WO2023171748A1 - Cellulose material - Google Patents

Abstract

The purpose of the present invention is to provide: a cellulose material that has excellent recycling efficiency even when used as an additive for a resin component; and a cellulose material that has excellent recycling efficiency and tableting suitability. The present invention provides a cellulose material of a powder cellulose or the like containing an iron component in an amount of 1-50 ppm as detected by a triple-quadrupole inductively coupled plasma mass spectrometer. The cellulose material can be used as material for a molded body such as a tablet, an excipient, a rubber composition, a resin composition, and an industrial additive.

Description

cellulose material

The present invention relates to cellulose materials.

Cellulose materials such as powdered cellulose are used as reinforcing agents for resin materials such as rubber and plastics (for example, Patent Document 1).

JP2022-012875A

By the way, the importance of chemical recycling of plastics is attracting attention for environmental protection. When recycling a resin material containing a cellulose material as in the prior art described above by a method called a closed loop, the resin component and the cellulose component are usually separated during the process. However, cellulose materials have a low thermogravimetric residual rate and are difficult to separate from resin materials. There is also a need for powdered cellulose that can further increase tablet hardness.

The present invention has been made in view of the above, and provides a cellulose material that has good recyclability even when used as an additive for a resin component, and a cellulose material that has excellent recyclability and tabletability. The purpose is to

The present invention provides [1] to [17].
[1] A cellulose material in which the amount of iron component detected by a triple quadrupole-inductively coupled plasma mass spectrometer is 1 to 50 ppm.
[2] The cellulose material according to [1], wherein the amount of iron component detected by a triple quadrupole-inductively coupled plasma mass spectrometer is more than 10 ppm and less than 50 ppm.
[3] The cellulose material according to [1] or [2], wherein the ash content after heating at 800° C. for 2 hours is 0.13% by weight or more based on 100% by weight of the cellulose material before heating.
[4] The cellulose material according to any one of [1] to [3], which has a thermogravimetric residual rate at 500° C. of 10% or more.
[5] The cellulose material according to any one of [1] to [4], which has an average fiber width of 10 to 24 μm.
[6] The cellulose material according to [1], wherein the amount of iron component detected by a triple quadrupole-inductively coupled plasma mass spectrometer is 1 to 10 ppm.
[7] The cellulose material according to [6], wherein the ash content after heating at 800° C. for 2 hours is 1.0% by weight or less based on 100% by weight of the cellulose material before heating.
[8] The cellulose material according to any one of [1] to [7], which has a thermogravimetric residual rate at 400°C of 10 to 20%.
[9] The cellulose material according to any one of [1] to [8], which has an average fiber length/average fiber width of 3.0 to 8.0.
[10] The cellulose material according to any one of [1] to [9], which is powdered cellulose.
[11] The cellulose material according to [10], which has an average particle diameter of 5.0 to 150.0 μm.
[12] An industrial additive containing the cellulose material according to any one of [1] to [11].
[13] A resin composition comprising the cellulose material according to any one of [1] to [11].
[14] A rubber composition comprising the cellulose material according to any one of [1] to [11].
[15] An excipient containing the cellulose material according to any one of [1] to [11].
[16] A molded article comprising the cellulose material according to any one of [1] to [11].
[17] The molded article according to [16], which has a hardness of 30 to 100 MPa.

The present invention also provides the following [1-1] to [1-10].
[1-1] A cellulose material in which the amount of iron component detected by a triple quadrupole-inductively coupled plasma mass spectrometer is more than 10 ppm and less than 50 ppm.
[1-2] The cellulose material according to [1-1], wherein the ash content after heating at 800° C. for 2 hours is 0.13% by weight or more based on 100% by weight of the cellulose material before heating.
[1-3] The cellulose material according to [1-1] or [1-2], which has a thermogravimetric residual rate at 500° C. of 10% or more.
[1-4] The cellulose material according to any one of [1-1] to [1-3], having an average fiber width of 10 to 24 μm.
[1-5] The cellulose material according to any one of [1-1] to [1-4], which is powdered cellulose.
[1-6] The cellulose material according to [1-5], wherein the powdered cellulose has an average particle diameter of 5.0 to 150.0 μm.
[1-7] An industrial additive containing the cellulose material according to any one of [1-1] to [1-6].
[1-8] A resin composition containing the cellulose material according to any one of [1-1] to [1-6].
[1-9] A rubber composition comprising the cellulose material according to any one of [1-1] to [1-6].
[1-10] A molded article comprising the cellulose material according to any one of [1-1] to [1-6].

The present invention further provides the following [2-1] to [2-10].
[2-1] Powdered cellulose having an average particle diameter of 5.0 to 150.0 μm and an amount of iron component detected by a triple quadrupole-inductively coupled plasma mass spectrometer of 1 to 10 ppm.
[2-2] The powdered cellulose according to [2-1], wherein the ash content after heating at 800° C. for 2 hours is 1.0% by weight or less based on 100% by weight of the powdered cellulose before heating.
[2-3] The powdered cellulose according to [2-1] or [2-2], which has a thermogravimetric residual rate at 400°C of 10 to 20%.
[2-4] The powdered cellulose according to any one of [2-1] to [2-3], which has an average fiber length/average fiber width of 3.0 to 8.0.
[2-5] An excipient containing the powdered cellulose according to any one of [2-1] to [2-4].
[2-6] A molded article containing the powdered cellulose according to any one of [2-1] to [2-4].
[2-7] The molded article according to [2-6], which has a hardness of 30 to 100 MPa.
[2-8] An industrial additive containing the powdered cellulose according to any one of [2-1] to [2-4].
[2-9] A resin composition containing the powdered cellulose according to any one of [2-1] to [2-4].
[2-10] A rubber composition containing the powdered cellulose according to any one of [2-1] to [2-4].

According to the present invention, it is possible to provide a cellulose material that can exhibit a high thermogravimetric residual rate and has good recyclability as a biomass material when mixed with a resin. Further, according to the present invention, it is possible to provide powdered cellulose that can exhibit a high thermogravimetric residual rate, has excellent recyclability as a biomass material when mixed with resin, and has excellent tabletability. .

[1. Cellulose material]
A cellulose material is a material whose main component is cellulose and contains an iron component.

[1.1. Iron component]
Cellulosic materials contain iron components. The iron component may be bound to the cellulose molecules of the cellulose material, or may be present separately without being bound (it can also be said to be a composition containing the cellulose material). Iron components usually exist as iron atoms, compounds and derivatives containing iron atoms. Examples of these include iron atoms (Fe), oxides (Fe ₂ O ₃ , Fe ₃ O ₄ ), hydroxides (Fe(OH) ₂ , Fe(OH) ₃ ), oxyhydroxides (FeO( OH)), chlorides (FeCl ₂ , FeCl ₃ ), nitrates (Fe(NO) ₃ ), sulfates (FeSO ₄ , Fe ₂ (SO ₄ ) ₃ ), halides (Br, I), and complex compounds. The main component is usually an oxide.

As used herein, the iron component content is a value detected by a triple quadrupole-inductively coupled plasma (ICP) mass spectrometer. Specifically, it can be measured under the following conditions, and the values in Examples are also the values measured by the following method. Note that when the iron component is other than iron atoms, the amount of iron component represents the amount of iron atoms.
Model: Agilent 8800 (manufactured by Agilent Technologies Co., Ltd.)
Collision and reaction cell introduced gas: Helium and hydrogen Measurement m/z: Iron; 56
Internal standard element m/z: rhodium; 103

The amount of iron component in the cellulose material is usually 1 ppm or more, preferably 1.3 ppm or more or 1.5 ppm or more, more preferably 1.6 ppm or more or 1.7 ppm or more. Thereby, the effect of containing the iron component can be efficiently exhibited. The upper limit is usually 50 ppm or less, preferably 40 ppm or less, more preferably 29 ppm or less, 28 ppm or less, 27 ppm or less, or 26 ppm or less. Thereby, it is possible to suppress the contamination of foreign matter into the resin during recycling. Therefore, the amount of iron component is usually 1 to 50 ppm, preferably 1.3 to 40 ppm, more preferably 1.5 to 29 ppm, 1.5 to 28 ppm, 1.6 to 27 ppm, or 1.7 to 26 ppm. be.

The amount of iron component in the cellulose material is usually more than 10 ppm, preferably 10.5 ppm or more, more preferably 11 ppm or more, so that the thermogravimetric residual rate is high and the recyclability of the biomass material when mixed with resin is improved. An excellent cellulose material can be obtained. In this case, the upper limit is usually 50 ppm or less, preferably 40 ppm or less, more preferably 30 ppm or less, still more preferably 29 ppm or less, 28 ppm or less, 27 ppm or less, or 26 ppm or less. Thereby, it is possible to suppress the contamination of foreign matter into the resin during recycling. Therefore, the iron component content of the cellulose material is usually more than 10 ppm and less than 50 ppm, more preferably more than 10 ppm and less than 40 ppm, still more preferably 10.5 to 30 ppm, even more preferably 11 to 29 ppm, 11 to 28 ppm. , 11 to 27 ppm, or 11 to 26 ppm.

The amount of iron component in the cellulose material is usually 1 ppm or more, preferably 1.3 ppm or more, more preferably 1.5 ppm or more, 1.6 ppm or more, or 1.7 ppm or more, so that the thermogravimetric residual rate is high, It can improve the recyclability of biomass materials when mixed with resin, and prevents the frictional force on the tablet surface from becoming excessively strong when tabletting cellulose materials (e.g., powdered cellulose), making them less likely to break. You can get tablets. The upper limit is usually 10 ppm or less, preferably 7 ppm or less, more preferably 5 ppm or less, still more preferably 4 ppm or less, 3.8 ppm or less, 3.6 ppm or less, or 3.5 ppm or less. Thereby, the powdered cellulose can be made into tablets. Therefore, the iron content of the powdered cellulose is preferably 1 to 10 ppm, more preferably 1 to 7 ppm, even more preferably 1.3 to 5 ppm, even more preferably 1.5 to 4 ppm, and 1.6 to 3 ppm. .8 ppm, 1.7 to 3.6 ppm, or 1.7 to 3.5 ppm.

The amount of iron component can be adjusted by the amount of iron component contained in the raw material and the amount of iron component mixed during manufacturing.

[1.2. Ash content after heating〕
Preferably, the cellulosic material contains ash after heating at 800°C for 2 hours. Ash is usually a component other than organic matter that remains after the raw material is ashed. The ash content after heating is usually 0.05% by weight or more, preferably 0.07% by weight or more, based on 100% by weight of the cellulose material before heating. This makes it possible to obtain a cellulose material with a high thermogravimetric residual rate and excellent recyclability of the biomass material when mixed with resin. The upper limit is usually 2.0% by weight or less, preferably 1.6% by weight. Thereby, it is possible to suppress the contamination of foreign matter into the resin during recycling. Therefore, the ash content is usually 0.05 to 2.0% by weight, preferably 0.07 to 1.6% by weight.

When the amount of iron component in the cellulose material is more than 10 ppm and less than 50 ppm, the ash content after heating is preferably 0.13% by weight or more or 0.14% by weight based on 100% by weight of the cellulose material before heating. The content is more preferably 0.15% by weight or more. This makes it possible to obtain a cellulose material with a high thermogravimetric residual rate and excellent recyclability of the biomass material when mixed with resin. The upper limit is preferably 2.0% by weight or less, more preferably 1.6% by weight or less. Thereby, it is possible to suppress the contamination of foreign matter into the resin during recycling. Therefore, the ash content is preferably 0.13 to 2.0% by weight or 0.14 to 2.0% by weight, more preferably 0.15 to 1.6% by weight.

When the cellulose material is powdered cellulose and the amount of iron component is 10 ppm or less, the ash content after heating is preferably 1.0% by weight or less or 0.5% by weight based on 100% by weight of the powdered cellulose before heating. It is 5% by weight or less, more preferably 0.3% by weight or less or 0.15% by weight or less. Thereby, the powdered cellulose can be made into tablets. The lower limit is preferably 0.05% by weight or more or 0.07% by weight or more, more preferably 0.09% by weight or more. As a result, it is possible to obtain powdered cellulose that has a high thermogravimetric residual rate and excellent recyclability as a biomass material when mixed with resin, and when the powdered cellulose is made into tablets, there is no excessive frictional force on the tablet surface. It is possible to prevent tablets from becoming hard and hard to break. Therefore, the ash content is preferably 0.05 to 1.0% by weight or 0.07 to 0.5% by weight, more preferably 0.09 to 0.3% by weight or 0.09 to 0.15% by weight. It is.

The amount of ash after heating at 800 ° C. for 2 hours can be determined by, for example, carbonizing a sample (measure the sample weight in advance), heating it at 800 ° C. for 2 hours to incinerate it, and measuring the weight of the residue after ashing. It can be measured by calculating the ratio (%) of the ash residue to the sample weight.

[1.3. Thermogravimetric residual rate]
Cellulose materials can exhibit a high thermogravimetric survival rate. For example, the thermogravimetric residual rate after heating at 500°C is usually 6% or more, 7% or more, or 10% or more, preferably 10.5% or more, more preferably 11% or more. The upper limit is preferably 35% or less, more preferably 30% or less. To give another example, the thermogravimetric residual rate after heating at 400° C. is usually 8% or more, 9% or more, or 10% or more. The upper limit is usually 20% or less, or 18% or less, preferably 16% or less, or 15% or less, more preferably 13% or less. When the amount of iron component in the cellulose material is more than 10 ppm and less than 50 ppm, it is preferable that the thermogravimetric residual rate after heating at 500° C. satisfies the above range. When the amount of iron component in the cellulose material is 10 ppm or less, it is preferable that the thermogravimetric residual rate after heating at 400°C satisfies the above range, and when the cellulose material is powdered cellulose, the thermogravimetric residual rate after heating at 400°C It is more preferable that the residual rate satisfies the above range. The thermogravimetric residual rate after heating at 500°C or 400°C can be confirmed using a thermal analyzer as the ratio (%) of the weight after heating at 500°C or 400°C to the weight before the start of heating.

[1.4. Form of cellulose material]
Examples of the form of the cellulose material include powder and fibrous forms (microfibrils and nanofibers), with powdered cellulose being preferred.

[1.5. Powdered cellulose]
[Particle size distribution]
The particle size distribution of powdered cellulose is the particle size distribution when the integrated value of the volume accumulation distribution is 10%, 50%, and 90% (10% diameter, 50% diameter, 90% diameter, respectively, D.10, D.50, D.90). In this specification, the particle size distribution is a value obtained by wet measurement (with ultrasonic irradiation), wet measurement (without ultrasonic irradiation), or dry measurement using a laser scattering method as the measurement principle.

The span of the particle size distribution is determined by the D. 10,D. 50, D. It is calculated by substituting 90 into the following formula (1).
Formula (1): Span of particle size distribution = ((D.90)-(D.10))/(D.50)

-Conditions for wet measurement (no ultrasonic irradiation)-
In this specification, wet conditions (no ultrasonic irradiation) refer to conditions in which the particle diameter is directly measured without ultrasonic irradiation after adding water to the sample. D under wet conditions (no ultrasonic irradiation). 10,D. 50, D. 90, the preferred range of span is as follows. Generally, the larger the particle size, the more entangled the fibers tend to be. Further, within the following range, when added to resins, rubbers, etc., the strength can be appropriately improved without impairing their properties. Further, when the amount of iron component is 1 to 10 ppm, in addition to the above properties, it can exhibit good tabletability.

D. 10 is usually 5.0 μm or more, preferably 9.0 μm or more, more preferably 10.0 μm or more, even more preferably 11.0 μm or more. The upper limit is usually 40.0 μm or less, preferably 25.0 μm or less, more preferably 23.0 μm or less, even more preferably 22.0 μm or less. Therefore, it is usually 5.0 to 40.0 μm, preferably 9.0 to 25.0 μm, more preferably 10.0 to 23.0 μm, and still more preferably 11.0 to 22.0 μm.

If the amount of iron component in powdered cellulose exceeds 10 ppm and is 50 ppm, D. 10 is usually 5.0 μm or more, 9.0 μm or more, or 10.0 μm or more, preferably 11.0 μm or more, more preferably 11.5 μm or more, preferably 12.0 μm or more, more preferably 13.0 μm or more. be. The upper limit is usually 40.0 μm or less or 25.0 μm or less, preferably 23.0 μm or less or 22.0 μm or less, preferably 14.0 μm or less, more preferably 13.0 μm or less. Therefore, typically 5.0 to 40.0 μm, 9.0 to 40.0 μm, or 10.0 to 25.0 μm, preferably 12.0 to 23.0 μm, 13.0 to 22.0 μm, or 11. It is 0 to 14.0 μm, more preferably 11.5 to 13.0 μm.

When the amount of iron component in powdered cellulose is 1 to 10 ppm, D. 10 is usually 5.0 μm or more, 9.0 μm or more, or 10.0 μm or more, preferably 12.0 μm or more, more preferably 13.0 μm or more. The upper limit is usually 40.0 μm or less or 25.0 μm or less, preferably 23.0 μm or less, and more preferably 22.0 μm or less. Therefore, it is usually 5.0 to 40.0 μm, 9.0 to 40.0 μm, or 10.0 to 25.0 μm, preferably 12.0 to 23.0 μm, more preferably 13.0 to 22.0 μm. be.

D. 50 (average particle diameter) is usually 5.0 μm or more, 10.0 μm or more, preferably 20.0 μm or more, or 25.0 μm or more, more preferably 30.0 μm or more, or 34.0 μm or more, even more preferably It is 36.0 μm or more, or 38.0 μm or more (however, it is a value larger than D.10). Thereby, it is possible to suppress an increase in the cohesiveness of the powdered cellulose and a decrease in powder fluidity due to this, and it is possible to suppress deterioration in workability. The upper limit is usually 150.0 μm or less, 140.0 μm or less, or 130.0 μm or less, preferably 120.0 μm or less, or 110.0 μm or less, more preferably 100.0 μm or less, or 90.0 μm or less, even more preferably is 80.0 μm or less, 75.0 μm or less, or 70.0 μm or less. Thereby, powdered cellulose having a high thermogravimetric residual rate and excellent recyclability can be obtained. Therefore, D. 50 (average particle diameter) is usually 5.0 to 150.0 μm, 5.0 to 140.0 μm, 10.0 to 130.0 μm, 10.0 to 120.0 μm, 20.0 to 110.0 μm, 20.0 to 100.0 μm, 25.0 to 90.0 μm, 30.0 to 80.0 μm, 34.0 to 80.0 μm, 36.0 to 75.0 μm, and 38.0 to 70.0 μm.

If the amount of iron component in powdered cellulose exceeds 10 ppm and is 50 ppm, D. 50 (average particle diameter) is usually 5.0 μm or more, 10.0 μm or more, 20.0 μm or more, or 25.0 μm or more, preferably 30.0 μm or more or 34.0 μm or more, more preferably 36.0 μm or more, More preferably, it is 38.0 μm or more (however, it is a value larger than D.10). Thereby, it is possible to suppress an increase in the cohesiveness of the powdered cellulose and a decrease in powder fluidity due to this, and it is possible to suppress deterioration in workability. The upper limit is usually 150.0 μm or less, 100.0 μm or less, 90.0 μm or less, 70.0 μm or less, or 50.0 μm or less, preferably 45.0 μm or less, 44.0 μm or less, or 43.0 μm or less, more preferably It is 42.0 μm or less, more preferably 40.0 μm or less. Thereby, powdered cellulose having a high thermogravimetric residual rate and excellent recyclability can be obtained. Therefore, D. 50 (average particle diameter) is usually 5.0 to 150.0 μm, 5.0 to 100.0 μm, 10.0 to 90.0 μm, 20.0 to 70.0 μm or 25.0 to 50.0 μm, Preferably it is 30.0 to 45.0 μm, 30.0 to 44.0 μm or 34.0 to 43.0 μm, more preferably 36.0 to 42.0 μm, still more preferably 38.0 to 40.0 μm.

When the amount of iron component in powdered cellulose is 1 to 10 ppm, D. 50 (average particle diameter) is usually 5.0 μm or more, 10.0 μm or more, 20.0 μm or more, or 25.0 μm or more, preferably 30.0 μm or more or 34.0 μm or more, more preferably 38.0 μm or more, More preferably, it is 40.0 μm or more (however, it is a value larger than D.10). Thereby, it is possible to suppress an increase in the cohesiveness of the powdered cellulose and a decrease in powder fluidity due to this, and it is possible to suppress deterioration in workability. The upper limit is usually 150.0 μm or less, 140.0 μm or less, 130.0 μm or less, 120.0 μm or less, or 110.0 μm or less, preferably 100.0 μm or less, 90.0 μm or less, or 80.0 μm or less, more preferably It is 75.0 μm or less, more preferably 70.0 μm or less. Thereby, powdered cellulose having a high thermogravimetric residual rate and excellent recyclability can be obtained. Therefore, D. 50 (average particle diameter) is usually 5.0 to 150.0 μm, 5.0 to 140.0 μm, 10.0 to 130.0 μm, 20.0 to 120.0 μm or 25.0 to 110.0 μm, Preferably 30.0 to 100.0 μm, 30.0 to 90.0 μm or 34.0 to 80.0 μm, more preferably 38.0 to 75.0 μm, still more preferably 40.0 to 70.0 μm.

D. 90 is usually 70.0 μm or more or 75.0 μm or more, preferably 80.0 μm or more, 85.0 μm or more, or 90.0 μm or more, more preferably 95.0 μm or more, still more preferably 100.0 μm or more, 105. It is 0 μm or more, or 110.0 μm or more (however, it is a value larger than D.50). The upper limit is usually 250.0 μm or less, or 240.0 μm or less, preferably 230.0 μm or less, or 225.0 μm or less, more preferably 220.0 μm or less, or 215.0 μm or less, even more preferably 210.0 μm or less. It is. Therefore, typically 70.0 to 250.0 μm, 75.0 to 250.0 μm, 80.0 to 240.0 μm, 85.0 to 240.0 μm, or 90.0 to 230.0 μm, preferably 95.0 μm. -225.0 μm, 100.0-220.0 μm, 105.0-215.0 μm, and 110.0-210.0 μm.

If the amount of iron component in powdered cellulose exceeds 10 ppm and is 50 ppm, D. 90 is usually 70.0 μm or more or 75.0 μm or more, preferably 80.0 μm or more, 85.0 μm or more, or 90.0 μm or more, more preferably 95.0 μm or more, and still more preferably 100.0 μm or more ( However, the value is larger than D.50). The upper limit is usually 250.0 μm or less, 230.0 μm or less, or 220.0 μm or less, preferably 210.0 μm or less or 200.0 μm or less, more preferably 195.0 μm or less, and even more preferably 190.0 μm or less. . Therefore, usually 70.0 to 250.0 μm, 70.0 to 230.0 μm, or 75.0 to 220.0 μm, preferably 80.0 to 210.0 μm, 85.0 to 200.0 μm, or 90.0 μm. -200.0 μm, more preferably 95.0-195.0 μm, still more preferably 100.0-190.0 μm.

When the amount of iron component in powdered cellulose is 1 to 10 ppm, D. 90 is usually 70.0 μm or more or 80.0 μm or more, preferably 90.0 μm or more, 95.0 μm or more, or 100.0 μm or more, more preferably 105.0 μm or more, and still more preferably 110.0 μm or more ( However, the value is larger than D.50). The upper limit is usually 250.0 μm or less, 240.0 μm or less, or 230.0 μm or less, preferably 225.0 μm or less or 220.0 μm or less, more preferably 215.0 μm or less, and still more preferably 210.0 μm or less. . Therefore, usually 70.0 to 250.0 μm, 70.0 to 240.0 μm, or 80.0 to 230.0 μm, preferably 90.0 to 225.0 μm, 95.0 to 220.0 μm, or 100.0 μm. -220.0 μm, more preferably 105.0-215.0 μm, even more preferably 110.0-210.0 μm.

The span of the particle size distribution is usually 1.5 or more, preferably 1.7 or more, more preferably 1.9 or more, and still more preferably 2.0 or more. The upper limit is usually 6.0 or less, preferably 5.5 or less, more preferably 5.0 or less, still more preferably 4.5 or less. Therefore, usually 1.5 to 6.0, or 1.7 to 6.0, preferably 1.9 to 5.5, more preferably 1.9 to 5.0, or 2.0 to 5.0 , more preferably from 2.0 to 4.5.

When the amount of iron component in powdered cellulose exceeds 10 ppm and is 50 ppm, the span of the particle size distribution is usually 1.5 or more, preferably 1.7 or more, more preferably 1.9 or more, and even more preferably 2. .0 or more. The upper limit is usually 6.0 or less, preferably 5.5 or less, more preferably 5.0 or less, still more preferably 4.5 or less. Therefore, it is usually 1.5 to 6.0, preferably 1.7 to 5.5, more preferably 1.9 to 5.0, and even more preferably 2.0 to 4.5.

When the amount of iron component in powdered cellulose is 1 to 10 ppm, the span of the particle size distribution is usually 2.1 or more, preferably 2.2 or more, more preferably 2.3 or more, and still more preferably 2.4. That's all. The upper limit is usually 6.0 or less, preferably 5.0 or less, more preferably 4.0 or less, and even more preferably 3.0 or less. Therefore, it is usually 2.1 to 6.0, preferably 2.2 to 5.0, more preferably 2.3 to 4.0, and even more preferably 2.4 to 3.0.

-Wet measurement (with ultrasonic irradiation)-
In this specification, wet conditions (with ultrasonic irradiation) refer to conditions in which a sample is subjected to ultrasonic irradiation after being hydrated, and then the particle diameter is measured. D. for wet type (with ultrasonic waves) 10,D. 50, D. 90, the preferred range of span is as follows. Generally, the larger the particle size, the more entangled the fibers tend to be. Further, within the following range, when added to resins, rubbers, etc., the strength can be appropriately improved without impairing their properties. Further, when the amount of iron component is 1 to 10 ppm, in addition to the above properties, it can exhibit good tabletability.

D. 10 is usually 1.0 μm or more, or 3.0 μm or more, preferably 5.0 μm or more, or 9.0 μm or more, more preferably 9.5 μm or more, or 10.0 μm or more, and even more preferably 10.5 μm. That's all. The upper limit is usually 24.0 μm or less, preferably 23.0 μm or less, more preferably 22.5 μm or less, still more preferably 22.0 μm or less. Therefore, usually 1.0 to 24.0 μm, or 3.0 to 24.0 μm, preferably 5.0 to 23.0 μm, or 9.0 to 23.0 μm, more preferably 9.5 to 22 .5 μm, or 10.0 to 22.5 μm, more preferably 10.5 to 22.0 μm.

If the amount of iron component in powdered cellulose exceeds 10 ppm and is 50 ppm, D. 10 is usually 1.0 μm or more, 3.0 μm or more, or 5.0 μm or more, preferably 9.0 μm or more or 10.0 μm or more, more preferably 10.5 μm or more, and still more preferably 11.0 μm or more. The upper limit is usually 20.0 μm or less or 16.0 μm or less, preferably 13.0 μm or less, and more preferably 12.5 μm or less. Therefore, usually 1.0 to 20.0 μm, 3.0 to 16.0 μm or 5.0 to 16.0 μm, preferably 9.0 to 13.0 μm or 10.0 to 13.0 μm, more preferably 10 .5 to 12.5 μm, more preferably 11.0 to 12.5 μm.

When the amount of iron component in powdered cellulose is 1 to 10 ppm, D. 10 is usually 1.0 μm or more, 3.0 μm or more, or 5.0 μm or more, preferably 9.0 μm or more or 9.5 μm or more, more preferably 10.0 μm or more, still more preferably 10.5 μm or more. The upper limit is usually 24.0 μm or less or 23.0 μm or less, preferably 22.5 μm or less, and more preferably 22.0 μm or less. Therefore, usually 1.0 to 24.0 μm, 3.0 to 23.0 μm or 5.0 to 23.0 μm, preferably 9.0 to 22.5 μm or 9.5 to 22.5 μm, more preferably 10 .0 to 22.0 μm, more preferably 10.5 to 22.0 μm.

D. 50 is usually 5.0 μm or more, or 10.0 μm or more, preferably 20.0 μm or more, or 23.0 μm or more, more preferably 25.0 μm or more, or 26.0 μm or more, still more preferably 27 .0 μm or more, 27.5 μm or more, or 28.0 μm or more (however, the value is larger than D.10). The upper limit is usually 150.0 μm or less, preferably 120.0 μm or less, more preferably 100.0 μm or less, still more preferably 80.0 μm or less, or 70.0 μm or less. Therefore, usually 5.0 to 150.0 μm, 10.0 to 150.0 μm, or 20.0 to 150.0 μm, preferably 23.0 to 120.0 μm, 25.0 to 120.0 μm, 26.0 to 100.0 μm, 27.0 to 100.0 μm, 27.5 to 80.0 μm, or 28.0 to 70.0 μm.

If the amount of iron component in powdered cellulose exceeds 10 ppm and is 50 ppm, D. 50 is usually 5.0 μm or more, 10.0 μm or more, or 20.0 μm or more, preferably 25.0 μm or more, 30.0 μm or more, or 32.0 μm or more, more preferably 34.0 μm or more or 36.0 μm or more, More preferably, it is 36.5 μm or more (however, the value is larger than D.10). The upper limit is usually 70.0 μm or less, 60.0 μm or less, or 50.0 μm or less, preferably 45.0 μm or less or 40.0 μm or less, more preferably 39.5 μm or less, still more preferably 39.0 μm or less. Therefore, usually 5.0 to 70.0 μm, 10.0 to 60.0 μm or 20.0 to 50.0 μm, preferably 25.0 to 45.0 μm, 30.0 to 40.0 μm or 32.0 to 40.0 μm, more preferably 34.0 to 39.5 μm, still more preferably 36.0 to 39.0 μm or 36.5 to 39.0 μm.

When the amount of iron component in powdered cellulose is 1 to 10 ppm, D. 50 is usually 5.0 μm or more, 10.0 μm or more, or 20.0 μm or more, preferably 23.0 μm or more, 25.0 μm or more, or 26.0 μm or more, more preferably 27.0 μm or more or 27.5 μm or more, More preferably, it is 28.0 μm or more (however, the value is larger than D.10). The upper limit is usually 150.0 μm or less, 120.0 μm or less, or 100.0 μm or less, preferably 80.0 μm or less or 70.0 μm or less, more preferably 69.5 μm or less, still more preferably 69.0 μm or less. Therefore, usually 5.0 to 150.0 μm, 10.0 to 120.0 μm or 20.0 to 100.0 μm, preferably 23.0 to 80.0 μm, 25.0 to 70.0 μm or 26.0 to 70.0 μm, more preferably 27.0 to 69.5 μm, even more preferably 27.5 to 69.0 μm or 28.0 to 69.0 μm.

D. 90 is usually 50.0 μm or more, 55.0 μm or more, 60.0 μm or more, 65.0 μm or more, 70.0 μm or more, 75.0 μm or more (however, it is a value larger than D.50). The upper limit is usually 230.0 μm or less, 225.0 μm or less, or 220.0 μm or less, preferably 215.0 μm or less, 210.0 μm or less. Therefore, D. 90 is usually 50.0 to 230.0 μm, 55.0 to 225.0 μm, 60.0 to 220.0 μm, 65.0 to 215.0 μm or 70.0 to 210.0 μm, preferably 75.0 ~200.0 μm, 80.0 to 215.0 μm, more preferably 90.0 to 215.0 μm, even more preferably 100.0 to 210.0 μm.

If the amount of iron component in powdered cellulose exceeds 10 ppm and is 50 ppm, D. 90 is usually 50.0 μm or more, 60.0 μm or more, 70.0 μm or more, or 90.0 μm or more, preferably 98.0 μm or more, more preferably 100.0 μm or more, even more preferably 101.5 μm or more ( However, the value is larger than D.50). The upper limit is usually 210.0 μm or less or 200.0 μm or less, preferably 200.0 μm or less, more preferably 195.0 μm or less, even more preferably 190.0 μm or less. Therefore, D. 90 is usually 50.0 to 210.0 μm, 60.0 to 200.0 μm or 70.0 to 200.0 μm, preferably 80.0 to 195.0 μm, more preferably 90.0 to 190.0 μm, More preferably, it is 100.0 to 190.0 μm.

When the amount of iron component in powdered cellulose is 1 to 10 ppm, D. 90 is usually 50.0 μm or more, 55.0 μm or more, or 60.0 μm or more, preferably 65.0 μm or more, more preferably 70.0 μm or more, even more preferably 75.0 μm or more (however, D.50 ). The upper limit is usually 230.0 μm or less or 225.0 μm or less, preferably 220.0 μm or less, more preferably 215.0 μm or less, even more preferably 210.0 μm or less. Therefore, D. 90 is usually 50.0 to 230.0 μm, 55.0 to 225.0 μm or 60.0 to 225.0 μm, preferably 65.0 to 220.0 μm, more preferably 70.0 to 215.0 μm, More preferably, it is 75.0 to 210.0 μm.

The span of the particle size distribution is usually 1.5 or more, preferably 1.7 or more, more preferably 1.9 or more, and still more preferably 2.0 or more. The upper limit is usually 5.0 or less, preferably 4.5 or less. Therefore, it is usually 1.5 to 5.0, preferably 1.7 to 5.0, more preferably 1.9 to 5.0, or 2.0 to 4.5.

When the amount of iron component in powdered cellulose exceeds 10 ppm and is 50 ppm, the span of the particle size distribution is usually 1.5 or more, preferably 1.7 or more, more preferably 1.9 or more, and even more preferably 2. .0 or more. The upper limit is usually 5.0 or less, preferably 4.5 or less. Therefore, it is usually 1.5 to 5.0, preferably 1.7 to 4.5, more preferably 1.9 to 4.5, or 2.0 to 4.5.

When the amount of iron component in the powdered cellulose is 1 to 10 ppm, the span of the particle size distribution is usually 1.5 or more, preferably 1.7 or more, more preferably 2.0 or more, and even more preferably 2.2. That's all. The upper limit is usually 5.0 or less, preferably 3.5 or less, more preferably 2.9 or less. Therefore, it is usually 1.5 to 5.0, preferably 2.0 to 3.5, and more preferably 2.2 to 2.9.

-Dry measurement-
In this specification, dry measurement refers to conditions in which the particle diameter is directly measured without adding water to the sample. D. for dry measurement. 10,D. 50, D. 90, the preferred range of span is as follows. Generally, the larger the particle size, the more entangled the fibers tend to be. Further, within the following range, when added to resins, rubbers, etc., the strength can be appropriately improved without impairing their properties. Further, when the amount of iron component is 1 to 10 ppm, in addition to the above properties, it can exhibit good tabletability.

D. 10 is usually 1.0 μm or more, 3.0 μm or more, or 5.0 μm or more, preferably 7.0 μm or more or 8.0 μm or more, more preferably 9.0 μm or more, or 9.5 μm or more. The upper limit is usually 40.0 μm or less, 35.0 μm or less, or 30.0 μm or less, preferably 27.0 μm or less, 26.0 μm or less. Therefore, usually 1.0 to 40.0 μm, 3.0 to 40.0 μm or 5.0 to 35.0 μm, preferably 7.0 to 35.0 μm, 8.0 to 30.0 μm, or 9.0 μm -27.0 μm, more preferably 9.5-26.0 μm.

If the amount of iron component in powdered cellulose exceeds 10 ppm and is 50 ppm, D. 10 is usually 1.0 μm or more, 3.0 μm or more, or 5.0 μm or more, preferably 7.0 μm or more or 8.0 μm or more, more preferably 9.0 μm or more, and still more preferably 9.5 μm or more. The upper limit is usually 40.0 μm or less or 20.0 μm or less, preferably 15.0 μm or less, more preferably 14.0 μm or less, even more preferably 13.0 μm or less. Therefore, usually 1.0 to 40.0 μm, 3.0 to 20.0 μm or 5.0 to 20.0 μm, preferably 7.0 to 15.0 μm or 8.0 to 15.0 μm, more preferably 9 .0 to 14.0 μm, more preferably 9.5 to 13.0 μm.

When the amount of iron component in powdered cellulose is 1 to 10 ppm, D. 10 is usually 1.0 μm or more, 3.0 μm or more, or 5.0 μm or more, preferably 7.0 μm or more or 10.0 μm or more, more preferably 13.0 μm or more, and still more preferably 13.5 μm or more. The upper limit is usually 40.0 μm or less or 35.0 μm or less, preferably 30.0 μm or less, more preferably 27.0 μm or less, even more preferably 26.0 μm or less. Therefore, usually 1.0 to 40.0 μm, 3.0 to 35.0 μm or 5.0 to 35.0 μm, preferably 7.0 to 30.0 μm or 10.0 to 30.0 μm, more preferably 13 0 to 27.0 μm, more preferably 13.5 to 26.0 μm.

D. 50 is usually 5.0 μm or more, 10.0 μm or more, or 15.0 μm or more, preferably 20.0 μm or more, 25.0 μm or more, or 30.0 μm or more, more preferably 33.0 μm or more, 34.0 μm or more, or 35.0 μm or more (however, the value is larger than D.10). The upper limit is usually 150.0 μm or less, or 100.0 μm or less, preferably 90.0 μm or less, more preferably 88.0 μm or less, even more preferably 87.0 μm or less. Therefore, D. 50 is usually 5.0 to 150.0 μm, 10.0 to 150.0 μm or 15.0 to 100.0 μm, preferably 20.0 to 100.0 μm, 25.0 to 90.0 μm or 30.0 μm. -90.0 μm, more preferably 33.0-88.0 μm or 34.0-88.0 μm, even more preferably 35.0-87.0 μm.

If the amount of iron component in powdered cellulose exceeds 10 ppm and is 50 ppm, D. 50 is usually 5.0 μm or more, 10.0 μm or more, or 15.0 μm or more, preferably 20.0 μm or more, 25.0 μm or more, or 30.0 μm or more, more preferably 33.0 μm or more, 34.0 μm or more, More preferably, it is 35.0 μm or more (however, the value is larger than D.10). The upper limit is usually 100.0 μm or less or 60.0 μm or less, preferably 52.5 μm or less or 52.0 μm or less, more preferably 51.5 μm or less. Therefore, D. 50 is usually 5.0 to 100.0 μm, 10.0 to 60.0 μm or 15.0 to 60.0 μm, preferably 20.0 to 52.5 μm, 25.0 to 52.5 μm or 30.0 ~52.5μm, more preferably 33.0~52.0μm or 34.0~52.0μm, still more preferably 35.0~51.5μm.

When the amount of iron component in powdered cellulose is 1 to 10 ppm, D. 50 is usually 5.0 μm or more, 10.0 μm or more, or 15.0 μm or more, preferably 25.0 μm or more, 30.0 μm or more, or 35.0 μm or more, more preferably 40.0 μm or more or 41.0 μm or more, More preferably, it is 41.5 μm or more (however, it is a value larger than D.10). The upper limit is usually 150.0 μm or less or 100.0 μm or less, preferably 90.0 μm or less or 88.0 μm or less, more preferably 87.0 μm or less. Therefore, D. 50 is usually 5.0 to 150.0 μm, 10.0 to 100.0 μm or 15.0 to 100.0 μm, preferably 25.0 to 90.0 μm, 30.0 to 90.0 μm or 35.0 -90.0 μm, more preferably 40.0-88.0 μm or 41.0-88.0 μm, even more preferably 41.5-87.0 μm.

D. 90 is usually 80.0 μm or more, preferably 90.0 μm or more, more preferably 93.0 μm or more, even more preferably 94.0 μm or more (however, it is a value larger than D.50) . The upper limit is usually 330.0 μm or less, preferably 320.0 μm or less, more preferably 315.0 μm or less, or 310.0 μm or less, still more preferably 305.0 μm or less. Therefore, D. 90 is usually 80.0 to 330.0 μm, preferably 80.0 to 320.0 μm, more preferably 90.0 to 315.0 μm, or 93.0 to 310.0 μm, still more preferably 94 .0 to 305.0 μm.

If the amount of iron component in powdered cellulose exceeds 10 ppm and is 50 ppm, D. 90 is usually 80.0 μm or more, or 90.0 μm or more, preferably 93.0 μm or more, more preferably 94.0 μm or more (however, it is a value larger than D.50). The upper limit is usually 310.0 μm or less or 280.0 μm or less, preferably 260.0 μm or less or 255.0 μm, more preferably 251.0 μm or less. Therefore, D. 90 is usually 80.0 to 310.0 μm or 90.0 to 280.0 μm, preferably 93.0 to 260.0 μm or 93.0 to 255.0 μm, more preferably 94.0 to 251.0 μm. be.

When the amount of iron component in powdered cellulose is 1 to 10 ppm, D. 90 is usually 90.0 μm or more or 110.0 μm or more, preferably 120.0 μm or more, more preferably 130.0 μm or more (however, it is a value larger than D.50). The upper limit is usually 330.0 μm or less or 320.0 μm or less, preferably 315.0 μm or less or 310.0 μm or less, more preferably 305.0 μm or less. Therefore, D. 90 is usually 90.0 to 330.0 μm or 110.0 to 320.0 μm, preferably 120.0 to 315.0 μm or 120.0 to 310.0 μm, more preferably 130.0 to 305.0 μm. be.

The span of the particle size distribution is usually 1.5 or more, preferably 1.7 or more, more preferably 1.8 or more, still more preferably 2.0 or more. The upper limit is usually 9.0 or less, preferably 7.0 or less, more preferably 6.0 or less, even more preferably 5.0 or less. Therefore, the span of the particle size distribution is usually 1.5 to 9.0, preferably 1.7 to 7.0, more preferably 1.8 to 6.0, even more preferably 2.0 to 5.0. It is.

When the amount of iron component in powdered cellulose exceeds 10 ppm and is 50 ppm, the span of the particle size distribution is usually 1.5 or more, preferably 1.7 or more, more preferably 1.8 or more, and still more preferably 2. .0 or more. The upper limit is usually 9.0 or less, preferably 7.0 or less, more preferably 6.0 or less, still more preferably 5.0 or less. Therefore, the span of the particle size distribution is usually 1.5 to 9.0, preferably 1.7 to 7.0, more preferably 1.8 to 6.0, even more preferably 2.0 to 5.0. It is.

When the amount of iron component in powdered cellulose is 1 to 10 ppm, the span of the particle size distribution is usually 2.5 or more, preferably 2.6 or more, more preferably 2.7 or more, and still more preferably 2.8. That's all. The upper limit is usually 7.0 or less, preferably 6.0 or less, more preferably 5.0 or less, still more preferably 4.0 or less. Therefore, the span of the particle size distribution is usually 2.5 to 7.0, preferably 2.6 to 6.0, more preferably 2.7 to 5.0, even more preferably 2.8 to 4.0. It is.

[Average fiber width (μm), average fiber length (mm), average fiber length/average fiber width]
The average fiber width (minor axis) refers to the average value of the minimum value orthogonal to the major axis of the fiber width of powdered cellulose. Moreover, the average fiber length (length axis) refers to the average value of the maximum length of the fiber width of powdered cellulose.

The average fiber width is usually 10 μm or more, preferably 15 μm or more, and more preferably 20 μm or more. The upper limit is usually 40 μm or less, preferably 35 μm or less, more preferably 33 μm or less, still more preferably 32 μm or less. Therefore, the average fiber width is usually 10 to 40 μm, preferably 10 to 35 μm or 10 to 24 μm, more preferably 15 to 33 μm, and still more preferably 20 to 32 μm.

When the amount of iron component in the powdered cellulose is more than 10 ppm and 50 ppm, the average fiber width is preferably 10 μm or more, more preferably 15 μm or more, and still more preferably 20 μm or more. The upper limit is preferably 35 μm or less, more preferably 30 μm or less, even more preferably 24 μm or less. Therefore, the average fiber width is preferably 10 to 35 μm or 10 to 24 μm, more preferably 15 to 30 μm, even more preferably 20 to 24 μm.

When the amount of iron component in the powdered cellulose is 1 to 10 ppm, the average fiber width is usually 10 μm or more, preferably 20 μm or more, more preferably 24 μm or more, and still more preferably 24.5 μm or more. The upper limit is usually 40 μm or less, preferably 35 μm or less, more preferably 33 μm or less, even more preferably 32 μm or less. Therefore, the average fiber width is usually 10 to 40 μm, preferably 20 to 35 μm, more preferably 24 to 33 μm, and still more preferably 24.5 to 32 μm.

The average fiber length is usually 0.03 mm or more, preferably 0.05 mm or more. The upper limit is usually 0.3 mm or less, preferably 0.25 mm or less, more preferably 0.2 mm or less. Therefore, the average fiber length is usually 0.03 to 0.3 mm, preferably 0.05 to 0.25, and more preferably 0.05 to 0.2 mm.

When the amount of iron component in the powdered cellulose is more than 10 ppm and 50 ppm, the average fiber length is preferably 0.05 mm or more, more preferably 0.06 mm or more. The upper limit is preferably 0.3 mm or less, more preferably 0.25 mm or less. Therefore, the average fiber length is preferably 0.05 to 0.3 mm, more preferably 0.06 to 0.25 mm.

When the amount of iron component in the powdered cellulose is 1 to 10 ppm, the average fiber length is preferably 0.03 mm or more, more preferably 0.05 mm or more. The upper limit is preferably 0.3 mm or less, more preferably 0.2 mm or less. Therefore, the average fiber length is preferably 0.03 to 0.3 mm, more preferably 0.05 to 0.2 mm.

The average fiber length/average fiber width (L/D) of powdered cellulose is usually 2.0 or more, preferably 3.0 or more. The upper limit is usually 12.0 or less, preferably 11.5 or less. Therefore, L/D is usually 2.0 to 12.0, preferably 3.0 to 11.5.

When the amount of iron component in the powdered cellulose exceeds 10 ppm and is 50 ppm, L/D is preferably 2.5 to 12.0, more preferably 3.0 to 11.5. Generally, the larger the L/D, the more entangled the fibers tend to be. Furthermore, within the above range, when added to resins, rubbers, etc., the strength can be appropriately improved without impairing their properties.

When the amount of iron component in powdered cellulose is 1 to 10 ppm, L/D is preferably 3.0 to 8.0, more preferably 3.0 to 7.0, and still more preferably 3.0 to 8.0. It is 0 to 6.0. Generally, the larger the L/D, the more entangled the fibers tend to be. Further, within the above range, when added to resins, rubbers, etc., the strength can be appropriately improved without impairing their properties, and good suitability for tabletting can be exhibited.

The average fiber length and average fiber width can be measured using Fiber Tester Plus manufactured by ABB, and L/D is a value calculated from these measured values.

[1.6. fibrous cellulose]
Fibrous cellulose refers to cellulose fibers prepared through a micronization process and having a fiber diameter on the nano-order or micro-order. In this specification, they are respectively referred to as cellulose nanofibers (CNF) and cellulose microfibrils (MFC).

The average fiber diameter (length-weighted average fiber diameter) of CNF is 500 nm or less, preferably 300 nm or less, more preferably 100 nm or less, even more preferably 50 nm or less. Although the lower limit is not particularly limited, it is usually 1 nm or more, preferably 2 nm or more. Therefore, the average fiber diameter (length-weighted average fiber diameter) of CNF is usually 1 to 500 nm or 2 to 500 nm, preferably 2 to 300 nm or 2 to 100 nm, more preferably 2 to 50 nm or 3 to 30 nm. The average fiber length (length-weighted average fiber length) is usually 50 to 2000 nm, preferably 100 to 1000 nm. The aspect ratio of CNF is usually 10 or more, preferably 50 or more. The upper limit is not particularly limited, but is usually 1000 or less.

The average fiber diameter of MFC is usually 500 nm or more, preferably 1 μm or more, and more preferably 3 μm or more. As a result, it can exhibit higher water retention than undefibrated cellulose fibers, and even in a small amount, a high strength imparting effect and yield improvement effect can be obtained compared to finely defibrated CNF. The upper limit of the average fiber diameter is preferably 60 μm or less, more preferably 40 μm or less, even more preferably 30 μm or less, and even more preferably 20 μm or less, but there is no particular restriction. The average fiber length is usually 10 μm or more, 20 μm or more, or 40 μm or more, preferably 200 μm or more, 300 μm or more, or 400 μm or more, more preferably 500 μm or more or 550 μm or more, even more preferably 600 μm or more, 700 μm or more, or 800 μm. That's all. The upper limit is not particularly limited, but is usually 3,000 μm or less, preferably 2,500 μm or less, more preferably 2,000 μm or less, still more preferably 1,500 μm or less, 1,400 μm or less, or 1,300 μm. The aspect ratio of MFC is preferably 3 or more, more preferably 5 or more, even more preferably 7 or more, and may be 10 or more, 20 or more, or 30 or more. The upper limit of the aspect ratio is not particularly limited, but is preferably 1000 or less, more preferably 100 or less, and even more preferably 80 or less.

The average fiber diameter and average fiber length of fibrous cellulose can be determined using a fractionator manufactured by Valmet Corporation. When using a fractionator, it can be determined as length-weighted fiber width and length-weighted average fiber length, respectively. The average aspect ratio of fine cellulose fibers can be calculated by the formula: average aspect ratio=average fiber length/average fiber diameter.

The fibrous cellulose may be modified or unmodified. Modified fibrous cellulose refers to fine cellulose fibers (e.g., cellulose nanofibers, cellulose microfibrils) in which at least one of the three hydroxyl groups contained in the glucose unit has been chemically modified (hereinafter simply referred to as "modified"). ) means. Through the chemical modification treatment, cellulose fibers are sufficiently refined, and cellulose nanofibers having a uniform average fiber length and average fiber diameter can be obtained by defibration. Therefore, when compounded with a rubber component, it can exhibit a sufficient reinforcing effect. From this point of view, modified cellulose fibers are preferred.

Examples of modification include oxidation, etherification, esterification such as phosphoric acid esterification, silane coupling, fluorination, cationization, and the like. Among these, oxidation (carboxylation), etherification, cationization, and esterification are preferred, and oxidation (carboxylation) is more preferred.

[2. Manufacturing method of cellulose material]
The cellulose material is not particularly limited as long as it is obtained by a method of obtaining a cellulose material from a cellulose raw material. In the case of powdered cellulose, for example, a method including at least a pulverization treatment may be mentioned, and a method including a mechanical pulverization treatment is preferred. In the case of fibrous cellulose, for example, a method including defibration treatment can be mentioned.

[2.1. Cellulose raw material]
The cellulose raw material is usually naturally derived cellulose, preferably pulp, and more preferably pulp derived from wood. Examples of pulp derived from wood include pulp derived from broad-leaved trees and pulp derived from coniferous trees. Examples of methods for preparing wood-derived pulp include methods that include bleaching treatment. Bleaching treatment methods include, for example, chlorine treatment (C), chlorine dioxide bleaching (D), alkaline extraction (E), hypochlorite bleaching (H), Hydrogen peroxide bleaching (P), alkaline hydrogen peroxide treatment stage (Ep), alkaline hydrogen peroxide/oxygen treatment stage (Eop), ozone treatment (Z), chelation treatment (Q), and two or more of these treatments One example is a method of applying a combination. Examples of combinations (sequences) of two or more processes include D-E/P-D, C/D-E-HD, Z-E-D-PZ/D-Ep-D, and Z/D- Ep-DP, D-Ep-D, D-Ep-DP, D-Ep-PD, Z-Eop-DD, Z/D-Eop-D, Z/D-Eop- An example is DE (the "/" in the sequence means that the processes before and after the "/" are performed consecutively without washing). Bleaching treatment is not limited to the above example, and may be any commonly used method. Pulp that has undergone bleaching treatment is usually in a fluid state (fluid pulp). The whiteness of the pulp is preferably 80% or more based on ISO 2470.

An example of a method for preparing pulp is a pulping method (cooking method). The pulping method (cooking method) dissolves and removes the colored substance lignin, making it possible to obtain pulp with a high degree of whiteness. Examples of the pulping method (cooking method) include sulfite cooking, kraft cooking, soda quinone cooking, and organosolve cooking, with kraft pulp being preferred from an environmental standpoint. Mechanical pulps such as ground wood pulp (GP), refined ground wood pulp (RGP), thermomechanical pulp (TMP), and chemi-thermomechanical pulp (CTMP) can also be used.

The moisture content of the cellulose raw material is usually preferably 5 to 30%, preferably 6 to 20%, based on 100% of the cellulose raw material. When the moisture content of the cellulose raw material is higher than the above range, the moisture content may be adjusted by dehydration/drying treatment described below.

[2.2. Method for producing powdered cellulose]
[Mechanical crushing process]
The pulverization process is a process of mechanically pulverizing the cellulose raw material. Prior to the pulverization treatment, pretreatment such as dehydration/drying treatment, acid hydrolysis treatment, etc. may be performed, and dehydration/drying treatment is preferred. A classification process may be performed simultaneously with the pulverization process or after the pulverization process.

Examples of the crusher include a cutting type mill, an impact type mill, an air flow type mill, a hammer type mill, a roll mill, a roller mill, a media mill, a media stirring mill, a vibration mill, and a freeze crusher. Two or more types may be used in combination.

Examples of cutting-type mills include cutting mills (manufactured by Horai Co., Ltd.), mesh mills (manufactured by Horai Co., Ltd.), Atoms (manufactured by Yamamoto Hyakuma Seisakusho Co., Ltd.), knife mills (manufactured by Palman Co., Ltd.), and cutter mills (manufactured by Tokyo Atomizer Co., Ltd.). (manufactured by Freund Turbo Co., Ltd.), Centricutter (manufactured by Nippon Coke Industry Co., Ltd.), Rotary Cutter Mill (manufactured by Nara Kikai Seisakusho Co., Ltd.), Turbo Cutter (manufactured by Freund Turbo Co., Ltd.), and Pulp Crusher (manufactured by Zuiko Co., Ltd.). It will be done.

Examples of the hammer type mill include a hammer mill (manufactured by Hosokawa Micron Co., Ltd.), a jaw crusher (manufactured by Makino Co., Ltd.), and a hammer crusher (manufactured by Makino Sangyo Co., Ltd.).

Examples of impact mills include Pulverizer (manufactured by Hosokawa Micron Corporation), Fine Impact Mill (manufactured by Hosokawa Micron Corporation), Super Micron Mill (registered trademark, manufactured by Hosokawa Micron Corporation), Innomizer (registered trademark, manufactured by Hosokawa Micron Corporation), Fine Mill (manufactured by Japan Pneumatic Industries Co., Ltd.), CUM centrifugal mill (manufactured by Mitsui Mining Co., Ltd.), Exceed Mill (manufactured by Makino Sangyo Co., Ltd.), Ultraplex (manufactured by Makino Sangyo Co., Ltd.), Contraplex (manufactured by Makino Sangyo Co., Ltd.) Coloplex (manufactured by Makino Sangyo Co., Ltd.), Atomizer (manufactured by Seishin Kogyo Co., Ltd.), Tornado Mill (manufactured by Nikkiso Co., Ltd.), Nair Mill (manufactured by Dalton Co., Ltd.), Jiyu Grinder (manufactured by Nara Kikai Seisakusho Co., Ltd.) ), New Cosmomizer (manufactured by Nara Kikai Seisakusho Co., Ltd.), Turbo Mill (manufactured by Freund Turbo Co., Ltd.), Super Powder Mill (manufactured by Nishimura Kikai Seisakusho Co., Ltd.), Blade Mill (manufactured by Nisshin Engineering Co., Ltd.), Super Rotor (manufactured by Nisshin Engineering Co., Ltd.) (manufactured by Nisshin Engineering Co., Ltd.), Willey crusher (manufactured by Sanki Seisakusho Co., Ltd.), pulp crusher (manufactured by Zuiko Co., Ltd.), Jacobson fine grinder (manufactured by Shinko Pantech Co., Ltd.), Universal mill (manufactured by Tokuju Kosho Co., Ltd.) (manufactured by Eurus Techno Co., Ltd.) and continuous vibromill (manufactured by Eurus Techno Co., Ltd.).

Examples of airflow mills include CGS type jet mill (manufactured by Mitsui Mining Co., Ltd.), Micron Jet (registered trademark, manufactured by Hosokawa Micron Co., Ltd.), Counter Jet Mill (registered trademark, manufactured by Hosokawa Micron Co., Ltd.), and Cross Jet Mill (trademark manufactured by Hosokawa Micron Co., Ltd.). Kurimoto Iron Works Co., Ltd.), supersonic jet mill (Japan Pneumatic Industry Co., Ltd.), current jet (Nissin Engineering Co., Ltd.), jet mill (Sansho Industry Co., Ltd.), selenium mirror (Masuko Sangyo Co., Ltd.) company), New Microsictomat (manufactured by Masuno Seisakusho Co., Ltd.), Kryptron (manufactured by Earth Technica Co., Ltd.), and Nano Jet Miser (manufactured by Aisin Nano Technologies Co., Ltd.).

Examples of the roller mill include a vertical roller mill (manufactured by Seishin Co., Ltd.), a vertical roller mill (manufactured by Shinion Co., Ltd.), a roller mill (manufactured by Kotobuki Giken Kogyo Co., Ltd.), and a VX mill (manufactured by Kurimoto Iron Works Co., Ltd.). ), KVM type vertical roller mill (manufactured by Earth Technica Co., Ltd.), and IS mill (manufactured by IHI Plant Engineering Co., Ltd.).
Examples of the vibration mill include a batch type vibration mill (manufactured by Chuo Kakoki Co., Ltd.).
Among these, cutting type mills, roller mills, and vibration mills are preferred.

The conditions for the pulverization treatment can be appropriately set so as to obtain the desired powdered cellulose. For example, the processing conditions can be adjusted with reference to a calibration curve created from the pulverization conditions (eg, processing time, input amount) and desired physical properties of the powdered cellulose.

[Neutralization, cleaning, dehydration, drying treatment]
When producing powdered cellulose from cellulose raw materials, appropriate pretreatment is performed before pulverization. Examples of pretreatment include neutralization, washing, deliquification, and drying treatment, and it is preferable to perform dehydration and drying treatment in this order. The solid content concentration of the cellulose raw material can be adjusted by drying (dehydration) treatment, and the physical properties of the powdered cellulose can be easily controlled. The solid content concentration is usually adjusted to 15% or more, preferably 20% or more. For drying, it is preferable to use a flash dryer. As a result, regardless of whether the processed cellulose raw material is in the form of a cake-like solid, slurry, solution, etc., it is possible to apply high-speed hot air while dispersing it in the air stream, and also to utilize the depressurizing effect inside the dryer. , can be dried instantly. In addition, since the exposure time to hot air is extremely short, the product temperature can be kept low, making it ideal for drying products that are sensitive to heat or products with low melting points. The conditions for drying using the flash dryer are not particularly limited and can be set as appropriate, but an example is as follows. The outlet drying temperature is usually 80 to 180°C, preferably 90 to 160°C. The amount of air supplied is usually 150 to 350 m ³ /h, preferably 160 to 320 m ³ /h.
On the other hand, when using a spray dryer, the product is sprayed and instantly dried with hot air to produce granules. Therefore, it may not be suitable for drying solid or semi-solid objects with a small moisture content. Furthermore, the particles are more easily exposed to high heat instantaneously than when drying with a flash dryer, and there may be concerns about the effect on the product.

[Acid hydrolysis treatment]
Examples of acids used in the acid hydrolysis treatment include mineral acids such as hydrochloric acid, sulfuric acid, and nitric acid. The acid concentration is not particularly limited, but from the viewpoint of maintaining the degree of polymerization and whiteness, it is preferably lower than the acid concentration in the conventional acid hydrolysis treatment for producing powdered cellulose, and is preferably 0.4 to 2.0N. More preferably, 0.5 to 1.5N is more preferable. When the acid concentration is less than 0.4N, depolymerization of cellulose due to acid is suppressed and a decrease in the degree of polymerization of cellulose can be reduced, but it may be difficult to refine the cellulose. On the other hand, if it exceeds 2.0N, the depolymerization of cellulose progresses and it becomes easier to refine the powder, improving powder flowability, but tablet hardness decreases as the degree of polymerization decreases (when molded, it disintegrates). It may be easier to do so.) The reaction conditions for the acid hydrolysis treatment are not particularly limited, but the reaction temperature is usually 80 to 100°C and the reaction time is usually 30 minutes to 3 hours.

Prior to the acid hydrolysis treatment, the cellulose raw material may be pretreated. Examples include slurrying the cellulose raw material (preparation of a dispersion) and adjusting the concentration of the cellulose raw material. The concentration of the cellulose raw material is usually 3 to 10% by weight (based on solid content) based on the dispersion. When the cellulose raw material is a fluidized pulp that has undergone bleaching treatment, a treatment to increase the pulp density is usually performed before hydrolysis. A dehydrator such as a screw press or a belt filter may be used to adjust (concentrate) the cellulose raw material concentration. The acid hydrolysis treatment may be performed on a slurry of cellulose raw material, or may be performed on a sheet-shaped cellulose raw material. When the cellulose raw material is a dry sheet of pulp, the acid hydrolysis treatment is usually performed after the pulp is loosened. When loosening the pulp, a crusher such as a roll crusher may be used.

During the pulverization treatment after acid hydrolysis, at least one other component (for example, an organic component, an inorganic component) may be subjected to the pulverization treatment together with the acid-hydrolyzed product, if necessary. Thereby, functionality can be imparted to the powdered cellulose or the functionality can be improved. The amounts of other components to be blended may be appropriately selected. Further, prior to the pulverization step, the acid-hydrolyzed product may be further subjected to the above-mentioned neutralization, washing, dehydration, and drying treatments.

The cellulose material may be chemically treated as necessary. The chemical treatment is preferably a treatment that does not significantly impair the degree of polymerization of the cellulose raw material. The chemical treatment may be performed on the cellulose raw material during the pulverization treatment, or may be performed before the pretreatment of the pulverization treatment.

[2.3. Method for producing fibrous cellulose]
Fibrous cellulose can be produced by a method including defibration treatment. Defibration (fibrillation) is usually obtained by mechanical treatment, and the mechanical treatment is preferably defibration or beating treatment. The mechanical treatment (preferably beating or disintegration treatment) is usually carried out wet (ie in the form of an aqueous dispersion). Examples of devices used for mechanical processing include refining devices (refiners; e.g., disk type, conical type, cylinder type), high-speed fibrillators, shear type stirrers, colloid mills, high-pressure injection dispersers, beaters, PFI mills, Kneader, disperser, high-speed disintegrator (top finer), high-pressure or ultra-high-pressure homogenizer, grinder (stone mill type crusher), ball mill, vibration mill, bead mill, single-shaft, double-shaft or multi-shaft kneading machine or high-speed extruder homomixers under rotation, refiners, defibrators, friction grinders, high-share defibrators, dispergers, homogenizers (e.g., microfluidizers) A device that can apply a mechanical defibrating force such as a microfluidizer (microfluidizer) can be mentioned, and a device that can apply a defibrating force in a wet manner is preferable, and a high-speed disintegrator and a purification device are more preferable, but there are no particular limitations. Defibration treatment is usually performed with the cellulose raw material dispersed in water.

If the fibrous cellulose is modified fibrous cellulose, chemical modification treatment is performed before or after (usually before) defibration. Examples of the modification treatment include oxidation, etherification, esterification such as phosphoric acid esterification, silane coupling, fluorination, and cationization. Among these, oxidation (carboxylation), etherification (for example, carboxyalkylation), cationization, and esterification are preferred, and oxidation (carboxylation) and carboxyalkylation are more preferred.

[3. Uses of cellulose materials]
Applications of cellulose materials include, for example, industrial additives (for example, for resins such as polypropylene, phenol resin, melamine resin, and various rubbers), and for tablets and other preparations (foods, pharmaceuticals, quasi-drugs, cosmetics). It can be used as an excipient. In addition, resin compositions (e.g., polyolefin resins, modified polyolefin resins, rubber), rubber compositions (e.g., automobiles, personal computers, building materials, containers), food additives (e.g., shredded cheese, fried products, bread crumbs, ham, sausage casings, their pickle liquid), hygiene products/cosmetics (e.g. for face washes, toothpastes, foundations), filter aids (e.g. rare metals, food grade), paint/adhesive additives (e.g. urethane paints) It can be used as an ingredient or raw material for feed (e.g., pet food, fishing bait), etc.

[4. Molded body]
Powdered cellulose can be used as an excipient for molded bodies (for example, preparations for foods, medicines, quasi-drugs, cosmetics, manufacturing industry, construction industry, etc.). Thereby, the molded product can exhibit good hardness. Examples of the dosage form of the molded product include tablets.

It is preferable that the molded body has a moderate (practical) hardness, for example, usually 30 MPa or more, more preferably 40 MPa or more, still more preferably 50 MPa or more. The upper limit is preferably 100 MPa or less, more preferably 80 MPa or less, still more preferably 60 MPa or less. Therefore, the hardness of the powdered cellulose is preferably 30 to 100 MPa, more preferably 40 to 80 MPa, and still more preferably 50 to 60 MPa. Tablet hardness can be measured, for example, using a tablet hardness meter under the conditions shown in Examples.

Hereinafter, the present invention will be explained with reference to Examples. The following examples do not limit the invention. The test method in the Examples of the present application is shown below. Note that the measurement methods for physical property values, etc. are the measurement methods described above, unless otherwise specified.

<Measurement of iron component content (ppm)>
A sample was prepared by weighing 0.5 g of powdered cellulose into a microwave digestion container and adding 2 ml of pure water and 5 ml of nitric acid. After the sample was subjected to microwave digestion, it was transferred to a constant volume polypropylene container. After adding 2 ml of the internal standard solution to the sample, the volume was fixed (50 ml), and the iron component content was measured using a triple quadrupole ICP mass spectrometer.

The measurement conditions of the ICP mass spectrometer are as follows.
・Model: Agilent 8800 (manufactured by Agilent Technologies Co., Ltd.)
・Collision and reaction cell introduction gas: Helium and hydrogen ・Measurement m/z: Iron; 56
・Internal standard element m/z: Rhodium; 103

<Ash content (%)>
The ash content was measured using the following procedure.
1) 5 to 8 g of the sample was placed in a porcelain crucible of known weight, and the sample weight was accurately weighed. The crucible was air-baked in advance (800° C., about 1 hour) before the sample was placed in it, and the weight was accurately weighed after cooling in a desiccator for 30 minutes. If soda ash was melted and accumulated in the crucible, it was washed with hydrochloric acid.
2) After accurate weighing, the crucible containing the sample was heated with an electric heater to carbonize it. Carbonization was carried out until no white smoke was produced. Thereafter, it was placed in an electric furnace adjusted to 800°C and incinerated for 2 hours.
3) After incineration, the crucible was taken out and placed in a desiccator.
4) After cooling for 30 minutes, the incinerated residue was accurately weighed using a precision balance. The ash content was calculated using the following formula, calculated to three decimal places, and reported to two decimal places.

ATX224 (Shimadzu Corporation) was used as the precision balance, and FUW232PA (ADVANTEC) was used as the electric furnace.

<Particle size distribution, average particle size, span of particle size distribution>
A laser diffraction particle size distribution analyzer (Mastersizer 3000, Spectris Malvern Panalytical Division) was used. Using a laser scattering method as the measurement principle, particle size distribution was measured by dry measurement, wet measurement (with ultrasonic irradiation), and wet measurement (without ultrasonic irradiation). When the particle size distribution is expressed as a volume accumulation distribution, the values at which the integrated value of the volume accumulation distribution is 10%, 50%, and 90% are respectively defined as the particle size distribution D. 10,D. 50, D. It was set at 90. Wet type (no ultrasonic irradiation) D. 50 was taken as the average particle diameter. Furthermore, the span of the particle size distribution was calculated using the above equation (1).

The dry measurement was carried out under the following conditions by adding a sample into the supply port so that the scattering intensity was less than 1%.
・Distributed unit: Aero5
・Air pressure: 2 bar
・Feed rate: 25

Wet measurements were carried out by adding a sample to a measuring section in water that was stirred at 3500 rpm so that the scattering intensity was about 10%. When applying ultrasonic waves, wet measurements were performed after applying ultrasonic waves to the sample in water based on the following conditions.
・Mode: Continuous ・Intensity: 100%
・Time: 600 seconds

The analysis of particle size distribution was carried out under the following conditions for all measurement conditions.
・Analysis: General purpose ・Analysis sensitivity: Enhancement ・Light scattering model: Mie theory

<Average fiber length (mm), average fiber width (μm), L/D>
Measurement was performed using L&W Fiber Tester Plus (manufactured by ABB) according to the following procedure. 0.1 g of the sample was placed in a cylinder containing 200 ml of pure water, stirred for about 1 minute, then transferred to a special 300 ml beaker, set in a sample cycler, and started measurement to measure the average fiber length and average fiber width. . L/D was calculated from the obtained average fiber length and average fiber width.

<Thermogravimetric residual rate (500°C)% or thermogravimetric residual rate (400°C)%>
The thermogravimetric residual rate was measured using a thermal analyzer. That is, heat the powdered cellulose to 600°C (in an oxygen-free, nitrogen atmosphere), read the weight at 500°C or 400°C, and calculate the ratio (%) to the weight before the start of heating as the thermogravimetric residual rate (500°C). It was calculated as % (°C)% or thermogravimetric residual rate (400°C)%.

<Tablet hardness (10MPa)>
A cylindrical molded body or tablet made of 100% cellulose powder was produced as follows. 0.3 g of the sample was placed in a mortar (manufactured by Ichihashi Seiki Co., Ltd., 8 mm in diameter) and compressed with a pestle (manufactured by Ichihashi Seiki Co., Ltd.) with a diameter of 8 mm. 100% cellulose powder was compressed at 10 MPa and the stress was maintained for 10 seconds to produce a cylindrical molded body or tablet (the compressor used was HANDTAB-100 manufactured by Enerpac).

The load when the produced cylindrical molded body or tablet was broken was measured using a Schleungel hardness meter (manufactured by Freund Sangyo Co., Ltd., model MT50). The load was applied in the diametrical direction of the cylindrical molded body or tablet. Calculated using the average value of 5 samples.

<Preparation of powdered cellulose>
(Example 1)
A pulverized product obtained by cutting a bleached wood pulp sheet (LBKP dry sheet, manufactured by Nippon Paper Industries Co., Ltd., moisture 20%) with a cutting mill (PIH3-20210YRFS, manufactured by Horai Co., Ltd., using a 3 mm diameter punching plate) as a raw material. was pulverized with a vertical roller mill (STR-20, manufactured by Seishin Enterprise Co., Ltd., feed rate 600 g/min, pulverizing rotor 40 Hz, classification rotor 50 Hz, blower 50 Hz), and the obtained pulverized product was used as the powdered cellulose of Example 1. It was used as Various physical property values are shown in Table 1.

(Example 2)
The process was carried out in the same manner as in Example 1, except that a cutting mill (HA8-2542, manufactured by Horai Co., Ltd., main mesh #250, auxiliary mesh #20) was used as the second-stage crusher, and the obtained pulverized product was It was used as the powdered cellulose in Example 2. Various physical property values are shown in Table 1.

(Example 3)
Wood pulp (thermomechanical pulp, manufactured by Nippon Paper Industries Co., Ltd., moisture 60%) is dehydrated, loosened and dried, and then processed into a cutting mill (HA8-2542, manufactured by Horai Co., Ltd., main mesh #). 250, auxiliary mesh #50), and the resulting pulverized product was used as powdered cellulose in Example 3. Various physical property values are listed in Table 1.

(Example 4)
Using a bleached wood pulp sheet (NDPT dry sheet, manufactured by Nippon Paper Industries Co., Ltd., moisture 7%) as a raw material, a raw material charge amount of 100 kg and a feed rate of 5. It was pulverized under the conditions of 0 kg/min and 10 rpm. The obtained pulverized product was processed using a batch type vibration mill (MB3 type, manufactured by Chuo Kakoki Co., Ltd.) with a raw material charge amount of 45 g (0.25 L), a vibration frequency of 1000 cpm, an amplitude of 8 mm, a ball diameter of 30 mm, and a ball filling rate of 80. % for 30 minutes, and the resulting pulverized product was used as the powdered cellulose of Example 4. Various physical property values are listed in Table 1.

(Example 5)
The same operation as in Example 4 was carried out, except that a bleached wood pulp sheet (LDPT dry sheet, manufactured by Nippon Paper Industries, Ltd., water content: 7%) was used, and the obtained pulverized material was mixed with the powdered cellulose of Example 5. It was used as Various physical property values are shown in Table 1.

(Example 6)
A bleached wood pulp sheet (NDPT dry sheet, manufactured by Nippon Paper Industries Co., Ltd., moisture 7%) was used as a raw material, and a raw material amount of 40 g (pulp slurry concentration 5%) was acid-hydrolyzed with 0.5N hydrochloric acid at 90°C for 40 minutes. The obtained powdered cellulose was used as the powdered cellulose of Example 6. Various physical property values are listed in Table 1.

(Comparative example 1)
Commercially available powdered cellulose ST-02 (manufactured by Asahi Kasei Corporation) was used as the powdered cellulose in Comparative Example 1. Various physical property values are listed in Table 1.

Compared to Comparative Example 1, which does not contain an iron component, Examples 1 to 6 containing an iron component had higher thermogravimetric residual rates, and among them, Examples 1 to 3 were higher. Furthermore, the thermogravimetric residual rates of Examples 1 to 6 were proportional to the ash content. These results show that the powdered cellulose of the present invention has a high yield after heat treatment and is excellent in recyclability because it contains an iron component.

On the other hand, in Example 3, it was difficult to make tablets, whereas in Examples 4 to 6, it was possible to make tablets. The tablets obtained from Examples 4 to 6 had appropriate hardness. It is presumed that in Comparative Example 1, as a result of no inorganic substance being contained, the frictional force on the tablet surface was strong, making it easier to break, whereas in Example 3, the tablet was not formed as a result of the high inorganic substance content. These results show that the powdered cellulose of the present invention has a high yield after heat treatment, excellent recyclability, and excellent suitability for tabletting because it contains a relatively small amount of iron component.

Claims (17)

1. A cellulose material in which the amount of iron component detected by a triple quadrupole-inductively coupled plasma mass spectrometer is 1 to 50 ppm.
2. The cellulose material according to claim 1, wherein the amount of iron component detected by a triple quadrupole-inductively coupled plasma mass spectrometer is more than 10 ppm and less than 50 ppm.
3. The cellulose material according to claim 1 or 2, wherein the ash content after heating at 800°C for 2 hours is 0.13% by weight or more based on 100% by weight of the cellulose material before heating.
4. The cellulose material according to any one of claims 1 to 3, which has a thermogravimetric residual rate at 500°C of 10% or more.
5. The cellulose material according to any one of claims 1 to 4, having an average fiber width of 10 to 24 μm.
6. The cellulose material according to claim 1, wherein the amount of iron component detected by a triple quadrupole-inductively coupled plasma mass spectrometer is 1 to 10 ppm.
7. The cellulose material according to claim 6, wherein the ash content after heating at 800°C for 2 hours is 1.0% by weight or less based on 100% by weight of the cellulose material before heating.
8. The cellulose material according to any one of claims 1 to 7, which has a thermogravimetric residual rate at 400°C of 10 to 20%.
9. The cellulose material according to any one of claims 1 to 8, wherein the average fiber length/average fiber width is 3.0 to 8.0.
10. The cellulose material according to any one of claims 1 to 9, which is powdered cellulose.
11. The cellulose material according to claim 10, having an average particle diameter of 5.0 to 150.0 μm.
12. An industrial additive comprising the cellulose material according to any one of claims 1 to 11.
13. A resin composition comprising the cellulose material according to any one of claims 1 to 10.
14. A rubber composition comprising the cellulose material according to any one of claims 1 to 11.
15. An excipient comprising the cellulose material according to any one of claims 1 to 11.
16. A molded article comprising the cellulose material according to any one of claims 1 to 11.
17. The molded article according to claim 16, which has a hardness of 30 to 100 MPa.