JPH0692001A - Ink ribbon - Google Patents

Abstract

PURPOSE:To produce an ink ribbon with durability which can achieve good printing quality even when the impact force of a dot wire of a dot impact printer is small. CONSTITUTION:This is an ink ribbon for a dot impact, printer, having the ink impregnated in a base cloth. The base cloth is a fabric of 25-35 denier yarns in 82-100mum thickness. When the yarn of the base cloth is 30 denier, the total number of yarns in the longitundinal and lateral directions is 300-330per one square inches.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink ribbon for a dot impact printer (hereinafter simply referred to as "dot printer").

[0002]

2. Description of the Related Art Ink ribbons for dot printers are
It is usually a woven fabric such as 6,6-nylon impregnated with ink. As the base fabric for the ribbon, a plain fabric of 40 denier (d) yarns consisting of 34 filaments (F), 170 plains per inch and 117 horizontals, or 212 verticals per inch A high-density cloth, which is plain-woven with 124 horizontal pieces, is usually used. The thickness of these base fabrics is about 110 μm for general fabrics and about 125 μm for high-density fabrics when measured with a constant pressure micrometer. Ordinary ink impregnated into the base cloth contains synthetic oil, a dispersion medium such as oleic acid and a solvent of about 75 to 80% by weight, a dye such as solvent black, and a pigment such as graphite or carbon black. It was added.

For these ink ribbons, ribbons of general cloth may be used for printers with low impact and low noise. In that case, it is mainly used for a 9-pin printer because there is concern about the durability of the base cloth. In addition, a high-density cloth ribbon is almost used for a general 24-pin printer. On the other hand, when printing with multi-copy paper, it is said that the dot wire of the printer head needs a kinetic energy of about 5 mJ / dot in consideration of the copyability of the lower layer paper, and also the print noise level. Is about 50 to 55 dB.

[0004]

When printing on multi-copy paper using a conventional ink ribbon, there is a problem that the kinetic energy required for the dot wire is large and the printing noise is high. It is an object of the present invention to obtain an ink ribbon having good durability and good print quality even if the impact force of the dot wire is small.

[0005]

The ink ribbon for a dot printer obtained by impregnating a base cloth of the present invention with an ink is a woven cloth composed of 25 to 35 denier yarn and has a thickness of 82 to 100 μm. It is characterized by using. Further, when a woven fabric made of 30 denier yarn which is usually easily available is used, it is preferable that the woven fabric has a total number of longitudinal and transverse threads of 300 to 330 per square inch.

A woven fabric made of 6,6-nylon is suitable as the above-mentioned base fabric. 4 for commercially available 6,6-nylon fabrics
There are, for example, plain weaves of 0d / 34F or 30d / 26F yarns, but the base fabric according to the present invention is the latter or a property close thereto. The ink may be a normal dye ink or a dye / pigment ink containing graphite or carbon black. However, the one containing graphite has the effect of reducing the wear of the dot wire, but the black density of the print is lowered, so the amount is set to the minimum necessary amount. Further, the ink containing carbon black has a high black density for printing, but if the content of carbon black exceeds 5% by weight, the dot wire and the base cloth will be rapidly worn, so it is preferable to set it to 5% by weight or less.

[0007]

[Function] The properties required for the base fabric of the ribbon are that it holds ink well, transfers the ink to the paper properly when it is rubbed by the head dot wire, and attenuates the impact force of the dot wire as much as possible. It can be transmitted to the paper without being made, and has durability against repeated printing, and has rigidity (stiffness) so that it does not bend while the ribbon is running. In general, since a ribbon having a thin base cloth has less attenuation of impact force, energy required for the head can be reduced and printing noise can be reduced, but the ribbon becomes weak. On the other hand, a thick ribbon has to be strong, but the impact force of the dot wire must be increased, resulting in higher noise.

The conventional base cloth for the ink ribbon made of 40d yarn has a large thickness and requires a high printing pressure. On the other hand, the base fabric made of the thread of 30d has a small thickness, and a high print density can be obtained even with a low impact force. In this case, if the total number of yarns per square inch of the base fabric is less than 300, it is not preferable because the stiffness of the ribbon becomes too weak and the ribbon is easily bent during running. As the total number of threads per square inch of the base fabric increases, the thickness of the ribbon and the weight per unit area increase almost in proportion. In order to obtain a predetermined print density, a high impact force is required in proportion to the ribbon thickness.
When the total number of yarns in the length and width per square inch is more than 330, the result is almost similar to that of the conventional base fabric. Therefore, the total number of threads in the length and width per square inch of the base fabric is
In the case of 30d yarn, it is preferable to make 300 to 330 yarns. The relationship between the total number of vertical and horizontal threads per square inch and the thickness of the base cloth of the base cloth with 30d threads is 82 μm when the number is about 300 and 100 μm when the number is 330.
Is.

On the other hand, a ribbon having a relatively thin thread of the base cloth has poorer durability in printing than a thick ribbon having a large thickness. Therefore, when carbon black is included in the ink with which the ribbon is impregnated, it is preferably 5% by weight or less. 5
When the content is more than 10% by weight, the ribbon is wavy due to repeated printing, the base fabric is damaged, and running irregularities are likely to occur, which is not preferable. By using the ink ribbon base fabric having the above-described specific specifications, good printing quality can be obtained with a small impact force, and durability is also good.

[0010]

EXAMPLES The present invention will be described below by way of examples in comparison with conventional examples. [Example 1] Conventional base cloth woven with 6,6-nylon 40d / 34F yarn in plain weave and 6,6-nylon 30d / 2
A base cloth woven with a 6F thread was prepared. As shown in Table 1, the respective base fabrics differ in the number of vertical and horizontal yarns per inch, the former being two types and the latter being five types. Table 1 shows the thickness of the base fabric and the weight per 1 m ² measured with a constant pressure micrometer. Each base cloth was impregnated with a predetermined amount of the same dye ink as the conventional one, and both ends of a ribbon having a length of 8 m were joined to form an endless piece, which was housed in a cartridge to prepare a sample.
The composition of the ink is 5% by weight of Solvent Black 3 (trade name of black dye / pigment ink, Oil Black HB
B, manufactured by Orient Chemical Co., Ltd., 15% Solvent Black 7 (trade name of black dye ink, Oil Black B)
Y, manufactured by Orient Chemical Co., Ltd.), 40% oleic acid and 40% α-olefin synthetic oil.

Next, each sample was set in a dot printer, the kinetic energy of the dot wire was adjusted to 5 mJ / dot, and continuous printing was carried out using 4-copy paper. For each sample, the runnability of the ribbon, the clarity of printing, and the pressure-sensitive density of the second to fourth sheets of copy paper were examined. The pressure-sensitive density of cyan was measured with a Macbeth densitometer RD914 type (trade name, manufactured by Macbeth Co.). In addition, 4 when printed with sample number 2
The energy (mJ / dot) of the dot wire that gives a density equivalent to the pressure-sensitive density of the first sheet was examined for each sample. Table 1 shows the results of these tests.

[0012]

[Table 1]

The main items of the results shown in Table 1 are shown in FIGS. 1 to 5. The numbers attached to the white circles and black circles showing the data in the figure are the sample numbers. FIG. 1 is a graph showing the relationship between the number of threads per square inch and the thickness of the base fabric.
The 40d base fabric has a thickness of 110 μm or more, while 3
It can be seen that the base fabric of 0d is thinner than that. Further, as the number of threads increases, the thickness increases, and there is a correlation between the number of threads and the thickness.

FIG. 2 is a graph showing the relationship between the number of threads and the pressure-sensitive print density of the third copy of the 4-copy paper. In the case of 40d, the density is at a low level, and the density does not change much even if the number of yarns increases. All of 30d have higher density than the former. When the number of threads increases, the density tends to decrease, and when the number of threads is about 335, it becomes 4
The number of threads is 33 because it is close to the value of the ribbon of 0d.
It can be seen that 0 or less is preferable. On the other hand, when the number of yarns is small, the density is high, but in sample No. 3, since the ribbon is broken as shown in Table 1 and the durability is poor, it is understood that the number of yarns is preferably about 300 or more.

FIG. 3 is a graph showing the relationship between the thickness of the ribbon instead of the number of threads in FIG. 2 and the pressure-sensitive printing density of the third sheet. From the figure, it can be seen that the pressure-sensitive print density is inversely related to the ribbon thickness.

FIG. 4 is a graph showing the relationship between the number of threads and the required energy of the dot wire. The 40d type has a high level of required energy and does not change much even if the number of yarns increases. The 30d type has lower energy requirement than the former type. The required energy tends to increase as the number of yarns increases, and approaches the value of the ribbon of 40d. Therefore, it is understood that the number of threads is preferably 330 or less. On the other hand, when the number of yarns is small, the required energy is low, but considering the breakage of the ribbon as described above, the number of yarns is preferably about 300 or more.

FIG. 5 is a graph showing the relationship between the thickness of the ribbon and the required energy of the dot wire instead of the number of threads in FIG. It can be seen that the required energy has a positive correlation with the thickness of the ribbon.

Considering the above results comprehensively, FIG. 6 shows a range in which the object of the present invention can be suitably achieved. That is, the inside of the rectangle surrounded by the alternate long and short dash line is the portion that satisfies the requirements of the present invention. The base fabric of the ink ribbon of the present invention needs to be woven to have a thickness of 82 to 100 μm using 25d to 35d yarns. For example, 3 which is relatively easy to obtain
When using 0d yarn, the total number of length and width per square inch is 300 to 330 and 82 to 100 μm.
Thickness. Also, as shown by interpolating with the chain double-dashed line, when using a slightly thicker thread, for example, a thread of 35d, the total number of threads in the length and width is adjusted so that the thickness of the base cloth falls within the range of the rectangle. Should be set.

[Example 2] Thickness 9 used in sample No. 5
A 0 μm base cloth was impregnated with four types of ink having different compositions of carbon black having the compositions shown in Table 2. The ink composition in the table is% by weight.

[0020]

[Table 2]

Next, for each sample, as in Example 1, 300
After printing 10,000 characters, the damaged state of the base cloth and the presence or absence of abnormal running of the ribbon were observed. The results were similar to the results of Example 1 up to a carbon black content of 5%,
When the content of carbon black was 10%, there was no running abnormality, but the ribbon was broken, and the ribbon wavy phenomenon occurred. When the carbon black content is 15%, damage to the base cloth occurs before reaching 3 million characters.
Abnormal running of the ribbon was recognized.

[0022]

As described above, the ink ribbon of the present invention is one in which the thickness of the base cloth is optimized by specifying the specifications of the threads constituting the base cloth and the density of the threads of the woven cloth. It is possible to achieve good printing with a small printing power, to reduce noise of the head during printing, and to extend the life of the ribbon.

[Brief description of drawings]

FIG. 1 is a graph showing the relationship between the number of threads per square inch of a base fabric of an ink ribbon and the thickness of the base fabric.

FIG. 2 is a graph showing the relationship between the number of threads of the base cloth and the pressure-sensitive printing density of the third sheet of 4-copy paper.

FIG. 3 is a graph showing the relationship between the thickness of the base cloth and the pressure-sensitive printing density of the third sheet.

FIG. 4 is a graph showing the relationship between the number of threads of the base cloth and the required energy of the dot wire.

FIG. 5 is a graph showing the relationship between the thickness of the base cloth and the required energy of the dot wire.

FIG. 6 is a graph showing a preferred range of the present invention for an ink ribbon base fabric.

Claims (2)

[Claims] 1. An ink ribbon for a dot impact printer comprising a base cloth impregnated with ink, wherein the base cloth is 2
An ink ribbon, which is a woven fabric composed of 5 to 35 denier yarn and has a thickness of 82 to 100 μm. 2. The base fabric is formed by weaving a yarn having a denier of 30 to a thickness of 82 to 100 μm by using a total of 300 to 330 lengths and widths per square inch. 1. An ink ribbon for a dot impact printer according to 1.