Resin composition

Abstract

To provide a resin composition which is excellent in mechanical strength, for example, improves elongation at a shear adhesive test, when being used in bonding of a metal member of a structure.SOLUTION: A resin composition contains (A) a modified cellulose fiber, (B) an urethane-modified epoxy resin, and (C) an epoxy resin other than the urethane-modified epoxy resin.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a resin composition.

Background Art

[0002] In recent years, technologies with less environmental impact have come into the spotlight. Under such a technical background, materials using cellulose fibers, which are biomass abundantly present in nature, have attracted attention.

[0003] For example, Patent Document 1 discloses an adhesive composition containing a water-insoluble resin, fine cellulose fibers containing ionic groups, and / or fine cellulose fiber composites obtained by bonding a modifying group to fine cellulose fibers containing ionic groups. In addition, Patent Document 2 discloses an adhesive composition characterized by containing microfibrillar cellulose and a matrix resin that satisfy the following conditions (A) to (E). (A) The number average fiber diameter is 2 nm or more and 500 nm or less (B) The average aspect ratio is 10 or more and 1000 or less (C) It has a cellulose I-type crystal structure (D) It has an anionic functional group (E) A specific polyetheramine is bonded to part or all of the anionic functional groups described in (D).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] Adhesives have different required performances depending on the physical properties of the object to be adhered. The present invention relates to providing a resin composition that, when used for bonding metal members of a structure or the like, has excellent mechanical strength, for example, improved elongation in a shear adhesion test.

Means for Solving the Problems

[0006] The present invention relates to the following [1] to

[20] . [1] A resin composition comprising (A) a modified cellulose fiber, (B) a urethane-modified epoxy resin, and (C) an epoxy resin other than the urethane-modified epoxy resin. [2] The composition according to [1] above, wherein the (A) modified cellulose fiber has a cellulose I-type crystal structure and an average fiber diameter of 1 nm or more and 300 nm or less. [3] The (A) modified cellulose fiber is one in which a modifying group and an anion-modified cellulose fiber are bonded, and the modifying group contains at least one selected from the group consisting of (i) a hydrocarbon group having 3 or more carbon atoms, (ii) a silicone chain, and (iii) an alkylene oxide chain. The composition according to [1] or [2] above. [4] The composition according to [3] above, wherein the modifying group and the anionic group of the anion-modified cellulose fiber are bonded via an ionic bond and / or a covalent bond. [5] The epoxy resin other than the (C) urethane-modified epoxy resin is at least one selected from the group consisting of bisphenol-type epoxy resin, rubber-modified epoxy resin, alicyclic epoxy resin, glycidylamine-type epoxy resin, polysulfide-modified epoxy resin, chelate-modified epoxy resin, trisphenolmethane-type epoxy resin, naphthalene-type epoxy resin, dicyclopentadiene-modified epoxy resin, aliphatic polyol or an epoxidized product of these derivatives, polyether-modified epoxy resin, polyfunctional aromatic epoxy resin, and hydrogenated bisphenol-type epoxy resin. The composition according to any one of [1] to [4] above. 〔6〕 The composition according to any one of 〔1〕 to 〔5〕 above, wherein the content of (B) urethane-modified epoxy resin in the composition is 1% by mass or more and less than 80% by mass, and the content of (C) epoxy resin other than urethane-modified epoxy resin is 1% by mass or more and less than 80% by mass. 〔7〕 The composition according to any one of 〔1〕 to 〔6〕 above, which is obtained by mixing a mixture of (A) modified cellulose fiber and (B) urethane-modified epoxy resin with (C) epoxy resin other than urethane-modified epoxy resin. 〔8〕 The composition according to any one of 〔1〕 to 〔6〕 above, which is obtained by mixing a mixture of (B) urethane-modified epoxy resin and (C) epoxy resin other than urethane-modified epoxy resin with (A) modified cellulose fiber. 〔9〕 The composition according to any one of 〔1〕 to 〔6〕 above, which is obtained by mixing a mixture of (A) modified cellulose fiber and (C) epoxy resin other than urethane-modified epoxy resin with (B) urethane-modified epoxy resin. 〔10〕 An adhesive comprising the composition according to any one of 〔1〕 to 〔9〕 above.

[0007] 〔11〕 The adhesive according to 〔10〕 above, wherein the adhesive is a structural adhesive. 〔12〕 The adhesive according to 〔10〕 or 〔11〕 above, further comprising a filler other than (A) modified cellulose fiber. 〔13〕 The adhesive according to any one of 〔10〕 to 〔12〕 above, which is used for bonding vehicle assembly parts. 〔14〕 A method for bonding vehicle assembly parts, comprising a step of bonding vehicle assembly parts using the adhesive according to any one of 〔10〕 to 〔13〕 above. 〔15〕 In a method for producing a resin composition containing (B) urethane-modified epoxy resin and (C) epoxy resin other than urethane-modified epoxy resin, Step 1: A step of mixing (A) modified cellulose fiber and (B) urethane-modified epoxy resin, and Step 2: A step of mixing the mixture obtained in Step 1 with (C) epoxy resin other than urethane-modified epoxy resin A method for producing a resin composition, comprising the above steps. 〔16〕In a method for producing a resin composition containing (B) a urethane-modified epoxy resin and (C) an epoxy resin other than the urethane-modified epoxy resin, a production method having the following step 3 or step 4. Step 3: A step of mixing (A) modified cellulose fiber, (B) a urethane-modified epoxy resin, and (C) an epoxy resin other than the urethane-modified epoxy resin Step 4: A step of mixing (B) a urethane-modified epoxy resin and (C) an epoxy resin other than the urethane-modified epoxy resin (step 4-1), and mixing the resulting composition with (A) modified cellulose fiber (step 4-2). 〔17〕In a method for producing a resin composition containing (B) a urethane-modified epoxy resin and (C) an epoxy resin other than the urethane-modified epoxy resin, Step 5: A step of mixing (A) modified cellulose fiber and (C) an epoxy resin other than the urethane-modified epoxy resin Step 6: A step of mixing the composition obtained in step 5 with (B) a urethane-modified epoxy resin A method for producing a resin composition, comprising the above steps. 〔18〕A method for improving the elongation at break of a structural adhesive, which has a step of mixing (A) modified cellulose fiber and (B) a urethane-modified epoxy resin. 〔19〕An adhesive kit comprising a container containing the adhesive according to any one of the above items 〔10〕 to 〔13〕. 〔20〕A first container containing the composition according to any one of the above items 〔1〕 to 〔9〕, A second container containing a curing agent An adhesive kit comprising the above components.

Advantages of the Invention

[0008] According to the present invention, when used for adhering metal members of a structure, etc., a resin composition excellent in mechanical strength can be provided.

Embodiments for Carrying Out the Invention

[0009] Although the detailed mechanism by which the resin composition of the present invention exhibits such an effect is unknown, it is presumed that the modified cellulose fiber is present at the interface between the object to be adhered and the resin, so that even if the smoothness of the adhesion surface of the object to be adhered (for example, metal and / or plastic) is somewhat low, the adhesiveness of the resin to the adhesion surface is improved and the elongation is improved.

[0010] The resin composition of the present invention contains (A) a modified cellulose fiber, (B) a urethane-modified epoxy resin, and (C) an epoxy resin other than the urethane-modified epoxy resin.

[0011] [(A) Modified cellulose fiber] The modified cellulose fiber in the present invention is one in which a modifying group having a specific structure is bonded to the cellulose fiber. The modifying group is preferably bonded to a part or all of the hydroxy groups of the cellulose fiber or to the carboxy group obtained by converting the group (-CH2OH) at the C6 position of the glucose unit constituting the cellulose fiber into a carboxy group.

[0012] (Anionic modified cellulose fiber) As the cellulose fiber to which the modifying group is bonded, an anionic modified cellulose fiber is preferable from the viewpoint of the ease of bonding of the modifying group. An anionic modified cellulose fiber is a cellulose fiber having one or more groups selected from the group consisting of anionic groups such as a carboxy group, a (sub)phosphonic acid group, and a sulfonic acid group in the molecule. From the viewpoints of availability and effect, an anionic modified cellulose fiber having a carboxy group as the anionic group is preferable, and an anionic modified cellulose fiber (referred to as "oxidized cellulose fiber") in which the group (-CH2OH) at the C6 position of the glucose unit constituting the cellulose fiber is selectively converted into a carboxy group is more preferable. The ion (counter ion) paired with the anionic group is preferably a proton.

[0013] As for the anionic group content in the anionic modified cellulose fiber, from the viewpoints of stable introduction of the modifying group and increasing the adhesion strength by introducing the modifying group, it is preferably 0.1 mmol / g or more, more preferably 0.4 mmol / g or more, still more preferably 0.6 mmol / g or more, still more preferably 0.7 mmol / g or more, still more preferably 0.8 mmol / g or more. Further, from the viewpoint of improving handleability, it is preferably 3 mmol / g or less, more preferably 2.5 mmol / g or less, more preferably 2 mmol / g or less, more preferably 1.9 mmol / g or less, still more preferably 1.8 mmol / g or less, more preferably 1.7 mmol / g or less, still more preferably 1.5 mmol / g or less. The "anionic group content" means the total amount of anionic groups in glucose constituting the cellulose fiber, and specifically, it is measured by the method described in the examples below.

[0014] The bonding of the modifying group to the anionic group of the anionic modified cellulose fiber means that the modifying group is bonded to the anionic group, preferably the carboxy group, which the anionic modified cellulose fiber has. Examples of the bonding mode between the modifying group and the anionic group include ionic bond and / or covalent bond. Examples of the covalent bond include, for example, amide bond, ester bond, and urethane bond, and preferably an amide bond. Therefore, as a preferred embodiment of the modified cellulose fiber in the present invention, there is one in which the modifying group is bonded to the anionic group of the anionic modified cellulose fiber via an ionic bond and / or a covalent bond.

[0015] (Modifying group) Examples of the modifying group include those containing (i) a hydrocarbon group having 3 or more carbon atoms, (ii) a silicone chain, and (iii) an alkylene oxide chain. These modifying groups may be bonded (introduced) to the cellulose fiber alone or in combination of two or more.

[0016] (i) Hydrocarbon group having 3 or more carbon atoms Examples of hydrocarbon groups having 3 or more carbon atoms include monovalent hydrocarbon groups such as linear saturated hydrocarbon groups, linear unsaturated hydrocarbon groups, cyclic saturated hydrocarbon groups, and (heterocyclic) aromatic hydrocarbon groups. From the viewpoint of enhancing the adhesive strength when the composition is used as an adhesive, the number of carbon atoms of the hydrocarbon group is 3 or more, preferably 8 or more, more preferably 10 or more. From the same viewpoint, it is preferably 30 or less, more preferably 22 or less, and even more preferably 18 or less. The hydrocarbon group may have a substituent described later, and a part of the hydrocarbon group may be substituted with a nitrogen-hydrogen group.

[0017] The linear saturated hydrocarbon group preferably has 3 to 30 carbon atoms. Specific examples include, for example, propyl group, isopropyl group, butyl group, sec-butyl group, tert-butyl group, isobutyl group, pentyl group, tert-pentyl group, isopentyl group, hexyl group, isohexyl group, heptyl group, octyl group, 2-ethylhexyl group, nonyl group, decyl group, dodecyl group, tridecyl group, tetradecyl group, octadecyl group, docosyl group, octacosanyl group, etc.

[0018] The linear unsaturated hydrocarbon group preferably has 3 to 30 carbon atoms. Specific examples include, for example, propenyl group, butenyl group, isobutenyl group, isoprenyl group, pentenyl group, hexenyl group, heptenyl group, octenyl group, nonenyl group, decenyl group, dodecenyl group, tridecenyl group, tetradecenyl group, octadecenyl group.

[0019] The cyclic saturated hydrocarbon group preferably has 3 to 20 carbon atoms. Specific examples include, for example, cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclononyl group, cyclodecyl group, cyclododecyl group, cyclotridecyl group, cyclotetradecyl group, cyclooctadecyl group, etc.

[0020] Examples of the aromatic hydrocarbon group include an aryl group and an aralkyl group. The aryl group and the aralkyl group may be either unsubstituted or substituted with substituents described later. Examples of the heterocyclic aromatic hydrocarbon group include an imidazole group.

[0021] The total number of carbon atoms of the aryl group is preferably 6 or more and 24 or less. Specific examples of the aryl group include, for example, a phenyl group, a naphthyl group, an anthryl group, a phenanthryl group, a biphenyl group, a triphenyl group, a terphenyl group, and groups in which these groups are substituted with substituents described later.

[0022] The total number of carbon atoms of the aralkyl group is preferably 7 or more and 24 or less. Specific examples of the aralkyl group include, for example, a benzyl group, a phenethyl group, a phenylpropyl group, a phenylpentyl group, a phenylhexyl group, a phenylheptyl group, a phenyloctyl group, and groups in which these groups are substituted with substituents described later. The total number of carbon atoms of the imidazole group is preferably 3 or more and 24 or less. Specific examples of the imidazole group include, for example, an imidazole group, a methylimidazole group, an ethylimidazole group, a propylimidazole group, a 2-phenylimidazole group, a benzimidazole group, and groups in which these groups are substituted with substituents.

[0023] (ii) Silicone chain The silicone chain is a monovalent group having a siloxane bond as a main chain, and may further have an alkylene group. The silicone chain may have substituents described later.

[0024] (iii) Alkylene oxide chain The alkylene oxide chain is a structure containing a (co)polymer of ethylene oxide (EO) or propylene oxide (PO), preferably a structure containing a polymer of EO (EO chain), a structure containing a polymer of PO (PO chain), and one or more structures selected from the group consisting of a structure containing a copolymer in which EO and PO are polymerized randomly or in blocks ((EO / PO) chain). A hydrocarbon group may be further bonded to the alkylene oxide chain.

[0025] Examples of the alkylene oxide chain include the following formula:

[0026]

Chemical formula

[0027] (In the formula, R 1 represents a hydrogen atom, a hydrocarbon group having 1 to 6 carbon atoms, or a -CH2CH(CH3)NH2 group. EO and PO are present randomly or in blocks, a is 0 or a positive number indicating the average number of added moles of EO, and b is 0 or a positive number indicating the average number of added moles of PO. However, the case where both a and b are 0 is excluded.) The group represented by the formula is mentioned.

[0028] In the above formula, a represents the average number of added moles of EO. From the viewpoints of availability and affinity with the resin, it is preferably 0 or more, more preferably 1 or more, still more preferably 2 or more, and from the same viewpoints, it is preferably 100 or less, more preferably 70 or less.

[0029] In the above formula, b represents the average number of added moles of PO. From the viewpoint of affinity with the resin, it is preferably 0 or more, more preferably 1 or more, still more preferably 3 or more, and from the viewpoint of availability, it is preferably 50 or less, more preferably 40 or less.

[0030] R in the above formula 1Specific examples of the hydrocarbon group having 1 to 6 carbon atoms include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, an isobutyl group, a pentyl group, a tert-pentyl group, an isopentyl group, a hexyl group, an isohexyl group, and the like.

[0031] The formula weight (molecular weight) of the alkylene oxide chain is preferably 500 or more, more preferably 1,000 or more. On the other hand, it is preferably 10,000 or less, more preferably 7,000 or less. The formula weight of the alkylene oxide chain can be determined by calculation from the average addition mole number when producing an amine compound having the alkylene oxide chain described below.

[0032] The content rate (mol%) of PO in the (EO / PO) chain is preferably 1 mol% or more, more preferably 5 mol% or more, from the viewpoint of enhancing the adhesive strength. On the other hand, from the same viewpoint, it is preferably 100 mol% or less, more preferably 95 mol% or less, still more preferably 90 mol% or less. The content rate of PO in the (EO / PO) chain can be determined by calculation from the average addition mole number when producing an amine compound having the alkylene oxide chain described below. The alkylene oxide chain may have the following substituents.

[0033] (iv) Further substituents Note that the modifying group may further have a substituent. Examples of the substituent include alkoxy groups having 1 to 6 carbon atoms such as methoxy group, ethoxy group, propoxy group, isopropoxy group, butoxy group, isobutoxy group, sec-butoxy group, tert-butoxy group, pentyloxy group, isopentyloxy group, hexyloxy group; alkoxy-carbonyl groups having 1 to 6 carbon atoms of alkoxy groups such as methoxycarbonyl group, ethoxycarbonyl group, propoxycarbonyl group, isopropoxycarbonyl group, butoxycarbonyl group, isobutoxycarbonyl group, sec-butoxycarbonyl group, tert-butoxycarbonyl group, pentyloxycarbonyl group, isopentyloxycarbonyl group; halogen atoms such as fluorine atom, chlorine atom, bromine atom, iodine atom; acyl groups having 1 to 6 carbon atoms such as acetyl group, propionyl group; aralkyl group; aralkyloxy group; alkylamino groups having 1 to 6 carbon atoms; dialkylamino groups having 1 to 6 carbon atoms of the alkyl group; and hydroxy group.

[0034] [Method for producing modified cellulose fiber] The modified cellulose fiber can be produced, for example, by introducing an anionic group into the raw material cellulose fiber to prepare an anion-modified cellulose fiber (step a), and then bonding a modifying group to the anionic group of the anion-modified cellulose fiber (step b).

[0035] (Step a) Raw material cellulose fiber As the cellulose fiber which is the raw material of the anion-modified cellulose fiber, natural cellulose is preferable from the environmental aspect. Examples thereof include wood pulp such as softwood pulp and hardwood pulp; cotton-based pulp such as cotton linter and cotton lint; non-wood pulp such as wheat straw pulp and bagasse pulp; and bacterial cellulose. These can be used alone or in combination of two or more.

[0036] The average fiber diameter of the raw material cellulose fiber is not particularly limited, but from the viewpoints of handleability and cost, it is preferably 5 μm or more, more preferably 7 μm or more, and from the same viewpoints, it is preferably 500 μm or less, more preferably 300 μm or less. The average fiber diameter of the raw material cellulose fiber is determined by the method described in the examples below.

[0037] Also, the average fiber length of the raw material cellulose fiber is not particularly limited, but from the viewpoints of availability and cost, it is preferably 5 μm or more, more preferably 25 μm or more, and from the same viewpoints, it is preferably 5,000 μm or less, more preferably 3,000 μm or less. The average fiber length of the raw material cellulose fiber can be measured according to the method described in the examples below.

[0038] Treatment method (1) When introducing a carboxy group as an anionic group into cellulose fiber As a method for introducing a carboxy group into cellulose fiber, for example, a method of oxidizing the hydroxy group of cellulose fiber to convert it into a carboxy group, or a method of reacting at least one selected from the group consisting of a compound having a carboxy group, an acid anhydride of a compound having a carboxy group, and derivatives thereof with the hydroxy group of cellulose fiber can be mentioned.

[0039] As a method for oxidizing the hydroxy group of cellulose fiber, for example, the method described in JP-A-2015-143336 or JP-A-2015-143337, in which 2,2,6,6-tetramethyl-1-piperidine-N-oxyl (TEMPO) is used as a catalyst, and an oxidizing agent such as sodium hypochlorite and a bromide such as sodium bromide are reacted with the raw material cellulose fiber. By oxidizing cellulose fiber using TEMPO as a catalyst, the group at the C6 position of glucose in the cellulose fiber structural unit is selectively converted into a carboxy group, and the above-mentioned oxidized cellulose fiber can be obtained.

[0040] The compound having a carboxy group for use in introducing a carboxy group into cellulose fibers is not particularly limited, and specifically, halogenated acetic acids can be mentioned. Examples of the halogenated acetic acid include chloroacetic acid and the like. The acid anhydrides of compounds having a carboxy group and their derivatives for use in introducing a carboxy group into cellulose fibers are not particularly limited, and examples thereof include acid anhydrides of dicarboxylic acid compounds such as maleic anhydride, succinic anhydride, phthalic anhydride, and adipic anhydride, imidized products of acid anhydrides of compounds having a carboxy group, and derivatives of acid anhydrides of compounds having a carboxyl group. These compounds may be substituted with a hydrophobic group.

[0041] (2) When introducing a sulfonic acid group or a (sub)phosphoric acid group as an anionic group into cellulose fibers As a method for introducing a sulfonic acid group into cellulose fibers, a method of adding sulfuric acid to cellulose fibers and heating them can be mentioned. As a method for introducing a (sub)phosphoric acid group into cellulose fibers, a method of mixing a powder or aqueous solution of (sub)phosphoric acid or a (sub)phosphoric acid derivative with cellulose fibers in a dry or wet state, or a method of adding an aqueous solution of (sub)phosphoric acid or a (sub)phosphoric acid derivative to a dispersion of cellulose fibers can be mentioned. When these methods are adopted, generally, after mixing or adding a powder or aqueous solution of (sub)phosphoric acid or a (sub)phosphoric acid derivative, dehydration treatment, heat treatment, etc. are performed.

[0042] (Step b) The introduction of a modifying group into the anionic group of an anionic-modified cellulose fiber is achieved by reacting a compound for introducing a modifying group into the anionic group (referred to as a "modifying compound") with the anionic-modified cellulose fiber. As a method for introducing a modifying group, (1) when introducing through an ionic bond, Japanese Patent Application Laid-Open No. 2015-143336 can be referred to, and (2) when introducing through an amide bond, Japanese Patent Application Laid-Open No. 2015-143337 can be referred to. After the completion of Project b, post-treatment may be appropriately carried out to remove unreacted compounds and the like. As the post-treatment method, for example, filtration, centrifugation, dialysis, etc. can be used.

[0043] (1) Mode of introduction via ionic bond When introducing a modifying group via an ionic bond, an anionic modified cellulose fiber and a modifying compound may be mixed, whereby an ionic bond is formed between the anionic group contained in the anionic modified cellulose fiber and the amino group of the modifying compound. Specifically, when using oxidized cellulose fiber as the anionic modified cellulose fiber and a primary amine having the aforementioned modifying group as the modifying compound, as shown in the following formula, the modifying group can be introduced via an ionic bond to the carboxy group at the C6 position of glucose constituting the cellulose fiber (wherein C 6 is the carbon atom at the 6th position of glucose constituting the cellulose fiber, and R is the modifying group.).

[0044]

Chemical formula

[0045] Modifying compound The modifying compound used in this embodiment may be any that can introduce a desired modifying group. Preferably, amine compounds, phosphonium compounds having the aforementioned hydrocarbon group, silicone chain, or alkylene oxide chain, and further guanidino group-containing compounds, etc. are exemplified.

[0046] Amine compound The amine compound is, for example, an amine compound having the aforementioned hydrocarbon group, the aforementioned silicone chain, or the aforementioned alkylene oxide chain as the modifying group, and such hydrocarbon group, etc. is introduced into the anionic modified cellulose fiber via an ionic bond to become the modifying group in the modified cellulose fiber.

[0047] As the amine compound, any of primary amines, secondary amines, tertiary amines, and quaternary ammonium compounds may be used. From the viewpoint of reactivity, the anion component of the quaternary ammonium compound is preferably a halogen ion such as a chlorine ion or a bromine ion, a hydrogen sulfate ion, a perchlorate ion, a tetrafluoroborate ion, a hexafluorophosphate ion, a trifluoromethanesulfonate ion, or a hydroxy ion.

[0048] Amine compound having a hydrocarbon group Specific examples of the amine compound having a hydrocarbon group include, as primary to tertiary amines, for example, diethylamine, triethylamine, propylamine, dipropylamine, butylamine, dibutylamine, hexylamine, 2-ethylhexylamine, dihexylamine, trihexylamine, octylamine, dioctylamine, trioctylamine, dodecylamine, didodecylamine, stearylamine, distearylamine, monoethanolamine, diethanolamine, triethanolamine, oleylamine, aniline, octadecylamine, dimethylbehenylamine, benzylamine, naphthylamine, imidazole, 2-methylimidazole, 2-ethylimidazole, 2-phenylimidazole, 2-ethyl-4-methylimidazole, 2-phenyl-4-methylimidazole, 1-(3-aminopropyl)imidazole, and the like.

[0049] Examples of the quaternary ammonium compound include tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide (TEAH), tetraethylammonium chloride, tetrapropylammonium hydroxide (TPAH), tetrabutylammonium hydroxide (TBAH), tetrabutylammonium chloride, lauryltrimethylammonium chloride, dilauryl dimethyl chloride, stearyltrimethylammonium chloride, distearyl dimethylammonium chloride, cetyltrimethylammonium chloride, and alkylbenzyldimethylammonium chloride.

[0050] An amine compound having a hydrocarbon group can be prepared using a commercially available product or according to a known method.

[0051] An amine compound having a silicone chain Such an amine compound includes, for example, those having a structure in which an amino group is bonded to the skeleton of a silicone chain via an alkylene group or the like. In this specification, such an amine compound may be referred to as "amino-modified silicone". Amino-modified silicone can be prepared using a commercially available product or according to a known method. Only one type of amino-modified silicone may be used, or two or more types may be used.

[0052] As the amino-modified silicone, from the viewpoint of performance, TSF4703 (kinematic viscosity: 1000, amino equivalent: 1600), TSF4708 (kinematic viscosity: 1000, amino equivalent: 2800) manufactured by Momentive Performance Materials, SS-3551 (kinematic viscosity: 1000, amino equivalent: 1600), SF8457C (kinematic viscosity: 1200, amino equivalent: 1800), SF8417 (kinematic viscosity: 1200, amino equivalent: 1700), BY16-209 (kinematic viscosity: 500, amino equivalent: 1800), BY16-892 (kinematic viscosity: 1500, amino equivalent: 2000), BY16-898 (kinematic viscosity: 2000, amino equivalent: 2900), FZ-3760 (kinematic viscosity: 220, amino equivalent: 1600) manufactured by Dow Corning Toray Co., Ltd., KF8002 (kinematic viscosity: 1100, amino equivalent: 1700), KF867 (kinematic viscosity: 1300, amino equivalent: 1700), KF-864 (kinematic viscosity: 1700, amino equivalent: 3800), BY16-213 (kinematic viscosity: 55, amino equivalent: 2700), BY16-853U (kinematic viscosity: 14, amino equivalent: 450) manufactured by Shin-Etsu Chemical Co., Ltd. are preferred. In ( ), the kinematic viscosity indicates the measured value at 25 °C (unit: mm 2 / s), and the unit of the amino equivalent is g / mol.

[0053] An amine compound having an alkylene oxide chain In the amine compound, it is preferable that the alkylene oxide chain and the nitrogen atom of the amine compound are bonded directly or via a linking group. As the linking group, a hydrocarbon group is preferable, and examples thereof include an alkylene group having 1 to 6 carbon atoms, more preferably 1 to 3 carbon atoms. Examples of such an alkylene group include an ethylene group and a propylene group.

[0054] Examples of the amine having an alkylene oxide chain include the following formula (i):

[0055]

Chemical formula

[0056] The compounds represented by are included. R in formula (i) 1 , a and b are the same as R in the formula showing an example of the aforementioned alkylene oxide chain 1 , a and b.

[0057] The amine compound having an alkylene oxide chain can be prepared according to a known method. For example, after adding a desired amount of ethylene oxide and propylene oxide to propylene glycol alkyl ether, the hydroxy group terminal can be aminated. If necessary, the terminal can be made a hydrogen atom by cleaving the alkyl ether with an acid. These production methods can refer to JP-A-3-181448, and details of such amine compounds are described in, for example, Patent No. 6105139.

[0058] Amine compounds having an alkylene oxide chain can, for example, preferably use commercially available products. Specific examples include Jeffamine M-2070, Jeffamine M-2005, Jeffamine M-2095, Jeffamine M-1000, Jeffamine M-600, Surfoamine B200, Surfoamine L100, Surfoamine L200, Surfoamine L207, Surfoamine L300, Surfoamine B-100, XTJ-501, XTJ-506, XTJ-507, XTJ-508, M3000, Jeffamine ED-900, Jeffamine ED-2003, Jeffamine D-2000, Jeffamine D-4000, XTJ-510, Jeffamine T-3000, Jeffamine T-5000, XTJ-502, XTJ-509, XTJ-510, etc. manufactured by Huntsman Corporation, and SUNBRIGHT MEPA-10H, SUNBRIGHT MEPA-20H, SUNBRIGHT MEPA-50H, SUNBRIGHT MEPA-10T, SUNBRIGHT MEPA-12T, SUNBRIGHT MEPA-20T, SUNBRIGHT MEPA-30T, SUNBRIGHT MEPA-40T, etc. manufactured by NOF Corporation. These may be used alone or in combination of two or more.

[0059] Guanidino group-containing compound The guanidino group-containing compound is, for example, a guanidine compound having the aforementioned hydrocarbon group, the aforementioned silicone chain, or the aforementioned alkylene oxide chain as a modifying group, and such a hydrocarbon group or the like is introduced into the anionic modified cellulose fiber via an ionic bond to become a modifying group in the modified cellulose fiber. Examples of the guanidino group-containing compound include diphenylguanidine, ditolylguanidine, 1,2,3-triphenylguanidine, aminoguanidine, and arginine.

[0060] Reaction conditions, etc. From the perspective of reactivity, the amount of the modifying compound used is preferably an amount such that the amino group in the modifying compound is 0.01 mol or more, more preferably 0.1 mol or more, still more preferably 0.5 mol or more, still more preferably 0.7 mol or more, still more preferably 1 mol or more, per 1 mol of the carboxy groups of the oxidized cellulose fiber. From the perspective of product purity, it is preferably an amount of 50 mol or less, more preferably 20 mol or less, still more preferably 10 mol or less. When the modifying compound has a plurality of amino groups, it is used such that the total number of moles of the amino groups becomes the above-mentioned number of moles.

[0061] It is preferable to use a solvent during mixing. As the solvent, it is preferable to select a solvent in which the compound to be used dissolves. For example, methanol, ethanol, isopropanol (IPA), N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), N,N-dimethylacetamide, tetrahydrofuran (THF), acetone, methyl ethyl ketone (MEK), cyclohexanone, ethyl acetate, acetonitrile, dichloromethane, chloroform, toluene, acetic acid, 1-methoxy-2-propanol (PGME), water, etc. can be mentioned, and one of these can be used alone or two or more of them can be used in combination.

[0062] From the perspective of the reactivity of the compound, the temperature during mixing is preferably 0°C or higher, more preferably 5°C or higher, still more preferably 10°C or higher. Also, from the perspective of suppressing the coloring of the modified cellulose fiber, it is preferably 50°C or lower, more preferably 40°C or lower, still more preferably 30°C or lower. The mixing time can be appropriately set according to the types of the compound and the solvent used, but from the perspective of the reactivity of the compound, it is preferably 0.01 hour or more, more preferably 0.1 hour or more, and from the perspective of productivity, it is preferably 48 hours or less, more preferably 24 hours or less.

[0063] (2) Mode of introduction via an amide bond When introducing a modifying group via an amide bond, the anionic modified cellulose fiber and the modifying compound may be mixed in the presence of a known condensing agent, whereby an amide bond is formed between the anionic group contained in the anionic modified cellulose fiber and the amino group of the modifying compound. Specifically, when using oxidized cellulose fiber as the anionic modified cellulose fiber and a primary amine having the aforementioned modifying group as the modifying compound, as shown in the following formula, the modifying group can be introduced via an amide bond to the carboxy group at the C6 position of glucose constituting the cellulose fiber (in the formula, C 6 is the carbon atom at the 6th position of glucose constituting the cellulose fiber, and R is the modifying group.).

[0064]

Chemical formula

[0065] Modifying compound The modifying compound used in this embodiment may be any compound capable of introducing a desired modifying group, and preferably includes an amine compound having the aforementioned hydrocarbon group, alkylene oxide chain, or silicone chain.

[0066] Amine compound The amine compound is, for example, an amine compound having the aforementioned hydrocarbon group, the aforementioned alkylene oxide chain, or the aforementioned silicone chain as the modifying group, and such a hydrocarbon group or the like is introduced into the anionic modified cellulose fiber via an amide bond to become the modifying group in the modified cellulose fiber.

[0067] Examples of the amine compound include primary amines and secondary amines. Specific examples of the amine compound include primary amines and secondary amines among the amine compounds having a hydrocarbon group, an amine compound having an alkylene oxide chain, and an amine compound having a silicone chain, which are exemplified in the aforementioned "(1) Mode of introduction via ionic bond".

[0068] Reaction conditions From the viewpoint of enhancing reactivity and adhesive strength, the amount of the modifying compound used is such that the amino group in the modifying compound is preferably 0.05 mol or more, more preferably 0.1 mol or more, still more preferably 0.2 mol or more, still more preferably 0.3 mol or more, still more preferably 0.5 mol or more, per 1 mol of the carboxy group in the oxidized cellulose fiber. From the viewpoints of product purity and dischargeability, the amount is preferably 50 mol or less, more preferably 20 mol or less, still more preferably 10 mol or less. When the modifying compound has a plurality of amino groups, they are used such that the total number of moles of the amino groups becomes the above-mentioned number of moles.

[0069] The condensing agent is not particularly limited, and examples include the condensing agents described in Synthetic Chemistry Series, Peptide Synthesis (Maruzen Co., Ltd.) P116 or Tetrahedron, 57, 1551 (2001). For example, 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (hereinafter sometimes referred to as "DMT-MM") and the like can be mentioned. Also, it is possible to carry out the reaction only by heat treatment without using a condensing agent.

[0070] In the amidation reaction, a solvent may or may not be used. When using a solvent, it is preferable to select a solvent in which the compound to be used dissolves. Specific examples of the solvent include the solvents exemplified in the above-mentioned "(1) Mode of introduction via ionic bond".

[0071] The reaction time and reaction temperature in the amidation reaction can be appropriately selected according to the types of the compound and solvent used, etc. From the viewpoint of the reaction rate, they are preferably 1 to 24 hours, more preferably 10 to 20 hours. Also, from the viewpoint of reactivity, the reaction temperature is preferably 0°C or higher, more preferably 5°C or higher, still more preferably 10°C or higher. Further, from the viewpoint of product quality such as coloring, it is preferably 200°C or lower, more preferably 80°C or lower, still more preferably 30°C or lower.

[0072] (Miniaturization step) By refining cellulose fibers at any stage of the method for producing modified cellulose fibers (for example, before step a, before step b, and after step b), cellulose fibers on the micrometer scale can be refined to the nanometer scale. It is preferable because the dispersibility in the resin is improved by reducing the average fiber diameter to the nanometer size.

[0073] Known refining treatment methods can be adopted for the refining treatment. For example, when obtaining modified cellulose fibers with an average fiber diameter in the nanometer size, a treatment method using a grinder such as a mas colloid mill or a treatment method using a high-pressure homogenizer or the like in a medium may be carried out.

[0074] Examples of the medium include alcohols having 1 to 6 carbon atoms, preferably 1 to 4 carbon atoms such as water, methanol, ethanol, propanol, 1-methoxy-2-propanol (PGME); ketones having 3 to 6 carbon atoms such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; esters having 2 to 4 carbon atoms such as ethyl acetate and butyl acetate; saturated or unsaturated hydrocarbons having 1 to 6 carbon atoms; aromatic hydrocarbons such as benzene and toluene; halogenated hydrocarbons such as methylene chloride and chloroform; lower alkyl ethers having 2 to 5 carbon atoms; polar solvents such as N,N-dimethylformamide (DMF), N,N-dimethylacetamide, and dimethyl sulfoxide. These can be used alone or in admixture of two or more. The amount of the medium used may be an effective amount capable of dispersing the modified cellulose fibers, and it is preferably 1 mass times or more, more preferably 2 mass times or more, preferably 500 mass times or less, and more preferably 200 mass times or less based on the modified cellulose fibers.

[0075] As an apparatus used for the micronization treatment, in addition to a high-pressure homogenizer, known dispersers are preferably used. For example, a disintegrator, a beating machine, a low-pressure homogenizer, a grinder, a mascoloider, a cutter mill, a ball mill, a jet mill, a short-axis extruder, a twin-screw extruder, an ultrasonic stirrer, a household juice mixer, etc. can be used. Further, the solid content concentration of the modified cellulose fiber in the micronization treatment is preferably 50% by mass or less.

[0076] 〔Properties of Modified Cellulose Fibers〕 The main properties of the modified cellulose fibers in the present invention are as follows.

[0077] (Crystal Structure) The modified cellulose fibers have a cellulose I-type crystal structure from the viewpoint of enhancing the adhesion strength. Here, the cellulose I-type crystal structure is derived from the raw material cellulose fibers, preferably the raw material natural cellulose fibers. The crystallinity of the modified cellulose fibers is preferably 10% or more, more preferably 15% or more, still more preferably 20% or more from the viewpoint of enhancing the adhesion strength. Further, from the viewpoint of raw material availability, it is preferably 90% or less, more preferably 85% or less, still more preferably 80% or less, still more preferably 75% or less. In the present specification, the crystallinity of the cellulose fibers is the cellulose I-type crystallinity calculated from the diffraction intensity value by the X-ray diffraction method and can be measured according to the method described in the examples below. Note that cellulose I-type refers to the crystal form of natural cellulose, and the cellulose I-type crystallinity means the ratio of the amount of the crystal region in the whole cellulose fiber. The presence or absence of the cellulose I-type crystal structure can be determined by the presence of a peak at 2θ = 22.6° in the X-ray diffraction measurement.

[0078] (Average Fiber Diameter) The modified cellulose fiber is preferably one that has been refined to a nanometer size. Therefore, from the viewpoints of handleability, availability, and cost, the average fiber diameter of the modified cellulose fiber is preferably 1 nm or more, more preferably 2 nm or more, and from the viewpoints of enhancing handleability, dispersibility, and adhesion strength, it is preferably 300 nm or less, more preferably 200 nm or less, still more preferably 150 nm or less, still more preferably 120 nm or less, and even more preferably 20 nm or less. Therefore, as one aspect of the preferable modified cellulose fiber in the present invention, those having a cellulose I crystal structure and an average fiber diameter of 1 nm or more and 300 nm or less can be mentioned.

[0079] (Average fiber length) As the average fiber length of the modified cellulose fiber, from the viewpoint of enhancing adhesion strength, it is preferably 10 nm or more, more preferably 30 nm or more, still more preferably 50 nm or more. On the other hand, from the viewpoints of enhancing spinnability and elongation at break, it is 1000 nm or less, preferably 800 nm or less, more preferably 500 nm or less, still more preferably 300 nm or less, and still more preferably less than 150 nm.

[0080] (Average aspect ratio) As the average aspect ratio of the modified cellulose fiber, from the viewpoint of enhancing adhesion strength, it is preferably 5 or more, more preferably 10 or more, still more preferably 20 or more. On the other hand, from the viewpoints of enhancing spinnability and adhesion strength, it is preferably 300 or less, more preferably 200 or less, still more preferably 150 or less, still more preferably 100 or less, and even more preferably 70 or less. By setting the average fiber length and average aspect ratio within the above ranges, the adhesiveness between materials with different physical properties (for example, materials with different linear expansion coefficients) is also excellent. The average fiber diameter, average fiber length, and average aspect ratio of the modified cellulose fiber are determined by the method described in the examples below.

[0081] (Bonding amount and introduction rate of the modifying group) The amount of the modifying group bonded to the modified cellulose fiber is preferably 0.01 mmol / g or more from the viewpoint of enhancing the adhesive strength, and is preferably 3.0 mmol / g or less from the same viewpoint. When two or more arbitrary modifying groups are simultaneously introduced into the modified cellulose fiber as the modifying group, the amount of the modifying group bonded is preferably within the above range.

[0082] The introduction rate of the modifying group in the modified cellulose fiber is preferably 10 mol% or more from the viewpoint of dispersibility, and the higher the better, and is preferably 100 mol%. When two or more arbitrary modifying groups are simultaneously introduced as the modifying group, it is preferably within the above range as long as the total introduction rate does not exceed 100 mol% of the upper limit.

[0083] The amount of the modifying group bonded and the introduction rate can be adjusted by the type and addition amount of the modifying compound, reaction temperature, reaction time, type of solvent, etc. The amount of the modifying group bonded (mmol / g) and the introduction rate (mol%) refer to the amount and ratio of the modifying group introduced (bonded) to the anionic group in the modified cellulose fiber. The amount of the modifying group bonded and the introduction rate in the modified cellulose fiber are calculated by the method described in the following examples, for example, when the anionic group is a carboxy group.

[0084] [Resin] Examples of the resin in the resin composition of the present invention include epoxy resins other than (B) urethane-modified epoxy resin and (C) urethane-modified epoxy resin, and the resin composition of the present invention may contain the resins of component (B) and component (C).

[0085] The urethane-modified epoxy resin of component (B) may be a resin having a urethane bond and two or more epoxy groups in the molecule. For example, a resin obtained by reacting a compound having a urethane bond obtained by an addition reaction of a polyhydroxy compound having a hydroxy group (such as polyether polyol, polyester polyol, polybutadiene polyol, polyolefin polyol, an adduct of hydroxycarboxylic acid and alkylene oxide, etc.) and a polyisocyanate compound having an isocyanate group (such as tolylene diisocyanate, diphenylmethane diisocyanate, naphthalene diisocyanate, etc.) with a bisphenol type epoxy resin (epoxy compound having a hydroxy group) is used. A urethane-modified epoxy resin may be a commercially available product. Examples of commercially available products include the Adeka Resin EPU series from ADEKA Corporation, the Epoky (registered trademark) series from Mitsui Chemicals, Inc., and the like.

[0086] From the viewpoint of suppressing dripping of the liquid after coating, the preferred viscosity range of the urethane-modified epoxy resin as the component (B) is preferably 1,000 mPa·s / 25 °C or more, more preferably 3,000 mPa·s / 25 °C or more, still more preferably 5,000 mPa·s / 25 °C or more. On the other hand, from the viewpoints of coatability and ejectability, it is preferably 1,000,000 mPa·s / 25 °C or less, more preferably 750,000 mPa·s / 25 °C or less, still more preferably 500,000 mPa·s / 25 °C or less. Also, from the viewpoint of forming a cured product having excellent adhesiveness, the preferred range of the epoxy equivalent of the urethane-modified epoxy resin as the component (B) is preferably 100 g / equivalent or more, more preferably 125 g / equivalent or more, still more preferably 150 g / equivalent or more. On the other hand, from the viewpoint of the development of the mechanical strength of the cured product, it is preferably 500 g / equivalent or less, more preferably 400 g / equivalent or less, still more preferably 350 g / equivalent or less.

[0087] The "epoxy resin other than the urethane-modified epoxy resin" as the component (C) is an epoxy resin that does not correspond to the above component (B) among the epoxy resins in the technical field of the present invention.

[0088] More specifically, at least one selected from the group consisting of bisphenol type epoxy resins, rubber-modified epoxy resins, alicyclic epoxy resins, glycidylamine type epoxy resins, polysulfide-modified epoxy resins, chelate-modified epoxy resins, trisphenol methane type epoxy resins, naphthalene type epoxy resins, dicyclopentadiene-modified epoxy resins, aliphatic epoxy resins such as epoxidized products of aliphatic polyols or their derivatives, polyether-modified epoxy resins, polyfunctional aromatic epoxy resins, and hydrogenated bisphenol type epoxy resins is included in the epoxy resin of component (C). Here, examples of the alicyclic epoxy resin include glycidyl ester type epoxy resins, glycidylamine type epoxy resins, phenol novolac type epoxy resins, alicyclic epoxy resins having an ester skeleton, and the like. Further, examples of the epoxy resin of component (C) also include cyclohexane type epoxy resins, cyclohexanedimethanol type epoxy resins, glycidylamine type epoxy resins, epoxy resins which are epoxidized products of polybutadiene polyols, and the like. Such resins are referred to as "general-purpose epoxy resins" in this specification. Among these, from the viewpoint of improving adhesion strength and tensile strength, aliphatic epoxy resins are preferable, bisphenol type epoxy resins are more preferable, one or more selected from bisphenol A type epoxy resins, bisphenol F type epoxy resins, and bisphenol S type epoxy resins are still more preferable, and bisphenol A type epoxy resin is even more preferable.

[0089] Specific examples of general-purpose epoxy resins include, for example, jER807, jER828, jER828US, jER828EL, jER825, jER630, jER630LSD, etc. manufactured by Mitsubishi Chemical Corporation; Adeka Resin EP-4100, Adeka Resin EP-4300E, Adeka Resin EP-4400, Adeka Resin EP-4901E, Adeka Resin EP-4000, Adeka Resin EP-4000S, Adeka Resin EP-4005, Adeka Resin EPR-1415-1, Adeka Resin EPR-2000, Adeka Resin EPR-2007, Adeka Resin EP-49-10N, Adeka Resin EP-49-10P2, Adeka Resin EP-49-23, etc. manufactured by ADEKA Corporation; FLEP-50, FLEP-60, etc. manufactured by Toray Fine Chemical Co., Ltd.; Epolite 40E, Epolite 100E, Epolite 200E, Epolite 400E, Epolite 70P, Epolite 200P, Epolite 400P, Epolite 1500NP, Epolite 1600, Epolite 80MF, Epolite 4000, Epolite 3002(N), etc. manufactured by Kyoeisha Chemical Co., Ltd.; Denacol EX-201, Denacol EX-201-IM, Denacol EX-252, Denacol EX-991L, etc. manufactured by Nagase ChemteX Corporation. These may be used alone or in combination of two or more.

[0090] From the viewpoint of suppressing dripping of the liquid after coating, the preferred viscosity range of the general-purpose epoxy resin is preferably 1,000 mPa·s / 25 °C or more, more preferably 3,000 mPa·s / 25 °C or more, still more preferably 5,000 mPa·s / 25 °C or more. On the other hand, from the viewpoints of coatability and dischargeability, it is preferably 1,000,000 mPa·s / 25 °C or less, more preferably 750,000 mPa·s / 25 °C or less, still more preferably 500,000 mPa·s / 25 °C or less.

[0091] Furthermore, an epoxy-based diluent having an epoxy group, which is known as a reactive diluent, can also be treated as the epoxy resin of component (C). Since such a reactive diluent has a lower viscosity than the above-mentioned component (C), the viscosity of the resin composition can be lowered by blending an appropriate amount of the reactive diluent. Specific examples of such reactive diluents include monofunctional n-butanol glycidyl ether, butyl glycidyl ether, butyl phenyl glycidyl ether, hexyl glycidyl ether, 2-ethylhexyl glycidyl ether, allyl glycidyl ether, tetrahydrofurfuryl glycidyl ether, furfuryl glycidyl ether, trimethoxysilyl glycidyl ether, other higher alcohol-based glycidyl ethers, glycidyl methacrylate, etc., and polyfunctional 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, trimethylolpropane triglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol glycidyl ether, dimer acid diglycidyl ester, etc. The preferred viscosity range of these reactive diluents is preferably 15 mPa·s / 25°C or more, more preferably 20 mPa·s / 25°C or more, still more preferably 30 mPa·s / 25°C or more, from the viewpoint of forming a cured product having excellent adhesiveness. On the other hand, from the viewpoint of handleability, it is preferably 3,000 mPa·s / 25°C or less, more preferably 2,000 mPa·s / 25°C or less, still more preferably 1,000 mPa·s / 25°C or less. Reactive diluents are commercially available. For example, Adeka Glycilol ED-503, Adeka Glycilol ED-503G, Adeka Glycilol ED-506, Adeka Glycilol ED-523T, Adeka Glycilol ED-505, etc. manufactured by ADEKA Corporation can be mentioned.

[0092] (C) As a component, a general-purpose epoxy resin and a reactive diluent may be used in combination. When used in combination, the ratio of the two, from the viewpoints of coatability and dischargeability, the reactive diluent is preferably 1 part by mass or more, more preferably 3 parts by mass or more, still more preferably 5 parts by mass or more, based on 100 parts by mass of the general-purpose epoxy resin. On the other hand, from the viewpoints of suppressing dripping of the liquid after coating and forming a cured product having excellent adhesiveness, the reactive diluent is preferably 50 parts by mass or less, more preferably 40 parts by mass or less, still more preferably 30 parts by mass or less.

[0093] For adjusting the viscosity of the composition of the present invention and improving the mechanical properties after curing, etc., fillers known in the field of the present invention can also be compounded. Such fillers include (A) fillers other than modified cellulose fibers, such as calcium carbonate, talc, magnesia, calcium silicate, calcium hydroxide, aluminum hydroxide, magnesium hydroxide, alumina, zircon, graphite, barium sulfate, mica, kaolin, wollastonite, clay, mica, feldspar, diorite, chlorite, bentonite, montmorillonite, barite, cristobalite, dolomite, quartz, diatomaceous earth, aluminum silicate, barium carbonate, magnesium carbonate, zinc carbonate, mineral fibers, textile fibers, glass fibers, aramid pulp, boron fibers, carbon fibers, phosphates, crystalline silica, amorphous silica, fused silica, fumed silica, calcined silica, precipitated silica, pulverized fine powder silica, etc. silica, silica sand, rosin stone, cement, resin powders such as polyethylene, calcium oxide, iron oxide, zinc oxide, titanium oxide, barium oxide, magnesium oxide, titanium dioxide, hollow inorganic beads such as hollow ceramic beads and hollow glass beads, hollow organic beads made of polyester resin, etc., glass beads, metal powders, asphalt substances, etc. can be exemplified. These may be used alone or in combination of two or more.

[0094] In addition, if necessary, various additives, for example, curing agents and curing accelerators, reaction retardants, anti-aging agents, antioxidants, pigments, dyes, plasticizers, silane coupling agents, adhesion imparting agents, flame retardants, antistatic agents, ultraviolet absorbers, surfactants, dispersants, dehydrating agents, thermosetting resins other than epoxy resins, thermoplastic resins, etc. can be appropriately combined and used.

[0095] The above-mentioned curing agent or curing accelerator can be widely used for curing epoxy resins. Examples of the curing agent include dicyandiamide, acid anhydrides, phenolic resin curing agents, polyamine compounds, polymercaptan compounds, isocyanate compounds, organic acids, etc. In the present invention, from the viewpoint of storage stability, one or more selected from dicyandiamide, acid anhydrides, polyamine compounds, and polymercaptan compounds are preferred.

[0096] Dicyandiamide is represented by H2N-C(NH2)=N-CN, and its melting point is usually 205 to 215 °C, and for those with high purity, it is 207 to 212 °C.

[0097] As the acid anhydride, an acid anhydride of an unsaturated dicarboxylic acid having a radically polymerizable unsaturated bond is preferable, one or more selected from aromatic acid anhydrides, cycloaliphatic acid anhydrides, and aliphatic acid anhydrides are more preferable, and an acid anhydride that is liquid at 25 °C is even more preferable.

[0098] Specific examples of the acid anhydride include acid anhydrides such as fumaric acid, maleic acid, succinic acid, dodecenyl succinic acid, tetrahydrophthalic acid, methyltetrahydrophthalic acid, hexahydrophthalic acid, methylhexahydrophthalic acid, itaconic acid, and citraconic acid. Preferably, they are acid anhydrides of maleic acid, tetrahydrophthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, and methylhexahydrophthalic acid. More preferably, they are one or more selected from tetrahydrophthalic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, and methylhexahydrophthalic anhydride. Examples of the organic phosphorus compound include triphenylphosphine, etc. Examples of the quaternary ammonium salt include tetraethylammonium bromide, tetrabutylammonium bromide, etc.

[0099] Examples of the quaternary phosphonium salt include tetrabutylphosphonium decanoate, tetrabutylphosphonium laurate, tetrabutylphosphonium myristate, tetrabutylphosphonium palmitate, and salts of tetrabutylphosphonium cation with anions such as bicyclo[2.2.1]heptane-2,3-dicarboxylic acid, methylbicyclo[2.2.1]heptane-2,3-dicarboxylic acid, 1,2,4,5-cyclohexanetetracarboxylic acid, methanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, 4-chlorobenzenesulfonic acid, dodecylbenzenesulfonic acid, etc.

[0100] Examples of the organometallic salts include tin octylate, zinc octylate, dibutyltin dilaurate, aluminum acetylacetone complex, etc., and examples of the boron compounds include boron trifluoride, triphenyl borate, etc. These acid anhydrides can be used alone or in admixture of two or more.

[0101] Examples of the polyamine compounds include diamine compounds, triamine compounds, etc., and one or more selected from aliphatic diamines, aromatic diamines, and dicycloaliphatic amines are preferred.

[0102] Examples of the polymercaptan compounds include polyhydric alcohol esters of mercaptocarboxylic acids, esters of monomercaptan monohydric alcohols containing polycarboxylic acids, compounds having mercapto groups at the terminals of polypropylene glycol or polyethylene glycol chains, other ester-containing polymercaptans described in U.S. Patent No. 4,126,505, propoxylated ether polythiols described in U.S. Patent No. 4,092,293, polymercaptan-containing resins having a molecular weight of 750 to 7000 described in U.S. Patent No. 3,258,495, dimercaptopolysulfide polymers described in U.S. Patent No. 2,919,255, thiolated oligomer triglycerides, etc. Among these, polyhydric alcohol esters of mercaptocarboxylic acids are preferred.

[0103] Examples of the polyhydric alcohol esters of mercaptocarboxylic acids preferably include trimethylolpropane trimercaptopropionate, trimethylolpropane trithiogluconate, pentaerythritol tetramercaptopropionate, pentaerythritol tetrathiogluconate, trimethylolethane trimercaptopropionate, etc.

[0104] As the curing accelerator, it can be appropriately selected according to the type of curing agent. Examples of the curing accelerator for dicyandiamide include ureas, imidazoles, Lewis acid catalysts, etc. Among these, it is preferable to use ureas. Examples of ureas include 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU), toluene bis(dimethylurea), 4,4'-methylenebis(phenyldimethylurea), 3-phenyl-1,1-dimethylurea, dichlorodimethylurea, phenyldimethylurea, etc.

[0105] As the curing accelerator for acid anhydrides, tertiary amines, tertiary amine salts, imidazoles, organophosphorus compounds, quaternary ammonium salts, quaternary phosphonium salts, organometallic salts, boron compounds, etc. can be used.

[0106] Resin Composition of the Present Invention In terms of enhancing the adhesive strength, the amount of resin in the composition of the present invention, in terms of the blending amount, is preferably 10% by mass or more, preferably 97% by mass or less. When not containing a filler, in terms of enhancing the adhesive strength, the amount of resin, in terms of the blending amount, is more preferably 50% by mass or more, still more preferably 60% by mass or more, even more preferably 70% by mass or more. On the other hand, from the perspective of cost, it is more preferably 95% by mass or less, still more preferably 92% by mass or less. When containing a filler, in terms of enhancing the adhesive strength, the amount of resin, in terms of the blending amount, is more preferably 10% by mass or more, still more preferably 20% by mass or more, even more preferably 30% by mass or more. On the other hand, from the perspective of cost, it is more preferably 95% by mass or less, still more preferably 80% by mass or less, even more preferably 70% by mass or less.

[0107] As the combination of the content of component (B) and the content of component (C) in the composition of the present invention, from the perspective of achieving both adhesive strength and tensile strength, preferably, the content of component (B) is 1% by mass or more and less than 80% by mass, and the content of component (C) is 1% by mass or more and less than 90% by mass. When not containing a filler, from the above viewpoints, more preferably, the content of component (B) is 5% by mass or more and 65% by mass or less, and the content of component (C) is 35% by mass or more and less than 85% by mass. Even more preferably, the content of component (B) is 10% by mass or more and 60% by mass or less, and the content of component (C) is 40% by mass or more and 80% by mass or less.

[0108] When containing a filler, from the above viewpoints, more preferably, the content of component (B) is 3% by mass or more and 55% by mass or less, and the content of component (C) is 15% by mass or more and less than 55% by mass. Even more preferably, the content of component (B) is 5% by mass or more and 45% by mass or less, and the content of component (C) is 20% by mass or more and 50% by mass or less.

[0109] As the content ratio [(C) / (B)] of component (C) to component (B) in the composition of the present invention, from the viewpoint of achieving both adhesion strength and tensile strength, it is preferably 0.4 or more and 15 or less, more preferably 0.5 or more and 12 or less, and even more preferably 0.6 or more and 10 or less.

[0110] As the mass ratio of cellulose fiber / component (B) in the composition of the present invention, in terms of the blending amount, from the viewpoint of increasing the elongation at break, it is preferably 0.001 or more, more preferably 0.005 or more, and even more preferably 0.01 or more. On the other hand, from the viewpoint of viscosity, it is preferably 10 or less, more preferably 5 or less, even more preferably 3 or less, even more preferably 1.0 or less, even more preferably 0.5 or less, and even more preferably 0.10 or less.

[0111] As the mass ratio of cellulose fiber / resin in the composition of the present invention, in terms of the blending amount, from the viewpoint of increasing the adhesion strength, it is preferably 0.01 / 100 or more, more preferably 0.05 / 100 or more, even more preferably 0.1 / 100 or more, even more preferably 0.3 / 100 or more, and even more preferably 0.5 / 100 or more. On the other hand, from the viewpoint of viscosity, it is preferably 30 / 100 or less, more preferably 20 / 100 or less, even more preferably 15 / 100 or less, even more preferably 10 / 100 or less, even more preferably 7 / 100 or less, and even more preferably 5 / 100 or less. Note that the mass of the cellulose fiber referred to here is the mass of the part obtained by removing the modifying group from the modified cellulose fiber, that is, the mass of the cellulose fiber part.

[0112] When the composition of the present invention contains a curing agent and / or a curing accelerator, the preferable amount of the curing agent cannot be generally stated because it is adjusted according to the use environment (heating temperature, heating time) of the adhesive and the influence of other compositions. However, the amounts of these components, as the total amount of both, in terms of the compounding amount, are preferably 0.5 parts by mass or more, more preferably 1 part by mass or more, with respect to 100 parts by mass of the resin, while preferably 80 parts by mass or less, more preferably 70 parts by mass or less.

[0113] When the composition of the present invention contains a filler, in terms of the compounding amount, from the viewpoint of cost, it is preferably 5 parts by mass or more, more preferably 15 parts by mass or more, still more preferably 30 parts by mass or more, with respect to 100 parts by mass of the resin, while from the viewpoint of strength, it is preferably 90 parts by mass or less, more preferably 80 parts by mass or less, still more preferably 70 parts by mass or less.

[0114] Regarding the viscosity of the composition of the present invention, from the viewpoint of suppressing dripping of the liquid after coating, it is preferably 1,000 mPa·s / 25°C or more, more preferably 3,000 mPa·s / 25°C or more, still more preferably 5,000 mPa·s / 25°C or more, while from the viewpoints of coatability and dischargeability, it is preferably 1,000,000 mPa·s / 25°C or less, more preferably 750,000 mPa·s / 25°C or less, still more preferably 500,000 mPa·s / 25°C or less. Here, the above viscosity is measured under the measurement conditions of a shear rate of 1 s based on JIS-K2220. -1 It is measured under the measurement conditions of a shear rate of 1 s based on JIS-K2220.

[0115] The resin composition of the present invention may further contain a solvent, and the viscosity of the resin composition can be adjusted to a desired degree using the solvent. Examples of the solvents that can be used include, for example, dimethylformamide, ethyl acetate, methyl methacrylate, ethanol, isopropanol, N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), N,N-dimethylacetamide, tetrahydrofuran (THF), diester of succinic acid and triethylene glycol monomethyl ether, acetone, methyl ethyl ketone (MEK), acetonitrile, dichloromethane, chloroform, toluene, 1-methoxy-2-propanol (PGME), acetic acid, etc. One of these can be used alone or two or more of them can be used in combination. When using a solvent, the amount thereof is, for example, preferably 50 parts by mass or more, more preferably 100 parts by mass or more, relative to 100 parts by mass of the resin, while preferably 5000 parts by mass or less, more preferably 2000 parts by mass or less.

[0116] 〔Manufacturing method of resin composition〕 The resin composition of the present invention can be produced, for example, by mixing the modified cellulose fiber and the resin, etc. Further, if necessary, a solvent, a curing agent, and other components can be mixed. When optionally blending a filler, after the step of mixing the modified cellulose fiber and the resin, etc., it can further have step α. Step α: Step of adding and mixing a filler

[0117] When making it a one-component adhesive, after the step of mixing the modified cellulose fiber and the resin, etc., or when optionally blending a filler, after step α, it can further have the following step A and step B. Step A: Step of adding and mixing a curing agent and / or a curing accelerator Step B: Step of adding and mixing a reactive diluent

[0118] The method of mixing each component constituting the adhesive is not particularly limited, and examples thereof include general methods, for example, a method using a stirrer such as a planetary mixer. In the final step of manufacturing the resin composition, defoaming treatment can be optionally performed.

[0119] One of the preferred embodiments of the method for manufacturing the adhesive of the present invention is In a method for manufacturing a resin composition containing (B) a urethane-modified epoxy resin and (C) an epoxy resin other than the urethane-modified epoxy resin, Step 1: A step of mixing (A) modified cellulose fiber and (B) a urethane-modified epoxy resin, and Step 2: A step of mixing the mixture obtained in Step 1 with (C) an epoxy resin other than the urethane-modified epoxy resin It is a manufacturing method having.

[0120] According to such a manufacturing method, the resin composition of the present invention obtained by mixing a mixture of (A) modified cellulose fiber and (B) a urethane-modified epoxy resin and (C) an epoxy resin other than the urethane-modified epoxy resin can be obtained. When a plurality of types of the resin of component (C) are used, the resin of the first component (C) may be mixed with the mixture of components (A) and (B), and then the resin of the second component (C) may be mixed.

[0121] In such a manufacturing method, at the time of mixing in Step 1, from the viewpoint of further improving the dispersibility, it is preferable to perform a dispersion treatment. Examples of the dispersion treatment include a dispersion treatment using a grinding machine such as a mas colloidizer or a dispersion treatment using a high-pressure homogenizer in a medium. From the viewpoint of dispersion uniformity, a dispersion treatment using a high-pressure homogenizer is preferable. The medium shall conform to the description of the above medium. When a medium is used, in order to improve the mixability in Step 2, it is preferable to distill off the solvent with an evaporator. In such a manufacturing method, from the viewpoint of increasing the elongation at break in terms of the compounding amount, the mass ratio of the modified cellulose fiber / component (B) in Step 1 is preferably 0.005 or more, more preferably 0.010 or more, still more preferably 0.030 or more. On the other hand, from the viewpoint of viscosity, it is preferably 10 or less, more preferably 5 or less, still more preferably 3 or less, still more preferably 1.0 or less, still more preferably 0.5 or less, still more preferably 0.10 or less, still more preferably 0.07 or less.

[0122] Another preferred embodiment of the method for producing the resin composition of the present invention is In a method for producing a resin composition containing (B) a urethane-modified epoxy resin and (C) an epoxy resin other than the urethane-modified epoxy resin, it is a production method having the following Step 3 or Step 4. Step 3: A step of mixing (A) a modified cellulose fiber, (B) a urethane-modified epoxy resin, and (C) an epoxy resin other than the urethane-modified epoxy resin Step 4: A step of mixing (B) a urethane-modified epoxy resin and (C) an epoxy resin other than the urethane-modified epoxy resin (Step 4-1), and mixing the obtained composition with (A) a modified cellulose fiber (Step 4-2).

[0123] According to such a production method, the resin composition of the present invention obtained by mixing a mixture of (B) a urethane-modified epoxy resin and (C) an epoxy resin other than the urethane-modified epoxy resin with (A) a modified cellulose fiber can be obtained.

[0124] In such a manufacturing method, from the viewpoint of further improving the dispersibility during mixing in Step 3 or Step 4-2, it is preferable to perform a dispersion treatment. Examples of the dispersion treatment include a dispersion treatment using a grinding machine such as a mascoloider or a dispersion treatment using a high-pressure homogenizer in a medium. From the viewpoint of dispersion uniformity, a dispersion treatment using a high-pressure homogenizer is preferable. The medium conforms to the above description of the medium. In addition, when using a medium, in order to improve the mixability in the next step, it is preferable to distill off the solvent with an evaporator.

[0125] In such a production method, from the viewpoint of increasing the elongation at break, the mass ratio of the modified cellulose fiber to the total of (component (B) and component (C)) in step 3 or step 4-2 is preferably 0.005 or more, more preferably 0.010 or more, still more preferably 0.030 or more, when converted to the blending amount. On the other hand, from the viewpoint of viscosity, it is preferably 10 or less, more preferably 5 or less, still more preferably 3 or less, still more preferably 1.0 or less, still more preferably 0.5 or less, still more preferably 0.10 or less, still more preferably 0.07 or less.

[0126] One of another preferred embodiments of the method for producing the resin composition of the present invention is In the method for producing a resin composition containing (B) a urethane-modified epoxy resin and (C) an epoxy resin other than the urethane-modified epoxy resin, Step 5: A step of mixing (A) a modified cellulose fiber and (C) an epoxy resin other than the urethane-modified epoxy resin Step 6: A step of mixing the composition obtained in step 5 with (B) a urethane-modified epoxy resin It is a production method having

[0127] According to such a production method, the resin composition of the present invention obtained by mixing a mixture of (A) a modified cellulose fiber and (C) an epoxy resin other than the urethane-modified epoxy resin with (B) a urethane-modified epoxy resin can be obtained.

[0128] In such a production method, from the viewpoint of further improving the dispersibility during mixing in step 5, it is preferable to perform a dispersion treatment. Examples of the dispersion treatment include a dispersion treatment using a grinding machine such as a mas colloid mill or a dispersion treatment using a high-pressure homogenizer in a medium. From the viewpoint of dispersion uniformity, a dispersion treatment using a high-pressure homogenizer is preferable. The medium is as described in the above description of the medium. In addition, when using a medium, in order to improve the miscibility in step 6, it is preferable to distill off the solvent with an evaporator.

[0129] In such a manufacturing method, from the viewpoint of increasing the elongation at break in terms of the compounding amount, the mass ratio of the modified cellulose fiber / component (C) in step 5 is preferably 0.005 or more, more preferably 0.010 or more, still more preferably 0.030 or more. On the other hand, from the viewpoint of viscosity, it is preferably 10 or less, more preferably 5 or less, still more preferably 3 or less, still more preferably 1.0 or less, still more preferably 0.5 or less, still more preferably 0.10 or less, and still more preferably 0.07 or less.

[0130] Among the preferred embodiments of these manufacturing methods, from the viewpoints of handleability and improvement of elongation in tensile tests and shear adhesion tests, a manufacturing method having steps 1 and 2, or a manufacturing method having step 3 or step 4 is more preferable, and a manufacturing method having steps 1 and 2 is even more preferable.

[0131] Here, the preferable compounding ratios of component (A), component (B), and component (C) in the above manufacturing method can be obtained from the above "amount of resin in the composition of the present invention" and "mass ratio of modified cellulose fiber / resin in the composition of the present invention".

[0132] Examples of the solvent that can be used during manufacturing include the solvents that can be used in the above resin composition of the present invention. When using a solvent, the amount is, for example, preferably 50 parts by mass or more, more preferably 100 parts by mass or more, with respect to 100 parts by mass of the resin. On the other hand, it is preferably 5000 parts by mass or less, more preferably 2000 parts by mass or less.

[0133] <Adhesive and Adhesion Method> The adhesive of the present invention contains the above resin composition of the present invention or consists of the above resin composition of the present invention.

[0134] Examples of the adhesion method of the present invention include, for example, a method of applying the adhesive of the present invention onto a structure (or its member) and bonding it to the counterpart structure (or its member). Such an adhesive includes a structural adhesive.

[0135] A preferred embodiment of the adhesive of the present invention is a structural adhesive. A structural adhesive is an adhesive used in structures where mechanical strength is required, such as in vehicles and buildings, and is preferably used to bond vehicle assembly parts. It is an adhesive that replaces or reinforces conventional joining techniques such as welding, nuts and bolts, and rivets. Therefore, a method for bonding vehicle assembly parts is provided, which includes a step of bonding vehicle assembly parts using the adhesive of the present invention. The adhesive of the present invention can be used as a structural adhesive itself, or can also be used as a material for an adhesive to further blend other components to obtain an adhesive.

[0136] Examples of vehicles include rockets, airplanes, drones, automobiles, ships, etc. Specifically, it is used to manufacture an automobile structure by structurally bonding parts such as an automobile body and automobile parts. In particular, it is preferably used for bonding in a method (weld bond method) that combines spot welding and an adhesive.

[0137] The method for applying the adhesive to the structure is not particularly limited. For example, methods using a spray, a sealant gun, a dispenser, a nozzle, a brush, a spatula, etc. can be mentioned. Among these, since the adhesive of the present invention has excellent dischargeability, it is preferable to use a dispenser. When using a dispenser, an embodiment in which the adhesive is discharged from the dispenser and applied to the structure can be mentioned.

[0138] After bonding the structure and the mating structure together, for example, by maintaining at -30 to 200 °C for 1 minute to 3 days, the bonding between the two can be completed.

[0139] The adhesive of the present invention has excellent bonding properties with various materials, such as metals like iron, aluminum, and copper, alloys like steel and aluminum alloys, plastics like polypropylene, polyamide, and polyacetal, carbon fiber reinforced plastics and glass fiber reinforced plastics, rubber, carbon fiber, glass, ceramics, etc. It has high strength and can contribute to the weight reduction of structures, such as vehicles, and the reduction of welding costs. The adhesive of the present invention is preferably used for bonding metal members, and more preferably used when the bonding surface of the metal member contains aluminum.

[0140] In the bonding method of the present invention, it is preferable that the surface to which the adhesive is applied on the structure or its member, that is, the bonding surface, is made of a material including one or more selected from the group consisting of such metals, plastics, ceramics, and glass. A material including metal and / or plastic is more preferable, and a material including metal is even more preferable. That is, in the bonding method of the present invention, it is preferable to apply the adhesive of the present invention on a metal member and bond it to the other metal member. Note that a metal member is a material formed into a shape by metal, different from powders and the like.

[0141] As the material of the bonding surface used in the bonding method of the present invention, it is preferable to include a metal with a linear expansion coefficient of 20×10 -6 / °C or more. Examples of such metals include aluminum and zinc. Even if the linear expansion coefficient is high, it is presumed that the adhesive of the present invention has high bonding strength because thermal shrinkage is suppressed.

[0142] More specifically, examples of the adhesion surface of the metal member include steel plates, SPC steel plates, plated steel plates (e.g., electro-galvanized steel plates, hot-dip galvanized steel plates, organic surface-treated steel plates, alloyed galvanized steel plates, zinc-nickel alloy plated steel plates, tin-lead plated steel plates, cationic electrodeposited coating steel plates), aluminum plates, aluminum alloy plates (e.g., aluminum-manganese alloy plates, aluminum-magnesium alloy plates), and magnesium plates. Examples of the adhesion surface of plastics include fiber-reinforced plastic fiber plates such as carbon fiber-reinforced plastics and glass fiber-reinforced plastics. Examples of the adhesion surface of ceramics include barium titanate, boron nitride, silicon nitride, lead zirconate titanate, aluminum oxide, aluminum nitride, silicon carbide, zinc oxide, zirconia, ferrite, indium oxide, and silicon. Examples of the adhesion surface of glass include soda-lime glass, lead glass, borosilicate glass, and quartz glass. In particular, when the adhesion surface of the metal member contains aluminum, the adhesive composition and the adhesion method of the present invention are preferably applied.

[0143] The adhesive of the present invention is particularly excellent in the adhesiveness between materials having different physical properties (e.g., metal materials having different linear expansion coefficients). For example, it is for the adhesion between a metal having a linear expansion coefficient of 20×10 -6 / °C or more and a metal having a linear expansion coefficient of less than 20×10 -6 / °C. Specifically, it is also excellent in the adhesion strength of a combination of dissimilar metals (e.g., steel and aluminum alloy, i.e., a metal containing iron and a metal containing aluminum). The metal containing iron can be used as a steel plate, and the metal containing aluminum can be used as an alloy plate. Therefore, the adhesion method described in this specification can also be preferably applied to a method for adhering dissimilar metals.

[0144] <Method for Improving the Elongation at Break of Structural Adhesives> By mixing the above-mentioned (A) modified cellulose fiber and the above-mentioned (B) urethane-modified epoxy resin, the elongation at break of the adhesive can be improved. Therefore, the method for improving the elongation at break of the structural adhesive of the present invention includes a step of mixing (A) modified cellulose fiber and (B) urethane-modified epoxy resin.

[0145] <Adhesive Kit> The adhesive kit of the present invention comprises a container containing the above-mentioned adhesive of the present invention. The adhesive kit of the present invention is provided as a one-component adhesive or a two-component adhesive. In the case of a one-component adhesive, the adhesive of the present invention is contained in one container, and a curing agent and a curing accelerator are also contained in the same container. In the case of a two-component adhesive, an adhesive kit comprising a first container containing the resin composition of the present invention and a second container containing a curing agent can be exemplified. Such an adhesive kit may further contain a curing accelerator. In the case of a two-component adhesive, since such a kit can cure the adhesive by mixing the adhesive and the curing agent etc. at the time of use, it is highly convenient.

[0146] The container for containing the adhesive, the composition, or each component constituting these is not particularly limited, and conventionally known ones such as tubes, caulking guns, glue guns, and cartridges for dispensers can be used.

[0147] Regarding the above-described embodiments, the present invention further discloses the following resin composition, adhesive, method for adhering vehicle assembled parts, method for manufacturing a resin composition, method for improving the elongation at break of a structural adhesive, and adhesive kit.

[0148] <1> A resin composition containing (A) modified cellulose fiber, (B) urethane-modified epoxy resin, and (C) an epoxy resin other than the urethane-modified epoxy resin.

[0149] <2> The resin composition according to <1>, wherein the modified cellulose fiber has a cellulose I-type crystal structure and an average fiber diameter thereof is preferably 1 nm or more, and preferably 300 nm or less. <3> The resin composition according to <1> or <2>, wherein the average fiber length of the modified cellulose fiber is preferably 10 nm or more, more preferably 30 nm or more, still more preferably 50 nm or more, and preferably 1000 nm or less, more preferably 800 nm or less, still more preferably 500 nm or less, still more preferably 300 nm or less, and still more preferably less than 150 nm. <4> The resin composition according to any one of <1> to <3>, wherein the average aspect ratio of the modified cellulose fiber is preferably 5 or more, more preferably 10 or more, still more preferably 20 or more, and preferably 300 or less, more preferably 200 or less, still more preferably 150 or less, still more preferably 100 or less, and even more preferably 70 or less. <5> The resin composition according to any one of <1> to <4>, wherein the modified cellulose fiber is one in which a modifying group and an anionic modified cellulose fiber are bonded, and the modifying group contains at least one selected from the group consisting of (i) a hydrocarbon group having 3 or more carbon atoms, (ii) a silicone chain, and (iii) an alkylene oxide chain. <6> The resin composition according to any one of <1> to <5>, wherein the modifying group and the anionic group of the anionic modified cellulose fiber are bonded via an ionic bond and / or a covalent bond. <7> The resin composition according to any one of <1> to <6>, wherein the modifying group is bonded to a part or all of the hydroxy groups of the cellulose fiber, or to the carboxy group obtained by converting the group (-CH2OH) at the C6 position of the glucose unit constituting the cellulose fiber into a carboxy group. <8> The resin composition according to any one of <1> to <7>, wherein the number of carbon atoms of the hydrocarbon group is preferably 3 or more, more preferably 8 or more, still more preferably 10 or more, and preferably 30 or less, more preferably 22 or less, still more preferably 18 or less. <9> The resin composition according to any one of <1> to <8> above, wherein the formula weight (molecular weight) of the alkylene oxide chain is preferably 500 or more, more preferably 1,000 or more, and preferably 10,000 or less, more preferably 7,000 or less. <10> The resin composition according to any one of <1> to <9> above, wherein the epoxy resin other than the urethane-modified epoxy resin is at least one selected from the group consisting of bisphenol-type epoxy resins, rubber-modified epoxy resins, alicyclic epoxy resins, glycidylamine-type epoxy resins, polysulfide-modified epoxy resins, chelate-modified epoxy resins, trisphenolmethane-type epoxy resins, naphthalene-type epoxy resins, dicyclopentadiene-modified epoxy resins, aliphatic epoxy resins such as epoxidized products of aliphatic polyols or their derivatives, polyether-modified epoxy resins, polyfunctional aromatic epoxy resins, and hydrogenated bisphenol-type epoxy resins. <11> The resin composition according to any one of <1> to <10> above, wherein the content of component (B) in the composition is preferably 1% by mass or more and less than 80% by mass, and the content of component (C) is preferably 1% by mass or more and less than 80% by mass. <12> The resin composition according to any one of <1> to <11> above, wherein the content of component (B) in the composition is more preferably 5% by mass or more and 65% by mass or less, the content of component (C) is more preferably 35% by mass or more and less than 85% by mass, and still more preferably, the content of component (B) is 10% by mass or more and 60% by mass or less, and the content of component (C) is 40% by mass or more and 80% by mass or less. <13> The resin composition according to any one of <1> to <12> above, wherein the composition is obtained by mixing modified cellulose fibers, a mixture with a urethane-modified epoxy resin, and an epoxy resin other than the urethane-modified epoxy resin. <14> The resin composition according to any one of <1> to <12> above, wherein the composition is obtained by mixing a mixture of a urethane-modified epoxy resin and an epoxy resin other than the urethane-modified epoxy resin with modified cellulose fibers. <15> A resin composition according to any one of <1> to <12>, which is obtained by mixing a mixture of a modified cellulose fiber and an epoxy resin other than a urethane-modified epoxy resin with a urethane-modified epoxy resin. <16> The resin composition according to any one of <1> to <15>, wherein the content ratio [(C) / (B)] of the component (C) to the component (B) in the composition is preferably 0.4 or more and 15 or less, more preferably 0.5 or more and 12 or less, still more preferably 0.6 or more and 10 or less. <17> The resin composition according to any one of <1> to <16>, wherein the mass ratio of cellulose fiber / component (B) in the composition is preferably 0.001 or more, more preferably 0.005 or more, still more preferably 0.01 or more, and preferably 10 or less, more preferably 5 or less, still more preferably 3 or less, still more preferably 1.0 or less, still more preferably 0.5 or less, still more preferably 0.10 or less. <18> The resin composition according to any one of <1> to <17>, wherein the mass ratio of cellulose fiber / resin in the composition, in terms of the blending amount, is preferably 0.01 / 100 or more, more preferably 0.05 / 100 or more, still more preferably 0.1 / 100 or more, still more preferably 0.3 / 100 or more, still more preferably 0.5 / 100 or more, and preferably 30 / 100 or less, more preferably 20 / 100 or less, still more preferably 15 / 100 or less, still more preferably 10 / 100 or less, still more preferably 7 / 100 or less, still more preferably 5 / 100 or less. <19> When the composition contains a filler, in terms of the blending amount, the resin composition according to any one of <1> to <18> is preferably 5 parts by mass or more, more preferably 15 parts by mass or more, still more preferably 30 parts by mass or more, and preferably 90 parts by mass or less, more preferably 80 parts by mass or less, still more preferably 70 parts by mass or less, per 100 parts by mass of the resin. <20> The viscosity of the composition is preferably 1,000 mPa·s / 25 °C or more, more preferably 3,000 mPa·s / 25 °C or more, still more preferably 5,000 mPa·s / 25 °C or more, and is preferably 1,000,000 mPa·s / 25 °C or less, more preferably 750,000 mPa·s / 25 °C or less, still more preferably 500,000 mPa·s / 25 °C or less, the resin composition according to any one of <1> to <19> above. <21> An adhesive containing the composition according to any one of <1> to <20> above. <22> The adhesive according to <21> above, wherein the adhesive is a structural adhesive. <23> The adhesive according to <21> or <22> above, further containing a filler other than the modified cellulose fiber. <24> The adhesive according to any one of <21> to <23> above, which is used for adhering vehicle assembly parts. <25> A method for adhering vehicle assembly parts, comprising a step of adhering vehicle assembly parts using the adhesive according to any one of <21> to <24> above. <26> In a method for producing a resin composition containing a urethane-modified epoxy resin and an epoxy resin other than the urethane-modified epoxy resin, Step 1: A step of mixing a modified cellulose fiber and a urethane-modified epoxy resin, and Step 2: A step of mixing the mixture obtained in Step 1 and an epoxy resin other than the urethane-modified epoxy resin A method for producing a resin composition, comprising: <27> The mass ratio of the modified cellulose fiber / component (B) in Step 1, in terms of the blending amount, is preferably 0.005 or more, more preferably 0.010 or more, still more preferably 0.030 or more, and is preferably 10 or less, more preferably 5 or less, still more preferably 3 or less, still more preferably 1.0 or less, still more preferably 0.5 or less, still more preferably 0.10 or less, still more preferably 0.07 or less, the production method according to <26> above. <28> In a method for producing a resin composition containing a urethane-modified epoxy resin and an epoxy resin other than the urethane-modified epoxy resin, a production method having the following step 3 or step 4. Step 3: A step of mixing a modified cellulose fiber, a urethane-modified epoxy resin, and an epoxy resin other than the urethane-modified epoxy resin Step 4: A step of mixing the urethane-modified epoxy resin and an epoxy resin other than the urethane-modified epoxy resin (step 4-1), and mixing the resulting composition with the modified cellulose fiber (step 4-2). <29> In the production method described in <28> above, the mass ratio of the modified cellulose fiber / (total of component (B) and component (C)) in step 3 or step 4-2 is preferably 0.005 or more, more preferably 0.010 or more, still more preferably 0.030 or more, when converted by the blending amount, and is preferably 10 or less, more preferably 5 or less, still more preferably 3 or less, still more preferably 1.0 or less, still more preferably 0.5 or less, still more preferably 0.10 or less, still more preferably 0.07 or less. <30> In a method for producing a resin composition containing a urethane-modified epoxy resin and an epoxy resin other than the urethane-modified epoxy resin, Step 5: A step of mixing a modified cellulose fiber and an epoxy resin other than the urethane-modified epoxy resin Step 6: A step of mixing the composition obtained in step 5 with the urethane-modified epoxy resin A method for producing a resin composition having the above steps. <31> In the production method described in <30> above, the mass ratio of the modified cellulose fiber / component (C) in step 5 is preferably 0.005 or more, more preferably 0.010 or more, still more preferably 0.030 or more, when converted by the blending amount, and is preferably 10 or less, more preferably 5 or less, still more preferably 3 or less, still more preferably 1.0 or less, still more preferably 0.5 or less, still more preferably 0.10 or less, still more preferably 0.07 or less. <32> A method for improving the elongation at break of a structural adhesive, which has a step of mixing a modified cellulose fiber and a urethane-modified epoxy resin. <33> An adhesive kit comprising a container containing the adhesive according to any one of <21> to <24>. <34> An adhesive kit comprising a first container containing the composition according to any one of <21> to <24> and a second container containing a curing agent.

Examples

[0150] Hereinafter, the present invention will be specifically described by showing examples and the like. Note that the following examples are merely illustrative of the present invention and do not mean any limitation. Here, "normal pressure" means 101.3 kPa, and "normal temperature" means 25°C.

[0151] 〔Average fiber diameter and average fiber length of cellulose fiber and anionic modified cellulose fiber〕 Deionized water was added to the cellulose fiber to be measured or the suspension containing the cellulose fiber to be measured to prepare a dispersion having a content rate of 0.01% by mass. Using a wet dispersion type image analysis particle size distribution meter (manufactured by JASCO International Co., Ltd., product name: IF-3200), the front lens: 2 times, telecentric zoom lens: 1 time, image resolution: 0.835 μm / pixel, syringe inner diameter: 6515 μm, spacer thickness: 500 μm, image recognition mode: ghost, threshold value: 8, analysis sample amount: 1 mL, sampling: 15% were measured. Then, when the cellulose fiber was approximated to a rectangle, the length of the short axis was taken as the fiber diameter and the length of the long axis was taken as the fiber length, and the respective values were measured for 100 cellulose fibers, and the average value was calculated.

[0152] 〔Average fiber diameter and average fiber length of cellulose fiber after refinement treatment〕 Deionized water or N,N-dimethylformamide (DMF) was added to the cellulose fibers to be measured or the dispersion containing the cellulose fibers to be measured to prepare a dispersion with a content of 0.0001% by mass. The dispersion was dropped onto mica and dried to obtain an observation sample. Using an atomic force microscope (AFM) (manufactured by Digital instrument, Nanoscope II Tappingmode AFM; the probe was manufactured by Nanoscensors, Point Probe (NCH)), the fiber height of the cellulose fibers in the observation sample (the height difference between the places with and without fibers) was measured. At this time, in the microscopic image where the cellulose fibers could be confirmed, 100 cellulose fibers were extracted, and the average fiber diameter was calculated from their fiber heights. The average fiber length was calculated from the distance in the fiber direction.

[0153] 〔Anionic group content of anionic modified cellulose fibers〕 0.5 g of the cellulose fibers to be measured with a dry mass was placed in a beaker, deionized water or a mixed solvent of methanol / deionized water = 2 / 1 (volume ratio) was added to make a total of 55 mL, and 5 mL of 0.01 M aqueous sodium chloride solution was added thereto to prepare a dispersion. The dispersion was stirred until the cellulose fibers to be measured were sufficiently dispersed. 0.1 M hydrochloric acid was added to this dispersion to adjust the pH to 2.5 - 3, and using an automatic titrator (manufactured by Toa DK Kogyo Co., Ltd., AUT-701), 0.05 M aqueous sodium hydroxide solution was dropped into the dispersion under the condition of a waiting time of 60 seconds, and the values of conductivity and pH every 1 minute were measured. The measurement was continued until the pH reached about 11 to obtain a conductivity curve. The titration amount of sodium hydroxide was determined from this conductivity curve, and the anionic group content of the cellulose fibers to be measured was calculated by the following formula. Anionic group content (mmol / g) = [Titration amount of aqueous sodium hydroxide solution (mL) × Concentration of aqueous sodium hydroxide solution (0.05 M)] / [Mass of cellulose fibers to be measured (0.5 g)]

[0154] 〔Bonding amount and introduction rate of modifying groups of modified cellulose fibers〕 The amount of bound modifying groups of the modified cellulose fiber was determined by the following IR measurement method, and the amount of bound modifying groups and the introduction rate were calculated by the following formula. Specifically, for the IR measurement, the infrared absorption spectrum of the dried cellulose fiber to be measured was measured by the ATR method using an infrared absorption spectrometer (IR) (Nicolet 6700, manufactured by Thermo Fisher Scientific), and the amount of bound modifying groups and the introduction rate were calculated by formula A. The following shows the case where the anionic group is a carboxyl group, that is, the case of oxidized cellulose fiber. In the following, the "peak intensity at 1720 cm -1 " is the peak intensity derived from the carbonyl group. In the case of an anionic group other than the carboxyl group, the value of the wave number may be appropriately changed to calculate the amount of bound modifying groups and the introduction rate. <Formula A> Amount of bound modifying groups (mmol / g) = a × (b - c) ÷ b a: Carboxyl group content of oxidized cellulose fiber (mmol / g) b: Peak intensity at 1720 cm of oxidized cellulose fiber -1 c: Peak intensity at 1720 cm of modified cellulose fiber -1 <Formula B> Introduction rate of modifying groups (mol%) = 100 × f / g f: Amount of bound modifying groups (mmol / g) g: Carboxyl group content of oxidized cellulose fiber (mmol / g)

[0155] 〔Contents of each component〕 The content of each component other than water was calculated from the blending amount of each component. Regarding the content of the glucose moiety, assuming that all of the anionic modified cellulose fiber and the modifying compound blended during the preparation of the modified cellulose fiber were ionically bonded, the mass of the anionic modified cellulose fiber contained in the blended modified cellulose fiber was regarded as the mass of the glucose moiety and calculated. In addition, the water content in the dispersion or suspension was measured by Karl Fischer titration using CA-200 manufactured by Mitsubishi Analytech Co., Ltd. In addition, the solid content concentration in various cellulose fibers was calculated from the difference from 100% by measuring the moisture concentration in the sample using an infrared moisture meter (manufactured by Shimadzu Corporation, MOC-120H). The moisture concentration was measured every 30 seconds at a constant temperature of 150°C for 1 g of the sample, and the numerical value displayed when the mass reduction within 30 seconds became 0.1% or less was used.

[0156] 〔Confirmation of Crystal Structure in Modified Cellulose Fibers〕 The crystal structure of the modified cellulose fibers was confirmed by measuring under the following conditions using an X-ray diffractometer (manufactured by Rigaku Corporation, MiniFlexII). The measurement conditions were as follows: X-ray source: Cu / Kα-radiation, tube voltage: 30 kv, tube current: 15 mA, measurement range: diffraction angle 2θ = 5 to 45°, X-ray scan speed: 10° / min. As the sample for measurement, the cellulose fibers to be measured were compressed into a pellet with an area of 320 mm 2 × thickness of 1 mm. In addition, the crystallinity of the cellulose I-type crystal structure was calculated based on the following formula C using the obtained X-ray diffraction intensity.

[0157] <Formula C> Cellulose I-type crystallinity (%) = [(I 22.6 - I 18.5 ) / I 22.6 × 100 〔In the formula, I 22.6 represents the diffraction intensity of the lattice plane (002 plane) (diffraction angle 2θ = 22.6°) in X-ray diffraction, and I 18.5 represents the diffraction intensity of the amorphous part (diffraction angle 2θ = 18.5°).〕

[0158] On the other hand, when the crystallinity obtained by the above formula C is 35% or less, from the viewpoint of improving the calculation accuracy, it is preferable to calculate based on the following formula D in accordance with the description on P199-200 of the "Manual of Wood Science Experiments" (edited by the Japanese Wood Research Society; published in April 2000). Therefore, when the crystallinity obtained by the above formula C is 35% or less, the value calculated based on the following formula D can be used as the crystallinity.

[0159] <Formula D> Degree of crystallinity of cellulose type I (%) = [A c / (A c + A a )] × 100 [In the formula, A c is the sum of the peak areas of the lattice planes (002 plane) (diffraction angle 2θ = 22.6°), (011 plane) (diffraction angle 2θ = 15.1°), and (0-11 plane) (diffraction angle 2θ = 16.2°) in X-ray diffraction, A a represents the peak area of the amorphous part (diffraction angle 2θ = 18.5°), and each peak area is obtained by fitting the obtained X-ray diffraction chart with a Gaussian function.]

[0160] [Cellulose fiber (converted amount) in the modified cellulose fiber] The amount of cellulose (converted amount) in the modified cellulose fiber is the amount of cellulose excluding the modifying group in the modified cellulose fiber. In the present invention, since the formula weight of the modifying group in the modified cellulose fiber may be considerably large (for example, larger than the molecular weight of glucose), in this specification, when it is more appropriate to explain by excluding the difference in the formula weight of the modifying group, it is expressed not by the amount of the modified cellulose fiber but by the amount of cellulose (converted amount) constituting the modified cellulose fiber. The cellulose fiber (converted amount) in the modified cellulose fiber was measured by the following method.

[0161] (1) When one type of "modifying compound" is added The amount of cellulose fiber (converted amount) was calculated by the following formula E. <Formula E> Amount of cellulose fiber (converted amount) (g) = mass of modified cellulose fiber (g) / [1 + molecular weight of modifying compound (g / mol) × binding amount of modifying group (mmol / g) × 0.001] (2) When two or more types of "modifying compounds" are added Considering the molar ratio of each compound (that is, the molar ratio when the total molar amount of the added compounds is 1), the amount of cellulose fiber (converted amount) was calculated.

[0162] Production Example 1 [Production of anionic modified cellulose fiber] As the raw material of component (A), anionic modified cellulose fiber 1 having the physical property values shown in Table 1 was used.

[0163] [Table 1]

[0164] Such anionic modified cellulose fiber 1 can be prepared, for example, by performing the following TEMPO oxidation treatment.

[0165] [TEMPO Oxidation Treatment] Weigh 20 g of softwood bleached kraft pulp fiber as the raw natural cellulose fiber and 1980 g of deionized water into a 2 L PP beaker equipped with a mechanical stirrer and a stirring blade, and stir at 25 °C and 100 rpm for 30 minutes. Next, 0.26 g of 2,2,6,6 - tetramethyl - 1 - piperidine - N - oxyl (TEMPO), 2.6 g of sodium bromide, and 70.0 g of a 10.5 mass% aqueous sodium hypochlorite solution are added to the 20 g of the pulp fiber in this order. Next, pH - stat titration is performed using an automatic titrator, and a 0.5 M aqueous sodium hydroxide solution is added dropwise to maintain the pH at 10.5. The reaction is carried out at 25 °C for 120 minutes at a stirring speed of 100 rpm. Then, while stirring, 0.01 M hydrochloric acid is added thereto to make the pH of the suspension 2. Then, the solid content is separated by suction filtration. The operation of dispersing the solid content in deionized water and separating the solid content by suction filtration is repeated until the conductivity of the filtrate becomes 200 μS / cm or less. The obtained solid content is subjected to a dehydration treatment to obtain an anionic modified cellulose fiber.

[0166] Production Example 2 [Production of Modified Cellulose Fibers 2A and 2B] To 227 g (solid content: 75 g) of the cake of anionic modified cellulose fiber 1 in Production Example 1, 1 - methoxy - 2 - propanol (PGME) was added to obtain dispersion liquids A (solid content concentration: 2.0 mass%) and B (solid content concentration: 5.0 mass%) of two kinds of concentrations of anionic modified cellulose fiber in a state swollen in PGME. For each of the obtained dispersions, an amine (the following EO / PO amine) was added so as to have the compounding amounts described in Table 2A, and the mixture was stirred at 25°C for 1 hour to obtain dispersions of modified cellulose fibers 2A and 2B having a modifying group via an ionic bond.

[0167] EO / PO amine: Methoxypoly(oxyethylene / oxypropylene)-2-propylamine (manufactured by Huntsman, Jeffamine M2070, Mw = 2,000, EO:PO = 31:10)

[0168]

Table 2A

[0169] Production Example 3 [Production of Short-Fiberized Modified Cellulose Fibers 3A and 3B] To 227 g (solid content: 75 g) of the cake of the anionic-modified cellulose fiber 1 obtained in Production Example 1, deionized water was added until the solid content concentration became 5% by mass from the value shown in Table 1. The obtained suspension was stirred at 95°C for 12 hours to obtain an aqueous suspension of short-fiberized anionic-modified cellulose fibers. The obtained suspension was centrifuged using a high-speed cooling centrifuge (manufactured by Koki Holdings Co., Ltd., CR21G III) under the conditions of 25°C, 10,000 G, and 1 minute to obtain 85 g of a dispersion of short-fiberized anionic-modified cellulose fibers (solid content concentration: 23.5% by mass) as a precipitate.

[0170] Thereafter, the solvent was replaced with PGME to obtain dispersions A (solid content concentration: 2.0%) and B (solid content concentration: 5.0%) of short-fiberized anionic-modified cellulose fibers in a state of being swollen in PGME. For each of the obtained dispersions, an amine (the above EO / PO amine) was added so as to have the compounding amounts described in Table 2B, and the mixture was stirred at 25°C for 1 hour to obtain dispersions of short-fiberized modified cellulose fibers 3A and 3B having a modifying group via an ionic bond.

[0171]

Table 2B

[0172] Production Example 4 (Production of Short-Fiberized Modified Cellulose Fiber 4) In the same manner as in Production Example 3, a dispersion of short-fiberized anionic modified cellulose fiber in a swollen state in PGME (solid content concentration: 5.0%) was obtained. To 21.4 g of the obtained dispersion, 0.07 g of octylamine (manufactured by Kao Corporation, Octylamine, Farmine 08D) was mixed, and the mixture was stirred at 25°C for 1 hour to obtain a dispersion of short-fiberized modified cellulose fiber 4.

[0173] Production Example 5 [Production of Unmodified Cellulose Fiber] The dispersion of short-fiberized anionic modified cellulose fiber in a swollen state in PGME (solid content concentration: 5.0%), which is an intermediate product of Production Example 3, was stirred at 25°C for 1 hour to obtain a dispersion of unmodified anionic modified cellulose fiber 5.

[0174] Production Examples 6 to 8 [Production of Minimized Modified Cellulose Fiber] The dispersion of modified cellulose fiber 2A obtained in Production Example 2 was stirred at 25°C for 1 hour, and then subjected to dispersion treatment 5 times at 150 MPa using a high-pressure homogenizer (manufactured by Yoshida Kikai Kogyo Co., Ltd., Nanoveta L-ES) to obtain a dispersion of minimized modified cellulose fiber 6. For each of the modified cellulose fibers obtained in Production Examples 3 to 4, the same dispersion treatment as described above was performed to obtain dispersions of minimized modified cellulose fibers 7 to 8. The average fiber diameter and average fiber length of each of the minimized modified cellulose fibers 6 to 8 and the unmodified cellulose fiber of Production Example 5 are shown in Table 2C.

[0175]

Table 2C

[0176] Example 1 (Production of Resin Composition) (a) Step 1 100 g of the PGME dispersion of the short-fiberized modified cellulose fiber 3A obtained in Production Example 3 (cellulose solid content concentration: 2.0%) and 100 g of the urethane-modified epoxy resin were stirred at 25°C for 1 hour. Subsequently, using a high-pressure homogenizer (manufactured by Yoshida Kikai Kogyo Co., Ltd., Nanoveta L-ES), this was subjected to dispersion treatment 5 times at 150 MPa. Thereafter, the solvent was distilled off using an evaporator to obtain a mixture containing the modified cellulose fiber and the urethane-modified epoxy resin.

[0177] Conditions of the evaporator Water bath temperature: 75°C Degree of vacuum (absolute pressure): 0 to 1 kPa Judgment of the end of distillation: Judged by the fact that there was a mass reduction corresponding to the blending amount of water and the organic solvent.

[0178] (b) Step 2 Next, 150 g of a bisphenol A-type epoxy resin was added to 103 g of this mixture, and it was stirred at 25°C for 10 minutes using a planetary mixer (manufactured by Primix Corporation, Hibismix 2P-1 type) to obtain a mixture containing the modified cellulose fiber, the urethane-modified epoxy resin, and the epoxy resin.

[0179] (c) Step A Next, 15 g of dicyandiamide (a heavy addition-type curing agent, manufactured by Mitsubishi Chemical Corporation: DICY7) and 5 g of 3-(3,4-dichlorophenyl)-1,1-dimethylurea (a curing accelerator, manufactured by Hodogaya Chemical Co., Ltd.: DCMU99) were added to 253 g of this mixture, and it was stirred at 25°C for 1 hour using the same planetary mixer to obtain a mixture containing the modified cellulose fiber, the urethane-modified epoxy resin, the epoxy resin, and the curing agent.

[0180] (d) Step B Next, 25 g of polypropylene glycidyl ether (a reactive diluent) was added to 273 g of this mixture, and after stirring at 25°C for 10 minutes using the same planetary mixer, degassing was performed under reduced pressure (1,840 Pa) for 1 hour to produce a resin composition.

[0181] Example 2 (Production of resin composition) (a) Step 1 Using the PGME dispersion of the short fiber-reinforced modified cellulose fiber 3B obtained in Production Example 3 (cellulose solid content concentration: 5.0%), Step 1 was carried out in the same manner as in Example 1 to obtain a mixture containing the modified cellulose fiber and the urethane-modified epoxy resin.

[0182] (b) Step 2 Next, 150 g of bisphenol A type epoxy resin was added to 108 g of this mixture, and it was stirred at 25 °C for 10 minutes using a planetary mixer (manufactured by Primix Corporation, Hibiscus Mix 2P-1 type) to obtain a mixture containing the modified cellulose fiber, the urethane-modified epoxy resin, and the epoxy resin.

[0183] (c) Step A Next, 15 g of dicyandiamide (polyaddition type curing agent, manufactured by Mitsubishi Chemical Corporation: DICY7) and 5 g of 3-(3,4-dichlorophenyl)-1,1-dimethylurea (curing accelerator, manufactured by Hodogaya Chemical Co., Ltd.: DCMU99) were added to 258 g of this mixture, and it was stirred at 25 °C for 1 hour using the same planetary mixer to obtain a mixture containing the modified cellulose fiber, the urethane-modified epoxy resin, the epoxy resin, and the curing agent.

[0184] (d) Step B Next, 25 g of polypropylene glycidyl ether (reactive diluent) was added to 278 g of this mixture, and it was stirred at 25 °C for 10 minutes using the same planetary mixer, and then degassed under reduced pressure (1,840 Pa) for 1 hour to produce a resin composition.

[0185] Example 3 (Production of Resin Composition) (a) Step 5 100 g of the PGME dispersion of the short-fiberized modified cellulose fiber 3A obtained in Production Example 3 (cellulose solid content concentration: 2.0%) and 100 g of a bisphenol A-type epoxy resin were stirred at 25°C for 1 hour. Next, using a high-pressure homogenizer (manufactured by Yoshida Kikai Kogyo Co., Ltd., Nanoveta L-ES), this was subjected to dispersion treatment 5 times at 150 MPa. Thereafter, the solvent was distilled off using an evaporator to obtain a mixture containing the modified cellulose fiber and the bisphenol A-type epoxy resin.

[0186] (b) Step 6 Next, 67 g of a urethane-modified epoxy resin was added to 103 g of this mixture, and it was stirred at 25°C for 10 minutes using a planetary mixer (manufactured by Primix Corporation, Hibis Mix 2P-1 type) to obtain a mixture containing the modified cellulose fiber, the epoxy resin, and the urethane-modified epoxy resin.

[0187] (c) Step A Next, 10 g of dicyandiamide (a polyaddition-type curing agent, manufactured by Mitsubishi Chemical Corporation: DICY7) and 3 g of 3-(3,4-dichlorophenyl)-1,1-dimethylurea (a curing accelerator, manufactured by Hodogaya Chemical Co., Ltd.: DCMU99) were added to 170 g of this mixture, and it was stirred at 25°C for 1 hour using the same planetary mixer to obtain a mixture containing the modified cellulose fiber, the epoxy resin, the urethane-modified epoxy resin, and the curing agent.

[0188] (d) Step B Next, 17 g of polypropylene glycidyl ether (a reactive diluent) was added to 183 g of this mixture, and after stirring at 25°C for 10 minutes using the same planetary mixer, defoaming was carried out under reduced pressure (1,840 Pa) for 1 hour to produce a resin composition.

[0189] Example 4 (Production of Resin Composition) (a) Step 3 100 g of the PGME dispersion of the short-fiberized modified cellulose fiber 3B obtained in Production Example 3 (cellulose solid content concentration: 5.0%), 60 g of bisphenol A-type epoxy resin, and 40 g of urethane-modified epoxy resin were stirred at 25°C for 1 hour. Next, using a high-pressure homogenizer (manufactured by Yoshida Kikai Kogyo Co., Ltd., Nanoveta L-ES), this was subjected to dispersion treatment 5 times at 150 MPa. Thereafter, the solvent was distilled off using an evaporator to obtain a mixture containing the modified cellulose fiber, bisphenol A-type epoxy resin, and urethane-modified epoxy resin.

[0190] (b) Step A Next, 6 g of dicyandiamide (polyaddition-type curing agent, manufactured by Mitsubishi Chemical Corporation: DICY7) and 2 g of 3-(3,4-dichlorophenyl)-1,1-dimethylurea (curing accelerator, manufactured by Hodogaya Chemical Co., Ltd.: DCMU99) were added to 108 g of this mixture, and it was stirred at 25°C for 1 hour using the same planetary mixer to obtain a mixture containing the modified cellulose fiber, epoxy resin, urethane-modified epoxy resin, and curing agent.

[0191] (c) Step B Next, 10 g of polypropylene glycidyl ether (reactive diluent) was added to 116 g of this mixture, and after stirring at 25°C for 10 minutes using the same planetary mixer, degassing was carried out under reduced pressure (1,840 Pa) for 1 hour to produce a resin composition.

[0192] Comparative Example 1 In the resin composition of Example 1, a resin composition not using the modified cellulose fiber was prepared as Comparative Example 1. That is, 100 g of urethane-modified epoxy resin and 150 g of bisphenol A-type epoxy resin were added, and they were stirred at 25°C for 10 minutes using a planetary mixer (manufactured by Primix Corporation, High Bismix 2P-1 type) to obtain a mixture containing the urethane-modified epoxy resin and epoxy resin. Next, 15 g of dicyandiamide (polyaddition-type curing agent) and 5 g of 3-(3,4-dichlorophenyl)-1,1-dimethylurea (curing accelerator, manufactured by Hodogaya Chemical Co., Ltd.: DCMU99) were added to 250 g of this mixture, and the mixture was stirred at 25°C for 1 hour using the same planetary mixer. Then, 25 g of polypropylene glycidyl ether (reactive diluent) was added to 270 g of this mixture, and after stirring at 25°C for 10 minutes using the same planetary mixer, degassing was performed under reduced pressure (1,840 Pa) for 1 hour to produce a resin composition.

[0193] Example 5 (Production of Resin Composition) (a) Step 1 In the same manner as in Step 1 of Example 1, a mixture containing modified cellulose fibers and urethane-modified epoxy resin was obtained.

[0194] (b) Step 2 Next, in the same manner as in Step 2 of Example 1, a mixture containing modified cellulose fibers, urethane-modified epoxy resin, and epoxy resin was obtained.

[0195] (c) Step α Next, 150 g of calcium carbonate (filler) was added to 253 g of this mixture, and the mixture was stirred at 25°C for 10 minutes using the same planetary mixer. Subsequently, 17.5 g of hydrophobized silica (filler) was added, and the mixture was stirred at 25°C for an additional 10 minutes. Subsequently, 10 g of calcium oxide (filler) was added, and the mixture was stirred at 25°C for an additional 10 minutes to obtain a mixture containing modified cellulose fibers, urethane-modified epoxy resin, epoxy resin, and various fillers.

[0196] (d) Step A Next, 15 g of dicyandiamide (polyaddition-type curing agent, manufactured by Mitsubishi Chemical Corporation: DICY7) and 5 g of 3-(3,4-dichlorophenyl)-1,1-dimethylurea (curing accelerator, manufactured by Hodogaya Chemical Co., Ltd.: DCMU99) were added to 430.5 g of this mixture, and the mixture was stirred at 25°C for 1 hour using the same planetary mixer to obtain a mixture containing modified cellulose fibers, urethane-modified epoxy resin, epoxy resin, various fillers, and a curing agent.

[0197] (e) Process B Next, 25 g of polypropylene glycidyl ether (reactive diluent) was added to 450.5 g of this mixture, and after stirring at 25°C for 10 minutes using the same planetary mixer, degassing was carried out under reduced pressure (1,840 Pa) for 1 hour to produce a resin composition.

[0198] Example 6 (Production of Resin Composition) (a) Process 1 A mixture containing modified cellulose fiber and urethane-modified epoxy resin was obtained in the same manner as in Process 1 of Example 2.

[0199] (b) Process 2 A mixture containing modified cellulose fiber, urethane-modified epoxy resin, and epoxy resin was obtained in the same manner as in Process 2 of Example 2. (c) Process α Next, various fillers blended in Process α of Example 5 were similarly blended into the mixture containing modified cellulose fiber, urethane-modified epoxy resin, and epoxy resin to obtain a mixture containing modified cellulose fiber, urethane-modified epoxy resin, epoxy resin, and various fillers. (d) Process A A mixture containing modified cellulose fiber, urethane-modified epoxy resin, epoxy resin, various fillers, and a curing agent was obtained in the same manner as in Process A of Example 2. (e) Process B A resin composition was produced in the same manner as in Process B of Example 2.

[0200] Example 7 (Production of Resin Composition) (a) Process 5 A mixture containing modified cellulose fiber and bisphenol A type epoxy resin was obtained in the same manner as in Process 5 of Example 3.

[0201] (b) Process 6 A mixture containing modified cellulose fiber, epoxy resin, and urethane-modified epoxy resin was obtained in the same manner as in Process 6 of Example 3. (c) Process α Next, various fillers blended in Step α of Example 5 were similarly blended into a mixture containing modified cellulose fibers, urethane-modified epoxy resin, and epoxy resin to obtain a mixture containing modified cellulose fibers, urethane-modified epoxy resin, epoxy resin, and various fillers. (d) Step A In the same manner as in Step A of Example 3, a mixture containing modified cellulose fibers, urethane-modified epoxy resin, epoxy resin, various fillers, and a curing agent was obtained. (e) Step B A resin composition was produced in the same manner as in Step B of Example 3.

[0202] Example 8 (Production of Resin Composition) (a) Step 3 In the same manner as in Step 3 of Example 4, a mixture containing modified cellulose fibers and bisphenol A-type epoxy resin was obtained.

[0203] (b) Step 6 In the same manner as in Step 6 of Example 3, a mixture containing modified cellulose fibers, bisphenol A-type epoxy resin, and urethane-modified epoxy resin was obtained. (c) Step α Next, various fillers blended in Step α of Example 5 were similarly blended into a mixture containing modified cellulose fibers, urethane-modified epoxy resin, and epoxy resin to obtain a mixture containing modified cellulose fibers, urethane-modified epoxy resin, epoxy resin, and various fillers. (d) Step A In the same manner as in Step A of Example 4, a mixture containing modified cellulose fibers, urethane-modified epoxy resin, epoxy resin, various fillers, and a curing agent was obtained. (e) Step B A resin composition was produced in the same manner as in Step B of Example 4.

[0204] Comparative Example 2 In the resin composition of Example 5, a resin composition not using modified cellulose fibers was prepared as Comparative Example 2. 100 g of urethane-modified epoxy resin and 150 g of bisphenol A-type epoxy resin were mixed and stirred at 25°C for 10 minutes using a planetary mixer (manufactured by Primix Corporation, Hibiscus Mix 2P-1 type) to obtain a mixture containing modified cellulose fiber, urethane-modified epoxy resin, and epoxy resin. Next, 150 g of calcium carbonate (filler) was added to 250 g of this mixture, and the mixture was stirred at 25°C for 10 minutes using the same planetary mixer. Subsequently, 17.5 g of hydrophobized silica (filler) was added, and the mixture was further stirred at 25°C for 10 minutes. Subsequently, 10 g of calcium oxide (filler) was added, and the mixture was further stirred at 25°C for 10 minutes to obtain a mixture containing modified cellulose fiber, urethane-modified epoxy resin, epoxy resin, and various fillers.

[0205] Next, 15 g of dicyandiamide (polyaddition-type curing agent, manufactured by Mitsubishi Chemical Corporation: DICY7) and 5 g of 3-(3,4-dichlorophenyl)-1,1-dimethylurea (curing accelerator, manufactured by Hodogaya Chemical Co., Ltd.: DCMU99) were added to 427.5 g of this mixture, and the mixture was stirred at 25°C for 1 hour using the same planetary mixer to obtain a mixture containing urethane-modified epoxy resin, epoxy resin, various fillers, and a curing agent.

[0206] Next, 25 g of polypropylene glycidyl ether (reactive diluent) was added to 447.5 g of this mixture, and the mixture was stirred at 25°C for 10 minutes using the same planetary mixer, and then degassed under reduced pressure (1,840 Pa) for 1 hour to produce a resin composition.

[0207] Example 9 (Production of Resin Composition) (a) Step 1 Using the PGME dispersion of the short-fiberized modified cellulose fiber 4 (cellulose solid content concentration: 5.0%) obtained in Production Example 4, Step 1 was carried out in the same manner as in Example 1 to obtain a mixture containing modified cellulose fiber and urethane-modified epoxy resin.

[0208] (b) Step 2 Next, the same operation as in Step 2 of Example 2 was performed on 105 g of this mixture to obtain a mixture containing a modified cellulose fiber, a urethane-modified epoxy resin, and an epoxy resin.

[0209] (c) Step A Next, the same operation as in Step A of Example 2 was performed on 255 g of this mixture to obtain a mixture containing a modified cellulose fiber, a urethane-modified epoxy resin, an epoxy resin, and a curing agent.

[0210] (d) Step B Next, the same operation as in Step B of Example 2 was performed on 275 g of this mixture to produce a resin composition.

[0211] Example 10 (Production of Resin Composition) (a) Step 1 100 g of a PGME dispersion (cellulose solid content concentration: 5.0%) of the short-fiberized modified cellulose fiber 3B obtained in Production Example 3 and 150 g of a urethane-modified epoxy resin were stirred at 25°C for 1 hour. Next, using a high-pressure homogenizer (manufactured by Yoshida Kikai Kogyo Co., Ltd., Nanoveta L-ES), this was subjected to dispersion treatment 5 times at 150 MPa. Thereafter, the solvent was distilled off by an evaporator to obtain a mixture containing a modified cellulose fiber and a urethane-modified epoxy resin.

[0212] (b) Step 2 Next, 100 g of a bisphenol A type epoxy resin was added to 158 g of this mixture, and the mixture was stirred at 25°C for 10 minutes using a planetary mixer (manufactured by Primix Corporation, Hibismix 2P-1 type) to obtain a mixture containing a modified cellulose fiber, a urethane-modified epoxy resin, and an epoxy resin.

[0213] (c) Step A Next, the same operation as in Step A of Example 2 was performed on 258 g of this mixture to obtain a mixture containing a modified cellulose fiber, a urethane-modified epoxy resin, an epoxy resin, and a curing agent.

[0214] (d) Step B Next, the same operation as in Step B of Example 2 was performed on 278 g of this mixture to produce a resin composition.

[0215] Example 11 (Production of Resin Composition) (a) Step 1 100 g of a PGME dispersion of the short-fiberized modified cellulose fiber 3B obtained in Production Example 3 (cellulose solid content concentration: 5.0%) and 25 g of a urethane-modified epoxy resin were stirred at 25°C for 1 hour. Next, using a high-pressure homogenizer (manufactured by Yoshida Kikai Kogyo Co., Ltd., Nanoveta L-ES), this was subjected to dispersion treatment 5 times at 150 MPa. Thereafter, the solvent was distilled off by an evaporator to obtain a mixture containing a modified cellulose fiber and a urethane-modified epoxy resin.

[0216] (b) Step 2 Next, 225 g of a bisphenol A type epoxy resin was added to 33 g of this mixture, and it was stirred at 25°C for 10 minutes using a planetary mixer (manufactured by Primix Corporation, Hibimix 2P-1 type) to obtain a mixture containing a modified cellulose fiber, a urethane-modified epoxy resin, and an epoxy resin.

[0217] (c) Step A Next, the same operation as in Step A of Example 2 was performed on 258 g of this mixture to obtain a mixture containing a modified cellulose fiber, a urethane-modified epoxy resin, an epoxy resin, and a curing agent.

[0218] (d) Step B Next, the same operation as in Step B of Example 2 was performed on 278 g of this mixture to produce a resin composition.

[0219] Example 12 (Production of Resin Composition) A resin composition was produced in the same manner as in Example 2, except that a PGME dispersion of the modified cellulose fiber 2B obtained in Production Example 2 (cellulose solid content concentration: 5.0%) was used instead of the PGME dispersion of the short-fiberized modified cellulose fiber 3B obtained in Production Example 3.

[0220] Comparative Example 3 (Manufacture of Resin Composition) A resin composition was manufactured in the same manner as in Example 2, except that the PGME dispersion of the non-modified cellulose fiber of Production Example 5 was used instead of the PGME dispersion of the short-fiberized modified cellulose fiber 3B obtained in Production Example 3 (cellulose solid content concentration: 5.0%).

[0221] Comparative Example 4 (Manufacture of Resin Composition) (a) Step 1 100 g of the PGME dispersion of the short-fiberized modified cellulose fiber 3B obtained in Production Example 3 (cellulose solid content concentration: 5.0%) and 100 g of a bisphenol A type epoxy resin were stirred at 25°C for 1 hour. Next, this was subjected to dispersion treatment 5 times at 150 MPa using a high-pressure homogenizer (manufactured by Yoshida Kikai Kogyo Co., Ltd., Nanoveta L-ES). Thereafter, the solvent was distilled off by an evaporator to obtain a mixture containing the modified cellulose fiber and the bisphenol A type epoxy resin.

[0222] (b) Step 2 Next, 150 g of the bisphenol A type epoxy resin was added to 108 g of this mixture, and the mixture was stirred at 25°C for 10 minutes using a planetary mixer (manufactured by Primix Corporation, High Bismix 2P-1 type) to obtain a mixture containing the modified cellulose fiber and the epoxy resin.

[0223] (c) Step A Next, the same operation as in Step A of Example 2 was performed on 258 g of this mixture to obtain a mixture containing the modified cellulose fiber, the epoxy resin, and the curing agent.

[0224] (d) Step B Next, the same operation as in Step B of Example 2 was performed on 278 g of this mixture to manufacture a resin composition.

[0225] The compositions of the resin compositions in Examples 1 to 4, 9 to 12 and Comparative Examples 1, 3 to 4 are summarized in Table 3.

[0226] [Table 3]

[0227] *: The average fiber length of the modified cellulose fibers in the table was cited from the average fiber length of the corresponding micronized modified cellulose fibers described in Table 2C.

[0228] Example 13 (Manufacture of Resin Composition) (a) Step 1 In the same manner as in Step 1 of Example 9, a mixture containing modified cellulose fibers and a urethane-modified epoxy resin was obtained.

[0229] (b) Step 2 In the same manner as in Step 2 of Example 9, a mixture containing modified cellulose fibers, a urethane-modified epoxy resin, and an epoxy resin was obtained. (c) Step α Next, various fillers compounded in Step α of Example 5 were similarly compounded into the mixture containing modified cellulose fibers, a urethane-modified epoxy resin, and an epoxy resin to obtain a mixture containing modified cellulose fibers, a urethane-modified epoxy resin, an epoxy resin, and various fillers. (d) Step A Next, in the same manner as in Step A of Example 9, a mixture containing modified cellulose fibers, a urethane-modified epoxy resin, an epoxy resin, various fillers, and a curing agent was obtained. (e) Step B Next, a resin composition was manufactured in the same manner as in Step B of Example 9.

[0230] Example 14 (Manufacture of Resin Composition) (a) Step 1 In the same manner as in Step 1 of Example 10, a mixture containing modified cellulose fibers and a urethane-modified epoxy resin was obtained.

[0231] (b) Step 2 In the same manner as in Step 2 of Example 10, a mixture containing modified cellulose fibers, a urethane-modified epoxy resin, and an epoxy resin was obtained. (c) Step α Next, various fillers compounded in Step α of Example 5 were similarly compounded into a mixture containing modified cellulose fibers, urethane-modified epoxy resin, and epoxy resin to obtain a mixture containing modified cellulose fibers, urethane-modified epoxy resin, epoxy resin, and various fillers. (d) Step A Next, a mixture containing modified cellulose fibers, urethane-modified epoxy resin, epoxy resin, various fillers, and a curing agent was obtained in the same manner as in Step A of Example 10. (e) Step B Next, a resin composition was produced in the same manner as in Step B of Example 10.

[0232] Example 15 (Production of Resin Composition) (a) Step 1 A mixture containing modified cellulose fibers and urethane-modified epoxy resin was obtained in the same manner as in Step 1 of Example 11.

[0233] (b) Step 2 A mixture containing modified cellulose fibers, urethane-modified epoxy resin, and epoxy resin was obtained in the same manner as in Step 2 of Example 11. (c) Step α Next, various fillers compounded in Step α of Example 5 were similarly compounded into a mixture containing modified cellulose fibers, urethane-modified epoxy resin, and epoxy resin to obtain a mixture containing modified cellulose fibers, urethane-modified epoxy resin, epoxy resin, and various fillers. (d) Step A Next, a mixture containing modified cellulose fibers, urethane-modified epoxy resin, epoxy resin, various fillers, and a curing agent was obtained in the same manner as in Step A of Example 11. (e) Step B Next, a resin composition was produced in the same manner as in Step B of Example 11.

[0234] Example 16 (Production of Resin Composition) Instead of using the PGME dispersion of the short-fiberized modified cellulose fiber 3B obtained in Production Example 3 (cellulose solid content concentration: 5.0%), the same operations as in Example 6 were carried out except that the PGME dispersion of the modified cellulose fiber 2B obtained in Production Example 2 (cellulose solid content concentration: 5.0%) was used to produce a resin composition.

[0235] Comparative Example 5 (Production of resin composition) Instead of using the PGME dispersion of the short-fiberized modified cellulose fiber 3B obtained in Production Example 3 (cellulose solid content concentration: 5.0%), the same operations as in Example 6 were carried out except that the PGME dispersion of the unmodified cellulose fiber of Production Example 5 was used to produce a resin composition.

[0236] Comparative Example 6 (Production of resin composition) (a) Step 1 100 g of the PGME dispersion of the short-fiberized modified cellulose fiber 3B obtained in Production Example 3 (cellulose solid content concentration: 5.0%) and 100 g of a bisphenol A type epoxy resin were stirred at 25°C for 1 hour. Next, using a high-pressure homogenizer (manufactured by Yoshida Kikai Kogyo Co., Ltd., Nanoveta L-ES), this was subjected to dispersion treatment 5 times at 150 MPa. Thereafter, the solvent was distilled off by an evaporator to obtain a mixture containing the modified cellulose fiber and the bisphenol A type epoxy resin.

[0237] (b) Step 2 Next, 150 g of the bisphenol A type epoxy resin was added to 108 g of this mixture, and it was stirred at 25°C for 10 minutes using a planetary mixer (manufactured by Primix Corporation, Hibimix 2P-1 type) to obtain a mixture containing the modified cellulose fiber and the epoxy resin.

[0238] (c) Step α Next, the various fillers blended in Step α of Example 5 were similarly blended into the mixture containing the modified cellulose fiber and the epoxy resin to obtain a mixture containing the modified cellulose fiber, the epoxy resin, and the various fillers. (d) Step A Next, the same operation as in Step A of Example 6 was performed on 435.5 g of this mixture to obtain a mixture containing a modified cellulose fiber, an epoxy resin, and a curing agent. (e) Step B Next, the same operation as in Step B of Example 6 was performed on 455.5 g of this mixture to produce a resin composition.

[0239] The compositions of the resin compositions in Examples 5 to 8, 13 to 16 and Comparative Examples 2, 5 to 6 are summarized in Table 4.

[0240] [Table 4]

[0241] *: The average fiber length of the modified cellulose fiber in the table cited the average fiber length of the corresponding micronized modified cellulose fiber described in Table 2C.

[0242] Details of the main components used in the above Production Examples, Examples, etc. are as follows. Urethane-modified epoxy resin (manufactured by ADEKA Corporation, urethane-modified epoxy resin, Adeka Resin, EPU-1001, viscosity 30,000 mP·s / 25°C, epoxy equivalent 220) Bisphenol A type epoxy resin (manufactured by Mitsubishi Chemical Corporation, bisphenol A type epoxy resin, jER828, viscosity 120 - 150 P / 25°C, epoxy equivalent 184 - 194; this resin is an epoxy resin other than the urethane-modified epoxy resin in Examples, etc.) Polypropylene glycol glycidyl ether (manufactured by ADEKA Corporation, Adeka Glycilol ED-506)

[0243] Details of the fillers used in the above Examples, etc. are as follows. Calcium carbonate (manufactured by Bihoku Powder Chemical Industry Co., Ltd., heavy calcium carbonate BF200) Hydrophobic silica (manufactured by Cabot Specialty Chemicals Inc., TS720) Calcium oxide (manufactured by Inoue Lime Industry Co., Ltd., QC-X)

[0244] For the compositions obtained in Examples 1 to 16 and Comparative Examples 1 to 6 above, the tests described in Test Example 1 below were conducted. Further, for the compositions obtained in Examples 1 to 12 and Comparative Examples 1 to 4, the tests described in Test Example 2 below were also conducted.

[0245] Test Example 1 (Shear Adhesion Strength Test: Adhesion of the Same Kind) In accordance with the shear strength test method described in JASO M353, the obtained resin composition was applied to a steel plate such that the coating thickness was 0.15 mm and the overlap of two cold-rolled steel plates SPCC-SD (100 mm × 25 mm × 1.6 mm), which served as the adherend, i.e., the adhesion surface, was 12.5 mm. After removing the composition that protruded from the steel plate, it was heat-cured under the conditions of holding at 130°C for 2 hours to prepare a shear test piece. The obtained test piece was tested using a tabletop precision universal testing machine (manufactured by Shimadzu Corporation, AGS-X) at a chuck distance of 111.5 cm, at room temperature (25°C), and at a tensile speed of 5 mm / min.

[0246] Note that the surface treatment method of the cold-rolled steel plate SPCC-SD used here, in accordance with the surface treatment method of the test piece material described in JASO M353, was to degrease the steel plate with acetone, dry it, immerse it in rust preventive oil (WD-40), and then leave it for 24 hours to drain the oil before use.

[0247] Test Example 2 (Tensile Test) The obtained resin composition was applied using an applicator to a thickness of 0.15 mm and heat-cured under the conditions of holding at 130°C for 2 hours to prepare a resin film. The obtained resin film was punched out with a dumbbell to obtain a test piece with a length of 40 mm and a width of 5 mm. The obtained test piece was tested using a tensile compression testing machine (manufactured by Shimadzu Corporation, AGS-X) in accordance with JIS K 7127 at a chuck distance of 20 mm, at room temperature (25°C), and at a tensile speed of 1 mm / min to measure the elongation at break (%), the maximum stress (MPa), and the fracture energy (kJ / m 2 )). Note that the thickness of the sample was the average value at three locations of the test piece.

[0248] The results are shown in Tables 5 and 6.

[0249] [Table 5]

[0250] From the comparison between the compositions containing the modified cellulose fiber (Examples 1 to 4) and the composition not containing the modified cellulose fiber (Comparative Example 1), it was found that when the resin composition contains the modified cellulose fiber, various physical properties of the cured resin, particularly elongation, were improved. Furthermore, it was found that such an effect is exhibited even when the type of the modifying group (compound for the modifying group) in the modified cellulose fiber is changed, the average fiber length is changed, or the ratio of resin (B) to resin (C) is changed. Since the resin composition of the present invention has such an effect, it has been demonstrated that the resin composition of the present invention can be used as a structural adhesive.

[0251] [Table 6]

[0252] From the above table, it was confirmed that in the compositions to which the filler was added (Examples 5 to 8 and Examples 13 to 16), the same effects as those shown in Examples 1 to 4 and Examples 9 to 12 were obtained.

[0253] Production Example 11 [Production of Anion-Modified Cellulose Fiber 11] Even when using anion-modified cellulose fiber 11 into which phosphoric acid is introduced instead of anion-modified cellulose fiber 1 into which a carboxy group is introduced, a resin composition similar to that of Examples 1 to 16 can be obtained. Such anion-modified cellulose fiber 11 can be prepared by the following phosphorylation treatment.

[0254] [Phosphorylation Treatment] To 100 parts by mass of the solid content of softwood bleached kraft pulp fiber as the raw material natural cellulose fiber, an aqueous mixed solution of ammonium dihydrogen phosphate and urea is impregnated, and it is squeezed so as to be 56 parts by mass of ammonium dihydrogen phosphate and 150 parts by mass of urea to obtain chemically impregnated fiber.

[0255] The chemical solution-impregnated fibers are dried in a dryer at 105°C to evaporate the moisture. The fibers from which the moisture has been evaporated are heated in a hot air dryer set at 140°C for 4 minutes. To 100 parts by mass of the resulting fibers, 10,000 parts by mass of deionized water is added, and after stirring to disperse the fibers, the solid content is filtered off by suction filtration. To 100 parts by mass of the solid content in the filtered cake, 10,000 parts by mass of deionized water is added, and after stirring to disperse the fibers, the solid content is filtered off by suction filtration.

[0256] To the resulting cake, 10,000 parts by mass of deionized water is added, and while stirring, a 1N aqueous sodium hydroxide solution is dropped in to obtain a slurry with a pH of 12 - 13. Then, while stirring, 0.01M hydrochloric acid is added thereto to adjust the pH of the suspension to 2. Then, the solid content is filtered off by suction filtration. The operation of dispersing the resulting cake in deionized water and filtering off the cake by suction filtration is repeated until the conductivity of the filtrate becomes 200 μS / cm or less. The resulting solid content is dehydrated to obtain an anion-modified cellulose fiber 11.

Industrial Applicability

[0257] The resin composition of the present invention can be used as a structural adhesive for vehicle assembly parts and the like.

Claims

1. A resin composition comprising (A) modified cellulose fibers, (B) a urethane-modified epoxy resin, and (C) an epoxy resin other than the urethane-modified epoxy resin.

2. The composition according to claim 1, wherein (A) the modified cellulose fibers have a cellulose type I crystal structure and an average fiber diameter of 1 nm or more and 300 nm or less.

3. The composition according to claim 1, wherein (A) the modified cellulose fibers are those in which a modifying group is bonded to an anion-modified cellulose fiber, and the modifying group contains at least one selected from the group consisting of (i) a hydrocarbon group having 3 or more carbon atoms, (ii) a silicone chain, and (iii) an alkylene oxide chain.

4. The composition according to claim 3, wherein the modifying group and the anionic group of the anion-modified cellulose fiber are bonded via an ionic bond and / or a covalent bond.

5. The composition according to claim 1, wherein the epoxy resin other than (C) the urethane-modified epoxy resin is at least one selected from the group consisting of bisphenol type epoxy resins, rubber-modified epoxy resins, alicyclic epoxy resins, glycidylamine type epoxy resins, polysulfide-modified epoxy resins, chelate-modified epoxy resins, trisphenol methane type epoxy resins, naphthalene type epoxy resins, dicyclopentadiene-modified epoxy resins, epoxidized products of aliphatic polyols or their derivatives, polyether-modified epoxy resins, polyfunctional aromatic epoxy resins, and hydrogenated bisphenol type epoxy resins.

6. The composition according to claim 1, wherein the content of (B) the urethane-modified epoxy resin in the composition is 1% by mass or more and less than 80% by mass, and the content of (C) the epoxy resin other than the urethane-modified epoxy resin is 1% by mass or more and less than 80% by mass.

7. The composition according to claim 1, obtained by mixing a mixture of (A) modified cellulose fibers and (B) a urethane-modified epoxy resin with (C) an epoxy resin other than the urethane-modified epoxy resin.

8. The composition according to claim 1, obtained by mixing a mixture of (B) a urethane-modified epoxy resin and (C) an epoxy resin other than the urethane-modified epoxy resin with (A) modified cellulose fibers.

9. The composition according to claim 1, obtained by mixing a mixture of (A) modified cellulose fibers and (C) an epoxy resin other than the urethane-modified epoxy resin with (B) a urethane-modified epoxy resin.

10. An adhesive comprising the composition according to any one of Claims 1 to 9.

11. The adhesive according to Claim 10, wherein the adhesive is a structural adhesive.

12. (A) The adhesive according to Claim 10, further comprising a filler other than the modified cellulose fiber.

13. The adhesive according to Claim 10, which is used for adhering vehicle assembly parts.

14. A method for adhering vehicle assembly parts, comprising a step of adhering vehicle assembly parts using the adhesive according to Claim 10.

15. (B) In a method for producing a resin composition containing a urethane-modified epoxy resin and (C) an epoxy resin other than the urethane-modified epoxy resin, Step 1: A step of mixing (A) a modified cellulose fiber and (B) a urethane-modified epoxy resin, and Step 2: A step of mixing the mixture obtained in Step 1 with (C) an epoxy resin other than the urethane-modified epoxy resin A method for producing a resin composition having.

16. (B) In a method for producing a resin composition containing a urethane-modified epoxy resin and (C) an epoxy resin other than the urethane-modified epoxy resin, a production method having the following Step 3 or Step 4. Step 3: A step of mixing (A) a modified cellulose fiber, (B) a urethane-modified epoxy resin, and (C) an epoxy resin other than the urethane-modified epoxy resin Step 4: A step of mixing (B) a urethane-modified epoxy resin and (C) an epoxy resin other than the urethane-modified epoxy resin (Step 4-1), and mixing the obtained composition with (A) a modified cellulose fiber (Step 4-2)

17. (B) In a method for producing a resin composition containing a urethane-modified epoxy resin and (C) an epoxy resin other than the urethane-modified epoxy resin, Step 5: A step of mixing (A) a modified cellulose fiber and (C) an epoxy resin other than the urethane-modified epoxy resin Step 6: A step of mixing the composition obtained in Step 5 with (B) a urethane-modified epoxy resin A method for producing a resin composition having.

18. (A) A method for improving the elongation at break of a structural adhesive, comprising a step of mixing a modified cellulose fiber and (B) a urethane-modified epoxy resin.

19. An adhesive kit comprising a container containing the adhesive according to Claim 10.

20. A first container containing the composition according to any one of Claims 1 to 9, A second container containing a curing agent An adhesive kit comprising.

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