JPS62116185A - Recording method - Google Patents

Abstract

PURPOSE:To form a clear recorded image of excellent quality on a recording medium at a low recording cost, by applying thermal perforation to a thermoplastic resin film while making the film and a dot-shaped heating element move slidably. CONSTITUTION:A thermoplastic resin film 1 such as a drawn polypropylene film is drawn out of a roll 2a and transferred continuously or intermittently in the direction of an arrow A. When a heat suitable for a desired picture pattern is impressed from a heating element 4a onto the film 1 while the film 1 moves slidable on the heating element 4a, the film 1 is thermally perforated uniformly in accordance with the aforesaid pattern. Since the resin film 1 slides on the heating element 4a, the melt 1c of the resin which is the material constituting the film 1 is pushed from a perforation 1b onto the surface of the film, at one end of the periphery of the perforation in the direction reverse relatively to that of running of said film, and it is accumulated and cured thereat in a prescribed shape. Ink 6a passes through a perforated portion 1a formed uniformly in the film 1, sticks on a recording medium 5 and forms a clear recorded image 8 having an excellent printing quality.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a recording method for forming a clear recorded image on a recording medium by using a uniformly heat-perforated thermoplastic resin film.

1. The thermal transfer recording method, which is widely used as a method for recording on indigo paper, generally involves dispersing a colorant in a heat-melting binder on a sheet-like support. A thermal transfer material coated with heat-melting ink is used to selectively melt the ink and transfer it to a recording medium, thereby forming a transferred recorded image on the recording medium according to the shape of heat supply. be.

However, in this heat-sensitive transfer recording method, a heat-sensitive transfer material is used, which is formed by forming a thin heat-melting ink layer of uniform thickness on a relatively expensive heat-resistant plastic film support; Since this thermal transfer material is disposable due to its wooden nature, the disadvantage is that the cost of thermal transfer recording is high, or that it is difficult to form a high-quality recorded image on a recording medium with poor surface smoothness. was there.

On the other hand, as a mimeograph recording method that makes it easy to obtain a large number of identical recorded images, a sheet made of thermoplastic resin film is brought into close contact with a printing device having dot-shaped heating elements, and the dot-shaped heating elements generate heat. A simple thermal dot perforation method is used, in which a base paper for stencil printing (II! Photoplate) is obtained by forming a perforation image on the film, and ink is passed through the perforation image area of the base paper to form a recorded image on the recording medium. A recording method has been proposed (Japanese Unexamined Patent Publication No. 54-33117).

This method has the characteristics that the recording cost is low, and since it is a mimeograph method, the print quality of the recorded image is not affected much by the smoothness of the surface of the recording medium. It is difficult to obtain clear and high quality recorded images by applying this method.

The main feature of the present invention is the heat perforation in the form of dots.
The present invention provides a recording method that can form clear and high-quality recorded images while taking advantage of the characteristics of the recording method using a plastic resin film.

The recording method of the present invention that achieves the above object is to bring a dot-shaped heating element into contact with one surface of a thermoplastic resin film, and cause the heating element to generate heat in a desired pattern to record the thermoplastic resin. Film on the door!・The step of thermally perforating the thermoplastic resin film in the shape of a recording medium, placing an ink supply member on the side of the film opposite to the recording medium contact surface, and causing ink to flow out from the ink supply member. The dot-shaped heating element is passed through the dot-shaped perforations of the thermoplastic resin film to form a recorded image on the recording medium. It is characterized by being able to move.

The recording method of the present invention has the above-described configuration, and the functions of this recording method will be described below in comparison with the prior art.

Generally, when thermally perforating a thermoplastic resin film using a dot-shaped heating element, there are two cases: multiple dots that are adjacent to each other in the vertical or horizontal direction generate heat, and cases where multiple dots that are not adjacent to each other generate heat. , the temperature at the outer periphery of each hole corresponding to each heating dot differs based on heat conduction. For this reason, the temperature distribution on the outer periphery becomes non-uniform along the outer periphery, and therefore the star of the melt of the thermal resin (constituent material of the film) adhering to the outer periphery of each hole also becomes non-uniform along the outer periphery. Become something.

In other words, at a relatively high temperature part of the outer periphery of each hole (when adjacent dots generate heat in that direction), more
■A smaller amount of the melted resin adheres to the relatively low-temperature portion of the outer periphery of each hole (if the dots adjacent in that direction do not generate heat). It will stick.

In contrast, the above-mentioned Japanese Patent Application Laid-Open No. 54-33117 +)
As shown in the official bulletin? Tight parrot dot 41. Fi
In the recording method of the formula, when a printing device having a dot-shaped heating element and a thermoplastic resin film are brought into close contact with each other, the film is thermally perforated, and then both are peeled off in a direction perpendicular to the contact surface, the individual heating elements A non-uniform amount of the thermoplastic resin melt along the periphery of each hole in the film corresponding to the dot tends to solidify and remain on the stencil paper made of the film.

This solidified resin melt makes the cross-sectional shapes of the side holes non-uniform with respect to each other, but may also make the planar shapes of individual holes non-uniform. Therefore, when a recorded image is formed by allowing ink to pass through the perforations made up of individual holes with non-uniform shapes, if the homogeneity of the recorded image corresponding to each perforation is insufficient, 1fL determined.

In fact, the recorded images formed by the above-mentioned simple thermal dot punching recording method were insufficient in print quality. In addition, the number of dots constituting one character is significantly increased compared to this simple thermal dot punching method, for example, 24X
In the case of 24 dots, the spacing between each dot becomes considerably shorter, so the non-uniformity of the perforation shape caused by the adhesion of the resin melt becomes even more serious, and the print quality obtained deteriorates. Further decline.

In contrast, the recording method of the present invention differs from the above-described simple thermal dot perforation method in that the thermoplastic resin film and the dot-shaped heating element are slid on each other while the film is thermally perforated. .

In the recording method of the present invention, since the thermoplastic resin film is thermally perforated while sliding with the dot-shaped heating element, both of them are separated after the thermal perforation.

The film is separated under the action of a shearing force acting in the in-plane direction of the film. Therefore, the molten thermoplastic resin constituting the film is quickly accumulated at one end of the outer periphery of each hole (the part on the opposite side to the relative traveling direction of the film with respect to the heating element), and is irregularly distributed around the outer periphery of each hole. without remaining in any shape,
A substantially constant amount and a substantially constant shape are accumulated and solidified at one predetermined end of the outer periphery.

Therefore, in the recording method of the present invention, the heptad shape and cross-sectional shape of each thermally perforated hole are maintained homogeneous, and as a result, the uniformity and reproducibility of ink passage through the thermally perforated portion consisting of these individual holes is maintained. The properties are easily maintained, and clear, high-quality recorded images are formed.

Hereinafter, the present invention will be described in further detail with reference to the drawings as necessary.

1 of 1. Figure 1 is a schematic side view showing an example of a typical apparatus system for carrying out the recording method according to the present invention by transferring a thermal ηr plastic resin film.

Referring to FIG. ff11, a thermoplastic resin film made of a stretched polypropylene film or the like is unwound from an unwinding roll 2a, and is continuously or intermittently transferred in the direction of the arrow to rolls 3a and 3b.

3c and 3d, and then wound onto the winding roll 2b.

On the other hand, on one side of the resin film 1 transferred in this way,
At a thermal perforation position between the rolls 3a and 3b, a thermal head 4, which is a heat generating member having a dot-shaped heating element 4a, is placed in contact with the rolls 3a and 3b. When the film 1 slides on the heating element 4a, heat corresponding to the desired image pattern is applied from the heating element 4a to the film, and the film 1 is uniformly thermally perforated according to the pattern, so that the film 1 is perforated faithfully to the pattern. A film perforation 1a is formed.

The thermally perforated film 1 is transferred to the right side of the figure and is superimposed on a recording medium 5 made of paper or the like at the position of the roll 3b. At the transfer position, it is held between an ink supply member such as an ink roll 6 impregnated with ink 6a and a platen 7. At this ink transfer position, the ink roll 6
The ink 6a ejected from the film 1 passes through the homogeneously formed perforations 1a of the film 1, adheres to the recording medium 5, and forms a recorded image 8 of good print quality with a bright IJ1.

The outline of the recording method for Suekan II+ is as described above.
Just to be sure, I will add an explanation of the above thermal perforation. FIG. 2 shows a graph showing the relationship between the change in the surface temperature of the unit heating element and time during one pulse period (to to t2) of the dot-shaped heating element 4a.

Referring to Figure 2, from to (at the start of voltage application) to t
s (at the end of voltage application), the surface temperature of the heating element rises rapidly by L, and the resin film 1 that comes into contact with the heating element at the thermal perforation position softens and melts, and is thermally perforated to form a hole. Ru.

Referring to FIG. 3(a), a schematic cross-sectional view of such a hole 1b, and FIG. 3(b), a schematic f-side view, since the resin film l is sliding on the heating element 4all, the temperature of the film l is The molten resin 1c, which is the constituent material, is extruded from the hole 1b onto the film surface I- at one end of the outer periphery of the hole in a direction relatively opposite to the running direction of the film 1.

Next, from time t1 to t2 (at the end of cooling) in FIG. 2, the surface temperature of the heating element decreases rapidly, so l:
The melt 1c is cooled and solidified.

The film x plane 1-ty at one end of the outer periphery of the hole 1b described above is stacked to form a hole 1b having a homogeneous cross-sectional shape and planar shape as shown in FIGS. 3(a) and 3(b). The thermal perforations 1a are formed as a dot-like pattern consisting of individual holes 1b.

The basic configuration of the recording method of the present invention has been described below. In addition to the above-mentioned configuration, a thermally poor conductor 9 made of gas or a solid such as fluororubber is inserted into the film l at the position where the perforated portion la is formed. By facing the heating element 4a through the film 1, it is possible to suppress the diffusion of the patterned heat applied to the film 1, and form a clearer dot pattern.
Alternatively, it is preferable from the viewpoint of reducing the thermal burden on the heating element 4a.

Next, the configuration of each part shown in one drawing will be explained. The thermoplastic film 1 has the necessary strength and flexibility, and has the required strength and flexibility.
Melting point by SC method (differential scanning calorimetry) is 120-4
00°C, more preferably about 150 to 300°C, thermoplastic resin films are preferably used, and specifically, for example, polyethylene films, polypropylene films,
Preferred are polyvinyl chloride film, polystyrene film, polyvinyl alcohol film, polyamide film, acetate film, polycarbonate film, polyester film, polyvinylidene chloride film, and the like.

In order to clearly form the perforations 1a in such a film 1, it is preferable to use a stretched film as the film 1, and the thickness of the film 1 is 2 to 50 lm.
degree, more preferably about 2 to 20 lm.

The thickness of the film 1 is preferably thinner in terms of reducing the thermal load on the heating element 4a when the film 1 is thermally perforated, or making the recording device more compact by making the film 1 into a cassette.

It is preferable that such a film 1 be slid on the heating element 4a at a speed of 10 mm/sec or more, more preferably 30 to 300 mm/sec.

By sliding the film 1 in this manner, each thermally perforated hole 1b is normally 1.0 mm on the film contact surface of the corresponding heating element 4a dot in terms of the size in the film relative traveling direction. It should be about 2 to 2.0 times, but
Sliding speed and pulse 11j (t o ” t in Fig. 2)
By controlling s), it is also possible to form holes smaller than the dots of the heating element 4a.

A normal thermal head 4 is preferably used as the heat generating member having the tongue-shaped heat generating element 4a. As this thermal head, for example, one character (4mm x 4mm)
When using a thermal head having 32×, 32-dots, the amount of heat applied is preferably about 0.4 to 0.9 mJ/dot.

In addition, when applying dot-shaped heat using a thermal head or the like, the thermal energy h1 supplied to the film l is adjusted by changing the head's applied force 1 dot ttr, pressure, applied pulse 1['', applied pulse period, etc. However, it is possible to control the diameter of the perforation of the perforation portion 1a. By changing the diameter of this perforation, the amount of ink passing through the perforation portion 1a at the ink transfer position can be changed to obtain a halftone recorded image 8.

If necessary, the film 1 may be attached to such a heating element 4a.
The thermally poor conductors 9 placed opposite each other have a thermal conductivity of 0.5 w/modeg or less, preferably 0.1 w/m
*deg or less, more preferably 0.05w/msdeg
Consists of the following materials. The thermally poor conductor 9 has a surface facing the film 1 made of a polymer with low thermal conductivity such as natural rubber, acrylic rubber, silicone rubber, fluororubber, vinyl chloride resin, polyamide resin, polyurethane resin, etc. members can be used. It is preferable that the poor heat conductor 9 made of such a solid has a shape of a rotating body.

Note that a gas such as air may be used as the thermally defective conductor 9. In this case, it is not necessary to arrange any solid member at the position of the thermally defective conductor 9.

The ink supply member 6 may be any member capable of supplying an appropriate amount of 11t of ink 6a to the perforated portion 1a of the fill L1 at the ink transfer position. +f can be used without restriction. As this ink supply member, an ink supply member (not shown) formed in the shape of a hollow cylinder with a constricted tip may be used, which supplies ink using an agent of 1 capillary action and 1 pressure and 1 gravity. However, the ink 6a is applied to the porous material 1.
An ink roll impregnated with is preferably used.

Porous materials used for such ink rolls include:
Porous metals, porous resins, and other porous materials commonly used in the fields of printing and recording can be used. From the point of view of smoothly supplying the ink 6a, porous rubber,
Porous elastic materials such as porous polyurethane are preferably used.

At the ink transfer position, a linear pressure of about 0.5 to 7 kg/cm may be applied to the film 1 and the recording medium 5 between the ink supply member 6 and the platen 7 as necessary. good.

The ink 6a supplied from the ink supply member 6 is supplied to the perforated portion 1a of the film at room temperature or under heating.
Use an ink with a viscosity that allows it to pass through. This ink 6a is an ink 1. having fluidity at room temperature. !
Overall, using an ink with a viscosity of about lO to 10' centipoise, or even about 102 to 104 centipoise, at room temperature forms a clear recorded image on a recording medium with a low surface slipperiness. That's pretty frightening.

Inks that are fluid at room temperature are made by dissolving or dispersing colorants such as dyes and pigments in liquid substances such as oils and solvents.
As such ink, which may contain appropriate resins, additives, etc., inks generally used in the fields of recording and printing can be used as they are.

The rolls 3a, 3b, 3c, 3d and the platen 7 are elastic rolls whose surfaces are made of nitrile rubber, polyurethane rubber, natural rubber, ethylene propylene rubber, vinyl chloride resin, nylon resin, etc. Any rigid roll made of metal, ceramics, etc. may be used.

In the above, with reference to FIG. 1, a typical aspect of an uninvented recording method, that is, an aspect in which a thermoplastic resin film l slides and runs on a fixed dot-shaped heating element 4a has been explained. However, it is easy to understand that the desired effects of the present invention can be obtained even when the film 1 is fixed and the heating element 4a is slid and moved when the film 1 is thermally perforated.

Apart from this, in order to obtain a clearer recorded image 8 in the present invention, as shown in FIG. 4, it is necessary to quickly separate the film l from the recording medium 5 on the downstream side of the ink transfer position. is preferred.

As is clear from the foresight cube 1, according to the present invention,
A recording method is provided in which a thermo-ITT plastic resin film and a dot-shaped heating element are made to slide against each other, the film is uniformly thermally perforated, and the perforations are utilized to transfer ink to a recording medium.

By using the recording method of the present invention, a clear and high-quality recorded image can be formed on the recording medium-L at low recording cost.

Hereinafter, the present invention will be explained in more detail with reference to examples and reference examples.

Example 1 Using the recording device basically shown in Fig. 4, a stretched polypropylene film 1 with a thickness of 4 μm was printed at 80 mm/sec.
While running at high speed, heat generating element 4a of 1×32 dots
Thermal energy of 0.5 mJ/dot was applied to the film 1 using a thermal head 4 having a thermal head 4, and the film 1 was thermally perforated to form perforated portions 1a. During this thermal perforation, a predetermined facing state of the thermally poor conductors was realized without placing a solid member similar to a platen on the opposite side of the film 1 to the surface facing the heating element T-4a.

Next, the film 1 was superimposed on a high-quality paper 5 (smoothness 120 seconds measured by a penkuri l smoothness meter) as the recording medium, and a commercially available ink roll 6 for cash registers (IR-71, produced by Futo Kagaku Paper Co., Ltd.) The ink flowing out from the film (manufactured by the manufacturer) is transferred to the recording medium 5 through the film perforation 1a to form a recorded image 8.
was formed.

Furthermore, as the recording medium 5, pound paper (41 smoothness 10 seconds by Beck medium slipmeter) was used instead of the Toga paper described in 1-1.
Recorded image 8 was formed 1° in the same manner as in 1-.

The Q image 8 obtained on the plain paper and the pound paper are both clear and have good print quality, and the image 1 is between the recorded image on the plain paper and the recorded image on the pound paper. No visual difference in print quality was observed.

Example: At the thermal perforation position of the film 1, the dot-shaped heating element 4
The same operation as in Example was performed, except that a stainless steel flat plate with a smooth surface was placed opposite to a with the film 1 in between.

Although thermal energy of 0.5 mJ/dot was applied to the film 1 from the heating element, the film 1 was not thermally perforated and no recorded image 8 was formed.

[Brief explanation of drawings]

FIG. 1 is a schematic side view showing an example of a typical apparatus system for carrying out the recording method of the present invention, and FIG. 2 shows the relationship between the surface temperature of a unit heating element and time in one pulse period. Graph, FIG. 3(a) is a schematic cross-sectional view of a thermally perforated portion of a thermoplastic film, and FIG. 3(b) is a schematic plan view of the thermally perforated portion.
FIG. 4 is a schematic side view showing an example of an apparatus system for carrying out a recording method according to a preferred embodiment of the present invention. l... Thermoplastic resin film, 2a... Unwinding roll, 2b... Winding roll, 3a, 3b, 3C13d-t: I-ru, 4... Heat generating member, 4a... Dot shape heating element, 5... recording medium; 6... Ink supply member, 6a... Ink, 7... Platen. 8...recorded image, 9...thermal defective conductor. ΩJ: Fig. 1 Fig. 1 Sword rum running direction Fig. 4

Claims (1)

[Scope of Claims] 1. A step of bringing a dot-shaped heating element into contact with one surface of a thermoplastic resin film and causing the heating element to generate heat in a desired pattern to thermally perforate the thermoplastic resin film in a dot shape;
A thermoplastic resin film is superimposed on a recording medium, and an ink supply member is placed to face the surface of the film opposite to the surface that contacts the recording medium, and ink is flowed out from the ink supply member to form dot-shaped perforations in the thermoplastic resin film. A recording method 2 comprising a step of allowing a thermoplastic resin film to pass through and forming a recorded image on a recording medium, and also comprising sliding the film and dot-shaped heating elements when thermally perforating a thermoplastic resin film. 2. The recording method according to claim 1, wherein when thermally perforating a thermoplastic resin film, a thermally poor conductor is placed to face the surface of the film opposite to the contact surface of the dot-shaped heating element.