JP2022087877A - Fiber sheet - Google Patents

Abstract

To provide a fiber sheet on whose surface, a medicine is fastened without a resin binder, the fiber sheet comprising an antiallergenic performance and antiviral performance and exhibiting sufficiently, a function of a functional medicine, and being preferably used for air filter application.SOLUTION: There is provided a sheet formed of a fiber, on a surface of the fiber, a water soluble polyphenol is adhered, and to the water soluble polyphenol adhered to the surface of the fiber, one kind or more kinds selected from a non-water soluble antibacterial and/or anti fungal agent, and a fire retardant, are adhered.SELECTED DRAWING: None

Description

The present invention relates to a fiber sheet suitably used for air filter applications.

Conventionally, an air filter has been used to remove pollen, dust, etc. in a gas and purify the air. In recent years, the air filter is required to have various functions according to the needs of consumers in addition to removing pollen and dust.

For example, Patent Document 1 discloses a functional sheet to which a fungicide is attached using a resin binder. In recent years, with the improvement of living standards, awareness of hygiene has been increasing, and products and technologies with antifungal treatment have been put into practical use in each field of clothing, food and housing, and it is requested that filters be given antifungal properties. Has been done.

Patent Document 2 discloses a functional sheet to which a flame retardant is attached using a resin binder. Filters attached to air conditioners for automobiles, air purifiers for home use, and filters for buildings and factories are required to be flame-retardant from the viewpoint of preventing fires in products and buildings.

Patent Document 3 discloses a sheet in which an anti-allergen agent is attached to a filter sheet with a resin binder. As a method of removing allergens from the living environment, a method of filtering and collecting allergens such as house dust, mites, and pollen existing in the environment using an air filter like an air purifier has been studied for a long time. However, the allergens collected by the air filter retain allergic activity. Therefore, it is possible that the allergen re-scatters when the air filter is processed, and the allergen comes into contact with the re-scattered allergen. Therefore, in order to reliably remove allergens so that allergic patients do not come into contact with them, it is necessary to inactivate the allergens when they are captured by an air filter, and it is required to impart antiallergen properties. There is.

In addition, there is an increasing need for a sheet that combines these technologies and has multiple functions such as antibacterial, antifungal, flame-retardant, and anti-allergen properties.

Japanese Patent Application Laid-Open No. 2003-166155 Japanese Unexamined Patent Publication No. 2010-227758 Japanese Unexamined Patent Publication No. 2011-132417

However, in the sheets of Patent Documents 1 to 3, a drug for imparting a function is attached with a resin binder. Therefore, since the surface of the drug adheres while being covered with the resin binder, there is a concern that the functionality of the drug may be lower than it should be.

Therefore, the present invention has anti-allergen performance and anti-virus performance by adhering a functional agent to the fiber surface by utilizing the adhesiveness of a water-soluble polyphenol having a protein denaturing action without using a resin binder. Moreover, an excellent fiber sheet in which the function of the functional agent is fully exhibited is provided.

The fiber sheet of the present invention that solves the above problems is a sheet made of fibers, in which water-soluble polyphenols are attached to the surface of the fibers, and the water-soluble polyphenols attached to the fibers are water-insoluble. A functional agent composed of one or more selected from the group consisting of antibacterial and / or antifungal agents and flame retardants is attached.

The filter of the present invention uses the sheet of the present invention.

According to the present invention, a functional agent can be attached to a fiber constituting a fiber sheet by using a water-soluble polyphenol having a protein denaturing action. Since the resin binder is not used for adhering the functional drug, not only the effect of the functional drug can be sufficiently exhibited, but also the anti-allergen performance and antiviral property of the water-soluble polyphenol can be sufficiently exhibited.

Hereinafter, the present invention will be described in detail.

In the fiber sheet of the present invention, a water-soluble polyphenol is attached to the surface of the fiber, a functional agent is further attached to the water-soluble polyphenol, and the functional agent is fixed to the fiber surface by adhering to the water-soluble polyphenol. ..

It is considered that the fiber sheet of the present invention adopting such a structure exerts the effect of the present invention by the following mechanism. First, as described above, in order to fix the functional agent on the fiber surface, a resin binder such as a general acrylic resin or urethane resin is not used, but the adhesiveness of water-soluble polyphenol is used. Therefore, since the functional agent adheres to the water-soluble polyphenol adhering to the fiber surface, the functionality caused by the protein denaturing action of the water-soluble polyphenol, specifically, the anti-allergen performance and the antiviral property and the function of the functional agent. It becomes a fiber sheet that also has. In addition, since no resin binder is used, the functionality (anti-allergen performance and anti-virus property) of the water-soluble polyphenol itself is not impaired.

Hereinafter, the members and the like used for the fiber sheet of the present invention will be described.

The base material of the fiber sheet is not particularly limited, and can be arbitrarily selected from air-laid non-woven fabric, wet non-woven fabric, spunbond non-woven fabric, melt blow non-woven fabric, thermal bond non-woven fabric, stitch bond non-woven fabric, needle punch non-woven fabric, spun lace non-woven fabric and the like. Among them, when flame retardancy is required as a fiber sheet, it is preferable that the base material is molded without using a resin binder. Examples of the base material molded without using a resin binder include spunbonded nonwoven fabrics, melt-blown nonwoven fabrics, thermal-bonded nonwoven fabrics, stitch-bonded nonwoven fabrics, and the like.

A water-soluble polyphenol refers to an aromatic hydroxy compound having two or more hydroxyl groups (hydroxy groups), such as catechins, tannic acid compounds, hydroxybenzoic acid compounds, aromatic hydroxy compounds, or salts thereof. A polymer or the like can be used.

The content of the water-soluble polyphenol is preferably 0.1 to 50% by mass, more preferably 3 to 40% by mass, based on the total mass of the fiber sheet. By setting the content of the water-soluble polyphenol to 0.1% by mass or more, the anti-allergen performance and anti-virus property of the fiber sheet become excellent. On the other hand, by setting the content of the water-soluble polyphenol to 50% by mass or less, the occurrence of clogging of the fiber sheet can be further suppressed, and the increase in the pressure loss when the air filter is used can be further suppressed. can.

Photooxidation of water-soluble polyphenols may cause the fiber sheet to turn brown. This discoloration of the fiber sheet may raise performance doubts to the general user. Therefore, it is preferable to color the fiber sheet by using a colorant in the method for producing a fiber sheet described later. By coloring, the discoloration of the water-soluble polyphenol can be made inconspicuous. As the colorant, a water-soluble azo dye that does not react with the water-soluble polyphenol and an anthraquinone-based disperse dye can be processed in the same bath, which is preferable.

The functional agent is composed of one or more selected from the group consisting of water-insoluble antibacterial and / or antifungal agents and flame retardants. In addition, depending on the intended use, any functional agent that does not impair the effects of the present invention may be used in combination.

The functional agent adheres to the water-soluble polyphenol attached to the surface of the fiber due to the adhesiveness of the water-soluble polyphenol. Since water-soluble polyphenols act as antiallergen agents and antiviral agents by the protein denaturing action of phenol hydroxyl groups, they can not only fix functional agents but also impart antiallergen performance and antiviral performance to fiber sheets.

The water-insoluble antibacterial and / or antifungal agent is preferably an organic compound containing at least one of a nitrogen-containing heterocycle and a sulfur atom, and is a particulate matter. Specific examples thereof include organic antibacterial and antifungal agents such as benzimidazole compounds, pyrithione compounds and isothiazolinones, and among them, a combination of pyrithione compounds and benzimidazole compounds is preferable. In addition, iodine-based fungicides are also mentioned, and among them, diiodomethyl-p-trissulfone, 3-iodo-2-propynylbutylcarbamate and the like can be mentioned. The antibacterial and / or antifungal agent may be used alone or in combination of two or more.

Depending on the constituents of the flame retardants, the organic flame retardants such as phosphorus-based flame retardants, nitrogen-based flame retardants, halogen-based flame retardants, brominated flame retardants and their composites, and magnesium hydroxide, respectively, are organic compounds. It is roughly classified into inorganic flame retardants such as aluminum hydroxide, antimony, and silicone. The RoHS directive in Europe prohibits the use of some brominated flame retardants such as PBDE (polybrominated diphenyl ether) from the viewpoint of environmental load, and when polyvinyl alcohol components such as vinylon and cellulose components such as pulp burn. A phosphorus-based flame retardant is preferable from the viewpoint that it has a high effect of promoting carbonization and can promote carbonization and prevent it from spreading even if a fiber of a type that melts during combustion such as polyester fiber is mixed. Specific examples of the phosphorus-based flame retardant include phosphoric acid, phosphoric acid ester, ammonium phosphate, guanidine phosphate, melamine phosphate, guanylurea phosphate, and polycompounds of these compounds. The above flame retardants may be used alone or in combination of two or more.

The content of the functional agent is preferably 70 parts by mass or less with respect to 100 parts by mass of the water-soluble polyphenol. By setting the content of the drug to 70 parts by mass or less, it is possible to reduce the number of functional drugs that do not adhere to the water-soluble polyphenol and prevent them from falling off from the fiber sheet. Further, it is preferably 1 part by mass or more with respect to 100 parts by mass of the water-soluble polyphenol. When the content of the functional drug is 1 part by mass or more, the functionality of the functional drug can be sufficiently expressed.

When thiabendazole or zinc pyrithione, which are organic antibacterial and antifungal agents, are used as the functional agent in order to exhibit the effect of the functional agent, it is preferably contained in an amount of 0.1% by mass or more based on the mass of the fiber sheet. When diiodomethyl-p-trissulfone and 3-iodo-2-propynylbutylcarbamate, which are iodine-based fungicides, are used as functional agents, they are preferably contained in an amount of 1% by mass or more based on the mass of the fiber sheet. When melamine polyphosphite, which is a flame retardant, is used as a functional agent, it is preferably contained in an amount of 10% by mass or more based on the mass of the fiber sheet.

A preferred embodiment of the method for producing a fiber sheet of the present invention will be described in detail. In the fiber sheet of the present invention, a water-soluble polyphenol and a functional agent may be mixed with an aqueous solvent in the same bath to prepare a processing liquid, and the processing liquid may be impregnated into a base material or spray-coated, or the water-soluble polyphenol may be used. The processing liquid may be mixed with an aqueous solvent to prepare a processing liquid, and the processing liquid may be impregnated into a fiber sheet or spray-applied, and then the functional agent may be mixed with an aqueous solvent to prepare a processing liquid.

Here, the aqueous solvent includes water alone, lower alcohols such as methanol and ethanol, lower ketones such as acetone and methyl ethyl ketone, lower carboxylic acids such as acetic acid, and glycols such as ethylene glycol, propylene glycol and diethylene glycol. Examples thereof include an aqueous solution containing a water-soluble organic solvent, which can be selected according to the purpose.

The method of drying the fiber sheet coated with the processing liquid is not particularly limited, but a hot air drying method, a Yankee drum method, or the like is preferably adopted. The drying temperature is preferably 100 to 230 ° C, more preferably 110 to 160 ° C. By setting the drying temperature to 100 ° C. or higher, it can be dried in a short time, and by setting the drying temperature to 230 ° C. or lower, the decomposition of water-soluble polyphenols can be further suppressed.

The fiber sheet of the present invention can be suitably used for air filter applications, particularly as a filter for an air purifier or a cabin filter for an automobile. Antifungal, antibacterial, antiallergenic, flame-retardant, etc. are required due to increasing needs for comfort in interior spaces and consideration for safety. The above sheet is processed into a pleated shape and filtered. It can be preferably used as a unit. In order to obtain the retention of the pleated shape of the filter, it is more preferable to use a base material having a Gale stiffness and softness of 300 mg or more as the rigidity of the fiber sheet.

Further, in the filter using the fiber sheet of the present invention, it is preferable to laminate the fiber sheet and the melt blow nonwoven fabric from the viewpoint of providing the dust removing performance of the filter. Further, from the viewpoint of providing high dust removal performance and high air permeability, the melt blow nonwoven fabric is preferably charged. Further, when used as a filter for air purification, a melt blown nonwoven fabric having an average fiber diameter of 3 μm or less or the above melt blown nonwoven fabric subjected to electret processing is more preferable.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not necessarily limited thereto.

(1) Metsuke The mass of the evaluation sample (fiber sheet) is determined by leaving it at room temperature of 24 ° C. and 60% RH for 8 hours or more, and the mass is converted from the area to the mass per 1 m ² to obtain the basis weight of the evaluation sample. The minimum area of the evaluation sample was 0.01 m ² or more.

(2) Thickness The thickness was measured using a dial thickness gauge (TECLOCK SM-114 transducer shape 10 mmφ, scale 0.01 mm, measuring force 2.5 N or less). The measurement was performed by sampling 5 places arbitrarily from 1 sample, and the average value was used.

(3) Adhesion amount For the adhesion amount of water-soluble polyphenols and functional agents, first measure the basis weight of the fiber sheet before spray application and the basis weight of the fiber sheet after spray application drying treatment under the condition of (1), and determine the difference. Calculate the total amount of adhesion. Next, the adhesion amounts of both components can be calculated by multiplying the total adhesion amount by the solid content mass ratio of both substances.

(4) Allergen reduction rate The target allergens (sugi pollen allergen Cryj 1 and dania allergen Derf 2) were dissolved in phosphate buffer at 100 ng / ml to prepare each allergen solution.

Next, the fiber sheet was cut into 70 mg each, put into a microtube, 1 ml of the allergen solution was added to each, shaken at 4 ° C. for 5 hours, and allowed to stand for 20 hours for reaction. The allergen concentration of the allergen solution reacted with the sample was measured by the sandwich ELISA method. The sandwich ELISA method was performed according to the following procedure. Antibodies to the allergen (antigen) are immobilized in each well of the microplate. Then, wash with post-coating (1% BSA PBS) and PBS (including 0.05% Tween 20) three times (the washing method is the same below), and add a sample and a standard allergen. After washing, a labeled antibody against the allergen is added, and after washing, streptavidin HRPO is added. After washing, o-phenylenediamine is added, H ₂ SO ₄ is added, the reaction is stopped, and then the absorbance at 490 nm of the microplate reader is measured.

Separately, a calibration curve of absorbance-allergen concentration was prepared with a standard allergen solution, the allergen concentration was calculated, and the allergen reduction rate was calculated by the following formula.
Allergen reduction rate (%) = (BA) / B × 100
A: Allergen concentration in the allergen solution after the sample reaction B: Allergen concentration in the unreacted allergen solution of the sample Those with an allergen reduction rate of 98% or more were evaluated as "very excellent" and "◎" in Table 1. Notated with a mark. Those with 90% or more and less than 98% were evaluated as "excellent" and marked with "○" in Table 1. Those with 50% or more and less than 90% were evaluated as "slightly inferior" and marked with "Δ" in Table 1. Those with less than 50% were evaluated as "inferior" and marked with "x" in Table 1.

(5) Antifungal property In JIS Z2911 (2010) (mold resistance test (wet method)), hyphal growth is not observed in the inoculated part of the sample (display 0) or display 1 is "excellent". It was evaluated as "Yes" and marked with "○" in Table 1. Those with display 2 were evaluated as "inferior" and marked with "x" in Table 1.

(6) Powder removal A 12 cm × 12 cm square sample is cut from the fiber sheet, and the circumference of the sample is fixed to a 1 cm wide rigid frame so that a surface of 10 cm × 10 cm appears. Hold one side of this rigid frame on A3 size black paper with one hand, and tap the opposite side with the other hand to visually check the degree of powder falling.

[Example 1]
(Base fiber sheet)
ah. 30 parts by mass of polyester staple fibers (polyethylene terephthalate, melting point 265 ° C.) with a fineness of 16 dt with respect to 100 parts by mass of the base fiber sheet, a. 20 parts by mass of heat-fused polyester staple fibers with a fineness of 8 dt (core part: polyethylene terephthalate, melting point 265 ° C., sheath part: modified polyester, melting point 155 ° C.), c. Heat-fused polyester staple fibers with a fineness of 4.4 dt (core: polyethylene terephthalate, melting point 265 ° C, sheath: modified polyester, melting point 180 ° C) are mixed in 50 parts by mass and passed through a cotton opener and a carding machine. The web was spun out with a cloth wrap to obtain the desired mass, and the fabric was passed through an air-through heating furnace with a transport conveyor to obtain a thermal-bonded non-woven fabric having a grain size of 70 g / m ² and a thickness of 0.4 mm.
(Processing liquid)
Tannic acid (water-soluble polyphenol) and water were mixed to make processing liquid 1, and thiabendazole (water-insoluble antibacterial antifungal agent), zincpyrythion (water-insoluble antibacterial antifungal agent) and water were mixed to make processing liquid 2. .. The concentration of the processing liquid 1 was adjusted so that the amount of tannic acid adhered was 3 g / m ² . The concentration of the processing liquid 2 was adjusted so that the amount of thiabendazole adhered was 0.25 g / m ² and the amount of zinc pyrithione adhered was 0.25 g / m ² .
(Processing method)
After the processing liquid 1 was spray-applied to the base fiber sheet, the processing liquid 2 was spray-applied and dried at 110 ° C. to obtain a fiber sheet. Table 1 shows the fiber sheet formulation and the evaluation results. The obtained fiber sheet had a good allergen reduction rate. There was very little powder falling off and it was good.

[Example 2]
(Base fiber sheet)
The same thermal-bonded non-woven fabric as in Example 1 was used as the base fiber sheet.
(Processing liquid)
Tannic acid and water were mixed to prepare the processing liquid 3, and thiabendazole, zinc pyrithione and water were mixed to obtain the processing liquid 4. The concentration of the processing liquid 3 was adjusted so that the amount of tannic acid adhered was 10 g / m ² . The concentration of the processing liquid 4 was adjusted so that the amount of thiabendazole adhered was 0.5 g / m ² and the amount of zinc pyrithione adhered was 0.5 g / m ² .
(Processing method)
After spray-applying the processing liquid 3 to the base fiber sheet, the processing liquid 4 was spray-applied and dried at 110 ° C. to obtain a fiber sheet. Table 1 shows the fiber sheet formulation and the evaluation results. The obtained fiber sheet had a good allergen reduction rate. There was very little powder falling off and it was good.

[Example 3]
(Base fiber sheet)
The same thermal-bonded non-woven fabric as in Example 1 was used as the base fiber sheet.
(Processing liquid)
Tannic acid and water were mixed to obtain a processing liquid 5, and thiabendazole, zinc pyrithione and water were mixed to obtain a processing liquid 6. The concentration of the processing liquid 5 was adjusted so that the amount of tannic acid adhered was 30 g / m ² . The concentration of the processing liquid 6 was adjusted so that the amount of thiabendazole adhered was 0.25 g / m ² and the amount of zinc pyrithione adhered was 0.25 g / m ² .
(Processing method)
After spray-applying the processing liquid 5 to the base fiber sheet, the processing liquid 6 was spray-applied and dried at 110 ° C. to obtain a fiber sheet. Table 1 shows the fiber sheet formulation and the evaluation results. The obtained fiber sheet had a very good allergen reduction rate. There was very little powder falling off and it was good.

[Example 4]
(Base fiber sheet)
The same thermal-bonded non-woven fabric as in Example 1 was used as the base fiber sheet.
(Processing liquid)
Tannic acid and water were mixed to obtain a processing liquid 7, and thiabendazole and water were mixed to obtain a processing liquid 8. The concentration of the processing liquid 7 was adjusted so that the amount of tannic acid adhered was 3 g / m ² . The concentration of the processing liquid 8 was adjusted so that the amount of thiabendazole adhered was 0.025 g / m ² and the amount of zinc pyrithione adhered was 0.025 g / m ² .
(Processing method)
After spray-applying the processing liquid 7 to the base fiber sheet, the processing liquid 8 was spray-applied and dried at 110 ° C. to obtain a fiber sheet. Table 1 shows the fiber sheet formulation and the evaluation results. The obtained fiber sheet had a good allergen reduction rate. There was very little powder falling off and it was good.

[Example 5]
(Base fiber sheet)
The same thermal-bonded non-woven fabric as in Example 1 was used as the base fiber sheet.
(Processing liquid)
Tannic acid and water were mixed to obtain a processing liquid 9, and thiabendazole, zinc pyrithione and water were mixed to obtain a processing liquid 10. The concentration of the processing liquid 9 was adjusted so that the amount of tannic acid adhered was 0.5 g / m ² . The concentration of the processing liquid 10 was adjusted so that the amount of thiabendazole adhered was 0.7 g / m ² and the amount of zinc pyrithione adhered was 0.7 g / m ² .
(Processing method)
After spray-applying the processing liquid 9 to the base fiber sheet, the processing liquid 10 was spray-applied and dried at 110 ° C. to obtain a fiber sheet. Table 1 shows the fiber sheet formulation and the evaluation results. The obtained fiber sheet had a good allergen reduction rate and antifungal performance, but powder was slightly removed as compared with Example 1.

[Comparative Example 1]
(Base fiber sheet)
The same thermal-bonded non-woven fabric as in Example 1 was used as the base fiber sheet.
(Processing liquid)
Thiabendazole, zinc pyrithione, water and an acrylic binder were mixed to prepare a processing liquid 11. The concentration of the processing liquid 11 was adjusted so that the amount of thiabendazole adhered was 0.25 g / m ² , the amount of zinc pyrithione adhered was 0.25 g / m ² , and the amount of acrylic binder was 3 g / m ² .
(Processing method)
The processing liquid 11 was spray-coated on the base fiber sheet and dried at 110 ° C. to obtain a fiber sheet. Table 1 shows the fiber sheet formulation and the evaluation results. The obtained fiber sheet was inferior in allergen reduction rate as compared with Example 1.

The fiber sheet of the present invention can be suitably used for air filter applications, particularly as a filter for an air purifier or a cabin filter for an automobile.

Claims (3)

A sheet made of fibers, in which water-soluble polyphenols are attached to the surface of the fibers, and the water-soluble polyphenols attached to the surface of the fibers are treated with a water-insoluble antibacterial and / or antifungal agent and a flame retardant. A fiber sheet to which a functional agent composed of one or more selected from the group consisting of is attached. The fiber sheet according to claim 1, wherein the content of the functional agent is 70 parts by mass or less with respect to 100 parts by mass of the water-soluble polyphenol content. A filter using the fiber sheet according to claim 1 or 2.