JP2503049B2 - Ink ribbon - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an ink ribbon.

(Prior Art) Impact printers, which have the advantage of cost advantages in recent years and are capable of high-speed printing on various media, are used as a man-machine interface for various applications including peripheral terminal devices of information processing systems. It is used, and the demand for high-speed printing is particularly high. In an impact printer that prints at high speed, high reliability of the print head is one of the important issues in order to stably process a large amount of information. In particular, it is strongly desired that the printing wire operates stably for a long period of time without causing abrasion or damage to the ink ribbon. For example, there is a printing wire using a wear-resistant alloy such as cemented carbide, or an iron-based printing wire which is inexpensive and easy to process (JP-A-59-79766).

On the other hand, regarding the high-speed operation of the print head,
As shown in 4-2PP9, etc., weight reduction of the movable part including the print wire is one of the important factors. But,
Since the above-mentioned cemented carbide printing wire contains approximately 70-85% by weight of tungsten carbide, its density is 13.5%.
It is as heavy as ~ 14.5 g / cm ^3, and it is difficult to reduce the weight of the printing wire.

Therefore, in order to realize high-speed printing, it is unavoidable to use a light weight general iron-based printing wire with the density of about 8 g / cm ^3, but the iron-based printing wire has a large abrasion property and the life of the print head is long. There was a defect that reliability was poor such as shortening.

By the way, the above-mentioned print wire wear is mechanical abrasive wear by the ink ribbon.

The black ink of the conventional ink ribbon is, for example, Japanese Patent Publication Sho 57
-60956 contains carbon black as a coloring material, that is, adding carbon black and an oil-soluble dye as a coloring material to vehicle oil, which is a vehicle, and mineral oil, and further adding an auxiliary agent such as a dispersant. It is the composition.

Then, the carbon black mechanically wears the surface layer of the printing surface of the printing wire by the same action as the fine particles of the abrasive powder, causing so-called abrasive wear.

(Problems to be Solved by the Invention) There is also a ribbon ink using an organic pigment instead of carbon black in order to avoid such abrasive wear. However, the print density of the ribbon ink print sample is lower than that of the ribbon ink print sample using carbon black, because the print density for wavelength light in the near infrared region (wavelength 780 to 1500 nm) is lower than that of the ribbon ink print sample. There was a problem that occurred. That is, the life of the ink ribbon is naturally shortened, the increase of the ribbon length for compensating for this increases the cost, and there is a drawback that the printer becomes large in size because the ribbon cartridge of the printer becomes large.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an ink ribbon which eliminates the above-mentioned disadvantage that the print density in the near infrared region is reduced.

(Means for Solving the Problem) The present invention provides an ink ribbon comprising a ribbon base material and a ribbon ink using an organic pigment, wherein
It contains 5.0 to 10 parts by weight of graphite.

(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 the organic pigment, and exhibits the wear-reducing effect and the suppressing effect of the above-mentioned print density decrease due to the lubricating effect. It is a thing.

(Example) Hereinafter, an example of the present invention will be shown and specifically described. Parts in the following description are parts by weight.

Comparative Example 1 30 parts of vegetable oil and 30 parts of mineral oil as vehicles as shown in the table below.
Parts, 15 parts of a condensed polycyclic organic pigment (Paraogen Black K0084, manufactured by BASF) and 15 parts of an oil-soluble dye as a coloring material, and 10 parts of a sorbitan fatty acid ester as a dispersant are premixed with a planetary mixer, and this mixture is prepared. Was uniformly kneaded with three rolls to prepare a ribbon ink. As the ink ribbon base fabric, nylon 6 or nylon 66
Polyester fiber or polyester fiber such as 50m in length, 13mm in width and 0.12mm in thickness was used as Mobius's ring-shaped endless ribbon base fabric, and 12g of the above ribbon ink was uniformly applied and impregnated per one of them. . The obtained ink ribbon was attached to an impact printer together with a print head using an iron-based print wire, and printing was started. Operating conditions are printing stress of 14 kg / mm ² , printing speed of 180 times / sec, ink ribbon feed rate of 30 mm / sec, and replace the ink ribbon with a new one every 20 million times of printing per printing wire. Ink consumption was kept constant.

With regard to the print density of the print sample, the dependence of the print density on the print number was examined as the print density (PCS value) for every 2 million prints made by printing one ink ribbon with the print wire. The printing density is Macbeth PC
PCS with B filter using M-II type densitometer
Indicated by value. PCS value 1.0 is pure black, 0.0 is pure white,
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 is the life of the ink ribbon.

As a result, as shown in Fig. 2a, PCS was printed with about 8 million prints.
The value was 0.3, indicating the life of the ink ribbon.

Next, regarding the wear of the printing wire, as shown in FIG. 3, the length reduction Δh on the central axis of the printing wires 1 and 2 before and after the evaluation was measured in micron units (hereinafter, this Δh is Also called axial wear depth). Further, the change in the tip shape of the printing wire was observed using an electron microscope. As a result, the wear depth in the axial direction of the printing wire that had been operated for printing 100 million times was 7 μm, and the tip shape did not change macroscopically as shown in FIG.

Example 1 30 parts vegetable oil, 30 parts mineral oil, paliogen black K0084
An ink was obtained by mixing 12 parts, 15 parts of an oil-soluble dye, 3 parts of graphite having an average particle size of 5.0 μm and 10 parts of sorbitan fatty acid ester to obtain an ink, and using this, an ink ribbon was manufactured. This was mounted on a printer and printing was performed, and the same evaluation as in Comparative Example 1 was performed. As a result, FIG. 2b
As shown in, the PCS value was 0.3 after printing 12 million times, and the life of the ink ribbon was reached.

In addition, the wear depth after 100 million printing operations is 8 μm,
The tip shape did not change macroscopically, and no deprinted pixels were confirmed.

Example 2 30 parts vegetable oil, 30 parts mineral oil, paliogen black K0084
An ink ribbon was produced by mixing 10 parts, 15 parts of an oil-soluble dye, 5 parts of graphite having an average particle size of 5.0 μm, and 10 parts of sorbitan fatty acid ester to obtain an ink. This was mounted on a printer and printing was performed. As a result of the same evaluation as in Example 1, as shown in FIG. 2c, the PCS value was 0.3 after printing about 15 million times, and the life of the ink ribbon was reached.

In addition, the wear depth after 100 million printing operations is 8 μm,
The tip shape did not change macroscopically, and the print pixel quality did not deteriorate in its sharpness and hue. Furthermore, there was no change in the fluidity of the ribbon ink.

Example 3 30 parts vegetable oil, 30 parts mineral oil, paliogen black K0084
An ink ribbon was produced by mixing 8 parts, 15 parts of an oil-soluble dye, 7 parts of graphite having an average particle size of 5.0 μm, and 10 parts of sorbitan fatty acid ester to obtain an ink. This was mounted on a printer and printing was performed. Second result of similar evaluation
As shown in Figure d, the PCS value was 0.3 after printing about 17 million times, and the life of the ink ribbon was reached.

The abrasion depth after 100 million printing operations was 7 μm, the tip shape did not change macroscopically, the print pixel quality did not deteriorate in its sharpness and hue, and the fluidity of the ribbon ink was good. It was

Example 4 The same procedure as in Example 3 was carried out except that 5 parts of Paliogen Black K0084 and 10 parts of graphite having an average particle size of 5.0 μm were used.

As a result of the evaluation, as shown in FIG. 2e, the PCS value became 0.3 after printing 20 million times, and the life of the ink ribbon was reached.

The wear depth after 100 million printing operations is 7 μm, the tip shape does not change macroscopically, the print pixel quality does not deteriorate in its sharpness and hue, and the fluidity of the ribbon ink changes slightly. However, there was no problem in use.

Comparative Example 2 A ribbon ink was produced in the same manner as in Example 3 except that 3 parts of Paliogen Black K0084 and 12 parts of graphite having an average particle size of 5.0 μm were used, but the fluidity of the ribbon ink was poor.
The ink ribbon base cloth could not be applied and impregnated uniformly.

Based on the above results, the aforesaid graphite density is plotted on the abscissa and the number of prints at which the PCS value is 0.3 is plotted on the ordinate. According to the figure, it was found that the life of the ink ribbon was prolonged with the increase of the graphite concentration, and especially the life was extended about twice by adding 5 parts. The life reached about 2.5 times as much as 10 parts. Further, when the amount is 10 parts or more, the fluidity of the ribbon ink deteriorates, and the ink ribbon base fabric cannot be evenly applied and impregnated.

Regarding the average particle size, the same operation was carried out by using graphite having an average particle size of 1.0 μm, 3.0 μm, 7.0 μm instead of the above graphite having an average particle size of 5.0 μm, but the results were almost the same.

Comparative Example 3 30 parts vegetable oil, 30 parts mineral oil, paliogen black K0084
An ink ribbon was manufactured in the same manner as in Example 1 except that 12 parts, 15 parts of oil-soluble dye, 3 parts of carbon black, and 10 parts of sorbitan fatty acid ester were used, and printing was performed by mounting the ink ribbon. The evaluation result showed that the PCS value was 0.3 after printing 12 million times, and the life of the ink ribbon was reached.

Also, the axial wear depth after 100 million printing operations is 29 μm.
Has reached. The tip shape slightly changed as shown in FIG. 5, but no unprinted pixels were confirmed.

Comparative Example 4 Paliogen Black K0084 10 parts, Carbon Black 5
The same procedure as in Comparative Example 3 was performed except for the parts. The evaluation result showed that the PCS value was 0.3 after printing 16 million times, and the life of the ink ribbon was reached.

Further, the wear depth after 100 million printing operations reached 86 μm. The shape of the tip became sharp as shown in FIG. 6, the ink ribbon was damaged several times, and several of them were broken by hooking the ink ribbon.

Comparative Example 5 Paliogen Black K0084 5 parts, Carbon Black 10
The same procedure as in Comparative Example 3 was performed except for the parts. The evaluation result showed that the PCS value was 0.3 after printing 19 million times, and the life of the ink ribbon was reached.

Further, the wear depth after 100 million printing operations reached 145 μm, the tip shape became remarkably sharp, and the ink ribbon was damaged several times.

In the above examples, the above Paliogen Black K0084
Similar results were obtained when other condensed polycyclic pigments, azo pigments, phthalocyanine pigments, dyed lake pigments, and other organic pigments were used instead.

[Effects of the Invention] As described above in detail, according to the present invention, the iron-based printing wire described above is used by mixing the ribbon ink using the organic pigment with 5 to 10 parts by weight of graphite. Mark wire wear of impact printer with high-speed print head is significantly reduced, print density characteristics in the near-infrared region are significantly improved, and reading error of OCR device used for inputting information to computer etc. is drastically reduced and stable. It is possible to make various inputs. In addition, the service life of the ink ribbon can be extended, and an excellent effect is exhibited.

It is needless to say that the present invention can obtain the same effect in other printers such as a mother-type type printer in addition to the above impact printer.

[Brief description of drawings]

FIG. 1 is a diagram showing the relationship between the amount of graphite mixed and the number of prints, FIG. 2 is a diagram showing the relationship between the number of prints and the PCS value, and FIGS. 3 to 6 are schematic diagrams of the end portions of the print wires. 1,2 ...... Print wire tip.

Claims (1)

(57) [Claims] 1. An ink ribbon comprising a ribbon substrate and an ink containing an organic pigment as a coloring material, wherein the ink contains 5.0 to 10.0 parts by weight of graphite based on 100 parts by weight of the ink. ribbon.