JPH0745646B2 - Adhesive tape - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an adhesive tape, and more particularly to an adhesive tape that can be easily cut with fingers and has a beautiful appearance.

[Prior Art] As a high-strength adhesive tape, a base cloth coated with rubber or resin and provided with an adhesive layer is commercially available.

However, since the strength is improved, it is difficult to manually cut it into an arbitrary length. To improve this, JP-A-58-93
Japanese Patent Laid-Open No. 770 and Japanese Patent Laid-Open No. 58-91845 propose to reduce the strength of the warp yarn of the base fabric.

On the other hand, a polypropylene adhesive tape without a base cloth has strength, but it is still difficult to cut it into an arbitrary length, so an example in which an end surface of the wound tape is scratched with a file etc.
58-13680.

[Problems to be Solved by the Invention] However, in an adhesive tape in which the strength of the warp of the woven fabric is reduced, the warp may be easily cut because the warp is equally weak over the entire width of the tape. However, even if it is used for packaging and requires a predetermined strength, it may be cut by vibration, impact, etc., so that it is difficult to exhibit the strength originally required for the adhesive tape. there were.

Further, in the adhesive tape of JP-A-58-13680,
There was a problem that it was difficult to cut straight polypropylene when cutting polypropylene with scratches on the edges.

[Means for Solving the Problems] According to the present invention, there is provided an adhesive tape comprising an adhesive layer, a base cloth layer and a laminate layer, wherein one of two edge lines extending in the longitudinal direction of the adhesive tape or With a grater-shaped working tool having a protrusion with a single ridgeline formed between a rising surface that is a flat surface and a raised surface that is an inclined curved surface on both substantially edge lines, There is provided a pressure-sensitive adhesive tape characterized in that a scar is provided at least penetrating the laminate layer, and a warp is weakened in the base fabric layer.

The adhesive layer may be of a general-purpose type, for example, a conventional adhesive (eg, acrylic adhesive SK Dyne ^# manufactured by Soken Kenkyu Kagaku Co., Ltd.).
701) may be applied.

The base fabric layer may be a woven fabric made of soup, vinylon woven fabric, polyester woven fabric, or a mixed woven fabric made of soup, vinylon and polyester yarn, and is a knitted fabric as long as it exhibits the function of the present invention. May be. In terms of strength, a polyester filament is preferably used for the warp and / or the weft in view of versatility. In addition, the base fabric made of polyester can solve the drawbacks such as the decrease in strength when wet, and the cost reduction can be achieved by using a high-speed loom, such as a water jet loom, and weaving without twisting and sizing. Have advantages.

In the base cloth layer in the present invention, the warp is weakened. Here, in the case of a woven fabric, the warp yarn refers to a yarn in the longitudinal direction of the adhesive tape, and the weft yarn refers to a yarn intertwined with the warp yarn and in the width direction of the adhesive tape (direction crossing the longitudinal direction of the adhesive tape). In the case of a knitted fabric, a yarn extending in the course direction is called warp, and a yarn extending in the well direction is called weft. Then, in order to weaken the warp, various means are adopted as follows.

A woven fabric using at least warp as a polyester multifilament in which an undrawn portion and a drawn portion are mixed in the yarn length direction.

Such a woven fabric is characterized in that its elongation is greatly reduced by heat treatment when it is laminated with a film such as a polyethylene film. In addition, the above-mentioned woven fabric has a physical property of the multifilament when weaving the base fabric, in particular, has an elongation of 50% or more, and thus is a main cause of lowering the high-speed weavability due to no twist and no glue in a water jet room. Since there is almost no fluff, weaving can be performed very efficiently. Further, when the above-mentioned woven fabric is used as a base fabric layer and a film is laminated thereon, an improved peel strength is exhibited. If the peel strength is too small, when the product is made into a product, it is laminated in a roll shape, so that when the pressure-sensitive adhesive tape is used, the base cloth layer and the laminate layer may be peeled off.

The polyester multifilament in which the undrawn portion and the drawn portion are mixed in the yarn length direction can be achieved by appropriately selecting the drawing conditions. That is, it is achieved by setting the temperature of the preheating roller (first roller) lower than the glass transition point (generally, preferably selected at 55 to 65 ° C.) and lowering the stretching ratio. The draw ratio is preferably set to 65 to 75% of the draw ratio set when an ordinary drawn yarn is obtained.

Formula (1) in the molecular chain: (In the formula, X is -SO ₃ Na, -X ', -OR, -R', -OAr, and-
X'is a halogen group, R and R'are alkyl groups, and Ar is an aromatic group which may have the substituent. The binding chain may be in any of the ortho, meta and para positions. m is an integer of 1 to 3, n or l is an integer of 0 to 2. ) A woven fabric using at least a polyester flat yarn having a residue represented by the formula (see JP-A-58-91845).

That is, the polyester has terephthalic acid as a main acid component, an alkylene glycol having 2 to 6 carbon atoms, preferably ethylene glycol as a main glycol component, and a dicarboxylic acid or diol having a residue represented by the formula (1) It is obtained by blending a polyester obtained by copolymerization as a polymerization component or by condensation polymerization of a dicarboxylic acid having a residue represented by the formula (1) and a diol with an ordinary polyester.

Here, as the usable difunctional carboxylic acids other than the above, for example, isophthalic acid, naphthalene dicarboxylic acid, diphenyldicarboxylic acid, adipic acid, sebacic acid, aromatic such as 1,4-cyclohexanedicarboxylic acid,
Examples thereof include aliphatic and alicyclic bifunctional carboxylic acids. Examples of diol compounds other than the above glycols include cyclohexane-1,4-dimethanol, neopentyl glycol, bisphenol A and bisphenol S.
Examples thereof include aliphatic, alicyclic and aromatic diol compounds. The content of the residue represented by the formula (1) is 1
It can be used in the range of up to 30% by weight.

The fineness of the warp or weft is preferably 50 to 100 denier.

A woven fabric using a spun yarn made of rayon fiber, a vinylon fiber as a warp, or a yarn obtained by blending a rayon fiber or a vinylon fiber with a polyester filament.

Highly strong polyester multifilaments may be used for the weft of this woven fabric.

Woven fabric with yarn containing finely scratched polyester multifilaments.

In order to make fine scratches, for example, a method in which flowing metal powder, ceramic powder or the like is collided is preferable.

A filament is manufactured by using a material in which a material incompatible with the polyester is mixed in a raw material at the time of spinning the polyester, and the filament is manufactured to be a woven fabric.

As the substance incompatible with the polyester, an inorganic powder, particularly an inorganic substance having a particle portion is preferable. In this case, the larger the particle size of the inorganic substance, the greater the effect of weakening the filament.

A bundle of polyester multifilaments having a predetermined width and a predetermined thickness are arranged, and at a temperature lower than the melting point of polyester and higher than the glass transition point as shown in FIG. A woven fabric that is pressed and thinned and weakened the pressed portion, and the weakened polyester filament is used as a warp.

In FIG. 10, 19 is a bundle of polyester multifilaments arranged in the width direction, 20 is a pressing roll, and on the surface of this pressing roll, concave grooves and ridges alternate in the direction parallel to the roll axis. It is provided in. 21 is a heating roll,
It is heated to a temperature below the melting point of the polyester and above the glass transition point. By being pressed between the pressing roll 20 and the heating roll 21, a filament in which weak portions and strong portions are alternately arranged is obtained.

The case where the weakened warp yarn is used for the woven fabric has been exemplified above, but when the weakened yarn is used for the knitted fabric, it is preferable to use it for the structure in which the chain loop is formed in the course direction.

The laminate layer is intended to fix the fibers of the base fabric layer to make the surface beautiful and to uniformly adhere silicone for improving the releasability when wound.

As the laminate layer, other than olefin resin such as low density polyethylene (LDPE), low pressure linear low density polyethylene (L-LDPE), high density polyethylene (HDPE), polyethylene terephthalate (PET), polyamide, etc.,
It may be a composite of two or more selected from these in a multilayer, and an anchor coat layer may be provided if necessary.

As a laminating method, any method such as dry, wet, and extrusion may be selected. The preferred material is anchor-coated LDPE, which is excellent in processability, strength and versatility.

The scratch needs to be provided so as to penetrate at least the laminate layer among the three layers. Depending on the type of the base cloth layer, it may be provided even on the base cloth layer.

FIG. 2-A is a cross-sectional view showing an adhesive tape provided with a scratch penetrating the laminate layer, and FIG. 2-B is a cross-sectional view as seen from the direction perpendicular to the cross-section of FIG. 2-A. FIG. 3 is a cross-sectional view showing an adhesive tape having a scar that penetrates the laminate layer and penetrates into a part of the base fabric layer. FIG. 4-A is a cross-sectional view showing an adhesive tape having a scratch penetrating all the layers of a laminate layer, a base cloth layer and an adhesive layer, and FIG. 4-B is a direction perpendicular to the cross-section of FIG. 4-A. It is sectional drawing seen. In FIGS. 2-A to 4-B, 5 is an adhesive tape, 2 is a scar, 6 is a laminate layer, 7 is a base cloth layer, and 8 is an adhesive layer.

The scar in the present invention is provided by pressing, rubbing, tapping or the like with a grater-shaped processing tool as shown in FIG.

As shown in FIG. 7, the grater-shaped working tool in the present invention means that a metal surface 16 is provided with a pseudo-triangular notch 17, and the base of the pseudo-triangular shape is used as a central axis to cut the metal surface. It is a processing tool in which a metal part separated from 16 is raised and a projection 9 is projected. The cut portion of the metal surface 16 remains as a recess 10 (see FIG. 6).

Explaining further, the protrusion 9 of the grater-shaped working tool has a raised surface 11 which is a flat surface, as shown in FIG.
And a raised surface 15 which is an inclined curved surface, and one ridge line 18 formed between the raised surface 11 and the raised surface 15 serves as a cutting edge.

The angle formed by the standing surface 11 which is the surface of the protrusion 9 on the side of the depression 10 with respect to the metal surface 16 is preferably 60 ° or more and 90 ° or less. Such protrusions 9 are arranged in a line in one or more lines, and the metal is quenched and used. FIG. 8 is a perspective view of the processing roll 12 having such a protrusion on its circumferential surface.

When the protrusions 9 of the grater-shaped processing tool are pressed from the side of the laminated layer 6 of the laminated cloth 1, the ridgeline that is the cutting edge cuts the laminated layer 6, and the upright surface 11 straightly enters the laminated layer 6 and the raised surface 15 Spreads the laminate layer 6 to form a scar 2 as shown enlarged in FIG. The plane shape of the scar 2 is a crescent shape composed of a straight line portion 2a that is a cutting line corresponding to the upright surface 15 and a curved portion 2b that is a bending line by the raised surface 15, and is only on both ends of the straight line portion 2a. Since a corner where stress concentration is likely to occur is formed and the corner is sharp and cracked due to the spread by the raised surface 15, it becomes easy to tear along the straight line portion 2a.

In addition, a raised surface when the protrusion 9 enters the laminate layer 6
The fibers of the base cloth layer 7 are stretched and weakened by the pushing and spreading action of the base fabric layer 7, which also facilitates the cutting with fingers.

In the present invention, a grater-shaped processing tool having the projections 9 as described above is used to form the scratches 2 as described above. However, the adhesive tape of the present invention has a base cloth layer 7 having a large tear strength. Therefore, unlike a tape having a single plastic layer, it does not cause inadvertent tearing during handling.

FIG. 9 is an explanatory view showing an example of processing the laminated cloth 1 by using the processing roll shown in FIG. The processing roll 12 and the pressing roll 13 are rotating in the opposite directions at the same peripheral speed while being in contact with each other. The laminated cloth 1 passes through the contact portions of both rolls. At this time, the laminated cloth 1 is pressed by the projections 9 of the processing roll 12,
The scratches 2 are arranged as shown in FIGS. 1A, 1B, and 1C. 14 is an original fabric of laminated cloth.

The tool for imparting scratches is preferably made of a hard material, and in addition to quenched steel, ceramics such as silicon carbide, titanium carbide and silicon nitride can also be used. Further, those obtained by finishing the tool shape with a metal material and then coating it with a thin film of silicon carbide, titanium carbide or the like by a CVD method, a PVD method or the like are also preferable because they have excellent wear resistance and do not deteriorate the sharpness.

Further, regarding the depth of the blade for making a scar, more effect can be exhibited by selecting a proper combination of these materials such as laminating material alone or reaching the laminating material and the base cloth.

It is desirable that the site of the scar is within 5 mm from the one or both edges of the adhesive tape, and within 0.5 to 3 mm.

The distance between the scratches is 1 to 5 mm, and the rows of the scratch groups arranged in the longitudinal direction may be arranged in two or more rows.

The scratch group may be one row or a plurality of rows of two or more rows as long as they are substantially on the edge line. When the plurality of rows are provided, the width of the scratch group is preferably within 5 mm, more preferably within 3.5 mm.

Substantially on the edge line is 3 from the tape edge to the tape width.
Within a fraction of the length.

Even if the pitch l of the scratches as shown in FIG. 1-C is long, the tearing property is exhibited, and the length l can be as long as about 5 mm, for example.

When the base fabric layer is a normal one (a fabric in which the warp yarns are not weakened) with only scratches on the edges, tearing at the initial stage of tearing is easy, but tear strength increases during the tearing and tearing increases. Although difficult in some cases, the pressure-sensitive adhesive tape of the present invention has a great feature that it can be easily torn with a constant tearing force by finger force from the initial tearing to the completion of tearing.

[Examples] Next, examples will be described.

Example 1 Modified polyethylene terephthalate filament drawn yarn 70d / 24f (strength 3.7g / d, elongation 30) in which 2 mol% of entangled 5-sodium sulfoisophthalic acid was copolymerized with the warp.
%), Polyethylene terephthalate stretched yarn as weft 100d / 2
Weaving 4f (strength 5.3g / d, elongation 30%) with warp density of 48 / inch, weft density of 45 / inch (woven cloth width 137cm) without sizing in water jet loom The obtained fabric was used as a base fabric for an adhesive tape.

Here, as shown in FIG. 1, a low-density polyethylene was melt-extruded on the base cloth 7 and a laminate 6 having a thickness of 50 μm was applied to form a laminated cloth 1.

Next, as shown in Fig. 8, 0.5mm at 1.5mm intervals on the outer circumference.
Rotating blades with 7 width blades are arranged in 5 rows at 27 rows,
While winding, two groups of scratches having a width of about 3.5 mm (laminating the laminate layer and the base material cloth layer) were provided.

Thereafter, a pressure sensitive adhesive was applied to form a pressure sensitive adhesive layer 8, and the central portion of the scar group was cut along a cutting line 4 to obtain a pressure sensitive adhesive tape 5 having a width of 3 cm of the adhesive tape.

The product according to the present invention was very easy to cut, and its cut end was also very beautiful.

Example 2 Polyethylene terephthalate (ηsp / c = 0.73) was melt extruded by a usual method and wound at 1500 m / min. Then, it was drawn under the following conditions to obtain a 70d / 24f drawn yarn.

1st roller: 60 ° C Hot plate: 130 ° C Draw ratio: 2.3 times The drawn yarn obtained is a mixture of undrawn part and drawn part in the yarn length direction, and its physical properties are strength: 3.2 g / d, elongation. : 56.5%, and the number of entanglements by the air injection nozzle applied during stretching was 36 / m.

The drawn yarn was warped by a usual method, wound into a beam without sizing, and woven at 420 rpm in a water jet loom. The weft used was a normal polyethylene terephthalate drawn yarn 100d / 48f, and the weaving density at this time was warp / weft = 48/4
It was 5 (the unit is 25.4 mm in each case).

Low-density polyethylene was melt-extruded on the base fabric layer obtained as described above and laminated to a thickness of 50 μm.

Next, as shown in Fig. 8, rotating blades with 6 rows of 0.5 mm width blades at intervals of 2 mm on the outer circumference were arranged in 27 rows at 5 cm intervals, and wound groups with a width of about 3 mm while winding. (The laminate layer and the base cloth layer are penetrated). After that, an adhesive was applied, and the central portion of the scar group was cut to obtain an adhesive tape having a width of 5 cm.

The adhesive tape according to the present invention has very good hand-cutting property, a beautiful cut end, and a warp yarn having a non-stretched portion (thick & thin) and a normal yarn for the weft yarn. It has a high rigidity and is very easy to attach when packing packing materials.

EFFECTS OF THE INVENTION The pressure-sensitive adhesive tape of the present invention has a beautiful appearance because a laminate layer is further laminated on the pressure-sensitive adhesive layer and the base fabric material layer, and the laminate layer is wound by applying a release material. It has excellent releasability. Further, since the adhesive tape of the present invention is provided with a scar substantially on the edge line, the initial force may be small when tearing the adhesive tape with fingers, and further, the warp of the base fabric layer Since it is weaker than the weft, the tearing strength does not suddenly increase on the way, and it is possible to tear straight with a constant tearing force until the completion of tearing. Furthermore, since the scratches are provided on the edges, it is not necessary to excessively weaken the warp, and the adhesive tape can have high strength accordingly.

[Brief description of drawings]

1-A to 1-C show an embodiment of the present invention,
FIG. 1-A is a plan view of a laminated cloth having a scar, FIG. 1-B is a cross-sectional view thereof, and FIG. 1-C is an enlarged view of the scratched partial a in FIG. 1-A. . 2A to 4B show scars of various depths,
Fig. 2-A is a cross-sectional view showing an adhesive tape provided with a scratch penetrating the laminate layer, Fig. 2-B is a cross-sectional view seen from the direction perpendicular to the cross-section of Fig. 2-A, and Fig. 3 shows the laminate layer. A cross-sectional view showing an adhesive tape having a scar that penetrates and penetrates into a part of the base layer, and FIG. 4-A shows an adhesive having a scar that penetrates all layers of a laminate layer, a base cloth layer, and an adhesive layer. FIG. 4-B is a cross-sectional view showing the tape, and FIG. 4-B is a cross-sectional view as seen from the direction perpendicular to the cross-section of FIG. 4-A. FIG. 5 is an enlarged view of the scar. FIG. 6 is an enlarged view of a projection of a processing roll (tool) for making a scar, FIG. 7 is a sectional view showing an example of a process for manufacturing the projection, FIG. 8 is a perspective view of the tool, and FIG. It is an explanatory view showing an example of processing of cloth. FIG. 10 is an explanatory view showing a heat treatment apparatus for heating and pressing the polyester filament at a minute interval to thin and weaken the pressing portion. 1 ... Laminated cloth, 2 ... Scratch, 3 ... Adhesive tape width, 4 ... Cutting line, 5 ... Adhesive tape, 6 ... Laminate layer, 7 ... Base cloth layer, 8 ... Adhesive layer, 9 …… Protrusions, 10 …… Dimples, 11 …… Rising surfaces, 12 …… Processing rolls, 13 …… Pressing rolls, 14 …… Fabric of laminated cloth, 15 …… Rising surfaces, 16 …… Metal surfaces, 17 ・ ・ ・… Notches, 18… ridges, 19… Polyester multifilaments arranged in the width direction, 20… Heating roll.

Claims (1)

[Claims] 1. A pressure-sensitive adhesive tape comprising a pressure-sensitive adhesive layer, a base cloth layer and a laminate layer, wherein one or both of two edge lines extending in the longitudinal direction of the pressure-sensitive adhesive tape are substantially flat. With a grater-shaped processing tool having a protrusion whose one ridge line is a cutting edge formed between a rising surface that is a surface and a raised surface that is an inclined curved surface, a scar that penetrates at least the laminate layer is provided. And a warp yarn is weakened in the base fabric layer.