Cellulose-containing composition, method for producing same, and method for adjusting viscosity

Abstract

A composition comprising cellulose and a thickening agent, the cellulose comprising oxidized cellulose and / or nanocellulose, the oxidized cellulose being an oxide of a cellulose-based raw material obtained from hypochlorous acid or a salt thereof, and substantially not comprising an N-oxy compound, the nanocellulose being a defibrated product of the oxidized cellulose, the composition being characterized in that the oxidized cellulose is an oxide of a cellulose-based raw material obtained from hypochlorous acid or a salt thereof, and the nanocellulose being a defibrated product of the oxidized cellulose.

Description

TECHNICAL FIELD

[0001] The present application relates to a cellulose-containing composition and a method for producing the same, and a viscosity adjustment method. BACKGROUND

[0002] Various techniques have been proposed for producing a nanocellulose material by oxidizing various cellulose-based raw materials with an oxidizing agent and finely dividing the resulting oxidized cellulose.

[0003] For example, Patent Literature 1 discloses a method for producing cellulose nanofibers, which has a step of producing oxidized cellulose by oxidizing a cellulose-based raw material with hypochlorous acid or a salt thereof having an effective chlorine concentration of 14 to 43 mass%, and a step of nanofibrillating the oxidized cellulose. In addition, Patent Literature 2 discloses a method for producing oxidized cellulose, which uses hypochlorous acid or a salt thereof having an effective chlorine concentration of 6 mass% to 14 mass%, and performs an oxidation reaction on a cellulose-based raw material while adjusting the pH to a range of 5.0 to 14.0. In these methods, since the oxidation treatment is performed without using an N-oxyl compound such as 2,2,6,6-tetramethyl-1-piperidine-N-oxyl (TEMPO), the N-oxyl compound is not left in the cellulose fibers, and thus it is possible to reduce the impact on the environment and the like.

[0004] Patent Literature 3 discloses an oxidized cellulose, which is an oxide of a cellulose-based raw material obtained from hypochlorous acid or a salt thereof, and which substantially does not contain an N-oxyl compound and has a degree of polymerization of 600 or less.

[0005] Patent Literature 4 discloses a nanocellulose, which is a nanocellulose having an average fiber width of 1 nm or more and 200 nm or less, which belongs to an oxide of a cellulose-based raw material obtained from hypochlorous acid or a salt thereof, and which substantially does not contain an N-oxyl compound and has a Zeta potential of -30 mV or less.

[0006] Prior Art Documents

[0007] Patent Literature

[0008] Patent Literature 1: International Publication No. 2018 / 230354

[0009] Patent Literature 2: International Publication No. 2020 / 027307

[0010] Patent Literature 3: International Publication No. 2022 / 009979

[0011] Patent Literature 4: International Publication No. 2022 / 009980 SUMMARY

[0012] PROBLEMS TO BE SOLVED BY THE INVENTION

[0013] An object of the present application is to provide a composition containing oxidized cellulose which is an oxide of a cellulose-based raw material obtained from hypochlorous acid or a salt thereof and / or nanocellulose which is a defibrillated product of the oxidized cellulose, and the viscosity of which can be appropriately adjusted (or adjusted).

[0014] Solution to the problem

[0015] The present inventors have found that if a dispersion liquid containing oxidized cellulose which is an oxide of a cellulose-based raw material obtained from hypochlorous acid or a salt thereof and / or nanocellulose which is a defibrillated product of the oxidized cellulose is mixed with a thickening agent, the viscosity significantly increases.

[0016] The present application includes the following embodiments.

[0017] [1] A composition containing cellulose and a thickening agent,

[0018] The cellulose contains oxidized cellulose which is an oxide of a cellulose-based raw material obtained from hypochlorous acid or a salt thereof and / or nanocellulose which is a defibrillated product of the oxidized cellulose, and substantially does not contain an N-oxyl compound.

[0019] [2] A composition containing cellulose and a thickening agent,

[0020] The cellulose contains oxidized cellulose which has a structure in which the hydroxyl groups at the 2nd and 3rd positions of a glucopyranose ring are oxidized to introduce dicarboxyl groups and / or nanocellulose which is a defibrillated product of the oxidized cellulose.

[0021] [3] The composition according to [1] or [2], wherein the thickening agent is a thickening polysaccharide.

[0022] [4] The composition according to any one of [1] to [3], wherein the thickening agent has a hydrophobic region capable of hydrophobic interaction with the oxidized cellulose.

[0023] [5] The composition according to any one of [1] to [4], wherein the amount of the thickening agent is 0.1 to 40 mass% relative to the mass (solid content) of the oxidized cellulose.

[0024] [6] The composition according to any one of [1] to [5], further containing a salt.

[0025] [7] The composition according to [6], wherein the amount of the salt is 0.01 to 10 mass% relative to the composition.

[0026] [8] The composition according to any one of [1] to [7], further comprising a pH adjustor.

[0027] [9] The composition according to [8], wherein the pH of the composition is in a range of 0 or more and 14.0 or less.

[0028]

[10] The composition according to [8] or [9], wherein the pH adjustor comprises an acid or a base.

[0029]

[11] The composition according to any one of [1] to

[10] , wherein the cellulose comprises the nanocellulose.

[0030]

[12] The composition according to any one of [1] to

[11] , wherein the composition is an aqueous composition.

[0031]

[13] The composition according to

[12] , wherein the viscosity of the aqueous composition is in a range of 0.01 to 1000 Pa-s.

[0032]

[14] The composition according to

[12] or

[14] , wherein the viscosity of the aqueous composition is higher than the viscosity of a control composition obtained by removing the thickening agent from the aqueous composition by 10 to 1 x 10 6 .

[0033]

[15] A composition comprising cellulose and a thickening agent,

[0034] the cellulose comprising oxidized cellulose and / or nanocellulose and substantially not containing an N-oxyl compound, the oxidized cellulose being an oxide of a cellulose-based raw material obtained by hypochlorous acid or a salt thereof, the nanocellulose being a defibrillated product of the oxidized cellulose,

[0035] the pH of the composition being in a range of 0 or more and 14.0 or less.

[0036]

[16] A composition comprising cellulose and a thickening agent,

[0037] the cellulose comprising oxidized cellulose and / or nanocellulose, the oxidized cellulose having a structure in which hydroxyl groups at positions 2 and 3 of a glucopyranose ring are oxidized to introduce dicarboxyl groups, the nanocellulose being a defibrillated product of the oxidized cellulose,

[0038] the pH of the composition being in a range of 0 or more and 14.0 or less.

[0039]

[17] The composition according to any one of [1] to

[16] , wherein the composition is a cosmetic.

[0040]

[18] A method for producing a composition, comprising a step of mixing cellulose with a thickening agent,

[0041] The cellulose contains oxidized cellulose which is an oxidized product of a cellulose-based raw material obtained from hypochlorous acid or a salt thereof, and / or nanocellulose which is a defibrillated product of the oxidized cellulose, and substantially does not contain an N-oxyl compound.

[0042]

[19] A method for producing a composition, comprising a step of mixing cellulose with a thickening agent,

[0043] The cellulose contains oxidized cellulose which has a structure in which hydroxyl groups at positions 2 and 3 of a glucopyranose ring are oxidized to introduce dicarboxyl groups, and / or nanocellulose which is a defibrillated product of the oxidized cellulose.

[0044]

[20] A method for adjusting the viscosity of an aqueous composition containing cellulose, comprising a step of mixing the aqueous composition with a thickening agent,

[0045] The cellulose contains oxidized cellulose which is an oxidized product of a cellulose-based raw material obtained from hypochlorous acid or a salt thereof, and / or nanocellulose which is a defibrillated product of the oxidized cellulose, and substantially does not contain an N-oxyl compound.

[0046]

[21] A method for adjusting the viscosity of an aqueous composition containing cellulose, comprising a step of mixing the aqueous composition with a thickening agent,

[0047] The cellulose contains oxidized cellulose which has a structure in which hydroxyl groups at positions 2 and 3 of a glucopyranose ring are oxidized to introduce dicarboxyl groups, and / or nanocellulose which is a defibrillated product of the oxidized cellulose.

[0048]

[22] The method according to

[20] or

[21] , wherein the viscosity of the aqueous composition is increased by 10 to 1 x 10 6 % by mixing the aqueous composition with the thickening agent.

[0049] Effects of the Invention

[0050] The present application can provide a composition containing oxidized cellulose which belongs to an oxidized product of a cellulose-based raw material obtained from hypochlorous acid or a salt thereof, and / or nanocellulose which belongs to a defibrillated product of the oxidized cellulose, and the viscosity of which can be appropriately adjusted (or adjusted). BRIEF DESCRIPTION OF DRAWINGS

[0051] Figure 1Viscosities of various CNFs, and of mixtures of the CNFs with methyl cellulose (10 mass% relative to the mass of the CNF).

[0052] Figure 2 Viscosities of various CNFs, and of mixtures of the CNFs with methyl cellulose (2 mass% relative to the mass of the CNF).

[0053] Figure 3 Viscosities of various CNFs, and of mixtures of the CNFs with methyl cellulose (10 mass% relative to the mass of the CNF).

[0054] Figure 4 Viscosities of various CNFs, and of mixtures of the CNFs with methyl cellulose (2 mass% relative to the mass of the CNF).

[0055] Figure 5 Viscosities of emulsions containing acrylic resins, and of mixtures of the emulsions with CNF and / or methyl cellulose.

[0056] Figure 6 Viscosities of CNF, mixtures of CNF with methyl cellulose (1.4 mass%, 7.1 mass% and 14 mass% relative to the mass of the CNF), mixtures of CNF with guar gum (1.4 mass%, 7.1 mass% and 14 mass% relative to the mass of the CNF).

[0057] Figure 7 Viscosities of compositions with varying salt concentrations (Example 5 and Comparative Example 4).

[0058] Figure 8 Viscosities of compositions with varying salt concentrations (Example 5 and Comparative Example 5).

[0059] Figure 9 Viscosities of compositions with varying salt concentrations (Example 5 and Comparative Example 6).

[0060] Figure 10 Viscosities of compositions with varying salt concentrations (Example 5 and Comparative Example 7).

[0061] Figure 11 Relationships between pH and viscosity of each of the compositions of Example 6 and Comparative Examples 8 and 9 are shown. DETAILED DESCRIPTION

[0062] Hereinafter, embodiments of the present application will be specifically described, but the present application is not limited thereto, and various modifications can be made within the scope of the gist thereof.

[0063] <Composition>

[0064] One embodiment of the present application relates to a composition comprising oxidized cellulose and / or nano cellulose, and a thickening agent, the oxidized cellulose being an oxidized product of a cellulose-based raw material obtained from hypochlorous acid or a salt thereof, and the nano cellulose being a defibrillated product of the oxidized cellulose.

[0065] The dispersion liquid comprising the oxidized cellulose and / or nano cellulose in the present embodiment has a tendency to have a low viscosity, as compared with a dispersion liquid comprising oxidized cellulose and / or nano cellulose obtained by other methods (e.g., TEMPO oxidation or mechanical defibration) (hereinafter also referred to as "comparative cellulose").

[0066] Surprisingly, the viscosity of the dispersion liquid comprising the comparative cellulose is difficult to increase even when mixed with a thickening agent, in contrast to the dispersion liquid comprising the oxidized cellulose and / or nano cellulose in the present embodiment, which significantly increases in viscosity when mixed with a thickening agent. Thus, the viscosity can be increased with a small amount of thickening agent, and therefore the adjustment of the viscosity can be easily performed.

[0067] In addition, the dispersion liquid comprising the oxidized cellulose and / or nano cellulose in the present embodiment preferably exhibits thixotropy, and thus the viscosity can be temporarily reduced by the application of force. Thereby, for example, in the case where the dispersion liquid comprising the oxidized cellulose and / or nano cellulose in the present embodiment is used as a paint, a cosmetic, or the like, the viscosity is reduced at the time of application and thus the use is facilitated, whereas the viscosity is increased after the application and thus the retention is facilitated.

[0068] As a reason for the significant increase in viscosity due to the mixing of the oxidized cellulose and / or nano cellulose with the thickening agent in the present embodiment, it is presumed that an interaction (preferably a hydrophobic interaction) occurs between the oxidized cellulose and / or the nano cellulose and the thickening agent, but the present application is not limited to the above presumption.

[0069] The pH of the composition of the present embodiment is not particularly limited, and is preferably in the range of 0 or more and 14.0 or less from the viewpoint of inhibiting the decrease in viscosity.

[0070] The lower limit value of the pH of the composition of the present embodiment is preferably 2.0, and more preferably 2.5, from the viewpoint of maintaining the viscosity.

[0071] The upper limit value of the pH of the composition of the present embodiment is preferably 13.0, and more preferably 12.0, from the viewpoint of maintaining the viscosity.

[0072] The pH of the composition of the present embodiment is preferably 2.0 or more and 13.0 or less, and more preferably 2.5 or more and 12.0 or less.

[0073] The pH of the composition of the present embodiment can be in the range of 0 or more and less than 7.0, in the range of 0 or more and 6.9 or less, in the range of 0 or more and 6.8 or less, in the range of 0 or more and 6.7 or less, in the range of 0 or more and 6.6 or less, in the range of 0 or more and 6.5 or less, in the range of more than 7.0 and 14.0 or less, in the range of 7.1 or more and 14.0 or less, in the range of 7.2 or more and 14.0 or less, in the range of 7.3 or more and 14.0 or less, in the range of 7.4 or more and 14.0 or less, or in the range of 7.5 or more and 14.0 or less.

[0074] The range of the pH of the composition of the present embodiment can be a range obtained by appropriately combining the ranges. As a specific example of the combined range, for example, the range of 0 or more and less than 7.0, and the range of more than 7.0 and 14.0 or less, or the range of 0 or more and less than 7.0, and the range of 7.5 or more and 14.0 or less can be given.

[0075] The pH of the composition can be adjusted, for example, by adding a pH adjuster described later.

[0076] The pH of the composition of the present embodiment can be measured using a pH meter.

[0077] The amount of the oxidized cellulose and / or the nanocellulose in the present embodiment is not particularly limited, and is preferably 0.01 to 50% by mass, more preferably 0.1 to 30% by mass, further preferably 0.1 to 20% by mass, and particularly preferably 0.1 to 15% by mass, relative to the mass of the composition. In the case where both the oxidized cellulose and the nanocellulose are contained in the composition, the amount refers to the total amount of the oxidized cellulose and the nanocellulose.

[0078] The composition according to the present embodiment can also not contain a dispersion medium. In other words, the composition of the present embodiment can be in a dry state. The composition in a dry state can be mixed with a dispersion medium as needed, and can be adjusted to an appropriate viscosity.

[0079] The composition of the present embodiment preferably contains a dispersion medium. The dispersion medium preferably contains water, and more preferably contains only water from the viewpoint of safety. In the present specification, the composition containing water as a dispersion medium is referred to as a "water-based composition".

[0080] The viscosity of the water-based composition of the present embodiment can be appropriately adjusted according to the intended use. The viscosity of the water-based composition can be, for example, 0.01 to 1000 Pa·s, 0.1 to 100 Pa·s, or 0.1 to 10 Pa·s.

[0081] In the present specification, unless otherwise specified, the "viscosity" refers to a value obtained by using a rheometer of a shear type at 25°C, 0.01 to 100 s -10.1 s -1 viscosity at the time of the shearing speed of 10 s

[0082] Regarding the viscosity of the aqueous composition of the present embodiment, it is preferable that the viscosity be higher than the viscosity of a control composition obtained by removing the thickening agent from the aqueous composition by 10 to 1 x 10 -1 6 %, more preferably 100 to 1 x 10 5 %, further preferably 1 x 10 3 ~1 x 10 5 % in the measurement of the viscosity at the shearing speed of 10 s

[0083] The viscosity increase rate (%) = [(viscosity of the aqueous composition - viscosity of the control composition) / (viscosity of the control composition)] x 100

[0084] [Oxidized cellulose]

[0085] The oxidized cellulose in the present embodiment is an oxide of a cellulose-based raw material obtained from hypochlorous acid or a salt thereof, and refers to a substance before fibrillation.

[0086] As the hypochlorous acid or a salt thereof, for example, hypochlorous acid water, sodium hypochlorite, potassium hypochlorite, calcium hypochlorite, and ammonium hypochlorite can be exemplified.

[0087] The amount of use of the hypochlorous acid or a salt thereof is not particularly limited, and it is preferable to use it in such a manner that the effective chlorine concentration of the reaction system becomes 6 to 43 mass%. The effective chlorine concentration can be a low concentration of 6 to 14 mass%, or a high concentration of 14 to 43 mass%.

[0088] The definition of the effective chlorine concentration of the hypochlorous acid or a salt thereof is described in International Publication No. 2022 / 009979.

[0089] The cellulose-based raw material is not particularly limited as long as it is a material in which cellulose is the main component, and for example, pulp, natural cellulose, and fine cellulose obtained by mechanically treating cellulose to depolymerize it can be exemplified. The cellulose-based raw material preferably has a crystal structure of type I. As the cellulose-based raw material, commercially available products such as crystalline cellulose using pulp as a raw material can be used directly. In addition, unused biomass containing a large amount of cellulose components such as soybean dregs and soybean hulls can be used as a raw material. In addition, in order to make the oxidizing agent used easily penetrate into the raw material pulp, the cellulose-based raw material can be pretreated with an alkali of an appropriate concentration.

[0090] Note that the main component of plants is cellulose, and a substance in which cellulose molecules are bundled is called cellulose microfibril. Cellulose in the cellulose-based raw material is also contained in the form of cellulose microfibril.​

[0091] (N-oxyl compound)

[0092] The oxidized cellulose in the present embodiment substantially does not contain an N-oxyl compound. By substantially not containing an N-oxyl compound, the influence on the environment and the human body is sufficiently reduced, and the safety is high. As the N-oxyl compound, for example, 2,2,6,6-tetramethylpiperidine-1-oxide (TEMPO) can be exemplified.

[0093] In the present specification, "substantially not containing an N-oxyl compound" means that an N-oxyl compound is not used in the production of the oxidized cellulose, the oxidized cellulose does not contain an N-oxyl compound at all, or the content of the N-oxyl compound is 2.0 mass ppm or less, preferably 1.0 mass ppm or less, with respect to the total amount of the oxidized cellulose.

[0094] Further, even in the case where the content of the N-oxyl compound is preferably 2.0 mass ppm or less, more preferably 1.0 mass ppm or less, in terms of the increase amount from the cellulose-based raw material, it means "substantially not containing an N-oxyl compound".

[0095] The content of the N-oxyl compound can be measured by a publicly known means. As the publicly known means, a method using a micro total nitrogen analyzer (for example, TN-2100H manufactured by Nittoseiko Analytech Co., Ltd.) can be exemplified.

[0096] [Carboxyl group amount]

[0097] The carboxyl group amount of the oxidized cellulose in the present embodiment is preferably 0.1 to 3.0 mmol / g, more preferably 0.2 to 2.0 mmol / g, further preferably 0.3 to 1.5 mmol / g, particularly preferably 0.4 to 1.2 mmol / g, and most preferably 0.5 to 0.9 mmol / g.

[0098] The carboxyl group amount of the oxidized cellulose can be measured by the method described in International Publication No. 2022 / 009979.

[0099] For the oxidized cellulose of the present embodiment, it is appropriate to have a structure in which at least 2 of the hydroxyl groups of the glucopyranose ring constituting cellulose are oxidized, and more specifically, it is preferable to have a structure in which the hydroxyl groups at the 2nd and 3rd positions of the glucopyranose ring are oxidized to introduce dicarboxyl groups. Further, it is preferable that the hydroxyl group at the 6th position of the glucopyranose ring is not oxidized and remains as a hydroxyl group. Note that the position of the carboxyl group in the glucopyranose ring can be analyzed by solid 13 C-NMR spectroscopy.

[0100] Artificial silk has the same chemical structure as cellulose, and its oxide (oxidized artificial silk) is water-soluble. By dissolving the oxidized artificial silk in heavy water, a one-dimensional solution 13 C-NMR measurement, a peak attributed to carbon of carboxyl group is observed at 165 to 185 ppm. In one mode of the oxide of the cellulose-based raw material obtained from hypochlorous acid or a salt thereof, two signals appear in this chemical shift range. Further, by solution two-dimensional NMR measurement, it can be determined that carboxyl groups are introduced to positions 2 and 3.

[0101] In the solid state of the oxide of the cellulose-based raw material obtained from hypochlorous acid or a salt thereof 13 In C-NMR, in the case where the amount of introduction of carboxyl group is large, two signals appear at 165 to 185 ppm, and in the case where the amount of introduction of carboxyl group is small, a very wide signal can appear. From the results of the oxidized artificial silk, the signals of carboxyl carbon introduced to positions 2 and 3 are close, and in the solid state 13 In C-NMR, the separation of two signals is not sufficient. Therefore, in the case where the amount of introduction of carboxyl group is small, a wide signal is observed. That is, in the solid state 13 In the C-NMR spectrum, by evaluating the width of the peak appearing at 165 to 185 ppm, it can be confirmed that carboxyl groups are introduced to positions 2 and 3.

[0102] That is, in the solid state 13 In the C-NMR spectrum, the peak in the range of 165 ppm to 185 ppm is baselined, the total area value is calculated, and then the ratio of the two peak area values obtained by vertically dividing the area value at the peak top (large area value / small area value) is calculated, and if the ratio of the peak area values is 1.2 or more, it can be said that it is a wide peak.

[0103] In addition, the presence or absence of the above-mentioned wide peak can be determined by the ratio of the length L' of the perpendicular line from the above-mentioned peak top to the baseline to the length L of the baseline in the range of 165 ppm to 185 ppm. That is, if the ratio L' / L is 0.1 or more, it can be determined that a wide peak is present. The above-mentioned ratio L' / L can be 0.2 or more, can be 0.3 or more, can be 0.4 or more, and can be 0.5 or more. The upper limit value of the ratio L' / L is not particularly limited, and is usually 3.0 or less, can be 2.0 or less, and can be 1.0 or less.

[0104] The structure of the above-mentioned pyranoglucose ring can also be determined by analysis according to the method described in Sustainable Chem. Eng. 2020, 848, 17800-17806.

[0105] (Viscosity average degree of polymerization)

[0106] The viscosity-average degree of polymerization of the oxidized cellulose in the present embodiment is preferably from 30 to 500, more preferably from 60 to 300, further preferably from 70 to 150, and particularly preferably from 80 to 130.

[0107] The viscosity-average degree of polymerization is an average degree of polymerization determined by a viscosity method. The viscosity-average degree of polymerization can be determined by the method described in International Publication No. 2022 / 009979.

[0108] [Method for producing oxidized cellulose]

[0109] The oxidized cellulose in the present embodiment can be produced by oxidizing a cellulose-based raw material with hypochlorous acid or a salt thereof. As a specific production method, for example, the methods described in International Publication No. 2022 / 009979, International Publication No. 2022 / 009980 can be cited. The oxidized cellulose can also be obtained as a commercially available product, and for example, ARON FINBRO (registered trademark) manufactured by Toa Gosei Co., Ltd., and the like can be cited.

[0110] [Nanocellulose]

[0111] The nanocellulose in the present embodiment is an oxide of a cellulose-based raw material obtained from hypochlorous acid or a salt thereof, and refers to a substance after fibrillation.

[0112] Nanocellulose indicates a general term for a substance after the fibrillation of cellulose, and includes fine cellulose fibers, cellulose nanocrystals (CNC), and the like. The fine cellulose fibers are also referred to as cellulose nanofibers (CNF). From the viewpoint of increasing the viscosity, the nanocellulose is preferably CNF. The nanocellulose preferably has an amorphous portion. The CNF has an amorphous portion, and the CNC does not have an amorphous portion.

[0113] The nanocellulose in the present embodiment contains a carboxyl group. The carboxyl group can be of the H type (-COOH), or of the salt type. The type of the salt is not particularly limited, and for example, alkali metal salts such as lithium salts, sodium salts, potassium salts, and the like; alkaline earth metal salts such as calcium salts, barium salts, and the like; other metal salts such as magnesium salts, aluminum salts, and the like; ammonium salts, organic amine salts, and the like can be cited.

[0114] The nanocellulose is a collection of 1 unit of fiber. In the case where the nanocellulose contains carboxylated nanocellulose, it is only necessary to contain at least 1 carboxylated nanocellulose, and the carboxylated nanocellulose is preferably the main component. Here, the carboxylated nanocellulose being the main component means that the proportion of the carboxylated nanocellulose in the total amount of the nanocellulose is more than 50% by mass, preferably more than 70% by mass, and more preferably more than 80% by mass. The upper limit of the above proportion is 100% by mass, and can be 98% by mass, or 95% by mass.

[0115] (N-oxyl compound)

[0116] The nanocellulose in the present embodiment does not substantially contain an N-oxyl compound. The meaning of the nanocellulose "not substantially containing an N-oxyl compound" and the method for measuring the content of the N-oxyl compound are as described in the above [Oxidized cellulose] column of (N-oxyl compound).

[0117] (carboxyl group amount)

[0118] The carboxyl group amount of the nanocellulose in the present embodiment and the method for measuring the same are as described in the above [Oxidized cellulose] column of (carboxyl group amount).

[0119] (average fiber length)

[0120] The average fiber length of the nanocellulose in the present embodiment is preferably 50 to 700 nm, more preferably 50 to 500 nm, further preferably 50 to 300 nm, more further preferably 60 to 300 nm, and particularly preferably 70 to 200 nm.

[0121] [average fiber width]

[0122] The average fiber width of the nanocellulose in the present embodiment is preferably 1 to 200 nm, more preferably 1 to 15 nm, further preferably 1 to 10 nm, and particularly preferably 1 to 5 nm.

[0123] The average fiber width and the average fiber length of the nanocellulose can be measured by the method described in International Publication No. 2022 / 009980.

[0124] (aspect ratio)

[0125] The aspect ratio (average fiber length / average fiber width) of the nanocellulose in the present embodiment is preferably 20 to 200, more preferably 30 to 190, and further preferably 40 to 180.

[0126] (Zeta potential)

[0127] The Zeta potential of the nanocellulose in the present embodiment is preferably -30 mV or less, more preferably -90 mV or more and -30 mV or less, further preferably -80 mV or more and -30 mV or less, more further preferably -70 mV or more and -30 mV or less, and particularly preferably -65 mV or more and -35 mV or less.

[0128] The Zeta potential can be measured by the method described in International Publication No. 2022 / 009980.

[0129] (transmittance)

[0130] The nanocellulose dispersion in which the nanocellulose is dispersed in the dispersion medium in the present embodiment has less light scattering of the cellulose fibers and can exhibit a high light transmittance. Specifically, the light transmittance in a mixed solution in which the nanocellulose is mixed with water to have a solid content concentration of 0.1% by mass is preferably 95% or greater, more preferably 96% or greater, further preferably 97% or greater, and particularly preferably 99% or greater. The light transmittance is a value at a wavelength of 660 nm measured using a spectrophotometer.

[0131] The light transmittance can be measured by the method described in International Publication No. 2022 / 009979.

[0132] [Method for producing nanocellulose]

[0133] The nanocellulose in the present embodiment can be produced by defibrating the above-described oxidized cellulose. As a specific production method, for example, the methods described in International Publication No. 2022 / 009979, International Publication No. 2022 / 009980 can be cited. The nanocellulose can also be obtained by defibrating a commercially available product of oxidized cellulose (for example, ARON FIN BRO (registered trademark) manufactured by Toagosei Co., Ltd., or the like).

[0134] [Thickening agent]

[0135] The composition of the present embodiment contains a thickening agent. By combining the oxidized cellulose and / or the nanocellulose in the present embodiment with the thickening agent, the viscosity can be significantly increased. The thickening agent can be used alone as one kind, or two or more kinds can be used in combination.

[0136] The thickening agent is preferably a thickening polysaccharide. The thickening polysaccharide is preferably water-soluble. In the present specification, “water-soluble” means that the amount of dissolution in 100 g of water at 20°C is 1 g or greater. The above-described amount of dissolution is preferably 3 g or greater, more preferably 10 g or greater, and further preferably 20 g or greater.

[0137] As the thickening polysaccharide, for example, methylcellulose, carboxymethylcellulose, guar gum, xanthan gum, locust bean gum, cassia gum, gellan gum, psyllium gum, gum tragacanth, gum karaya, gum arabic, tamarind gum, tara gum, gum okra, carrageenan, pectin, pullulan, curdlan, starch, gelatin, agar, alginic acid, and soybean polysaccharide can be cited.

[0138] The thickening agent can be a thickening agent in the present embodiment having a hydrophobic region capable of hydrophobic interaction with the oxidized cellulose and / or the nanocellulose (hereinafter referred to as “hydrophobic thickening agent”).

[0139] As the hydrophobic region of the hydrophobic thickening agent, for example, a continuous ring structure, and a chain or branched hydrocarbon chain structure, and the like can be cited.

[0140] Hydrophobic thickeners having a continuous ring structure are obtained, for example, by polymerizing a monomer having a ring structure. As the ring structure, for example, an aromatic hydrocarbon structure and an alicyclic hydrocarbon structure can be exemplified. The ring structure is preferably a cycloalkane structure, and more preferably a cyclohexane structure. The thickening polysaccharide generally has a continuous cyclohexane structure, and thus is included in the hydrophobic thickener.

[0141] The amount of the thickener is appropriately adjusted according to the desired viscosity, and is preferably 0.1 to 40% by mass, more preferably 0.3 to 35% by mass, further preferably 0.5 to 30% by mass, and particularly preferably 0.5 to 20% by mass, relative to the mass (solid content) of the oxidized cellulose and / or the nanocellulose in the present embodiment. Note that, in the case where both the oxidized cellulose and the nanocellulose are contained in the composition, the "mass (solid content) of the oxidized cellulose and / or the nanocellulose" means the "total mass (solid content) of the oxidized cellulose and the nanocellulose". The dispersion liquid containing the oxidized cellulose and the nanocellulose in the present embodiment can significantly increase the viscosity with a small amount of the thickener.

[0142] [Salts]

[0143] The composition of the present embodiment can further contain a salt. In the present specification, a salt refers to a compound composed of a positive ion (hereinafter also referred to as "cation") and a negative ion (hereinafter also referred to as "anion"). The viscosity increased by the combination of the oxidized cellulose and / or the nanocellulose with the thickener in the present embodiment can be maintained without being decreased even if a salt is contained.

[0144] The mechanism of the increase in viscosity is as described above, and it is presumed that the interaction (preferably, hydrophobic interaction) between the oxidized cellulose and / or the nanocellulose and the thickener is difficult to be affected by a salt, and thus it is presumed that the decrease in viscosity can be suppressed even if a salt is present.

[0145] The salt can be used alone as one kind, or two or more kinds in combination.

[0146] The salt can be an inorganic salt, an organic salt, or a mixture thereof.

[0147] As the cation constituting the inorganic salt or the organic salt, for example, the ions of alkali metals such as lithium ion (Li + ), sodium ion (Na + ), and potassium ion (K + ); the ions of alkaline earth metals such as magnesium ion (Mg 2+ ), and calcium ion (Ca 2+ ); and iron ions (Fe 3+ , Fe 2+ ), copper ions (Cu 2+ , Cu + ) and the like; and zinc ions (Zn 2+ ), aluminum ions (Al 3+ ) and the like of metals belonging to Group 12 or Group 13. Of these cations, from the viewpoint of maintaining viscosity, a cation having a valence of 1 is preferably used.

[0148] As anions constituting inorganic salts or organic salts, for example, halogen ions such as chloride ions (CI - ), bromide ions (Br - ), iodide ions (I - ); sulfate ions (SO4 2- ); nitrate ions (NO3 - ); carbonate ions (CO3 2- ); bicarbonate ions (HCO3 - ); bisulfate ions (HSO4 - ); phosphate ions (PO4 3- ); hydrogen phosphate ions (HPO4 2- ); dihydrogen phosphate ions (H2PO4 - ); sulfite ions (SO3 2- ); thiosulfate ions (S2O3 2- ); chlorate ions (CI O3 - ); perchlorate ions (CI O4 - ); and ions having a group obtained by removing a hydrogen ion (H + ) from an acid group such as a carboxyl group (-C(=O)-OH), a sulfo group (-S(=O)2-OH) and the like.

[0149] As the inorganic salt, for example, the following can be listed: chlorides of alkali metals such as sodium chloride (NaCl) and potassium chloride (KCl); hydrochlorides such as ammonium chloride (NH4Cl); sulfates such as sodium sulfate (Na2SO4), potassium sulfate (K2SO4), ammonium sulfate ((NH4)2SO4), magnesium sulfate (MgSO4), aluminum sulfate (Al2(SO4)3), nickel sulfate (NiSO4), alum (AlK(SO4)2), and ammonium alum (Al(NH4)(SO4)2); nitrate salts such as sodium nitrate (NaNO3), potassium nitrate (KNO3), ammonium nitrate (NH4NO3), calcium nitrate tetrahydrate (Ca(NO3)2-4H2O), and calcium nitrate (Ca(NO3)); carbonates such as potassium carbonate (K2CO3); bicarbonates such as potassium bicarbonate (KHCO3) and sodium bicarbonate (NaHCO3); chlorides of alkaline earth metals such as calcium chloride (CaCl2) and magnesium chloride (MgCl2); hydrogen phosphates such as sodium dihydrogen phosphate (NaH2PO4), disodium hydrogen phosphate (Na2HPO4), potassium dihydrogen phosphate (KH2PO4), dipotassium hydrogen phosphate (K2HPO4), ammonium dihydrogen phosphate (NH4H2PO4), and diammonium hydrogen phosphate ((NH4)2HPO4); phosphates such as trisodium phosphate (Na3PO4); sulfites such as sodium sulfite (Na2SO3); chlorates such as potassium chlorate (KClO3); perchlorates such as sodium perchlorate (NaClO4); thiosulfates such as sodium thiosulfate (Na2S2O3); bromides of alkali metals such as potassium bromide (KBr) and sodium bromide (NaBr); iodides of alkali metals such as potassium iodide (KI) and sodium iodide (NaI); and borates such as borax (Na2B4O7).

[0150] These inorganic salts can be used singly or in combination of two or more.

[0151] Among these cations, from the viewpoint of maintaining the viscosity, an inorganic salt having a monovalent cation is preferably used.

[0152] As the organic salt, for example, acetate, lactate, maleate, fumarate, tartrate, methanesulfonate, p-toluenesulfonate, triethanolamine salt, and amino acid salt can be listed.

[0153] The amount of the salt is preferably 0.01 to 10% by mass, more preferably 0.01 to 5% by mass, and further preferably 0.05 to 5% by mass, with respect to the mass of the composition.

[0154] The amount of the salt is preferably 1 to 1000 mass%, more preferably 1 to 500 mass%, and further preferably 5 to 500 mass% with respect to the mass (solid content) of the oxidized cellulose and / or the nanocellulose in the present embodiment. Note that, in the case where both the oxidized cellulose and the nanocellulose are contained in the composition, the "mass (solid content) of the oxidized cellulose and / or the nanocellulose" refers to the "total mass (solid content) of the oxidized cellulose and the nanocellulose".

[0155] [pH adjusting agent]

[0156] The composition of the present embodiment can further contain a pH adjusting agent. In the present specification, the pH adjusting agent refers to an agent having an action of bringing the pH to a prescribed range. The viscosity that is increased by the combination of the oxidized cellulose and / or the nanocellulose with the thickening agent in the present embodiment can be maintained without being decreased even if the pH adjusting agent is contained.

[0157] The mechanism of the increase in viscosity is as described above, and it is presumed that the interaction (preferably, hydrophobic interaction) between the oxidized cellulose and / or the nanocellulose and the thickening agent is generated, the interaction is difficult to be affected by the pH, and thus it is presumed that the decrease in viscosity is inhibited even if the pH is changed.

[0158] The pH adjusting agent can be used alone as one kind, or two or more kinds can be used in combination.

[0159] The pH adjusting agent can be any one of an acid, a base, or a neutralizing agent, and preferably contains an acid or a base. In addition, as the pH adjusting agent, an acid and a neutralizing agent can be used in combination, or a base and a neutralizing agent can be used in combination.

[0160] The acid can be an organic acid, an inorganic acid, or a mixture thereof.

[0161] As the organic acid, citric acid, tartaric acid, fumaric acid, malic acid, maleic acid, gluconic acid, succinic acid, ascorbic acid, glycolic acid, and salicylic acid can be exemplified.

[0162] As the inorganic acid, hydrochloric acid, sulfuric acid, phosphoric acid, and sulfamic acid can be exemplified.

[0163] The base can be an organic base, an inorganic base, or a mixture thereof.

[0164] As the organic base, triethanolamine, urea peroxide, and cement phosphoric acid can be exemplified.

[0165] As the inorganic base, ammonia, ammonium hydroxide, and alkali metal salts of lithium, sodium, and potassium can be exemplified.

[0166] As the neutralizing agent, there is no particular limitation as long as it is a substance having an effect of adjusting to a target pH. The neutralizing agent can be used to adjust or maintain the level of acidity or alkalinity. The neutralizing agent can also be expressed as a buffering agent. As the neutralizing agent, citric acid, sodium carbonate, phosphoric acid, ammonium hydroxide, and glycolic acid, for example, can be listed.

[0167] The amount of the pH adjusting agent can be appropriately changed depending on the target pH. The pH of the composition of the present embodiment is as described above.

[0168] [Optional Component]

[0169] The composition of the present embodiment can contain a further component (optional component). Even if the optional component is contained, the thickening effect can be exerted.

[0170] The optional component can be appropriately selected depending on the target use, and resins, pigments, surfactants, antifoaming agents, preservatives, plasticizers, stabilizers, and antioxidants, for example, can be listed.

[0171] [Cosmetics]

[0172] As the composition of the present embodiment, paints and cosmetics, and preferably cosmetics, can be listed.

[0173] As the cosmetics, makeup cosmetics, hair cosmetics, skin cosmetics, perfumes, eau de Cologne, bath cosmetics, nail cosmetics, lip care cosmetics, and body powders, for example, can be listed.

[0174] As the makeup cosmetics, lipsticks, lip glosses, and the like, lip cosmetics; eye shadows, eye liners, blushes, and the like, point makeup cosmetics; and foundations, concealers, and the like, base makeup cosmetics, for example, can be listed.

[0175] As the hair cosmetics, hair dressings, hair colorants (hair dyes), shampoos, and hair rinses, for example, can be listed.

[0176] As the skin cosmetics, toners, lotions, creams, emulsions, sunburn-preventing cosmetics, sun-protecting cosmetics, postoperative care lotions, cleansers, and masks, for example, can be listed.

[0177] As the nail cosmetics, nail polishes, cuticle oils, and nail polish removers, for example, can be listed.

[0178] The cosmetics in the present specification also include quasi-drugs. That is, cosmetics containing effective components for the purpose of prevention, hygiene, and the like are also included in the cosmetics of the present specification.

[0179] In addition, for example, in the case of a hair colorant (hair dye), it is equivalent to both a cosmetic and a quasi-drug. As the hair colorant (hair dye), the following forms can be listed: hair dyes, permanent hair dyes such as hair bleaching agents, depigmenting agents such as hair bleaching agents, hair care agents, color care agents, semi-permanent hair dyes such as hair care agents, temporary hair dyes such as mascara, hair dye sprays, hair markers, hair foundation liquids, and the like. The hair colorant (hair dye) in the present specification includes these forms.

[0180] Another embodiment of the present application relates to a composition comprising cellulose and a thickening agent, the cellulose comprising oxidized cellulose and / or nanocellulose, the oxidized cellulose having a structure in which the hydroxyl groups at the 2nd and 3rd positions of a glucopyranose ring are oxidized to introduce dicarboxyl groups, and the nanocellulose being a defibrillated product of the oxidized cellulose. As to details of the composition of the present embodiment (preferred properties and ingredients, etc.), the description of the composition of the above-mentioned embodiment is appropriately quoted.

[0181] <Method for producing a composition>

[0182] One embodiment of the present application relates to a method for producing a composition, which includes a step of mixing cellulose, a thickening agent, and, as necessary, a salt and / or a pH adjuster, the cellulose comprising oxidized cellulose and / or nanocellulose and substantially not containing an N-oxyl compound, the oxidized cellulose being an oxide of a cellulose-based raw material obtained by oxidation of hypochlorous acid or a salt thereof, and the nanocellulose being a defibrillated product of the oxidized cellulose.

[0183] Details of the production method of the present embodiment (for example, details of the composition and its materials) are in accordance with the description of the above-mentioned <Composition> column.

[0184] The oxidized cellulose obtained by the oxidation reaction of hypochlorous acid or a salt thereof is easily defibrillated, and thus even if the mixing with the thickening agent is slow, at least a part of the oxidized cellulose is defibrillated into nanocellulose.

[0185] Another embodiment of the present application relates to a method for producing a composition, which includes a step of mixing cellulose and a thickening agent, the cellulose comprising oxidized cellulose and / or nanocellulose, the oxidized cellulose having a structure in which the hydroxyl groups at the 2nd and 3rd positions of a glucopyranose ring are oxidized to introduce dicarboxyl groups, and the nanocellulose being a defibrillated product of the oxidized cellulose. As to details of the production method of the present embodiment, the description of the production method of the above-mentioned embodiment is appropriately quoted.

[0186] <Method for adjusting the viscosity of a composition>

[0187] One embodiment of the present application relates to a method for adjusting the viscosity of an aqueous composition containing cellulose, which includes a step of mixing the aqueous composition, a thickening agent, and, as necessary, a salt and / or a pH adjuster, the cellulose containing oxidized cellulose and / or nanocellulose and substantially not containing an N-oxyl compound, the oxidized cellulose being an oxide of a cellulose-based raw material derived from hypochlorous acid or a salt thereof, the nanocellulose being a defibrillated product of the oxidized cellulose.

[0188] Details of the method according to the present embodiment (e.g., details of the aqueous composition and materials thereof) are described in the above section of <Composition>.

[0189] The viscosity of the aqueous composition is preferably increased by 10 to 1 x 10 -1 % at a shear rate of 10 s 6 % at a shear rate of 10 s 5 % at a shear rate of 10 s 3 % at a shear rate of 10 s 5 % at a shear rate of 10 s

[0190] Another embodiment of the present application relates to a method for adjusting the viscosity of an aqueous composition containing cellulose, which includes a step of mixing the aqueous composition and a thickening agent, the cellulose containing oxidized cellulose and / or nanocellulose, the oxidized cellulose having a structure in which the hydroxyl groups at the 2nd and 3rd positions of a pyranoglucose ring are oxidized to introduce dicarboxyl groups, the nanocellulose being a defibrillated product of the oxidized cellulose. Details of the adjusting method according to the present embodiment are appropriately cited from the description of the adjusting method according to the above embodiment.

[0191] Examples

[0192] Hereinafter, the present application will be described in more detail using examples and comparative examples, but the technical scope of the present application is not limited thereto.

[0193] Note that each value in the examples can be set to a preferable lower limit value or upper limit value in the embodiments of the present application. In addition, two values of the same kind in the examples can be appropriately combined to be a preferable numerical range.

[0194] [Manufacturing Example 1]

[0195] As the cellulose-based raw material, commercially available powdered cellulose was used.

[0196] In a beaker, 350 g of sodium hypochlorite 5-hydrate crystals having an effective chlorine concentration of 42 mass% was added, and pure water was added and stirred to obtain an aqueous sodium hypochlorite solution having an effective chlorine concentration of 21 mass%. To this, 35 mass% hydrochloric acid was added and stirred to prepare an aqueous solution having a pH of 11.0. After the aqueous sodium hypochlorite solution was heated to 30°C using a constant-temperature water bath while stirring at 200 rpm using a propeller-type stirring blade in a stirrer (Three-One Motor, BL600) manufactured by Shinko Rikagaku Co., Ltd., 50 g of the above-mentioned powdered cellulose was added.

[0197] After the supply of the cellulose-based raw material, in the same constant-temperature water bath, while adjusting the pH in the reaction to 11.0 by adding 48 mass% sodium hydroxide, the oxidation reaction was performed by stirring at 200 rpm using a propeller-type stirring blade in the above-mentioned stirrer for 30 minutes. After the completion of the reaction, the product was separated into solid and liquid by suction filtration using a PTFE membrane filter having a pore size of 0.1 μm to obtain oxidized cellulose. The obtained oxidized cellulose was washed with pure water, and the carboxyl group content of the filtered product (oxidized cellulose) after the washing was measured, and the result was 0.70 mmol / g.

[0198] In addition, the nitrogen content derived from the N-oxyl compound in the oxidized cellulose was measured as the nitrogen content using a micro total nitrogen analyzer (manufactured by Nittoseiko Analytech Co., Ltd., device name: TN-2100H), and the increase amount from the raw material pulp was calculated, and the result was 1 ppm or less.

[0199] Note that the effective chlorine concentration in the aqueous sodium hypochlorite solution was measured according to the following method.

[0200] (Measurement of effective chlorine concentration in aqueous sodium hypochlorite solution)

[0201] A 0.582 g aqueous solution of sodium hypochlorite 5-hydrate crystals was precisely measured in pure water, 50 ml of pure water was added, 2 g of potassium iodide and 10 ml of acetic acid were added, and immediately after the sealing, the mixture was left in the dark for 15 minutes. After 15 minutes, the free iodine was titrated with a 0.1 mol / L sodium thiosulfate solution, and the result (indicator: starch test solution) was 34.55 ml. A blank test was also performed for correction, and 1 ml of the 0.1 mol / L sodium thiosulfate solution was equivalent to 3.545 mg of Cl, and thus the effective chlorine concentration in the aqueous sodium hypochlorite solution was 21 mass%.

[0202] The carboxyl group content of the oxidized cellulose was measured according to the following method.

[0203] (Measurement of carboxyl group content)

[0204] In a 0.5 mass% oxidized cellulose water dispersion 60 ml, the concentration of the oxidized cellulose was adjusted, and then a 0.1 M aqueous hydrochloric acid solution was added to make it pH 2.5. After that, a 0.05 N aqueous sodium hydroxide solution was added dropwise, and the conductivity was measured until the pH became 11.0. The amount (a) of the sodium hydroxide consumed in the neutralization stage of the weak acid in which the conductivity was constant was used to calculate the carboxyl group amount (mmol / g) using the following equation.

[0205] Carboxyl group amount = a (ml) x 0.05 / mass of oxidized cellulose (g)

[0206] After the oxidized cellulose obtained in Production Example 1 was freeze-dried, the solid content of a sample that had been left at 23°C, 50% RH for 24 hours or more was measured. 13 C-NMR, and the results confirmed that the hydroxyl groups at the 2nd and 3rd positions of the pyranoglucose ring were oxidized to introduce carboxyl groups. The solid content of the sample is shown below. 13 Measurement conditions for C-NMR.

[0207] (1) Sample tube: Zirconium oxide tube (4 mm diameter)

[0208] (2) Magnetic field strength: 9.4 T (1H resonance frequency: 400 MHz)

[0209] (3) MAS rotation speed: 15 kHz

[0210] (4) Pulse sequence: CPMAS method

[0211] (5) Contact time: 3 ms

[0212] (6) Waiting time: 5 seconds

[0213] (7) Number of accumulations: 10,000 to 15,000

[0214] (8) Measuring device: JNM ECA-400 (manufactured by JEOL Ltd.)

[0215] In addition, the fact that the obtained oxidized cellulose has a structure in which the hydroxyl groups at the 2nd and 3rd positions of the pyranoglucose ring are oxidized to introduce carboxyl groups can also be confirmed from the results obtained by performing two-dimensional NMR measurement using a model molecule of the oxidized cellulose as a sample.

[0216] In addition, no solid content of the cellulose-based raw material related to the 6th position was observed. 13 C-NMR of the solid content of the oxidized cellulose 13 The spectral data of the C-NMR did not change, and thus it was judged that the hydroxyl group at the 6th position was not oxidized and remained as a hydroxyl group in the oxidized cellulose.

[0217] [Comparative Production Example 1]

[0218] The nanocellulose obtained by TEMPO oxidation was obtained by being produced according to Angew. Chem. Int. Ed. 2021, 60, 24630-24636. That is, it was produced by the following method.

[0219] To a beaker, 0.016 g of TEMPO and 0.1 g of sodium bromide were added, pure water was added and stirred to make an aqueous solution, and 1.0 g of powder pulp of Japan Paper Co., Ltd. (KC FLOCK W-100GK) was added as a cellulose-based raw material.

[0220] After the above aqueous solution was heated to 25°C in a constant temperature water bath with a stirrer, 0.1 mol / L sodium hydroxide was added and stirred to make an aqueous solution with a pH of 10.0. To this, 2.58 g of an aqueous sodium hypochlorite solution with an available chlorine concentration of 13.2 mass% was added, and in the same constant temperature water tank, the pH in the reaction was adjusted to 10.0 by adding 0.1 mol / L sodium hydroxide while maintaining the temperature at 25°C, and stirring was performed with a stirrer for 120 minutes.

[0221] After the reaction was completed, the product was separated by solid-liquid separation by suction filtration using a PTFE membrane filter with a pore size of 0.1 μm to obtain oxidized cellulose. The obtained filtrate was washed with pure water, and the carboxyl group content was measured. The carboxyl group content was 1.55 mmol / g, and the amount of the filtrate was about 1.0 g. In addition, the nitrogen content derived from N-oxyl compounds in the oxidized cellulose was measured as the nitrogen content using a micro total nitrogen analyzer (Nittoseiko Analytech Co., Ltd., device name: TN-2100H), and the increase amount from the raw pulp was calculated, and the result was 5 ppm. By mechanically fibrillating the oxidized cellulose, a nanocellulose aqueous dispersion (solid content 2.0 mass%) obtained by TEMPO oxidation was obtained.

[0222] [Comparative Production Example 2]

[0223] A commercially available powder cellulose was fibrillated in a starburst pattern to obtain a nanocellulose aqueous dispersion (solid content 2.0 mass%) obtained by mechanical fibrillation.

[0224] [Example 1]

[0225] The oxidized cellulose obtained in Production Example 1 was made into an aqueous dispersion (solid content about 10 mass%), and distilled water was added thereto to dilute it to a solid content of 5 mass%. In this state, a homomixer (TOKUSHU KIKA ROBO MICS) was used to stir at 10,000 rpm for 60 minutes to fibrillate the oxidized cellulose into CNF.

[0226] In addition, a 1 mass% aqueous solution of methylcellulose (MC) and distilled water were prepared. The solid content 5 mass% CNF aqueous dispersion, 1 mass% methylcellulose aqueous solution, distilled water were mixed to prepare a sample in a predetermined CNF / methylcellulose / water ratio (for the specific ratio, refer to the results).

[0227] The viscosity measurement of each sample was performed as described below.

[0228] The viscosity measurement was performed using a shear-type rheometer (Anton Paar, Physica MCR301), and a parallel disk-type jig with a diameter of 50 mm was used. The shear rate was set to 0.01 to 100 s -1 , and the temperature was set to 25°C. Two measurements were performed for one sample (one measurement was performed at a shear rate of 0.01 to 100 s -1 , and after the measurement was completed, the sample was left to stand for 20 seconds, and then a second measurement was performed at the same shear rate range), and the data of the second measurement was used.

[0229] [Comparative Example 1]

[0230] The solid content 2.0 mass% of the nanocellulose aqueous dispersion obtained by TEMPO oxidation manufactured in Comparative Production Example 1, 1 mass% of an aqueous methylcellulose solution, distilled water were mixed to prepare a sample in a predetermined CNF / methylcellulose / water ratio.

[0231] [Comparative Example 2]

[0232] The solid content 2.0 mass% of the nanocellulose aqueous dispersion obtained by mechanical defibrillation manufactured in Comparative Production Example 2, 1 mass% of an aqueous methylcellulose solution, distilled water were mixed to prepare a sample in a predetermined CNF / methylcellulose / water ratio.

[0233] The measurement results of the various samples in Example 1, Comparative Example 1, and Comparative Example 2 are shown in Figures 1-4 . Note that the % of each component in the graph indicates the mass% of each component with respect to the total amount of components of each sample.

[0234] [Example 2]

[0235] The oxidized cellulose obtained in Production Example 1 was made into an aqueous dispersion (solid content about 10 mass%), and distilled water was added thereto and diluted to a solid content of 5 mass%. In this state, a homogenizer (TOKUSHU KIKA ROBO MICS) was used to perform stirring at 10,000 rpm for 60 minutes, and the oxidized cellulose was defibrillated into CNF (defibrillation was performed in advance).

[0236] In addition, an aqueous solution of 1 mass% of methylcellulose was prepared. The CNF 5 mass% aqueous dispersion, the acrylic emulsion, the 1 mass% methylcellulose aqueous solution, and distilled water were mixed to prepare a sample 1 of a prescribed CNF / emulsion / methylcellulose ratio.

[0237] Viscosity measurement was performed by the same viscosity measurement method as in Example 1.

[0238] [Comparative Example 3]

[0239] A sample 2 in which CNF was removed from the sample of Example 2, a sample 3 in which methylcellulose was removed, and a sample 4 in which both CNF and methylcellulose were removed were prepared.

[0240] Viscosity measurement was performed by the same viscosity measurement method as in Example 1.

[0241] The composition of each sample in Example 2 and Comparative Example 3 is shown in Table 1, and the measurement results thereof are shown in Figure 5 .

[0242] [Table 1]

[0243]

[0244] [Example 3]

[0245] The oxidized cellulose obtained in Production Example 1 was made into an aqueous dispersion (solid content about 10 mass%) to which distilled water was added and diluted to a solid content of 5 mass%. The oxidized cellulose was fibrillated into CNF by stirring at 10,000 rpm for 60 minutes using a homogenizer (TOKUSHU KIKA ROBO MICS) in this state.

[0246] A sample in which CNF, methylcellulose, and water were mixed in a prescribed ratio was prepared.

[0247] Viscosity measurement was performed by the same viscosity measurement method as in Example 1.

[0248] [Example 4]

[0249] A sample in which guar gum (GG) was used instead of the methylcellulose of Example 3 was prepared.

[0250] Viscosity measurement was performed by the same viscosity measurement method as in Example 1.

[0251] The measurement results of each sample in Examples 3 and 4 are shown in Figure 6 . In addition, the % of each component in the graph indicates the mass% of each component with respect to the total amount of components of each sample.

[0252] [Example 5]

[0253] The oxidized cellulose obtained in Production Example 1 was made into an aqueous dispersion (solid content about 10 mass%), and distilled water was added thereto and diluted to a solid content of 7.5 mass%. In this state, a homomixer (TOKUSHU KIKA ROBOMICS) was used to stir for 60 minutes at 10,000 rpm, and the oxidized cellulose was fibrillated into CNF.

[0254] In addition, an aqueous solution of methylcellulose (MC) having a concentration of 1 mass% was prepared. In addition, an aqueous solution of sodium chloride (NaCl) having a concentration of 12.5 mass% and distilled water were prepared. The CNF aqueous dispersion having a solid content of 7.5 mass%, the aqueous methylcellulose solution having a concentration of 1 mass%, the aqueous sodium chloride solution having a concentration of 12.5 mass%, and the distilled water were mixed to prepare samples in which the ratio of CNF / methylcellulose / sodium chloride with respect to the amount of the entire composition was 1.0 mass% / 0.1 mass% / 0~1.0 mass%.

[0255] For each sample, viscosity measurement was performed by the same viscosity measurement method as in Example 1.

[0256] [Comparative Example 4]

[0257] An aqueous solution of Carbopol (registered trademark) 980 having a concentration of 12.5 mass% and distilled water were mixed to prepare samples in which the ratio of Carbopol (registered trademark) / sodium chloride with respect to the amount of the entire composition was 0.075 mass% / 0~1.0 mass%.

[0258] For each sample, viscosity measurement was performed by the same viscosity measurement method as in Example 1.

[0259] [Comparative Example 5]

[0260] An aqueous solution of Carbopol (registered trademark) 980 having a concentration of 12.5 mass% and distilled water were mixed to prepare samples in which the ratio of Carbopol (registered trademark) / sodium chloride with respect to the amount of the entire composition was 1.0 mass% / 0~1.0 mass%.

[0261] For each sample, viscosity measurement was performed by the same viscosity measurement method as in Example 1.

[0262] The results of viscosity measurement of Example 5 (CNF and MC) and Comparative Example 4 (Carbopol (registered trademark) 980) are shown in Table 1. Figure 7 The sample in which no salt was contained in Example 5 had the same degree of viscosity as the sample in which no salt was contained in Comparative Example 4. In Comparative Example 4, the viscosity was significantly reduced when the salt was added, but in Example 5, the reduction in viscosity was suppressed even when the salt was added.

[0263] Results of the viscosity measurement of Example 5 (CNF and MC) and Comparative Example 5 (Carbopol (registered trademark) 980) are shown in Table 1. Figure 8 The amount of CNF of Example 5 was the same as the amount of Carbopol (registered trademark) of Comparative Example 5. In Comparative Example 5, the viscosity decreased when salt was added, but in Example 5, the decrease in viscosity was suppressed even if salt was added.

[0264] [Comparative Example 6]

[0265] Using Carbopol (registered trademark) Ultrez 30 (hereinafter also referred to as Ultrez 30), a 12.5 mass% sodium chloride aqueous solution, distilled water were mixed to prepare a sample in which the ratio of Ultrez 30 / sodium chloride with respect to the amount of the entire composition was 0.075 mass% / 0~1.0 mass%.

[0266] For each sample, the viscosity measurement was performed by the same viscosity measurement method as Example 1.

[0267] [Comparative Example 7]

[0268] Using Ultrez 30, a 12.5 mass% sodium chloride aqueous solution, distilled water were mixed to prepare a sample in which the ratio of Ultrez 30 / sodium chloride with respect to the amount of the entire composition was 1.0 mass% / 0~1.0 mass%.

[0269] For each sample, the viscosity measurement was performed by the same viscosity measurement method as Example 1.

[0270] Results of the viscosity measurement of Example 5 (CNF and MC) and Comparative Example 6 (Ultrez 30) are shown in Table 2. Figure 9 The sample not containing salt in Example 5 and the sample not containing salt in Comparative Example 6 were the same degree of viscosity. In Comparative Example 6, the viscosity decreased significantly when salt was added, but in Example 5, the decrease in viscosity was suppressed even if salt was added.

[0271] Results of the viscosity measurement of Example 5 (CNF and MC) and Comparative Example 7 (Ultrez 30) are shown in Table 3. Figure 10 The amount of CNF of Example 5 was the same as the amount of Ultrez 30 of Comparative Example 7. In Comparative Example 7, the viscosity decreased when salt was added, but in Example 5, the decrease in viscosity was suppressed even if salt was added.

[0272] [Example 6]

[0273] The oxidized cellulose obtained in Manufacturing Example 1 was prepared into an aqueous dispersion (solid content approximately 10% by mass), and distilled water was added to dilute it to a solid content of 7.5% by mass. Under these conditions, the oxidized cellulose was decelluloseed into CNF by stirring at 10,000 rpm for 60 minutes using a homogenizer (TOKUSHU KIKA ROBOMICS).

[0274] In addition, prepare an aqueous solution of methylcellulose (MC) at a concentration of 1% by mass and distilled water. Mix 7.5% by mass CNF aqueous dispersion, 1% by mass methylcellulose aqueous solution, and distilled water to prepare a sample with a ratio of 1% by mass CNF / 0.1% by mass methylcellulose relative to the total composition.

[0275] Adjust the pH of the above sample using 0.5M hydrochloric acid or 0.5M sodium hydroxide aqueous solution. Use 0.5M hydrochloric acid to adjust towards the acidic side and 0.5M sodium hydroxide aqueous solution to adjust towards the alkaline side. Immerse the electrode of the pH meter (HORIBA D-51pH METER) into the screw tube containing the sample, and add the above reagent dropwise while confirming the value.

[0276] Viscosity measurements were performed using the same viscosity measurement method as in Example 1, with shear rates set to 1 [1 / s] and 10 [1 / s]. The results are shown below. Figure 11 .

[0277] [Comparative Example 8]

[0278] Carbopol (registered trademark) 980 was mixed with distilled water to prepare a sample in which Carbopol (registered trademark) accounted for 0.1% by mass of the total composition. Viscosity was measured in the same manner as in Example 6, except that this sample was used. The results are shown below. Figure 11 .

[0279] [Comparative Example 9]

[0280] Carbopol (registered trademark) Ultraz30 was mixed with distilled water to prepare a sample in which Ultraz30 accounted for 0.1% by mass of the total composition. Viscosity measurements were performed in the same manner as in Example 6, except that this sample was used. The results are shown below. Figure 11 .

[0281] like Figure 11 As shown, in the compositions of Example 6 (CNF and MC), there is a tendency to suppress viscosity reduction even when the pH changes from 7. On the other hand, in the compositions of Comparative Example 8 (Carbopol 980) or Comparative Example 9 (Ultrez 30), there is a tendency for viscosity to decrease when the pH changes from 7.

[0282] Thus, the dispersion liquid containing the oxidized cellulose including the oxide of the cellulose-based raw material obtained from hypochlorous acid or a salt thereof and / or the nanocellulose as a defibrillated product of the oxidized cellulose, and the thickening agent can increase the viscosity and can suppress the decrease in the viscosity caused by the change in the pH.

Claims

1. A composition comprising cellulose and a thickening agent, the cellulose comprising oxidized cellulose and / or nano cellulose and substantially not containing an N-oxyl compound, the oxidized cellulose being an oxidized product of a cellulose-based raw material by hypochlorous acid or a salt thereof, the nano cellulose being a defibrillated product of the oxidized cellulose.

2. A composition comprising cellulose and a thickening agent, the cellulose comprising oxidized cellulose and / or nano cellulose, the oxidized cellulose having a structure in which di-carboxyl groups are introduced by oxidation of hydroxyl groups at the 2nd and 3rd positions of a pyranoglucose ring, the nano cellulose being a defibrillated product of the oxidized cellulose.

3. The composition according to claim 1 or 2, wherein, the thickening agent being a thickening polysaccharide.

4. The composition according to claim 1 or 2, wherein, the thickening agent having a hydrophobic region capable of hydrophobic interaction with the oxidized cellulose and / or the nano cellulose.

5. The composition of claim 1 or 2, wherein, the amount of the thickening agent is 0.1 to 40 mass% in solid content with respect to the mass of the oxidized cellulose and / or the nano cellulose.

6. The composition according to claim 1 or 2, further comprising a salt.

7. The composition of claim 6, wherein, the amount of the salt is 0.01 to 10 mass% with respect to the composition.

8. The composition according to claim 1 or 2, further comprising a pH adjustor.

9. The composition of claim 8, wherein, the pH of the composition is in a range of 0 or more and 14.0 or less.

10. The composition of claim 8, wherein, the pH adjustor comprises an acid or a base.

11. The composition of claim 1 or 2, wherein, the cellulose comprises the nano cellulose.

12. The composition of claim 1 or 2, wherein, the composition is an aqueous composition.

13. The composition of claim 12, wherein, the viscosity of the aqueous composition is 0.01 to 1000 Pa-s.

14. The composition of claim 12, wherein, The viscosity of the aqueous composition is 10 to 1 x 10 6 higher than the viscosity of a control composition obtained by removing the thickening agent from the aqueous composition.

15. A composition comprising cellulose and a thickening agent, the cellulose comprising oxidized cellulose and / or nano cellulose and substantially not containing an N-oxyl compound, the oxidized cellulose being an oxidized product of a cellulose-based raw material by hypochlorous acid or a salt thereof, the nano cellulose being a defibrillated product of the oxidized cellulose, the pH of the composition is in a range of 0 or more and 14.0 or less.

16. A composition comprising cellulose and a thickening agent, the cellulose comprising oxidized cellulose and / or nano cellulose, the oxidized cellulose having a structure in which di-carboxyl groups are introduced by oxidation of hydroxyl groups at the 2nd and 3rd positions of a pyranoglucose ring, the nano cellulose being a defibrillated product of the oxidized cellulose, the pH of the composition is in a range of 0 or more and 14.0 or less.

17. The composition of any one of claims 1, 2, 15, and 16, wherein, the composition is a cosmetic.

18. A production method of a composition, comprising a step of mixing cellulose and a thickening agent, the cellulose comprising oxidized cellulose and / or nano cellulose and substantially not containing an N-oxyl compound, the oxidized cellulose being an oxidized product of a cellulose-based raw material by hypochlorous acid or a salt thereof, the nano cellulose being a defibrillated product of the oxidized cellulose.

19. A production method of a composition, comprising a step of mixing cellulose and a thickening agent, the cellulose comprising oxidized cellulose and / or nano cellulose, the oxidized cellulose having a structure in which di-carboxyl groups are introduced by oxidation of hydroxyl groups at the 2nd and 3rd positions of a pyranoglucose ring, the nano cellulose being a defibrillated product of the oxidized cellulose.

20. A method of adjusting the viscosity of an aqueous composition containing cellulose, comprising the step of mixing the aqueous composition with a thickening agent, the cellulose containing oxidized cellulose which is an oxide of a cellulose-based raw material obtained by hypochlorous acid or a salt thereof, and / or nanocellulose which is a defibrillated product of the oxidized cellulose, and substantially not containing an N-oxyl compound.

21. A method of adjusting the viscosity of an aqueous composition containing cellulose, comprising the step of mixing the aqueous composition with a thickening agent, the cellulose containing oxidized cellulose which has a structure in which hydroxyl groups at positions 2 and 3 of a glucopyranose ring are oxidized to introduce dicarboxyl groups, and / or nanocellulose which is a defibrillated product of the oxidized cellulose.

22. The method of claim 20 or 21, wherein, The viscosity of the aqueous composition is increased by 10 to 1 x 10 6 .

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