JP2011089064A - Heat welding tape for filter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a filter in which the film-forming of a joint of a filter is prevented, and which is good-looking and is excellent in flexibility. <P>SOLUTION: Heat welding tape 102 for a filter joins two or more filter cloths 101, and the heat welding tape 102 is a fabric woven by multiple weavings, and is characterized in that a first tissue which surface-contacts filter cloth 101 comprises a fabric woven by using a bulky textured yarn made of a thermoplastic resin for at least one of a warp or weft, the bulky textured yarn is made to be exposed to adhesion surface 103 which surface-contacts the filter cloth, and the adhesion surface is made a surface rich in a cushioning property. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present invention relates to a heat welding tape for a filter that joins a plurality of filter cloths (hereinafter simply referred to as a welding tape). The welding tape of the present invention is suitably used, for example, for joining a bag filter for dust collection and a filter for a centrifugal separator.

In the present invention, multiple structures such as double weave and triple weave are used. The terminology used in this specification will be explained using a double tissue as an example. In the case of double weave, weft double weave, weft double weave, and warp double weave can be considered. In this specification, it counts from the side (adhesion surface) where a welding tape contacts a filter cloth (filter cloth), and is called a 1st structure | tissue and a 2nd structure | tissue. In the case of a double structure, the second structure is the outer surface of the welding tape. The second structure in this case is referred to as a surface structure (in the case of triple weaving, the third structure is the surface structure). In the case of weft double weave, the weft is double and the warp is single. In this case, the structure composed of the lower weft (weft) and the warp (warp) is referred to as the first structure, and the structure composed of the upper weft (weft) and the warp (warp) is referred to as the second structure.

A filter (filter medium) is used when filtering solid substances present in liquids and gases.

For example, Patent Document 1 discloses a filter cloth reversing centrifuge and a filter for separating a solid in a mixture of solid and liquid. Reference numeral 40 in FIG. 2 of the cited document 1 is a filter, and when centrifugal filtration is completed, the solid component remaining in the filter is inverted by inverting the filter as shown by the phantom line in FIG. To discharge from. In such a centrifuge, a bowl-shaped filter is used.

Patent Document 2 discloses a dust removing unit 5 for filtering dust in gas. Paragraph 23 of Patent Document 2 describes that the dust removing unit is a bag filter in which a plurality of filter cloth filters 7 of FIG. 1 are arranged.

Filters such as those disclosed in Patent Document 1 and Patent Document 2 are formed into a three-dimensional shape suitable for each application, such as a cylindrical shape or a bowl shape, by sewing a filter cloth cut into a predetermined shape.

At the filter cloth stitching site, the filter cloth ends are stitched together, or rolled up and stitched, so that filtration objects are likely to accumulate at the stitching site, and contamination (mixing of different types of filter objects or , And the growth of spoilage bacteria. In addition, when tension is applied to the filter, a needle hole at the stitching portion is opened, and there is a possibility that the filtration object leaks from there.

In order to solve this problem, the present inventors filled a sealing agent such as a hot-melt adhesive into a needle hole formed when sewing a filter cloth made of a synthetic fiber woven cloth into a three-dimensional shape. Attempts were made to solve the problems such as heating and melting the sewing portion of the filter, or laminating a thermoplastic resin film on the stitching portion and heating and melting, but none of the results were satisfactory.

In other words, the above method had no problem in terms of preventing the filtration target from leaking from the needle hole, but it was difficult to control the temperature and heat of the filter cloth itself and welding of the sealing agent, resin sheet, etc. When it became large, the problem that the fiber of a fusion | melting part became a film form arose. This not only looks bad as a filter, but also loses the flexibility of the filter at the film-like part, causing cracks when bent or pulled at that part, causing the filter to break became.

Japanese Patent No. 2998736 JP 2007-90226 A

An object of this invention is to provide the filter which does not have the possibility of producing a contamination without the leak of the filtration target object from the junction part of a filter. It is also an object of the present invention to provide a filter that prevents the joining portion of the filter from being formed into a film, has a good appearance, and has excellent flexibility.

The present inventors paid attention to a welding tape that is melted by heat. That is, the above-mentioned problem (leakage of the filtration target from the stitching point) can be solved by joining a plurality of filters with a welding tape or covering the stitches of the plurality of filters with a welding tape. It is.

However, when the thermoplastic resin sheet is used as a welding tape as it is, it is difficult to control the melting temperature of the tape, and the fabric constituting the filter is formed into a film as described above. Therefore, the inventors solved the problem of forming a film of the welding tape by configuring the welding tape so that the bulky processed yarn is exposed to the structure (adhesive surface) that contacts the filter with a multi-structured tape. It was.

That is, the present invention is a welding tape for a filter that joins a plurality of filter cloths, and the welding tape is a woven cloth woven by multiple weaving, and the first structure contacting the filter cloth is a warp. Alternatively, it consists of a woven fabric woven using bulky processed yarn made of thermoplastic resin for at least one of the weft yarns, and the bulky processed yarn is exposed on the adhesive surface in contact with the filter cloth and the adhesive surface is rich in cushioning properties It is a welding tape for a filter characterized by comprising as a flat surface. In the present invention, since the adhesive surface of the welding tape has cushioning properties, the adhesive surface absorbs the unevenness of the filter cloth to be joined, and the ends of the filter cloth are reliably joined at a lower temperature and in a shorter time than before. It becomes possible.

If the ratio at which the bulky processed yarn is exposed on the bonding surface is too small, the effect of absorbing the unevenness of the filter cannot be obtained. Therefore, the ratio at which the bulky processed yarn is exposed to the adhesive surface is preferably 40 to 100%, and more preferably 50 to 100%. If the bulky processed yarn is used for the warp and weft, the cost becomes high, so 60-80% is more preferable.

The ratio at which the bulky processed yarn is exposed on the adhesive surface can be appropriately determined depending on how the first structure is woven and whether the bulky processed yarn is used as a warp or weft. That is, in the case of plain weave, the exposure ratio is 50% or 100%, and in the case of 1/3 twill weave, it is 75% or 100% (see Example 2 and FIG. 5 described later).

On the other hand, the surface layer structure constituting the outer surface of the welding tape uses a filament yarn for at least one of the warp or the weft, the filament yarn is exposed on the outer surface, and the outer surface is configured as a smooth surface. This is preferable because the possibility of contamination due to the entry of an object can be reduced. A higher ratio of exposing the filament yarn on the outer surface is preferable from the viewpoints of cost reduction and prevention of remaining filtration target.

The filament yarn refers to a yarn having a higher density than the bulky processed yarn. It does not matter whether it is a monofilament or a multifilament. Moreover, said smooth surface means the state where the fiber was dense and cushioning property was small compared with the adhesion surface, and the touch was smooth. When the outer surface of the welding tape is formed as a smooth surface, there is no possibility that the filtration object remains in the fiber gap of the welding tape because the fibers are dense. In particular, when the welding tape is on the side in contact with the object to be filtered (the inside of the filter), it is preferable that the outer side of the welding tape is configured as a smooth surface.

Examples of the multiple weaving referred to in the present invention include double weaving such as weft double weaving, warp double weaving, and warp double weaving, and triple weaving such as weft triple weaving, warp triple weaving, and warp triple weaving. If it is multi-layered, the roles of the first structure serving as the adhesive surface and the surface layer structure serving as the outer surface of the welding tape can be shared. Therefore, in the present invention, the number of structures such as double structure and triple structure is not particularly limited. However, since the thickness of the welding tape can be reduced when the number of structures is small and the configuration is simple, it is preferable to have a double structure (double weave).

The present invention is characterized in that the bulky processed yarn is exposed on the back surface of the first structure serving as the adhesive surface of the filter. In the case of the weft double weave, the first structure and the second structure are composed of plain weaves. For example, both the weft (lower thread) and warp of the first structure are bulky processed yarns, and the weft (second upper structure) If the yarn is a filament yarn, the first structure may be composed only of the bulky processed yarn, and the surface of the second structure (the outer surface of the welding tape) may be composed of the filament yarn and the bulky processed yarn (ratio 1: 1). it can.

In warp double weave or weft double weave, the first structure is a woven fabric woven with twill or satin weave, and the other of the warp or weft constituting the first structure that is more exposed on the back The yarn may be a bulky processed yarn, and one of the yarns may be a filament yarn. For example, in a weft double weave, we adopt a structure other than plain weave that exposes a lot of warp on the surface of the structure, such as twill weave or satin weave for the first structure and twill weave (warp weave) or satin weave for the second structure. Then, a lot of wefts of the first structure are exposed on the back surface of the first structure (that is, the adhesive surface of the welding tape), and a large amount of warps are exposed on the surface of the second structure. In this case, a bulky processed yarn may be used for the first structure weft and a filament yarn may be used for the warp. On the contrary, when weaving twill weaving (yoko warrior weaving) or satin weaving that exposes a lot of wefts on the surface of the woven fabric, if bulky processed yarn is used for the warp, the bulky processed yarn is exposed on the back of the structure. Can do. Furthermore, when the first structure is a twill or satin weave and the second structure is a twill or satin weave, the relation between the warp and weft of the first structure of the weft double weave may be replaced (that is, The bulky processed yarn is used for the warp of the first structure).

In the present invention, the welding tape is configured as a woven fabric having multiple textures. This makes it possible to share roles in each organization and improve the performance of the welding tape. In the case of double weaving, the first structure functions as an adhesive layer. On the other hand, the second structure functions as a reinforcing layer. In other words, even if the first structure is melted, the fibers of the second structure are not melted and remain as fibers, and function as a flexible reinforcing layer. In contrast, when a woven fabric consisting of a single structure such as a plain woven fabric is used as the welding tape, the fiber melts and solidifies (films) by heating, and the function as the fiber is lost. The bonding strength of the tape will drop.

The bulky processed yarn of the present invention is a fiber imparted with crimpability. Appearance is shrunk like a perm, and has high elasticity and flexibility. The number of fibers constituting the bulky processed yarn, the production method, and the like are not particularly limited as long as the adhesive surface in contact with the filter cloth has a rough surface, that is, crimpability sufficient to provide sufficient cushioning properties. . For example, false twisted yarn can be mentioned as the bulky processed yarn of the present invention. The false twisted yarn is a yarn obtained by twisting a long fiber (twisting), heating (heat setting), and then crimping it in the opposite direction (untwisting).

When only the bulky processed yarn is used as the warp or weft, the yarn is not stiff and it may take time to weave. In such a case, the bulky processed yarn and the filament yarn may be twisted together to use the filament yarn as a so-called core material.

There are warp double weave, weft double weave and warp double weave in double weave. The same. However, since either the warp or the weft is single, the woven pattern of the first structure may affect the woven pattern of the second structure. On the other hand, in the warp double weave, since both the warp and the weft are double, the degree of freedom of the weaving pattern of the first structure and the second structure becomes high. For example, in a warp double weave or a warp triple weave, if the first structure is a plain weave using a bulky processed yarn for the weft and the surface structure is a plain weave using a filament yarn for the weft, the bonding surface is a bulky processed yarn. Only, and the outer surface of the welding tape can be composed only of filament yarns.

In terms of cost, in weft double weaving, weft yarns in the first structure are bulky processed yarns, weft yarns in the second structure are filament yarns with a higher density than bulky processed yarns, and filament yarns with high density are used as warps. The structure of weaving so that a large amount of weft is exposed on the adhesive surface and a large amount of warp is exposed on the outer surface of the welding tape is simple and advantageous (in the case of warp double weave, the warp and weft have the opposite relationship) . Which configuration is used may be determined according to the desired performance of the welding tape.

The bulky processed yarn of the present invention functions as an adhesive layer. Therefore, the material of the bulky processed yarn is not particularly limited as long as the ends of the filter cloth can be bonded to each other, but a preferable material is a thermoplastic resin. Examples of the thermoplastic resin suitably used in the present invention include polyolefins such as polyethylene and polypropylene, polyesters such as polyethylene terephthalate (PET), polyamides such as nylon 6 and nylon 66, polyphenylene sulfide (PPS), and the like. . In particular, PET is suitably used because it is available at low cost and has good welding performance (low bonding temperature and high bonding strength).

Filters that can be joined with the welding tape of the present invention include filters made of synthetic fibers such as polyethylene terephthalate (PET), polypropylene, nylon, and polyphenylene sulfide (PPS), filters made of natural fibers such as cotton and wool, and the like. Can be mentioned.

When joining a plurality of filter cloths with the welding tape of the present invention, the plurality of filter cloths may cover the portions stitched with the suture thread with the weld tape, or without being sewn with the suture thread. You may join the edge part of a filter cloth directly. When directly adhering with a welding tape, it is easy to adhere by heat-sealing the cloths between the filter cloths and temporarily fixing them.

In the present invention, since the welding tape is woven so that the bulky processed yarn is exposed on the bonding surface of the welding tape, the bonding surface of the welding tape can be made a flexible and cushioning surface. Accordingly, the unevenness of the plurality of filter cloths to be bonded can be absorbed by the cushioning property of the bonding surface, and the welding tape and the filter cloth can be brought into close contact with each other. As a result, a plurality of filter cloths can be joined with a smaller amount of heat than before.

In the present invention, the welding tape is woven by multiple weaving. As a result, the first structure can function as an adhesive layer, and the surface structure can function as a reinforcing layer. Therefore, the welding tape of the present invention does not have a possibility that the entire tape is turned into a film.

It is the schematic diagram which showed the filter to which the welding tape of this invention is applied. It is the figure which showed the organization chart and AA end surface of the welding tape of Example 1 (weft double weave). It is the organization chart which divided and showed the organization chart of the welding tape of Example 1 in the 2nd organization and the 1st organization. It is the figure which showed the organization chart and BB end surface of the welding tape of Example 2 (warp double weave, twill weave). It is the organization chart which divided and showed the organization chart of the welding tape of Example 2 to the 2nd organization and the 1st organization. It is the figure which showed the organization chart and B'-B 'end surface of the welding tape of Example 4 (warp double weave, satin weave). It is the organization chart which divided and showed the organization chart of the welding tape of Example 4 in the 2nd organization and the 1st organization. It is the figure which showed the organization chart and CC sectional drawing of the welding tape of Example 5 (weft double weave). It is the organization chart which divided and showed the organization chart of the welding tape of Example 5 in the 2nd organization and the 1st organization. It is the figure which showed the organization chart and DD cross section of the welding tape of Example 6 (wefting triple weave). It is the organization chart which divided and showed the organization chart of the welding tape of Example 6 in the 3rd organization, the 2nd organization, and the 1st organization. It is the schematic diagram which showed the joining method of the filter at the time of investigating the joining strength of the welding tape of this invention.

The present invention is a welding tape 102 for a filter that joins end portions of a plurality of filter cloths 101 (FIG. 1). The welding tape 102 is a woven fabric woven by multiple weaving, and the first structure in contact with the filter cloth 101 is woven using bulky processed yarn made of thermoplastic resin for at least one of warp or weft. It is made of a woven fabric formed, and the bulky processed yarn is exposed on the adhesive surface 103 in contact with the filter cloth 101 so that the adhesive surface 103 has a cushioning surface.

In addition, the outer surface 104 may be formed as a smooth surface by using a filament yarn for at least one of the warp or weft of the surface layer structure that becomes the outer surface 104 of the welding tape 102 of the present invention and exposing the filament yarn to the outer surface. Good.

For example, the welding tape shown in the following Example was produced as the welding tape of this invention. The following examples are merely examples, and the present invention is not limited to the following examples.

[Example 1]
The woven fabric constituting the welding tape 102 was woven with a weft double weave. The organization chart of the welding tape of this example and the AA cross section of the organization chart are shown in FIG. In the organization chart, the numbers in the X-axis direction indicate warp numbers, and the numbers in the Y-axis direction indicate weft numbers. The structure chart corresponds to the plane of the welding tape, and the frame filled with gray in the structure chart shows a state where the warp is on the weft (the state where the warp is floating). For example, the AA end surface of the organization chart of FIG. 2 is as shown in the lower part of FIG. The weft double weave is woven from the upper yarn (the first weft 21) and the lower yarn (the second weft 22) as the weft 2, and the warp 1. The upper yarn (the weft 21 of the first structure) constitutes the first structure together with the warp 1, and the lower thread (the weft 22 of the second structure) constitutes the second structure together with the warp 1 (see the AA end face in FIG. 2). ). For the convenience of drawing, the structure of the woven fabric is described in an end view excluding the depth.

FIG. 3 shows the organization chart of FIG. 2 divided into the first organization and the second organization. As is apparent from FIG. 3, in this example, the second structure of the welding tape was woven so that it became a 3/1 twill weave and the first structure became a 1/3 twill weave. 3 is a plan view, the majority (93.75%) of the bottom surface (adhesion surface of the welding tape) of the first structure of FIG. 3 is the state in which the weft 21 of the first structure is exposed. . Therefore, in this example, if a bulky processed yarn is used for the weft 21 of the first structure, the welded surface can be configured to have a cushion-rich surface.

In Example 1, a bulky processed yarn (one multifilament as a core material of PET 167 dtex and a multifilament of 167 dtex made of PET) was twisted into the weft 21 of the first structure and untwisted after heat setting. A multifilament consisting of two single filaments) was used. On the other hand, as the weft 22 and the warp 1 of the second structure, filament yarn (multifilament obtained by twisting 6 pieces of 84 dtex fibers made of PET) was used.

[Example 2]
The woven fabric constituting the welding tape 102 was woven with warp double weave. The organization chart of the welding tape of this example and the BB end surface of the organization chart are shown in FIG. The description method of the organization chart is the same as in the first embodiment. The warp double weave is woven from an upper yarn (second warp yarn 32), a lower yarn (first warp 31) and a weft 4 as the warp 3. The upper thread (second warp 32) constitutes the second structure together with the weft 4, and the lower thread (first structure warp 31) constitutes the first structure together with the weft 4 (see the end face BB in FIG. 4). ).

FIG. 5 shows the organization chart of FIG. 4 divided into the first organization and the second organization. As is apparent from FIG. 5, in this example, the second structure of the welding tape was woven so that it became a 3/1 twill weave and the first structure became a 1/3 twill weave. Since the structure diagram of FIG. 5 is a plan view, most (75%) of the bottom surface (bonding surface of the welding tape) of the first structure of FIG. 5 is in a state where the warp 31 of the first structure is exposed. Therefore, in this example, if a bulky processed yarn is used for the warp 31 of the first structure, the welded surface can be configured to have a cushioning property. In this example, bulky processed yarn was used for the warp 31 of the first structure, and filament yarn was used for the warp 32 and the weft 4 of the second structure. The configuration of the filament yarn was the same as that in Example 1, and a false twisted yarn made of 280 dtex multifilament made of PET was used as the bulky processed yarn.

[Example 3]
In the welding tape 102 of Example 1, a welding tape was produced in which both the upper yarn (weft yarn 22 of the second structure) and the lower yarn (weft yarn 21 of the first structure) were bulky processed yarns and the warp yarn 1 was a filament yarn. . The configuration of the bulky processed yarn and filament was the same as in Example 1.

[Example 4]
The woven fabric constituting the welding tape 102 was woven with warp double weave. The organization chart of the welding tape of this example and the end face B'-B 'of the organization chart are shown in FIG. The description method of the organization chart is the same as in the first embodiment. The warp double weave of this embodiment is woven from an upper thread (second warp 32 '), a lower thread (first warp 31') and a weft 4 'as warp 3'. The upper yarn (second warp 32 ') constitutes the second structure together with the weft 4', and the lower yarn (first warp 31 ') constitutes the first structure together with the weft 4' (B in FIG. 6). '-B' end surface reference).

FIG. 7 shows the organization chart of FIG. 6 divided into the first organization and the second organization. As is apparent from FIG. 7, in this example, the second structure and the first structure of the welding tape were woven so as to form a five-sheet satin weave (the number of jumps was 3). Since the organization chart of FIG. 7 is a plan view, most (80%) of the bottom surface (bonding surface of the welding tape) of the first organization of FIG. 7 is in a state where the warp 31 'of the first organization is exposed. Therefore, in this example, if a bulky processed yarn is used for the warp 31 'of the first structure, the welded surface can be configured to have a cushion-rich surface. In this example, bulky processed yarn was used for the warp 31 'of the first structure, and filament yarn was used for the warp 32' and the weft 4 'of the second structure. The configuration of the bulky processed yarn and the filament yarn was the same as in Example 1.

[Example 5]
The woven fabric constituting the welding tape 102 was woven with a double weave. FIG. 8 shows a structure diagram of the welding tape of this example and a CC cross section of the structure chart. The description method of the organization chart is the same as in the first embodiment. A white circle in the organization chart of FIG. 8 indicates a connection point 63 between the first organization and the second organization.

FIG. 9 shows the organization chart of FIG. 8 divided into the first organization and the second organization. As is apparent from FIG. 9, in this example, the first structure and the second structure of the welding tape were both woven so as to form a plain weave. The bottom surface (adhesion surface of the welding tape) of the first structure in FIG. 9 is a state where the wefts 61 of the first structure and the warp threads 51 of the first structure are alternately exposed. Therefore, in this example, if a bulky processed yarn is used for at least one of the first structure weft 61 (ie, even-numbered weft) and the first structure warp 51 (ie, even-numbered warp), the bonding surface is cushioned. It is possible to construct a surface rich in properties (exposure rate of bulky processed yarn is 100%).

In Example 5, bulky processed yarns are used for both the weft 61 of the first structure and the warp 51 of the first structure, and both the weft 62 (odd numbered weft) of the second structure and the warp 52 of the second structure are used. Filament yarn was used. All other yarns were filament yarns. The configuration of the bulky processed yarn and the filament yarn was the same as in Example 1.

[Example 6]
The welding tape 102 was woven with a triple weave. The organization chart of the welding tape of this example and the DD cross section of the organization chart are shown in FIG. The description method of the organization chart is the same as in the first embodiment. As shown in the DD cross section of FIG. 10, the first and fourth warps (third warp 73) and the third weft 83 form a third structure, and the second and fifth warps. The second structure is formed by the second structure warp 72 and the second structure weft 82, and the first structure is formed by the sixth and third warps (first structure warp 71) and the first structure weft 81. Formed. No. 7 and No. 8 warp yarns (binding yarn 74) were used to bind the first structure, the second structure, and the third structure.

FIG. 11 shows the organization chart of FIG. 10 divided into the first organization, the second organization, and the third organization. As is clear from FIG. 11, in this example, the first structure, the second structure, and the third structure of the welding tape were woven so as to be a plain weave. The bottom surface of the first structure in FIG. 11 (adhesion surface of the welding tape) is a first structure weft 81 (that is, a weft having a number that is a multiple of 3) and a first structure warp 71 (that is, a number that is a multiple of 3). Are alternately exposed (see FIGS. 10 and 11). Therefore, in this example, if a bulky processed yarn is used for at least one of the first structure weft 81 and the first structure warp 71, the adhesive surface can be configured to have a cushion-rich surface (the bulky processed yarn of (Exposure rate is 100%).

In Example 6, bulky processed yarns are used for both the first structure weft 81 and the first structure warp 71, the second structure weft 82, the second structure warp 72, the third structure weft 83 and the first structure. Filament yarn was used for the warp 73 having three textures. All other yarns were filament yarns. The configuration of the bulky processed yarn and the filament yarn was the same as in Example 1.

[Comparative Example 1]
Using a filament yarn having the same configuration as in Example 1 as a warp and a weft, a single welding tape was produced with 2/3 twill (not shown).

[Comparative Example 2]
Using a bulky processed yarn having the same configuration as in Example 1 as warp and weft, a single welding tape was produced with five satin weaves (not shown).

The structures of the welding tapes of Examples 1 to 6 and Comparative Examples 1 and 2 are summarized in Table 1.

Using the welding tapes of Examples 1 to 6 and Comparative Examples 1 and 2, the ends of the filter cloth were joined together. As the material of the fiber constituting the filter cloth, PET fiber, nylon 6 fiber, wool fiber, PPS fiber, and PET short fiber (nonwoven fabric) were used. The structure of the filter cloth is as summarized below, but a woven cloth having a surface shape rich in irregularities that is difficult to be joined by a conventional welding tape. As shown in FIG. 10, the welding operation is performed by temporarily fixing the ends of two similar types of filter cloths 101 with temporary retaining yarns 105, and Examples 1 to 6 on the joint part of the two filter cloths. The welding tapes 102 of Comparative Examples 1 and 2 were applied and welded using a welding machine manufactured by Quinlight Electronics (QHP-A08). This welding machine is a system in which hot air is sent between the welding tape 102 and the filter cloth 101 to melt the adhesive surface 103 of the tape and press-bond with a roller from above the tape, so that it is not affected by the thickness of the tape. It is possible to weld a tape. The welding conditions are as follows. After welding, the end 106 of the filter sewn with the temporary thread 105 was cut off. The filter 101 joined with the welding tape 102 was pulled from above and below, and the joining strength at the joint and the change in the welding tape were evaluated. The results are summarized in Table 2.
1. Conditions for welding work Temperature setting: 410 ° C
Welding speed: 1 m / min Roll pressure: 0.4 MPa
2. Filter (filter cloth) composition warp 1100 dtex multifilament weft 1100 dtex multifilament warp material Weaving methods listed in Table 2 2/2 twill

Filters marked with circles in Table 2 can be welded at 410 ° C. and have sufficient bonding strength (although it varies somewhat depending on the material of the filter and the ratio of the exposed bulky thread on the adhesive surface of the welding tape, the bonding strength is 30 to 30%. 80 daN), and the welding tape was kept flexible without forming a film. It was confirmed that the bonding strength tends to increase as the ratio of the exposed bulky processed yarn to the bonded surface increases. Although the triangle mark could be welded at 410 ° C., the welding tape was partially formed into a film. When the upper and lower filters of the joined portion were pulled, the welding tape was broken and the filter was easily broken from the joined portion. The filter with a cross was not able to join the end portions of the filter at 410 ° C. When the welding temperature was raised to 480 ° C., the ends of the filters could be joined to each other, but the welding tape was completely filmed and lost its flexibility. In addition, the joint filter was partially burnt.

Next, in the welding tape of Example 1 and the welding tape of Example 5, all of the first structure weft 61, the first structure warp 51, the second structure weft 62, and the second structure warp 52 are processed to be bulky. The calcium carbonate suspension was subjected to centrifugal filtration using a PET filter joined using a welding tape constructed as described above (hereinafter referred to as Example 7) as a filter of a centrifuge. As calcium carbonate, Calcium Softon 1000 (average particle size 2.2 μm) of Bihoku Flour Industry Co., Ltd. was used. The filter was used in the centrifuge of Patent Document 1 such that the welding tape of the filter was on the suspension side.

Regarding the filtrate after centrifugal filtration, leakage of calcium carbonate particles was verified by absorbance analysis. In both Examples 1 and 7, there was almost no particle leakage.

Thereafter, the filter was inverted as shown in FIG. 2 of Patent Document 1 to clean the filter. In Example 1, since the joining portion is a welding tape, the particles of the calcium carbonate do not remain in the deepened portion of the stitched portion, unlike the conventional stitched filter, and the cleaning can be easily completed. . In addition, since the surface of the welding tape was a smooth surface, the calcium carbonate particles did not stick to the surface of the welding tape, and the calcium carbonate particles could be easily removed. Further, the durability of the joint portion of the filter with the welding tape was sufficient, and it did not break even after repeated use for a long period of time.

On the other hand, in the filter using the welding tape of Example 7, the bulky processed yarn used for the wefts of the second structure is exposed on the surface of the welding tape, and the calcium carbonate particles are stuck on the surface, and it takes time to remove. Cost. Similar to the filter of Example 1, the strength of the joined portion of the filter was sufficient.

As described above, the present invention can enhance the adhesion to the filter by exposing a large amount of bulky processed yarn on the adhesive surface of the welding tape. Moreover, by making the surface of the welding tape a smooth surface, the filter can be easily cleaned and the risk of contamination can be minimized.

1 Warp (double weave)
2 Weft (weft double weave)
21 Weft of the first structure (double weave / twill)
22 Weft of second structure (weft double weave / twill weave)
3 Warp (warp double / weave)
31 Warp of the first structure (warp double / weave)
32 Warp yarn of second structure (warp double / weave)
4 Weft (warp double / weave)
3 'warp (warp double weave / satin weave)
31 'Warp of the first structure (warp double weave / satin weave)
32 'Warp of second structure (warp double weave / satin weave)
4 'weft (warp double weave / satin weave)
5 Warp (double weaving warp)
51 Warp of the first structure (warp weave / plain weave)
52 Warp yarn of the second structure (double weft / plain weave)
6 Weft (double weft warp)
61 Weft of the first structure (double weft / plain weave)
62 Weft yarn of the second structure (warp double weave / plain weave)
63 Knotting point 7 Warp
71 Warp yarn of the first structure
72 Warp yarn of the second structure
73 Third organization warp (wefting triple weave / plain weave)
74 Binding yarn 8 Weft
81 Weft of the first structure (Wraft triple weave / plain weave)
82 Weft yarn of the second structure (warp weave / plain weave)
83 Weft of the third structure
DESCRIPTION OF SYMBOLS 101 Filter cloth 102 Welding tape 103 Adhesive surface 104 Outer surface 105 Suspension thread 106 End of filter

Claims (4)

A heat welding tape for a filter that joins a plurality of filter cloths,
The heat-welding tape is a woven fabric woven by multiple weaving, and the first structure contacting the filter fabric is woven using bulky processed yarn made of thermoplastic resin for at least one of warp or weft. A heat-sealing tape for a filter, comprising a woven fabric, wherein the bulky processed yarn is exposed on an adhesive surface in contact with the filter fabric, and the adhesive surface is configured as a cushion-rich surface. The surface layer structure constituting the outer surface of the heat-welded tape woven by multiple weaving uses a filament yarn for at least one of warp or weft, and the outer surface is configured to be a smooth surface by exposing the filament yarn to the outer surface. The heat welding tape for filters according to claim 1. The heat-welding tape is a woven fabric woven with warp double weft or weft double woven, and the first structure is a woven cloth woven with twill or satin weave and constitutes the first structure. The heat-welding tape for a filter according to claim 2, wherein one of the warp or weft to be exposed is a bulky processed yarn, and the other yarn is a filament yarn. The heat welding tape is a woven fabric woven with a weft double weave or a weft triple woven, and the first structure is a structure woven with a plain weave, and both the wefts constituting the first structure. The heat welding tape for a filter according to claim 2, wherein a bulky processed yarn is used and the surface layer structure is a structure woven in a plain weave, and filament yarns are used for both warp and weft yarns constituting the surface layer structure.

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