JPS61143482A - Releasable sheet having writing suitability - Google Patents

Abstract

PURPOSE:To obtain a releasable sheet having the balanced releasing property and the writing suitability in the releasing layer itself, by coating the surface of a substrate with a releasing layer containing a vinyl polymer, etc. containing organopolysiloxane unit bonded to the polymer in the form of block. CONSTITUTION:The objective releasing sheet can be produced by coating at least a surface of a substrate sheet with e.g. a coating agent containing (A) a vinyl polymer bonded with an organopolysiloane unit in the from of block or grafted with said siloxane unit and/or (B) a derivative prepared by modifying the polymer A, thereby forming a releasing layer to the surface. The polymer A can be produced by polymerizing the compound of formula (R<1> is bivalent hydrocarbon group; R<2> is univalent hydrocarbon group; l is 0-2) with a radically polymerizable monomer (e.g. methyl methacrylate), and the polymer B is produced e.g. by adding glycidyl methacrylate to the carboxyl group of the polymer A. The polymers can be crosslinked with ionizing radiation.

Description

[Detailed description of the invention] [Industrial application field] The present invention is concerned with printing suitability, particularly fountain pens and water-based pens.

The present invention relates to a sheet that is suitable for printing with water-based ink such as printer ink and has removability against adhesives, that is, a removable notebook that is suitable for writing.

[Conventional technology]

Mold release agents are widely used as back treatment agents for pressure-sensitive tape substrates and separator treatment agents for pressure-sensitive labels.For example, polyorganosiloxanes, acrylic acid ester copolymers, Fuchs, paraffin, etc. It's being used.

[Problem that the invention seeks to solve]

By the way, in the mold release layer formed using the conventional mold release agents, those having excellent properties in releasability are poor in writability, and those having writing suitability are poor in releasability, and the surface of the mold release layer is At present, no material has been found that is fully satisfactory in its printing suitability, particularly its printing suitability with water-based inks.

[Means to solve the problem]

In the releasable sheet having writing suitability of the present invention, the releasable layer comprises a vinyl polymer [A] in which organopolysiloxane units are bonded in a block or graft form, or the polymer [A]. The releasable sheet of the present invention, which is substantially composed of a modified derivative [B] or a combination of both types (A) and CB), and which has writability and has the above-mentioned structure, has a good releasability. Since this layer has characteristics, this releasable layer will be explained below.

As described above, the releasable layer in the releasable sheet having writing suitability of the present invention is made of a vinyl polymer [A] in which organopolysiloxane units are bonded in a block or graft form, or the polymer (A). ) modified derivative [
B], or a combination of both types (A) and CB), and the vinyl polymer [
A method of forming a releasable layer by coating at least one side of a sheet-like base material with a coating agent containing A), etc., and drying the coating agent, and a method in which the vinyl polymer (A), etc. is formed by heating etc. coating at least one side of a sheet-like substrate with a coating agent containing a composition;
Next, by performing a post-treatment such as heating, the above-mentioned vinyl polymer (A) etc. are reacted and produced on the sheet-like base material,
There is a method of forming a releasable layer.

One method for obtaining a vinyl polymer (A) in which organopolysiloxane units are bonded in a block or grafted manner is to use an organopolysiloxane having at least one siloxane unit represented by the general formula in the molecule. This is a method of polymerizing a radically polymerizable monomer and a radically polymerizable monomer.

As mentioned above, the organopolysiloxa/ used in obtaining the vinyl polymer (A) by this method has the above general formula (1) or general formula (2) as the 7 siloxa units bonded to the silicon atom. Any material may be used as long as it has at least one siloxane unit represented by the above, and there are no restrictions on its molecular structure or the bonding position of the siloxane unit represented by the general formula (1) or (2) above. The molecular structure may be either a linear structure or a 9-molecular chain structure. In addition, this organopolysiloxane has a molecular chain terminal such as a triorganosilyl group such as a trimethylsilyl group, a hydroxydiorganosilyl group such as a hyProxydimethylsilyl group, or a mercaptoglopyrudimethylsilyl group. Examples of the organic group bonded to the silicon atom other than the mercanotoalkyl diol represented by the general formula (2) include a methyl group, an ethyl group, a propyl group, a fluoropropyl group, etc. An organopolysiloxane having the following is preferably used. Furthermore, it goes without saying that this organopolysiloxane has no restrictions on the arrangement order of the siloxane units represented by the above general formula (1) or general formula (2) and other organosiloxane units; All units of the siloxane may be represented by the above general formula (1) or general formula (2).

The other component, the radically polymerizable monomer, used in the above method to obtain the vinyl polymer (A) has the following formula: R5 is hydrogen or a methyl group, R7 is a) alkyl alkyl group, hydrogen, alkyl group having a hydroxyl group, alkyl group having a carboxyl group, alkyl group having an epoxy group, an alkyl group having an aziridinyl group, an alkyl group having an amino group, an alkyl group having an incyanate group or sul (an alkyl group having a 7-one group), such as methyl methacrylate, methyl acrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, butyl acrylate,
Butyl methacrylate, inbutyl acrylate, inbutyl methacrylate, t-butyl acrylate, t-
Butyl methacrylate, inamyl acrylate, isoamyl methacrylate, cyclohexyl acrylate,
Cyclohexyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, N-methylolacrylamide r12-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate,
2-Hydroxyzorobyl acrylate, 2-hydroxyprogyl methacrylate, 2-hydroxybutyl acrylate, 2-hydroxybutyl methacrylate, 2-hydroquine-3-phenoxypropyl methacrylate, 2
-Hydroxy-3-phenoxyzoroglyacrylate-
Acrylic acid, methacrylic acid, acryloyloxyethyl monosuccinate, grindyl methacrylate, 2-aziridinylethyl methacrylate, allyl 2-aziridinylzolopionate, acrylamide, methacrylamide P1 diacetone acrylamide, dimethylaminoethyl methacrylate,
Diisocyanates such as diethylaminoethyl methacrylate, 2-acrylamido-2-methylpropanesulfonic acid, and equimolar adducts of 2.4-toluene diincyanate and 2-hydroxyethyl acrylate with radically polymerizable monomers having active hydrogen. Adducts, vinyl esters of fatty acids such as vinyl acetate and vinyl propionate, styrene, and α-methylstyrene.

Monomers such as vinyltoluene, maleic anhydride, itaconic acid, and mixtures of these monomers can be used.

Another method for obtaining the vinyl polymer (A) in which organopolysiloxane units are bonded in block or graft form is to add the above-mentioned radically polymerizable monomer to mercaptoethanol, which is added as necessary. , mercazotozologionic acid.

Polymerization is performed in the presence of a polymerization degree regulator such as dodenlumel butane to form hydroxyl and carboxyl groups.

After obtaining a vinyl polymer having functional groups such as Epo, Kin group, Incyanate group, and amine group, the vinyl polymer having this functional group and methyloxy group, hydroxyl group, carboxyl group, Ami7 group, Epokin group, etc. In this method, a bonding reaction with a reactive organopolysiloxane having a group, a mercazoto group, etc. is carried out, if necessary, in the presence of a polyvalent incyanate compound, a polyvalent epoxy compound, etc.

In addition, a vinyl polymer (
In the case where the bonding reaction between the two is carried out in a post-treatment such as heating, the formation of the release layer consisting essentially of A) is performed by reacting with a vinyl polymer having a functional group. This can be carried out by coating at least one side of a sheet-like base material with a coating agent containing a synthetic organopolysiloxane, and then subjecting it to a post-treatment process such as heating.

In addition, as the radically polymerizable monomer used when obtaining the vinyl polymer (A), in particular, hydrophilic groups such as a water curtain group, a carboxyl group, an epoxy group, an aziridinyl group, an amino group, a sulfone group, etc. When using a monomer having the following properties, it is possible to obtain a releasable layer having better printability.

In the releasable sheet having writing suitability of the present invention, the vinyl polymer (
There is no particular restriction on the ratio of the above-mentioned organopolysiloxane and the above-mentioned radically polymerizable monomer in A). It has been confirmed that a mold release layer with sufficient mold release performance and writability can be obtained by changing the ratio of the organopolysiloxane component and the radically polymerizable monomer component. The degree of mold release performance and the degree of writability provided in the adhesive layer can be adjusted as desired.

Each polymerization to obtain the vinyl polymer (A) can be carried out using conventionally known polymerization methods, such as benzoyl peroxide, t-butyl hydroperoxide, cumene hydroperoxide,
Solution polymerization, suspension polymerization, emulsion polymerization, Sakaiaki polymerization, etc. using a polymerization initiator such as α, α-azoshiisobutyroni) IJ can be used.

In addition, when a monomer having a functional group such as a hydroxyl group, a carboxyl group, an epoxy group, an aziridinyl group, or an isocyanate group is used as a component of the radically polymerizable monomer when forming the vinyl polymer (A). It is possible to heat-cure the mold release layer using the functional groups in the vinyl polymer (A) that substantially constitutes the mold release layer, and to improve heat resistance and solvent resistance. , it can be made into a releasable layer having excellent properties such as plasticizer resistance.

Incidentally, the formation of the heat-cured release layer includes (1) applying a coating agent containing the heat-curable vinyl polymer (A) having the functional group to a sheet-like base material and then heating it; (2) Applying a coating agent containing two or more types of thermosetting polymers to a sheet-like base material and then heating (3)
) Thermosetting crosslinking agent in the coating agent, e.g.? Lyisocyanate group compounds, polyepoxy compounds, polyaziridinyl group compounds,? (4) A coating agent containing various catalysts such as dibutyltin laurylate, xyridine, etc., added as necessary to the coating agent, is applied to the sheet-like substrate and then cured. Methods such as applying and then curing can be used.

Furthermore, the derivative (B) obtained by modifying the vinyl polymer (A) contains, for example, a hydroxyl group or a carboxyl group as at least one component of the radically polymerizable monomer used to obtain the vinyl polymer (A). .

Using a monomer having a functional group selected from an epoxy group, an aziridinyl group, an incyanate group, etc., the resulting vinyl polymer [A] is modified by introducing a third component into the functional group. However, as a representative example of this derivative (B), a radically polymerizable unsaturated group is introduced into the carboxyl group of the vinyl polymer (A) by, for example, addition reaction with glycidyl methacrylate. Derivatives [
B], a releasable layer substantially composed of a polymer having a crosslinked structure introduced by irradiation with ionizing radiation can be obtained, and has good heat resistance, solvent resistance, and plasticizer resistance. It can be made into a releasable layer that exhibits excellent properties.

The method for introducing a radically polymerizable unsaturated group into the vinyl polymer (A) is as follows.

(1) When the functional group is a hydroxyl group, a monomer having a carboxyl group such as acrylic acid or methacrylic acid is subjected to a condensation reaction. (2) When the functional group is a carboxyl group or a sulfone group, a monomer having a hydroxyl group is subjected to a condensation reaction. (3) The functional group is an epoxy group or an incyanate group.

Alternatively, in the case of an aziridinyl group, conduct an addition reaction with a monomer having a hydroxyl group or a monomer having a carboxyl group (4) If the functional group is a hydroxyl group or a carboxyl group, use a monomer having an epoxy group or a monomer having an azirizonyl group Furthermore, a method is used in which an equimolar adduct of a diisocyanate compound and an acrylic acid ester monomer having a hydroxyl group is subjected to an addition reaction, but the reaction is carried out in the presence of a trace amount of a polymerization inhibitor such as hydroquinone. It is preferable to carry out this process while supplying dry air.

Further, the derivative C into which the radically polymerizable unsaturated group is introduced
In the case of the release layer according to B), ethylene glycol diacrylate, ethylene glycol dimethacrylate, polyethylene glycol diacrylate, -lyethylene is added to the coating agent in order to improve the crosslinking density of the derivative CB) by irradiation with ionizing radiation. Glycol dimethacrylate, hexanediol diacrylate, hexanediol dimethacrylate, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, trimethylolpropane diacrylate, trimethylolpropane dimethacrylate, pentaerythritol tetraacrylate, pentaerythritol tetramethacrylate, pentaerythritol Triacrylate, pentaerythritol trimethacrylate, dipentaerythritol hexaacrylate, dipentaerythritol hexamethacrylate, ethylene glycol diglycidyl ether diacrylate, ethylene glycol
Cole diglycidyl ether dimethacrylate, polyethylene glycol diglycidyl ether diacrylate, polyethylene glycol diglycidyl ether dimethacrylate, propylene glycol diglycidyl ether diacrylate, propylene glycol diglycidyl ether dimethacrylate, polypropylene glycol diglycidyl ether diacrylate, polyzoro 0.1 to 100% by weight of pyrene glycol glycyl ether dimethacrylate, nrubitol tetraglycidyl ether tetraacrylate, nrbitol tetraglycidyl ether tetramethacrylate, etc., based on the derivative CB).
It is preferable to mix it to some extent.

Methods for introducing a crosslinked structure into the derivative (B) include a method of irradiating with ionizing radiation and a method of using a radical polymerization initiator, but from the viewpoint of completing curing in a short time, The preferred method is As the ionizing radiation, electron beams, ultraviolet rays, gamma rays, etc. can be used, and in the case of electron beams and gamma rays, about 1 to 20 Mrad is preferable, and in the case of ultraviolet irradiation, benzoquinone, bency/ , benzoin ethers such as benzoin methyl ether, I-rhodanated acetophenones,
It is preferable to use a material that generates radicals when irradiated with ultraviolet rays, such as Biatil. In addition, in the method using a radical polymerization initiator, a polymerization initiator such as various peroxides such as benzoyl peroxide or a,a-azobisisobutyronitrile is added to the derivative CB) at a ratio of 0.1 to 1. It is sufficient to add about % by weight and heat above the decomposition temperature.

The releasable sheet having writing suitability of the present invention, that is, the releasable layer is a vinyl polymer [A] in which organopolysiloxane units are bonded in a block shape or a graft shape,
or said polymer 1. A, a modified derivative [B],
Alternatively, a releasable sheet substantially composed of a combination of these two types (A) and CB) has a vinyl polymer (A), a vinyl polymer (A),
Or a derivative obtained by modifying the polymer (A) [
B], or a coating agent containing both of these, or a coating agent containing a component that produces the polymer [A) etc. by post-treatment such as heating, and after drying or heating as necessary. It can be easily obtained by processing. The coating agent used to form the releasable layer is coated with a suitable solvent, if necessary, to adjust the coating suitability. In some cases, the reaction product solution is used as it is as a coating agent. Also,
In order to improve storage stability, it is preferable to add a polymerization inhibitor such as hydroquinone or hydroquinone monomethyl ether to this coating agent.

Incidentally, the coating agent may be the polymer [A) or the derivative CB.
), or each component capable of producing polymer (A) or derivative CB), and if necessary, additives such as radically polymerizable monomers and sensitizers. Of course. However, in the releasable sheet having writing suitability of the present invention, the releasable layer may contain the vinyl polymer (A'l) or a derivative obtained by modifying the polymer (A) + [3 ], or a mixture of these (A),
(:B), the above-mentioned coating agent may contain cellulose resins such as ethyl cellulose and nitrocellulose, polyester resins, &IJ urethane resins, rosin, etc., as necessary. Rubber resins such as ester resins and cyclized rubbers, polymers such as chlorinated polyolefin resins, and coloring agents such as pigments and dyes may be added as appropriate.

The method of forming a releasable layer on the upper surface of a sheet-like base material using the above-mentioned coating agent is the same as the conventional application method of a general coating agent, such as a roll coating method, a gravure coating method, a screen coating method, a fountain coating method, etc. By coating methods such as coating method, sheet-like substrates such as polyester film, polyamide film, cellophane film, acetate-1-film, etc. J 7' Robyren film 1 paper.

A solid content of 0.1 to 0.1 on the surface of a sheet-like base material such as a single sheet such as metal foil or a laminated sheet of two or more types as required.
4! /rr? It is coated to a certain degree and dried to form a releasable layer as a surface layer.

In addition, the above-mentioned polymer (A
) and derivative CB), after the solvent and the like in the coating agent layer formed on the sheet-like base material surface is dried, a predetermined thermosetting treatment or ionizing radiation irradiation treatment is performed.

〔Example〕

Hereinafter, the specific structure of the releasable sheet having writing suitability of the present invention will be explained with reference to manufacturing examples, and the properties of the obtained releasable sheet will also be explained.

Example 1 The following composition (1) was sealed in a reaction vessel equipped with a heating and stirring device, and refluxed for 10 hours to perform a polymerization reaction to obtain a coating material (A).

Composition (1) Methyl methacrylate 200 parts by weight 2-
Hydroxyethyl methacrylate 200 parts by weight Dimethylpolyloxane 200 parts by weight Methyl ethyl ketone 500 parts by weight Toluene
500 parts by weight α,α'-azobisisobutyronitrile 1 part by weight Next, the above-mentioned sheet-like base material consisting of a composite sheet having a 15 μm thick polyethylene layer on one side of graft paper which has been subjected to corona discharge treatment. The above-mentioned coating material (A) was uniformly applied to the entire surface of the polyethylene layer using a #40 μm gravure solid plate, and then the solvent was evaporated through a drying hood at 80°C, and the applied coating layer was dry to the touch. A releasable sheet [a] which is an example product of the present invention, in which a releasable layer was formed by
I got it.

The obtained releasable sheet [a] and an adhesive tape in which an acrylic adhesive [Olipine BPS5127: manufactured by Toyo I/Ki ■] is coated on the surface of a polyester film at a rate of 25 r/m'' are used for releasability. V-) Laminate so that the release layer of (a) and the adhesive surface of adhesive take 0 are in contact with each other, and
After a period of time had elapsed, the force required to separate the two was measured and found to be 120 fI/25+mn width. For comparison, the adhesive tape 0 was pressed against a polyethylene quill rem, and the force required to separate the two was similarly measured and found to be 1340 j'/25 m width.

Furthermore, when writing was done on the surface of the releasable layer of (a) with a commercially available water-based pen (trade name: Pentel felt-tip pen), there was no ink repellency, and it had good writing aptitude.

Example 2 After refluxing the following composition (2) in a reaction vessel for 10 hours to perform a polymerization reaction, 1 part by weight of benzoquinone was added,
The reaction was stopped.

Composition (2) Dimethylaminoethyl methacrylate 110 parts by weight 2-hydroxyethyl methacrylate 39
M m part dimethylpolysiloxane (X2)
30 parts by weight Bency peroxide 10.5 parts by weight Ethyl acetate 300 parts Next, 90 parts by weight of an equimolar adduct of 2-hydroxyethyl acrylate and 2,4-)luene diisocyanate and 300 parts by weight of methyl ethyl ketone were added to the reaction product solution. parts by weight were added, and the mixture was reacted at 80° C. for 5 hours while blowing dry air.

20 parts by weight of an ultraviolet sensitizer [Irgacure 184: manufactured by Ciba Ga Iggy] and 10 parts by weight of trimethylolpropane triacrylate were added to the reaction product solution obtained in this way to form an ultraviolet curable coating material (B). Obtained.

This coating material (B) was applied to the same sheet-like base material as that used in Example 1 at a coating rate of 0.1j! (solid content)/rr? Coated at a ratio of
The sheet was cured by passing under an ultraviolet lamp 1Ocrn having an output of W/crn at a running speed of 10 m/min to obtain a releasable sheet (b) which is an example of the present invention.

When the force required for peeling was measured in the same manner as in Example 1 (a), the force required for peeling was 340F/25+++s+ width, and it was difficult to write with a water-based pen on the releasable layer. The properties were also good.

Example 3 The following composition (31) was refluxed for 10 hours in a reaction vessel to perform a polymerization reaction.

Composition (3) Methyl methacrylate 100 parts by weight Acrylic acid 36 parts by weight Dimethylaminoethyl methacrylate 152 parts by weight Dimethylpolysiloxane 100 parts by weight Toluene 400 parts by weight Methyl ethyl ketone 100 Parts by weight α,α-azobisisobutyronitrile 0 After adding 1 part by weight of hydroquinone monomethyl ether to the obtained reaction product solution, 70 parts by weight of glycidyl methacrylate was added, and the mixture was heated to 9o~ioo'c while blowing dry air.
for 8 hours to form an ionizing radiation-curable coating material [C
) is a mouse.

The coating material (C) was coated with high-quality paper [Daishowa Paper ■Near: 55
kg] by roll coating method (solid content)
/W? It is coated at a ratio of
Manufactured by ESI: Electrocarte 7 CB200150/
30), acceleration voltage 175KV, irradiation dose IM
A releasable layer was formed by irradiating and curing with an electron beam under rad conditions.

After that, apply acrylic adhesive [manufactured by Toyo Ink ■: BPS5127] for 10 minutes to the opposite side of the high-quality paper. i
/m'' in a striped manner to obtain a releasable sheet [C] which is an example of the present invention.

When printing was performed on the surface of the releasable layer of the releasable sheet (C) thus obtained using a printer using an ink containing a polyether binder as a main component, clear prints were obtained. Furthermore, the peeling force (186 peeling, pulling speed of 30 crn/min) against the adhesive on the back side of the releasing layer was 10.41.

Furthermore, although the releasable sheet [C] was rewound at a pulling speed of 100 m/min, no damage to the base material such as paper flaking occurred.

Example 4 The following composition (4) was refluxed for 10 hours in a reaction vessel to perform a polymerization reaction.

Composition (4) Methyl methacrylate 300 M ff
r'6152-hydroxyethyl methacrylate
200 parts by weight α,a-azobisisobutyronitrile
1 part by weight ethyl acetate 100
0 parts by weight of 100 parts by weight of the obtained reaction product solution was added γ-hyroxyzologyldimethylsilicate at both ends of the molecular chain.

Viscosity 400 centistokes (25°
C) 30 parts by weight of dimethylpolysiloxane and tolylene diisocyanate adduct [manufactured by Nippon Polyurethane]
15 parts by weight of an organic incyanate compound (Coronate Lj) was added to obtain a coating strip (DI).

The obtained coating material CD) was applied to a polyester film. P
(A releasable layer is formed by coating at a solid content of 1/rr?, drying, and curing in an atmosphere of 40°C for 72 hours, and a releasable sheet is an example product of the present invention) (d ) was obtained.

The peeling performance of the obtained releasable sheet (d) was measured in the same manner as in Example 1 (releasable sheet) (a), and the force required for peeling was determined to be 230ji'/25T+.
+m width, and the polyester film used for comparison was 1420/25 mm wide.

Further, when the releasable layer of the releasable sheet 1-(d) was written with water-based ink, the writing properties on the face were good.

[Action and effect]

The releasable sheet having writing suitability of the present invention has a releasable layer in which the releasable layer is made of a vinyl polymer [A] in which organoporin loxane units are bonded in a block or graft manner, or Derivatives obtained by modifying the combination (A) [
B], or a combination of both types (A) and (B), in which the release layer itself also has writing properties, and the release layer is substantially composed of (A) and (B). By appropriately selecting the constituent components of the above-mentioned vinyl polymer [A], etc., the balance between the release performance and writing suitability of the release layer can be varied widely, and the properties can be adjusted to meet needs. It has the effect of being able to obtain a wide range of products.

Claims (3)

[Claims] (1) A releasable sheet comprising a sheet-like base material and a releasable layer formed on at least one side of the sheet-like base material, in which the releasable layer has organopolysiloxane units in the form of blocks or grafts. Substantially composed of a vinyl polymer [A] that is bonded in a shape, or a modified derivative of the polymer [A] [B], or both of these polymers [A] and [B]. 1. A releasable sheet having writing aptitude. (2) The ratio of organopolysiloxane and vinyl polymer in the vinyl polymer [A] or the modified derivative of the polymer [A] [B] is 100:1,000,000 to 1 (polymerization ratio) A releasable sheet having writability as claimed in claim 1. (3) Vinyl polymer [A], a modified derivative of the polymer [A] [B], or both of these polymers [
2. A removable sheet suitable for writing according to claim 1, wherein A] and [B] are polymers having a crosslinked structure.