JPS60192672A - Ink-impregnated platen for printer - Google Patents

Abstract

PURPOSE:To obtain an ink-impregnated porous body having favorable printing property and durability, by a method wherein a sintered nylon body having a capillary suction pressure varied at a negative gradient from the printing surface side toward the side of a fitting surface for fitting to a platen substrate is impregnated with an ink. CONSTITUTION:In an ink-impregnated platen type printer, an ink-impregnated platen obtained by fitting an ink-impregnated porous body to a platen substrate to form a printing surface is faced to a printing head through a printing paper. In the printer, the ink-impregnated porous body is produced by a method wherein a sintered nylon body having a capillary suction pressure varied at a negative gradient from the printing surface side toward the side of a fitting surface for fitting to the platen substrate is impregnated with an ink. Namely, since the capillary suction pressure of the sintered body for the ink is determined by the size and the number of pores and is increased with a decrease in the pore diameter and an increase in the number of the pores, the sintered nylon body is produced in consideration of these points. Accordingly, an ink-impregnated platen can be obtained which can smoothly supply an ink to the printing surface, can maintain a favorable printed condition for a long period of time and has excellent printing property, high surface strength and excellent durability while sufficiently enduring the impact of a printing wire.

Description

Detailed Description of the Invention (Objective) The present invention relates to a printer, and more particularly to an ink-impregnated platen type printer using a platen whose printing surface is formed of an ink-impregnated porous material. to provide superior ink-impregnated platens.

(Prior Art) Printers currently used for data communication terminal devices, computer output devices, etc. print paper by selectively hitting a platen with character forming elements such as type or wire through an ink ribbon and printing paper. So-called ink ribbon type impact printers that print on paper are widely used.

In particular, dot-impact printers that use wire as character forming elements are small and can produce many characters, symbols, and
It is widely used as a printer that can print figures etc. in orange.

However, ink ribbon type printers require the installation of an ink ribbon cassette and the running of the ribbon, making the 848 complicated. In particular, in order to meet the demand for multicolor printing that has come with the diversification of recent printer usage, multiple ribbon cassettes and print heads are required. This makes the mechanism even more complicated.

In response to this, an ink-impregnated platen type printer as shown in FIG. 1 was developed as a dot impact type printer that can easily perform multicolor printing with a simple mechanism.

A printing surface is formed by attaching a plurality of ink-impregnated porous bodies 5 impregnated with ink of each color to the outer peripheral surface of the print head 1 having wires 2 as character forming elements through a printing paper 3. The device is equipped with an ink-impregnated platen 4, and printing is performed by rotating the ink-impregnating platen 4 appropriately, selecting the printed surface binding-C of the ink-containing porous body 5 of a predetermined color, and hitting the printed surface with the wire 2. This is a printer that prints on paper 3 in a predetermined color.

As an example, the ink-impregnated platen 4 in the printer has a magnet 9 fitted in a groove 8' provided in the mounting surface 8 of the platen base 7, as shown in FIG. It is advantageous if an iron plate 6 is attached to the ink-impregnated porous body 5 and the ink-impregnated porous body 5 is detachably attached to the platen base 7 so that the ink-impregnated porous body 5 can be easily replaced.

In the above-mentioned ink-impregnated platen printer,
When the surface of the ink-impregnated porous material is struck by a wire through the printing paper, the ink that oozes out onto the surface of the ink-impregnated porous material is transferred to the printing paper, and printing ends at the printing point. Immediately after that, ink is replenished by the ink-impregnated porous body against the ink by a capillary suction phenomenon or a pumping action based on minute elastic deformation, and the ink is prepared for the next printing.

Therefore, in order to maintain good printing quality over a long period of time, the ink-impregnated porous material must not only have excellent strength to withstand the impact of the printing wire, but also have the above-mentioned ink oozing and replenishing functions performed smoothly. That is necessary.

Conventionally, a sintered nylon body mainly made of nylon 66 resin powder has been used as a porous body for ink impregnation as a porous body with appropriate elasticity and strength. In order to reduce variations in durability, powder with fixed properties (viscosity, manufacturing, etc.) is filled into a mold and compacted with uniform pressing force, resulting in a homogeneous state in which the diameter and number of pores are uniformly distributed. In other words, it was formed to have a uniform density, and this density was about 0.80±0.01.

When a nylon sintered body with a uniform density as described above is impregnated with ink and used as an ink-impregnated platen for printing, the printing is performed at a preferable density at the initial stage of printing, and the deformation of the printing surface due to wire printing causes the surface to change. It is in good condition with no unevenness.

However, printing 4: As the number of printers increases, it becomes difficult to replenish ink to the printing surface smoothly, resulting in a decrease in printing 'aa' and significant unevenness on the printing surface, making it difficult to obtain good printing quality. Therefore, the life of the ink-impregnated platen was extremely short.

Conventionally, attempts have been made to measure the problems of printability and durability as described above by increasing or decreasing the density, but as the density increases, the durability improves, but the printability decreases and the printability deteriorates. If the density is decreased, the print density will increase, but the ink will transfer to the printing paper a lot, making it difficult to print clearly and at the same time reducing the durability.

The present invention was devised in view of the above-mentioned current situation and as a result of intensive studies to obtain an ink-impregnated porous material with good printability and durability.

(Structure) That is, the present invention provides an ink-impregnated platen type printer in which an ink-impregnated platen, in which an ink-impregnated porous body is attached to a platen base to form a printing surface, is arranged facing a print head via printing paper. The ink-impregnated porous body is characterized in that it is formed by impregnating ink into a sintered nylon body that has a capillary suction force for ink with a negative gradient from the printing surface side to the mounting surface side with respect to the platen base. An ink-impregnated platen for a printer, as described in more detail below based on an example.

The capillary suction force for ink in a sintered body is determined by the size and number of pores, and decreasing the pore diameter and increasing the number of pores will increase this. A nylon sintered body was formed.

Example 1 One-layer, one-time single-press method Nylon 66 resin powder with a particle size of 10 to 150 μm was filled into a mold, and pressed from one side at room temperature with a pressure of about 800 Kg/arm2 to form a green compact. The compact was taken out of the mold and sintered in a nitrogen stream at 260° C. for 60 minutes in a non-oxidizing atmosphere according to a conventional method.

FIG. 3 shows a side sectional view of the obtained sintered body, and this sintered body is compacted by pressing force in the direction of the arrow and is obtained as a rectangular parallelepiped with a density distribution as shown by the numbers in the figure. This was machined with the high-density side as the printing surface A and the low-density stone side as the mounting surface B to form a predetermined shape as shown by the solid line.

FIG. 4 is a cross-sectional view of the sintered body taken along the line C-C, showing how the ink is sucked up by the capillary suction force when the obtained sintered body is immersed in ink. 11 is ink.

As is clear from FIG. 4, in this embodiment, the capillary suction force for the ink on the printing surface A side is strong and the ink suction height is high; There is.

Example 2 Two-layer, two-time pressing method A nylon resin powder consisting of 10% by weight of nylon 6 resin and 90.1nffi% of nylon 66 resin with a particle size of 10 to 150 μm was used as a raw material and compacted as shown in FIG. 5.

In Fig. 5, 12 is a die, 13 is an upper punch, 14 is a lower punch, and 15 is a die fixing block.
Fill the raw material powder 16 into the cavity as shown in >.
Subsequently, as shown in Figure (B), the first powder molded material layer 17 is formed by pressing at room temperature with the upper punch 13 at a pressure of about 1100 Kg/cm2, and then as shown in Figure (C). After filling the raw material powder 16 again onto the first powder compact layer, it is punched with the upper punch 13 for 60 minutes at room temperature as shown in FIG. 1(d).
A second powder compact layer 18 was formed by applying a pressure of about 0 kg/cIm2.

Next, the powder compact formed by the two-layer, two-time pressing method was taken out of the mold and sintered at 260°C for 60 minutes in a nitrogen stream. Average density 0.
The weight of the rectangular parallelepiped sintered body is 1q.

Subsequently, the sintered body was machined into a predetermined shape by closing the first layer side to the printing surface side, but the capillary suction force of this sintered body to the ink was stronger on the printing surface side as in the first embodiment. The mounting surface was weak.

In this embodiment, powder compacting is performed using a single-pressing method, but powder compacting may be performed using a double-pressing method.

Example 3 Two-layer, one-time, double-pressing method (Using powders with different compression ratios) Two types of powders with different compression ratios, consisting of 10% by weight of nylon 6 resin and 90!4ffi% of nylon 66 resin with particle sizes of 10 to 150μ Powders obtained by the chemical pulverization method and powders obtained by the amizing method were prepared, and these were used as raw material powders and compacted as shown in FIG. 6.

In this embodiment, the die 12 is the same as that of the embodiment 2 in order to use the double-pressing method.
The first raw material powder 19 prepared as shown in FIG. 6(a) is first filled into the cavity, and then as shown in FIG. 6(b).
After moving the die 12 upward as shown in FIG.
As shown in C), two layers 21 with different densities based on the difference in compressibility are formed by pressing from both the upper and lower directions with a pressure of about 900 Kg/Cl112 by an upper punch 13 and a lower punch 14 at room temperature.
．． A powder compact consisting of No. 22 is obtained.

Next, in the same manner as in the other embodiments, the compact was taken out of the mold and sintered according to a conventional method, and a layer of chemically pulverized powder was added.
1 average density 0.85, average of 22 layers of atomized powder!
A rectangular parallelepiped sintered body with l1m0.75 was obtained and machined into a predetermined shape with the chemically pulverized powder layer side as the printing surface side.

The capillary suction force of the sintered body of this example was strong on the printing surface side and weak on the mounting surface side, as in the first and second examples.

Example 4 Two-layer, one-time, double-pressing method (using powder with particle diameter) Different particle sizes of 10 to 43μ and 44 to 150μ, consisting of 10% by weight of nylon 6 resin and 90% by weight of nylon 66 resin Two types of powders were prepared and used as raw material powders, which were compacted and sintered in the same manner as in the third example.
0~43μ side, 0°83, particle size 44~150μ side 0.8
A straight sintered body having an average density of 6 was obtained.

Next, in the same manner as in the other examples, the sintered body formed of the two layers was machined into a predetermined shape with the grain size side of 10 to 43 μm as the printing surface side.

The capillary suction force of the sintered body of this example was also strong on the printing surface side and weak on the mounting surface side.

Example 5 Burnishing Finishing Method Nylon 66 resin with a particle size of 10 to 150μ was used as a raw powder, and both upper and lower punches were used to uniformly press the powder to form a green compact, which was then sintered to obtain a sintered body with a density of 0.80. .

Subsequently, after machining the sintered body into a predetermined shape, the seventh
As shown in the figure, a burnishing tool 24 was pressed against the printed surface of the sintered body 23 mounted on a jig (not shown) to finish the printed surface with burnishing of 5 to 30 μm, and the printed surface density was 0.90 or more.

In the sintered body of this example, the capillary suction force was strong on the printing surface side and weak on the mounting surface side, as in the other examples.

In the case of two-layer molding in Example 2.3.4, nylon 6 resin IJFt was blended into the raw material powder, but this was because the melting point (220°C) of nylon 6 resin was the same as the melting point of nylon 66 resin. This is because it has the effect of increasing the sintering force and preventing separation between layers, which is much lower than that of nylon 6'
Nylon 610, a low melting point nylon resin, instead of resin
．． 612.11.12 etc. can have the same effect.
Rukoto can.

Furthermore, in the case of molding with two layers as in the embodiment, it is naturally possible to mold with three or more layers.

A printing test was conducted using the nylon sintered body prepared in Example 1 as an ink-impregnated platen of a printer, and each example showed good results in both printability and durability. .

Even though the sintered body of the present invention has a high density printing surface, the capillary suction force is strong, so an appropriate amount of ink oozes out onto the printing surface, making it possible to print extremely clearly. Since the ink was replenished to the surface very smoothly, a good printing condition was maintained over a long period of time.Furthermore, since the printing surface was formed with high density, it was strong and exhibited excellent durability.

Furthermore, it is clear from Example 4 that the method of increasing the capillary suction force for ink in the sintered body is not to increase the density of the sintered body (to decrease the pore diameter and increase the number of pores).

Therefore, the method of forming a sintered body with a higher capillary suction force for ink on the printing side of the present invention is to make the pore diameter on the printing side smaller and increase the number of holes, and such a sintered body Some examples of how to form the same are given below.

(Effects) As described above, according to the present invention, ink is smoothly replenished to the printing surface, good printing condition is maintained for a long period of time, and the printing quality is superior, and the surface strength is high.
An ink-impregnated platen is provided that exhibits excellent durability and withstands a 1" pounding.

Therefore, this makes it possible to provide a printer that is simple in 4R construction, can easily perform multicolor printing, and has excellent printing performance and durability, and this effect is extremely large.

[Brief explanation of the drawing]

Figure 1 is a perspective view showing an overview of an ink-impregnated platen type printer, Figure 2 is a perspective view showing an ink-impregnated platen, and Figure 3 is a perspective view showing an ink-impregnated platen.
7 to 7 are diagrams showing embodiments of the present invention. 1...Print head, 2...Print wire 17.3...
Printing paper, 4... Ink-impregnated platen, 5... Ink-impregnated porous body, 7... Platen base.

Claims (1)

[Claims] In an ink-impregnated platen type printer in which an ink-impregnated platen, in which an ink-impregnated porous body is attached to a platen base to form a printing surface, is arranged facing a print head via printing paper, the ink-impregnated porous body is An ink-impregnated platen for a printer, characterized in that the platen is impregnated with ink in a nylon sintered body having a capillary suction force against the ink with a negative gradient from the printing surface side toward the mounting surface to the platen base.