JP2000336591A - Sheet carrying activated charcoal and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet-like material which can effectively exhibit the excellent functions of charcoal. SOLUTION: This activated charcoal-carrying sheet is obtained by making the sheet from a fibrous material and activated charcoal. Therein, the sheet comprises 30 to 85 wt.% of the fibrous material as a basic material, 3 to 50 wt.% of the powder of the activated charcoal prepared by carbonizing wood chips, and 5 to 30 wt.% of fibrillated acrylic fibers.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to humidity control of charcoal,
Activated charcoal-carrying sheet, which is a sheet-like article that can effectively use functions such as deodorization and far-infrared radiation,
The present invention relates to a method for producing the activated charcoal-carrying sheet.

[0002]

2. Description of the Related Art Charcoal has a function of absorbing excessive moisture in the environment and gradually releasing the absorbed moisture into the environment, and the humidity of the environment becomes too high or too dry. It is known that there is a humidity control function to prevent this. In addition, a deodorizing function of adsorbing odors in the environment and a function of emitting far-infrared rays to keep the human body warm and promote health are also known.

In order to incorporate the charcoal having such excellent functions into various products for easy use, a charcoal powder is kneaded in a synthetic resin, or a charcoal powder in which a charcoal powder is dispersed in a resin solution. Has been proposed to be applied to the surface of various products. It has also been proposed that, when paper is made, charcoal powder is dispersed in a papermaking liquid, and the pulp fibers constituting the paper carry the charcoal powder at the same time as papermaking.

[0004] If the above-mentioned function of charcoal can be imparted to paper or a synthetic resin sheet, it can be easily used for various household articles, housing materials, building materials, and the like, resulting in high commercial value.

[0005]

Among the above-mentioned techniques for utilizing charcoal, in the technique of blending charcoal powder into a resin, the surface of the charcoal powder is coated with the resin. And the deodorizing function is impaired. The various functions of charcoal are that the charcoal has a porous structure consisting of minute voids, and that it is exerted by the catalytic action and activation action on the surface inside the voids of this porous structure. If it is covered with a resin or the like, the porous structure is closed, and the intended function cannot be exhibited effectively.

[0006] In the technique of blending charcoal powder during papermaking, the charcoal powder falls off during handling or use of the charcoal-bearing paper because the charcoal powder does not adhere sufficiently to the paper fibers. There is a problem that the intended function cannot be exhibited. Workers and the environment handling the charcoal-carrying paper become dirty with charcoal powder that has fallen off the paper. In order to firmly adhere the charcoal powder to the paper, it has been proposed to mix various coagulants and adhesives. However, when these chemicals coat the surface of the charcoal powder, the resin described above is used. As in the case where the charcoal powder is blended into the powder, there is a problem that the function of the charcoal powder cannot be sufficiently exhibited.

An object of the present invention is to solve the above-mentioned problems of the prior art and to provide a sheet-like material capable of effectively exhibiting the excellent functions of charcoal.

[0008]

The activated charcoal-carrying sheet according to the present invention is a sheet obtained by paper-making a fiber material. Activated charcoal powder obtained by carbonization is 3-50
5% by weight and 5-30% by weight of fibrillated acrylic fiber
And [Fiber material as base material] A fiber material for producing a fibrous sheet material such as ordinary paper or nonwoven fabric is used.

Specifically, wood pulp, hemp, cotton, bamboo,
Straw, polyester, vinylon, nylon, acrylic, rayon, polypropylene, polyethylene, and the like. If fusible binder fibers such as polyester, vinylon, nylon, polypropylene, and polyethylene are blended as the fiber material, the integrity of the fibers and the adhesion of the activated charcoal powder to the fibers are improved.

The use of fibers having an irregular cross section as the fiber material is effective in reducing the density of the sheet and improving the air permeability. By blending a material having low adhesiveness to the heat-fusible binder fiber, it is easy to secure a ventilation space. If an antibacterial fiber and / or an antifungal fiber is contained as a fiber material, propagation of various bacteria and fungi attached to the fiber material and activated charcoal can be suppressed. [Activated charcoal] A material in which various functions of charcoal are improved by carbonizing and activating wood chips. By appropriately setting the raw materials, carbonization conditions, activation treatment conditions, and the like, a high-performance charcoal can be obtained.

As the activated charcoal, the technique described in Japanese Patent Application No. 11-26719, which has been completed by a part of the present applicant and filed for a patent, can be applied. Specifically, softwood such as red pine is used as a raw material for charcoal, and the wood is finely chopped and used in the form of wood chips having a maximum diameter of about 10 to 60 mm. A low-temperature carbonization step of heat-treating such wood chips at 450 to 550 ° C. and a low-temperature carbonization step.
A high-temperature carbonization step in which heat treatment is performed for 80 to 960 seconds to further carbonize, and an activation step of bringing water into contact with the carbide at the end of the high-temperature carbonization step are performed.

The activated charcoal obtained by the above method has a porous structure having a large number of micropores therein, and exhibits high adsorption performance by physical and chemical actions. In particular, when the low-temperature carbonized portion and the high-temperature carbonized portion coexist, the excellent functions of both are synergistically exerted, and have a practically high function. Activated charcoal is used as fine powder.
As the pulverizing means, a pulverizing device and pulverizing conditions for ordinary charcoal and the like can be applied. Those having an average particle diameter of 5 to 100 μm are preferred.

The activated charcoal preferably has the following functions. High adsorption capacity. The function of absorbing and releasing moisture, deodorizing, removing harmful volatile components such as formaldehyde and ammonia.
A function to decompose and detoxify the adsorbed harmful substances. Antifungal, far-infrared radiation, conductivity, electromagnetic wave absorption, ion adjustment function. The amount of the activated charcoal is 3 to 50% by weight based on the total amount of the raw material of the activated charcoal-carrying sheet. 3
When the content is set to ２０20% by weight, the inhibition of inter-fiber bonding by charcoal is reduced, which is preferable from the viewpoint of the practical strength of paper. [Fibrillated acrylic fiber] An acrylic fiber fibrillated by ordinary fibrillation means or beating means. Fibrillated acrylic fibers have a structure in which fibers are finely branched.

As a fibrillated fiber, Japanese Patent Application No. 10-2427, which has been completed and filed by a part of the present applicant, has been filed.
The technology described in No. 35 can be applied. In the above technique, the acrylonitrile content is 80% by weight or more and the difference is 5%.
An acrylic fiber manufactured from two or more acrylonitrile-based polymers in an amount of at least 130% by weight.
The fibrillated fiber is 300% by weight, and the fibrillated fiber is obtained by fibrillating the fibrillated fiber. By subjecting a multilayer structure composed of two types of materials to fibrillation treatment while maintaining an appropriate internal moisture content, a finely branched structure can be easily obtained. Activated charcoal can be supported with this finely branched structure sandwiched therebetween. In addition, the fibrillated acrylic fiber has self-adhesive properties, and can firmly join the activated charcoal carried.

[0015] In addition to acrylonitrile, a polymer for producing an acrylic fiber may contain, in addition to alkyl acrylate, acrylic acid, acrylamide, vinyl chloride, styrene and other comonomers. Canadian Standard Freeness (CS
F) Preferably beaten to 100-500 ml. [Production of activated charcoal-carrying sheet] Basically, papermaking means common to production of ordinary paper or nonwoven fabric is employed.

The fibrous material, activated charcoal powder and fibrillated acrylic fiber as the base material are dispersed in water. In addition to the above-mentioned materials, various kinds of additive materials added during ordinary papermaking can be added to this dispersion. However, it is preferable not to mix a material that inhibits the function of activated charcoal. If the dispersion is used to make paper by ordinary papermaking means, an activated charcoal-carrying sheet is obtained.

Activated charcoal is efficiently captured by the fibrillated acrylic fibers having the finely branched structure described above. Moreover, the fibrillated acrylic fiber exhibits self-adhesiveness in a drying step after papermaking, and can carry activated charcoal in a strongly bonded state. At the time of the above-mentioned papermaking, if a layer of a fiber material not containing activated charcoal is laminated on a layer of fiber material containing activated charcoal, activated charcoal non-supported on one or both sides of the activated charcoal supporting layer. An activated charcoal-carrying sheet in which the layers are stacked can be obtained. A plurality of layers in which activated charcoal is blended but the composition of the fiber material is different can be laminated.

The activated charcoal-carrying sheet thus produced is subjected to ordinary dehydration, drying and other finishing steps to become a product of the activated charcoal-carrying sheet. If the obtained activated charcoal-carrying sheet has an air permeability of 0.05 to 3.0 sec / 100 ml, the function of the activated charcoal supported can be sufficiently exhibited. Also,
When the thickness of the sheet is 100 to 300 μm, 0.0
A more preferable range is 5 to 0.50 sec / 100 ml. By having an appropriate air permeability, moisture and harmful gases in the environment can smoothly enter the inside of the activated charcoal-carrying sheet, and the activated charcoal adsorption function and the like can be sufficiently exhibited.

A laminated sheet can also be produced by laminating another sheet of paper, nonwoven fabric or other film or sheet material on the activated charcoal-carrying sheet. When activated charcoal is carried, a black sheet, which is the color of charcoal, is obtained. If a surface color other than black is preferable, a non-colored or paper layer having a color other than black may be laminated. [Use of activated charcoal-carrying sheet] It can be used for the same purpose as a charcoal-carrying sheet that has conventionally supported or blended charcoal. Since the function of the charcoal can be more effectively exhibited, and the charcoal is less likely to fall off, the charcoal can be used for new uses that could not be used with the conventional charcoal-carrying sheet.

Specific examples of applications include agricultural and horticultural sheets, mats, and heat-insulating sheets because of their excellent far-infrared radiation characteristics. It can be used for building interior materials. It becomes a deodorant sheet. There are freshness holding sheets for vegetables and flowers. It can be used as antistatic material. Becomes an electromagnetic wave shielding material.

[0021]

〔material〕

 Wood pulp: Softwood bleached kraft pulp Activated charcoal: "C-10WP" manufactured by Hinomaru Carbo Techno Co., Ltd. Average particle size 10 μm.

Antibacterial acrylic fiber: "NX-85" manufactured by Exlan Japan, 1.5 denier, 5 mm cut product. Fibrillated acrylic fiber: "R56F" (easy fibrillated acrylic fiber) manufactured by Exlan Japan Co., Ltd. was adjusted to a beating degree of 380 ml CSF. Polyester fiber: Kuraray “EPTC 203 ×
5 "PVA binder fiber:" VPB 107-1 "manufactured by Kuraray Co., Ltd.
× 3 ”[Papermaking] Papermaking equipment: Short net Yankee papermaking machine Papermaking method: One-layer netting [Measurement conditions] Papermaking adequacy: Evaluate the status of papermaking work by papermaking properties, and coloration of wastewater generated during papermaking Was evaluated for drainage pollution.

Physical property items: JIS-P8124 for basis weight, JIS-P8118 for thickness and density, JIS-P8118 for air permeability
P8117 and tensile strength were measured according to JIS-P8113, respectively. The amount of charcoal supported was measured by the following method.

After the sample sheet was completely dried, it was weighed (weight W ₀ ). Next, it was immersed in dimethylformamide (DMF), stirred at 70 ° C. for 60 minutes, and washed with DMF. Next, the mixture was stirred in a 30% aqueous sodium hydroxide solution at 100 ° C. for 2 hours, and then washed with water. Next, after heating in a 60% nitric acid solution for 2 hours, the mixture was neutralized with 30% caustic soda, decantation and water washing were repeated three times, the precipitate was completely dried, and its weight was measured (weight W ₁ ). The amount of charcoal supported was calculated from W ₀ and W ₁ by the following equation (1).

Amount of charcoal supported (% by weight) = W ₁ / W ₀ × 100 (1) Function item: The moisture absorption / release properties were measured according to JIS-L1096. The difference (H ₂ −H) between the moisture absorption (H ₁ ) after standing at 23 ° C. and 50% RH for 4 hours and the moisture absorption (H ₂ ) after standing at 23 ° C. and 90% RH for 4 hours. ₁ ) is displayed in%.

The gas adsorption removal property was measured by the following method. A 10 × 10 cm sample sheet is sealed in a TEDLAR pack (30 liters). A predetermined amount of a gas source having a predetermined concentration was taken in a gas chromatography preparative collection trap. The nitrogen cylinder, the trap, and the TEDLAR pack were connected by a rubber tube, heated with hot water while flowing nitrogen, and volatile gas components generated from a gas generation source were supplied to the pack and sealed. One hour later, the residual gas concentration (C ₁ ) of the gas-filled pack was measured using a gas-tech detector tube. From the previously measured initial concentration (C ₀ ), the gas adsorption removal rate was calculated by the following equation (2). Note that the initial concentration C ₀ differs depending on the gas, formaldehyde is 3 ppm,
Ammonia was 50 ppm, acetic acid was 20 ppm, and isovaleric acid was 25 ppm.

Gas adsorption removal rate (%) = (C ₀ −C ₂ ) / C ₁ × 100 (2) Antibacterial activity is measured using Staphylococcus aureus, and a unified test method manual of the Evaluation Committee for New Functions of Textile Products It measured according to.

[0028]

[Table 1] 例 Example Comparative example ───────── ──────────────────────── <Material composition> Wood pulp 45 55 Activated charcoal 20 20 Antibacterial acrylic fiber 10 10 Fibrillated acrylic fiber 100 Polyester fiber 10 10 PVA binder fiber 55 5 <Appropriate papermaking> Good papermaking Net contamination is not possible. Wastewater pollution Light gray Dark black ────────────────────────────────── <Physical properties> Basis weight g / m ² 51.0 51.5 Thickness μm 172 174 Density g / cm ³ 0.297 0.296 Air permeability sec / 100 ml 0.18 0.18 Tensile strength kg / 15mm (MD / CD) 2.72 / 1 .68 2.62 / 1.82 Charcoal supported weight% 19.7 4.8 ──── <Functional items> Moisture absorption / release properties% 5.0 1.8 Gas adsorption removal properties% Formaldehyde 73.3 23.1 Ammonia 84.5 35.3 Acetic acid 89.0 48.5 Isovaleric acid 76.8 27.0 Antibacterial% 4.8 4.8

As a result of the above evaluation test, in the examples of the present invention, the use of the fibrillated acrylic fiber in addition to the composition of the comparative example allows the activated sheet charcoal to be favorably carried on the sheet formed. It was demonstrated that continuous papermaking was possible and productivity was significantly improved. In the example, the difference between the amount of blended charcoal and the amount of supported charcoal is small, and the dropped charcoal does not pollute the wastewater. The functions of activated charcoal, such as moisture absorption and desorption properties and gas adsorption and removal properties, are effectively exhibited.

Further, in the embodiment, the irregular cross section is made of PVA.
It was confirmed that by containing a polyester fiber having low adhesiveness to the fiber, the density of the sheet was reduced and the air permeability was improved. By containing antibacterial acrylic fiber, antibacterial property was improved.

[0031]

The activated charcoal-carrying sheet and the method for producing the same according to the present invention are useful for producing an activated charcoal-carrying sheet by producing activated charcoal powder having excellent adsorption function and the like together with a fiber material. By blending the activated acrylic fiber, the activated charcoal powder can be reliably and firmly supported.
During the manufacturing process and after handling and use,
The activated charcoal does not fall off and the function is not reduced, and the surroundings are not stained with charcoal.

In addition, the activated charcoal powder carried by the fibrillated acrylic fiber does not block the surface of the charcoal, and makes good contact with the external environmental atmosphere. The function can be fully demonstrated.

 ──────────────────────────────────────────────────続 き Continuing from the front page (71) Applicant 393002726 Morza Co., Ltd. 983, Hachiman, Mugegawa-cho, Mugi-gun, Gifu-ken (72) Inventor Yoshitaka Kawajiri 17-7 Kaminonomecho, Minami-ku, Hiroshima-shi (72) Inventor Ishimaru Exhibition Hisa, No. 8 1-114 Minamieganoso, Habikino-shi, Osaka (72) Inventor Hideo Naka Inventor 794-14 Kanada, Okayama-shi, Okayama Prefecture (72) Inventor Takayuki Goto 983 Yawata 983, Mugegawa-cho, Mugi-gun, Gifu-pref. F term (reference) 4G066 AA04B AC02C AC13C AC16C AC17C AC23C AC26C BA03 BA09 BA16 BA20 BA35 BA38 CA29 CA52 CA56 DA03 FA37 FA40 4L055 AA01 AA05 AA07 AA08 AF09 AF10 AF16 AF17 AF21 AF29 AF33 AF35 EA EA EA96 EA16 EA32 FA11 GA03 GA21 GA25 GA50

Claims (9)

[Claims] 1. A sheet obtained by paper-making a fiber material, wherein the fiber material as a base material is 30 to 85% by weight, and the activated charcoal powder obtained by carbonizing wood chips is 3 to 5%.
An activated charcoal-carrying sheet containing 0% by weight and 5 to 30% by weight of fibrillated acrylic fibers. 2. The activated charcoal powder has an average particle size of 5 to 5.
The activated charcoal-carrying sheet according to claim 1, which is 100 µm. 3. The fibrillated acrylic fiber has an internal moisture content of 130 to 300% in the fiber.
The activated charcoal-carrying sheet according to claim 1 or 2, which is beaten to 0 to 500 ml. 4. The fiber material serving as the base material is wood pulp,
Hemp, cotton, bamboo, straw, polyester, vinylon, nylon,
The activated charcoal-carrying sheet according to any one of claims 1 to 3, wherein the sheet mainly comprises any one kind of fiber selected from the group consisting of acrylic, rayon, polypropylene, and polyethylene. 5. The fiber material serving as the base material contains any one kind of fusible binder fiber selected from the group consisting of polyester, vinylon, nylon, polypropylene, and polyethylene. The activated charcoal-carrying sheet according to 1. 6. The activated charcoal-carrying sheet according to claim 1, wherein the fiber material serving as the base material contains antibacterial fibers and / or antifungal fibers. 7. The activated charcoal-carrying sheet according to claim 1, which has an air permeability of 0.05 to 1.0 sec / 100 ml. 8. An activated charcoal-supporting layer comprising the activated charcoal-supporting sheet according to any one of claims 1 to 7, and arranged on one or both sides of the activated charcoal-supporting layer and containing no activated charcoal. An activated charcoal-carrying sheet comprising a layer made of a fiber material. 9. The method for producing an activated charcoal-carrying sheet according to claim 1, wherein the fibrous material, activated charcoal powder, and fibrillated acrylic fibers are used as water. A method for producing an activated charcoal-carrying sheet, comprising the steps of: (a) dispersing the activated carbon charcoal into a sheet;