JPH01249354A - Ink jet type recording apparatus - Google Patents

Abstract

PURPOSE:To secure the strength of a film in the running direction thereof and to prevent the contamination of a recording medium, by specifying the width of the second region having no small hole formed thereto positioned at the edge part of the first region having a small hole formed thereto in the width direction thereof. CONSTITUTION:For example, the gap between a recording surface 5 and a film 7 is set to 0.5mm being a proper gap at the time of the recording of a character as a dot pattern. Since the width dimension (d) of the second region 21 having small holes or recessed parts formed thereto of the film 7 is set to 0.08mm or more, the strength of the film 7 can be secured and the cutting of the film 7 during recording can be suppressed and the use life thereof can be enhanced. Since the width dimension (d) of the second dimension is set to below 3mm, the liquid droplet of the ink 13 sticked to the hole free region 27 of the film 7 is absorbed by the small holes 9 before the height thereof becomes 0.5mm and the ink 13 is not brought into contact with the recording surface 5 and the contamination of the recording surface 5 can be suppressed by a simple constitution without using other cleaning means.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to, for example, an inkjet recording device,
In particular, it applies to a thermal inkjet recording apparatus in which ink supplied to small holes in a film is heated by a thermal head and then jetted onto a recording medium.

(Prior Art) Methods for printing and recording characters on recording media such as paper are classified into impact methods and non-impact methods. A recording device employing this non-impact method has advantages such as being less noisy and smaller in size than a recording device using an impact method.

As such a non-impact recording device, there is a thermal inkjet recording device.

Compared to conventional devices that eject ink particles from nozzles to form dot patterns on the recording medium, which tend to clog the nozzles, thermal inkjet recording devices do not use nozzles, so they can prevent clogging. Can be done.

A thermal inkjet recording device has, for example, a structure in which an ink supply means supplies ink to a large number of small holes formed in a film, heats the film with a thermal head, and jets C ink particles onto the recording surface of a recording medium. There is.

FIG. 3 shows a plan view of the film.

Ink is supplied to the film 101 in the area surrounded by ABCD in the figure, and the small holes are regularly formed in the first small hole forming area 103 shown by the diagonal line in the figure in the area surrounded by ABCD. ing. In the area surrounded by this abcd, both edges in the width direction of the film 101 have no holes formed therein. It is 105.

Then, an ink supply means (not shown) uniformly supplies ink to the small hole forming area 103 and the hole-free lft 105 of the film 101. The ink supplied to the pore-forming region 103 is filled into the pores by capillary action, and the ink supplied to the pore-free region 105 remains as droplets on the film 101. Among these, the ink droplets existing at the critical point between the pore-forming region 103 and the poreless area Vi 105 are absorbed into the pores by capillary action, but the ink droplets present in the poreless head 14105 coalesce. There is a risk that it will turn into human-sized droplets.

On the other hand, in the above-mentioned inkjet recording Rib, it is necessary to set the gap between the film 101 and the recording medium to an optimal value depending on the dot image in order to stabilize the jetting direction of ink particles. For example, when recording characters on a recording medium, it is desirable that the gap is Q, 5 mm or less.

On the other hand, in the conventional apparatus, since the width dimension of the non-perforated area 105 of the 10 films is not taken into account, if this width dimension is set large, as shown in FIG. 4, for example, the ink 10
There is a possibility that the height of the droplet No. 7 exceeds the gap between the film 101 and the recording medium 109 (for example, see FIG. 4(a)).

In this case, as shown in FIG. 4(b), there is a problem that the ink 107 comes into contact with the recording medium 109 and contaminates the recording surface (see FIG. 4(C)). In addition, in the same figure, 111 is a t-normal head.

On the other hand, for example, as shown in Figure 5, Kong Mu-ryo-ryo was established (
) It is possible to use a film 110 that has not been prepared. In the figure, the small holes are arranged in a zigzag pattern with, for example, a pitch of 1100 u or less on the negative side, and the liquid layer of ink is absorbed into the small holes by the size of the ink that exceeds the gap, resulting in contamination of the recording surface. can be suppressed.

However, if no perforation areas are set on both edges of the film 110, the strength of the film 110 in the running direction will be reduced, and there is a risk that the film 110 may be cut during recording.

It is also conceivable to add a separate cleaning means to remove ink from the non-hole area, but this increases the number of parts and makes layout design difficult.

<Problems to be Solved by the Invention> As mentioned above, in the conventional apparatus, the width dimension of the hole-free area provided at both edges of the film is not particularly considered.
If it is set to a large value, there is a risk that the recording surface of the recording medium may be contaminated, while if it is set to a small value, there is a problem that the strength of the film itself in the running direction is reduced.

The present invention has been made in view of the above-mentioned problems, and aims to provide an inkjet recording device that can prevent contamination of a recording medium with a simple configuration while ensuring strength in the running direction of the film. purpose.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, the present invention provides a recording medium that is movable in close proximity to the recording surface of the recording medium and has a large number of small holes or recesses. A formed film, an ink supply means for supplying ink to the small holes or recesses of the film, and a thermal head for heating the film supplied with ink by the ink supply means and jetting the ink onto the recording surface. An inkjet recording device comprising: a first region in which a small hole or a recess is formed in the middle part in the width direction; and a first region in which a small hole or a recess is formed in the widthwise edge; and a second region not formed from the outer layer, and the width dimension of the second region is set to be 0.08 mm or more and less than 3 mm.

Further, when recording characters on the recording surface of the recording medium, the width dimension of the second area is o, o8mm or more, and Q,3
It was configured to be set to less than mm.

(Function) In the above configuration, in order to record a desired dot pattern on the recording surface of the recording medium, ink is supplied to the running film by the ink supply means.

At this time, the ink supplied to the first region is absorbed into the small hole or recess by capillary development, and the same phenomenon occurs because the width of the ink supplied to the second region is set to be less than 3 mm. Absorbed into pores or recesses.

Thereafter, the film is heated by a thermal head and ink is jetted onto the recording surface to obtain a desired dot pattern.

Since the width dimension of the second region of the film is not less than o, osmm, sufficient strength in the running direction of the film is ensured.

(Example) Hereinafter, an example of the present invention will be described in detail based on the drawings.

FIGS. 1 and 2 show an inkjet recording apparatus according to an embodiment of the present invention.

In FIG. 1, an inkjet recording apparatus 1 has a film 7 placed close to a recording surface 5 of a recording medium 3 such as paper. The film 7 is manufactured by, for example, an etching method or an electroforming method, and is used in a serial recording type printer or the like. In this embodiment, for example, the gap between the recording surface 5 and the film 7 is set to 0.5 mm, which is an appropriate gap for recording characters as a dot pattern.

The film can run as indicated by the arrow in the figure by a running i structure (not shown). The film has many small holes 9 of several tens of micrometers in diameter, for example, 25 micrometers.
m (for example, 25 μl 11) pitch.

An ink supply rod 11 that contacts the surface of the film 7 facing the recording surface 5 is disposed at the rear of the film 7 in the running direction. The ink supply rod 11 is configured to fill the small holes 9 of the film 7 with ink 13.

The film 7 has film mounting portions 15.degree. 17 at the front and rear portions with respect to the running direction, for example, as shown in FIG. Ink 13 is not supplied to the film mounting portion 15.17, and it does not come close to the recording medium 3. film 7
The area where the ink 13 is supplied by the back ink supply rod 11 and comes close to the recording medium 3 is the area surrounded by ABCD in the figure, similar to the conventional example.

The small hole 9 is formed in a small hole forming region 19 as a first region shown by diagonal lines in the figure out of the region shown by ABCD. In the area surrounded by ABCD, both edges in the width direction of the film 7 are a second area with no holes 1421 in which the small holes 9 are not formed.

The width dimension d of each hole-free area 21 is, for example, 038 mI.
Il is set to C. In other words, when a droplet of ink 13 adheres to the hole-free VX 21, the contact angle is 90' or less, so in order to prevent the ink 13 from contacting the recording surface 3, the height of the droplet must be 0. It is necessary to absorb it into the small holes 9 before it reaches 5fflIll. Therefore, if the width dimension d of the hole-free area 21 is set to less than 1 mm, the ink 1
A droplet of 3 is absorbed into the small hole 9, but in this embodiment, it is set to 0°8IIlll in consideration of safety. Further, it has been found through experiments that if the width d of the non-perforated area 21 is set to about 0.8IIll, sufficient strength in the running direction of the film 7 can be ensured.

A thermal head 23 is disposed in front of the film 7 in the running direction, and is in contact with the surface of the film 7 that faces the recording surface 5 . On the contact surface of the thermal head 23 with the film 7, a large number of heating elements (not shown) are provided at predetermined pitches in the width direction of the film 7.

The ink supply rod 11 and the thermal head 23 are
For example, movement is controlled in the same direction as the running direction of the film 7 at a speed that is approximately the same as or slower than the running speed of the film 7.

In the above configuration, each small hole 9 of the film 7 is filled with ink 13 using the ink supply rod 11, and the ink 13 is heated by the thermal head 23 for 7JI+ to form bubbles, and the ink particles formed by this bubble formation are It is injected to collide with the recording surface 5. At this time, by biasing the back of the heating element of the thermal head 23 corresponding to the desired dot image toward the film 7 side, only the ink 13 filled in the small hole 9 passing over the biased heating element is applied. is recording surface 5
It is possible to form a dot pattern by resisting collisions.
At this time, a small hole 9 is placed on the back side where the height of the droplet of the ink 13 attached to the holeless region 1421 of the film 7 does not reach Q, 5 mm.
Since the ink 13 is absorbed by the ink, it is possible to prevent the ink 13 from coming into contact with the recording surface 5 and contaminating the recording surface 5 with a simple structure without using any other cleaning means.

The thermal head 23 used in this recording apparatus operates in the same manner as a normal head in a known thermal transfer type recording apparatus, and the film 7 corresponds to the ink ribbon in the same recording apparatus.

In this embodiment, the gap between the recording surface 5 and the film 7 was set to Q, 5 mm, but it was set to an appropriate gap when recording a square dot pattern (for example, image tIA), and the hole-free area of the film 7 was The width dimension d of 21 may be changed according to this suitable gap. In this case, for example, the appropriate gap is 1.5 mm.
and the width d of the holeless area 21 is 3. It has been found through experiments that similar effects can be obtained even when the thickness is set to less than Qmm. Furthermore, it was found that the strength of the film 7 could be ensured by setting the dimensions to be equal to or greater than o, osmm.

Furthermore, it goes without saying that a recess may be formed in the film 7 instead of the small hole 9. In this case, for example, it is conceivable that the film 7 has a three-layer structure, in which through-holes are formed in the first layer and an ink supply section communicating with the through-holes is formed in the second layer.

[Effects of the Invention] As explained above, according to the present invention, the width dimension of the second region of the film in which the small holes or recesses are not formed is 0.
．． By setting the length to 0.81 m or more, the strength of the film can be ensured, and the film can be prevented from being cut during recording, thereby improving its service life. In addition, since the width dimension of the second area is set to less than 3n+n+, the ink does not remain in the second area and form large droplets, which prevents contamination due to contact with the recording surface of the recording medium, making it stable. can be recorded.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of an ink jet recording apparatus according to an embodiment of the present invention, FIG. 2 is a plan view of the film shown in FIG. 1, FIG. 3 is a plan view of a conventional film, and FIG. FIG. 3 is an explanatory view of the operation, and FIG. 5 is a plan view of a film according to another conventional example. 3...Recording medium 5...Recording surface 7...Film 9...Small hole 11...Ink supply rod (ink supply means) 13...
One ink...small pore formation area iii! (First area) 21...
・No-hole area (second area) 23... Thermal head d... Width dimension

Claims (2)

[Claims] (1) A film that is movable in close proximity to the recording surface of a recording medium and has a large number of small holes or recesses formed therein, an ink supply means that supplies ink to the small holes or recesses of this film, and this ink. The inkjet recording apparatus includes a thermal head for heating a film supplied with ink by a supplying means and ejecting the ink onto the recording surface, the film being located in the middle part in the width direction and having a small It has a first region in which holes or recesses are formed and a second region located at the edge in the width direction and in which no small holes or recesses are formed, and the width dimension of this second region is 0.08 mm. An inkjet recording device characterized in that the thickness is set to above and less than 3 mm. (2) When recording characters on the recording surface of the recording medium, the width dimension of the second area is 0.08 mm or more and 0.8 mm.
The inkjet recording apparatus according to claim 1, wherein the inkjet recording apparatus is set to less than mm.