JP6903123B2 - Insertion paper for glass plates and its manufacturing method - Google Patents

Description

The present invention provides paper for wrapping glass plates and paper for wrapping glass plates in the process of stacking, storing, and transporting a plurality of glass plates for flat panel displays such as liquid crystal displays, plasma displays, and organic electroluminescence (organic EL) displays. It relates to the paper sandwiched between the glass plates and the production of these papers.

Generally, in a storage process in which a plurality of glass plates for flat panels and displays are stacked and stored, a distribution process in which glass plates are transported by a truck or the like, the glass plates are impacted and come into contact with each other to cause scratches. In order to prevent the glass surface from being contaminated by contaminants from the outside world, a paper called interleaving paper is sandwiched between the glass plates.

Since glass plates for flat panel displays are used for high-definition displays compared to general window glass plates for buildings and window glass plates for vehicles, the glass surface contains impurities contained in the paper surface as much as possible. It is required to maintain a clean surface, and to have excellent flatness for high-speed responsiveness and widening of the viewing angle.

As the interleaving paper used for such applications, some 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 have already been proposed. For example, Patent Document 1 discloses a method of forming a fluorine coating film on the surface of a slip sheet. Further, Patent Document 2 is an interleaving paper in which a polyethylene-based resin foam sheet and a polyethylene-based resin film are bonded together, and Patent Document 3 is a paper made of pulp containing 50% by mass or more of bleached chemical pulp. Therefore, there is a glass interleaving paper containing a specific alkylene oxide adduct and water-soluble polyether-modified silicone, and Patent Document 4 specifies the amount of resin in the paper and takes into consideration the contamination of the glass surface. Each of the interleaving papers for glass plates using the raw materials is disclosed.

Japanese Unexamined Patent Publication No. 2012-188785 Japanese Unexamined Patent Publication No. 2010-242057 Japanese Unexamined Patent Publication No. 2008-208478 Japanese Unexamined Patent Publication No. 2006-44674

For example, it is known that when the surface of a glass plate is contaminated during the production of a color filter substrate in an array process, which is one of the manufacturing processes of a TFT liquid crystal display, problems such as disconnection occur. A color filter substrate is produced by forming a thin film such as a semiconductor film, an ITO film (transparent conductive film), an insulating film, or an aluminum metal film on a glass plate by sputtering, vacuum vapor deposition, or the like. This is because the circuit pattern formed from the thin film is broken or a short circuit occurs due to a defect in the insulating film. Further, in the production of a color filter substrate, a pattern is formed on a glass plate by photolithography. If a contaminant is present on the glass plate surface at the time of resist coating in this step, pinholes occur in the resist film after exposure or development. As a result, disconnection and short circuit occur. Similar problems have been confirmed in the manufacture of organic EL displays. An organic EL display is manufactured by forming thin films such as ITO anode, organic light emitting layer, and cathode on a glass substrate by sputtering, vapor deposition, printing, etc. Problems arise.

It was difficult to identify the cause of such contamination of the glass plate, but it has been found that one of the causes is a fine foreign substance that is transferred from the surface of the glass plate interleaving paper to the surface of the glass plate.

Also, one such foreign body has been found to be talc.

By the way, when sandwiching the interleaving paper for glass plates between the glass plates, if there is a difference in the physical state of the front and back surfaces of the interleaving paper, care should be taken so that the specific surface of the interleaving paper comes into contact with the surface of the glass plate. The need may arise. For example, a glass plate for a flat panel display is particularly repelled by the adhesion of even a small amount of foreign matter because fine circuits and the like are formed on the surface of the glass plate. If more foreign matter is present on one surface than on the other surface, the risk of the foreign matter being transferred to the surface of the glass plate increases. Care should be taken to bring the interleaving paper into contact with the surface of the glass plate. In this case, it is conceivable to sandwich two sheets of interleaving paper between the glass plates and face the surface of each interleaving paper with the smaller amount of foreign matter toward the glass plate, but the amount of interleaving paper used increases. , The weight of the laminate of the interleaving paper and the glass plate increases, which is not preferable in terms of handling.

An object of the present invention is to solve the above-mentioned problems caused by the difference in the state of the front and back surfaces of the interleaving paper for a glass plate. In particular, an object of the present invention is to provide a glass plate interleaving paper on which either the front or the back surface may be brought into contact with the glass plate.

Therefore, as a result of diligent studies, the present inventors reduced the amount of talc present on the surface of the glass plate interleaving paper and suppressed the difference in the abundance ratio of talc on the front and back surfaces of the interleaving paper. The present invention has been completed by finding that it is possible to provide a glass plate interleaving paper in which the difference between the front and back surfaces of the glass plate interleaving paper can be suppressed and either the front or back surface can be brought into contact with the glass plate.

The first aspect of the present invention is an interleaving paper for glass plates made from wood pulp, in which the abundance ratio of talc on one surface is 10 pieces / 100 m ² or less, and the presence of talc on one surface. This is a glass plate interleaving paper in which the difference between the ratio and the abundance ratio of talc on the other surface ^{is within 5 pieces / 100 m 2.}

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

The talc may be complexed with a hydrophobic substance. Moreover, it is preferable that the hydrophobic substance contains silicone.

The average particle size of the composite form of the talc and the hydrophobic substance is preferably 30 μm or more.

The thickness of the glass plate interleaving paper is preferably 20 to 200 μm.

The glass plate interleaving paper preferably has a surface friction coefficient average deviation (MMD) of 0.022 or less according to the KES method.

The glass plate is preferably for a display, more preferably for a TFT liquid crystal display or an organic EL display.

The second aspect of the present invention is the method for producing the interleaving paper for a glass plate.
Slurry preparation process to prepare wood pulp slurry,
A sheet forming step of forming the slurry into a sheet,
Wet paper preparation step of dehydrating the sheet to form wet paper,
At least a drying step of drying the wet paper to obtain the interleaving paper is included.
The present invention relates to a manufacturing method in which dehydration is performed from both sides of the sheet in the wet paper preparation step.

It is preferable to perform the dehydration by suction.

It is preferable that the difference between the dehydration rate of the suction on one surface of the sheet and the dehydration rate of the suction on the other surface is 10% or less of the dehydration rate of the suction on the other surface.

The manufacturing method preferably includes an additional suction step of further sucking both sides of the interleaving paper after the drying step.

The present invention also relates to a glass plate interleaving paper according to the first aspect of the present invention and a laminate with a glass plate.

The present invention also relates to a method for protecting a glass plate, which comprises a step of arranging a glass plate interleaving paper between the glass plates according to the first aspect of the present invention.

The amount of talc present on the front surface of the interleaving paper for glass plates of the present invention is small, and the difference in the abundance ratio of talc on the front and back surfaces of the interleaving paper is suppressed. The difference in the existence state of is suppressed. Therefore, either of the front and back surfaces of the glass plate interleaving paper of the present invention may be brought into contact with the glass plate. As a result, the interleaving paper for glass plates of the present invention is excellent in handleability.

In addition, the interleaving paper for glass plates is originally wound into a roll and shipped, but in the wound state, the front surface and the back surface of the interleaving paper come into contact with each other. When a large amount of talc is present, even if the surface of the interleaving paper is brought into contact with the surface of the glass plate, the talc on the back surface of the interleaving paper is transferred to the surface in the wound state, and the cleanliness of the surface is deteriorated. There is a risk.

However, the interleaving paper for glass plates of the present invention is wound in a roll shape because the transfer of talc from one surface of the interleaving paper to the other surface is suppressed even when the interleaving paper for a glass plate is wound in a roll shape. There is no need to worry about the deterioration of the cleanliness of the interleaving paper surface due to the removal.

Further, since the amount of talc present on the surface of the glass plate interleaving paper of the present invention is small, the problematic talc transfer from the interleaving paper to the glass plate can be effectively suppressed or avoided. By suppressing or avoiding the problematic transfer of talc to the glass plate in this way, it is possible to prevent circuit breakage of the color film or the like in the manufacturing process of the TFT liquid crystal display or the like.

The first aspect of the present invention is an interleaving paper for glass plates made from wood pulp, in which the abundance ratio of talc on one surface is 10 pieces / 100 m ² or less, and the presence of talc on one surface. This is a glass plate interleaving paper in which the difference between the ratio and the abundance ratio of talc on the other surface ^{is within 5 pieces / 100 m 2.}

The wood pulps that can be used in the present invention are softwood bleached kraft pulp (NBKP), hardwood bleached kraft pulp (LBKP), softwood bleached sulphite pulp (NBSP), hardwood bleached sulphite pulp (LBSP), and thermomechanical pulp (TMP). It is a single or mixed wood pulp such as. Mainly this wood pulp, and if necessary, non-wood pulp such as hemp, bamboo, straw, kenaf, 楮, sansho and cotton, modified pulp such as cationized pulp and marcelized pulp, rayon, vinylon, nylon, Synthetic fibers such as acrylic and polyester, chemical fibers, and microfibrillated pulp can be used alone or in combination. However, if the pulp contains a large amount of resin, the resin may have adverse effects such as soiling the surface of the glass plate. Therefore, chemical pulp with as little resin as possible, for example, softwood bleached kraft pulp is used alone. It is preferable to do so. Further, high-yield pulp such as crushed wood 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 sword cutting property and improves the workability when flattening the interleaving paper, but it is necessary to be careful because the recyclability deteriorates in terms of waste treatment. ..

The form of the wood pulp is not particularly limited, and any form such as a sheet, a block, or flakes can be taken. Sheet pulp can be obtained using, for example, a pulp machine having four steps of wire part, press part, dry part and finishing. In the wire part, pulp fibers are made from paper using a long net or a vacuum filter, and in the press part, they are dehydrated using a roll press. In the dry part, it is dried with a cylinder dryer, a fructo dryer, etc., and finally both ends of the sheet pulp are cut off and wound on a roll. Such a method is described in detail in the "Pulp and Paper Manufacturing Technology Series" published by the Pulp and Paper Technology Association and the "Pulp and Paper Manufacturing Technology Complete Book". The block-shaped pulp can be obtained by laminating the sheet-shaped pulp, for example, and the flake-shaped pulp can be obtained by crushing the sheet-shaped pulp, for example.

The thickness of the sheet pulp is preferably 0.7 to 1.5 mm, more preferably 0.9 to 1.3 mm, and even more preferably 1.0 to 1.2 mm. ..

The basis weight of the pulp sheet is preferably 400~1300g / ^{m 2,} more preferably from 500~1200g / ^{m 2,} more preferably from 500~1100g / ^{m 2,} 500~1000g / more preferably ^m is ^2, more preferably from a 700～1000G / ^{m 2.}

In the interleaving paper for glass plates of the present invention, the abundance ratio of talc on one surface is ^{limited to 10 pieces / 100 m 2} or less. The number of talcs present on one surface of the glass plate interleaving paper ^{is preferably 7 pieces / 100 m 2} or less, more preferably 5 pieces / 100 m ² or less, and 3 pieces / 100 m ² or less. It is even more preferably 1 piece / 100 m ² or less, even more preferably 0.8 pieces / 100 m ² or less, and particularly preferably 0.5 piece / 100 m ² or less. preferable.

In the interleaving paper for glass plates of the present invention, the difference between the abundance ratio of talc on one surface and the abundance ratio of talc on the other surface is ^{within 5 pieces / 100 m 2 and} within 4 pieces / 100 m ² . It is preferably 3 pieces / 100 m ^{2 or} less, more preferably 2 pieces / 100 m ^{2 or} less, and even more preferably 1 piece / 100 m ^{2 or} less. That is, in the interleaving paper for glass plates of the present invention, it is preferable that the ratio of talc on one surface does not fluctuate significantly from the ratio of talc present on the other surface to the extent that it falls within the above specific range. Here, the "presence ratio" means the number of talc per unit area on the surface of the interleaving paper. For example, a plurality of locations on the surface of the interleaving paper for glass plates are magnified and observed with an electron microscope, and the locations are concerned. It can be determined by averaging the number of talcs observed in. Alternatively, as another method, the abundance ratio of talc can be determined by sufficiently washing the surface of a predetermined area of the glass plate interleaving paper with water or an acidic solution such as concentrated sulfuric acid and counting the talc that has fallen off.

In the interleaving paper for glass plates of the present invention, the amount of talc present on the front surface is small, and fluctuations in the abundance ratio of talc on the front and back surfaces of the interleaving paper are suppressed. Differences in physical condition between the front and back surfaces are suppressed. Therefore, in the interleaving paper for glass plates of the present invention, the abundance ratio of talc on the front surface does not differ significantly between the front and back surfaces of the interleaving paper. Therefore, in the interleaving paper for a glass plate of the present invention, either the front or the back surface may be brought into contact with the glass plate.

The talc in the present invention is not particularly limited. Talc is called "hydrous magnesium silicate", the formula can be represented in _{4SiO 2 · 3MgO · H 2 O} . The chemical composition is slightly different depending on the production area, and the theoretical values are _{the weight ratios of SiO 2} 64.4%, MgO 31.8%, and ignition loss (moisture) 4.7%. Talc is also called talc.

The average particle size 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 size may be a volume average particle size, and can be measured by, for example, 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, and 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. Even more preferably ml or less, and even more preferably 0.2 g / ml or less.

The surface of talc is relatively lipophilic, and it can be combined with a hydrophobic substance by adsorbing a hydrophobic substance such as silicone. Talc can adsorb hydrophobic substances such as silicone even in water. In the present invention, talc may be compounded with a hydrophobic substance. The form of the composite of talc and the hydrophobic substance, particularly silicone, is not particularly limited, but at least a part of the talc may be coated with the hydrophobic substance, or at least a part of the talc is a hydrophobic substance. It may have penetrated.

The average particle size of the composite form of the talc and the hydrophobic substance is preferably 30 μm or more, more preferably 40 μm or more, and even more preferably 50 μm or more.

The hydrophobic substance is not particularly limited. Hydrophobic substances are preferably non-volatile and are oils (excluding silicone oils, such as aliphatic hydrocarbons, vegetable oils, animal oils, synthetic glycerides, aliphatic alcohols, fatty acids, aliphatic alcohols and / or esters of fatty acids). , Resins (excluding silicones), silicones, pitches, rubbers, and mixtures thereof are more preferred, and silicones are even more preferred.

Aliphatic hydrocarbons include, for example, linear or branched hydrocarbons, particularly mineral oil (liquid paraffin, etc.), paraffin, petrolatum, that is, petrolatum, naphthalene, etc .; hydrogenated polyisobutene, isoeikosan, polydecene, pearl dream, etc. Hydrocarbonated polyisobutene and decene / butene copolymers; and mixtures thereof can be mentioned.

Examples of other aliphatic hydrocarbons may include linear, branched, or optionally cyclic, C _{6 to} C ₁₆ lower alkanes. Examples that can be mentioned include hexane, undecane, dodecane, tridecane and isoparaffin, such as isohexadecane and isodecane.

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

Examples of animal oils include mink oil, squalene, perhydrosqualene and squalene.

Examples of synthetic glycerides include caprylic acid / capric acid triglycerides.

Fatty acids should be in acidic form (ie, not in salt form to avoid soaping) and may be saturated or unsaturated, with 6-30 carbon atoms, especially 9-30 carbons. It contains atoms and is optionally substituted with one or more hydroxyl groups (particularly 1 to 4). If the fatty acid is unsaturated, the compound can contain 1-3 conjugated or unconjugated carbon-carbon double bonds. The fatty acid is selected from, for example, 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, it is replaced with 1 to 4).

Of the aliphatic alcohols, C _{12 to} C ₂₂ aliphatic alcohols are preferable, and C _{16 to} C ₁₈ saturated aliphatic alcohols are more preferable. 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 fatty alcohols are saturated or unsaturated, linear or branched C _1-2 C ₂₆ aliphatic monoacid or polyacid esters, and saturated or unsaturated, linear. Esters of cyclic or branched C _{1 to} C ₂₆ fatty monovalent alcohols or polyhydric alcohols can be particularly mentioned, and the total carbon number of the ester is 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, polysell, polycarbonate, polyamide, and polyimide, polyurethane, melamine resin, and urea resin. Examples thereof include thermosetting resins such as, and mixtures thereof.

Examples of silicone include silicone oil. The 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 the silicone oil include linear organopolysiloxane, cyclic organopolysiloxane, and branched organopolysiloxane.

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 linear organopolysiloxane, the cyclic organopolysiloxane, and the branched organopolysiloxane include 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)

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

The substituted or unsubstituted monovalent hydrocarbon group is typically one of substituted or unsubstituted, having 1 to 30 carbon atoms, preferably 1 to 10 carbon atoms, and more preferably 1 to 4 carbon atoms. Valuable saturated hydrocarbon group; 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 a number of 6 to 30, more preferably 6 to 12 carbon atoms.

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

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

Examples of the monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms include aryl groups such as a phenyl group, a tolyl group, a xsilyl group, and a mesityl group. A phenyl group is preferred. In the present specification, the aromatic hydrocarbon group includes not only a group consisting only of aromatic hydrocarbons but also a group in which an aromatic hydrocarbon and an aliphatic saturated hydrocarbon are combined. Examples of a 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 monovalent hydrocarbon group may be substituted with one or more substituents, which are, for example, halogen atoms (fluorine atom, chlorine atom, bromine atom and iodine atom), hydroxyl group. , Carbinol group, epoxy group, glycidyl group, acyl group, carboxyl group, amino group, methacryl group, mercapto group, amide group, oxyalkylene group and the like are selected from the group consisting of organic groups. Specifically, 3,3,3-trifluoropropyl group, 3-chloropropyl group, 3-hydroxypropyl group, 3- (2-hydroxyethoxy) propyl group, 3-carboxypropyl group, 10-carboxydecyl group. , 3-Isocyanate propyl group and the like.

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

More specifically, as the linear organopolysiloxane, dimethylpolysiloxane having a trimethylsiloxy group-blocking trimethylsiloxy group at both ends of the 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 ends of the molecular chain, trimethylsiloxy group-blocked dimethylsiloxane / methylphenylsiloxane copolymer at both ends of the molecular chain, trimethylsiloxy group-blocked diphenylpolysiloxane at both ends of the molecular chain , Molecular chain double-ended trimethylsiloxy group-blocked dimethylsiloxane / diphenylsiloxane copolymer, trimethylpentaphenyltrisiloxane, phenyl (trimethylsiloxy) siloxane, molecular chain double-ended trimethylsiloxy group-blocked methylalkylpolysiloxane, molecular chain double-ended trimethylsiloxy Group-blocked dimethylpolysiloxane / methylalkylsiloxane copolymer, molecular chain double-ended trimethylsiloxy group-blocked dimethylsiloxane / methyl (3,3,3-trifluoropropyl) siloxane copolymer, α, ω-dihydroxypolydimethylsiloxane, α, ω-diethoxypolydimethylsiloxane, 1,1,1,3,5,5,5-heptamethyl-3-octyltrisiloxane, 1,1,1,3,5,5,5-heptamethyl-3-3 Dodecyltrisiloxane, 1,1,1,3,5,5,5-heptamethyl-3-hexadecyltrisiloxane, tristrimethylsiloxymethylsilane, tristrimethylsiloxyalkylsilane, tetraxtrimethylsiloxysilane, tetramethyl-1,3 Examples thereof include −dihydroxydisiloxane, octamethyl-1,7-dihydroxytetrasiloxane, hexamethyl-1,5-diethoxytrisiloxane, hexamethyldisiloxane, octamethyltrisiloxane, higher alkoxy-modified silicone, higher fatty acid-modified silicone, and dimethiconol. Will be done.

Cyclic organopolysiloxanes include hexamethylcyclotrisiloxane (D3), octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), dodecamethylcyclohexasiloxane (D6), and 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-methacryloxypropyl) ) 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, 1,3,5,7 -Tetra [3- (p-vinylphenyl) propyl] tetramethylcyclotetrasiloxane, 1,3,5,7-tetra (N-acryloyl-N-methyl-3-aminopropyl) tetramethylcyclotetrasiloxane, 1, Examples thereof include 3,5,7-tetra (N, N-bis (lauroyl) -3-aminopropyl) tetramethylcyclotetrasiloxane.

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. Dimethylpolysiloxane 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 to the molecule via a silicon-carbon bond, and is preferably water-soluble at room temperature, specifically at 25 ° C. It is more preferably nonionic.

Specifically, the polyoxyalkylene-modified silicone oil is a copolymer of a silicone oil composed of, for example, a linear or branched siloxane and a polyoxyalkylene, and there are various types, and in particular, the following formula (4). ) Is preferable.

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

(During the ceremony,
R ¹ is the same as above, independently of each other.
R ² is independently R ¹ or A, respectively.
A is ^{a group independently represented by R 3} G, R ³ is a substituted or unsubstituted divalent hydrocarbon group, and G is an ethylene oxide, propylene oxide, etc. having 2 to 5 carbon atoms. Represents a polyoxyalkylene group containing at least one alkylene oxide of
d represents an integer from 1 to 500 and represents
e represents an integer from 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 specifically, a methylene group, a dimethylene group and a trimethylene group. A linear or branched alkylene group having 1 to 30 carbon atoms such as a group, tetramethylene group, pentamethylene group, hexamethylene group, heptamethylene group, octamethylene group; vinylene group, allylene 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; alkylene arylene group having 7 to 30 carbon atoms such as dimethylenephenylene group ; And the hydrogen atom bonded to the carbon atom of these groups is at least partially a halogen atom such as fluorine, a hydroxyl group, or a carbinol group, an epoxy group, a glycidyl group, an acyl group, a carboxyl group, an amino group, or a methacryl group. , A group substituted with an organic group including a mercapto group, an amide group, an oxyalkylene group and 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であり、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, specific examples of the polyoxyalkylene-modified silicone oil include the following.

(During the ceremony,
x is 20 to 160, y is 1 to 25, and the value of x / y is 50 to 2.
A is, for example, − (CH ₂ ) ₃ O − (CH ₂ CH ₂ O) _m − (CH ₂ CH ₂ CH ₂ O) _n −R ⁴ , m is 7 to 40, n is 0 to 40, m + n. The value of is at least 1, and it may be graft-polymerized or randomly polymerized, and R ⁴ represents a hydrogen atom or the above-mentioned substituted or unsubstituted monovalent hydrocarbon group. Preferably, m is 7 to 30 and n is 0 to 30).

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

The aminoalkyl-modified silicone oil is a silicone oil in which an aminoalkyl group is bonded in the molecule via a silicon-carbon bond, and preferably exhibits a viscosity of 10 to 100,000 cs at room temperature, specifically at 25 ° C. Is.

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

In the interleaving paper for glass plates of the present invention, the content of silicone contained in the interleaving paper is preferably limited to 0.5 ppm or less based on the absolute dry mass of the interleaving paper, and 0.4 ppm or less is more preferable. Preferably, 0.3 ppm or less is more preferable, 0.2 ppm or less is even more preferable, and 0.1 ppm or less is particularly preferable.

On the other hand, in the interleaving paper for glass plates of the present invention, silicone may be present as long as it is an extremely small amount that does not cause a problem, and therefore the content of silicone does not have to be zero. For example, the silicone content may be 0.1 ppb.

The silicone content is based on the absolute dry mass of the interleaving paper. In the present invention, "absolute drying" means a state in which moisture is substantially not present in the object to be dried due to drying.

The silicone content can be determined, for example, by subjecting the interleaving paper to an extraction step in an organic solvent capable of extracting silicone and quantifying the amount of extracted silicone.

In the interleaving paper for glass plates of the present invention, the difference between the number of silicone-containing discontinuous regions having a diameter of 30 μm or more on one surface and the number of silicone-containing discontinuous regions having a diameter of 30 μm or more on the other surface is 5 / It is preferably 1000 m ^{2 or} less, 4 pieces / 1000 m ^{2 or} less, 3 pieces / 1000 m ^{2 or} less, 2 pieces / 1000 m ^{2 or} less, and 1 piece / 1 piece / Even more preferably, it is within 1000 m ^2. That is, in the interleaving paper for glass plates of the present invention, the abundance of the silicone-containing discontinuous region on one surface does not fluctuate significantly from the abundance of the discontinuous region on the other surface to the extent that it falls within the above specific range. Is preferable. Here, the "absence amount" means the number of the silicone-containing discontinuous regions per unit area of the surface of the interleaving paper, and for example, a plurality of locations on the surface of the interleaving paper for a glass plate are enlarged by an electron microscope. It can be determined by observing and averaging the number of silicone-containing discontinuities observed at the site per unit area.

The shape of the silicone-containing discontinuous region in the present invention is arbitrary, and may be various shapes such as a circle, an ellipse, and a square, but a circle or an ellipse is preferable. Specifically, the discontinuous regions can be scattered in the form of dots or spots.

In the present invention, the "diameter" of the discontinuous region means the area equivalent circle diameter (diameter of a circle having an area equal to the area of the discontinuous region). The diameter of the discontinuous region is preferably 25 μm or more, more preferably 20 μm or more, further preferably 15 μm or more, further preferably 10 μm or more, further preferably 5 μm or more, further preferably 1 μm or more, and even more preferably 0.5 μm or more. Is particularly preferable. When the discontinuous region is circular, its diameter is the "diameter". When the discontinuous region is non-circular, the area equivalent circle diameter (diameter of a circle having an area equal to the area of the discontinuous region) is preferably 25 μm or more, preferably 20 μm or more, and more preferably 15 μm or more. 10 μm or more is even more preferable, 5 μm or more is even more preferable, 1 μm or more is even more preferable, and 0.55 μm or more is particularly preferable. The diameter and area of the discontinuous region can be measured, for example, by microscopy.

The diameter of the discontinuous region is preferably 10 mm or less, more preferably 5 mm or less, further preferably 3 mm or less, further preferably 1 mm or less, further preferably 500 μm or less, further preferably 100 μm or less, and particularly preferably 50 μm or less. preferable. When the discontinuous region is circular, its diameter is preferably 10 mm or less, more preferably 5 mm or less, further preferably 3 mm or less, further preferably 1 mm or less, and even more preferably 500 μm or less. , 100 μm or less is even more preferable, and 50 μm or less is particularly preferable. When the discontinuous region is non-circular, the area equivalent circle diameter is preferably 10 mm or less, preferably 5 mm or less, more preferably 3 mm or less, further preferably 1 mm or less, further preferably 500 μm or less, and even more preferably 100 μm. The following is even more preferable, and 50 μm or less is particularly preferable.

It is preferable that there is no silicone-containing discontinuous region having a diameter of more than 10 mm on the surface of the interleaving paper for a glass plate of the present invention.

In the above case, the silicone-containing discontinuous region on the surface of the interleaving paper is, for example, colored (typically hydrophobic) having an affinity for silicone on the surface of the interleaving paper but not for the interleaving paper. An agent or color former is applied and the colored or colored area on the surface is measured, or the surface of the interleaving paper has an affinity for the interleaving paper but not silicone (typically). Can be determined by applying a (hydrophilic) colorant or color former and measuring the non-colored or non-colored area on the surface.

In the interleaving paper for glass plates of the present invention, the content of silicone contained in the interleaving paper is limited to 0.5 ppm or less based on the weight of the interleaving paper, and the diameter on one surface is 30 μm or more. When the difference between the number of silicone-containing discontinuous regions on the other surface and the number of silicone-containing discontinuous regions having a diameter of 30 μm or more on the other surface is 5 pieces / 1000 m ^{2 or} less, the interleaving paper for glass plates of the present invention also applies to silicone. The content is small, and the fluctuation of the abundance of the silicone-containing discontinuous region on the front and back surfaces of the interleaving paper is suppressed, so that the difference in the physical state of the silicone on the front and back surfaces of the interleaving paper for glass plates is suppressed. Is also suppressed. Therefore, in the above case, it is possible to reduce the possibility that the talc is compounded with silicone to become a silicone-containing foreign substance, and even if a silicone-containing foreign substance is generated, the abundance thereof is small, and the front of the interleaving paper. The abundance ratio does not differ significantly on the back surface. Therefore, also in the above case, the glass plate interleaving paper of the present invention may be in contact with either the front or back surface of the interleaving paper.

The thickness of the interleaving paper for a glass plate of the present invention is preferably 20 to 200 μm, more preferably 30 to 150 μm, and even more preferably 40 to 200 μm. As described above, by using a relatively thin interleaving paper, it is possible to further suppress the difference in the physical state of the front and back surfaces of the interleaving paper.

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.

In the glass plate interleaving paper of the present invention, the average deviation (MMD) of the friction coefficient of the surface by the KES method is preferably 0.022 or less, preferably 0.020 or less, and 0.019 or less. More preferably, it is even more preferably 0.018 or less, and even more preferably 0.017 or less. MMD uses a friction tester (KES-SE manufactured by Kato Tech Co., Ltd.) to fix a 10 mm square friction element consisting of a bundle of piano wires with a diameter of 0.5 mm on the surface of paper fixed with a tension of 20 g / cm. It is an average deviation value of the friction coefficient measured by moving the sample by 2 cm at a sample moving speed of 0.1 cm / sec in the same direction as the tension is applied while making contact with the sample at a contact pressure of 50 g / cm ^2. When this MMD is large, it means that the coefficient of friction of the paper surface fluctuates greatly depending on the position of the paper surface, and microscopically, it means that the minute irregularities on the surfaces of the papers increase. By providing fine irregularities on the surface of the interleaving paper in this way, the coefficient of friction between the surface of the glass plate and the surface of the interleaving paper becomes small, and the removal work when removing the interleaving paper from the surface of the glass plate becomes easy. .. If the MMD exceeds 0.022, minute irregularities on the surfaces of the papers increase, and the catching between the papers increases, which is not preferable. The MMD is, for example, preferably 0.001 to 0.022, more preferably 0.002 to 0.020, and even more preferably 0.004 to 0.019.

The interleaving paper for glass plates of the present invention may contain short fibers having a fiber length of 200 μm or less, but since the short fibers may attract foreign substances, the content of the short fibers is the absolute dry weight of the interleaving paper. On the other hand, it is preferably 10.5% by weight or less, more preferably 10.0% by weight or less, even more preferably 9.5% by weight or less, and particularly preferably 9.0% by weight or less. Here, "fiber length" does not mean the average fiber length. Therefore, all short fibers having a fiber length of 200 μm or less have a fiber length of 200 μm or less. In other words, the maximum fiber length of the short fibers is 200 μm or less. Here, the fiber length refers to the length of the fiber when the fiber is in a straight stretched state.

The average fiber diameter of the short fibers is preferably 10 μm to 50 μm, more preferably 12 μm to 40 μm, and even more preferably 15 μm to 30 μm.
The "average fiber diameter" here means that a predetermined number of fibers are randomly selected from each electron microscope image by magnifying and observing a plurality of locations on the surface of the glass plate interleaving paper with an electron microscope. It means the average fiber diameter obtained by measuring and averaging the diameter of the fiber. The number of fibers to be selected is 100 or more, preferably 150 or more, more preferably 200 or more, and even more preferably 300 or more.

Abundance of the short fibers in the surface of the slip sheet glass plate of the present invention is preferably from 300 lines to 850 present / cm ^2, more preferably is 330 present 800 present / cm ^2, 350 present - More preferably, it is 750 lines / cm ^2. When the abundance of the short fibers is relatively small, the amount of foreign matter attracted by the short fibers can be reduced.

In the interleaving paper for glass plates of the present invention, the difference between the abundance of the short fibers on one surface and the abundance of the short fibers on the other surface is 15% of the abundance of the short fibers on the other surface. It is preferably less than or equal to, more preferably 12% or less, and even more preferably 10% or less. That is, in the interleaving paper for glass plates of the present invention, it is preferable that the abundance of short fibers on one surface does not fluctuate significantly from the abundance of short fibers on the other surface to the extent that it falls within the above specific range. Here, the "absence amount" means the number of the short fibers per unit area of the surface of the interleaving paper. For example, a plurality of locations on the surface of the interleaving paper for a glass plate are magnified and observed with an electron microscope. It can be determined by averaging the number of short fibers observed at the site per unit area. It can also be determined by obtaining the number of short fibers of 200 μm or less per unit area from the fibers that have fallen by rubbing a predetermined area with a sheet or the like with the surface of the interleaving paper facing downward. Further, it can also be determined by dividing the interleaving paper into two sheets in the center in the thickness direction to form two very thin sheets, slurry each paper, and measure the number of short fibers of 200 μm or less in the slurry. Alternatively, as another method, the abundance of short fibers can be determined by sufficiently washing the surface of the glass plate interleaving paper with water and subjecting the fallen fibers to a fiber length measuring machine.

The interleaving paper for a glass plate of the present invention can be produced based on a usual method such as a papermaking method.

A second aspect of the present invention is a method for producing a slip sheet for a glass plate.
Slurry preparation process to prepare wood pulp slurry,
A sheet forming step of forming the slurry into a sheet,
Wet paper preparation step of dehydrating the sheet to form wet paper,
At least a drying step of drying the wet paper to obtain the interleaving paper is included.
This is a manufacturing method in which dehydration is performed from both sides of the sheet-like slurry in the wet paper preparation step.

In the slurry preparation step, a slurry of wood pulp can be prepared by a conventionally known method. For example, in the slurry preparation step, the cellulose fibers constituting the wood pulp are dissociated into an aqueous suspension to prepare a slurry.

Further, as long as the performance of the present invention is not impaired, an adhesive, a fungicide, a defoaming agent, a filler, a wet paper strength enhancer, a dry paper strength enhancer, a sizing agent, etc. Coloring agents, fixing agents, yield improving agents, slime control agents and the like can be added. When adding these chemicals, it is preferable to take great care not to mix insects and dust.

In general, talc is often contained in wood pulp and interleaving paper. This is because talc is often used as a pitch control agent in the manufacturing process of wood pulp and interleaving paper. 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 improving printing characteristics.

In the second aspect of the present invention, a non-talc pitch control agent, filler, pigment or the like is used in order to reduce the abundance ratio of talc on one surface of the obtained interleaving paper to 10 pieces / 100 m ^{2 or less.} Can be done.

In general, wood pulp and interleaving paper often contain silicone. This is because a silicone-based defoaming agent is often used as a defoaming agent used to prevent a decrease in cleaning ability due to the generation of foam in the manufacturing process of wood pulp and interleaving paper, especially in the cleaning process. Silicone derived from defoamer remains on pulp and interleaving paper. The silicone-based defoaming 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, when reducing the content of silicone contained in the interleaving paper for glass plates to 0.5 ppm or less, it is preferable to use a non-silicone defoaming agent as the defoaming agent when using the defoaming agent. Further, it is preferable to use wood pulp obtained by using a non-silicone antifoaming agent.

When the slurry is prepared, the effect of increasing the paper interlayer strength can be expected by advancing the beating of the wood pulp. However, if the number of fine fibers increases as the beating progresses, there is a risk of causing inconveniences such as attracting foreign substances and generating paper dust during use as interleaving paper, so it is not preferable to advance the beating degree more than necessary. .. The preferred beating degree in the present invention is 300 to 650 mlc. s. f. Is.

In the sheet forming step of forming the slurry into a sheet, the slurry can be formed into a sheet by a conventionally known method. For example, by discharging the slurry onto a flat wire (for example, a long net paper machine), or by scooping a sheet from the slurry with a wire wound around a cylindrical cylinder (for example, a circular net paper machine). , You can get the sheet.

In the second aspect of the present invention, dehydration is performed from both sides of the sheet in the wet paper preparation step of dehydrating the sheet to form a wet paper. As a result, the talc contained in the sheet is effectively removed from both sides of the sheet. The difference between the abundance ratio of talc on one surface of the glass plate interleaving paper obtained by the second aspect of the present invention and the abundance ratio of talc on the other surface shall be within ^{5 pieces / 100 m 2.} Can be done.

Further, by performing dehydration from both sides of the sheet in the wet paper preparation step of dehydrating the sheet to form a wet paper, the silicone-containing foreign matter contained in the sheet can be effectively removed from both sides of the sheet. Therefore, the number of silicone-containing discontinuous regions having a diameter of 30 μm or more on one surface of the glass plate interleaving paper obtained by the second aspect of the present invention and the silicone-containing discontinuous regions having a diameter of 30 μm or more on the other surface. The difference from the number can be within ^{5 pieces / 1000 m 2.}

The dehydration method is arbitrary, and a conventionally known method can be used. For example, the sheet can be dehydrated by pressing it with a roll. However, for effective removal of talc, it is preferable to carry out the dehydration by suction.

In the step of dehydrating from both sides of the sheet, for example, the sheet extending in the horizontally direction may be sandwiched between the top and bottom by a net and sucked in the vertical direction by a suction device to dehydrate. Since there is a difference between the suction force to and the downward suction force, more talc may remain on the sheet surface on the upward suction side than on the sheet surface on the downward suction side. It is preferable to sandwich a sheet extending in the vertical direction with a net and suck it in the left-right direction to dehydrate it. In this case, it is preferable to maintain the wet paper so that the moving direction is the vertical direction or an inclination range within 30 ° from the vertical direction.

It is preferable that the difference between the dehydration rate of the suction on one surface of the sheet and the dehydration rate of the suction on the other surface is 10% or less of the dehydration rate of the suction on the other surface. That is, in the method for producing the interleaving paper for a glass plate of the present invention, it is preferable that suction from both sides of the sheet is performed with substantially the same suction force.

The sheet forming step and the wet paper preparation step may be carried out individually using separate devices, but may be carried out continuously or partially overlapping in the same device. For example, in the wire part of a paper machine, the slurry may be placed on a wire (net) to form a sheet and dehydrated to form a wet paper.

In the drying step, the wet paper can be dried to obtain the interleaving paper by a conventionally known method using a dryer roll or the like.

In order to further remove talc that may remain on the surface of the interleaving paper, the method for producing the interleaving paper for a glass plate of the present invention preferably includes an additional suction step of further sucking both sides of the interleaving paper after the drying step. ..

In addition, processing such as calender processing, super calender processing, soft nip calender processing, embossing, etc. may be performed during and / or after papermaking of the interleaving paper for glass plate. The surface properties and thickness can be adjusted by processing.

According to the production method of the second aspect of the present invention, the interleaving paper for a glass plate of the first aspect of the present invention can be efficiently produced.

The interleaving paper for glass plates of the present invention is used by being inserted between the glass plates. For example, the interleaving paper for glass plates 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 plate alone or the laminate may be wrapped using the glass plate interleaving paper of the present invention. Therefore, the present invention has an aspect of a method for protecting a glass plate, which includes a step of arranging (particularly inserting) the interleaving paper for the glass plate between the glass plates.

The glass plate is not particularly limited, but is preferably 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. Fine electrodes, partition walls, etc. are formed on the surface of the glass plate for flat panel display, but by using the interleaving paper for glass plate of the present invention, the transfer of fine foreign matter to the glass plate becomes a problem. Is suppressed or avoided, so even if fine electrodes, partition walls, etc. are formed on the surface of the glass plate, inconvenience caused by the foreign matter can be suppressed or avoided, and as a result, defects in the display are suppressed or avoided. be able to.

In particular, the size and weight of glass plates for flat panel displays are increasing with the increase in size of displays, and the interleaving paper for glass plates of the present invention covers the surface of such large to heavy glass plates. Can be well protected. In particular, since the interleaving paper for a glass plate of the present invention contains an extremely small amount of talc-based foreign matter, it is possible to suppress or avoid the transfer of the foreign matter to the glass plate even when pressed by a heavy glass plate. Therefore, the interleaving paper for a glass plate of the present invention can be suitably used for a glass plate for a flat panel display in which surface cleanliness is particularly required.

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

[Measurement of talc]
The slip sheet glass plate was cut into 1 m ^2, washed thoroughly one side of the paper with de metal ion water. The aqueous solution after washing was recovered and filtered through a polycarbonate membrane filter (MILLIPORE, pore size 0.8 μm) to obtain a residue. This residue was observed using an electron microscope, and the number of talc on the surface of the glass interleaving paper was measured by EDS analysis of a foreign substance having a particle size of 1 μm or more.

[Transfer test method to glass plate (transportation test)]
Urethane foam is laid on the glass mounting surface on the L-shaped stand that is made of aluminum and has an angle of 75 degrees, and from the mounting surface for vertically mounting the glass plate and the rear end of the mounting surface. Insert a glass plate interleaving paper between 120 glass plates of size 680 mm x 880 mm x 0.7 mm and each glass plate toward the backrest surface extending in the vertical direction, and lean against the backrest surface so that it is parallel to the backrest surface. A fixed strip-shaped belt was hung from the rear end to the backrest surface over the entire circumference to fix the glass plate. The entire surface of the gantry set as described above was 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 for the transportation test conditions, the test was carried out at a transportation distance of 1000 km (stored in an environment of 40 ° C. × 95% RH for 5 days during transportation).

[Example 1]
It is not used as a pitch control agent in the coniferous bleached kraft pulp manufacturing apparatus, which consists of a cooking step, a washing step, an oxygen delignin reaction step, and a multi-stage bleaching bleaching step using chlorine dioxide and hydrogen peroxide. A talc-based surfactant "Miracle Pichicon 500" (manufactured by Narco Katayama) was used. In this way, softwood bleached kraft pulp using a non-talc surfactant during the manufacturing process was obtained. 100 parts by mass of this was prepared, and this was dissociated to give a beating degree of 550 mlc. s. f. Polyacrylamide (trade name: Polystron 1250, manufactured by Arakawa Chemical Industry Co., Ltd.) was added as a paper strength enhancer to the pulp prepared in 1. Was tuned. This was made using a long net paper machine equipped with an on-top former in the wire part, and dehydrated from both sides of the wet paper by the on-top former to obtain a glass plate interleaving paper with ^{a basis weight of 55 g / m 2.} ..

[Comparative Example 1]
A glass plate interleaving paper having a ^{basis weight of 55 g / m 2} was obtained by the same method as in Example 1 except that the on-top former was not used.

[Comparative Example 2]
Further, a glass plate interleaving paper having ^{a basis weight of 55 g / m 2} was obtained by the same method as in Example 1 except that the talc-based pitch control agent "MISRON VAPOR" (manufactured by Nippon Mistron Co., Ltd.) was used as the surfactant. ..

When the abundance ratio of talc on the surface of the interleaving paper for glass plates of Examples and Comparative Examples was determined, one surface of Example 1 was 7 pieces / 100 m ² , and the other side was 11 pieces / 100 m ² . there were. In Comparative Example 1, the surface was 7 pieces / 100 m ² and the other surface was 17 pieces / 100 m ² . In Comparative Example 2, one surface had 87 pieces / 100 m ² and the other side had 153 pieces / 100 m ² . Further, when the transfer of the glass plate interleaving paper obtained in Examples and Comparative Examples to the glass plate was confirmed by a transport test, an array of liquid crystal panels was formed using the glass plate using the interleaving paper of Example 1. At that time, no disconnection of the color film was observed. On the other hand, when the liquid crystal panel array was formed using the glass plates using the glass plate interleaving papers of Comparative Examples 1 and 2, disconnection of the color film was observed.

Claims (15)

It is a glass plate interleaving paper made from wood pulp.
The abundance ratio of talc on one surface is 10 pieces / 100 m ² or less.
A glass plate interleaving paper in which the difference between the abundance ratio of talc on one surface and the abundance ratio of talc on the other surface ^{is within 5 pieces / 100 m 2.} The interleaving paper for a glass plate according to claim 1, wherein the average particle size of the talc is 1 to 10 μm. The interleaving paper for a glass plate according to claim 1 or 2, wherein the talc is compounded with a hydrophobic substance. The interleaving paper for a glass plate according to claim 3, wherein the average particle size of the composite form of the talc and the hydrophobic substance is 30 μm or more. The interleaving paper for a glass plate according to claim 4, wherein the hydrophobic substance contains silicone. The interleaving paper for a glass plate according to any one of claims 1 to 5, which has a thickness of 20 to 200 μm. The interleaving paper for a glass plate according to any one of claims 1 to 6, wherein the mean deviation (MMD) of the friction coefficient of the surface by the KES method is 0.022 or less. The interleaving paper for a glass plate according to any one of claims 1 to 7, wherein the glass plate is for a display. The interleaving paper for a glass plate according to claim 8, wherein the display is a TFT liquid crystal display or an organic EL display. A laminate made of the interleaving paper for a glass plate and the glass plate according to any one of claims 1 to 9. A method for protecting a glass plate, which comprises a step of arranging the interleaving paper for the glass plate according to any one of claims 1 to 9 between the glass plates. The method for manufacturing a glass plate interleaving paper according to any one of claims 1 to 9.
Slurry preparation process to prepare wood pulp slurry,
A sheet forming step of forming the slurry into a sheet,
Wet paper preparation step of dehydrating the sheet to form wet paper,
At least a drying step of drying the wet paper to obtain the interleaving paper is included.
A manufacturing method in which dehydration is performed from both sides of the sheet in the wet paper preparation step. The manufacturing method according to claim 12, wherein the dehydration is performed by suction. 13. The production method according to claim 13, wherein the difference between the dehydration rate of the suction on one surface of the sheet and the dehydration rate of the suction on the other surface is 10% or less of the dehydration rate of the suction on the other surface. .. The manufacturing method according to claim 13 or 14, further comprising an additional suction step of sucking both sides of the interleaving paper after the drying step.