JP2018178309A - Cellulose fiber composite - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cellulose fiber composite that has an excellent feeling when forming a film, and causes no stickiness.SOLUTION: The present invention provides a cellulose fiber composite in which: at least one selected from a carboxy group and a hydroxy group, of a cellulose fiber with a carboxy group content of 0.1 mmol/g or more, has a silicone compound bonded thereto, as a modifying group.SELECTED DRAWING: None

Description

  The present invention relates to cellulose fiber composites.

  Conventionally, cellulose nanofibers having a carboxy group have been developed using a TEMPO catalyst, but in order to enable the development of application to various applications, for example, a straight chain via the amino group in the carboxyl group A modified cellulose nanofiber has been proposed in which linear or branched molecules are bound (Patent Document 1).

International Publication No. 2013/077354

  As an application of such a modification, use as a material of a membrane can be considered. However, it has been found that simply applying the technology of Patent Document 1 can not necessarily satisfy the user in terms of the feel and stickiness of the formed film.

  The present invention relates to a cellulose fiber composite which is excellent in feel when a film is formed, and which is not sticky.

The present invention relates to the following [1].
[1] A cellulose fiber composite in which a silicone compound is bonded as a modifying group to at least one selected from the carboxy group and hydroxyl group of cellulose fiber having a carboxy group content of 0.1 mmol / g or more.

  The cellulose fiber composite of the present invention is excellent in feel when forming a film, and can exert the effect that no stickiness occurs.

[Cellulose fiber complex]
The cellulose fiber composite of the present invention is obtained by bonding a silicone compound as a modifying group to at least one selected from the carboxy group and hydroxyl group of cellulose fiber having a carboxy group content of 0.1 mmol / g or more.

  When the cellulose fiber composite of the present invention is in the form of a gel membrane (simply referred to as "membrane") swollen with an organic medium, the feel of the membrane is good and there is no stickiness. Although the mechanism which exhibits this effect is not clear, as a result of forming a uniform network of the cellulose fiber, it can be presumed to be because the organic medium was firmly held.

(Cellulose fiber)
As the cellulose fiber of the raw material, natural cellulose fiber is preferable from the environmental point of view. For example, wood pulp such as softwood pulp and hardwood pulp; cotton pulp such as cotton linter and cotton lint; non-wood pulp such as straw pulp and bagasse pulp Base pulp; bacterial cellulose etc. may be mentioned, and one of these may be used alone or in combination of two or more.
The cellulose fiber used in the present invention is a cellulose fiber having a predetermined amount of carboxy groups (hereinafter also referred to as oxidized cellulose fiber), and can be obtained by oxidizing the cellulose fiber.

(Oxidized cellulose fiber)
Oxidized cellulose fiber uses, for example, 2,2,6,6-tetramethyl-1-piperidine-N-oxyl (TEMPO) as a catalyst, and an oxidizing agent such as sodium hypochlorite, sodium bromide, etc. It is possible to apply the method of oxidation using bromide in combination. In more detail, the method of Unexamined-Japanese-Patent No. 2011-140632 can be referred, Furthermore, by performing an additional oxidation process or a reduction process, it can prepare as an oxidized cellulose fiber which removed the aldehyde.

By oxidizing cellulose fibers using TEMPO as a catalyst, the C6-position group (-CH ₂ OH) of the cellulose structural unit is selectively converted to a carboxy group. Therefore, as a preferable aspect of the cellulose fiber whose carboxy group is 0.1 mmol / g or more in this invention, the cellulose fiber whose C6 position of a cellulose structural unit is a carboxy group is mentioned.

(Carboxyl group content)
The cellulose fiber constituting the cellulose fiber composite of the present invention has a carboxy group content of 0.1 mmol / g or more, preferably 0.4 mmol / g or more, from the viewpoint of stable refinement and introduction of a modifying group. More preferably, it is 0.6 mmol / g or more, further preferably 0.8 mmol / g or more. Also, from the viewpoint of improving the handleability, it is preferably 3 mmol / g or less, more preferably 2 mmol / g or less, and still more preferably 1.8 mmol / g or less. In addition, "carboxy group content" means the total amount of the carboxy group in the cellulose which comprises a cellulose fiber, and, specifically, it measures by the method as described in the below-mentioned Example.

  Further, the preferable ranges of the average fiber diameter, average fiber length and average aspect ratio of the cellulose fiber and the oxidized cellulose fiber are the same as those of the below-mentioned cellulose fiber composite, and the same measuring methods as those of the below-mentioned cellulose fiber composite It can be determined by

<Modification group>
The cellulose fiber composite of the present invention is, for example, preferably one or more selected from the group consisting of the carboxy group and the hydroxyl group of the above-mentioned oxidized cellulose fiber, preferably the carboxy group, and the silicone compound as the modifying group. It is obtained by combining. The manner of bonding to a carboxy group includes ionic bonding and covalent bonding. Examples of the covalent bond here include an amide bond, an ester bond, and a urethane bond. Among them, an amide bond is preferable from the viewpoint of obtaining a film with good feel and no stickiness. Further, the manner of bonding to a hydroxyl group includes a covalent bond, and specifically, an ester bond; an ether bond such as carboxymethylation and carboxyethylation; and a urethane bond. The cellulose fiber composite of the present invention is obtained by ionically bonding and / or amide bonding a silicone compound to a carboxy group already present on the surface of a cellulose fiber, from the viewpoint of obtaining a film with good feel and no stickiness. Is preferred.

(Silicone compound)
The silicone compounds can be commercially available products or can be prepared according to known methods.

  The silicone compound used in the present invention includes amino-modified silicone, epoxy-modified silicone, carboxy-modified silicone, carbinol-modified silicone and the like, and the position of the reactive group may be the side chain or end of the silicone compound. Among these, from the viewpoint of obtaining a film with good feel and no stickiness, it is preferably an amino-modified silicone.

(Amino-modified silicone compound)
Preferred amino-modified silicone compounds are amino-modified silicone compounds having a kinematic viscosity of 10 to 20,000 mm ² / s at 25 ° C. and an amino equivalent weight of 400 to 8,000 g / mol.

The kinematic viscosity at 25 ° C. can be determined with an Ostwald viscometer, and from the viewpoint of obtaining a film with good feel and no stickiness, more preferably 200 to 10,000 mm ² / s, still more preferably 500 to 5, It is 000 mm ² / s.

  The amino equivalent is preferably 400 to 8,000 g / mol, more preferably 600 to 5,000 g / mol, and still more preferably 800 to 3,000 g / mol from the viewpoint of obtaining a film with good feel and no stickiness. It is mol. The amino equivalent is a molecular weight per nitrogen atom, and is determined by amino equivalent (g / mol) = mass average molecular weight / number of nitrogen atoms per molecule. Here, the mass average molecular weight is a value determined by gel permeation chromatography using polystyrene as a standard substance, and the number of nitrogen atoms can be determined by elemental analysis.

  As a specific example of the amino-modified silicone compound, a compound represented by general formula (a1) can be mentioned.

[Wherein, R ^1a represents a group selected from an alkyl group having 1 to 3 carbon atoms, a hydroxy group, an alkoxy group having 1 to 3 carbon atoms, or a hydrogen atom, and from the viewpoint of obtaining a film with good feel and no stickiness Preferably a methyl group or a hydroxy group. R ^2a is a group selected from an alkyl group having 1 to 3 carbon atoms, a hydroxy group or a hydrogen atom, and is preferably a methyl group or a hydroxy group from the viewpoint of obtaining a film with good feel and no stickiness. B represents a side chain having at least one amino group, and R ^3a represents an alkyl group having 1 to 3 carbon atoms or a hydrogen atom. Each of x and y represents an average degree of polymerization, and is selected so that the kinematic viscosity at 25 ° C. and the amino equivalent of the compound fall within the above range. R ^1a , R ^2a and R ^3a may be the same or different, and a plurality of R ^2a may be the same or different. ]

  In the compound of the general formula (a1), x is preferably a number of 10 to 10,000, more preferably a number of 20 to 5,000, still more preferably 30 from the viewpoint of obtaining a film with good feel and no stickiness. It is a number of ~ 3,000. y is preferably a number of 1 to 1,000, more preferably a number of 1 to 500, still more preferably a number of 1 to 200. The weight average molecular weight of the compound of the general formula (a1) is preferably 2,000 to 1,000,000, more preferably 5,000 to 100,000, and still more preferably 8,000 to 50,000.

In the general formula (a1), examples of the side chain B having an amino group include the following.
-C ₃ H ₆ -NH _{2
-C 3 H 6 -NH-C 2} H 4 -NH 2
_{-C 3 H 6 -NH- [C 2} H 4 -NH] e -C 2 H 4 -NH 2
_{-C 3 H 6 -NH (CH 3} )
_{-C 3 H 6 -NH-C 2} H 4 -NH (CH 3)
_{-C 3 H 6 -NH- [C 2} H 4 -NH] f -C 2 H 4 -NH (CH 3)
_{-C 3 H 6 -N (CH 3} ) 2
_{-C 3 H 6 -N (CH 3} ) -C 2 H 4 -N (CH 3) 2
_{-C 3 H 6 -N (CH 3} ) - [C 2 H 4 -N (CH 3)] g -C 2 H 4 -N (CH 3) 2
_{-C 3 H 6 -NH-cyclo-} C 5 H 11
(Here, e, f and g are each a number of 1 to 30.)

The amino-modified silicone compound used in the present invention is, for example, a hydrolyzate obtained by hydrolyzing an organoalkoxysilane represented by the general formula (a2) with an excess of water, and sodium hydroxide with dimethylcyclopolysiloxane. The reaction is equilibrated by heating to 80 to 110 ° C. using a basic catalyst such as, and produced by neutralizing the basic catalyst using an acid when the reaction mixture reaches a desired viscosity (See JP-A-53-98499).
_{H 2 N (CH 2) 2} NH (CH 2) 3 Si (CH 3) (OCH 3) 2 (a2)

Moreover, as an amino-modified silicone compound, from the viewpoint of obtaining a film with good feel and no stickiness, preferably, one monoamino-modified silicone having one amino group in one side chain B and one side chain B And at least one compound selected from the group consisting of diamino-modified silicones having two amino groups, and more preferably a compound in which the side chain B having an amino group is represented by —C ₃ H ₆ —NH ₂ [ , (a1-1) a compound in which the side chain B is represented by _{-C 3 H 6 -NH-C 2} H 4 -NH 2 with components that] and an amino group [hereinafter, the (a1-2) as component] At least one selected from the group consisting of

As the amino-modified silicone compound in the present invention, from the point of performance, TSF 4703 (kinematic viscosity: 1000, amino equivalent: 1600), TSF 4708 (kinematic viscosity: 1000, amino equivalent: 2800) manufactured by Momentive Performance Materials, Inc. Toray Dow Corning Silicone Co., Ltd. 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), BY 16-898 (Kinematic viscosity: 2000, Amino equivalent: 2900), FZ-3760 (Kinematic viscosity: 220, amino equivalent: 1 00), Shin-Etsu Chemical Co., Ltd. KF 8002 (Kinematic viscosity: 1100, Amino equivalent: 1700), KF 867 (Kinematic viscosity: 1300, Amino equivalent: 1700), KF-864 (Kinematic viscosity: 1700, Amino equivalent: 3800) ), BY16-213 (kinetic viscosity: 55, amino equivalent: 2700), BY16-853U (kinetic viscosity: 14, amino equivalent: 450) are preferable. In (), the kinematic viscosity shows a measured value at 25 ° C. (unit: mm ² / s), and the unit of amino equivalent is g / mol.

As component (a1-1), BY16-213 (kinetic viscosity: 55, amino equivalent: 2700) and BY16-853U (kinetic viscosity: 14, amino equivalent: 450) are more preferable.
As component (a1-2), SF8417 (kinetic viscosity: 1200, amino equivalent: 1700), BY16-209 (kinetic viscosity: 500, amino equivalent: 1800), FZ-3760 (kinetic viscosity: 220, amino equivalent: 1600) Is more preferred.

  The average bonding amount of the modifying group in the cellulose fiber composite, ie, the silicone group, is preferably 0.01 mmol / g or more, more preferably 0.05 mmol / g or more, from the viewpoint of obtaining a film with good feel and no stickiness. More preferably, it is 0.1 mmol / g or more, more preferably 0.3 mmol / g or more, further preferably 0.5 mmol / g or more. Further, from the viewpoint of reactivity, it is preferably 3 mmol / g or less, more preferably 2.5 mmol / g or less, still more preferably 2 mmol / g or less, still more preferably 1.8 mmol / g or less, still more preferably 1.5 mmol / g. g or less.

  Further, the introduction rate of the silicone group is preferably 10% or more, more preferably 30% or more, further preferably 50% or more, still more preferably 60% or more, from the viewpoint of obtaining a film with good feel and no stickiness. It is more preferably 70% or more, and from the viewpoint of reactivity, preferably 99% or less, more preferably 97% or less, still more preferably 95% or less, still more preferably 90% or less.

  The modifying group may have a substituent. As a substituent, for example, a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, an isobutoxy group, a sec-butoxy group, a tert-butoxy group, a pentyloxy group, an isopentyloxy group, a hexyloxy group, etc. Alkoxy group having 1 to 6 carbon atoms; methoxycarbonyl group, ethoxycarbonyl group, propoxycarbonyl group, isopropoxycarbonyl group, butoxycarbonyl group, isobutoxycarbonyl group, sec-butoxycarbonyl group, tert-butoxycarbonyl group, pentyloxycarbonyl group Group, alkoxy group such as isopentyloxycarbonyl group, alkoxy group having 1 to 6 carbon atoms; halogen atom such as fluorine atom, chlorine atom, bromine atom, iodine atom; carbon number 1 such as acetyl group, propionyl group ~ 6 Sill group; an aralkyl group; an aralkyloxy group; an alkylamino group having 1 to 6 carbon atoms; the carbon number of the alkyl group have dialkylamino group having 1 to 6.

  In the present specification, the average bonding amount of the modifying group can be adjusted by the addition amount of the silicone compound, the type of the silicone compound, the reaction temperature, the reaction time, the solvent and the like. Further, the average bonding amount (mmol / g) and introduction ratio (%) of the modifying group in the cellulose fiber composite are the amount and ratio of the modifying group introduced to the carboxy group or hydroxyl group of the cellulose fiber surface, The carboxyl group content and the hydroxyl group content of the cellulose fiber can be calculated by measuring according to a known method (for example, titration, IR measurement, etc.).

<Production Method of Cellulose Fiber Complex>
The cellulose fiber composite of the present invention can be produced according to a known method without particular limitation as long as a modifying group can be introduced into the above-mentioned oxidized cellulose fiber. In addition, about the oxidized cellulose fiber here, a carboxy group is 0.1 mmol / g or more, preferably 0.2 mmol / g by referring to a well-known method, for example, the method of Unexamined-Japanese-Patent No. 2011-140632. An oxidized cellulose fiber containing at least g, more preferably at least 0.4 mmol / g can be prepared. The carboxy group content of the oxidized cellulose fiber can be determined by the same measurement method as that of the cellulose fiber composite described later.

As a specific manufacturing method, the following two modes can be mentioned depending on the mode of introduction of the modifying group into the oxidized cellulose fiber. That is, an embodiment in which the modifying group is bound to the oxidized cellulose fiber by ionic bond (embodiment A), and an embodiment in which the modifying group is bound to the oxidized cellulose fiber by covalent bond (embodiment B) can be mentioned. In addition, as a covalent bond, the case of an amide bond is shown below.
Aspect A
Step (1): Step of obtaining oxidized cellulose fiber by oxidizing natural cellulose fiber with co-oxidant in the presence of N-oxyl compound Step (2A): oxidized cellulose fiber obtained in step (1) Process of mixing with silicone compound [aspect B]
Step (1): Step of obtaining oxidized cellulose fiber by oxidizing natural cellulose fiber with co-oxidant in the presence of N-oxyl compound Step (2B): oxidized cellulose fiber obtained in step (1) and Process of amidation reaction with silicone compound

  The method for introducing a modifying group can be carried out, for example, with reference to the method described in JP-A-2015-143336 for the embodiment A and the method described in JP-A-2015-143337 for the embodiment B. In the present invention, a method (first production mode) of performing the step (2A or 2B) after the step (1) is performed after the step (1) to make the fine oxidized cellulose fiber, and the step (step 1) The method (2nd manufacturing form) which performs a process (2A or 2B) after 1), and performs a refinement | miniaturization process after that and obtains a fine cellulose fiber composite is mentioned. In addition, the cellulose fiber after a refinement | miniaturization process may be called "fine cellulose fiber", and the oxidized cellulose fiber after a refinement | miniaturization process may be called "finely oxidized cellulose fiber" especially.

  Hereinafter, based on the first production mode of aspect A, a method for producing a cellulose fiber composite will be described.

[Step (1)]
Step (1) is a step of oxidizing natural cellulose fiber with a co-oxidant in the presence of an N-oxyl compound to obtain oxidized cellulose fiber. Specifically, for natural cellulose fibers, an oxidation treatment process (for example, 2,2,6,6 tetramethylpiperidine-1-oxyl (described in JP-A-2015-143336 or JP-A-2015-143337) Oxidized cellulose fiber having a carboxy group content of preferably 0.1 mmol / g or more is obtained by performing oxidation treatment (as TEMPO) and purification step (if necessary). In addition, sodium bromide, sodium hypochlorite etc. are mentioned as a co-oxidant said here.

(Micronization process)
Next, in the first production mode, a step of miniaturizing the oxidized cellulose fiber obtained in the step (1) (after the optional purification step) is performed to obtain a fine oxidized cellulose fiber. In the refining step, it is preferable to disperse the oxidized cellulose fiber which has been subjected to the refining step in a solvent to carry out a refining treatment.

  The solvent as the dispersion medium is, besides water, an alcohol having 1 to 6 carbon atoms such as methanol, ethanol or propanol, preferably 1 to 3 carbon atoms; ketones having 3 to 6 carbon atoms such as acetone, methyl ethyl ketone or methyl isobutyl ketone Linear or branched saturated hydrocarbon having 1 to 6 carbon atoms or unsaturated hydrocarbon; aromatic hydrocarbon such as benzene and toluene; halogenated hydrocarbon such as methylene chloride and chloroform; lower hydrocarbon having 2 to 5 carbon atoms Examples thereof include polar solvents such as alkyl ether; N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide, diesters of succinic acid and triethylene glycol monomethyl ether, and the like. These can be used alone or in combination of two or more, but from the viewpoint of the operability of the refining treatment, water, alcohols having 1 to 6 carbon atoms, ketones having 3 to 6 carbon atoms, and 2 carbon atoms And polar solvents such as N, N-dimethylformamide, N, N-dimethylacetamide, dimethylsulfoxide, methyl triglycol diester succinate, etc. are preferable, and water is more preferable from the viewpoint of environmental load reduction. The amount of the solvent used is not particularly limited as long as it is an effective amount capable of dispersing the oxidized cellulose fiber, but is preferably 1 to 500 times by mass, more preferably 2 to 200 times by mass to the oxidized cellulose fiber Is more preferred.

  A well-known disperser is suitably used as an apparatus used by refinement | miniaturization processing. For example, a disintegrator, a disintegrator, a low pressure homogenizer, a high pressure homogenizer, a grinder, a cutter mill, a ball mill, a jet mill, a short screw extruder, a twin screw extruder, an ultrasonic stirrer, a household juicer mixer and the like can be used. Moreover, as for solid content concentration of the reactant fiber in refinement processing, 50 mass% or less is preferable.

  Thus, the hydroxyl group at the C6 position of the cellulose constitutional unit is selectively oxidized to a carboxy group via an aldehyde group, and it is composed of cellulose having a carboxy group content of 0.1 mmol / g or more, preferably an average fiber diameter of 0. It is possible to obtain a finely divided oxidized cellulose fiber of 1 to 200 nm.

[Step (2A)]
In the first production mode, the step (2A) is a step of mixing the fine oxidized cellulose fiber obtained through the above-mentioned refining step and the silicone compound to obtain a fine cellulose fiber composite. Specifically, the finely oxidized cellulose fiber and the silicone compound may be mixed in a solvent, and for example, they can be produced according to the method described in JP-A-2015-143336.

  Examples of the silicone compound used in the step (2A) include those described above.

  The use amount of the silicone compound can be determined by the desired bonding amount of the modifying group in the cellulose fiber composite, but from the viewpoint of reactivity, the amine group is preferably to 1 mol of carboxy group contained in the oxidized cellulose fiber. Is preferably 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, and preferably 50 mol or less from the viewpoint of product purity The amount is preferably 20 mol or less, more preferably 10 mol or less. In addition, the compound of the quantity contained in the said range may be provided to reaction at once, or may be divided and provided to reaction. When the compound is a monoamine, the above-mentioned amine group is the same as the amine.

  As the solvent, it is preferable to select a solvent in which the compound to be used dissolves, for example, ethanol, isopropyl alcohol (IPA), N, N-dimethylformamide (DMF), dimethylsulfoxide (DMSO), N, N-dimethylacetamide, Tetrahydrofuran (THF), a diester of succinic acid and triethylene glycol monomethyl ether, acetone, methyl ethyl ketone (MEK), acetonitrile, dichloromethane, chloroform, toluene, acetic acid, water and the like can be mentioned, and one or two of these may be used. The above can be used in combination. Among these polar solvents, diesters of succinic acid and triethylene glycol monomethyl ether, ethanol, IPA, DMF and water are preferable.

  The temperature at the time of mixing is preferably 0 ° C. or more, more preferably 5 ° C. or more, still more preferably 10 ° C. or more from the viewpoint of the reactivity of the compound. Further, from the viewpoint of product quality such as coloring, it is preferably 50 ° C. or less, more preferably 40 ° C. or less, and still more preferably 30 ° C. or less. The mixing time can be appropriately set according to the type of compound and solvent used, but from the viewpoint of the reactivity of the compound, it is preferably 0.01 hour or more, more preferably 0.1 hour or more, and still more preferably 1 It is time or more, preferably 48 hours or less, more preferably 24 hours or less.

  After completion of the reaction, post treatment may be appropriately performed to remove unreacted compounds and the like. As a method of the post-treatment, for example, filtration, centrifugation, dialysis and the like can be used.

  Moreover, about the manufacturing method of aspect B, since a process (1) can be performed similarly to the aspect A, it describes about the process (2B) in a 1st manufacture form below. Moreover, it can manufacture by the method of Unexamined-Japanese-Patent No. 2013-151661, for example.

[Step (2B)]
In the first production mode, the step (2B) is a step of obtaining a fine cellulose fiber composite by subjecting the fine oxidized cellulose fiber obtained through the above-mentioned fineness step to the amidization reaction with the silicone compound. The mixing method is not particularly limited as long as the raw materials react with each other. Specifically, the raw materials are mixed in the presence of a condensing agent, and the carboxy group and the silicone compound contained in the finely oxidized cellulose fiber Condensation reaction with an amino group of to form an amide bond.

  As a silicone compound used at a process (2B), the above-mentioned thing is mentioned.

  In step (2B), the finely oxidized cellulose fiber and the silicone compound are amidated in the presence of a condensing agent.

  The amount of the silicone compound used is preferably 0.1 mol or more, more preferably 0.5 mol or more, based on 1 mol of carboxy group contained in the finely oxidized cellulose fiber, from the viewpoint of reactivity. From the viewpoint of purity, the amount is preferably 50 mol or less, more preferably 20 mol or less, and still more preferably 10 mol or less. In addition, the compound of the quantity contained in the said range may be provided to reaction at once, or may be divided and provided to reaction.

  The condensing agent is not particularly limited, and examples thereof include condensing agents described in Synthetic Chemical Series Peptide Synthesis (Maruzen Co.) P116 or Tetrahedron, 57, 1551 (2001), and the like, 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.

  In the above-mentioned amidation reaction, the solvent in the above-mentioned refinement process is mentioned, and it is preferred to choose the solvent in which the compound to be used dissolves.

  The reaction time and reaction temperature in the amidation reaction can be appropriately selected according to the type of compound and solvent used, etc., but from the viewpoint of reaction rate, preferably 1 to 24 hours, more preferably 10 to 20 hours It is. The reaction temperature is preferably 0 ° C. or more, more preferably 5 ° C. or more, still more preferably 10 ° C. or more from the viewpoint of reactivity. Further, from the viewpoint of product quality such as coloring, it is preferably 200 ° C. or less, more preferably 80 ° C. or less, and still more preferably 30 ° C. or less.

  After the reaction, post-treatment may be appropriately performed to remove unreacted compounds, condensing agents and the like. As a method of the post-treatment, for example, filtration, centrifugation, dialysis and the like can be used.

  In any of the embodiment A and the embodiment B, in the second production mode, each step described above is performed in the order of step (1), step (2A) or step (2B), and refinement step. , And in the same manner as in the first embodiment.

  Further, it may be a fine cellulose fiber composite obtained by combining aspect A and aspect B, that is, a fine cellulose fiber composite having a modifying group linked via an ionic bond and a modifying group linked via an amide bond. It may be the body. In this case, either step (2A) or step (2B) may be performed first.

  Thus, it is possible to obtain a fine cellulose fiber composite in which a silicone compound (silicone group) as a modifying group is linked to oxidized cellulose fiber via ionic bond and / or covalent bond.

  The average fiber diameter of the obtained fine cellulose fiber composite is preferably 0.1 nm or more, more preferably 0.5 nm or more, still more preferably 1 nm or more, from the viewpoint of obtaining a film with good feel and no stickiness. Preferably it is 2 nm or more, More preferably, it is 3 nm or more. From the same point of view, it is preferably 200 nm or less, more preferably 100 nm or less, still more preferably 50 nm or less, still more preferably 20 nm or less, still more preferably 10 nm or less, more preferably 6 nm or less, more preferably 5 nm or less.

  The length (average fiber length) of the obtained fine cellulose fiber composite is preferably 150 nm or more, more preferably 200 nm or more, from the viewpoint of obtaining a film with good feel and no stickiness. In addition, from the same viewpoint, it is preferably 1000 nm or less, more preferably 750 nm or less, still more preferably 500 nm or less, and further preferably 400 nm or less.

  In the present invention, the average fiber diameter and the average fiber length of the fine cellulose fiber composite are not limited to the above ranges, and may be, for example, on the order of micrometers.

  The average aspect ratio (fiber length / fiber diameter) of the obtained fine cellulose fiber composite is preferably 1 or more, more preferably 10 or more, still more preferably from the viewpoint of obtaining a film with good feel and no stickiness. Is 20 or more, more preferably 40 or more, still more preferably 50 or more, and from the same viewpoint, preferably 150 or less, more preferably 140 or less, still more preferably 130 or less, still more preferably 100 or less, more preferably 95 The following is more preferably 90 or less. When the average aspect ratio is in the above range, the standard deviation of the aspect ratio is preferably 60 or less, more preferably 50 or less, still more preferably 45 from the viewpoint of obtaining a film with good feel and no stickiness. The lower limit is not particularly set, but is preferably 4 or more from the viewpoint of economy.

  The obtained cellulose fiber composite can be used in the state of a dispersion after the above-mentioned post-treatment, or it can be used as a dry powdered cellulose by removing the solvent from the dispersion by a drying treatment or the like. A fiber composite can also be obtained and used. Here, the “powder form” is a powder form in which the cellulose fiber complex is aggregated, and does not mean cellulose particles.

  As a powdery cellulose fiber composite, for example, a dried product obtained by drying the dispersion of the cellulose fiber composite as it is; a product obtained by powderizing the dried product by mechanical processing; a known dispersion of the cellulose fiber composite And the powder obtained by the spray drying method of the present invention; and those obtained by powderizing the dispersion of the cellulose fiber composite by the known freeze drying method. The spray drying method is a method in which the dispersion of the cellulose fiber composite is sprayed in the air and dried.

[film]
A membrane can be produced by swelling the cellulose fiber composite of the present invention with an organic medium. That is, such a membrane comprises the cellulose fiber composite of the present invention and an organic medium. Such a film can be used as a material of a container in the field of food and cosmetics and the like.

  The content of the cellulose fiber composite of the present invention in the membrane is preferably 2% by mass or more, more preferably 3% by mass or more, and still more preferably 4% by mass or more, from the viewpoint of feel and stickiness of the membrane. Moreover, from the same viewpoint, the content is preferably 20% by mass or less, more preferably 18% by mass or less, and still more preferably 17% by mass or less.

<Organic medium>
The organic medium used in the present invention may be hydrophilic or hydrophobic, but is preferably an organic medium having an SP value of 5 or more and 25 or less from the viewpoint of obtaining a film with good feel and no stickiness.

The SP value in the present specification indicates the solubility parameter (unit: (cal / cm ³ ) ^1/2 ) calculated by the Fedors method, and, for example, the reference document “SP value basic / application and calculation method” (information mechanism (2005), Polymer handbook Third edition (A Wiley-Interscience publication, 1989), and the like.

  The mass average molecular weight of the organic medium having an SP value of 5 or more and 25 or less used in the present invention is not particularly limited, but is preferably 50 or more, more preferably 100 or more, and preferably 100,000 or less More preferably, it is 50,000 or less, More preferably, it is 20,000 or less.

  Examples of hydrophobic organic media used in the present invention include organic media having an SP value of 5 or more and less than 10, such as oleic acid (SP value: 9.2), D-limonene (SP value: 9) .4), polyethylene glycols (PEG 400 (SP value: 9.4), etc.), dimethyl succinate (SP value: 9.9), neopentyl glycol dicaprate (SP value: 8.9), hexyl laurate SP value: 8.6), isopropyl laurate (SP value 8.5), isopropyl myristate (SP value 8.5), isopropyl palmitate (SP value 8.5), isopropyl oleate (SP value: 8. 6), hexadecane (SP value: 8.0), olive oil (SP value: 9.3), jojoba oil (SP value: 8.6), squalane (SP value: 7.9), liquid paraffin (SP value: 7.9 Fluorocarbons (Fluorinert FC-40 (manufactured by 3M, SP value: 6.1), Florinert FC-43 (manufactured by 3M, SP value: 6.1), Florinert FC-72 (manufactured by 3M, SP value: 6.1), Fluorinert FC-770 (manufactured by 3M, SP value: 6.1), silicone oils (KF-96-1cs (manufactured by Shin-Etsu Chemical Co., SP value: 7.3), KF-96 -10 cs (Shin-Etsu Chemical Co., Ltd., SP value: 7.3), KF-96-50 cs (Shin-Etsu Chemical Co., Ltd., SP value: 7.3), KF-96-100 cs (Shin-Etsu Chemical Co., Ltd., SP value: 7) .3), KF-96-1000cs (manufactured by Shin-Etsu Chemical Co., Ltd., SP value: 7.3), and the like. Among these, the SP value of the organic medium is preferably 9.5 or less, preferably 5 or more, more preferably 6 or more, from the viewpoint of obtaining a film with good feel and no stickiness, for example, These include squalane, the above-mentioned polyethylene glycols, and the above-mentioned silicone oils.

  Moreover, as a hydrophilic organic medium used by this invention, SP value is 10 or more and 25 or less organic medium is mentioned, For example, ethylene glycol (SP value: 14.6), propylene glycol (SP value: 12.6), propylene glycol monomethyl ether (SP value: 10.1), diethylene glycol (SP value: 12.1), diethylene glycol monobutyl ether (SP value: 10.2), dimethyl sulfoxide (SP value: 14.5) Dimethylformamide (SP value: 12.1), dimethylacetamide (SP value: 10.8), ethylene carbonate (SP value: 14.7), propylene-1,2-carbonate (SP value: 13.3), Heptanol (SP value: 10.6), 2-butanol (SP value: 10.8), 1,4-butanediol ( P value: 12.1), acetonitrile (SP value: 11.9), butanoic acid (SP value: 10.5), cresol (SP value: 10.2), acetophenone (SP value: 10.6), benzyl Alcohol (SP value: 12.1), glycerin (SP value: 16.5), etc. may be mentioned. Among them, the SP value of the organic medium is preferably 20 or less, more preferably 18 or less, and still more preferably 17 or less, from the viewpoint of obtaining a film with good feel and no stickiness, for example ethylene glycol, Propylene glycol, propylene glycol monomethyl ether, diethylene glycol, diethylene glycol monobutyl ether, glycerin are mentioned.

  The content of the organic medium in the film is preferably 80% by mass or more, more preferably 82% by mass or more, and still more preferably 83% by mass or more from the viewpoint of feel and stickiness of the film. In addition, from the same viewpoint, the content is preferably 98% by mass or less, more preferably 97% by mass or less, and still more preferably 96% by mass or less.

[Method of producing membrane]
The method for producing a membrane includes, for example, Step 1 of preparing a dispersion containing the cellulose fiber composite of the present invention and an organic medium, and Step 2 of applying the dispersion prepared in Step 1 to a molded article. The method is mentioned.

<Step 1>
A dispersion containing the cellulose fiber composite of the present invention and an organic medium can be prepared by mixing these components with a solvent.

  Examples of the solvent include isopropyl alcohol, ethanol, methyl ethyl ketone, toluene, ethyl acetate, cyclohexane and the like.

  As mixing conditions of these components, 15-35 degreeC is preferable, for example. Furthermore, as a mixing time, 10 to 60 minutes are preferable.

  The mixing ratio of the cellulose fiber composite of the present invention to the organic medium is preferably, for example, a mass ratio of cellulose fiber to organic medium in the cellulose fiber composite from the viewpoint of obtaining a film with good feel and no stickiness. Is 1: 1 or more, more preferably 1: 2 or more, and even more preferably 1: 3 or more, and preferably from 1:50 or less, more preferably 1:30 or less, still more preferably from the viewpoint of film durability. It is less than 1:20.

  As a mixing ratio of the cellulose fiber composite and the organic medium of the present invention and the solvent, for example, a ratio in which the solvent is 60% or more and 95% or less of the whole dispersion is preferable.

<Step 2>
The dispersion obtained in step 1 is applied to a molded article having a solid surface such as glass or resin. Examples of the method of application include a method of application using an applicator, a bar coater, a spin coater and the like. The thickness of the coating film is preferably 10 μm or more, more preferably 20 μm or more, still more preferably 30 μm from the viewpoint of synovial velocity and durability, and preferably 2000 μm or less, more preferably 1500 μm from the viewpoint of coatability. The following is more preferably 1200 μm or less.

  The coating is then dried. Drying conditions may be under reduced pressure or normal pressure, and a temperature range of 15 to 75 ° C. is preferable. Moreover, as time for drying, 1 hour or more and 50 hours or less are preferable.

  In this way, a membrane is formed and a shaped body having a membrane is obtained.

[Molded body]
Moldings with membranes can be produced as described above, and moldings with membranes as described above are encompassed by the present invention.

  By applying the membrane of the present invention to a solid surface as described above, the solid surface can be modified to a synovial fluid surface. Accordingly, the present invention includes the aforementioned membrane for modifying a solid surface to a synovial fluid surface. Since the film of the present invention is excellent in feel and does not stick, it is used as a packaging material for various applications, for example, daily necessities, cosmetics, home appliances, blister containers, packaging containers such as trays and lids for lunch boxes, food containers, It can be suitably used for industrial trays and the like used for transportation and protection of industrial parts.

[Dispersion for membrane]
In one embodiment of the present invention, a cellulose fiber composite and an organic compound in which a silicone compound is bound as a modifying group to one or more selected from the carboxy group and hydroxy group of cellulose fiber having a carboxy group content of 0.1 mmol / g or more. A membrane dispersion is provided having a medium. Such a film dispersion may be provided as a coating solution for forming a film. The film dispersion may contain, if necessary, the solvent and other components listed in the above-mentioned [Method of producing a film].

  The content of the cellulose fiber composite of the present invention in the dispersion for a membrane is preferably 0.2% by mass or more, more preferably 0.3% by mass or more, still more preferably 0 from the viewpoint of feel and stickiness of the membrane. .4% by mass or more. In addition, from the same viewpoint, the content is preferably 2.0% by mass or less, more preferably 1.8% by mass or less, and still more preferably 1.7% by mass or less.

  The content of the organic medium in the dispersion for a film is preferably 8.0% by mass or more, more preferably 8.2% by mass or more, still more preferably 8.3% by mass or more from the viewpoint of feel and stickiness of the film It is. In addition, from the same viewpoint, the content is preferably 9.8% by mass or less, more preferably 9.7% by mass or less, and still more preferably 9.6% by mass or less.

  The content of the solvent in the membrane dispersion is preferably 80% by mass or more, more preferably 85% by mass or more, still more preferably 88% by mass or more, from the viewpoint of sufficiently dispersing the cellulose fiber composite of the present invention. It is. Further, from the viewpoint of shortening the film formation time, the content is preferably 96% by mass or less, more preferably 94% by mass or less, and still more preferably 92% by mass or less.

  Hereinafter, the present invention will be specifically described by way of examples. Note that this example is merely an example of the present invention and does not mean any limitation. Parts in the examples are parts by weight unless otherwise stated. In addition, "atmospheric pressure" shows 101.3 kPa and "room temperature" shows 25 degreeC.

[Average fiber diameter of cellulose fiber and cellulose fiber composite, average fiber length, average aspect ratio]
Water is added to a cellulose fiber or cellulose fiber composite to prepare a dispersion having a concentration of 0.0001% by mass, and the dispersion is dropped on mica (mica) and dried to obtain an observation sample as an observation sample. Force microscope (AFM, Nanoscope III Tapping mode AFM, manufactured by Digital instrument Co., Ltd., using a probe from Nano Sensors, Point Probe (NCH)), cellulose fiber in the observation sample or fiber of cellulose fiber complex Measure the height. At that time, in a microscope image in which the cellulose fibers can be confirmed, 100 or more of the cellulose fibers are extracted, and the average fiber diameter is calculated from the height of the fibers. The average fiber length is calculated from the distance in the fiber direction. The average aspect ratio is calculated from the average fiber length / average fiber diameter, and the standard deviation is also calculated.

[Carboxyl group content of cellulose fiber and cellulose fiber complex]
A dry mass of 0.5 g of cellulose fiber or cellulose fiber complex is placed in a 100 mL beaker, and ion-exchanged water or a mixed solvent of methanol / water = 2/1 is added to make a total of 55 mL, to which 5 mL of 0.01 M aqueous sodium chloride solution is added. In addition, a dispersion is prepared, and the dispersion is stirred until the cellulose fiber or cellulose fiber composite is sufficiently dispersed. The pH is adjusted to 2.5 to 3 by adding 0.1 M hydrochloric acid to this dispersion, and a 0.05 M aqueous solution of sodium hydroxide is added using an automatic titrator (trade name "AUT-710" manufactured by Toa DK Co., Ltd.). The solution is dropped on the dispersion under the condition of a waiting time of 60 seconds, the value of the conductivity and pH is measured every minute, and the measurement is continued until the pH becomes around 11, to obtain a conductivity curve. From this conductivity curve, the sodium hydroxide titer is determined, and the carboxy group content of the cellulose fiber or cellulose fiber composite is calculated by the following equation.
Carboxy group content (mmol / g) = sodium hydroxide titer × sodium hydroxide aqueous solution concentration (0.05 M) / mass of cellulose fiber or cellulose fiber composite (0.5 g)

[Aldehyde group content of oxidized cellulose fiber and cellulose fiber composite]
In a beaker, 100.0 g of oxidized cellulose fiber or cellulose fiber composite (solid content concentration: 1.0% by mass), acetate buffer (pH 4.8), 0.33 g of 2-methyl-2-butene, 0 sodium chlorite Add .45 g and stir at room temperature for 16 hours to oxidize the aldehyde group. After completion of the reaction, the reaction product is washed with ion-exchanged water to obtain an oxidized cellulose fiber or cellulose fiber composite in which the aldehyde group is oxidized. The reaction mixture is freeze-dried and the obtained dried product is subjected to the measurement of the carboxy group content of the oxidized cellulose fiber or cellulose fiber composite by the method described above, and the oxidized cellulose fiber or cellulose fiber composite in which the aldehyde group is oxidized Calculate the body carboxy group content. Subsequently, the aldehyde group content of the oxidized cellulose fiber or cellulose fiber composite is calculated by the formula 1.

  Aldehyde group content (mmol / g) = (Carboxyl group content of oxidized cellulose fiber or cellulose fiber composite obtained by oxidizing aldehyde group)-(Carboxyl group content of oxidized cellulose fiber or cellulose fiber composite) ... Formula 1

[Solid concentration in dispersion]
It is carried out using a halogen moisture meter MOC-120H (manufactured by Shimadzu Corporation). The measurement is performed every 30 seconds at 150 ° C. constant temperature with respect to 1 g of the sample, and the value of which the mass loss is 0.1% or less is taken as the solid content concentration.

[Average binding amount and introduction ratio of modifying groups of cellulose fiber composite (ion binding)]
The binding amount of the modifying group is determined by the following IR measurement method, and the average binding amount and the introduction ratio are calculated by the following formula. Specifically, the IR measurement is performed by measuring dried cellulose fiber or cellulose fiber complex by the ATR method using an infrared absorption spectrometer (IR) Nicolet 6700 (manufactured by Thermo Fisher Scientific Co., Ltd.) The average bonding amount and the introduction rate of the modifying group are calculated by
Bonding amount of modifying group (mmol / g) = [carboxy group content of cellulose fiber (mmol / g)] × [(peak intensity of 1720 cm ⁻¹ of cellulose fiber—1720 cm ⁻ of cellulose fiber complex after introducing modifying group Peak intensity of ¹ ) 1720 cm ^-1 peak intensity of cellulose fiber]
Peak intensity at 1720 cm ^-1 : Peak intensity derived from carbonyl group of carboxylic acid Introduction rate of modifying group (%) = {Attachment amount of modifying group (mmol / g) / Carboxy group content in cellulose fiber before introduction (%) mmol / g)} × 100

[Average binding amount and introduction ratio of modifying groups of cellulose fiber composite (amide bond)]
The average bonding amount of the modifying group is calculated by the following formula.
Bonding amount of modifying group (mmol / g) = carboxyl group content in cellulose fiber before introducing modifying group (mmol / g) -carboxyl group content in cellulose fiber composite after introducing modifying group (mmol / g)
Rate of introduction of modifying group (%) = {Attached amount of modifying group (mmol / g) / Carboxy group content in cellulose fiber before introduction (mmol / g)} × 100

[Preparation of Cellulose Fiber Dispersion]
Preparation Example 1 (Dispersion of oxidized cellulose fiber obtained by reacting N-oxyl compound with natural cellulose fiber)
Softwood bleached kraft pulp (Fletcher Challenge Canada, trade name "Machenzie", CSF 650 ml) was used as a natural cellulose fiber. As TEMPO, a commercial item (manufactured by ALDRICH, Free radical, 98% by mass) was used. A commercially available product (manufactured by Wako Pure Chemical Industries, Ltd.) was used as sodium hypochlorite. A commercially available product (manufactured by Wako Pure Chemical Industries, Ltd.) was used as sodium bromide.

  First, 100 g of softwood bleached kraft pulp fiber is sufficiently stirred with 9900 g of ion-exchanged water, and then, with respect to 100 g of the pulp mass, 1.25 mass% of TEMPO, 12.5 mass% of sodium bromide, sodium hypochlorite 28 .4 wt% were added in this order. The pH was kept at 10.5 by dropwise addition of 0.5 M sodium hydroxide using a pH stud. The reaction was carried out for 120 minutes (20 ° C.), after which the dropping of sodium hydroxide was stopped to obtain an oxidized pulp. The resulting oxidized pulp was thoroughly washed with ion exchanged water and then subjected to a dehydration treatment. After that, 3.9 g of oxidized pulp and 296.1 g of ion-exchanged water were finely pulverized twice at 245 MPa using a high-pressure homogenizer (Starburst Lab HJP-2505 manufactured by Sugino Machine Co., Ltd.) to obtain an oxidized cellulose fiber dispersion ( A solid concentration of 1.3% by mass was obtained. The average fiber diameter of this cellulose fiber was 3.3 nm, and the carboxy group content was 1.62 mmol / g.

Preparation Example 2 (Dispersion of Oxidized Cellulose Fiber in which Aldehyde Group is Reduced)
After 3846.15 g (solid content concentration 1.3 mass%) of the oxidized cellulose fiber dispersion obtained in Preparation Example 1 is charged into a beaker, and a 1 M aqueous solution of sodium hydroxide is added thereto to adjust the pH to about 10, sodium borohydride is added Was charged, reacted at room temperature for 3 hours, and subjected to aldehyde reduction treatment. After completion of the reaction, 405 g of 1 M aqueous hydrochloric acid and 4286 g of ion-exchanged water are added to make a 0.7 mass% aqueous solution, which is reacted at room temperature for 1 hour to perform protonation, washed with ion exchanged water after the reaction is completed, hydrochloric acid and salts Removed. Finally, solvent substitution was performed with isopropyl alcohol to obtain an oxidized cellulose fiber dispersion in which the aldehyde group was subjected to reduction treatment. The average fiber diameter of the obtained oxidized cellulose fiber dispersion (solid content concentration: 2.0% by mass) obtained by reducing the aldehyde group was 3.3 nm, and the carboxy group content was 1.62 mmol / g.

[Preparation of Cellulose Fiber Complex]
Production Example 1
In a beaker equipped with a magnetic stirrer and a stirrer, 300 g (solid content concentration: 2.0% by mass) of the oxidized cellulose fiber dispersion obtained in Preparation Example 2 was charged. Subsequently, an amino-modified silicone (BY16-209, manufactured by Toray Dow Corning Co., Ltd., abbreviated as “silicone 1”) is added in an amount corresponding to 0.5 mol of amino group to 1 mol of carboxy group of oxidized cellulose fiber. Charged, 100 g of isopropyl alcohol was added and the mixture was allowed to react at room temperature (25 ° C.) for 14 hours. After completion of the reaction, the reaction solution is filtered, washed with isopropyl alcohol and then stirred for 2 minutes with an ultrasonic homogenizer (US-300E, manufactured by Nippon Seiki Seisakusho Co., Ltd.), and then high pressure homogenizer (Sugino Machine Co., Ltd., Starburst Lab HJP-25005) By finely processing at 100 MPa for 1 pass, and at 150 MPa for 9 passes, a cellulose fiber composite in which an amino-modified silicone is linked to an oxidized cellulose fiber via an ionic bond was obtained. The obtained cellulose fiber composite was in the state of isopropyl alcohol dispersion. The introduction rate of the modifying group was 40% of the carboxy group of the cellulose fiber. The average fiber diameter of the obtained cellulose fiber composite was 3.3 nm.

Production Examples 2 to 5 and 7
A cellulose fiber composite was obtained in the same manner as in Production Example 1 except that the silicone compounds and the like and the preparation amount were changed as shown in Table 1. The details of the silicone compound and the like used in each production example are as follows.
Silicone 1: By Toray Dow Corning Co., Ltd., BY16-209 (Kinematic viscosity: 500, Amino equivalent weight: 1800)
Silicone 2: Toray Dow Corning Co., Ltd. SF8417 (Kinematic viscosity: 1200, amino equivalent: 1700)
Silicone 3: Toray Dow Corning Co., Ltd. FZ-3760 (Kinematic viscosity: 220, amino equivalent: 1600)
Dodecylamine: Wako Pure Chemical Industries polyoxyalkylene glycol amine: HUNTSMAN product, JEFFAMINE (registered trademark) M2070

Production Example 6
In a beaker equipped with a magnetic stirrer and a stirrer, 300 g (solid content concentration: 1.2% by mass) of the dispersion of the cellulose fiber composite obtained in Production Example 1 was charged. Subsequently, dodecylamine is charged in an amount corresponding to 0.5 mol of amino group to 1 mol of carboxyl group of the cellulose fiber complex, 100 g of isopropyl alcohol is added, and the mixture is reacted at room temperature (25 ° C.) for 14 hours I did. After completion of the reaction, in the same manner as in Production Example 1, a cellulose fiber composite in which amino-modified silicone and dodecylamine were linked via an ionic bond was obtained.

  Raw materials and the like in each production example are summarized in Table 1.

  The charged amount in Table 1 is the amount (mol) of amino group to 1 mol of carboxy group.

[Production of a membrane]
Example 1
Using the cellulose fiber composite obtained in Production Example 1, a membrane was produced as follows. Cellulose fibers in cellulose fiber composite: cellulose fiber composite, squalane and solvent such that squalane (organic medium) is at a weight ratio of 1:20, and solvent is 90% by mass of the whole dispersion. The mixture was mixed with (isopropyl alcohol) and stirred in a screw tube at room temperature for 30 minutes. Thereafter, the mixture was defoamed by stirring at 2200 rpm for 2 minutes using an automatic revolving stirrer Awatori Neritaro (manufactured by Shinky Co., Ltd.) to obtain a dispersion for a coating film. The obtained dispersion for a coating film was coated on a glass petri dish so as to have a thickness of 10 mm, and dried at room temperature for 48 hours to volatilize isopropyl alcohol to obtain a film having a thickness of 1000 μm.

Examples 2 to 8 and Comparative Example 1
A membrane was obtained in the same manner as in Example 1 except that the type of cellulose fiber composite and the mass ratio of cellulose fiber to organic medium were changed as shown in Table 2. The results are shown in Table 2.

[Evaluation of membrane]
Test example 1 (feeling evaluation)
The film produced in each of the above Examples and Comparative Examples (target products) was evaluated by the following evaluation criteria using three expert scorers, and the value obtained by rounding off the average value was taken as the touch evaluation. The results are shown in Table 2. In addition, the film produced by the comparative example 1 was used as a comparative product.
5: The target product is very smooth.
4: The target product is smoother.
3: The target product and the comparative product are equal.
2: The comparison product is smoother.
1: The comparison product is very smooth.

Test example 2 (stickiness evaluation)
The film produced in each of the above Examples and Comparative Examples (target products) was evaluated by the following evaluation criteria using three expert scorers, and the value obtained by rounding off the average value was taken as the touch evaluation. The results are shown in Table 2. In addition, the film produced by the comparative example 1 was used as a comparative product.
5: The target product is not very sticky.
4: The target product is not sticky.
3: The target product and the comparative product are equal.
2: The comparison product is not sticky.
1: The comparison product is not very sticky.

  In addition, in Table 2, a mass ratio is a mass ratio (cellulose fiber: organic medium) of the cellulose fiber and the organic medium in a cellulose fiber composite.

The following was found from the above table.
In the examples in which the silicone compound was used as the modifying group, the feel and feel were all good. On the other hand, Comparative Example 1 in which the silicone compound was not used as the modifying group was inferior to the example in terms of feel and stickiness.

  The cellulose fiber composite of the present invention can be used in the material field of packaging containers for cosmetics and food.

Claims (4)

  A cellulose fiber composite comprising, as a modifying group, a silicone compound bonded to at least one selected from the carboxy group and hydroxyl group of a cellulose fiber having a carboxy group content of 0.1 mmol / g or more.   The cellulose fiber composite according to claim 1, wherein the cellulose fiber composite is one in which a modifying group is bonded to a carboxy group of cellulose fiber.   The cellulose fiber composite according to claim 1 or 2, wherein the silicone compound is an amino-modified silicone compound.   The cellulose fiber composite according to any one of claims 1 to 3, wherein the average fiber diameter of the cellulose fiber composite is 0.1 to 200 nm.