JP2020059966A - Wood pulp for glass plate interleaving paper and glass plate interleaving paper - Google Patents

Abstract

To provide an interleaving paper for a glass plate used as a substrate material for a flat panel display on which a high degree of cleanliness and scratch-free surfaces are required, capable of reducing contamination of the surface of the glass to a level having no practical problem, and wood pulp for the interleaving paper.SOLUTION: Wood pulp for glass plate interleaving paper in which the ratio of talc existing on the surface of handmade paper prepared by the method according to JIS P 8222 is 10 pieces/100 mor less, and interleaving paper for glass plate using wood pulp as a raw material and the interleaving paper for glass plates in which the ratio of talc existing on the surface is 3 pieces/100 mor less.SELECTED DRAWING: None

Description

  The present invention is a paper for packaging glass plates in the process of stacking and storing a plurality of glass plates for a flat panel display such as a liquid crystal display, a plasma display, an organic electroluminescence (organic EL) display, and The present invention relates to paper sandwiched between glass plates, and wood pulp used for manufacturing these papers.

  Generally, in the process of stacking and storing a plurality of glass plates for a flat panel display, in the distribution process of transporting by a truck, etc., the glass plates are impacted and come into contact with each other, causing scratches, and In order to prevent the glass surface from being contaminated, paper called interleaving paper is sandwiched between glass plates.

  Glass plates for flat panel displays are used for high-definition displays as compared with general architectural window glass plates and vehicle window glass plates, so the glass surface contains impurities contained in the paper surface as much as possible. It is required to maintain an unclean surface and to have excellent flatness for high-speed response and widening of the viewing angle.

  As interleaving papers used for such purposes, some have already been proposed as interleaving papers that can prevent cracking of the glass plate and scratches on the surface, and interleaving papers that do not contaminate the glass surface. For example, Patent Document 1 discloses a method of forming a fluorine coating film on the surface of interleaving paper. Further, Patent Document 2 discloses an interleaving paper in which a polyethylene resin foam sheet and a polyethylene resin film are laminated, and Patent Document 3 discloses a paper made of pulp containing 50% by mass or more of exposed chemical pulp. Therefore, a glass interleaving paper containing a specific alkylene oxide adduct or a water-soluble polyether-modified silicone, and in Patent Document 4, the amount of resin in the paper is specified, and the contamination of the glass surface is taken into consideration. Glass sheet interleaving papers using the above raw materials are disclosed. Further, Patent Document 5 proposes to use a cellulose pulp having specific physical properties as a raw material for glass interleaving paper.

  However, these interleaving papers do not completely prevent the contamination of the glass plate surface for flat panel displays, and in some cases, due to the contamination of the glass plate surface for some reason, the defect rate of the glass plate increases. It is the actual situation that there is.

  In particular, recently, from the viewpoint of profitability, a high yield is required in the manufacturing process of flat panel displays and the like, and it is important to prevent contamination of the surface of a glass plate used for flat panel displays.

  Therefore, Patent Document 6 describes limiting the amount of silicone contained in the slip sheet for glass plates.

JP 2012-188785 A JP, 2010-242057, A JP 2008-208478 A JP, 2006-44674, A JP, 2007-131965, A International Publication No. 2014/104187

  However, it may be difficult to reduce the contamination of the glass plate surface derived from silicone to a practically unproblematic level only by limiting the total amount of silicone contained in the glass plate interleaving paper.

  INDUSTRIAL APPLICABILITY The present invention can reduce the contamination of the surface of a glass used as a substrate material for a flat panel display, which requires high cleanliness and scratch quality, to a practically problem-free level. An object of the present invention is to provide an interleaving paper and a wood pulp for the interleaving paper.

  For example, it is known that when the surface of a glass plate is contaminated at the time of manufacturing a color filter substrate in an array process which is one of the manufacturing processes of a TFT liquid crystal display, a problem such as disconnection occurs. The color filter substrate is manufactured by forming a thin film such as a semiconductor film, an ITO film (transparent conductive film), an insulating film, and an aluminum metal film on a glass plate by sputtering or vacuum deposition method. This is because the presence of the wire causes a disconnection in the circuit pattern formed from the thin film or a short circuit due to a defect in the insulating film. Further, in the production of the color filter substrate, a pattern is formed on the glass plate by photolithography, but if contaminants are present on the glass plate surface during resist coating in this process, pinholes will form in the resist film after exposure and development. As a result, disconnection or short circuit occurs. Similar problems have been confirmed in the manufacture of organic EL displays. An organic EL display is manufactured by forming thin films such as an ITO anode, an organic light emitting layer, and a cathode on a glass substrate by sputtering, vapor deposition, printing, or the like, and thus there is no light emission when foreign substances that interfere with the thin film are present on the glass substrate surface. The problem arises.

  The cause of such contamination of the glass plate has been difficult to identify, but it has been revealed by the verification by the present inventors that the cause is a hydrophobic substance such as silicone contained in the interleaving paper for the glass plate.

  Therefore, the total amount of the hydrophobic substances in the wood pulp used in the production of the glass sheet interleaving paper (hereinafter, also referred to as “glass sheet interleaving paper”) is kept below a certain level, and It is conceivable that the total amount of the hydrophobic substance is less than a certain value. However, it may be difficult to reduce the contamination of the glass plate surface due to the hydrophobic substance to a practically unproblematic level only by limiting the total amount of the hydrophobic substance.

  Then, as a result of further earnest studies, the present inventors have found that a hydrophobic substance that appears on the surface of the interleaving paper for a glass plate, or is contained in the wood pulp used for the production of the interleaving paper for a glass plate, may be a problematic substance. It was discovered for the first time that it could be combined with talc. Then, the present inventors finally reduced the amount of talc appearing on the surface of the glass sheet interleaving paper or contained in the wood pulp used in the production of the glass sheet interleaving paper to finally obtain the glass sheet. The present invention has been completed by finding that the problematic hydrophobic substance appearing on the surface of the interleaving paper can be reduced and the above problems can be solved.

  In the first place, talc is widely used to make tacky substances such as pitch contained in wood non-tacky during the production of wood pulp to suppress troubles caused by the tacky substances in the paper manufacturing process. In addition, when used paper is used as a raw material for paper, it is widely used to detackify sticky substances such as resins in the used paper.

  Up until now, talc has been actively used in interleaving paper for glass plates, which is used as a substrate material for flat panel displays that require high cleanliness and scratch quality, in order to eliminate tacky substances that may cause problems. It was thought that it should be compounded. For example, in Patent Document 5 (Japanese Patent Laid-Open No. 2007-131965) (see [0009], [0017], [0032], etc.), the adhesive substance contained in the glass sheet interleaving paper should be made non-adhesive by talc. Is disclosed.

  Therefore, rather than positively using talc, contamination of the surface of the glass is practically a problem for a glass plate used as a substrate material for a flat panel display that requires high cleanliness and scratch quality. It is a surprising finding that it can be reduced to a level not present, and the technical significance of the present invention based on the finding is remarkable in the technical field.

  Then, in the present invention, by limiting the abundance ratio of talc, the abundance ratio of the hydrophobic substance that may be a problem is reduced, and the contamination of the glass plate surface derived from the hydrophobic substance to a practically problem-free level. It can be reduced.

A first aspect of the present invention is a wood pulp for glass sheet interleaving paper, in which the proportion of talc present on the surface of a handmade paper prepared by the method according to JIS P 8222 using the wood pulp is 10 pieces. / 100 m ² It is related to the wood pulp for glass sheet interleaving paper.

  The average particle size of the talc is preferably 1 to 10 μm.

  The talc may be complexed with a hydrophobic substance. In the form in which the talc and the hydrophobic substance are combined, the average particle size is preferably 30 μm or more. The hydrophobic material may include silicone. The silicone is preferably silicone oil. The silicone oil is preferably dimethylpolysiloxane.

  The glass plate is preferably used for a display, and particularly preferably the display is a TFT liquid crystal display or an organic EL display.

A second aspect of the present invention relates to an interleaving paper for glass plates, which is made of wood pulp as a raw material, and in which the ratio of talc present on the surface is 3 pieces / 100 m ² or less.

  The average particle size of the talc is preferably 1 to 10 μm.

  The talc may be complexed with a hydrophobic substance. In the form in which the talc and the hydrophobic substance are combined, the average particle size is preferably 30 μm or more. The hydrophobic material may include silicone. The silicone is preferably silicone oil. The silicone oil is preferably dimethylpolysiloxane.

  The glass plate is preferably used for a display, and particularly preferably the display is a TFT liquid crystal display or an organic EL display.

  Further, the present invention is a glass plate interleaving paper comprising the wood pulp of the first aspect of the present invention, and / or the glass sheet interleaving paper of the second aspect of the present invention, and a laminate with a glass plate. Also related to things.

  The invention further relates to the use of the wood pulp of the first aspect of the invention for the manufacture of glass sheet interleaving paper, in particular the glass sheet interleaving paper of the second aspect of the invention.

  In the present invention, by reducing the amount of talc capable of forming a complex with a hydrophobic substance such as silicone, the hydrophobic substance is complexed with talc and grows to the extent that it may cause a problem, resulting in high cleanliness and scratch quality. It is possible to avoid or reduce contamination of the surface of a glass plate used as a substrate material for a flat panel display, which is required.

  The glass sheet interleaving paper comprising the wood pulp of the present invention and the glass sheet interleaving paper of the present invention can suppress or avoid the transfer of a hydrophobic substance such as silicone to the glass sheet. In this way, by suppressing or avoiding the transfer of the hydrophobic substance to the glass plate, it becomes possible to prevent the circuit breakage of the color film or the like in the manufacturing process of the TFT liquid crystal display or the like.

  In the present invention, the total amount of the hydrophobic substance in the wood pulp used for the production of the glass plate interleaving paper, or, the total amount of the hydrophobic substance in the glass plate interleaving paper is not below a certain level, Since the number of talcs that can be a problematic hydrophobic substance locally present in the wood pulp or on the surface of the interleaving paper for the glass plate is set to a certain value or less, the hydrophobic substance that may be transferred to the glass plate. Can be controlled at an individual level, and it becomes possible to reduce the contamination of the glass plate surface due to the hydrophobic substance to a level at which there is practically no problem.

When a slip sheet is used for a glass plate, a hydrophobic substance such as silicone in the slip sheet tends to be transferred to the glass plate, and in particular, the number of talc present on the surface exceeds 10 pieces / 100 m ^2. If the interleaving paper made of wood pulp that can be prepared or the interleaving paper in which the number of talc present on the surface exceeds 3 pieces / 100 m ² is used for the glass plate, the hydrophobic substance that may be transferred to the glass plate may be a problem. Increased, resulting in problems during panel formation.

Therefore, in the wood pulp for glass sheet interleaving paper of the present invention, the abundance ratio of talc present on the surface of the handmade paper prepared by the method according to JIS P 8222 using the wood pulp is 10 pieces / 100 m ² or less. is there. Moreover, the slip sheet for glass plates of the present invention is a slip sheet for glass made of wood pulp, and the abundance ratio of talc present on the surface is 3 pieces / 100 m ² or less. This reduces the number of substantially problematic areas of hydrophobic substances such as silicone present on the surface of the glass sheet interleaving paper of the present invention or the glass interleaving paper of the present invention to a non-problematic level. can do.

The number of talc present on the surface of the handsheets is preferably at 8 / 100m ² or less, more preferably 6 / 100m ² or less, still be at 4 / 100m ² or less than preferably, it is preferred even more that two / 100m ² or less, preferably more than that one / 100m ² or less, and particularly preferably 0.5 or / ^{m 2} or less.

Preferably talc number present on the surface of the glass plate for slip sheet is two / 100m ² or less, more preferably 1 / 100m ² or less, 0.8 or / 100m ² or less It is even more preferable that the number is 0.6 / 100 m ² or less, still more preferably 0.4 / 100 m ² or less, and 0.2 / 100 m ² or less. Is particularly preferable.

  By the way, an organic substance that can be extracted from pulp with an organic solvent is referred to as "pitch". The pitch is mainly composed of fatty acids such as palmitic acid and stearic acid, and resin acids such as abietic acid and pimaric acid, and also includes ester compounds and the like. In the case of waste paper pulp, there are also components derived from sizing agents, hot melt resins, inks and the like. If these pitches are included in the paper, it may cause inconvenience such as paper break. The pitch control agent has a function of suppressing the pitch. For example, it reduces the tackiness of the pitch, prevents its aggregation and growth, and causes the pitch to be retained in the paper in a harmless manner.

  That is, the pitch control agent is an additive used for detackifying tacky substances such as pitch in the paper manufacturing process. The pitch control agent is also used, for example, to suppress a pitch adhesion trouble during a papermaking process caused by a resin component (pitch) contained in wood or waste paper which is a raw material of paper. In the pulp manufacturing process, the pitch control agent is used in a non-bleaching cleaning process, a bleaching process, a selection process, a deinking process and the like.

  Since talc is relatively inexpensive, it is widely used as a pitch control agent. In addition, talc is used not only as a pitch control agent but also as a filler and a pigment for paper coating, and exhibits the effects of improving the whiteness of paper and printing characteristics.

The talc in the present invention is not particularly limited. Talc is called "hydrous magnesium silicate", and its chemical formula can be represented by 4SiO ₂ .3MgO.H ₂ O. The chemical composition is slightly different depending on the place of origin, and the theoretical value is a weight ratio of SiO ₂ 64.4%, MgO 31.8%, and ignition loss (water content) 4.7%. Talc is also called talc.

  The surface of talc is relatively lipophilic, and it can be combined with a hydrophobic substance by adsorbing a hydrophobic substance such as silicone in pulp slurry. Therefore, talc can adsorb a hydrophobic substance such as silicone even in water to reduce its tackiness. The form of complexing talc and a hydrophobic substance, particularly silicone, is not particularly limited, but at least a part of talc may be coated with a hydrophobic substance, or at least a part of talc may have a hydrophobic substance. It may penetrate.

  The average particle diameter of the talc is not particularly limited, but is preferably 1 to 10 μm, more preferably 1 to 8 μm, even more preferably 1 to 6 μm, and particularly preferably 1 to 4 μm. The average particle diameter may be a volume average particle diameter, and can be measured, for example, by a laser diffraction / scattering method.

The surface area of the talc is not particularly limited, but the specific surface area by the BET method is preferably 1 m ² / g or more, more preferably 10 m ² / g or more, even more preferably 20 m ² / g or more.

  The density of the talc is not particularly limited, but the apparent density based on JIS K5101 is preferably 1 g / ml or less, more preferably 0.8 g / ml or less, even more preferably 0.6 g / ml or less, and 0.4 g / ml. It is even more preferably not more than ml, and even more preferably not more than 0.2 g / ml.

The abundance ratio of talc present on the surface of the handmade paper prepared by the method according to JIS P 8222 using the wood for glass plate interleaving paper of the present invention is 10 pieces / 100 m ² or less, and the glass plate of the present invention The means for controlling the existence ratio of talc present on the surface of the interleaving paper to 3 pieces / 100 m ² or less is not particularly limited, but a pitch control agent other than talc is used in the papermaking process. Preferably.

  Examples of the non-talc pitch control agent include surfactants, cationic polymers, sulfuric acid bands, and the like.

  As the surfactant, various anionic, cationic, amphoteric and nonionic surfactants can be used, and nonionic surfactants such as polyoxyethylene alkyl ether and polyoxyethylene alkylphenyl ether. Anionic surfactants such as sodium dialkyl sulfosuccinate and sodium alkylbenzene sulfonate are preferred.

で表される単位を含むジアリル第４級アンモニウムポリマー、下記一般式（２）：

で表される単位を含むキトサン、下記一般式（３）：

（式中、Ｒ_１は水素原子又はメチル基を表し；Ｒ_２及びＲ_３はそれぞれ独立してＣ_１−４アルキル基を表す）で表される単位又はその第４級塩（塩酸塩、硫酸塩等）の形態を含む、ジアルキルアミノ（メタ）アクリレート系ポリマー、下記一般式（４）：

（式中、Ｒ_１及びＲ_２はそれぞれ独立して水素原子又はＣ_１−４アルキル基を表す）で表される単位を含むエピクロルヒドリンアルキルアミン付加型ポリマー、下記一般式（５）：

で表される単位を含むビニルイミダゾリン系ポリマー等が挙げられる。 Various kinds of cationic polymers can be used, and for example, the following general formula (1):

A diallyl quaternary ammonium polymer containing a unit represented by the following general formula (2):

Chitosan containing a unit represented by the following general formula (3):

(In the formula, R ₁ represents a hydrogen atom or a methyl group; R ₂ and R ₃ each independently represent a C _1-4 alkyl group) or a quaternary salt thereof (hydrochloride, sulfuric acid). A dialkylamino (meth) acrylate-based polymer including the form of a salt, etc., and the following general formula (4):

(In the formula, R ₁ and R ₂ each independently represent a hydrogen atom or a C _1-4 alkyl group), an epichlorohydrin alkylamine addition type polymer containing a unit represented by the following general formula (5):

A vinyl imidazoline-based polymer having a unit represented by

  The shape of the region of the hydrophobic substance such as silicone existing on the surface of the glass sheet interleaving paper made of the wood pulp of the present invention is arbitrary, and may be various shapes such as a circle, an ellipse and a square, but a circle. Alternatively, it is preferably oval.

The wood pulp for glass sheet interleaving paper of the present invention has 50/1000 m of hydrophobic substance regions having a minimum diameter of 30 μm or more existing on the surface of handmade paper prepared by a method according to JIS P 8222 using the wood pulp. It is preferable to have a quality of ² or less. The interleaving paper for glass plates of the present invention is a interleaving paper for glass made of wood pulp, and it is preferable that there are 15/1000 m ² or less hydrophobic substance regions having a minimum diameter of 30 μm or more present on the surface.

The number of the hydrophobic material region of the handsheets is preferably 30 or / 1000 m ² or less, more preferably 20 pieces / 1000 m ² or less, still more preferably 10 pieces / 1000 m ² or less , even more preferably from 5/1000 m ² or less, preferably even more that three / 1000 m ² or less, particularly preferably 1/1000 m ² or less. Further, the number of the hydrophobic substance regions is preferably 10 pieces / 10 kg or less, more preferably 6 pieces / 10 kg or less, and more preferably 4 pieces / 10 kg or less per weight of the wood pulp for glass plate interleaving paper. Is more preferable, 3 pieces / 10 kg or less is still more preferable, 2 pieces / 10 kg or less is still more preferable, and 1 piece / 10 kg or less is particularly preferable. The weight here refers to the weight of air-dried pulp.

The number of the hydrophobic material region of the interleaf paper for the glass plate is preferably at 12/1000 m ² or less, more preferably 10/1000 m ² or less, it is 8/1000 m ² or less even more preferably, it is yet more preferred that 5/1000 m ² or less, preferably more than that three / 1000 m ² or less, particularly preferably 1/1000 m ² or less. Further, the number of the hydrophobic substance regions is preferably 4 pieces / 10 kg or less, more preferably 3 pieces / 10 kg or less, and more preferably 2 pieces / 10 kg or less, based on the weight of the interleaving paper for glass plate. It is even more preferably 1 piece / 10 kg or less, even more preferably 0.5 piece / 10 kg or less, and particularly preferably 0.1 piece / 10 kg or less. The weight here refers to the weight of the interleaving paper containing 10% by weight of water.

  The minimum diameter of the hydrophobic substance region is preferably 25 μm or more, more preferably 20 μm or more, even more preferably 15 μm or more, even more preferably 10 μm or more, still more preferably 5 μm or more, still more preferably 1 μm or more, and 0. 5 μm or more is particularly preferable. For example, when the hydrophobic substance region has an elliptical shape, the major axis is preferably 25 μm or more, more preferably 20 μm or more, even more preferably 15 μm or more, still more preferably 10 μm or more, still more preferably 5 μm or more, and 1 μm or more. Is even more preferable, and 0.5 μm or more is particularly preferable. When the hydrophobic substance region is non-circular or non-elliptical, the area circle equivalent diameter is preferably 25 μm or more, preferably 20 μm or more, more preferably 15 μm or more, still more preferably 10 μm or more, still more preferably 5 μm or more. Is more preferable, 1 μm or more is still more preferable, and 0.55 m or more is particularly preferable.

  The maximum diameter of the hydrophobic substance region is preferably 10 mm or less, more preferably 5 mm or less, even more preferably 3 mm or less, even more preferably 1 mm or less, even more preferably 500 μm or less, still more preferably 100 μm or less, and 50 μm or less. Is particularly preferable. For example, when the hydrophobic substance region is elliptical, the major axis is preferably 10 mm or less, more preferably 5 mm or less, even more preferably 3 mm or less, still more preferably 1 mm or less, and 500 μm or less. Even more preferably, 100 μm or less is even more preferable, and 50 μm or less is particularly preferable. When the hydrophobic substance region is non-circular or non-elliptical, the area circle equivalent diameter is preferably 10 mm or less, preferably 5 mm or less, more preferably 3 mm or less, still more preferably 1 mm or less, further preferably 500 μm or less. Is more preferable, 100 μm or less is still more preferable, and 50 μm or less is particularly preferable.

  It is preferable that the surface of the wood pulp for glass sheet interleaving paper of the present invention and the surface of the glass sheet interleaving paper of the present invention do not have a hydrophobic substance region having a maximum diameter exceeding 10 mm.

  The hydrophobic substance is not particularly limited. The hydrophobic substance is preferably non-volatile, and includes an aliphatic hydrocarbon, a vegetable oil, an animal oil, a synthetic glyceride, an aliphatic alcohol, a fatty acid, an ester of an aliphatic alcohol and / or a fatty acid, a resin (excluding silicone), and More preferably, it is selected from the group consisting of silicones, and in particular it is even more preferred that it comprises or is silicone.

  Examples of the aliphatic hydrocarbons include linear or branched hydrocarbons, particularly mineral oil (liquid paraffin, etc.), paraffin, petrolatum, petrolatum, naphthalene, etc .; hydrogenated polyisobutene, isoeicosane, polydecene, pearl lime, etc. Mention may be made of added polyisobutene and decene / butene copolymers; and mixtures thereof.

As examples of other aliphatic hydrocarbons there may also be mentioned C ₆ -C ₁₆ lower alkanes, which are straight-chain or branched or optionally cyclic. Examples that may be mentioned include hexane, undecane, dodecane, tridecane and isoparaffins such as isohexadecane and isodecane.

  Examples of vegetable oils include, for example, flaxseed oil, camellia oil, macadamia nut oil, sunflower oil, apricot oil, soybean oil, arara oil, hazelnut oil, corn oil, mink oil, olive oil, avocado oil, southern oil, castor oil. , Safflower oil, jojoba oil, sunflower oil, almond oil, grape seed oil, sesame oil, soybean oil, peanut oil, and mixtures thereof.

  Examples of animal oils may include, for example, squalene, perhydrosqualene and squalane.

  Examples of synthetic glycerides include, for example, caprylic / capric triglyceride.

  Fatty acids should be in acidic form (ie not in salt form to avoid soaping) and may be saturated or unsaturated and have 6 to 30 carbon atoms, especially 9 to 30 carbon atoms. Containing atoms, optionally substituted, especially with one or more hydroxyl groups (especially 1 to 4). If the fatty acid is unsaturated, the compound may contain 1 to 3 conjugated or non-conjugated carbon-carbon double bonds. The fatty acid is selected, for example, from myristic acid, palmitic acid, stearic acid, behenic acid, oleic acid, linoleic acid, linolenic acid and isostearic acid.

The term "aliphatic alcohol" as used herein, refers to a linear or branched C ₈ -C ₃₀ alcohol in any saturated, optionally, in particular one or more hydroxyl groups ( In particular, 1 to 4) are substituted.

Among aliphatic _alcohols, C 12 _{-C 22} fatty alcohols are _preferred, C 16 _{-C 18} saturated aliphatic alcohols are more preferred. Among these, lauryl alcohol, cetyl alcohol, stearyl alcohol, isostearyl alcohol, oleyl alcohol, behenyl alcohol, undecyl alcohol, myristyl alcohol, and mixtures thereof can be mentioned.

Examples of esters of fatty acids and / or aliphatic alcohols include saturated or unsaturated, straight-chain or branched C _{1 to} C ₂₆ aliphatic mono- or polyacid esters, and saturated or unsaturated, straight-chain esters. Mention may be made in particular of esters of branched or branched C ₁ -C ₂₆ aliphatic monohydric alcohols or polyhydric alcohols, the total carbon number of the esters being preferably 10 or more.

  The resin (excluding silicone) is not particularly limited as long as it is hydrophobic. Examples of the resin include thermoplastic resins such as polyolefin, polystyrene, poly (meth) acrylate, polyacrylamide, polyvinyl chloride, polyvinylidene chloride, polyacrylonitrile, polyester, polycarbonate, polyamide, and polyimide, polyurethane, melamine resin, urea resin. And thermosetting resins, and mixtures thereof.

Examples of the silicone include silicone oil. Silicone oil is hydrophobic, and its molecular structure may be cyclic, linear, or branched. Kinematic viscosity at 25 ° C. of the silicone oil is usually in the range of 0.65~100,000mm ² / s, it may be in the range of ^{0.65~10,000mm} 2 / s.

  Examples of silicone oils include linear organopolysiloxanes, cyclic organopolysiloxanes, and branched organopolysiloxanes.

Ｒ^１ _{（４−ｃ）}Ｓｉ（ＯＳｉＲ^１ _３）_ｃ （３）

（式中、
Ｒ^１は、それぞれ独立して、水素原子、水酸基、或いは、置換若しくは非置換の一価炭化水素基、アルコキシ基で示される基から選択される基であり、
ａは、０〜１０００の整数であり、
ｂは３〜１００の整数であり、
ｃは１〜４の整数、好ましくは２〜４の整数である）
で表されるオルガノポリシロキサンが挙げられる。 Examples of the straight chain organopolysiloxane, the cyclic organopolysiloxane, and the branched organopolysiloxane include, for example, the following general formulas (1), (2), and (3):

_{^{R 1 3 SiO- (R 1 2}} SiO) a -SiR 1 3 (1)

R ¹ _(4-c) Si (OSiR ¹ ₃ ) _c (3)

(In the formula,
R ¹ is independently a group selected from a hydrogen atom, a hydroxyl group, or a substituted or unsubstituted monovalent hydrocarbon group or a group represented by an alkoxy group,
a is an integer of 0 to 1000,
b is an integer of 3 to 100,
c is an integer of 1 to 4, preferably an integer of 2 to 4)
The organopolysiloxane represented by

  The substituted or unsubstituted monovalent hydrocarbon group is typically a substituted or unsubstituted one having 1 to 30 carbon atoms, preferably 1 to 10 carbon atoms, and more preferably 1 to 4 carbon atoms. A valent saturated hydrocarbon group; a substituted or unsubstituted monovalent unsaturated hydrocarbon group having 2 to 30 carbon atoms, preferably 2 to 10 carbon atoms, more preferably 2 to 6 carbon atoms; carbon atom It is a monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms, and more preferably 6 to 12 carbon atoms.

  Examples of the monovalent saturated hydrocarbon group having 1 to 30 carbon atoms include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group. A linear or branched alkyl group such as a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, and a decyl group, and a cycloalkyl group such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group. Can be mentioned.

  Examples of the monovalent unsaturated hydrocarbon group having 2 to 30 carbon atoms include vinyl group, 1-propenyl group, allyl group, isopropenyl group, 1-butenyl, 2-butenyl group, pentenyl group, hexenyl group and the like. Linear or branched alkenyl group; cycloalkenyl group such as cyclopentenyl group, cyclohexenyl group; cycloalkenylalkyl group such as cyclopentenylethyl group, cyclohexenylethyl group, cyclohexenylpropyl group; and ethynyl group, propargyl group And alkynyl groups such as groups.

  Examples of the monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms include aryl groups such as phenyl group, tolyl group, xylyl group and mesityl group. A phenyl group is preferred. In addition, in the present specification, the aromatic hydrocarbon group includes a group composed of an aromatic hydrocarbon and an aliphatic saturated hydrocarbon, in addition to a group composed of only an aromatic hydrocarbon. Examples of the group in which an aromatic hydrocarbon and a saturated hydrocarbon are combined include an aralkyl group such as a benzyl group and a phenethyl group.

  The hydrogen atom on the above monovalent hydrocarbon group may be substituted with one or more substituents, and the substituent includes, for example, a halogen atom (fluorine atom, chlorine atom, bromine atom and iodine atom), a hydroxyl group. , A carbinol group, an epoxy group, a glycidyl group, an acyl group, a carboxyl group, an amino group, a methacryl group, a mercapto group, an amide group, an oxyalkylene group and the like. Specifically, 3,3,3-trifluoropropyl group, 3-chloropropyl group, 3-hydroxypropyl group, 3- (2-hydroxyethoxy) propyl group, 3-carboxypropyl group, 10-carboxydecyl group , 3-isocyanatopropyl group and the like.

  Examples of the alkoxy group include a methoxy group, an ethoxy group and a propoxy group, but a methoxy group or an ethoxy group is preferable, and a methoxy group is more preferable.

  More specifically, the linear organopolysiloxane may be a dimethylpolysiloxane having a trimethylsiloxy group blocked at both ends of its molecular chain (low viscosity such as 2 mPa · s or 6 mPa · s to high viscosity dimethyl silicone such as 1 million mPa · s). ), Organohydrogenpolysiloxane, trimethylsiloxy group-blocked methylphenylpolysiloxane at both molecular chain ends, dimethylsiloxy group-blocked dimethylsiloxane-methylphenylsiloxane copolymer at both molecular chain ends, trimethylsiloxy group-blocked diphenylpolysiloxane at both molecular chain ends , Dimethylsiloxy group-blocked dimethylsiloxane / diphenylsiloxane copolymer at both molecular chain ends, trimethylpentaphenyltrisiloxane, phenyl (trimethylsiloxy) siloxane, trimethylsiloxy group-blocked methyl end at both molecular chain ends Alkylpolysiloxane, dimethylsiloxysiloxane / methylalkylsiloxane copolymer capped with trimethylsiloxy groups at both molecular chain terminals, dimethylsiloxane / methyl (3,3,3-trifluoropropyl) siloxane copolymer, trimethylsiloxy group capped with both molecular chain terminals , Α, ω-dihydroxypolydimethylsiloxane, α, ω-diethoxypolydimethylsiloxane, 1,1,1,3,5,5,5-heptamethyl-3-octyltrisiloxane, 1,1,1,3, 5,5,5-heptamethyl-3-dodecyltrisiloxane, 1,1,1,3,5,5,5-heptamethyl-3-hexadecyltrisiloxane, tristrimethylsiloxymethylsilane, tristrimethylsiloxyalkylsilane, tetrakis Trimethylsiloxysilane, tetramethyl-1,3- Examples include hydroxydisiloxane, octamethyl-1,7-dihydroxytetrasiloxane, hexamethyl-1,5-diethoxytrisiloxane, hexamethyldisiloxane, octamethyltrisiloxane, higher alkoxy-modified silicone, higher fatty acid-modified silicone, dimethiconol and the like. It

  As the cyclic organopolysiloxane, hexamethylcyclotrisiloxane (D3), octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), dodecamethylcyclohexasiloxane (D6), 1,1-diethylhexamethyl Cyclotetrasiloxane, phenylheptamethylcyclotetrasiloxane, 1,1-diphenylhexamethylcyclotetrasiloxane, 1,3,5,7-tetravinyltetramethylcyclotetrasiloxane, 1,3,5,7-tetramethylcyclotetrasiloxane Siloxane, 1,3,5,7-tetracyclohexyltetramethylcyclotetrasiloxane, tris (3,3,3-trifluoropropyl) trimethylcyclotrisiloxane, 1,3,5,7-tetra (3-methacryloxypro) ) Tetramethylcyclotetrasiloxane, 1,3,5,7-tetra (3-acryloxypropyl) tetramethylcyclotetrasiloxane, 1,3,5,7-tetra (3-carboxypropyl) tetramethylcyclotetrasiloxane 1,3,5,7-tetra (3-vinyloxypropyl) tetramethylcyclotetrasiloxane, 1,3,5,7-tetra (p-vinylphenyl) tetramethylcyclotetrasiloxane, 1,3,5,5 7-tetra [3- (p-vinylphenyl) propyl] tetramethylcyclotetrasiloxane, 1,3,5,7-tetra (N-acryloyl-N-methyl-3-aminopropyl) tetramethylcyclotetrasiloxane, 1 , 3,5,7-Tetra (N, N-bis (lauroyl) -3-aminopropyl) tetramethylcyclo Examples include rotetrasiloxane.

  Examples of the branched organopolysiloxane include methyltristrimethylsiloxysilane, ethyltristrimethylsiloxysilane, propyltristrimethylsiloxysilane, tetrakistrimethylsiloxysilane, and phenyltristrimethylsiloxysilane.

  As the silicone oil in the present invention, dimethylpolysiloxane, diethylpolysiloxane, methylphenylpolysiloxane, polydimethyl-polydiphenylsiloxane copolymer, polymethyl-3,3,3-trifluoropropylsiloxane and the like are preferable. Dimethyl polysiloxane is typical as the silicone in the present invention.

  The silicone oil in the present invention may be a modified silicone oil. Examples of the modified silicone oil include polyoxyalkylene-modified silicone oil.

  The polyoxyalkylene-modified silicone oil is a silicone oil in which a polyoxyalkylene group is bonded in the molecule through a silicon-carbon bond, and is preferably water-soluble at room temperature, specifically 25 ° C. However, it is more preferably a nonionic type.

The polyoxyalkylene-modified silicone oil is, for example, a copolymer of a silicone oil composed of linear or branched siloxane and polyoxyalkylene, and there are various ones. ) Is preferable.

R ² ₃ SiO- (R ¹ ₂ SiO) _d- (R ¹ ASiO) _e -SiR ² ₃ (4)

(In the formula,
R ^1's are each independently the same as defined above,
R ² is each independently R ¹ or A,
A is each independently a group represented by R ³ G, R ³ is a substituted or unsubstituted divalent hydrocarbon group, and G is a carbon number of 2 to 5 such as ethylene oxide and propylene oxide. Represents a polyoxyalkylene group containing at least one alkylene oxide of
d represents an integer of 1 to 500,
e represents an integer of 1 to 50).

  Examples of the substituted or unsubstituted divalent hydrocarbon group include a linear or branched divalent hydrocarbon group having 1 to 30 carbon atoms, and specific examples thereof include a methylene group, a dimethylene group and trimethylene. Group, tetramethylene group, pentamethylene group, hexamethylene group, heptamethylene group, octamethylene group, etc., straight or branched alkylene group having 1 to 30 carbon atoms; vinylene group, arylene group, butenylene group, Alkenylene group having 2 to 30 carbon atoms such as hexenylene group and octenylene group; arylene group having 6 to 30 carbon atoms such as phenylene group and diphenylene group; alkylenearylene group having 7 to 30 carbon atoms such as dimethylenephenylene group And a hydrogen atom bonded to a carbon atom of these groups is at least partially a halogen atom such as fluorine, a hydroxyl group, or , Carbinol group, epoxy group, a glycidyl group, an acyl group, a carboxyl group, an amino group, a methacryl group, a mercapto group, an amide group, and substituted groups in the organic group containing an oxyalkylene group or the like. The divalent hydrocarbon group is preferably an alkylene group having 1 to 30 carbon atoms, preferably an alkylene group having 1 to 6 carbon atoms, and more preferably an alkylene group having 3 to 5 carbon atoms.

（式中、
ｘは２０〜１６０、ｙは１〜２５であり、ｘ／ｙの値は５０〜２であり、
Ａは、例えば−（ＣＨ_２）_３Ｏ−（ＣＨ_２ＣＨ_２Ｏ）_ｍ−（ＣＨ_２ＣＨ_２ＣＨ_２Ｏ）_ｎ−Ｒ^４であり、ｍは７〜４０、ｎは０〜４０、ｍ＋ｎの値は少なくとも１であり、グラフト重合されたものでもランダム重合されたものでもよく、Ｒ^４は水素原子又は上記置換若しくは非置換の一価炭化水素基を表す。好適には、ｍは７〜３０、ｎは０〜３０である） For example, the following may be mentioned as specific examples of the polyoxyalkylene-modified silicone oil.

(In the formula,
x is 20 to 160, y is 1 to 25, and the value of x / y is 50 to 2,
A, for example _{- (CH 2) 3 O- (} CH 2 CH 2 O) m - is _{(CH 2 CH 2 CH 2 O} ) n -R 4, m is 7 to 40, n is 0 to 40, m + n Has a value of at least 1, and may be graft-polymerized or random-polymerized, and R ⁴ represents a hydrogen atom or the above substituted or unsubstituted monovalent hydrocarbon group. Suitably, m is 7-30 and n is 0-30).

  Examples of the modified silicone oil include aminoalkyl modified silicone oil.

  The aminoalkyl-modified silicone oil is a silicone oil having an aminoalkyl group bonded to the molecule through a silicon-carbon bond, and preferably has a viscosity of 10 to 100000 cs at room temperature, specifically 25 ° C. Is.

As the aminoalkyl silicone oil, in the above formula (4), G is represented by the formula:-(NR ⁴ CH ₂ CH ₂ ) _z NR ⁴ ₂ (in the formula, R ⁴ is each independently as described above, z Is a number of 0 ≦ z ≦ 4).

  In the present invention, the amount of silicone contained in the wood pulp, and further in the glass sheet interleaving paper made of the wood pulp, is preferably 0.5 ppm or less based on the absolutely dry mass of the wood pulp or interleaving paper, and 0 It is more preferably 0.4 ppm or less, still more preferably 0.3 ppm or less, even more preferably 0.2 ppm or less, and particularly preferably 0.1 ppm or less. When the amount of silicone exceeds 0.5 ppm, in a scene where a very high-definition display is required such as a mobile terminal, the broken portion of the color film caused by the minute amount of silicone transferred to the glass is highly vivid. This is because there is a high possibility that it will be conspicuous and judged to be defective in quality. In addition, in the present invention, “absolutely dry” means a state in which water is not substantially present in the object to be dried by drying, and for example, at room temperature (25 ° C.) of the “absolutely dry” object. The weight change per hour is 1% or less, preferably 0.5% or less, more preferably 0.1% or less.

  In general, wood pulp often contains silicone. This is because a silicone-based defoaming agent is often used as a defoaming agent used in the production process of wood pulp, particularly in a washing process, to prevent a decrease in detergency due to generation of bubbles. The agent-derived silicone remains in the pulp. The silicone antifoaming agent is produced, for example, by mixing a mixture of silicone oil and hydrophobic silica with a modified silicone, a surfactant and the like.

Therefore, in order to reduce the number of hydrophobic substance regions having a minimum diameter of 30 μm or more present on the surface of the glass sheet interleaving paper of the present invention to 15 pieces / 1000 m ² or less, the wood pulp as a raw material of the interleaving paper contains a large amount of silicone. It is important not to include. In the first aspect of the present invention, the means for reducing the content of silicone in the wood pulp, which is the raw material for the interleaving paper, is not particularly limited, but a non-silicone-based defoaming agent used during the production of wood pulp. Preference is given to using defoamers.

  Examples of the non-silicone antifoaming agent include mineral oil antifoaming agents, higher alcohol antifoaming agents, fatty acid antifoaming agents, fatty acid ester antifoaming agents, amide antifoaming agents, amine antifoaming agents. , Phosphoric acid ester type defoaming agents, metal soap type defoaming agents, sulfonic acid ester type defoaming agents, polyether type defoaming agents and vegetable oil type defoaming agents.

  The mineral oil-based defoaming agent includes, for example, mineral oil such as hydrocarbon oil and mineral wax.

  The higher alcohol antifoaming agent includes, for example, octyl alcohol, hexadecyl alcohol and the like.

  The fatty acid-based antifoaming agent includes, for example, palmitic acid, oleic acid, stearic acid and the like.

  The fatty acid ester-based defoaming agent includes, for example, isoamyl stearate, glycerin monoricinolate, sorbitol monolaurate, soribitol trioleate, and the like.

  The amide-based defoaming agent includes, for example, acrylate polyamine and the like.

  The amine-based defoaming agent includes, for example, diallylamine and the like.

  The phosphate ester defoaming agent includes, for example, tributyl phosphate, sodium octyl phosphate and the like.

  The metal soap type defoaming agent includes, for example, aluminum stearate, calcium stearate, potassium oleate and the like.

  The sulfonate ester defoaming agent includes, for example, sodium lauryl sulfonate, sodium dodecyl sulfonate and the like.

  Examples of the polyether antifoaming agent include polyoxyalkylenes such as (poly) oxyethylene (poly) oxypropylene adducts; diethylene glycol heptyl ether, polyoxyethylene oleyl ether, polyoxypropylene butyl ether, polyoxyethylene polyoxypropylene. (Poly) oxyalkylene alkyl ethers such as 2-ethylhexyl ether, higher alcohols having 8 or more carbon atoms and oxyethyleneoxypropylene adducts to secondary alcohols having 12 to 14 carbon atoms; polyoxypropylene phenyl ether, polyoxy (Poly) oxyalkylene (alkyl) aryl ethers such as ethylenenonylphenyl ether; 2,4,7,9-tetramethyl-5-decyne-4,7-diol, 2,5-dimethyl-3-hexyl Acetylene ethers obtained by addition-polymerizing alkylene oxides to acetylene alcohols such as benzene-2,5-diol and 3-methyl-1-butyn-3-ol; diethylene glycol oleate, diethylene glycol lauryl ester, ethylene glycol distearate. And the like (poly) oxyalkylene fatty acid esters; polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan trioleate, and other (poly) oxyalkylene sorbitan fatty acid esters; polyoxypropylene methyl ether sodium sulfate, polyoxyethylene (Poly) oxyalkylene alkyl (aryl) ether sulfate ester salts such as sodium dodecylphenol ether sulfate; (Poly) oxyethylene Stearylphosphate esters of (poly) oxyalkylene alkyl phosphoric acid esters; polyoxyethylene such as polyoxyethylene lauryl amine (poly) oxyalkylene alkyl amines; containing polyoxyalkylene amide.

  The vegetable oil-based defoaming agent includes, for example, vegetable oils such as soybean oil, corn oil, coconut oil, linseed oil, rapeseed oil, cottonseed oil, sesame oil, castor oil and the like.

  Further, the non-silicone antifoaming agent can include inorganic particles such as hydrophobic silica. As the hydrophobic silica, it is preferable to use silica that has been hydrophobized by substituting a silanol group of hydrophilic silica with an alkyl group such as a methyl group.

  The non-silicone defoaming agent may contain a surfactant and the like, if necessary. Therefore, the non-silicone antifoaming agent may be an emulsion type.

The wood pulp for glass sheet interleaving paper of the present invention is a glass plate in which the ratio of talc present on the surface of handmade paper prepared by the method according to JIS P 8222 using the wood pulp is 10 pieces / 100 m ² or less. Wood pulp for interleaving paper. Thereby, for example, the number of regions having a minimum diameter of 30 μm or more of the hydrophobic substance such as silicone existing on the surface of the glass sheet interleaving paper made of the wood pulp of the present invention can be set to, for example, 15 pieces / 1000 m ² or less. .

 The wood pulp that can be used in the present invention is a bleached softwood kraft pulp (NBKP), a bleached hardwood kraft pulp (LBKP), a bleached softwood sulphite pulp (NBSP), a bleached sulphite hardwood (LBSP), a thermomechanical pulp (TMP). Wood pulp such as the above is used alone or in a mixture. Mainly this wood pulp, if necessary, hemp, bamboo, straw, kenaf, mulberry, non-wood pulp such as Sanpei and cotton, cationized pulp, modified pulp such as mercerized pulp, rayon, vinylon, nylon, Synthetic fibers such as acrylic and polyester, chemical fibers, or microfibrillated pulp can be used alone or in combination. However, if the resin content is high in the pulp, the resin content may have an adverse effect such as soiling the surface of the glass plate.Therefore, use chemical pulp with as little resin content as possible, for example, softwood bleached kraft pulp alone. Preferably. Further, a high-yield pulp such as groundwood pulp is not preferable because it contains a large amount of resin. It should be noted that mixing synthetic fibers and chemical fibers improves the sharpening property and improves the workability when lithographically converting the interleaving paper, but recyclability deteriorates in terms of waste treatment, so caution is required. .

 Further, as far as the performance of the present invention is not impaired, with respect to the papermaking fibers mainly composed of the above-mentioned wood pulp, if necessary, an adhesive, a fungicide, various papermaking fillers, a wet paper strengthening agent, Add dry paper strengthening agent, sizing agent, colorant, fixing agent, yield improving agent, slime control agent, etc., and then add known / existing Fourdrinier paper machine, cylinder paper machine, shortdrinier paper machine, Fourdrinier It can be obtained by making paper using a combination machine of a cylinder net. In addition, when adding these chemicals, it is necessary to be very careful not to mix insects and dust.

 When the beating of the wood pulp is promoted during the production of the wood pulp of the present invention, the effect of increasing the paper interlaminar strength can be expected. However, if the fine fibers in the wood pulp increase as the beating proceeds, paper dust may be generated during use as an interleaving paper, so it is not preferable to advance the beating degree more than necessary. Therefore, in the present invention, the preferable beating degree is 300 to 650 mlc. s. f. Is.

  The thickness of the handmade paper is preferably 0.01 to 2 mm, more preferably 0.05 to 1 mm, and even more preferably 0.1 to 0.5 mm.

The basis weight of the handsheets is preferably 20 to 80 g / ^{m 2,} more preferably from 25~70g / ^{m 2,} and still more preferably from a 30 to 60 g / ^{m 2.}

  The wood pulp of the present invention can be used to obtain a glass sheet interleaving paper, in particular, the glass sheet interleaving paper of the present invention, by a conventional method. Note that processing such as calendering, super calendering, soft nip calendering, embossing and the like may be performed during and / or after the papermaking of the glass sheet interleaving paper. The surface treatment and the thickness can be adjusted by the processing.

  The thickness of the glass interleaving paper is preferably 0.01 to 2 mm, more preferably 0.05 to 1 mm, and even more preferably 0.1 to 0.5 mm.

The basis weight of the glass plate for inserting paper of the present invention is preferably 20 to 80 g / ^{m 2,} more preferably from 25~70g / ^{m 2,} still to be 30 to 60 g / ^{m 2} from preferable.

The interleaving paper for glass plates of the present invention has a ratio of talc present on the surface of 3/100 m ² or less. As a result, in the glass sheet interleaving paper of the present invention, the number of regions having a minimum diameter of 30 μm or more of the hydrophobic substance such as silicone existing on the surface thereof can be set to, for example, 15 pieces / 1000 m ² or less.

  The interleaving paper obtained from the wood pulp of the present invention, in particular, the glass sheet interleaving paper of the present invention is used by being inserted between the glass sheets. For example, the glass plate interleaving paper is typically inserted one by one between a plurality of glass plates to form a laminated body as a whole, and the laminated body is a target for storage and transportation. Further, the glass sheet alone or the laminated body may be packaged using the interleaving paper made of the wood pulp of the present invention, particularly the glass sheet interleaving paper of the present invention.

  The glass plate is not particularly limited, but a glass plate for a flat panel display such as a plasma display panel, a liquid crystal display panel (particularly a TFT liquid crystal display panel) and an organic EL display panel is preferable. Fine electrodes, partition walls, etc. are formed on the surface of a glass plate for a flat panel display. By using the glass plate interleaving paper of the present invention, particularly the glass plate interleaving paper of the present invention, Since the transfer of a hydrophobic substance such as silicone to the glass plate is suppressed or avoided, even if a fine electrode, a partition wall, or the like is formed on the surface of the glass plate, the inconvenience caused by silicone can be suppressed or avoided. As a result, defects in the display can be suppressed or avoided.

  In particular, the size and weight of the glass plate for a flat panel display is increasing with the increase in size of the display. However, the glass plate interleaving paper comprising the wood pulp of the present invention, particularly the glass plate interleaving paper of the present invention, The surface of such a large or heavy glass plate can be well protected. In particular, the glass plate interleaving paper comprising the wood pulp of the present invention, particularly the glass plate interleaving paper of the present invention, has a very small number of interspersed hydrophobic substances such as silicone. It is possible to prevent or avoid the transfer of a hydrophobic substance such as the like to the glass plate. Therefore, the glass sheet interleaving paper comprising the wood pulp of the present invention, particularly the glass sheet interleaving paper of the present invention, can be suitably used for a glass sheet for a flat panel display which is particularly required to have cleanliness on the surface.

  Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples, but the scope of the present invention is not limited to the Examples.

[Transfer test method on glass plate (transport test)]
From the rear end of the mounting surface and the mounting surface for mounting the glass plate vertically, lay urethane foam on the glass mounting surface on the L-shaped frame made of aluminum and having an angle of 75 degrees. Insert 120 sheets of 680 mm x 880 mm x 0.7 mm glass plate and a glass sheet interleaving paper between each glass plate toward the backrest surface that extends in the vertical direction, and lean it so that it is parallel to the backrest surface and fix it to the pedestal. The belt-shaped belt was stretched over the entire circumference from the rear end to the backrest surface to fix the glass plate. The gantry set as described above was entirely covered with a packaging material in order to prevent dust and dirt from entering from the outside. After that, a truck transportation test was conducted. As the transportation test conditions, a test was carried out under a transportation distance of 1000 km (stored in an environment of 40 ° C. × 95% RH for 5 days during transportation).

[Example 1] (Production of wood pulp)
In a manufacturing apparatus for bleached softwood kraft pulp, which comprises a cooking step, a washing step, an oxygen delignification reaction step, and a multi-stage bleaching step with chlorine dioxide and hydrogen peroxide, an interface is used as a pitch control agent during the washing step. The activator “Miracle Pichicon 500” (manufactured by Narco Katayama) was used. As described above, softwood bleached kraft pulp A using a non-talc pitch control agent in the pulp manufacturing process was obtained. Using this softwood bleached kraft pulp A as a raw material, handmade paper was prepared by a method according to JIS P8222. Microscopic analysis of this handmade paper revealed that the ratio of talc present on the surface of the handmade paper was 2 pieces / 100 m ² .

[Comparative Example 1] (Production of wood pulp)
Further, a conifer bleached kraft pulp B was obtained in the same manner as in Example 1 except that the talc-based defoaming agent "MISTRON VAPOR" (manufactured by Nippon Mistron Co., Ltd.) was used as the pitch control agent. Using this softwood bleached kraft pulp B as a raw material, handmade paper was prepared by a method according to JIS P8222. When microscopic analysis was performed on this handmade paper, the ratio of talc existing on the surface of the handmade paper was 12 pieces / 100 m ² .

[Example 2] (Production of glass interleaving paper)
As a wood pulp, 100 parts by mass of bleached softwood kraft pulp A was prepared, and this was disintegrated to obtain a beating degree of 520 ml c. s. f. 0.4 parts by mass of polyacrylamide (trade name: Polystron 1250, manufactured by Arakawa Chemical Industry Co., Ltd.) as a paper-strengthening agent was added to the slurry prepared in Example 1 to prepare a 0.4% concentration pulp slurry. It was prepared. Using a Fourdrinier paper machine, a slip sheet for glass plate having a basis weight of 50 g / m ² was obtained. When microscopic analysis was performed on the glass sheet interleaving paper, the ratio of talc present on the surface of the glass interleaving paper was 1 piece / 100 m ² .

[Comparative Example 2] (Production of glass interleaving paper)
An interleaf paper for glass plates having a basis weight of 50 g / m ² was obtained in the same manner as in Example 2 except that softwood kraft pulp B was used as the wood pulp. When the glass sheet interleaving paper was subjected to a microscopic analysis, the ratio of talc present on the surface of the glass interleaving paper was 4 pieces / 100 m ² .

  When the transfer test confirmed the transfer of the glass sheet interleaving paper obtained in Example 2 and Comparative Example 2 to the glass sheet, it was confirmed that the liquid crystal panel array using the glass sheet using the interleaving paper of Example 2 was formed. No breakage of the color film was observed. On the other hand, when forming the array of the liquid crystal panel using the glass plate using the interleaving paper of Comparative Example 2, disconnection of the color film was recognized.

Claims (21)

Wood pulp for glass sheet interleaving paper,
A wood pulp for glass sheet interleaving paper in which the ratio of talc present on the surface of the handmade paper prepared by the method according to JIS P 8222 using the wood pulp is 10 pieces / 100 m ² or less.   The wood pulp for glass sheet interleaving paper according to claim 1, wherein the talc has an average particle size of 1 to 10 µm.   The wood pulp for glass sheet interleaving paper according to claim 1 or 2, wherein the talc is complexed with a hydrophobic substance.   The wood pulp for glass sheet interleaving paper according to claim 3, wherein the composite particle of the talc and the hydrophobic substance has an average particle size of 30 µm or more.   The wood pulp for glass sheet interleaving paper according to claim 3 or 4, wherein the hydrophobic substance contains silicone.   The wood pulp for glass sheet interleaving paper according to claim 5, wherein the silicone is silicone oil.   The wood pulp for glass sheet interleaving paper according to claim 6, wherein the silicone oil is dimethylpolysiloxane.   The wood pulp for glass sheet interleaving paper according to any one of claims 1 to 7, wherein the glass sheet is for a display.   The wood pulp for glass sheet interleaving paper according to claim 8, wherein the display is a TFT liquid crystal display or an organic EL display.   A glass sheet interleaving paper comprising the wood pulp for glass sheet interleaving paper according to any one of claims 1 to 9.   Use of the wood pulp according to any of claims 1 to 9 for the production of glass sheet interleaving paper. An interleaving paper for glass plates made from wood pulp,
An interleaving paper for glass plates in which the ratio of talc present on the surface is 3 pieces / 100 m ² or less.   The interleaving paper for glass plates according to claim 12, wherein the talc has an average particle size of 1 to 10 µm.   The glass sheet interleaving paper according to claim 12 or 13, wherein the talc is complexed with a hydrophobic substance.   The interleaving paper for glass plates according to claim 14, wherein the composite particle of the talc and the hydrophobic substance has an average particle size of 30 µm or more.   The interleaving paper for glass plates according to claim 14 or 15, wherein the hydrophobic substance contains silicone.   The glass sheet interleaving paper according to claim 16, wherein the silicone is silicone oil.   18. The interleaving paper for glass plates according to claim 17, wherein the silicone oil is dimethylpolysiloxane.   The glass sheet for a glass plate according to claim 12, wherein the glass plate is for a display.   20. The slip sheet for glass plate according to claim 19, wherein the display is a TFT liquid crystal display or an organic EL display.   A laminate comprising the slip sheet for glass plate according to any one of claims 12 to 20 and the glass plate.