JP2588843B2 - Adhesive tape - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in an adhesive tape, and is preferably used as a material for packaging and a material for curing. It was done.

[0002]

2. Description of the Related Art A pressure-sensitive adhesive tape adheres with a light pressure of a fingertip or the like without the aid of a solvent or heat, and basically comprises a tape base material and a pressure-sensitive adhesive layer. The pressure-sensitive adhesive is selected from acrylic, rubber, silicone, etc. depending on the application and function.For the tape base, besides the conventional kraft paper and film, the pressure-sensitive adhesive can be used in the horizontal direction of the adhesive tape. In order to obtain an easy-to-use adhesive tape that can be easily cut in a straight line by hand without using scissors or cutters, those using woven fabrics have come to be seen.

As the woven fabric, various types of adhesive tapes using a flat yarn cloth as a tape base material as shown in FIG. 2 have been disclosed. Specifically, coarsely woven flat yarns have been disclosed. A plastic film layer is formed on one surface of the cloth and an adhesive layer is formed on the other surface.
No.) or a flat yarn cloth with a plastic film layer on both sides and an adhesive layer on one side (J.
Nos. 51-28352 and 54-4547).

In order to improve the hand-cutting property of the adhesive tape in the weft direction, the warp yarns each form a first laminating layer on one side of a cross of a flat yarn of a specific fineness and further form a surface thereof. A second laminating layer is formed on the other side and an adhesive layer is provided on the other side (Japanese Patent Publication No. 1-19718), and laminating is performed on the cross surface and the back side of a flat yarn of specific fineness, respectively. And an adhesive layer was formed so that the adhesive layers were bonded (Japanese Patent Publication No. 41189/1989).

[0005] These adhesive tapes are formed with a laminating layer in order to fix the structure of the base fabric. However, since the crossing portions of the warp yarns cannot be fixed sufficiently, unevenness in hand-cutting properties occurs. The cut surface tended to be fluffy.

Therefore, an adhesive tape is used as a base material by heat-sealing the intersection of warp yarns with a cross sheet woven using a composite yarn as the warp yarn (Japanese Patent Laid-Open No. 1-115981, Japanese Utility Model Application Laid-Open No. -106538)
However, since it is basically a woven cloth, since the warp which is the cut portion is located alternately on the front and back sides with respect to the weft, the difference in the fusion property and the degree of thermal deterioration between the front and back sides Therefore, even if the warp located on one side is cut cleanly, the warp located on the other side may be fluffed and cannot be completely suppressed.

[0007]

SUMMARY OF THE INVENTION Therefore, the present invention suppresses partial unevenness in order to obtain good hand-cutting properties without causing misalignment between the warp and the weft of the nonwoven fabric in which the yarn groups are overlapped. It is an object of the present invention to provide an adhesive tape having a beautiful cut surface.

[0008]

SUMMARY OF THE INVENTION The present invention relates to a fabric and a laminate coating layer 3 laminated on one or both sides of the fabric.
In the pressure-sensitive adhesive tape 1 having a tape base material formed thereon and a pressure-sensitive adhesive layer 4 provided on at least one surface of the laminating coating layer, the cloth has two or more kinds having different melting points. A large number of composite yarns composed of a synthetic resin and having a high melting point component as the core portion 7 and a low melting point component as the outer skin portion 8 are arranged in such a manner that two yarn groups arranged substantially in parallel are arranged so as to be orthogonal to each other. It is a nonwoven fabric 2 which is heat-fused in a temperature range of not less than the melting point of the outer resin of the composite yarn and not more than the melting point of the resin of the core, together with a weft yarn, and the intersection is fused and integrated. It is a characteristic adhesive tape.

According to the non-woven fabric 2 having the structure shown in FIGS. 3 and 4, the arranged composite yarns are softened and melted by the outer cover 8 made of a synthetic resin having a lower melting point than the synthetic resin of the core 7, The outer skin portions of the superposed yarns that are in contact with each other are securely and firmly fused and integrated, so that the warp 5 and the weft 6 do not misalign without being easily separated. As a result, the intersections between the warp yarns 5 and the weft yarns 6 are fixed and the load when cutting in the weft direction by hand is reliably applied to the warp yarns 5, and the hand-cutting property in the same direction can be improved.

A composite yarn composed of a core 7 of a high melting point component and a skin 8 of a low melting point component used for the warp of the nonwoven fabric 2 is formed by a multi-layer T-die flat method or an inflation method. Extruded laminated or sequentially extruded lamination
Composite flat yarn obtained by shredding a three-layer film composed of a core layer and both outer layers laminated by the
And a composite monofilament obtained by being extruded in a molten state from a multi-layer nozzle in a core-sheath structure, and then cooled and then uniaxially stretched. As a tape base material, a flat yarn which is a flat yarn having excellent surface smoothness is used. -Is most preferred.

As the synthetic resin constituting each layer of the composite yarn, a thermoplastic synthetic resin corresponds to stable quality and continuous productivity. As the thermoplastic synthetic resin of the high melting point component to be the core 7, for example, polypropylene, high Representative examples include high-density polyethylene, polyester, polyamide, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, polystyrene, polyacrylonitrile, and copolymers belonging to these series.
As a thermoplastic synthetic resin of a low melting point component, for example,
Examples include low-density polyethylene, polyethylene-polypropylene random copolymer, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, and the like.

[0012] The fineness of the composite yarn used for the warp 5 is not particularly limited, but is preferably 50 to 250dr, more preferably 80 to 150dr. This is because if it is less than 50dr, the tensile strength is weak and it is easy to break due to the impact during use as a packaging material, and if it exceeds 250dr, the tear strength is large and it is difficult for the hand-cutting property to be good. .

The fineness of the composite yarn used for the weft 6 is preferably about 3 times higher than that of the warp. This is preferable in that it has a sufficient strength to prevent oblique cracks so that it can be cut straight along the weft arranged in the width direction of the adhesive tape, and furthermore, it has a good appearance as a tape base material. Because.

The arrangement number of the warp yarns 5 and the weft yarns 6 is not particularly limited, but is preferably about 10 to 45 yarns / inch, and the distance between the warp yarns is about 0.3 to 2.5 mm, and the weft is 0.1 to 1.0 mm. By setting the degree to such a value, it has appropriate tensile strength in the warp direction and tear strength in the weft direction, and exhibits a good appearance and a beautiful cut surface.

The non-woven fabric 2 used as the base material of the adhesive tape 1 of the present invention comprises, among the composite yarns described above, a group of warp yarns in which a large number of warp yarns 5 are arranged substantially in parallel at a predetermined density. And a group of weft yarns in which a large number of weft yarns 6 are arranged substantially in parallel at a predetermined density.

Means for arranging the yarns include, for example, JP-A-58-180657, JP-A-58-180658, and JP-A-58-18065.
No. 9, JP-A-60-166443, it is possible to use a nonwoven fabric manufacturing apparatus disclosed in JP-A-1-48857 and the like,
The heat fusion at the yarn intersection is not limited by the means, and a hot air fusion method, a heat roll nip method, a hot plate contact method, or the like can be adopted. In addition, by performing the heat treatment in a temperature range equal to or lower than the melting point of the core resin, it is possible to securely fuse and integrate without causing unnecessary thermal deterioration.

In the present invention, the laminate coating layer 3 is laminated on one or both sides of the nonwoven fabric 2 formed of the composite yarn. As the laminating method, known techniques such as an extruding laminating method, a dry laminating method, and a thermocompression laminating method can be adopted. Since the laminating resin is laminated in a molten state, and can be processed at a higher speed, it is most preferable that the laminating resin is laminated on both surfaces of the nonwoven fabric 2 by an extrusion laminating method. Here, the thickness of the laminate coating layer 3 can be arbitrarily set, but is preferably 15 to 40 μm.

A pressure-sensitive adhesive layer 4 is formed on at least one surface of the laminate coating layer of the tape base material thus obtained to form a pressure-sensitive adhesive tape 1 shown in FIG. A known material such as acrylic, silicon, vinyl, natural rubber, or synthetic rubber may be used, and a predetermined basis weight may be applied according to each application.

[0019]

According to the present invention, the intersections of the warp yarns 5 and the weft yarns 6 of the nonwoven fabric 2 in which the composite yarn groups are arranged and superimposed do not shift, and in particular, by firmly fixing the warp yarns 5, The load in the cutting of the adhesive tape 1 in the weft direction is reliably applied to the warp 5, and the hand-cutting property is improved. In addition, since the warp yarns 5 present on the fractured surface are on the same plane, the adhesive tape 1 can be made to have a cut surface without fluff without unevenness in tearing strength.

[0020]

[Embodiment] Hereinafter, an embodiment will be described.

Example 1 Polypropylene (MFR = 1.7,
Melting point: 156 ° C.), polyethylene-polypropylene random copolymer (MFR = 4.0, melting point: 136 ° C.) selected as a low melting point component for the outer shell portion 8, extruded in a molten state at 250 ° C. by a T-die flat method from a multilayer T-die, and cooled. After forming a multilayer film, the film is cut into tapes and stretched at a stretching temperature of 130 ° C., an annealing temperature of 138 ° C. and a stretching ratio of 5.2 by a hot roll stretching method, and the layer ratio is 1: 8. A three-layer composite flat yarn having a fineness of 80dr and 240dr at a ratio of 1: 1 was obtained.

The weft yarn group in which 240dr composite flat yarns are arranged as 18 wefts / inch (separation 0.7 mm) as wefts 6
A group of warp yarns arranged at a ratio of 38 yarns / inch (separation: 0.4 mm) with a composite flat yarn of 0dr as warp 5 are superposed on each other at right angles to each other. To form a nonwoven fabric 2.

In forming the laminate coating layer 3 on the nonwoven fabric 2, polypropylene (MFR = 22.0) was melted at a melting temperature of 30.
At 0 ° C., a tape base was formed by extrusion laminating at a thickness of 20 μm as a first laminating layer on the warp side and 38 μm as a second laminating layer on the weft side, An example in which a first laminating layer surface of the tape base material is subjected to a back surface treatment and a second laminating layer surface is subjected to a corona discharge treatment and then a synthetic rubber-based pressure-sensitive adhesive layer 4 is provided. Thus, one adhesive tape was obtained.

Comparative Example 1 Fineness of composite flat yarn used in Example 1 was 80dr and 240d
Using a woven fabric having a density of 38 × 18 yarns / inch and plain heat-welding at the intersections, using a woven fabric each having a density of 38 × 18 yarns / inch, and a laminate coating layer and a pressure-sensitive adhesive The one in which the layer was formed was designated as Comparative Example 1-1. In addition, polypropylene (M
FR = 1.7, melting point 156 ° C) Single layer flat yarn with a fineness of 80dr
Using a woven fabric plain woven at a density of 38 x 18 yarns / inch using a single-layer flat yarn with a fineness of 240dr as the weft, and a laminate coating layer and pressure-sensitive adhesive One having the agent layer formed thereon was taken as Comparative Example 1-2.

Example 2 A high-density polyethylene (MFR = 1.
2. A low-density polyethylene (MFR = 4.0, melting point 110 ° C) is selected as a low-melting point component for the outer shell 8, and extruded from a multilayer circular die at 220 ° C by inflation method in a molten state and cooled. After being formed into a multilayer film, the film was cut into tapes, and stretched at a stretching temperature of 115 ° C., an annealing temperature of 125 ° C., and a stretching ratio of 5.5 by a hot plate contact stretching method, and a layer ratio of 1:
Composite flat yarn with three layers of fineness of 150dr and 450dr with 6: 1
I got it.

A weft yarn group in which 450dr composite flat yarns are arranged as wefts 6 at 12 yarns / inch (separation 0.6 mm),
A group of warp yarns arranged at 50 yarns / inch (separation 0.5 mm) as composite warp yarns with 50dr composite flat yarns 5 are superimposed on each other at right angles to each other, and the intersection is heated at 115 ° C. by a heat roll nip method. The non-woven fabric 2 was formed by fusion.

In forming the laminate coating layer 3 on the nonwoven fabric 2, low-density polyethylene (MFR = 15.0) is melted at 280 ° C. by extrusion lamination to form a first laminating layer on the warp side as 25 μm. With a thickness of 35 μm as a second laminating layer on the weft side to form a tape base,
An example in which a first laminating layer surface of the tape base material is subjected to a back surface treatment and a second laminating layer surface is subjected to a corona discharge treatment and then a synthetic rubber-based pressure-sensitive adhesive layer 4 is provided. 2 was obtained.

Comparative Example 2 The fineness of the composite flat yarn used in Example 2 was 150 dr and 450 denier.
Using a woven fabric which is plain woven at a density of 30 × 12 yarns / inch using each of the dr weft yarns at a density of 30 × 12 yarns / inch and heat-sealed at the intersections, a laminate coating layer and a pressure-sensitive adhesive One in which the layer was formed was referred to as Comparative Example 2-1. Using a single-layer flat yarn with a fineness of 150dr made of high-density polyethylene (MFR = 1.2, melting point 132 ° C) with a fineness of 150dr for the warp and a single-layer flat yarn with a fineness of 450dr for the weft, a density of 30 x 12 yarns / inch Using a woven fabric woven in plain weave, a laminate coating layer and a pressure-sensitive adhesive layer were similarly formed as Comparative Example 1-2.

The performances of the thus obtained adhesive tapes of Examples and Comparative Examples are summarized in Table 1 in terms of the tensile strength in the longitudinal direction, the tear strength in the weft direction, and the hand-cutting property. In addition, the measurement of the tensile strength
JIS-L1096, tear strength was JIS-P8116, and hand-cutting property was measured by measuring the fluffiness of the cut surface (Yes: x, slightly yes: Δ, no: ○).

[0030]

[Table 1]

From Table 1, it can be seen that this example has sufficient strength in the warp direction as an adhesive tape, has improved tearing strength in the weft direction and is easy to cut by hand, and the cut surface is fluffy. It is recognized that the adhesive tape has no quality and is of good quality.

[0032]

According to the present invention, composite yarns having a core having a high melting point component and a skin portion having a low melting point component are arranged and overlapped by the above-mentioned structure, and the crossing portion is heat-sealed to prevent misalignment. By using the non-woven fabric structure for the tape base, the warp fixing force to the weft and the laminating coating layer is improved,
Thereby, while maintaining sufficient tensile strength in the warp direction of the adhesive tape, the load in the cutting in the weft direction is reliably applied to the warp, and the hand-cutting property is improved.

Further, since the nonwoven fabric has a structure in which a large number of two arranged yarn groups are superposed on each other in a state of being orthogonal to each other to form a warp yarn, the warp yarn groups corresponding to the cut surface along the weft are all the same. A beautiful cut surface without unevenness in the tearing strength in the weft direction and having no fluff by having the same degree of bondability with the warp intersection and the laminating coating layer and the degree of warp heat deterioration. And a high-quality adhesive tape exhibiting the following characteristics.

[Brief description of the drawings]

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

FIG. 2 is a partial plan view of a conventionally used woven fabric.

FIG. 3 is a perspective view of a nonwoven fabric used in the present invention.

FIG. 4 is a partially enlarged perspective view of a nonwoven fabric used in the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Adhesive tape 2 Nonwoven fabric 3 Laminate coating layer 4 Pressure sensitive adhesive layer 5,5 'Warp 6,6' Weft 7 Core part 8 Outer part

Claims (1)

(57) [Claims] 1. A tape base comprising a fabric and a laminate coating layer 3 laminated on one or both surfaces of the fabric, and a pressure-sensitive adhesive layer formed on at least one of the laminate coating surfaces. In the pressure-sensitive adhesive tape 1 provided with the composite yarn 4, the cloth is made of two or more kinds of synthetic resins having different melting points, of which a composite yarn having a core 7 as a high melting component and an outer skin 8 as a low melting component. A number of two yarn groups arranged substantially in parallel are arranged so as to be orthogonal to each other and overlapped with each other to form a warp yarn,
An adhesive tape characterized by being a nonwoven fabric 2 which is heat-fused in a temperature range not lower than the melting point of the resin of the outer skin portion of the yarn and not higher than the melting point of the core portion resin, and the intersection is fused and integrated.