JPH08257360A - Photoreactive material for removing harmful substance - Google Patents

Abstract

PURPOSE: To provide a photoreactive material for removing harmful substance, which is flame-retardant and light fast and has high productivity and processibility. CONSTITUTION: A photoreactive material for removing harmful substance is made of photoreactive semiconductors, fine fibers, polyvinyl chloride fibers, and inorganic fibers optionally together with a carrier and contain 10-60wt.% inorganic fibers. It is preferable that the polyvinyl chloride fibers are one or more kinds of vinyl chloride-vinyl acetate copolymer fibers and vinyl chloride- acrylonitrile copolymer fibers, and the inorganic fiber is glass one.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photoreactive harmful substance removing material, and more specifically, it has flame retardancy and light resistance properties and is excellent not only in practical durability but also in productivity and The present invention relates to a photoreactive harmful substance removing material having excellent processability.

[0002]

2. Description of the Related Art Conventionally, an offensive odor that is industrially generated in factories, and an offensive odor caused by waste in a service industry such as a restaurant or a hotel that discharges a large amount of waste has been a problem. The bad odors in daily life spaces such as in automobiles and general rooms have also been highlighted. Therefore, there is an increasing need for removing these harmful substances such as bad odors, and air purifiers incorporating a bad odor removing device, a bad odor removing filter, etc. are being actively developed.

A filter containing activated carbon is used in a general air cleaner, and a method of adsorbing a harmful substance such as a bad odor to the activated carbon is adopted. However,
Activated carbon has only an adsorptive effect on most harmful substances, and when a certain amount of harmful substances are adsorbed, the filter must be replaced, or due to an increase in ambient temperature or an increase in the concentration of harmful substances, the harmful substances once adsorbed There was a problem that the substance was easily released.

In recent years, in order to solve such problems,
Materials combining activated carbon and a catalyst for decomposing harmful substances have been developed. For example, Japanese Patent Laid-Open No. 1-23472
No. 9 discloses an air conditioner incorporating a deodorant formed by forming a layer of titanium dioxide having photocatalytic ability on the surface of honeycomb-shaped activated carbon. An ultraviolet lamp is attached to the air conditioner, and the deodorant is irradiated with ultraviolet rays to decompose and remove harmful substances adsorbed on the activated carbon by the photocatalytic action of titanium dioxide.

However, since the photocatalyst layer is provided on the surface of the activated carbon in the deodorant, the adsorption action of the harmful substances by the activated carbon is somewhat hindered, or because the contact points between the activated carbon and the photocatalyst are few, the adsorption by the activated carbon is carried out. There is a problem that the harmful substances cannot be effectively decomposed by the photocatalyst. Further, in order to form the photocatalyst layer on the surface of the honeycomb-shaped activated carbon, a process such as impregnation is required, the manufacturing process becomes complicated, and the productivity is slightly inferior.

Japanese Unexamined Patent Publication No. 2-253848 discloses an ozone decomposition catalyst in which an inorganic fibrous carrier carries anatase type titanium oxide, activated carbon, and components having ozone decomposing ability such as manganese, iron, copper, cobalt and nickel. However, in this publication, only the constitution and manufacturing method of the ozone catalyst and the measurement result of the ozone decomposition rate by the ozone decomposition catalyst are shown, and regarding the harmful substance removing material using the ozone decomposition catalyst, Nothing was shown.

Japanese Unexamined Patent Publication (Kokai) No. 3-233100 discloses a ventilation facility for a tunnel of a motorway, which comprises a mixture of titanium dioxide, activated carbon, and an iron-based metal compound, and a light source for irradiating the mixture with light having a wavelength of 300 nm or more. There is. As a harmful substance removing material to be mounted on the ventilation equipment for a tunnel for a motorway, a mixed powder of titanium dioxide, activated carbon and iron oxide pulverized to a submicron order is attached on an adhesive applied to the outer peripheral surface of a glass tube. Examples are a reaction tube having the ability to remove harmful substances, or a filter formed by adhering a mixed powder of titanium dioxide and iron oxide on the surface of a non-woven fabric made of a resin mixed with activated carbon powder. However,
In the harmful substance removing material, since the photocatalyst such as titanium dioxide is fixed to the base material with an adhesive, a part of the surface of the photocatalyst is covered with the adhesive, the effective surface area of the photocatalyst is reduced, and the photocatalytic action is reduced. There was a problem.

Japanese Unexamined Patent Publication (Kokai) No. 4-256755 discloses a photoreactive harmful substance removing material composed of granular pulp carrying a photoreactive semiconductor such as titanium dioxide. The photoreactive harmful substance removing material has a granular shape of 1 to 30 mm, which is convenient when it is used by filling it in a container or the like, but since it is not a shape such as a sheet that can be easily processed,
There is a problem that the range of use is limited.

In these prior arts, the emphasis is placed on effective removal of odorous substances and the like, and little consideration is given to the actual use environment. For example, there is almost no countermeasure against deterioration and discoloration of a base material due to ultraviolet rays, which is essential for the expression of a photocatalytic action, and the usage range has been limited at present.

As a method for solving such a problem, in Japanese Patent Application No. 7-8425 filed by the present applicant, a photoreactive semiconductor such as titanium dioxide is supported on a carrier,
A method of suppressing deterioration and discoloration of a substrate due to the photocatalytic action of a photoreactive semiconductor has been proposed. However, in this method, the deterioration and discoloration of the base material itself due to ultraviolet rays are not sufficiently taken into consideration, and even if the deterioration and discoloration of the base material due to the photocatalytic action can be reduced, the base material itself When it is used for a long period of time because it is deteriorated and discolored by ultraviolet rays, there remains a problem to be improved in terms of its durability.

[0011]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned problems and has not only excellent flame resistance and light resistance and excellent practical durability, but also productivity and It is an object of the present invention to provide a photoreactive harmful substance removing material having excellent processability.

[0012]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have invented a photoreactive harmful substance removing material.

That is, the photoreactive harmful substance removing material of the present invention comprises a photoreactive semiconductor, a fine fiber, a polyvinyl chloride fiber, and an inorganic fiber.
It is characterized in that it is contained by weight%.

It is preferable that the photoreactive harmful substance removing material contains a carrier.

In the photoreactive harmful substance removing material of the present invention, the polyvinyl chloride fiber is preferably one or more of vinyl chloride / vinyl acetate copolymer fiber and vinyl chloride / acrylonitrile copolymer fiber.

In the photoreactive harmful substance removing material of the present invention, the inorganic fibers are preferably glass fibers.

The photoreactive harmful substance removing material of the present invention is characterized by being manufactured by a wet papermaking method.

The photoreactive harmful substance removing material of the present invention will be described in detail below.

First, the photoreactive semiconductor will be described below. The photo-reactive semiconductor used in the present invention is 0.
It is a semiconductor that causes a photocatalytic reaction having a band gap of 5 to 5 eV, preferably 1 to 3 eV, and harmful substances are decomposed by OH radicals generated in the photoreactive semiconductor. The shape of the photoreactive semiconductor is preferably in the form of particles, and particles having a specific surface area of 10 to 500 m ² / g are appropriately selected and used.

Examples of such photoreactive semiconductors include those disclosed in JP-A-2-273514, and zinc oxide, tungsten trioxide,
Metal oxides such as titanium oxide and cerium oxide are preferable, and among these, titanium oxide is a particularly preferable material in view of structural stability, ability as a photoreactive semiconductor, handling safety, and the like. As titanium oxide, in addition to titanium dioxide, hydrous titanium oxide, hydrated titanium oxide, metatitanic acid, orthotitanic acid, titanium hydroxide and the like can be used, and the crystal form thereof is not particularly limited. When titanium oxide is used, its specific surface area is preferably 50 to 400 m ² / g. Further, the surface of titanium oxide may be coated with a metal such as platinum, gold, silver, palladium, rhodium or ruthenium, or a metal oxide such as ruthenium oxide or nickel oxide.

The content of the photoreactive semiconductor is preferably 1 to 30% by weight based on the total weight of the photoreactive harmful substance removing material. If it is less than 1% by weight, the photocatalytic action is insufficient, and the ability to decompose and remove harmful substances decreases, which is not preferable. On the other hand, 3
When the content is more than 0% by weight, the ability to decompose and remove harmful substances is improved, but it becomes difficult to firmly hold the photoreactive semiconductor in the photoreactive harmful substance removing material, and productivity due to powder falling etc. It is not preferable because the photoreactive semiconductor, which is deteriorated in workability, or which has fallen off, scatters to other parts of the photoreactive harmful substance removing material, causing deterioration and discoloration of the substrate.

Next, the fine fibers will be described below. Examples of the fine fibers used in the present invention include those processed by the following method. (1) A method of causing a synthetic polymer solution to flow into a poor solvent for the polymer while applying a shearing force to precipitate fibrous fibrils (fibrid method, Japanese Patent Publication No. 35-11851). (2) Applying shearing force while polymerizing the synthetic monomer,
Method of precipitating fibrils (polymerization shearing method, Japanese Patent Publication No. 4)
7-21898). (3) A method in which two or more types of incompatible polymers are mixed, melt-extruded, or spun, cut, and then fibrillated by a mechanical means (split method, JP-B-35-96).
No. 51). (4) A method in which two or more incompatible polymers are mixed, melt-extruded or spun, cut, and then immersed in a solvent to dissolve one of the polymers to form fibrils (polymer blend dissolution) Law, U.S. Pat. No. 3,382,305). (5) A method in which a synthetic polymer is explosively ejected from the high-pressure side to the low-pressure side above the boiling point of its solvent and then fibrillated into a fibrous state (flash spinning method, JP-B-36-164).
No. 60 publication). (6) A method in which a polyester-based polymer is blended with an insoluble alkali-soluble component in the polyester, and after molding, the mixture is reduced with an alkali and then beaten to form fibrils (alkaline weight loss beating method, JP-B-56- 315). (7) Cellulose fiber, high crystallinity such as Kevlar fiber,
A method in which highly oriented fibers are cut into suitable fiber lengths, dispersed in water, and then fibrillated using a homogenizer, a beater, etc. (JP-A-56-100801).

The fine fibers of the present invention are fibrillated by the above-mentioned special method, and the average diameter of the fibrils constituting the fibers is extremely small, 1 μm or less. Therefore, the specific surface area of the fiber is extremely large, and it is possible to fix the photoreactive semiconductor on the fiber in a large amount and uniformly.

The content of the fine fibers is preferably 0.1 to 10% by weight based on the total weight of the photoreactive harmful substance removing material. 0.1
If the content is less than 5% by weight, the ability to retain the photoreactive semiconductor will be insufficient, and the productivity and processability will be reduced due to the photoreactive semiconductor falling off. It is not preferable because it scatters on the substrate and causes deterioration and discoloration of the substrate. When the amount is more than 10% by weight, the photoreactive semiconductor has a large retaining ability, but it becomes a dense photoreactive harmful substance removing material, so that it becomes difficult for the harmful substance to contact the photoreactive semiconductor, and the harmful substance is removed. Is not preferable because it cannot be effectively performed.

Next, the polyvinyl chloride fiber will be described below. As the polyvinyl chloride fiber used in the present invention, a homopolymerized fiber of vinyl chloride or a conventionally known fiber such as vinyl chloride and another polymer, for example, vinyl acetate, acrylonitrile, a copolymerized fiber of vinylidene chloride and the like. Although it can be widely used, for homopolymerized fibers, the fiber performance and its application value are limited, so copolymer fibers such as vinyl chloride / vinyl acetate copolymer fibers and vinyl chloride / acrylonitrile copolymer fibers are more preferable. It is the preferred material.

Since polyvinyl chloride contains chlorine in its molecule and is nonflammable, the polyvinyl chloride fiber has a high level of flame retardancy. Therefore, the photoreactive harmful substance removing material of the present invention obtained by mixing the fibers has a high degree of flame retardancy.

The photoreactive harmful substance removing material of the present invention decomposes and removes harmful substances by the photocatalytic action of the photoreactive semiconductor, and requires an ultraviolet ray source such as sunlight or a black lamp when used. Is. However, most of the organic fibers are deteriorated and discolored by ultraviolet rays, so that there is no choice but to limit their use period and intended use.

Since the polyvinyl chloride fiber has sufficient resistance to deterioration and discoloration by ultraviolet rays, the photoreactive harmful substance removing material of the present invention containing the polyvinyl chloride fiber is The substrate itself exhibits good light resistance. Since the photoreactive semiconductor that exhibits photocatalytic action by ultraviolet rays is fixed on the fine fibers and held in the photoreactive harmful substance removing material, there is not much contact between the base material and the photoreactive semiconductor. The photoreactive harmful substance removing material of the present invention in which the substrate has sufficient light resistance has practical durability against ultraviolet rays.

Further, since the polyvinyl chloride fiber has thermoplasticity and effectively acts as a binder, it is insufficient in resistance to ultraviolet rays and flame retardancy as a constituent material of the photoreactive harmful substance removing material. The organic binder does not have to be used in combination, and even if it is necessary, the amount used can be suppressed to a small amount, so the flame retardancy and light resistance of the photoreactive harmful substance removing material will not be greatly impaired. Absent.

The content of the polyvinyl chloride fiber is preferably 20 to 80% by weight, more preferably 30 to 70% by weight based on the total weight of the photoreactive harmful substance removing material. If it is less than 20% by weight, the adhesive ability is insufficient and it does not serve as a photoreactive harmful substance removing material that can withstand practical use, which is not preferable. If it exceeds 80% by weight, the amount of the other constituent materials blended becomes small, and it does not function effectively as a photoreactive harmful substance removing material, which is not preferable. In consideration of papermaking properties, the fineness of the fiber is 0.1 to 15 denier and the fiber length is 1 to 20 mm.
It is preferred that

Next, the inorganic fiber will be described below. In addition to the above, the polyvinyl chloride fiber has properties such as a low softening point and a large heat shrinkage. Due to these properties, only the photoreactive semiconductor, the fine fiber, and the polyvinyl chloride fiber are used. In the photoreactive harmful substance removing material constituted, for example, in the drying step after wet papermaking, the photoreactive harmful substance removing material is soft and soft until the temperature of the photoreactive harmful substance removing material is sufficiently lowered. Since there is no problem, problems such as paper breaks and large elongation in the machine traveling direction are likely to occur, and even if these problems are solved successfully, the basis weight of the photoreactive harmful substance removing material due to heat shrinkage However, there was a manufacturing problem that the thickness and width were not stable.

The inorganic fiber of the present invention is used for solving the above-mentioned problems, and glass fiber, carbon fiber, metal fiber, ceramic fiber and the like can be appropriately used.

Since the inorganic fiber is rich in rigidity and excellent in dimensional stability, it is possible to solve the above problems by using the inorganic fiber. Further, since the inorganic fiber has nonflammability, high flame retardancy, and sufficient light resistance, it does not impair the flame resistance and light resistance as the photoreactive harmful substance removing material. Furthermore, by using inorganic fibers, in the drying step during manufacturing, for example, when a cylinder dryer or a Yankee dryer is used, the peelability of the polyvinyl chloride-based fibers, which tend to be sticky, from the dryer surface is also improved. is there.

Among the inorganic fibers, glass fiber is a particularly preferred material because it is relatively inexpensive, readily available in a wide range of fiber diameters and lengths, and has good water dispersibility during wet papermaking. is there.

The glass fiber has an average fiber diameter of 6 to 2
0 μm chopped strand glass fibers and ultrafine glass fibers having an average fiber diameter of 0.3 to 4 μm can be appropriately combined and used. By appropriately selecting the fiber diameter and the compounding amount of the glass fiber, it is possible to arbitrarily adjust the yield of the composite of the photoreactive semiconductor and the fine fiber and the drainage of the aqueous slurry.

The content of the inorganic fibers is preferably 10 to 60% by weight based on the total weight of the photoreactive harmful substance removing material. If the amount is less than 10% by weight, the above-mentioned effects due to the mixing of inorganic fibers cannot be sufficiently exhibited, which is not preferable. If it is more than 60% by weight, it becomes a photoreactive harmful substance removing material lacking in flexibility, and cracks frequently occur during production, and folding property is poor and processability is poor, which is not preferable.

Next, the carrier will be described below. The carrier used in the present invention is for supporting a photoreactive semiconductor. As described above, in the photoreactive harmful substance removing material of the present invention, not only the base material itself has light resistance, but also the photoreactive semiconductor which may deteriorate or discolor the base material due to the photocatalytic action is formed on the fine fiber. Since it is fixed on and retained in the photoreactive harmful substance removing material, the contact portion between the base material and the photoreactive semiconductor is not so much, and there is little deterioration or discoloration due to the photocatalytic action.

However, the contact portion between the photoreactive semiconductor and the substrate is not completely absent, and there is a possibility that the contact portion gradually deteriorates and discolors when used for a long period of time. Therefore, by supporting the photoreactive semiconductor on the carrier to further reduce the contact portion between the base material and the photoreactive semiconductor, deterioration and discoloration of the photoreactive harmful substance removing material of the present invention can be further reduced. can do.

Further, it is also possible to use a carrier having an adsorption ability for a malodorous substance. In this case, the malodorous substance adsorbed by the carrier can be decomposed and removed by the photoreactive semiconductor, so that it is extremely high. Deodorizing performance can be obtained. In addition, a carrier having a catalytic action is also one of the preferable materials.

Specific examples include activated carbon, zeolite, iron-based compounds such as iron oxide, zinc oxide, magnesium oxide, aluminum oxide, silica, silica-zinc oxide composite, silica-alumina-zinc oxide composite, composite. Examples thereof include phyllosilicates and mixtures thereof.
The shape of these carriers is not particularly limited, but in consideration of the carrying ability of the photoreactive semiconductor, a particulate form is preferable, and a specific surface area of 50 to 2000 m ² / g is appropriately selected. It is possible to use, for example, in the case of activated carbon, those of 500 to 1500 m ² / g are preferable.

The content of the carrier is preferably 1 to 20% by weight of the weight of the photoreactive harmful substance removing material. If it is less than 1% by weight, the supporting ability of the photoreactive semiconductor is insufficient, and the above-mentioned effects associated with the use of the carrier cannot be sufficiently exhibited, which is not preferable. When the amount is more than 20% by weight, the ability of supporting the photoreactive semiconductor is large, but the carrier-covered portion of the surface of the photoreactive semiconductor increases, and the photocatalytic ability decreases, which is not preferable.

The main fibers of organic synthetic fibers such as polyester fiber, polyacrylonitrile fiber, polyvinyl alcohol fiber, regenerated fiber, polyamide fiber and the like, as long as the characteristics of the photoreactive harmful substance removing material of the present invention are not impaired, Any organic natural fiber such as binder fiber, wood pulp, cotton linter pulp, or hemp pulp may be used.

Next, a method for producing the photoreactive harmful substance removing material of the present invention will be described below. First, the photoreactive semiconductor and the carrier are sequentially added to water, and the photoreactive semiconductor is adsorbed on the carrier to form a complex of the photoreactive semiconductor and the carrier. Then, the fine fibers are mixed, and an appropriate flocculant is used to form an aggregated complex of the complex and the fine fibers. As the aggregating agent, for example, a cationic polyacrylic amide,
Cationic polymeric flocculants such as polyaluminum chloride can be used.

Further, an anionic polymer flocculant that forms a complex with these cationic polymer flocculants to enhance aggregation, such as anionic polyacrylic amide, may be used in combination. An aqueous slurry is prepared by mixing a disaggregated mixture of polyvinyl chloride fibers and inorganic fibers with the aggregate composite. For even dispersion in water,
The solid content concentration of the aqueous slurry is preferably 0.1 to 5% by weight.

A web is formed from the aqueous slurry by using a paper machine for producing general paper or a wet non-woven fabric, for example, a Fourdrinier paper machine, a cylinder paper machine, a slanted wire paper machine, press and dry. Then, a photoreactive harmful substance removing material is manufactured. A cylinder dryer, a Yankee dryer, an air dryer or the like can be used to dry the web.

The photoreactive harmful substance removing material containing no carrier can be produced by the same method as described above except that the carrier is not contained.

[0047]

The photoreactive harmful substance removing material according to the present invention is capable of removing malodorous substances, bacteria, etc. by the photocatalytic action of the photoreactive semiconductor uniformly and effectively retained in the photoreactive harmful substance removing material by fine fibers. Its effect lasts for a long time because it decomposes and removes harmful substances.

The polyvinyl chloride fiber is not only excellent in flame retardancy and light resistance, but also has thermoplasticity and effectively acts as a binder. Therefore, other organic components lacking in flame retardance and light resistance are used. Does not need to be used, and even if it is necessary, the amount used can be suppressed to a small amount, so that flame retardancy and light resistance as a photoreactive harmful substance removing material are not impaired. Since the photoreactive semiconductor that exhibits photocatalytic action by ultraviolet rays is fixed on the fine fibers and held in the photoreactive harmful substance removing material, there is not much contact between the base material and the photoreactive semiconductor. The photoreactive harmful substance removing material of the present invention in which the substrate has sufficient light resistance has practical durability against ultraviolet rays.

By mixing the inorganic fibers,
Not only it is possible to avoid various troubles in the manufacturing process of the photoreactive harmful substance removing material due to the thermal characteristics of the polyvinyl chloride fiber, but also by appropriately selecting the fiber diameter and blending amount of the inorganic fiber. It is also possible to arbitrarily adjust the yield of the composite of the photoreactive semiconductor and the fine fibers and the drainage of the aqueous slurry.

Further, by supporting the photoreactive semiconductor on the carrier, the contact portion between the photoreactive semiconductor and the substrate is further reduced, and the photoreactive harmful substance removing material is deteriorated by the photocatalytic action of the photoreactive semiconductor. The discoloration can be further reduced. If a carrier having adsorption ability and catalytic ability for harmful substances is used as the carrier, it is possible to remove the harmful substances more effectively.

Therefore, the photoreactive harmful substance removing material of the present invention has properties of flame retardancy and light resistance, and is excellent not only in practical durability but also in processability, so that it has various shapes. It can be processed into various materials and used as a harmful substance removing material under various usage environments. It is used for deodorizing filters in general rooms and automobiles, curtains and sheets for partitioning hospital beds, and partitioning for smoking rooms. Effectively acts as a curtain. Further, it has excellent productivity and can be easily manufactured by using an ordinary paper machine or the like.

[0052]

The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

Examples 1 to 6 [Preparation of Aqueous Slurry of Aggregated Composite] Titanium dioxide powder (P25 manufactured by Nippon Aerosil Co., Ltd.) was used as a photoreactive semiconductor.
S6); as fine fibers, fine cellulose (Cerish KY-100S manufactured by Daicel Chemical Industries, Ltd.) was added and mixed in water as a composition (% by weight) shown in Table 1, and then polyaluminum chloride (Mizuzawa) was used as a coagulant. An appropriate amount of PAC manufactured by Kagaku Kogyo Co., Ltd. was added to prepare an aqueous slurry of a photoreactive semiconductor and an agglomerated complex of fine fibers. In Example 6, activated carbon powder (manufactured by Takeda Pharmaceutical Co., Ltd.) was added and mixed as a carrier.

[Preparation of Aqueous Slurry of Disaggregation Mixture] As polyvinyl chloride fiber, vinyl chloride / vinyl acetate copolymer fiber (manufactured by Mitsubishi Rayon Co., VF, fineness 3 denier, fiber length 6 mm), vinyl chloride / acrylonitrile copolymerization Fiber (Kanebuchi Chemical Co., Kanekaron, fineness 3 denier, fiber length 6 mm); As inorganic fiber, glass fiber (Asahi Fiber Glass Co., Ltd., fiber diameter 6 μm, fiber length 6 mm), ultrafine glass fiber (Schuler, average) Fiber diameter 2.7 μm), carbon fiber (Toho Rayon Co., Vesphite, fiber diameter 7 μm
m, fiber length 6 mm); was added and mixed in water according to the formulation shown in Table 1 to prepare an aqueous slurry.

[Preparation of Photoreactive Hazardous Substance Removing Material] The above-mentioned aqueous slurry of the aggregated complex and the aqueous slurry of the disaggregation mixture were mixed and diluted with water to prepare an aqueous slurry having a raw material concentration of 0.25% by weight. After that, an appropriate amount of anionic polyacrylic amide (Acrypers, manufactured by Diafloc Co., Ltd.) was added, and the basis weight of the aqueous slurry was 100 using a cylinder paper machine.
A g / m ² photoreactive harmful substance removing material was prepared.

Comparative Example 1 Polyvinyl chloride fiber was replaced with aramid fiber (manufactured by DuPont,
Nomex, fineness 2 denier, fiber length 5 mm) 40% by weight, aramid pulp (Dupont, Fibrid)
A photoreactive harmful substance removing material was prepared in the same manner as in Example 1 except that the material was replaced with 10% by weight.

Comparative Example 2 Polyvinyl chloride fiber was used as PPS fiber (manufactured by Toray Industries, Inc., fineness 2
40% by weight of denier, fiber length 5 mm) and 10% by weight of flame-retardant vinylon fiber (Kuraray Co., Ltd., VPX-201 × 3, fineness 2 denier, fiber length 3 mm).
A photoreactive harmful substance removing material was produced in the same manner as in Example 1.

Comparative Example 3 Polyvinyl chloride fiber was replaced with aramid fiber (manufactured by DuPont,
Nomex, fineness 2 denier, fiber length 6 mm) 30% by weight, aramid pulp (Dupont, Fibrid)
A photoreactive harmful substance removing material was produced in the same manner as in Example 6 except that the material was replaced with 10% by weight.

Comparative Example 4 Light was produced in the same manner as in Example 1 except that the inorganic fiber was replaced with vinyl chloride / vinyl acetate copolymer fiber (manufactured by Mitsubishi Rayon Co., VF, fineness 3 denier, fiber length 6 mm). A reactive harmful substance removing material was produced.

Comparative Example 5 A photoreactive harmful substance removing material was prepared in the same manner as in Example 1, except that the inorganic fiber was replaced with a polyester fiber (manufactured by Teijin Ltd., fineness: 0.5 denier, fiber length: 5 mm). It was made.

Comparative Example 6 and Comparative Example 7 In Example 1, the blending amount of polyvinyl chloride fiber / inorganic fiber was 50% by weight / 38% by weight to 80% by weight / 8.
A photoreactive harmful substance removing material was produced in the same manner as in Example 1 except that the weight% (Comparative Example 6) and 23% / 65% by weight (Comparative Example 7) were used.

[0062]

[Table 1]

The deodorizing performance, antibacterial property, flame retardancy, light resistance, productivity and processability of the photoreactive harmful substance removing materials prepared in the above Examples and Comparative Examples were evaluated by the following methods, and the results were evaluated. Table 2 for Examples and Table 3 for Comparative Examples
It was shown to.

[Deodorizing performance] 1 material for removing photoreactive harmful substances
It was cut into 0 cm × 20 cm and left to stand on the bottom of a 5.6 L closed container equipped with a 6 W black lamp. After injecting 4 mL of saturated acetaldehyde into this container (concentration of about 5
00ppm), about 20c above the photoreactive harmful substance removing material
Ultraviolet rays were irradiated from a black lamp of m to 6 W, and after 30 minutes, the acetaldehyde concentration (ppm) in the container was quantified by gas chromatography. Then, the same operation was continuously repeated twice.

[Antibacterial] 10 photoreactive harmful substance removing materials
It was cut into cm × 10 cm, immersed in an aqueous solution of Pseudomonas aeruginosa with a concentration of 70,000 cells / mL, and irradiated with ultraviolet rays for 4 hours from about 20 cm above the photoreactive harmful substance removing material using a 6 W black lamp. After irradiation, the viable cell count of Pseudomonas aeruginosa was measured by the pour plate culture method (culture at 35 ° C. for 48 hours) using a standard agar medium, and the Pseudomonas aeruginosa concentration was calculated. The reduction rate (%) of Pseudomonas aeruginosa concentration after ultraviolet irradiation was used as an index of antibacterial property.

[Flame Retardancy] The flammability of the photoreactive harmful substance removing material was evaluated according to the JIS A109 method A-1.
It is indicated by the flammability category.

[Light resistance] The light resistance of the photoreactive toxic substance removing material was determined by irradiating the photoreactive toxic substance removing material with ultraviolet rays for 72 hours using a xenon arc fade odometer (manufactured by Toyo Seiki Seisakusho). It was evaluated based on the retention rate (%) of tensile strength after ultraviolet irradiation and the presence or absence of discoloration. Tensile strength is
According to JIS P8113, the photoreactive harmful substance removing material is 25 mm in width and 20 in length in the vertical and horizontal directions.
It was cut to 0 mm and measured with a tensilon measuring machine (HTM-100 manufactured by Orientec Co., Ltd.). The presence or absence of discoloration of the photoreactive harmful substance removing material was visually determined.

[Productivity] The productivity was evaluated based on the paper-making condition when the photoreactive harmful substance removing material was made with a cylinder paper machine. When troubles such as paper breakage, sheet sticking to the dryer, powder drop-off, and sheet width shrinkage do not occur, the symbol is ○, and when any of the troubles occurs, symbol ×
Displayed in.

[Machinability] The machinability of the photoreactive harmful substance removing material was evaluated by visually observing the state of cracking and powder falling during pleating. When cracking and powder drop-off were not observed, it was indicated by the symbol o, and when cracking or powder drop-off was observed, it was indicated by the symbol x.

[0070]

[Table 2]

[0071]

[Table 3]

The photoreactive harmful substance removing materials of Examples 1 to 5 are not only excellent in the ability to remove odorous substances and bacteria upon irradiation with ultraviolet rays, but also have flame retardancy and light resistance, and have excellent productivity and processability. Was also excellent.

The photoreactive toxic substance removing material of Example 6 containing a carrier has a capability of removing a malodorous substance as compared with the photoreactive toxic substance removing materials of Examples 1 to 5 containing no carrier. And the light resistance (tensile strength retention rate) was slightly excellent. It is considered that the activated carbon having the adsorptivity was used as the carrier and that the contact portion between the photoreactive semiconductor and the substrate was further reduced by the use of the carrier.

Although the photoreactive harmful substance removing material of Comparative Example 1 has flame retardancy, the tensile strength after irradiation of ultraviolet rays decreases.
Yellowing was observed and the light resistance was poor.

The photoreactive harmful substance removing material of Comparative Example 2 has flame retardancy as in Comparative Example 1, but shows a decrease in tensile strength and yellowing after irradiation of ultraviolet rays, and is inferior in light resistance. It was Furthermore, in the photoreactive harmful substance removing material, the photocatalytic activity of the photoreactive semiconductor was decreased. It is considered that the vinylon fiber melted and covered the surface of the photoreactive semiconductor, and the effective surface area of the photoreactive semiconductor decreased.

Although the photoreactive harmful substance removing material of Comparative Example 3 contained a carrier, it was also inferior in light resistance as in Comparative Examples 1 and 2.

The photoreactive harmful substance removing material of Comparative Example 4 does not contain inorganic fibers, and troubles such as paper breakage and sheet width shrinkage occur in the drying step after wet papermaking, resulting in poor productivity. It was a thing.

The photoreactive harmful substance removing material of Comparative Example 5 is
It was a mixture of organic fibers instead of inorganic fibers, and was inferior in flame retardancy. Further, the same troubles as those of the photoreactive harmful substance removing material of Comparative Example 4 occurred during production, and the productivity was also poor.

The photoreactive toxic substance removing material of Comparative Example 6 has a low mixing ratio of inorganic fibers, and the same troubles as those of the photoreactive toxic substance removing material of Comparative Example 4 occur at the time of production, resulting in poor productivity. Met.

The photoreactive harmful substance removing material of Comparative Example 7 had a high mixing ratio of inorganic fibers and lacked flexibility, and therefore, there were problems such as paper cutting troubles due to cracks and cracks during fold-folding. It was inferior in both workability and workability.

[0081]

INDUSTRIAL APPLICABILITY The photoreactive harmful substance removing material of the present invention not only can decompose and remove harmful substances such as malodorous substances and bacteria by photocatalytic action, but also has flame retardancy and light resistance, and has practical durability. It is also excellent in workability and workability. Therefore, the photoreactive harmful substance removing material of the present invention can be processed into various shapes and can be utilized as a harmful substance removing material under various usage environments. It works effectively as a filter, curtains and sheets for hospital beds, and curtains for smoking rooms. Further, it has excellent productivity and can be easily manufactured by using an ordinary paper machine or the like.

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Claims (5)

[Claims] 1. A photoreactive semiconductor, a fine fiber, a polyvinyl chloride fiber, and an inorganic fiber.
A photoreactive harmful substance removing material, characterized by containing 0 to 60% by weight. 2. The photoreactive harmful substance removing material according to claim 1, wherein a carrier is contained in the photoreactive harmful substance removing material. 3. The polyvinyl chloride fiber is vinyl chloride.
3. The photoreactive harmful substance removing material according to claim 1, which is one or more kinds of vinyl acetate copolymer fiber or vinyl chloride / acrylonitrile copolymer fiber. 4. The photoreactive harmful substance removing material according to claim 1, wherein the inorganic fiber is a glass fiber. 5. The photoreactive harmful substance removing material is produced by a wet papermaking method.
5. The photoreactive harmful substance removing material according to any one of 4 to 4.