JPH11293205A - Pressure-sensitive adhesive tape and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prepare a pressure-sensitive adhesive tape satisfactory in manual cuttability and flexibility and in productivity as well and to provide a process for producing the same. SOLUTION: This tape consists of a support 1 made of a film made from a thermoplastic resin composition comprising 5-90 wt.%, polypropylene resin, 5-90 wt.% polyethylene resin, and 5-90 wt.% thermoplastic elastomer and made so that one of its surfaces may be smooth, and the other may be non-smooth and may have many groovy recesses in the direction of width of the pressure- sensitive adhesive tape and a pressure-sensitive adhesive layer 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a pressure-sensitive adhesive tape and a method for producing the same. Specifically, the present invention is obtained by applying a pressure-sensitive adhesive to a substrate made of a specific thermoplastic resin composition film having a large number of groove-shaped concave portions in the width direction of the pressure-sensitive adhesive tape, and has a hand-cutting property and flexibility. The present invention relates to a pressure-sensitive adhesive tape which is good and has good productivity of a pressure-sensitive adhesive tape, and a method for producing the same. Here, "hand-cutting property" means the ability to cut the adhesive tape straight in the width direction with only the fingertip of the hand without using a cutting tool such as scissors or a sawtooth-shaped cutter.

[0002]

2. Description of the Related Art Generally, an adhesive tape is, as shown in FIG.
It is composed of a base material 1 made of resin, paper, cloth, metal or the like, and an adhesive layer 2 applied on the base material 1, and is commercially available in the form of a roll wound in a roll shape. The adhesive tape of this form is used by extracting the adhesive tape to a required length from a scroll and cutting it at a desired location. A release agent is applied as necessary on the back surface 3 which is the surface of the base material 1 on which the adhesive is not applied, in order to enhance the ease of pulling out the adhesive tape from the scroll (developability).

[0003] Japanese Patent No. 2,694,854 discloses a pressure-sensitive adhesive tape having good hand-cutting properties obtained by applying a pressure-sensitive adhesive to a substrate made of a thermoplastic resin film having a large number of groove-shaped concave portions in the width direction of the pressure-sensitive adhesive tape. The described adhesive tapes are known. The base material 1 of this adhesive tape is formed of a polyolefin resin film having one surface formed on a smooth surface 4 and the other surface formed on a non-smooth surface 6 having a large number of groove-shaped recesses 5 in the width direction. Material (see FIG. 2),
The good hand-cutting property of the pressure-sensitive adhesive tape (see FIG. 3) formed by applying the pressure-sensitive adhesive 7 on the non-smooth surface 6 is caused by the large number of groove-shaped concave portions 8 formed in the width direction. . The polyolefin resin specifically described in the publication is a polyethylene resin, a polypropylene resin, a copolymer resin of ethylene or propylene and an α-olefin such as butene-1, and the resin described in Examples is polyethylene resin. Resin.

[0004] Regarding the method of manufacturing the base material of the pressure-sensitive adhesive tape, as shown in FIG.
After being extruded into a film by an extruder 11, a squeezing roll 12 having a non-smooth surface (the shape of the squeezing is such that a large number of groove-shaped concave portions are provided in the width direction of the film. By pressing the film between a smooth roll 13 having a substantially smooth surface and a smooth roll 13, the shape of the squeezed pattern is transferred to the surface of the film. Is disposed so as to face the electrode 14, and a substrate is obtained by performing a corona discharge treatment by passing a film between the electrode 14 and the smooth roll 15 having a substantially smooth surface. Is exemplified. The publication describes that corona discharge treatment is performed as necessary.

[0005]

However, the pressure-sensitive adhesive tape described in the above publication has a relatively low melting point when a branched or linear low-density polyethylene resin is used as the polyolefin resin for the base material. Due to the low temperature, it is not possible to raise the temperature of the drying process after applying the pressure-sensitive adhesive to the base material, so the drying process takes time, and as a result, there is a problem in the manufacturing process that the productivity of the adhesive tape is poor. On the other hand, when a high-density polyethylene resin or a polypropylene resin having a high melting point is used, the productivity of the adhesive tape is improved, but the flexibility of the adhesive tape is reduced, and the extruder 11 shown in FIG. Between the squeezing roll 12 and the smoothing roll 13, tension (orientation) is applied to the film in the processing direction (vertical direction in the figure) to increase the tear strength in the width direction of the film, Results have a problem that tends to adversely affect the hand cutting property of the adhesive tape.

An object of the present invention is to provide a pressure-sensitive adhesive tape having good hand-cutting properties and flexibility and good productivity of a pressure-sensitive adhesive tape, and a method for producing the same.

[0007]

Means for Solving the Problems The present inventors have developed an adhesive tape comprising a substrate made of a thermoplastic resin film having a large number of groove-shaped concave portions in the width direction of the adhesive tape, and an adhesive layer. Studies have been made on the development of a pressure-sensitive adhesive tape having good hand-cutting properties and flexibility, and good productivity of the pressure-sensitive adhesive tape. As a result, by using a thermoplastic resin composition comprising a polypropylene-based resin, a polyethylene-based resin, and a thermoplastic elastomer as the resin for the base material, it was found that the object of the present invention could be achieved, The present invention has been completed.

[0008] That is, the present invention relates to a polypropylene-based resin of 5% by weight to 90% by weight and a polyethylene-based resin of 5% by weight.
~ 90% by weight and 5% by weight of thermoplastic elastomer ~ 90
A substrate made of a film made of a thermoplastic resin composition containing 1% by weight, one surface being formed on a smooth surface and the other surface being formed on a non-smooth surface having a number of groove-shaped recesses in the width direction of the adhesive tape. A pressure-sensitive adhesive tape comprising a base material and a pressure-sensitive adhesive layer.

Further, the present invention is a method for producing an adhesive tape comprising the following steps. Step (1): A thin material comprising a film made of a thermoplastic resin composition containing 5% to 90% by weight of a polypropylene resin, 5% to 90% by weight of a polyethylene resin, and 5% to 90% by weight of a thermoplastic elastomer. Is pressed between a squeezing roll and a smoothing roll to form a large number of groove-shaped concave portions in the width direction of the thin object. Step (2): If necessary, the thin object obtained in the step (1) and the hand Step of obtaining a substrate by laminating the film with another film having good cutting properties Step (3): Step of applying an adhesive on at least one surface of the substrate Hereinafter, the present invention will be described in detail. When illustrated by figures, 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.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The polypropylene resin for the base material of the pressure-sensitive adhesive tape of the present invention is a thermoplastic resin mainly composed of a polymer chain derived from propylene, and may be a known resin. As the resin, propylene homopolymer resin (homopolypropylene resin); propylene such as a copolymer resin of propylene and ethylene, a copolymer resin of propylene and butene, and a copolymer resin of propylene, ethylene and butene; A copolymer resin with one or two or more α-olefins; a mixture of these resins may be exemplified, and the copolymer resin may be a random copolymer resin or a block copolymer resin. It doesn't matter. From the viewpoint of improving the productivity of the pressure-sensitive adhesive tape, which is the object of the present invention, a homopolypropylene resin having excellent heat resistance (high melting point) is preferred. The physical properties of the polypropylene-based resin are not particularly limited, and may be appropriately set according to the use of the pressure-sensitive adhesive tape. From the viewpoint of hand-cutting properties, the melt flow rate (hereinafter, also referred to as MFR) is about 30 g / 10 min. Larger ones are preferred.

The polyethylene resin used as the base material of the pressure-sensitive adhesive tape of the present invention is a thermoplastic resin mainly composed of a polymer chain derived from ethylene, and may be a known resin. As the resin, a homopolymer resin of ethylene (homopolyethylene resin); a copolymer resin of ethylene and propylene, a copolymer resin of ethylene and butene, and a copolymer resin of ethylene, propylene and butene; Copolymer resins with one or more α-olefins;
A mixture of these resins can be exemplified, and the copolymer resin may be a random copolymer resin or a block copolymer resin. From the viewpoint of film formation stability when forming a film, a resin having a high melt tension, such as a branched low-density polyethylene resin produced by a high-pressure polymerization method, is preferable. MFR of polyethylene resin
The physical properties such as density are not particularly limited, and may be appropriately set according to the moldability, the use of the adhesive tape, and the like.

The thermoplastic elastomer according to the substrate of the pressure-sensitive adhesive tape of the present invention is different from ordinary rubber in spite of having physical properties similar to rubber (for example, flexibility and resilience). It is a high molecular substance that can be processed similarly to a thermoplastic resin. The thermoplastic elastomer according to the present invention may be a known thermoplastic elastomer, and may be a copolymer of ethylene and propylene (EPR), a copolymer of ethylene and butene (EBR), or an ultra low density polyethylene (ULDPE). Olefinic thermoplastic elastomers, such as copolymers of propylene and α-olefins (butene, etc.); styrenes, such as copolymers of the type in which a styrene polymer is bonded to one or both ends of the molecular chain of the olefin polymer −
Olefin-based thermoplastic elastomers; styrene-butadiene-based thermoplastic elastomers such as block copolymers of styrene and butadiene (SB, SBS) and hydrogenated products thereof (SEB, SEBS); block copolymers of styrene and isoprene ( SI, SIS) and its hydrogenated products (S
Examples thereof include styrene-isoprene-based thermoplastic elastomers such as EP and SEPS.

The preferred thermoplastic elastomer for the base material of the pressure-sensitive adhesive tape of the present invention is preferably made of EP from the viewpoint of improving the flexibility and strength of the film and the dispersibility in the composition.
An olefin-based thermoplastic elastomer, which is a copolymer of ethylene and α-olefin such as R or EBR, having a density of 0.910 g / cc or less and a density of 0.900 g from the viewpoint of flexibility. / Cc or less is preferred. Although the MFR of the thermoplastic elastomer is not particularly limited, from the viewpoint of dispersibility in the composition, the MFR and the MFR of the polypropylene-based resin or polyethylene-based resin constituting the composition are not limited.
It is preferable that the FR is not greatly different from the FR.

The components constituting the thermoplastic resin composition according to the base material of the pressure-sensitive adhesive tape of the present invention are 5 to 90% by weight of a polypropylene resin, 5 to 90% by weight of a polyethylene resin, The content of the thermoplastic elastomer is 5% by weight to 90% by weight, and from the viewpoint of obtaining a film having excellent heat resistance, the proportion of the polypropylene-based resin 50 is such that the polypropylene-based resin can form the continuous phase of the composition.
% By weight or more is preferred. From the viewpoint of improving the flexibility and strength of the film, the amount of the thermoplastic elastomer may be increased, and from the viewpoint of improving the film forming stability, the amount of the polyethylene resin may be increased.

The physical properties of the preferable base material for the pressure-sensitive adhesive tape of the present invention, that is, the base material having more excellent heat resistance, flexibility and mechanical strength, are as follows. Temperature is 120 ° C. or higher;
(B) The load at the time of the dimensional change of 1% is MD direction and T
1.0 kg / 20 mm width or less in both D directions;
(C) The elongation in the tensile test is 50% or more in both the MD and TD directions. The base material satisfying the above (a) has more excellent heat resistance, and the above (b)
The base material satisfying (c) has more excellent flexibility, and the base material satisfying (c) has more excellent mechanical strength (elongation and not brittleness).

The base material for the pressure-sensitive adhesive tape of the present invention is MD
The elongation in the direction is preferably 700% or less. In the case of a substrate having an elongation of more than 700%, when the adhesive tape is cut by hand, the substrate expands at the starting point of cutting, and a necking phenomenon occurs in that portion, thereby increasing the tear strength of the substrate. As a result, the hand-cutting property may not be good.

A typical example of the base material according to the pressure-sensitive adhesive tape of the present invention is a single-layer material similar to the base material 1 shown in FIG. 2 except that the material of the base material is different from that described in the above publication. Of the base material. The substrate shown in this figure is a substrate in which one surface is formed as a smooth surface and the other surface is formed as a non-smooth surface having a number of groove-shaped concave portions in the width direction of the adhesive tape. Regarding the application of the pressure-sensitive adhesive to the substrate, it is preferable to apply the pressure-sensitive adhesive to the non-smooth surface 4 of the substrate 1 as shown in FIG. It may be applied to the smooth surface 4 of the material 1.

The reason why it is preferable to apply an adhesive to the non-smooth surface 4 of the base material 1 as shown in FIG. 3 is that when the roll shown in FIG. Because it is not inhibited, the adhesive strength does not decrease,
Further, when corona discharge treatment is performed on the non-smooth surface (see FIG. 4), since the smooth surface of the base material is not subjected to corona discharge treatment (because strike-through of corona discharge treatment does not occur), the development property does not decrease. It is.

The shape of the concave portion on the non-smooth surface of the base material according to the pressure-sensitive adhesive tape of the present invention may be, for example, a buoy (V) valley shape formed continuously from one end to the other end of the base material without any break. Shape (see FIG. 2). The shape of the concave portion shown in FIG. 2 is a preferable shape from the viewpoint of the hand-cutting property and the good appearance of the cut portion when cut by hand. The shape is not limited to the shape, and may be another shape such as a U-shaped trough, or may be a discontinuous concavely formed concave portion.

Regarding the size of the concave portion (see FIG. 2) on the base material of the pressure-sensitive adhesive tape of the present invention, the depth D is 0.03 mm or more.
0.3 mm, preferably 0.04 mm to 0.12 mm, if less than 0.03 mm, the hand-cutting property is unsatisfactory,
If it is larger than 0.3 mm, the hand-cutting property is good, but the tensile strength in the longitudinal direction is small, and if the depth is extremely large, the inconvenience that the adhesive tape is cut at an unexpected place when the adhesive tape is developed from the roll occurs. Sometimes. The distance W between adjacent concave portions is 0.5 mm to 5 mm, preferably 0.6 mm to 5 from the viewpoint of obtaining an adhesive tape having good hand-cutting properties.
1.4 mm. The thickness T may be appropriately determined depending on the use of the pressure-sensitive adhesive tape, and is generally 0.04 mm to 0.4 mm.
mm. The difference between the thickness T and the depth D (T
-D) is generally 0.01 mm to 0.1 mm from the viewpoint of obtaining an adhesive tape having good hand-cutting properties.

The method of forming the concave portion on the base material of the pressure-sensitive adhesive tape of the present invention is not limited. However, the method described in the above-mentioned publication (see FIG. 4), that is, the method of forming a thin film made of a film made of a thermoplastic resin composition, Pressing between a smoothing roll and a squeezing roll for forming a number of groove-shaped recesses (the shape of the squeezing is a shape providing a number of groove-shaped recesses in the width direction of the film); A method of forming a large number of groove-shaped concave portions in the width direction of a thin object is a simple method which is preferable and is a general method.

When the concave portion is formed by the method shown in FIG. 4, the film which has been softened immediately after being extruded from the extruder may be pressed as it is between the squeezing roll and the smoothing roll, or may be produced in advance. After the film at room temperature (the film in the solidified state) is heated and softened, the film may be pressed between the squeezing roll and the smoothing roll. When a film having a concave portion is manufactured by the method shown in FIG. 4, unless the shape of the concave portion is deformed to an inconvenient degree or the like, for the purpose of enhancing the physical properties of the film, for example, a squeezing roll is used. The film may be stretched after pressing with a roll.

Here, "smooth" used in the present specification is used.
The term “substantially smooth” is a term commonly used in the field of resin films and the like. That is, it does not mean smoothness in a strict sense without any physical unevenness, but is a term used for non-smoothness when a concave portion or the like is positively formed in a film using a squeezing roll or the like. .
Therefore, it is assumed that some unevenness (a slight unevenness comparable to that of the non-smooth surface) occurs on the surface having a history of contact with the smooth roll due to stretching after pressing by the squeezing roll and the smooth roll. However, a surface having such irregularities is not a non-smooth surface but a smooth surface.

The pressure-sensitive adhesive for the pressure-sensitive adhesive tape of the present invention is not particularly limited, and may be a pressure-sensitive adhesive known in the field of pressure-sensitive adhesive tapes. Examples of the adhesive include an acrylic adhesive, a vinyl ether-based adhesive, a silicone-based adhesive, and a rubber-based adhesive. 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 method of applying the pressure-sensitive adhesive is not particularly limited, and a method known in the field of pressure-sensitive adhesive tapes such as a roll coater method may be employed. The thickness of the pressure-sensitive adhesive layer is also not particularly limited, and the size of the pressure-sensitive adhesive tape (width and thickness of the base material)
And may be determined appropriately according to the application and the like.
50 μm.

The pressure-sensitive adhesive tape of the present invention means not only a pressure-sensitive adhesive tape having only one surface of a substrate coated with a pressure-sensitive adhesive, but also a double-sided pressure-sensitive adhesive tape having both surfaces of a substrate coated with a pressure-sensitive adhesive, In addition, a removable tape is also meant. When a re-peelable pressure-sensitive adhesive tape is used, the pressure-sensitive adhesive may be appropriately selected from pressure-sensitive adhesives known in the field of re-peelable tapes.

The base material of the pressure-sensitive adhesive tape of the present invention is not limited to the single-layer film shown in FIG. 2, and as long as the object of the present invention is not impaired, the base material shown in FIG. It may be a multi-layer film composed of a single-layer film and another film made of resin, paper, cloth, metal, or the like and having good hand-cutting properties. FIG. 5 shows an example of the pressure-sensitive adhesive tape of the present invention using a multilayer substrate. The base material 21 of the pressure-sensitive adhesive tape shown in FIG.
2 (a film on the upper side of the substrate) and a film 23 (a film on the lower side of the substrate) having good hand-cutting properties. For example, when a stretched film is used as the film 23 on the lower side of the base material, the stretched film made of a polyolefin resin such as a uniaxially stretched polypropylene resin film and the film 22 on the upper side of the base material are cut into pieces of adhesive tape. The base material can be manufactured by a method in which the stretched film is positioned so that the stretching direction of the stretched film and the width direction of the pressure-sensitive adhesive tape coincide with each other so that the properties are not impaired, and both films are laminated with an adhesive. As another manufacturing method of the base material shown in FIG. 5, after a resin composition for forming the upper film 22 is extruded and laminated on the lower film 23, the concave portion 24 is formed in the upper film 22. The method of forming may also be exemplified. The adhesive tape shown in FIG. 5 has the adhesive 25 applied to the upper film 22, but the adhesive 25 may be applied to both surfaces of the lower film 23 or the base 21.

FIG. 6 shows another embodiment of the pressure-sensitive adhesive tape of the present invention using a multilayer substrate. The base material of the adhesive tape shown in this figure is a film 3 having a concave portion 31 as shown in FIG.
2 is formed by laminating a non-smooth surface and a film 34 having good hand-cutting properties with an adhesive 35, and an adhesive 36 is applied to the smooth surface 36 of the former film 32. As a method for producing the substrate, a method in which both films are separately produced, the non-smooth surface is located inside the substrate, and the substrate is obtained by laminating with an adhesive can be exemplified. Although not shown, the adhesive may be applied to the film on the upper side of the figure or may be applied to both surfaces of the substrate.

The thickness of a film having good hand-cutting properties exemplified in FIGS. 5 and 6 is generally 1 μm to 100 μm, preferably 10 μm to 50 μm, more preferably 15 μm to 25 μm.
m. It is technically difficult to produce a film having a thickness of less than 1 μm, and a film having a thickness of more than 100 μm may hinder the adhesive tape from being cut. The surface of the film according to the substrate of the pressure-sensitive adhesive tape of the present invention, in order to increase the affinity between the film and the adhesive, and when using a substrate composed of a multilayer film, the affinity between the film and the adhesive If necessary, a corona discharge treatment (see FIG. 4) or a primer treatment may be performed.

When a substrate composed of a multilayer film is used, the adhesive used for bonding the films is polyester-based adhesive, chlorinated polypropylene-based adhesive,
Urethane adhesive, nitrile-butadiene rubber (NB
R) and the like, rubber-based adhesives such as R), ethylene-vinyl alcohol (EVA) -based adhesives, mixtures of these adhesives, and the like, and these adhesives may be publicly known. 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.

When a multi-layered base material is used as the base material of the pressure-sensitive adhesive tape of the present invention, the number of layers is not limited to two as shown in FIGS. 5 and 6, but may be three or more. Also, each layer and pressure-sensitive adhesive may contain a coloring agent such as a pigment, an antioxidant, a dispersant, a filler, an antistatic agent, and the like.

[0031]

EXAMPLES The present invention will be described in more detail with reference to the following examples, but the scope of the present invention is not limited by these examples. The measuring methods of the physical properties shown in Examples and Comparative Examples are as follows. Elongation at break Test speed 500 mm according to JIS K-7113
Per minute in an atmosphere of 23 ° C. 1% tensile load Measured in an atmosphere at 23 ° C. in accordance with JIS K-7113. The stress at the time of 1% deformation was determined for the stress-deformation curve at the start of elongation. Using thermal mechanical analysis Seiko Instruments of TMA220, cut parallel to the tape processing direction strips of 3 mm × 20 mm as a test piece, the temperature rise rate of 1 as a chuck distance 10mm
A constant load measurement was performed at 0 ° C./min and 1%, that is, 0.
The lowest temperature at which the elongation of 1 mm was observed was used as an index of heat resistance. When a film- forming processable resin composition is introduced into an extruder to form a film described on a tape, no fluctuation in the amount of extrusion or poor take-off molding occurs, and good film forming is performed at a take-up speed of approximately 20 m / min. Was determined as a criterion.

◎: extremely good 良好: good ×: poor (fluctuations in thickness are apparent in the film) Example 1 As a polypropylene resin, Noblen X101A manufactured by Sumitomo Chemical Co., Ltd. (density 0.890 g / cm ³ , MF)
R50 g / 10 min), 60 wt%, Sumikasen G701 (density 0.919 g / cm ³ , MFR 6.8 g / 10 min) manufactured by Sumitomo Chemical Co., Ltd. as a polyethylene resin, 20 wt%, and Dow Chemical as a thermoplastic elastomer. Engage EG8200 (density 0.870 g / cm ³ , MFR 5.0 g / 10 min) manufactured by Japan Co., Ltd.
Pellets were mixed at 0% by weight and extruded at 185 ° C. to obtain a molten sheet. A rubber roll capable of forming one surface of the molten sheet as a smooth surface and a squeezing roll having a surface capable of forming the other surface as an uneven surface are 20 m / m.
The material was pressed while being taken up at a speed of one minute, cooled and solidified, and the drawn pattern was transferred. At this time, the temperature of the hot water circulating in the roll was adjusted so that the surface temperatures of the rubber roll and the squeezing roll were about 60 ° C. Further, a base film for an adhesive tape was obtained by subjecting the surface of the uneven surface of the film to a corona discharge treatment so as to have 45 dynes.

A copolymer comprising butyl acrylate (80% by weight) and 2-ethylhexyl acrylate (20% by weight) as an acrylic pressure-sensitive adhesive on the uneven surface of a drawn 100 μm thick resin composition film. Of a 40% by weight mixed solution of ethyl acetate and toluene (viscosity of about 4000
cps) with a roll coater, passed through a drying furnace set at 120 ° C. at a speed of 30 m / min, and dried to form a 30 μm-thick acrylic pressure-sensitive adhesive layer on the resin composition film. Obtained.

The physical properties of the resulting pressure-sensitive adhesive tape and other properties are shown in Table 1. As shown in the table, it is understood that the hand-cutting property and flexibility required for the pressure-sensitive adhesive tape are good, and the film-forming workability at the time of forming the base film is also good. Also, as can be seen from the heat resistant temperature, even if the drying temperature at the time of performing the adhesive application processing is set to a relatively high temperature of 120 ° C., since the film does not deform, it is possible to dry at this temperature, As a result, there is an economic advantage that the drying speed can be increased. Examples 2.3 As a thermoplastic elastomer, in Example 2, Dynalon 1320P (MFR3.
5 g / 10 min) in Example 3 and Tuffmer A4085 (MFR 4.0 g / 10 min.
Ex.) Was obtained in the same manner as in Example 1 except that the adhesive tape was used. In both examples, the temperature at the time of applying the pressure-sensitive adhesive could be set to 120 ° C. from the viewpoint of heat resistance, and as a result, the drying temperature could be set to an economic speed of 30 m / min.

Table 1 shows the physical properties and the like of the obtained pressure-sensitive adhesive tape. In each case, almost the same tape properties as those of Example 1 were obtained, and there was no problem in the film forming processability of the base film. Examples 4 and 5 The three types of thermoplastic resins used are the same as in Example 1, but the mixing ratio is 80% by weight in Example 4.
/ 10% by weight / 10% by weight, and in the case of Example 5, it was 50% by weight / 25% by weight / 25% by weight. Otherwise, an adhesive tape was obtained in exactly the same manner as in Example 1. In the case of Example 4, as in Example 1, as the drying conditions, a temperature of 120 ° C. and a speed of 30 m / min were possible, but in Example 5, when the temperature was set to 120 ° C., the film was slightly deformed. Since it was seen, it was performed at 110 ° C., and the speed was 25 m / min.

Table 1 shows the physical properties and the like of the obtained adhesive tape.
Show. In any case, excellent suitability as adhesive tape
In addition, the film formability of the base film is also good.
Was. Comparative Example 1 High-density polyethylene (Nippon Polychem) as a thermoplastic resin
Novatec HD HJ381 (Density 0.96)
0 g / cm^Three, MFR 10 g / 10 min)) 35% by weight
And low-density polyethylene (Nova made by Nippon Polychem Co., Ltd.)
Tech LD LC720 (density 0.915g / cm^Three,
MFR 10 g / 10 min)) using a mixture with 65% by weight
Except that the adhesive tape was obtained in exactly the same manner as in Example 1.
Was. However, in this case, drying at 120 ° C.
It is impossible to perform the adhesive application processing under the conditions,
° C.
Must be dried at a low speed of m / min.
Was something.

Table 1 shows the physical properties and the like of the obtained pressure-sensitive adhesive tape. The tape is inferior in heat resistance, and the drying temperature at the time of applying the pressure-sensitive adhesive must be lowered. Comparative Example 2 The same polypropylene-based resin and polyethylene-based resin as in Example 1 were used, but the thermoplastic elastomer was not mixed, and the mixing ratio of the polypropylene-based resin and the polyethylene-based resin was 80% by weight / 20% by weight. A pressure-sensitive adhesive tape was obtained in exactly the same manner as in Example 1 except that this was performed. The same drying conditions as in Example 1 were possible for drying the tape during the application of the adhesive.

Table 1 shows the physical properties and the like of the obtained pressure-sensitive adhesive tape. This tape had a very low tensile elongation of TD, and was apt to be longitudinally torn by MD when used as a tape, making it practically difficult to use. In addition, the value of 1% deformation load is large and it is a tape with poor flexibility,
Also in this respect, the tape was inferior in suitability. Comparative Example 3 The same polypropylene-based resin and thermoplastic elastomer as in Example 1 were used, but the polyethylene-based resin was not mixed, and the mixing ratio between the polypropylene-based resin and the thermoplastic elastomer was 60% by weight / 40% by weight. A pressure-sensitive adhesive tape was obtained in exactly the same manner as in Example 1 except that this was performed. However, when the base film of the tape was extruded, a molding defect phenomenon called so-called take-over surging occurred, and a remarkable variation in thickness was observed in the film. There was no one. Comparative Example 4 Extrusion molding of a base film was performed in exactly the same manner as in Example 1 except that the temperature of the hot water circulating in the roll was adjusted so that the surface temperatures of the rubber roll and the squeezing roll were about 15 ° C. To obtain an adhesive tape.

Table 1 shows the physical properties and the like of the obtained pressure-sensitive adhesive tape. Since the tape had a very large MD elongation, the film was easily deformed when cut by hand, resulting in poor hand-cutting properties.

[0040]

[Table 1]

[0041]

According to the present invention, one surface becomes a smooth surface,
In a pressure-sensitive adhesive tape composed of a non-smooth surface having a large number of groove-shaped recesses in the width direction on the other surface and a pressure-sensitive adhesive layer, the base material is made of 10% by weight of a polypropylene resin.
By using a substrate made of a thermoplastic resin composition film containing 80% by weight, 10% by weight to 80% by weight of a polyethylene resin and 10% by weight to 80% by weight of a thermoplastic elastomer, hand-cutting properties and flexibility are improved. A good adhesive tape can be obtained with high productivity.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an adhesive tape in the form of a roll wound in a roll shape.

FIG. 2 is a perspective view showing a resin base material in which one surface is formed as a smooth surface and the other surface is formed as a non-smooth surface having a number of groove-shaped recesses in the width direction.

FIG. 3 is a perspective view showing an adhesive tape including a base material and an adhesive layer shown in FIG. 2;

FIG. 4 is a cross-sectional view showing a method of manufacturing the base material shown in FIG.

FIG. 5 is a perspective view showing an adhesive tape of the present invention using a multilayer base material.

FIG. 6 is a perspective view showing another pressure-sensitive adhesive tape of the present invention using a multilayer substrate.

[Explanation of Signs] 1 ... Substrate 2 ... Adhesive layer 3 ... Back surface 4 ... Smooth surface 5 ... Concave 6 ... Non-smooth surface 8 ... Concave 10 ... Molten resin 11 ... Extruder 12 ... Squeezing roll 13 ... Smooth roll DESCRIPTION OF SYMBOLS 14 ... Electrode 15 ... Smooth roll 21 ... Substrate 22 ... Film with a concave part 23 ... Film with good hand-cutting property 24 ... Concave part 25 ... Adhesive 30 ... Substrate 31 ... Concave part 32 ... Film with a concave part 33 ... Non-smooth Surface 34: Film with good hand cutting properties 35: Adhesive 36: Smooth surface

Claims (20)

[Claims] 1. A base comprising a film made of a thermoplastic resin composition containing 5% to 90% by weight of a polypropylene resin, 5% to 90% by weight of a polyethylene resin and 5% to 90% by weight of a thermoplastic elastomer. A pressure-sensitive adhesive tape, comprising: a base material having one surface formed on a smooth surface and the other surface formed on a non-smooth surface having a large number of groove-shaped recesses in the width direction of the pressure-sensitive adhesive tape; and a pressure-sensitive adhesive layer. 2. The pressure-sensitive adhesive tape according to claim 1, wherein the polypropylene resin is a homopolypropylene resin. 3. The adhesive tape according to claim 1, wherein the polypropylene resin is a homopolypropylene resin having a melt flow rate of 30 g / 10 minutes or more. 4. The content ratio of the polypropylene resin is 50.
The pressure-sensitive adhesive tape according to claim 1, wherein the amount is from 80% by weight to 80% by weight. 5. The pressure-sensitive adhesive tape according to claim 1, wherein the polyethylene resin is a branched low-density polyethylene resin produced by a high-pressure polymerization method. 6. The thermoplastic elastomer has a density of 0.910.
2. The pressure-sensitive adhesive tape according to claim 1, wherein the pressure-sensitive adhesive tape is a copolymer of g / cc or less of ethylene and an α-olefin. 7. The pressure-sensitive adhesive tape according to claim 1, wherein the base material satisfies the following (a) to (c). (A) The temperature at which a dimensional change of 1% or more in thermomechanical measurement is observed is 120 ° C. or more. (B) The load at the time of the dimensional change of 1% is MD direction and T
1.0 kg / 20 mm width or less in both D directions (c) Elongation in tensile test is 50% or more in both MD and TD directions 8. The pressure-sensitive adhesive tape according to claim 1, wherein the base material has an elongation in the MD direction of 700% or less. 9. The pressure-sensitive adhesive tape according to claim 1, wherein the base material is a single layer made of a film made of a thermoplastic resin composition. 10. The depth of the recess is 0.03 mm to 0.3 m.
m, the interval between concave portions is 0.5 mm to 5 mm, and the thickness of the base material is 4
2. The pressure-sensitive adhesive tape according to claim 1, wherein the thickness is from 0 μm to 400 μm, and the difference between the thickness of the base material and the depth of the concave portion is from 0.01 mm to 0.1 mm. 11. A method for producing a pressure-sensitive adhesive tape, comprising the following steps. Step (1): A thin material comprising a film made of a thermoplastic resin composition containing 5% to 90% by weight of a polypropylene resin, 5% to 90% by weight of a polyethylene resin, and 5% to 90% by weight of a thermoplastic elastomer. Is pressed between a squeezing roll and a smoothing roll to form a large number of groove-shaped concave portions in the width direction of the thin object. Step (2): If necessary, the thin object obtained in the step (1) and the hand Step of laminating with another film having good cutting properties to obtain a substrate Step (3): applying an adhesive to at least one surface of the substrate 12. The method according to claim 11, wherein the polypropylene resin is a homopolypropylene resin. 13. The method according to claim 11, wherein the polypropylene resin is a homopolypropylene resin having a melt flow rate of 30 g / 10 minutes or more. 14. The content ratio of the polypropylene resin is 5
The method for producing a pressure-sensitive adhesive tape according to claim 11, wherein the content is 0% to 80% by weight. 15. The method for producing an adhesive tape according to claim 11, wherein the polyethylene resin is a branched low-density polyethylene resin produced by a high-pressure polymerization method. 16. The thermoplastic elastomer has a density of 0.91.
The method for producing a pressure-sensitive adhesive tape according to claim 11, which is a copolymer of ethylene and an α-olefin of 0 g / cc or less. 17. The method for producing a pressure-sensitive adhesive tape according to claim 11, wherein the base material satisfies the following (a) to (c). (A) The temperature at which a dimensional change of 1% or more in thermomechanical measurement is observed is 120 ° C. or more. (B) The load at the time of the dimensional change of 1% is MD direction and T
1.0 kg / 20 mm width or less in both D directions (c) Elongation in tensile test is 50% or more in both MD and TD directions 18. The method for producing a pressure-sensitive adhesive tape according to claim 11, wherein the substrate is a substrate having an elongation in the MD direction of 700% or less. 19. The method for producing a pressure-sensitive adhesive tape according to claim 11, wherein the substrate is a single layer of a film made of a thermoplastic resin composition. 20. The recess has a depth of 0.03 mm to 0.3 m.
m, the interval between concave portions is 0.5 mm to 5 mm, and the thickness of the base material is 4
The method for producing a pressure-sensitive adhesive tape according to claim 11, wherein the difference between the thickness of the base material and the depth of the recess is 0.01 mm to 0.1 mm.