JP5609599B2 - Fine fibrous cellulose-containing sheet paper making wire and method for producing fine fibrous cellulose-containing sheet - Google Patents

Description

  An object of this invention is to provide the manufacturing method of the fine fiber cellulose containing sheet | seat using the paper making wire used when making a fine fibrous cellulose into a sheet by a papermaking method, and the paper making wire.

In recent years, materials using reproducible natural fibers have attracted attention due to the substitution of petroleum resources and the growing environmental awareness. Among natural fibers, cellulose fibers having a fiber diameter of 10 to 50 μm, especially wood-derived cellulose fibers (pulp) have been widely used as paper products so far.
In addition, fine fibrous cellulose having a fiber diameter of 1 μm or less is also known as the cellulose fiber, and the sheet containing the fine fibrous cellulose has advantages such as high mechanical strength, and can be used for various applications. Application is under consideration.

As a method for producing a fine fibrous cellulose-containing sheet, Patent Documents 1 to 3 disclose that fine fibrous cellulose is made with a conventional paper making wire. However, in this method, since fine fibrous cellulose cannot be sufficiently captured by the papermaking wire, sufficient filtration efficiency cannot be obtained and the yield is low. In particular, fine fibrous cellulose having an average fiber diameter of 2 to 200 nm and an average fiber length of 0.01 to 100 μm was hardly captured by a conventional papermaking wire and could not be formed into a sheet.
Patent Documents 4 to 6 disclose a method in which a fine fibrous cellulose suspension is cast on glass, a resin plate, a metal plate, etc., and dried to form a sheet. However, this method requires energy and time for drying to form a sheet, and tends to increase the cost.
Moreover, in patent documents 7 and 8, in order to industrially produce a fine fibrous cellulose-containing sheet, a nonwoven fabric or a woven fabric comprising a filter cloth or organic polymer fiber having a denseness (a constant air permeability range), Alternatively, it has been proposed to use a porous membrane filter cloth containing an organic polymer as a papermaking wire. However, in the above-mentioned filter cloth, woven fabric and non-woven fabric, when the water permeability is increased, the fine fibrous cellulose cannot be sufficiently captured and the yield is lowered. In addition, the filter cloth, the woven fabric, and the nonwoven fabric are difficult to recycle after being used once for filtration, and are expensive. Therefore, when the filter cloth is disposable, the manufacturing cost increases. Further, when the above filter cloth, woven fabric and non-woven fabric are used as a papermaking wire, the surface quality of the fine woven cellulose sheet may be insufficient.

  Further, as a method for filtering and dewatering a fine fibrous cellulose suspension to form a sheet, a method using a filter paper having many fine pores or a membrane filter which is a film filter is also known. Clogging is likely to occur, and the filtration time tends to be longer.

Japanese Patent No. 3036354 Japanese Patent Laid-Open No. 10-140493 JP-A-8-188980 JP-A-5-148387 JP 2001-279016 A JP 2007-23218 A JP 2006-193858 A International Publication No. 2006/004012

  It is an object of the present invention to provide a paper making wire and a method for producing a fine fibrous cellulose-containing sheet, which can produce a fine fibrous cellulose-containing sheet with good surface quality at a low cost without impairing yield and productivity. To do.

The present invention has the following configuration.
[1] at least one surface of the paper substrate, Ri Do from sheet hydrophobized and surface smoothness by hydrophobizing agent is a hydrophobic smooth surface more than 50 seconds, the fine in the hydrophobic smooth surface microfibrous cellulose-containing sheet papermaking wires to a cellulose-containing sheet, wherein the paper to Rukoto.
[2] The fine fibrous cellulose-containing sheet paper making wire according to [1], wherein the surface smoothness of the hydrophobized smooth surface is 200 to 800 seconds.
[3] The fine paper according to [1] or [2], wherein the paper base material is single glossy paper having a glossy surface on one side, and the glossy surface is hydrophobized to be a hydrophobic smooth surface. Fibrous cellulose-containing sheet paper making wire.
[4] Any of [1] to [3], wherein the hydrophobizing agent is at least one selected from the group consisting of a silicone compound, a fluorine compound, a polyolefin wax, a higher fatty acid amide, a higher fatty acid alkali salt, and an acrylic polymer. The wire for papermaking of a fine fibrous cellulose containing sheet | seat of Claim 1.
[5] A fine fiber having a squeezing step of obtaining a water-containing web by filtering and dewatering a suspension containing fine fibrous cellulose and water using a papermaking wire, and a drying step of drying the water-containing web. A method for producing a cellulose-containing sheet, wherein in the squeezing step, the fine fibrous cellulose-containing sheet paper making wire according to any one of [1] to [4] is used as the paper making wire. A method for producing a fine fibrous cellulose-containing sheet, characterized in that a suspension is supplied to the hydrophobic smooth surface of the fine fibrous cellulose-containing sheet papermaking wire.

  According to the method for producing a papermaking wire and a fine fibrous cellulose-containing sheet of the present invention, a fine fibrous cellulose-containing sheet with good surface quality can be produced at low cost without impairing yield and productivity.

It is a schematic block diagram of one Embodiment of the manufacturing apparatus used with the manufacturing method of the fine fibrous cellulose containing sheet | seat of this invention.

<Wire for fine fiber cellulose containing sheet paper>
The fine fibrous cellulose-containing sheet paper making wire of the present invention (hereinafter abbreviated as “paper making wire”) is a suspension containing fine fibrous cellulose (hereinafter referred to as “fine fibrous cellulose suspension”). Is used to produce a fine fibrous cellulose-containing sheet by filtration, and at least one surface of the paper substrate is hydrophobized by a hydrophobizing agent and has a surface smoothness of 50 seconds or more. It is a sheet having a hydrophobized smooth surface.
The paper base is easier to ensure water permeability when the other surface is not smoothed. Moreover, it is easier to ensure water permeability when the other surface of the paper base is not hydrophobized. Therefore, a fine fibrous cellulose-containing sheet can be produced with higher productivity by making only one surface of the paper substrate a hydrophobic smooth surface. From an economical viewpoint, it is preferable that only one surface of the paper base material is a hydrophobic smooth surface.

(Paper substrate)
Examples of the paper substrate include glossy paper, high-quality paper, medium-quality paper, copy paper, art paper, coated paper, kraft paper, paperboard, white paperboard, newsprint paper, and renewal paper.
Among the paper base materials, it is preferable to use glossy paper and make the glossy surface hydrophobic. Here, the single glossy paper is obtained by drying wet paper after paper making with a Yankee dryer, and one side has a glossy surface with high gloss. Moreover, the surface (further surface) side opposite to the glossy surface has a lower density than the glossy surface side. Therefore, it is possible to ensure sufficient air permeability while obtaining high smoothness on the glossy surface, so if paper is made of fine fibrous cellulose with a hydrophobic glossy surface, the surface quality is better without reducing the filtration rate. A fine fibrous cellulose-containing sheet can be easily obtained.

The paper base is obtained by making a paper stock containing pulp with a paper machine or hand-making. The pulp may be wood pulp or non-wood pulp. Examples of the raw material for wood pulp include conifers and hardwoods, but it is preferable to contain a large amount of pulp made from hardwoods in terms of increasing the smoothness of the paper base.
The pulp may be either mechanical pulp or chemical pulp. As chemical pulp, kraft pulp (KP, cooking liquor: NaOH and Na ₂ S), polysulfide pulp (SP, cooking liquor: NaOH and Na ₂ S _X ), soda pulp (digestion liquid: NaOH), sulfite pulp (digestion) Liquid: Na ₂ SO ₃ ), sodium carbonate pulp (cooking liquid: Na ₂ CO ₃ ), oxygen soda pulp (cooking liquid: O ₂ and NaOH), and the like. Among these, kraft pulp is preferable in terms of smoothness and cost.
The pulp may be unbleached pulp or bleached pulp.
The pulp may be either unbeaten pulp or beaten pulp, but beating pulp is preferable in terms of improving the smoothness of the paper base material. The Canadian standard freeness of the beaten pulp measured according to JIS P8121 is preferably 40 to 450 ml, more preferably 60 to 400 ml, and particularly preferably 80 to 380 ml. If the Canadian standard freeness of the beaten pulp is equal to or higher than the lower limit, the air permeability of the paper substrate becomes lower (the air permeability becomes higher), and the dehydration rate of the fine fibrous cellulose suspension becomes higher. If it is below the upper limit, the smoothness of the paper base material becomes higher.

The paper stock may contain additives such as paper strength agents such as starch and polyacrylamide, rosin sizing agents, alkenyl ketene dimer sizing agents, ASA sizing agents, sulfuric acid bands and wax emulsions. Among these, since the surface strength of the papermaking wire is increased, it is preferable to include a paper strength agent. When the surface strength of the papermaking wire increases, the peelability of the fine fibrous cellulose-containing sheet increases in the production of the fine fibrous cellulose-containing sheet described below.
Further, a sizing agent or a wax emulsion is preferable because the water resistance of the papermaking wire is improved. If the water resistance of the papermaking wire is high, the filtration time of the fine fibrous cellulose suspension is shortened in the production of the fine fibrous cellulose-containing sheet, and it is difficult to break.

  Examples of the paper machine used for paper making include continuous paper machines such as a long-mesh type, a circular net type, and an inclined type used in ordinary paper making, and a multilayer paper making machine combining these.

The surface smoothness (measured by Oken-style smoothness (JAPAN TAPPI paper pulp test method, No. 5-2: 2000)) of at least one surface of the paper base to be hydrophobized is 100 seconds or more. Preferably, it is 150 to 700 seconds. If the surface smoothness of at least one surface of the paper base to be hydrophobized is equal to or higher than the lower limit, a fine fibrous cellulose-containing sheet having good surface quality in the production of the fine fibrous cellulose-containing sheet described below. If the surface smoothness can be easily obtained and the surface smoothness is not more than the above upper limit value, a papermaking wire in which a decrease in the productivity of the fine fibrous cellulose-containing sheet can be easily obtained.
20-500 seconds are preferable and, as for the Oken type | formula air permeability (JAPAN TAPPI paper pulp test method No.5-2: 2000) of a paper base material, it is more preferable that it is 40-250 seconds. If the air permeability of the paper substrate is equal to or higher than the lower limit value, fine fibrous cellulose can be captured more, and if it is equal to or lower than the upper limit value, a paper making wire in which a decrease in productivity of the fine fibrous cellulose-containing sheet is prevented. Can be easily obtained.
The basis weight of the paper substrate is preferably from 30~300g / ^{m 2,} and more preferably 50 to 250 g / ^{m 2.} If the basis weight of the paper substrate is equal to or greater than the lower limit value, a papermaking wire capable of sufficiently capturing fine fibrous cellulose can be obtained more easily. If the basis weight of the paper substrate is equal to or less than the upper limit value, Thus, it is possible to more easily obtain a papermaking wire in which the productivity of the fine fibrous cellulose-containing sheet is prevented from being lowered.
Among paper substrate, the basis weight of Katatsuyashi is preferably from 15~300g / ^{m 2,} and more preferably 20 to 200 g / ^{m 2.} If the basis weight of single glossy paper is equal to or higher than the lower limit value, a papermaking wire capable of sufficiently capturing fine fibrous cellulose can be obtained more easily. If the basic weight of single glossy paper is equal to or lower than the upper limit value, Thus, it is possible to more easily obtain a papermaking wire in which the productivity of the fine fibrous cellulose-containing sheet is prevented from being lowered.

(Hydrophobicizing agent)
A hydrophobizing agent is a substance that has a low affinity for water and is difficult to dissolve or mix in water. Specifically, the drug has a water contact angle measured as follows of 90 ° or more.
・ Measuring method of contact angle The drug is applied to the surface of corona-treated polyethylene terephthalate at a coating amount of 1 g / m ² , distilled water is dropped on the surface of the coated drug, and after 1 minute, a dynamic contact meter is used. Measure the contact angle.

  The hydrophobizing agent is at least one selected from the group consisting of a silicone compound, a fluorine compound, a polyolefin wax, a higher fatty acid amide, a higher fatty acid alkali salt, and an acrylic polymer because the releasability of the wire can be increased. The silicone compound is more preferable because it is more excellent in releasability. In the present specification, “silicone compound” refers to polysiloxane.

Among the silicone compounds, linear dimethylpolysiloxane is preferable because of particularly excellent releasability. Furthermore, among linear dimethylpolysiloxanes, those that are low in crystallinity and do not become solid at room temperature, and are preferably thermosetting and active energy ray curable (UV curable, electron beam curable). Examples of the thermosetting dimethylpolysiloxane include a condensation type and an addition reaction type.
Condensation-type thermosetting dimethylpolysiloxane is a product that reacts and condenses silanol-functional long-chain dimethylpolysiloxane at both ends with methylhydrogenpolysiloxane or methylmethoxypolysiloxane in the presence of an organotin catalyst. Can be mentioned.
Examples of the addition reaction type thermosetting dimethylpolysiloxane include those obtained by reacting a linear methylvinylpolysiloxane having a vinyl group with methylhydrogenpolysiloxane in the presence of a platinum-based catalyst.
Also, as thermosetting dimethylsiloxane, solvent type, emulsion type, or solventless type diluted with toluene or n-hexane can be used, but it is easy to apply to pot life, glossy paper, and impregnation. Therefore, the emulsion type is preferable.
Examples of the active energy ray-curable dimethylpolysiloxane include dimethylpolysiloxane having an acryloyl group.

  Examples of other silicone compounds include dimethylpolysiloxane compounds having a mercapto group and an unsaturated double bond, and dimethylpolysiloxane compounds having an epoxy group.

Examples of the fluorine compound include polytetrafluoroethylene.
Examples of the polyolefin wax include paraffin wax, carnauba wax, microcrystalline wax, polyethylene wax, polypropylene wax, and oxidized polyethylene wax.
Examples of the higher fatty acid amide include oleic acid amide, erucic acid amide, stearic acid amide, behenic acid amide, and ethylene bis stearic acid amide.
Examples of higher fatty acid alkali salts include calcium stearate, zinc stearate, potassium oleate, and ammonium oleate.
Examples of the acrylic polymer include homopolymers or copolymers of (meth) acrylic acid alkyl ester monomers such as methyl acrylate, n-butyl acrylate, methyl methacrylate, and n-butyl methacrylate, the (meth) acrylic. Examples thereof include a copolymer of an acid alkyl ester monomer and another vinyl polymerizable monomer such as styrene or butadiene.
The said compound may be used individually by 1 type, and may use 2 or more types together.

  The hydrophobizing agent may be contained in the entire paper base, or may be unevenly distributed on the surface side (both sides or one side). It is preferable that the hydrophobizing agent is unevenly distributed on the surface side in that sufficient peelability can be obtained with a small amount of the hydrophobizing agent used.

(Physical properties of paper making wire)
As described above, the hydrophobized smooth surface of the papermaking wire has a surface smoothness (measured by the Oken type smoothness (JAPAN TAPPI paper pulp test method, No. 5-2: 2000)) of 50 seconds or more. The surface smoothness of the hydrophobic smooth surface is preferably 200 to 800 seconds, more preferably 200 to 700 seconds.
When the surface smoothness of the hydrophobized smooth surface is less than the lower limit, the releasability of the fine fibrous cellulose-containing sheet is lowered in the production of the fine fibrous cellulose-containing sheet described later, and the surface quality is lowered. On the other hand, when the surface smoothness exceeds the upper limit, the fine pores on the surface of the paper substrate are blocked by fibers or hydrophobizing agents, and the dehydration time of the fine fibrous cellulose suspension is increased. There is a fear.

  The papermaking wire preferably has a Wangken air permeability (JAPAN TAPPI paper pulp test method No. 5-2: 2000) of 50 to 300 seconds. If the air permeability of the papermaking wire is equal to or higher than the lower limit value, fine fibrous cellulose can be captured more, and if it is equal to or lower than the upper limit value, the water permeability becomes higher, and the production of the fine fibrous cellulose-containing sheet described later is performed. The filtration time in can be further shortened.

In order to set the surface smoothness and air permeability of the papermaking wire within the above ranges, the surface smoothness of the paper substrate and the amount of the hydrophobizing agent may be appropriately selected. The higher the surface smoothness of the paper substrate and the greater the amount of the hydrophobizing agent, the higher the surface smoothness and the lower the air permeability.
In addition, the surface smoothness and air permeability of the papermaking wire can be adjusted by applying a surface treatment such as calendering during the manufacture of the papermaking wire and adjusting the treatment conditions. For example, the higher the calendar pressure, the higher the surface smoothness and the lower the air permeability.

Preferably the basis weight of the papermaking wire is 20 to 300 g / ^{m 2,} and more preferably 50 to 250 g / ^{m 2.} If the basis weight of the papermaking wire is equal to or more than the lower limit, sufficient strength can be secured and breakage is difficult. On the other hand, if the basis weight of the papermaking wire is equal to or less than the above upper limit value, sufficient flexibility can be ensured, and handleability is improved.

(Manufacturing method of paper making wire)
The method for producing a papermaking wire includes a hydrophobizing step of hydrophobizing at least one surface of a paper substrate with a hydrophobizing agent.
As a hydrophobizing method, a paint containing a hydrophobizing agent and a dispersion medium (hereinafter referred to as “hydrophobizing agent paint”) is applied to at least one surface side of a paper base material and dried. Examples include a method of impregnating a paper base material with a hydrophobizing agent paint and drying, and a method of applying a hydrophobizing agent paint on the surface of the wet paper for producing the paper base material and then drying it.
The dispersion medium contained in the hydrophobizing agent coating may be water, an organic solvent (for example, hydrocarbon, alcohol, ether, ketone, etc.), or a mixture of water and an organic solvent.

In the case of applying the hydrophobizing agent coating, examples of the coating apparatus include a blade coater, an air knife coater, a roll coater, a bar coater, a gravure coater, a rod blade coater, a lip coater, a curtain coater, and a die coater.
Preferably dry coating amount of hydrophobizing agent is 1 to 10 g / ^{m 2,} more preferably 0.1-5 g / ^{m 2,} further preferably 0.2 to 2 g / ^{m 2} . If the coating amount is at least the lower limit value, the fine fibrous cellulose-containing sheet can be easily peeled off, and if the coating amount is at most the upper limit value, the effect can be sufficiently obtained and the cost increase can be suppressed.
When glossy paper is used as the paper substrate, it is preferable to apply a hydrophobizing agent coating to the glossy surface. If the glossy surface of single glossy paper is hydrophobized, a papermaking wire with better surface quality can be obtained. Moreover, it is preferable not to apply a hydrophobizing agent to the further surface of the glossy paper, and to make only the glossy surface a hydrophobic smooth surface. By making only the glossy surface a hydrophobized smooth surface, water permeability can be further improved.
Drying of the hydrophobizing agent paint can be performed by normal heat drying with hot air, heat drying by infrared irradiation, vacuum drying, or natural drying. Further, after drying to some extent, it may be dried with a Yankee dryer. By drying using a Yankee dryer, the smoothness of the surface in contact with the Yankee dryer can be further improved.

  After the hydrophobizing agent coating is applied to the paper substrate, a finishing process may be performed using a calendar such as a machine calendar, a super calendar, or a soft calendar. When the finishing treatment is performed, the smoothness of the papermaking wire is improved, and the surface quality of the fine fibrous cellulose-containing sheet obtained using the papermaking wire is further improved.

In the case of impregnating the entire paper base material with the hydrophobizing agent paint, a method of immersing the paper base material in a tank in which a size press or a hydrophobizing agent paint is placed may be mentioned. In this method, since the hydrophobizing agent permeates from the surface of the paper substrate, it can be hydrophobized from the surfaces on both sides. When the impregnation time is increased, the entire paper base material contains a hydrophobizing agent, but it is sufficient that the hydrophobizing agent is included only on the surface side, and therefore it is not always necessary to increase the impregnation time. .
The amount of the hydrophobizing agent impregnated is preferably 0.01 to 10 parts by mass, and more preferably 0.1 to 5 parts by mass with respect to 100 parts by mass of the paper base material. If the amount of impregnation is equal to or greater than the lower limit, the fine fibrous cellulose-containing sheet can be easily peeled off, and if the amount of impregnation is equal to or smaller than the upper limit, the effect can be sufficiently obtained and the cost increase can be suppressed.
The finishing treatment may also be performed after the paper substrate is impregnated with the hydrophobizing agent coating.

The size press method is preferred when drying after applying the hydrophobizing agent to the surface in the wet paper stage for producing the paper base, and the coating amount at that time is the method of applying the hydrophobizing agent paint to the paper base It is the same. The drying method is the same as the method of applying the hydrophobizing agent paint to the paper base, but using a Yankee dryer, a glossy surface with a hydrophobic and smooth surface can be easily obtained. It can dry so that the surface which apply | coated the hydrophobizing agent may contact the surrounding surface of this.
In addition, after applying the hydrophobizing agent paint, a finishing process using a calendar may be performed in the same manner as the method of applying the hydrophobizing agent paint to the paper substrate.

(Function and effect)
The hydrophobized smooth surface of the paper making wire has high peelability and high surface smoothness with a surface smoothness of 50 seconds or more. Therefore, the fine fibrous cellulose-containing sheet formed on the hydrophobized smooth surface is broken. It can be made to peel without. Thereby, the fine fibrous cellulose containing sheet | seat of favorable surface quality can be obtained easily.
In addition, papermaking wire mainly composed of paper base material has a moderately low air permeability, so it plays the role of a filtration membrane and sufficiently captures fine fibrous cellulose when the fine fibrous cellulose suspension is filtered. And the yield is not easily lost.
Further, since the paper base material is inexpensive, the papermaking wire mainly composed of this can be made disposable, and the fine fibrous cellulose suspension can always be filtered by a new papermaking wire. Therefore, a sufficient filtration rate (productivity) can be secured, and filtration can be performed at low cost.
The papermaking wire can be recycled in the same way as ordinary paper.

<Fine fibrous cellulose-containing sheet>
The fine fibrous cellulose-containing sheet obtained by the method for producing a fine fibrous cellulose-containing sheet of the present invention is a sheet on which fine fibrous cellulose is made.
Here, the fine fibrous cellulose is an aggregate of cellulose molecules having a width (diameter) of 2 nm to 1000 nm as measured by observation with a scanning or transmission electron microscope. Such fine fibrous cellulose is a fiber or rod-like particle whose width is significantly smaller than that of pulp fiber used in ordinary papermaking applications. When the width of the fibrous cellulose is less than 2 nm, it dissolves in water as cellulose molecules, so that the physical properties (strength, rigidity, dimensional stability) as fine fibers do not appear. On the other hand, if the width exceeds 1000 nm, it cannot be said to be a fine fiber, and is a fiber contained in ordinary pulp, and physical properties (strength, rigidity, dimensional stability) as a fine fiber cannot be obtained.

Examples of a method for obtaining fine fibrous cellulose include wet grinding using mechanical action such as a grinder (stone mill type grinder), a high-pressure homogenizer, an ultra-high pressure homogenizer, a high-pressure collision type grinder, a disk type refiner, a conical refiner, and the like. A method of refining cellulosic fibers can be mentioned.
Further, it may be refined after chemical treatment such as 2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPO) oxidation, enzyme treatment, and ozone treatment.
Examples of cellulosic fibers to be refined include plant-derived cellulose, animal-derived cellulose, and bacterial-derived cellulose. More specifically, it is isolated from wood-based paper pulp such as conifer pulp and hardwood pulp, cotton pulp such as cotton linter and cotton lint, non-wood pulp such as hemp, straw and bagasse, sea squirt and seaweed. A cellulose etc. are mentioned. Among these, wood-based paper pulp and non-wood pulp are preferable in terms of easy availability.

  The fine fibrous cellulose-containing sheet may contain a sizing agent, a paper strength enhancer, a filler, and the like as required in general paper.

<Method for producing fine fibrous cellulose-containing sheet>
An embodiment of the method for producing a fine fibrous cellulose-containing sheet of the present invention will be described. The method for producing a fine fibrous cellulose-containing sheet of the present embodiment is a method of filtering a fine fibrous cellulose suspension using the papermaking wire, dewatering it to obtain a water-containing web, and drying the water-containing web A drying step.

(manufacturing device)
As an apparatus for producing a fine fibrous cellulose-containing sheet, for example, as shown in FIG. 1, a squeezing section 20, a drying section 40 provided on the downstream side of the squeezing section 20, and a downstream of the drying section. The manufacturing apparatus 1 including the winding section 60 provided on the side can be used.

The squeezed section 20 is a section for squeezing the fine fibrous cellulose suspension 3a using the papermaking wire 10 to obtain the water-containing web 3b.
The squeezing section 20 includes a feeding reel 21 for feeding out the papermaking wire 10 so that the hydrophobic smooth surface faces upward, a discharge portion 20a of the fine fibrous cellulose suspension 3a, and a squeezing portion 30 of the dispersion medium. Is provided.
The discharge unit 20 a includes a plurality of die heads 22 that discharge the fine fibrous cellulose suspension 3 a to the hydrophobic smooth surface of the papermaking wire 10 that is being fed from the delivery reel 21, and downstream of each die head 22. A plate 24 for leveling the upper surface of the fine fibrous cellulose suspension 3a disposed and discharged is provided.
The discharge unit 20a and the water squeezing unit 30 are provided with suction devices 26 and 32 for forcibly squeezing the dispersion medium from the fine fibrous cellulose suspension 3a. The suction devices 26 and 32 are disposed below the paper making wire 10, and a plurality of suction holes (not shown) connected to a vacuum pump (not shown) are formed on the upper surface thereof. However, it is preferable that the suction hole is not formed on the upstream side of the suction device 26 and is a non-suction hole that is not connected to the vacuum pump. If the suction hole is formed on the upstream side, the surface of the coating film of the fine fibrous cellulose suspension 3a may become rough. Moreover, since the amount of squeezing decreases on the downstream side, the suction device 32 in the squeezing unit 30 may not have a hole formed on the downstream side.

The drying section 40 is a section that obtains the fine fibrous cellulose-containing sheet 3c by drying the hydrous web 3b using a dryer.
The drying section 40 is provided in a hood 49 with a first dryer 42 and a second dryer 52 configured by cylinder dryers, and a felt cloth 44 disposed along the outer periphery of the first dryer 42. The first dryer 42 is disposed on the upstream side of the second dryer 52. Further, the felt cloth 44 is endless and is circulated by a guide roll 46.
In the drying section 40, the water-containing web 3 b is transferred by the guide roll 48. Specifically, first, a surface A (hereinafter referred to as “applied surface A”) of the water-containing web 3b on which the fine fibrous cellulose suspension 3a is applied is in contact with the outer peripheral surface of the first dryer 42, and the water-containing web 3b. The fine fibrous cellulose suspension 3a is not applied to the surface B (hereinafter referred to as “non-application surface B”) so as to contact the felt cloth 44, and then the application surface A of the second dryer 52 It comes in contact with the outer peripheral surface.

The winding section 60 is a section for separating the fine fibrous cellulose-containing sheet 3c from the papermaking wire 10 and winding it.
In the winding section 60, a pair of separation rollers 62a and 62b for separating the fine fibrous cellulose-containing sheet 3c from the papermaking wire 10, a take-up reel 64 for winding the fine fibrous cellulose-containing sheet 3c, and a used reel A collection reel 66 that winds and collects the papermaking wire 10 is provided. The separation roller 62b is disposed on the papermaking wire 10 side, and the separation roller 62a is disposed on the fine fibrous cellulose-containing sheet 3c side.

(Water extraction process)
In the squeezing step, the papermaking wire 10 is fed out from the delivery reel 21, the fine fibrous cellulose suspension 3 a is discharged from the die head 22 onto the hydrophobic smooth surface of the papermaking wire 10, and the fine fibrous cellulose of the papermaking wire 10 is discharged. The upper surface of the suspension 3 a is leveled by the plate 24. At the same time, the suction medium 26, 32 sucks the dispersion medium contained in the fine fibrous cellulose suspension 3a on the papermaking wire 10 and squeezes it to obtain the water-containing web 3b.
If the running tension of the papermaking wire 10 is high in the water extraction process, the papermaking wire 10 may break. Therefore, the wire used for normal papermaking is placed under the papermaking wire 10 to make paper The wire 10 may be supported.

Before supplying the fine fibrous cellulose suspension 3a to the papermaking wire 10, the papermaking wire 10 may be preliminarily impregnated with water to be in a wet state. When the fine fibrous cellulose suspension 3a is discharged onto the papermaking wire 10, the wrinkle may be generated due to water absorption of the wire. However, if it is made wet in advance, the generation of the wrinkle can be prevented.
Examples of means for bringing the papermaking wire 10 into a wet state include a water tank in which the papermaking wire 10 is immersed in water and a water coating apparatus. As the water coating apparatus, a blade coater, an air knife coater, a roll coater, a bar coater, a gravure coater, a rod blade coater, a lip coater, a curtain coater, a die coater, or the like can be used.

The fine fibrous cellulose suspension 3a supplied to the papermaking wire 10 in the water squeezing step is a liquid containing fine fibrous cellulose and water.
Moreover, the fine fibrous cellulose suspension 3a may contain a resin emulsion. Here, the resin emulsion is an emulsion in which particles of natural resin or synthetic resin having a particle diameter of 0.001 to 10 μm are emulsified in water.
The particulate resin contained in the resin emulsion is not particularly limited, but polystyrene, polyvinyl chloride, polyvinylidene chloride, polyvinyl acetate, ethylene-vinyl acetate copolymer, poly (meth) acrylic acid alkyl ester polymer, ( (Meth) acrylic acid alkyl ester copolymer, resin emulsion such as poly (meth) acrylonitrile, polyester, polyurethane, natural rubber, styrene-butadiene copolymer, molecular chain terminal is —SH, —CSSH, —SO ₃ H, — (COO) _x M, — (SO ₃ ) _x M and —CO—R (wherein M is a cation, x is an integer of 1 to 3 depending on the valence of M, and R is alkyl) Styrene-butadiene copolymer modified with at least one functional group selected from the group of Modified styrene-butadiene copolymer, (meth) acrylonitrile-butadiene copolymer, polyisoprene, polychloroprene, styrene-butadiene-methyl methacrylate copolymer, styrene- (meth) acrylic Examples thereof include acid alkyl ester copolymers.
Further, polyethylene, polypropylene, polyurethane, ethylene-vinyl acetate copolymer or the like may be emulsified by a post-emulsification method.

  Furthermore, in order to improve the porosity of the obtained fine fibrous cellulose-containing sheet 3c, it is preferable to contain an organic solvent in the fine fibrous cellulose suspension 3a. When mixing the organic solvent, the mass ratio of water to the organic solvent (water: organic solvent) is preferably 100: 10 to 10: 100, more preferably 100: 30 to 30: 100, : 50 to 50: 100 is more preferable. If the mixing amount of the organic solvent is not less than the lower limit, the porosity of the fine fibrous cellulose-containing sheet 3c can be sufficiently improved, and if it is not more than the upper limit, the fine fibrous cellulose suspension 3a High viscosity can be suppressed.

  Examples of the organic solvent include glycol ethers such as dipropylene glycol methyl ether, ethylene glycol monobutyl ether, diethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethylene glycol dibutyl ether, tetraethylene glycol dimethyl ether, triethylene glycol dimethyl ether, diethylene glycol diethyl ether, and ethylene. Glymes such as glycol diethyl ether, ethylene glycol dimethyl ether, diethylene glycol isopropyl methyl ether, dihydric alcohols such as 1,2-butanediol, 1,6-hexanediol, diethylene glycol monoethyl ether acetate, ethylene glycol monomethyl ether acetate And so on. Two or more of these organic solvents may be used in combination.

  The solid content concentration of the fine fibrous cellulose suspension 3a is preferably 0.05 to 1.5% by mass, and more preferably 0.1 to 0.8% by mass. If the concentration of the fine fibrous cellulose suspension 3a is equal to or higher than the lower limit value, sufficient production efficiency can be secured in the squeezing step. Can be made.

In the water squeezing step, the finely suspended cellulose suspension 3a has a basis weight of the obtained fine fibrous cellulose-containing sheet 3c of preferably 10 to 900 g / m ² , more preferably 20 to 300 g / m ^2. Supply. When the basis weight is equal to or more than the lower limit, the obtained fine fibrous cellulose-containing sheet 3c can be easily peeled from the papermaking wire 10 and is suitable for continuous production. On the other hand, when the basis weight is not more than the above upper limit value, the dehydration time can be further shortened, and the productivity can be further increased.

(Drying process)
In the drying step, first, the coated surface A is in contact with the outer peripheral surface of the first dryer 42, with the water-containing web 3b placed on the upper surface of the papermaking wire 10 being about half the outer periphery of the heated first dryer 42. It winds and the dispersion medium which remained in the water-containing web 3b is evaporated. The evaporated dispersion medium evaporates from the felt cloth 44 through the pores of the papermaking wire 10.
Next, the water-containing web 3b is wound around about 3/4 of the outer peripheral surface of the heated second dryer 52 so that the coating surface A is in contact with the outer peripheral surface of the second dryer 52, and remains on the water-containing web 3b. Evaporate the dispersion medium.
In this manner, the water-containing web 3b is dried to obtain the fine fibrous cellulose-containing sheet 3c.

(Winding process)
In the winding process, the fine fiber cellulose-containing sheet 3c is separated from the paper making wire 10 by sandwiching the paper making wire 10 and the fine fibrous cellulose-containing sheet 3c between the pair of separation rollers 62a and 62b. Transfer to the surface of 62a. Then, the fine fibrous cellulose-containing sheet 3 c is pulled away from the surface of the separation roller 62 a and taken up by the take-up reel 64. At the same time, the used paper making wire 10 is taken up by the collection reel 66.
By using the papermaking wire 10 as described above, a fine fibrous cellulose-containing sheet can be obtained.

(Function and effect)
In the method for producing a fine fibrous cellulose-containing sheet, the fine fibrous cellulose-containing sheet 3c is produced by supplying the fine fibrous cellulose suspension 3a to the hydrophobized smooth surface of the papermaking wire 10 and making paper. It can be easily peeled off from the wire 10. Therefore, the surface quality of the obtained fine fibrous cellulose-containing sheet 3c is improved.
Furthermore, in the manufacturing method of the said fine fibrous cellulose containing sheet | seat, since the said wire 10 for papermaking is used, a fine fibrous cellulose can fully be capture | acquired and a yield becomes high.
In addition, according to the papermaking wire 10, the fine fibrous cellulose suspension 3a can always be easily filtered by the new papermaking wire 10, so that sufficient productivity can be secured.

(Other embodiments)
In addition, the manufacturing method of the fine fibrous cellulose containing sheet | seat of this invention may not be the manufacturing method using the said manufacturing apparatus 1, For example, in the said manufacturing apparatus 1, the wire 10 for papermaking is an endless or endless belt. It may be transported on top of it. Moreover, in the manufacturing method of the fine fibrous cellulose containing sheet | seat of this invention, the paper machine used when manufacturing a general paper can be applied easily. As the paper machine, in addition to a continuous paper machine such as a long-mesh type, a circular net type, and an inclined type, a multi-layered paper machine combining these can be applied.
The production of the fine fibrous cellulose-containing sheet may be performed by hand-drawing.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated more concretely, this invention is not limited to these Examples. Further, “parts” and “%” in the examples are “parts by mass” and “% by mass”, respectively, unless otherwise specified.

<Paper substrate 1>
100 parts of LBKP with 350 ml of Canadian standard freeness (hereinafter referred to as “CSF”) measured in accordance with JIS P8121 obtained by beating treatment, sizing agent (trade name: Fibran 81K, manufactured by NSC Japan) ) Paper made of 0.05 part, 0.45 part of sulfuric acid band, 0.5 part of cationized starch, 0.4 part of polyamide / epichlorohydrin resin (paper strength enhancer) and a small amount of yield improver was made on a long net. . After the wet paper thus obtained was dried, 4% starch (Ocea Cornstarch, Ace A) aqueous solution was applied on both sides by a size press method and dried so that the coating amount on one side was 0.8 g / m ² . . Thereafter, a heat calendering treatment (surface temperature: 60 ° C., liquid pressure: 100 kg / cm), surface smoothness on both sides 52 seconds, air permeability 37 seconds, paper moisture 5.5%, basis weight 64 g / m ² A paper substrate 1 was obtained. The surface smoothness and air permeability are determined by the JAPAN TAPPI paper pulp test method No. It is a value measured according to 5-2: 2000 (Oken type) (the same applies to the following paper base materials 2 and 3 and glossy paper 1 to 5).

<Paper base material 2>
100 parts of LBKP with 150 ml of CSF obtained by the beating process, 0.05 part of sizing agent (trade name: Fibran 81K, manufactured by NSC Japan), 0.45 part of sulfuric acid band, 0.5 part of cationized starch A paper stock consisting of 0.4 parts of polyamide / epichlorohydrin resin (paper strength enhancer) and a small amount of yield improver was made on a long web. After drying the wet paper thus obtained, 4% starch aqueous solution (manufactured by Oji Cornstarch Co., Ltd., Ace A) was applied on both sides by a size press method so that the coating amount on one side was 1.5 g / m ² and dried. . Thereafter, a heat calendering treatment (surface temperature: 75 ° C., linear pressure: 170 kg / cm), surface smoothness on both sides 135 seconds, air permeability 115 seconds, paper moisture 5.5%, basis weight 64 g / m ² A paper substrate 2 was obtained.

<Paper base material 3>
100 parts of LBKP with 350 ml of CSF obtained by beating treatment, 0.05 part of sizing agent (trade name: Fibran 81K, manufactured by NSC Japan), 0.45 part of sulfuric acid band, 0.5 part of cationized starch A paper stock consisting of 0.4 parts of polyamide / epichlorohydrin resin (paper strength enhancer) and a small amount of yield improver was made on a long web. After the wet paper thus obtained was dried, it was calendered (surface temperature: normal temperature, linear pressure: 50 kg / cm), surface smoothness on both sides 38 seconds, air permeability 25 seconds, paper moisture 5.5%, A paper substrate 3 having a basis weight of 64 g / m ² was obtained.

<Single glossy paper 1>
100 parts of LBKP with 100 ml of CSF obtained by beating treatment, 0.05 part of sizing agent (trade name: Fibran 81K, manufactured by Nippon SC), 0.45 part of sulfuric acid band, 0.5 part of cationized starch A paper stock consisting of 0.4 parts of polyamide / epichlorohydrin resin (paper strength enhancer) and a small amount of yield improver was made on a long web. The wet paper thus obtained was dried with a Yankee dryer, and then calendered (linear pressure: 100 kg / cm), the glossy surface was smoothed for 575 seconds, the further surface was smoothed for 7 seconds, and the air permeability was 130 seconds. Paper glossy paper 1 having a water content of 5.5% and a basis weight of 30 g / m ² was obtained.

<Glossy paper 2>
100 parts of LBKP with 180 ml of CSF obtained by beating treatment, 0.05 part of sizing agent (trade name: Fibran 81K, manufactured by NSC Japan), 0.45 part of sulfuric acid band, 0.5 part of cationized starch A paper stock consisting of 0.4 parts of polyamide / epichlorohydrin resin (paper strength enhancer) and a small amount of yield improver was made on a long web. The wet paper thus obtained was dried with a Yankee dryer, and then calendered (linear pressure: 80 kg / cm) to give a glossy surface smoothness of 630 seconds, a further surface smoothness of 8 seconds, and an air permeability of 164 seconds. to obtain a paper moisture 5.5%, a single couch paper 2 having a basis weight of 40 g / ^{m 2.}

<Glossy paper 3>
100 parts of LBKP with 330 ml of CSF obtained by beating treatment, 0.05 part of sizing agent (trade name: Fibran 81K, manufactured by Nippon SC), 0.45 part of sulfuric acid band, 0.5 part of cationized starch A paper stock consisting of 0.4 parts of polyamide / epichlorohydrin resin (paper strength enhancer) and a small amount of yield improver was made on a long web. The wet paper thus obtained is dried with a Yankee dryer and calendered (linear pressure: 50 kg / cm). The glossy surface has a surface smoothness of 192 seconds, the further surface has a surface smoothness of 7 seconds, and an air permeability of 50 seconds. Paper glossy paper 3 having a water content of 5.5% and a basis weight of 30 g / m ² was obtained.

<Glossy paper 4>
100 parts of LBKP with 220 ml of CSF obtained by beating treatment, 0.05 part of sizing agent (trade name: Fibran 81K, manufactured by Nippon CSC Co., Ltd.), 0.45 part of sulfuric acid band, 0.5 part of cationized starch A paper stock consisting of 0.4 parts of polyamide / epichlorohydrin resin (paper strength enhancer) and a small amount of yield improver was made on a long web. The wet paper thus obtained was dried with a Yankee dryer, and then calendered (linear pressure: 100 kg / cm), with a glossy surface smoothness of 385 seconds, a further surface smoothness of 8 seconds, and an air permeability of 80 seconds. Paper glossy paper 4 having a paper moisture content of 5.5% and a basis weight of 30 g / m ² was obtained.

<Single glossy paper 5>
100 parts of LBKP with 150 ml of CSF obtained by the beating process, 0.05 part of sizing agent (trade name: Fibran 81K, manufactured by NSC Japan), 0.45 part of sulfuric acid band, 0.5 part of cationized starch A paper stock consisting of 0.4 parts of polyamide / epichlorohydrin resin (paper strength enhancer) and a small amount of yield improver was made on a long web. The wet paper thus obtained was dried with a Yankee dryer, and then calendered (linear pressure: 100 kg / cm). The surface smoothness of the glossy surface was 610 seconds, the surface smoothness of the further surface was 10 seconds, and the air permeability was 138 seconds. Paper glossy paper 5 having a water content of 5.5% and a basis weight of 30 g / m ² was obtained.

(Hydrophobic agent paint 1)
100 parts of silicone-based hydrophobizing agent KS3600 (manufactured by Shin-Etsu Chemical Co., Ltd.) and 1 part of curing agent PL50T (manufactured by Shin-Etsu Chemical Co., Ltd.) so as to have a concentration of 3% in a mixed solvent of toluene / ethyl acetate 3/1 The resultant was added and stirred to obtain a hydrophobizing agent paint 1.

(Hydrophobic agent paint 2)
Hydrophobizing agent Pyroyl HT (manufactured by Yushi Kogyo Co., Ltd.) made of alkyd resin was added to a mixed solvent of toluene / ethyl acetate 3/1 to a concentration of 3%, stirred, and hydrophobized paint 2 Got.

(Hydrophobic agent paint 3)
Hydrophobizing agent Hydrin P-7 (manufactured by Chukyo Yushi Co., Ltd., paraffin wax) was added to water to a concentration of 3% and stirred to obtain hydrophobizing agent paint 3.

(Hydrophobic agent paint 4)
Hydrophobizing agent Hydrin Z-7-30 (manufactured by Chukyo Yushi Co., Ltd., zinc stearate) was added to water to a concentration of 3% and stirred to obtain hydrophobizing agent paint 4.

(Hydrophobic agent paint 5)
Hydrophobizing agent Hydrin L-271 (manufactured by Chukyo Yushi Co., Ltd., stearamide) was added to water to a concentration of 3% and stirred to obtain hydrophobizing agent paint 5.

(Hydrophobic agent paint 6)
Hydrophobizing agent Asahi Guard AG060 (manufactured by Asahi Glass Co., Ltd., fluorine-based compound) was added to water to a concentration of 3% and stirred to obtain hydrophobizing agent paint 6.

Example 1
Fine fiber with hydrophobizing agent paint 1 applied to one side of paper substrate 1 with a bar coater so that the coating amount is 2 g / m ² and dried at 120 ° C. to make one side hydrophobic and smooth. A cellulose-containing sheet paper making wire was obtained.

(Example 2)
Fine fiber with hydrophobizing agent paint 1 applied to one side of paper substrate 2 with a bar coater so that the coating amount is 2 g / m ² and dried at 120 ° C. to make one side hydrophobic and smooth. A cellulose-containing sheet paper making wire was obtained.

(Example 3)
The glossy surface of the glossy paper 1 was coated with the hydrophobizing agent paint 1 with a bar coater so that the coating amount was 2 g / m ² , and dried at 100 ° C. to make the glossy surface hydrophobic and smooth. A fine fibrous cellulose-containing sheet paper making wire was obtained.

Example 4
The glossy surface of the glossy paper 2 was coated with the hydrophobizing agent paint 1 with a bar coater so that the coating amount was 2 g / m ² and dried at 100 ° C. to make the glossy surface hydrophobic and smooth. A fine fibrous cellulose-containing sheet paper making wire was obtained.

(Example 5)
The glossy surface of the single glossy paper 3 was coated with the hydrophobizing agent paint 1 with a bar coater so that the coating amount was 2 g / m ² and dried at 100 ° C. to make the glossy surface hydrophobic and smooth. A fine fibrous cellulose-containing sheet paper making wire was obtained.

(Example 6)
The glossy surface of the single glossy paper 4 was coated with the hydrophobizing agent paint 1 with a bar coater so that the coating amount was 2 g / m ² and dried at 100 ° C. to make the glossy surface hydrophobic and smooth. A fine fibrous cellulose-containing sheet paper making wire was obtained.

(Example 7)
The glossy surface of the glossy paper 5 was coated with the hydrophobizing agent paint 1 with a bar coater so that the coating amount was 2 g / m ² , and dried at 100 ° C. to make the glossy surface hydrophobic and smooth. A fine fibrous cellulose-containing sheet paper making wire was obtained.

(Example 8)
The glossy surface of the glossy paper 1 was coated with a hydrophobizing agent paint 2 with a bar coater so that the coating amount was 2 g / m ² and dried at 100 ° C. to make the glossy surface a hydrophobic smooth surface. A fine fibrous cellulose-containing sheet paper making wire was obtained.

Example 9
The glossy surface of the glossy paper 1 was coated with a hydrophobizing agent paint 3 with a bar coater so that the coating amount was 2 g / m ² and dried at 100 ° C. to make the glossy surface hydrophobic and smooth. A fine fibrous cellulose-containing sheet paper making wire was obtained.

(Example 10)
The glossy surface of the glossy paper 1 was coated with a hydrophobizing agent coating 4 with a bar coater so that the coating amount was 2 g / m ² and dried at 100 ° C. to make the glossy surface hydrophobic and smooth. A fine fibrous cellulose-containing sheet paper making wire was obtained.

(Example 11)
The glossy surface of the single glossy paper 1 was coated with the hydrophobizing agent paint 5 with a bar coater so that the coating amount was 2 g / m ² and dried at 100 ° C. to make the glossy surface hydrophobic and smooth. A fine fibrous cellulose-containing sheet paper making wire was obtained.

(Example 12)
The glossy surface of the glossy paper 1 was coated with a hydrophobizing agent paint 6 with a bar coater so that the coating amount was 2 g / m ² and dried at 100 ° C. to make the glossy surface hydrophobic and smooth. A fine fibrous cellulose-containing sheet paper making wire was obtained.

(Comparative Example 1)
Fine fiber with hydrophobizing agent paint 1 applied to one side of paper substrate 3 with a bar coater so that the coating amount is 2 g / m ² and dried at 120 ° C. to make one side hydrophobic and smooth. A cellulose-containing sheet paper making wire was obtained.

(Comparative Example 2)
The single glossy paper 1 was used as a fine fiber cellulose-containing sheet paper making wire.

(Comparative Example 3)
The single glossy paper 2 was a fine fibrous cellulose-containing sheet paper making wire.

(Comparative Example 4)
The single glossy paper 3 was used as a fine fiber cellulose-containing sheet paper making wire.

(Comparative Example 5)
The single glossy paper 4 was a fine fiber cellulose-containing sheet paper making wire.

(Comparative Example 6)
The single glossy paper 5 was a fine fibrous cellulose-containing sheet paper making wire.

(Comparative Example 7)
Applying hydrophobizing agent paint 2 to the further surface of single glossy paper 1 with a bar coater so that the coating amount is 2 g / m ² and drying at 100 ° C. to make the further surface hydrophobic. A cellulose-containing sheet paper making wire was obtained.

(Comparative Example 8)
The surface of the glossy paper 1 is coated with a hydrophobizing agent paint 3 with a bar coater so that the coating amount is 2 g / m ² and dried at 100 ° C. to make the further surface hydrophobic. A cellulose-containing sheet paper making wire was obtained.

(Comparative Example 9)
The surface of the glossy paper 1 is coated with a hydrophobizing agent coating 4 with a bar coater so that the coating amount is 2 g / m ² and dried at 100 ° C. to make the further surface hydrophobic. A cellulose-containing sheet paper making wire was obtained.

(Comparative Example 10)
The surface of the glossy paper 1 is coated with a hydrophobizing agent coating 5 with a bar coater so that the coating amount is 2 g / m ² and dried at 100 ° C. to make the further surface hydrophobic. A cellulose-containing sheet paper making wire was obtained.

(Comparative Example 11)
The surface of the glossy paper 1 is coated with a hydrophobizing agent coating 6 with a bar coater so that the coating amount is 2 g / m ² and dried at 100 ° C. to make the further surface hydrophobic. A cellulose-containing sheet paper making wire was obtained.

<Evaluation of papermaking wire>
The surface smoothness and air permeability of the surface on the hydrophobic side of the wire of each example and each comparative example were measured according to JAPAN TAPPI paper pulp test method No. It was measured according to 5-2: 2000 (Oken type). The measurement results are shown in Table 1.

<Production of fine fibrous cellulose-containing sheet>
(Fine fibrous cellulose suspension)
Fine fibrous cellulose (manufactured by Daicel Chemical Industries, trade name: Celish KY-100G, solid content concentration 10%) with a fiber width reduced to 10 to 100 nm in water so that the cellulose concentration becomes 0.1%. And redispersed to obtain a slurry. The slurry was uniformly dispersed for 10 minutes, and then a cationic polyurethane resin emulsion having a solid content concentration of 0.5% (Daiichi Kogyo Seiyaku Co., Ltd., trade name: Superflex 650) was added. At that time, the cellulose solid content was 70 parts and the cationic polyurethane resin solid content was 30 parts. Thereby, a fine fibrous cellulose suspension containing fine fibrous cellulose and a cationic polyurethane resin was obtained.

(Filtration of fine fibrous cellulose suspension)
The papermaking wire was placed on a Buchner funnel type glass filter (KG-90 manufactured by Advantech Co., Ltd.) having a sintered size of 30 to 50 μm. At that time, the papermaking wires of Examples 1 to 12 and Comparative Examples 1 and 7 to 11 are arranged so that the hydrophobic surface faces upward, and the papermaking wires of Comparative Examples 2 to 6 have a glossy surface. Arranged to face up.
Next, after the glass filter on which the papermaking wire was placed was placed on the filter bottle, the fine fibrous cellulose suspension was prepared such that the basis weight of the fine fibrous cellulose-containing sheet was adjusted to 30 g / m ^2. The liquid was cast on the papermaking wire on the filter under conditions of atmospheric pressure and temperature of 23 ° C. At that time, the filter bottle was sucked with an aspirator so that the suction pressure was 0.08 MPa or more and filtered. At this time, the filtration time was measured. The results are shown in Table 1.
Thereafter, the wet fine fibrous cellulose-containing sheet and the wire were peeled from the glass filter, dried with a cylinder dryer, and then peeled from the papermaking wire to obtain a fine fibrous cellulose-containing sheet.

  The yield, peelability, and surface quality of the fine fibrous cellulose-containing sheet were evaluated as follows. The evaluation results are shown in Table 1.

[Yield evaluation]
The yield during the production of the fine fibrous cellulose-containing sheet was determined from the following formula.
Yield (%) = 100 × (C−B) / A
A: Mass of fine fibrous cellulose contained in suspension B: Mass of papermaking wire C: Total mass of papermaking wire and fine fibrous cellulose-containing sheet

[Peelability evaluation]
The peelability between the dried fine fibrous cellulose-containing sheet and the papermaking wire was visually evaluated.
(Double-circle): When peeling the fine fibrous cellulose containing sheet | seat from the wire for papermaking, the fluff of the fine fibrous cellulose was not seen, but it was able to peel favorably without remaining on a wire.
○: When the fine fibrous cellulose-containing sheet was peeled from the papermaking wire, fluffing of the fine fibrous cellulose was observed, but the fine fibrous cellulose did not remain on the wire and could be peeled well.
Δ: When the fine fibrous cellulose-containing sheet is peeled from the papermaking wire, the fluff of the fine fibrous cellulose is noticeable and the fine fibrous cellulose remains slightly on the wire, but there is no practical problem.
X: When the fine fibrous cellulose-containing sheet is peeled from the papermaking wire, the fine fibrous cellulose has a lot of fluffing and remains on the wire, and the fine fibrous cellulose-containing sheet is broken.

[Surface quality of fine fibrous cellulose-containing sheet]
The surface quality of the obtained fine fibrous cellulose-containing sheet was visually evaluated.
A: Surface quality is extremely good.
○: Slight fiber fluffing is observed, but surface quality is good.
(Triangle | delta): The fuzz of a fiber is conspicuous and surface quality is a little bad.
X: Surface quality is poor.

[result]
As is apparent from Table 1, when the papermaking wire obtained in each example was used, the resulting fine fibrous cellulose-containing sheet was excellent in peelability and surface quality. In addition, the yield and filtration speed were also ensured.
In contrast, one side of the paper base material was hydrophobized, but in the paper making wire of Comparative Example 1 whose surface smoothness was less than 50 seconds, a fine fibrous cellulose-containing sheet was formed on the hydrophobized surface. Even so, the peelability and surface quality of the fine fibrous cellulose-containing sheet were both low.
In the papermaking wires of Comparative Examples 2 to 6 made of single glossy paper and the glossy surface is not hydrophobized, even if a fine fibrous cellulose-containing sheet is formed on the glossy surface, the peelability of the fine fibrous cellulose-containing sheet Both surface quality was low.
In the papermaking wires of Comparative Examples 7 to 11 in which the further surface of the glossy paper was hydrophobized and the surface smoothness was less than 50 seconds, the fine fiber cellulose-containing sheet was formed on the hydrophobized surface, but the fine fibers Both the peelability and surface quality of the cellulose-containing sheet were low.

In addition, from the results of the above examples, in Examples 3 to 12 in which the glossy surface of the glossy paper was hydrophobized to be a hydrophobized smooth surface, Examples 1 and 2 in which one side of the paper substrate was hydrophobized smooth surface and In comparison, the surface quality of the fine fibrous cellulose-containing sheet was more excellent.
Furthermore, in Examples 3 to 7 in which a silicone compound was applied to the glossy surface of single glossy paper to make it a hydrophobic smooth surface, the peelability of the fine fibrous cellulose-containing sheet was particularly excellent.

1 Production Equipment 3a Fine Fibrous Cellulose Suspension 3b Hydrous Web 3c Fine Fibrous Cellulose-Containing Sheet 10 Papermaking Wire 20 Squeezing Section 40 Drying Section 60 Winding Section

Claims (5)

At least one surface of the paper substrate, Ri Do from sheet hydrophobized and surface smoothness by hydrophobizing agent is a hydrophobic smooth surface more than 50 seconds, the fine cellulose-containing sheet in said hydrophobic smooth surface the microfibrous cellulose-containing sheet papermaking wires, characterized in papermaking to Rukoto.
  The wire for fine fiber cellulose-containing sheet papermaking according to claim 1, wherein the hydrophobic smooth surface has a surface smoothness of 200 to 800 seconds.   The fine fibrous cellulose-containing sheet according to claim 1 or 2, wherein the paper base material is a single glossy paper having a glossy surface on one side, and the glossy surface is hydrophobized to be a hydrophobized smooth surface. Paper making wire.   The hydrophobizing agent is at least one selected from the group consisting of a silicone compound, a fluorine compound, a polyolefin wax, a higher fatty acid amide, a higher fatty acid alkali salt, and an acrylic polymer. Wire for making sheet of fine fibrous cellulose. A fine fibrous cellulose-containing sheet having a water extraction step of filtering and dewatering a suspension containing fine fibrous cellulose and water using a papermaking wire to obtain a water-containing web, and a drying step of drying the water-containing web A method of manufacturing
In the squeezing step, the fine fibrous cellulose-containing sheet paper making wire according to any one of claims 1 to 4 is used as the paper making wire, and the suspension is used as the fine fibrous cellulose-containing sheet paper making wire. A method for producing a fine fibrous cellulose-containing sheet, characterized in that it is supplied to a hydrophobized smooth surface.

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