JP2008169322A - Adhesive material and releasing sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an adhesive material having good slipperiness of a releasing sheet and exhibiting moderate releasing force in low-speed and high-speed releasing. <P>SOLUTION: The adhesive material 10 is produced by pasting an adhesive sheet 23 having an adhesive layer 22 on one surface of an adhesive sheet substrate 21 to a releasing sheet 13 having a releasing agent layer 12 on one surface of a releasing sheet substrate 11 in a state to contact the releasing agent layer 12 with the adhesive layer 22. The releasing agent layer 12 is formed by coating and curing an addition-reactive solventless releasing agent composition containing a low-molecular organopolysiloxane having at least two alkenyl groups in one molecule and having a mass-average molecular weight of 1,000-20,000 and a high-molecular straight-chain organopolysiloxane having a mass-average molecular weight of 50,000-500,000. The adhesive layer 22 is composed mainly of an acrylic emulsion adhesive. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a pressure-sensitive adhesive body and a release sheet used for printer labels for dry electrophotographic systems.

  The pressure-sensitive adhesive used for printer labels for dry electrophotographic systems is composed of a pressure-sensitive adhesive sheet attached to a release sheet, part of the pressure-sensitive adhesive sheet is removed as an ear, and the remaining base material of the pressure-sensitive adhesive sheet Is used as a label for printing. The pressure-sensitive adhesive body used in such applications is required to have high slipperiness in the release sheet in order to improve running performance in the printer and prevent paper jamming.

  In recent years, pressure-sensitive adhesives are being demanded to reduce the burden on the environment. Solvent-free silicone is being used as a release agent, and the use of emulsion-type adhesives is being studied.

  Patent Document 1 discloses a solventless release agent composition for improving the slipperiness of the release sheet. Here, in the release agent composition containing a low molecular organopolysiloxane having an alkenyl group at the molecular chain terminal and a high molecular organopolysiloxane, the number of alkenyl groups of the low molecular organopolysiloxane per molecule is more than 2. This reduces the slipperiness of the release sheet.

Patent Document 2 discloses a solvent-free release agent composition based on a low-viscosity diorganopolysiloxane having a branched structure and having an alkenyl group only at the end of the molecular chain. The structure which can provide slipperiness to a peeling sheet by adding the high viscosity diorganopolysiloxane which has this is disclosed.
JP 2002-356667 A JP 2006-152265 A

  However, in Patent Document 1, the slipperiness of the release sheet is improved, but since the release force during low-speed release is set to be small, the label portion is easily turned from the release sheet during printing or label transport, Troubles such as defects are likely to occur. Moreover, since the peeling force at the time of high-speed peeling is set to be large, there is a problem that if the pressure-sensitive adhesive sheet is peeled off at high speed, the pressure-sensitive adhesive sheet is broken and cannot be removed at high speed. Even in Patent Document 2, the speed dependency of the peeling force is not taken into consideration, and the same problem may occur.

  Therefore, the present invention has been made in view of the above problems, and improves the slipperiness of the release sheet, keeps the release force at a low speed release at a predetermined level, and suppresses the release force at a high speed release. An object of the present invention is to provide a pressure-sensitive adhesive body using a solventless type release agent composition that can be used.

  The pressure-sensitive adhesive body according to the present invention has a pressure-sensitive adhesive sheet provided with a pressure-sensitive adhesive layer on one surface of a pressure-sensitive adhesive sheet base material, and a pressure-sensitive adhesive sheet provided on one surface of the pressure-sensitive adhesive sheet base material. Low molecular weight organopolysiloxane in which the release agent layer has at least two alkenyl groups in one molecule having a mass average molecular weight of 1000 to 20,000 in the pressure-sensitive adhesive body constituted so as to be in contact with the pressure-sensitive adhesive layer And an addition-reaction type solventless release agent composition comprising a high-molecular-weight linear organopolysiloxane having a mass average molecular weight of 50,000 to 500,000.

  In order to express sufficient slipperiness, the polymer linear organopolysiloxane preferably has a small number of alkenyl groups, preferably has an alkenyl group only at the molecular end or no alkenyl group. . When it has an alkenyl group only at the molecular end, for example, each molecular end in one molecule has 1 to 3 alkenyl groups. The viscosity of the release agent composition before curing is, for example, 50 to 3000 mPa · s. Further, for example, the dynamic friction coefficient between the release agent layer surface of the release sheet and polyethylene terephthalate is 0.1 to 0.6 in the measurement method according to JIS P8147.

  Moreover, it is preferable that the said adhesive layer is comprised with an acryl-type emulsion adhesive, and an acryl-type emulsion adhesive is an acrylate-type copolymer containing 0.3-5.0 mass% of functional group containing monomers. It is preferable that it is an emulsion adhesive containing. By the combination of the acrylic emulsion pressure-sensitive adhesive and the release agent composition, it is possible to keep the release force at a low speed release at a predetermined level and sufficiently suppress the release force at a high speed release. Moreover, according to such a structure, since it becomes unnecessary to use an organic solvent for a release agent layer and an adhesive layer, an environmental load can be reduced.

  In this invention, the peeling force with respect to the adhesive sheet of a peeling sheet measured by the conditions of peeling speed 0.3m / min and peeling direction 180 degrees in the environment of temperature 23 degreeC and humidity 50% is 50-1500mN /. It is preferable that it is 50 mm. Moreover, the peeling force with respect to the adhesive sheet of a peeling sheet measured by the conditions of a peeling speed of 100 m / min and a peeling direction of 180 degrees in an environment of a temperature of 23 ° C. and a humidity of 50% is 100 to 3000 mN / 50 mm. preferable.

  In the present invention, feed hole portions for feeding the adhesive body in the longitudinal direction are formed at both ends in the width direction of the release sheet, and the adhesive sheet is partially removed from the release sheet as an ear portion. The portion left on the release sheet is preferably used as a label portion for printing.

  The release sheet according to the present invention is a release sheet having a release agent layer on one surface of a release sheet substrate, wherein the release agent layer has at least two alkenyl groups in one molecule having a mass average molecular weight of 1000 to 20,000. An addition reaction type solventless release agent composition comprising a low molecular weight organopolysiloxane having a group and a high molecular weight linear organopolysiloxane having a mass average molecular weight of 50,000 to 500,000 is formed by curing. It is characterized by that.

  In the present invention, by using a release agent composition in which a high molecular weight linear organopolysiloxane is added to a low molecular weight organopolysiloxane for a release sheet, the release sheet has good slipperiness, and low speed and high speed release. Sometimes a pressure-sensitive adhesive body having an appropriate peeling force can be obtained. Also, this release sheet is combined with an emulsion-type pressure-sensitive adhesive, particularly a pressure-sensitive adhesive sheet using an acrylic emulsion pressure-sensitive adhesive containing an acrylic ester-based copolymer containing 0.3 to 5.0% by mass of a functional group-containing monomer. In this way, it is possible to obtain a pressure-sensitive adhesive body having a particularly appropriate peeling force. Furthermore, by using a solvent-free release agent and an emulsion pressure-sensitive adhesive, it is possible to provide a pressure-sensitive adhesive body with little environmental load.

Hereinafter, the present invention will be described in more detail using embodiments.
FIG. 1 is a schematic cross-sectional view showing an adhesive body according to an embodiment of the present invention. The pressure-sensitive adhesive body 10 is peeled off from a pressure-sensitive adhesive sheet 23 having a pressure-sensitive adhesive layer 22 on one surface of a pressure-sensitive adhesive sheet base material 21 and a pressure-sensitive adhesive sheet 23 having a pressure-sensitive adhesive layer 22 on one surface of the pressure-sensitive adhesive sheet base material 21. The adhesive layer 12 is adhered and configured so as to be in contact with the adhesive layer 22.

  FIG. 2 is an example in which the adhesive body 10 is applied to a printer label. The pressure-sensitive adhesive sheet 23 of the pressure-sensitive adhesive body 10 is cut and cut from the surface side of the base material 21 (see FIG. 1) so as to surround a predetermined portion, whereby the pressure-sensitive adhesive sheet 23 is cut. A label portion 42 surrounded by 41 and an ear portion 43 other than the label portion 42 are included. The ear part 43 is peeled off and removed from the release sheet 13, the label part 42 is left on the release sheet 13, and the adhesive body 10 from which the label part 42 is left is used as a printer label.

  The pressure-sensitive adhesive sheet 23 has at least both ends in the width direction (left and right direction in FIG. 2) removed as ears 43 and the pressure-sensitive adhesive sheet 23 has been removed. Innumerable feed holes 44 are formed along the vertical direction in FIG. The printer label is transported in the longitudinal direction of the label when the feed hole 44 is fitted into, for example, a feed pin (not shown) inside the printer, and the feed pin moves, and the label portion is printed by the printing unit (not shown). Printing is performed on the upper surface of 42 base materials 21.

  In FIG. 2, three label portions 42 are arranged apart from each other in the width direction. However, the present invention is not limited to this configuration, and any number of label portions 42 may be arranged as long as one or more labels are arranged in the width direction. It does not need to be separated. Similarly in the longitudinal direction, the adjacent label portions 42 may not be separated from each other. Further, the feed hole 44 may be formed after the ear portion 43 is peeled off, or may be formed before being peeled off.

  The release sheet 13 is coated on the release sheet substrate 11 with an addition reaction type solventless release agent composition, and then cured by thermal curing to form a release agent layer 12 on the release sheet substrate 11. It is produced by doing.

  The release sheet substrate 11 has a function of supporting the release agent layer 12. For example, a polyester film such as a polyethylene terephthalate film or a polybutylene terephthalate film, a polyolefin film such as a polypropylene film or a polymethylpentene film, or a polycarbonate film Plastic film such as aluminum, stainless steel and other metal foils, glassine paper, high quality paper, coated paper, impregnated paper, synthetic paper, etc., and these paper base materials laminated with a thermoplastic resin such as polyethylene. ing.

The basis weight of the release sheet base material 11 is not particularly limited, but is preferably 5~300g / m ^2, and more preferably 10 to 200 g / m ^2.

  The release agent composition comprises a low-molecular-weight organopolysiloxane as a main polymer, and a polymer linear organopolysiloxane, a crosslinking agent, and a catalyst added thereto, and, if desired, a reaction inhibitor, a release adjusting agent, An adhesion improver or the like may be added. In addition, in the curing step after applying the release agent, when performing ultraviolet irradiation in addition to heating, a photoinitiator may be added.

  As the low molecular weight organopolysiloxane, an organopolysiloxane having at least two alkenyl groups in one molecule having a mass average molecular weight of 1000 to 20,000 is used. The organopolysiloxane is represented by, for example, the general formula (I). .

R ¹ R ² ₂ SiO (RRSiO) _m (RR ² SiO) _n SiR ² ₂ R ¹ (I)
Here, R is the same or different monovalent hydrocarbon having no aliphatic unsaturated bond, R ¹ is an alkenyl group, R ² is R or R ¹ , m and n represent natural numbers, and 12 ≦ (m + n ) ≦ 270.

Examples of the alkenyl group represented by R ¹ include those having 2 to 10 carbon atoms such as a vinyl group, an allyl group, a propenyl group, and a hexenyl group. R has 1 to 12 carbon atoms, preferably 1 to 10 carbon atoms, and examples thereof include alkyl groups such as a methyl group, an ethyl group and a propyl group, and aryl groups such as a phenyl group and a tolyl group. From this point, it is preferable that 80 mol% or more is a methyl group. The viscosity of the low molecular organopolysiloxane is, for example, 10 to 300 mPa · s.

  As the polymer linear organopolysiloxane, those having a mass average molecular weight of 50,000 to 500,000 are used, for example, those having 1 to 3 alkenyl groups only at the end of each molecular chain in one molecule, Or what does not have an alkenyl group is used, and what is shown by general formula (II) is used.

R ³ ₃ SiO (R ₂ SiO) _p SiR ³ ₃ (II)
Here, R is the same or different monovalent hydrocarbon having no aliphatic unsaturated bond, R ³ is an alkenyl group such as a vinyl group, or the same or different monovalent hydrocarbon group, and p represents a natural number. 700 ≦ p ≦ 7000.

  As shown by the general formula (II), the polymer linear organopolysiloxane preferably has 1 to 3 alkenyl groups only at the end of each molecular chain or has no alkenyl groups. The polymer linear organopolysiloxane has a low cross-link density by reducing the alkenyl groups in one molecule or not having alkenyl groups. Can be expressed. Moreover, when the polymer linear organopolysiloxane has no alkenyl group, the slipperiness of the release agent layer tends to be good, whereas when it has an alkenyl group, the transfer of the release agent to the adhesive sheet It tends to be prevented.

  Specific examples of the polymer linear organopolysiloxane include, for example, dimethylpolysiloxane and organopolysiloxane having one vinyl group only at each molecular chain terminal. The polymer linear organopolysiloxane is preferably added in an amount of 0.5 to 15 parts by mass, particularly preferably 0.8 to 12 parts by mass with respect to 100 parts by mass of the low molecular organopolysiloxane.

  As a crosslinking agent, for example, polyorganohydrogensiloxane having at least two silicon-bonded hydrogen atoms (SiH) in one molecule, specifically, dimethylhydrogensiloxy group end-capped dimethylsiloxane-methylhydrogensiloxane copolymer Examples thereof include a compound, a trimethylsiloxy group end-capped dimethylsiloxane-methylhydrogensiloxane copolymer, a trimethylsiloxy group end-capped poly (methylhydrogensiloxane), and poly (hydrogensilsesquioxane). In this embodiment, a cured film is formed by an addition reaction between the crosslinking agent SiH and the alkenyl group of the low-molecular-weight organopolysiloxane and the high-molecular-weight linear organopolysiloxane.

  In the release agent composition, the crosslinking agent is preferably added so that the number of silicon-bonded hydrogen atoms is 0.8 to 5.0 (molar ratio) with respect to the number of alkenyl groups. When the molar ratio is lower than 0.8, the curability of the composition is lowered. When the molar ratio is higher than 5.0, the peeling force of the release agent becomes heavy, and the peeling performance may be deteriorated.

  As the catalyst, for example, a platinum compound is used. Examples of the platinum compound include fine platinum, fine platinum adsorbed on a carbon powder carrier, chloroplatinic acid, alcohol-modified chloroplatinic acid, and chloroplatinic acid. Examples include olefin complexes, palladium and rhodium catalysts. About 1 to 1000 ppm of the catalyst is added as a platinum-based metal with respect to the total amount of the addition reaction type organopolysiloxane and the crosslinking agent.

  The viscosity of the release agent composition before curing is preferably 50 to 3000 mPa · s, more preferably 80 to 2500 mPa · s, and particularly preferably 100 to 2000 mPa · s. When the viscosity is lower than the lower limit, the release agent composition is likely to penetrate into the release sheet substrate when paper is used for the release sheet substrate, and when the viscosity is higher than the upper limit, the release agent composition of the release sheet substrate Coating becomes difficult.

The coating amount of the release agent layer 12 is not particularly limited, but is preferably 0.05-5 g / m ^2, and more preferably 0.1 to 3 g / m ^2.

  Examples of methods for applying the release agent composition onto the release sheet substrate 11 include existing methods such as gravure coating, bar coating, spray coating, spin coating, knife coating, roll coating, and die coating. Can be used.

  By using the release agent composition, the dynamic friction coefficient of the release sheet 13 is set as follows, and the slipperiness of the release sheet 13 is improved. For example, the dynamic friction coefficient between the release agent surface of the release sheet and polyethylene terephthalate is 0.1 to 0.6 in the measurement method according to JIS P8147, and the upper limit is preferably 0.55, particularly preferably 0.8. The lower limit is preferably 0.15, particularly preferably 0.2. When the dynamic friction coefficient exceeds the above upper limit value, the traveling property of the pressure-sensitive adhesive body 20 is deteriorated, and a paper jam or the like in the printer tends to occur. Moreover, when a dynamic friction coefficient becomes lower than the said lower limit, when a peeling sheet is wound up by a roll, for example in a production process, there exists a possibility that winding | disengagement may occur.

  The pressure-sensitive adhesive sheet 23 is produced by applying a pressure-sensitive adhesive on the pressure-sensitive adhesive sheet substrate 21 and forming the pressure-sensitive adhesive layer 22 on the pressure-sensitive adhesive sheet substrate 21. Thereafter, the pressure-sensitive adhesive sheet 23 is bonded to the release sheet 13 and the pressure-sensitive adhesive sheet 23 so that the pressure-sensitive adhesive layer 22 is in contact with the release agent layer 12. An adhesive is formed by applying an adhesive on the release agent layer 12 of the release sheet 13 to form an adhesive layer 22, and then attaching an adhesive sheet substrate 21 on the adhesive layer 22. 10 may be produced.

  As a method for applying the pressure-sensitive adhesive, existing methods such as a gravure coating method, a bar coating method, a spray coating method, a spin coating method, a knife coating method, a roll coating method, and a die coating method can be used.

  The pressure-sensitive adhesive sheet substrate 21 has a function of supporting the pressure-sensitive adhesive layer 22. For example, paper such as fine paper, kraft paper, glassine paper, synthetic paper, polyethylene terephthalate film, polybutylene terephthalate film, polyethylene film, polypropylene It is composed of a simple substance or a composite such as a film, a plastic film such as a polymethylpentene film or a polycarbonate film, or a metal foil such as aluminum or stainless steel. The pressure-sensitive adhesive sheet substrate 21 may be subjected to surface treatment for the purpose of improving the adhesion of the printing ink or the pressure-sensitive adhesive layer 22 on the front surface or the back surface thereof.

  An acrylic emulsion adhesive is used as the adhesive. The acrylic emulsion pressure-sensitive adhesive is composed mainly of an acrylic copolymer obtained by copolymerizing a functional group-containing monomer and another monomer such as an acrylic ester or methacrylic ester, and water as a solvent. Contains desired additives such as emulsifiers, thickeners, etc., as necessary, stabilizers, tackifiers, fillers, colorants, antioxidants, antistatic agents, ultraviolet absorbers, etc. May further be included. Examples of the functional group-containing monomer include carboxyl group-containing monomers such as acrylic acid and methacrylic acid. It is preferable that a functional group containing monomer contains 0.3-5.0 mass% on the basis (100 mass%) of the whole monomer which comprises an acrylate-type copolymer.

The coating amount of the adhesive layer 22 is not particularly limited, but is preferably 5 to 60 g / m ^2, and more preferably 10 to 40 g / m ^2.

  In this embodiment, by constituting the pressure-sensitive adhesive with an emulsion, it is not necessary to use an organic solvent for both the pressure-sensitive adhesive layer and the release agent layer, so that the environmental burden can be reduced. Further, the pressure-sensitive adhesive layer formed from the acrylic emulsion pressure-sensitive adhesive and the release agent layer formed from the release agent composition are used in combination, and the content of the functional group-containing monomer of the pressure-sensitive adhesive is the above-mentioned By making it within this range, the peeling force of the release sheet at the time of high-speed peeling and at the time of low-speed peeling can be set to a desired range.

  That is, in an environment of a temperature of 23 ° C. and a humidity of 50%, the peel force of the release sheet to the pressure-sensitive adhesive sheet (hereinafter referred to as low-speed peel force) measured under the conditions of a peel speed of 0.3 m / min and a peel direction of 180 ° is 50 to 1500 mN / 50 mm, preferably 80 to 1200 mN / 50 mm, and most preferably 100 to 1000 mN / 50 mm. When the above upper limit is exceeded, the low-speed peeling force becomes too high, and when the user peels off the label portion, an unreasonable load must be applied, and the label portion becomes difficult to peel off. On the other hand, when the value is below the lower limit value, the label portion is likely to be turned from the release sheet during printing or conveyance, and conveyance failure or the like is likely to occur.

  In addition, the peel strength of the release sheet to the pressure-sensitive adhesive sheet (hereinafter referred to as high-speed peel force) measured under the conditions of a temperature of 23 ° C. and a humidity of 50% and a peel speed of 100 m / min and a peel direction of 180 ° is 100 -3000 mN / 50 mm, preferably 150-1800 mN / 50 mm, particularly preferably 200-1600 mN / 50 mm, and the high-speed peeling force is preferably 1 to 3 times the low-speed peeling force. If the high-speed peeling force is lower than the lower limit value, the possibility that the label part will fly together with the ear part when the ear part is lifted is increased. Moreover, when exceeding the said upper limit, if an ear | edge part (adhesive sheet) is peeled at high speed at the time of scrap raising, possibility that an adhesive sheet will be cut in the middle becomes high.

  In this specification, the viscosity is measured at 25 ° C. in accordance with JIS K7117-1 4.1 (Brookfield rotary viscometer).

Moreover, a mass average molecular weight means what measured each silicone resin by gel permeation chromatography (GPC), and calculated | required it as a polystyrene conversion value. The measurement conditions are as follows.
Measuring device: Shodex GPC SYSTEM-21H (trade name, Showa Denko)
Column: Waters, two styragel (R) HR5E are used Measurement solvent: Chloroform Measurement temperature: 40 ° C
Flow rate: 1.0 ml / min Sample concentration: 1.0%

  The present embodiment will be described below using examples, but the present invention is not limited to the configurations of the following examples.

[Example 1]
A mixture of low molecular weight organopolysiloxane (containing 5 vinyl groups in one molecule, weight average molecular weight 8000) and polyorganohydrogensiloxane (molar ratio of silicon-bonded hydrogen atoms to alkenyl groups in the mixture). 8) To 100 parts by mass, 5 parts by mass of dimethylpolysiloxane having a mass average molecular weight of 4.0 × 10 ⁵ is added as a polymer linear organopolysiloxane, and further a platinum catalyst (trade name: SRX-212, Toray Dow) 1 part by mass of Corning) was added to obtain a release agent composition. The viscosity of the release agent composition was 500 mPa · s. Next, glassine paper having a basis weight of 80 g / m ² is prepared as a release sheet substrate, and a release agent composition is uniformly applied to the substrate so that the application amount is 1.0 g / m ² and heated at 140 ° C. The release sheet in which the release agent layer was formed on one surface of the substrate was obtained by treatment and curing.

An acrylic emulsion adhesive containing an acrylic ester copolymer (monomer composition: 49% by mass of 2-ethylhexyl acrylate, 50% by mass of butyl acrylate, 1% by mass of acrylic acid) on the release agent layer of the release sheet. The agent was applied using an applicator so that the coating amount after drying was 30 g / m ² . Then, after drying for 1 minute at 100 ° C., a high-quality paper having a basis weight of 64 g / m ² (trade name: NPi foam, manufactured by Nippon Paper Industries Co., Ltd.) was pasted onto the pressure-sensitive adhesive layer as a pressure-sensitive adhesive sheet base material. Got the body.

[Example 2]
As a polymer linear organopolysiloxane, instead of dimethylpolysiloxane, each molecular chain terminal has one vinyl group (that is, two vinyl groups in one molecule) and a mass average molecular weight of 4.0 × The same operation as in Example 1 was carried out except that 5 parts by mass of 10 ⁵ organopolysiloxane was added. In addition, the viscosity of the release agent composition was 500 mPa · s.

[Example 3]
The same operation as in Example 2 was carried out except that the amount of the polymer linear organopolysiloxane added was 7 parts by mass. The viscosity of the release agent composition was 1500 mPa · s.

[Example 4]
The same operation as in Example 2 was carried out except that the amount of the polymer linear organopolysiloxane added was 2 parts by mass. The viscosity of the release agent composition was 300 mPa · s.

[Example 5]
The same operation as in Example 2 was carried out except that the amount of the polymer linear organopolysiloxane added was 1 part by mass. The viscosity of the release agent composition was 250 mPa · s.

[Example 6]
The same operation as in Example 1 was performed except that dimethylpolysiloxane having a mass average molecular weight of 1.0 × 10 ⁵ was used as the polymer linear organopolysiloxane. The viscosity of the release agent composition was 250 mPa · s.

[Example 7]
The same operation as in Example 1 was carried out except that dimethylpolysiloxane having a mass average molecular weight of 6.0 × 10 ⁴ was used as the polymer linear organopolysiloxane. The viscosity of the release agent composition was 200 mPa · s.

[Example 8]
The same operation as in Example 1 was conducted except that an organopolysiloxane containing 10 vinyl groups in one molecule and having a mass average molecular weight of 8000 was used as the low molecular weight organopolysiloxane. The viscosity of the release agent composition was 500 mPa · s.

[Example 9]
The same procedure as in Example 1 was performed except that the monomer composition of the acrylic emulsion adhesive was changed to 47% by mass of acrylic acid-2-ethylhexyl, 50% by mass of butyl acrylate, and 3% by mass of acrylic acid.

[Example 10]
The same procedure as in Example 1 was carried out except that the monomer composition of the acrylic emulsion adhesive was changed to 40% by mass of acrylic acid-2-ethylhexyl, 50% by mass of butyl acrylate, and 10% by mass of acrylic acid.

[Comparative Example 1]
The same procedure as in Example 1 was performed except that the high-molecular linear organopolysiloxane was not added. The viscosity of the release agent composition was 150 mPa · s.

[Comparative Example 2]
The same procedure as in Example 1 was performed except that 5 parts by mass of dimethylpolysiloxane having a mass average molecular weight of 3.0 × 10 ³ was added instead of the polymer linear organopolysiloxane. The viscosity of the release agent composition was 170 mPa · s.

[Comparative Example 3]
The same procedure as in Example 1 was performed except that 30 parts by mass of dimethylpolysiloxane having a weight average molecular weight of 3.0 × 10 ³ was added instead of the polymer linear organopolysiloxane. The viscosity of the release agent composition was 200 mPa · s.

(1) Residual adhesion rate measurement A polyester tape (product name: NO.31B, manufactured by Nitto Denko Corporation) is bonded to the surface of the release agent layer side of a release sheet having a width of 25 mm and a length of 20 cm, and 20 g / cm is formed thereon. ^After applying a load of ² and aging at 70 ° C. for 24 hours, the polyester tape was peeled off from the release sheet and attached to a stainless steel plate. The resistance (A) when the polyester tape was peeled off from the stainless steel plate at an angle of 180 ° at a speed of 0.3 m / min was measured. A polyester tape not bonded to a release sheet as a blank was bonded to a stainless steel plate, and the resistance (B) was measured in the same manner. The residual adhesion rate was expressed as 100 × (A / B). If the residual adhesion rate is 90% or more, it is judged as good in Table 1 as being good. If it was 80% or more and less than 90%, it was marked as Δ because it was usable. If it was less than 80%, it was marked as x because it could not be used.

(2) Slip property test About each peeling sheet, the dynamic friction coefficient was measured according to JISP8147. First, a polyethylene terephthalate film was bonded to the bottom surface of a metal piece (1000 g) having a bottom surface of 6 cm × 10 cm and a height of 2 cm. This metal piece was placed on the surface of the release sheet on the release agent layer side so that the attached film was in contact with the release agent layer. Using a tensile tester, the metal piece was pulled in the horizontal direction at a speed of 1.0 m / min, and the force F (N) when the metal piece was in a stable state was measured, and F / (1000 × 9.8 × 10 ^{− 3} ) was defined as the dynamic friction coefficient. In Table 1, it was marked as “good” if the dynamic friction coefficient was 0.1 or more and 0.6 or less. If it was less than 0.1 or more than 0.6, it was marked as unusable.

(3) Paper jam test For each pressure-sensitive adhesive body, feed holes were formed at both ends in the width direction, and punching and scrap removal were performed to produce a printer label as shown in FIG. Using a printing machine (trade name: VSP-4971, manufactured by Fujitsu Limited), a test was performed to determine whether a paper jam occurred when printing was performed on the printer label. The test was performed at a speed of 8200 lines / minute and a test time of 10 minutes.

(4) Measurement of peeling force The peeling force was measured for each pressure-sensitive adhesive body. The peel force was measured for each pressure-sensitive adhesive after being left for 1 day in an environment of a temperature of 23 ° C. and a humidity of 50%, and then left for 30 days. The adhesive body is cut into a width of 20 mm and a length of 200 mm, the release sheet is fixed by a tensile tester, and the adhesive sheet is pulled in a 180 ° direction at a predetermined release speed, thereby measuring the peeling force of the release sheet to the adhesive sheet. did. At this time, the peeling speed was set to 0.3 m / min and 100 m / min, respectively, and the low speed peeling force and the high speed peeling force were measured in an environment of a temperature of 23 ° C. and a humidity of 50%.

  As apparent from Table 1, Examples 1 to 10 to which a high molecular weight linear organopolysiloxane having a molecular weight of 50,000 to 500,000 was added had good results in both the residual adhesion rate and the slipperiness. It was. Moreover, when the addition amount of the polymer linear organopolysiloxane was the same, the higher the molecular weight, the better the slipping property. Also, when the molecular weight is the same, when the polymer linear organopolysiloxane contains an alkenyl group, the residual adhesion rate is higher and the slipperiness is lower than when the alkenyl group is not contained. It became a tendency to become.

  On the other hand, in Comparative Examples 1 and 2 in which the release agent did not contain a high molecular weight linear organopolysiloxane having a molecular weight of 50,000 to 500,000, the slipperiness was poor and paper jam occurred in the paper jam test. Further, as in Comparative Example 3, when a large amount of a linear organopolysiloxane having a low molecular weight was added, the slipping property was improved, but the residual adhesion rate was low and the level was not reached.

  Moreover, in Examples 1-9, both the high-speed and low-speed peeling force became an appropriate value by using the adhesive containing 1-3 mass% of functional group containing monomers. On the other hand, when the content of the functional group-containing monomer is 10% by mass as in Example 10, regardless of whether the same release sheet as in Example 1 was used, either high speed or low speed release force after 30 days was used. The result was too heavy. From this result, for the release agent composition of the present invention, if an acrylic emulsion pressure-sensitive adhesive having a functional group-containing monomer content of about 1 to 5% by mass is used, both high-speed and low-speed release forces are obtained. Understand that it will be appropriate.

It is typical sectional drawing which shows the adhesive sheet which concerns on this embodiment. It is a typical top view when an adhesive sheet is applied to a printer label.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Adhesive body 11 Release sheet base material 12 Release agent layer 13 Release sheet 21 Adhesive sheet base material 22 Adhesive layer 23 Adhesive sheet 42 Label part 43 Ear part 44 Feed hole

Claims (10)

A pressure-sensitive adhesive sheet provided with a pressure-sensitive adhesive layer on one surface of a pressure-sensitive adhesive sheet base material is brought into contact with a pressure-sensitive adhesive sheet on one surface of the pressure-sensitive adhesive sheet base material, and the pressure-sensitive adhesive layer is in contact with the pressure-sensitive adhesive layer. In the pressure-sensitive adhesive body that is adhered and configured,
The release agent layer comprises a low molecular weight organopolysiloxane having at least two alkenyl groups in one molecule having a mass average molecular weight of 1000 to 20,000, and a polymer linear chain having a mass average molecular weight of 50,000 to 500,000. A pressure-sensitive adhesive comprising an addition reaction type solventless release agent composition containing an organopolysiloxane formed by curing.   The pressure-sensitive adhesive body according to claim 1, wherein the release agent composition has a viscosity before curing of 50 to 3000 mPa · s.   The pressure-sensitive adhesive according to claim 1, wherein the polymer linear organopolysiloxane has 1 to 3 alkenyl groups only at each molecular end in one molecule, or has no alkenyl groups. body.   2. The pressure-sensitive adhesive according to claim 1, wherein a coefficient of dynamic friction between the surface of the release agent layer of the release sheet and polyethylene terephthalate is 0.1 to 0.6 in a measurement method according to JIS P8147.   The pressure-sensitive adhesive body according to claim 1, wherein the pressure-sensitive adhesive layer is composed of an acrylic emulsion pressure-sensitive adhesive.   The pressure-sensitive adhesive body according to claim 5, wherein the acrylic emulsion pressure-sensitive adhesive contains an acrylate-based copolymer containing 0.3 to 5.0 mass% of a functional group-containing monomer.   The peeling force of the release sheet to the pressure-sensitive adhesive sheet, measured under conditions of a peeling speed of 0.3 m / min and a peeling direction of 180 ° in an environment of a temperature of 23 ° C. and a humidity of 50%, is 50 to 1500 mN / 50 mm. The pressure-sensitive adhesive body according to claim 1.   In an environment of a temperature of 23 ° C. and a humidity of 50%, the peeling force of the release sheet with respect to the pressure-sensitive adhesive sheet measured under the conditions of a peel rate of 100 m / min and a peel direction of 180 ° is 100 to 3000 mN / 50 mm. The pressure-sensitive adhesive body according to claim 1. At both ends in the width direction of the release sheet, feed holes for sending the adhesive body in the longitudinal direction are formed,
2. The adhesive sheet according to claim 1, wherein a part of the pressure-sensitive adhesive sheet is removed from the release sheet as an ear part, and a part left on the release sheet is used as a label part for printing. The adhesive body as described in. In the release sheet provided with a release agent layer on one side of the release sheet substrate,
The release agent layer comprises a low molecular weight organopolysiloxane having at least two alkenyl groups in one molecule having a mass average molecular weight of 1000 to 20,000, and a polymer linear chain having a mass average molecular weight of 50,000 to 500,000. A release sheet, which is formed by curing an addition reaction type solventless release agent composition containing organopolysiloxane.