JPH08282096A - Ink ribbon for impact printer - Google Patents

Abstract

PURPOSE: To provide an ink ribbon reducing the abrasion of a dot wire by printing even if a relatively inexpensive high speed steel wire is used, improving the OCR reading properties of printed matter, that is, reducing the difference between the visual density of the last stage of printing and reading accuracy by an OCR and enabling a user to visually and easily know a ribbon replacing period. CONSTITUTION: Fabric like base cloth is coated with black ink consisting of at least a coloring agent not containing carbon black or containing carbon black only in an amt. of 5% or less by wt. of the total amt. of the ink, an oils and fats component hardly volatilized at the normal temp., a dispersant and an org. near infrared absorber setting the difference between the PCS value of printed matter by visible light and the PCS value thereof by near infrared rays to 0.1 or less.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fabric ink ribbon for use in an impact printer, and particularly to a low abrasion ink ribbon for OCR in which there is little difference between the visual density of the printed matter and the machine reading accuracy. It is about.

[0002]

2. Description of the Related Art Conventionally, most ink ribbons used in impact printers are inks composed of a colorant, an oil component, and a dispersant applied to a fabric-like base cloth. Used a pigment system such as carbon black and an organic pigment, a dye system, and a dye-pigment system in which a pigment and a dye are mixed.

Among them, as proposed in JP-A-52-117200, an ink ribbon for OCR,
Especially for those that use near-infrared for the wavelength of the reading light,
Good near-infrared absorption and good OCR readability,
Those containing about 10% by weight of carbon black have been used. However, the ink containing carbon black has a large amount of wear of the dot wire, and especially the ink containing more than 5% by weight of the total amount of the ink causes the wear of the dot wire to extremely shorten the life of the printer head. It cannot be used for printer heads using HSS wire. If you use a special material such as tungsten carbide and a super steel wire made of an alloy such as cobalt or nickel, wear can be suppressed to some extent, but it becomes expensive and the ribbon is not versatile because it selects the printer head, Not preferable.

Ribbon inks for dot printers in which carbon black is not used or the amount of carbon black used is reduced and organic pigments such as aniline black are used as substitutes are disclosed in JP-A-63-170481 and JP-A-63-2.
It is proposed by Japanese Patent No. 75683. Also,
Dye-based ribbon inks for dot printers that do not contain pigments have been used from before. This type does not easily wear the dot wire due to printing, but it does not absorb near-infrared rays well and the printed matter is dark.
It is difficult to read with CR, and the density of the printed matter
It is not suitable as an ink for OCR because of a large difference from the reading accuracy by OCR.

Therefore, the object of the present invention is to reduce the wear of dot wires due to printing and to improve the OCR readability of printed matter, even if a relatively inexpensive high speed wire or the like is used. And OCR
The purpose of the present invention is to provide an ink ribbon for an impact printer, which has a small difference from the reading accuracy due to the above and allows the user to easily know the time of ribbon replacement by visual observation.

[0006]

Means for Solving the Problems In view of the above problems, the present inventor has conducted extensive studies and, as a result, applied an ink containing at least a colorant, an oil and fat component, and a dispersant to a fabric-like base cloth. In such an ink ribbon, it was found that the object of the present invention can be achieved by blending an organic near-infrared absorber in the ink, and the present invention has been completed based on this finding. That is, the present invention provides "1. A printed material comprising a colorant containing at least 5% by weight or less of carbon black with respect to the total amount of ink, an oil / fat component that is hardly volatile at room temperature, a dispersant, and an organic near-infrared absorber. PCS value in visible light and PC in near infrared light
A black ink ribbon obtained by applying a black ink having a difference from the S value of 0.1 or less to a fabric-like base cloth. 2. PCS in a visible light of a printed matter, which comprises at least a coloring agent which does not substantially contain carbon black, an oil and fat component which is hardly volatile at room temperature, a dispersant, and an organic near-infrared absorber.
An ink ribbon formed by applying an ink having a difference of 0.1 or less between the value and the PCS value in near infrared light to a fabric-like base cloth. 3. The ink ribbon for an impact printer according to any one of the items 1 and 2, wherein the organic near-infrared absorber dissolves in an oil and fat component that is hardly volatile at room temperature at 20 ° C. by 0.1% by weight or more. 4. Oleic acid is the first oil and fat component that is hardly volatile at room temperature.
An ink ribbon for an impact printer according to any one of items 1 to 3. 5. The ink ribbon for impact printers according to item 4, wherein the organic near-infrared absorber dissolves in oleic acid in an amount of 0.1% by weight or more at 20 ° C. 6. The organic near-infrared absorber has the maximum absorption peak in the wavelength range of light of 800 to 1000 nm.
An ink ribbon for an impact printer according to any one of items. 7. Organic near-infrared absorber is at least cyanine-based, phthalocyanine-based, naphthalocyanine-based, naphthoquinone-based, anthraquinone-based, aminium-based, dithiol metal complex salt-based, diimmonium-based, triphenylmethane-based, chronicmethine-based, azureniium-based, pyrylium-based The ink ribbon for an impact printer according to any one of items 1 or 6, which is selected. 8. The ink ribbon for an impact printer according to claim 1, wherein the organic near-infrared absorber is blended in an amount of 0.1 to 5.0% by weight. Is a feature.

Hereinafter, the present invention will be described in detail. As the colorant used in the present invention, carbon black, an inorganic pigment such as iron trioxide, cyanine blue, phthalocyanine blue, Victoria blue base, Hansa yellow, benzicin yellow, lake red, permanent carmine, perine red, aniline. Organic pigments such as black,
In addition, pigments containing oil-soluble dyes such as nigrosine base, methyl violet, oil blue and oil yellow are also included. A pigment and a dye may be used in combination, or a pigment system alone and a dye system alone may be mixed.
The colorant is preferably 5 to 30% by weight with respect to the total amount of the ink.

In the present invention, a near infrared absorber is incorporated as an essential component. When the coloring agent is a dye type and does not contain a near infrared ray absorbent, the printed matter looks good visually, but many of them cannot be read by OCR. There is a large difference between the OCR density and the OCR reading accuracy, and the OCR can be read at the beginning of printing, but due to the decrease in density due to use, it can be read visually on the way.
An error often occurs in R.

Since carbon black has an absorption wavelength in the near infrared region, it is preferable for OCR. However, as described above, since it accelerates the wear of the dot wire, it is preferably not used or 5% by weight or less is preferably used.
If it exceeds 5% by weight, abrasion is extremely advanced, which is not preferable. Only carbon black in an amount of 5% by weight or less is insufficient for OCR reading. Therefore, in the present invention, a near-infrared absorber is used together.

If the near infrared absorber is added in a relatively large amount, the present invention can be sufficiently achieved even in a system in which the coloring agent is a dye alone or an organic pigment system. However,
Since the near-infrared absorber itself is very expensive, it is necessary to reduce the amount thereof to be blended as much as possible. Therefore, 5% by weight or less of carbon black can be blended and used together. If the amount of carbon black is 5% by weight or less,
It does not significantly affect the wear of the dot wire. If you want to avoid the wear of the dot wire as much as possible, you can suppress the wear to the maximum without adding carbon black.

The density of the ink ribbon for impact printers gradually decreases as it is printed, but it can still be visually observed in a system containing no infrared absorber or carbon black, or a system containing a small amount of carbon black, but it can be read by OCR. It often happens that there is no. This is because the amount of light absorption in the visible light region is different from the amount of light absorption in the infrared light region of the OCR light source. In this case, the light absorption in the visible light region is greater than that in the infrared light region. This is because there is a difference in the absorption amount, which is larger than the absorption amount.

On the other hand, in a system containing a large amount of infrared absorbent and carbon black, the OCR may read the data even though the level is not visible. This is because, in this case, the absorption of light in the visible light region is smaller than the amount of light absorption in the infrared light region, and the above-described reverse absorption amount difference occurs.

Therefore, in the present invention, the difference between the PCS value of visible light and the PCS value of near-infrared light of the printed matter is set to 0.1 or less to eliminate the difference between visual observation and OCR reading. I was able to. As described above, there is a difference in reading regardless of which of the PCS value in visible light and the PCS value in near infrared light is large. Therefore, the difference must be 0.1 or less. In the present invention, the colorant and the infrared absorber are further used in combination, if necessary, in an amount of 5% by weight or less of carbon black, so that the difference between the PCS value in the visible light and the PCS value in the near infrared light of the printed matter is 0. It can be 1 or less. The infrared absorber is a cyanine type,
Phthalocyanine-based, naphthalocyanine-based, naphthoquinone-based anthraquinone-based, aminium-based dithiol metal complex salt-based, diimmonium-based, triphenylmethane-based, chronicmethine-based, azureniium-based, pyrylium-based, etc. There are no particular restrictions. The amount of the colorant added to the ink is preferably 5 to 30% by weight, and the amount of near infrared rays is preferably 0.1 to 5.0% by weight.

The oil / fat component used in the present invention is blended as a vehicle component of the ink, and the ribbon is used as an open type cassette ribbon which is in direct contact with the outside air. The oil / fat component used as the vehicle of the ink has especially 17 to 1 carbon atoms.
9 straight-chain fatty acids and / or their derivatives are preferred.
When the carbon number is smaller than this range, the volatility is increased, and when the carbon number is increased, the viscosity becomes too high, and it becomes solid depending on the temperature condition and is not suitable as a vehicle for the ink. As the linear fatty acid having 17 to 19 carbon atoms, oleic acid and stearic acid are preferably used, and oleic acid is most suitable. The blending amount is preferably 10.0 to 50.0% by weight.

The near-infrared absorbing agent is preferably one that dissolves in an oil and fat component that is hardly volatile at room temperature at 20 ° C., that is, 0.1% by weight or more in the vehicle used. This is because the near-infrared absorber, which is dissolved in the vehicle to some extent, has better absorption of infrared light, so that a small amount of the near-infrared absorber can be added. If it does not dissolve, it must be blended in a large amount, and it is expensive, so it is not preferable, and the effect will be reduced.

A dispersant is added in order to stabilize the dispersion of the colorant and the near-infrared absorber. Examples of the dispersant include nonionic surfactants such as fatty acid esters and polyoxyethylene alkyl ethers, and cationic surfactants such as alkylamine salts, and the compounding amount is preferably 5.0 to 50.0% by weight. .

In addition, additives such as surfactants and rust preventives can be appropriately added as required.

[0018]

The present invention will be described in more detail with reference to Examples and Comparative Examples. Example 1 Carbon black 3% by weight Aniline black 20% by weight Nigrosine dye 10% by weight Oleic acid 20% by weight Fatty acid ester 30% by weight Dispersant 15% by weight NIR-AM-1 (manufactured by Teikoku Chemical Industry Co., Ltd., aminium-based) Infrared absorber) 2% by weight The components of the above composition were mixed and dispersed to prepare a ribbon ink, and the ink was applied to a 6,6-nylon fabric base cloth to obtain a ribbon for impact printer.

Examples 2 to 4 and Comparative Examples 1 to 3 Inks having the compositions shown in Table 1 were prepared and applied in the same manner as in Example 1 to obtain ribbons for impact printers.

[0020]

[Table 1]

The seven types of ink ribbons produced in the above-mentioned Examples and Comparative Examples were printed with an impact printer M3361 manufactured by Fujitsu Ltd., and the abrasion amount of the dot impact wire at 100 million dots and 200 million dots was measured. The results are shown in Table 2.
It was shown to.

Further, after making seven kinds of ink ribbons into 10 m straight loops and printing with impact printer PC-PR201-CL manufactured by NEC Corporation, PCM-2 (filters A and D) manufactured by Macbeth. , Visible light (400-700 nm) and near infrared light (800-10)
The PCS value at 00 nm) is measured from the beginning of printing to the end of printing, and the point at which the PCS value in the near infrared light is 0.4, which is said to be generally difficult to read with an OCR device, is the printing end point. Table 2 shows the results of comparison between the printing life and the difference in PCS value between visible light and near-infrared light at the beginning and end of printing, that is, the end of printing.

[0023]

[Table 2]

The above examples were evaluated from the following viewpoints, and the results are shown in Table 2. The amount of wear of the dot impact wire was 200 million dots, and when the amount of wear was 100 μm or more, the printing quality was remarkably inferior, and therefore it was not usable. Also, the difference between the PCS value in visible light and the PCS value in near infrared light, especially when the PCS measurement value in near infrared light is 0.4
If the difference in S value is 0.1 or more, there is a problem that the OCR device cannot read it even if the printer user visually judges that it is still dark. When the above Examples and Comparative Examples are evaluated based on this judgment, all of Examples 1 to 4 can be used, but in Example 4, the infrared absorber used is almost insoluble in oleic acid. Therefore, compared with the first embodiment, the PC with visible light
The difference between the S value and the PCS value in the near infrared light is doubled, and the life is slightly shortened. The wear amount of the dot impact wire is within the limit in Comparative Example 1, but the difference between the PCS value in visible light and the PCS value in near infrared light is large. In Comparative Examples 2 and 3, the difference in PCS value is limited. However, a problem occurred because the amount of wear of the dot impact wire was too large.

The ink ribbon for impact printers of the present invention can be manufactured by using a relatively inexpensive high speed wire or the like.
There is little wear of the dot impact wire due to printing,
Moreover, it was possible to obtain an ink ribbon for an impact printer, in which the readability of the OCR of the printed matter was good from the beginning of printing to the end of printing.

Claims (8)

[Claims] 1. A printed material comprising a colorant containing at least 5% by weight or less of carbon black with respect to the total amount of ink, an oil-and-fat component that is hardly volatile at room temperature, a dispersant, and an organic near-infrared absorber. A black ink ribbon formed by applying a black ink having a difference between the PCS value and the PCS value in near infrared light of 0.1 or less to a fabric-like base cloth. 2. A PCS value in visible light of a printed matter and a near-infrared light, which comprises at least a coloring agent substantially free of carbon black, an oil and fat component which is hardly volatile at room temperature, a dispersant, and an organic near-infrared absorber. The difference from the PCS value at 0.
An ink ribbon made by applying an ink of 1 or less to a fabric-like base cloth. 3. The impact printer according to claim 1, wherein the organic near-infrared absorbing agent dissolves 0.1% by weight or more with respect to the oil and fat component which is hardly volatile at room temperature at 20 ° C. ink ribbon. 4. The ink ribbon for an impact printer according to claim 1, wherein the oil and fat component which is hardly volatile at room temperature is oleic acid. 5. The ink ribbon for an impact printer according to claim 4, wherein the organic near-infrared absorbing agent is soluble at 0.1% by weight or more in oleic acid at 20 ° C. 6. The organic near-infrared absorber is 800 to 100.
The ink ribbon for an impact printer according to any one of claims 1 to 5, which has a maximum absorption peak in a wavelength range of light of 0 nm. 7. The organic near-infrared absorber is at least a cyanine-based, phthalocyanine-based, naphthalocyanine-based, naphthoquinone-based, anthraquinone-based, aminium-based, dithiol metal complex salt-based, diimmonium-based, triphenylmethane-based, chronicmethine-based, azureniium. 7. An ink ribbon for an impact printer according to claim 1, wherein the ink ribbon is selected from the group consisting of a series and a pyrilium series. 8. An organic near-infrared absorber is added in an amount of 0.1 to 5.0.
The ink ribbon for an impact printer according to claim 1, wherein the ink ribbon is blended in a weight percentage.