JP3188796B2 - Method for manufacturing container-shaped multilayer filter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a container-shaped multilayer filter .
Regarding the manufacturing method , more specifically, it is integrally molded into a container shape,
The present invention relates to a method for producing a container-shaped multilayer filter having excellent air purification and component extraction performance.

[0002]

2. Description of the Related Art Conventionally, as general-purpose materials for filters,
Mainly paper, woven fabric, non-woven fabric, etc. are used.
From the viewpoints of downsizing, disposable, and simplicity of a filter unit, a method of three-dimensionally forming and using a filter material has attracted attention. Particularly, ultrafine fiber nonwoven fabrics are often used in the field of filters for the purpose of purifying air or improving component extraction performance.However, when forming the ultrafine fiber nonwoven fabric into a three-dimensional filter, the ultrafine fiber nonwoven fabric is melted in a mold. There are problems such as easy attachment and heat shrinkage of the ultrafine fiber nonwoven fabric, and the molded filter is easily deformed.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art, and to provide excellent workability by hot press molding at the time of manufacturing, and appropriate mold retention. Manufacturing method of container-shaped multilayer filter with filter performance
Is to provide a law .

[0004]

The invention claimed in the present application is as follows. (1) Ultrafine fiber non-woven fabric having an average fiber diameter of 0.5 to 6.0 μm
A thermoplastic synthetic fiber nonwoven fabric having an average fiber diameter of 10 to 100 μm is laminated on at least one side of
And manufacturing the container-shaped multilayer filter , wherein at least a part of the laminate is joined and integrally formed into a container having a flange portion and a molded portion extended from the flange portion. Method. (2) apparent density 0.05 of the microfibrous non-woven fabric
0.5 g / c m ^3, and the container-like method for manufacturing a multilayer filter which (1) wherein, characterized in that the elongation at break under the molding temperature of the thermoplastic synthetic fiber nonwoven fabric is 50% or more.

The ultra-fine fiber nonwoven fabric used in the present invention is, for example, a melt-blowing method in which a molten polymer such as polypropylene or polyester is jetted from a spinning nozzle together with a high-pressure gas flow, or a polymer such as polyethylene or polypropylene is dissolved in an organic solvent to obtain a high-temperature high-pressure. Make a solution of
This can be obtained by a method such as a flash spinning method in which the pressure is reduced by a spinning nozzle and the organic solvent is explosively vaporized.

In the present invention, the average fiber diameter of the ultrafine fiber nonwoven fabric is 0.5 to 6.0 μm, preferably 1.0 to 4.0.
It is in the range of μm. The average fiber diameter of the microfiber nonwoven fabric is 0.
If it is less than 5 μm, the fiber strength and air permeability / liquid permeability are inferior. On the other hand, if it exceeds 6.0 μm, the fiber strength is improved, but the air permeability / liquid permeability is too good and the filter performance becomes insufficient. The apparent density of the ultrafine nonwoven fabric is 0.05 to 0.5 g / cm.
The range of ³ is preferred, and more preferably 0.1 to 0.4 g.
/ Cm ³ . When the apparent density is less than 0.05 g / cm ³ , the uniform extensibility at the time of molding is inferior, and the
If it exceeds / cm ³ , it tends to adhere and fuse to the mold during molding, and may be poor in uniform spreadability. Furthermore, the basis weight of the microfiber nonwoven fabric is from 10 to 100 g /
m ² is preferable, and more preferably 20 to 80 g / m ^2.
m ² .

[0007] The thermoplastic synthetic fiber non-woven fabric used in the present invention is not particularly limited as long as it can be stretched by hot press molding. For example, a single or non-woven fabric such as polyester fiber, polyolefin fiber, polyamide fiber, conjugate fiber, and copolymer fiber can be used. A short fiber consisting of two or more, a long fiber or a mixed fiber thereof,
It can be obtained by a known method such as a spun bond method, a needle punch method, and a thermal bond method.

In the present invention, the average fiber diameter of the thermoplastic synthetic fiber nonwoven fabric is 10 to 100 μm, preferably 15 to 6 μm.
The range is 0 μm. The average fiber diameter of the nonwoven fabric is 10 μm
When the average fiber diameter exceeds 100 μm, the fiber gap becomes large and the prefilterability is poor. Further, the thermoplastic synthetic fiber nonwoven fabric preferably has a breaking elongation of at least 50% or more at a heating temperature when a pair of concave and convex molds are heated to 80 to 230 ° C. to perform molding, for example, and large deformation It is more preferable that the elongation at break is 100% or more when performing the stretching (forming) process. The basis weight of the thermoplastic synthetic fiber nonwoven fabric is 30 to 30 in terms of reinforcing property, pre-filtering property and the like.
0 g / m ² is preferable, and the apparent density is 0.1 to 0.6 g.
/ Cm ³ is preferred.

In the present invention , the container-like multilayer filter comprises:
For example, a thermoplastic synthetic fiber nonwoven fabric is laminated on one or both sides of a microfiber nonwoven fabric, and the laminate sheet is placed between a pair of heated and recessed molds and press-molded, or the laminate sheet is previously formed. After heating to the molding temperature,
It is obtained by integrally molding into a container having a flange portion and a molded portion extended from the flange portion by a method such as press molding with an uneven mold that has not been heated. The molding temperature is
It is appropriately selected depending on the shape of the container, the fiber material, and the like, but is usually performed at 80 to 230 ° C. The expansion ratio (depth / diameter) at the time of molding is usually 0.1 to 1.5.

[0010] In the present invention , the container-like multilayer filter comprises:
It is formed so that at least a part thereof is joined. For this purpose, for example, a method is employed in which a flange is formed into a linear shape or a dot shape in a mold so as to be fused at the time of molding. By joining at least a part of the laminated container-like multilayer filters, each nonwoven fabric can be handled as an integral body without being separated, so that the packing workability and the handleability as a filter product are improved.

The container-like multilayer filter obtained in this way can simultaneously obtain excellent filter performance using an ultra-fine fiber non-woven fabric and excellent moldability and shape retention properties using a thermoplastic synthetic fiber non-woven fabric. When the ultrafine fiber nonwoven fabric is formed by itself, problems such as easy fusion to a mold, heat shrinkage, and easy deformation are not caused.

[0012] the container-like multi-layer filter, to improve the liquid permeability when performing component extraction using liquid, it is possible to perform partial permeability processing. For example, a partially water-permeable container-like multilayer filter can be obtained by applying a water-permeable agent to a part of the bottom of the container-like multilayer filter by a spray method, a stamp method, or the like. The diameter of the container-shaped multilayer filter can be reinforced by using a plastic material.
For example, it is obtained by injection-molding a ring-shaped portion using a polypropylene resin in a filter diameter portion, and then performing hot press molding.

[0013]

The present invention will be described in more detail with reference to the following Examples, which should not be construed as limiting the invention thereto. Example 1 A propylene ultrafine fiber nonwoven fabric having an average fiber diameter of 2.0 μm, an apparent density of 0.12 g / cm ³ and a basis weight of 50 g / m ² was produced by a melt blow method. The average fiber diameter is 20 μm,
A polyester long-fiber nonwoven fabric having an apparent density of 0.33 g / cm ³ and a basis weight of 50 g / m ² was produced by a spun bond method. The breaking elongation at 120 ° C. of the obtained polyester filament nonwoven fabric was 250%.

Next, a cup-shaped concave / convex mold having a diameter of 65 mmφ and a depth of 50 mm is heated to a temperature of 120 ° C., and a polyester long-fiber nonwoven fabric is laminated on both surfaces of the ultrafine fiber nonwoven fabric and subjected to hot press molding. Was obtained (development ratio = 0.77). FIG. 1 shows a cross section of the container-shaped multilayer filter. In the figure, a container-shaped multilayer filter 5 comprises a flange portion 10 and a molded portion 11, and is constituted by thermoplastic synthetic fiber nonwoven fabrics 1, 3 and a microfiber nonwoven fabric 2. Reference numeral 4 denotes a joint between the thermoplastic synthetic fiber nonwoven fabrics 1 and 3 and the ultrafine fiber nonwoven fabric 1.

After applying a water-permeable agent to the inner surface of the bottom of the obtained container-shaped multilayer filter using a spray gun, coffee was extracted using the container-shaped multilayer filter as shown in FIG. In FIG. 2, the container-shaped multilayer filter 5 was placed on the upper part of the cup 6, the regular coffee powder 7 was put in the filter 5, and hot water 8 was poured to extract components. Hot water does not permeate from the side of the container-shaped multilayer filter,
Since the liquid was passed only from the bottom, the components could be sufficiently extracted. The extracted liquid 9 after the extraction was transparent with a good scent without leakage of the coffee powder 7.

Comparative Example 1 A container-shaped filter was obtained in the same manner as in Example 1, except that molding was performed using only the polyester long-fiber nonwoven fabric without using the propylene ultrafine fiber nonwoven fabric. When the components of the regular coffee powder were extracted in the same manner as in Example 1 using the obtained container filter, the powder leaked much and the extract was opaque and powdery.

Example 2 A propylene ultrafine fiber nonwoven fabric having an average fiber diameter of 1.6 μm, an apparent density of 0.16 g / cm ³ and a basis weight of 20 g / m ² was produced by a melt blow method. A polypropylene long-fiber nonwoven fabric having an average fiber diameter of 16 μm, an apparent density of 0.23 g / cm ³ and a basis weight of 100 g / m ² was produced by a spun bond method. 120 ° C of the obtained polypropylene long fiber nonwoven fabric
Was 130%. Next is 330mm
A concave and convex mold having a φ of 70 mm in depth (development ratio = 0.21) is heated to a temperature of 120 ° C., and a polypropylene long-fiber nonwoven fabric is laminated on one surface of the ultrafine fibrous nonwoven fabric. A container-shaped multilayer filter was obtained. After this container-shaped multilayer filter was subjected to electret processing, the filter performance was measured using stearic acid having a particle size of 0.3 μm. As a result, the collection efficiency was 82%, and it was confirmed that the air purification was excellent.

Comparative Example 2 In Example 2, a polypropylene long-fiber nonwoven fabric having an average fiber diameter of 16 μm, an apparent density of 0.23 g / cm ³ and a basis weight of 100 g / m ² was molded and processed in the same manner as in Example 2 to obtain a container. A filter was manufactured and the filter performance was measured in the same manner as in Example 2.
%, And the filter had low air purification.

[0019]

According to the production method of the present invention, since the integral molding using a laminate comprising a specific ultra-fine fibrous nonwoven fabric and a thermoplastic synthetic fibrous nonwoven fabric, moldability, filter performance, shape retention of the molded article A container-like multilayer filter having excellent properties, aeration / liquid permeability and handleability can be obtained . Therefore,
The container-shaped multilayer filter obtained by the present invention is particularly useful as an air filter for vacuum cleaners, air conditioners, automobiles, etc., a component extraction filter for green tea, black tea, regular coffee powder and the like, an oil strainer filter, and the like.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an example of a container-shaped multilayer filter of the present invention.

FIG. 2 is an explanatory cross-sectional view when the container-shaped multilayer filter of the present invention is used for component extraction.

[Explanation of symbols]

1, 3 ... thermoplastic synthetic fiber nonwoven fabric, 2 ... microfiber nonwoven fabric, 4 ... adhesive part, 5 ... container-shaped multilayer filter, 6 ... cup, 7 ... regular coffee powder (extractable), 8 ... hot water (for extraction) Liquid), 9 ... extract, 10 ... flange, 11
... Molding part.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-5-132869 (JP, A) JP-A-4-102415 (JP, A) JP-A-5-123260 (JP, A) JP-A-5-123260 189853 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) A47J 31/06 B32B 5/02

Claims (2)

(57) [Claims] 1. An ultrafine fiber nonwoven fabric having an average fiber diameter of 0.5 to 6.0 μm is provided on at least one surface with an average fiber diameter of 10 to 100 μm.
m thermoplastic synthetic fiber nonwoven fabric, and laminate
Hot press working using a mold, at least a part of the laminate is joined, and integrally molded into a container having a flange portion and a molded portion extended from the flange portion, A method for manufacturing a multilayer filter . 2. The apparent density of said ultrafine fiber nonwoven fabric is 0.5.
A 05~0.5g / c m ^3, producing side of the container-like multi-layer filter according to claim 1, wherein the elongation at break under the molding temperature of the thermoplastic synthetic fiber nonwoven fabric is 50% or more
Law.