JPH0126349B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a base fabric for an ink ribbon. More specifically, the present invention relates to a method for manufacturing an ink ribbon base fabric that is optimal for ink ribbons used in dot printers.

Conventional line printers or serial printers have type built into the printer, and the ribbon and printing paper are stacked on top of the type and hit with a hammer to transfer the ink from the ribbon to the printing paper and print. Therefore, the gaps between the threads of the fabric, which are usually called lead marks, and which are inevitably created by the reed feathers during weaving, did not have any effect on printing.

However, in recent years, dot printers have been developed that form letters using multiple dots, and in order to form clear letters, extremely thin needles with a pin diameter of 0.3 to 0.4 mm are used to form the dots. has been done. In addition, a dot printer for kanji with many strokes has recently been developed, and since this uses a needle with a smaller diameter, the needle penetrates into the lead mark of the fabric during printing, catching single fibers and generating fuzz. There is a problem of causing such problems.

Therefore, as measures to reduce the number of lead marks, we can create a high-density fabric at the weaving or scouring and setting stage, reduce the number of yarn twists to make the yarn loose,
On the other hand, various attempts have been made to increase the number of yarn twists to improve cohesiveness and reduce the chance of single fibers getting caught, but none of these methods have yielded good results. . In other words, although these methods can reduce the gaps between the threads of the fabric, which are usually called lead marks, and which are inevitably caused by the reed feathers during weaving, they cannot completely eliminate them, and they may cause fuzz to occur during printing. cannot be resolved.

The present inventors completed the present invention as a result of various studies on a method for eliminating lead marks on textiles.

In the present invention, a high-density fabric made of synthetic fiber multifilament yarn with a warp and weft of 20 to 120 deniers, a warp density of 150 to 220 threads/inch, and a weft density of 100 to 140 threads/inch, is scoured and set, and then heated. This is a method for producing a base fabric for an ink ribbon, in which the thickness of the woven fabric after scouring and setting is reduced by 2 to 10% by pressurizing the woven fabric without forming a film, and the woven fabric is apparently free from lead marks.

To further explain the present invention, the greatest feature of the present invention is that the surface is not formed into a film and the apparent This is because the fabric does not allow lead marks.

In other words, the pressurization under heat in the present invention is not just a surface smoothing process like general calendering, but it also smoothes the threads on the left and right sides of the lead mark while avoiding excessive smoothing (filming) of the surface. This is to cause the lead mark to become loose and move, thereby blocking the lead mark.

If the surface of the fabric is not formed into a film and no apparent lead marks are formed by applying pressure under heating as described above, there will be virtually no lead marks, so the needle will penetrate into the lead marks and the single fibers will It will not get caught and cause fuzz. Furthermore, for the same reason, excessive ink is not retained in the lead mark, causing ink stains or increasing the difference between the initial print density and the final print density. In addition, the surface is not filmed, and each thread that makes up this fabric can absorb and retain ink between its constituent fibers, just like normal fabrics, so it can retain a sufficient amount of ink and provide clear images for a long time. It is printable.

In the present invention, the synthetic fiber multifilament fabric is made of thermoplastic fibers such as polyamide fibers and polyester fibers, and the warp and weft yarns are from 20 to
120 denier, warp density 150-220 threads/inch,
A woven fabric having a weft density of 100 to 140 yarns/inch is preferable. These fabrics are usually woven with a plurality of warp yarns being drawn into the reed feathers, so that inter-yarn gaps, usually called lead marks, occur in the warp direction in the fabric portion corresponding to the reed feathers. When this fabric is inked and used as an ink ribbon for a dot printer, the needle of the dot printer gets caught in the gaps between the yarns, causing fuzz.

What is important in the present invention is that by applying pressure under heat to a fabric having such lead marks, the threads are moved and the thickness is reduced, thereby completely filling the lead marks and creating a fabric that does not appear to have any lead marks. That is to say. This is considered a fabric that does not apparently accept lead marks.
This refers to creating a woven fabric that does not form a film and does not show any lead marks when viewed closely.

A heating and pressing means is used to pressurize while heating. Such heating and pressurizing means has a structure that can heat one or more of calenders such as roll calenders, felt calenders, and friction calenders, rolls of continuous adhesive interlining processing machines, or belts. Further, any structure that can be pressurized by steam pressure, air pressure, liquid pressure, dead weight pressure, etc. may be used. Alternatively, it may be a heating and pressurizing means in which one side is fixed and the other rotates.

The heating temperature and pressure may be appropriately selected in combination with the number of times of passing through the heating and pressurizing means, etc., but in general, the heating temperature is preferably 50 to 180°C. When the heating temperature exceeds 180°C, the surface of the fabric becomes a film, which tends to result in poor ink impregnation in the subsequent inking process.

In addition, the pressure conditions should be selected to the extent that the surface of the fabric does not form a film, and usually the gauge pressure is 1.
~5Kg/cm2 is ^sufficient . If the gauge pressure is too high, the fabric will become a film, which is undesirable. In addition, by using a friction calendar or the like to make the rotational speeds of the two rolls different during nipping, a frictional force is applied to the fabric as it passes between the rolls, making it possible to more effectively eliminate lead marks on the fabric. Therefore, it is preferable. The appropriate rotational speed ratio at this time is about 1:1.1 to 2.0; if it is higher than this, the fabric tends to become wrinkled and fluffy.

It is best to use fabrics with such inter-yarn voids that have already been scoured and set. Lead marks can be removed by heating and pressing the fabric with heating and pressing means before scouring or setting. This is undesirable because the lead mark will appear again in the process.

By applying pressure to the woven fabric under heat after scouring and setting, the warp threads on the left and right sides of the lead mark are pressed down and loosened, and the lead marks are visually recognized by moving them thoroughly to fill the gaps between the threads. It disappears. At this time, it is desirable that the thickness of the woven fabric after heating and pressing is reduced by 2 to 10% with respect to the thickness of the woven fabric after scouring and setting. When the thickness reduction rate is 2% or less, the warp yarns on the left and right sides of the lead mark are less likely to come apart or move, and it tends to be difficult to make the lead mark visually unrecognizable.

Furthermore, if the thickness reduction rate is 10% or more, the appearance tends to become very flat and film-like, and the ink absorbency tends to be poor.

The ink ribbon base fabric of the present invention, which has no apparent lead mark, is inked into an ink ribbon. At this time, since the surface of this ink ribbon base fabric is not formed into a film, there is no problem in inkability. Also, when inking on fabrics with regular lead marks,
Since a large amount of ink is retained in these gaps, ink stains increase, and the difference between the initial print density and the final print density becomes extremely large, resulting in a short ink life.However, the ink ribbon base of the present invention When inking cloth, the ink is evenly applied to the cloth, resulting in less ink stains and longer ink life than conventional products.

The ink ribbon inked on the ink ribbon base fabric of the present invention has a pin diameter of 0.1 to 0.2 mm.
With this kanji dot printer, no fuzz will occur due to the pins even after long periods of use.

Next, the present invention will be explained with reference to Examples.

Example 1 Weaving, scouring, and setting were performed using nylon 66 40 denier/34 filament for the warp and weft, and the number of reeds for the warp was 3, and the warp density was 175.
A fabric with a weft density of 115 threads/inch was produced. In this fabric, lead marks could be seen every three reeds. This fabric was heated and pressed at a speed of 2 m/mm at a gauge pressure of 1 Kg/cm ² using a roll calender consisting of a metal roll on one side and a rubber roll on the other side, with the metal roll heated to 130°C.
The thickness reduction rate of the obtained fabric was 3%, and no lead marks could be seen even at a close glance. Cut this into 1/2 inch pieces, ink it,
This was made into an endless ribbon with a circumference of 2m.
This is a kanji dot printer (pin diameter 0.2mm,
As a result of a printing test using 24 pins),
Even when the number of printed lines was 50,000, no fluff was generated due to the pin getting caught. In addition, similar endless ribbons made of woven fabrics before being heated and pressed, and endless ribbons made of woven fabrics treated with a roll calender before setting and then set, have loop fuzz due to pin catching after 10,000 printed lines. confirmed.

Example 2 Weaving, scouring, and setting were carried out using nylon 66 40 denier/34 filament for the warp and nylon 66 70 denier/34 filament for the weft, and the number of reeds was 3. The warp density was 170/inch and the weft. A fabric with a density of 110 fibers/inch was made.
In this fabric, chipping and lead marks were observed every three reeds.

This fabric was passed through a friction calender with a speed ratio of 1:1.5 between the central rubber roll and the upper metal roll heated to 100°C. The thickness reduction rate of the obtained fabric was 7%, and the threads on the left and right sides of the lead marks were separated and moved, resulting in a fabric with no lead marks at all. The endless ribbon made of this woven fabric was extremely suitable for use in dot printers for Kanji characters.

Claims (1)

[Scope of Claims] 1. Both the warp and weft are made of synthetic fiber multifilament yarn with a denier of 20 to 120, and the warp density is 150 to 120.
By applying pressure under heat to a high-density fabric with a weft density of 220 threads/inch and a weft density of 100 to 140 threads/inch after scouring and setting, the thickness of the woven fabric after scouring and setting is reduced by 2 to 10% without forming a film. A method for producing a base fabric for an ink ribbon, characterized in that the fabric is made into a fabric that does not allow any apparent lead marks. 2 Pressure under heating is performed by a heating and pressing means equipped with two or more rolls, and the rotation speed of at least two rolls of the heating and pressing means is set to 1:1.1 to 1:1.1.
2. The method for manufacturing an ink ribbon base fabric according to claim 1, wherein the difference is within a range of 2.0.