JPH01306273A - Ink ribbon - Google Patents

Abstract

PURPOSE:To remarkably eliminate the abrasion of a printing wire of an impact printer and to improve the characteristic of printing density on a large scale in a near infrared region, by mixing graphite into ribbon ink employing organic pigment, by a predetermined concentration. CONSTITUTION:In an ink ribbon made of a ribbon base material and ribbon ink using organic pigment, graphite is contained at 5.0 to 10 weight parts for the ink. As the concentration of the graphite is increased, the lifetime of the ink ribbon is elongated. Particularly, when 5 weight parts of graphite is added, the lifetime is extended approximately twice. When 10 weight parts of graphite is added, the lifetime is elongated as much as 2.5 times. However, if the graphite is added 10 weight parts or more, the fluidity of the ribbon ink is worsened, and it becomes difficult to apply or impregnate the ink uniformly into a base cloth of the ink ribbon.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to an ink ribbon.

(Prior art) In recent years, impact printers, which have cost advantages and are capable of high-speed printing on various media, have been used in a wide variety of applications, including peripheral terminal devices for information processing systems as man-machine interfaces. In particular, there is a high demand for high-speed printing. Impact printers that print at high speeds stably process large volumes of information, so one of the important issues is having a highly reliable print head.

In particular, it is strongly desired that the printing wire operate stably over a long period of time without causing wear or damage to the ink ribbon. There is also an iron-based printing wire that is inexpensive and easy to process (Japanese Patent Laid-Open No. 79766/1983).

On the other hand, regarding the high-speed operation of the print head, IEICE Technical Report EMC
As shown in 84-2PP9 and the like, one of the important factors is to reduce the weight of the movable part including the printing wire.

However, since the above-mentioned cemented carbide printing wire contains approximately 70 to 85% by weight of tungsten carbide, its density reaches 13.5 to 14.5 g/cd, making it heavy. It is difficult.

Therefore, in order to achieve high-speed printing, the above density was set to approximately 8 g/ci.
Although it is necessary to use a general iron-based printing wire, which is relatively light in weight, the iron-based printing wire is highly abrasive, shortens the life of the print head, and has the disadvantage of poor reliability.

By the way, the above-mentioned printing wire wear is mechanical appreciative wear caused by the ink ribbon.

The black ink of the conventional ink ribbon is, for example,
-60956 as a colorant, containing a carbon blank, i.e. a vegetable oil as a vehicle;
It is a composition in which carbon black as a coloring material and an oil-soluble dye are added to mineral oil, and auxiliary agents such as a dispersant are further added.

The above-mentioned carbon black mechanically abrades the surface layer of the printing surface of the printing wire by the same action as the abrasive fine particles, causing so-called apressive wear.

(Problems to be Solved by the Invention) In order to avoid such apressive wear, there is also a ribbon ink that uses an organic pigment instead of carbon black. However, printing samples using such ribbon ink are in the near-infrared region (
The printing density with respect to light having a wavelength of 780 to 1500 nm was lower than that of a sample printed with ribbon ink using carbon black, and there was a problem in that a reading error occurred when reading with an OCR device. In other words, the life of the ink ribbon is naturally shortened, and increasing the length of the ribbon to compensate for this increases the cost, and has the drawback of increasing the size of the printer, such as increasing the size of the printer's ribbon cartridge.

An object of the present invention is to provide an ink ribbon that eliminates the above-mentioned drawback of low print density in the near-infrared region.

(Means for Solving the Problems) The present invention provides an ink ribbon consisting of a ribbon base material and a ribbon ink using an organic pigment, in which graphite is contained in an amount of 5.0 to IO parts by weight based on the ink. It is something.

(Function) In the ink ribbon of the present invention, graphite, which is usually used as a solid lubricant, is contained in the ribbon ink using amorphous pigment, and its lubricating action reduces wear and suppresses the above-mentioned print density reduction. This shows that.

(Example) EXAMPLES Examples of the present invention will be shown and specifically explained below.

Note that parts in the following description are parts by weight.

Comparative Example 1 30 parts of vegetable oil and 3 parts of mineral oil were used as vehicles as shown in the table below.
0 parts 2 15 parts of a condensed polycyclic organic pigment (Paliogen Black 0084, manufactured by BASF) as a coloring material, 15 parts of an oil-soluble dye, and 10 parts of a sorbitan fatty acid ester as a dispersant were premixed in a planetary mixer,
This mixture was uniformly kneaded using three rolls to prepare a ribbon ink.

As the ink ribbon base fabric, polyamide fibers such as nylon 6 or nylon 66, or polyester fibers are used.
12 g of the above ribbon ink was uniformly applied and impregnated onto each Möbius ring-shaped endless ribbon-like base fabric. The obtained ink ribbon was attached to an impact printer together with a print head using an iron-based printing wire, and printing was performed. The operating conditions are printing stress 14
kg/-, printing speed 180 times/sec, ink ribbon feeding speed 30 m/sec, and ink ribbon replaced with a new one every 20 million times per 1 printing wire to keep ink consumption constant. did.

Now, regarding the print density of the print sample, the dependence of the print density on the number of prints was investigated as print density (PC3 value) every 2 million prints made by one ink ribbon using a print wire. The printing density is manufactured by Macbeth Co., Ltd.
It was shown by direct pcsj using a PCM-II type printing densitometer and a B filter. For the PC3 value, 1.0 is pure black and 0.0 is pure white, and it is known that a reading error occurs in an OCR device that recognizes a wavelength of 0.3 or less at 950 nm, and this was taken as the lifespan of the ink ribbon.

As shown in Figure 2a, these results show that P
The C3 value was 0.3, indicating the life of the ink ribbon.

Next, regarding the wear of the printing wire, as shown in Figure 3, the length loss Δh on the central axis of the printing wire 1.2 before and after evaluation was measured in microns (hereinafter, this Δh is the length of the printing wire 1.2). (also called axial wear depth). Furthermore, changes in the tip shape of the printing wire were observed using an electron microscope. As a result, the depth of wear in the axial direction of the printing wire after 100 million printing operations was 7-, and the shape of the tip did not change macroscopically as shown in Figure 4, and no unprinted pixels were observed. .

Example 1 30 parts of vegetable oil, 30 parts of mineral oil, pariogen blank KO
08412 parts, 15 parts of oil-soluble dye, 3 parts of graphite with an average particle size of 5.0- and 10 parts of sorbitan fatty acid ester were mixed and the same procedure as in Comparative Example 1 was carried out to obtain an ink, which was used to manufacture an ink ribbon. did. This was installed in a printer, and the printing operation was performed to perform the same evaluation as in Comparative Example 1. As a result, as shown in Fig. 2, the PC3 value reached 0.3 after approximately 12 million printings, and the life of the ink ribbon was reached.

Further, the wear depth after 100 million printing operations was 8n, and the shape of the tip did not change macroscopically, and no unprinted pixels were observed.

Example 2 30 parts of vegetable oil, 30 parts of mineral oil, pariogen blank KO
08410 parts, oil-soluble dye 15 parts, average particle size 5, Ou
5 parts of graphite of rn, 1 part of sorbitan fatty acid ester
0 parts were mixed to obtain an ink, which was used to manufacture an ink ribbon. I attached this to the printer and started printing. As a result of the same evaluation as in Example 1, as shown in Figure 2C, IJ
After 15 million printings, the PC3 value became 0.3 and the life of the ink ribbon was reached.

Further, the abrasion depth after 100 million printing operations was 8 μl, the shape of the tip did not change macroscopically, and the quality of printed pixels did not deteriorate in sharpness in one hue. Furthermore, there was no change in the fluidity of the ribbon ink.

Example 3 30 parts of vegetable oil, 30 parts of mineral oil, Paliogenbrasok KO
An ink was obtained by mixing 848 parts of O8, 15 parts of an oil-soluble dye, 7 parts of On graphite having an average particle size of 5, and 10 parts of sorbitan fatty acid ester, and an ink ribbon was manufactured using the ink. I attached this to the printer and started printing. As a result of similar evaluation, as shown in Figure 2 d, the PC was printed approximately 17 million times.
5 value was 0.3, indicating the life of the ink ribbon.

In addition, the wear depth after 100 million printing operations is 7n, the tip shape does not change macroscopically, and the print pixel quality is clear.
There was no deterioration in hue, and the ribbon ink had good fluidity.

Example 4 Variogen blank KO0845 parts, average particle size 5.0μ
The same procedure as in Example 3 was conducted except that 10 parts of graphite was used.

As shown in Figure 2e, the results of the evaluation show that the PC was printed 20 million times.
The 3 value was 0.3, indicating the life of the ink ribbon.

In addition, the wear depth after 100 million printing operations is 7-, the tip shape does not change macroscopically, the print pixel quality does not deteriorate in sharpness or two hues, and the fluidity of the ribbon ink is slightly lower. Although it has changed, there was no problem in using it.

Comparative Example 2 3 parts of Palogenburanoku KO08, average particle size 5.0-
A ribbon ink was produced in the same manner as in Example 3, except that 12 parts of graphite was used, but the ribbon ink had poor fluidity and could not be uniformly coated and impregnated onto the ink ribbon base fabric.

Based on the above results, the graphite 1 degree mentioned above is taken as the horizontal axis, and the number of printings at which the PC3 value becomes 0.3 is taken as the joint axis.
As shown in the figure. According to the figure, the life of the ink ribbon becomes longer as the graphite a degree increases, and in particular, it was found that the addition of 5 parts increased the life by about twice. When the number of copies reached 10, the life span reached about 2.5 times. Furthermore, if the amount exceeds 10 parts, the fluidity of the ribbon ink deteriorates, making it impossible to uniformly coat and impregnate the ink ribbon base fabric.

Also, regarding the average particle size, instead of the above 5.0- graphite, the average particle size is 1. Otna, 3. On, 7.
The same procedure was carried out using graphite (0 umO), but the results were almost the same.

Comparative Example 3 30 parts of vegetable oil, 30 parts of natural oil, pariogen blank KO
An ink ribbon was produced in the same manner as in Example 1, except that 08412 parts, oil-soluble dye 15 parts, Carbon Bra 7li 3 parts, and sorbitan fatty acid ester 10 parts were used, and the ink ribbon was attached to a printer and operated for printing. The evaluation result was that the PC3 value was 0.3 after about 12 million times of printing, which was the end of the life of the ink ribbon.

Furthermore, the wear depth in the axial direction reached 291 after 100 million printing operations. Although a slight change in the shape of the tip was observed as shown in FIG. 5, no unprinted pixels were observed.

Comparative Example 4 The same procedure as Comparative Example 3 was carried out except that 10 parts of Paliogen Black KO08 and 5 parts of carbon black were used.

As a result of the evaluation, the PC3 value was 0.3 after 16 million times of printing, indicating that the ink ribbon had reached its lifespan.

Further, the wear depth after 100 million printing operations reached 86-.

In addition, the shape of the tip became sharp as shown in FIG. 6, and the ink ribbon was damaged several times, and some of the ink ribbons got caught and broke.

Comparative Example 5 The same procedure as Comparative Example 3 was carried out, except that 00845 parts of pariogen black and 10 parts of carbon black were used.

The evaluation result was that the PC3 value was 0.3 after 19 million times of printing, which was the end of the ink ribbon's lifespan.

In addition, the wear depth after 100 million printing operations reaches 145n.
Furthermore, the tip became extremely sharp and the ink ribbon was damaged at several points.

In the above examples, the Variogen black has 008
In place of 4, other condensed polycyclic pigments and azo pigments.

Similar results were obtained using phthalocyanine pigments and organic pigments such as lake pigments.

〔Effect of the invention〕

As described in detail above, according to the present invention, by mixing 5 to 10 parts by weight of graphite in a concentrated portion in ribbon ink using an organic pigment, a high-speed printing head using the above-mentioned iron-based printing wire can be realized. It significantly reduces the wear of printing wires in impact printers, and also significantly improves the printing 4 degree characteristic in the near-infrared region, drastically reducing reading errors in OCR devices used for human power of information to computers, etc., and ensuring stable human power. It is possible. In addition, it is possible to extend the life of the ink ribbon, which is an excellent effect.

It goes without saying that the same effect can be obtained not only in the above-mentioned impact printer but also in other type printers such as female type printers.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the relationship between the amount of graphite mixed and the number of printings, FIG. 2 is a diagram showing the relationship between the number of printings and the PO2 value, and FIGS. 3 to 6 are schematic diagrams of the shape of the end of the printing wire. 1.2...Tip of printing wire. Graphite 5 content and tpτ times 1 length Fig. 1 Fig. 3

Claims (1)

[Claims] In an ink ribbon consisting of a ribbon base material and an ink containing an organic pigment as a coloring material, the ink has an ink 100
An ink ribbon containing 5.0 to 10.0 parts by weight of graphite.