JP3388315B2 - Base fabric for laminate tape - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a base fabric for a laminated tape. In particular, the present invention is suitable for a laminated tape, such as an adhesive tape, which is required to have hand tearability at an arbitrary position, predetermined strength in the longitudinal direction, and followability to an adherend.

Here, an adhesive tape will be described as an example of the laminating tape, but the present invention is not limited to this, and the present invention is also applicable to a double-sided tape, a decorative ribbon, and the like. Here, the term “laminate” includes not only the case of lamination but also the case where the base cloth is embedded in the adhesive layer and does not form a clear layer.

[0003]

BACKGROUND ART Recently, in packing and packing work using corrugated cardboard and the like, instead of packing using ropes or strings, an adhesive tape has been widely used because of its simplicity.

As an example of the adhesive tape, PE (polyethylene) is used as a base cloth woven with warp and weft (usually plain weave)
There is one formed by laminating one side with a film and then applying a pressure-sensitive adhesive to the other side which is not laminated.

Then, as a base cloth for an adhesive tape, while maintaining strength in the longitudinal direction (longitudinal direction), the lateral direction (width direction)
When laminated, the tear strength in the horizontal direction is low and the vertical direction (longitudinal direction)
Most of them were woven fabrics (plain weave) that were easy to secure the strength of.

As the warp / weft forming yarns of the woven fabric, rayon staple fibers, multifilament yarns, flat yarns (also called slit yarns or split yarns), etc. have been used.

As publicly known documents describing the above technique, Japanese Examined Patent Publication No. 1-41189 and Japanese Patent No. 2623947.26.
35795/2843043, Japanese Utility Model Publication No. 4-694
82 publication.

[0008]

Recently, the adhesive tape base cloth is required to be as thin and lightweight as possible. However, there is a limit in the woven fabric (textile), especially in the case of using the staple yarn. Therefore, a knitted fabric (knitted fabric) having a large porosity is not known to the inventor of the present invention.

It is presumed that the reason for this is that it is difficult for the knitted fabric to have a low tear strength in the transverse direction and a sufficient strength in the longitudinal direction as in plain weave.

In view of the above, it is an object of the present invention to provide a novel base fabric for a laminated tape such as an adhesive tape which does not use a woven fabric.

[0011]

Means for Solving the Problems As a result of intensive efforts to solve the above problems, the present inventor reduced the transverse tear strength as in the case of the woven fabric with the following constitution, Moreover, it was found that the strength in the longitudinal direction can be secured,
The inventors have come up with a base fabric for a laminated tape having the following structure.

[0012] A base fabric formed of warp knitted fabric, which is used for a laminating tape, wherein the warp knitted fabric is formed of warp yarns, and the weft yarns are spread over the entire width of a plurality of parallel independent chain stitches (wales). Is inserted, the warp yarns are formed of multifilaments, and the weft-inserted yarns are formed of flat yarns.

In the above, it is desirable that the tensile strength of the multifilament be smaller than the tensile strength of the flat yarn, because hand tearability can be easily ensured and strength in the width direction can be easily ensured.

When the multifilament is made of polar fiber and the flat yarn is made of non-polar film, the above constitution can be easily achieved and the application to an adhesive tape becomes easy.

Usually, the polar fibers are polyester fibers and the non-polar film is a polyolefin film.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below. Here, a case where the laminate tape is applied to an adhesive tape will be described as an example.

The laminated tape base fabric of this embodiment is
As shown in FIGS. 1 and 2, it is a base fabric formed by warp knitting fabric, and the weft insertion yarn is formed over the entire width of a large number of independent chain knitting (wales) 14 in which the warp knitting fabric is formed of warp yarns 12. 1
6 is the inserted tissue.

Here, the "warp knitting" is to guide a warped warp to a yarn guide needle parallel to the needle, and entangle the warp with a knitting needle to perform a knitting motion. Opening and closing can be made by tying the thread around the needle. When one thread is always entwined with one needle, a chain of loops can be formed into a string shape in the wale direction. This is called chain stitch. And, usually, if chain stitches are made with each needle, they do not become cloth-like independently, so it is necessary to move the reed so that the thread entangles to one of the left and right needles at each timely course. Generally, in warp knitting, one wale is not made of loops of the same warp. (See “Textile Engineering II Braid” edited by Japan Textile Industry Education Research Institute, published by Jikkyo Shuppan Co., Ltd., p. 14 to 15.) However, in the present invention, one wale is used from the viewpoint of ensuring hand-cutability at an arbitrary position. 14 is an independent chain knitted loop 14a made of the same warp yarn. Here, the length (major axis) of the loop 14a is 1 to 6 mm, and
The density of each wale is 8-28 / inch (preferably 1
2 to 28 lines / inch). The loop density is 4 to
25 pieces / inch (preferably 8 to 25 pieces / inch).
If the wale / loop density is too coarse, it is difficult to obtain the base fabric strength. Conversely, if the wale / loop density is high, the base fabric strength can be obtained, but the number of wale loops is increased and the productivity is increased. Lead to a decline.

In the present invention, the warp yarn 12 is formed of a multifilament, and the weft insertion yarn 16 is formed of a flat yarn. Here, the width of the flat yarn may be such that it has an independent loop deviation preventing action of the wale, and is 50% or more, preferably 70% or more, and more preferably 85% or more of the inner major axis of the normal loop 14a.

If the ratio of the flat yarn (weft insertion yarn) 16 to the loop 14a is too small, the effect of preventing the loop deviation of the independent wales becomes difficult (the alignment of the wales loops decreases), and the width direction. It leads to variations in strength, and adversely affects hand tearability. The upper limit is the width (normally
99 to 98% or less of the major axis inside the loop). When it is more than that, it becomes difficult to carry out the side loading operation, and the flat yarn which is the side loading thread 16 is bent or bent,
The inside of the loop 14a is easily scratched by the edge of the flat yarn on the side-by-side insertion work site, and a defective product is likely to occur.

The weft insertion yarn 16 is usually put in all the loops 14a as shown in FIG. 1, but as shown in FIG.
Every 3rd is optional. Weft insertion thread 16 for all loops 14
When the one that is not included in a is applied to the double-sided tape as shown in FIG. 5, the connecting area of the upper and lower adhesive layers 26a and 26b increases, and the adhesive layer holding force increases. In addition, in FIG. 5, 30 is a peeling tape.

Here, the multifilament is a collection of many long fibers (monofilaments), which is easy to handle and easy to secure strength.

The flat yarn includes a split yarn and a slit yarn.

The split yarn is prepared by slitting a film produced by a T-die or an inflation type film-forming machine into an appropriate width to form a tape, and then stretching it so that the molecules are oriented sufficiently in one direction to make it easy to tear. Fine filaments that are finely cleaved into fibers by physical and mechanical forces. The slit yarn means a film obtained by slitting and then stretching. ("Textile Handbook" edited by the Textile Society of Japan (Sho 43-11-30) Maruzen, pp. 892-8.
94) Here, the reason why the multifilament is used as the warp is that it is easier to obtain the same strength with a thin thread as compared with the staple fiber (stiff) thread, and it is possible to make the base cloth thin and, compared with the monofilament, This is because the tearability is good and the hand tearability is easily secured.

The use of the flat yarn as the weft insertion yarn is for securing the above-mentioned loop alignment, but also has the following secondary effects.

Since the flat yarn has a quadrangular cross section, the base cloth can be made thin and smooth, the smoothness (uniformity) of the pressure-sensitive adhesive layer can be increased, and as a result, the amount of adhesive used can be increased. Can also be reduced.

In order to obtain the same strength in the width direction, the number of weft insertion yarns required is smaller than that of filament yarns, which leads to improvement in productivity.

It is desirable that the tensile strength of the multifilament be smaller than the tensile strength of the flat yarn from the viewpoint of ensuring the hand-cutting property.

For example, the above multifilament (warp)
When polyester fiber is used as, the tensile strength (JIS L 1095) of each is usually 40 to 400 gf.
(0.392 to 3.92N), preferably 82 to 300gf (0.80 to
2.94 N), more preferably 125-250 gf (1.225-
2.45N), the latter 800-2300gf (7.84-22.54)
N), preferably 1000 to 2100 gf (9.81 to 20.6)
N).

For example, the above multifilament (warp)
The denier number when using a polyester fiber is 10 to 100 d (desirably 20 to 75 d, more desirably 30 to 55 d). Further, when using PE slit yarn as the flat yarn (weft insertion yarn), the denier number is 200 to 400 d (desirably 230).
˜370d, more preferably 250-350d).

When the multifilament is made of polar fiber, the strength can be easily expressed with a relatively thin thread, and the base cloth can be made thin, and when it is used as a base cloth for an adhesive tape, it is adhered to a pressure-sensitive adhesive. It becomes easy to secure the property.

Further, when the flat yarn is made of a non-polar film, it is easy to ensure water resistance and, when it is used as a base fabric for an adhesive tape, it is easy to ensure adhesiveness with a laminate film (usually a PE film). Moreover, it contributes to the weight reduction of the base cloth.

As the polar fiber, polyester fiber (polyethylene terephthalate fiber), polyamide fiber (6
-Nylon, 66-Nylon), viscose rayon,
Acetate fibers, polyvinyl-col-based synthetic fibers (vinylon), polyurethane fibers and the like can be used, but polyester fibers are desirable because they are superior in water resistance to polyamide fibers and the like and are well balanced in other physical properties.

Polyolefin films such as polyethylene film, polypropylene film, polybutylene film, and copolymer films thereof can be used as the non-polar film as the laminate film. It has an adverse effect on sex) and is desirable from the viewpoint of flexibility balance.

The base fabric for laminated tape having the above structure is knitted using the multifilament (warp) 12 and the flat yarn (weft insertion yarn) 16.

From the knitted base fabric 18 , as shown in FIG.
A PE film is extruded from both sides of the base fabric 18 to form a laminate layer 20, and a double-sided laminated tape 22 is prepared. Incidentally, as shown in FIG. 4, a single-sided laminate 24 in which the laminate layer 20 is formed on only one side may be used.

Then, in the double-sided laminated tape having the laminated layers 20 formed on both sides, a pressure sensitive adhesive is applied to any one side to form the adhesive layer 26 to manufacture an adhesive tape.

In the case of a single-sided laminated tape having the laminate layer 20 formed on one surface, a pressure-sensitive adhesive is applied to the side opposite to the surface on which the laminate layer 20 is formed to form an adhesive layer 26 to produce an adhesive tape.

Table 1 shows the strength and elongation of the multifilament and flat yarn usable in the present invention.

[0040]

[Table 1]

[0041]

EXAMPLES In order to confirm the effects of the present invention, a base fabric for laminating tape was prepared as follows.

Polyester 30d multifilaments and polyethylene 300d flat yarns shown in Table 1 were used as the warp yarns and the weft insertion yarns, respectively, with a wale density of 24 yarns / inch and a loop density of 17 yarns / inch,
A base fabric having the constitution shown in FIG. 1 was prepared.

Then, PE films on both sides of 0.1 mmt
Was extruded into a laminated tape.

Hand-cutability was confirmed for this laminated tape, but it was good. In addition, tensile strength (JIS L 10
It was confirmed that 9 kgf (88.2 N) / 25 mm is sufficient for the 96 A method).

[Brief description of drawings]

FIG. 1 is an enlarged model diagram showing an embodiment of a base fabric of the present invention.

FIG. 2 is an enlarged model diagram showing another form of the same.

FIG. 3 is a vertical cross-sectional view of an adhesive tape in which the base cloth of FIG. 1 is laminated on both sides.

FIG. 4 is a vertical cross-sectional view of an adhesive tape which is also laminated on one side.

5 is a vertical cross-sectional view of a double-sided tape using the base fabric of FIG.

[Explanation of symbols]

12 warp 14 Independent Chain Edition (Wale) 16 weft insertion yarn 18 base cloth 20 Laminating layer 26 Adhesive layer

Claims (6)

(57) [Claims] 1. A base fabric used for a laminating tape, which is formed of a warp knitted fabric, wherein the warp knitted fabric is crosswise across the entire width of a plurality of independent chain stitches (wales) formed of warp yarns. A base fabric for a laminated tape, which is a weft-insertion structure in which a weft insertion yarn is inserted, wherein the warp yarn is formed of a multifilament and the weft-insertion yarn is formed of a flat yarn. 2. The base fabric for a laminated tape according to claim 1, wherein the flat yarn has a width occupying 50% or more of the link inner major axis of the independent chain knitting. 3. The tensile strength of the multifilament is
The base fabric for a laminated tape according to claim 2, which has a tensile strength lower than that of the flat yarn. 4. The base fabric for a laminated tape according to claim 3, wherein the multifilament is made of polar fiber, and the flat yarn is made of non-polar film. 5. The base cloth for a laminated tape according to claim 4, wherein the polar fiber is a polyester fiber and the non-polar film is a polyolefin film. 6. The laminate tape base fabric according to claim 1, wherein the laminate tape is an adhesive tape.