JP2010172967A - Suction-fixing sheet and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a suction-fixing sheet capable of further reliably applying a suction force of a suction unit to suck an article to be carried. <P>SOLUTION: The suction-fixing sheet 100 includes a porous film 10, which has one main surface 11 as a suction surface 11 to be subjected to a suction action by the suction unit and the other main surface 12 as a working surface 12 arranged toward the article to be sucked; wherein, at least in a part of an end portion 15 of the porous film 10, pores in the porous film 10 are filled with resin 30 to suppress air leakage from a side surface 13 of the porous film 10 to the suction surface 11 when the suction surface 11 is subjected to the suction action from the suction unit. Preferably, the porous film 10 comprises a sintered body of ultra-high molecular weight polyethylene (UHMWPE) powder. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a sheet used for suction of an object to be conveyed using a suction unit.

  Adsorption conveyance is one of methods for conveying plate-shaped or sheet-shaped articles such as metal foil, plastic film, glass substrate for display, ceramic green sheet, and semiconductor wafer. The suction conveyance is performed in a state where a suction unit having a vacuuming function is used and the conveyance target article is sucked to the suction unit via a suction fixing sheet attached to the suction unit.

  As a sheet for adsorbing and fixing, a porous film represented by a sheet made of a sintered body of ultra high molecular weight polyethylene (UHMWPE) powder having an average molecular weight of 500,000 or more is known (Patent Document 1). The adsorption of the article by the suction unit is more specifically subjected to the suction action from the suction unit from the main surface (working surface) arranged toward the article, using the holes formed in the porous film. This is performed by sucking air to the opposite main surface (suction surface).

JP 2002-173250 A

  The conventional porous membrane as disclosed in Patent Document 1 is in a state where air escapes from the side surface of the membrane to the suction surface. For this reason, in such a conventional porous membrane, a part of the suction force by the suction unit is not used for the adsorption of the articles and is wasted. In particular, when the porous membrane is thickened to maintain strength, air escape from the side surface of the membrane becomes significant.

  An object of the present invention is to provide a suction fixing sheet that can apply the suction force of the suction unit more reliably for the suction of an article.

  In the present invention, one main surface is a suction surface that receives a suction action from a suction unit, and the other main surface is a work surface disposed toward an article to be adsorbed, and is used for suction fixation. A sheet is filled with a resin in the pores of the porous film at least at a part of the end of the porous film, and when the resin receives a suction action from the suction unit, Provided is an adsorption fixing sheet in which air escape from a side surface to the suction surface is suppressed.

  In another aspect, the present invention provides a method for producing the above-described sheet for adsorbing and fixing, wherein at least a part of the end of the porous membrane is immersed in a filler liquid containing a resin, and the end The method for producing a sheet for adsorbing and fixing, comprising: a step of allowing the filler liquid to penetrate into the pores of the porous membrane; and a step of drying the penetrated filler liquid and filling the pores with the resin. I will provide a.

  In the present invention, the end of the porous membrane is filled with resin. As a result, air is less likely to escape from the side surface of the suction fixing sheet to the suction surface when receiving a suction action from the suction unit, so that the suction force by the suction unit can be more reliably applied for suction fixing of the article.

It is sectional drawing of an example of the sheet | seat for adsorption fixation of this invention. It is sectional drawing of another example of the sheet | seat for adsorption fixation of this invention. It is process drawing for demonstrating the manufacturing method of the sheet | seat shown in FIG. It is a top view of the sheet | seat produced in the Example. It is a figure for demonstrating the use condition of the sheet | seat for adsorption fixation.

  FIG. 1 is a cross-sectional view of an example of the suction-fixing sheet of the present invention, and FIG. 5 is a diagram for explaining a use state of the suction-fixing sheet of the present invention. The adsorption fixing sheet 100 is constituted by a porous film 10. The suction fixing sheet 100 is used by being attached to the suction unit 20 of the transport apparatus shown in FIG. The upper surface 11 of the porous membrane 10 is a suction surface 11 that receives a suction action from the suction unit 20. The lower surface 12 of the porous membrane 10 is a work surface 12 that is located on the side opposite to the suction surface 11 and is arranged toward the article 21 to be adsorbed. The suction unit 20 has a vacuuming function. The conveyed article 21 is adsorbed by the suction unit 20 via the adsorption fixing sheet 100.

  The pores at the end 15 of the porous membrane 10 are filled with the resin 30. Thereby, when receiving a suction action from the suction unit 20, it becomes difficult for air to escape from the side surface 13 to the suction surface 11, and as a result, a reduction in suction force on the work surface is suppressed. On the other hand, the region other than the end 15 of the porous membrane 10 is not filled with resin. In this central region, a suction force is exerted on the work surface 12 with respect to the article 21.

  The effect of suppressing air escape from the side surface 13 to the suction surface 11 can be obtained if the pores of the porous film 10 are filled with the resin 30 in at least a part of the end portion 15. From the viewpoint of sure prevention, it is preferable that the pores are filled with the resin 30 over the entire circumference of the end portion 15 of the porous membrane 10.

  In order to reliably suppress air escape from the side surface 13, the range in which the porous membrane 10 is filled with the resin 30 is indicated by a distance L along the surface from the side surface 13 of the porous membrane 10, and at least It is preferable to be 3 mm. On the other hand, if the distance L is too long, the area of the work surface 12 where the suction force can be obtained is limited. The distance L is preferably 10 mm or less.

  Examples of the material of the porous film 10 include polymer materials such as polyethylene, polypropylene, UHMWPE, fluororesin (for example, polytetrafluoroethylene), polystyrene, polyamide, and polyester. From the viewpoint of achieving both the air permeability and surface smoothness of the membrane, the porous membrane is preferably composed of a sintered body of UHMWPE powder. UHMWPE refers to polyethylene having a viscosity average molecular weight of 500,000 or more. The viscosity average molecular weight of UHMWPE is usually in the range of 2 to 10 million. The viscosity average molecular weight is measured by a method prescribed in ASTM D4020 (viscosity method).

  The sintered body of UHMWPE powder is prepared by, for example, UHMWPE powder (average particle size of 30 to 200 μm) filled in a mold as described in Japanese Patent Publication No. 5-66885 and Japanese Patent Application Laid-Open No. 2006-26981. It is obtained by sintering at a temperature in the vicinity of the melting point. The obtained sintered body is usually block-shaped. If the block-shaped sintered body is formed into a sheet by cutting, the porous film 10 can be obtained. The porous membrane 10 may contain an additive such as a surfactant or a conductive polymer for preventing static charge.

  As the resin that fills the porous membrane 10, a water-soluble resin such as polyvinyl alcohol, polyvinyl pyrrolidone, polyethylene oxide, or sodium polyacrylate is preferable.

  Filling the pores of the porous membrane 10 at the end 15 with the resin 30 can be performed, for example, as follows. A porous film composed of a sintered body of UHMWPE powder and a filler solution obtained by diluting a water-soluble resin typified by polyvinyl alcohol with a lower alcohol such as ethanol or water are prepared. At least a part of the end of the porous membrane is immersed in the filler liquid, and the filler liquid is permeated into the pores of the porous membrane at the end. Thereafter, the infiltrated filler liquid is dried to obtain a state in which the pores are filled with the resin.

  FIG. 2 is a cross-sectional view of another example of the suction fixing sheet of the present invention. In the adsorbing and fixing sheet 101 shown in FIG. 2, the pores of the porous film 10 are filled with the resin 30 with the region 16 in the vicinity of the work surface 12 left at the end 15 of the porous film 10. When the suction fixing sheet 101 receives a suction action from the suction unit 20, an air suction path to the suction surface 11 of the porous film 10 is secured at the end as well as the central region of the work surface 12. Therefore, the resin 30 suppresses air escape from the side surface 13 to the suction surface 11, and a suction action is obtained over the entire work surface 12. Even if the thickness D of the region 16 in the vicinity of the work surface 12 is very small, it is sufficient for securing the suction path. Specifically, the thickness D is suitably about 0.1 μm to 1 mm.

  The region 16 having the above thickness can be easily formed by, for example, immersing the end of the porous membrane in the filler liquid in a state where a protective film represented by a resin tape is disposed. The protective film prevents the filler liquid from penetrating into the pores in the region 16 in the vicinity of the work surface and secures an air suction path. Thus, by immersing the end of the porous membrane in the filler liquid in a state where the protective member such as a protective film is disposed so as to cover the end of the work surface of the porous membrane, the end of the work surface By preventing the filler liquid from penetrating into the pores in the vicinity of the area, it is possible to secure an air suction path from the end of the work surface to the suction surface of the porous membrane when receiving a suction action from the suction unit. . The protective member is removed from the porous membrane after drying the infiltrated filler liquid.

  Hereinafter, an example of a method for manufacturing the sheet shown in FIG. 2 will be described with reference to FIG. First, as shown in FIG. 3A, the protection member 40 is disposed at the end of the work surface 12 of the porous membrane 10. Next, after immersing each in the filler liquid from the end of the porous membrane 10, the permeated filler liquid is dried. The degree of immersion of the porous membrane 10 in the filler liquid is set to a depth equal to or less than the width of the protective member 40 (the length in the lateral direction in FIG. 3), and the filler liquid is directly applied to the work surface 12 of the porous membrane 10. Avoid contact. As a result, the filler liquid penetrates from the side surface of the porous membrane 10 and the suction surface 11 into the pores at the end, while the penetration of the filler liquid from the work surface 12 into the pores at the end is prevented. However, in the vicinity of the side surface of the end portion of the porous membrane 10, the filler liquid that has permeated from the side surface of the porous membrane 10 may reach the region 16 in the vicinity of the work surface 12. For this reason, when the infiltrated filler liquid is dried, the resin 30 may be filled up to the region 16 in the vicinity of the work surface 12 as shown in FIG. In such a case, the peripheral portion 17 of the porous membrane 10 is excised as shown by a broken line in FIG. 3B to remove the portion filled with the resin 30 up to the work surface 12. The peripheral portion 17 to be excised is suitably about 5 mm from the side surface of the porous membrane 10, for example. As a result, the suction fixing sheet shown in FIG. 3C is formed in which the holes 30 in the end portion 15 are filled with the resin 30 with the region 16 in the vicinity of the work surface 12 left. The protective member 40 is removed from the porous film 10 after the filler liquid is dried.

  When the adsorption conveyance work is repeated, the porous film deteriorates and eventually breaks. From the viewpoint of suppressing the deterioration by maintaining the strength of the membrane, the thickness of the porous membrane is preferably 1.5 mm or more. Although the upper limit of the thickness of a porous membrane is not specifically limited, For example, it may be 5 mm, for example, 10 mm.

  As the porous membrane becomes thicker, the strength is increased and the durability is improved, while air escape from the side surface is also increased. Therefore, the present invention is particularly useful for a porous membrane having a thickness as large as the above.

The porous membrane preferably has an air permeability obtained by the fragile method defined in JIS L 1096 in the range of 0.1 to 4.0 cm ³ / cm ² / sec, 1.0 to 2.5 cm. More preferably, it is in the range of ³ / cm ² / sec. The air permeability of the membrane and the adsorptive power with respect to the article are inversely proportional. When the air permeability of the porous membrane is in the above range, the article can be transported in a firmly adsorbed state, and the article can be easily detached from the suction unit at the transport destination.

  The shape of the adsorption fixing sheet is not particularly limited. What is necessary is just to design suitably according to the shape of the articles | goods of conveyance object, or the shape of a suction unit.

  Hereinafter, the present invention will be described in more detail with reference to examples.

Example 1
UHMWPE powder (GURA4022 manufactured by TICONA: average molecular weight 5 million, bulk density 0.47 g / cm ³ , average particle diameter 180 μm) is filled in a mold and placed in a metal pressure-resistant container, and the inside of the container is decompressed to 1000 Pa. did. Subsequently, heated water vapor was introduced into the mold and heated at 6 atm and 160 ° C. for 5 hours to sinter UHMWPE powder to obtain a cylindrical sintered porous body. The sintered porous body was gradually cooled and then cut using a lathe to obtain a porous film having a thickness of 2.0 mm. This porous membrane was placed in a press machine, held at 130 ° C. for 13 hours under a pressure of 1.9 kgf / cm ² , and then cut into a square plate of 110 mm × 110 mm.

  An aqueous solution containing 10% by weight of polyvinyl alcohol (PVA), water, and ethanol were mixed at a weight ratio of 60:20:20 to prepare a filler solution. One end of the cut porous membrane and the end opposite to the end are dipped in the filler liquid for 10 minutes each for 5 minutes, so that the filler liquid is filled in the pores at each end. Infiltrated. The filler liquid penetrated to a portion about 13 mm away from the side surface of the sheet by capillary action. Then, the sheet | seat was hold | maintained at 80 degreeC for 12 hours in the drying furnace, and the filling of the PVA resin to the void | hole of an edge part was completed. And the sheet | seat for adsorption fixation of 100 mm x 100 mm was obtained by cutting off the peripheral part (width | variety: 5 mm) of a sheet | seat.

  FIG. 4 is a plan view of the suction fixing sheets of Example 1 and Examples 2 to 4 to be described later when viewed from the work surface side. As shown in FIG. 4A, the suction fixing sheet of Example 1 is more specifically an area extending from the side surface of the sheet to a portion about 8 mm away from the side surface in the in-plane direction. The resin 30 is filled in the holes. For this reason, in this suction fixing sheet, air escape from the side surface to the suction surface of the sheet is suppressed for the two end portions 15, and the central region of the work surface when receiving a suction action from the suction unit and Air is sucked into the suction surface of the sheet at the remaining two ends.

(Example 2)
Adhesive tape (Nitto Denko polyimide adhesive tape No. 360) covers one end and the opposite end to the main surface (working surface) on one side of a 110 mm × 110 mm porous membrane. ) Was attached, and an adsorption fixing sheet was obtained in the same manner as in Example 1 except that all the end portions (four end portions) were immersed in the filler liquid. The pressure-sensitive adhesive tape was peeled off from the sheet after the filler liquid was dried and the peripheral portion of the sheet was excised.

  As shown in FIG. 4 (b), this suction fixing sheet has a region 16 in the vicinity of the end 15 of the work surface with respect to the two ends 15 to which the adhesive tape is applied, more specifically, the work surface. The resin 30 is filled in the vacancies of all the end portions 15 while leaving a region about 10 μm away from the substrate. For this reason, in this suction fixing sheet, air leakage from the side surface to the suction surface of the sheet is suppressed at all the end portions, and the two end portions 15 to which the adhesive tape is attached are sucked from the suction unit. When received, air is sucked from the end of the work surface to the suction surface of the sheet.

(Example 3)
An adsorption fixing sheet was obtained in the same manner as in Example 1 except that all the end portions of the 110 mm × 110 mm porous membrane were immersed in the filler liquid. As shown in FIG. 4 (c), this suction fixing sheet is in a state in which the holes 30 are filled with the resin 30 over the entire periphery of the end portion 15 of the sheet. For this reason, in this suction fixing sheet, air leakage from the side surface to the suction surface of the sheet is suppressed for all the end portions 15.

Example 4
Adsorption in the same manner as in Example 2 except that the immersion in the filler liquid was carried out with the polyimide adhesive tape applied so as to cover all the ends of the work surface of the 110 mm × 110 mm porous membrane. A fixing sheet was obtained. As shown in FIG. 4D, the suction fixing sheet has a region 16 in the vicinity of the end 15 of the work surface, more specifically, about 10 μm away from the work surface for all the end portions 15. The resin is filled in the pores with the region left. For this reason, in this suction fixing sheet, air leakage from the side surface to the suction surface of the sheet is suppressed for all the end portions 15, and the suction of the sheet is performed over the entire work surface when receiving a suction action from the suction unit. Air can be sucked into the surface.

(Comparative Example 1)
In the 110 mm × 110 mm porous membrane, an adsorption fixing sheet was obtained in the same manner as in Example 1 except that the peripheral portion (width: 5 mm) was excised without sealing the end.

  For the adsorption and fixing sheets of Examples 1 to 4 and Comparative Example 1, air permeability, thickness, and ultimate pressure by a predetermined test were examined as follows.

[Air permeability]
The air permeability of the sheet for adsorbing and fixing was measured as the air permeability in the thickness direction of the sheet using a Frazier tester (manufactured by TOYOSEIKI) according to the Frazier method defined in JIS L-1096.

[thickness]
Using a micrometer (minimum graduation 0.001 mm), the thickness of the central portion of the suction fixing sheet and the thickness of the peripheral portion (eight locations) of the sheet were measured at approximately equal intervals. The average value of the thicknesses at these nine locations was calculated and displayed as the thickness of the suction fixing sheet.

[Achieved pressure]
Using a suction unit, the ultimate pressure when a resin film (F200H manufactured by Toray DuPont) having a thickness of 100 mm × 100 mm and having a thickness of 50 μm was adsorbed under reduced pressure via an adsorption fixing sheet was measured. As the suction unit, a decompression pump having an intake force of −70 kPa was used with the gas flow rate set to 38.5 SLM. Note that, as the ultimate pressure approaches -70 kPa, the suction-fixing sheet is in a state where the suction force is excellent (the pressure loss is small).

  Table 1 shows the pressure loss calculated from the air permeability, thickness, ultimate pressure, and ultimate pressure of the adsorption fixing sheets of Examples 1 to 4 and Comparative Example 1.

  As shown in Table 1, the pressure fixing sheets of Examples 1 to 4 had less pressure loss than the suction fixing sheet of Comparative Example 1. And the adsorption | suction fixing sheet | seat of Examples 2-4 had especially few pressure losses.

  The adsorption-fixing sheet of the present invention can be suitably applied to an apparatus for conveying an article such as a metal foil, a plastic film, a ceramic green sheet, a display glass substrate, or a semiconductor wafer.

100, 101 Adsorption fixing sheet 10 Porous membrane 11 Upper surface (suction surface)
12 Bottom (work surface)
DESCRIPTION OF SYMBOLS 13 Side surface 15 End part 16 Area | region of the vicinity of the edge part of a working surface 17 Peripheral part 20 Suction unit 21 Article 30 Resin 40 Protection member

Claims (9)

One of the main surfaces is a suction surface that receives a suction action from the suction unit, and the other main surface is a suction fixing sheet made of a porous film that is a work surface disposed toward an article to be sucked. ,
When at least a part of the end of the porous membrane is filled with resin in the pores of the porous membrane and receives a suction action from the suction unit, the suction surface from the side of the porous membrane by the resin Adsorption fixing sheet that prevents air from leaking into the air.   The sheet for adsorbing and fixing according to claim 1, wherein the porous film is composed of a sintered body of ultrahigh molecular weight polyethylene powder.   The sheet for adsorption fixation according to claim 1 or 2, wherein the resin is a water-soluble resin.   The sheet for adsorption fixation according to any one of claims 1 to 3, wherein the resin is filled in the pores over an entire circumference of an end portion of the porous membrane.   At the end of the porous membrane, the resin is filled in the pores while leaving a region in the vicinity of the work surface, and when receiving a suction action from the suction unit, from the end of the work surface The air suction path to the suction surface of the porous membrane is secured, and the resin suppresses air escape from the side surface to the suction surface, and obtains a suction action over the entire work surface. The sheet | seat for adsorption fixation of any one of 1-4.   The sheet for adsorption fixation according to any one of claims 1 to 5, wherein a thickness of the porous membrane is 1.5 mm or more. The air permeability of the porous membrane obtained by the fragile method defined in JIS L 1096 is 0.1 to 4.0 cm ³ / cm ² / sec, according to any one of claims 1 to 6. The sheet for adsorption fixation as described.   The method for producing an adsorption-fixing sheet according to claim 1, wherein at least a part of an end of the porous membrane is immersed in a filler liquid containing a resin, and the porous membrane is emptied at the end. A method for producing a sheet for adsorbing and fixing, comprising: a step of permeating the filler liquid into a hole; and a step of drying the permeated filler liquid and filling the hole with the resin.   By immersing the end of the porous membrane in the filler liquid in a state in which a protective member is disposed so as to cover the end of the work surface of the porous membrane, a void is formed in the region near the end of the work surface. The infiltration of the filler liquid into a hole is prevented, and an air suction path from the end of the working surface to the suction surface of the porous membrane when receiving a suction action from a suction unit is secured. A method for producing the sheet for adsorption and fixation according to claim 8.

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