WO2018207945A1 - Cnf molding device and cnf molding method - Google Patents

Abstract

[Problem] To provide a CNF molding device with which a CNF molded body having a 3-dimensional shape can be obtained. [Solution] In a state in which a mold cavity 4 is formed by a bottom plate 3 and a body portion 2, cellulose nanofiber (CNF) is loaded into the mold cavity 4 from a nozzle 6 mounted to an upper plate 2b. At around the same time, heating of a mold portion 2a is started. In a state in which a certain amount or more of CNF has been accumulated in the mold cavity 4, the upper plate 2b is pressurized in the direction of the bottom plate 3, whereby the entire body portion 2 being supported in a movable state moves in the direction of the bottom plate 3, the bottom plate 3 is fitted into the mold portion 2a, and the volume of the mold cavity 4 decreases. In the process, the CNF in the heated mold portion 2a contracts while externally discharging vapor via the upper plate 2b, which comprises a porous body, and is molded into a predetermined shape due to the shape of the mold cavity 4, producing a required molded body 9.

Description

CNF molding apparatus and CNF molding method

The present invention relates to a CNF molding method.

Cellulose is a natural and fibrous form of plants, for example, woody plants such as broad-leaved trees and conifers, and herbaceous plants such as bamboo and bamboo, some animals represented by sea squirts, and some represented by acetic acid bacteria. It is known that it is produced by fungi and the like. A cellulose fiber having a structure in which cellulose molecules are aggregated in a fibrous form is called a cellulose fiber. In particular, a cellulose fiber having a fiber width of 100 nm or less and an aspect ratio of 100 or more is generally called cellulose nanofiber (CNF), and has excellent properties such as light weight, high strength, and low thermal expansion coefficient.

Naturally, CNF does not exist as a single fiber except for CNF produced by some fungi represented by acetic acid bacteria. Most of CNF exists in the state which has the fiber width of the micro size tightly assembled by the interaction represented by the hydrogen bond between CNF. The fibers having the micro-sized fiber width also exist as higher order aggregates.

In the papermaking process, the fiber aggregate wood is defibrated to a pulp state with a micro-sized fiber width by a pulping method represented by kraft cooking, which is one of chemical pulping methods. The paper is made from this. The fiber width of this pulp varies depending on the raw material, but it is 5-30 μm for bleached kraft pulp made from hardwood, 20-100 μm for bleached kraft pulp made from softwood, and 5-30 μm for bleached kraft pulp made from bamboo. Degree.

As described above, the pulp having these micro-sized fiber widths is an aggregate of single fibers having a fibrous form in which CNF is firmly assembled by an interaction typified by hydrogen bonding, and by further defibrating. CNF having nano-sized fiber width can be obtained.

Many methods for preparing CNF have been reported, but they are roughly classified into two types: chemical methods such as acid hydrolysis and TEMPO catalytic oxidation, and physical methods such as grinder method, high-pressure homogenizer method, and underwater facing collision method. . Whichever method is used, CNF is basically obtained in a state of being dispersed in water.

The following patent documents are disclosed in the molding method for slurry containing CNF and the method for producing a molded body.

Patent Document 1 discloses a step of bringing a liquid containing one or two or more solvents and one or two or more polymers into contact with the surface of a porous substrate, and removing the solvent by the porous substrate to obtain a solid content concentration of the liquid. As a polymer used to form a molded product by a step of forming a molded product with a content of 4% or more, there is a fibrous polymer having a minor axis direction of 1 nm to 500 nm and a major axis direction of 500 nm to 1000 μm. A method for producing a molded product was disclosed.

Patent Document 2 discloses a cellulose nanofiber having an average fiber diameter of 10 to 100 nm and an average aspect ratio of 1000 or more for solving the problem of providing a high-strength and light-weight material that does not generate combustion residues upon disposal. High-strength material having a density of 1.2 g / cm 3 or more and 1.4 g / cm 3 or less, a bending strength of 200 MPa or more, and a bending elastic modulus of 14 GPa or more by pressing the fiber at a high temperature and a high pressure. Disclosed.

JP2011-038031 JP2013-11026A

However, since the CNF molded body obtained by the CNF molding method disclosed in these patent documents is about 2 mm at most, for example, it cannot be desired to obtain some shaped article by cutting the molded body. As described above, CNF is dispersed in water, and the CNF content in the dispersion is about 0.1 to 10%. When trying to obtain a uniform CNF compact, the amount of solvent in the CNF dispersion inevitably increases. Therefore, the time for removing the solvent from the CNF dispersion increases. If much time is required, even if a CNF molded body can be produced, a CNF layer or cavity is generated inside the molded body, and a uniform molded body cannot be obtained.

In view of the problems in the prior art described above, the present invention reduces the time required for solvent removal, and has a thickness that enables cutting, and can obtain a molded body having a uniform inside. It aims at providing a shaping | molding apparatus and a CNF shaping | molding method.

A first aspect of the present invention is a CNF molding apparatus in which a load is applied using a vapor permeation means for allowing vapor to permeate through a slurry containing cellulose nanofiber (hereinafter referred to as CNF), and a molding cavity is formed by a main body portion and a bottom plate. A molding die to be formed, CNF feeding means for the molding cavity is provided, the bottom plate is fitted inside the main body, and has pressurizing means for pressurizing the main body toward the bottom plate. It is a feature.

According to a second aspect of the present invention, there is provided a CNF molding method in which a load is applied using a vapor permeation means that allows vapor to permeate the CNF-containing slurry. CNF insertion means for the cavity is provided, and the bottom plate can be fitted inside the main body, and has a step of pressurizing the main body in the direction of the bottom plate.

According to the present invention, it is possible to obtain a CNF molded body that has a thickness that enables a cutting process and a uniform inside while reducing the time required for solvent removal.

It is a conceptual diagram of the CNF shaping | molding apparatus of one embodiment of this invention. It is a photograph of the molded object obtained by the CNF shaping | molding apparatus of one embodiment of this invention. 3 is a photograph of a product obtained by cutting out from the molded body shown in FIG. 2. It is another photograph of the product obtained by shaving from the molded body shown in FIG. The bending strength data shown in Table 6 are illustrated. The data of the bending elastic modulus shown in Table 8 is illustrated. The contact angle data shown in Table 9 are illustrated.

As shown in FIG. 1, the CNF molding apparatus 1 of the present embodiment includes a main body 2 and a bottom plate 3 that are supported in a movable state and use vapor transmission means. The bottom plate 3 is held in a non-movable state. A molding cavity 4 is formed by the main body 2 and the bottom plate 3. Furthermore, the main body 2 is composed of a mold part 2a, a mold part 2a using a vapor transmission means, and an upper plate 2b, and the upper plate 2b is disposed on the opposite side of the bottom plate 3 through the mold part 2a. The The upper plate 2b is equipped with a hydraulic actuator 5 which is a pressurizing means, and by applying a load to the hydraulic actuator 5, the mold part 2a can be pressed in the direction of the bottom plate 3 by the upper die 2b. Further, the upper die 2b is provided with a nozzle 6 as means for feeding CNF into the molding cavity 4.

In the vicinity of the mold part 2a, a far infrared ray generator 7 as a heating means for heating the mold part 2a is arranged. Moreover, a belt heater etc. can be used as another heating means.
In the CNF molding apparatus 1 of the present embodiment as described above, the inner diameter of the mold part 2a and the outer diameter of the bottom plate 3 are made to substantially coincide with each other so that the bottom plate 3 can be fitted inside the mold part 2a. .
On the other hand, as a result of the outer diameter of the upper mold 2b and the outer diameter of the mold part 2a being substantially matched, when the upper plate 2b is pressed in the direction of the bottom plate 3 by the hydraulic actuator 5, the applied pressure is The entire main body 2 that is transmitted to the portion 2a and supported in a movable state moves in the direction of the bottom plate 3.
On the other hand, as a result of the bottom plate 3 held in a non-movable state being held at a fixed position, when the entire main body portion 2 moves in the direction of the bottom plate 3, the bottom plate 3 is fitted inside the mold portion 2a, and the volume of the molding cavity 4 decreases. To do.

As the vapor transmission means, for example, a porous body using a porous material can be used. As the porous material, various materials such as organic, inorganic, metal, or composites thereof, specifically stainless steel, SiC, ceramic, resin, rubber, glass, paper, etc. can be used. . These may be used in combination as necessary. Further, the average pore diameter and porosity of the porous body to be used can be those having an average pore diameter of 5 to 200 μm and a porosity of 30 to 85%, preferably an average pore diameter of 5 to 60 μm and a porosity. It is recommended to use 40 to 70%.
The porosity is (1) the sum of the volume of pores communicating with the outside and the volume of pores enclosed inside divided by the total volume (apparent volume), and (2) leading to the outside. There are two types: the pore volume divided by the total volume. In the present invention, any one of the calculation methods can be used.

As a method of improving permeation, a method of concentrating using an object that allows vapor to permeate can be considered. Vapor-permeable objects include fabrics, felts, various filters such as membrane filters and sintered filters, filter paper, materials with a permeation mechanism such as holes, stacked plates and rods, porous and fine substances. Aggregates (pseudo porous structure formed of fine substances such as sand and silica) are also possible. Further, when a hydrophilic base material is used, water can be easily dehydrated. Furthermore, if the transmission mechanism is 1 μm or less, CNF can be prevented from flowing out. Furthermore, these can be used alone or in combination. Moreover, there is no restriction | limiting about the direction which permeate | transmits a load and vapor | steam. Moreover, it is possible to permeate | transmit a vapor | steam under vacuum conditions and pressure reduction conditions, and the means in particular is not restrict | limited.

By providing the nozzle 6 which is a CNF charging unit for the inside of the molding cavity 4, the volume of the obtained molded body can be adjusted. Without this nozzle, the size of the molded body obtained is extremely small compared to the size of the molding cavity of the mold part, but by adding CNF-containing slurry from the nozzle The mold shape can be maintained.

The CNF molding process performed using the CNF molding apparatus 1 of the above embodiment will be described.
First, the CNF-containing slurry is introduced into the molding cavity 4 from the nozzle 6 mounted on the upper plate 2 b in a state where the molding cavity 4 is formed by the bottom plate 3 and the main body 2. Around this time, heating of the mold part 2a by the far infrared ray generator 7 is started.
When the upper plate 2b is pressurized in the direction of the bottom plate 3 by the hydraulic actuator 5 in a state where a certain amount or more of CNF is stored in the molding cavity 4, the entire main body 2 supported in a movable state moves in the direction of the bottom plate 3, 3 fits inside the mold part 2a, and the volume of the molding cavity 4 decreases. In the process, the heated CNF inside the mold part 2 a is reduced while discharging steam to the outside through the upper plate 2 b made of a porous body, and is predetermined according to the shape of the molding cavity 4. The required molded body 8 can be obtained by molding into a shape. In this case, the CNF compact 8 having a required volume can be obtained by replenishing CNF from the nozzle 6 in the molding process.
In the above case, if the top plate 2b and the bottom plate 3 are also preheated by the far infrared ray generator 7, the time can be shortened.

[CNF-containing slurry]
In the present invention, examples of CNF include polysaccharide-derived CNF including natural plants such as wood fiber, bamboo fiber, sugarcane fiber, seed hair fiber, and leaf fiber. These CNFs may be used alone or in combination of two or more. May be used in combination.
The CNF used in the present invention has an average thickness of 3 to 200 nm and an average length of 0.1 μm or more. For example, the CNF can be prepared by defibrating a polysaccharide with a high-pressure water stream. The defibration of the polysaccharide with a high-pressure water stream is carried out by colliding high-pressure water of about 50 to 400 MPa with the polysaccharide in a 0.5 to 10% by mass water mixture. For measurement of average thickness and average fiber length, select a scanning electron microscope (SEM), a transmission electron microscope (TEM), etc., observe and measure CNF, and select 20 or more from the obtained photographs. This is obtained by averaging each. However, the preparation method of CNF used in the present invention is not limited to this, and can also be prepared by a chemical method such as an acid hydrolysis method or a TEMPO catalytic oxidation method, or a physical method such as a grinder method or a high-pressure homogenizer method. .

In the present invention, a CNF-containing slurry is prepared by adding a metal salt, a hardwood, a conifer or a pulp made from bamboo or a cross-linking agent to a CNF aqueous dispersion. Furthermore, what replaced the water solvent with the organic solvent can also be used as a CNF containing slurry.

On the other hand, CNF generally has a large number of hydroxyl groups in its molecule and is known to be extremely hydrophilic. Therefore, when a CNF molded body is produced with a number of hydroxyl groups in the molecule, the hydrophilicity and water absorption of the CNF molded body itself can be a problem. That is, it may be required that the CNF molded body can be used even in a situation where water resistance is required.

Therefore, in order to solve this problem, it is possible to use a hydrophobic CNF in which a part of the functional group is modified to vinyl esters or organic acid vinyl esters. These vinyl esters or organic acid vinyl esters include linear or branched C2 such as vinyl acetate, vinyl butyrate, vinyl stearate, vinyl laurate, vinyl myristate, vinyl propionate, vinyl versatate, etc. -20 aromatic carboxylic acids such as vinyl esters of aliphatic carboxylic acids and vinyl benzoates. When such hydrophobic CNF is used, a hydrophobic CNF molded product can be prepared.

Next, the CNF concentration in the CNF-containing slurry is preferably in the range of 2% to 10%. If it is 2% or less, the amount of solvent is large, and it takes time to dehydrate. Further, if it is 10% or more, the inside of the CNF compact is hollow. Further, the temperature range of the CNF-containing slurry is adjusted to 20 to 95 ° C., preferably 40 to 80 ° C., using the heating means. When the liquid temperature is 20 ° C. or lower, dehydration takes time. Moreover, when it becomes more than the boiling point of a solvent, it will be in a boiling state, a bubble trace will generate | occur | produce in a molded object, and a uniform molded object cannot be obtained.

[Metal salt]
The metal salt added to the CNF aqueous dispersion is preferably, for example, one or more compounds selected from the group consisting of inorganic phosphorus compounds, phosphorous acid or hypophosphorous acid metal salts. If a light aggregate of CNFs is formed by adding a metal salt, the time for dehydrating the solvent can be reduced.
Examples of inorganic phosphorus compounds include phosphoric acid compounds, phosphorous acid compounds, and hypophosphorous acid compounds. Specific examples of such phosphoric acid compounds include phosphoric acid, diphosphoric acid, triphosphoric acid, lithium phosphate, beryllium phosphate, sodium phosphate, magnesium phosphate, aluminum phosphate, potassium phosphate, calcium phosphate and the like. Specific examples of phosphite compounds include phosphorous acid, lithium phosphite, beryllium phosphite, sodium phosphite, magnesium phosphite, aluminum phosphite, potassium phosphite, calcium phosphite and the like. Specific examples of the hypophosphite compound include hypophosphorous acid, lithium hypophosphite, beryllium hypophosphite, sodium hypophosphite, magnesium hypophosphite, aluminum hypophosphite, Examples thereof include potassium phosphite and calcium hypophosphite.
Besides, for example, hydroxides such as potassium hydroxide, sodium hydroxide, barium hydroxide, lithium hydroxide; zinc chloride, aluminum chloride, calcium chloride, strontium chloride, ferric chloride, ferric chloride , Chlorides such as cupric chloride, barium chloride, manganese chloride, manganese chloride, manganese chloride, sodium chloride, potassium chloride; zinc chloride, aluminum sulfate, potassium sulfate, zirconium sulfate, copper sulfate, sulfuric acid Sulfates such as sodium, magnesium sulfate, manganese sulfate; nitrates such as zinc nitrate, aluminum nitrate, potassium nitrate, calcium nitrate, strontium nitrate, copper nitrate, sodium nitrate, barium nitrate, magnesium nitrate, manganese nitrate; zinc acetate, potassium acetate, Calcium acetate, strontium acetate, sodium acetate Barium acetate, acetates such as magnesium acetate, and the like.
Among these compounds, a divalent metal ion such as magnesium or calcium or a trivalent metal ion such as aluminum is more preferable.
Further, the amount to be added is 1% or more, more preferably 5% to 10%, relative to the obtained CNF molded product. If it is added in an amount of 10% or more, the strength of the CNF compact may be lowered.

[pulp]
The pulp added to the CNF aqueous dispersion may be any of pulp made from hardwood, pulp made from softwood, pulp made from bamboo, or a combination thereof. A pulp fiber length of 0.5 to 5.0 mm and a pulp fiber length of 10 to 100 μm may be appropriately selected and used. Furthermore, the addition amount is preferably in the range of 10 to 30% with respect to the obtained CNF molded product. At this time, when the amount of pulp added is 10% or less, the time required for filtration is not shortened. When 30% or more is added, even if more is added, the filtration time is reduced. This is because it does not have much influence on shortening.

[Crosslinking agent]
As a crosslinking agent, it has reactivity with a functional group modified by a hydroxyl group possessed by cellulose nanofiber or modified cellulose nanofiber, a hydroxyl group having another functional group such as a carboxyl group, a phosphate group, or an amino group. For example, an isocyanate crosslinking agent, an epoxy crosslinking agent, an amine crosslinking agent, a melamine crosslinking agent, an aziridine crosslinking agent, a hydrazine crosslinking agent, an aldehyde crosslinking agent, an oxazoline crosslinking agent, a metal alkoxide. Examples thereof include a system crosslinking agent, a metal chelate crosslinking agent, a metal salt crosslinking agent, and an ammonium salt crosslinking agent. Furthermore, these polymerization initiators can be used in combination. Among them, the isocyanate-based crosslinking agent has an advantage of excellent reactivity with the hydroxyl group. A crosslinking agent can be used individually by 1 type or in combination of 2 or more types. The crosslinking agent can be used for the purpose of improving physical properties such as bending strength and bending elastic modulus of the CNF molded body, or for adding other functions to the CNF molded body.

The content of the additive is preferably 1% to 10% with respect to the solid content of the cellulose nanofiber. If it is 1% or less, it is conceivable that the crosslinking agent and the cellulose nanofibers do not react. If it is 10% or more, the crosslinking agent is excessive and the characteristics of the cellulose nanofiber may be reduced.

As the isocyanate-based crosslinking agent, polyfunctional isocyanate (refers to a compound having an average of two or more isocyanate groups per molecule, including those having an isocyanurate structure) can be preferably used. For example, aromatic polyisocyanates such as isocyanate acrylate or tolylene diisocyanate, diphenylmethane diisocyanate, xylylene diisocyanate, aliphatic polyisocyanates such as hexamethylene diisocyanate, alicyclic polyisocyanates such as isophorone diisocyanate, hydrogenated diphenylmethane diisocyanate, and the like Biuret bodies, isocyanurate bodies, and adduct bodies that are a reaction product with a low molecular active hydrogen-containing compound such as ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane, castor oil, and the like. An isocyanate type crosslinking agent can be used individually by 1 type or in combination of 2 or more types.

[Solvent substitution]
A CNF-containing slurry obtained by replacing the solvent of the CNF-containing slurry from an aqueous solvent to an organic solvent may be used. The organic solvent can be used without any particular limitation, for example, alcohols, saturated aliphatic hydrocarbons, esters, ethers, nitriles, aprotic polar solvents, ketones, amides, aromatic carbonization. Hydrogen, nitrogen-containing aromatic compound, ionic liquid, and water are preferable. For example, hexane, toluene, chloroform, dichloromethane, diethyl ether, THF, ethyl acetate, acetone, acetonitrile, DMF, DMSO, ethanol, methanol, acetic acid, methyl methacrylate, and the like can be used. By using a volatile solvent, the time required for dehydration can be reduced, and CNF can aggregate to improve dehydration.

As an example of the solvent substitution treatment method, an example of the substitution treatment with methanol is as follows. First, CNF and methanol in the same amount as the water contained in the CNF are mixed and stirred, and then the mixed stirring solution is vacuum filtered. The water is removed. Then, an appropriate amount of methanol is further supplied to the CNF obtained by this removal, and the CNF is evenly dispersed in the methanol solution. In addition, although the case where methanol was used as a substitution medium was illustrated here, it is also possible to perform the said substitution process using solvents other than methanol.

Of course, the method of solvent replacement is not limited to the above, and other methods can be employed. For example, the CNF-containing slurry may be freeze-dried to remove moisture in the CNF-containing slurry.

Next, the present invention will be described in more detail based on examples, but the present invention is not limited to the following examples. Unless otherwise specified, in the present invention,% and the like are based on weight, and the numerical range includes the end points.

Example 1
(Liquid temperature and amount of drainage of CNF-containing slurry)
Pure water is added to CNF1.816% aqueous dispersion (BB 5pass product) to dilute to 0.1% concentration, and 0.1% CNF aqueous solution is used at 12, 27.5, 50, and 80 ° C using a water bath. The drainage amount was measured by setting the temperature.
Here, the amount of drainage refers to the amount of water dehydrated in each time such as 10, 20, 30 min after suction filtration of 200 ml of 0.1% CNF dispersion. That is, the greater the amount of drainage, the better the dehydration and the less time for dehydrating the solvent.

Table 1 shows the results. As is apparent from Table 1, the amount of drainage increases as the liquid temperature increases. Therefore, the time for dehydrating the solvent can be shortened by heating the CNF-containing slurry. Therefore, the time required for solvent removal can be shortened by heating the mold part of the CNF molding apparatus in the present invention.

Example 2
(The amount of drainage of the CNF-containing slurry to which the metal salt is added)
Pure water is added to CNF1.816% aqueous dispersion (BB-5pass product) and diluted to a concentration of 0.1%, and tricalcium phosphate is blended at a ratio of 0, 1, 3, 5, 10%, The amount of drainage was measured for each CNF-containing slurry at room temperature.

Table 2 shows the results. As is apparent from Table 2, the amount of drainage increased by 5% rather than 3%. Therefore, the time required for solvent removal can be shortened by adding more than 3% of tricalcium phosphate.

Example 3
Using CNF 1.817% aqueous dispersion (BB-5 pass product), blended with water-dispersed pulp in advance so that the pulp has a prescribed blending ratio, 0.1% CNF and pulp The amount of filtrate in the aqueous dispersion was measured. The temperature was room temperature.

Table 3 shows the results. As apparent from Table 3, the amount of drainage increased when the pulp content was 10%. Moreover, when it was in the range of 30% or more, it was found that the drainage amount did not increase even if the pulp amount was increased. Therefore, a CNF-containing slurry having a pulp content of 10 to 30% can shorten the time required for solvent removal.

Example 4
(The amount of drainage of CNF-containing slurry substituted with an organic solvent)
Tricalcium phosphate 10% was added to the CNF 2% aqueous dispersion, and suction filtration was performed twice with methanol to obtain 2.5% methanol wet CNF. This was made into 0.1% CNF methanol solution, and it was set as Example 4. Comparative Example 2 was prepared by adding 10% tricalcium phosphate to a CNF 2% aqueous dispersion and diluting the resulting solution to 0.1%.
The amount of filtrate and solution stability evaluation apparatus (Eihiro Seiki Co., Ltd.) was used to measure the sedimentation rate.

Table 4 shows the result of the drainage amount, and Table 5 shows the measurement result of the sedimentation rate. As is clear from Table 4, in the example in which the methanol solvent was replaced, 200 ml could be filtered in 1 minute. In addition, from Table 5, it can be seen that Example 4 substituted with a methanol solvent has a higher sedimentation rate. Therefore, the CNF-containing slurry substituted with the organic solvent can shorten the time required for solvent removal.

Example 5
(CNF forming body using CNF-containing slurry of water solvent and cutting using this)
A CNF-containing slurry was prepared by mixing 7.91 kg of CNF 2% aqueous dispersion (158 g of CNF), 135.8 g (67.8 g) of 50% pulp and 11 g of calcium phosphate (5% with respect to the CNF compact). Subsequently, it put into the CNF shaping | molding apparatus using a cylindrical type | mold, the load 60kg and the metal mold | die part were set to 100 degreeC, and the molded object was created. The obtained CNF compact had a bottom diameter of 12 cm, a height of 20 mm, and a weight of 226 g. A denture base portion of a full denture was created using the CNF molded body obtained in this example. FIG. 2 shows a photograph of the molded body obtained by the CNF molding apparatus. FIG. 3 shows the CNF compact after cutting. As described above, according to the present invention, it is possible to obtain a molded body having a thickness that enables cutting and a uniform inside.

Example 6
(Preparation of CNF compact using CNF-containing slurry substituted with methanol solvent and cutting using the same)
The CNF 2% aqueous dispersion was 12.5 kg (CNF 250 g) and calcium phosphate 12.5 g (5% with respect to the CNF compact). Subsequently, it put into the CNF shaping | molding apparatus using a cylindrical type | mold, the load 60kg and the metal mold | die part were set to 100 degreeC, and the molded object was created. The obtained CNF compact had a bottom diameter of 12 cm, a height of 20 mm, and a weight of 256 g. A denture base portion of a full denture was created using the CNF molded body obtained in this example. FIG. 4 shows the CNF compact after cutting. As described above, according to the present invention, it is possible to obtain a molded body having a thickness that enables cutting and a uniform inside.

Examples 7 to 18
(Physical property evaluation of CNF compact)
CNF compacts were prepared and (1) three-point bending test, (2) surface hardness measurement (3) contact angle measurement, (4) water absorption measurement (5) density measurement. First, each measurement condition is described below.
(1) Three-point bending test CNF compacts obtained in each example were tested with a specimen size of 64 x 10 x 2 mm, using an Instron Japan material testing machine INSTRON5565, crosshead speed of 5 mm / min, distance between supports The test was conducted under the condition of 50 mm, and bending strength (MPa) and bending elastic modulus (MPa) were calculated.
(2) Measurement of surface hardness Using a hardness tester (Tecrock durometer type D, manufactured by Tecrock Co., Ltd.), three test pieces were measured for each of four locations. The pressure surface was brought into close contact so that the push needle was perpendicular to the test piece measurement surface, and the value (HDD) after 3 seconds was measured.
(3) Measurement of contact angle Using a fully automatic contact angle meter manufactured by Kyowa Interface Science Co., Ltd., the contact angle (°) 10 seconds after dropping of distilled water was measured by the droplet method. Ten points were measured, and an average of eight points excluding the maximum and minimum values was calculated.
(4) Measurement of water absorption The test piece was immersed in water, and the weight after 3 days was measured. The difference in weight after 3 days from the original weight was determined and used as the amount of water supply (μg / mm 3).
(5) Measurement of density The density was measured from the volume and weight of the test piece.

(Example 7)
2000 g of CNF 2% aqueous dispersion was used as a CNF-containing slurry. Subsequently, it put into the CNF shaping | molding apparatus using a cylindrical type | mold, the load 60kg and the metal mold | die part were set to 100 degreeC, and the molded object was created.

(Example 8)
About 4000 g of CNF 1% aqueous dispersion was subjected to suction filtration twice with methanol to obtain 2.6% methanol wet CNF to obtain a CNF-containing slurry. Subsequently, it put into the CNF shaping | molding apparatus using a cylindrical type | mold, the load 60kg and the metal mold | die part were set to 100 degreeC, and the molded object was created.

Example 9
To 2000 g of CNF 2% aqueous dispersion, 2 g of tricalcium phosphate (5% based on the solid content of CNF) was added to obtain a CNF-containing slurry. Subsequently, it put into the CNF shaping | molding apparatus using a cylindrical type | mold, the load 60kg and the metal mold | die part were set to 100 degreeC, and the molded object was created.

(Example 10)
To 2000 g of CNF 2% aqueous dispersion, 4 g of tricalcium phosphate (10% with respect to the solid content of CNF) was added to obtain a CNF-containing slurry. Subsequently, it put into the CNF shaping | molding apparatus using a cylindrical type | mold, the load 60kg and the metal mold | die part were set to 100 degreeC, and the molded object was created.

(Example 11)
To 1400 g of CNF 2% aqueous dispersion, 4 g of tricalcium phosphate (10% with respect to the total solid content of CNF and pulp) and bamboo pulp were added so that the weight ratio of CNF to pulp was 7: 3. It was. Subsequently, it put into the CNF shaping | molding apparatus using a cylindrical type | mold, the load 60kg and the metal mold | die part were set to 100 degreeC, and the molded object was created.

(Example 12)
A 2000% CNF 2% aqueous dispersion was subjected to suction filtration twice with methanol to obtain 2.5% methanol wet CNF. To this, 2 g of tricalcium phosphate (5% based on CNF solid content) was added to obtain a CNF-containing slurry. Subsequently, it put into the CNF shaping | molding apparatus using a cylindrical type | mold, the load 60kg and the metal mold | die part were set to 100 degreeC, and the molded object was created.

(Example 13)
5 mL of a mixed solution of 94% DMSO / 6% water (v / v) containing 1.5% (w / v) CNF aqueous dispersion and potassium carbonate (vs. pulp weight 20%) was added at room temperature until a good dispersion was obtained. Stir with. Next, after dispersion, the mixture was heated to 70 ° C., vinyl laurate was added and sealed so as to be equivalent to 1.2 mol per anhydroglucose unit (AGU), and the mixture was reacted for 2 hours at 70 ° C.
Then, it wash | cleaned and it was set as the methyl methacrylate solution wet CNF. This was made into a 2% CNF methyl methacrylate solution to make a CNF-containing slurry.
Subsequently, it put into the CNF shaping | molding apparatus using a cylindrical type | mold, the load 60kg and the metal mold | die part were set to 100 degreeC, and the molded object was created.

(Example 14)
Stir 5 mL of a mixed solution of 94% DMSO / 6% water (v / v) containing 1% (w / v) CNF aqueous dispersion and potassium carbonate (vs. pulp weight 20%) at room temperature until a good dispersion is obtained. did. Next, after dispersion, the mixture was heated to 70 ° C., vinyl laurate was added and sealed so as to be equivalent to 1.2 mol per anhydroglucose unit (AGU), and the mixture was reacted for 2 hours at 70 ° C.
Then, it wash | cleaned and it was set as the methyl methacrylate solution wet CNF. This was made into a 2% CNF methyl methacrylate solution, and what added 2 g of isocyanate acrylates (Laromer LR9000 for dual cure manufactured by BASF) (5% with respect to the solid content concentration of CNF) was used as a CNF-containing slurry. Subsequently, it put into the CNF shaping | molding apparatus using a cylindrical type | mold, the load 60kg and the metal mold | die part were set to 100 degreeC, and the molded object was created.

(Example 15)
4000 g of CNF 1% aqueous dispersion was subjected to suction filtration twice with methanol to obtain about 2.6% methanol wet CNF. To this, 2 g of isocyanate acrylate (Laromer LR9000, dual cure acrylate manufactured by BASF) (5% based on CNF solid content) was added to obtain a CNF-containing slurry. Subsequently, it put into the CNF shaping | molding apparatus using a cylindrical type | mold, the load 60kg and the metal mold | die part were set to 100 degreeC, and the molded object was created.

(Example 16)
4000 g of CNF 1% aqueous dispersion was subjected to suction filtration twice with methanol to obtain about 2.6% methanol wet CNF. This was dissolved in methanol in 4 g of isocyanate acrylate (Laromer LR9000, dual cure acrylate manufactured by BASF) (10% based on CNF solid content), and added to obtain a CNF-containing slurry. Subsequently, it put into the CNF shaping | molding apparatus using a cylindrical type | mold, the load 60kg and the metal mold | die part were set to 100 degreeC, and the molded object was created.

(Example 17)
A 4000% CNF aqueous dispersion was subjected to suction filtration with methanol twice to obtain about 2.4% methanol wet CNF. To this, 2 g of isocyanate acrylate (BASF acrylate Laromer LR9000) (5% based on CNF solid content) was dissolved in methanol, and 100 mg of a polymerization initiator (Wako Pure Chemical Industries, Ltd. V-65) was added. Thus, a CNF-containing slurry was obtained. Subsequently, it put into the CNF shaping | molding apparatus using a cylindrical type | mold, the load 60kg and the metal mold | die part were set to 100 degreeC, and the molded object was created.

(Example 18)
CNF 1% aqueous dispersion 4000g, suction filtered twice with acetone to make about 2.4% acetone solution, 2g of isocyanate acrylate (BASF's dual cure acrylate Laromer LR9000) (5% to CNF solid content) Was dissolved in acetone, and 100 mg of a polymerization initiator (V-65 manufactured by Wako Pure Chemical Industries, Ltd.) was further added to obtain a CNF-containing slurry. Subsequently, it put into the CNF shaping | molding apparatus using a cylindrical type | mold, the load 60kg and the metal mold | die part were set to 100 degreeC, and the molded object was created.

For Examples 7, 8, 9, 10, 11, 12, 15, 16, 17, and 18, the above-mentioned (1) three-point bending test and (5) density measurement were performed. Moreover, as Comparative Example 3, a test piece of the same size was prepared using an acrylic resin and measured together.

Table 6 shows the results. As can be seen from the table, the flexural modulus values were higher for all examples. In Examples 10, 11, and 12, since the density is low, it is not possible to add a metal salt, a pulp, or both to a CNF-containing slurry in a product field where low density is required. Is very useful.

For Examples 15, 16, 17, and 18, the above-described (2) surface hardness test was performed. Moreover, it measured together using the acrylic resin used as the comparative example 3.

Table 7 shows the results. As can be seen from Table 7, the values were almost the same as or higher than those of the comparative example.

For Examples 13 and 14, the above-described (3) measurement of contact angle and (5) measurement of density were performed. Moreover, it measured together using the acrylic resin used as the comparative example 3.

Table 8 shows the results. As can be seen from Table 8, the contact angle was larger than that of the comparative example. As a result, it was possible to maintain the hydrophobicity of the CNF compact.

For Examples 7, 13, 14, 15, 16, 17, and 18, the water absorption amount of (4) described above was measured. For the results of 1500 μg / mm 3 or more, the evaluation criterion “unmeasured” was adopted.

Table 9 shows the results. As can be seen from Table 9, in Example 7, the result was “unmeasured”, but in other examples, good results were obtained. From the results of Examples 13 and 14, it is clear that the CNF compact using hydrophobic CNF has sufficient hydrophobicity, and from the results of Examples 15, 16, 17, and 18, It was revealed that hydrophobicity can be imparted to the CNF compact without using modified CNF.

Claims (15)

1. In a CNF molding apparatus that applies a load using vapor permeation means that allows vapor to permeate through a slurry containing cellulose nanofiber (hereinafter referred to as CNF), the molding includes a molding die that forms a molding cavity with a main body and a bottom plate, and the molding A CNF forming apparatus comprising a CNF throwing means for the cavity, wherein the bottom plate can be fitted inside the main body, and has a pressurizing means for pressing the main body toward the bottom plate.
2. 2. The CNF molding apparatus according to claim 1, wherein the bottom plate uses a vapor transmission means at least partially.
3. The main body portion includes a mold portion and an upper plate, and the upper plate is disposed on the opposite side of the bottom plate via the mold portion, and the mold portion is added in the direction of the bottom plate by the upper die. The CNF molding apparatus according to claim 1 or 2, wherein the pressurization is possible.
4. 4. The CNF molding apparatus according to claim 3, wherein the upper plate and the mold part are formed by using vapor transmission means at least in part.
5. The CNF molding apparatus according to claim 3 or 4, wherein heating means for the mold part is provided.
6. In a CNF molding method in which a load is applied using vapor transmission means for allowing vapor to pass through the CNF-containing slurry, a molding die for forming a molding cavity is formed by a main body portion and a bottom plate, and CNF charging means for the molding cavity is provided. The CNF molding method is characterized in that the bottom plate can be fitted inside the main body, and the main plate is pressed in the direction of the bottom plate.
7. 8. The CNF molding method according to claim 7, wherein the bottom plate uses a vapor transmission means at least in part.
8. The main body portion includes a mold portion and an upper plate, and the upper plate is disposed on the opposite side of the bottom plate via the mold portion, and the mold portion is added in the direction of the bottom plate by the upper die. The CNF molding method according to claim 6, further comprising a pressing step.
9. The CNF molding method according to claim 8, wherein the upper plate and the mold part are formed by using a vapor transmission means at least in part.
10. The CNF molding method according to claim 8 or 9, wherein heating means for the mold part is provided.
11. The CNF-containing slurry is a CNF-containing slurry containing CNF having an average thickness of 3 to 200 nm and an average length of 0.1 μm or more in a range of 2 to 10% in an aqueous solvent and / or an organic solvent. The CNF molding method according to any one of claims 6 to 10.
12. The CNF-containing slurry according to any one of claims 6 to 10, wherein the CNF-containing slurry according to claim 11 is a CNF-containing slurry further containing a metal salt in a range of 3 to 10%. Method.
13. The CNF-forming slurry according to any one of claims 6 to 10, wherein the CNF-containing slurry according to claim 11 is a CNF-containing slurry further containing pulp in a range of 10 to 30%. .
14. The CNF-containing slurry according to claim 11, wherein the CNF-containing slurry contains pulp in a range of 10 to 30% and further contains a metal salt in a range of 3 to 10%. Item 11. The CNF molding method according to any one of Items 10.
15. The CNF-forming method according to any one of claims 6 to 10, wherein the CNF-containing slurry according to claims 11 to 14 is further converted into a CNF-containing slurry containing a crosslinking agent.

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