JP2017166091A - Planar structure and manufacturing and application methods thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flexible and highly durable planar structure that can be used as an adsorptive plate for a vacuum adsorptive device or a filter and has air permeability required for these applications.SOLUTION: A planar structure is made of nonwoven fabric and has one or more ventilation part(s) and one or more encapsulation part(s) with lower ventilation volume than the ventilation part in a plane. HDD of the ventilation part is 13 or higher and 45 or less. HDD of the encapsulation part is preferably 65 or higher and 85 or less.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a suction plate for a vacuum suction device, a planar structure that can be used as a filter, and a method for manufacturing and using the same.

The suction plate used in the vacuum suction device sucks air from the vacuum port and puts it in a vacuum state to suck and transport workpieces such as films, glass substrates, silicon wafers, etc. Processing. Therefore, if air leaks from the side surface of the suction plate when air is sucked, the suction force is insufficient, the work fixing force is inferior, and it is difficult to perform precise machining. In order to cope with this problem, a method has been proposed in which an airtight material such as a film or a resin is disposed on the outer peripheral portion of the suction plate to form a sealing portion to suppress air leakage. On the other hand, when a flexible work such as a thin film is transported, if there is uneven suction on the work, suction marks remain on the work, so it is widely used these days to suck air uniformly. Many fine holes are formed on the suction surface of the suction plate.
As such suction plates, the suction plates described in Patent Documents 1 to 7 are known. Patent Documents 1 to 5 disclose a suction plate in which a suction surface is formed of a flexible material such as sponge or rubber, or a porous material obtained by sintering a resin. Yes. Patent Documents 6 to 7 disclose a suction plate made of nonwoven fabric.

  On the other hand, as with the suction plate, a material that requires a certain level of air permeability is a filter. When a filter is mounted on a filtration device, it is usually mounted by forming a frame on the outer periphery after folding an air-permeable material into a bellows shape. In recent years, various filter materials using the same material as the frame and the air-permeable material have been proposed in consideration of environmental burdens. As a method for manufacturing such a filter, Patent Document 8 discloses a bellows for the air-permeable material. A method of performing processing and frame formation in one step has been proposed.

JP 2002-127067 A JP-A-8-169971 JP-A-6-71854 JP 2004-59295 A JP 2005-28506 A JP 2012-61556 A Utility Model Registration No. 3164417 JP 2002-126422 A

  However, in the suction plates described in Patent Documents 1 to 5, although the sponge and the rubber material are excellent in air permeability and flexibility, there are problems such as poor wear resistance and durability. In addition, although the sintered body is excellent in wear resistance, it is hard and has a rough surface, so that the surface must be mirror-polished in order to make the eyes finer, which increases the manufacturing cost of the suction plate. Moreover, in the suction plate of patent documents 6-7, thickness tends to become thin as the frequency | count of suction | increase increases, and there exists a problem in terms of durability, and the dimensional shift between the laminated nonwoven fabrics by long-term use. In some cases, it was wrinkled. Further, in recent years, the shape of the suction plate is mainly a plate having a uniform thickness. Therefore, the suction plates of Patent Documents 6 to 7 are required to be improved in terms of the shape.

  Also, in filter applications, filter materials having various shapes have been required in recent years depending on the application, and a filter having a new shape is required in addition to the filter material of Patent Document 8 in which only the brim is pressed. .

  An object of the present invention is to provide an adsorption plate for a vacuum adsorption device, a planar structure that can be used as a filter, is flexible and excellent in durability, and has air permeability required for these applications, and the planar structure. An object of the present invention is to provide a production method capable of providing a structure more simply.

As a result of intensive studies to solve the above problems, the present inventors have found that the durability of the suction plate is affected by the hardness of the ventilation portion. Accordingly, an object of the planar structure according to the present invention is to improve the durability of the suction plate by controlling the hardness of the ventilation portion within a certain range.
The present inventors also laminated a non-woven fabric having a low-melting fiber and having a cut-out portion and a non-woven fabric having a low-melting-point fiber and not having a cut-out portion as a method for producing the planar structure. By applying hot pressing to the surface of this nonwoven fabric laminate, the ventilation volume and hardness of the ventilation part can be controlled within a predetermined range, and the sealing part (frame) can be formed while smoothening the surface of the fiber structure. The present invention was completed by finding that it can be easily formed by a single operation.

That is, the present invention is as follows.
[1] A planar structure composed of a nonwoven fabric,
And having in the surface both one or more ventilation portions and one or more sealing portions having a lower air flow rate than the ventilation portions,
The planar structure is characterized in that the HDD of the ventilation section is 13 or more and 45 or less.
[2] The planar structure according to [1], wherein the HDD of the sealing portion is 65 to 85.
[3] The ventilation rate of the ventilation part is 20 cm ³ / cm ² · sec or more and 250 cm ³ / cm ² · sec or less, and the ventilation rate of the sealing part is 0 cm ³ / cm ² · sec or more and 10 cm ³ / cm ² · sec. The planar structure according to [1] or [2], which is the following.
[4] The planar structure according to [1] to [3], wherein the thickness of the ventilation portion is 0.8 to 1.05 times the thickness of the sealing portion.
[5] The planar structure according to [1] to [4], wherein a weight ratio of the ventilation part to the sealing part (venting part / sealing part) is 0.05 or more and 0.70 or less.
[6] the density of the vent is at 0.15 g / cm ³ or more 0.50 g / cm ³ or less, the density of the sealing portion is not more than 0.50 g / cm ³ or more 1.50 g / cm ³ [1] -Planar structure as described in [5].
[7] The planar structure according to [1] to [6], wherein low melting point fibers having a melting point of 80 ° C. or higher and 220 ° C. or lower are present on the surface of the planar structure in a melted and solidified state.
[8] An adsorption plate for vacuum adsorption method including the planar structure according to [1] to [7].
[9] A filter comprising the planar structure according to [1] to [7].
[10] A non-woven fabric laminate obtained by laminating a non-woven fabric for middle material (a1) having a low melting point fiber and having a cut-out portion and a non-woven fabric for middle material (a2) having a low melting point fiber and having no cut-out portion Producing (a), and
A method for producing a planar structure comprising the step of compressing the nonwoven fabric laminate (a) into a planar shape in the thickness direction while bringing at least one surface of the nonwoven fabric laminate (a) into contact with a heated mold.
[11] At least one of the non-woven fabric for intermediate material (a1) having the cutout portion and the non-woven fabric for intermediate material (a2) having the cutout portion is a non-heat-bondable fiber having a melting point higher than that of the low-melting fiber. The manufacturing method of the planar structure as described in [10].
[12] The basis weight of the nonwoven fabric for middle material (a1) having a cutout portion is 30 g / m ² or more and 200 g / m ² or less, and the number of laminated layers is 3 or more and 50 or less,
[10] or [11] according to [10] or [11], wherein the weight of the nonwoven fabric for intermediate material (a2) having no cut-out portion is 30 g / m ² or more and 200 g / m ² or less and the number of laminated layers is 1 or more and 30 or less. Manufacturing method of structure.
[13] The non-woven fabric laminate (a) includes a cut-out structure portion composed of 1 to 5 non-woven fabrics for middle materials (a1) having the cut-out portions, and a non-woven fabric for intermediate materials (not having the cut-out portions). a2) a non-cutout structure part composed of 1 to 5 sheets,
The method for producing a planar structure according to [10] to [12], wherein three or more cutout structure portions and non-cutout structure portions are alternately laminated.
[14] The method for producing a planar structure according to [10] to [13], wherein a nonwoven fabric for a surface material is laminated as an outermost layer of the nonwoven fabric laminate (a).
[15] The method for producing a planar structure according to [14], wherein the total mass of the low melting point fibers is 80% by mass or more in 100% by mass of the nonwoven fabric for surface material.

  ADVANTAGE OF THE INVENTION According to this invention, the planar structure which is flexible and excellent in durability, and has the air permeability required for the said use, and the manufacturing method which can provide this planar structure more simply are provided.

It is a schematic perspective view of the planar structure which concerns on this invention. It is a reference figure showing typically the manufacturing method of the planar structure concerning the present invention. It is the schematic which shows the one aspect | mode of the usage method of the planar structure which concerns on this invention. 2 is an enlarged photograph (100 times) of a planar structure obtained in Example 2. FIG. It is an enlarged photograph (100 times) of the adsorption | suction plate used in the comparative example 4.

<Surface structure>
FIG. 1 shows a schematic perspective view of a planar structure according to the present invention. The planar structure 1 is made of non-woven fabric, and includes one or more ventilation portions 2 and one or more sealing portions 3 having a lower air flow rate than the ventilation portions 2. Each ventilation portion 2 is preferably surrounded by the sealing portion 3 on the entire circumference, and becomes a suction portion when a workpiece is lifted by a vacuum suction method. Moreover, the ventilation | gas_flowing part 2 becomes a filtration part of a filter. On the other hand, the sealing portion 3 exhibits a function of preventing air leakage when the workpiece is lifted by a vacuum suction method, and also functions as a filter frame.

  The planar structure according to the present invention is easy to manufacture the planar structure, the planar structure has an appropriate flexibility, and can suppress variations in suction force in the vacuum suction device. It is formed from a nonwoven fabric. FIG. 4A shows an enlarged photograph of the planar structure (Product of Example 2) according to the present invention. On the other hand, FIG. 4B shows an enlarged photograph of a suction plate (comparative example 4) made of a conventional sintered body. As apparent from FIG. 4 (a), since the product of the present invention is composed of a nonwoven fabric, the fibers are randomly arranged three-dimensionally on the surface of the planar structure, and the fineness of the eyes on the surface is reduced. Can be maintained. Comparing FIG. 4 (a) and FIG. 4 (b), it can be seen that the product of the present invention has many smaller gaps than the suction plate made of a sintered body. The large number of small gaps makes it possible to arrange the air flow path during suction in the vacuum suction device while maintaining a high air flow rate, thereby suppressing variations in suction force. For this reason, the product of the present invention has an advantage that wrinkles and suction marks are hardly attached even if the suction force in the vacuum suction device is increased.

As described later, the planar structure is preferably produced by subjecting a nonwoven fabric laminate obtained by laminating a plurality of nonwoven fabrics having low melting point fibers to a planar (particularly entire surface) hot pressing. Therefore, it is preferable that low melting point fibers having a melting point of 80 ° C. or higher and 220 ° C. or lower are present on the surface of the planar structure in a melted and solidified state. The low melting point fiber after heat melting on the surface of the planar structure follows the mold of the hot press machine in the melted state due to the pressure during the hot pressing, so the low melting point fiber cooled and solidified has the planar structure. Contributes to smoothing the body surface. Furthermore, since the low melting point fiber after heat melting is solidified in a state where the entanglement point of the fiber is fixed, it contributes to the improvement of the hardness in the ventilation part and the sealing part.
The area of the low-melting fiber after heat melting (melt-solidified portion area) is preferably 30 area% or more, more preferably 50 area% or more, and further preferably 70 area%, in the total area of the front and back surfaces of the planar structure 100 area%. As mentioned above, it is still more preferably 90 area% or more, particularly preferably 100 area%, but it may be 95 area% or less.
Further, by observing the molten state of the low melting point fiber on the surface of the planar structure, it is possible to know the area that has been hot pressed into a planar shape. The area of the region hot-pressed into a planar shape is preferably 50 area% or more, more preferably 70 area% or more, and may be 100 area%, in a total area of 100 area% of the front and back surfaces of the planar structure. Moreover, 90 area% or less may be sufficient and 80 area% or less may be sufficient. In addition, a plurality of planar hot press regions may exist independently from each other on the front surface or the back surface (that is, a non-press region exists, and a plurality of planar hot press regions are separated by this non-press region. Also good). However, when a plurality of planar hot press regions are present independently, at least one ventilating portion 2 having the entire periphery surrounded by the sealing portion 3 is present in at least one planar hot press region.
Although the low-melting fiber is present in a melted and solidified state in the planar structure, depending on the processing conditions during hot pressing, the low-melting fiber and fibers other than the low-melting fiber may remain unmelted.

1. Ventilation part In this invention, the hardness (HDD) of the said ventilation part shall be 13-45. For example, the HDD of the planar structure manufactured in the example of Patent Document 6 is about 5 to 13. However, when the HDD of the ventilation section is less than 13, the ventilation section tends to be sluggish due to long-term use, and it tends to become thin within a short period of time. From the viewpoint of improving the suction plate replacement cycle, the ventilation section HDD Is 13 or more. In general, the sintered porous material HDD is about 50 to 100 as the suction plate. However, if the HDD of the ventilation part exceeds 45, it is too hard as the suction plate, so a flexible work such as glass or thin film can be used. When adsorbed, it is not preferable because the workpiece may be damaged by coming into contact with the ventilation portion. The HDD of the ventilation section is 13 or more, more preferably 15 or more, further preferably 17 or more and 45 or less, more preferably 40 or less, and still more preferably 35 or less.

In order to improve the lift force and the filter performance by the vacuum adsorption method, the air flow rate in the ventilation part is preferably 20 cm ³ / cm ² · sec or more, more preferably 23 cm ³ / cm ² · sec or more, and further preferably 25 cm ³ / cm. ² · sec or more, preferably 250 cm ³ / cm ² · sec or less, more preferably 140 cm ³ / cm ² · sec or less, and further preferably 130 cm ³ / cm ² · sec or less. The air flow can be adjusted according to the use of the suction plate and the filter.

  Since the planar structure is composed of non-woven fabric, there are fibers and fiber-derived substances in the planar structure, but from the viewpoint of improving air permeability, there is an intertwined state of fibers particularly in the ventilation portion. It is desirable.

  When used as a suction plate, the thickness of the ventilation portion is preferably 0.5 mm or more, more preferably 0.8 mm or more, still more preferably 1.0 mm or more, preferably 6.0 mm or less, more preferably 5. 0 mm or less, more preferably 3.0 mm or less. When used as a filter, it is preferably 1 mm or more, more preferably 1.5 mm or more, still more preferably 2.0 mm or more, preferably 20 mm or less, more preferably 15 mm. Hereinafter, it is more preferably 10 mm or less. By adjusting the thickness of the ventilation portion within the above range, the durability of the planar structure is improved, and the lifetime of the suction plate and the filter can be extended.

The basis weight of the ventilation portion is preferably 150 g / m ² or more, more preferably 250 g / m ² or more, still more preferably 300 g / m ² or more, preferably 3000 g / m ² or less, more preferably 1200 g / m ² or less. More preferably, it is 1050 g / m ² or less. By adjusting the basis weight of the ventilation portion within the above range, the durability of the planar structure is improved and the life of the suction plate can be extended.

In general, the density (apparent specific gravity) of the porous material used for the adsorption plate is about 1.2 to 3.0 g / cm ³ , but the density of the ventilation part is preferable for reducing the weight of the adsorption plate and the filter. is 0.15 g / cm ³ or more, more preferably 0.22 g / cm ³ or more, still more preferably 0.28 g / cm ³ or higher, preferably 0.50 g / cm ³ or less, more preferably 0.48 g / cm ³ or less, more preferably 0.45 g / cm ³ or less.

  The shape of the ventilation portion can be freely selected from a circle, a triangle, a quadrangle, a pentagon or more polygon, a donut shape, and the like.

  It is desirable that the ratio of the ventilation portion to the entire planar structure is adjusted to an appropriate range so that the workpiece can be reliably adsorbed. The ventilation part is preferably 5 area% or more, more preferably 10 area% or more, preferably 95 area% or less, more preferably 80 area% or less, in 100 area% of the area (one side) of the planar structure.

  In the planar structure, one or more ventilation portions exist, but when two or more ventilation portions exist, these two or more ventilation portions exist discontinuously in the planar structure. In these two or more ventilation portions, the ventilation amount and shape may be the same or different.

2. Sealing portion Since the sealing portion has a lower air flow rate than the ventilation portion, the air flow rate of the sealing portion is preferably 10 cm ³ / cm ² · sec or less, more preferably 5 cm ³ / cm ² · sec. Hereinafter, it is more preferably 2.5 cm ³ / cm ² · sec or less. Although not the lower limit of the air permeability of the sealing portion is particularly limited, aeration of the sealing portion is usually at 0.03cm ³ / cm ² · sec or more, preferably 0cm ³ / cm ² · sec It is. If the air flow rate of the sealing part is within the above range, air leakage can be suppressed in the vacuum adsorption method. The air flow can be adjusted according to the use of the suction plate and the filter.

  Since the planar structure is composed of a nonwoven fabric, the raw nonwoven fabric has a fiber entangled state. From the viewpoint of reducing the air flow rate of the sealing portion, the sealing portion is formed by the fiber entanglement in particular. It is desirable that the micropores to be compressed are filled.

  The hardness of the sealing part can be adjusted according to the actual specification. For example, the HDD of the sealing part is preferably 65 or more, more preferably 68 or more, further preferably 72 or more, preferably 85 or less. More preferably, it is 80 or less, More preferably, it is 79 or less. If the HDD of the sealing part is within the above range, both the suction plate and the filter frame satisfy the hardness required for each product.

  When used as a suction plate, the thickness of the sealing part is preferably 0.5 mm or more, more preferably 0.8 mm or more, still more preferably 1.0 mm or more, preferably 6.0 mm or less, more preferably Is 5.0 mm or less, more preferably 3.0 mm or less. By adjusting the thickness of the sealing portion within the above range, the effect of suppressing air leakage is sufficiently exhibited. When used as a filter, the thickness of the sealing portion is preferably 1 mm or more, more preferably 1.5 mm or more, still more preferably 2.0 mm or more, preferably 20 mm or less, more preferably 15 mm or less, and even more preferably. Is 10 mm or less.

Basis weight of the sealing portion, preferably 500 g / m ² or more, more preferably 1050 g / m ² or more, further preferably 1200 g / m ² or more, preferably 10000 g / m ² or less, more preferably 3500 g / m ² Hereinafter, it is more preferably 3000 g / m ² or less. By adjusting the basis weight of the sealing portion within the above range, the effect of preventing air leakage is sufficiently exhibited in the use of the suction plate, and the strength as a frame material is secured in the use of the filter.

In order to reduce the weight of the adsorption plate and filter, the density of the sealing portion is preferably 0.50 g / cm ³ or more, more preferably 0.60 g / cm ³ or more, and further preferably 0.85 g / cm ³ or more. There, preferably 1.50 g / cm ³ or less, more preferably 1.35 g / cm ³ or less, further preferably 1.20 g / cm ³ or less.

  From the viewpoint of enhancing the adsorptivity of the workpiece, it is preferable that the outer peripheral portion of the planar structure is mainly composed of a sealing portion. “The outer peripheral portion of the planar structure is mainly constituted by the sealing portion” means that the sealing portion is preferably 80% or more, more preferably 85% or more, further, with respect to the entire circumference of the planar structure. Preferably, it is 90% or more, more preferably 95% or more, and particularly preferably 100% (that is, the sealing part is present as a frame of the planar structure and the ventilation part is present in the frame). It means that it exists. With this configuration, air leakage from the side portion of the planar structure can be suppressed at a high level.

3. Planar structure In the planar structure, the nonwoven fabric used as a raw material is compressed in the thickness direction by planar (particularly the entire surface) hot pressing, and the surface of the planar structure is smoothed by this operation. There is almost no difference in thickness between the part and the sealing part. That is, the thickness of the ventilation portion is preferably 0.8 times or more, more preferably 0.85 times or more, still more preferably 0.90 times or more, and still more preferably 0 times the thickness of the sealing portion. 0.95 times or more, preferably 1.05 times or less, more preferably 0.99 times or less, and still more preferably 0.98 times or less. By adjusting the thickness of the ventilation part and the sealing part within the above range, it becomes easier to attach the suction part to the vacuum suction device as a suction plate, and compared with the suction plate described in Patent Documents 6 to 7, Air leakage can be suppressed at a high level.

  It is desirable to reduce the basis weight of the ventilation part and increase the ventilation rate so that the workpiece can be reliably adsorbed. On the other hand, when adsorbing a workpiece, it is necessary to reduce the air flow rate of the sealing portion to make it difficult for air to leak, so that the basis weight of the sealing portion is preferably large. From such a viewpoint, the ratio of the basis weight of the ventilation part to the sealing part (ventilation part / sealing part) is preferably 0.70 or less, more preferably 0.6 or less, still more preferably 0.5 or less, particularly Preferably it is 0.4 or less. The lower limit is not particularly limited, but the ratio of the basis weight of the ventilation part to the sealing part may be 0.05 or more, preferably 0.1 or more, or 0.15 or more. In Patent Documents 6 to 7, since there is no cut-out portion in the raw material nonwoven fabric, when the entire surface of the raw nonwoven fabric laminate is hot-pressed, there is no difference in breathability in the nonwoven fabric after hot pressing. Thus, the ventilation part and the sealing part cannot be made separately. However, in the present invention, a nonwoven fabric having a cut-out portion and a nonwoven fabric not having a cut-out portion are used as raw materials. Therefore, when a sheet (particularly the entire surface) is hot-pressed on the raw-material nonwoven fabric laminate, It is possible to separately create a ventilation portion and a sealing portion having different air permeability while keeping the thickness of the portion the same.

  Moreover, it is desirable that the area ratio between the ventilation portion and the sealing portion is appropriately controlled so that the workpiece can be reliably adsorbed. The area ratio of the ventilation part to the sealing part (venting part / sealing part) is preferably 0.1 or more, more preferably 0.5 or more, still more preferably 1 or more, preferably 20 or less, more preferably 15 or less, more preferably 10 or less. By adjusting the area ratio of the ventilation part and the sealing part within the above range, the work can be easily adsorbed in the use of the suction plate. It becomes easy to maintain.

In 100% by mass of the planar structure, the total amount of the fiber and the substance derived from the fiber is 50% by mass or more, more preferably 60% by mass or more, still more preferably 70% by mass or more, still more preferably 80% by mass or more, More preferably, it is 90% by mass or more, particularly preferably 95% by mass or more, and there is no particular upper limit, but it is preferably 100% by mass and may be 98% by mass or less. If the total amount of fibers and fiber-derived substances is below the above range, the planar structure is not sufficiently flexible, and when the flexible workpiece such as a thin film or glass is adsorbed, the workpiece comes into contact with the ventilation portion. This is not preferable because it may be damaged.
In this specification, the “fiber-derived substance” is a substance in which fibers are physically changed, and the fiber-derived substance includes, for example, a low-melting fiber after heat melting.

<Method for producing planar structure>
The method for producing a planar structure according to the present invention includes a non-woven fabric for middle material (a1) having a low melting point fiber and having a cutout portion, and a non-woven fabric for middle material having a low melting point fiber and having no cutout portion. (A2) is laminated to produce a nonwoven fabric laminate (a), and at least one surface of the nonwoven fabric laminate (a) is brought into contact with a heated mold, and the surface in the thickness direction A step of compressing into a shape.
The portion where the cutout portion of the non-woven fabric for middle material (a1) is present has a ventilation portion in the planar structure because the number of laminated nonwoven fabrics is small. On the other hand, in the non-woven fabric for middle material (a1), the portion where the cut-out portion does not exist has a large number of laminated nonwoven fabrics, and therefore forms a sealing portion in the planar structure. Conventionally, the ventilation portion and the sealing portion are separately formed by dividing the place to be hot-pressed. However, according to the present invention, a planar structure can be produced by a very simple method of laminating a nonwoven fabric having a cutout and a nonwoven fabric not having a cutout and hot pressing them. This is excellent in that the suction plate for the vacuum suction method can be easily manufactured. In this specification, “full surface hot press” refers to compressing the entire surface in a state where at least one side of the nonwoven fabric laminate is in contact with a heated mold, and “hot press” It simply refers to heat compression.

  In FIG. 2, the reference figure which showed typically the manufacturing method of the planar structure which concerns on this invention is shown. The non-woven fabric laminate 4 has a laminated structure of a non-woven fabric 5 for medium material having low melting point fibers and having a cut-out portion 8, and a non-woven fabric for medium material 6 having low melting point fibers and having no cut-out portion. And a non-woven fabric for surface material 7. And this nonwoven fabric laminated body 4 is adhere | attached and integrated | bonded firmly also between each layer firmly while a fiber is firmly adhere | attached by planar (especially whole surface) hot press.

1. Production of non-woven fabric for intermediate material Hereinafter, a method for producing the non-woven fabric for intermediate material (a1) having a cut-out portion and the non-woven fabric for intermediate material (a2) having no cut-out portion will be described in detail. The intermediate material nonwoven fabric (a1) and the intermediate material nonwoven fabric (a2) may have the same configuration or different configurations, and examples of the fibers include the intermediate material nonwoven fabric (a) and the intermediate material nonwoven fabric ( It may be included in at least one or both of a2).

  Since the planar structure is integrated by hot pressing, the non-woven fabric for medium material needs to contain low melting point fibers. In the present specification, the low melting point fiber means a melting point of preferably 80 ° C. or higher, more preferably 85 ° C. or higher, still more preferably 90 ° C. or higher, preferably 220 ° C. or lower, more preferably 210 ° C. or lower, still more preferably. A fiber of 200 ° C. or lower. The melting point of the low-melting fiber can be appropriately selected according to the use environment, but can be used without deformation or expansion even in a high-temperature environment within the above range.

The low melting point fiber is not particularly limited as long as it is usually used in the manufacture of nonwoven fabrics. A composite fiber having a core-sheath structure, an eccentric structure, or a side-by-side structure in which a plurality of resins having different melting points are combined; modified polyester fiber; Fibers: Modified polyolefin fibers such as modified polypropylene fibers can be used. When a plurality of resins having different melting points are combined, the melting point of the fiber having the lowest melting point represents the melting point of the low melting point fiber. Examples of the combination of resins used for the composite fiber include polyolefin-based combinations such as polyethylene-polypropylene and polypropylene-modified polypropylene, polyethylene-polyester, polyester-modified polyester, and nylon-modified nylon. Depending on the melting point, low melting point fibers made of a single resin can also be used. As the low melting point fiber, it is preferable to use a fiber having an optimum melting point in consideration of a molding temperature and the like.
Among these, a composite fiber having a core-sheath structure is preferable because of its high productivity and easy availability. Examples of the core component include polyester resins such as polyethylene terephthalate and polybutylene terephthalate; polyamide resins such as nylon 6 and nylon 66; among them, polyester resins are preferable, and polyethylene terephthalate is particularly preferable. The sheath component is preferably a modified polyester or copolymer polyester as the low melting point component. Examples of the copolymer component of polyethylene terephthalate include isophthalic acid, adipic acid, diethylene glycol, and hexanediol. In particular, a composite fiber having a core-sheath structure of polyester resin / modified polyester is preferable because it has many finenesses and melting points and is easy to handle at the time of nonwoven fabric production or press working.

  When a hard fiber is used as the low-melting fiber, the rigidity of the planar structure can be secured. Therefore, the glass transition temperature of the low-melting point portion of the low-melting fiber is preferably 10 ° C or higher, more preferably 20 ° C or higher, and still more preferably. It is 30 ° C. or higher, preferably 90 ° C. or lower, more preferably 80 ° C. or lower, and further preferably 70 ° C. or lower.

  The fiber length of the low-melting fiber is preferably 300 mm or less, more preferably 200 mm or less, still more preferably 100 mm or less, preferably 10 mm or more, more preferably 15 mm or more, still more preferably 20 mm or more, because short fibers are preferable. It is. By adjusting the fiber length of the low melting point fiber within the above range, the fibers can be easily entangled, and the number of intersections with the fibers increases, so that an appropriate strength can be imparted to the planar structure.

  The fineness of the low melting point fiber is preferably 1 dtex or more, more preferably 1.5 dtex or more, further preferably 2 dtex or more, preferably 40 dtex or less, more preferably 30 dtex or less, and further preferably 25 dtex or less. By adjusting the fineness of the low melting point fiber within the above range, it is possible to impart rigidity to the planar structure and prevent deformation.

  The non-woven fabric for intermediate material may contain the same type of low-melting fiber, or may contain two or more different types of low-melting fiber, but it has fineness from the viewpoint of ease of melting by heat and imparting rigidity. It is desirable to include two or more different low melting point fibers.

The first low-melting fiber is preferably thin so as to be easily melted, preferably 1 dtex or more, more preferably 2 dtex or more, further preferably 3 dtex or more, preferably 10 dtex or less, more preferably 7 dtex or less. More preferably, it is 6 dtex or less.
The second low-melting fiber is preferably thicker than the first low-melting fiber in order to give rigidity to the planar structure, preferably more than 10 dtex, more preferably 15 dtex or more, and still more preferably 18 dtex. It is above, and is 40 dtex or less, More preferably, it is 30 dtex or less, More preferably, it is 25 dtex or less.

The first low melting point fiber preferably has a low melting point so that it can be easily melted. The melting point of the first low melting point fiber is preferably 80 ° C. or higher, more preferably 85 ° C. or higher, still more preferably 90 ° C. or higher. Preferably, it is 160 ° C. or lower, more preferably 150 ° C. or lower, and further preferably 145 ° C. or lower.
The melting point of the second low melting point fiber is preferably more than 160 ° C., more preferably 170 ° C. or more, further preferably 180 ° C. or more, preferably 220 ° C. or less, more preferably 210 ° C. or less, still more preferably 200 ° C. It is as follows.

  The mass ratio of the first low-melting fiber and the second low-melting fiber (first low-melting fiber / second low-melting fiber) is preferably 0.05 or more, more preferably 0.10 or more, and still more preferably Is 0.15 or more, preferably 0.40 or less, more preferably 0.35 or less, and still more preferably 0.30 or less. By adjusting the mass ratio within the above range, ease of melting and imparting rigidity can be exhibited in a balanced manner.

In 100% by mass of the non-woven fabric for intermediate material, the total mass of the low melting point fibers is preferably 30% by mass or more, more preferably 50% by mass or more, still more preferably 60% by mass or more, and preferably 100% by mass or less. Preferably it is 95 mass% or less, More preferably, it is 90 mass% or less. By adjusting the total mass of the low melting point fiber within the above range, the adhesiveness in the sealing part becomes good, and the occurrence of problems such as air leaks is suppressed when used as an adsorption plate, and the degree of vacuum is lowered. Can also be prevented.
In addition, in the non-woven fabric for middle material (a1) having a cut-out portion, which will be described later, the sealing portion is further melted to fill the gap so that the difference in thickness between the ventilation portion and the sealing portion is reduced when hot pressing is performed. Therefore, the total mass of the low melting point fibers is preferably 70% by mass or more, more preferably 75% by mass or more, and further preferably 80% by mass or more, in 100% by mass of the non-woven fabric for middle material. It is desirable.

  The non-woven fabric for medium material may contain fibers other than the low melting point fiber as appropriate. Examples of the fibers that are preferably combined include non-heat-bondable fibers that do not heat-bond the intersections of the fibers. Examples of the non-heat-bondable fiber include natural fibers such as cotton, hemp, hair, and silk; regenerated fibers such as rayon, polynosic, cupra, and reyocell; semisynthetic fibers such as acetate fiber and triacetate fiber; nylon 6, Polyamide fibers such as nylon 66; Polyester fibers such as polyethylene terephthalate fibers, polybutylene terephthalate fibers, polylactic acid fibers, and polyarylate fibers; Acrylic fibers such as polyacrylonitrile fibers and polyacrylonitrile-vinyl chloride copolymer fibers; Polyethylene fibers, polypropylene Polyolefin fibers such as fibers; polyvinyl alcohol fibers such as vinylon fibers and polyvinyl alcohol fibers; polyvinyl chloride fibers such as polyvinyl chloride fibers, vinylidene fibers and polyclar fibers; synthetic fibers such as polyurethane fibers; Emissions oxide fibers, polyether fibers such as polypropylene oxide fibers can be exemplified. Especially, since moderate rigidity can be provided to a nonwoven fabric, it is desirable that the polyester fiber (more preferably, a polyethylene terephthalate fiber) is contained.

  Non-heat-bondable fibers also include crimped fibers that have mechanical crimps (eg, fine peaks like a sawtooth) or three-dimensional crimps (eg, coiled). Due to the spring effect of the crimped fibers, the space in the planar structure can be maintained, and an appropriate cushioning property can be imparted to the planar structure. Therefore, moderate ventilation is exhibited in the ventilation part, and sag and deformation due to long-term use can be suppressed. In addition, since the planar structure can be finished flexibly, damage to the workpiece can be suppressed in the vacuum suction method. As the crimped fiber, either an actual crimped fiber or a latent crimped fiber can be used.

  As the crimped fiber, a core-sheath fiber having an eccentric structure made of a resin having a different heat shrinkage rate as exemplified by a combination of polyethylene-polypropylene, polyethylene-polyester, polyester-modified polyester, or a composite fiber having a side-by-side structure; Examples thereof include crimped fibers in which the degree of heat treatment is varied between the front side and the back side of the fibers to express three-dimensional crimps; fibers in which the fibers are crimped by an external force;

  The number of crimps of the crimped fibers contained in the planar structure is preferably 3/25 mm or more, more preferably 5/25 mm or more, still more preferably 7/25 mm or more, preferably 25/25 mm. Hereinafter, it is more preferably 20 pieces / 25 mm or less, and further preferably 15 pieces / 25 mm or less. By adjusting the number of crimps within the above range, the balance between the deformation due to long-term use and the air flow rate can be improved.

  The non-heat-fusible fiber may contain a fiber having a static electricity suppressing effect. Examples of the static electricity suppressing fiber include a fiber in which a metal such as copper that is difficult to be charged is present in the fiber. Specifically, a metal such as copper is coated on the surface of a polyester fiber, an acrylic fiber, a polyamide fiber, or the like. And the like. If the antistatic fiber is mixed with the non-woven fabric for the intermediate material, it becomes possible to omit the post-process such as antistatic.

  The cross-sectional shape of the non-heat-bondable fiber is not particularly limited, and any of round cross-sections; irregular cross-sections such as triangles, stars, and pentagons can be used. As the non-heat-bondable fiber, either a solid fiber or a hollow fiber can be used.

  The low-melting fiber and the non-heat-bondable fiber used as necessary are preferably fibers (particularly chemical fibers) composed of a common resin. The common resin includes one resin and its modified resin. For example, when one resin is a polyester resin, the range of the common resin includes a polyester resin and a modified polyester resin. The use of a common resin is preferable because the compatibility between the resins is good and the adhesion is improved, so that the amount of ventilation is reduced in the sealing portion and the wear resistance is improved in the ventilation portion.

  The fineness of the non-heat-bondable fiber is preferably 4 dtex or more, more preferably 5 dtex or more, still more preferably 6 dtex or more, preferably 40 dtex or less, more preferably 30 dtex or less, and even more preferably 20 dtex or less. By adjusting the fineness of the non-heat-fusible fiber within the above range, it is possible to impart appropriate rigidity to the planar structure.

  The non-heat-bondable fiber is preferably a short fiber, and the fiber length is preferably 10 mm or more, more preferably 20 mm or more, still more preferably 30 mm or more, preferably 300 mm or less, more preferably 100 mm or less, still more preferably. 80 mm or less. By adjusting the fiber length of the non-heat-bondable fiber within the above range, the fibers can be easily entangled, and the number of intersections with the fibers increases, so that an appropriate strength can be imparted to the planar structure.

  The melting point of the non-heat-bondable fiber is not particularly limited, but is preferably higher than that of the low-melting fiber, specifically preferably higher than 220 ° C, more preferably 230 ° C or higher, still more preferably 240 ° C or higher, and still more preferably. Is 250 ° C. or higher, preferably 400 ° C. or lower, more preferably 350 ° C. or lower, still more preferably 330 ° C. or lower. By adjusting the melting point of the non-heat-bondable fiber within the above range, the non-heat-bondable fiber is prevented from melting during hot pressing, and the non-heat-bondable fiber is used as a skeleton of the planar structure. It becomes possible.

In 100% by mass of the non-woven fabric for intermediate material, the total mass of the non-heat-bondable fibers is preferably 0% by mass or more, more preferably 5% by mass or more, still more preferably 10% by mass or more, and preferably 70% by mass. Hereinafter, it is more preferably 50% by mass or less, and still more preferably 40% by mass or less. By adjusting the total mass of the non-heat-bondable fibers within the above range, it is possible to impart an appropriate strength to the planar structure.
In particular, from the viewpoint of imparting appropriate cushioning properties to the ventilation portion, the nonwoven fabric for medium material preferably includes crimped fibers, and the mass of the crimped fiber is preferably 5 mass% or more in 100% by mass of the nonwoven fabric for medium material. More preferably, it is 8 mass% or more, More preferably, it is 10 mass% or more, Preferably it is 40 mass% or less, More preferably, it is 30 mass% or less, More preferably, it is 20 mass% or less.
The mass ratio of the non-heat fusible fiber and the low melting point fiber (non-heat fusible fiber / low melting point fiber) is preferably 0.05 or more, more preferably 0.10 or more, and further preferably 0.12 or more. Yes, preferably 0.35 or less, more preferably 0.30 or less, and still more preferably 0.25 or less. By adjusting the mass ratio within the above range, both the effect of the low-melting fiber and the effect of the non-heat-bondable fiber can be achieved.

Basis weight for medium material nonwoven fabric is preferably 30 g / m ² or more, more preferably 40 g / m ² or more, more preferably 50 g / m ² or more, preferably 200 g / m ² or less, more preferably 150 g / m ² or less, more preferably 80 g / m ² or less. By adjusting the basis weight within the above range, the durability of the planar structure can be increased.

The average fineness of the fibers contained in the non-woven fabric for intermediate material is preferably 2.2 dtex or more, more preferably 3.5 dtex or more, still more preferably 4.0 dtex or more, preferably 22 dtex or less, more preferably 21 dtex or less, further Preferably it is 20 dtex or less. By adjusting the average fineness within the above range, the size of the gap between the fibers can be controlled. As a result, it is possible to suppress a decrease in the adsorption force due to foreign matters such as dust and oil being taken in between the fibers, while preventing a decrease in the air flow rate due to the voids becoming too small.
In the present specification, the “average fineness” is obtained by a weighted average considering the ratio (weight basis) of fibers of each fineness when a plurality of fibers having different finenesses are included.

  The non-woven fabric for intermediate material may be a short-fiber nonwoven fabric or a long-fiber nonwoven fabric, but a short-fiber nonwoven fabric is preferable because it is easy to procure fibers.

The method for producing the intermediate material nonwoven fabric is not particularly limited, and a dry method, a wet method, or the like can be appropriately employed as long as it is a short fiber nonwoven fabric, and a spunbond method can be employed as appropriate when it is a long fiber nonwoven fabric.
The web bonding method is not particularly limited, and a mechanical entanglement method such as a needle punch method, a spun lace method (water entanglement method); a part or all of the low melting point fiber contained in the nonwoven fabric is thermally melted, Various bonding methods such as a method of fixing fiber intersection points (thermal bonding method); The mechanical entanglement method is arbitrary, but in the present invention, in order to strongly entangle the fiber web, it is preferable to use a needle punch and a thermal bond method in which heat treatment is performed after the fibers are entangled by the needle punch method.

In the needle punch method, the conditions of needle punch needle count 36 to 42, needle depth 4 to 10 mm (preferably 5 to 8 mm), and number of driven 10 to 50 / cm ² (preferably 15 to 30 / cm ² ) Is preferred. By adjusting the processing conditions within the above range, the fibers can be easily entangled, so that the durability of the planar structure can be improved and the planar structure can be finished so as not to become too hard.

The heat treatment temperature in the thermal bond method is higher than the glass transition temperature of the low melting point fiber, specifically, preferably 175 to 225 ° C, more preferably 190 to 220 ° C. The heat treatment temperature is preferably T _L +10 (° C.) to T _L +110 (° C.), more preferably T _L +35 (° C.) to T _L +90 (relative to the melting point T _L of the mixed low-melting fiber. ° C). If the heat treatment temperature is within the above range, the low melting point fiber can be melted appropriately. The heating time may be appropriately set in consideration of the melting point and the content of the low-melting fiber to be mixed, but is preferably 15 to 180 seconds, more preferably 20 to 90 seconds. The thermal bond method can be performed using, for example, a heat treatment machine (for example, a circulating hot air dryer) adjusted to a desired temperature.

  After the thermal bonding process, the obtained nonwoven fabric may be smoothed. By performing the smoothing treatment, the nonwoven fabric can be made high in density, the fibers can be prevented from falling off from the nonwoven fabric, and the adhesion between the layers can be strengthened during hot pressing. The smoothing treatment can be performed on one surface or both surfaces of the nonwoven fabric after the thermal bond processing.

  The smoothing treatment can be performed, for example, by passing a thermal bonded nonwoven fabric between a heating roll and a heating plate. Although the heating temperature of a heating roll and a metal plate will not be specifically limited if it is temperature higher than the melting start temperature of a low melting point fiber, 70-220 degreeC is preferable, More preferably, it is 100-210 degreeC. By using a heating roll or a heating plate, the surface of the nonwoven fabric can be melted and smoothed.

2. Cutting process In the cutting process, a non-woven fabric for middle material (a1) having a cut-out portion is manufactured.

  The shape of the cut-out portion can be appropriately selected from a circle, a triangle, a quadrangle, a pentagon or more polygon, a donut shape, and the like as shown in FIG. When a plurality of cutout portions are formed on one non-woven fabric for middle material (a1), the shape of the cutout portions may be the same or different, and may be appropriately selected depending on the application.

  It is desirable that the cutting process is performed inside the non-woven fabric for intermediate material, and the outer peripheral portion of the non-woven fabric is not cut out. This is because if the outer peripheral portion is cut out, air is likely to leak from the side portion of the planar structure when adsorbing the workpiece, and sufficient lift force may not be exhibited.

  By devising the shape and position of the cutout portion, the shape of the ventilation portion can be finely adjusted. For example, when it is desired to form two or more parts with a low air flow rate and parts with a high air flow rate in one ventilation part, the non-woven fabric for intermediate material (a1) cut out in the shape of the ventilation part and finishing with a low ventilation quantity What is necessary is just to produce the nonwoven fabric for intermediate materials (a1) which cut out the part which wants, and to laminate | stack these. Similarly, in the case of multi-point adsorption, it is possible to adjust the air flow rate by adjusting the shape and position of the cutout portion.

  The cutout part is formed by cutting out an unnecessary nonwoven fabric by a punching machine, a cutter, laser processing or the like.

3. Lamination 3-1. In this step, the nonwoven fabric for middle material (a1) having a cutout portion and the nonwoven fabric for intermediate material (a2) having no cutout portion are laminated to form a nonwoven fabric laminate ( a) is prepared. FIG. 2 shows a reference diagram schematically showing a method for producing a planar structure. As shown in FIG. 2, the nonwoven fabric laminate (a) is a non-woven fabric for middle materials (a1) having a cutout portion. It is preferable to have a laminated structure including the intermediate nonwoven fabric (a2) that does not have a cut-out portion, and a surface nonwoven fabric (b) that is optionally laminated outside the laminated structure.

  The number of laminated non-woven fabrics (a1) having a cutout portion is preferably 3 or more, more preferably 8 or more, and even more preferably 10 or more, although there is some increase or decrease depending on the thickness or basis weight. Is 50 sheets or less, more preferably 40 sheets or less, and still more preferably 35 sheets or less. By adjusting the number of laminated layers of the intermediate material non-woven fabric (a1) within the above range, it becomes easy to control the air flow rate of the ventilation portion and the sealing portion within a predetermined range. When two or more intermediate nonwoven fabrics (a1) having cutout portions are laminated, these nonwoven fabrics may be the same or different.

  The number of laminated non-woven fabrics for intermediate materials (a2) that do not have a cut-out portion is preferably 1 or more, more preferably 2 or more, and even more preferably 3 or more, although there is some increase or decrease depending on the thickness or basis weight. The number is preferably 30 sheets or less, more preferably 25 sheets or less, and still more preferably 20 sheets or less. By adjusting the number of laminated layers of the intermediate material non-woven fabric (a2) within the above range, it becomes easy to control the air flow rate of the ventilation portion and the sealing portion within a predetermined range. When two or more intermediate nonwoven fabrics (a2) having no cutout portions are laminated, these nonwoven fabrics may be the same or different.

  The ratio of the number of laminated layers of the non-woven fabric for intermediate material (a1) having a cut-out portion to the non-woven fabric for intermediate material (a2) having no cut-out portion (the non-woven fabric for intermediate material (a1) / non-woven fabric for intermediate material (a2)) is preferably Is 1.0 or more, more preferably 1.5 or more, still more preferably 1.8 or more, preferably 4.0 or less, more preferably 3.5 or less, and still more preferably 3.1 or less. By adjusting the ratio of the number of stacked layers within the above range, it becomes easy to control the amount of air flow within a predetermined range while reducing the difference in thickness between the air-permeable portion and the sealing portion.

The lamination method of the non-woven fabric for intermediate material (a1) having a cut-out portion and the non-woven fabric for intermediate material (a2) having no cut-out portion is as follows.
(1) A cutout structure portion composed of 1 to 5 pieces of the non-woven fabric for middle material (a1) having the cutout portion, and the cutout portion so that any number of laminated non-woven fabrics for intermediate materials does not deviate Producing a non-cutout structure part composed of 1 to 5 non-woven fabrics for intermediate materials (a2), and alternately laminating three or more cutout structure parts and non-cutout structure parts;
(2) One cutout structure part made of only the nonwoven fabric for middle material (a1) having the cutout part and one non-cutout structure part made of only the nonwoven fabric for intermediate material (a2) not having the cutout part And a method of stacking the cutout structure portion and the non-cutout structure portion so that they are adjacent to each other;
Etc. As the lamination method, (1) is preferable so that wrinkles and the like are not generated in the planar structure during hot pressing.

  When anti-static fibers are included in the non-woven fabric for intermediate materials, sufficient anti-static effects are exhibited even if the number of laminated non-woven fabrics for intermediate materials containing anti-static fibers is small. It is also possible to suppress price increases. The number of laminated nonwoven fabrics for intermediate materials containing static electricity suppressing fibers is preferably 3 or less, more preferably 2 or less, and even more preferably 1. Moreover, since it is preferable that the nonwoven fabric for intermediate materials containing static electricity suppression fiber is laminated on the front side of the nonwoven fabric laminate (a) because the static electricity suppressing effect is easily exhibited, the nonwoven fabric is from the front side of the nonwoven fabric laminate (a). It is desirable to laminate at the position of the 1st to 5th sheets (preferably the 1st to 3rd sheet, more preferably the 1st to 2nd sheet, and still more preferably the 1st sheet).

  The non-woven fabric laminate (a) before hot pressing contains the non-woven fabrics for middle materials (a1) to (a2) as long as they include the non-woven fabrics for middle materials (a1) to (a2) and the planar structure can be produced by hot pressing. Layers other than a2) may be included. The layers other than the non-woven fabric for middle material (a1) to (a2) may be layers containing low-melting fibers or layers not containing low-melting fibers.

3-2. Method for Laminating Nonwoven Fabric for Surface Material The nonwoven fabric laminate (a) can also include a nonwoven fabric for surface material as a layer other than the non-woven fabric for middle material (a1) to (a2). The nonwoven fabric for surface material is a layer laminated in order to make the surface of the planar structure more smooth, and the nonwoven fabric is preferably laminated at least as the outermost layer of the nonwoven fabric laminate (a).

  In order to smooth the surface of the planar structure, the surface nonwoven fabric desirably contains low melting point fibers. As the low melting point fiber, those exemplified above can be appropriately used. The non-woven fabric for the surface material may contain the same type of low-melting fiber, or may contain two or more different types of low-melting fibers. However, from the viewpoint of ease of melting by heat, the fineness is low. It is desirable to include two or more melting point fibers.

As the surface nonwoven fabric, it is preferable to use a thin fiber that is easy to melt as the third low-melting fiber, and the fineness of the fiber is preferably 1 dtex or more, more preferably 2 dtex or more, and further preferably 3 dtex or more. Yes, preferably 10 dtex or less, more preferably 7 dtex or less, still more preferably 6 dtex or less.
Further, as the fourth low melting point fiber, in order to increase the amount of resin, it is preferable to use a fiber having a larger diameter than the third low melting point fiber, and the fineness of the fiber is preferably more than 10 dtex, more preferably 15 dtex or more, More preferably, it is 18 dtex or more, 40 dtex or less, More preferably, 30 dtex or less, More preferably, it is 25 dtex or less.

The third low melting point fiber and the fourth low melting point fiber may have the same melting point (for example, a difference in melting point of 0 to 15 ° C.) or may be different from each other (for example, the difference in melting point is different). In order to melt as many low melting point fibers as possible during hot pressing and smooth the surface of the planar structure, the melting points of the third low melting point fiber and the fourth low melting point fiber are approximately the same. Preferably, the difference between the melting points of the third low melting point fiber and the fourth low melting point fiber is preferably 10 ° C. or less, more preferably 5 ° C. or less.
Specifically, the melting points of the third low-melting fiber and the fourth low-melting fiber are preferably 80 ° C. or higher, more preferably 85 ° C. or higher, still more preferably 90 ° C. or higher, preferably 160 ° C. or lower, more Preferably it is 150 degrees C or less, More preferably, it is 145 degrees C or less.

  The mass ratio of the third low melting point fiber to the fourth low melting point fiber (third low melting point fiber / fourth low melting point fiber) is preferably 0.5 or more, more preferably 1.2 or more, and still more preferably. Is 2.0 or more, preferably 8.0 or less, more preferably 7.0 or less, and even more preferably 6.0 or less. By adjusting the mass ratio within the above range, it is possible to melt as much of the low melting point fiber as possible.

  The non-woven fabric for the surface material may contain fibers other than the low melting point fibers as appropriate, and examples of the fibers that can be preferably combined include non-heat-bondable fibers. As the non-heat-fusible fiber, those exemplified above can be used as appropriate, but the non-woven fabric for the surface material may contain a static-suppressing fiber in order to enhance the static-suppressing effect of the planar structure. .

  In 100% by mass of the nonwoven fabric for surface material, the total mass of the low melting point fibers is preferably 80% by mass or more, more preferably 90% by mass or more, still more preferably 95% by mass or more, and particularly preferably 100% by mass. However, it may be 98% by mass or less. As the amount of the low-melting fiber increases, the surface of the planar structure becomes smooth when used as a surface material, so that a planar structure having excellent wear resistance can be obtained.

  The average fineness of the fibers contained in the surface nonwoven fabric is preferably 1.3 dtex or more, more preferably 3.0 dtex or more, still more preferably 5.0 dtex or more, in order to facilitate smoothing the surface of the planar structure. More preferably, it is 6.0 dtex or more, Preferably it is 12 dtex or less, More preferably, it is 11 dtex or less, More preferably, it is 10 dtex or less.

Basis weight of the surface material for the nonwoven fabric is preferably 5 g / m ² or more, more preferably 10 g / m ² or more, more preferably 15 g / m ² or more, preferably 100 g / m ² or less, more preferably 60 g / m ² or less, more preferably 40 g / m ² or less, and still more preferably 35 g / m ² or less. It is preferable to adjust the basis weight within the above range since the function of the fibers contained in the nonwoven fabric for the surface material is sufficiently exhibited.

  The method for producing the non-woven fabric for the surface material may refer to the method for producing the non-woven fabric for the mid-material, but the non-woven fabric for the surface material is preferably a short fiber non-woven fabric, and the non-woven fabric is not entangled with the fibers by the needle punch method. It is desirable to manufacture by the thermal bond method which performs heat processing. Moreover, it is desirable that any one surface or both surfaces of the nonwoven fabric for surface material is subjected to a smoothing treatment.

  The surface nonwoven fabric may or may not have a cut-out portion, but if the surface of the planar structure is made smoother, the workpiece can be stabilized when used as an adsorption plate. Since it can adsorb | suck, it is desirable that the cutout part does not exist in the nonwoven fabric for surface materials.

In the nonwoven fabric laminate, the surface nonwoven fabric is preferably laminated at least on the adsorption surface, and desirably laminated on both surfaces of the nonwoven fabric laminate. The number of laminated nonwoven fabrics for the surface material may be one or two or more, but preferably two. In addition, when laminating | stacking two or more surface material nonwoven fabrics, the surface material nonwoven fabrics may be respectively the same or different.
The intermediate material nonwoven fabric and the surface material nonwoven fabric may be subjected to a post-process as necessary. Examples of the post-process include functional processing such as coloring treatment, antistatic treatment, water repellent treatment, and antifouling treatment. In the process of imparting functionality, a binder resin containing functional agents such as a colorant, an antistatic agent, a water repellent, and an antifouling agent is impregnated, sprayed, and applied to the nonwoven fabric laminate after hot pressing (note that the coating solution) Includes a foamed binder resin).

4). Planar (or entire surface) hot press Low melting point mixed with the nonwoven fabric by compressing at least one surface of the nonwoven fabric laminate (a) obtained in the above-mentioned step in contact with a heated mold. The fibers are fused, the fibers are firmly bonded together, and the layers are also firmly bonded, so that there is almost no difference in thickness between the ventilation portion and the sealing portion. The fusion refers to a state in which the low-melting fiber is once melted at least on the surface to be integrated with other fibers, at least a part of the shape of the low-melting fiber is broken, and a plurality of fibers are melted. This is a state different from the original state in that it is bonded via the solidified low melting point fiber.

  The mold used for the hot press can be freely selected such as a plate shape, a bowl shape, and an uneven shape having peaks and valleys. In order to smooth the surface of the planar structure, the surface of the mold is preferably flat.

The treatment temperature during hot pressing is preferably 90 ° C. or higher, more preferably 100 ° C. or higher, more preferably 105 ° C. or higher, preferably 230 ° C. or lower, more preferably 220 ° C. or lower, still more preferably 210 ° C. or lower. is there. It is preferable to adjust the treatment temperature within the above range because the adhesive strength between the nonwoven fabrics is improved. On the other hand, when the treatment temperature is lower than the above range, the surface of the planar structure cannot be sufficiently smoothed, and further, there is a possibility that appropriate hardness cannot be imparted to the ventilation part or the sealing part, which is not preferable.
For the same reason, the treatment time during hot pressing is preferably 100 seconds or more, more preferably 150 seconds or more, still more preferably 200 seconds or more, preferably 1000 seconds or less, more preferably 800 seconds or less, and still more preferably. Is 700 seconds or less.

  At the time of hot pressing, it is preferable that at least one surface or both surfaces of the nonwoven fabric laminate (a) obtained in the above step are in contact with a heated mold. Also, during heat pressing, if the heat source is on the side that becomes the adsorption surface of the planar structure, the adsorption surface of the planar structure can be heat-treated at a higher temperature, which reduces the irregularities on the surface of the planar structure. As a result, the surface of the planar structure is smoothed and deformation of the workpiece can be suppressed. Further, since the abrasion resistance of the planar structure is improved, the fiber can be prevented from fuzzing or coming off, and this is effective because it can suppress problems caused by the fiber dropping even when used as a filter.

  You may implement a post process to the nonwoven fabric laminated body after a hot press. As a post-process, the process similar to the post-process demonstrated with the nonwoven fabric for middle materials, and the nonwoven fabric for surface materials can be implemented.

  In the case where the effect of the fiber oil agent adhering to the raw material fibers causing slipping of the workpiece occurs, the fiber, the nonwoven fabric, or the nonwoven fabric laminate is washed before and after manufacturing the nonwoven fabric and / or before and after the heat press in order to remove the fiber oil agent. Good.

<Application>
The planar structure according to the present invention can be used as a suction plate for a vacuum suction device or a filter.

FIG. 3 shows one mode when a planar structure is used as a suction plate. The vacuum suction device 14 includes a base body 11, a vacuum port 12 connected to a flow path formed in the base body 11, and a suction portion 13 existing at the other end of the vacuum port 12 through the flow path. The suction plate (planar structure) 1 is placed on the side where the suction part 13 is present. At this time, it is desirable that the suction plate 13 be placed in contact with the ventilation part 2 and the suction part 13 of the suction plate 1. . When such a suction plate 1 is used, the workpiece 10 can be fixed by the suction force by the suction unit 13.
An elastic member (foamed material such as sponge, non-woven fabric, etc.) may be installed between the suction plate 1 and the base body 11. When an elastic member is installed, it is possible to prevent a gap from being formed between the base body 11 and the suction plate 1 and to buffer an impact when the work 10 is sucked, thereby improving the quality of vacuum suction.
The size of the suction plate can be adjusted as appropriate according to the use environment, but the area is ² to 1500 cm ² , and the shape is usually a circle / square (rectangle / square). Further, since the planar structure is lightweight, it is suitable for vacuum suction of a large workpiece with a small load on driving. Furthermore, since the planar structure is flexible, it is suitable for transferring a flexible work such as a thin film or glass.

  In addition, when the planar structure is used as a filter, a liquid processing filter, an air filter for an air conditioner such as a building or a factory, an air filter for an air conditioner / air purifier, or the like is preferable. This is because, according to the planar structure according to the present invention, it is not necessary to attach an aluminum frame or the like, and installation, replacement, and disposal are facilitated.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited by the following examples, but may be appropriately modified within a range that can meet the purpose described above and below. Of course, it is possible to implement them, and they are all included in the technical scope of the present invention.

<Evaluation method>
The planar structure was evaluated based on the following method.
(1) Basis weight; conforms to JIS L1913 6.2.
(2) Thickness: Conforms to JIS L1913 6.1B.
(3) Density: The basis weight is divided by the thickness, and the unit is converted to g / cm ³ .
(4) Aeration rate: Conforms to JIS L1913 6.8.1.
(5) Hardness (HDD): Measured according to JIS K7215 (Durometer type D). When the thickness is 6 mm or less, the planar structures are stacked and measured.
(6) Surface smoothness: The surface of the planar structure is visually and tactilely observed for unevenness and evaluated based on the following criteria.
A: There is no unevenness and it is very smooth.
○: Smooth without any irregularities.
(Triangle | delta): There is no convexity and it is smooth, but there is a concave.

<Manufacture of non-woven fabric>
Nonwoven fabric A was produced by winding a fiber web obtained by blending the fibers shown in the following table and spinning from a card machine through a hot roll at 115 ° C.
Nonwoven fabric B is a fiber web obtained by blending the fibers shown in the following table and spun from a card machine. The web is driven from one side by a needle punch machine and entangled at a number of 20 / cm ² and a needle depth of 6 mm, and then kept at 200 ° C. It was manufactured by treating with a hot air treatment machine for 30 seconds and then passing it through a 200 ° C. hot roll.
The nonwoven fabric C was produced in the same manner as the nonwoven fabric B except that the number of punches was 60 / cm ² , the needle depth was 9 mm, and needle punching was performed from both sides.
The nonwoven fabric D was produced in the same manner as the nonwoven fabric B except that the fibers to be blended were changed as shown in the table below, and needle punching was performed from one side at a driving number of 60 / cm ² and a needle depth of 9 mm.
In the table, “LPET” is a low melting point fiber (core: PET, sheath: modified polyester) having a core-sheath structure, and “PET” is a polyester fiber having a solid and mechanical crimp (9/25 mm). is there.

Example 1
14 non-woven fabrics having a cutout portion (a1), 14 non-woven fabrics in which the inside of the non-woven fabric B is cut into a circle having a diameter of 12 mm with a punching machine (one circle is formed per 2 cm × 2 cm) As the non-woven fabric for intermediate materials (a2), five non-woven fabrics that did not cut out the inside of the non-woven fabric B were prepared. After the non-woven fabrics for intermediate materials (a1) and (a2) were laminated relatively uniformly so that the number of laminated sheets would not be biased, one nonwoven fabric A was laminated on each side of the obtained laminate.
The nonwoven fabric laminate in which 21 nonwoven fabrics were laminated was pressed for 600 seconds with a hot press machine having a heating plate temperature of 120 ° C. with both surfaces of the nonwoven fabric laminate contacting the heating plate. After cooling, the periphery was cut to produce a 6 cm × 10 cm planar structure.

Examples 2-3
In Example 2, a non-woven fabric obtained by cutting the inside of the non-woven fabric B into a 12 mm × 12 mm square with a punching machine (one square was formed per 2 cm × 2 cm) was used as the intermediate material non-woven fabric (a1) having cutout portions. did.
In Example 3, the non-woven fabric obtained by cutting the inside of the non-woven fabric B into a square of 50 mm × 110 mm with a punching machine was used as the intermediate material non-woven fabric (a1) having a cut-out portion.
A planar structure was produced in the same manner as in Example 1 except for the above.

Comparative Examples 1-5
In Comparative Example 1, a non-woven fabric C and a non-woven fabric D are laminated one by one, and then the outer peripheral portion of the non-woven fabric laminate is hot-pressed over the entire circumference with a width of 15 mm under the conditions shown in the table. did.
In the comparative example 2, the planar structure which does not have a ventilation | gas_flowing part was manufactured using only the nonwoven fabric B which does not have a cutout part as a nonwoven fabric for intermediate materials.
In Comparative Example 3, the number of laminated nonwoven fabrics B having no cut-out portions was reduced, and a planar structure having good air permeability (that is, no sealing portion) was produced over the entire surface.
In Comparative Example 4, a PP resin sintered body was used as a commercially available adsorption plate.
In Comparative Example 5, a fluororesin sintered body was used as a commercially available planar structure.

  As shown in the above table, the planar structure according to the present invention uses nonwoven fabric as a raw material, and therefore has a desired hardness due to the presence of melted and solidified low melting point fibers while having appropriate flexibility and air permeability. Have. In addition, since the planar structure is manufactured by hot pressing the entire nonwoven fabric laminate, it is possible to easily adjust the density and air flow rate at low cost by appropriately changing the characteristics of the nonwoven fabric to be laminated. It is also possible to smooth the surface of the planar structure.

From Examples 1 to 3, it can be seen that the air flow rate and thickness of the planar structure can be adjusted by the basis weight, thickness, number, etc. of the laminated nonwoven fabric. Also, the shape of the ventilation portion can be arbitrarily set.
When Examples 1 to 3 and Comparative Example 1 are compared, the method described in Patent Documents 6 to 7 has a large difference in thickness between the ventilation portion and the sealing portion, and in recent years, matches the suction plate. It is difficult to find a vacuum suction device, and air leakage from the side surface of the ventilation portion tends to occur, which is not preferable.
When Example 2 is compared with Comparative Examples 2 and 3, it can be seen that only the sealing portion or only the ventilation portion does not exhibit the desired performance in terms of the amount of ventilation and the hardness.
When Examples 1-3 and Comparative Examples 4-5 are contrasted, the surface smoothness is not sufficient in a commercially available sintered body.

DESCRIPTION OF SYMBOLS 1 Planar structure 2 Ventilation part 3 Sealing part 4 Nonwoven fabric laminated body (a)
5 Non-woven fabric for middle materials having a cut-out part (a1)
6 Non-woven fabric for intermediate materials (a2) without cutout
7 Nonwoven fabric for surface material 8 Cut-out part 10 Work 11 Base body 12 Vacuum port 13 Suction part 14 Vacuum adsorption device

Claims (15)

A planar structure composed of non-woven fabric,
And having in the surface both one or more ventilation portions and one or more sealing portions having a lower air flow rate than the ventilation portions,
The planar structure is characterized in that the HDD of the ventilation section is 13 or more and 45 or less.   The planar structure according to claim 1, wherein the sealing portion has an HDD of 65 to 85 inclusive. The ventilation rate of the ventilation part is 20 cm ³ / cm ² · sec or more and 250 cm ³ / cm ² · sec or less, and the ventilation rate of the sealing part is 0 cm ³ / cm ² · sec or more and 10 cm ³ / cm ² · sec or less. The planar structure according to claim 1 or 2.   The planar structure according to any one of claims 1 to 3, wherein a thickness of the ventilation portion is 0.8 times or more and 1.05 times or less with respect to a thickness of the sealing portion.   The planar structure according to any one of claims 1 to 4, wherein a ratio of a basis weight of the ventilation portion to the sealing portion (ventilation portion / sealing portion) is 0.05 or more and 0.70 or less. Density of vent is not more than 0.15 g / cm ³ or more 0.50 g / cm ^3, of the preceding claims density of the sealing portion is not more than 0.50 g / cm ³ or more 1.50 g / cm ³ The planar structure according to any one of the above.   The planar structure according to any one of claims 1 to 6, wherein a low melting point fiber having a melting point of 80 ° C or higher and 220 ° C or lower is present on the surface of the planar structure in a melted and solidified state.   The suction plate for vacuum suction methods containing the planar structure in any one of Claims 1-7.   The filter containing the planar structure in any one of Claims 1-7. A non-woven fabric laminate (a) by laminating a non-woven fabric for middle materials (a1) having low melting point fibers and having cutout portions and a non-woven fabric for middle materials (a2) having low melting point fibers and not having cutout portions. And the step of producing
A method for producing a planar structure comprising the step of compressing the nonwoven fabric laminate (a) into a planar shape in the thickness direction while bringing at least one surface of the nonwoven fabric laminate (a) into contact with a heated mold.   At least one of the non-woven fabric for intermediate materials (a1) having the cutout portion and the non-woven fabric for intermediate materials (a2) not having the cutout portion includes non-heat-bondable fibers having a melting point higher than that of the low-melting fibers. A method for producing the planar structure according to 10. The basis weight of the non-woven fabric for middle material (a1) having a cut-out portion is 30 g / m ² or more and 200 g / m ² or less, and the number of laminated layers is 3 or more and 50 or less,
The planar structure according to claim 10 or 11, wherein the basis weight of the non-woven fabric for intermediate material (a2) having no cut-out portion is 30 g / m ² or more and 200 g / m ² or less, and the number of laminated layers is 1 or more and 30 or less. Manufacturing method. The non-woven fabric laminate (a) includes a cut-out structure portion composed of 1 to 5 non-woven fabrics for middle materials (a1) having the cut-out portions, and a non-woven fabric for intermediate materials (a2) having no cut-out portions. Having 1 to 5 non-cutout structures,
The manufacturing method of the planar structure in any one of Claims 10-12 by which 3 or more layers of a cutout structure part and a non-cutout structure part are laminated | stacked alternately.   The manufacturing method of the planar structure in any one of Claims 10-13 by which the nonwoven fabric for skin materials is laminated | stacked as outermost layer of a nonwoven fabric laminated body (a).   The method for producing a planar structure according to claim 14, wherein the total mass of the low-melting fibers is 80% by mass or more in 100% by mass of the nonwoven fabric for skin material.