JPS58214596A - Production of processing base paper - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing base paper for processing, and more specifically to a coating containing modified polyvinyl alcohol/l/ (hereinafter polyvinyl alcohol-1v is abbreviated as PVA) containing silicon in the molecule. A processing agent that coats paper with an agent that prevents organic solvents and processing agents from penetrating or absorbing into the paper layer, increasing the retention of the processing agent on the paper surface and significantly increasing the effect of the processing agent. Concerning a method for producing base paper.

Release paper or process paper that has a base paper coated with a release agent such as silicone resin to improve its releasability against adhesives, or base paper that has a base paper coated with a slip agent such as silicone resin to improve its ability to reduce frictional resistance; Masking paper is used to prevent paint from adhering to unnecessary areas, and processed paper such as transfer paper, which is used to transfer the printed image onto the substrate after printing on base paper, is easy to use. Due to its nature, it has become widely used in recent years. The base paper used for these processed papers has properties that allow the processing agent applied on it to be efficiently retained on the surface without penetrating or being absorbed into the base paper, allowing the processing agent to fully demonstrate its effects. That is, it is strongly required to have a high permeation prevention effect, that is, barrier properties against processing agents or organic solvents used together with processing agents. However, base paper is generally porous, and organic solvents or processing agents can be easily absorbed into the paper layer in that state, making it impossible to increase the yield on the surface. Therefore, various methods have been considered in the past, but each has its own advantages and disadvantages, and the current situation is that a satisfactory level has not yet been reached. For example, in the base paper for release paper, PT
A. A method of preventing the release agent solution from penetrating into the paper layer is to apply a water-soluble resin such as carboxymethyl cellulose (CMC) or to laminate a polyethylene film. However, for example, PVA, OMC! The method of applying water-soluble resins, such as However, the resulting release paper base paper has insufficient barrier properties against organic solvents or release agents, and it has been difficult to produce an fc type release paper with excellent release properties against adhesives. In addition, in the method of laminating polyethylene film, the resulting release paper base paper has a high barrier property against organic solvents or release agents, and is an excellent method in that it can improve the release property against adhesives. When laminating polyethylene films, the production speed cannot be increased, resulting in poor productivity.
The inventors of the present invention have conducted intensive studies on a method for producing base paper for processing that overcomes the above-mentioned drawbacks, has excellent barrier properties against organic solvents or processing agents, and has high productivity. By coating the base paper with a coating solution containing Did they discover the scale of manufacturing through productivity and complete the invention? Ta.

The present invention will be explained in more detail below.

The modified PVA containing silicon in the molecule used in the present invention may be any one containing silicon in the molecule, but
Those in which the silicon contained in the molecule has a reactive substituent such as an alkoxyl group, an acyloxyl group, a silanol group which is a hydrolyzate thereof, or a salt thereof are particularly preferably used.

Methods for producing such modified PVA include a method in which silicon is introduced into OPVA or modified polyvinyl acetate containing a carboxyl group or a hydroxyl group by post-modification using a silylating agent; Examples include a method of saponifying a copolymer with a polymer. In the method of post-modifying PVA or modified polyvinyl acetate using a silylating agent, for example, the silylating agent is added to an organic solvent that does not react with the silylating agent, such as benzene, toluene, xylene, hexane, hegetane, ether, or acetone. Powdered PVA or the above modified polyvinyl acetate is suspended in the solution with stirring, and the silylating agent and PVA or the above modified polyvinyl acetate are reacted at a temperature ranging from room temperature to the boiling point of the silylating agent. silicon-containing modified P by saponifying the vinyl acetate unit by
You can get VA. Examples of silylating agents used in post-modification include organohalogensilanes such as trimethylchlorosilane, dimethyldichlorosilane, methyltrichlorosilane, vinyltrichlorosilane, diphenyldichlorosilane, and triethylfluorosilane, trimethylmethoxysilane, and dimethyldiacetoxy. Organosilicon esters of silana, organoalkoxysilanes such as trimethylmethoxysilane and dimethyldimethoxysifun, organosilanols such as trimethylsifunol and diethylsilanediol, aminoalkylsifunes such as N-amine ethylaminoglohil trimethoxysifun,
Examples include organosilicon isocyanates such as trinosilicone isocyanate. The rate of introduction of the silylating agent, that is, the degree of modification, can be arbitrarily adjusted by adjusting the amount of the silylating agent used and the reaction time. The polymerization degree and saponification degree of the obtained silicon-containing modified PVA are determined by the P used.
The degree of polymerization and saponification of VA or the degree of polymerization and saponification reaction of the above-mentioned modified polyvinyl acetate can be adjusted as desired.

In addition, in a method of saponifying a copolymer of a vinyl ester and a silicon-containing olefinic unsaturated monomer, for example, a vinyl ester and a silicon-containing olefinic unsaturated monomer are mixed in alcohol using a fusical initiator. Silicon-containing modified PVA can be obtained by copolymerizing the copolymer and then saponifying the copolymer by adding an alkali or acid catalyst to the alcohol solution of the copolymer. Vinyl esters used in the above method include vinyl acetate, vinyl propionate, vinyl formate, etc., but vinyl acetate is preferred from an economical standpoint.

Examples of the silicon-containing olefinically unsaturated monomer used in the above method include vinylsilane represented by the following formula (1) and (meth)acrylamide-alkylsilane represented by (I).

Te1m CHs = CH-(OH2)n-83-(R2)3m
(1) [Here, n is 0 to 4, m is 0 to 2, and 1 is an alkyl group with a prime number of 1 to 5 (methyl, 1, ethyl, etc.), R
an alkoxyl group or an acyloxyl group having a 2-dimensional prime number of 1 to 40 (herein, the alkoxyl group or acyloxyl group may have an oxygen-containing substituent), 几3 is a hydrogen atom or a methyl group, R4 is hydrogen Atom or prime number 1~
The alkyl group R5 represents an alkylene group having a prime number of 1 to 5 or a divalent organic residue in which chain atoms are bonded to each other via oxygen or nitrogen, respectively. In addition, when two R1s exist in the same monomer, only R1 may be the same or different,
They may be different.

Specific examples of the vinylsilane represented by formula (1) include vinyltrimethoxysilane, vinyltriatoxysilane, vinyltris-(β-methoxyethoxy)silane, vinyltriacetoxysilane, allyltrimethoxysilane, and allyltriacetoxysilane. , vinyl dithylmethoxysilane, vinyldimethylmethoxysilane, vinylmethyljethoxysilane, vinyldimethylmethoxysilane, vinylmethyljethoxysilane, vinyldimethylmethoxysilane, vinyldimethylmethoxysilane, vinyltriisopropoxysilane, vinyltributoxysilane,
Vinyltrihexyloxysilane, vinylmethoxydihexyloxysilane, vinyldimethoxyoctyloxysilane, vinylmethoxydioctyloxysilane, vinyltrioctyloxysilane, vinylmethoxydifuryloxysilane, vinyldimethoxyfuryloxysilane, vinylmethoxysilane Dioleyloxysilane, vinyldimethoxyoleyloxysilane, and general formula %) (where R1 and m are the same as above, and X represents 1 to 2o)
Examples include polyethylene glycolized pinylsilone represented by: Further, specific examples of rel(meth)acrylamide-alkylsilane represented by the formula (summer) include:
3-(meth)acrylamide-propyltrimethoxysilane, 3-(meth)acrylamide-globiltriethoxysilane, 3-(meth)acrylamide-propyltri(β-methoxyethoxy)sifun, 2-(meth)acrylamide-2 - methylpropyltrimethoxysilane,
2-(meth)acrylamido-2-methylethyltrinotoxysilone, N-(2-,(meth)acrylamidoethyl)L-aminopropyltrimethoxysilane, 3-
(Meth)acrylamide-10-hydrotriacetoxysilane, 2-(meth)acrylamide-ethyltrimethoxysilane, 1-(meth)acrylamide+rutrimethoxysilane, 3-(meth)acrylamide-gropylmethyldimethoxysilane, 3-(meth)acrylamidopropyldimethylmethoxysilone, 5-(N-methyl-
(meth)acrylamide)-propyltrimethoxysilane and the like.

In addition, when copolymerizing the vinyl ester and the silicon-containing olefinic unsaturated monomer to produce the modified PVA used in the present invention, it is necessary to copolymerize with other monomers other than the above two components. unsaturated monomers such as styrene, apyl vinyl ether, vinyl versatate, (meth)acrylamide, olefins such as ethylene, propylene, α-hexene, α-octene, (
meth)acrylic acid, crotonic acid, (anhydrous)maleic acid,
Unsaturated acids such as fumaric acid and itaconic acid, and their alkyl enethers and alkali salts, sulfonic acid-containing monomers and their alkali salts such as 2-acrylamido-2-methylpropanesulfonic acid, trimethy#-3-(1 -(meth)acrylamide-1゜1-dimethylpropy/l/) ammonium chloride, trimethytv-5-(f-(meth)acrylamidopropyl) ammonium chloride, 1-viny)
It is also possible to have a cationic monomer such as V-2-methylimidazole and its quaternized product present in a small proportion.

Modified P containing silicon in the molecule used in the present invention
Among the above-mentioned two methods for producing VA, the method of saponifying a copolymer of a vinyl ester and a silicon-containing olefinic unsaturated monomer is easy to industrially produce and
It is preferably used in terms of the homogeneity of the resulting modified PVA.

In addition, in the method of saponifying a copolymer with a silicon-containing olefinically unsaturated monomer, the saponified copolymer with a monomer represented by formula (1) has a high alkalinity and viscosity stability of an aqueous solution. It has the advantage of being easy to use, such as having excellent stability against alkalis when made into an aqueous solution.Saponified copolymers with monomers represented by the rectangular formula (1) have poor stability against alkalis, but when dissolved in aqueous solutions, It has the advantage that it is difficult to foam, and the film obtained after drying has slightly better barrier properties against organic solvents or processing agents, and it is preferable to select and use it as appropriate depending on the purpose and usage conditions.

Modified PVA containing silicon used in the present invention
The silicon content, degree of saponification, and degree of polymerization are appropriately selected depending on the purpose and are not particularly limited. The effect of silicon atoms is exhibited even at a relatively small content, and usually 0.01 to 10 mol% as a silicon-containing monomer unit, preferably 0.
．． It is selected from the range of 1 to 2.5 mo/L/%. The saponification degree is usually preferably in the range of 70 to 100 molar ratio. Further, the degree of polymerization is usually selected from the range of 300 to 5,000.

When dissolving the modified PVA used in the present invention in water, a homogeneous aqueous solution is usually obtained by adding an alkali such as sodium hydroxide to the modified PVAN water and heating it with stirring. be able to.

The coating solution used in the present invention is, as described above, modified PV
A=i It can be prepared by dissolving in water, but in this case, the concentration of modified PVA is usually 0.2 to 20% by weight or 2 to 10% by weight considering workability etc. Selected from the range.

In addition, antifoaming agents and PVA may be added to the coating solution as necessary.
It is also possible to use a water-soluble resin or the like in combination.

The base paper used in the production of the base paper for processing of the present invention is not particularly limited, but glassine can be used, for example.

Furthermore, as described above, the term "base paper for processing" refers to paper that becomes a base material upon which a processing agent such as a release agent is applied to obtain a release paper or the like. In applying the coating solution to the base paper, any known method used for applying conventional water-soluble resins, such as a size press coater or a roll coater, can be employed. The coating amount varies depending on the porosity of the paper used, but usually the solid content of the modified PVA is 0.1 to 0.1.
About 10 f,/ltf, preferably 0,5 to 5 Q
/d is adopted. In addition, the release paper base paper obtained in this manner may be further calendered using a calender roll or the like, depending on the case.

According to the method of the present invention, the productivity of processed paper base paper is high because the coating method used in the conventional application of water-soluble resin can be adopted, and the obtained processing base paper has an effect of preventing penetration of organic solvents or processing agents. In addition, it has the characteristic of increasing the retention of the processing agent on the surface of the base paper, thereby significantly increasing the effect of the processing agent. As mentioned above, the reason why the high effect of preventing penetration of organic solvents or processing agents is exhibited is not fully elucidated, but the alkoxyl group and acyloxyl group in the silicon-containing modified PVA used as the coating material in the present invention The Sifunol group or its salt, which is a hydrolyzed product of silicon atoms bonded with groups, reacts with the cellulose fibers of paper, the pigments and aluminum compounds in paper, and also with the hydroxyl group or Schifnol group or its salt in modified PVA. It is presumed that this is because, due to their high properties, they bond with each other in the surface layer of the paper, forming a strong and uniform coating on the surface layer of the paper without the coating agent penetrating into the paper layer. Especially when the processing agent is silicone,
Due to the strong interaction between the silicon atoms in the modified PVA and silicone, it is silicone. As the silicone, silicone resin is mainly used here.

As is clear from the examples described later, the base paper for processing obtained by the method of the present invention exhibits excellent effects as a release paper on which a release agent such as silicone is applied. It exhibits excellent performance as a base paper for paper, and also as a base paper for various processed papers manufactured by applying organic solvents or processing agents.

The present invention will be explained in more detail with reference to Examples below.
The present invention is not limited by K. In addition, unless otherwise specified in the examples, "%" and "
"parts" represents weight basis.

Example 1 A copolymer of vinyltrimethoxysilane and vinyl acetate was saponified to contain 0.65 mol of silicon as vinyl silane units, and the degree of saponification of vinyl acetate units was 99.2 mol) V
%, modified PV containing silicon in the molecule with a degree of polymerization of 1600
I got an A. This modified PVA and fully modified PVAK: 2.
Dissolve the modified F in water containing 5% sodium hydroxide.
A 4% aqueous solution of VA was prepared. This aqueous solution was subjected to size press at 50°C using a test size press machine on high-quality paper with a basis weight of 72 g, and then dried at 105°C for 1 minute. Size press: nip pressure 18 to 9/C
It was carried out with N at 300 m/min. The coating amount in size press coating is 1. Of, /n/ (both sides). Next, this coated paper was subjected to a surface temperature of 80°C and a linear pressure of 100 kg/c.
A release paper base paper was obtained by calender finishing under the conditions of M. The air permeability of this release paper base paper was 100,000 seconds or more.

Next, apply silicone (Toray Silico-ys) to this release paper base paper.
RX357) I 00 parts, curing agent (SRX212) 0
．． 6 parts of toluene and 499.4 parts of toluene was coated with a bar coater until the dry solid content was 0.79. /d and dried at 120°C for 11 minutes to prepare a release paper. It was visually observed that the release agent mixture hardly penetrated into the paper layer and remained on the surface of the base paper. Next, this release paper 'ff: After being left to stabilize for one day, an acrylic adhesive was applied to the surface coated with the silicone release agent to a thickness of 70μ (wet thickness), and after drying in a 100°C oven for 1 minute,
Immediately, high-quality paper (509/d) was attached and pressed using a 5# pressure roller. This test piece was placed on a glass plate at a constant temperature and humidity of 20°C and relative humidity of 65e4.
Aging was performed for 24 hours under a load of m. The thus prepared test piece was cut into a 5clII width, and the peel strength of the release paper/adhesive was measured using an autograph at a peel angle of 180° C10 and a speed of sm/in. Results first
Shown in the table.

Comparative Example 1 Instead of the aqueous solution of modified PVA containing silicon in the molecule used in Example 1, unmodified PVA (clat
zboja-IV 117) C1) The same procedure as in Example 1 was carried out except that a 4% aqueous solution was used. The results are also shown in Table 1. Furthermore, the air permeable layer of the release paper base paper obtained in this way was 1
6.500 seconds, and it was observed that the release agent mixture permeated into the paper layer when it was applied.

Comparative Example 2 Instead of the modified PVA aqueous solution used in Example 1, a solution containing 2 mo/L'% of maleic anhydride units obtained by saponifying a copolymer of maleic anhydride and vinyl acetate,
Saponification degree of vinyl acetate unit is 91 mol, polymerization degree is 170
Example 1 except that a 4% aqueous solution of modified PVA of 0 was used.
I did the same thing. The results are also shown in Table 1. The air permeability of the release paper base paper obtained was 20,000 seconds, and it was observed that the release agent mixture permeated into the paper layer when the release agent mixture was applied.

Comparative Example 3 The same procedure as in Example 1 was carried out, except that instead of the aqueous solution of modified PVA used in Example 1, a 5% aqueous solution of OMC (manufactured by Dai-Kogyo Seiyaku Co., Ltd., Shichirogen HH) was used. The results are also shown in Table 1. The air permeability of the release paper base paper obtained was 25,000 seconds, and it was observed that the release agent mixture permeated into the paper layer when the release agent mixture was applied.

Comparative Example 4 The same procedure as in Example 1 was carried out, except that instead of the release paper base paper obtained in Example 1, a release paper base paper obtained by laminating polyethylene on kraft paper using an extrusion coating machine was used. In addition, the coating speed of polyethylene is the maximum speed (4
0 m/min). The amount of polyethylene applied is 10f.
/d.

The measurement results of peel strength are also shown in Table 1.

As shown in Table 1 below, it can be seen that according to the method of the present invention, a release paper base paper having a release performance comparable to that of polyethylene laminate paper can be produced at a significantly higher speed than the method using polyethylene laminate.

Examples 2 to 6 Peel strength was measured in the same manner as in Example 1, except that the following modified PVA aqueous solution was used instead of the modified PVA aqueous solution used in Example 1. The results are shown in Table 2.

The aqueous solution of modified PVA used in Example 2 contained silicon obtained by saponifying a copolymer of vinyltriethoxysilone and vinyl acetate at 1.0 mole/l' as a vinylsilane unit.
% content, degree of saponification in vinyl acetate/L' unit: 99.5 mo/
L/%, modified P containing silicon in the molecule with a degree of polymerization of 1400
This is a 3% aqueous solution of the modified PVA in which VA is dissolved in water containing 5-sodium hydroxide relative to the modified PVA.

The aqueous solution of modified PVA used in Example 5 contained 0.5 mow% silicon obtained by saponifying a copolymer of vinyltria-7toxysifune and vinyl acetate as a vinylsilane unit.
Contains a saponification degree of vinyl acetate unit of 98.5 mo/l'%
, is a 4-aqueous solution of modified PVA containing silicon in its molecules with a degree of polymerization of 1700.

The aqueous solution of modified PVA used in Example 4 contained 2.0 mo/L/% silicon obtained by saponifying a copolymer of vinyl dimethylacetoxysilane and vinyl acetate as vinyl silane units, and Modified PVAf containing silicon in the molecule with saponification degree of 96.5 mo/l'% and polymerization degree of 1350: Modified PVA dissolved in water containing 1.5% sodium hydroxide to the modified PVA. It is a 5% aqueous solution of

The aqueous solution of modified PVA used in Example 5 contained more than 0.5 mole of silicon obtained by saponifying a copolymer of vinyl methoxydioctyloxysiphon and vinyl acetate as a vinyl/L'siphon unit, Saponification degree of vinyl acetate unit: 98.
This is a 6% aqueous solution of modified PVA containing silicon in the molecule with a polymerization degree of 1750 and a polymerization degree of 5 mo/l'%.

The aqueous solution of modified PVA used in Example 6 was obtained by saponifying a copolymer of 3-acrylamide-propyltriethoxysilane and vinyl acetate, and had a silicon-acrylamide unit i of 0.25 mo/I. /%, saponification degree of vinyl acetate unit 97.5 mo/l'%, polymerization degree 17
This is a 6% aqueous solution of modified PVA containing silicon in 50 molecules.

Table 2 Patent Applicant RiRashi Co., Ltd. Agent Patent Attorney Ken Honda

Claims (9)

[Claims] (1) A method for producing base paper for processing, which comprises coating base paper with modified polyvinyl alcohol containing silicon in its molecules. (2) The processing product according to claim 1, which is a saponified product of a copolymer of a modified polyvinyl alcohol vinyl ester containing silicon in the molecule and an olefinic unsaturated monomer containing silicon in the molecule. Manufacturing method of base paper. (3) The olefinically unsaturated monomer containing silicon in the molecule has the following general formula (1) % formula % () [where n is 0 to 4, m is 0 to 2, and R1 is carbon number 1 to 5]
The alkyl group R2 represents an alkoxyl group or an acyloxyl group having 1 to 40 carbon atoms (herein, the alkoxyl group or acyloxy group 1ri may have an oxygen-containing substituent). ] The method for producing a base paper for processing according to claim 2, wherein the vinyl silane is a vinyl silane represented by the following. (4) The olefinically unsaturated monomer containing silicon in the molecule has the following general formula (厘) R'R'm 1 [Here, m is 0 to 2, R1 is an alkyl group having 1 to 5 carbon atoms %R2 is a fullkylene group having 1 to 40 carbon atoms or an acyloxyl group (the alkoxyl group or acyloxyl group may have an oxygen-containing substituent), R3 is a hydrogen atom or a methyl group, R4 is a hydrogen atom or The alkyl group having 1 to 5 carbon atoms, R5, represents a fullylene group having 1 to 5 carbon atoms or a divalent organic residue in which chain return atoms are bonded to each other via oxygen or nitrogen. ] The method for producing processed base paper according to claim 2, which is a monomer represented by the following. (5) The method for producing a base paper for processing according to claim 1, wherein the modified polyvinyl alcohol contains 0.1 to 10 mo)v% of monomer units containing silicon in the molecule. (6) A claim in which base paper is coated with a 0.2 to 20% by weight aqueous solution of modified polyvinyl alcohol containing silicon in the molecule so that the solid content of the modified polyvinyl alcohol is 0.1 to 109/w/. The method for producing base paper for processing according to item 1. (7) The method for producing base paper for processing according to claim 6, wherein a 2 to 10 weight-aqueous solution of modified polyvinyl alcohol containing silicon in the molecule is used. (8) The method for producing base paper for processing according to claim 6, wherein the modified polyvinyl alcohol containing silicon gold in the molecule is coated with a solid content of 0.5 to 597 n/. (9) The method for producing a base paper for processing according to claims 1 to 8, wherein the base paper for processing is a base paper for silicone processing. 60 Production of base paper for processing according to claim 9, wherein the base paper for silicone processing is a base paper for release paper.