JPH01104849A - Base cloth for sticking tape - Google Patents

Abstract

PURPOSE: To obtain a base fabric for adhesive tapes good in sticking operability and hand cuttability, with no mechanical strength drop when gotten wet, free from thickness unevenness and uneven feel, and good in appearance by using a polyester bulk yarn having each a specific tenacity and elongation, interlacing degree and bulkiness. CONSTITUTION: This base fabric for adhesive tapes widely applicable e.g. as packaging materials or temporarily fixing/holding materials in various assembly activities is obtained by using, at least as a warp, a polyethylene terephthalate bulk yarn having the following properties: 10 <= elongation(%) <=17, 12<= tenacity (g/d) ×elongation(%)<1/2> <= 17, 60 <= interlacing degree (points/m), and 25 <= bulkiness (cm<3> /g).

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a base fabric for adhesive tapes, and particularly to a thick base fabric for adhesive tapes.

(Prior Art) In recent years, adhesive tapes have come to be widely used as packaging materials and temporary fixing and holding materials in various assembly operations.

One of the characteristics required of an adhesive tape is that it can be easily torn by hand in the width direction.

In order to improve the ease of hand cutting, the warp yarns of the base fabric are
, 3 Use thread with a thickness less than a crane (Jikko Sho 52)
-58067 Publication), use of copolymerized modified polyester flat yarn for the warp of the base fabric (Japanese Unexamined Patent Publication No. 58-58
-91845), low elongation obtained by hot drawing highly oriented undrawn polyester yarn spun at high speed into the warp of the base fabric;
It has been proposed to use low toughness polyester filaments (Japanese Unexamined Patent Publication No. 61-218676). However, all of these proposals used base fabrics using flat yarns. This relates to so-called thin adhesive tapes, and while such thin adhesive tapes have advantages such as good appearance after application and no unevenness, they are soft and tend to wrinkle when applied. This problem is likely to occur, resulting in poor pasting workability.

In an attempt to solve the problems of such thin adhesive tapes, thick adhesive tapes have also been developed.

Spun rayon yarn has conventionally been used as the base fabric for thick adhesive tapes.

(Problems to be solved by the invention) A thick adhesive tape using spun rayon yarn as the base fabric is
Although the workability of pasting is good, the strength when wet is reduced to 45-55% compared to when dry, the thickness of the base fabric is uneven, the surface is not flat and has an uneven appearance, and the appearance is poor. There are problems such as poor adhesiveness and the tendency for an excessive amount of adhesive resin to adhere.

The purpose of the present invention is to solve the above-mentioned problems of conventional thick adhesive tapes, to have good application workability and manual tearability, no loss of strength when wet, and an appearance without uneven thickness or unevenness. An object of the present invention is to provide a base fabric that can be used as a good adhesive tape.

(Means for Solving the Problems) As a result of intensive studies to achieve the above object, the inventors of the present invention have found that a polyester bulky processed yarn having a specific strength and elongation, degree of entanglement, and bulkiness is used as a base fabric. The present invention was achieved by discovering that it can be used for.

That is, the present invention substantially consists of polyethylene terephthalate, and 10≦Elongation (%)≦17 12≦Strength (g/de) X ma (%)≦1
This is a base fabric for an adhesive tape, characterized in that a bulky textured yarn satisfying the following conditions is used as at least the warp yarn: 760≦degree of entanglement (ke/m) 25≦bulkness (cd/g).

The polyester used in the present invention consisting essentially of polyethylene terephthalate is one in which 95 mol% or more of its repeating units are composed of ethylene terephthalate, and less than 5% is composed of ethylene terephthalate, even if less than 5% is copolymerized with other components. Commonly, for example, copolymerized acid components include phthalic acid, isophthalic acid,
Adipic acid, oxalic acid, sebacic acid, suben+')ic acid,
2 such as glutaric acid, pimelic acid, fumaric acid, and succinic acid.
Examples include basic acids. It may also contain an oriented crystal inhibitor such as benzoic acid and hydroxybenzoic acid, and a polymerization regulator such as acetic acid and propionic acid. On the other hand, as the glycol component, polymethylene glycol having 2 to 10 carbon atoms, such as trimethylene glycol, cyclohexane dimetatool, etc., is used. In addition, as a modifier, 5-oxymethyl hexahydroisophthalate, benzene-1,3,
It may also contain a small amount of 5-1-ricarboxylic acid or the like. Furthermore, a matting agent, a color stabilizer, etc. may be included as additives.

The polyester bulky processed yarn used in the present invention is
In order to make the adhesive tape easy to tear by hand in the width direction, that is, to improve the hand tearability, the elongation is 10.
~17%, and the strength index, that is, strength x JW pressure, is required to be 2 to 17. If the elongation and strength index are higher than the above ranges, the adhesive tape will have poor hand tearability, fraying will occur at the cut end after tearing, and a beautiful cut end will not be obtained. Also,
Bulky polyester yarns with elongation and strength index lower than the above ranges frequently break and fluff during the manufacturing process, making it difficult to stably manufacture them.

Furthermore, the bulky polyester yarn used in the present invention has been subjected to an interlacing treatment, and the degree of entanglement must be 60 threads/m or more. By setting the degree of entanglement to 60 knots/m or more, it is possible to weave without twisting or sizing without going through a sizing process, and the weavability of the base fabric is significantly improved. It also contributes to improved adhesion when laminating a resin layer to a base fabric and improved hand tearability when used as an adhesive tape.

Further, the bulky textured polyester yarn in the present invention needs to have bulkiness of 25 cffl/g or more. If the bulkiness is less than 25c+a/g, the thickness of the adhesive tape cannot be made sufficiently thick, and wrinkles are likely to occur during application, resulting in poor application workability.

Here, the bulkiness was measured as follows (directly).

Frame circumference 90 (J reel bulky thread sample 180 cm
After winding it into a skein shape and dry-heating it at 180°C for 5 minutes under a load of 6 g, the bulky textured yarn was loosened to remove entanglements caused by shrinkage between the yarns, and then the groove l of the measuring device shown in the figure was Insert the sample into the plate, place a 6g flat weight 2 on it,
Read scale 3 and measure the volume of the sample V (c+J). Note that the length of the groove 1 of the measuring device is 10 cm, and the width is 1
c111% The bottom R is 0.5 cm, the length of the flat weight 2 is 12C11, and the width is 0.9 cm.

Next, both ends of the sample were cut off to match the sides of groove 1, and the weight W (g) of the sample after cutting was measured.
V/W (cj/g) is defined as bulkiness.

As a typical manufacturing method for the bulky textured polyester yarn used in the present invention, the birefringence index (Δn
) is 0.02 to Q, Q8, highly oriented undrawn polyester yarn is fabricated with a plurality of friction disks partially overlapping and intersecting three or more parallel rotating shafts rotating in the same direction. A processing device, wherein the surface roughness of the friction disk is 7S or more and 30
3 or less, heating and stretching is carried out at a stretching ratio of 73% to 85% of the maximum stretching ratio, and the ratio of the rotational peripheral speed of the friction disk to the yarn speed (D /Y) is 2.4 or more, a stretching and simultaneous temporary combustion process is performed, and then a fluid entanglement process is performed. in this way,
The birefringence index (Δn) of the undrawn yarn is selected within the range of 0.02 to 0.08. When Δn is less than 0.020, heat resistance is poor and thermal deterioration is likely to occur during drawing and temporary combustion processing (thus, yarn breakage is likely to occur).When Δn exceeds o and oso, crystallization is promoted. When the polyester undrawn yarn is subjected to drawing and simultaneous false twisting, the crystals are partially destroyed and the molecular chains need to be rearranged, so there are extremely many fuzz-broken yarns.
This is not preferable because it becomes difficult to obtain the physical properties of 10≦elongation (%)≦17 defined by the present invention. Therefore, the undrawn polyester yarn used here has a birefringence of 0.020 or more O,
OSO or less is preferable, and the corresponding spinning speed varies depending on the polymer additive, single fiber De, spinning draft, etc., but is approximately 2000 m/min to 4500 m/min, preferably 2500 m/min to 4000 m/min. be.

Furthermore, the surface roughness of the friction disk is set to 7 to 30S, which is rougher than that of a conventional friction disk, and the D/Y is set to 2.4 or higher, which is higher than normal conditions. As a result, the polyester fiber surface is actively rubbed. As a result, the obtained polyester bulky processed yarn tends to have low strength and low elongation, and falls within the range defined by the present invention, 10≦elongation (%)≦1.
A bulky processed polyester yarn with 7.12≦strength (g/d) x force 11 and i≦17 can be easily obtained. If the surface roughness of the friction disk is less than 7S, it will not be possible to actively rub the polyester fiber surface, and it will be difficult to reduce the strength and elongation.
It is difficult to obtain bulky processed polyester yarn with the physical properties specified in the present invention. In addition, when the surface roughness exceeds 3O3, the variation in roughness becomes large, and as a result, the variation in strength and elongation of the obtained polyester bulky yarn becomes large, making it difficult to obtain a product of satisfactory quality. Hateful. Furthermore, a large amount of white powder (scum) from the polyester and spinning oil is generated around the friction-type false twisting device, which is unfavorable in terms of production process control.

Next, the film is heated and stretched at a stretching ratio of 73% or more and 85% or less of the maximum stretching ratio. If the maximum stretching ratio is less than 73%, it is difficult to reduce the elongation. Conversely, the maximum stretching ratio of 8
If it exceeds 5%, yarn breakage will occur frequently during stretching and simultaneous false twisting, and the resulting bulky polyester yarn will have a large amount of fuzz, which is not preferable.

In order to obtain the elongation and strength index specified in the present invention, in addition to the above-mentioned methods, methods using polyester with low intrinsic viscosity, methods employing specific spinning and stretching conditions, methods applying alkali treatment, methods using abrasive materials, etc. Conventionally known methods, such as a method of abrasion treatment, can be used.

Furthermore, in addition to the above-mentioned false twisting process, conventionally known methods such as fluid jet bulking process and push bulking process can be employed for the bulking process.

Furthermore, the entangling process can be performed using a conventionally known fluid entangling process apparatus such as an interlacing process apparatus.

(Example) Hereinafter, the present invention will be explained in further detail by giving examples.

Examples 1 to 6, Comparative Examples 1 to 5 Polyethylene terephthalate with an intrinsic viscosity of 0.64 was
Undrawn polyester melted at 95 °C, spun at a spinning speed of 3300 m / min from a spinneret with 24 nozzles and wound, with a birefringence (Δn) of 0.045 and a maximum draw ratio of 2.2. Got the thread. The amount of molten polymer discharged from the spinneret is determined when the processed yarn fineness after drawing and simultaneous false twisting is 100.
It was adjusted so that de.

Next, this undrawn yarn was subjected to stretching and simultaneous false twisting using a friction false twisting device, and then subjected to fluid entanglement treatment and wound up. At that time, the draw ratio (DR), the ratio of the rotational circumferential speed of the friction body to the yarn speed (D/Y), and the fluid pressure during the fluid entanglement treatment were variously changed as shown in Table 1. The surface roughness of the friction disk of the friction false twister was IO3. Other drawn false twisted yarns were as follows.

Heater length: 2m Heater temperature: 220℃ Processing speed: 600m/min These polyester crimped yarns were warped without applying glue.
Woven in a water jet loom.

The fabric density at this time was a warp density of 45 yarns/inch and a weft yarn density of 33 yarns/inch, and the same false twisted yarn was used for the weft yarns. Next, the obtained base fabric was made into an adhesive tape in an adhesive tape manufacturing process, and then a tear test was performed in the radial direction, and the appearance of the applied tape was also observed. These results are also listed in Table 1.

As is clear from Table 1, adhesive tapes within the range specified by the present invention have good hand tearability and appearance, and are also excellent in simultaneous stretching and simultaneous false twisting and weaving properties.

(This page, the following margins) Examples 7 to 10, Comparative Example 6 The undrawn polyethylene terephthalate yarn melt-spun in Example 1 was stretched 1.65 times at 65°C, and then rubbed against a '20S rough friction body. and then overfeed rate 5
It was supplied at 0% to a fluid injection bulking device described in Japanese Patent Publication No. 35-6684, and subjected to bulking. At this time, the fluid pressure applied to the fluid injection bulking device was variously changed as shown in Table 2 to obtain polyester crimped yarns with different bulkiness.

These polyester crimped yarns are used for the warp and weft,
Warped without applying glue, using Waterjet/Iz-me, warp density 45/inch, weft density 33/inch,
It was woven so that Next, the obtained base fabric was used as an adhesive tape, and a tear test was conducted in the warp direction, and the appearance of the attached tape was also observed. The results were as shown in Table 2. As is clear from Table 2, the adhesive tape of the present invention had good hand tearability and good appearance.

(This page, the following margins) (Effects of the invention) The adhesive tape base fabric of the present invention has good application workability and hand tearability, no loss of strength when wet, and no uneven thickness or unevenness. An adhesive tape with a good appearance can be obtained.

[Brief explanation of the drawing]

The figure is a perspective view of the bulkiness measuring device.

Claims (1)

[Scope of Claims] 1. A base fabric for an adhesive tape, characterized in that a bulky textured yarn substantially made of polyethylene terephthalate and satisfying the following conditions is used as at least the warp yarn. 10≦Elongation (%)≦17 12≦Strength (g/de)×√ [Elongation (%)]≦1760
≦degree of entanglement (ke/m) 25≦bulkness (cm^3/g)