JP2002235268A - Nonwoven fabric comprising powder fixed thereto, method for producing the same, and sheet material comprising the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a nonwoven fabric comprising a powder fixed thereto, scarcely causing falling off of even the powder having a small particle diameter and capable of exhibiting original functions of the powder, to provide a method for producing the nonwoven fabric, and to obtain a sheet material containing the nonwoven fabric comprising the powder fixed thereto. SOLUTION: This nonwoven fabric comprising the powder fixed thereto is formed from a powder-containing fiber web containing the powder and ultrafine short fibers having <=4 μm fiber diameter and <=3 mm fiber length in a dispersed state thereof and formed by a method other than a wet method. The method for producing the nonwoven fabric comprises a step for jetting an assembly of the ultrafine short fibers and the powder from a nozzle into a gas by the actions of compressed air, dividing the assembly into the ultrafine short fibers, and dispersing the ultrafine short fibers and the powder, a step for accumulating the dispersed ultrafine short fibers and powder and forming the powder-containing fiber web, and a step for binding the powder-containing fiber web.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-woven fabric to which powder is fixed, that is, a powder-fixed non-woven fabric, a method for producing the same, and a sheet material containing the same.

[0002]

2. Description of the Related Art As a fiber material to which powder is fixed, for example, JP-A-63-135550 describes a fiber material carrying a powdery binder. However,
This fiber material is a starting material for the production of a glass fiber reinforced plastic molded product. Since a fiber having a single fiber diameter of 5 to 20 μm and a length of 4 to 25 mm is used as glass fiber, it has a small particle size. Powder is easily detached when subjected to vibration or impact, and cannot be firmly fixed. Japanese Patent Application Laid-Open No. 7-313863 discloses an air for mixing a reinforcing fiber and a powdery resin by using a gas flow in producing a preform at a stage before molding a fiber-reinforced plastic molded product. A mixing method is described. However, it is clear that the reinforcing fibers used in this method are thick and long, and have the same disadvantages as described above.

As a method of fixing powder to a nonwoven fabric, for example, a method of sandwiching the powder with a fiber web and then physically confining the powder between fibers with a needle punch or the like, or further fixing the powder. In order to enhance the properties, a method has been known in which a powder is sandwiched between fiber webs containing heat-bonded fibers, and then the powder is bonded to the fibers or the fibers by heat treatment. However, a powder having a small particle size having an average particle size of 50 μm or less is easily detached when subjected to vibration or impact, and only a relatively large powder having an average particle size exceeding 50 μm can be fixed. There was a drawback. On the other hand, as a method of improving the retention of powder having a small particle diameter of 50 μm or less by giving a finer structure to the fiber web, a method of shaving the powder together with the fiber by a wet method is used. It has been known. However, since surfactants and sizing agents are added to the slurry used in this wet method, these surfactants and sizing agents cover the surface of the powder, and the original function of the powder is lost. There was a disadvantage that it was easy.

[0004]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present inventor has found that even a powder having a small particle diameter is difficult to fall off and exhibits the original function of the powder. As a result of intensive research aimed at developing a powder-bonded nonwoven fabric and a method of manufacturing the same, in order to prevent the powder from losing its original function, a fiber web formed by a method other than the wet method is used. In order to prevent the necessity, and to prevent the powder from falling off the nonwoven fabric, ultrafine short fibers having a certain thickness or less and a certain length or less are dispersed, and the ultrafine short fibers are present around the powder (preferably. Has been found to be able to solve the above problem by reducing the space between the ultrafine short fibers by entangled in a spider web shape. The present invention is based on these findings.

[0005]

Accordingly, the present invention is formed by a method other than the wet method, comprising a dispersed state of powder and ultrafine short fibers having a fiber diameter of 4 μm or less and a fiber length of 3 mm or less. The present invention relates to a powder-bonded nonwoven fabric formed from a powder-containing fiber web.

In the powder-bonded nonwoven fabric, when the average particle size of the powder is 50 μm or less, the function of the powder can be maximized. Further, the mass ratio of the ultrafine short fibers to the total mass of the powder-bonded nonwoven fabric is 1 to 40 ma.
When the content is ss%, the amount of the powder is large, so that the function of the powder can be maximized. Further, when the adhesion rate of the deposit is 0.5 mass% or less, the function of the powder is not hindered by the deposit.

The inventor of the present invention has proposed a method for preparing an aggregate of ultrafine short fibers or an aggregate thereof, and / or a splittable fiber capable of mechanically dividing to generate ultrafine short fibers, or an aggregate thereof. When the compressed gas is ejected from the nozzle into the gas together with the body, the aggregate of the ultrafine short fibers or the aggregate group thereof, and / or a division capable of mechanically generating the ultrafine short fibers In addition to the fact that the conductive fibers or their aggregates are spread and dispersed, the dispersion of the powders has also progressed, and it has been found that the ultrafine short fibers entangle the individual powders in a spider web shape.

Accordingly, the present invention provides an aggregate of ultra-short fibers having a fiber diameter of 4 μm or less and a fiber length of 3 mm or less, or a group thereof, and / or a mechanically divided fiber having a fiber diameter of 4 μm or less. Splitting fibers capable of generating ultra-short fibers having a fiber length of 3 mm or less, or an aggregate thereof, together with powder, is ejected from a nozzle into a gas by the action of a compressed gas to produce the ultra-short fiber aggregates or a mixture thereof. Dividing the aggregate group into ultra-fine short fibers, and / or dividing the splittable fibers or their aggregates into ultra-fine short fibers and dispersing the powder, accumulating the dispersed ultra-fine short fibers and the powder. Forming a non-woven fabric from the obtained powder-containing fiber web, and fixing a powder contained in the powder-containing fiber web when forming a nonwoven fabric from the obtained powder-containing fiber web. Especially The present invention also relates to a method for producing a powder-bonded nonwoven fabric, which is a feature of the present invention.

Further, the present invention provides a method for producing a powder having a fiber diameter of 4 μm
At least one layer of a powder-bonded non-woven fabric formed from a powder-containing fiber web formed by a method other than the wet method, including a state in which ultrafine short fibers having a fiber length of 3 mm or less are dispersed.
It also relates to a sheet material, characterized in that it contains a layer. The sheet material may further include a powder-free layer (powder-free layer) on at least one surface of the powder-fixed nonwoven fabric layer, for example, a powder falling-off prevention layer. It is possible to more reliably prevent the powder from falling off.

Furthermore, the present invention provides an aggregate of ultra-fine short fibers having a fiber diameter of 4 μm or less and a fiber length of 3 mm or less, or a group thereof, and / or a mechanically divided fiber diameter of 4 μm or less. The fiber length is 3 mm or less The splittable fiber capable of generating ultra-short fibers or an aggregate thereof, together with the powder, is ejected from a nozzle into a gas by the action of a compressed gas, the ultra-short fiber aggregate or A step of dividing the aggregate group into ultrafine short fibers and / or dividing the splittable fibers or their aggregates into ultrafine short fibers and dispersing the powder, and accumulating the dispersed ultrafine short fibers and powder Step of forming a powder-containing fiber web, and, when forming a nonwoven fabric from the obtained powder-containing fiber web, to fix the powder contained in the powder-containing fiber web,
Further, the present invention relates to a method for producing a sheet material containing a powder-bonded nonwoven fabric layer, which comprises a step of bonding a layer containing no powder at the same time.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The powder-bonded nonwoven fabric of the present invention contains ultrafine short fibers having a fiber diameter of 4 μm or less so as to have excellent powder holding properties. The smaller the fiber diameter of the ultrafine short fiber, the better the powder holding property and the smaller the diameter of the powder can be held. Therefore, the fiber diameter of the ultrafine short fiber is preferably 3 μm or less, more preferably 2 μm or less. More preferably, there is. In addition, the lower limit of the fiber diameter of the ultrafine short fibers is not particularly limited, but about 0.01 μm is appropriate. The `` fiber diameter '' in this specification refers to the diameter of the fiber when the cross-sectional shape is circular, and the diameter of the same cross-sectional area and area when the cross-sectional shape of the fiber is non-circular. Say.

The ultra-fine short fibers constituting the powder-bonded nonwoven fabric of the present invention have a fiber length of 3 so as to have excellent uniform dispersibility.
mm or less. That is, if the fiber length is more than 3 mm, the dispersibility is reduced because the degree of freedom of the ultrafine fiber is low. A more preferable fiber length is 2 mm or less. The lower limit of the fiber length of the ultrafine short fibers is not particularly limited, but is preferably about 0.1 mm. Further, it is preferable that the fibers are ultrafine short fibers cut into a fiber length of 3 mm or less so that the fiber length is uniform. The “fiber length” in this specification refers to a length obtained by JIS L 1015 (chemical fiber staple test method) B method (corrected staple diagram method).

The ultra-short fibers used in the present invention can be composed of any component (for example, an organic component or an inorganic component). Vinyl resin, polyester resin, polyacrylonitrile resin, polyolefin resin (eg, polyethylene resin, polypropylene resin, etc.), polystyrene resin (eg, crystalline polystyrene, amorphous polystyrene, etc.), wholly aromatic polyamide Resin, organic components such as polyurethane resin, glass, carbon, potassium titanate,
Silicon carbide, silicon nitride, zinc oxide, aluminum borate,
It can be composed of inorganic components such as wollastonite.

In general, when the ultrafine short fibers are composed of an organic component, the rigidity is lower and softer than when the ultrafine fibers are composed of an inorganic component. Although it is difficult to obtain the advantage of containing ultrafine short fibers, in the powder-fixed nonwoven fabric of the present invention, since the ultrafine short fibers are uniformly dispersed, the ultrafine short fibers are made of an organic component. (For example, bulkiness, texture, or elasticity) can be improved.

The fibers are preferably bonded to each other in order to maintain the non-woven form of the powder-fixed non-woven fabric according to the present invention. This is preferable because the nonwoven fabric can be kept in a non-woven form, and the ultrafine short fibers and the powder hardly fall off. It is preferable that at least a part of the component constituting the surface of the ultrafine short fiber is made of a thermoplastic resin. For example, the component constituting the ultrafine short fiber surface,
Polyolefin resin (for example, polyethylene resin,
A crystalline thermoplastic resin such as a polyvinylidene chloride resin, a polyester resin, a polyamide resin, a crystalline polystyrene resin, or a polyvinyl chloride resin, an amorphous polystyrene resin,
It can be an amorphous thermoplastic resin such as a polyacrylonitrile resin, a polyvinyl alcohol resin, or a polyvinyl acetate resin. Among these, a polyethylene resin having a relatively low melting point and a polyvinyl acetate resin having a relatively low melting point are preferable. Note that inorganic fibers such as glass fibers and metal fibers such as copper fibers can also be used.

If the fusible ultrafine short fiber is composed of two or more components, the fiber form can be maintained by at least one component even if one component is fused. It is suitable. The cross-sectional shape of the ultrafine short fiber which can be fused when composed of two or more kinds of components is, for example, a core-sheath type, an eccentric type, a sea-island type, a side-by-side type, a multiple bimetal type, and an orange type. be able to.

In the ultrafine short fibers used in the present invention, the diameter of each ultrafine short fiber does not substantially change in the fiber axis direction (ie, substantially the same) so that the texture of the powder-bonded nonwoven fabric is excellent. Having a diameter).
As described above, the ultra-fine short fibers whose diameters are substantially the same in the fiber axis direction and do not change in the individual ultra-fine short fibers are, for example, extruded into the sea component at the spinneret to extrude the island component to form a composite. It can be obtained by removing the sea component of the sea-island type fiber obtained by the composite spinning method. Generally, when forming the ultrafine short fibers by removing the sea component of the sea-island type fiber, each ultrafine short fiber derived from the island component exists as a bundle and the ultrafine short fibers are mutually connected. It is difficult to obtain the advantage of containing ultrafine short fibers because it is easy to entangle because of being close, and it is difficult to uniformly disperse. Even if the ultra-fine short fiber aggregate is used, the ultra-fine short fibers are not present in a bundle,
Since they can be dispersed uniformly, the advantage of containing ultra-short fibers can be obtained. In addition, bundles of ultrafine short fiber aggregates formed by removing sea components from sea-island fibers are generally easily aggregated, and thus difficult to disperse, but can be dispersed in the present invention.
The advantage of containing ultrafine short fibers can be obtained.

The ultrafine short fiber used in the present invention may be in an undrawn state, but is preferably in a drawn state so as to be excellent in strength.

In the powder-bonded nonwoven fabric of the present invention, the powder is fixed to the fiber web in which the ultrafine short fibers are dispersed as described above. be able to. Since the fiber web is formed by a method other than the wet method, the powder is not coated with a surfactant or a sizing agent as in the case of the fiber web formed by the wet method. Function can be exhibited. The method other than the wet method, that is, the method other than the wet method, is not particularly limited as long as it is different from the method of dispersing ultrafine short fibers and powder using a slurry containing a surfactant and / or a sizing agent. Although not limited thereto, for example, a method of forming a fiber web using gas as a dispersion medium can be used. In particular, a method is preferred in which ultrafine short fibers dispersed in a gas are deposited and then fixed by an appropriate fixing method (for example, a heat fusion method).

The powder used in the present invention may be an organic powder, an inorganic powder, a metal powder, or a composite powder of an organic substance and an inorganic substance (for example, an organic resin-coated inorganic powder). Instead, it can be appropriately selected according to the application to which the powder-fixed nonwoven fabric is applied. For example, when the powder-bonded nonwoven fabric is used for decomposing ozone, activated carbon or the like can be used as the powder,
When using powder-bonded nonwoven fabric for ion exchange applications,
When ion-exchange resin powder or the like can be used, and when the powder-bonded nonwoven fabric is used for a catalyst, a catalyst powder such as manganese dioxide, platinum, or titanium oxide can be used. When used for deodorizing or deodorizing purposes, deodorant powder or deodorant powder can be used, and the powder-bonded nonwoven fabric can be replaced with fiber reinforced plastic (FRP) or sheet prepreg (sheet mol
When used for applications such as ding compound (SMC), a heat-adhesive resin powder or the like can be used, and the powder-bonded nonwoven fabric is used for applications such as fiber-reinforced plastic (overlay) such as a ship or bathtub. In such a case, a thermosetting resin powder or the like can be used.
An inorganic powder or the like can be used.

As the powder, for example, heat-fusible resin powder (for example, polypropylene, polyethylene, etc.),
Thermosetting resin powders (eg, thermosetting polyethylene terephthalate, phenolic resin), inorganic powders (eg, glass), and metal powders (eg, zinc, aluminum, tin, etc.) include these powders. Is preferable since the powder can be firmly fixed to the powder-fixed non-woven fabric by the adhesive action of.

Further, if the heat-fusing resin is included as a part of the surface of the powder itself, the powder can be securely fixed to the powder-fixing nonwoven fabric by the heat-fusing resin.
This is one of preferred embodiments.

In the powder-bonded nonwoven fabric of the present invention, since the ultrafine short fibers as described above are used, even if the average particle diameter of the powder is 50 μm or less which has conventionally been easy to fall off, it does not fall off. Can be held. Since this powder is mainly held by the ultrafine short fibers, the powder that can be held varies depending on the fiber diameter of the ultrafine short fibers. That is, in the powder-bonded nonwoven fabric of the present invention, an ultrafine short fiber having an appropriate fiber diameter can be selected according to the average particle size of the powder to be held. For example, Table 1 shows the relationship between the fiber diameter of the ultrafine short fibers and the average particle diameter of the optimum powder.

[0024]

[Table 1]

Incidentally, even if the average particle diameter of the powder exceeds 50 μm, the powder can be held by the fiber web as described above. `` Average particle size '' of the powder in the present invention,
A value obtained by the Coulter counter method.

Since such a powder is fixed by the fiber web as described above, the powder does not fall off from the powder-fixed nonwoven fabric. The "fixed state" means a state in which the powder is fixed, for example, a state in which the powder is fixed by the fact that the ultrafine fibers mainly surround the powder, the ultrafine fibers, And / or a state in which the powder is fixed by fusion of thick fibers described later, or a state in which the powder is fixed by a plurality of factors.

In the powder-bonded nonwoven fabric according to the present invention, the mass ratio of the ultrafine short fibers as described above is determined by determining the average particle size of the powder,
It depends on the specific gravity or the fiber diameter of ultra-fine short fibers,
If it is 40 mass% or less, even if the powder has a small average particle diameter of about 50 μm or less, the powder can be held so as not to fall off. Can do 10mas
A powder-bonded nonwoven fabric having no problem in practical use at s% or less and no problem in practical strength in handling can be obtained. On the other hand, if the mass ratio of the ultrafine short fibers is 1 mass% or more, the powder hardly falls off and has practical handling strength.

In the powder-bonded nonwoven fabric of the present invention, at least the ultrafine short fibers as described above are dispersed.
The effect by including the ultrafine short fiber can be exhibited. The content of the ultrafine short fibers in the constituent fibers of the powder-fixed nonwoven fabric is preferably 20 mass% or more, and more preferably 50 mass% or more so that the effect of including the ultrafine short fibers can be exerted. Is more preferable, and 100 mass% is most preferable.

In the powder-bonded nonwoven fabric of the present invention, as the fibers other than the ultra-short fibers, (1) a fiber diameter of 4 μm
(2) fibers having a fiber diameter of 4 μm or less but having a fiber length of more than 3 mm (hereinafter referred to as long fibers), or (3) Fiber diameter exceeds 4μm and fiber length is 3mm
(Hereinafter, referred to as a long fiber). Among these, long fibers having a fiber length of more than 3 mm and thick fibers have poor dispersibility, which may impair the dispersibility of ultrafine short fibers. Therefore, it is preferable to use thick fibers having a fiber length of 3 mm or less.

When the above-mentioned thick fiber is used, the upper limit of the fiber diameter is not particularly limited, but if the difference in fiber diameter from the ultra-fine short fiber is too large, the formation of the powder-bonded nonwoven fabric may be impaired. For this reason, the upper limit of the fiber diameter of the thick fiber is preferably about 50 μm. It is preferable that the thickness of the thick fiber is 2 mm or less so that the dispersibility is also excellent. Although the lower limit is not particularly limited, about 0.1 mm is appropriate. Also, so that the thick fibers are also of uniform length,
It is preferably cut into a length of 3 mm or less.

This thick fiber can be composed of the same components as the ultrafine short fiber. That is, for example, polyamide resin, polyvinyl alcohol resin, polyvinylidene chloride resin, polyvinyl chloride resin, polyester resin, polyacrylonitrile resin, polyolefin resin (for example, polyethylene resin, polypropylene resin, etc.), Polystyrene resin (crystalline polystyrene,
Organic components such as amorphous polystyrene), wholly aromatic polyamide resins and polyurethane resins, and inorganic components such as glass, carbon, potassium titanate, silicon carbide, silicon nitride, zinc oxide, aluminum borate, wollastonite Can be composed of

When the above-mentioned thick fiber can be fused, the non-woven fabric form of the powder-fixed nonwoven fabric according to the present invention can be maintained by fusing the thick fiber. In this fusible thick fiber, at least a part of the component constituting the thick fiber surface can be formed of a thermoplastic resin. For example, the component constituting the surface of the thick fiber is made of a crystalline material such as a polyolefin resin (for example, a polyethylene resin or a polypropylene resin), a polyvinylidene chloride resin, a polyester resin, a polyamide resin, or a crystalline polystyrene resin. Or an amorphous thermoplastic resin such as a polyvinyl chloride resin, an amorphous polystyrene resin, a polyacrylonitrile resin, or a polyvinyl alcohol resin. Among these, a polyethylene resin having a relatively low melting point and a polyvinyl acetate resin having a relatively low melting point are preferable. Note that inorganic fibers such as glass fibers and metal fibers such as copper fibers can also be used.

When the fusible thick fiber is composed of two or more components having different melting points, even if one component is fused, the fiber form is maintained by at least one other component. This is preferable because it can be performed. When the fusible thick fiber is composed of two or more types of components, the cross-sectional shape of the fusible thick fiber is, for example, a core-sheath type, an eccentric type, a sea-island type, a side-by-side type, a multiple bimetal type. Or orange type. The thick fiber may be in an undrawn state, but is preferably in a drawn state so as to be excellent in strength.

The adhering rate of adhering substances (surfactants, sizing agents, etc.) adhering to the powder-bonded nonwoven fabric of the present invention is 0.5
It is preferably at most mass%. Since the smaller the adhesion rate of the deposit is, the less the function of the powder is impaired, the adhesion rate is preferably 0.3 mass% or less, more preferably 0.1 mass% or less, and still more preferably 0.08 mass%. Below, even more preferably 0.06
mass% or less, still more preferably 0.04 mass
% Or less, still more preferably 0.02 mass% or less. Such a low deposition rate of the deposits is a level that cannot be obtained by the conventional wet method. Even if a water stream is applied to a wet fiber web (including powder) to which a surfactant or a sizing agent is attached, it is difficult to reduce the attachment rate of the attached matter to 0.5 mass% or less. is there.

In the powder-bonded nonwoven fabric of the present invention,
If the adhesion rate of the deposits is low, various favorable effects are brought about because the risk of detachment of the deposits during use of the powder-fixed nonwoven fabric is extremely low. For example, generally, when a normal nonwoven fabric is used as a filter, even if dust contained in the fluid before filtration can be physically removed by the filter, the filter (nonwoven fabric) itself can remove contaminants. If it occurs, its role as a filter will be reduced by half. On the other hand, the powder-fixed nonwoven fabric of the present invention or the sheet material according to the present invention containing at least one layer of the powder-fixed nonwoven fabric has a small amount of deposits, and the possibility of detachment of the deposits is extremely low. Therefore, it can be suitably used as a filter.

The adhesion rate of the deposit refers to the percentage of the mass of the deposit relative to the mass of the powder-fixed nonwoven fabric. That is,
The following equation (1): A = (ms / mf) × 100 (1) [where A is the adhesion rate (%) of the attached matter, ms is the attached mass of the attached matter (g), and mf is the powder adhesion. Nonwoven fabric mass (g)
, Respectively.] The term “adhered matter” in this specification refers to an extract obtained by immersing the powder-fixed nonwoven fabric in hot water (for example, water at 80 to 100 ° C.) for 15 minutes (hereinafter, referred to as a hot water extract). ) And the powder-bonded nonwoven fabric in hot methanol solution
Both extracts obtained by soaking for 5 minutes (hereinafter referred to as hot methanol extracts) are included. The hot water extract includes a paste (eg, acrylamide, sodium polyacrylate, sodium polyalginate, polyethylene oxide, methylcellulose, carboxymethylcellulose, hydroxymethylcellulose, polyvinyl alcohol, etc.), and the hot methanol extract includes a surfactant ( Compounds having both hydrophilic and lipophilic groups, for example,
Nonionic surfactants).

The powder-fixing nonwoven fabric of the present invention preferably has fibers (ultrafine short fibers, thick fibers, etc.) and / or powder constituting the nonwoven fabric fused. This is because the powder is less likely to fall off due to this fusion.

The powder-bonded nonwoven fabric of the present invention does not need to be a single layer.
It can contain more than one layer. When two or more layers in which the powder is fixed and the ultra-fine short fibers are dispersed are provided, various characteristics can be imparted. For example, a powder-bonded nonwoven fabric having a powder-fixed nonwoven fabric layer to which an ion exchange resin powder is fixed and a powder-fixed nonwoven fabric layer to which a deodorant powder is fixed has both ion exchange performance and deodorization performance. is there.

Although the powder-fixed nonwoven fabric of the present invention is composed of only the powder-fixed nonwoven fabric layer to which the powder is fixed as described above, it is sufficiently practical that the powder does not easily fall off.
If a small amount of powder is not allowed to fall off, a powder-free layer is placed on the surface (at least one side) of the powder-bonded non-woven fabric layer to which the powder is fixed as described above, where the powder must not fall off. For example, it is preferable to further include a falling-off prevention layer capable of preventing the powder from falling off.

The falling-off preventing layer is not particularly limited as long as it has a function of preventing powder falling-off, but the fiber diameter is the same as or smaller than that of the ultrafine short fibers constituting the powder-fixing nonwoven fabric layer. Also, it is preferable that the nonwoven fabric is derived from a fiber web containing ultrafine short fibers having a small fiber diameter (that is, a fiber diameter of 4 μm or less). However, the fiber diameter also varies depending on the average particle diameter of the fixed powder. This non-woven fabric
For example, the nonwoven fabric is maintained by the fusion of ultrafine short fibers. Such a nonwoven fabric can be produced, for example, by a method that does not supply a powder when forming a powder-fixed nonwoven fabric layer as described below, or by forming an ultrafine short fiber into a fiber web by a normal wet method. After that, utilizing the fusibility of ultra-fine short fibers, entangled by fluid flow such as water flow,
Alternatively, they can be produced by using these in combination.

Depending on the average particle size of the powder, a nonwoven fabric obtained by a melt blowing method or a fiber web containing fibers which can be mechanically split is formed by a dry method or a wet method, and then formed by a fluid flow such as a water flow. An entangled nonwoven fabric or the like can be used as the falling-off prevention layer.

The basis weight of the fall-prevention layer is not particularly limited since it varies depending on the fiber, structure, average particle size of the powder and the like constituting the fall-prevention layer, but the basis weight is 1 g / m ^2.
If it is above, it can become a fall prevention layer which has no problem practically.

Since the powder-bonded nonwoven fabric of the present invention is excellent in various properties due to containing ultra-fine short fibers and powder, it can be in the form of the powder-fixed nonwoven fabric of the present invention or the powder-bonded nonwoven fabric. In the form of a sheet material containing at least one layer, for example, an ozone decomposing sheet for an electrophotographic device, a toilet deodorizing device, or an ozone generator device; an ion exchange sheet such as an ion exchange water purifier; Or deodorizing or deodorizing sheets for household products, sanitary products, filters, or shoes; fiber reinforced plastic (FRP) or sheet prepreg (SMC); or fire resistant It can be used for various applications such as boards.

The powder-bonded nonwoven fabric of the present invention can be produced, for example, by the following method. First, an aggregate (particularly, a bundle-like aggregate) of the above powder and ultrafine short fibers having a fiber diameter of 4 μm or less and a fiber length of 3 mm or less, or a group thereof (particularly, a plurality of bundles). An aggregate group including the aggregate in a bundle) and / or a mechanically divided fiber diameter of 4μ.
A splittable fiber capable of generating ultra-fine short fibers having a fiber length of 3 mm or less with a length of m or less, or an aggregate thereof (particularly, a bundle-like aggregate) is prepared. In addition, as the ultra-fine short fiber aggregate or an aggregate group thereof, and / or the ultra-fine short fiber-generating splittable fiber or an aggregate thereof, the adhesion rate of a deposit (a surfactant, a glue, or the like) is low. 0.5mas
s% or less (preferably 0.3 mass% or less, more preferably 0.1 mass% or less, and still more preferably 0.1 mass% or less.
08 mass% or less, still more preferably 0.06 ma
ss% or less, still more preferably 0.04 mass% or less, even more preferably 0.02 mass% or less) the ultrafine short fiber aggregate or an aggregate group thereof, and / or
Alternatively, the use of splittable fibers capable of generating ultrafine short fibers or an aggregate thereof facilitates production of the powder-fixed nonwoven fabric of the present invention.

The ultra-short short fiber aggregate having a small adhesion rate of the deposits, the aggregate group thereof, or the ultra-short fiber-producing splittable fiber or the aggregate thereof has, for example, a fiber diameter of 4 μm or less and a fiber length of 4 μm. After preparing a commercially available ultra-short fiber aggregate or an aggregate group thereof having a diameter of 3 mm or less, or an ultra-fine short fiber-generating splittable fiber or an aggregate thereof, the adhering rate of the adhered substance is reduced to 0 by a solvent such as acetone. .
It can be obtained by washing until it becomes 5 mass% or less. Alternatively, an ultrafine short fiber aggregate having a low attachment rate of the deposits or a group of the aggregates is, for example, extracting and removing the sea component of a group of sea-island fibers or a group of sea-island fibers manufactured by a conjugate spinning method or a mixed spinning method. Can be obtained. Also,
If the sea component is extracted and removed from the sea-island fiber and then washed with a solvent such as acetone, the amount of deposits can be further reduced. In addition, when the attached matter is removed, static electricity is easily generated on the surface of the ultrafine short fibers, and the ultrafine short fibers are easily repelled and dispersed easily.

When the ultrafine short fiber aggregates or the ultrafine short fibers in the group of the aggregates are in an entangled state, the ultrafine short fibers can be uniformly dispersed even by the action of a compressed gas as described later. It is preferable that the ultrafine short fiber aggregates or the ultrafine short fibers in the group of the aggregates are not entangled because they tend to be difficult or require the compressed gas to act many times. For example, ultrafine short fiber aggregates obtained by beating beaten dividable fibers mechanically by a beater, pulp beaten by a beater or the like, or ultrafine short fiber aggregates obtained by flash spinning, etc. It is preferable not to use it because the fibers are entangled with each other. It should be noted that ultrafine short fiber-generating splittable fibers capable of generating ultrafine short fibers having a fiber diameter of 4 μm or less and a fiber length of 3 mm or less by mechanically dividing by the action of a compressed gas or an aggregate thereof (for example, Aromatic polyamide short fibers or aggregates thereof, cellulose short fibers obtained by solvent extraction or aggregates thereof)
Can be used. Also in the case of using the above-mentioned thick fiber or an aggregate thereof, it is preferable that washing with acetone or the like is performed in advance so as to reduce the adhered substance adhesion rate.

Next, the above-mentioned ultra-fine short fiber aggregate or an aggregate group thereof, and / or an ultra-fine short fiber-generating splittable fiber or an aggregate thereof (in some cases, a thick fiber or an aggregate thereof) ) Is supplied to the nozzle together with the powder as described above, and the compressed gas is applied thereto to cause the gas to be ejected from the nozzle into the gas. It splits into short fibers, disperses the ultrafine short fibers, and / or generates ultrafine short fibers from the splittable fibers capable of generating ultrafine short fibers or aggregates thereof, and disperses the ultrafine short fibers. When thick fibers or an aggregate thereof are included, the thick fibers are dispersed, or the thick fibers are separated from the aggregate and dispersed. Along with their dispersion, the above-mentioned powder is also dispersed at the same time.

It is preferable that the gas flow supplied to the nozzle is substantially laminar. In the case of a laminar flow, entanglement between the ultrafine short fibers does not easily occur, so that the ultrafine short fibers are easily dispersed. Generally, the fiber diameter of the fiber passing through the nozzle is 4μ.
m or less (especially 2 μm or less) and low rigidity (soft), bundles of ultrafine short fiber aggregates or aggregates thereof (especially bundles of ultrafine short fibers derived from island components of sea-island type fibers) In the case of a fiber aggregate or a group thereof, or when the ultrafine short fibers are made of an organic component and have low rigidity (softness), they tend to be entangled. However, even in such a case, the entanglement can be suppressed by making the flow of the gas supplied to the nozzle substantially laminar. By using a Venturi tube as a nozzle, the flow of gas passing through the nozzle can be made substantially laminar.

The nozzle may have a constant cross-sectional area from the supply side of the powder and the ultrafine short fiber aggregate or the like toward the ejection side (in the flow direction). That the cross-sectional area decreases or increases continuously or discontinuously in the flow direction also changes such that the cross-sectional area increases continuously or discontinuously in the flow direction and then decreases. Alternatively, the cross-sectional area may change continuously or discontinuously in the flow direction so that it decreases and then increases.
In addition, the powder ejected from the nozzle outlet, and a bundle of ultrafine short fiber aggregates (or a group thereof) and / or ultrafine short fiber-generating fibers (or an aggregate thereof), The powder, a bundle of ultrafine short fibers or a group thereof and / or a group of these ultrafine short fibers that can collide with a collision member (e.g., a baffle plate) provided in front of the nozzle injection port and can generate ultrafine short fibers It is possible to improve the generation efficiency of the ultrafine short fibers from the fibers (or an aggregate thereof) and the dispersion efficiency of the generated ultrafine short fibers. In particular, when the flow of the gas supplied to the nozzle is substantially laminar, the effect of dividing and dispersing the powder and the ultrafine short fibers is poor. Therefore, a collision member (for example, a baffle plate) is provided for dispersion. It is preferred to promote.

As the compressed gas, any gas can be used, and the use of air is preferable for the production of the powder-fixed nonwoven fabric. Further, the compressed gas can disperse the powder and sufficiently disperse the ultrafine short fiber aggregate or the aggregate thereof, and / or the ultrafine short fiber-generating splittable fiber or the aggregate thereof. Is preferably 100 m / sec or more at the nozzle outlet so that the fine particles can be divided into ultrafine short fibers and sufficiently dispersed. This “gas passage speed” is the flow rate (m ³ / sec) of the gas ejected from the nozzle at one atmosphere.
c) is divided by the cross-sectional area (m ² ) at the nozzle outlet. In addition, the pressure of the compressed gas disperses the powder, sufficiently disperses the ultrafine short fiber aggregate or the aggregate thereof, and / or disperses the ultrafine short fiber-generating splittable fiber or the aggregate thereof. 2kg / c so that it can be split into short fibers and sufficiently dispersed
It is preferably at least m ² .

Further, while dispersing the powder ejected from the nozzle, the ultra-fine short fiber aggregate or a group thereof is divided into ultra-fine short fibers and sufficiently dispersed, and / or
Alternatively, the gas as a dispersion medium for dividing the ultrafine fiber-producing splittable fibers or aggregates thereof into ultrafine fibers and dispersing them sufficiently is not particularly limited, but air is powder-fixed. It is suitable for the production of nonwoven fabric.

If the rate of adhesion of the extra-fine short fiber aggregates or the aggregates thereof and / or the ultra-short fiber-producible splittable fibers or the aggregates thereof is low, the nozzle and the aggregate may not be connected to each other. The effect is that static electricity is easily generated due to friction, and the ultrafine fibers repel each other and can be accumulated in a more dispersed state.

Next, the dispersed powder and the dispersed ultra-fine short fibers (including dispersed thick fibers in some cases) are accumulated to form a powder-containing fiber web. The accumulation of the powder and the ultrafine fibers can be carried out, for example, using a support such as a porous roll or a net. The powder and the ultrafine fibers can be dropped and accumulated, or can be accumulated by sucking a gas from below the support. In the latter case, when the suction force is increased, the powder-containing fiber web in a state where the powder and the ultrafine short fibers are in close contact with each other can be obtained. be able to.

In the present invention, the mass ratio of the ultrafine short fibers to the total mass of the powder-containing fiber web is from 1 to 1.
Since the content can be set to 40 mass%, the amount of the powder is large, and the function of the powder can be sufficiently exhibited. Such adjustment of the amounts of the ultrafine short fibers and the powder is performed by supplying the powder and the ultrafine short fiber aggregate or a group thereof and / or the splittable fibers capable of generating the ultrafine short fiber or the aggregate thereof to the nozzle. It can be carried out by adjusting the amount.

Next, the powder contained in the powder-containing fiber web is fixed to produce the powder-fixed nonwoven fabric of the present invention. The fixing method is not particularly limited, and examples thereof include a method of fusing fibers (extremely short fibers and / or thick fibers) and / or powder.

The above is a basic method for producing the powder-fixed nonwoven fabric of the present invention. Before the aggregate group and / or the aggregate of the ultra-short fiber-generating splittable fibers are jetted out of the nozzle into the gas by the action of the compressed gas, the number of the ultra-fine short fiber aggregates using a mixer or the like is reduced. It is preferable to subdivide, disperse, or mix an aggregate of (or an aggregate group) and / or a smaller number of ultrafine short fiber-generating splittable fibers.

After forming the powder-containing fiber web,
Before fixing the powder, the powder-containing fiber web is supplied again to the same or a different nozzle, and the powder and ultra-short fibers are ejected from the nozzle into the gas to be re-dispersed to form the powder-containing fiber web. Can be repeated.

In order to obtain a powder-bonded nonwoven fabric containing two or more types of ultra-short fibers and / or thick fibers which differ in the fiber diameter, the ultra-fine short fiber aggregate or a group thereof, Alternatively, an ultrafine short fiber-generating splittable fiber or an aggregate thereof, and / or a thick fiber aggregate can be used in combination. Further, a fiber aggregate containing ultra-fine short fibers having different fiber diameters or a group thereof, a splittable fiber capable of generating ultra-fine short fibers having a different fiber diameter or an aggregate thereof and / or a fiber diameter It is also possible to supply the nozzles while changing the blending amounts of the thick fibers or the aggregates thereof, which are different from each other, continuously or discontinuously. With such a change, the layer or region having a different apparent density due to the difference in fiber diameter,
A powder-bonded nonwoven fabric having a thickness direction can be manufactured. Further, the compounding amount of two or more kinds of powders differing in average particle size and / or composition may be supplied to the nozzle while changing continuously or discontinuously.

The powder-bonded nonwoven fabric provided with the above-mentioned suitable falling-off preventing layer, or the sheet material of the present invention comprising the powder-fixing nonwoven fabric layer and the falling-off preventing layer is, for example, firstly an ultrafine short Aggregates of fibers (especially bundles) or their aggregates (especially aggregates containing multiple bundles in bundles) and / or mechanically divided The splittable fiber capable of generating the ultra-short fibers or the aggregate thereof (particularly, a bundle-like aggregate) is subjected to the action of a compressed gas in the same manner as described above under a condition not containing powder. After jetting into a gas from a nozzle and accumulating to form a fiber web composed of ultra-fine short fibers, utilizing the fusion property of ultra-fine short fibers, or entangled by a fluid flow such as water flow,
Alternatively, after forming a nonwoven fabric which is a fall-prevention layer by using them in combination, the powder and the ultrafine short fibers are accumulated on the nonwoven fabric by the same method as described above, and then the powder is fixed and manufactured. it can. In the case where a nonwoven fabric made of ultrafine short fibers (fall-prevention layer) is arranged on both sides of the layer to which the powder is fixed, the powder is then formed in the same manner as in the method of forming the nonwoven fabric that is the fall-prevention layer. It can be manufactured by forming a nonwoven fabric which is a fall-prevention layer on a layer to which is adhered.

Further, after forming a fiber web from the ultrafine short fibers by a usual wet method, utilizing the fusion property of the ultrafine short fibers, entanglement with a fluid flow such as a water flow, or a combination thereof. A manufactured nonwoven fabric, a nonwoven fabric obtained by a melt blow method, a nonwoven fabric prepared by forming a fiber web containing fibers that can be mechanically split by a dry method or a wet method, and then entangled by a fluid flow such as a water flow were prepared. Thereafter, the powder and the ultrafine short fibers can be accumulated on the nonwoven fabric acting as the falling-off preventing layer by the same method as described above, and then the powder can be fixed. In the case where nonwoven fabrics (fall-prevention layers) are arranged on both sides of the layer to which the powder adheres, the nonwoven fabric can be manufactured by laminating and integrating the same nonwoven fabric as the nonwoven fabric constituting the fall-off prevention layers. In addition, when the fall prevention layers are arranged on both sides of the layer to which the powder is fixed, both the fall prevention layers may have the same structure and material, or may have different structures and materials.

In forming the powder-containing fiber web by accumulating the dispersed ultrafine short fibers and the dispersed powder, the dispersed ultrafine short fibers and the dispersed powder are mixed with a reinforcing material (for example,
(A yarn, a net, a woven fabric, a knitted fabric, a fiber web, or a normal nonwoven fabric) to form a laminate. Since the strength of the powder-bonded nonwoven fabric can be improved by forming the laminate as described above, the powder-bonded nonwoven fabric of the present invention can be applied to applications requiring strength. After the powder-bonded nonwoven fabric according to the present invention is formed, the powder-bonded nonwoven fabric is integrated with a reinforcing material as described above (for example, a thread, a net, a woven fabric, a knit, a fiber web, a normal nonwoven fabric, or a film). The same effect can be obtained by forming a laminate.

Next, a manufacturing apparatus that can be used for manufacturing the powder-bonded nonwoven fabric of the present invention will be described with reference to FIG. The case where an aggregate of ultrafine short fibers having a fiber diameter of 4 μm or less and a fiber length of 3 mm or less (particularly, a bundle-like aggregate) will be described. FIG. 1 is a schematic explanatory view of one embodiment of a powder-bonded nonwoven fabric manufacturing apparatus used in the present invention.

First, a bundle of powder and ultrafine short fibers having a fiber diameter of 4 μm or less and a fiber length of 3 mm or less, together with thick fibers or their aggregates, if necessary, are mixed in a mixing device 10 such as a mixer. And then divide the bundle into smaller bundles, disperse, unravel, or mix the ultrafine fibers.

Then, the ultrafine short fibers and / or bundled ultrafine short fiber aggregates (and possibly thick fibers and / or aggregates thereof) mixed with the unraveled or powdered powder are supplied from the mixing device 10. It is supplied to the nozzle 30 via the supply pipe 11. For the transfer, an appropriate transfer gas supplied from a transfer gas supply device (not shown) provided in the mixing device 10 can be used. The compressed gas is introduced into the supply pipe 11 from the compressed gas inlet 20 before the nozzle 30. By the action of this compressed gas, the bundle of ultrafine short fiber aggregates (and possibly thick fibers and / or aggregates thereof) is
The powder is moved from the mixing device 10 to the nozzle 30 via the supply pipe 11 together with the powder, and is then squirted from the nozzle 30 into the gas 40 a in the dispersion chamber 40. This gas 40a
Due to the pressure difference between the gas inside the nozzle 30 and the gas 40a, and the turbulence formed between the jetted compressed gas and the gas 40a when the gas is jetted into the nozzle 30. Then, ultrafine short fibers 70 are generated and dispersed in the dispersion chamber 40 together with the powder 70a. Further, the ultrafine short fibers 70 and the powder 70a ejected from the nozzle 30 are made to collide with the wall 45 of the dispersion chamber 40 to promote the division and dispersion of the ultrafine short fibers 70, thereby promoting the dispersion of the powder 70a. it can. In this case, the wall 45 can function as a collision member. In addition, a collision member may be separately provided between the ejection port of the nozzle 30 and the wall portion 45. The distance between the ejection port of the nozzle 30 and the flat portion (collision portion) of the collision member is preferably 1 to 100 mm, more preferably 5 to 40 mm, and more preferably 5 to 30 m.
m, more preferably 10-30 mm, most preferably 1
0 to 20 mm.

The ultra-fine short fibers 70 and the powder 70 a dispersed in the gas 40 a in the dispersion chamber 40 descend in the dispersion chamber 40, and the support 5 made of a net provided at the bottom of the dispersion chamber 40
On the other hand, the powder-containing fiber web 80 is formed. In the manufacturing apparatus used in the present invention, as shown in FIG.
A gas suction device 6 is provided below the support 50 at the bottom of the dispersion chamber 40.
0 can be provided, and the gas suction device 60 can suck the gas 40a in the dispersion chamber 40 to promote the accumulation of the ultrafine short fibers 70 and the powder 70a. Dispersion room 4
The inside of the chamber 0 and the outside of the dispersion chamber 40 can be airtight or not airtight.

The support 50 on which the powder-containing fiber web 80 is accumulated rotates in an endless belt shape, and
The powder-containing fiber web 80 is transported in the directions 2 and 13 (the direction of arrow a in FIG. 1). Subsequently, the powder-containing fiber web 8
0 is the nozzle 3 again via the supply pipes 12 and 13.
1, 32. As in the embodiment shown in FIG. 1, not only can two nozzles be resupplied, but also one nozzle can be resupplied, or three or more nozzles can be resupplied. Alternatively, when the dispersion is sufficiently performed, the particles can be transferred to a heat-sealing apparatus 90 described later and directly sent to the bonding step.

In the supply pipes 12 and 13 as well, just before the nozzles 31 and 32, the compressed gas inlet 2
Since the compressed gas is introduced from 1 and 22, the action of the compressed gas causes the ultrafine short fibers (and possibly thick fibers) and the powder supplied from the powder-containing fiber web 80 to flow through the supply pipes 12 and 13. The nozzles 31 and 32 move to the nozzles 31 and 32, and are jetted from the nozzles 31 and 32 into the gas 41 a and 42 a in the dispersion chambers 41 and 42. At this time, similarly, the ultrafine short fibers 71 and 72 and the powders 71a and 72a are uniformly dispersed. Further, the ultra-fine short fibers 71 and 72 and the powders 71a and 72a ejected from the nozzles 31 and 32 are dispersed in the dispersion chamber 4.
Dispersion can also be facilitated by colliding with the walls 42, 47 of the first and second 42. In this case, the wall 46,
47 can act as a collision member. Also,
A collision member may be separately provided between the ejection ports of the nozzles 31 and 32 and the wall portions 46 and 47.

Gases 41a, 42a in the dispersion chambers 41, 42
Ultrafine short fibers 71, 72 and powders 71a, 7 dispersed therein
2a descends in the dispersion chambers 41 and 42, respectively, and accumulates on a support 51 made of a net provided in common at the bottom of the dispersion chambers 41 and 42. That is, the gas 4 in the dispersion chamber 41
The ultrafine short fibers 71 and the powder 71a dispersed in 1a are lowered in the dispersion chamber 41 and accumulated on the support 51 to form the single-layer powder-containing fiber web 81, and then the endless belt-like support is formed. 51 together with the direction of the dispersion chamber 42 (arrow b in FIG. 1).
Direction). The gas 42 in the dispersion chamber 42
The ultra-fine short fibers 72 and the powder 72a dispersed in the fiber web a descend in the dispersion chamber 42 and further accumulate on the single-layer powder-containing fiber web 81 on the support body 51 to form a laminated powder-containing fiber web. 82 is formed. However, the laminated powder-containing fiber web 82 thus formed is a single-layer powder-containing fiber web 8.
Since the ultrafine short fibers constituting 0 are dispersed again, a clear two-layer structure does not exist.

In the manufacturing apparatus used in the present invention, FIG.
As shown in the figure, a gas suction device 61 can be provided below the support body 51 at the bottom of the dispersion chambers 41 and 42.
a, 42a are sucked, and ultrafine short fibers 71, 72 and powder 7
Accumulation of 1a and 72a can be promoted. Further, as shown in FIG. 1, the support 51 and the gas suction device 61
It may be provided in common for a plurality of dispersion chambers, or may be provided separately and independently for each of the plurality of dispersion chambers.

Next, an endless belt-like support 51
Transports the laminated powder-containing fiber web 82 to the heat fusion device 90, and the ultrafine short fibers and / or powder, and in some cases, the thick fiber are fused by the action of heat in the heat fusion device 90. Thus, the powder fixed nonwoven fabric 83 can be formed.
Then, the non-woven fabric 83 is fixed to the winding device 100.
Is wound up.

The sheet material according to the present invention contains at least one layer of the above-mentioned powder-fixed nonwoven fabric layer. That is, the sheet material according to the present invention comprises a single layer of the above-mentioned powder-fixed nonwoven fabric layer, or one or more of the above-mentioned powder-fixed nonwoven fabric layers and one or more powder fall-off prevention layers ( (Preferably one or two layers), or one or more reinforcing layers. As a reinforcing layer, a normal yarn layer, a net layer,
Examples thereof include a woven layer, a knitted layer, a fiber web layer, and an ordinary nonwoven layer. The sheet material including the powder-fixed nonwoven fabric layer and the reinforcing layer is, for example, a powder-fixed nonwoven fabric layer obtained by accumulating a powder-containing fiber web on the reinforcement layer and bonding the powder-containing fiber web and the reinforcing layer. Can be produced at the same time as the formation, or can be produced by bonding the reinforcing layer and the powder-fixed nonwoven fabric layer by a suitable bonding means. Since the sheet material according to the present invention contains the above-mentioned powder-bonded nonwoven fabric layer, it can be advantageously used in the field utilizing various characteristics of powder. For example, an ozone decomposing sheet for an electrophotographic apparatus, a toilet deodorizing apparatus, or an ozone generator; an ion exchange sheet for an ion exchange water purifier;
Sheets for catalysts for automobiles or chemical reaction equipment; deodorizing or deodorizing sheets for household goods, sanitary goods, filters, shoes, etc .; fiber reinforced plastics (FRP) and sheet prepregs (SMC); Alternatively, it can be used for various uses such as a fireproof board.

[0072]

EXAMPLES The present invention will be described below in more detail with reference to examples, but these examples do not limit the scope of the present invention.

Example 1 A sea-island-type fiber obtained by a composite spinning method (fineness = 1.7 dtex; fiber length 1 mm
Cut into pieces). This sea-island type fiber is
After being immersed in a mass% aqueous sodium hydroxide solution to extract and remove the polylactic acid as a sea component by hydrolysis, it is air-dried to obtain polypropylene ultra-short fibers (fiber diameter = 2 μm;
Fiber length = 1 mm; not fibrillated; stretched; has substantially the same diameter in the fiber axis direction;
An aggregate of the ultrafine short fibers A in which the adhesion rate of the attached matter is less than 0.02 mass%) was obtained.

In the sea component composed of polylactic acid, two island components composed of high-density polyethylene and polypropylene were included.
There are 5 sea-island fibers obtained by the composite spinning method (fineness =
1.7 dtex; one cut to a fiber length of 1 mm). This sea-island type fiber is immersed in a 10 mass% sodium hydroxide aqueous solution to extract and remove the polylactic acid as a sea component by hydrolysis, and then air-dried, and then the sea-island type ultra-small short polypropylene in which polypropylene is scattered in high-density polyethylene. Fiber (fiber diameter = 2 µm; fiber length = 1 mm; not fibrillated; stretched; has substantially the same diameter in the fiber axis direction; adhesion rate of attached matter = 0.02 mass
%) Was obtained as an aggregate of sea-island type ultrafine short fibers B in a bundle.

Further, activated carbon having an average particle size of 6 μm was prepared as a powder.

Next, a powder-bonded nonwoven fabric according to the present invention was prepared using an apparatus similar to the manufacturing apparatus shown in FIG. That is, a bundle of bundles of ultrafine short fibers A, a bundle of bundles of sea-island type ultrafine short fibers B, and activated carbon are supplied to a mixer at a mass ratio of 10: 5: 85, and these are melted and mixed. , The cross-sectional shape at the jet port is circular (diameter = 8.5)
mm) (a cross section at the supply side of the Venturi tube = circular (cone = 3 mm) truncated cone) at the supply side of the Venturi tube and laminar compressed air from the compressed gas inlet provided before the Venturi tube. (Pressure = 6 kg / c
m ² ), the mixture is ejected from the venturi tube into the air (gas passing speed at the vent hole of the venturi tube = 118 m / s), and collides with a baffle plate provided in front of the venturi tube outlet. Activated carbon and polypropylene ultra-short fibers A and sea-island ultra-short fibers B were dispersed therein. The distance between the vent of the Venturi tube and the baffle plate was 15 mm.

Next, the dispersed activated carbon, polypropylene ultrafine short fibers and sea-island type ultrafine short fibers were placed on a non-woven fabric substrate (having a basis weight of 30
g / m ² of polyester fiber spunbonded nonwoven fabric). At the time of accumulation, air was sucked (2 m) by a suction box installed under the support.
³ / min).

Next, the spunbonded nonwoven fabric substrate supporting the powder-containing fiber web is supplied to an oven set at a temperature of 130 ° C., and is subjected to a heat treatment for 3 minutes.
A nonwoven fabric-based laminated powder-bonded nonwoven fabric having a thickness of 0 g / m ² and a thickness of 1.2 mm was produced. The powder-bonded non-woven fabric layer of the non-woven fabric substrate-laminated powder-bonded non-woven fabric has a polypropylene ultra-fine short fiber A and a sea-island ultra-fine short fiber B entangled so as to surround the activated carbon powder, and a sea-island ultra-fine short fiber. Due to the high-density polyethylene component constituting B, polypropylene ultra-short fibers A and sea-island ultra-short fibers B, and sea-island ultra-short fibers B and activated carbon powder were in a fused state.

The thus obtained nonwoven fabric substrate laminated powder
The non-woven fabric substrate is peeled from the body-bonded non-woven fabric,
When only various physical properties were measured, only the basis weight was 40 g.
/ M ^Two, The thickness is 1.1 mm and the apparent density is 0.036 g /
cm^ThreeThe mass ratio of the ultrafine fibers A and B is 15 mass
%Met. The powder-bonded non-woven fabric was placed in hot water for 15 minutes.
For 15 minutes in hot methanol.
Powder of total adhering substances with adhering substances extracted by immersion for 5 minutes
Percentage to the mass of the fixed nonwoven fabric
It was less than 0.02 mass%.

A filter unit (peak height = 20 mm,
(Pitch = 2 mm) and air containing toluene at a concentration of 25 ppm was applied at a surface wind speed of 14 cm / sec. , The toluene removal rate at the filter unit outlet showed a high deodorizing performance of 99% or more. In addition, even when vibration was applied, no falling off of the activated carbon from the nonwoven fabric substrate laminated powder-fixed nonwoven fabric was observed.

[0080]

Example 2 A bundle of bundles of ultrafine short fibers A and a bundle of bundles of sea-island type ultrafine short fibers B produced in the same manner as in Example 1 were prepared. In addition, an electrolyte manganese dioxide powder (average particle size = 3 μm) was prepared as a powder.

Next, a powder-bonded nonwoven fabric according to the present invention was prepared in the same manner as in Example 1 using the same apparatus as the manufacturing apparatus shown in FIG. That is, the bundle of bundled ultrafine short fibers A, the bundle of sea-island type ultrafine short fibers B, and the electrolyte manganese dioxide powder are supplied to a mixer at a mass ratio of 6: 9: 85, and these are unraveled. After mixing, the mixture was made to have a circular cross section at the jet port (diameter = 3.
2 mm) continuously, and at the same time, a laminar compressed air (pressure = 6 kg / cm ² ) is introduced from a compressed gas inlet provided before the tapered nozzle.
The mixture is ejected from the tapered nozzle into the air in the dispersion chamber (gas passing speed at the outlet of the tapered nozzle = 1600)
m / s), and the polypropylene ultra-short fibers A, the sea-island ultra-short fibers B, and the electrolytic manganese dioxide powder were dispersed in a dispersion chamber.

Next, the dispersed electrolyte manganese dioxide powder, polypropylene ultrafine short fiber A and sea-island type ultrafine short fiber B were placed on a non-woven fabric base material (having a basis weight of 30 g / m 2). ⁽² ) polyester fiber spunbonded nonwoven fabric) to form a powder-containing fiber web-nonwoven fabric substrate composite. At the time of accumulation, air was sucked (2 m ³ / min) by a suction box provided below the support.

Next, this powder-containing fibrous web-nonwoven fabric base composite material was supplied to an oven set at a temperature of 130 ° C., and heat-treated for 3 minutes to give a basis weight of 90 g / m ² and a thickness of 1.0 mm. A non-woven fabric substrate laminated powder-bonded non-woven fabric was manufactured. The powder-bonded non-woven fabric layer of the non-woven fabric substrate laminated powder-bonded non-woven fabric has a polypropylene ultra-fine short fiber A and a sea-island ultra-fine short fiber B entangled so as to surround the electrolyte manganese dioxide powder, and a sea-island ultra-fine fiber. Due to the high-density polyethylene component constituting the short fibers B, the ultrafine short fibers of polypropylene A and the ultrafine short islands-in-sea fibers B, and the short fibers of islands-in-sea type B and the electrolytic manganese dioxide powder were in a fused state.

The nonwoven fabric substrate was peeled off from the nonwoven fabric laminated powder-fixed nonwoven fabric, and various physical properties were measured only for the powder-fixed nonwoven fabric. The basis weight was 60 g / m ² , the thickness was 0.9 mm, and the apparent value was 0.9 mm. The density was 0.067 g / cm ³ , and the mass ratio of the ultrafine short fibers A and B was 15 mass%. In addition, the mass of the powder-fixed nonwoven fabric of the total amount of adhered substances of the deposits extracted by immersing the powder-fixed nonwoven fabric in hot water for 15 minutes and the deposits extracted by immersion in hot methanol for 15 minutes Percentage (adhesion rate of deposits) to 0.02mas
s%.

This non-woven fabric substrate laminated powder-bonded non-woven fabric is pressed by an area calender (temperature = 130 ° C.) to a thickness of 0.3 mm, and then corrugated (height = 2).
mm, pitch = 1.5 mm), and 10 ppm ozone gas was passed through.
ppm or less, showing excellent ozonolysis performance. Also, even when vibration was applied, no dropout of the electrolyte manganese dioxide powder from the nonwoven fabric-laminated-powder-fixed nonwoven fabric was observed.

[0086]

Example 3 In a sea component comprising a copolymerized polyester,
There are 61 island components composed of crystalline polystyrene, and sea-island type fibers (fineness = 2.3 dte) obtained by the composite spinning method.
x; cut to a fiber length of 0.5 mm).
This sea-island type fiber is immersed in a 10 mass% aqueous sodium hydroxide solution to extract and remove the copolyester as a sea component by hydrolysis, and then air-dried to obtain a crystalline polystyrene ultrafine short fiber (fiber diameter = 1.1 μm). Fiber length = 0.
5 mm; not fibrillated; stretched; have substantially the same diameter in the fiber axis direction; adhesion rate of attached matter = less than 0.02 mass%). Obtained.

An aggregate of bundled ultrafine short fibers B produced in the same manner as in Example 1 and spherical alumina powder (average particle size = 25 μm) were prepared as powder.

Next, a powder-bonded nonwoven fabric according to the present invention was prepared using an apparatus similar to the manufacturing apparatus shown in FIG. That is, bundled ultrafine short fiber C aggregate, bundled ultrafine short fiber B aggregate, and spherical alumina powder,
After being supplied to a mixer at a mass ratio of 1: 1: 98 to dissolve and mix the mixture, the mixture is continuously tapered with a circular cross-sectional shape (diameter = 3.2 mm) at an ejection port. And laminar compressed air (pressure = 6 kg / cm ² ) is introduced from a compressed gas inlet provided in front of the convergent nozzle, and the mixture is ejected from the convergent nozzle into the air in the dispersion chamber ( Tapered nozzle 30
At 1600 m / s) to disperse crystalline polystyrene ultrafine short fiber C, sea-island type ultrafine short fiber B, and spherical alumina in a dispersion chamber.

Next, the dispersed crystalline polystyrene ultra-short fibers C, sea-island type ultra-short fibers B and spherical alumina were placed on a non-woven fabric base material (having a basis weight of 30 g / m 2) placed on a support made of a net. ⁽² ) polyester fiber spunbonded nonwoven fabric) to form a powder-containing fiber web-nonwoven fabric substrate composite. At the time of accumulation, air was sucked (2 m ³ / min) by a suction box provided below the support.

Next, this powder-containing fiber web-nonwoven fabric substrate composite was supplied to an oven set at a temperature of 130 ° C., and heat-treated for 3 minutes to give a basis weight of 410 g / m ² .
A 0.55 mm thick nonwoven fabric substrate laminated powder-bonded nonwoven fabric was produced. The powder-bonded non-woven fabric layer of the non-woven fabric substrate laminated powder-bonded non-woven fabric is such that the crystalline polystyrene ultra-fine short fibers C and the sea-island ultra-fine short fibers B are entangled so as to surround the spherical alumina, and the sea-island ultra-fine fibers. Due to the high-density polyethylene component constituting the short fiber B, the crystalline polystyrene ultrafine short fiber C and the sea-island ultrafine short fiber B, and the sea-island ultrafine short fiber B and spherical alumina were in a fused state.

The nonwoven fabric substrate was peeled from the nonwoven fabric laminated powder-fixed nonwoven fabric, and various physical properties were measured for only the powder-fixed nonwoven fabric. The basis weight was 380 g / m ² , the thickness was 0.45 mm, and the apparent The density was 0.844 g / cm ³ , and the mass ratio of the ultrafine short fibers was 2 mass%. In addition, the mass of the powder-fixed nonwoven fabric of the total amount of adhered substances of the deposits extracted by immersing the powder-fixed nonwoven fabric in hot water for 15 minutes and the deposits extracted by immersion in hot methanol for 15 minutes Was less than 0.02 mass%.

[0092] Four powder-fixed non-woven fabric layers are superimposed,
Pressing with a hot press at a temperature of 130 ° C. (pressure = 50
kg / cm ² ), a flexible sheet with a high alumina filling rate and high thermal conductivity (basis weight = 1520 g /
m ² ; thickness = 0.75 mm; apparent density = 2.03 g / c
m ³ ) was obtained. This sheet does not lose alumina,
It was excellent in handleability and strength.

[0093]

Example 4 A commercially available polyester ultrafine short fiber (fiber diameter =
3.2 μm; fiber length = 3.0 mm; Teijin)
The fiber oil adhering to the fiber surface was extracted and removed in acetone.

A bundle of ultrafine short fibers A and a bundle of ultrafine short fibers B produced in the same manner as in Example 1 were prepared. Further, spherical alumina powder (average particle size = 25 μm) was prepared as a powder.

Next, using the same apparatus as the production apparatus shown in FIG. 1, the polyester ultra-short fibers, the bundle of bundles of ultra-short fibers A, the bundle of sea-island ultra-fine fibers B, and the spherical alumina powder Was supplied to the mixer at a mass ratio of 2: 2: 4: 92 to dissolve and mix the mixture.
3.2 mm) and continuously feeds it to a tapered nozzle which tapers, and introduces laminar compressed air (pressure = 6 kg / cm ² ) from a compressed gas inlet provided before the nozzle. Jets the mixture into the air in the dispersing chamber (gas passing speed at the outlet of the convergent nozzle = 16)
00 m / s) to disperse the polyester ultrafine short fibers, ultrafine short fibers A, sea-island type ultrafine short fibers B, and spherical alumina powder.

Then, the dispersed polyester ultra-short fibers, polypropylene ultra-short fibers A, sea-island ultra-short fibers B, and spherical alumina powder were placed on a non-woven fabric substrate which was placed on a support made of a net. ^On a polyester fiber spunbonded nonwoven fabric having a basis weight of 30 g / m2) to form a powder-containing fiber web-nonwoven fabric substrate composite. At the time of accumulation, air was sucked by a suction box installed under the support (2 m ³ / mi).
n).

Next, the powder-containing fibrous web-nonwoven fabric substrate composite was supplied to an oven set at a temperature of 130 ° C., and heat-treated for 3 minutes to give a basis weight of 450 g / m ² .
A 0.65 mm thick nonwoven fabric substrate laminated powder-bonded nonwoven fabric was produced. The powder-bonded non-woven fabric layer of this non-woven fabric substrate laminated powder-bonded non-woven fabric has polyester ultra-fine short fibers, polypropylene ultra-fine short fibers A and sea-island type ultra-fine short fibers B entangled so as to surround the spherical alumina powder. Due to the high-density polyethylene component constituting the sea-island type ultra-fine short fibers B, the ultra-fine short fibers were fused to each other and the sea-island-type ultra-fine short fibers B were fused to spherical alumina.

The nonwoven fabric substrate was peeled from the nonwoven fabric laminated powder-fixed nonwoven fabric, and various physical properties were measured for only the powder-fixed nonwoven fabric. The basis weight was 420 g / m ² , the thickness was 0.55 mm, and the apparent The density was 0.764 g / cm ³ , and the mass ratio of the ultrafine fibers was 8 mass%. In addition, the mass of the powder-fixed nonwoven fabric of the total amount of adhered substances of the deposits extracted by immersing the powder-fixed nonwoven fabric in hot water for 15 minutes and the deposits extracted by immersion in hot methanol for 15 minutes Was less than 0.02 mass%.

[0099] Two powder-bonded non-woven fabrics are superposed and pressed by a hot press at a temperature of 130 ° C (pressure = 50 kg).
/ Cm ² ), a flexible sheet with high alumina filling rate and high thermal conductivity (basis weight = 840 g / m ² ; thickness = 0.43 mm; apparent density = 1.95 g / cm ³ ) was obtained. Obtained. This sheet was excellent in handleability and strength without removing alumina.

[0100]

Example 5 In a sea component composed of a copolymerized polyester,
About 3900 island components consisting of poly-4-methylpentene
Sea-island type fiber (fineness =
8.8 dtex; cut to a fiber length of 0.5 mm)
Was prepared. This sea-island type fiber is immersed in a 10 mass% sodium hydroxide aqueous solution to extract and remove the copolyester as a sea component by hydrolysis, and then air-dried.
Poly-4-methylpentene ultra-fine short fiber (fiber diameter = 0.4
μm; fiber length = 0.5 mm; not fibrillated;
An aggregate of poly-4-methylpentene ultra-fine short fibers D in a bundle form, which has been drawn; the diameter has changed in the fiber axis direction; .

The aggregate of the crystalline polystyrene ultrafine short fibers C produced in the same manner as in Example 3 and the aggregate of the bundled sea-island type ultrafine short fibers B produced in the same manner as in Example 1 were used. Prepared.

Next, using an apparatus similar to the manufacturing apparatus shown in FIG. 1, an aggregate of bundled poly-4-methylpentene ultrafine short fibers D, an aggregate of crystalline polystyrene ultrafine short fibers C, and Aggregate of sea-island type ultrafine short fiber B is 40: 2
The mixture was fed to a mixer at a mass ratio of 0:40 to dissolve and mix these fibers. Then, the mixture was continuously formed into a tapered nozzle having a circular cross-sectional shape (diameter = 3.2 mm) at an ejection port and having a tapered shape. At the same time, laminar compressed air (pressure = 6 kg / cm ² ) is introduced from a compressed gas inlet provided before the tapered nozzle, and the mixture is ejected from the tapered nozzle into the air in the dispersion chamber (tapered). The gas passing speed at the nozzle of the nozzle = 1600 m / s) to disperse the poly-4-methylpentene ultrafine short fiber D, the crystalline polystyrene ultrafine short fiber C, and the sea-island type ultrafine short fiber B.

Then, the dispersed poly-4-methylpentene ultrafine short fiber D, crystalline polystyrene ultrafine short fiber C, and sea-island type ultrafine short fiber B were placed on a support made of a net. It is accumulated on a nonwoven fabric substrate (a spunbonded nonwoven fabric made of polyester fiber having a basis weight of 30 g / m ² ), and an ultrafine short fiber web (a fall-prevention layer; basis weight = 5 g /
m ² ) —formed a nonwoven substrate composite. At the time of accumulation, air was sucked (2 m ³ / min) by a suction box provided below the support.

Next, the same poly-bundle as described above was used.
Aggregates of 4-methylpentene ultrafine fibers D, aggregates of crystalline polystyrene ultrafine fibers C produced in the same manner as in Example 3, aggregates of sea-island ultrafine fibers B produced in the same manner as in Example 1. And an anatase type titanium dioxide powder (average particle size = 0.2 μm) as a powder.

Then, poly-4-methylpentene ultra-thin
A collection of fibers D, a collection of crystalline polystyrene ultrafine short fibers C
Coalescence, aggregate of sea-island type ultrafine short fiber B, and anatase type
Mix titanium dioxide powder at a mass ratio of 3: 6: 6: 85.
After mixing and mixing these
These mixtures were prepared using a circular cross section at the spout (diameter
= 3.2 mm) and continuously feed to a tapered nozzle
And a compressed gas guide provided in front of the convergent nozzle.
Laminar compressed air from the inlet (pressure = 6 kg / cm ^TwoLed)
And the mixture is introduced into the air in the dispersion chamber through the tapered nozzle.
(Gas passing speed at the outlet of the convergent nozzle = 1)
600 m / s) to obtain titanium dioxide powder, poly-4-me
Chilpentene ultrafine fiber, crystalline polystyrene ultrafine fiber
The fibers and sea-island type ultrafine short fibers were dispersed.

Then, the dispersed poly-4-methylpentene ultrafine short fiber D, crystalline polystyrene ultrafine short fiber C, sea-island type ultrafine short fiber B, and titanium dioxide powder were mixed with the above ultrafine short fiber web (prevention of falling off). Layer; basis weight = 5 g /
m ² )-collected on the ultrafine short fiber web of the nonwoven fabric substrate composite material to form a powder-containing fiber web-ultrafine short fiber web-nonwoven fabric substrate composite material. At the time of accumulation, air was sucked (2 m ³ / min) by a suction box provided below the support.

Next, an aggregate of poly-4-methylpentene ultrafine short fibers D, an aggregate of crystalline polystyrene ultrafine short fibers C, and an aggregate of sea-island type ultrafine short fibers B were produced in exactly the same manner as described above. Dispersed and dispersed, and collected on the powder-containing fiber web of the powder-containing fiber web-ultrafine short fiber web-nonwoven fabric substrate composite material; A nonwoven substrate composite was formed.

Next, this ultrafine short fiber web-powder-containing fiber web-ultrafine short fiber web-nonwoven fabric base material composite was
It is supplied to an oven set to a temperature of 130 ° C., and heat-treated for 3 minutes to obtain a basis weight of 270 g / m ² and a thickness of 0.42 m.
m was prepared. The powder-bonded non-woven fabric layer of the non-woven fabric substrate-laminated powder-fixed non-woven fabric has a poly-4-methylpentene ultrafine short fiber D, a crystalline polystyrene ultrafine short fiber C, and a sea-island type ultrafine short fiber B around the titanium dioxide powder. The ultra-short fibers and the sea-island ultra-short fibers B and titanium dioxide were fused together by the high-density polyethylene component constituting the sea-island ultra-short fibers B while being entangled so as to surround them. In addition, the titanium dioxide powder was in a state where it could be prevented from falling off by a fiber layer (fall-out preventing layer) derived from the ultra-fine short fiber web composed of only ultra-fine short fibers.

The nonwoven fabric substrate was peeled off from the nonwoven fabric-laminated powder-bonded nonwoven fabric, and various physical properties of only the three-layer structure powder-fixed nonwoven fabric were measured.
m ² , thickness 0.32 mm, apparent density 0.750 g /
cm ³ , the mass ratio of the ultrafine short fibers in the powder-fixed nonwoven fabric layer was 15 mass%. In addition, the three-layer structure powder-bonded nonwoven fabric was immersed in hot water for 15 minutes and extracted, and the total amount of adhering substances of the extraneous matter extracted by immersion in hot methanol for 15 minutes was determined by the three-layer structure. The percentage of the mass of the powder-bonded nonwoven fabric (the rate of adhesion of the deposit) is 0.02 mass.
%.

A filter unit (crest height = 20 mm; pitch = 2 mm) was prepared by pleating this nonwoven fabric-laminated powder-fixed nonwoven fabric. Toluene was irradiated at a concentration of 100 ppb while irradiating the filter unit with ultraviolet rays. When the containing air was passed at a speed of 20 cm / s,
The removal rate of toluene at the filter unit outlet is 8
Reached 0%. Further, even when vibration was applied to the nonwoven fabric-fixed nonwoven fabric with the laminated nonwoven fabric substrate, the titanium dioxide powder did not fall off.

[0111]

Example 6 An aggregate of bundled sea-island type ultrafine short fibers B produced in the same manner as in Example 1 was prepared.

Next, the aggregate of sea-island type ultra-fine short fibers B is supplied to a mixer and unraveled.
The cross section of the aggregate at the jet port is circular (diameter =
3.2 mm) and continuously feeds it to a tapered nozzle which tapers, and introduces laminar compressed air (pressure = 6 kg / cm ² ) from a compressed gas inlet provided before the nozzle. Jets the mixture into the air in the dispersing chamber (gas passing speed at the outlet of the convergent nozzle = 16)
00 m / s) to disperse the sea-island type ultrafine short fibers B.

Next, this dispersed sea-island type ultrafine short fiber B was placed on a nonwoven fabric substrate (a spunbonded nonwoven fabric made of polyester fiber having a basis weight of 30 g / m ² ) placed on a support made of a net. The web was accumulated to form an ultrafine short fiber web (basis weight = 5 g / m ² ) -nonwoven fabric substrate composite. In addition,
At the time of accumulation, air was sucked (2 m ³ / min) by a suction box installed below the support.

Next, a bundle of sea-island type ultrafine short fibers B produced in the same manner as in Example 1 and low-density polyethylene powder (average particle size = 12 μm; Sumitomo Seika )) Was prepared.

Next, the sea-island type ultrafine short fiber B aggregate and the low-density polyethylene powder were supplied to a mixer at a mass ratio of 5:95 to be melted and mixed. Is circular (diameter = 3.2m
m), the laminar flow compressed air (pressure = 6 kg / cm ² ) is introduced from the compressed gas inlet provided before the tapered nozzle while continuously supplying the tapered nozzle to the tapered nozzle. The mixture is jetted into the air of the dispersion chamber (gas passing speed at the jet port of the convergent nozzle = 1600)
m / s) to disperse the low-density polyethylene powder and the sea-island type ultrafine short fibers B.

Next, the dispersed low-density polyethylene powder and sea-island type ultrafine short fibers B are integrated on the ultrafine short fiber web of the aforementioned ultrafine short fiber web (basis weight = 5 g / m ² ) -nonwoven fabric composite material. Thus, a powder-containing fiber web-ultrafine short fiber web-nonwoven fabric substrate composite was formed. At the time of accumulation, air was sucked (2 m ³ / min) by a suction box provided below the support.

Next, this powder-containing fiber web-ultrafine short fiber web-nonwoven fabric substrate composite was supplied to an oven set at a temperature of 107 ° C., and heat-treated for 5 minutes to give a basis weight of 118 g / m ² and a A 0.55 mm thick nonwoven fabric substrate laminated powder-bonded nonwoven fabric was produced. This non-woven fabric substrate laminated powder-bonded non-woven fabric has sea-island type ultrafine short fibers B entangled so as to surround the low-density polyethylene powder, and the high-density polyethylene component constituting the sea-island type ultra-fine short fibers B Part of polyethylene powder is melted, sea-island type ultrafine short fiber B
Each other and the sea-island type ultrafine short fiber B and the low-density polyethylene powder were in a fused state. In addition, sea-island type ultrafine short fiber B
The fiber layer (fall-prevention layer) derived from the ultra-fine short fiber web made of only the low-density polyethylene resin powder was in a state where it could be prevented from falling off.

The two-layer structure powder-bonded non-woven fabric was peeled off from the non-woven fabric substrate laminated powder-bonded non-woven fabric, and various physical properties of only the two-layer structure powder-bonded non-woven fabric were measured.
8 g / m ² , thickness 0.45 mm, apparent density 0.19
At 6 g / cm ³ , the mass ratio of the ultrafine short fibers in the powder-bonded nonwoven fabric layer was 5 mass%. In addition, the low-density polyethylene powder did not fall off in the two-layer structure powder-fixed nonwoven fabric. Further, the two-layer structure of the total amount of adhering substances of the adhered substance extracted by immersing the two-layer structure powder-bonded nonwoven fabric in hot water for 15 minutes and the extraneous substance extracted by immersing in hot methanol for 15 minutes is shown. The percentage based on the mass of the powder-fixed nonwoven fabric (the attachment ratio of attached matter) was less than 0.02 mass%.

When this two-layer structure powder-bonded nonwoven fabric was heat-treated in an oven set at 125 ° C. for 5 minutes, the low-density polyethylene powder melted to form a film, and the sea-island type ultrafine short fiber B was contained in the low-density polyethylene. Is a fiber-reinforced plastic (FRP) sheet excellent in flexibility and strength (basis weight = 88 g / m ² ; thickness = 0.14 mm; apparent density = 0.629 g / cm ³ ). Fiber B was found to serve as an aggregate in the FRP.

[0120]

The powder-bonded nonwoven fabric of the present invention is hard to fall off even if the powder has a small particle size, and can exhibit the original function of the powder. The average particle size of the powder is 50μ
m or less, the function of the powder can be maximized. When the mass ratio of the layer of the ultrafine short fibers to which the powder is fixed is 1 to 40 mass%, the amount of the powder is large, so that the function of the powder can be maximized.

When the adhesion rate of the deposits adhering to the layer to which the powder is adhered is 0.5 mass% or less, the function of the powder is not impaired by the deposits. If at least one surface of the layer to which the powder is fixed is further provided with a fall-off prevention layer capable of preventing the powder from falling off, the powder can be more reliably prevented from falling off. According to the method for producing a powder-bonded nonwoven fabric of the present invention, powder is fixed to a fiber web formed by a method other than a wet method in which ultrafine short fibers having a fiber diameter of 4 μm or less and a fiber length of 3 mm or less are dispersed. The manufactured nonwoven fabric can be easily manufactured.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a manufacturing apparatus capable of manufacturing a powder-bonded nonwoven fabric of the present invention.

[Explanation of symbols]

10 mixing apparatus; 11, 12, 13 supply pipe;
20, 21, 22, ... compressed gas inlet; 30, 31,
32 ... nozzle; 40, 41, 42 ... dispersion chamber; 4
0a, 41a, 42a ... gas; 45, 46, 47
..Walls of dispersion chambers; 50, 51.
DESCRIPTION OF SYMBOLS 1 ... Gas suction device; 70, 71, 72 ... Ultra-fine short fiber; 70a, 71a, 72a ... Powder;
Fiber web; 81: single-layer fiber web; 82: laminated fiber web; 83: heat-sealed nonwoven fabric; 90: heat-sealing device;

Claims (14)

[Claims] 1. A powder formed from a powder-containing fiber web formed by a method other than a wet method, comprising a dispersed state of a powder and ultrafine short fibers having a fiber diameter of 4 μm or less and a fiber length of 3 mm or less. Fixed non-woven fabric. 2. The powder-fixed nonwoven fabric according to claim 1, wherein the average particle size of the powder is 50 μm or less. 3. The powder fixed nonwoven fabric according to claim 1, wherein the mass ratio of the ultrafine short fibers to the total mass of the powder fixed nonwoven fabric is 1 to 40 mass%. 4. The powder-bonded nonwoven fabric according to claim 1, wherein the adhesion rate of the deposit is 0.5 mass% or less. 5. The powder-fixed nonwoven fabric according to claim 1, wherein the ultrafine short fibers comprise island components obtained by removing sea components of sea-island fibers. 6. The powder-fixed nonwoven fabric according to claim 1, wherein the ultrafine short fibers are made of an organic component. 7. An aggregate of ultra-fine short fibers having a fiber diameter of 4 μm or less and a fiber length of 3 mm or less, or a group thereof, and / or mechanically divided to have a fiber diameter of 4 μm or less and a fiber length of 3 mm. Dividable fibers that can generate the following ultra-short fibers,
Alternatively, the aggregate thereof, together with the powder, is ejected from a nozzle into a gas by the action of a compressed gas to divide the ultrafine short fiber aggregate or an aggregate group thereof into ultrafine short fibers, and / or Dividing the conductive fibers or the aggregate thereof into ultrafine short fibers and dispersing the powder, accumulating the dispersed ultrafine short fibers and the powder to form a powder-containing fiber web, and the obtained powder. A step of fixing powder contained in the powder-containing fiber web when forming the nonwoven fabric from the fiber-containing web. 8. The method according to claim 7, wherein the aggregate of the ultrafine short fibers is a bundle. 9. An aggregate of ultra-short fibers or a group thereof, and / or an extra-fine fiber-generating splittable fiber or an aggregate thereof are supplied to the nozzle before removing attached matter thereof. The method according to claim 7, wherein the step is performed. 10. The production method according to claim 7, wherein a flow of the gas supplied to the nozzle is substantially a laminar flow. 11. The method according to claim 11, wherein the aggregate of ultra-fine short fibers or an aggregate thereof, and / or the splittable fibers capable of generating ultra-fine short fibers or an aggregate thereof are ejected from a nozzle together with powder, and then the nozzle The manufacturing method according to any one of claims 7 to 10, wherein the collision is performed with a collision member provided in front of the injection port. 12. A powder formed from a powder-containing fiber web formed by a method other than a wet method, comprising a dispersed state of a powder and ultrafine short fibers having a fiber diameter of 4 μm or less and a fiber length of 3 mm or less. A sheet material comprising at least one layer of a fixed nonwoven fabric. 13. The sheet material according to claim 12, further comprising a powder-free layer on at least one surface of the powder-fixed nonwoven fabric layer. 14. A fiber having a fiber diameter of 4 μm or less and a fiber length of 3 mm
Aggregates of the following ultra-short fibers or aggregates thereof,
And / or mechanically splitting a splittable fiber capable of generating ultrafine short fibers having a fiber diameter of 4 μm or less and a fiber length of 3 mm or less, or an aggregate thereof, together with powder, by the action of compressed gas. And squirting it into a gas to divide the ultrafine short fiber aggregate or the aggregate thereof into ultrafine short fibers, and / or split the splittable fiber or the aggregate thereof into ultrafine short fibers and powder Dispersing, dispersing the ultrafine short fibers and powder to form a powder-containing fiber web, and forming a nonwoven fabric from the obtained powder-containing fiber web, Fixing the powder contained therein, and further bonding the powder-free layer simultaneously with the powder contained therein.