TWI443172B - Adhesive and adhesive film - Google Patents

Description

Adhesive and adhesive film

The present invention relates to an adhesive and an adhesive film. The adhesive of the present invention can be suitably used for an adhesive film particularly for protecting the outer surface of a prismatic lens portion of a cymbal used for optical applications.

Moreover, the surface of the automobile body for protecting synthetic resin sheets (for example, for building materials), stainless steel sheets (for building materials), aluminum sheets, decorative plywood, steel sheets, glass sheets, home electric appliances, precision machinery, and manufacturing; It is used to protect articles from damage during handling in stacking, storage, transport and manufacturing steps; and to protect articles from injury during secondary processing (such as bending and pressurization).

In the past, the adhesive film for the purpose of protecting the surface of the covering is used for processing, storage, and transportation of building materials, electrical, electronic products, automobiles, etc., and the adhesive film has good adhesion and is in use. After that, the adhesive must not be contaminated on the surface and can be easily peeled off.

Such an adhesive film is formed by laminating an adhesive layer on a layer as a substrate. The method for producing the adhesive film may, for example, be a method of applying a solution-like adhesive to a base material layer made of a synthetic resin or the like; and extruding the base material layer and the adhesive layer from a plurality of extruders. A method of co-extruding a film using a T-die or the like is used. Among these, in terms of cost and quality, co-extrusion film formation using the T-die method is superior.

In the case of performing a co-extrusion film formation, a useful resin for the adhesive layer is a styrene-based elastomer which is one of thermoplastic elastomers. The styrene-based elastic system is excellent in the adhesion of the adhesive layer to the base material layer containing the polyolefin-based resin, and has an advantage that the adhesion is easily controlled by adding the adhesion-imparting agent (Patent Document 1).

In addition, in recent years, the above-mentioned covering body is diversified, and the covering surface is not only smooth, but also many surface irregularities can be seen. The covering body having the surface unevenness may, for example, be a prismatic lens portion used for a cymbal sheet of an optical member, and for a covering body having surface irregularities such as a cymbal sheet, it is necessary to exhibit sufficient adhesive force in use. .

Therefore, there are the following considerations: to improve the adhesion of the adhesive layer in a manner that the adhesion is small even if the contact area is small, or to increase the adhesion of the adhesive layer to the surface of the coated body by softening the adhesive layer. Contact area to get adhesion and so on.

In order to improve the self-adhesiveness of the adhesive layer, it is possible to add an adhesive-imparting resin to a styrene-based elastomer suitable for the adhesive layer (see, for example, Patent Document 1). However, when an excessive adhesion-imparting resin is added to the styrene-based elastomer, and the formed adhesive layer is coextruded by an extruder and laminated on the base material layer, the melt viscosity of the adhesive layer is lowered and the base material layer is formed. It is difficult to extend and time consuming. Further, when the adhesive layer is used for laminating, after the adhesive layer is stretched to the base material layer, since the adhesive layer has a lower melt viscosity than the base material layer, the adhesive layer is gradually formed at the end portion in the film width direction. The wrap is generated in the ground so that there is only an adhesive layer at the end portion, which causes a problem that the film end portion adheres to the film forming machine or the like.

In addition, by adding an adhesive-imparting resin to the styrene-based elastomer, the self-adhesive force necessary for the use of the enamel sheet can be exhibited (for example, see Patent Document 2), but only the styrene-based elastomer is added with adhesion. In the case of a resin, the film is brought into a roll state, and when the film is subsequently taken up, the unwinding property is not necessarily good.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. Hei 10-151656

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2007-332329

The problem to be solved by the present invention is to provide a method of coextruding an adhesive and a substrate layer with a resin using an extruder in the production of an adhesive film, and to laminate the adhesive on the substrate layer without causing insufficient expansion. Further, in the case of a film roll, the number of blocking is small, and for example, it can be suitably used for an adhesive or an adhesive film of a adherend such as a ruthenium having a small contact area with the adhesive film.

As a result of intensive studies by the inventors of the present invention, it has been found that the above problems can be solved by making the resin composition constituting the adhesive within a predetermined range, and the present invention has been completed.

In other words, the present invention is an adhesive resin composition containing 2 parts by weight or more and less than 10 parts by weight of the adhesion-imparting resin and 2 parts by weight or more based on 100 parts by weight of the styrene-based elastomer. a resin composition of a polyolefin-based resin of less than 10 parts by weight; the styrene-based elastomeric system has a styrene component of 5 to 15% by weight, and block copolymerization of a styrene-based polymer block and an olefin-based polymer block a block copolymer of a styrene polymer block and a random copolymer block of styrene and an olefin, and/or a hydride as a main component; the adhesive resin composition is characterized in particular The content of the polyolefin resin.

According to the present invention, when the adhesive film is produced, even if the adhesive and the base material layer are coextruded with a resin using an extruder, it is possible to laminate the adhesive on the base material layer without causing insufficient expansion. Adhesive film.

Further, the adhesive film of the present invention is characterized in that the adhesive resin composition is one layer of the base material layer containing the polypropylene resin as a main component.

The adhesive film of the present invention is used as a protective film. For example, even if it is applied to a coated body having surface irregularities such as a crepe sheet, it has a practically sufficient adhesive force, and even if the adhesive films are overlapped, the adhesion between the adhesive films is also adhered. Less advantage.

Moreover, it is preferable that the base material layer containing the polypropylene resin as a main component is laminated on the surface opposite to the adhesive layer containing the adhesive resin composition and the release layer.

Further, the base material layer containing the polypropylene resin as a main component, the adhesive layer containing the adhesive resin composition, and the release layer are preferably laminated by co-extrusion.

Further, the styrene-based elastomer in the above-mentioned adhesive layer preferably has a melt flow rate (MFR) of from 2.30 to 10 g/10 minutes at 230 ° C and 2.16 kgf.

Further, the polypropylene resin in the base material layer is preferably 1.0 to 15 g/10 min at 230 ° C and a melt flow rate (MFR) of 2.16 kgf.

Further, it is preferable that the adhesive film is coated with a crepe sheet.

Further, the adhesive film is preferably self-adhesive.

The adhesive layer of the present invention is capable of laminating an adhesive on a substrate layer without excessive stretching in the case of coextrusion using an extruder, and has an adhesion between the adhesive films even if the adhesive films are overlapped. The advantage of bonding is also small.

The adhesive film of the present invention is useful, for example, when it is adhered to a adherend having a small contact area with a film such as a crepe sheet as a protective film, and has sufficient adhesive force.

[Formation for implementing the invention]

Hereinafter, embodiments of the adhesive and the adhesive film of the present invention will be described. In the present invention, the term "as a main component" means that the component is 90% by mass or more.

(adhesive resin composition)

The resin composition constituting the adhesive of the present invention is obtained by mixing a styrene-based elastomer, an adhesive-imparting resin, and a polyolefin-based resin at a predetermined ratio, and is laminated by co-extrusion. When the propylene-based resin is used as the main component of the base material layer, the ductility is good, and when the layer is laminated by the feed block method, the adhesive layer is less likely to be wrapped at the end portion in the width direction of the film. It is preferred that the adhesive film exhibits adhesion to the self-adhesive body.

(styrene elastomer)

Examples of the styrene-based elastic system include styrene-butadiene-styrene, styrene-isoprene-styrene, styrene-ethylene/butene copolymer-styrene, and styrene-ethylene/propylene copolymer. - AB type of ABA type block polymer such as styrene, styrene-butadiene, styrene-isoprene, styrene-ethylene/butene copolymer, styrene-ethylene/propylene copolymer, etc. A styrene-based random copolymer such as a block copolymer or a styrene-butadiene rubber, and the like.

The hydride of the styrene-based elastomer used in the present invention means that the double bond derived from the conjugated diene of the above styrene-based elastomer is partially or completely saturated by hydrogenation. In terms of saturation, it is preferably 80 mol%, more preferably 90 mol% or more, and particularly preferably 95 to 100 mol%. When the saturation is less than 80 mol%, the weather resistance and heat resistance of the adhesive layer may be insufficient.

The styrene component in the styrene-based elastomer is preferably 5% by weight or more and 15% by weight or less. When it is less than 5% by weight, the granulation system in the case of producing a resin becomes difficult, and when it is more than 15% by weight, the adhesive force is lowered and it is difficult to obtain a necessary adhesive force. Further, the adhesion can be improved by increasing the amount of adhesion imparted to the resin, but as the amount of addition increases, the ductility of the adhesive layer during coextrusion deteriorates. When the layer is laminated by the feed block method, the adhesive layer is likely to wrap at the end portion in the width direction of the film. In order to exhibit the necessary adhesive force and to make the adhesive layer have good ductility during coextrusion, and the adhesive layer is not easily wrapped in the end portion in the width direction of the film, the styrene component in the styrene elastomer is 10 weights. More than 13% by weight or less is preferred.

The styrene-based elastomer to be used has a melt flow rate (MFR) of 2.16 kgf at a temperature of 230 ° C and a range of 0.5 to 10 g/10 minutes, and in terms of film formability, it is 2.0 to 8.0 g/10 minutes. The range is better.

(adhesive to resin)

Examples of the adhesion-imparting resin include an aliphatic hydrocarbon resin, an aromatic hydrocarbon resin, a terpene resin, a coumarone oxime resin, a styrene resin, and a rosin resin.

The content of the adhesion-imparting resin in the resin composition is preferably 5% by weight or more and 15% by weight or less based on 100 parts by weight of the styrene component, and more preferably 2 parts by weight or more and less than 10 parts by weight. . When the content of the adhesion-imparting resin is less than 2 parts by weight, the adhesion is not expected to be improved. When the adhesion-imparting resin is excessively increased to 10% by weight or more, the melt viscosity is remarkably lowered at the time of melt extrusion.

When a polypropylene resin-based resin having a melt flow rate (MFR) of 2.16 kgf at 230 ° C and a melt flow rate (MFR) of less than 15 (g/10 min) is used as a base material layer, and an adhesive layer having a low melt viscosity is deposited by co-extrusion, The difference in melt viscosity between the layer and the adhesive layer creates the problem that the adhesive layer is difficult to stretch and time consuming for the substrate layer. Moreover, when the adhesive layer is used to laminate, after the adhesive layer is extended to the base material layer, since the adhesive layer has a lower melt viscosity than the base material layer, the adhesive layer is slowly formed in the end portion of the film width direction. There is a problem in that the end portion has only an adhesive layer and the film end portion is adhered to the film forming machine or the like. Further, after the adhesive film is wound into a roll shape, there is a problem that adhesion tends to occur when it is rolled up again. Also, because there is also the possibility of contaminating the covering. The content of the adhesion-imparting resin is preferably 4% by weight or more and 9% by weight or less.

(polyolefin resin)

The polyolefin resin is not particularly limited, and examples thereof include crystalline polypropylene, a copolymer of propylene and a small amount of α-olefin, low density polyethylene, high density polyethylene, a copolymer of ethylene and a small amount of α-olefin, and ethylene. Copolymer with vinyl acetate and the like. In addition, since the base material layer is composed of a polypropylene resin, the polypropylene resin can be suitably used in terms of the relationship of the melt viscosity and the like.

The polyolefin resin to be used has a melt flow rate (MFR) of 2.16 kgf at 230 ° C, preferably in the range of 0.5 to 10 g/10 min, and 2.0 to 8.0 g/10 min based on the film forming property. The range is better.

The content of the polyolefin-based resin in the resin composition is from 5% by weight to 15% by weight based on 100 parts by weight of the styrene component, and is 2 parts by weight or more and less than 10 parts by weight. range. When the amount is more than 10 parts by weight, the adhesive strength is low, and sufficient adhesion to the covering having surface unevenness is not obtained, and the ductility is also poor. When the amount is less than 2 parts by weight, the film is stored in a roll state, and when the film is wound up, there is also a problem that adhesion occurs and the film partially elongates or deforms. The content of the polyolefin resin is preferably 4% by weight or more and 9% by weight or less.

Further, the adhesive-imparting resin used in the adhesive sometimes contains a part of the powder depending on the type, and sometimes contaminates the extruder at the time of extrusion. Since such a problem can be improved by using a binder-forming resin and a polyolefin-based resin to be used as a master batch, it is preferred to use a binder-imparting resin and a polyolefin-based resin as a master batch.

In the adhesive used in the present invention, a crosslinking agent, an adhesion-imparting agent, an inorganic or organic filler, a softener, a plasticizer, and a surfactant may be added as needed in order not to hinder the achievement of the problem of the present invention. One or more kinds of various additives, such as a coupling agent, an antifoaming agent, an antistatic agent, and a flame retardant, to select an additive which does not inhibit the transparency of the adhesive layer and the obtained adhesive film (surface protective film) And use is better.

(adhesive film)

An adhesive film in which an adhesive layer is laminated on a base material layer containing a polypropylene resin as a main component by using an adhesive as an adhesive layer, and the adhesive layer can be sufficiently extended on the substrate layer. . Further, it has a sufficient adhesion to a coating system such as a crepe sheet, and has an advantage that the adhesion between the adhesive films is small even if the adhesive films overlap each other.

The adhesive film of the present invention has an adhesive force at 23 ° C, and is preferably in the range of 3 to 50 cN / 25 cm for the enamel sheet based on the protective properties of the enamel sheet. When the adhesive force is less than 3 cN/25 cm, curling or the like is generated when the cymbal is protected, and the function as a protective film cannot be performed. On the other hand, when the adhesive force is more than 50 cN/25 cm, when the film is peeled off from the enamel sheet, there is a possibility that the film cannot be smoothly peeled off. The adhesive force can be appropriately set by changing the resin composition and thickness of the adhesive layer.

The peeling force of the adhesive film of the present invention to the release surface is preferably in the range of 100 cN/25 cm or less at 23 ° C, and is preferable because the film is rolled out in the form of a roll. When the peeling force is more than 100 cN/25 cm, the film is unwound when the adhesive film is in the form of a roll, which causes a problem that the film is partially elongated or deformed. The peeling force can be appropriately set by changing the contact area between the adhesive surface and the release surface when the roll is formed into a roll by forming the surface unevenness in the release layer. Further, by adding a resin having an effect of lowering the surface free energy such as a fluororesin, a polyoxymethylene resin, or a 4-methyl-1-pentene polymer to the release layer, the peeling force can be reduced.

The adhesive film of the present invention can be made to contain a well-known additive as needed. For example, it may contain a lubricant, an anti-adhesive agent, a thermal stabilizer, an antioxidant, an antistatic agent, a light stabilizer, an impact modifier, and the like.

However, it is preferred that the low molecular weight substance on the surface of the adhesive layer be less than 1 mg/m ² . Here, the measurement of the low molecular weight substance on the surface of the adhesive layer was carried out in the following order. After washing the surface of the adhesive layer with an organic solvent such as ethanol which does not erode the resin constituting the adhesive layer, the organic solvent or the like is removed from the cleaning liquid using an evaporator or the like, and the residue is weighed to divide the obtained value by the adhesion. The surface area of the layer surface is obtained.

Here, when the residue is present at 1 mg/m ² or more, foreign matter is present between the surface of the adhesive layer and the surface of the adherend, because the contact area is reduced and the van der Waals force is lowered, so the adhesive force is low, but it is not good. When an additive is added, it is necessary to select an additive such as a polymer type, or to check the amount of addition, the method of addition, and the like so as not to migrate or transfer to the adhesive layer.

(base material layer)

The adhesive film of the present invention requires a base material layer containing a polypropylene resin as a main component. The polypropylene-based resin used herein may, for example, be a crystalline polypropylene, a random copolymer of propylene and a small amount of an α-olefin, or a block copolymer. In addition, the crystallized polypropylene-based resin is an isotactic heptane-insoluble isotactic polypropylene homopolymer used in ordinary extrusion molding or the like, or 60% by weight. The above copolymer of propylene and other α-olefins, and the propylene homopolymer or a copolymer of propylene and another α-olefin can be used singly or in combination.

Here, the term "n-heptane-insoluble" is used as an indicator of the crystallinity of polypropylene and at the same time, and it is safe. In the present invention, it is suitable for the use of the Japanese Ministry of Health, Welfare, and the Ministry of Health and Welfare No. 20 in February (1982). The heptane is insoluble (it is preferable that the eluted portion at the time of extraction at 60 ° C and 60 minutes is 150 ppm or less [the use temperature is 30 ppm or less in a case where the temperature is more than 100 ° C).

The α-olefin copolymerization component of the copolymer of propylene and another α-olefin is an α-olefin having 2 to 8 carbon atoms, for example, ethylene or 1-butene, 1-pentene, 1-hexene An α-olefin of C4 or higher, such as an alkene or 4-methyl-1-pentene, is preferred.

Here, the copolymer is preferably a random or block copolymer obtained by polymerizing one or two or more kinds of the above-exemplified α-olefins with propylene.

For the above reasons, the polypropylene resin to be used has a melt flow rate (MFR) of 2.16 kgf at 230 ° C, preferably in the range of 1.0 to 15 g/10 min, and in the range of 2.0 to 10.0 g/10 min. good.

Further, it is also possible to use two or more kinds of copolymers of propylene and another α-olefin.

Further, the waste film produced when the film obtained in the present invention is processed in a product can be regranulated as a raw material to be recovered and added to the substrate layer. By using recycled raw materials, production costs can be suppressed.

The ductility of the adhesive layer in the adhesive film of the present invention to the substrate layer is preferably 90% or more. If the adhesive layer has low ductility, it takes a lot of time to replace the resin and the workability is deteriorated. Further, when the adhesive layer is laminated on the order of several μm, there is a problem that thickness unevenness tends to occur in the width direction of the film. The ductility of the adhesive layer is preferably 90% or more, more preferably 93% or more, and particularly preferably 95% or more.

In the adhesive film of the present invention, the adhesion ratio of the adhesive layer to the substrate layer is preferably 3% or less, and when the encapsulation ratio of the adhesive layer is high, only the adhesive layer is present at the end portion of the film, and adhesion to the film forming machine occurs. The problem caused the operability to deteriorate. The wrap ratio of the adhesive layer to the substrate layer is preferably 2.5% or less.

The thickness of the adhesive layer of the adhesive film of the present invention is preferably 1 μm or more and less than 30 μm. When the thickness of the adhesive film is less than 1 μm, it is difficult to form a film stably by co-extrusion, and when it is 30 μm or more, it is a film which is disadvantageous in terms of cost. At this time, when the adhesion is increased, it is preferable to increase the thickness in consideration of the viscosity. By increasing the thickness of the adhesive layer, the contact area with the adherend tends to become large. The thickness of the adhesive layer is preferably 2 μm or more and 20 μm or less, more preferably 3 μm or more and 15 μm or less, and particularly preferably 4 μm or more and 8 μm or less.

The thickness of the base material layer of the adhesive film of the present invention is preferably 5 μm or more and less than 100 μm, more preferably 15 μm or more and less than 25 μm. When the thickness of the adhesive film is less than 5 μm, the toughness is weak, and when the coated body is used as a protective film, wrinkles are likely to occur and the adhesive force is not sufficiently obtained. When the thickness is 100 μm or more, the film is disadvantageous in terms of cost.

(release layer)

In the adhesive film of the present invention, it is preferred to form a release layer on the surface opposite to the adhesive layer laminated on one surface of the substrate layer. By doing so, the adhesion can be further suppressed. In view of the resin composition of the adhesive layer of the present invention, the average surface roughness SRa of the surface of the release layer is preferably 0.40 μm or more. The surface having an average surface roughness SRa of 0.850 μm or less is preferable, and particularly preferably 0.500 μm or more and 0.700 μm or less. The thickness of the release layer is preferably 1 μm or more and less than 30 μm, and particularly preferably 3 to 10 μm.

In order to form the surface unevenness as described above, a layer having a rough matte shape and a rough surface can be formed by using a propylene-ethylene block copolymer. Further, the same effect can be expected by mixing a polyethylene resin in the homopolypropylene. Further, a layer having a rougher surface can be formed by mixing a polyethylene-based resin in the propylene-ethylene block copolymer. Specifically, a propylene-ethylene block copolymer such as "BC4FC" manufactured by Japan POLYPRO Co., Ltd. can be exemplified as the resin which is suitable for obtaining a surface having a rough matte shape.

In operation, the adhesive film of the present invention is suitably in the form of a roll. The width of the film roll and the upper limit of the winding length are not particularly limited, and the width is usually 1.5 m or less based on the ease of handling, and when the film thickness is 30 μm, the winding length is preferably 6000 m or less. Further, a plastic core and a metal core of 3 inches, 6 inches, and 8 inches are usually used as the winding core. Moreover, it is preferable to use a film roll which is wound up by a length of 200 m or more and a width of 450 mm or more from the viewpoint of processing suitability.

In order to protect the outer surface of the prismatic lens portion of the cymbal used for optical use, an adhesive film using the adhesive of the present invention can be suitably used. Moreover, in order to protect synthetic resin sheets (for example, for building materials), stainless steel sheets (for building materials), aluminum sheets, decorative plywood, steel sheets, glass sheets, home appliances, precision machinery, and the surface of automobile bodies at the time of manufacture; Protect articles from injury during handling in stacking, storage, transport, and manufacturing steps; and protect articles from injury during secondary processing (such as bending and pressurization).

[Examples]

The invention will be further illustrated by the following examples. However, the invention is not limited by the following examples, without departing from the gist of the invention. Moreover, the evaluation methods of the physical properties of the following examples and comparative examples are as follows.

(1) Evaluation of the ductility of the adhesive layer to the substrate layer

In a 3-layer T-die (feed block type, lip width 850 mm, lip gap 1 mm), the adhesive layer resin was discharged at a rate of 15 kg/hr using a 40 mm Φ single-axis extruder; using a 90 mm Φ uniaxial extrusion The substrate layer resin was discharged at a rate of 15 kg/hour; and the release layer resin was coextruded at a discharge rate of 5 kg/hour using a 60 mm Φ single-axis extruder. An unstretched film having a width of 650 mm was obtained by drawing the extruded film at a speed of 20 m/min to a casting drum having a temperature of 30 °C. The adhesive layer resin was placed in a 40 mm Φ single-axis extruder, and the elongation of the adhesive layer to the substrate layer after 30 minutes from the start of the replacement of the resin was measured.

Extensibility = thickness of the adhesive layer (mm) / 650 (mm) × 100 (%)

(2) Evaluation of the wrap property of the adhesive layer on the substrate side

In a 3-layer T-die (feed block type, lip width 850 mm, lip gap 1 mm), the adhesive layer resin was discharged at a rate of 15 kg/hr using a 40 mm Φ single-axis extruder; using a 90 mm Φ uniaxial extrusion The substrate layer resin was discharged at a rate of 15 kg/hour; and the release layer resin was coextruded at a discharge rate of 5 kg/hour using a 65 mm Φ single-axis extruder. An unstretched film having a width of 650 mm was obtained by drawing the extruded film at a speed of 20 m/min to a casting drum having a temperature of 30 °C. The adhesive layer resin was placed in a 40 mm Φ single-axis extruder, and the wrap ratio of the adhesive layer to the both ends in the film width direction of the base material layer after 120 minutes from the replacement of the resin was measured.

Wrap ratio = width (mm) / 650 (mm) × 100 (%) of the adhesive layer wrapped at both ends in the width direction of the film

(3) Evaluation of adhesion

According to JIS-Z-0237 (2000) Adhesive tape ‧ adhesive sheet test method and measured by the following method.

Prepare acrylic sheets (made by Mitsubishi Rayon Co., Ltd.: Acrylight (registered trademark) 3mm thick) 50mm × 150mm, two types of cymbals in different surface treatment conditions (the lens part is composed of triangular prisms, the height of the triangular column is 25μm, triangular prism The width is 50 μm) 50 mm × 150 mm as the adherend, and a test piece of 150 mm in the winding direction at the time of film production and 25 mm in the direction orthogonal thereto is cut out as a test piece, and a rubber roll having a mass of 2000 g (roll surface) is used. The spring hardness was 80 Hs, the width of the rubber layer covered with a thickness of 6 mm was 45 mm, and the diameter (including the rubber layer) was 95 mm. The material was rubbed once at a speed of 5 mm/sec to adhere the adherend to the test piece. After the pressure-bonding, the product was placed at a temperature of 23 ° C and a relative humidity of 65% for 30 minutes, and "AUTOGRAPH (registered trademark)" (AGS-J) manufactured by Shimadzu Corporation was used at a rate of 300 mm/min. The resistance value at 180 degree peeling was used as the adhesive force [cN/25 cm]. The 180-degree peeling means that the peeling angle of the acrylic sheet and the film is maintained at 180 degrees when the resistance value at the time of peeling is measured.

A polyester sheet having a thickness of 190 μm and a size of 25 mm×170 mm was prepared as a grip portion for a measurement sample at the time of measurement, and a sticky layer was used on the end portion of the adhesive film of the measurement sample in which the adhesive film and the acrylic sheet were pressure-bonded. The rubber portion was adhered to a Cellophane Tape (registered trademark) having a width of 15 mm and used as a grip portion at the time of measurement. A schematic diagram of the measurement sample is shown in Fig. 1. The measurement was performed three times on one sample, and the average value was used as the adhesion of the sample.

(4) Evaluation of adhesion resistance

The peeling force of the release layer and the adhesive layer of the adhesive film was measured as the evaluation of the adhesive resistance as follows.

A double-sided adhesive tape (made by Nitto Denko Co., Ltd.: No. 535A) was attached to the entire surface of an acrylic sheet (Mitsubishi Rayon: Acrylight 3 mm thick) 50 mm × 150 mm, and the tape was additionally attached on both sides. On one side, a test piece of 150 mm (winding direction at the time of film production) × 50 mm (direction orthogonal to the winding direction at the time of film production) was adhered to the test piece.

A test piece of 150 mm in the winding direction at the time of film production and 25 mm in the direction orthogonal thereto was cut out as a new test piece, and the adhesive face and the test piece which had been passed through the double-sided adhesive tape on the acrylic plate were cut out. After the release faces were overlapped, a rubber roller having a mass of 2000 g was used (the spring type hardness of the roll surface was 80 Hs, the width of the rubber layer covered with a thickness of 6 mm was 45 mm, and the diameter (including the rubber layer) was 95 mm) was 5 mm/ The speed of the second makes it reciprocate once and the release surface is pressed against the test piece. After the pressure-bonding, the product was placed at a temperature of 23 ° C and a relative humidity of 65% for 30 minutes, and "AUTOGRAPH (registered trademark)" (AGS-J) manufactured by Shimadzu Corporation was used at a rate of 300 mm/min. The resistance value at 180 degree peeling was taken as the peeling force [cN/25 mm].

A polyester sheet having a thickness of 190 μm and a size of 25 mm × 170 mm was prepared as a grip portion for measuring a sample at the time of measurement, and a Cellophane Tape (registered trademark) having a 15 mm-width adhesive portion was used at the end portion of the test piece of 150 mm × 25 mm. Adhesively used as a gripping part for measurement. The measurement was carried out three times for one sample, and the average value thereof was taken as the peeling force of the sample.

(5) Determination of average surface roughness

The contact center three-dimensional surface roughness meter (type ET-30HK) manufactured by Otaru Research Institute Co., Ltd. was used to measure the center-surface average roughness (SRa) of the surface of the release layer by the stylus method and using the following conditions. . The conditions are as follows, and the average value of the three measurements is taken as the value.

Tip end radius: 0.5μm

Stylus pressure: 20mg

Cutoff: 80μm

Measuring length: 1000μm

Measurement speed: 100 μm / sec

Measurement interval: 2μm

(6) Operational

When the obtained film was a roll, the film resistance when the film was taken up from the roll was evaluated as ○, and the larger one was ╳.

[Example 1] (Manufacture of substrate layer)

100 wt% of a polypropylene resin (manufactured by Sumitomo Chemical Co., Ltd., FS2011DG3, MFR: 2.5 g/10 min) was melt-extruded using a 90 mm Φ uniaxial extruder to obtain a base material layer.

(Manufacture of adhesive layer)

Mixing with 100 parts by weight of a styrene-based elastomer (manufactured by Asahi Kasei Chemicals: TAFTEC (registered trademark) H1221, styrene copolymerization ratio: 12 wt%, MFR: 4.5 g/10 min) using a 40 mm Φ single-axis extruder 8.8 parts by weight of polypropylene resin (manufactured by Sumitomo Chemical Co., Ltd.: FS2011DG3, MFR: 2.5 g/10 min) and 8.8 parts by weight of petroleum resin (manufactured by Arakawa Chemical Industry Co., Ltd.: Arkon (registered trademark) P125) Adhesive layer.

(manufacturing of release layer)

100 wt% of a propylene-ethylene block copolymer (manufactured by Japan Polypropylene: BC4FC) was melt-extruded as a release layer using a 65 mm Φ single-axis extruder.

(manufacturing of film)

The substrate layer, the adhesive layer, and the release layer were directly melted in each extruder using a three-layer T-die (a supply block type, a lip width of 850 mm, and a lip gap of 1 mm) at 250 ° C. Laminated and extruded. The extruded film was drawn at a speed of 20 m/min to a casting roll having a temperature of 30 ° C, and solidified by cooling to obtain three kinds of three layers of a substrate layer thickness of 18 μm, an adhesive layer thickness of 6 μm, and a release layer thickness of 6 μm. Extend the film.

[Embodiment 2]

The adhesive layer and the release layer were maintained in the same manner as in Example 1. The base material layer was changed to the following contents, and three kinds of three-layer unstretched films were obtained by the same method as in Example 1.

(Manufacture of substrate layer)

100 wt% of the homopolypropylene resin (manufactured by Sumitomo Chemical Co., Ltd.: FLX80E4 (MFR: 7.5 g/10 min) was melt-extruded to form a substrate layer using a 90 mm Φ single-axis extruder.

[Example 3]

The base material layer and the release layer were maintained in the same manner as in Example 1. The adhesive layer was changed to the following contents, and three kinds of three-layer unstretched films were obtained by the same method as in Example 1.

(Manufacture of adhesive layer)

Using a 40 mm Φ uniaxial extruder, 3.2 parts by weight of 100 parts by weight of a styrene-based elastomer (manufactured by Asahi Kasei Chemicals: TAFTEC H1221, styrene copolymerization ratio: 12% by weight, MFR: 4.5 g/10 min) was mixed. A petroleum resin (manufactured by Arakawa Chemical Co., Ltd.: Arkon P125) and 3.2 parts by weight of a polypropylene resin (manufactured by Sumitomo Chemical Co., Ltd.: FS2011DG3, MFR: 2.5 g/10 min) were melt-extruded to form an adhesive layer.

[Example 4]

The base material layer and the release layer were maintained in the same manner as in Example 1. The adhesive layer was changed to the following contents, and three kinds of three-layer unstretched films were obtained by the same method as in Example 1.

(Manufacture of adhesive layer)

8.8 parts by weight with respect to 100 parts by weight of a styrene-based elastomer (manufactured by Asahi Kasei Chemicals: TAFTEC H1221, styrene copolymerization ratio: 12% by weight, MFR: 4.5 g/10 min) was mixed using a 40 mm Φ single-axis extruder. A petroleum resin (manufactured by Arakawa Chemical Co., Ltd.: Arkon P125) and 8.8 parts by weight of a polypropylene resin (manufactured by Sumitomo Chemical Co., Ltd.: WF836DG3, MFR: 7.0 g/10 min) were melt-extruded to form an adhesive layer.

[Example 5]

The release layer was maintained in the same manner as in Example 1. The base material layer and the pressure-sensitive adhesive layer were changed to the following contents, and three kinds of three-layer unstretched films were obtained by the same method as in Example 1.

(Manufacture of adhesive layer)

5.7 parts by weight with respect to 100 parts by weight of a styrene-based elastomer (manufactured by Asahi Kasei Chemicals: TAFTEC H1221, styrene copolymerization ratio: 12% by weight, MFR: 4.5 g/10 min) was mixed using a 40 mm Φ single-axis extruder. Petroleum resin (manufactured by Arakawa Chemical Industry Co., Ltd.: Arkon P125) and 8.0 parts by weight of a polypropylene resin (manufactured by Sumitomo Chemical Co., Ltd.: FS2011DG3, MFR: 2.5 g/10 min) were melt-extruded to form an adhesive layer.

(Manufacture of substrate layer)

100 wt% of the homopolypropylene resin (manufactured by Sumitomo Chemical Co., Ltd.: FLX80E4 (MFR: 7.5 g/10 min) was melt-extruded to form a substrate layer using a 90 mm Φ single-axis extruder.

[Comparative Example 1]

The base material layer and the release layer were maintained in the same manner as in Example 1. The adhesive layer was changed to the following contents, and three kinds of three-layer unstretched films were obtained by the same method as in Example 1.

(Manufacture of adhesive layer)

With respect to 100 parts by weight of a styrene-based elastomer (manufactured by Asahi Kasei Chemicals: TAFTEC H1221, styrene copolymerization ratio: 12% by weight, MFR: 4.5 g/10 min), 17.6 parts by weight was mixed using a 40 mm Φ single-axis extruder. A petroleum resin (manufactured by Arakawa Chemical Industry Co., Ltd.: Arkon P125) was melt-extruded and used as an adhesive layer.

[Comparative Example 2]

The base material layer and the release layer were maintained in the same manner as in Example 1. The adhesive layer was changed to the following contents, and three kinds of three-layer unstretched films were obtained by the same method as in Example 1.

(Manufacture of adhesive layer)

Using a 40 mm Φ uniaxial extruder, 21.4 parts by weight of 100 parts by weight of a styrene-based elastomer (manufactured by Asahi Kasei Chemicals: TAFTEC H1221, styrene copolymerization ratio: 12% by weight, MFR: 4.5 g/10 min) was mixed. A petroleum resin (manufactured by Arakawa Chemical Co., Ltd.: Arkon P125) and 21.4 parts by weight of a polypropylene resin (manufactured by Sumitomo Chemical Co., Ltd.: FS2011DG3, MFR: 2.5 g/10 min) were melt-extruded to form an adhesive layer.

[Comparative Example 3]

The base material layer and the release layer were maintained in the same manner as in Example 1. The adhesive layer was changed to the following contents, and three kinds of three-layer unstretched films were obtained by the same method as in Example 1.

(Manufacture of adhesive layer)

With respect to 100 parts by weight of a styrene-based elastomer (manufactured by Asahi Kasei Chemicals: TAFTEC H1221, styrene copolymerization ratio: 12% by weight, MFR: 4.5 g/10 min), 17.6 parts by weight was mixed using a 40 mm Φ single-axis extruder. A polypropylene resin (manufactured by Sumitomo Chemical Co., Ltd.: FS2011DG3, MFR: 2.5 g/10 min) was melt-extruded to form an adhesive layer.

[Comparative Example 4]

The release layer was maintained in the same manner as in Example 1. The adhesive layer and the substrate layer were changed to the following contents, and three types of three-layer unstretched films were obtained by the same method as in Example 1.

(Manufacture of adhesive layer)

With respect to 100 parts by weight of a styrene-based elastomer (manufactured by Asahi Kasei Chemicals: TAFTEC H1221, styrene copolymerization ratio: 12% by weight, MFR: 4.5 g/10 min), 17.6 parts by weight was mixed using a 40 mm Φ single-axis extruder. A petroleum resin (manufactured by Arakawa Chemical Industry Co., Ltd.: Arkon P125) was melt-extruded and used as an adhesive layer.

(Manufacture of substrate layer)

100 wt% of the homopolypropylene resin (manufactured by Sumitomo Chemical Co., Ltd.: FLX80E4 (MFR: 7.5 g/10 min) was melt-extruded to form a substrate layer using a 90 mm Φ single-axis extruder.

[Comparative Example 5]

The base material layer and the release layer were maintained in the same manner as in Example 1. The adhesive layer was changed to the following contents, and three kinds of three-layer unstretched films were obtained by the same method as in Example 1.

(Manufacture of adhesive layer)

6.4 parts by weight with respect to 100 parts by weight of a styrene-based elastomer (manufactured by Asahi Kasei Chemicals: TAFTEC H1221, styrene copolymerization ratio: 12% by weight, MFR: 4.5 g/10 min) was mixed using a 40 mm Φ single-axis extruder. A petroleum resin (manufactured by Arakawa Chemical Industry Co., Ltd.: Arkon P125) was melt-extruded and used as an adhesive layer.

[Comparative Example 6]

The base material layer and the release layer were maintained in the same manner as in Example 1. The adhesive layer was changed to the following contents, and three kinds of three-layer unstretched films were obtained by the same method as in Example 1.

(Manufacture of adhesive layer)

6.3 parts by weight with respect to 100 parts by weight of a styrene-based elastomer (manufactured by Asahi Kasei Chemicals: TAFTEC H1221, styrene copolymerization ratio: 12% by weight, MFR: 4.5 g/10 min) was mixed using a 40 mm Φ single-axis extruder. A petroleum resin (manufactured by Arakawa Chemical Co., Ltd.: Arkon P125) and 18.8 parts by weight of a polypropylene resin (manufactured by Sumitomo Chemical Co., Ltd.: FS2011DG3, MFR: 2.5 g/10 min) were melt-extruded to form an adhesive layer.

[Comparative Example 7]

The base material layer and the release layer were maintained in the same manner as in Example 1. The adhesive layer was changed to the following contents, and three kinds of three-layer unstretched films were obtained by the same method as in Example 1.

(Manufacture of adhesive layer)

100 parts by weight of a styrene-based elastomer (manufactured by Asahi Kasei Chemicals: TAFTEC H1221, styrene copolymerization ratio: 12% by weight, MFR: 4.5 g/10 min) was mixed with 18.8 parts by weight using a 40 mm Φ single-axis extruder. Petroleum resin (manufactured by Arakawa Chemical Industry Co., Ltd.: Arkon P125) and 6.3 parts by weight of a polypropylene resin (manufactured by Sumitomo Chemical Co., Ltd.: WF836DG3, MFR: 7.0 g/10 min) were melt-extruded to form an adhesive layer.

[Comparative Example 8]

The base material layer and the release layer were maintained in the same manner as in Example 1. The adhesive layer was changed to the following contents, and three kinds of three-layer unstretched films were obtained by the same method as in Example 1.

(Manufacture of adhesive layer)

8.8 parts by weight with respect to 100 parts by weight of a styrene-based elastomer (manufactured by Asahi Kasei Chemicals: TAFTEC H106, styrene copolymerization ratio: 18% by weight, MFR: 4.5 g/10 min) was mixed using a 40 mm Φ single-axis extruder. Petroleum resin (Arkon P125 manufactured by Arakawa Chemical Industry Co., Ltd.) and 8.8 parts by weight of a polypropylene resin (manufactured by Sumitomo Chemical Co., Ltd.: FS2011DG3, MFR: 2.5 g/10 min) were melt-extruded to form an adhesive layer.

The above results are shown in Tables 1, 2 and 3.

As is clear from Table 1, the films obtained in Examples 1 to 5 were excellent in ductility at the time of film formation, and had practically sufficient adhesion when used as a protective film, and operation when the film became a roll. Sex is also good.

On the other hand, in the films obtained in Comparative Examples 1, 4, and 7, the ductility at the time of film formation was insufficient, and the adhesive was wrapped, which was not necessarily a result of good film formability. Further, the operability in making the film into a roll is not necessarily a good result. The films obtained in Comparative Examples 2, 3, 6 and 8 did not have practically necessary adhesion on the crepe of the covering. The film obtained in Comparative Example 5 is not necessarily a good result with respect to the workability when the film is formed into a roll. As described above, any of the films obtained in the comparative examples was inferior in quality and low in practicality.

[Industry use possibility]

The adhesive of the present invention is particularly suitable for use in an adhesive film for protecting the outer surface of a prismatic lens portion of a cymbal used for optical applications.

Moreover, in order to protect synthetic resin sheets (for example, for building materials), stainless steel sheets (for building materials), aluminum sheets, decorative plywood, steel sheets, glass sheets, home appliances, precision machinery, and the surface of automobile bodies when manufactured; Stacking, storage, transportation, and manufacturing steps are important for the industry in order to protect articles from injury, and to protect articles from damage during secondary processing (such as bending and pressurization).

Fig. 1 is a schematic view of a sample to be measured.

Claims (8)

An adhesive resin composition comprising: a resin composition containing 2 parts by weight or more and less than 10 parts by weight of an adhesion-imparting resin, and 2 parts by weight or less or less based on 100 parts by weight of the styrene-based elastomer; 10 parts by weight of a polyolefin-based resin; the styrene-based elastomeric system has a styrene component of 5 to 15% by weight, and a block copolymer of a styrene-based polymer block and an olefin-based polymer block, and a styrene-based compound A block copolymer of a polymer block and a random copolymer block of styrene and an olefin, and/or such a hydride is used as a main component. An adhesive film obtained by laminating an adhesive resin composition of the first aspect of the patent application on one surface of a base material layer containing a polypropylene resin as a main component. An adhesive film according to claim 2, which is formed by laminating a release layer on a surface of a base material layer containing a polypropylene resin as a main component opposite to an adhesive layer containing an adhesive resin composition. An adhesive film according to claim 3, which is obtained by co-extruding a base material layer containing a polypropylene resin as a main component, an adhesive layer containing an adhesive resin composition, and a release layer. The adhesive film of claim 2, wherein the styrene elastomer in the adhesive layer has a melt flow rate (MFR) of 230 to 10 g/10 minutes at 230 ° C and 2.16 kgf. The adhesive film of claim 2, wherein the polypropylene resin in the substrate layer has a melt flow rate (MFR) of 2.15 to 15 g/10 minutes at 230 ° C and 2.16 kgf. For example, in the adhesive film of claim 2, the adhesive film is coated. An adhesive film according to any one of claims 2 to 7, which is self-adhesive.