JPS6094485A - Releasable treatment having printability - Google Patents

Abstract

PURPOSE:A releasable treatment of ionizing radiation curing type having improved printability especially with aqueous ink, camprising a reaction product of a specific organopolysiloxane, an organic polyisocyanate, and an acrylate compound having an active hydrogen-containing group. CONSTITUTION:(A) An organopolysiloxane shown by the formula [R<1> and R<2> are methyl, ethyl, or (trifluoro)proply; x and y are positive number; m is 0-4; n is 2-3] is reacted with (B) organic polyisocyanate (e.g., tetramethylene diisocyanate, etc.) and (C) an acrylate compound (e.g., hydroxyethyl acrylate, etc.) having one or more active hydrogen-containing groups selected from hydroxyl group, carboxyl group and amino group in an equivalent ratio wherein total equivalents of the compoment A and the component C is approximately equal to an equivalent of the component B to give a reaction product. The desired treatment is obtained from the reaction product.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention has excellent printing properties, particularly with water-based inks such as fountain pens, water-based pens, and printer inks, and has ionizable properties that can provide a release layer with good release properties against adhesives. This invention relates to a radiation-curable releasable treatment agent.

Release agents are widely used as back-treatment agents for pressure-sensitive tape substrates and release agents for pressure-sensitive label separators. As the release agent, polyorcasiloxane, acrylic butyester copolymer, wax, paraffin, etc. have been used or proposed, but the printing properties on the surface of the release layer, especially the printing properties when using water-based ink, have not yet been improved. is insufficient. Therefore, when printing on the backing agent side of a pressure-sensitive tape or the non-adhesive side of the release paper of a pressure-sensitive label,
Although treatment with a release agent that has both printability and releasability is essential, there has been no release agent suitable for such uses.

Furthermore, treated substrates that require such printability are required to have good writability and the feel of normal paper, so they are more likely to be treated with normal high-quality paper than processed paper such as resin-coated paper or film-laminated paper. It is preferable to use paper without a seal, such as paper. However, with such unfilled paper, the release agent has a strong permeability into the base material (conventional solvent or emulsion type release agents cannot provide a good release surface).

The main purpose of the present invention is to solve the above-mentioned problems, to enable easy coating even without a solvent if necessary, to cure quickly by irradiation with ionizing radiation, and to have good peelability. The object of the present invention is to provide a release agent that provides a release agent layer with good printability even for water-based inks.

The ionizing radiation-curable releasable treatment agent of the present invention was developed to achieve the above-mentioned object, and more specifically, it is a reaction product of the following components A), B) and C), It is characterized by having printing suitability.

A) Organopolysiloxane represented by the following general formula (1), where R1 and R2 are each a methyl, ethyl, propyl or trifluoropropyl group, and X and y are each a positive number: m
is an integer of O to 4, nI is an average value in the range of 2 to 3, B) an organic polyisocyanate, and C) at least one hydrobutyric group, carboxyl group, or amino group in one molecule selected from Acrylate compound with active hydrogen-containing group.

That is, in the releasable treatment agent of the present invention, the organopolysiloxane (component A) as the main component has a highly hydrophilic polyether moiety in its structure and an organopolysiloxane moiety that imparts releasability. Since it has both of these properties and is structured in a professional manner, it provides a release agent layer that has both hydrophilicity and release properties. In addition, the organic polyisocyanate component (component B) is effective in providing a release layer with good adhesion to the substrate, curability, and film strength, and the acrylate compound (component C) has ionizable properties. Provides good curing properties against radiation, especially electron beams.

The present invention will be explained in more detail below. In the following description, "%" and "part" indicating composition are based on weight unless otherwise specified.

The organopolysiloxane which is the first main component of the releasable treatment agent of the present invention is represented by the above general formula (1), and the releasability can be controlled by the degree of polymerization y of the organopolysiloxane moiety. Yes, 5-500, especially 10
A range of 500 to 500 is preferably used. If the degree of polymerization y is less than 5, sufficient releasability cannot be obtained, and if it exceeds 500,
Printability slightly decreases. In addition, the polyether part (Cn
H2nO)x has the most important effect on the printability of the resulting release agent layer, and if an alkylene oxide in which n is 4 or more is used, the desired printability cannot be obtained.

n can be a mixture of 2 and 3, but its average value is also between 2 and 3.
3, preferably in the range of 2 to 2.5, particularly in view of providing good printing suitability for water-based inks. The degree of polymerization X of the polyether part is determined in relation to the degree of integration of the organopolysiloxane part 01, mainly so as to provide a good balance between the releasability and printability of the release agent layer obtained. That is, when the value of y/x becomes large and the organopolysiloxane portion becomes relatively large, the peeling force increases but the printing suitability deteriorates, and conversely, when the value of y/x becomes small and the polyether portion becomes small. , the printing suitability increases, but the releasability deteriorates. Therefore, a range of 0.5 to 10 is appropriate for y/x.

On the other hand, the total degree of polymerization of the organopolysiloxane, 2×10y, affects the reactivity with the polyinsyanate. 2x+y
If is too small, a large amount of polyisocyanate will be required, which will have an effect such as poor releasability. On the other hand, if 2x+y is too large, the degree of crosslinking of the release agent decreases, resulting in a significant decrease in film strength or poor curing. Considering this point as well, X is selected from the range of 2 to 100.

The alkylene moiety CmH2mlf located between the organopolysiloxane moiety and the polyether moiety does not particularly need to exist, and in this case C± has the advantage of being able to be produced at low cost. It has the advantage of increased stability.

However, organopolysiloxanes with m0 of 5 or more do not have 41 points in terms of performance, but are disadvantageous in terms of raw material availability, so m0 of 3 or 4 is preferred, with 3 being the most preferable. Girl, N.

Specific examples of organopolysiloxanes include the following.

As the polyisocyanate used in the present invention, aliphatic and aromatic polyisocyanates having two or more incyanate groups in the molecule are used, and specifically, tetramethylene diisocyanate, hexamethylene diisocyanate, 2,4-tolylene diisocyanate, etc. Isocyanate, 2.6-)lylene diisocyanate, 4.4-diphenylmethane diynanate, 1.5-naphthalene diisocyanate,
3.3'-dimethyl 4,4'-diphenylene diisocyanate, inphorone diisocyanate, xylylene diisocyanate, 1,3-bis(incyanatomethyl)cyclohexane, trimethylhexamethylene diisocyanate, triphenylmethane triisocyanate, and etc. can be mentioned. These polyisocyanates may be used in combination.

Next, as the acrylate compound used in the present invention,
Those having at least t(II) active hydrogen-containing groups selected from hydroxyl group, carboxyl group, and amide group in one molecule are used; specifically, hydroxyethyl acrylate, hydroxypropynorea acrylate, hydroxybutyl acrylate, hydroxyethyl methacrylenite,
hydroxydipropyl methacrylate, hydroxybutyl methacrylate 1, y'n-pB roxycyclohexyl acrylate, 5-hydroxycyclooctyl acrylate, 5-hydroxycyclooctyl methacrylate, 2
-Hydroxy-3 phenyloxyprobyl acrylate, etc., and combination products of acrylic butylene, methacrylic acid, or 2-hydroxyethyl acrylate and phthalic anhydride; one activity such as acrylamide, methacrylamide, N-methylol acrylamide, etc. Examples of hydrogen foundation compounds include: Furthermore, the combination of acrylic liquor with jepoxy compounds such as ethylene glycol diglycidyl ether dimethacrylate, diethylene glycol diglycidyl ether dimethacrylate, propylene glycol glycidyl ether cyacrylate, and phthalic amide diglycidyl ester diacrylate; Examples include a reaction product of addition, or a reaction product of glycidyl acrylate or cricidyl methacrylate with a dibasic acid. Specific dibasic acids include itaconebutyric acid, maleic acid, fumarbutyric acid, succinic acid, adipic acid, and terephthalic acid.

The above components A), B) and C) are in such amounts that the total amount of the organopolysiloxane (component A)) and the acrylate compound (component C)) is approximately equal to the equivalent weight of the polyincyanate (component B)). More specifically, within that range, 1 equivalent of component B) to 1 equivalent of component C)
A range of 0.01 to 0.7 equivalents, particularly 0.4 to 0.7 equivalents, is preferable in order to harmonize releasability, printability, coating suitability, curability, cured film properties, etc.

There is some degree of discretion in the method of reacting the above three components.

In the first embodiment, an excess of organic polyinsyanate is reacted with organopolysiloxane to form a prepolymer having free incyanate groups at both ends. At this time, the chain length of the prepolymer can be changed by changing the quantitative ratio of organopolysiloxane and polyisocyanate. Next, an acrylate compound is added to both ends of the prepolymer obtained above. In a second embodiment, an organic polyisocyanate and an acrylate compound are first reacted to produce a compound having a free incyanate group at at least one end, and then further reacted with an organopolysiloxane.

In either embodiment, the above reactions proceed without a catalyst, but a catalyst can be used to accelerate the reaction. Examples of such catalysts include dibutyltin dilaurate, ftrJ-tin octoate, dioctyltin diacetate, morpoline, triethylenediamine, and the like. These catalysts can be used in proportions of lfo, for example 01 to 10%, based on the total weight of the reaction mixture.

The stripping treatment agent of the present invention can use the above reaction product alone or in a mixture with other reactive monomers, solvents, Ir4 materials, fillers, and other additives. . As the reactive monomer, an acrylate monomer having an unsaturated bond, a vinyl or allyl group-containing monomer may be used, for example, in an amount of 5 to 100 parts per 100 parts of the above reaction product.
It is used up to a certain extent.

An example of the use of the releasable treatment agent of the present invention will be explained with reference to the attached drawings. As shown in the cross-sectional view of FIG. The releasable treatment agent obtained as described above is preferably applied at a rate of 0.1 to 5 g/m2 (solid content). If the coating amount is less than 0.1 g/m2, the unevenness on the surface of the substrate will not be completely flattened, and therefore sufficient releasability will not be obtained. Further, even if the coating amount exceeds 5 g/m 2 , no further improvement in releasability can be expected and it becomes uneconomical. The coating method is basically arbitrary, and for example, methods such as roll coating, gravure coating, air knife coating, curtain flow coating, etc. are used. When coating a paper base material without a sealing layer, a release agent layer that hardly penetrates into the base material can be obtained by using a solvent-free releasable treatment agent and hot-melt coating. In terms of coating suitability, it is desirable that the viscosity at the time of coating be io, ooo centistoke or less, and if necessary, the viscosity can be adjusted by adjusting the molecular weight of the above reaction product or diluting it with a reactive monomer as appropriate. I do.

After the releasable treatment agent 2 of the present invention is applied as described above, it is irradiated with ionizing radiation such as electron beams, gamma rays, X-rays, and short wavelength ultraviolet rays to be cured. For example, for electron beams,
It is emitted from various electron beam accelerators such as Kotscroft Walton type, bump graph type, resonant transformer type, linear type, dynamidron type, high frequency type, etc., and the energy range is 5O-1000KeV, preferably 1゜O~300keV. An electron beam with . The irradiation dose is 05~1゜M r
A value of about d is appropriate.

Next, as shown in FIG. 2, on the release agent layer 2a obtained by curing, a printing pattern 3 using ordinary oil-based or water-based ink is applied as necessary, an adhesive layer 4 is formed on the back side, and perforations are formed. 5 and winding it up, a label roll as shown in FIG. 3 is obtained. Further, as shown in FIG. 4, it is also possible to obtain a laminate of forms 6 with one end fixed with an adhesive 4. The label or form thus obtained has the feature that writing can be easily written on the margin provided by the surface of the release agent 2a using not only oil-based ink but also water-based ink.

As described above, according to the present invention, it is made of a reaction product of an organopolysiloxane having a polypreter moiety, an organic polyisocyanate, and an acrylate compound having an active hydrogen-containing group, and is easily made into a solvent-free type. It is easy to apply even to paper without a stopper layer, and is rapidly cured by irradiation with ionizing radiation, providing a release agent layer with good releasability and good printability even with water-based inks. A strippable treatment agent is provided.

The present invention will be explained in more detail below with reference to Examples.

Tolylene diisocyanate and 10% ethyl acetate were added to a mixture of tolylene diisocyanate and hydroxyethyl acrylate in an equal molar amount to the tolylene diisocyanate, and the temperature of the reaction system was set to 40~40°C.
The mixture was added dropwise while maintaining the temperature at 60°C. After the addition was completed, stirring was continued for 2 hours to obtain an adduct of tolylene diisocyanate and hydroxyethyl acrylate.

The adduct obtained above was added in equimolar amounts to the following organopolysiloxane having a polyether bond.

Di-n-butyltin diurarate was added as a catalyst to this mixture in an amount of about 0.1% of the total amount, and stirring was continued for 3 hours while maintaining the mixture at 50 to 60°C to cause a reaction.

The stripping treatment agent of the present invention obtained by adding 0.01% of hydroquinone to the reaction product obtained above,
High-quality paper (55 kg manufactured by Daishowa Paper) was coated with a coating amount of 0.5 g/m2 using a roll coating method, and then an electron beam irradiation device (manufactured by ESI, Electro Curtain CB200150/30) was used. It was cured by irradiation with an electron beam under the conditions of an accelerating voltage of 175 KV and an irradiation dose of I M r ad. Further, as shown in FIG. 2, an acrylic pressure-sensitive adhesive (BPS2411 manufactured by Toyo Ink) was applied in stripes to the surface opposite to the surface to which the release agent was applied, in an amount of 10 g, 7 m.sup.2.

After doing this, printing was performed on the peeled surface using an ink containing a polyether binder as a main component using a printer, and the print was clear and the peeling force against the adhesive (180' peeling, 30 cm 7 A good result was obtained with a tensile speed of 10 g/cm. Also 1
Although unwinding was carried out at a tensile speed of 00 m/min, no damage to the base material such as paper cracking occurred.

While keeping a mixture of tolylene diisocyanate and 10% of it with 9 ethyl acetate at 50 to 60°C, add about 0% of the total amount to the following silicone at a ratio of 0.5 mol to 1 mol of tolylene diisocyanate.゜1% catalyst dilauric acid di-n-
Butyltin was added dropwise.

After dropping, stirring was continued for 3 hours to obtain a prepolymer having incyanate groups at both ends.Next, 2 mol of hydroxyethyl acrylate was added dropwise to 1 mol of the above prepolymer and kept at 50 to 60°C. While
Stirring was continued for 3 hours. 0.01% of hydroquinone was added to the total amount of the reaction product thus obtained.

When the obtained release agent was coated in the same manner as in Example 1 and the writability and releasability were evaluated, good results were obtained.

[Brief explanation of drawings]

FIGS. 1 and 2 are schematic cross-sectional views in the thickness direction of a base material showing the process of applying the releasable treatment agent of the present invention to the base material, and FIGS. 3 and 4 illustrate the releasable treatment obtained, respectively. 1 is a conceptual side view of a product having a surface.Base material 2...Releasable treatment agent layer (2a...its cured state) 3
... Normal printing pattern 4 ... Adhesive layer 5 ... Perforation 6 ... Form

Claims (1)

[Scope of Claims] An ionizing radiation-curable releasable processing agent characterized by being a reaction product of the following components A), B) and C) and having printing suitability. A) Organopolysiloxane-C4H21IIO (Cn H2T, 0) × -H fist represented by the following general formula (1) (1) However, here, Hl and H2 are methyl, ethyl, propyl, or trifluoropropyl, respectively. The group, x, y are each positive numbers; m
is an integer from 0 to 4, n is an average value in the range from 2 to 3, B) an organic polyisocyanate, and r) IQ production tj /I) fP/b L + Jltl M −
An acrylate compound having an active hydrogen-containing group selected from a carboxyl group and an amino group.