JPH10219203A - Adhesion tape - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an adhesion tape good in cutting property with hand, and also suppressing an elongation in longitudinal direction thereof. SOLUTION: This adhesion tape contains a base film layer 1 made from an un-stretched polyolefin resin and formed as a flat smooth surface in one surface and a nonflat smooth surface having recessed parts as parallel notches having 0.03-0.3mm depth and 0.5-5mm interval, crossing rectangularly to the longitudinal direction of the adhesion taps in another surface, a reinforcing film layer 2 and an adhesive layer 3, and film layers thereof is adhered each other with an adhesive having <=70% elongation rate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an adhesive tape. More specifically, the present invention relates to an unstretched polyolefin resin base having one surface formed on a smooth surface and the other surface formed on a surface having a specific recess (hereinafter, the surface having a recess is referred to as a “non-smooth surface”). The present invention relates to a pressure-sensitive adhesive tape comprising a material film layer, a reinforcing film layer, and a pressure-sensitive adhesive layer, which has good hand-cutting properties and suppresses longitudinal elongation.

[0002]

2. Description of the Related Art As shown in FIG. 8, an adhesive tape generally comprises a thin base material 101 made of resin, paper, cloth, or the like, and an adhesive 102 applied on the base material. It is commercially available in the form of rolled up in a roll, and the adhesive tape is drawn out (deployed) to the required length from the roll,
Cut and use at desired locations.

[0003] Japanese Patent Laid-Open Publication No. 3-47885 discloses FIG.
And a pressure-sensitive adhesive layer 106 applied on the non-smooth surface 104 of the base film 105, the base film 105 having one surface formed on the smooth surface 103 and the other surface formed on the non-smooth surface 104. Adhesive tapes are described. The base film 105 of the adhesive tape is made of a polyolefin resin, and the non-smooth surface 104 is a surface having a concave portion 107 that is a notch parallel line perpendicular to the longitudinal direction of the adhesive tape.

[0004]

The roll-shaped pressure-sensitive adhesive tape described in the above publication uses a cutting tool such as a sawtooth-shaped cutter or scissors generally used for cutting a commercially available cellotape (registered trademark). Although it is possible to cut the adhesive tape straight in the width direction easily with only the hand (fingertip) without using it (the adhesive tape having such a cutting property is referred to as "adhesive tape having good hand-cutting properties"). When an external force is applied in the longitudinal direction, for example, when a roll-shaped pressure-sensitive adhesive tape is developed to a required length, the adhesive tape is easily stretched in the longitudinal direction, and there is a demand for an improvement in that the stretch in the longitudinal direction is reduced. Was. Here, the property that the adhesive tape is easy to stretch in the longitudinal direction is the property that the adhesive tape shrinks easily after the adhesive tape is attached to the adherend. In the case of using an adhesive tape for coating (masking in painting), there may be a problem that it is difficult to clarify the boundary of the coating film.

An object of the present invention is to provide a pressure-sensitive adhesive tape which has good hand-cutting properties and suppresses elongation in the longitudinal direction.

[0006]

DISCLOSURE OF THE INVENTION The present inventors have developed a pressure-sensitive adhesive tape having good hand-cutting properties, wherein a film having one surface formed into a smooth surface and the other surface formed into a specific non-smooth surface is used as a base film layer. In addition, intensive studies have been made on the development of the pressure-sensitive adhesive tape in which the elongation in the longitudinal direction is suppressed. As a result, it has been found that by providing a reinforcing film layer bonded with a specific adhesive as a further layer, it is possible to obtain a pressure-sensitive adhesive tape having good hand-cutting properties and suppressing longitudinal elongation. Was completed.

That is, according to the present invention, one surface has a smooth surface and the other surface has a depth of 0.03 m perpendicular to the longitudinal direction of the adhesive tape.
an unstretched polyolefin resin base film layer formed on a non-smooth surface having a concave portion formed by a notch parallel line having a distance of 0.5 mm to 5 mm and an interval of 0.5 mm to 5 mm, a reinforcing film layer, and an adhesive layer , Wherein the film layers are joined to each other with an adhesive having an elongation of 70% or less.

Hereinafter, the present invention will be described in detail.
When the present invention is described with reference to the drawings, what is illustrated is merely an example of the present invention, and the present invention is not limited to the illustrated one. Also, the figures focus on drawing the invention in an easy-to-understand manner, and the scales do not necessarily accurately reflect actual ones.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 illustrates a perspective view of an adhesive tape of the present invention. The pressure-sensitive adhesive tape of this figure is composed of a base film layer 1, a reinforcing film layer 2, and a pressure-sensitive adhesive layer 3 from the bottom of the figure. The lowermost base film layer 1 is made of an unstretched polyolefin resin, and one surface thereof is a smooth surface 4.
(The lower surface of the figure, the surface is not visible in the figure)
On the other hand, the other surface is formed as a non-smooth surface 6 having a concave portion 5 which is a specific notch parallel line perpendicular to the longitudinal direction of the adhesive tape. The base film layer 1 and the reinforcing film layer 2 are joined with a specific adhesive described later.

[0010] The unstretched polyolefin resin base film layer of the pressure-sensitive adhesive tape of the present invention can be produced from a known polyolefin resin. The type of the polyolefin resin is not particularly limited, and examples thereof include a polyethylene resin, a polypropylene resin, a copolymer resin of ethylene and propylene, and a copolymer resin of ethylene and / or propylene and one or more other α-olefins. And α-olefins such as butene-1 and pentene-
1, hexene-1, heptene-1, octene-1, nonene-1, 4-methylpentene-1, decene-1 and the like. The preferred polyolefin resin is a polyethylene resin. The molecular weight of the polyolefin resin is not particularly limited as long as it is within the range that can be formed into a film,
When represented by a melt index, which is a measure of resin flowability, it is generally in the range of 0.2 g to 20 g / 10 min, preferably 1 g to 10 g / 10 min (load 2.16 kg, temperature 190 ° C.).

As shown in FIG. 2, the base film 1 has one surface formed on a smooth surface 4 and the other surface formed on a non-smooth surface 6 having a concave portion 5 which is a specific notch parallel line perpendicular to the longitudinal direction of the adhesive tape. It is a film, and the concave portions 5 are for imparting hand-cutting properties to the adhesive tape. The depth D of the recess 5 is 0.
03 mm to 0.3 mm, preferably 0.04 mm to 0.3 mm.
12 mm. When the depth D is less than 0.03 mm, the tensile strength in the longitudinal direction of the pressure-sensitive adhesive tape is large, but the hand-cutting property is unsatisfactory. When the depth D is more than 0.3 mm, the tensile strength in the longitudinal direction is small, but the tensile strength in the longitudinal direction is small, When the depth is extremely large, the adhesive tape may be cut at an unexpected location when unfolding from the roll. The interval W between the notch parallel lines is 0.5 mm or more from the viewpoint of obtaining an adhesive tape having good hand-cutting properties.
5 mm, preferably 0.6 mm to 1.4 mm.

The thickness T of the substrate film according to the pressure-sensitive adhesive tape of the present invention may be appropriately determined depending on the use and the like.
It is in the range of 0 μm to 400 μm. The difference (TD) between the thickness T and the depth D is generally 10 μm to 100 μm from the viewpoint of obtaining an adhesive tape with good hand-cutting properties.
Since the notch parallel lines relating to the base film are for imparting hand-cutting properties, they are not limited to the buoy (V) -shaped valley shape illustrated in FIG. 1 and the like. The shape may be U-shaped. The former form is a preferable form from the viewpoint that the cut surface after cutting the adhesive tape by hand is good. The buoy (V) valley shape illustrated in FIG. 1 and the like is a valley connected continuously from one end to the other in the width direction of the adhesive tape, but even if a part of the valley is discontinuous. Good.

FIG. 3 shows an example of a method for producing a base film having one surface formed into a smooth surface and the other surface formed into a non-smooth surface by using the polyolefin resin as a raw material. After the molten polyolefin resin 11 is formed by an extruder 12 into an extruded film, the extruded film having a temperature that can still be embossed is formed into a rubber roll 13 having a smooth surface and a squeezing roll 14 having a non-smooth surface. Pass between. Here, the rubber roll 13 is a roll having a shape corresponding to a smooth shape to be provided on one surface of the base film, and the squeezing roll 14 is a squeezing roll corresponding to a non-smooth shape to be provided on the other surface of the base film. A roll having a shape on its surface. Accordingly, by pressing the extruded film through the gap between the rubber roll 13 and the squeezing roll 14, the squeezing of the squeezing roll 14 is transferred to the surface of the extruded film, and the base film according to the present invention is obtained. Such patterning with a roll is called embossing (embossing).
This is a well-known processing method as one of the roll processing.

The electrode 15 and the processing roll 16 having a smooth surface shown in FIG. 3 have an affinity between the surface of the substrate film and an adhesive or a pressure-sensitive adhesive, which will be described later. And corona discharge treatment of the surface of the substrate film in order to increase the wetting tension of the surface of the substrate film. In this case, since the non-smooth surface of the base film is opposed to the electrode 15 side, the non-smooth surface is subjected to corona discharge treatment. In addition, as another method for increasing the affinity between the base film and the adhesive or the pressure-sensitive adhesive, a primer treatment can be exemplified.

Although corona discharge treatment and primer treatment are well-known treatment methods in the field of pressure-sensitive adhesive tapes, these treatments are not essential in the present invention. For example, an adhesive having a poor affinity for the surface of the substrate film The treatment may be performed as necessary, for example, when using an adhesive or an adhesive. Corona discharge treatment is preferable to primer treatment from the viewpoint that a chemical such as a solvent is not required.

Regarding the surface wetting tension of the substrate film (the greater the surface wetting tension, the greater the anchoring property of the adhesive or the adhesive), as shown in FIG. The surface wetting tension of the surface of the base film (the smooth surface 4 of the base film 1 in FIG. 1) is 30 Dyn / cm.
It is preferred that: When it is larger than 30 Dyn / cm, it becomes difficult to develop from the adhesive tape wound in a roll shape, and a blocking phenomenon (a phenomenon in which the smooth surface of the adhesive tape and the adhesive stick to an inconvenient degree) occurs. Is not preferred. Further, the surface wetting tension of the non-smooth surface 6 in the case of the adhesive tape as shown in FIG. 1 is preferably 35 Dyn / cm or more.
/ Cm is not preferable because the anchoring property of the pressure-sensitive adhesive to the non-smooth surface 6 is insufficient.

The reinforcing film layer of the pressure-sensitive adhesive tape of the present invention is a layer for suppressing elongation of the pressure-sensitive adhesive tape in the longitudinal direction. The material of the reinforcing film layer is not particularly limited as long as the object of the present invention is not impaired. A preferable material is an unstretched film made of a thermoplastic resin or a film stretched uniaxially or biaxially, and a film stretched uniaxially in the width direction of the adhesive tape is preferable from the viewpoint of the hand-cutting property of the adhesive tape. Specific materials include a polypropylene resin (including a propylene homopolymer, a small proportion of ethylene and a copolymer of the above-mentioned α-olefin, in addition to a propylene homopolymer), and a polyethylene resin (in addition to the ethylene homopolymer, And a copolymer of ethylene and a small proportion of propylene or the above-mentioned α-olefin. Particularly preferred is a high-density polyethylene resin), polyethylene terephthalate resin, and the like. From the viewpoint that a film having a large value is obtained, a polypropylene resin is particularly preferable.

The thickness of the reinforcing film layer is not particularly limited as long as the object of the present invention is not impaired.
0 μm, preferably 10 μm to 50 μm, more preferably 15 μm to 25 μm. It is technically difficult to produce a reinforcing film having a thickness of less than 1 μm,
If it exceeds m, the adhesive tape may hinder hand-cutting.

A method for producing a film for a reinforcing film layer from the above resin is known. For example, it can be produced by a melt extrusion method shown in FIG. 3, and the extruded film is stretched uniaxially or biaxially as required. do it. Also,
A commercially available film may be used as the film for the reinforcing film layer. The film for the reinforcing film layer, especially when using an adhesive or pressure-sensitive adhesive having a poor affinity for the surface of the film, in order to increase the affinity between the surface of the film and the adhesive or pressure-sensitive adhesive, the film Is preferably subjected to corona discharge treatment and / or primer treatment. Corona discharge treatment is preferable to primer treatment from the viewpoint that a chemical such as a solvent is not required.

The pressure-sensitive adhesive relating to the pressure-sensitive adhesive tape of the present invention may be a pressure-sensitive adhesive known in the field of pressure-sensitive adhesive tape, and examples include an acrylic pressure-sensitive adhesive, a vinyl ether-based pressure-sensitive adhesive, a silicon-based pressure-sensitive adhesive, and a rubber-based pressure-sensitive adhesive. I can do it. The form of the pressure-sensitive adhesive is not particularly limited, and may be any type such as a solution-type pressure-sensitive adhesive, an emulsion-type pressure-sensitive adhesive, and a hot-melt-type pressure-sensitive adhesive.
The adhesive relating to the pressure-sensitive adhesive tape of the present invention has an elongation of 70% or less, preferably 40% or less, more preferably 20% or less. When an adhesive having an elongation of more than 70% is used, the adhesive layer becomes easy to elongate, resulting in an unsatisfactory hand-cutting property. The lower the elongation is, the more preferable it is from the viewpoint of the hand-cutting property of the pressure-sensitive adhesive tape. An adhesive having an elongation of 0% (an adhesive having substantially no elongation) is most preferable.

As the adhesive, a rubber-based adhesive such as polyester-based adhesive, chlorinated polypropylene-based adhesive, urethane-based adhesive, nitrile-butadiene rubber (NBR),
Examples thereof include an ethylene-vinyl alcohol (EVA) adhesive, a mixture of these adhesives, and the like, and these adhesives may be commercially available products. Preferred adhesives include polyester-based adhesives and chlorinated polypropylene-based adhesives. The form of the adhesive is not particularly limited, and may be any type such as a solution adhesive, an emulsion adhesive, and a hot melt adhesive.

The elongation percentage of the adhesive is measured by the following method. A 30% by weight solution of the adhesive is applied on silicone paper (release paper) in an amount such that the thickness as a solid content becomes 10 μm, and the applied material is left in a hot-air dryer at 60 ° C. for 2 minutes. Leave at room temperature for 3 days. The adhesive (adhesive film) formed in a film shape is peeled off from the silicone paper, and the elongation of the adhesive film is measured by a tensile tester. The measurement was performed using an adhesive film with a width of 25 mm
The stretching is performed at a speed of 00 mm / min until the adhesive film is broken, and the elongation is determined from the elongation at break. Here, the elongation percentage is a ratio of the length of the elongation to the original length. For example, it is assumed that the elongation percentage when the original length is doubled is 100%.

The structure of the pressure-sensitive adhesive tape of the present invention is not limited to that shown in FIG. 1, but may be a pressure-sensitive adhesive tape having a structure as shown in FIGS. The adhesive tape of FIG. 4 has the same components as the adhesive tape of FIG.
And a pressure-sensitive adhesive layer 3. The pressure-sensitive adhesive tape corresponds to a tape in which the position of the pressure-sensitive adhesive layer 3 in FIG. 1 is changed from the upper side to the lower side in the figure.

The pressure-sensitive adhesive tape of FIG. 5 is a pressure-sensitive adhesive tape in which the positions of the reinforcing film layer 2 and the base film layer 1 of FIG. 1 are interchanged. The pressure-sensitive adhesive tape of FIG. 6 is a pressure-sensitive adhesive tape in which the positions of the base film layer 1 and the reinforcing film layer 2 of FIG. 4 are interchanged. Of these, those of FIGS. 1 and 4 are preferred. 5 and 6, from the viewpoint that the surface of the pressure-sensitive adhesive layer 3 is not non-smoothed by the non-smooth surface of the base material film layer 1 when wound in a roll shape as shown in FIG. If the surface of the agent layer 3 is made non-smooth, the adhesive strength of the adhesive tape may decrease), and the one shown in FIG. 5 is more preferable.

The pressure-sensitive adhesive tape of the present invention is produced by using the above-mentioned base film, reinforcing film, adhesive and pressure-sensitive adhesive as essential components. A method for producing the pressure-sensitive adhesive tape of the present invention is described below. FIG. 7 is a diagram showing a method of manufacturing the pressure-sensitive adhesive tape of FIG. From the roll 21 at the left end of the figure, the base film 1 (a base film having a non-smooth surface subjected to corona discharge treatment or primer treatment, if necessary)
It is supplied continuously with the non-smooth surface facing upward in the figure. After applying the adhesive put in the pan 22 to the non-smooth surface of the base film 1, the applied material is passed through a hot-air dryer 23 in order to remove a solvent or the like contained in the adhesive.
A substrate film with an adhesive that has passed through the hot air dryer 23;
Reinforcing film 2 supplied from roll 24 in the upper part of the figure
(If necessary, a reinforcing film whose surface is subjected to corona discharge treatment or primer treatment) is pressed between rolls 25, and a film obtained by bonding the reinforcing film 2 on the non-smooth surface of the base film 1 is attached to the right end of the figure. Roll 26.
Here, when using an adhesive containing a solvent such as a solution-type adhesive, the type of the solvent and the concentration of the solution may be appropriately determined according to the type of the pressure-sensitive adhesive tape to be produced, and the like. The type of hot air dryer and drying conditions used for the drying may be appropriately determined according to the type of solvent used.

The pressure-sensitive adhesive tape of the present invention can be obtained by applying a pressure-sensitive adhesive to the reinforcing film side of the material wound on the rightmost roll 26 in FIG. 7 by a method known in the field of pressure-sensitive adhesive tapes. Here, when using a pressure-sensitive adhesive containing a solvent such as a solution-type pressure-sensitive adhesive, the type of the solvent and the concentration of the solution may be appropriately determined according to the type of the pressure-sensitive adhesive tape to be produced, and the like. The type of hot air dryer and drying conditions used for the drying may be appropriately determined according to the type of solvent used.

The pressure-sensitive adhesive tape of the present invention comprises an unstretched polyolefin resin base film layer, which is an essential layer described above,
In addition to the reinforcing film layer and the pressure-sensitive adhesive layer, other layers (for example, a further resin film layer) may be included as long as the object of the present invention is not impaired, or each layer (base film layer, The reinforcing film layer, further resin film layer, etc.) may contain various fillers and coloring agents depending on the use of the pressure-sensitive adhesive tape.

As a constitution of the pressure-sensitive adhesive tape having an additional layer and a method for producing the same, for example, the following pressure-sensitive adhesive tapes can be exemplified. A composite film comprising a polypropylene film uniaxially stretched in the width direction and a biaxially stretched polypropylene film is produced by a coextrusion method or a lamination method in which both films are adhered with an adhesive, and the obtained composite film is obtained. For example, the uniaxially stretched film side and the non-smooth surface of the base film are joined with an adhesive, and the adhesive is applied to the biaxially stretched film side of the finally joined one. Since the obtained pressure-sensitive adhesive tape has an additional layer made of a biaxially stretched film, the tensile strength in the longitudinal direction of the pressure-sensitive adhesive tape is increased, and, since the tape is a biaxially stretched film, it is easily torn in the stretching direction in the width direction. Therefore, the hand-cutting property of the adhesive tape is not hindered.

The base film layer and the reinforcing film layer of the pressure-sensitive adhesive tape of the present invention are used to form a flexible pressure-sensitive adhesive tape which can be suitably applied to the surface shape of the adherend to which the pressure-sensitive adhesive tape is to be applied. Alternatively, a porous film having a large number of through holes may be used. The shape of the hole is not particularly limited, but is generally a circle or a similar shape from the viewpoint of ease of production and the like. The diameter of the circle is 0.1mm-5m
m, preferably 0.5 mm to 3 mm, the distance between adjacent circles is 1 mm to 5 mm, preferably 1 mm to 3 m
m. When the diameter of the circle is less than 0.1 mm, the flexibility of the pressure-sensitive adhesive tape is hardly exhibited, and when it exceeds 5 mm, the elongation of the pressure-sensitive adhesive tape in the longitudinal direction is difficult to be suppressed, and the cutting in the width direction of the pressure-sensitive adhesive tape is non-linear. It becomes.

A method for producing a porous film is known.
Needle roll (roll with needles for making holes on the surface)
A method of piercing by passing a film between them may be exemplified. In the case of this method, for example, when a soft film such as a polyethylene film or a too hard film such as polyethylene terephthalate is used, a hole can be formed well by keeping the film in a heated state, and, for example, a stretched polypropylene film. In this case, if the film is not heated, holes can be formed well.

The pressure-sensitive adhesive tape of the present invention is generally manufactured in the form of a roll as shown in FIG. 8 in the same manner as in the case of the conventional pressure-sensitive adhesive tape. 25m, 50m), for example, when a rubber-based adhesive is used as the adhesive or when the amount of the applied adhesive is large, the outer surface of the adhesive tape is required to further improve the spreadability of the adhesive tape. A release agent known for adhesive tapes may be appropriately applied thereon.
Further, a double-sided pressure-sensitive adhesive tape can be obtained by applying a pressure-sensitive adhesive to both sides of a film comprising a base film layer and a reinforcing film layer.

[0032]

EXAMPLES The present invention will be described below in more detail with reference to examples, but the scope of the present invention is not limited by these examples. The physical properties of the pressure-sensitive adhesive tape are measured by the following methods, and the measurement using a tensile tester is performed according to JIS Z1524.
Compliant. Hand-cutting property A pressure-sensitive adhesive tape having an appropriate width (for example, a width of 100 mm; the width is the length in the lateral direction of the adhesive tape, that is, the direction orthogonal to the longitudinal direction) is cut into an appropriate length (for example, a length of 50 mm; length). Is the length of the adhesive tape in the longitudinal direction). As shown in FIG. 9, a single linear cut of 20 mm in length was made in the width direction from one end of the width of the test piece (one end of the right end of the figure) using a cutter knife or the like, and the adhesive layer was placed on the upper side of the figure. And the two edges cut into strips (the upper right edge of the figure and the folded lower left edge)
Is pulled in the opposite direction by a tensile tester at a speed of 300 mm / min. From the obtained data (a graph showing the relationship between the tensile time and the tensile resistance), the initial instantaneous resistance (the initial rise of the tensile resistance on the graph) and the continuous resistance (the subsequent value of the tensile resistance on the graph) ) Was read, and these resistance values were defined as the force required for hand-cutting. The smaller the resistance value, the smaller the force required to cut the hand. It is especially important that the initial instantaneous resistance is small in the hand-cutting property of the adhesive tape. Breaking strength, elongation rate Test piece of adhesive tape (width 25 mm, length 80 mm)
In the length direction at a speed of 300 mm / min by a tensile tester,
The test piece is pulled until it breaks, and the breaking strength and the elongation are determined. The elongation rate is a ratio of the length of the stretched portion to the original length. Flexibility A portion corresponding to a half area (50 mm × 50 mm area) of the test piece of the adhesive tape having a size of 50 mm × 100 mm is stuck to an end of a horizontal upper surface of a desk. In this state,
The portion corresponding to the other half area of the test piece is kept horizontal with the upper surface of the desk in free space outside from the end of the desk.
Place the weight on the part that is kept horizontal in free space and as close as possible from the end of the desk. The maximum weight of the weight when the weight does not yet fall after the weight has been placed on the weight and the minimum weight of the weight when the weight falls immediately after the weight is loaded (Bg). Ask for. Here, A and B are natural numbers. The flexibility of the adhesive tape is represented by a value of (A + 1) g to (B-1) g. The smaller the value, the greater the flexibility of the adhesive tape. Reference Example 1 100 parts by weight of a chlorinated polypropylene-based adhesive (trade name: Hardlen 15LLB) manufactured by Toyo Kasei Kogyo Co., Ltd. and 4-diphenylchloromethane diisocyanate (crosslinking agent; trade name: Coronate manufactured by Nippon Polyurethane Industry Co., Ltd.) 30
15) An adhesive solution (solvent: toluene) having a solid content of 30% by weight containing 15 parts by weight and a kit having a thickness of 15 μm as a solid content (adhesive film) are manufactured by Kite Chemical Industry Co., Ltd.
Was coated on a silicone paper (trade name: 70SN) manufactured by Nissan Co., Ltd., and the coated product was left in a hot-air dryer at 60 ° C. for 2 minutes, and further left at room temperature for 3 days. The adhesive (adhesive film) formed into a film is peeled off from the silicone paper, and the adhesive film having a width of 25 mm is broken at a speed of 300 mm / min using a tensile tester manufactured by Tosoh Seimitsu Kogyo Co., Ltd. The elongation rate of the adhesive film (that is, the elongation rate of the adhesive) was measured by pulling until the tension was reached. The breaking force was 157 g and the elongation was 7%. Reference Example 2 100 parts by weight of a chlorinated polypropylene adhesive (trade name: Hard Len 15LLB) manufactured by Toyo Kasei Kogyo Co., Ltd. and a polyester adhesive (saturated polyester resin; trade name: Byron 50AS) manufactured by Toyobo Co., Ltd. 40 parts by weight of 4-diphenylchloromethane diisocyanate (crosslinking agent, manufactured by Nippon Polyurethane Industry Co., Ltd., trade name: Coronate 30)
15) An adhesive film was prepared in the same manner as in Reference Example 1 from an adhesive solution (solvent: toluene) containing 25 parts by weight and having a solid content of 30% by weight, and its elongation was measured. The breaking force was 240 g and the elongation was 60%. Reference Example 3 100 parts by weight of a chlorinated polypropylene-based adhesive (trade name: Hard Len 15LLB) manufactured by Toyo Kasei Kogyo Co., Ltd. and a polyester-based adhesive (saturated polyester resin; trade name: Byron 50AS) manufactured by Toyobo Co., Ltd. 100 parts by weight of 4-diphenylchloromethane diisocyanate (crosslinking agent, trade name: Coronate 3) manufactured by Nippon Polyurethane Industry Co., Ltd.
015) An adhesive film was prepared in the same manner as in Reference Example 1 from an adhesive solution (solvent: toluene) containing 15 parts by weight and having a solid content of 30% by weight, and its elongation was measured. The breaking force was 297 g and the elongation was 196%. Reference Example 4 100 parts by weight of a polyester adhesive (saturated polyester resin, trade name: Byron 50AS) manufactured by Toyobo Co., Ltd. and 4-diphenylchloromethane diisocyanate (crosslinking agent, manufactured by Nippon Polyurethane Industry Co., Ltd.) An adhesive film was prepared in the same manner as in Reference Example 1 from an adhesive solution (solvent: toluene) containing 15 parts by weight of (Coronate 3015) and a solid content of 30% by weight, and its elongation was measured. The breaking force was 110 g and the elongation was 400% or more. Reference Example 5 One surface is formed as a smooth surface, and the other surface is formed as a non-smooth surface having a concave portion that is a buoy (V) valley-shaped notch parallel line perpendicular to the longitudinal direction (the longitudinal direction when the adhesive tape is formed). Unstretched polyolefin resin base film was prepared by the method described in JP-A-3-47.
It was manufactured as follows based on the method described in Japanese Patent Publication No. 885 (see FIG. 3).

Density 0.970 g / cm ³ , melt index 7.0 g / 10 min (190 ° C., 2.16 kg / cm 3
² ) 25 parts by weight of polyethylene resin, density 0.920 g
/ Cm ³ , melt index 4.0 g / 10 min (190
75 ° C., 2.16 kg / cm ² ), ² parts by weight of a pigment masterbatch composed of 60% by weight of titanium oxide and 40% by weight of the second polyethylene resin, and Irga manufactured by Sumitomo Chemical Co., Ltd. A molten mixture comprising 1 part by weight of a heat stabilizer masterbatch comprising 1% by weight of Knox (trade name), 3% by weight of PEPQ (trade name) manufactured by Sand Japan Co., Ltd. and 96% by weight of the second polyethylene resin was used. At 160 to 190 ° C by an extruder to obtain an extruded film. The extruded film is formed by a rubber roll and a squeezing roll having a smooth surface (a squeezing depth of 0.06 m).
m, an interval of 1 mm), and then cooled and solidified, and then the surface of the non-smooth surface was subjected to a corona discharge treatment at 50 dynes to obtain a base film having a thickness of 0.1 mm. Example 1 The base film and the reinforcing film obtained in Reference Example 5 were joined with an adhesive, and an adhesive tape was produced from the joined film and the adhesive, and evaluated. The reinforcing film is a polypropylene film (trade name: YT22, manufactured by Toray Industries, Inc .; a 25 μm-thick film obtained by co-extruding a biaxially-stretched polypropylene film and a horizontally-stretched polypropylene film). Was used in a direction in which the stretching direction of the polypropylene film was the width direction of the pressure-sensitive adhesive tape, and a pressure-sensitive adhesive tape was produced according to the method of FIG.
As an adhesive, the adhesive solution of Reference Example 1 (solid content 30% by weight)
Of the base film and the biaxially stretched film side of the reinforcing film were bonded with an adhesive. As an adhesive, an acrylic adhesive (trade name: Vinylol PSA AV-6025 manufactured by Showa Polymer Co., Ltd.).
The solvent is a mixed solvent of toluene and ethyl acetate, a mixture comprising 100 parts by weight of a solid content of 45% by weight and 2 parts by weight of an isocyanate crosslinking agent (trade name: Coronate L45) manufactured by Nippon Polyurethane Industry Co., Ltd. Was applied to the reinforcing film side. The pressure-sensitive adhesive tape after applying the pressure-sensitive adhesive and curing at 45 ° C. for 48 hours (the thickness of the pressure-sensitive adhesive layer is 45 μm).
Regarding m), the initial instantaneous resistance was 13 g, the continuous resistance was 17 g, the elongation in the longitudinal direction was 112%, the breaking strength was 7.4 kg, and the flexibility was 13 to 14 g. That is, A = 12, B = 15, and when a weight of 13 g or 14 g was placed, the weight did not immediately fall but fell within 10 minutes. Example 2 The adhesive solution of Reference Example 2 (solid content 30% by weight) was used as the adhesive.
Was prepared in the same manner as in Example 1 except that a toluene solution of (a) was used. The resulting adhesive tape had an initial instantaneous resistance of 17 g, a continuous resistance of 20 g, a longitudinal elongation of 120%, and a breaking strength of 7.5 kg. Comparative Example 1 The adhesive solution of Reference Example 3 (solid content 30% by weight) was used as the adhesive.
Was prepared in the same manner as in Example 1 except that a toluene solution of (a) was used. The initial instantaneous resistance value indicating the hand-cutting property of the obtained adhesive tape was 60 g, and the continuous resistance value was 43 g.
The elongation in the longitudinal direction is 138%, and the breaking strength is 7.5.
kg. Comparative Example 2 The adhesive solution of Reference Example 4 (solid content 30% by weight) was used as the adhesive.
Was prepared in the same manner as in Example 1 except that a toluene solution of (a) was used. The initial instantaneous resistance value of the obtained pressure-sensitive adhesive tape was 90 g or more, and the direction of hand cutting was non-directional and did not cut straight. Example 3 An adhesive tape was obtained in the same manner as in Example 1 except that a porous film was used as a reinforcing film. As the porous film, a film obtained by forming a circular through hole with a needle roll on the reinforcing film of Example 1 was used, and the diameter of the circle was 0.5 mm.
The distance between adjacent circles was 3 mm (vertical and horizontal equidistant). The initial instantaneous resistance value of the obtained adhesive tape was 13
g, the continuous resistance value is 20 g, and the elongation in the longitudinal direction is 12 g.
%, Breaking strength is 4.5 kg, and flexibility is 8 to 9 g (A =
7, B = 10).

[0034]

According to the present invention, an unstretched polyolefin resin base film layer having one surface formed into a smooth surface and the other surface formed into a concave portion having a specific notch parallel line perpendicular to the longitudinal direction of the adhesive tape. , A reinforcing film layer, and an adhesive layer, wherein the film layers have an elongation of 7%.
By being bonded with an adhesive of 0% or less, a pressure-sensitive adhesive tape having good hand-cutting properties and suppressing longitudinal elongation can be obtained.

[Brief description of the drawings]

FIG. 1 is a perspective view of an adhesive tape of the present invention.

FIG. 2 is a perspective view of a base film according to the present invention.

FIG. 3 is a view showing a method for producing a base film according to the present invention.

FIG. 4 is a perspective view of an adhesive tape of the present invention having a structure different from that of the adhesive tape of FIG. 1;

FIG. 5 is a perspective view of another adhesive tape of the present invention having a structure different from that of the adhesive tape of FIG. 1;

FIG. 6 is a perspective view of another adhesive tape of the present invention having a structure different from that of the adhesive tape of FIG. 1;

FIG. 7 is a view illustrating a method for producing an adhesive tape.

FIG. 8 is a perspective view of the pressure-sensitive adhesive tape in a state where the tape is overlapped and wound in a roll shape and a part thereof is drawn out.

FIG. 9 is a perspective view of a test piece of an adhesive piece.

FIG. 10 is a perspective view of a conventional adhesive tape.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Base film layer 2 ... Reinforcement film layer 3 ... Adhesive layer 4 ... Smooth surface 5 ... Depression 6 ... Non-smooth surface 11 ... Melted polyolefin resin 12 ... Extruder 13 ... Rubber roll 14 ... Squeezing roll 15 ... Electrode 16 ... Treatment roll 21 ... Roll 22 ... Pan 23 ... Hot air dryer 24 ... Roll 25 ... Roll 26 ... Roll

Claims (4)

[Claims] 1. A non-aperture having a smooth surface on one side and a notch parallel line on the other surface having a depth perpendicular to the longitudinal direction of the adhesive tape of 0.03 mm to 0.3 mm and an interval of 0.5 mm to 5 mm. An adhesive tape including an unstretched polyolefin resin base film layer formed on a smooth surface, a reinforcing film layer, and an adhesive layer, wherein the film layers are formed of an adhesive having an elongation of 70% or less. Adhesive tape with good hand-cutting properties characterized by being joined. 2. The pressure-sensitive adhesive tape according to claim 1, wherein the pressure-sensitive adhesive tape is bonded with an adhesive having an elongation of 40% or less. 3. The pressure-sensitive adhesive tape according to claim 1, wherein the pressure-sensitive adhesive tape is joined with an adhesive having an elongation of 20% or less. 4. The pressure-sensitive adhesive tape according to claim 1, wherein the base film and / or the reinforcing film is a porous film.