring is preferably used from the viewpoint of effective use of energy. Here, photocuring is a compound that initiates cationic polymerization by irradiation with active energy rays, and examples thereof include diaryliodonium salts and triarylsulfonium salts.

  Examples of the phenol resin include those obtained by reacting phenols such as phenol and cresol with formaldehyde and the like to synthesize novolak and the like and then curing it with hexamethylenetetramine or the like.

  Examples of the urea resin include urea and a polymerization reaction product such as formaldehyde.

Examples of the melamine resin include polymerization reaction products such as melamine and formaldehyde.
Examples of the unsaturated polyester resin include a resin obtained by dissolving an unsaturated polyester obtained from an unsaturated polybasic acid or the like and a polyhydric alcohol or the like in a monomer to be polymerized therewith, and the like.

Examples of the silicon resin include those having an organopolysiloxane as a main skeleton.
Examples of the polyurethane resin include polymerization reaction products composed of diols such as glycol and diisocyanate.

  Examples of diallyl phthalate resins include reactants comprising diallyl phthalate monomers and diallyl phthalate prepolymers.

  There are no particular limitations on the curing agent and curing catalyst of these thermosetting resins. Examples of the curing agent include polyfunctional amines, polyamides, acid anhydrides, and phenol resins, and examples of the curing catalyst include imidazole. It is done. These can be used alone or as a mixture of two or more.

  Moreover, as a photocurable resin, the (meth) acrylate type polymer or copolymer formed by superposing | polymerizing or copolymerizing the compound which can be radically polymerized is mentioned.

Examples of the compound capable of radical polymerization include a monofunctional (meth) acrylate compound having one (meth) acryloyl group in the molecule, and a polyfunctional (meta) having 2 to 8 (meth) acryloyl groups in the molecule. ) Acrylate compound, epoxy (meth) acrylate, (meth) acrylate having urethane bond, alicyclic ring bis (meth) acrylate, alicyclic ring skeleton mono (meth) acrylate, styrene compound, acrylic acid derivative other than ester, etc. Is mentioned.
Furthermore, a chain transfer agent, an ultraviolet absorber, a filler, and a silane coupling agent can be added as necessary during the production of the photocurable resin.

Monofunctional (meth) acrylate compounds having one (meth) acryloyl group in the molecule include methyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, phenyl (meth) acrylate, benzyl (meth) acrylate, Examples include cyclohexyl (meth) acrylate.
Polyfunctional (meth) acrylate compounds having 2 to 8 (meth) acryloyl groups in the molecule include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetra Di (meth) acrylate of polyethylene glycol higher than ethylene glycol, 1,3-butylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 2-hydroxy- 1,3-di (meth) acryloxypropane, 2,2-bis [4- (meth) acryloyloxyphenyl] propane, bis (hydroxy) tricyclo [5.2.1.0 ^2,6 ] decane = diacrylate Bis (hydroxy) tricyclo [5 2.1.0 ^2,6] decane = dimethacrylate, bis (hydroxymethyl) tricyclo [5.2.1.0 ^2,6] decane = acrylate methacrylate, bis (hydroxy) pentacyclo [6.5.1.1 ^{3 , 6} . 0 ^2,7 . 0 ^9,13 ] pentadecane = diacrylate, bis (hydroxy) pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] pentadecane = dimethacrylate, bis (hydroxy) pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] pentadecane = acrylate methacrylate, 2,2-bis [4- (β- (meth) acryloyloxyethoxy) phenyl] propane, 2,2-bis [4- (β- (meth) acryloyloxyethoxy) Cyclohexyl] propane, 1,4-bis ((meth) acryloyloxymethyl) cyclohexane, trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (Meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol tri (meth) acrylate, tripentaerythritol octa (meth) acrylate , Tripentaerythritol septa (meth) acrylate, tripentaerythritol hexa (meth) acrylate, tripentaerythritol penta (meth) acrylate, tripentaerythritol tetra (meth) acrylate, tripentaerythritol tri (meth) acrylate.

Among these, bis (hydroxy) tricyclo [5.2.1.0 ^2,6 ] decane = diacrylate, bis (hydroxy) tricyclo [5.2.1.0 ^2,6 ] decane = dimethacrylate, bis ( Bis (hydroxy) tricyclo [5.2.1.0 ^2,6 ] decane = di (meth) acrylate such as hydroxy) tricyclo [5.2.1.0 ^2,6 ] decane = acrylate methacrylate, 2,2- Bis [4- (β-methacryloyloxyethoxy) phenyl] propane, 2,2-bis [4- (β-methacryloyloxyethoxy) cyclohexyl] propane, 1,4-bis (methacryloyloxymethyl) cyclohexane, trimethylolpropane tri Methacrylate is preferably used.

  Specific examples of the epoxy (meth) acrylate include, for example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenol novolac type epoxy resin, compound having an alicyclic epoxy group, and bisphenol A type propylene oxide addition type terminal glycidyl. A reaction product of ether, fluorene epoxy resin or the like and (meth) acrylic acid can be mentioned. Specifically, bisphenol A diglycidyl ether = di (meth) acrylate, bisphenol A dipropylene oxide diglycidyl ether = di (meth) acrylate, ethylene glycol diglycidyl ether = di (meth) acrylate, propylene glycol diglycidyl ether = di (Meth) acrylate, neopentyl glycol diglycidyl ether = di (meth) acrylate, 1,6-hexanediol diglycidyl ether = di (meth) acrylate, glycerin diglycidyl ether = di (meth) acrylate, trimethylolpropane triglycidyl Ether = tri (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, 3,4-epoxycyclohexylmethyl (meth) acrylate , 3,4-epoxycyclohexyl ethyl (meth) acrylate, 3,4-epoxycyclohexyl-butyl (meth) acrylate, 3,4-epoxycyclohexylmethyl-amino (meth) acrylate.

  Examples of the (meth) acrylate having a urethane bond in the molecule include urethane oligomers having 2 to 10 (preferably 2 to 5) (meth) acryloyl groups in one molecule. For example, there is a (meth) acryloyl group-containing urethane oligomer produced by reacting a urethane prepolymer obtained by reacting diisocyanates and diols with a hydroxy group-containing (meth) acrylate compound.

  Among the diols used here, as the polyols, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polyhexamethylene glycol, polyheptamethylene glycol, polydecamethylene glycol or two or more types of ion-polymerizable cyclic compounds are opened. Examples thereof include polyether diols obtained by copolymerization. Examples of the ion polymerizable cyclic compound include ethylene oxide, propylene oxide, butene-1-oxide, isobutene oxide, 3,3-bischloromethyloxetane, tetrahydrofuran, dioxane, trioxane, tetraoxane, cyclohexene oxide, styrene oxide, epichlorohydrin, glycidyl methacrylate, Examples include cyclic ethers such as allyl glycidyl ether, allyl glycidyl carbonate, butadiene monooxide, isoprene monooxide, vinyl oxetane, vinyl tetrahydrofuran, vinylcyclohexene oxide, phenyl glycidyl ether, butyl glycidyl ether, and benzoic acid glycidyl ester. Further, a polyether obtained by ring-opening copolymerization of the ionic polymerizable cyclic compound with a cyclic imine such as ethyleneimine, a cyclic lactone acid such as β-propiolactone or glycolic acid lactide, or dimethylcyclopolysiloxane. Diols can also be used. Specific combinations of the two or more ion-polymerizable cyclic compounds include tetrahydrofuran and propylene oxide, tetrahydrofuran and 2-methyltetrahydrofuran, tetrahydrofuran and 3-methyltetrahydrofuran, tetrahydrofuran and ethylene oxide, propylene oxide and ethylene oxide, butene oxide and ethylene oxide. Etc. The ring-opening copolymer of these ion-polymerizable cyclic compounds may be bonded at random or may be bonded in a block form.

  These polyether diols described so far include, for example, PTMG1000, PTMG2000 (manufactured by Mitsubishi Chemical Corporation), PPG1000, EXCENOL2020, 1020 (manufactured by Asahi Ohrin Co., Ltd.), PEG1000, Unisafe DC1100, DC1800 ( As described above, manufactured by NOF Corporation), PPTG2000, PPTG1000, PTG400, PTGL2000 (above, manufactured by Hodogaya Chemical Co., Ltd.), Z-3001-4, Z-3001-5, PBG2000A, PBG2000B (above, Daiichi Kogyo Seiyaku Co., Ltd.) It can also be obtained as a commercial product such as (made by Co., Ltd.).

  Examples of the polyol compound include polyester diol, polycarbonate diol, polycaprolactone diol and the like in addition to the above polyether diol. These diols can be used in combination with the polyether diol. The polymerization mode of these structural units is not particularly limited, and may be any of random polymerization, block polymerization, and graft polymerization. Examples of the polyester diol used here include ethylene glycol, polyethylene glycol, propylene glycol, polypropylene glycol, tetramethylene glycol, polytetramethylene glycol, 1,6-hexanediol, neopentyl glycol, 1,4-cyclohexanedimethanol, 3 -Polyhydric alcohols such as methyl-1,5-pentanediol, 1,9-nonanediol, 2-methyl-1,8-octanediol and phthalic acid, isophthalic acid, terephthalic acid, maleic acid, fumaric acid, adipic acid And polyester polyols obtained by reacting with a polybasic acid such as sebacic acid. As these commercially available products, Kurapol P-2010, PMIPA, PKA-A, PKA-A2, PNA-2000 (manufactured by Kuraray Co., Ltd.) and the like can be obtained.

  Examples of the polycarbonate diol include 1,6-hexane polycarbonate, and commercially available products include DN-980, 981, 982, 983 (manufactured by Nippon Polyurethane Co., Ltd.), PC-8000 (US PPG ( Etc.).

  Furthermore, as polycaprolactone diol, for example, ε-caprolactone and ethylene glycol, polyethylene glycol, propylene glycol, polypropylene glycol, tetramethylene glycol, polytetramethylene glycol, 1,2-polybutylene glycol, 1,6-hexanediol, neo Examples thereof include polycaprolactone diols obtained by reacting divalent diols such as pentyl glycol, 1,4-cyclohexanedimethanol and 1,4-butanediol. These diols are commercially available from Plaxel 205, 205AL, 212, 212AL, 220, 220AL (above, manufactured by Daicel Corporation).

  Many diols other than those described above can also be used. Examples of such diols include ethylene glycol, propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, 1,4-cyclohexanedimethanol, and bisphenol A. Ethylene oxide addition diol, bisphenol A butylene oxide addition diol, bisphenol F ethylene oxide addition diol, bisphenol F butylene oxide addition diol, hydrogenated bisphenol A ethylene oxide addition diol, hydrogenated bisphenol A butylene oxide addition diol, water Bisphenol F ethylene oxide addition diol, hydrogenated bisphenol F butylene oxide addition diol, dicyclopentadiene dimethylol compound , Tricyclodecane dimethanol, β-methyl-δ-valerolactone, hydroxy-terminated polybutadiene, hydroxy-terminated hydrogenated polybutadiene, castor oil-modified polyol, polydimethylsiloxane-terminated diol compound, polydimethylsiloxane carbitol-modified polyol, etc. .

  In addition to using the diol as described above, it is also possible to use a diamine together with a diol having a polyoxyalkylene structure. Examples of such a diamine include ethylenediamine, tetramethylenediamine, hexamethylenediamine, and paraphenylenediamine. Diamines such as 4,4'-diaminodiphenylmethane, diamines containing heteroatoms, polyether diamines, and the like.

  Preferable diol includes polytetramethylene ether glycol which is a polymer of 1,4-butanediol. The preferred molecular weight of this diol is usually 50 to 15,000 in terms of number average molecular weight, particularly 500 to 3,000.

  On the other hand, examples of diisocyanates include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, 1,5-naphthalene diisocyanate, and m-phenylene. Diisocyanate, p-phenylene diisocyanate, 3,3'-dimethyl-4,4'-diphenyl metadiisocyanate, 4,4'-diphenylmethane diisocyanate, 3,3'-dimethylphenylene diisocyanate, 4,4'-biphenylene diisocyanate, 1, 6-hexamethylene diisocyanate, methylene dicyclohexyl diisocyanate, methylene bis (4-cyclohexyl isocyanate), 2,2,4-trimethylhexamethylene diisocyanate, 1,4- Hexamethylene diisocyanate, bis (2-isocyanatoethyl) fumarate, 6-isopropyl-1,3-phenyl diisocyanate, isophorone diisocyanate, norbornane diisocyanate, lysine diisocyanate, and the like. These diisocyanates may be used alone or in combination of two or more. Of these, diisocyanates having an alicyclic skeleton such as isophorone diisocyanate, norbornane diisocyanate, and methylene dicyclohexyl diisocyanate are preferably used.

  Examples of the hydroxy group-containing (meth) acrylate compound used in the reaction include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, and 2-hydroxy-3- Phenyloxypropyl (meth) acrylate, 1,4-butanediol mono (meth) acrylate, 2-hydroxyalkyl (meth) acryloyl phosphate, 4-hydroxycyclohexyl (meth) acrylate, 1,6-hexanediol mono (meth) Acrylate, neopentyl glycol mono (meth) acrylate, trimethylolpropane di (meth) acrylate, trimethylolethane di (meth) acrylate, pentaerythritol tri (meth) acrylate, dipenta Risuri penta (meth) acrylate, further the alkyl glycidyl ether, allyl glycidyl ether, may also include compounds obtained by addition reaction of glycidyl (meth) glycidyl group-containing compounds such as acrylates and (meth) acrylic acid. Of these, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and the like are particularly preferable.

  Commercially available urethane oligomers include EB2ECRYL220 (Daicel Cytec), Art Resin UN-3320HA (Negami Kogyo), Art Resin UN-3320HB (Negami Kogyo), Art Resin UN-3320HC (Negami Kogyo), Art Resin UN-330 ( Negami Kogyo) and Art Resin UN-901T (Negami Kogyo), NK-oligo U-4HA (Shin Nakamura Chemical), NK-oligo U-6HA (Shin Nakamura Chemical), NK-oligo U-324A (Shin Nakamura Chemical), NK-oligo U-15HA (Shin Nakamura Chemical), NK-oligo U-108A (Shin Nakamura Chemical), NK-oligo U-200AX (Shin Nakamura Chemical), NK-oligo U-122P (Shin Nakamura Chemical), NK- Oligo U-5201 (Shin Nakamura Chemical), NK-Oligo U-340AX (Shin Nakamura Chemical), NK-Oligo U-511 (Shin Nakamura Chemical), NK-Oligo U-512 (Shin Nakamura Chemical), NK-Oligo U -311 (Shin Nakamura Chemical), NK-oligo UA-W1 (Shin Nakamura Chemical), NK-oligo UA-W2 (Shin Nakamura Chemical), NK-oligo UA-W3 (Shin Nakamura Chemical), NK-oligo UA-W4 (Shin Nakamura Chemical , NK-oligo UA-4000 (Shin-Nakamura Chemical), NK-oligo UA-100 (Shin-Nakamura Chemical), Purple light UV-1400B (Nippon Synthetic Chemical Industry), Purple light UV-1700B (Nippon Synthetic Chemical Industry), Purple light UV- 6300B (Nippon Synthetic Chemical Industry), purple light UV-7550B (Nippon Synthetic Chemical Industry), purple light UV-7600B (Nippon Synthetic Chemical Industry), purple light UV-7605B (Nippon Synthetic Chemical Industry), purple light UV-7610B (Nippon Synthetic Chemical Industry) ), Purple light UV-7620EA (Nippon Synthetic Chemical Industry), purple light UV-7630B (Nippon Synthetic Chemical Industry), purple light UV-7640B (Nippon Synthetic Chemical Industry), purple light UV-6630B (Nippon Synthetic Chemical Industry), purple light UV-7000B (Nippon Synthetic Chemical Industry), Purple Light UV-7510B (Nippon Synthetic Chemical Industry), Purple Light UV-7461TE (Nippon Synthetic Chemical Industry), Purple Light UV-3000B (Nippon Synthetic Chemical Industry), Purple Light UV-3200B (Nippon Synthetic Chemical Industry) , Purple light UV-3210EA (Nippon Synthetic Chemical Industry), purple light UV-3310B (Nippon Synthetic Chemical Industry), purple light UV-3500BA (Nippon Synthetic Chemical Industry), purple light UV-3520T L (Nippon Synthetic Chemical Industry), purple light UV-3700B (Nippon Synthetic Chemical Industry), purple light UV-6100B (Nippon Synthetic Chemical Industry), purple light UV-6640B (Nippon Synthetic Chemical Industry), etc. can be used.

  The number average molecular weight of the (meth) acrylate having a urethane bond in the molecule is preferably 1000 to 100,000, and more preferably 2,000 to 10,000. Among them, urethane acrylate having methylene dicyclohexyl diisocyanate and polytetramethylene ether glycol is excellent in terms of transparency, low birefringence, flexibility, and the like, and can be suitably used.

Specific examples of the alicyclic skeleton bis (meth) acrylate compound (hereinafter sometimes abbreviated as “bis (meth) acrylate”) include, for example, bis (acryloyloxy) tricyclo [5.2.1.0 ^2,6. ] Decane, bis (methacryloyloxy) tricyclo [5.2.1.0 ^2,6 ] decane, (acryloyloxy-methacryloyloxy) tricyclo [5.2.1.0 ^2,6 ] decane, bis (acryloyloxy) Pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] pentadecane, bis (methacryloyloxy) pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] pentadecane, (acryloyloxy-methacryloyloxy) pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] pentadecane, bis (acryloyloxymethyl) tricyclo [5.2.1.0 ^2,6 ] decane, bis (methacryloyloxymethyl) tricyclo [5.2.1.0 ^2,6 ] decane, ( Acryloyloxymethyl-methacryloyloxymethyl) tricyclo [5.2.1.0 ^2,6 ] decane, bis (acryloyloxymethyl) pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] pentadecane, bis (methacryloyloxymethyl) pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] pentadecane, (acryloyloxymethyl-methacryloyloxymethyl) pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] pentadecane, bis (acryloyloxyethyl) tricyclo [5.2.1.0 ^2,6 ] decane, bis (methacryloyloxyethyl) tricyclo [5.2.1.0 ^2,6 ] decane, ( Acryloyloxyethyl-methacryloyloxyethyl) tricyclo [5.2.1.0 ^2,6 ] decane, bis (acryloyloxyethyl) pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] pentadecane, bis (methacryloyloxyethyl) pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] pentadecane, (acryloyloxyethyl-methacryloyloxyethyl) pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] pentadecane, etc., and mixtures thereof.

Of these, bis (acryloyloxymethyl) tricyclo [5.2.1.0 ^2,6 ] decane, bis (methacryloyloxymethyl) tricyclo [5.2.1.0 ^2,6 ] decane and (acryloyloxymethyl) -Methacryloyloxymethyl) tricyclo [5.2.1.0 ^2,6 ] decane is preferred.

  Several of these bis (meth) acrylates can be used in combination.

Specific examples of the alicyclic skeleton mono (meth) acrylate compound (hereinafter sometimes abbreviated as “mono (meth) acrylate”) include, for example, (hydroxy-acryloyloxy) tricyclo [5.2.1.0 ^{2, 6} ] decane, (hydroxy-methacryloyloxy) tricyclo [5.2.1.0 ^2,6 ] decane, (hydroxy-acryloyloxy) pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] pentadecane, (hydroxy-methacryloyloxy) pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] pentadecane, (hydroxymethyl-acryloyloxymethyl) tricyclo [5.2.1.0 ^2,6 ] decane, (hydroxymethyl-methacryloyloxymethyl) tricyclo [5.2.1.0 ^2,6 Decane, (hydroxymethyl-acryloyloxymethyl) pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] pentadecane, (hydroxymethyl-methacryloyloxymethyl) pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] pentadecane, (hydroxyethyl-acryloyloxyethyl) tricyclo [5.2.1.0 ^2,6 ] decane, (hydroxyethyl-methacryloyloxyethyl) tricyclo [5.2.1.0 ^2,6 ] Decane, (hydroxyethyl-acryloyloxyethyl) pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] pentadecane, (hydroxyethyl-methacryloyloxyethyl) pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] pentadecane and the like. Moreover, these mixtures etc. can be mentioned.

Of these, bis (hydroxymethyl-acryloyloxymethyl) tricyclo [5.2.1.0 ^2,6 ] decane, bis (hydroxymethyl-methacryloyloxymethyl) tricyclo [5.2.1.0 ^2,6 ] Those selected from decane are preferred.

  Examples of the styrene compound include styrene, chlorostyrene, divinylbenzene, and α-methylstyrene.

  Examples of (meth) acrylic acid derivatives other than esters include acrylamide, methacrylamide, acrylonitrile, methacrylonitrile and the like.

  As the chain transfer agent, for example, a polyfunctional mercaptan compound having two or more thiol groups in the molecule can be used, and thereby moderate toughness can be imparted to the cured product. Examples of the mercaptan compound include pentaerythritol tetrakis (β-thiopropionate), pentaerythritol tetrakis (β-thioglycolate), trimethylolpropane tris (β-thiopropionate), trimethylolpropane tris (β-thiol). Glycolate), diethylene glycol bis (β-thiopropionate), diethylene glycol bis (β-thioglycolate), dipentaerythritol hexakis (β-thiopropionate), dipentaerythritol hexakis (β-thioglycolate) 2) to 6-valent thioglycolic acid ester or thiopropionic acid ester; tris [2- (β-thiopropionyloxy) ethyl] triisocyanurate, tris [2- (β-thioglyconyloxy) ethyl] triisocyanur Tris [2- (β-thiopropionyloxyethoxy) ethyl] triisocyanurate, tris [2- (β-thioglyconyloxyethoxy) ethyl] triisocyanurate, tris [2- (β-thiopropionyloxy) ) Propyl] triisocyanurate, tris [2- (β-thioglyconyloxy) propyl] triisocyanurate, and other ω-SH group-containing triisocyanurates; benzene dimercaptan, xylylene dimercaptan, 4, 4′-dimercapto Examples include α, ω-SH group-containing compounds such as diphenyl sulfide. Among these, one kind such as pentaerythritol tetrakis (β-thiopropionate), trimethylolpropane tris (β-thiopropionate), tris [2- (β-thiopropionyloxyethoxy) ethyl] triisocyanurate or the like Two or more are preferably used. When a mercaptan compound is added, it is usually contained in a proportion of 30% by weight or less with respect to the total of radically polymerizable compounds.

  The ultraviolet absorber is selected from benzophenone ultraviolet absorbers and benzotriazole ultraviolet absorbers, and one type of ultraviolet absorber may be used, or two or more types may be used in combination. Specifically, 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 2-hydroxy-4-octadecyloxybenzophenone, 2,2′-dihydroxy-4 Benzophenone compounds such as -methoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2- (2'-hydroxy-5-methylphenyl) benzotriazole, 2- (2'-hydroxy-3 ' , 5′-ditertiarybutylphenyl) benzotriazole, benzotriazole compounds such as 2- (2′-hydroxy-3′-tertiarybutyl-5′-methylphenyl) benzotriazole, and other malonate ester hostabin PR -25 (Clariant , Oxalic acid anilide-based San Dubois VSU (Clariant) is a compound such. When an ultraviolet absorber is added, it is usually contained at a ratio of 0.01 to 1 part by weight with respect to 100 parts by weight of the total of radically polymerizable compounds.

  Examples of the filler include inorganic particles and organic polymers. Examples thereof include inorganic particles such as silica particles, titania particles and alumina particles, transparent cycloolefin polymers such as Zeonex (Nippon Zeon) and Arton (JSR), and general-purpose thermoplastic polymers such as polycarbonate and PMMA. Among these, use of nano-sized silica particles is preferable because transparency can be maintained. In addition, it is preferable to use a polymer having a structure similar to that of the ultraviolet curable monomer because the polymer can be dissolved to a high concentration. For example, a polymer obtained by polymerizing an ultraviolet curable monomer (FA-513M) manufactured by Hitachi Chemical Co., Ltd. is suitable. As the polymerization method, well-known thermal polymerization can be used.

  Examples of the silane coupling agent include vinyltrichlorosilane, vinyltris (βmethoxyethoxy) silane, vinyltriethoxysilane, vinyltrimethoxysilane, γ-((meth) acryloxypropyl) trimethoxysilane, β- (3, 4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, N-β (aminoethyl) -γ-aminopropyltrimethoxysilane, N-β (Aminoethyl) -γ-aminopropylmethyldimethoxysilane, γ-aminopropyltrimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane, etc. Cited . Among them, γ-((meth) acryloxypropyl) trimethoxysilane, γ-((meth) acryloxypropyl) methyldimethoxysilane, γ-((meth) acryloxypropyl) methyldiethoxysilane, γ-((meta ) Acryloxypropyl) triethoxysilane, γ- (acryloxypropyl) trimethoxysilane and the like have a (meth) acryl group in the molecule, and are in common with other monomers in the curable composition according to the present invention. Since it can superpose | polymerize, it is preferable. The silane coupling agent is usually used in an amount of 0.1 to 50 parts by weight, preferably 1 to 20 parts by weight, particularly preferably 1 to 20 parts by weight, based on 100 parts by weight of the radical polymerizable compound. . When this proportion is less than 0.1 parts by weight, the effect of containing this is not sufficiently obtained, and when it is more than 50 parts by weight, optical properties such as transparency of the cured product are impaired. There is a fear.

The curable composition for combining the resin with the cellulose nonwoven fabric can be polymerized and cured by a known method to obtain a cured product.
For example, heat curing or radiation curing can be used. Radiation curing is preferable. Examples of the radiation include infrared rays, visible rays, ultraviolet rays, electron beams, and the like, preferably light. More preferred is light having a wavelength of about 200 nm to 450 nm, and even more preferred is ultraviolet light having a wavelength of 300 to 400 nm.

  Specifically, a method in which a thermal polymerization initiator that generates radicals upon heating is added to the curable composition in advance and polymerized by heating (hereinafter sometimes referred to as “thermal polymerization”), the curable composition in advance. A photopolymerization initiator that generates radicals by radiation such as ultraviolet rays is added to the polymer, and a method of polymerizing by irradiation with radiation (hereinafter sometimes referred to as “photopolymerization”), and a thermal polymerization initiator and photopolymerization start Examples include a method in which an agent is added in advance and polymerized by a combination of heat and light, and photopolymerization is more preferable in the present invention.

  As the photopolymerization initiator, a photoradical generator is usually used. As the photoradical generator, a known compound that can be used for this purpose can be used. Examples include benzophenone, benzoin methyl ether, benzoin propyl ether, diethoxyacetophenone, 1-hydroxycyclohexyl phenyl ketone, 2,6-dimethylbenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, and the like. Among these, benzophenone and 2,4,6-trimethylbenzoyldiphenylphosphine oxide are preferable. These photopolymerization initiators may be used alone or in combination of two or more.

  The amount of the photopolymerization initiator used is 0.001 part by weight or more, preferably 0.01 part by weight or more, more preferably 0, when the total amount of radically polymerizable compounds in the curable composition is 100 parts by weight. .05 parts by weight or more. The upper limit is usually 1 part by weight or less, preferably 0.5 part by weight or less, more preferably 0.1 part by weight or less. When the addition amount of the photopolymerization initiator is too large, the polymerization proceeds rapidly, and not only the birefringence of the resulting cured product is increased, but also the hue is deteriorated. As described in Japanese Patent Application Laid-Open No. 2004-352781 as a known technique, when the concentration of the initiator is 5 parts by weight, light cannot reach the opposite side to the ultraviolet irradiation due to the absorption of the initiator. An uncured part is formed. Further, it is colored yellow and the hue is markedly deteriorated. On the other hand, if the amount is too small, the polymerization may not proceed sufficiently even if ultraviolet irradiation is performed.

  Examples of the thermal polymerization initiator include hydroperoxide, dialkyl peroxide, peroxy ester, diacyl peroxide, peroxy carbonate, peroxy ketal, and ketone peroxide. Specifically, benzoyl peroxide, diisopropyl peroxy carbonate, t-butyl peroxy (2-ethylhexanoate) dicumyl peroxide, di-t-butyl peroxide, t-butyl peroxybenzoate, t-butyl hydroperoxide Side, diisopropylbenzene hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide and the like can be used. When thermal polymerization is initiated at the time of light irradiation, it becomes difficult to control the polymerization. Therefore, these thermal polymerization initiators preferably have a 1 minute half-life temperature of 120 ° C. or higher. These polymerization initiators may be used alone or in combination of two or more.

  Hereinafter, the present invention will be described more specifically with reference to production examples, examples, and comparative examples. However, the present invention is not limited to the following examples unless it exceeds the gist.

  In addition, the measuring method of the chemical modification rate of the cellulose nonwoven fabric of this invention, a porosity, a moisture content, the cellulose content of the composite material using a cellulose nonwoven fabric, haze, YI, and a linear expansion coefficient is as follows.

これを解いていくと、以下の通りである。

[Chemical modification rate of cellulose nonwoven fabric]
0.05 g of cellulose nonwoven fabric is precisely weighed, and 6 ml of methanol and 2 ml of distilled water are added thereto. This is stirred at 60-70 ° C. for 30 minutes, and then 10 ml of 0.05N aqueous sodium hydroxide solution is added. The mixture is stirred at 60 to 70 ° C. for 15 minutes and further stirred at room temperature for one day. This is titrated with 0.02N aqueous hydrochloric acid using phenolphthalein.
Here, from the amount Z (ml) of the 0.02N hydrochloric acid aqueous solution required for the titration, the number of moles Q of the substituent introduced by chemical modification is obtained by the following formula.
Q (mol) = 0.05 (N) × 10 (ml) / 1000
−0.02 (N) × Z (ml) / 1000
The relationship between the number of moles Q of the substituent and the chemical modification rate X (mol%) is calculated by the following formula (cellulose = (C ₆ O ₅ H ₁₀ ) _n = (162.14) _n , repetition Number of hydroxyl groups per unit = 3, molecular weight of OH = 17). In the following, T is the molecular weight of the substituent.

Solving this, it is as follows.

[Porosity of cellulose nonwoven fabric]
It calculated | required by the following formula from the area, thickness, and weight of the cellulose nonwoven fabric.
Porosity (volume%) = {(1-B / (M × A × t)} × 100
Here, A is the area (cm ² ) of the nonwoven fabric, t (cm) is the thickness, B is the weight (g) of the nonwoven fabric, M is the density of cellulose, and M = 1.5 g / cm ³ is assumed in the present invention. To do. The film thickness of the cellulose nonwoven fabric was measured at 10 points for various positions of the nonwoven fabric using a film thickness meter (IP65 manufactured by Mitutoyo Co., Ltd.), and the average value was adopted.

[Moisture content of cellulose nonwoven fabric]
The cellulose nonwoven fabric is conditioned at a temperature of 23 ° C. and a humidity of 50% for 48 hours or more, and the temperature is increased from room temperature to 600 ° C. at a rate of 10 ° C./minute using TG-DTA (simultaneous differential thermogravimetric measurement device). The weight loss rate (%) at 200 ° C. at that time was defined as the moisture content.

[Thermal decomposition temperature of cellulose nonwoven fabric]
The cellulose non-woven fabric was conditioned at a temperature of 23 ° C. and a humidity of 50% for 48 hours or more, and the temperature was increased from room temperature to 600 ° C. at a rate of 10 ° C./min under nitrogen using a TG-DTA (differential thermogravimetric simultaneous measurement device). The intersection of tangents obtained from the TG at that time was taken as the decomposition temperature.

[Haze of composite materials using cellulose nonwoven fabric]
The haze value by C light was measured using a Suga Test Instruments haze meter.

[YI value of composite material using cellulose non-woven fabric]
The YI value was measured using a color computer manufactured by Suga Test Instruments.

[Linear expansion coefficient of composite materials using cellulose nonwoven fabric]
The composite material was cut into 3 mm width × 40 mm length with a laser cutter.
This was stretched using a TII TMA120 made of SII at a chucking distance of 20 mm, a load of 10 g, and a nitrogen atmosphere from room temperature to 180 ° C. at 5 ° C./min. And then from 180 ° C. to 25 ° C. at 5 ° C./min. At 25 ° C. and then from 25 ° C. to 180 ° C. at 5 ° C./min. The linear expansion coefficient was determined from the measured value from 60 ° C. to 100 ° C. during the second temperature increase.

<Production Example 1>
Wood flour (Miyashita Wood Co., Ltd., Yonematsu 100) was degreased with a 2% by weight aqueous solution of sodium carbonate at 80 ° C for 6 hours. This was washed with demineralized water and then delignified with sodium chlorite under acetic acid acidity at 80 ° C. for 5.5 hours. After washing with desalted water, it was further immersed in a 5% by weight aqueous solution of potassium hydroxide for 16 hours to dehemicellulose. After washing with demineralized water, the suspension was made into a 0.5 wt% water suspension and passed through an ultrahigh pressure homogenizer (Ultimizer manufactured by Sugino Machine) 10 times at 245 MPa.

<Example 1>
The cellulose dispersion obtained in Production Example 1 was diluted with water to a concentration of 0.13% by weight and 150 g was put into a 90 mm diameter filter using PTFE having a pore diameter of 1 μm, so that the solid content became about 5% by weight. By the way, 30 ml of 2-propanol was added and replaced. Thereafter, it was press-dried at 120 ° C. and 0.14 MPa for 5 minutes to obtain a white cellulose nonwoven fabric.
This cellulose nonwoven fabric was impregnated with 100 ml of acetic anhydride and heated at 90 ° C. for 7 hours. Thereafter, it was thoroughly washed with distilled water, and finally immersed in 2-propanol for 10 minutes, and then press-dried at 120 ° C. and 0.14 MPa for 5 minutes to obtain a 45 μm thick acetylated cellulose nonwoven fabric. The chemical modification rate of this nonwoven fabric was 16 mol%. The porosity was 36% by volume. Moreover, it was 1.8% when the moisture content of this cellulose nonwoven fabric was measured. The thermal decomposition temperatures were as shown in Table 1.
From SEM observation of this cellulose nonwoven fabric, it was confirmed that fibers having a fiber diameter of 500 nm or more were not contained. Moreover, the average fiber diameter of 20 places extracted arbitrarily was 14 nm. The nonwoven fabric had a YI value of 11.4.

This non-woven fabric was mixed with 96 parts by weight of bis (methacryloyloxymethyl) tricyclo [5.2.1.0 ^2,6 ] decane, ⁶ parts by weight of pentaerythritol tetrakis (β-thiopropionate), 2,4,6-trimethyl. A mixed solution of 0.05 parts by weight of benzoyldiphenylphosphine oxide (Lucirin TPO manufactured by BASF) and 0.05 parts by weight of benzophenone was impregnated and left overnight under reduced pressure. This was sandwiched between two glass plates and irradiated under an irradiance of 400 mW / cm ² at a line speed of 7 m / min using an electrodeless mercury lamp (“D bulb” manufactured by Fusion UV Systems). The irradiation dose at this time was 0.12 J / cm ² . This operation was performed twice by inverting the glass surface. The temperature of the glass surface after ultraviolet irradiation was 25 ° C.
Next, irradiation was performed under an irradiance of 1900 mW / cm ^{2 at} a line speed of 2 m / min. The radiation dose at this time was 2.7 J / cm ² . This operation was performed 8 times by inverting the glass surface. The temperature of the glass surface after ultraviolet irradiation was 44 ° C. The irradiation dose was 21.8 J / cm ² . After the ultraviolet irradiation, the glass plate was removed and heated in a vacuum oven at 190 ° C. for 4 hours to obtain a composite material. In addition, the irradiance of ultraviolet rays was measured at 23 ° C. by using an ultraviolet ray illuminance meter “UV-M02” manufactured by Oak Seisakusho and using an attachment “UV-35”.
Table 1 shows the physical properties of this composite material.

  The composite material was cut into a 3 mm width × 40 mm length by a laser cutter. This was subjected to DMA (dynamic viscoelasticity) measurement in a tensile mode using a DMS6100 manufactured by SII, and a storage elastic modulus E ′ (unit: GPa) at 10 mm between chucks, a frequency of 10 Hz, and 23 ° C. was measured. 1 GPa.

<Example 2>
An acetylated cellulose nonwoven fabric having a thickness of 57 μm was obtained in the same manner as in Example 1 except that the reaction temperature when chemically modifying the cellulose nonwoven fabric was changed to 100 ° C. The chemical modification rate of this nonwoven fabric was 32 mol%. The porosity was 38% by volume.
This nonwoven fabric was composited in the same manner as in Example 1 to obtain a composite material. Table 1 shows the physical properties of the nonwoven fabric and the composite material.

<Example 3>
A 51 μm thick acetylated cellulose nonwoven fabric was obtained in the same manner as in Example 1 except that the reaction temperature when chemically modifying the cellulose nonwoven fabric was 60 ° C. and the reaction time was changed to 3.5 hours. The chemical modification rate of this nonwoven fabric was 8.3 mol%. The porosity was 44% by volume.
This nonwoven fabric was composited in the same manner as in Example 1 to obtain a composite material. Table 1 shows the physical properties of the nonwoven fabric and the composite material.

<Example 4>
In Production Example 1, cellulose that had been dehemicellulosed and washed with demineralized water was dehydrated by filtration. This was dispersed in acetic acid and filtered three times to replace water with acetic acid. To 1 g of cellulose, 50 ml of toluene, 40 ml of acetic acid, and 60 wt% perchloric acid aqueous solution 0.2 ml were mixed, and after adding cellulose substituted with acetic acid there, 1 ml of acetic anhydride was added and reacted for 1 hour with stirring. After the reaction, the reaction solution was filtered and washed with methanol and demineralized water in this order to obtain a 0.5% by weight aqueous suspension.

The above-mentioned water suspension is carried out at a rotational speed of 1500 rpm at a position tightened by 80 μm from the position where the upper and lower stone dies are in contact with the use of a GC6-80 stone mortar using a mortar grinder Supermass colloider MKCA6-2. The operation of introducing the liquid from the raw material inlet and passing it through the stone mill was repeated twice. Further, it was passed through an ultrahigh pressure homogenizer (Sugino Machine Ultimate) twice at 150 MPa and 10 times at 245 MPa. The cellulose dispersion thus refined is diluted with water to a concentration of 0.13% by weight, and 150 g is put into a 90 mm diameter filter using PTFE having a pore diameter of 1 μm, and the solid content is about 5% by weight. Then, 30 ml of 2-propanol was added and replaced. Thereafter, it was press-dried at 120 ° C. and 0.14 MPa for 5 minutes to obtain a white acetylated cellulose nonwoven fabric. The nonwoven fabric had a thickness of 48 μm and a chemical modification rate of 8.3 mol%. The porosity was 45% by volume.
This nonwoven fabric was composited in the same manner as in Example 1 to obtain a composite material. Table 1 shows the physical properties of the nonwoven fabric and the composite material.

<Example 5>
A 50 μm thick acetylated cellulose nonwoven fabric was obtained in the same manner as in Example 4 except that the amount of acetic anhydride added to 1 g of cellulose was changed to 1.5 ml. The chemical modification rate of this nonwoven fabric was 18.7 mol%. The porosity was 47% by volume.
This nonwoven fabric was composited in the same manner as in Example 1 to obtain a composite material. Table 1 shows the physical properties of the nonwoven fabric and the composite material.

<Example 6>
In Example 4, after the cellulose dispersion after passing the ultrahigh pressure homogenizer 10 times at 245 MPa to 0.25 wt% with water, SMT ultrasonic homogenizer UH-600S (frequency 20 kHz, output 224 W) was used. The ultrasonic treatment was performed under the above conditions.
Using a 36 mmφ straight tip (made of titanium alloy), tuning was performed with the output volume 8, and ultrasonic treatment was performed at 50% intermittent operation for 60 minutes at the optimum tuning position. 50% intermittent operation refers to an operation in which an ultrasonic wave is oscillated for 0.5 seconds and then rested for 0.5 seconds. The cellulose dispersion was cooled from the outside of the processing vessel with cold water at 5 ° C., and the temperature of the dispersion was kept at 15 ° C. ± 5 ° C., and the cellulose dispersion was treated with stirring with a magnetic stirrer.

The ultrasonically treated cellulose dispersion was further diluted to 0.13% by weight with water and then centrifuged. HimacCR22G manufactured by Hitachi Koki Co., Ltd. was used as the centrifuge, and R20A2 was used as the angle rotor. Eight 50 ml centrifuge tubes were installed at an angle of 34 degrees from the rotation axis. The amount of the cellulose dispersion put in one centrifuge tube was 30 ml. Centrifugation was performed at 18000 rpm for 30 minutes, and the supernatant was collected.
This supernatant was filtered in the same manner as in Example 4 to obtain a white acetylated cellulose nonwoven fabric. The nonwoven fabric had a thickness of 44 μm and a chemical modification rate of 9.0 mol%. The porosity was 46% by volume.
This nonwoven fabric was composited in the same manner as in Example 1 to obtain a composite material. Table 1 shows the physical properties of the nonwoven fabric and the composite material.

<Comparative Example 1 (Further Examination of Example 6 of JP 2007-51266 A)>
The cellulose dispersion liquid of Production Example 1 was diluted with water to a concentration of 0.2% by weight, 100 g was put into a 90 mm diameter filter using PTFE having a pore diameter of 1 μm, filtered, and dried with a blower dryer at 55 ° C. This cellulose nonwoven fabric was impregnated with 100 ml of acetic anhydride and heated at 120 ° C. for 14 hours. Then, after washing with methanol, running water and distilled water, it was dried under reduced pressure at 60 ° C. for 1 hour to obtain an acetylated cellulose nonwoven fabric having a thickness of 38 μm. The chemical modification rate of this nonwoven fabric was 4.3 mol%. The porosity was 31% by volume.
This nonwoven fabric was composited in the same manner as in Example 1 to obtain a composite material. Table 1 shows the physical properties of the nonwoven fabric and the composite material.

<Comparative example 2>
The cellulose dispersion obtained in Production Example 1 was diluted with water to a concentration of 0.2% by weight, and 100 g was put into a 90 mm diameter filter using PTFE having a pore diameter of 1 μm and filtered, and 120 minutes at 120 ° C. and 2 MPa for 5 minutes. The cellulose nonwoven fabric was obtained by press drying.
This cellulose nonwoven fabric was impregnated with 100 ml of acetic anhydride and heated at 120 ° C. for 14 hours. Thereafter, it was thoroughly washed with distilled water and finally immersed in 2-propanol for 10 minutes, and then press-dried at 120 ° C. and 2 MPa for 5 minutes to obtain a 39 μm thick acetylated cellulose nonwoven fabric. The chemical modification rate of this nonwoven fabric was 13 mol%. The porosity was 25% by volume.
This nonwoven fabric was composited in the same manner as in Example 1 to obtain a composite material. Table 1 shows the physical properties of the nonwoven fabric and the composite material.

  As can be seen from the results of Comparative Examples 1 and 2, when the porosity of the cellulose nonwoven fabric is low, the resin is difficult to be impregnated, resulting in high haze and poor transparency. Moreover, when the chemical modification rate of the cellulose nonwoven fabric was low as shown in Comparative Example 1, the YI value of the composite material was high. On the other hand, as shown in Examples 1 to 6, by controlling the chemical modification rate and porosity of the cellulose nonwoven fabric, the haze is low, that is, the transparency is high, the YI value is low, and the linear expansion coefficient is also low. A composite material could be obtained.

Claims (7)

  A cellulose nonwoven fabric that is chemically modified and has a chemical modification rate of 8 to 65 mol% with respect to the total hydroxyl groups of cellulose and a porosity of 35% by volume or more.   The cellulose nonwoven fabric according to claim 1, wherein the chemical modification rate is 8 to 50 mol%.   The cellulose nonwoven fabric according to claim 1 or 2, wherein the porosity is 60% by volume or less.   The method for producing a cellulose nonwoven fabric according to any one of claims 1 to 3, wherein the cellulose is chemically modified after being made into a nonwoven fabric.   The method for producing a cellulose nonwoven fabric according to any one of claims 1 to 3, wherein the cellulose is chemically modified and then made into a nonwoven fabric.   6. The method for producing a cellulose nonwoven fabric according to claim 4 or 5, wherein the cellulose is made into a nonwoven fabric after being washed with an organic solvent.   The composite material containing the cellulose nonwoven fabric as described in any one of Claims 1 thru | or 3, and resin other than a cellulose.