JP5019953B2 - Release paper, paper adhesive tape and method for producing release paper - Google Patents

Description

  The present invention relates to a release paper, a paper adhesive tape, and a method for producing a release paper. More specifically, the present invention relates to a release paper that can be used mainly for a paper adhesive tape or the like used for packing a packaging container, a manufacturing method thereof, and a paper adhesive tape using the release paper.

Conventionally, a paper adhesive tape such as a kraft adhesive tape is used for packing a packaging container. These paper adhesive tapes are commercially available in a state of being wound in a cylindrical shape, and are used for packing packaging containers by pulling out a necessary length.
When pulling out a paper adhesive tape from a paper adhesive tape wound in a cylindrical shape, it is required to easily peel from the surface of the paper substrate to which the adhesive layer of the cylindrical paper adhesive tape is in close contact For this reason, the surface of the paper base material to which the pressure-sensitive adhesive layer of the cylindrically wound paper pressure-sensitive adhesive tape is in close contact is provided with peelability.

In order to give the paper substrate surface of the paper adhesive tape a peelable property, a release layer can be formed by applying a solution prepared by dissolving a release agent in an organic solvent or a solvent-free release agent to the surface of the paper substrate. Has been done. The paper substrate used in this paper adhesive tape has a thickness of 10 by an extrusion method for the purpose of suppressing the penetration of the coating liquid as much as possible on the surface of the kraft stretched paper and maximizing the peelability. A base paper for release paper having a polyethylene film layer of about ˜25 μm is common.
However, the base paper for release paper manufactured by the method of laminating the polyethylene film described above is a paper manufacturing process in which the base paper for release paper is collected because polyethylene forms a strong continuous film and it is insoluble in water. Can not be reused, and is not preferable from the viewpoint of environmental protection.

In addition, as other release paper base paper, natural rubber, butadiene rubber, isoprene rubber, styrene butadiene copolymer, polyvinyl alcohol (PVA) solution, starch solution, etc. are coated on the surface of kraft stretch paper as a sealing agent. A base paper for release paper in which a sealing layer is formed and a release agent is applied to the surface is used (see Patent Document 1).
However, in this release paper base paper, the release agent silicone may infiltrate from pinholes or excessive permeation into the paper that occurs when applying the sealing layer, and after the adhesive layer is formed, the release layer of the release paper base paper When the pressure-sensitive adhesive layer is peeled from the forming surface, it may cause a peeling failure.

JP 2000-170097 A

  The present invention provides a release paper that has good release properties and can be disaggregated with water and has excellent environmental properties, and also provides an efficient method for producing the release paper, and further uses the release paper. It is an object of the present invention to provide a paper adhesive tape excellent in environmental properties, which is excellent in stability of peeling force and obtained by separation with water.

As a result of intensive studies to solve the above problems, the present inventor has made the base paper into a water-disintegrable base paper when the base layer and the intermediate layer are sequentially formed on one side of the base paper, and the base layer is made of polyvinyl alcohol. An intermediate layer is formed from a liquid composition for forming a sealing layer containing a water disintegrating sealant, which is a mixture of esterified starch, and the intermediate layer is formed from a liquid composition for forming an intermediate layer containing specific components, and the intermediate layer is applied. By making the amount 20 to 100% by mass of the coating amount of the sealing layer in solid content by mass%, further laminating the release layer on the surface of the formed intermediate layer, and making the air permeability of the release paper 5000 seconds or more The present inventors have found that the above problems can be solved and have completed the present invention.

That is, in the present invention, in the release paper obtained by laminating the base paper, the sealing layer, the intermediate layer, and the release layer in this order, the base paper is a water-disintegratable base paper, and the seal layer is a mixture of polyvinyl alcohol and esterified starch. An intermediate layer comprising a mixture of a styrene-butadiene copolymer and an acrylic thickener, wherein the intermediate layer is formed from a liquid composition for forming a sealing layer containing a water disintegrating sealant, and the intermediate layer is a water disintegrating interlayer forming agent. It is formed from a liquid composition for formation (excluding those containing acetylated starch and / or phosphate esterified starch), and the coating amount of the intermediate layer is 20% of the coating amount of the filler layer when the coating amount of the intermediate layer is mass%. It is -100 mass%, The release paper can be disaggregated with water, and the air permeability of a release paper is 5000 second or more, It provides the release paper characterized by the above-mentioned.
Moreover, this invention provides the release paper whose coating amount of a sealing layer is 1-5 g / cm < ² > by solid content mass in the said release paper.

Moreover, this invention provides the release paper whose coating amount of an intermediate | middle layer is 0.5-3 g / cm < ² > by solid content mass in the said release paper.
Moreover, this invention provides the release paper whose coating amount of a release layer is 0.1-3 g / cm < ² > by solid content mass in the said release paper .
Further, the present invention provides the release paper, wherein the viscosity of the liquid composition for forming a sealing layer is 300 to 1000 mPa · s, and the viscosity of the liquid composition for forming an intermediate layer is 300 to 1000 mPa · s. It is to provide.
The present invention also provides a release paper in which the release layer is formed from a release layer-forming liquid composition containing an addition reaction type aqueous emulsion silicone.
Moreover, this invention provides the release paper in which the liquid composition for release layer formation contains polyether silicone as a wettability improvement agent further in the said release paper.
The present invention also provides a paper pressure-sensitive adhesive tape characterized in that a pressure-sensitive adhesive layer that can be dissociated with water or an aqueous alkaline solution is laminated on the surface of the release paper on which the release layer is not formed.

The present invention also relates to a method for producing a release paper comprising a base paper, a seal layer, an intermediate layer, and a release layer, which are laminated in this order, and a seal containing a water disintegrating sealant that is a mixture of polyvinyl alcohol and esterified starch. A mixture of a styrene-butadiene copolymer, which is a water disintegrating intermediate layer forming agent, and an acrylic thickener is formed by applying a liquid composition for layer formation onto a base paper which is a water disintegrating base paper to form a sealing layer. An intermediate layer-forming liquid composition (excluding those containing acetylated starch and / or phosphate esterified starch) having a viscosity of 300 to 1000 mPa · s is applied onto the sealing layer and intermediate A layer is formed, the coating amount of the intermediate layer is 20% by mass of the solid layer and the coating amount of the sealing layer is 20 to 100% by mass, the release paper can be dissociated with water, and the air permeability of the release paper is 5000 In seconds There is provided a method for manufacturing release paper, characterized in that to produce a release paper characterized by Rukoto.
Moreover, this invention provides the manufacturing method of the release paper which forms these layers in-line in order of a sealing layer, an intermediate | middle layer, and a release layer in the manufacturing method of the said release paper.
Furthermore, the present invention provides a method for producing a release paper in which the sealing layer and the intermediate layer are formed using flexographic printing and the release layer is formed using a bar coater. Is.

  The release paper of the present invention has good releasability, can be disaggregated with water, and has excellent environmental properties. Moreover, the manufacturing method of the release paper of this invention can manufacture a release paper efficiently. Furthermore, the paper adhesive tape of the present invention obtained by using the release paper of the present invention can be disaggregated with water or an aqueous alkaline solution, and is excellent in environmental properties.

Examples of the base paper include water-disintegrable base paper, and specific examples include water-disintegrable paper mainly composed of unbleached kraft paper, bleached kraft paper, high-quality paper, glassine paper, carboxymethylcellulose, and the like. Since the base paper is water-disintegrating, the base paper for release paper can be collected and reused in the paper making process.
Although there is no restriction | limiting in particular in the thickness of a base paper, Usually, basic weight should just be 10-300 g / m < ² >, Preferably it is 20-200 g / m < ² >.

The filling agent used in the sealing layer is Ru water defibration properties sealers der is a mixture of polyvinyl alcohol and esterified starch.
As polyvinyl alcohol, any of fully saponified polyvinyl alcohol having a saponification degree of 95 mol% and partially saponified polyvinyl alcohol having 70 to 90 mol% can be used. In addition, compounds obtained by modifying polyvinyl alcohol, such as acetoacetylated polyvinyl alcohol, esterified products of polyvinyl alcohol and polyvalent carboxylic acid, carboxy-modified polyvinyl alcohol, sulfonic acid-modified polyvinyl alcohol, and the like can also be used.

The sealing agent for forming the sealing layer is preferably applied in the form of an aqueous solution or an aqueous dispersion. In this case, it is water vapor that evaporates in the drying step of the sealing layer, and the organic solvent is not discharged, which is excellent in environmental properties.

In order to form the sealing layer on one surface of the base paper, the sealing agent forming liquid composition obtained by diluting the sealing agent with water is applied to one surface of the base paper. Can do.
The viscosity of the liquid composition for forming a sealing layer is preferably 300 to 1000 mPa · s . By doing in this way, while giving the sealing effect to a base paper, high-speed coating property can be kept favorable.
The coating amount of the sealing layer is preferably 1 to 5 g / cm ² in solid weight, 2 to 4 g / cm ² is more preferable. Before applying the intermediate layer forming agent on the surface of the sealing layer, it is preferable to dry the sealing layer. By doing in this way, the air permeability of a release paper can be enlarged.

An intermediate layer forming agent used in the intermediate layer is a water-defibration properties intermediate layer forming agent, a styrene - Ru butadiene copolymer der.
The intermediate layer forming agent for forming the intermediate layer is preferably applied as an aqueous solution or an aqueous dispersion. In this case, it is water vapor that evaporates in the drying step of the intermediate layer, and the organic solvent is not discharged, which is excellent in environmental properties.
The intermediate layer can be formed on the surface of the sealing layer by applying a liquid composition for forming an intermediate layer obtained by diluting the intermediate agent with water to the surface of the sealing layer.
The viscosity of the intermediate layer forming liquid composition is preferably 300 to 1000 mPa · s . By doing so, it is possible to sufficiently cover the excessive soaking and pinholes that may occur in the sealing layer to increase the air permeability and to keep the high-speed coating property favorable.

The coating amount of the intermediate layer is preferably 0.5 to 3 g / cm ² in solid weight, 1 to 2 g / cm ² is more preferable.
In the present invention, by forming the intermediate layer, penetration of the release agent can be prevented, and after the formation of the pressure-sensitive adhesive layer, the pressure-sensitive adhesive layer can be prevented from being peeled off from the surface of the release paper base paper.
In the present invention, the coating amount of the intermediate layer is 20% by mass to 20% by mass of the coating amount of the filler layer in terms of solid content by mass%, preferably 25-80% by mass, and particularly preferably 30-60% by mass. By doing in this way, the air permeability of a release paper can be enlarged. The air permeability at the time of forming the intermediate layer is preferably 5000 seconds or more. By doing so, it is possible to suppress the penetration of the release agent when forming the release layer.

The release agent used for the release layer is a water disintegrating release agent. For example, an addition reaction type silicone is preferable because it has excellent curability. The addition reaction type silicone may be used as an emulsion, or may be used as a solution dissolved or dispersed in a solvent. However, when used as an aqueous emulsion, there is no discharge of organic solvent in the drying process, and environmental friendliness. Is preferable. A well-known platinum catalyst can be mix | blended with an addition reaction type | mold silicone as a curing catalyst.
The release layer can be formed on the surface of the intermediate layer by applying a release layer forming liquid composition obtained by diluting the release agent with water to one surface of the base paper.

The coating amount of the release layer is preferably 0.1 to 3 g / cm ^{2 and} more preferably 0.3 to ² g / cm ² in terms of solid mass. If it is less than 0.1 g / cm ² , the peelability may be inferior. If it is more than 3 g / cm ² , the amount of silicone transferred to the pressure-sensitive adhesive layer surface increases, resulting in a decrease in the adhesive strength or tack of the paper adhesive tape. May cause.
In addition, the air permeability after forming the release layer is 5000 seconds or more. By doing so, even when the adhesive layer is formed with few pinholes, there is no drop of the adhesive, and the release force is stable. Can be kept in.
The aforementioned first sealing layer, the purpose is not impaired scope of the present invention, if necessary, can be suitably contain a thickening agent. Examples of the thickener include aqueous polymer compounds such as sodium alginate, sodium polyacrylate, and carboxymethylcellulose.
The intermediate layer contains an acrylic thickener.
Further, when the release agent is emulsion silicone, a wettability improver can be appropriately contained. As the wettability improver, a known wettability improver such as polyether silicone can also be used.

When these layers are formed by in-line in the order of the sealing layer, the intermediate layer, and the release layer, in-line refers to the process of continuously feeding the base paper and applying the sealing agent to form the sealing layer, Applying and drying an intermediate layer forming agent for forming an intermediate layer on the surface of the sealing layer, and further applying and drying a release agent for forming a release layer on the surface of the intermediate layer This is done continuously.
In this continuous process, it is preferable to dry the sealing layer after applying the sealing agent to form the sealing layer and before applying the intermediate layer forming agent to the surface of the sealing layer.
This continuous process will be described with reference to FIG.

The base paper is continuously fed from the base paper feed roll 1, and the sealing layer forming liquid composition is continuously applied to one surface of the base paper in the sealing layer forming step 2 to form the sealing layer. Various coating methods are used as the coating method in the sealing layer forming step 2, and a coating method by flexographic printing is particularly preferable.
It is preferable that the base paper on which the sealing layer is formed is continuously fed into the sealing layer dryer 5 and dried. In drying the sealing layer, the drying temperature is preferably 100 to 220 ° C, more preferably 130 to 200 ° C, and particularly preferably 150 to 180 ° C. In drying the sealing layer, the drying time is preferably 5 seconds to 2 minutes, more preferably 10 to 60 seconds, and particularly preferably 15 to 30 seconds.

In drying the sealing layer, it is preferable to send in air, and the air feeding speed (wind speed) is preferably 0.2 m / sec to 10 m / sec, particularly preferably 2 m / sec to 5 m / sec.
Next, the base paper on which the sealing layer is formed is continuously fed to the intermediate layer forming step 3, and the intermediate layer forming liquid composition is continuously applied to the surface of the sealing layer to form the intermediate layer. . Various coating methods are used as the coating method in the intermediate layer forming step 3, and a coating method by flexographic printing is particularly preferable.

  In addition, as a manufacturing method of the release paper of the present invention, by forming the sealing layer and the intermediate layer using flexographic printing, the liquid composition for forming the sealing layer has a relatively high viscosity (for example, 300 to 1000 mPa · s). It is possible to apply a thin film to the product and the liquid composition for forming an intermediate layer, and a uniform coated surface can be formed. If the viscosity is too low, there are many penetrations into the base paper, and the sealing function and function as an intermediate layer may not be exhibited. On the other hand, when the viscosity is too high, leveling is difficult when the liquid composition for forming a sealing layer and the liquid composition for forming an intermediate layer are applied, and the state of the coated surface is likely to deteriorate.

The base paper on which the intermediate layer is formed is continuously fed into the intermediate layer dryer 6 and dried. The intermediate layer is preferably dried under the same conditions as the sealing layer.
Next, the base paper on which the intermediate layer is formed is continuously fed into the release layer forming step 4, and the release layer forming liquid composition is continuously applied to the surface of the intermediate layer to form the release layer. Various coating methods are used as the coating method in the release layer forming step 4, and a coating method using a bar coater is particularly preferable. By forming the release layer using a bar coater, it is possible to apply a release layer-forming liquid composition having a relatively low viscosity (for example, 300 mPa · s or less). Can be formed. The surface state of the surface of the release layer greatly contributes to the releasability, and in order to obtain a good surface state, it is necessary to apply and level a low-viscosity release layer forming liquid composition.

The base paper on which the release layer is formed is continuously fed to the release layer dryer 7 and dried. The drying of the release layer is preferably set as appropriate from the range of drying conditions for the sealing layer.
The sealing layer, the intermediate layer, and the release layer are sequentially formed by the above method to produce a release paper, and the produced release paper is taken up by the release paper take-up roll 8.
In the paper pressure-sensitive adhesive tape of the present invention, a pressure-sensitive adhesive layer that can be dissociated with water or an aqueous alkali solution is laminated on the surface of the release paper where the release layer is not formed.

  An acrylic pressure-sensitive adhesive is suitably used as the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer. Examples of acrylic adhesives that can be disaggregated with water or an aqueous alkaline solution include acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, monoalkylmaleic acid, monoalkylitaconic acid, monoalkylfumaric acid, and the like. Ethylenically unsaturated carboxylic acid-containing monomers, butyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, stearyl (meth) acrylate, etc. Examples thereof include a pressure-sensitive adhesive mainly comprising a monomer such as a (meth) acrylic acid alkyl ester monomer having an alkyl group of several 4 to 18 or two or more copolymers of the monomers.

The thickness of the pressure-sensitive adhesive layer may be appropriately selected depending on the application, but is usually preferably 1 to 100 μm, particularly preferably 5 to 50 μm.
As a method of providing a pressure-sensitive adhesive layer that can be dissociated with water or an aqueous alkali solution on the surface of the release paper on the base paper where the release layer is not formed, for example, after applying the heat-sensitive adhesive to the surface of the base paper on the release layer-forming surface And a method of winding around a core material made of cylindrical metal, paper, plastic or the like. In the wound body wound up by such a method, the pressure-sensitive adhesive layer provided on the release layer of the base paper is adhered to the surface of the base paper where the release layer is not formed.
As a coating method, for example, a bar coating method, a knife coating method, a gravure coating method, a roll coating method, a die coating method, or the like can be used.
The heat treatment temperature may be appropriately selected to obtain the desired hardness, but is usually preferably 50 to 150 ° C, more preferably 60 to 120 ° C.

Hereinafter, the present invention will be described in more detail with reference to examples. In addition, this invention is not restrict | limited at all by these examples.
The performance evaluation of the release paper obtained in the example of the present invention or the comparative example was performed by the following method.

Measurement of Peeling Force Acrylic emulsion adhesive (trade name “AT-22C” manufactured by Syden Chemical Co., Ltd.) was applied to the surface of the release layer of the produced release paper so that the coating amount after drying was 40 g / m ^2. And dried at 100 ° C. for 2 minutes to form an adhesive layer. A high-quality paper (basis weight 64 g / m ² ) was pasted on the surface of the pressure-sensitive adhesive layer as a surface base material to prepare a pressure-sensitive adhesive paper. After leaving for 1 week in an environment of 23 ° C. and 1 week in an environment of 60 ° C. and 95% RH (after-acceleration peel force), the peel strength of the surface substrate and the release layer is in accordance with JIS-Z0237. The peel strength was measured by peeling the surface substrate at a speed of 300 mm / min in the 180 ° direction using a tensile tester in an atmosphere of 23 ° C. and 50% RH.

Release paper disaggregation test 50 g of the prepared release paper was cut into 5 cm × 5 cm square, added to 1200 mL of water (20 ° C.), and stirred for 5 minutes by a standard disintegrator of JIS P8209. Next, using the slurry after disaggregation (solid content of 6.25 g), a handmade sheet (25 cm × 25 cm) is prepared by a square handsheet sheet machine, sandwiched between dehydrated filter papers, and reciprocated twice by a 20 kg press roll. Pressing at a pressure of 3.5 kg / cm ² . Next, after drying for 2 hours with a blow dryer while sandwiched between the filter papers, the handsheet was peeled from the filter papers. The undissolved material contained in the peeled handsheet was observed, and the disintegration property of the release paper was evaluated in the following three stages. Note that undissociated material is observed as black spots when a handsheet is placed on a scattering plate (for example, ground glass having a light emitter inside) in a state in which a part of the release paper is not separated and remains small. Can do.
○: No undissociated product is observed.
Δ: Some undissociated material was observed.
X: Many undissociated substances were observed.

Disaggregation test of paper adhesive tape The produced paper adhesive tape was evaluated in the same manner as in the disaggregation test of the release agent (2) above.
Air Permeability The air permeability of the produced release paper was measured using a Oken air permeability smoothness tester (Asahi Seiko Co., Ltd.).

Example 1
Preparation of liquid composition for forming a sealing layer Polyvinyl alcohol having an average polymerization degree of 3000 (manufactured by Kuraray Co., Ltd., trade name “Kuraray Poval PVA203”) and esterified starch (manufactured by Shikishima Starch Co., Ltd., trade name “MC-3000”) )) (Solid content mass ratio (polyvinyl alcohol: esterified starch) = 70: 30) by boiling and dissolving in water to a solid content concentration of 20 mass% and a viscosity of 500 mPa · s (23 ° C.) A forming liquid composition was prepared.
Preparation of liquid composition for forming intermediate layer 100 parts by mass of styrene-butadiene copolymer emulsion (manufactured by JSR Co., Ltd., trade name “JSR0614”, solid concentration 48% by mass), acrylic thickener (Toa Gosei Co., Ltd.) ), Trade name “A-7185”) 1.6 parts by mass was stirred and mixed to prepare a liquid composition for forming an intermediate layer having a solid content concentration of 47.5% by mass and a viscosity of 830 mPa · s (23 ° C.).

Preparation of Release Layer Forming Liquid Composition Addition Reaction Type Emulsion Silicone (Arakawa Chemical Industries Co., Ltd., trade name “Silicolys 902”, solid content concentration: 40% by mass) 100 parts by mass, emulsion silicone curing platinum catalyst (Arakawa Chemical) After uniformly mixing 15 parts by mass of Kogyo Co., Ltd., trade name “Silicolys 903CA”, solid content concentration 40% by mass, polyether silicone (manufactured by Toray Dow Corning Co., Ltd., trade name “FZ-77”). ]] 0.5 parts by mass and 650 parts by mass of pure water were added and mixed to prepare a liquid composition for forming an emulsion silicone release layer having a solid content concentration of 6% by mass.

Production of Release Paper A release paper was produced using the continuous production machine for release paper shown in FIG. First, a kraft paper (made by Oji Paper Co., Ltd., trade name “Ogi RC Shinchoshi 73g”) is continuously sent out from the base paper feed roll 1, and a liquid composition for forming a sealing layer in the sealing layer forming step 2 Was continuously applied to one surface of the base paper by flexographic printing so that the solid content was 3 g / m ² , thereby forming a sealing layer.
The base paper on which the sealing layer is formed is continuously fed inline to the drying machine 5 of the sealing layer, and the sealing layer is continuously dried at a wind speed of 3 m / sec, a drying temperature of 160 ° C., and a drying time of 15 seconds. I went there.

Next, the base paper on which the sealing layer is formed is continuously fed in-line to the intermediate layer forming step 3 so that the liquid composition for forming the intermediate layer has a solid mass of 1 g / m ^2. The intermediate layer was formed by continuously applying to the surface of the layer by flexographic printing.
The base paper on which the intermediate layer was formed was continuously fed into the intermediate layer dryer 6, and the intermediate layer was continuously dried at a wind speed of 3 m / sec, a drying temperature of 160 ° C., and a drying time of 15 seconds.

Next, the base paper on which the intermediate layer is formed is continuously fed in-line to the release layer forming step 4 so that the release layer forming liquid composition has a solid content mass of 1 g / m ² . The surface was continuously applied using a bar coater to form a release layer.
The base paper on which the release layer was formed was continuously fed into the release layer dryer 7 and dried at a wind speed of 3 m / sec, a drying temperature of 160 ° C., and a drying time of 30 seconds to produce a release paper. The release paper was continuously wound up by a release paper winding roll 8.

Preparation of Paper Adhesive Tape On the release layer-forming surface of the base paper in the prepared release paper, an application amount after drying an acrylic emulsion adhesive (trade name “AT-22C” manufactured by Syden Chemical Co., Ltd.) is 40 g / After applying to m ² and drying at 100 ° C. for 2 minutes, a paper pressure-sensitive adhesive tape was prepared by winding the paper core material in a roll.

( Reference Example 2)
A release paper was prepared in the same manner as in Example 1 except that the following sealing layer-forming liquid composition was used, and a paper adhesive tape was further prepared.
Preparation of liquid composition for forming a sealing layer 100 parts by mass of a styrene-butadiene copolymer emulsion (manufactured by JSR Co., Ltd., trade name “JSR0614”, solid concentration 48% by mass), acrylic thickener (Toagosei ( Co., Ltd., trade name “A-7185”) 1.6 parts by mass was prepared by stirring and mixing to prepare a liquid composition for forming a sealing layer having a solid content concentration of 47.5% by mass and a viscosity of 830 mPa · s (23 ° C.). did.

(Comparative Example 1)
Except for forming a release layer using the following release layer forming liquid composition without forming a sealing layer and an intermediate layer on the surface of kraft paper (basis weight 80 g / m ² ) laminated with polyethylene as a base paper Produced a release paper in the same manner as in Example 1, and further produced a paper adhesive tape.
Preparation of Release Layer Forming Liquid Composition Addition reaction type emulsion silicone (manufactured by Toray Dow Corning Co., Ltd., trade name “SRX-211”) 100 parts by mass, platinum catalyst (manufactured by Toray Dow Corning Co., Ltd., 0.6 parts by mass of a trade name “SRX-212”) was added and dissolved in toluene to prepare a liquid composition for forming a release layer having a solid content concentration of 6% by mass.

(Comparative Example 2)
Using the following liquid composition for forming a sealing layer, it is continuously applied to one surface of the base paper by flexographic printing so as to have a solid content mass of 4 g / m ² , thereby forming a sealing layer. Except that was not formed, a release paper was prepared in the same manner as in Example 1, and a paper adhesive tape was further prepared.
Preparation of liquid composition for forming a sealing layer 100 parts by mass of a styrene-butadiene copolymer emulsion (manufactured by JSR Co., Ltd., trade name “JSR0614”, solid concentration 48% by mass), acrylic thickener (Toagosei ( Co., Ltd., trade name “A-7185”) 1.6 parts by mass was prepared by stirring and mixing to prepare a liquid composition for forming a sealing layer having a solid content concentration of 47.5% by mass and a viscosity of 830 mPa · s (23 ° C.). did.

(Comparative Example 3)
Except for forming the release layer by applying the release layer-forming liquid composition used in Example 1 to one surface of the base paper without forming the sealing layer and the intermediate layer, the same procedure as in Example 1 was performed. A release paper was prepared, and a paper adhesive tape was further prepared.
The release paper and paper adhesive tape prepared in the above examples and comparative examples were evaluated by the above test. The evaluation results are shown in Table 1.

It is the schematic of an example of the manufacturing method of the release paper of this invention which has formed these layers in order of the sealing layer, the intermediate | middle layer, and the peeling layer by in-line.

Explanation of symbols

1: Feed roll 2 of base paper: Seal layer forming step 3: Intermediate layer forming step 4: Release layer forming step 5: Seal layer dryer 6: Intermediate layer dryer 7: Release layer dryer 8: Release Paper take-up roll

Claims (11)

In release paper that is laminated in the order of base paper, sealing layer, intermediate layer, release layer,
The base paper is a water disintegrating base paper,
The sealing layer is formed from a liquid composition for forming a sealing layer containing a water disintegrating sealing agent that is a mixture of polyvinyl alcohol and esterified starch ,
A liquid composition for forming an intermediate layer comprising a mixture of a styrene-butadiene copolymer, which is a water disintegrating intermediate layer forming agent, and an acrylic thickener (however, an acetylated starch and / or a phosphate esterified starch) Excluding those contained.)
The coating amount of the intermediate layer is 20% by mass of the solid layer and 20 to 100% by mass of the coating amount of the sealing layer, the release paper can be disaggregated with water, and the air permeability of the release paper is 5000 seconds or more. Release paper characterized by. The release paper according to claim 1, wherein the coating amount of the sealing layer is 1 to 5 g / cm ² in terms of solid mass. The release paper according to claim 1, wherein the coating amount of the intermediate layer is 0.5 to ³ g / cm ² in terms of solid mass. The release paper according to claim 1, wherein the coating amount of the release layer is 0.1 to 3 g / cm ² in terms of solid mass. The release paper according to any one of claims 1 to 4 , wherein the viscosity of the liquid composition for forming a sealing layer is 300 to 1000 mPa · s, and the viscosity of the liquid composition for forming an intermediate layer is 300 to 1000 mPa · s. The release paper according to any one of claims 1 to 5 , wherein the release layer is formed from a liquid composition for forming a release layer containing an addition reaction type aqueous emulsion silicone. The release paper according to claim 6 , wherein the release layer forming liquid composition further comprises polyether silicone as a wettability improver. Paper adhesive tape water or the peeling layer unformed surface of the base paper in the release paper according to any one of claims 1 to 7, characterized in that the fragmenting possible pressure-sensitive adhesive layer by an alkaline aqueous solution are stacked. A liquid composition for forming a sealing layer comprising a water disintegrating sealing agent, which is a mixture of polyvinyl alcohol and esterified starch, in a method for producing a release paper in which a base paper, a sealing layer, an intermediate layer, and a release layer are laminated in this order. Is applied to a base paper that is a water-disintegrating base paper to form a sealing layer, and the viscosity of the water-disintegrating intermediate layer forming agent is a viscosity of 300 to 300, including a mixture of a styrene-butadiene copolymer and an acrylic thickener. An intermediate layer is formed by applying a liquid composition for forming an intermediate layer of 1000 mPa · s (excluding those containing acetylated starch and / or phosphate esterified starch) onto the sealing layer. The coating amount of the layer is 20% by mass of the coating amount of the filler layer, the solid content is 20% by mass, the release paper can be dissociated with water, and the air permeability of the release paper is 5000 seconds or more. Features and Method for manufacturing release paper, characterized in that to produce a release paper that. The method for producing a release paper according to claim 9 , wherein the layers are formed in-line in the order of the sealing layer, the intermediate layer, and the release layer. The method for producing a release paper according to claim 9 or 10 , wherein the sealing layer and the intermediate layer are formed using flexographic printing, and the release layer is formed using a bar coater.

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