JPS63290766A - Recording head for electrothermal transfer recorder - Google Patents

Abstract

PURPOSE:To obtain a recording head capable of maintaining stable printed image quality for a long time, by using an insulating resin as a material for a head substrate, chamfering the tip of the substrate in the range from the front edge of a surface for contact with a recording head to the back surface of the substrate, and providing a tip surface of the back surface with a notched groove parallel to electrode needles. CONSTITUTION:A head substrate 2 is an insulating substrate comprising a polyimide resin as a main constituent, and only the back surface of a tip part of the substrate is provided with a notched groove 4 in a width of 0.8 mm. Rib parts 5 of 0.2 mm width are provided at both sides of the groove 4, and each of the rib parts 5 is provided with a chamfer 6 by 45 deg. chamfering. The chamfer 6 is provided ranging from the vicinity of and end edge of a contact surface 7 for a recording film 13, which is provided at a tip part of the substrate. A heat-resistant insulating layer 8 comprising a polyimide resin is provided on the upper surface of the substrate 2, and a plurality of electrode needles 3 comprising tungsten as a main constituent are provided thereon, with an electrode width of about 50 mum and a pitch of 106 mum. Therefore, adhesion or deposition of printing refuse on the tip of a recording head can be reduced, printed image quality can be prevented from being lowered, and the useful life of the head can be further prolonged.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to an improvement in a recording head of an electric transfer recording apparatus.

Conventional technology> An electric transfer recording device applies electricity to a resistive layer of a recording film using an electrode needle of a recording head, and the heat generated by the resistive layer melts the ink on the recording film and transfers it to recording paper. The figure shows the state of the tip of a conventional recording head.

In the figure, 10 is a recording head having a large number of electrode needles 12 arranged on the surface of an insulating head substrate 11, 13 is a recording film consisting of an ink layer, a conductive layer, and a resistive layer, 14 is recording paper, and 15 is a platen. The recording head 10 is brought into pressure contact with the recording film 13 and is energized while sliding, so that the ink in the ink layer is melted by the heat generated by the resistive layer and transferred onto the recording paper 14.

As the recording head 10 slides on the resistive layer of the recording film 13, part of the resistive layer peels off due to friction or heat generated by energization, resulting in scraps of the peeled resistive layer (hereinafter referred to as printing scraps). ) adheres to the tip jIs of the recording head 10, and as printing operations are repeated, print residue gradually accumulates, causing deterioration of print image quality. In addition, the tip of the recording head IO is worn out by sliding with the recording film 13, and the distance A (
(hereinafter referred to as the amount of retreat) increases, and as this increases, the pressure on the contact surface with the recording film 13 decreases, making the contact unstable and adversely affecting ink transferability, which also deteriorates the print image quality. Cause.

<Problems to be Solved by the Invention> Conventionally, there is a structure in which the head substrate 11 of the recording head 10 is made of ceramic and a plurality of electrode needles 12 are arranged on the surface thereof. In this case, the amount of adhesion and accumulation of printing residue is relatively large, and the amount of abrasion due to sliding is small. Therefore, the printing residue is hardly removed by the sliding abrasion against the recording film during printing, and the print image quality deteriorates. It occurred in a relatively short period of time. For this reason,
The head is lapped with an abrasive sheet as needed to remove deposits from the tip of the head in order to restore the print quality. However, such treatment is very time-consuming and inconvenient for the user, and causes high usage costs.In addition, from a manufacturing perspective, processes such as forming electrode needle patterns on ceramics and firing are required. The cost is high.

In addition, in the case of a structure in which resin is used for the head base @11,
Since the amount of wear due to sliding is large and the amount of retraction increases quickly, the amount of adhesion and accumulation of print residue is relatively small in the initial stage (deterioration of print image quality is unlikely to occur, but the amount of retraction increases and transferability deteriorates) Because the period between
In addition, as the amount of retraction increases, the contact pressure decreases due to the increase in the contact area with the recording film, which worsens the discharge of print residue and increases adhesion and deposits, resulting in a noticeable decline in print image quality. there were.

The present invention has been made in view of these problems, and aims to provide a recording head for an electrical transfer recording device that can maintain stable print quality over a long period of time at a low cost.

Means for Solving the Problems> In order to achieve the above object, the recording head of the current transfer recording apparatus of the present invention uses an insulating resin as the material of the head substrate constituting the main body of the recording head, The head substrate is chamfered from near the edge of the contact surface with the recording film to the back surface, and cut grooves parallel to the electrode needles are formed in at least the tip portion of the back surface of the head substrate.

Effect> Since insulating resin is used as the material for the head substrate, the amount of wear due to sliding is greater than that of ceramics, so there is less adhesion and accumulation of print scum, which reduces the quality of the print image. ni (i.

In addition, since a notch groove is formed on the back surface of the head substrate, the contact area with the recording film does not increase as much as when there is no notch groove when it wears out, and the pressure decreases less during pressing, resulting in improved print image quality. In addition, since the amount of retraction is constant in the notch light groove portion, there is no deterioration of ink transfer performance due to an increase in the amount of retraction. Since it is chamfered and has a pointed shape, there is little increase in the amount of retreat or increase in contact area due to wear due to this part, and deterioration of print image quality and ink transfer performance is also prevented.

<Example> Next, the illustrated embodiment will be described.

In FIGS. 1 and 2, 1 is an insulating head substrate 2.
This is a recording head in which a large number of electrode needles 3 are arranged on the surface of the recording head.

The head substrate 2 is an insulating substrate mainly made of polyimide resin with a thickness of about 1 [ugly], and only on the back side of the tip, a notch groove 4 is formed with a width of 0.8 [ugly] on both sides. Set the lip part 5 to 0.
2 [theory] width, and the lip portion 5 is chamfered at 45° to remove the portion indicated by the broken line to form the chamfered portion 6. This chamfered portion 6 is formed near the edge of the contact surface 7 with the recording film 13 formed at the end.

A heat-resistant insulating layer 8 made of polyimide resin with a thickness of 50 [μm1 is provided on the upper surface of the head substrate 2, and a plurality of electrode needles 3 whose main component is tungsten are placed on the heat-resistant insulating layer 8 with an electrode width of about 50 [μm].
-], pitch 106 [μm1], pitch 106 [μm1].

The recording head of this embodiment has the structure described above, and the results of a printing test using this will be described below. The test conditions are
Platen 15 sandwiching recording paper 14 and recording film 13
was pressed at an angle of 25° and printing was performed at a speed of 3600 [DPS].

First, the results of a printing test using a polyimide resin substrate without chamfering or groove processing and a 7 orstellite substrate as the head substrate 2 are shown. ml, the print image quality began to deteriorate due to the adhesion of printing residue, whereas on the resin substrate, almost no deterioration in the print image quality was observed even after printing about 6 kIIll of recording film. In addition, the amount of wear on the head tip RA is as follows: recording film 400 [1
], it was 7t lusterite substrate 2.97103 [l1l-31] and resin substrate 2,1/102 [logic-3] per head pressure contact part 1 [cm]. In other words, since the amount of wear on resin substrate recording heads is about 10 times greater than that on ceramic substrates, the tip of the head is constantly being polished, making it extremely difficult to prevent the adhesion and accumulation of print scum. It turns out that it is effective.

Next, a polyimide resin substrate was used as the head substrate 2, and the tips were not processed, those with only 45° chamfering, those with only groove processing, and those with 45° chamfering only.
The test results are shown for four types with both chamfering and groove processing.

First, in the case where the tip was not processed, the ink transfer performance deteriorated due to the increase in the amount of retreat after printing about 7 [kml] of the recording film. For the same amount of wear, the increase in the amount of regression is small, and the printing distance until deterioration of ink transfer performance occurs is about 1
It was 0[1ual. In addition, in the case where only groove processing is performed, the amount of recession in the groove does not increase beyond a certain length determined by the thickness t of the groove substrate (see Figure 1), so deterioration of ink transferability does not occur. As wear progresses, the area of the tip of the head that comes into contact with the recording film increases, and the adhesion and accumulation of printing debris increases, resulting in poor printing.
i! Quality is declining. The printing distance before this phenomenon occurred was approximately 13 kml.

Finally, for the product with both 45° chamfering and groove machining, the increase in the amount of recession is small for the same amount of wear (so the printing distance before the print quality deteriorates is about 20 km).
As a result, it was possible to print the longest distance among the four types of heads, and the effects of the chamfered portion 6 and the notched groove 4 were confirmed.

<Effects of the Invention> As is clear from the above embodiments, the recording head of the current transfer recording apparatus of the present invention uses an insulating resin as the material of the head substrate constituting the main body of the recording head, and the head substrate is made of an insulating resin. A chamfering process is applied from the vicinity of the edge of the contact surface with the recording film at the tip to the back surface, and notch grooves parallel to the electrode needles are formed on the back surface of the head substrate.

Therefore, there is less adhesion and accumulation of print residue on the tip of the recording head, and the print quality is less likely to deteriorate. ! By making full use of the characteristics of the oil substrate, maintenance work using polishing sheets etc. can be greatly reduced, and the notched grooves can prevent deterioration of ink transfer performance due to increased retreat, extending the life of the head. Furthermore, the chamfering process suppresses the increase in the amount of setback and the contact area, making it possible to further extend the life of the head. This allows the recording head to be provided at a lower cost.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of essential parts of an embodiment of the present invention, Ll!
The figure is a side view showing the printing state of the same embodiment, and Pt53 is a side view showing the printing state of the conventional example.

Claims (1)

[Claims] 1. The main body of the recording head is configured in an electrical transfer recording device in which a resistive layer of a recording film is energized by an electrode needle of the recording head, and the heat generated by the resistive layer melts the ink on the recording film and transfers it to the recording paper. An insulating resin is used as the material for the head substrate, and a chamfering process is applied from near the edge of the contact surface with the recording film at the tip of the head substrate to the back surface, and at least the tip portion of the back surface of the head substrate is chamfered parallel to the electrode needle. A recording head for an electrical transfer recording device, characterized in that a notch groove is formed.