JPH0472695B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a method for removing melt from a thermal stencil maker.

BACKGROUND TECHNOLOGY In general, this type of thermal stencil making machine, as shown in FIG. It is used for plate making. In this case, the base paper 1 is
Since the stencil is made while pressing the base paper against the surface of the head 2, the molten base paper 4 sticks to the vicinity of the heating element 2a, increases as the number of stencils is made, and covers the heating element 2a as shown in FIG. Otherwise, the adhesion between the heating element 2a and the heat-shrinkable film 1b deteriorates, as shown in FIG. For this reason, the heat of the heating element 2a becomes difficult to be transmitted to the heat shrinkable film 1b, resulting in occurrence of white spots on the surface image.

As a means for removing such molten material 4, there is a method in which the user wipes the surface of the heating element 2a of the thermal head 2 with a cloth soaked in alcohol or the like. In this method, the work itself is complicated and difficult. Furthermore, although melted matter that has simply adhered to the surface of the heating element 2a can be removed, it is difficult to remove that which has adhered.

There is also a method of passing cleaning paper or the like between the head 2 and the platen roller 3 in the same way as the base paper. In the case of this method, it is difficult to completely remove the molten material that has adhered to the heating element 2a, and furthermore, it is almost impossible to remove the molten material that has adhered or adhered to a portion away from the heating element 2a. It is. In cases where such cleaning is required frequently, if the base paper 1 is not in sheet form but in roll form, cleaning is difficult and troublesome unless the roll paper is removed from the set state. There is.

Purpose The present invention has been made in view of the above points, and provides a thermal stencil plate making machine that can easily and reliably prevent melted base paper from adhering to or sticking to the vicinity of the heating element, and can eliminate image omissions, etc. The purpose is to obtain.

Structure The present invention provides a thermal stencil making machine in which a heat-sensitive stencil sheet is passed between a heat-generating head such as a thermal head and a platen roller, and the heat-sensitive stencil paper is perforated by a heat-generating element of the heat-generating head. At least a piece of paper such as Japanese paper with a rough surface and not dense fibers is pasted on a part of the non-image area on the surface side with a width wider than the effective plate-making image width, and this paper passes through the position of the heat generating element of the heat generating head. At times, the heating element generates heat. Therefore, the molten material stuck on the heating element is melted by the heat generated by the heating element and scraped off by the paper, thereby being reliably removed. Furthermore, by increasing the pressing force of the platen roller, the platen pressure can be applied to the melt adhering to areas other than the knit width of the platen roller, thereby making it possible to reliably remove it.

Embodiment A first embodiment of the present invention will be described based on FIGS. 2 and 3. In this example, a sheet-shaped base paper 1
This is applied to the case where the heating element 2a
Place it on the contact surface side, that is, in front of the non-image area other than the image area indicated by the dashed line A on the heat-shrinkable film 1b, and use paper whose width is wider than the image area, whose fibers are not dense, and whose surface is rough. , for example, Japanese paper 5 is glued.

According to such a configuration, the image portion A of each base paper 1
Before plate making, Japanese paper 5 is passed over the surface of the heating element 2a of the thermal head 2 in contact with the base paper 1. In other words, the Japanese paper 5 passes while rubbing the surface of the heating element 2a.At this time, since the fibers of the Japanese paper 5 are not dense and the surface is rough, the melted base paper that has adhered or adhered to the surface of the heating element 2a is rubbed on the surface of the heating element 2a. It is scraped off and removed in a state where it gets entangled between the fibers.

Therefore, according to this embodiment, the melted material from the base paper can be removed just by performing the normal plate-making process, and since it is done after each plate-making process, the adhesion or sticking of the melted material can be prevented. It turns out. As a result, there is no need for the user to wipe the surface of the heat generating element with a cloth or to pass a cleaning paper through it, as in the past, making the removal simple and highly effective.

By the way, in order to further enhance the removal effect, it is effective to cause the heating element 2a to generate heat while the Japanese paper 5 is passing over the heating element 2a. Due to this heat generation, the melted base paper that had adhered to the heating element 2a is melted again and becomes soft, and in this state it is scraped off with the Japanese paper 5, so that removal becomes more reliable.

Next, a second embodiment of the present invention will be described with reference to FIG. Generally, the platen roller 3 presses the base paper 1 against the heating element 2a at a constant pressure P, and during the plate-making process, the melted base paper 4 is transferred to a portion near the heating element 2a, as shown in FIG. The platen roller 3 is deformed and becomes attached or fixed to the outside of the portion (nip) in contact with the thermal head 2. Therefore, in this state, Japanese paper 5
Although it is possible to remove the molten material 4 from the vicinity of the heating element 2a by passing through the nip, it is difficult to remove the molten material adhering to the outside of the nip width W because no pressure is applied thereto. In this regard, in this embodiment, as shown in Figure b, the pressing force of the platen roller 3 is set to P + ΔP when passing the Japanese paper 5, which is larger than that during plate making, and the nip width is increased to W + ΔW. a
During plate making, platen pressure is applied even to the melt 4 adhering outside the nip width W, as shown in FIG. As a result, if Japanese paper 5 passes,
The melted material 4 adhering outside the nip width W can also be reliably removed.

Next, a third embodiment of the present invention will be described with reference to FIG. Generally, when the platen roller 3 has both the function of pressing the base paper 1 onto the heating element 2a and the function of feeding and driving the base paper 1 at a constant speed, the platen roller 3 usually has a surface layer made of a soft elastic material. often made. For this reason, during plate making, the platen roller 3 is deformed toward the lag side in the rotational direction as shown by the solid line (the dashed line indicates a perfect circle), as shown in FIG. 5a, and the nip width is Wa, Wb become Wa<Wb,
The melt 4 will adhere to the outside of the nip width W. Even if the Japanese paper 5 is passed in this state, it will not be as effective as the case shown in FIG. 4a. Therefore, in this embodiment, while the Japanese paper 5 is once held between the platen roller 3 and the head 2, the platen roller 3 is similarly rotated in the reverse direction as shown in b. As a result, the deformation of the platen roller 3 is reversed as shown in the figure, the nip width becomes Wa>Wb, and the platen pressure is applied to the melt 4 that was located outside the nip width W during plate making in figure a. It becomes like this. Therefore, this molten material 4 is scraped off by the Japanese paper 5. This embodiment is particularly effective when the surface layer hardness of the platen roller 3 is small and the platen pressure is large.

It is of course possible to combine the heat generation of the heating element 2a, the increase in pressure of the platen roller 3, and the reverse rotation of the platen roller 3 shown in these embodiments when passing five Japanese papers. Further, in FIG. 2, the Japanese paper 5 is provided in the non-image area on the front side of the base paper 1, but it may be provided in the non-image area on the rear side and removed after plate making.

6a to 6c show the mounting position of the Japanese paper 5 in the case of a roll-shaped base paper 1 wound around a roll core 6. FIG. Figure a shows the case where Japanese paper 5 is adhered to the leading edge of base paper 1. Figure b shows the case where Japanese paper 5 is glued to the rearmost end of the roll of base paper 1. And c in the same figure is 1
Glue Japanese paper 5 to the non-image area for each length l of the printing plate, and
This is shown in which the melt is removed every time the plate is made (that is, the base paper 1 is in a continuous state as shown in FIG. 2).

Effects As described above, the present invention provides a thermal stencil making machine in which a thermal stencil sheet is passed between a heat generating head such as a thermal head and a platen roller, and the thermal stencil sheet is perforated by a heating element of the heating head. Paper such as Japanese paper with a rough surface and not dense fibers is pasted to a part of the non-image area on the contact surface of the heating head, and the paper has a width wider than the effective plate-making image width, and this paper is used to cover the heating element of the heating head. Since the heating element is made to generate heat when passing the position,
The molten material stuck on the heating element is melted by the heat generated by the heating element and scraped off by the paper, making it possible to reliably remove it.In addition, by increasing the pressing force of the platen roller, the nip width of the platen roller can be reduced. The platen pressure is also applied to the melted material that has adhered to other objects, so that it can be reliably removed.

[Brief explanation of the drawing]

1A and 1B are side views showing a conventional example, FIG. 2 is a perspective view showing a first embodiment of the present invention, FIG. 3 is a longitudinal side view showing an enlarged part of the base paper, and FIG. Figures 4a and 4b are side views showing the second embodiment of the present invention, Figures 5a and b are side views showing the third embodiment of the present invention, and Figures 6a to c are side views of the rolled base paper. FIG. 1... Base paper, 2... Thermal head (heating head), 2a... Heat generating element, 3... Platen roller,
5...Japanese paper (paper).

Claims (1)

[Scope of Claims] 1. In a heat-sensitive stencil making machine in which a heat-sensitive stencil paper is passed between a heat-generating head such as a thermal head and a platen roller and the heat-sensitive stencil paper is perforated by a heat-generating element of the heat-generating head, the heat-sensitive stencil paper is Paste paper such as Japanese paper with coarse fibers and a rough surface to a part of the non-image area on the contact surface side at least in a width wider than the effective plate-making image width, and this paper passes through the position of the heat generating element of the heat generating head. 1. A method for removing molten material from a heat-sensitive stencil plate-making machine, characterized in that the heating element generates heat when the stencil is removed. 2. Claim 1, characterized in that when the paper passes the position of the heating element of the heating head, the pressing force by the platen roller is increased.
A method for removing molten material from a heat-sensitive stencil-making machine as described in 2.