JP2004346213A - Mold-releasing agent and adhesive laminated tape - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mold-releasing agent not containing a silicone-based gas-generating component, having good mold release property to various adhesives, having little variation of peel force and capable of retaining low peel force also after placing it under heating in a state laminated to the adhesive. <P>SOLUTION: The mold-releasing agent comprises (A) an ethylene-based copolymer composed of only ethylene and one or more kinds of α-olefins (excluding ethylene) and (B) a propylene-based polymer having ≥80 wt.% polypropylene content in a weight ratio of (40:60) to (90:10). <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【００６９】
【発明の効果】
以上説明した本発明によれば、シリコーン系発ガス成分を含まず、種々の粘着剤に対して良好な離型性を有すると共に、剥離力の変動が小さく、且つ粘着剤と貼り合わせて加熱下に置いた後も低い剥離力を保持できる離型剤が提供され、本発明の工業的価値は顕著である。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a release agent and an adhesive laminated tape. In this specification, the term “adhesion” has a broad meaning including adhesion and the like.
[0002]
[Prior art]
Release agents are widely used to protect the adhesive surface of adhesive tapes. One of the most excellent release agents in terms of release performance is a silicone release agent. By the way, a small amount of a siloxane-based gas is contained in a silicone-based release agent, and this siloxane-based gas may cause corrosion and other serious obstacles depending on applications. Fluororesin-based release agents have been proposed in place of silicone-based release agents, but their release performance is not always satisfactory.
[0003]
The release agent composed of the polyethylene resin composition includes a release agent mainly composed of a low-density polyethylene resin (for example, see Patent Literatures 1 and 2) and a release agent mainly composed of a high-density polyethylene resin. Agents (see, for example, Patent Documents 3 and 4). A release agent containing a low-density polyethylene resin as a main component requires a large peeling force, and when used as a pressure-sensitive adhesive layer protective film, a part of the adhesive layer migrates to the surface of the release layer during peeling or peels off. The shape of the surface of the adhesive layer afterwards causes peeling called stick-slip that becomes pulse-like, or when heated in a state of being bonded to an adhesive, the peeling force increases or the adhesive force of the adhesive after peeling There is a problem such as lowering.
[0004]
Further, a release material using a thermoplastic elastomer-olefin elastomer containing polypropylene as a main component has been proposed (for example, see Patent Document 5), and a release material comprising a propylene ethylene copolymer and a polypropylene composition has been proposed (for example, Patent Document 6). However, these have high peeling strength and are not practically sufficient.
[0005]
[Patent Document 1]
JP-B-51-20205
[Patent Document 2]
Japanese Patent Publication No. Hei 11-508958
[Patent Document 3]
JP 2000-239624 A
[Patent Document 4]
JP-A-2000-119411
[Patent Document 5]
JP 2001-516790 A
[Patent Document 6]
JP 2000-218745 A
[0006]
[Problems to be solved by the invention]
The present invention has been made in view of the above circumstances, and its object is to include a silicone-based generated gas component, to have good releasability for various pressure-sensitive adhesives, and to have a small variation in peeling force. Another object of the present invention is to provide a release agent capable of maintaining a low peeling force even after being bonded to an adhesive and placed under heating.
[0007]
[Means for Solving the Problems]
That is, a first gist of the present invention is to provide an ethylene copolymer (A) comprising only ethylene and one or more α-olefins (excluding ethylene) and a propylene copolymer having a polypropylene content of 80% by weight or more. A mold release agent comprising a polymer (B), wherein the weight ratio of the ethylene copolymer (A) to the propylene polymer (B) is from 40:60 to 90:10.
[0008]
A second gist of the present invention resides in an adhesive laminate comprising an adhesive layer and a release layer, wherein the release layer comprises the above-mentioned release agent.
[0009]
A third aspect of the present invention is an adhesive laminated tape in which an adhesive layer of an adhesive laminate comprising an adhesive layer and a release layer is provided on at least one surface of a substrate so as to be in contact with the substrate, The adhesive layered tape is characterized in that the release layer comprises the release agent described above.
[0010]
A fourth gist of the present invention is an adhesive laminated tape in which a base material, a release layer, an adhesive layer, and a base material for an adhesive layer are laminated in this order, wherein the release layer comprises the above release agent. The present invention resides in an adhesive laminated tape characterized in that:
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in detail. First, the release agent of the present invention will be described. The release agent of the present invention contains, as essential components, an ethylene copolymer (A) and a propylene polymer (B) described below.
[0012]
The ethylene-based copolymer (A) comprises only ethylene and one or more α-olefins (excluding ethylene). Examples of the α-olefin include propylene, 1-butene, 1-pentene, 3-methyl-1-butene, 1-hexene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-heptene, Α-olefins having about 3 to 20 carbon atoms, such as 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, and 1-eicosene. Among these, any one or more of propylene, butene, hexene, and octene are preferred. The copolymerization ratio of the α-olefin in the ethylene copolymer (A) is usually 1 to 25 mol%, preferably 3 to 15 mol%. If the copolymerization ratio of the α-olefin is too high and the ethylene content is too low, the heat resistance of the release agent tends to decrease.
[0013]
In the present invention, an ethylene copolymer (A) produced using a metallocene catalyst is particularly preferred. The metallocene-based catalyst provides a polyolefin having a narrow molecular weight distribution and a low molecular weight component, and can perform the copolymerization uniformly, so that the generation of components whose comonomer content is significantly different from the average composition is also suppressed. . Therefore, the release agent using the ethylene-based copolymer (A) produced using the metallocene-based catalyst has a low stickiness and can effectively gel at the time of cross-linking. Chemical resistance can be increased. The production of the ethylene copolymer (A) can be performed by any known polymerization method such as solution polymerization, gas phase polymerization, and slurry polymerization.
[0014]
Examples of the propylene-based polymer (B) used in the present invention include a propylene homopolymer, a propylene-α-olefin random copolymer, and a propylene-α-olefin block copolymer. Examples of the α-olefin include propylene, 1-butene, 1-pentene, 3-methyl-1-butene, 1-hexene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-heptene, Α-olefins having about 3 to 20 carbon atoms, such as 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, and 1-eicosene. The α-olefin used as a comonomer may be one type, or two or more types may be used in combination. The polypropylene content in the propylene-based polymer (B) is at least 80% by weight, preferably at least 85% by weight. When the polypropylene content is less than 80% by weight, the heat resistance decreases.
[0015]
The propylene-based polymer (B) is produced by a known method. For example, a Ziegler-Natta catalyst, a metallocene catalyst, or the like is used as a catalyst, and is manufactured by a known process such as a batch method, a gas phase method, or a slurry method.
[0016]
The melting point of the propylene-based polymer (B) is usually 80 ° C. or higher, preferably 120 ° C. or higher, from the viewpoint of the release agent and heat resistance, and the upper limit is usually 165 ° C. When the melting point is lower than 80 ° C., the heat resistance of the propylene-based polymer (B) is reduced because it is close to the melting point of the ethylene-based copolymer (A).
[0017]
In order to control the melting point of the propylene-based polymer (B), a method of changing the amount and type of the α-olefin copolymerized with propylene, and controlling the stereoregular distribution and positional isomerism of propylene in the propylene homopolymer A method of controlling the crystallization rate by adding a component compatible with the propylene-based polymer (B) such as a norbornene polymer, a method of using a crystallization nucleating agent to change the crystal system and the crystallization start temperature, and the like. , Various methods can be used.
[0018]
The weight average molecular weight of the propylene polymer (B) is usually 1 × 10⁴Above, preferably 3 × 10⁴That is all. Weight average molecular weight is 1 × 10⁴If the value is less than the above, the mechanical strength of the release agent becomes small, and when the release layer composed of the release agent is peeled off from the adhesive layer, the release becomes poor, or the release layer is partially formed on the adhesive layer. May remain.
[0019]
In the present invention, a functional group can be added to the ethylene-based copolymer (A) and / or the propylene-based polymer (B) in order to obtain a release agent having excellent substrate adhesion. Functional groups include epoxy, acid anhydride, carboxyl, hydroxyl, amino, isocyanate, trimethoxysilyl, and other reactive functional groups, vinyl, isopropenyl, and (meth) acrylate groups. And a group having an unsaturated bond such as an allyl group.
[0020]
The functional group may be imparted by a conventional method, for example, by subjecting an ethylene copolymer (A) and / or a propylene polymer (B) to an addition reaction of a monomer having a functional group in the presence of a peroxide. Known peroxides such as ketone peroxide, hydroperoxide and diacyl peroxide are used as the peroxide. The amount of the functional group is usually at most 10 mol%, preferably at most 5 mol%. If the number of functional groups is too large, the release property of the release agent may be impaired.
[0021]
The release agent of the present invention contains an ethylene-based copolymer (A) and a propylene-based polymer (B) as essential components, but may further contain other additional components. When a functional group is provided to the ethylene-based copolymer (A) and / or the propylene-based polymer (B), examples of the additional component include a crosslinking agent, that is, a functional group that reacts with the functional group of the polyolefin. Compounds having a plurality of compounds are exemplified. The usage ratio of such a crosslinking agent is usually 0.1 to 10, preferably 0.5 to 2, as a molar ratio of the functional group of the polyolefin / the functional group of the crosslinking agent. When the molar ratio of the functional groups is out of this range, the number of remaining unreacted functional groups increases, and the releasability generally decreases. Other additional components include antiblocking agents, antioxidants, pigments, UV absorbers, fillers, antioxidants, and the like.
[0022]
The release agent of the present invention can be produced by blending various additional components with the ethylene-based copolymer (A) and the propylene-based polymer (B), if desired, and dissolving in a solvent or melt-kneading. . The weight ratio of the ethylene-based copolymer (A) to the propylene-based polymer (B) is from 40:60 to 90:10, preferably from 40:60 to 80:20. When the proportion of the propylene-based polymer (B) is less than the above range, the peeling force with the pressure-sensitive adhesive and the heat resistance of the release agent decrease, and when it exceeds the above range, the heat resistance of the release agent is excellent. The peel force increases.
[0023]
Next, the adhesive laminate and the adhesive laminated tape of the present invention will be described. The adhesive laminate of the present invention is an adhesive laminate comprising an adhesive layer and a release layer, wherein the release layer comprises the above-mentioned release agent. Then, it is used for various types of adhesive laminated tapes by appropriately using a base material.
[0024]
<Adhesive laminated tape-1>
In this embodiment, an adhesive laminate is provided on a substrate such that the adhesive layer and the substrate are adjacent to each other. That is, the layer configuration is base material / adhesive layer / release layer. In use, the release layer may be peeled off to expose the adhesive layer surface and adhere to the object.
[0025]
<Adhesive laminated tape-2>
In this embodiment, an adhesive laminate is provided on a substrate such that the release layer and the substrate are adjacent to each other, and a substrate for an adhesive layer is further provided on the adhesive layer side of the adhesive laminate. That is, the layer configuration is: base material / release layer / adhesive layer / base material. At the time of use, the substrate and the release layer may be peeled off, and the adhesive layer surface may be exposed to adhere to the target.
[0026]
<Adhesive laminated tape-3>
In this embodiment, the adhesive laminate is provided on both surfaces of the adhesive layer base material such that the base material and the adhesive layer are adjacent to each other. That is, the layer configuration is: release layer / adhesive layer / substrate / adhesive layer / release layer. In use, the release layer covering one adhesive layer is peeled off, the outer surface of the adhesive layer is exposed and adhered to one object, and then the release layer covering the other adhesive layer is applied. By peeling the mold layer and exposing the outer surface of the adhesive layer to adhere to the other object, it can be used as a double-sided adhesive tape for adhering two objects.
[0027]
<Adhesive laminated tape-4>
In this embodiment, a release layer is provided on the surface of the adhesive layer of the adhesive laminate. That is, the layer configuration is: release layer / adhesive layer / release layer. In use, one release layer is peeled off, one surface of the adhesive layer is exposed and adhered to one object, and then the other release layer is peeled and the other surface of the adhesive layer is exposed and the other Can be used as a double-sided adhesive tape for adhering two objects to each other.
[0028]
<Adhesive laminated tape-5>
In this embodiment, an adhesive layer is provided on one surface of the base material, a release layer is provided on the other surface, and the adhesive laminate is wound into a roll without using the above-mentioned adhesive laminate. . That is, the layer configuration is: adhesive layer / substrate / release layer. Since the release layer has adhesiveness to the base material, when used, it may be unwound and peeled off at the interface between the adhesive layer and the release layer to expose the adhesive layer surface and adhere to the object.
[0029]
In any of the above-described adhesive laminated tapes, the thickness of the release layer is increased, or the release layer is integrated with the release layer base material having adhesion to the release layer, and the release is performed. Mechanical strength at the time of peeling the layer can be ensured.
[0030]
In addition, in the case of the adhesive laminated tape of any configuration, the release layer substrate is used as a release layer, and the adhesive layer substrate is used as an integral part of the adhesive layer, if necessary. The base material for adhesion is required to have adhesion and mechanical strength with a release agent, and the adhesion layer base material is required to have adhesion and mechanical strength with an adhesive. The base material used for the above-mentioned wound adhesive laminated tape serves both as a base material for the release layer and a base material for the adhesive layer.
[0031]
As the base material used for the adhesive laminated tape including the wound adhesive laminated tape, a common substrate, for example, polyethylene terephthalate, polyester such as polybutylene terephthalate, polypropylene, polyethylene, polyolefin such as polymethylpentene, polycarbonate, etc. Paper, such as a film made of the above resin, glassine paper, high-quality paper, coated paper, impregnated paper, and synthetic paper; and metal foil such as aluminum and stainless steel. The thickness of the substrate is usually 10 to 100 μm, preferably 25 to 50 μm.
[0032]
The base material may be subjected to a corona treatment, a plasma treatment, a flame plasma treatment, or the like, or a primer layer or the like, in order to improve the adhesiveness with the adhesive layer or the release layer. As the primer layer, use of a polymer material (a so-called anchor coating agent) such as polyethylene, polypropylene, styrene-based copolymer, polyester, polyurethane, polyvinyl alcohol, polyethyleneimine, polyacrylate, polymethacrylate, or a modified product thereof. Can be done.
[0033]
In the production of the above tape, the formation of the adhesive layer and the release layer may be performed by a conventional method. Usually, the release layer is formed by applying a release agent onto a base material, melt-extruding the release agent into a sheet from an extruder and laminating it on the base material, or extruding a base material and a release agent. It is formed by coextrusion from a machine.
[0034]
As the pressure-sensitive adhesive, those usually referred to as pressure-sensitive adhesives such as acrylic, rubber, polyurethane, and silicone are mainly used, but other pressure-sensitive adhesives can also be used. The adhesive layer is formed by applying the adhesive as it is or as a solution on the base material or the release layer provided on the base material, transferring the adhesive layer applied to another base material by transfer coating, It can be formed by co-extruding a material, a release agent and an adhesive with an extruder.
[0035]
In the production of the laminate, it is excellent in terms of productivity to melt-extrude a plurality of layers at the same time, such as by co-extrusion of the base material layer and the release layer.
[0036]
When the release layer is formed by a melt extrusion method, the melt index of the release agent at 230 ° C. and 2.16 kgf is usually 0.5 to 40 g / 10 minutes, preferably 1 to 20 g / 10 minutes. . Extrusion moldability is reduced if the melt index is larger or smaller.
[0037]
In the case where the base material and the release layer, and further, the base material, the release layer and the adhesive layer are co-extruded, they are continuously stretched uniaxially or biaxially to reduce the thickness and improve the strength. It can also be done. The stretching ratio is usually 2 to 10 times. The thickness of the release layer is usually 0.5 to 150 μm, preferably 0.5 to 10 μm, and more preferably 0.5 to 5 μm. If the thickness of the release layer is too small, it is difficult to ensure uniformity of the thickness, and if it is too large, the elastic modulus of the laminate decreases.
[0038]
【Example】
Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the following examples unless it exceeds the gist of the present invention. In addition, the measuring method of the physical property in an Example was performed by the following methods.
[0039]
(1) Evaluation of releasability at normal temperature:
After preparing the adhesive laminated tape, it is cured at 25 ° C. and 50 RH for 72 hours to be stabilized. Next, the adhesive laminated tape is cut into a width of 25 mm and a length of 150 mm, the back surface of the base material adjacent to the adhesive layer is fixed to a stainless steel plate, and a peeling tester is used at 300C / 50 RH in an atmosphere of 25 ° C and 50 RH. The interface between the release layer and the pressure-sensitive adhesive layer is peeled 180 degrees at a pulling speed of min, and the force (normal peel force) at that time is measured. The results were expressed as the average of five measurements. The smaller the normal release force, the easier the release from the adhesive layer and the better the releasability at normal temperature.
[0040]
(2) Evaluation of releasability under heating:
After preparing the adhesive laminated tape, it is cured at 25 ° C. and 50 RH for 72 hours to be stabilized. Next, the adhesive laminated tape was weighed at 20 g / cm.²Hold at 100 ° C. for 1 hour under load. Next, after cooling at room temperature, the adhesive laminated tape was cut into a width of 25 mm and a length of 150 mm, the back surface of the base material adjacent to the adhesive layer was fixed to a stainless steel plate, and a peel tester was used at 25 ° C. The interface between the release layer and the adhesive layer is peeled off by 180 degrees at a pulling speed of 300 mm / min under an atmosphere of 50 RH. The force at that time (heat peeling force) is measured. The results were expressed as the average of five measurements. The smaller the heat peeling force, the easier the peeling from the adhesive layer, and the better the releasability under heating.
[0041]
Further, as the ethylene copolymer (A), the propylene polymer (B) and the pressure-sensitive adhesive, those described below were used. The molecular weight and the melting point were measured by the following method.
[0042]
(3) Molecular weight:
Calculated by gel permeation chromatography using a calibration curve made with standard polystyrene. The measurement conditions are as shown in Table 1 below.
[0043]
[Table 1]
Model: Waters, GPC150C
Solvent: orthodichlorobenzene
Temperature: 140 ° C
Injection concentration: 0.1% by weight
Injection volume: 200 μl
Flow rate: 1.0 ml / min
Detector: IR. 3.42 μm wavelength
Column: AD806MS, manufactured by Showa Denko KK
Column size: 30cm x 3
Calculation method of molecular weight: Calculated as molecular weight of linear polyethylene by universal calibration method
[0044]
(4) Measurement of melting point:
The measurement was performed as follows using a DSC “DSC-7” manufactured by PerkinElmer. That is, first, after preliminarily constant temperature at 200 ° C. for 10 minutes, the temperature is cooled to −20 ° C./min to 20 ° C. and constant temperature for 5 minutes. Next, the temperature is raised at 20 ° C./min. The endothermic peak position of the DSC peak accompanying the melting in this temperature raising process is defined as the melting point. The measurement was performed in a nitrogen atmosphere, and the sample weight was 7 mg.
[0045]
(EP1)
It is an ethylene-propylene copolymer produced using a metallocene catalyst. The composition determined by H-NMR was ethylene / propylene = 74/26 (weight ratio), the weight average molecular weight determined by GPC was 97000, the ratio of the weight average molecular weight to the number average molecular weight was 2.3, and the density was 0.3. 863 g / cc and MFR was 3.2 g / 10 min.
[0046]
(EP2)
It is an ethylene-propylene copolymer produced using a metallocene catalyst. The composition determined by H-NMR was ethylene / propylene = 73/27 (weight), the weight average molecular weight determined by GPC was 71,000, the ratio of the weight average molecular weight to the number average molecular weight was 2.1, and the density was 0.865 g. / Cc, MFR was 6 g / 10 min.
[0047]
(EP3)
It is an ethylene-hexene random copolymer produced using a metallocene catalyst. The composition determined by H-NMR was ethylene / hexene = 90/10 (molar ratio), the weight average molecular weight determined by GPC was 70100, the ratio of the weight average molecular weight to the number average molecular weight was 2.3, and the density was 0.3. 880 g / cc and MPR were 3.5 g / 10 min.
[0048]
(EP4)
After mixing 100 parts by weight of the above-mentioned EP, 3 parts by weight of 2-hydroxyethyl methacrylate, and 0.15 parts by weight of 2,5-dimethyl-2,5-di-tert-butyl peroxide: kneading with Labo Plastomill. A modified ethylene-hexene random copolymer having a hydroxyl group, obtained by kneading at 180 ° C. for 3 minutes at a rotation speed of 60 rpm in a nitrogen atmosphere using a machine (manufactured by Toyo Seiki Co., Ltd.). 1724 cm by FT-IR spectrum^{− 1}The content of 2-hydroxyethyl methacrylate estimated from the measured value of the characteristic absorption intensity of the carbonyl group was 0.9% by weight. The density was 0.881 g / cc and the MFR was 4.2 g / 10 minutes.
[0049]
(PP1)
Propylene was polymerized using a metallocene catalyst. The weight average molecular weight determined by GPC was 394400, and the ratio of the weight average molecular weight to the number average molecular weight was 2.4. Melting point was 155 ° C.
[0050]
(PP2)
Propylene and ethylene (weight ratio 97.4: 2.6) were polymerized using a Ziegler-Natta catalyst. The weight average molecular weight determined by GPC was 397000, and the ratio of the weight average molecular weight to the number average molecular weight was 4.2. Melting point was 123 ° C.
[0051]
(PP3)
Propylene and ethylene (weight ratio 94.0: 6.0) were polymerized using a Ziegler-Natta catalyst. The weight average molecular weight determined by GPC was 210,000, and the ratio of the weight average molecular weight to the number average molecular weight was 5.3. Melting point was 109 ° C.
[0052]
(Polyacrylate ester-based adhesive A)
100 parts by weight of n-butyl acrylate and 5 parts by weight of acrylic acid are dissolved in toluene and polymerized by a conventional method using benzoyl peroxide to obtain a solution of an acrylic polymer having a weight average molecular weight of about 500,000 (solid content: 50 % By weight). Ethyl acetate was added thereto so that the solid content became 30%, and then 3 parts by weight of an isocyanate-based cross-linking agent was added per 100 parts by weight of the acrylic polymer to obtain a polyacrylate-based pressure-sensitive adhesive A.
[0053]
Example 1
Propylene polymer 1 (PP1) and ethylene propylene copolymer 1 (EP1) were blended at the weight ratio shown in Table 1, and kneaded using a twin screw extruder at 210 ° C. for an average residence time of 3 minutes. A mold was produced. This release agent was extruded from a T-die molding machine at 220 ° C. to obtain a release sheet composed of only a release layer. The thickness of the release sheet was 50 μm.
[0054]
Using an applicator (manufactured by Taiyo Kiki Co., Ltd .: for 100 μm), a polyacrylic ester-based adhesive solution at 23 ° C. on a 25 μm thick polyester film so that the coating liquid has a thickness of 100 μm and a width of 8 cm. A was applied. Two seconds after the application, drying was performed for 2 minutes in a dryer (Safeben Dryer N50S5, manufactured by Satake Chemical Instruments Co., Ltd.) heated to 80 ° C. Then, it was taken out and cooled to room temperature to obtain an adhesive sheet comprising an adhesive layer and a substrate.
[0055]
Next, two minutes after cooling to room temperature, the pressure-sensitive adhesive sheet was placed on the release sheet, and a 2 kg roller was reciprocated once at a speed of 30 cm / min. Was crimped. Thus, the adhesive laminated tape 1 in which the release layer, the adhesive layer, and the substrate were laminated in this order was produced.
[0056]
Nitto Denko Corporation: N502 tape was used as an adhesive sheet, placed on the release sheet, and a 2 kg roller was reciprocated from above at a speed of 30 cm / min to press the adhesive layer and the release layer. Thereby, the adhesive laminated tape 2 in which the release layer, the adhesive layer, and the base material were laminated in this order was produced.
[0057]
Examples 2 to 6
A propylene polymer and an ethylene α-olefin polymer were blended at a weight ratio shown in Table 1, and kneaded using a twin-screw extruder at 230 ° C. for an average residence time of 3 minutes to produce a release agent.
[0058]
From a T-die molding machine, an equal weight blend of LLDPE (density 0.93 g / cc, melt index 2.0 g / 10 min) and release agent-containing propylene polymer and the above release agent are coextruded at 240 ° C. A release sheet comprising a substrate and a release layer was obtained. The thickness of the substrate was 25 μm, and the thickness of the release layer was 4 μm.
[0059]
In Example 6, a zeolite-based anti-blocking agent (average particle size: 2 μm) was mixed with 100 parts by weight of the release agent in the production of the release agent so as to be 2 parts by weight.
[0060]
Using an applicator (manufactured by Taiyo Kiki Co., Ltd .: for 100 μm), apply a polyacrylate pressure-sensitive adhesive solution A on a 25 μm-thick polyester film so that the coating liquid has a thickness of 100 μm and a width of 8 cm. It was applied at 23 ° C. Two seconds after the application, drying was performed for 2 minutes in a dryer (Safetaken Dryer N50 S5, manufactured by Satake Chemical Instruments Co., Ltd.) heated to 80 ° C. Then, it was taken out and cooled to room temperature to obtain an adhesive sheet comprising an adhesive layer and a substrate.
[0061]
Next, two minutes after cooling to room temperature, the above-mentioned pressure-sensitive adhesive sheet was placed on the release sheet, and a 2-kg roller was reciprocated from the top at a speed of 30 cm / min. Was crimped. As a result, an adhesive laminated tape in which the substrate, the release layer, the adhesive layer, and the substrate were laminated in this order was prepared.
[0062]
Nitto Denko Corporation: N502 tape was used as an adhesive sheet, placed on the release sheet, and a 2 kg roller was reciprocated from above at a speed of 30 cm / min to press the adhesive layer and the release layer. Thereby, the adhesive laminated tape 2 in which the release layer, the adhesive layer, and the base material were laminated in this order was produced.
[0063]
Example 7
A propylene polymer and a functional group-modified ethylene 1-hexene copolymer (EP-4) shown in Table 1 were dissolved in toluene heated to 60 ° C, and then cooled to give a 2% by weight toluene solution of a release agent. Was prepared. To this release agent solution, "NY718A" (a 76% by weight butyl acetate solution of trifunctional isocyanate obtained by adding 3 mol of aliphatic diisocyanate to 1 mol of triol) manufactured by Mitsubishi Chemical Corporation was added, and a release agent containing a crosslinking agent was added. An agent solution was prepared. This solution contains a crosslinking agent in an amount such that the isocyanate group becomes 1.1 equivalents to 2-hydroxyethyl methacrylate contained in the polyolefin (PE-3).
[0064]
The above toluene solution was applied on a 25 μm-thick polyester film so that the thickness after drying became 0.1 μm, and dried in an atmosphere at 150 ° C. for 1 minute to obtain a release sheet.
[0065]
Then, a polyacrylate pressure-sensitive adhesive solution A is applied on the release layer of the release sheet so that the thickness after drying becomes 40 μm, and dried at 80 ° C. for 5 minutes. Was formed. A polyester film having a thickness of 25 μm was adhered to the adhesive layer as a substrate to prepare an adhesive laminated tape 1 in which a substrate, a release layer, an adhesive layer, and a substrate were laminated in this order. Further, an adhesive laminated tape 2 was produced in the same manner as in Example 2.
[0066]
Comparative Examples 1-3
Adhesive laminated tapes 1 and 2 were obtained in exactly the same manner as in Example 1 except that the compositions shown in Table 1 were used as release agents.
[0067]
Comparative Example 4
In the same manner as in Example 2 except that ethylene α-olefin copolymer (EP1) was used as a release agent, and only the substrate was LLDPE (density 0.93 g / cc, melt index 2.0 g / 10 min). Thus, adhesive laminated tapes 1 and 2 in which a substrate, a release layer, an adhesive layer, and a substrate were laminated in this order were produced.
[0068]
[Table 2]

[0069]
【The invention's effect】
According to the present invention described above, it does not contain a silicone-based gas generating component, has good releasability for various pressure-sensitive adhesives, has a small variation in peeling force, and is bonded to a pressure-sensitive adhesive under heating. The present invention provides a release agent capable of maintaining a low peel force even after being placed in the mold, and the industrial value of the present invention is remarkable.

Claims (7)

An ethylene-based copolymer (A) consisting solely of ethylene and one or more α-olefins (excluding ethylene) and a propylene-based polymer (B) having a polypropylene content of 80% by weight or more; A release agent, wherein the weight ratio of the copolymer (A) to the propylene-based polymer (B) is from 40:60 to 90:10. The release agent according to claim 1, wherein the α-olefin other than ethylene constituting the ethylene copolymer (A) is any one or more of propylene, butene, hexene, and octene. The release agent according to claim 1, wherein the propylene polymer (B) has a melting point of 80 ° C. or higher. The ethylene-based copolymer (A) and / or the propylene-based polymer (B) have a functional group and further contain a reactive compound (C) capable of reacting with the functional group. 3. The release agent according to any one of 3. An adhesive laminate comprising an adhesive layer and a release layer, wherein the release layer comprises the release agent according to any one of claims 1 to 4. An adhesive laminated tape in which an adhesive layer of an adhesive laminate comprising an adhesive layer and a release layer is provided on at least one surface of a substrate so as to be in contact with the substrate, wherein the release layer is provided. A pressure-sensitive adhesive laminated tape comprising the release agent according to any one of the above. A pressure-sensitive adhesive laminated tape in which a substrate, a release layer, a pressure-sensitive adhesive layer and a pressure-sensitive adhesive layer substrate are laminated in this order, wherein the release layer comprises the release agent according to any one of claims 1 to 4. An adhesive laminated tape characterized by the above-mentioned.