JP2005059889A - Spacer paper for glass - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a spacer paper for glasses having a non-contamination property and a non-dusting property, which can be applied to, for example, liquid crystal cell glass thin plates or the like by avoiding a dusting property and a contamination property of a space paper that paper pulps have. <P>SOLUTION: This spacer paper is the most suitable spacer paper for glasses to be laminated by intervening the spacer paper between a plurality of the liquid crystal cell glass thin plates having a size of maximum 2,000 × 1,800 mm, specialized in that the material is a cellophane film. In view of the spacer paper contamination, the binder resin is preferably less than 0.01% (measured by JIS-P8205 standard), so that a regular type space paper of less resin content is preferred. The space paper is not specified in thickness in particular, but practically the thickness is around 0.02 mm (30g/m<SP>2</SP>) or 0.035 mm (50g/m<SP>2</SP>). <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a glass slip sheet, and more particularly to a glass slip sheet suitable for a thin glass sheet that requires high dust resistance and antifouling properties such as those handled in a clean room.

  2. Description of the Related Art Conventionally, when a glass plate is transported and stored, a large number of glass plates have been laminated by interposing a paper sheet made by a papermaking method called interleaving paper to protect the glass surface. When interleaving paper is interposed in this way, paper marks and water repellent marks on the glass plate surface and other stains commonly referred to as paper burn (hereinafter referred to as interleaf stain) The surface cleanliness of the glass surface may be hindered.

  When such a phenomenon occurs, it causes problems in use of functional glass as well as defects in appearance. In other words, in the use of glass for electronics substrates, it is necessary to perform metal film deposition, circuit printing, and plating treatment on the surface, but the location where the slippage of the interleaf is caused is a cause of defects in such various processing treatments. Because it becomes.

In order to solve such problems, in the 1980s, methods for reducing the resin content in paper raw materials and improving the hygroscopicity of paper were proposed. In recent years, a method for adding a chemical agent has been proposed in order to further avoid defective slippage of the slip sheet. For example, 0.1 wt% or more of sodium tripolyphosphate is added to the slip sheet (see Patent Document 1), and sodium borate is contained in an amount of 50 mg / m ² or more (see Patent Document 2). The above-described interleaf paper stains can be easily washed and removed, and does not prevent the occurrence of the stains themselves.

The present applicant has proposed a slip sheet for glass that can cope with such a problem. First, it is a method of adding about 0.03 to 0.1 wt% of polyhydric alcohol with limited carbon number to the interleaving paper, and also an alkylene oxide adduct of polyhydric alcohol, improving the hygroscopicity of the interleaving paper. To do. (See Patent Document 3)
Secondly, a method for preventing fouling of slipping paper by extracting a hot water-soluble component is proposed for slipping paper made from mechanical pulp waste paper. (See Patent Document 4)

  By the way, in recent years, as the use of glass has been diversified, further higher cleanliness of the glass surface has been required. For example, the glass thin plate for liquid crystal cells used in liquid crystal displays has not only the non-fouling property such as the paper burn as mentioned above, but also the high dust-free property that can be handled in a clean room. It has come to be required.

  For such applications requiring non-fouling and dust-free properties, there is room for improvement in terms of dust-free properties even in the slip sheet proposed by the applicant of the present application. Further, according to a glass interleaving paper proposed for this purpose (see Patent Document 5), 5 to 40 parts by weight of a resin binder is mixed with 100 parts of natural pulp to make dust-free paper, and water-soluble resin is provided on both sides thereof. It is described that a predetermined amount of is applied.

However, in this slip sheet, a considerable amount of resin binder that causes stains such as paper burns is used, and a water-soluble resin is applied to both sides for slippage stains caused by the resin binder. However, since this water-soluble resin itself can cause dust generation, it is expected that it will be necessary to strictly control the use amount of the resin binder and water-soluble resin. There are circumstances that can be said that there is no problem.
JP-A-6-316432: paragraphs (0005) (0006). Japanese Patent Application Laid-Open No. 7-101483: “Problem Solving Means”, “Action”, etc. JP 7-316998 A: Paragraph (0004). JP 2003-41498 A: “Problem solving means”, “Action”, and the like. JP-A-9-170198: paragraphs (0004) (0005).

  Because of this technical background, at present, spacers are sandwiched between both side edges when laminating thin glass plates for liquid crystal cells that require dust-free properties that can be handled in clean rooms. As a result, if only 50 glass thin plates for liquid crystal cells are laminated, the laminate becomes bulky with a thickness of 50 cm. However, there is a problem that it is difficult to automate the stacking work and the work efficiency is not improved.

  The present invention has been made to solve the above-mentioned problems, avoids the dust generation and interleaf contamination of paper pulp, and has, for example, non-fouling properties that can be applied to glass thin plates for liquid crystal cells. Provided is a glass slip sheet having dust-free properties.

  The above problem can be solved by the glass interleaving paper according to the present invention, which is a glass interleaving paper interposed between a plurality of glass thin plates, and is made of a cellophane film.

  In the present invention, the surface of the cellophane film is formed with fine embosses, the cellophane film is formed with a large number of fine through holes, or the cellophane film is formed with a large number of slits penetrating the front and back. It is preferable that the peelability improving means of the form is formed. Furthermore, it is particularly preferable that these cellophane films do not substantially contain a softening agent, and the glass interleaving paper is particularly preferably used for laminating glass thin plates for liquid crystal cells.

  The cellophane film in the present invention can be produced by the following known production methods. That is, cellulose pulp is treated with an alkali solution such as caustic soda to obtain alkali cellulose, which is aged, and the aged alkali cellulose is dissolved in carbon disulfide to produce viscose (stock solution). In the next film forming step, the viscose is continuously discharged into a film form from an lip called a slit or hopper into an acidic solution, which is continuously solidified to form a film. Subsequently, this is subjected to treatments such as deoxidation treatment, bleaching, washing with water, and a flexible bath, and dried with a mirror drum and wound up to obtain a cellophane film winding roll.

  The glass interleaving paper of the present invention is a glass interleaving paper with a cellophane film instead of the paper produced by paper making of pulp, so that the organic resin component that causes the paper slipping as contained in the paper making paper Since it is made of a uniform film structure, it is not composed of fibrous materials as in the case of papermaking paper, so it essentially has the dust generation and fouling properties of papermaking paper. It was materialized as not having.

  Thus, since there is no risk of dust generation that was unavoidable with paper pulp, handling in a clean room is necessary. For example, it can be effectively applied to lamination of glass thin plates for liquid crystal cells used for liquid crystal displays. . As a result, in place of the conventional stacking method with the spacers interposed, the stacking volume can be reduced to about 1/10.

  Furthermore, when the above-described peelability improving means is provided on the cellophane film of the present invention, or if it does not substantially contain a softening agent, workability such as insertion and removal between glass thin plates for liquid crystal cells is improved. Since it greatly improves, it is easy to automate the laminating / opening operations for laminating and separating the laminating, so that there is an excellent effect that it can greatly contribute to the production efficiency. Therefore, the present invention has a very large industrial value as a slip sheet for glass that has solved the conventional problems.

Next, an embodiment according to the slip sheet for glass of the present invention will be described with reference to the examples.
The interleaving paper for glass of the present invention is the most suitable interleaving glass for interposing and laminating between a plurality of glass thin plates for liquid crystal cells having a maximum size of 2000 × 1800 mm, but is not necessarily limited to this target glass. It is intended for glass plates with dust-free and non-fouling surface accuracy that require handling in a clean room, but it can be applied to glass plates of lower grades. Nor.

  The most characteristic feature is that the material is a cellophane film. Cellophane film is a material made from cellulose pulp that has a homogeneous internal structure as described above. In the process, cellophane film is subjected to treatments such as deoxidation, bleaching and washing to remove components other than cellulose. Therefore, the purity is extremely high.

Cellophane includes a normal type and a moisture-proof type whose surface is coated with a resin, but any of the cellophanes can be applied in the present invention, but the content of resin is 0.01% or less (JIS-P8205) in consideration of fouling of interleaf paper. Therefore, it is preferable to use a normal type that does not contain more resin. The thickness is not particularly limited, but a thickness of about 0.02 mm (30 g / m ² ) or 0.035 mm (50 g / m ² ) is practical.

Next, as a matter of note when cellophane is applied as a slip sheet, there is a point that the operability equal to or higher than that in the case of papermaking can be obtained by laminating and opening glass plates. Cellophane has excellent smoothness compared to papermaking paper, but for this reason, when trying to remove the cellophane film attached to the glass plate, sometimes it is difficult to peel off .
In the present invention, when it is necessary to improve such peelability, the following modes are prepared as means to be adopted.

  The first means among such peelability improving means is to form fine embosses on the surface of the cellophane film with a known embosser or the like. As the embossed shape, irregularities such as a dot shape, a chain line shape, a straight line shape, and a wavy line shape, which are distributed over the entire surface with a height difference of less than 0.1 mm and a pitch of less than 2 mm are suitable. In addition, the embossing of the present invention means fine irregularities on the surface that can improve the peelability, so that it has a level difference and pitch that can be identified with the naked eye, and exhibits a matte appearance that cannot be recognized with the naked eye Including even embossing.

  The second means is a cellophane film in which a number of fine through holes are formed by a known punch or the like, and it is preferable to distribute innumerable pinholes on the surface. In this case as well, as in the first case, the movement of the air at the time of peeling becomes easy, and the peeling property is greatly improved. Further, the third means is a cellophane film in which a number of slits penetrating the front and back are formed by a known slit machine or the like, and since air circulation is easier than in the case of the second means, the slit pitch is large. it can.

  Furthermore, as a matter of note when cellophane is applied as a slip sheet, it is preferable to consider the ease of handling of the cellophane film itself in the operability of laminating and opening the glass plates described above. Specifically, since the flexibility is respected in the general use of the cellophane film, the normal manufacturing method passes a bath of glycerin or the like as a softening agent in the manufacturing process to increase the flexibility of the film. However, this flexibility often has an adverse effect on the operability of glass plate lamination and opening operations required for the glass slip sheet of the present invention.

  From such a point, if the cellophane film in the present invention omits the softening bath impregnated with the softening agent and does not substantially contain the softening agent, the film itself has high rigidity, so-called firmness. Since it becomes a material, an important practicality that handling at the time of lamination or opening becomes easy is improved.

  Next, with respect to the examples and comparative examples of the present invention, comparative tests were performed on the items of fouling test, dust generation property and workability, and the results shown in Table 1 below were obtained. According to this result, in the examples of the present invention, compared with the paper-made interleaving paper manufactured by the conventional papermaking, it is at least equivalent in terms of fouling and workability, and excellent in dust generation far surpassing the papermaking paper. It has been proved that the effects can be obtained. Further, Table 1 does not include an example in which an infinite number of pinholes or slits are provided in the cellophane, but these points show the same performance as the embossed cellophane B.

  In the stain test, a sample of B5 size is sandwiched between glass plates and left for 96 hours at 60 ° C and humidity of 95%, and then the stains on the T surface (front surface) and B surface (back surface) of the glass plate are visually observed. In addition, the exhalation mark generated by blowing exhalation was observed, and then the ease of wiping off the exhalation mark was observed. The results were displayed as ◯: Good, Δ: Practical, ×: Impractical.

  Regarding the dust generation property, a glass thin plate for a liquid crystal cell was set in a clean booth by inserting a test slip sheet into a sealed Alpoly box, and after the transportation test, the particles in the box were measured to determine the number of dust generation. The outline of the test conditions is as follows. Clean booth cleanliness: Class 1000, Alpoli box size: 1000 × 700 × 400 mm, glass thin plate: size: 850 × 560 mm (thickness 0.7 mm) × 25 sheets, test slip: size: 860 × 570 mm × 26 Sheet, particle diameter: 0.3 to 5.0 μm, transport distance of transport test: 300 km. The average fiber length is determined by microscopy.

The workability was evaluated by observing the peeling resistance of the sample attached with the glass plate by a sensory test, and the peeling property was evaluated as follows: ○: good, Δ: practical use, ×: impractical use. Moreover, the automation adaptability was indicated as “◯” for a paper equivalent to the papermaking paper B, and “△” for a slightly inferior product.
The other items were performed according to standards such as JIS and prescribed methods.

Claims (7)

  A glass interleaving paper for interposing between a plurality of glass thin plates, comprising a cellophane film.   2. The interleaving paper for glass according to claim 1, wherein the cellophane film is a film on which a peelability improving means is formed.   The interleaving paper for glass according to claim 2, wherein fine embosses are formed on the surface of the cellophane film as the peelability improving means.   The interleaving paper for glass according to claim 2, wherein a number of fine through-holes are formed in the cellophane film as the peelability improving means.   The interleaving paper for glass according to claim 2, wherein a number of slits penetrating front and back are formed in the cellophane film as the peelability improving means.   The glass interleaf according to any one of claims 1 to 5, wherein the cellophane film does not substantially contain a softening agent.   The glass interleaving paper according to claim 7, wherein the glass interleaving paper is used for a glass thin plate for a liquid crystal cell.