JP6988269B2 - Fibrous Cellulose-Containing Compositions and Paints - Google Patents

Description

The present invention relates to fibrous cellulose-containing compositions and paints.

In recent years, due to the substitution of petroleum resources and increasing environmental awareness, materials using reproducible natural fibers have been attracting attention. Among natural fibers, fibrous cellulose having a fiber diameter of 10 to 50 μm, particularly fibrous cellulose (pulp) derived from wood, has been widely used mainly as paper products.

As the fibrous cellulose, fine fibrous cellulose having a fiber diameter of 1 μm or less is also known. Fine fibrous cellulose is attracting attention as a new material, and its uses are wide-ranging. For example, sheets containing fine fibrous cellulose, resin complexes, and thickeners are being developed.

It is also being considered to apply fibrous cellulose to paints. Patent Document 1 describes a water-based coating composition containing a cellulose fiber having a number average fiber diameter of 2 nm or more and 500 nm or less, a water-based resin, and a colorant.

Japanese Unexamined Patent Publication No. 2016-69618

The present inventors have considered using fine fibrous cellulose as a thickener for paints. However, it was found that there is room for improvement in the coatability of the paint when the fine fibrous cellulose is contained in the paint. The present invention is an object to be solved to provide a fibrous cellulose-containing composition and a coating material having improved coatability.

As a result of diligent studies to solve the above problems, the present inventors have found that the coatability of the fibrous cellulose-containing composition can be improved by adding a water-soluble compound or saccharide having a specific functional group. I found it. The present invention has been completed based on these findings.
The present invention has the following configurations.

[1] A fibrous cellulose-containing composition containing (a) a fibrous cellulose having a fiber width of 1000 nm or less and (b) a water-soluble compound or a saccharide having a molecular weight of 200 or less having a functional group capable of forming a hydrogen bond. thing.
[2] The content of a water-soluble compound having a molecular weight of 200 or less or a saccharide having a functional group capable of forming a hydrogen bond is 1 part by mass or more with respect to 100 parts by mass of fibrous cellulose, according to [1]. Fibrous cellulose-containing composition.
[3] The fibrous cellulose-containing composition according to [1] or [2], wherein the functional group is a carbonyl group or an amino group.
[4] The fibrous cellulose-containing composition according to any one of [1] to [3], wherein the water-soluble compound is a urea derivative.
[5] The fibrous cellulose-containing composition according to [1] or [2], wherein the saccharide is a trehalose derivative.
[6] The fibrous cellulose-containing composition according to any one of [1] to [5], wherein the surface roughness Ra of the coating film obtained under the following conditions is 0.20 μm or less.
(conditions)
A coating obtained by mixing the fibrous cellulose-containing composition, 156 parts by mass of an acrylic resin with respect to 1 part by mass of the fibrous cellulose, and 44 parts by mass of polyisocyanate with respect to 1 part by mass of the fibrous cellulose. The liquid is applied to a smooth polyethylene terephthalate plate to a thickness of 30 μm using an applicator, and immediately after the application, it is dried at 80 ° C. for 30 minutes.
[7] The fibrous form according to any one of [1] to [6], wherein the total amount of the fibrous cellulose, the saccharide or the water-soluble compound and water is 90% by mass or more with respect to the entire composition. Cellulose-containing composition.
[8] The fibrous cellulose-containing composition according to any one of [1] to [7], wherein the content of the saccharide or the water-soluble compound is 10 parts by mass or more with respect to 100 parts by mass of the fibrous cellulose.
[9] Any one of [1] to [8] having a viscosity of 40,000 mPa · s or less measured under the conditions of 23 ° C. and a rotation speed of 3 rpm, where the solid content concentration of the fibrous cellulose is 0.4% by mass. The fibrous cellulose-containing composition according to.
[10] The description according to any one of [1] to [9], wherein the fibrous cellulose is used as a dispersion liquid, and the supernatant yield when the supernatant separated from the dispersion liquid under the following conditions is recovered is 80% by mass or more. Fibrous cellulose-containing composition.
(conditions)
The dispersion of fibrous cellulose is adjusted to a solid content concentration of 0.2% by mass, and centrifuged at 12000 G for 10 minutes using a cooling high-speed centrifuge. The obtained supernatant was collected, and the solid content concentration of the supernatant was measured. The yield of fibrous cellulose is determined based on the following formula.
Supernatant yield (%) = supernatant solid content concentration (%) /0.2 × 100
[11] The fibrous cellulose-containing composition according to any one of [1] to [10], wherein the Young's modulus of the coating film obtained under the following conditions is 0.7 GPa or more.
(conditions)
A coating obtained by mixing the fibrous cellulose-containing composition, 156 parts by mass of an acrylic resin with respect to 1 part by mass of the fibrous cellulose, and 44 parts by mass of polypropylene with respect to 1 part by mass of the fibrous cellulose. The liquid is applied to a smooth polypropylene plate to a thickness of 30 μm using an applicator, and immediately after the application, it is dried at 80 ° C. for 30 minutes.
[12] The fibrous cellulose-containing composition according to any one of [1] to [11], which further comprises an enzyme.
[13] The fibrous cellulose-containing composition according to any one of [1] to [12] for use in paints.
[14] The fibrous cellulose-containing composition according to any one of [1] to [12] for use in a thickener.
[15] A coating material containing the fibrous cellulose-containing composition according to any one of [1] to [14].
[16] A kit for a fibrous cellulose-containing composition, which is a combination of fibrous cellulose having a fiber width of 1000 nm or less and a water-soluble compound having a functional group capable of forming a hydrogen bond and having a molecular weight of 200 or less, or a saccharide.

According to the present invention, it is possible to provide a fibrous cellulose-containing composition and a coating material having improved coatability.

FIG. 1 is a graph showing the relationship between the amount of NaOH dropped and the electrical conductivity with respect to a fiber raw material having a phosphoric acid group. FIG. 2 is a graph showing the relationship between the amount of NaOH dropped and the electrical conductivity with respect to the fiber raw material having a carboxyl group.

Hereinafter, the present invention will be described in detail. The description of the constituent elements described below may be based on typical embodiments and specific examples, but the present invention is not limited to such embodiments.

The fibrous cellulose-containing composition of the present invention has a fibrous cellulose having a fiber width of 1000 nm or less (sometimes referred to as "fine fibrous cellulose") and a water-soluble composition having a functional group capable of forming a hydrogen bond and having a molecular weight of 200 or less. Contains sex compounds or sugars (these may be referred to as "specific components").

(Fibrous cellulose)
The fibrous cellulose-containing composition of the present invention contains fine fibrous cellulose. The fine fibrous cellulose is preferably a fiber having an ionic substituent, and in this case, the ionic substituent is preferably an anionic substituent (hereinafter, also referred to as an anionic substituent). Examples of the anionic group include a phosphate group or a substituent derived from a phosphate group (sometimes simply referred to as a phosphate group), a carboxyl group or a substituent derived from a carboxyl group (sometimes simply referred to as a carboxyl group), and the like. In addition, it is preferably at least one selected from a sulfone group or a substituent derived from a sulfone group (sometimes simply referred to as a sulfone group), and at least one selected from a phosphate group and a carboxyl group. Is more preferable, and a phosphoric acid group is particularly preferable.

The raw material for fibrous cellulose for obtaining fine fibrous cellulose is not particularly limited, but pulp is preferable because it is easily available and inexpensive. Examples of the pulp include wood pulp, non-wood pulp, and deinked pulp. Examples of wood pulp include broadleaf kraft pulp (LBKP), coniferous kraft pulp (NBKP), sulfite pulp (SP), dissolved pulp (DP), soda pulp (AP), unbleached kraft pulp (UKP), and oxygen bleached craft. Examples thereof include chemical pulp such as pulp (OKP). Examples thereof include semi-chemical pulp such as semi-chemical pulp (SCP) and chemiground wood pulp (CGP), mechanical pulp such as crushed wood pulp (GP) and thermomechanical pulp (TMP, BCTMP), but are not particularly limited. Examples of the non-wood pulp include cotton pulp such as cotton linter and cotton lint, non-wood pulp such as hemp, straw and bagasse, cellulose isolated from sea squirts and seaweed, chitin, chitosan and the like, but are not particularly limited. .. Examples of the deinked pulp include deinked pulp made from recycled paper, but the pulp is not particularly limited. As the pulp of this embodiment, one of the above may be used alone, or two or more of them may be mixed and used. Among the above pulps, wood pulp containing cellulose and deinked pulp are preferable in terms of availability. Among wood pulps, chemical pulp has a large cellulose ratio, so the yield of fine fibrous cellulose during fiber finening (defibration) is high, the decomposition of cellulose in the pulp is small, and the fineness of long fibers with a large axial ratio It is preferable in that fibrous cellulose can be obtained. Of these, kraft pulp and sulfite pulp are most preferably selected. Sheets containing fine fibrous cellulose of long fibers having a large axial ratio tend to obtain high strength.

The average fiber width of the fine fibrous cellulose is 1000 nm or less as observed with an electron microscope. The average fiber width is preferably 2 nm or more and 1000 nm or less, more preferably 2 nm or more and less than 1000 nm, more preferably 2 nm or more and 100 nm or less, more preferably 2 nm or more and 50 nm or less, and further preferably 2 nm or more and 10 nm or less. , Not particularly limited. When the average fiber width of the fine fibrous cellulose is less than 2 nm, it is dissolved in water as a cellulose molecule, so that the physical properties (strength, rigidity, dimensional stability) of the fine fibrous cellulose tend to be difficult to develop. .. The fine fibrous cellulose is, for example, a single fibrous cellulose having a fiber width of 1000 nm or less.

The fiber width is measured by observing the fine fibrous cellulose with an electron microscope as follows. An aqueous suspension of fine fibrous cellulose having a concentration of 0.05% by mass or more and 0.1% by mass or less was prepared, and this suspension was cast on a hydrophilized carbon film-coated grid to form a sample for TEM observation. do. If it contains wide fibers, an SEM image of the surface cast on the glass may be observed. Observation with an electron microscope image is performed at a magnification of 1000 times, 5000 times, 10000 times, or 50,000 times depending on the width of the constituent fibers. However, the sample, observation conditions and magnification should be adjusted so as to satisfy the following conditions.

(1) A straight line X is drawn at an arbitrary position in the observation image, and 20 or more fibers intersect the straight line X.
(2) A straight line Y that intersects the straight line perpendicularly is drawn in the same image, and 20 or more fibers intersect the straight line Y.

The width of the fiber intersecting the straight line X and the straight line Y is visually read with respect to the observation image satisfying the above conditions. In this way, at least three sets of images of the non-overlapping surface portions are observed, and the widths of the fibers intersecting the straight lines X and Y are read for each image. In this way, at least 20 fibers × 2 × 3 = 120 fibers are read. The average fiber width of the fine fibrous cellulose (sometimes simply referred to as "fiber width") is the average value of the fiber widths read in this way.

The fiber length of the fine fibrous cellulose is not particularly limited, but is preferably 0.1 μm or more and 1000 μm or less, more preferably 0.1 μm or more and 800 μm or less, and particularly preferably 0.1 μm or more and 600 μm or less. By setting the fiber length within the above range, the destruction of the crystal region of the fine fibrous cellulose can be suppressed, and the slurry viscosity of the fine fibrous cellulose can be set within an appropriate range. The fiber length of the fine fibrous cellulose can be obtained by image analysis by TEM, SEM, or AFM.
The axial ratio (fiber length / fiber width) of the fibrous cellulose is not particularly limited, but is preferably 20 or more and 10000 or less, and more preferably 50 or more and 1000 or less. By setting the axial ratio to the above lower limit value or more, it is easy to form a fine fiber-containing sheet, and it is easy to obtain sufficient viscosity when a solvent dispersion is produced. By setting the axial ratio to the above upper limit value or less, it is preferable in that handling such as dilution becomes easy when, for example, fibrous cellulose is treated as an aqueous dispersion.

The fine fibrous cellulose preferably has an I-type crystal structure. Here, the fact that the fine fibrous cellulose has an I-type crystal structure can be identified in the diffraction profile obtained from the wide-angle X-ray diffraction photograph using CuKα (λ = 1.5418 Å) monochromatic with graphite. Specifically, it can be identified by having typical peaks at two positions, 2θ = 14 ° or more and 17 ° or less and 2θ = 22 ° or more and 23 ° or less.

The ratio of the type I crystal structure to the fine fibrous cellulose is preferably 30% or more, more preferably 40% or more, still more preferably 50% or more. In this case, further excellent performance can be expected in terms of heat resistance and the development of a low coefficient of linear thermal expansion. The crystallinity is determined by a conventional method from the X-ray diffraction profile measured and the pattern (Seagal et al., Textile Research Journal, Vol. 29, p. 786, 1959).

The fine fibrous cellulose preferably has a phosphoric acid group or a substituent derived from the phosphoric acid group. The phosphoric acid group is a divalent functional group obtained by removing the hydroxyl group from phosphoric acid. Specifically, it is a group represented by _{−PO 3} H _2. Substituents derived from a phosphoric acid group include substituents such as a group obtained by decomposing a phosphoric acid group, a salt of a phosphoric acid group, and a phosphoric acid ester group, and even if it is an ionic substituent, it is a nonionic substituent. It may be a group.

In the present invention, the phosphate group or the substituent derived from the phosphoric acid group may be a substituent represented by the following formula (1).

In equation (1), a, b, m and n each independently represent an integer (where a = b × m); α and α ′ independently represent R or OR, respectively. R is a hydrogen atom, a saturated-linear hydrocarbon group, a saturated-branched chain hydrocarbon group, a saturated-cyclic hydrocarbon group, an unsaturated-linear hydrocarbon group, an unsaturated-branched chain hydrocarbon group. , An aromatic group, or an inducing group thereof; β is a monovalent or higher cation consisting of an organic or inorganic substance.

<Introduction of phosphate group>
The introduction of the phosphoric acid group is carried out by reacting the fiber raw material containing cellulose with at least one selected from a compound having a phosphoric acid group and a salt thereof (hereinafter referred to as "phosphorylation reagent" or "compound A"). Can be done by. Such phosphorylation reagents may be mixed with the dry or wet fiber raw material in the form of powder or aqueous solution. As another example, a powder or an aqueous solution of a phosphorylation reagent may be added to the slurry of the fiber raw material.

The introduction of the phosphoric acid group can be carried out by reacting the fiber raw material containing cellulose with at least one selected from a compound having a phosphorylation group and a salt thereof (phosphorylation reagent or compound A). This reaction may be carried out in the presence of at least one selected from urea and its derivatives (hereinafter referred to as "Compound B").

As an example of the method of allowing the compound A to act on the fiber raw material in the coexistence of the compound B, there is a method of mixing the powder or the aqueous solution of the compound A and the compound B with the fiber raw material in a dry state or a wet state. Another example is a method of adding a powder or an aqueous solution of compound A and compound B to a slurry of a fiber raw material. Of these, since the reaction uniformity is high, a method of adding an aqueous solution of compound A and compound B to a dry fiber raw material, or adding a powder or aqueous solution of compound A and compound B to a wet fiber raw material. The method is preferred. Further, compound A and compound B may be added at the same time or separately. Further, the compound A and the compound B to be tested in the reaction may be added as an aqueous solution first, and the excess chemical solution may be removed by pressing. The form of the fiber raw material is preferably cotton-like or thin sheet-like, but is not particularly limited.

The compound A used in this embodiment is at least one selected from a compound having a phosphoric acid group and a salt thereof.
Examples of the compound having a phosphoric acid group include phosphoric acid, a lithium salt of phosphoric acid, a sodium salt of phosphoric acid, a potassium salt of phosphoric acid, an ammonium salt of phosphoric acid, and the like, but the compound is not particularly limited. Examples of the lithium salt of phosphoric acid include lithium dihydrogen phosphate, dilithium hydrogen phosphate, trilithium phosphate, lithium pyrophosphate, and lithium polyphosphate. Examples of the sodium salt of phosphoric acid include sodium dihydrogen phosphate, disodium hydrogen phosphate, trisodium phosphate, sodium pyrophosphate, sodium polyphosphate and the like. Examples of the potassium salt of phosphoric acid include potassium dihydrogen phosphate, dipotassium hydrogen phosphate, tripotassium phosphate, potassium pyrophosphate, potassium polyphosphate and the like. Examples of the ammonium salt of phosphoric acid include ammonium dihydrogen phosphate, diammonium hydrogen phosphate, triammonium phosphate, ammonium pyrophosphate, and ammonium polyphosphate.

Of these, phosphoric acid and phosphoric acid are selected from the viewpoints of high efficiency of introduction of phosphoric acid group, easy improvement of defibration efficiency in the defibration step described later, low cost, and easy industrial application. A sodium salt, a potassium salt of phosphoric acid, or an ammonium salt of phosphoric acid is preferable. Sodium dihydrogen phosphate or disodium hydrogen phosphate is more preferred.

Further, the compound A is preferably used as an aqueous solution because the uniformity of the reaction is enhanced and the efficiency of introducing the phosphoric acid group is increased. The pH of the aqueous solution of compound A is not particularly limited, but is preferably 7 or less because the efficiency of introducing a phosphoric acid group is high, and more preferably pH 3 or more and pH 7 or less from the viewpoint of suppressing hydrolysis of pulp fibers. The pH of the aqueous solution of the compound A may be adjusted, for example, by using a compound having a phosphoric acid group in combination with an acidic compound and an alkaline compound, and changing the amount ratio thereof. The pH of the aqueous solution of the compound A may be adjusted by adding an inorganic alkali or an organic alkali to the compound having a phosphoric acid group and showing acidity.

The amount of compound A added to the fiber raw material is not particularly limited, but when the amount of compound A added is converted to the phosphorus atomic weight, the amount of phosphorus atom added to the fiber raw material (absolute dry mass) is 0.5% by mass or more and 100% by mass. The following is preferable, 1% by mass or more and 50% by mass or less is more preferable, and 2% by mass or more and 30% by mass or less is most preferable. When the amount of phosphorus atom added to the fiber raw material is within the above range, the yield of fine fibrous cellulose can be further improved. Further, by setting the addition amount of the phosphorus atom to the fiber raw material to 100% by mass or less, the cost of the compound A to be used can be suppressed while increasing the phosphorylation efficiency.

Examples of compound B used in this embodiment include urea, biuret, 1-phenylurea, 1-benzylurea, 1-methylurea, 1-ethylurea and the like.

Compound B is preferably used as an aqueous solution like compound A. Further, since the uniformity of the reaction is enhanced, it is preferable to use an aqueous solution in which both compound A and compound B are dissolved. The amount of compound B added to the fiber raw material (absolute dry mass) is preferably 1% by mass or more and 500% by mass or less, more preferably 10% by mass or more and 400% by mass or less, and 100% by mass or more and 350% by mass or less. It is more preferably 150% by mass or more, and particularly preferably 300% by mass or less.

In addition to compound A and compound B, amides or amines may be included in the reaction system. Examples of amides include formamide, dimethylformamide, acetamide, dimethylacetamide and the like. Examples of amines include methylamine, ethylamine, trimethylamine, triethylamine, monoethanolamine, diethanolamine, triethanolamine, pyridine, ethylenediamine, hexamethylenediamine and the like. Among these, triethylamine in particular is known to act as a good reaction catalyst.

It is preferable to perform heat treatment when introducing the phosphoric acid group. As the heat treatment temperature, it is preferable to select a temperature at which the phosphate group can be efficiently introduced while suppressing the thermal decomposition and hydrolysis reaction of the fiber. Specifically, it is preferably 50 ° C. or higher and 300 ° C. or lower, more preferably 100 ° C. or higher and 250 ° C. or lower, and further preferably 130 ° C. or higher and 200 ° C. or lower. Further, a vacuum dryer, an infrared heating device, and a microwave heating device may be used for heating.

During the heat treatment, when the fiber raw material slurry containing the compound A contains water and the fiber raw material is allowed to stand for a long time, the water molecules and the dissolved compound A move to the surface of the fiber raw material as it dries. do. Therefore, the concentration of the compound A in the fiber raw material may be uneven, and the introduction of the phosphoric acid group to the fiber surface may not proceed uniformly. In order to suppress the occurrence of uneven concentration of compound A in the fiber raw material due to drying, a very thin sheet-shaped fiber raw material is used, or the fiber raw material and compound A are kneaded or stirred with a kneader or the like and dried by heating or under reduced pressure. You can take the method.

The heating device used for the heat treatment is preferably a device that can always discharge the water retained by the slurry and the water generated by the addition reaction of the fiber such as a phosphoric acid group to the hydroxyl group to the outside of the device system. Etc. are preferable. If the water in the apparatus system is constantly discharged, the hydrolysis reaction of the phosphate ester bond, which is the reverse reaction of the phosphate esterification, can be suppressed, and the acid hydrolysis of the sugar chain in the fiber can also be suppressed. , Fine fibers having a high axial ratio can be obtained.

Although the heat treatment time is affected by the heating temperature, it is preferably 1 second or more and 300 minutes or less after the water is substantially removed from the fiber raw material slurry, and more preferably 1 second or more and 1000 seconds or less. It is preferable, and it is more preferably 10 seconds or more and 800 seconds or less. In the present invention, the amount of phosphoric acid group introduced can be within a preferable range by setting the heating temperature and the heating time within appropriate ranges.

The amount of the phosphoric acid group introduced is preferably 5.20 mmol / g or less, more preferably 0.1 mmol / g or more and 3.65 mmol / g or less, and 0. .14 mmol / g or more and 3.5 mmol / g or less are even more preferable, 0.2 mmol / g or more and 3.2 mmol / g or less are further preferable, 0.4 mmol / g or more and 3.0 mmol / g or less are particularly preferable, and most preferable. Is 0.6 mmol / g or more and 2.5 mmol / g or less. By setting the amount of the phosphoric acid group introduced within the above range, it is possible to facilitate the miniaturization of the fiber raw material and enhance the stability of the fine fibrous cellulose. Further, by setting the introduction amount of the phosphoric acid group within the above range, it is possible to leave hydrogen bonds between fine fibrous celluloses while being easy to miniaturize, and good strength when used as a sheet. Expression can be expected.

The amount of the phosphoric acid group introduced into the fiber raw material can be measured by the conductivity titration method. Specifically, it is refined by a defibration treatment step, the obtained fine fibrous cellulose-containing slurry is treated with an ion exchange resin, and then the change in electrical conductivity is obtained while adding an aqueous sodium hydroxide solution. The amount of introduction can be measured.

In the conductivity titration, the addition of alkali gives the curve shown in FIG. Initially, the electrical conductivity drops sharply (hereinafter referred to as the "first region"). After that, the conductivity begins to increase slightly (hereinafter referred to as "second region"). After that, the increment of conductivity increases (hereinafter referred to as "third region"). That is, three regions appear. The boundary point between the second region and the third region is defined by the point where the second derivative value of the conductivity, that is, the amount of change in the increment (slope) of the conductivity is maximized. Of these, the amount of alkali required in the first region is equal to the amount of strongly acidic groups in the slurry used for titration, and the amount of alkali required in the second region is equal to the amount of weakly acidic groups in the slurry used for titration. Will be equal. When the phosphoric acid group causes condensation, the weakly acidic group is apparently lost, and the amount of alkali required for the second region is smaller than the amount of alkali required for the first region. On the other hand, since the amount of strongly acidic groups is the same as the amount of phosphorus atoms regardless of the presence or absence of condensation, it is simply referred to as the amount of phosphate group introduced (or the amount of phosphate groups) or the amount of substituents introduced (or the amount of substituents). When it is said, it means the amount of strongly acidic groups. That is, the amount of alkali (mmol) required in the first region of the curve shown in FIG. 1 is divided by the solid content (g) in the slurry to be titrated to obtain the amount of substituent introduced (mmol / g).

The phosphoric acid group introduction step may be performed at least once, but may be repeated a plurality of times. In this case, more phosphate groups are introduced, which is preferable.

<Introduction of carboxyl group>
In the present invention, when the fine fibrous cellulose has a carboxyl group, for example, the fiber raw material is subjected to an oxidation treatment such as a TEMPO (2,2,6,6-tetramethylpiperidin-1-oxyl) oxidation treatment. Alternatively, a carboxyl group can be introduced by treatment with a compound having a group derived from a carboxylic acid, a derivative thereof, or an acid anhydride thereof or a derivative thereof.

The compound having a carboxyl group is not particularly limited, and examples thereof include dicarboxylic acid compounds such as maleic acid, succinic acid, phthalic acid, fumaric acid, glutaric acid, adipic acid and itaconic acid, and tricarboxylic acid compounds such as citric acid and aconitic acid. ..

The acid anhydride of the compound having a carboxyl group is not particularly limited, and examples thereof include acid anhydrides of dicarboxylic acid compounds such as maleic anhydride, succinic anhydride, phthalic anhydride, glutaric anhydride, adipic anhydride, and itaconic anhydride. Will be.

The derivative of the compound having a carboxyl group is not particularly limited, and examples thereof include an acid anhydride derivative of the compound having a carboxyl group and an acid anhydride derivative of the compound having a carboxyl group. The imide of the acid anhydride of the compound having a carboxyl group is not particularly limited, and examples thereof include an imide of a dicarboxylic acid compound such as maleimide, succinateimide, and phthalateimide.

The derivative of the acid anhydride of the compound having a carboxyl group is not particularly limited. For example, at least a part of the hydrogen atom of the acid anhydride of a compound having a carboxyl group, such as dimethylmaleic acid anhydride, diethylmaleic acid anhydride, diphenylmaleic acid anhydride, etc., is a substituent (for example, an alkyl group, a phenyl group, etc.). ) Is substituted.

The amount of the carboxyl group introduced is preferably 0.1 mmol / g or more and 3.65 mmol / g or less, and more preferably 0.14 mmol / g or more and 3.5 mmol / g or less per 1 g (mass) of fine fibrous cellulose. It is more preferably 0.2 mmol / g or more and 3.2 mmol / g or less, particularly preferably 0.4 mmol / g or more and 3.0 mmol / g or less, and most preferably 0.6 mmol / g or more and 2.5 mmol / g or less.
The amount of the carboxyl group introduced into the fiber raw material can be measured by the conductivity titration method. In the conductivity titration, the addition of alkali gives the curve shown in FIG. The amount of alkali (mmol) required in the first region of the curve shown in FIG. 2 is divided by the solid content (g) in the slurry to be titrated to obtain the amount of substituent introduced (mmol / g).

<Alkaline treatment process>
In the case of producing fine fibrous cellulose, an alkali treatment may be performed on the fiber raw material between the substituent introduction step and the defibration treatment step described later. The alkaline treatment method is not particularly limited, and examples thereof include a method of immersing the substituent-introduced fiber in an alkaline solution.

The alkaline compound contained in the alkaline solution is not particularly limited, and may be an inorganic alkaline compound or an organic alkaline compound. In this embodiment, it is preferable to use, for example, sodium hydroxide or potassium hydroxide as the alkaline compound because of its high versatility. Further, the solvent contained in the alkaline solution may be either water or an organic solvent. The solvent contained in the alkaline solution is preferably a polar solvent containing water, a polar organic solvent exemplified by alcohol, and the like, and more preferably an aqueous solvent containing at least water. As the alkaline solution, for example, an aqueous solution of sodium hydroxide or an aqueous solution of potassium hydroxide is preferable because of its high versatility.

The temperature of the alkaline solution in the alkaline treatment step is not particularly limited, but is preferably 5 ° C. or higher and 80 ° C. or lower, and more preferably 10 ° C. or higher and 60 ° C. or lower. The immersion time of the substituent-introduced fiber in the alkaline solution in the alkaline treatment step is not particularly limited, but is preferably 5 minutes or more and 30 minutes or less, and more preferably 10 minutes or more and 20 minutes or less. The amount of the alkaline solution used in the alkaline treatment is not particularly limited, but is preferably 100% by mass or more and 100,000% by mass or less, and 1000% by mass or more and 10,000% by mass or less, for example, with respect to the absolute dry mass of the substituent-introduced fiber. It is more preferable to have.

In order to reduce the amount of the alkaline solution used in the alkaline treatment step, the substituent-introduced fiber may be washed with water or an organic solvent after the substituent introduction step and before the alkaline treatment step. After the alkali treatment step and before the defibration treatment step, it is preferable to wash the alkali-treated substituent-introduced fiber with water or an organic solvent from the viewpoint of improving handleability.

<Acid treatment process>
In the case of producing fine fibrous cellulose, the fiber raw material may be subjected to acid treatment between the step of introducing a substituent and the defibration treatment step described later. As an example of this embodiment, there is a case where the substituent introduction step, the acid treatment, the alkali treatment and the defibration treatment are performed in this order.

The temperature of the acid solution in the acid treatment is not particularly limited, but is preferably 5 ° C. or higher and 100 ° C. or lower, and more preferably 20 ° C. or higher and 90 ° C. or lower. The immersion time in the acid solution in the acid treatment is not particularly limited, but is preferably 5 minutes or more and 120 minutes or less, and more preferably 10 minutes or more and 60 minutes or less. The amount of the acid solution used in the acid treatment is not particularly limited, but is preferably 100% by mass or more and 100,000% by mass or less, and 1000% by mass or more and 10,000% by mass or less, for example, with respect to the absolute dry mass of the fiber raw material. Is more preferable.

The method of the acid treatment is not particularly limited, and examples thereof include a method of immersing the fiber raw material in an acidic liquid containing an acid. The concentration of the acidic liquid used is not particularly limited, but is preferably 10% by mass or less, more preferably 5% by mass or less, for example. The pH of the acidic solution used is not particularly limited, but is preferably 0 to 4, more preferably 1 to 3, for example. As the acid contained in the acidic liquid, for example, an inorganic acid, a sulfonic acid, a carboxylic acid or the like can be used. Examples of the inorganic acid include sulfuric acid, nitric acid, hydrochloric acid, hydrobromic acid, hydroiodic acid, hypochlorous acid, chloric acid, chloric acid, perchloric acid, phosphoric acid, boric acid and the like. Examples of the sulfonic acid include methanesulfonic acid, ethanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, trifluoromethanesulfonic acid and the like. Examples of the carboxylic acid include formic acid, acetic acid, citric acid, gluconic acid, lactic acid, oxalic acid, tartaric acid and the like. Among these, it is particularly preferable to use hydrochloric acid or sulfuric acid.

<Fiber processing (miniaturization)>
The substituent-introduced fiber is defibrated in the defibration treatment step to obtain fine fibrous cellulose. In the defibration treatment step, for example, a defibration treatment apparatus can be used. The defibrating processing device is not particularly limited, but for example, a wet atomizing device, a high-speed defibrating machine, a grinder (stone mill type crusher), a high-pressure homogenizer, an ultra-high pressure homogenizer, a high-pressure collision type crusher, a ball mill, a bead mill, a disk type refiner, etc. A conical refiner, a twin-screw kneader, a vibration mill, a homomixer under high-speed rotation, an ultrasonic disperser, a beater, etc. can be used, and the solid content concentration of fine fibrous cellulose during pulverization is appropriately set. can. Among the above-mentioned defibration processing devices, it is more preferable to use a wet atomizing device, a high-speed defibrator, a high-pressure homogenizer, and an ultra-high-pressure homogenizer, which are less affected by crushed media and have less risk of contamination. The number of defibration treatments (miniaturization) is not particularly limited, but it is preferable to perform the defibration treatment (miniaturization) a plurality of times in order to promote sufficient miniaturization. The upper limit is not particularly limited, but it is practical that the number of times is 10 or less.

In the defibration treatment step, for example, it is preferable to dilute the substituent-introduced fiber with a dispersion medium to form a slurry. As the dispersion medium, one or more selected from water and an organic solvent such as a polar organic solvent can be used. The polar organic solvent is not particularly limited, but for example, alcohols, polyhydric alcohols, ketones, ethers, esters, aprotic polar solvents and the like are preferable. Examples of alcohols include methanol, ethanol, isopropanol, n-butanol, isobutyl alcohol and the like. Examples of polyhydric alcohols include ethylene glycol, propylene glycol and glycerin. Examples of the ketone include acetone, methyl ethyl ketone (MEK) and the like. Examples of ethers include diethyl ether, tetrahydrofuran, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monon-butyl ether, propylene glycol monomethyl ether and the like. Examples of the esters include ethyl acetate, butyl acetate and the like. Examples of the aprotonic polar solvent include dimethyl sulfoxide (DMSO), dimethylformamide (DMF), dimethylacetamide (DMAc), N-methyl-2-pyrrolidinone (NMP) and the like.

<Enzyme treatment>
In the present invention, enzyme treatment may be performed. That is, the cellulose-containing composition of the present invention may contain an enzyme. In addition, the cellulose-containing composition of the present invention may contain a protein in which an enzyme is inactivated.
The enzymes that can be used in the present invention are cellulase-based enzymes and are classified into the sugar hydrolase family based on the higher-order structure of the catalytic domain having the hydrolysis reaction function of cellulose. Cellulase-based enzymes are classified into endo-glucanase and cellobiohydrolase according to their cellulolytic properties. Endo-type glucanase is highly hydrolyzable to the amorphous portion of cellulose, soluble cellooligosaccharides, or cellulose derivatives such as carboxymethyl cellulose, and randomly cleaves their molecular chains from the inside to reduce the degree of polymerization. However, endo-type glucanase has low hydrolysis reactivity with crystalline cellulose microfibrils. In contrast, cellobiohydrolase decomposes the crystalline portion of cellulose to give cellobiose. In addition, cellobiohydrolase is hydrolyzed from the end of the cellulose molecule and is also called an exo-type or processive enzyme. In the present invention, it is preferable to use end-type glucanase.

As the enzyme used in the present invention, hemicellulase-based enzymes may be used in addition to endo-type glucanase and cellobiohydrolase. Among the hemicellulase-based enzymes, xylanase, which is an enzyme that decomposes xylan, mannase, which is an enzyme that decomposes mannan, and arabanase, which is an enzyme that decomposes araban, can be mentioned. In addition, pectinase, which is an enzyme that decomposes pectin, can also be used as a hemicellulase-based enzyme. Microorganisms that produce hemicellulase-based enzymes often also produce cellulase-based enzymes.

Hemicellulose is a polysaccharide excluding pectins between cellulose microfibrils in plant cell walls. Hemicellulose is diverse and varies between plant types and cell wall layers. In wood, the secondary wall of conifers is mainly composed of glucomannan, and the secondary walls of hardwoods are mainly composed of 4-O-methylglucuronoxylan. Therefore, it is preferable to use mannase in order to obtain fine fibers from coniferous trees, and it is preferable to use xylanase in the case of hardwoods.

INDUSTRIAL APPLICABILITY According to the present invention, there is provided a method for producing a cellulose-containing composition, which comprises a step of adding an enzyme. By adding the enzyme to the fine fibrous cellulose, the fine fibrous cellulose can be reacted with the enzyme. In the present invention, it is possible to adopt a form in which the washing step of the fine fibrous cellulose is not performed after the enzyme treatment.
In the present invention, the enzyme may be inactivated after the enzyme treatment. As a method for inactivating the enzyme, a mixture of fine fibrous cellulose and enzyme is heated to 100 ° C. and allowed to stand for 30 minutes to 1 hour while maintaining the temperature, or a mixture of fine fibrous cellulose and enzyme. On the other hand, the pH may be adjusted to 10 or more by adding a strong base, but the pH is not particularly limited.
The cellulose-containing composition of the present invention can be produced by the above-mentioned method for producing a cellulose-containing composition.

The amount of the enzyme added to 1 part by mass of fibrous cellulose having a fiber width of 1000 nm or less is not particularly limited, but is preferably ^{1 × 10 -3 parts by mass or less, more preferably 1 × 10 -4} parts by mass or less, and 1 × 10 ^-5 parts by mass or less is more preferable, and 5.0 × 10 ^-6 parts by mass or less is particularly preferable. ^{The amount of the enzyme added is preferably 1 × 10 -7} parts by mass or more, more preferably 3 × 10 ^-7 parts by mass or more, and further preferably 1 × 10 ^-6 parts by mass or more with respect to 1 part by mass of fibrous cellulose. preferable.
By setting the amount of the enzyme added within the above range, grains (aggregates) in the coated product can be suppressed.

The reaction time between the fine fibrous cellulose and the enzyme is not particularly limited, but is generally preferably 1 minute to 24 hours, more preferably 1 minute to 1 hour.
The reaction temperature and reaction pH of the fine fibrous cellulose and the enzyme are preferably kept at the optimum temperature and the optimum pH of the enzyme to be used, and are generally set to 20 ° C to 80 ° C and pH 4.5 to 9.5. It is preferable to keep it.
By setting the reaction conditions within the above range, grains (aggregates) in the coated product can be suppressed.

<Coarse fibrous cellulose>
As described above, the step of obtaining fine fibrous cellulose preferably includes a step of refining the fiber raw material (coarse fibrous cellulose). At this time, most of the coarse fibrous cellulose is made finer, but a part of it may remain without being made finer. In such a case, the fibrous cellulose-containing composition of the present invention contains coarse fibrous cellulose.

With respect to the coarse fibrous cellulose contained in the fibrous cellulose-containing composition of the present invention, the cellulose dispersion is adjusted to a solid content concentration of 0.2% by mass, and a cooling high-speed centrifuge (Kokusan Co., Ltd., H-2000B) is used. It is a fibrous cellulose that precipitates when centrifuged at 12000 G for 10 minutes.

A small amount of sedimentation component means that the yield of the supernatant after centrifugation is high. The yield of the supernatant after centrifugation is preferably 80% by mass or more with respect to the total mass of the fibrous cellulose. The yield of the supernatant after centrifugation is more preferably 90% by mass or more, further preferably 95% by mass or more, and particularly preferably 99% by mass or more.

The yield of the supernatant after centrifugation of the above-mentioned fine fibrous cellulose dispersion can be measured in the present specification by the following method.
The supernatant yield after centrifuging the fine fibrous cellulose dispersion was measured by the method described below. The yield of the supernatant after centrifugation is an index of the yield of the fine fibrous cellulose, and the higher the yield of the supernatant, the higher the yield of the fine fibrous cellulose.

The fine fibrous cellulose dispersion was adjusted to a solid content concentration of 0.2% by mass, and centrifuged at 12000 G for 10 minutes using a cooling high-speed centrifuge (Kokusan Co., Ltd., H-2000B). The obtained supernatant was collected, and the solid content concentration of the supernatant was measured. The yield of fine fibrous cellulose was determined based on the following formula.
Yield of fine fibrous cellulose (%) = Solid content concentration of supernatant (%) /0.2 × 100

The present embodiment is characterized in that the supernatant yield of the fine fibrous cellulose dispersion after centrifugation is high, that is, the content of coarse fibers in the fibrous cellulose-containing composition is low, and the fine fibrous cellulose dispersion is characterized. By setting the yield of the supernatant after centrifugation in the above range, good coatability can be obtained when blended in a paint.

(Specific ingredient)
<Sugars>
An example of the specific component used in the present invention is a saccharide. The saccharides include monosaccharides or polysaccharides, among which monosaccharides or disaccharides are preferable, and disaccharides are more preferable. Preferred saccharides include those having glucose units or fructose units, and those having glucose units are more preferable. Specific examples include trehalose, maltose, sucrose, lactulose, lactose, cellobiose, glucose, fructose, mannose, galactose, arabinose, xylose, or derivatives thereof, and trehalose derivatives are preferable. In addition, when referred to as a "derivative" in the present specification, in addition to the compound, a compound having an arbitrary substituent introduced therein or a part of the compound may be desorbed or cyclized to the extent that the effect of the present invention is not impaired. It means that it contains a compound, a compound having an acidic group or a basic group introduced therein, or a salt thereof. Examples of the optional substituent include the substituent Z described later. Examples of the derivative in which a substituent is introduced into trehalose include an ester (acylated product), a sulfate ester or a salt thereof, a quaternary cation product or a salt thereof, and the like. When the acyl group of the acylated product is represented by ^{RY CO−, examples of RY} include the alkyl group, hydroxyalkyl group, aryl group, aralkyl group and the like mentioned in the substituent Z described later.
Although the reason why saccharides are effective in the present invention is not clear, the glucose unit of cellulose and the structure of saccharides such as glucose and fructose interact with each other through hydrogen bonds, and fine fibrous cellulose is used. It is presumed to suppress the aggregation of hydrogen.

<Water-soluble compound>
A second example of the specific component used in the present invention is a water-soluble compound. The water-soluble compound used in the present invention is a compound having a functional group capable of forming a hydrogen bond and having a molecular weight of 200 or less. The functional group is preferably a carbonyl group or an amino group. The water-soluble compound is preferably a urea derivative. Specifically, the urea derivative is preferably a compound represented by the following formula (2) or a salt thereof.

R ^{1 to} R ⁴ independently represent a hydrogen atom or a monovalent organic group. As the monovalent organic group, an alkyl group (preferably 1 to 12 carbon atoms, more preferably 1 to 6 carbon atoms, still more preferably 1 to 3; chain or cyclic, linear or branched), alkenyl group. (Preferably 2 to 12 carbon atoms, more preferably 2 to 6; further preferably 2 to 3; chain or cyclic, linear or branched), aryl group (preferably 6 to 22 carbon atoms, 6). ~ 18 is more preferable, 6 to 10 is more preferable), an aralkyl group (carbon number 7 to 23 is preferable, 7 to 19 is more preferable, 7 to 11 is more preferable. The alkylene moiety may be chain-like or cyclic. It may be linear or branched), a carbamoyl group (preferably 1 to 12 carbon atoms, more preferably 1 to 6 carbon atoms, still more preferably 1 to 6 carbon atoms), an acyl group (preferably 2 to 12 carbon atoms, 2 to 6 carbon atoms are more preferable). Preferably, 2 to 3 are more preferable. The alkyl moiety may be chain or cyclic, linear or branched), an aryloyl group (preferably 7 to 23 carbon atoms, more preferably 7 to 19 carbon atoms, and 7 to 11 carbon atoms are preferable. Further preferred). Among them, R ^{1 to} R ⁴ are preferably a hydrogen atom, a methyl group, an ethyl group, a phenyl group, a benzyl group, a hydroxymethyl group, a hydroxyethyl group and a carbamoyl group, and a hydrogen atom is more preferable. Preferably two or more of R ¹ to R ⁴ is a hydrogen atom, more preferably more than three of R ¹ to R ⁴ is a hydrogen atom, that all of R ¹ to R ⁴ is a hydrogen atom Is particularly preferable.

The monovalent organic group may have a substituent Z described later. For example, the above alkyl group may be a hydroxyalkyl group with a hydroxyl group.
R ^{1 to} R ⁴ may be combined with each other to form a ring. When forming the ring, the linking group Y described later may be interposed.

X represents an oxygen atom or a sulfur atom, and an oxygen atom is preferable. However, the oxygen atom or the sulfur atom is replaced with a hydrogen atom or an alkyl group (preferably 1 to 12 carbon atoms, more preferably 1 to 6 carbon atoms, still more preferably 1 to 3 carbon atoms) to form a compound represented by the formula (2). It may have an isourea structure.

When the compound represented by the formula (2) constitutes a salt, the salt is not particularly limited, and examples thereof include hydrochlorides, sulfates, phosphates, nitrates and the like.

The molecular weight of the water-soluble compound is 200 or less, preferably 150 or less, more preferably 100 or less, and particularly preferably 80 or less. It is practical that the lower limit is 40 or more. The molecular weight of the water-soluble compound can be confirmed by mass spectroscopic.

Specific examples of the water-soluble compound include urea, thiourea, biuret, phenylurea, benzylurea, dimethylurea, diethylurea, tetramethylurea, benzorainurea, hydantin, or salts thereof, and among them, urea or its salts. preferable.

The reason why a water-soluble compound having a functional group capable of forming a hydrogen bond and having a molecular weight of 200 or less is effective is not clear, but the glucose unit of cellulose and the water-soluble compound interact with each other particularly via a hydrogen bond. , It is presumed to suppress the aggregation of fine fibrous cellulose.

The water-soluble compound is not particularly limited as long as it is a compound having solubility in water, but can be defined as, for example, a compound that dissolves in ion-exchanged water at 25 ° C. in an amount of 0.5% by mass or more, and dissolves in an amount of 1% by mass or more. It is preferable, and it is more preferable to dissolve 10% by mass or more.

As the substituent Z, an alkyl group (preferably 1 to 24 carbon atoms, more preferably 1 to 12 carbon atoms, further preferably 1 to 6 carbon atoms) and an aralkyl group (preferably 7 to 21 carbon atoms, 7 carbon atoms). ~ 15 is more preferable, carbon number 7 to 11 is more preferable), hydroxyl group, amino group or a salt thereof (carbon number 0 to 24 is preferable, carbon number 0-12 is more preferable, carbon number 0 ~ 6 is further preferable. ), A thiol group, a carboxyl group or a salt thereof, a carbamoyl group or a salt thereof (preferably 1 to 24 carbon atoms, more preferably 1 to 12 carbon atoms, still more preferably 1 to 6 carbon atoms), a sulfamoyl group or a salt thereof (preferably 1 to 24 carbon atoms), a sulfamoyl group or a salt thereof (preferably 1 to 24 carbon atoms, more preferably 1 to 6 carbon atoms). The number of carbon atoms is preferably 0 to 24, more preferably 0 to 12 carbon atoms, still more preferably 0 to 6 carbon atoms), an aryl group (preferably 6 to 22 carbon atoms, more preferably 6 to 18 carbon atoms, and 6 carbon atoms). 10 to 10 is more preferable), acyl group (preferably 2 to 12 carbon atoms, more preferably 2 to 6 carbon atoms, still more preferably 2 or 3 carbon atoms), acyloxy group (preferably 2 to 12 carbon atoms, carbon number of carbon atoms). 2 to 6 are more preferable, carbon number 2 or 3 is more preferable), heterocyclic group (carbon number 2 to 8 is more preferable, carbon number 2 to 5 is more preferable), halogen atom, quaternary ammonium group or the like. Examples thereof include salts (preferably having 3 to 23 carbon atoms, more preferably 3 to 19 carbon atoms, and even more preferably 3 to 11 carbon atoms).

The linking group Y includes an alkylene group (methylene group, ethylene group, propylene group, etc.), an oxygen atom, a sulfur atom, a carbonyl group, a sulfonyl group, a sulfinyl group, an imino group (NR ^L ), and a linking group related to a combination thereof. Can be mentioned. ^RL is a hydrogen atom, a methyl group, an ethyl group, or a propyl group. The number of atoms contained in the linking group Y is preferably 1 or more and 12 or less, and more preferably 1 or more and 6 or less.

The content of the specific component is preferably 600 parts by mass or less, more preferably 400 parts by mass or less, still more preferably 300 parts by mass or less, and 200 parts by mass with respect to 100 parts by mass of fibrous cellulose. It is particularly preferable that the amount is not more than parts by mass. The content of the specific component is preferably 1 part by mass or more, more preferably 5 parts by mass or more, and further preferably 10 parts by mass or more with respect to 100 parts by mass of the fibrous cellulose. , 15 parts by mass or more is particularly preferable. By setting the value to the above lower limit or more, the coatability of the fibrous cellulose-containing composition and, if necessary, the smoothness of the coating film can be achieved at a high level, which is preferable. When the value is not more than the above upper limit, the desired effect can be exhibited without impairing the characteristics and production suitability required for the fibrous cellulose-containing composition, which is preferable.

The specific component may be used alone or in combination of two or more. When two or more kinds are used, the total amount is preferably in the above range.

(resin)
The fibrous cellulose-containing composition of the present invention may further contain a resin such as a thermoplastic resin, a thermosetting resin, or a photocurable resin, for example, in the case of a paint. Examples of the resin include styrene resin, acrylic resin, aromatic polycarbonate resin, aliphatic polycarbonate resin, aromatic polyester resin, aliphatic polyester resin, aliphatic polyolefin resin, cyclic olefin resin, and polyamide. Resin-based resin, polyphenylene ether-based resin, thermoplastic polyimide-based resin, polyacetal-based resin, polysulfone-based resin, amorphous fluororesin, rosin-based resin, nitrocellulose, vinyl chloride-based resin, rubber chloride-based resin, vinyl acetate resin, Examples thereof include phenol resin and epoxy resin, but the present invention is not limited thereto.

In the case of a paint, the content of the resin is preferably 30 parts by mass or more, more preferably 70 parts by mass or more, and 100 parts by mass or more with respect to 1 part by mass of fibrous cellulose. Is particularly preferred. The content of the resin is preferably 500 parts by mass or less, more preferably 300 parts by mass or less, and particularly preferably 200 parts by mass or less with respect to 1 part by mass of the fibrous cellulose. By containing the resin so as to have the above-mentioned content, the effect of the above-mentioned specific component can be suitably exhibited, and the coatability, the smoothness of the coating film, the elastic modulus and the strength can be optimized.

(Hardener)
When the fibrous cellulose-containing composition of the present invention is used as a paint, it is preferable to contain a curing agent. As the curing agent, known ones can be appropriately used, and examples thereof include isocyanate-based curing agents (polyisocyanate and the like), epoxy (oxylan) -based curing agents, oxetane-based curing agents and the like. In the present invention, an isocyanate-based curing agent is particularly preferable.

In the case of a paint, the content of the curing agent is preferably 10 parts by mass or more, more preferably 20 parts by mass or more, and 30 parts by mass or more with respect to 1 part by mass of fibrous cellulose. It is particularly preferable to have. The content of the curing agent is preferably 100 parts by mass or less, more preferably 80 parts by mass or less, and particularly preferably 60 parts by mass or less with respect to 1 part by mass of the fibrous cellulose. .. By containing the curing agent so as to have the above-mentioned content, the effect of the above-mentioned specific component can be suitably exhibited, and the coatability, the smoothness of the coating film, the elastic modulus and the like can be realized.

(Optional ingredient)
The fibrous cellulose-containing composition of the present invention may contain any component other than the above-mentioned components. Optional components include, for example, defoamers, lubricants, UV absorbers, dyes, pigments, stabilizers, surfactants, coupling agents, inorganic layered compounds, inorganic compounds, leveling agents, organic particles, antistatic agents. , Magnetic powder, orientation promoter, plasticizer, preservative, cross-linking agent and the like. Further, organic ions may be added as an optional component.

(Composition containing fibrous cellulose)
When the fibrous cellulose-containing composition is a paint, the content of the fibrous cellulose is preferably 0.05% by mass or more with respect to the solid content in the fibrous cellulose-containing composition, and 0. It is more preferably 1% by mass or more, and further preferably 0.3% by mass or more. The content of the fibrous cellulose is preferably 10% by mass or less, more preferably 5% by mass or less, and further preferably 2% by mass or less.

When the fibrous cellulose-containing composition is used as a thickener, the content of the fibrous cellulose is preferably 0.1% by mass or more with respect to the total amount of the fibrous cellulose-containing composition, and is preferably 1% by mass. % Or more, 5% by mass or more, 10% by mass or more, 20% by mass or more, 30% by mass or more, 40% by mass or more, 50% by mass or more, or 55% by mass or more. The content of the fibrous cellulose is preferably 95% by mass or less, more preferably 90% by mass or less.

In the use of the thickener, the total amount of the fibrous cellulose, the specific component and water is preferably 80% by mass or more, preferably 90% by mass or more, based on the total amount of the fibrous cellulose-containing composition. It is more preferable, and it is particularly preferable that it is 95% by mass or more.

The form of the fibrous cellulose-containing composition of the present invention is not particularly limited, and can exist in various forms such as powder, slurry, and solid. Among them, the fibrous cellulose-containing composition is preferably a slurry, more preferably a high-viscosity slurry. Specifically, the fibrous cellulose-containing composition has a viscosity of 40,000 mPa · s or less measured under the conditions of 23 ° C. and a rotation speed of 3 rpm, where the solid content concentration of the fibrous cellulose is 0.4% by mass. It is more preferably 35,000 mPa · s or less, further preferably 30,000 mPa · s or less, and particularly preferably 25,000 mPa · s or less. As the lower limit value, a slurry of 3,000 mPa · s or more is preferable, a slurry of 5,000 mPa · s or more is more preferable, a slurry of 6,000 mPa · s or more is further preferable, and a slurry of 6,000 mPa · s or more is further preferable. It is particularly preferable that the slurry is 000 mPa · s or more. By setting this viscosity to the above upper limit value or less, good coatability is exhibited and it is preferable. By setting the value to be equal to or higher than the above lower limit, the Young's modulus and strength of the coating film can be optimized, which is preferable.

The viscosity of the fibrous cellulose-containing composition is measured as follows. After diluting the fibrous cellulose-containing composition with ion-exchanged water so that the solid content concentration becomes 0.4% by mass, the mixture is stirred with a disperser at 1500 rpm for 5 minutes. Next, the viscosity of the dispersion liquid thus obtained is measured using a B-type viscometer (analog viscometer T-LVT manufactured by BLOOKFIELD). The measurement condition is a rotation speed of 3 rpm, and the viscosity value 3 minutes after the start of measurement is the viscosity of the dispersion liquid. In addition, the dispersion liquid to be measured is allowed to stand for a whole day and night in an environment of 23 ° C. and a relative humidity of 50% before measurement. The measurement temperature of the viscosity is 23 ° C. Other detailed measurement conditions and the like are based on JISZ8803: 2011. Five samples are prepared for each level, measurement is performed twice for each, a total of 10 times, and the arithmetic mean value is adopted.

The fibrous cellulose-containing composition of the present invention may be a kit in which fine fibrous cellulose and a specific component are combined. For example, both can be provided separately and, if necessary, in combination with other ingredients. In this case, the combination amount and ratio of the fine fibrous cellulose and the specific component are the same as the blending amount and the like in the fibrous cellulose-containing composition.

(Coating film)
The fibrous cellulose-containing composition of the present invention is preferably coated to form a coating film. The thickness of the coating film is not particularly limited, but when considering the usage as a paint, it is preferably 1000 μm or less, more preferably 500 μm or less, further preferably 300 μm or less, and 100 μm or less. It is more preferably present, and particularly preferably 80 μm or less. As the lower limit value, 1 μm or more is preferable, 5 μm or more is more preferable, and 10 μm or more is particularly preferable.

The surface roughness of the coating film (in the present specification, the surface roughness means the arithmetic mean roughness defined in JISB0601: 2013: Ra) is not particularly limited, but the coating film is not particularly limited. When considering applications such as, it is preferable that the smoothness is more excellent. According to the present invention, if necessary, the arithmetic mean roughness (Ra) can be improved, and Ra is preferably 0.2 μm or less, more preferably 0.17 μm or less, and 0.15 μm or less. Is particularly preferable. The lower limit is not particularly limited, but it is practically 0.001 μm or more.

The surface roughness was measured by using an optical interferometry non-contact surface shape measuring instrument (Non-contact surface / layer cross-sectional shape measuring system VertScan2.0, model: R5500GML) manufactured by Ryoka System Co., Ltd., and measuring range 470 with a × 10 objective lens. An arithmetic average roughness (Ra) of 92 μm × 353.16 μm is measured. The measurement is performed 5 times per level, and the arithmetic mean roughness is obtained from the average value. Details of the definition of arithmetic mean roughness (Ra), measurement conditions, calculation method, etc. are based on JISB0601: 2013.

The Young's modulus of the coating film is not particularly limited, but when considering a higher Young's modulus, for example, it is preferably 0.3 GPa or more, more preferably 0.5 GPa or more, and 0.7 GPa or more. Is more preferable, and 0.8 GPa or more is particularly preferable. As an upper limit value, it is practical that it is 8 GPa or less. According to the present invention, since such a high Young's modulus can be achieved, it can be suitably used in applications requiring a high elastic modulus.

The Young's modulus of the coating film was set to JIS P 8113: 2006 using a tensile tester Tencilon (manufactured by A & D Co., Ltd.) except that the length of the test piece between the grips was 50 mm and the tensile speed was 5 mm / min. Measure according to. When measuring Young's modulus, a test piece prepared at 23 ° C. and a relative humidity of 50% for 24 hours is used. The measurement is performed 5 times per level, and the average value is adopted.

(Membrane manufacturing method)
The manufacturing process of the thickener, the paint, the film and the like is not particularly limited.
The thickener mixes a dispersion containing fibrous cellulose having a fiber width of 1000 nm or less (may be in the form of a slurry), a specific component or a solution containing the same, and if necessary, another component (for example, water). It can be manufactured by.
The paint includes fine fibrous cellulose (which may be a dispersion), a specific component (which may be a solution), a resin (for example, an acrylic resin), a curing agent (for example, polyisocyanate), and if necessary, others. It can be produced by mixing with the components of (for example, an organic solvent).
The film can be produced by applying a composition containing fine fibrous cellulose and a specific component (for example, the above-mentioned paint or thickener) to form a coating film. Specifically, for example, a coating film can be formed by a step of applying a composition containing fine fibrous cellulose and a specific component onto a substrate and a step of drying the composition.
The coating film formed above may be peeled off from the base material to form a sheet.
Further, the sheet may be produced by papermaking a composition containing fine fibrous cellulose and a specific component (the above-mentioned paint or thickener may be used).

<Coating process>
The coating step is a step of coating a composition containing fine fibrous cellulose and a specific component (the above-mentioned paint or thickener may be used) on a base material.
When producing a sheet, the sheet can be continuously produced by using a coating device and a long base material.

The material of the base material used in the coating process is not particularly limited, but a material having high wettability to the composition may suppress shrinkage of the sheet during drying, but the sheet formed after drying may be used. It is preferable to select one that can be easily peeled off. Of these, a resin film or plate or a metal film or plate is preferable, but is not particularly limited. For example, resin films and plates such as acrylic, polyethylene terephthalate, vinyl chloride, polystyrene, polypropylene, and polyvinylidene chloride, metal films and plates of aluminum, zinc, copper, and iron plates, and those whose surfaces are oxidized, stainless steel. Films and plates, brass films and plates, etc. can be used.

In the coating process, if the viscosity of the composition to be coated is low and it develops on the substrate, a dammed frame is fixed on the substrate in order to obtain a sheet with a predetermined thickness and basis weight. May be used. The quality of the dammed frame is not particularly limited, but it is preferable to select one in which the end portion of the sheet to be attached after drying can be easily peeled off. Of these, those obtained by molding a resin plate or a metal plate are preferable, but are not particularly limited. For example, resin plates such as acrylic plates, polyethylene terephthalate plates, vinyl chloride plates, polystyrene plates, polypropylene plates and polyvinylidene chloride plates, metal plates such as aluminum plates, zinc plates, copper plates and iron plates, and their surfaces were oxidized. It is possible to use a molded product, a stainless steel plate, a brass plate, or the like.

As the coating machine for coating the composition, for example, an applicator, a roll coater, a gravure coater, a die coater, a curtain coater, an air doctor coater and the like can be used. An applicator, a die coater, a curtain coater, and a spray coater are preferable because the thickness can be made more uniform.

The coating temperature is not particularly limited, but is preferably 20 ° C. or higher and 45 ° C. or lower, more preferably 25 ° C. or higher and 40 ° C. or lower, and further preferably 27 ° C. or higher and 35 ° C. or lower. When the coating temperature is at least the above lower limit value, the composition can be easily coated, and when it is at least the above upper limit value, volatilization of the dispersion medium during coating can be suppressed.

In the coating step, it is preferable to coat the composition so that the finished basis weight of the sheet is 10 g / m ² or more and 100 g / m ² or less, preferably 20 g / m ² or more and 60 g / m ² or less. By coating so that the basis weight is within the above range, a sheet having excellent strength can be obtained.

The coating step preferably includes a step of drying the composition coated on the substrate. The drying method is not particularly limited, and either a non-contact drying method or a method of drying while restraining the sheet may be used, or a combination of these may be used.

The non-contact drying method is not particularly limited, but a method of heating and drying with hot air, infrared rays, far infrared rays or near infrared rays (heat drying method) and a method of vacuum drying (vacuum drying method) are applied. Can be done. The heat drying method and the vacuum drying method may be combined, but usually, the heat drying method is applied. Drying with infrared rays, far infrared rays or near infrared rays can be performed using an infrared device, a far infrared device or a near infrared device, but is not particularly limited. The heating temperature in the heat drying method is not particularly limited, but is preferably 20 ° C. or higher and 150 ° C. or lower, and more preferably 25 ° C. or higher and 105 ° C. or lower. When the heating temperature is at least the above lower limit value, the dispersion medium can be rapidly volatilized, and when it is at least the above upper limit value, the cost required for heating can be suppressed and the discoloration of fine fibrous cellulose can be suppressed by heat. ..

<Papermaking process>
In the case of producing a sheet, the sheet manufacturing process may include a step of making a composition (which may be the above-mentioned paint or thickener) containing fine fibrous cellulose and a specific component. Examples of the paper machine in the paper making process include continuous paper machines such as a long net type, a circular net type, and an inclined type, and a multi-layer paper making machine combining these. In the papermaking process, known papermaking such as hand papermaking may be performed.

In the papermaking process, the composition is filtered on a wire and dehydrated to obtain a wet paper sheet, which is then pressed and dried to obtain a sheet. When the above composition is filtered and dehydrated, the filter cloth at the time of filtration is not particularly limited, but it is important that fine fibrous cellulose and preservatives do not pass through and the filtration rate does not become too slow. The filter cloth is not particularly limited, but a sheet made of an organic polymer, a woven fabric, and a porous membrane are preferable. The organic polymer is not particularly limited, but non-cellulosic organic polymers such as polyethylene terephthalate, polyethylene, polypropylene, and polytetrafluoroethylene (PTFE) are preferable. Specific examples thereof include a porous membrane of polytetrafluoroethylene having a pore size of 0.1 μm or more and 20 μm or less, for example, 1 μm, polyethylene terephthalate having a pore diameter of 0.1 μm or more and 20 μm or less, for example, 1 μm, or a polyethylene woven fabric, but the present invention is not particularly limited.

The method for producing a sheet from the above composition is not particularly limited, and examples thereof include a method using the production apparatus described in WO2011 / 013567. This manufacturing apparatus discharges a composition containing fine fibrous cellulose onto the upper surface of an endless belt, and a watering section that squeezes a dispersion medium from the discharged composition to generate a web, and a watering section that dries the web to produce fibers. It has a drying section to produce the sheet. An endless belt is disposed from the watering section to the drying section, and the web generated in the watering section is conveyed to the drying section while being placed on the endless belt.

The dehydration method that can be adopted is not particularly limited, and examples thereof include a dehydration method that is usually used in paper production, and a method of dehydrating with a long net, a circular net, an inclined wire, or the like and then dehydrating with a roll press is preferable. Further, the drying method is not particularly limited, and examples thereof include methods used in the production of paper, and for example, methods such as a cylinder dryer, a Yankee dryer, hot air drying, a near infrared heater, and an infrared heater are preferable.

(Laminated body)
Another layer may be further laminated on the coating film or sheet obtained in the above-mentioned step to form a laminated body. Such other layers may be provided on both surfaces of the coating film or sheet, but may be provided only on one surface of the coating film or sheet. Examples of the other layer laminated on at least one surface of the coating film or the sheet include a resin layer and an inorganic layer.

Specific examples of the laminate include, for example, a laminate in which a resin layer is directly laminated on at least one surface of a coating film or a sheet, or an inorganic layer is directly laminated on at least one surface of a coating film or a sheet. Laminates, resin layers, coating films or sheets, laminates in which inorganic layers are laminated in this order, coating films or sheets, resin layers, laminates in which inorganic layers are laminated in this order, coating films or sheets, inorganic layers , A laminated body in which resin layers are laminated in this order can be mentioned. The layer structure of the laminated body is not limited to the above, and may be various modes depending on the application.

<Resin layer>
The resin layer is a layer containing a natural resin or a synthetic resin as a main component. Here, the main component refers to a component contained in an amount of 50% by mass or more with respect to the total mass of the resin layer. The content of the resin is preferably 60% by mass or more, more preferably 70% by mass or more, further preferably 80% by mass or more, and 90% by mass, based on the total mass of the resin layer. The above is particularly preferable. The content of the resin may be 100% by mass or 95% by mass or less.

Examples of the natural resin include rosin-based resins such as rosin, rosin ester, and hydrogenated rosin ester.

As the synthetic resin, for example, at least one selected from polycarbonate resin, polyethylene terephthalate resin, polyethylene naphthalate resin, polyethylene resin, polypropylene resin, polyimide resin, polystyrene resin, polyurethane resin and acrylic resin is preferable. Among them, the synthetic resin is preferably at least one selected from the polycarbonate resin and the acrylic resin, and more preferably the polycarbonate resin. The acrylic resin is preferably at least one selected from polyacrylonitrile and poly (meth) acrylate.

Examples of the polycarbonate resin constituting the resin layer include aromatic polycarbonate-based resins and aliphatic polycarbonate-based resins. These specific polycarbonate-based resins are known, and examples thereof include the polycarbonate-based resins described in JP-A-2010-023275.

As the resin constituting the resin layer, one kind may be used alone, or a copolymer obtained by copolymerizing or graft-polymerizing a plurality of resin components may be used. Further, a plurality of resin components may be used as a blend material mixed by a physical process.

An adhesive layer may be provided between the coating film or the sheet and the resin layer, or the adhesive layer may not be provided and the coating film or the sheet and the resin layer may be in direct contact with each other. When an adhesive layer is provided between the coating film or sheet and the resin layer, examples of the adhesive constituting the adhesive layer include acrylic resins. Examples of the adhesive other than the acrylic resin include vinyl chloride resin, (meth) acrylic acid ester resin, styrene / acrylic acid ester copolymer resin, vinyl acetate resin, and vinyl acetate / (meth) acrylic acid ester. Examples include polymer resins, urethane resins, silicone resins, epoxy resins, ethylene / vinyl acetate copolymer resins, polyester resins, polyvinyl alcohol resins, ethylene vinyl alcohol copolymer resins, and rubber emulsions such as SBR and NBR. Be done.

When the adhesive layer is not provided between the coating film or the sheet and the resin layer, the resin layer may have an adhesion aid, and the surface of the resin layer is subjected to surface treatment such as hydrophilization treatment. May be good.
Examples of the adhesion aid include a compound containing at least one selected from an isocyanate group, a carbodiimide group, an epoxy group, an oxazoline group, an amino group and a silanol group, and an organic silicon compound. Among them, the adhesion aid is preferably at least one selected from a compound containing an isocyanate group (isocyanate compound) and an organosilicon compound. Examples of the organosilicon compound include a silane coupling agent condensate and a silane coupling agent.
Examples of the surface treatment method other than the hydrophilization treatment include corona treatment, plasma discharge treatment, UV irradiation treatment, electron beam irradiation treatment, flame treatment and the like.

<Inorganic layer>
The substance constituting the inorganic layer is not particularly limited, and is, for example, aluminum, silicon, magnesium, zinc, tin, nickel, titanium; these oxides, carbides, nitrides, oxide carbides, oxide nitrides, or oxide carbides. Things; or mixtures thereof. From the viewpoint that high moisture resistance can be stably maintained, silicon oxide, silicon nitride, silicon oxide carbide, silicon nitride, silicon oxide, aluminum oxide, aluminum nitride, aluminum oxide, aluminum nitride, or any of these. Mixtures are preferred.

The method for forming the inorganic layer is not particularly limited. Generally, the method for forming a thin film is roughly classified into a chemical vapor deposition (CVD) method and a physical vapor deposition method (PVD), and any method may be adopted. .. Specific examples of the CVD method include plasma CVD using plasma, catalytic chemical vapor deposition (Cat-CVD) for catalytically pyrolyzing a material gas using a heating catalyst, and the like. Specific examples of the PVD method include vacuum deposition, ion plating, sputtering and the like.

Further, as a method for forming the inorganic layer, an atomic layer deposition method (ALD) can also be adopted. The ALD method is a method of forming a thin film in atomic layer units by alternately supplying the raw material gas of each element constituting the film to be formed to the surface on which the layer is formed. Although it has the disadvantage of a slow film formation rate, it has the advantage of being able to cleanly cover even a surface having a complicated shape and forming a thin film with few defects, as compared with the plasma CVD method. Further, the ALD method has an advantage that the film thickness can be controlled on the nano-order and it is relatively easy to cover a wide surface. Furthermore, the ALD method can be expected to improve the reaction rate, make it a low temperature process, and reduce the amount of unreacted gas by using plasma.

(Use)
The cellulose-containing composition of the present invention can be used for various purposes as a thickener.
Further, the fibrous cellulose-containing composition of the present invention may be mixed with, for example, a paint, a resin, an emulsion, a hydraulic material (cement), or rubber and used as a reinforcing material.
Various coating films or sheets may be prepared using the cellulose-containing composition of the present invention.

Sheets are suitable for applications of light transmissive substrates such as various display devices, various solar cells, and the like. It is also suitable for applications such as substrates for electronic devices, materials for home appliances, window materials for various vehicles and buildings, interior materials, exterior materials, and packaging materials. Further, it is suitable for applications such as threads, filters, woven fabrics, cushioning materials, sponges, abrasives, etc., as well as applications in which the sheet itself is used as a reinforcing material.

Hereinafter, the features of the present invention will be described in more detail with reference to Examples and Comparative Examples. The materials, amounts used, ratios, treatment contents, treatment procedures, etc. shown in the following examples can be appropriately changed as long as they do not deviate from the gist of the present invention. Therefore, the scope of the present invention should not be construed as limiting by the specific examples shown below. In the following examples, for convenience of explanation, a slurry treated with fine fibrous cellulose is referred to as a dispersion liquid, and a slurry containing this and a specific component is referred to as a fibrous cellulose-containing composition. A mixture of a fibrous cellulose-containing composition, a resin, a curing agent, or the like is referred to as a paint. However, this does not limit the scope of the present invention. For example, those containing fine fibrous cellulose such as paints, specific components and other components are also included in the scope of the fibrous cellulose-containing composition of the present invention.

<Manufacturing of fine fibrous cellulose dispersion (1)>
(Phosphorylation process)
As raw material pulp, Oji Paper's softwood kraft pulp (solid content 93% by mass, basis weight 208 g / m ² sheet form, separated and measured according to JIS P 811-2: 2012 Canadian standard drainage degree (CSF) ) Used 700 ml). The raw material pulp was subjected to phosphorylation treatment as follows. First, a mixed aqueous solution of ammonium dihydrogen phosphate and urea is added to 100 parts by mass (absolute dry mass) of the raw material pulp to obtain 45 parts by mass of ammonium dihydrogen phosphate, 120 parts by mass of urea, and 150 parts by mass of water. To obtain a chemical-impregnated pulp. Next, the obtained chemical-impregnated pulp was heated in a hot air dryer at 165 ° C. for 200 seconds to introduce a phosphate group into the cellulose in the pulp to obtain a phosphorylated pulp. Then, the obtained phosphorylated pulp was washed. The cleaning treatment is carried out by repeating the operation of pouring 10 L of ion-exchanged water into 100 g (absolute dry mass) of phosphorylated pulp, stirring the pulp dispersion liquid so that the pulp is uniformly dispersed, and then filtering and dehydrating the pulp. gone. When the electrical conductivity of the filtrate became 100 μS / cm or less, the washing end point was set.

Then, the phosphorylated pulp after washing was subjected to alkali treatment as follows. First, the washed phosphorylated pulp was diluted with 10 L of ion-exchanged water, and then a 1N aqueous sodium hydroxide solution was added little by little with stirring to obtain a phosphorylated pulp slurry having a pH of 12 or more and 13 or less. .. Then, the phosphorylated pulp slurry was dehydrated to obtain an alkali-treated phosphorylated pulp.

Next, the phosphorylated pulp after the alkali treatment was subjected to the above cleaning treatment.
The infrared absorption spectrum of the phosphorylated pulp thus obtained was measured using FT-IR. As a result, ^{absorption based on the phosphate group was observed around 1230 cm-1} , and it was confirmed that the phosphate group was added to the pulp. The amount of phosphoric acid group (strong acid group amount) measured by the measuring method described later was 1.45 mmol / g.
Further, when the obtained phosphorylated pulp was tested and analyzed by an X-ray diffractometer, it was found at two positions, 2θ = 14 ° or more and 17 ° or less and 2θ = 22 ° or more and 23 ° or less. A typical peak was confirmed, and it was confirmed that it had cellulose type I crystals.

(Defibration treatment)
Ion-exchanged water was added to the obtained phosphorylated pulp to prepare a slurry having a solid content concentration of 2% by mass. This slurry was treated three times with a wet atomizer (Sugino Machine Limited, Starburst) at a pressure of 200 MPa to obtain a fine fibrous cellulose dispersion liquid (1) containing fine fibrous cellulose. By X-ray diffraction, it was confirmed that this fine fibrous cellulose maintained the cellulose type I crystal. Moreover, when the fiber width of the fine fibrous cellulose was measured using a transmission electron microscope according to the following measuring method, it was 3 to 5 nm.
The 0.4% by mass viscosity of the fine fibrous cellulose was measured and found to be 22400 [mPa · s].

<Measurement of fiber width>
The fiber width of the fine fibrous cellulose was measured by the following method.
The supernatant of the fine fibrous cellulose dispersion obtained by treatment with a wet atomizing device is mixed with water so that the concentration of the fine fibrous cellulose is 0.01% by mass or more and 0.1% by mass or less. It was diluted and added dropwise to the hydrophilized carbon grid film. After drying this, it was stained with uranyl acetate and observed with a transmission electron microscope (JEOL-2000EX, manufactured by JEOL Ltd.).

<Manufacturing of fine fibrous cellulose dispersion (2)>
(TEMPO oxidation process)
As the raw material pulp, softwood kraft pulp (undried) made by Oji Paper was used. The raw material pulp was subjected to alkaline TEMPO oxidation treatment as follows. First, the above-mentioned raw material pulp equivalent to 100 parts by mass of dry mass, 1.6 parts by mass of TEMPO (2,2,6,6-tetramethylpiperidin-1-oxyl), and 10 parts by mass of sodium bromide are added to 10,000 parts by mass of water. It was dispersed in the department. Then, a 13 mass% sodium hypochlorite aqueous solution was added to 1.0 g of pulp so as to be 3.8 mmol, and the reaction was started. During the reaction, a 0.5 M aqueous sodium hydroxide solution was added dropwise to keep the pH at 10 or more and 10.5 or less, and the reaction was considered to be completed when no change was observed in the pH.

Then, the obtained TEMPO oxide pulp was washed. The washing treatment is carried out by dehydrating the pulp slurry after TEMPO oxidation to obtain a dehydrated sheet, pouring 5000 parts by mass of ion-exchanged water, stirring and uniformly dispersing the pulp slurry, and then repeating the operation of filtering and dehydrating. rice field. When the electrical conductivity of the filtrate became 100 μS / cm or less, the washing end point was set.

The dehydrated sheet was subjected to additional oxidation treatment of the remaining aldehyde groups as follows. The dehydration sheet corresponding to 100 parts by mass of dry mass was dispersed in 10000 parts by mass of 0.1 mol / L acetate buffer (pH 4.8). Then, 113 parts by mass of 80% sodium chlorite was added, and the mixture was immediately sealed, and then reacted at room temperature for 48 hours while stirring at 500 rpm using a magnetic stirrer to obtain a pulp slurry.
Then, the obtained top-oxidized TEMPO oxide pulp was washed. The washing treatment is carried out by dehydrating the pulp slurry after additional oxidation to obtain a dehydrated sheet, pouring 5000 parts by mass of ion-exchanged water, stirring and uniformly dispersing the pulp slurry, and then repeating the operation of filtration and dehydration. rice field. When the electrical conductivity of the filtrate became 100 μS / cm or less, the washing end point was set.

With respect to the TEMPO oxide pulp thus obtained, the amount of carboxyl groups measured by the measuring method described later was 1.30 mmol / g.
Further, when the obtained TEMPO oxide pulp was tested and analyzed by an X-ray diffractometer, it was found at two positions, 2θ = 14 ° or more and 17 ° or less and 2θ = 22 ° or more and 23 ° or less. A typical peak was confirmed, and it was confirmed that it had cellulose type I crystals.

(Defibration treatment)
Ion-exchanged water was added to the obtained phosphorylated pulp to prepare a slurry having a solid content concentration of 2% by mass. This slurry was treated with a wet atomizing device (manufactured by Sugino Machine Limited, Starburst) 6 times at a pressure of 200 MPa to obtain a fine fibrous cellulose dispersion liquid (2) containing fine fibrous cellulose. By X-ray diffraction, it was confirmed that this fine fibrous cellulose maintained the cellulose type I crystal. Moreover, when the fiber width of the fine fibrous cellulose was measured using a transmission electron microscope, it was 3 to 5 nm.
The 0.4% by mass viscosity of the fine fibrous cellulose was measured and found to be 11000 [mPa · s].

<Manufacturing of fine fibrous cellulose dispersion (3)>
Fine fibrous cellulose dispersion (1), the fine relative fibrous cellulose 1 part by weight, enzyme-containing liquid (AB Enzymes, Inc., ECOPULP R, enzyme content is approximately 5 wt%) to 3.0 × 10 ^{- 6} parts by mass was added, and the mixture was stirred at 18,500 rpm for 2 minutes. This was recovered to obtain a fine fibrous cellulose dispersion (3). The fine fibrous cellulose dispersion (3) contains an enzyme.
The 0.4% by mass viscosity of the fine fibrous cellulose was measured and found to be 9000 [mPa · s].

<Manufacturing of fine fibrous cellulose dispersion A>
A fine fibrous cellulose dispersion liquid in the same manner as the fine fibrous cellulose dispersion liquid (2) except that the number of treatments at a pressure of 200 MPa using a wet atomization device (Sugino Machine Limited, Starburst) was set to 3 times. I got A.
The 0.4% by mass viscosity of the fine fibrous cellulose was measured and found to be 20400 [mPa · s].

The physical characteristics of each fine fibrous cellulose were measured according to the following procedure. The results are shown in Table 1 above.

<Measurement of phosphate group amount>
The amount of phosphoric acid group of the fine fibrous cellulose is a fibrous form prepared by diluting the fine fibrous cellulose dispersion containing the target fine fibrous cellulose with ion-exchanged water so that the content is 0.2% by mass. The cellulose-containing slurry was treated with an ion-exchange resin and then titrated with an alkali for measurement.
For the treatment with the ion exchange resin, a strongly acidic ion exchange resin (Amberjet 1024; Organo Corporation, conditioned) with a volume of 1/10 is added to the above fibrous cellulose-containing slurry, and the mixture is shaken for 1 hour. This was done by pouring onto a mesh with an opening of 90 μm to separate the resin and the slurry.
For titration using alkali, a 0.1 N sodium hydroxide aqueous solution is added to the fibrous cellulose-containing slurry treated with an ion exchange resin once every 30 seconds by 50 μL, and the electrical conductivity shown by the slurry is shown. This was done by measuring the change in the value of. For the amount of phosphoric acid group (mmol / g), the amount of alkali (mmol) required in the region corresponding to the first region shown in FIG. 1 of the measurement results is divided by the solid content (g) in the slurry to be titrated. Calculated.

<Measurement of carboxyl group amount>
The amount of carboxyl group of the fine fibrous cellulose is a fibrous cellulose prepared by diluting the fine fibrous cellulose dispersion containing the target fine fibrous cellulose with ion-exchanged water so that the content is 0.2% by mass. The contained slurry was treated with an ion exchange resin and then titrated with an alkali for measurement.
For the treatment with the ion exchange resin, a strongly acidic ion exchange resin (Amberjet 1024; Organo Corporation, conditioned) with a volume of 1/10 is added to the above fibrous cellulose-containing slurry, and the mixture is shaken for 1 hour. This was done by pouring onto a mesh with an opening of 90 μm to separate the resin and the slurry.
In the titration using alkali, 50 μL of 0.1 N sodium hydroxide aqueous solution is added to the fibrous cellulose-containing slurry treated with an ion exchange resin once every 30 seconds to obtain the electrical conductivity of the slurry. This was done by measuring the change in value. For the amount of carboxyl group (mmol / g), the amount of alkali (mmol) required in the region corresponding to the first region shown in FIG. 2 of the measurement results is divided by the solid content (g) in the slurry to be titrated. Calculated.

<Measurement of viscosity of fine fibrous cellulose dispersion>
The viscosity of the fine fibrous cellulose dispersion was measured as follows. First, the fine fibrous cellulose dispersion was diluted with ion-exchanged water so that the solid content concentration was 0.4% by mass, and then stirred with a disperser at 1500 rpm for 5 minutes. Then, the viscosity of the dispersion liquid thus obtained was measured using a B-type viscometer (analog viscometer T-LVT manufactured by BLOOKFIELD). The measurement conditions were a rotation speed of 3 rpm, and the viscosity value 3 minutes after the start of the measurement was taken as the viscosity of the dispersion. The dispersion to be measured was allowed to stand in an environment of 23 ° C. and a relative humidity of 50% for a whole day and night before the measurement. The measurement temperature of the viscosity was 23 ° C. Other detailed measurement conditions and the like were based on JISZ8803: 2011. Five samples were prepared for each level, and measurements were performed twice each, for a total of 10 times, and the arithmetic mean value was adopted.

<Measurement of supernatant yield after centrifugation of fine fibrous cellulose dispersion>
The supernatant yield after centrifuging the fine fibrous cellulose dispersion was measured by the method described below. The yield of the supernatant after centrifugation is an index of the yield of the fine fibrous cellulose, and the higher the yield of the supernatant, the higher the yield of the fine fibrous cellulose.
The fine fibrous cellulose dispersion was adjusted to a solid content concentration of 0.2% by mass, and centrifuged at 12000 G for 10 minutes using a cooling high-speed centrifuge (Kokusan Co., Ltd., H-2000B). The obtained supernatant was collected, and the solid content concentration of the supernatant was measured. The yield of fine fibrous cellulose was determined based on the following formula.
Supernatant yield (%) = supernatant solid content concentration (%) /0.2 × 100
Five samples were prepared for each level, two measurements were taken each, for a total of ten measurements, and the arithmetic mean value was adopted.

<Example 1>
(Preparation of fibrous cellulose-containing composition)
Ion-exchanged water was added to trehalose (manufactured by Wako Pure Chemical Industries, Ltd.) to prepare an aqueous solution having a solid content concentration of 2% by mass.
100 g of the fine fibrous cellulose dispersion (1) having a solid content concentration of 2% by mass was placed in a beaker, and 360 g of ion-exchanged water and 40 g of a 2% by mass trehalose aqueous solution were added thereto. Addition is T.I. K. After stirring with a homodisper (manufactured by Tokushu Kagaku Kogyo) at 1500 rpm and stirring for another 5 minutes after adding trehalose, defoaming with a defoaming device (manufactured by Shinky Co., Ltd., rotation / revolution mixer AR-250). Processing was performed.
As a result, the fibrous cellulose-containing composition has a solid content concentration of 0.4% by mass of the fine fibrous cellulose, a solid content concentration of trehalose of 0.16%, and a fine fibrous cellulose to trehalose 100: 40 (mass ratio). Got

(Measurement of viscosity of fibrous cellulose-containing composition)
The viscosity of the obtained fibrous cellulose-containing composition was measured by using a B-type viscometer (BLOOKFIELD, analog viscometer T-LVT) after allowing it to stand in an environment of 23 ° C. and a relative humidity of 50% for a whole day and night. did. The measurement conditions were a rotation speed of 3 rpm, and the viscosity value 3 minutes after the start of the measurement was taken as the viscosity of the dispersion. The measurement temperature of the viscosity was 23 ° C. Other detailed measurement conditions and the like were based on JISZ8803: 2011. Five samples were prepared for each level, and measurements were performed twice each, for a total of 10 times, and the arithmetic mean value was adopted.

(Preparation of paint)
Weighing 24.8 g of the obtained fibrous cellulose-containing composition into a beaker, 34.6 g of ion-exchanged water, 35.1 g of acrylic resin (DIC Corporation, product name: Barnock WD-551, solid content concentration 44.1%), A curing agent (manufactured by DIC Corporation, product name: Barnock DNW-5500, polyisocyanate, solid content concentration 79.8%) was added in the order of 5.5 g. Addition is T.I. K. Stir at 1500 rpm with Homo Disper (manufactured by Tokushu Kagaku Kogyo), and after adding all, stir for another 5 minutes, and then defoam with a defoaming device (manufactured by Shinky Co., Ltd., rotation / revolution mixer AR-250). Processing was performed.
In this way, the solid content ratio acrylic resin: 78, the curing agent: 22, fine fibrous cellulose: 0.5, trehalose: 0.2 (mass ratio), and the total solid content concentration is 20% by mass. Obtained evaluation paint.

<Example 2>
An evaluation paint was obtained in the same manner as in Example 1 except that a 2% by mass aqueous solution of urea (manufactured by Wako Pure Chemical Industries, Ltd.) was used instead of trehalose.

<Example 3>
An evaluation paint was obtained in the same manner as in Example 1 except that the fine fibrous cellulose dispersion liquid (2) was used.

<Example 4>
An evaluation paint was obtained in the same manner as in Example 1 except that the fine fibrous cellulose dispersion liquid (3) was used. The fibrous cellulose-containing composition of Example 4 contains an enzyme.

<Example 5>
The solid content ratio of fine fibrous cellulose to trehalose in the fibrous cellulose-containing composition was 100: 20 (mass ratio), and the amount taken in the preparation of the paint was 24.9 g of the fibrous cellulose-containing composition and ion-exchanged water 34. An evaluation paint was obtained in the same manner as in Example 1 except that 5 g and 35.2 g of acrylic resin were used.
(The solid content ratio of the obtained evaluation paint is acrylic resin: 78, curing agent: 22, fine fibrous cellulose: 0.5, trehalose: 0.1 (mass ratio).)

<Example 6>
The solid content ratio of fine fibrous cellulose to trehalose in the fibrous cellulose-containing composition was 100 to 160 (mass ratio), and the amount taken in the paint preparation was 24.7 g of water dispersion, 35 g of ion-exchanged water, and acrylic resin. An evaluation paint was obtained in the same manner as in Example 1 except that the amount was 34.9 g and the amount of the curing agent was 5.4 g.
(The solid content ratio of the obtained evaluation coating amount is acrylic resin: 78, curing agent: 22, fine fibrous cellulose: 0.5, trehalose: 0.8 (mass ratio).)

<Example 7>
An evaluation paint was obtained in the same manner as in Example 5 except that a 2% by mass aqueous solution of urea (manufactured by Wako Pure Chemical Industries, Ltd.) was used instead of trehalose.
(The solid content ratio of the obtained evaluation paint is acrylic resin: 78, curing agent: 22, fine fibrous cellulose: 0.5, urea: 0.1 (mass ratio).)

<Example 8>
An evaluation paint was obtained in the same manner as in Example 6 except that a 2% by mass aqueous solution of urea (manufactured by Wako Pure Chemical Industries, Ltd.) was used instead of trehalose.
(The solid content ratio of the obtained evaluation coating amount is acrylic resin: 78, curing agent: 22, fine fibrous cellulose: 0.5, urea: 0.8 (mass ratio).)

<Comparative Example 1>
24.9 g of the fine fibrous cellulose dispersion (1) having a solid content concentration of 0.4% by mass was placed in a beaker, and 34.4 g of ion-exchanged water, 35.2 g of acrylic resin, and 5.5 g of a curing agent were added in this order. Addition is T.I. K. Perform with stirring at 1500 rpm with a homodisper (manufactured by Tokushu Kagaku Kogyo), add all, stir for another 5 minutes, and then remove with a defoaming device (manufactured by Shinky, rotation / revolution mixer AR-250). Foam treatment was performed.
In this way, an evaluation paint having a solid content ratio of acrylic resin: 78, a curing agent: 22, and fine fibrous cellulose: 0.5 (mass ratio) was obtained.

<Comparative Example 2>
An evaluation paint was obtained in the same manner as in Comparative Example 1 except that the fine fibrous cellulose dispersion A was used.

<Reference example>
No fine fibrous cellulose dispersion was added, and the amount taken in the paint preparation was 35.2 g of acrylic resin, 34.4 g of ion-exchanged water, and 5.5 g of curing agent. Similarly, an evaluation paint was obtained.
(The solid content ratio of the obtained evaluation coating amount is acrylic resin: 78, curing agent: 22 (mass ratio)).

The physical characteristics of each of the paints prepared above and the cured coating film thereof were evaluated. The evaluation results are shown in Table 2 below. The measurement conditions for each evaluation item will be described later.

From the above results, it can be seen that the fibrous cellulose-containing composition of the present invention has excellent coatability when used as a paint (Examples 1 to 8), and there are few foreign substances in the film after coating. Further, it can be seen that by using the fibrous cellulose-containing composition of the present invention, the surface of the coating film can be smoothed, if necessary, and the Young's modulus and strength of the coating film suitable for practical use can be realized. On the other hand, in the fibrous cellulose-containing compositions (Comparative Examples 1 and 2) containing no specific component according to the present invention, the coatability was inferior and the surface of the coating film became rough.

(Creation of coating film for appearance evaluation)
Using the obtained paint, PET (polyethylene terephthalate) film (manufactured by Toray Industries, Inc., product name: Lumirror T60, thickness 75 μm) is used as a base material, and the coating film is coated at room temperature so that the coating film thickness after drying is 30 μm using an applicator. did. Immediately after coating, the mixture was heated in a dryer at a temperature of 80 ° C. for 30 minutes to obtain a coated product of a cured coating film using a PET film as a base material. The thickness of the coating film was measured with a stylus type thickness gauge (Millitron 1202D manufactured by Marl Co., Ltd.), and an arithmetic average value of 20 points was adopted. Details of other measurement conditions, calculation methods, etc. were based on JIS P8118: 2014.

(Surface roughness)
Using a light interference type non-contact surface shape measuring device (Non-contact surface / layer cross-sectional shape measuring system VertScan2.0, model: R5500GML), measuring range 470.92 μm × 353.16 μm with × 10 objective lens The arithmetic mean roughness (Ra) of was measured. The measurement was performed 5 times per level, and the arithmetic mean roughness was obtained from the average value. Details of the definition of arithmetic mean roughness (Ra), measurement conditions, calculation method, etc. were based on JISB0601: 2013.

(Evaluation of coatability)
Performs observation of the coating prepared by the base PET film using an optical microscope (manufactured by Nikon Corporation), confirmed over 5μm during 1 mm ² in size of the aggregates number N (the number / mm ²⁾ at 20 sites Then, the arithmetic mean value (N / 20) was calculated. The measurement was performed 5 times per level and the average value was adopted. The numerical values (pieces / mm ² ) are shown in the table, and the results are evaluated by distinguishing them as follows.
There are 3 grains with a size of 5 μm or more / mm ² or more: ×
3 grains with a size of 5 μm or more / ^{less than 2} mm 2 or none: ○
The size of the particles was the diameter equivalent to a circle, and the details of the measurement conditions, calculation method, etc. were based on JISZ8827-1: 2008.

(Creation of coating film for evaluation of strength and Young's modulus)
It was prepared in the same manner as the test piece prepared in "Preparation of coating film for appearance evaluation" except that a PP (polypropylene) film (manufactured by Toray Industries, Inc., product name: Trefan BO, thickness 60 μm) was used as a base material.
The prepared coating film was peeled off from the PP film and used as a sample for strength and Young's modulus evaluation.

(Young's modulus of the coating film)
Young's modulus was calculated using a tensile tester Tencilon (manufactured by A & D Co., Ltd.) in accordance with JIS P 8113: 2006 except that the length of the test piece was 80 mm and the distance between chucks was 50 mm. When measuring Young's modulus, a test piece prepared at 23 ° C. and a relative humidity of 50% for 24 hours was used. The measurement was performed 5 times per level, and the average value was adopted.

(Strength of coating film)
The strength (tensile strength) of the coating film prepared using the fibrous cellulose-containing composition of the reference example was used as the base strength. The testing machine, test conditions, and conforming standards at this time were the same as those for the above-mentioned Young's modulus measurement. The test pieces of Examples and Comparative Examples were similarly tested, and those having a strength (tensile strength) increased by 20% or more from the base strength were designated as “◯”. Those with 10% or more and less than 20% were designated as "Δ", and those with less than 10% were designated as "x". The measurement was performed 5 times per level, and the average value was adopted.

Claims (13)

(A) Fibrous cellulose having a fiber width of 1000 nm or less and
(B) A water-soluble compound or saccharide having a functional group capable of forming a hydrogen bond and having a molecular weight of 200 or less.
A fibrous cellulose-containing composition comprising and further comprising an enzyme. The fibrous cellulose according to claim 1, wherein the content of the water-soluble compound or saccharide having a functional group capable of forming a hydrogen bond and having a molecular weight of 200 or less is 1 part by mass or more with respect to 100 parts by mass of the fibrous cellulose. Containing composition. The fibrous cellulose-containing composition according to claim 1 or 2, wherein the functional group is a carbonyl group or an amino group. The fibrous cellulose-containing composition according to any one of claims 1 to 3 , wherein the surface roughness Ra of the coating film obtained under the following conditions is 0.20 μm or less.
(conditions)
A coating obtained by mixing the fibrous cellulose-containing composition, 156 parts by mass of an acrylic resin with respect to 1 part by mass of the fibrous cellulose, and 44 parts by mass of polyisocyanate with respect to 1 part by mass of the fibrous cellulose. The liquid is applied to a smooth polyethylene terephthalate plate to a thickness of 30 μm using an applicator, and immediately after the application, it is dried at 80 ° C. for 30 minutes. The fibrous cellulose-containing composition according to any one of claims 1 to 4 , wherein the total amount of the fibrous cellulose, the saccharide or the water-soluble compound and water is 90% by mass or more with respect to the entire composition. .. The fibrous cellulose-containing composition according to any one of claims 1 to 5 , wherein the content of the saccharide or the water-soluble compound is 10 parts by mass or more with respect to 100 parts by mass of the fibrous cellulose. The fiber according to any one of claims 1 to 6 , wherein the viscosity measured under the conditions of 23 ° C. and 3 rpm, where the solid content concentration of the fibrous cellulose is 0.4% by mass, is 40,000 mPa · s or less. Cellulose-containing composition. The fibrous cellulose-containing product according to any one of claims 1 to 7 , wherein the fibrous cellulose is used as a dispersion liquid, and the supernatant yield when the supernatant separated from the dispersion liquid under the following conditions is recovered is 80% by mass or more. Composition.
(conditions)
The dispersion of fibrous cellulose is adjusted to a solid content concentration of 0.2% by mass, and centrifuged at 12000 G for 10 minutes using a cooling high-speed centrifuge. The obtained supernatant was collected, and the solid content concentration of the supernatant was measured. The yield of fibrous cellulose is determined based on the following formula.
Supernatant yield (%) = supernatant solid content concentration (%) /0.2 × 100 The fibrous cellulose-containing composition according to any one of claims 1 to 8 , wherein the Young's modulus of the coating film obtained under the following conditions is 0.7 GPa or more.
(conditions)
A coating obtained by mixing the fibrous cellulose-containing composition, 156 parts by mass of an acrylic resin with respect to 1 part by mass of the fibrous cellulose, and 44 parts by mass of polypropylene with respect to 1 part by mass of the fibrous cellulose. The liquid is applied to a smooth polypropylene plate to a thickness of 30 μm using an applicator, and immediately after the application, it is dried at 80 ° C. for 30 minutes. The fibrous cellulose-containing composition according to any one of claims 1 to 9 for use in paints. The fibrous cellulose-containing composition according to any one of claims 1 to 9 for use in a thickener. A coating material containing the fibrous cellulose-containing composition according to any one of claims 1 to 11. A kit for a fibrous cellulose-containing composition, which is a combination of fibrous cellulose having a fiber width of 1000 nm or less, a water-soluble compound or saccharide having a molecular weight of 200 or less having a functional group capable of forming a hydrogen bond, and an enzyme.

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