JPH073036A - Functional material and manufacturing method thereof - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a functional material in which the functional powder is fixed so that the function of the functional powder is not impaired and is not easily removed, and a method for producing the same. [Structure] A functional powder is fixed to a porous body by a mixture of a binder and microfibril cellulose.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a functional material containing a functional powder such as a deodorant and a catalyst, and a method for producing the functional material.
More specifically, the present invention relates to a functional material in which the functional powder is fixed so that the function of the functional powder is not impaired and is not easily removed, and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, the problems to be solved by the invention
There is known a functional material in which a powder having a specific function such as a deodorizing function, an ozone decomposing function, a catalyst function, and a filtering function is attached to a porous body such as a non-woven fabric, a cloth or a foam. By adhering the functional powder to a porous body having a large surface area, these functional materials can maximize the function of the functional powder with respect to a substance that passes through or comes into contact with the porous body. The purpose is to make it available to the limit.
For example, if a powder having a function of decomposing ozone such as manganese dioxide is attached to a porous body such as a nonwoven fabric, ozone contained in a gas passing through the nonwoven fabric can be efficiently decomposed by manganese dioxide.

Conventionally, as a method for producing a functional material by attaching the functional powder to the porous body, a method of attaching the functional powder to the porous body via a binder or an adhesive fiber is known. ing. In the method of attaching the functional powder to the porous body with the binder, a method of dispersing the powder in the binder and impregnating or coating the porous body with the binder is used. For this reason, the surface of the functional powder may be covered with the binder to deteriorate the function.

On the other hand, when the adhesive fiber is used, most of the functional powder can be used because the powder and the adhesive fiber contact and adhere at one point, but a large amount of the powder is adhered. It is difficult to do so, and the powder tends to fall off. Furthermore, since the powder can be attached only to the surface of the adhesive fiber, the porous body itself used is limited to those capable of using a large amount of fiber. There was also a problem that it could not be used.

The present invention has been made in view of such problems, and in order not to impair the function of the functional powder,
Moreover, it is an object of the present invention to provide a functional material in which the functional powder is fixed so as not to fall off easily and a method for producing the functional material.

[0006]

In order to achieve the above object, in the invention according to claim 1, a porous body is made to function by a mixture of a binder and microfibril cellulose (hereinafter referred to as MFC). The gist is a functional material characterized in that the functional powder is fixed.

The invention according to claim 2 is a binder and MF
The functional material is characterized in that the functional powder is fixed to the porous body by a mixture of C and polytetrafluoroethylene (hereinafter referred to as PTFE).

The invention according to claim 3 is the PTF in the mixed solution.
The gist is a functional material characterized in that E is fibrillated.

A fourth aspect of the present invention has as its gist a method for producing a functional material, which comprises applying a mixed liquid containing a functional powder, a binder and MFC to a porous body and drying the mixture. .

A fifth aspect of the present invention provides a method for producing a functional material, which comprises applying a mixed solution containing a functional powder, a binder, MFC and PTFE to a porous body and drying the mixture. And

The invention according to claim 6 is the PTF in the mixed solution.
The gist is a method for producing a functional material characterized by fibrillating E.

The functional material of the present invention and the method for producing the same will be described below in detail. First, the functional material according to claim 1 will be described. This functional material is obtained by fixing the functional powder on a porous body with a mixture of a binder and MFC. As a functional powder, adsorption,
Powders having functions such as deodorization and decomposition are used. For example, metal oxides such as "manganese dioxide", "titanium dioxide", "silicon dioxide", and "zirconium dioxide" used in ozone decomposition sheets and their complex oxidation. "Activated carbon" used for deodorizing sheets to deodorize the odor of ammonia, "zeolite", "Ceragit", "sepiolite", "activated carbon" used for removing sheets to remove tobacco odor, sulfur oxides and nitrogen oxides, thiols , "Zeolite" used for removal sheet to remove hydrogen sulfide,
"Sepiolite", which is used as a freshness-keeping sheet that removes ethylene gas generated from vegetables, "Zeolite", "potassium titanate" that is used as a filter sheet for sake, "Sepiolite" that is used as a liquid adsorption filter sheet in soy sauce Alternatively, there may be mentioned an ion exchange resin and a resin powder of a resin having an ability to adsorb microorganisms.

As the porous body, any of those conventionally known as porous materials can be used. The material, density, size, shape, number of pores, size of pores, etc. of the porous body are The functional material can be appropriately selected and used according to the application. For example, non-woven fabrics, woven fabrics, knitted fabrics, porous plastic films, and foams are generally known as porous materials. In addition, as a porous body manufactured for use in a special purpose, a particle shape-adjusted granular material such as glass beads is point-bonded and molded into a predetermined shape, its carbide, or a plant or animal tissue is used as it is. However, there is also a carbonized version of this. In particular, since the non-woven fabric has a large surface area and low resistance when the liquid to be treated passes, it is possible to efficiently use the function of the functional powder adhered to the surface of the constituent fibers of the non-woven fabric. The functional powder is fixed to the porous body by a mixture of a binder and MFC.

The binder is used between the functional powders, between the functional powders and MFCs, between the functional powders and porous bodies, and the MFCs.
And a porous body to form a film between them and adhere and fix them, and preferable examples thereof include acrylic ester resin, NBR, SBR, vinyl chloride resin,
Synthetic resin binder such as ethylene-vinyl acetate copolymer, ethylene-vinyl chloride-vinyl acetate copolymer,
Examples thereof include inorganic binders such as alumina sol, silica sol, smectite, sepiolite, and aluminum silicate.

MFC refers to fine fibrous cellulose having an average weave of 0.1 μm or less. The MFC is, for example, pulp pulp, beaten the fibrils of wood cellulose to physically break the hydrogen bonds between the microfibrils, and bring them into a state close to microfibrils, or biofibrillar cellulose created by microorganisms. and so on. This MFC has a functional group such as a hydroxyl group on the surface of the microfibril, and the functional powder is fixed with a strong adhesive force due to the hydrogen bond of this functional group. Further, the functional powder is also fixed by the entanglement force of MFC microfibrils. Furthermore, when the binder forms a film and adheres, the microfibrils of MFC form a three-dimensional net-like structure, and the functional powder is taken into it to create high voids, so the surface of the functional powder is It is not covered by the binder coating.

As described above, in the functional material of the present invention, the functional powder is reliably fixed to the porous body by the adhesive force of the binder and the binding force and entanglement force of the MFC microfibrils. On the other hand, since the MFC microfibrils take in the functional powder and create a three-dimensional net-like structure, the surface of the functional powder is not covered with the binder film, and Function is not impaired.

Next, the functional material according to claim 2 will be described. This functional material is a binder, MFC and P
A functional powder is fixed to a porous body with a mixture of TFE. In addition, porous body, functional powder,
Since the binder and MFC have been described above, the description here is omitted. Since PTFE has a low friction property, the mixture containing PTFE is less likely to crack.

In this functional material, PTFE may or may not be fibrillated, but when PTFE is fibrillated, the adhesive strength of the binder, the bonding strength of the MFC, and the entanglement strength of the binder. And PTFE
The entanglement force of the microfibrils to the functional powder is also added, and the stronger fixing of the functional powder comes to be achieved. In addition, since the PTFE microfibrils hold voids between the binder and the functional powder, M
With FC, an effective surface due to the functional expression of the functional powder comes to be secured.

Next, a method of manufacturing the functional material according to claim 4 will be described. The method for producing a functional material of the present invention is characterized in that a mixed liquid containing a functional powder, a binder and MFC is applied to a porous body and dried. Since the porous body, the functional powder, the binder, and the MFC have been described above, the description thereof is omitted here. First, the type of the functional powder, the average particle size, etc. are selected according to the application of the functional material. The average particle size of the functional powder is not particularly limited, but if it is too large, it becomes impossible to fix the functional powder in a state in which it is uniformly dispersed in the porous body, and at the same time, per unit weight of the functional powder. The contact area becomes small, and the function of the functional powder cannot be sufficiently exerted on the substance that passes through or contacts the inside of the porous body. MF to this functional powder
After C was added and stirred and mixed, water was added and a binder in the form of an emulsion was added, and further stirred and mixed to obtain a mixed solution.

The amount of the binder (solid content) in this mixed liquid is 1 to 50 with respect to 100 of the functional powder.
Volume part, preferably 5 to 30 volume part. If the amount of the binder is less than this range, the functional powder cannot be sufficiently adhered, and there is a possibility that the functional powder may come off during production or use. On the other hand, when the amount of the binder is larger than this range, the surface of the powder is covered with the binder, and the function of the functional powder is not sufficiently exhibited. Further, the fluidity of the mixed liquid is lost, and there is a risk that smooth application to the porous body may not be possible, and the amount of the functional powder in the mixed liquid is reduced. The amount of MFC is 1 to 30 parts by volume, preferably 5 to 100 parts by volume of the functional powder.
10 parts by volume. If the MFC amount is less than this range, the effects such as binding, entanglement, and retention of voids of the functional powder due to MFC cannot be expected. Become.

The amount of water in the mixed solution is preferably 0.5 to 10 times the weight of the functional powder, although it depends on the type of the functional powder. If the amount of water is smaller than this, the viscosity of the resulting mixed liquid will be high, making it difficult to apply to the porous body, and if the amount of water is larger than this, the functionality that will be substantially fixed to the porous body The amount of powder becomes small and the desired effect cannot be obtained.
When it is desired to fix the functional powder on the surface of the constituent material of the porous body, the amount of water is preferably 0.5 to 10 times, particularly 1 to 5 times. When it is desired to fix it in the voids between the materials, the amount of water is 0.5 to 5 times, especially 0.
It is advisable to reduce the fluidity of the mixture by adjusting the amount to be 5 to 3 times.

Functional powder, binder, MF in the above proportions
After C is added to form a mixed liquid, this is applied to the porous body. A technique such as impregnation, coating or spraying can be used to apply the mixed liquid. By these applying means, the mixed liquid is applied in a state of being uniformly dispersed over the entire porous body, and thereafter, by natural drying or forced drying of the porous body, the water content is evaporated to the surface and the inside of the porous body. The functional powder is fixed by the mixture of the binder and MFC.

Next, a method of manufacturing the functional material according to claim 5 will be described. The method for producing a functional material of the present invention is characterized in that PTFE is further added to the components of the mixed solution used in the production method described in claim 4 and the mixture is applied to a porous body and dried. PTFE has a low friction property, and by including this PTFE in the mixed liquid, the mixed liquid has higher fluidity than in the case of the mixed liquid containing the functional powder, the binder, and MFC. Therefore, it is possible to increase the amount of MFC whose amount to be mixed in the mixed liquid is limited due to the relationship with the fluidity, and it is possible to enhance the effects of fixing the functional powder and securing voids by MFC. Also, by adding PTFE to the components of the mixed liquid, the fluidity becomes higher, and it becomes easier to give the mixed liquid to the porous body, and when this is dried, cracks occur in the mixture fixed to the porous body. It's hard to do.

This PTFE may be added to the mixed solution in the form of powder, but it is better to add it in the form of dispersion in order to facilitate uniform dispersion in the mixed solution. After adding PTFE dispersion to MFC, further mixing with MFC and stirring and mixing, a binder emulsion is added and further stirred and mixed to form a paste-like mixed liquid. The mixed liquid may be prepared in the order of powder → PTFE dispersion → MFC → binder emulsion as described above, but may be prepared in the order of powder → binder emulsion → PTFE dispersion → MFC.
This difference in the mixing order affects the aggregation state of the mixed liquid, particularly the size of the aggregation, and affects the fixed state of the functional powder and the contact state with the substance to be treated treated by the functional powder. Become.

The amount of PTFE in this mixed solution is 0.1 to 70 parts by volume, preferably 0.5 to 20 parts by volume, based on 100 parts by volume of the functional powder. P than this range
If the amount of TFE is large, it will be uneconomical because the amount of increase will not be effective, and if it is less than this range, it will be PTF.
The effect of entanglement of the functional powder due to the addition of E and the retention of voids between the functional powder cannot be expected.

When the PTFE in the mixed solution is fibrillated, the PTFE microfibrils entangle and retain the functional powder, so that the functional powder is more strongly fixed. . In addition, the microfibrils of PTFE maintain voids between the binder and the functional powder, and secure an effective surface due to the functional expression of the functional powder together with MFC. The fibrillation of PTFE can be performed by providing a kneading step after stirring and mixing, or in the process of mixing the respective components,
As a device for fibrillation, a conventionally known mixing stirrer, kneader, ball mill, Banbury mixer, roll mixer, screw mixer or the like can be used. Further, in the case of fibrillating PTFE, fibrillation can be promoted by adding methanol, ethanol, isopropyl alcohol, ethylene glycol, glycerin, ethyl cellosolve or the like to the mixed solution.

[0027]

【Example】

Example 1 Water was added to manganese dioxide (DENMAN RB-S Mitsui Kinzoku Kogyo Co., Ltd.), and then PTFE (D-1 Dispersion (solid content concentration 60 wt%) Daikin Kogyo Co., Ltd.) was added to 100 volumes of manganese dioxide. 20 parts by volume (solid content) and MFC {“Serish K
"Y-100S manufactured by Daicel Chemical Industries, Ltd." in a 2% gel aqueous solution, and "Serisch KY-1"
"00L manufactured by Daicel Chemical Industries Ltd." prepared in 5% gel aqueous solution} is added in an amount of 10 parts by volume (solid content), and the mixture is stirred and mixed with a lab stirrer for 5 minutes, and then a binder emulsion (Sumika Flex 850 manufactured by Sumitomo Chemical Co., Ltd. ( 20 parts by volume (solid content) of vinyl acetate-ethylene-vinyl chloride) was added and stirred and mixed for 5 minutes with a lab stirrer to prepare a paste (water / manganese dioxide ≈1).

A fibrous web made of a side-by-side type composite fiber composed of a polyethylene component and a polypropylene component was passed through a calender at 150 ° C. to coat a heat-bonded non-woven fabric having a basis weight of 15 g / m ^{2 with} the paste, This is dried at a temperature of 130 ° C for 10
After drying for minutes, an ozone decomposition sheet was obtained.

Example 2 An example except that PTFE was not added and MFC was added to 10 parts by volume (solid content) of MFC and 20 parts by volume of binder emulsion (solid content) to 100 parts by volume of manganese dioxide to prepare a paste. An ozone decomposition sheet was obtained in the same manner as in 1.

Comparative Example 1 The same method as in Example 1 was repeated except that 20 parts by volume of PTFE (solid content) and 20 parts by volume of binder emulsion (solid content) were added to 100 parts by volume of manganese dioxide to prepare a paste. An ozone decomposition sheet was obtained.

Comparative Example 2 An ozone decomposition sheet was obtained in the same manner as in Example 1 except that 20 parts by volume (solid content) of the binder emulsion was added to 100 parts by volume of manganese dioxide to prepare a paste.

The initial ozone decomposition rate and the ozone decomposition rate after 30 minutes were examined for Examples 1 and 2 and Comparative Examples 1 and 2 and are shown in FIG. The ozone decomposition rate was measured by the following method.

(Measurement Method of Ozone Decomposition Rate) A test piece obtained by cutting an ozone decomposition sheet into a size of 10 mm × 75 mm was wound around a glass rod together with a mesh (Nisseki Conwednet No. 3330) and put in a glass tube to form a measurement cell. Form. Using an ozone concentration automatic control device (manufactured by EBARA CORPORATION),
Ozone having an ozone concentration of 10 ppm was generated, passed through a measuring cell at a flow rate of 2 l / min, and the ozone concentration after passing was measured to obtain the ozone decomposition rate. However, the measurement was performed at a temperature of 25 ° C.

It can be seen that in the sheet of Comparative Example 2, the ozone decomposing performance after 30 minutes is reduced to less than half and the powder surface contributing to the ozone decomposition is reduced. However, as shown in the graph of Example 2, 60% was obtained by adding 10 parts by volume of MFC.
Similar performance is maintained, and the PTF is as shown in the graph of Example 1.
It can be seen that by adding E, high performance is maintained as compared with Comparative Example 2. This is because when the binder forms a film and adheres, the MFC creates a three-dimensional net-like structure that takes in the powder and creates high voids, so that the powder surface is not covered with the binder. It is thought that it is because. The sheet of Comparative Example 1 is
The ozone decomposition performance was not maintained and did not differ much from the sheet of Comparative Example 2. This is P in the sheet of Comparative Example 1.
This is probably because TFE was hardly fibrillated and the effect of retaining voids around the powder was not sufficiently exerted.

[0035]

According to the present invention, the above-mentioned structure is provided.
In the described functional material, the adhesive strength of the binder,
The binding force and entanglement force of the MFC microfibrils fix the functional powder to the porous body to prevent the functional powder from falling off, and the MFC microfibrils have a three-dimensional net-like structure. Since the powder is created and the powder is taken into the powder and the high voids are maintained, the surface of the functional powder is not covered with the coating film of the binder, and the function of the functional powder is not impaired.

In the functional material according to the second aspect, PTFE is contained in the mixture to prevent cracks from occurring in the mixture.

In the functional material according to claim 3, since the PTFE in the mixture is fibrillated, the adhesive strength of the binder, the bonding strength of the MFC, the entanglement strength, the PTFE, and the like.
The entanglement force of the micro fibrils to the functional powder is also added to achieve stronger fixation of the functional powder, and the micro fibrils of PTFE maintain a void between the binder and the functional powder. Therefore, the effective surface due to the function expression of the functional powder is secured together with the MFC.

In the method for producing a functional material according to claim 4, the functional powder is surely prevented from falling off, and the effective surface is ensured due to the expression of the function of the functional powder. The material can be obtained.

In the method for producing a functional material according to claim 5, since PTFE is added to the components of the mixed liquid and the mixture is applied to the porous body and dried, the mixed liquid is a functional powder. The fluidity is higher than in the case of a mixed solution containing a binder, MFC, and MFC, and the amount of MFC that can be mixed in the mixed solution is limited due to the relationship with the fluidity.
It is possible to obtain a functional material that further enhances the effects of fixing the functional powder and securing voids. Further, by adding PTFE to the components of the mixed solution, the fluidity becomes higher, and it becomes easier to give the mixed solution to the porous body, and when this is dried, cracks are formed in the mixture fixed to the porous body. It can be hard to occur.

In the method for producing a functional material according to claim 6, since the PTFE is fibrillated, the PTFE microfibrils entangle the functional powder and retain it, so that more powerful functionality is obtained. As powder is fixed, P
It is possible to obtain a functional material in which voids are held between the binder and the functional powder due to the TFE microfibrils, and an effective surface due to the functional expression of the functional powder is secured together with MFC.

[Brief description of drawings]

FIG. 1 is an example 1, an example 2, a comparative example 1, and a comparative example 2.
Is a graph showing the initial ozone decomposition rate and the ozone decomposition rate after 30 minutes.

Claims (6)

[Claims] 1. A functional material characterized in that a functional powder is fixed to a porous body by a mixture of a binder and microfibril cellulose. 2. A functional material characterized in that a functional powder is fixed to a porous body by a mixture of a binder, microfibril cellulose and polytetrafluoroethylene. 3. The functional material according to claim 2, wherein the polytetrafluoroethylene in the mixture is fibrillated. 4. A method for producing a functional material, which comprises applying a mixed liquid containing a functional powder, a binder and microfibril cellulose to a porous body and drying the mixture. 5. A method for producing a functional material, which comprises applying a mixed solution containing a functional powder, a binder, microfibril cellulose and polytetrafluoroethylene to a porous body and drying the mixture. 6. The method for producing a functional material according to claim 5, wherein the polytetrafluoroethylene in the mixed solution is fibrillated.