JPH01105254A - Pressurizing device - Google Patents

Abstract

PURPOSE:To obtain an optimum pressure distribution in accordance with the size of an object to be pressurized of a recording material, etc. by forming the peripheral surface of the center part in the axial direction of a backup roller, to a columnar shape, and also, to plural tapered faces which are directed in both end directions from the center part and connect the respective peripheral surfaces. CONSTITUTION:The titled device is provided with a pair of pressure rollers 74, 80, and backup rollers 96, 120 on the back part of at least one of said pair of pressure rollers 74, 80, and the peripheral surface of the center part in the axial direction of the backup rollers 96, 120 is formed to a columnar shape, and also, plural tapered faces which are directed in both end directions from this center part and connect the respective peripheral surfaces. In such a state, as for the pressure rollers 74, 80, both its end parts are brought to press-contacting by elastic force of springs 90a, 90b through shafts 76, 78, and its back part is pressed by the backup rollers 96, 120 and elastic force of the spring, and bent and deformed so as to come into contact at the respective edge parts in accordance with width of an object to be pressurized. In such a way, the object to be pressurized can be pressurized so as to become an optimum pressure distribution in accordance with its width.

Description

Detailed Description of the Invention <Industrial Application Field> The present invention relates to a pressurizing method in an image recording apparatus that records an image using a recording material in which a material on which an image is fixed by pressure is coated on a support. The present invention relates to a pressure device having a pair of pressure rollers.

<Prior art and its problems> An image recording method in which a visible image is obtained by applying pressure, using a photosensitive material coated on a support with a substance on which an image formed by imagewise exposure is fixed by pressure, as an image recording material. is known, and various types of image recording materials, image recording apparatuses, etc. applied to such image recording methods are known.

Examples of such image recording materials include photosensitive materials that utilize microcapsules containing a photosensitive composition. For example, a photosensitive material using a synthetic polymer resin wall capsule containing a vinyl compound, a photopolymerization initiator, and a colorant precursor has been disclosed (Japanese Patent Laid-Open No. 57-1798
Publication No. 36).

In this photosensitive material, microcapsules are imagewise cured by exposure to light, then pressure is applied to rupture the uncured microcapsules, and a color image is formed from the released colorant precursor. It has the characteristic of being able to obtain high quality images through extensive processing.

However, this light-sensitive material has a drawback in that it has significantly lower photosensitivity than light-sensitive materials using silver halide, such as photographic emulsions.

Therefore, by improving these drawbacks and achieving high photosensitivity,
A new photosensitive material that makes it possible to obtain high-quality images through simple dry processing has been disclosed (Japanese Unexamined Patent Publication No. 61-2
75742). In this light-sensitive material, at least a photosensitive silver halide, a reducing agent, a polymerizable compound, and a color image-forming substance are coated on a support, and at least the polymerizable compound and the color image-forming substance are coated on a support. It is enclosed in a capsule.

An image recording apparatus for recording images using such a photosensitive material is disclosed in detail in Japanese Patent Laid-Open No. 147461/1983. That is, in this image recording apparatus, first, imagewise exposure is performed to form a latent image on the photosensitive material.
Next, this photosensitive material is subjected to a development process by heating, and the polymerizable compound in the area where the latent image is present is polymerized to produce a high molecular compound, thereby hardening the microcapsules. Finally, this photosensitive material and an image-receiving material having an image-receiving layer to which a color image-forming substance can be transferred are stacked and pressed together to rupture at least a portion of the microcapsules in areas where no latent image exists, thereby forming a color image. A forming substance is transferred to the attachment material to form a visible image.

Incidentally, in the image recording apparatus, in order to accurately transfer a color image forming substance onto an image-receiving material, the photosensitive material and the image-receiving material are superimposed and pressed under high pressure by a pair of pressure rollers.

In this case, the pressure roller has a considerably long structure so as to sufficiently cover the width of the photosensitive material and the image-receiving material. Therefore, when both ends of the negative pressure roller are pressed against the other pressure roller by a spring or the like, only the two edges of the pressure roller come into pressure contact due to the deflection that occurs in the pressure roller. As a result, sufficient pressing force is not applied near the center of the photosensitive material, and therefore, a situation may occur in which the color image forming substance is not accurately transferred to the image receiving material.

Therefore, an attempt has been made to correct the overall deflection of the pressure roller by pressing the center portion of the pressure roller with a backup roller having a cylindrical shape with a large diameter only at a required central portion. However, even in this case, since the central large-diameter portion of the backup roller is bent in the longitudinal direction, only both end portions of the central large-diameter portion press the pressure roller excessively, and the abutting portion of the pressed pressure roller As a result of the depression, the pressing force of the pressure roller is not uniform between that part and other parts, resulting in a drawback that the color image material is not accurately transferred to the image-receiving material.

In order to solve these drawbacks, the back-up roller has a cylindrical central part and a truncated cone-like structure whose diameter gradually decreases at both ends. A structure that presses against a pressure roller has been proposed (Japanese Patent Application No. 62-2
No. 6800).

An example of such a roller is one in which the configuration of a pressure roller and a backup roller is shown in FIG. 6, for example.

In FIG. 6, a backup roller 96.120 is provided on the back side of each of the pair of pressure rollers 74.80, and the backup roller 96.120 has a substantially circular section with the same diameter at its center. Formed in a columnar shape,
Both sides thereof are formed into a substantially truncated cone shape, with the diameter gradually decreasing toward the end. At this time,
Usually, the etched portion of the joint between the cylindrical portion and the truncated cone portion is rounded (R).

When such a backup roller is used, the center part of the backup roller is bent and the contact position with the pressure roller is the above-mentioned etched part, so even if the width of the object to be pressed changes, the contact position will not change due to the curvature of R. It varies only slightly with radius.

For this reason, it becomes difficult to obtain an optimal pressure depending on the width of the object to be pressed (eg, a photosensitive material and an image-receiving material stacked on top of each other). For example, if a wide piece has a flat pressure distribution, a narrow piece will lift the center due to flexure, resulting in insufficient pressure at the center.

It is also possible to increase the pressure, but this poses a problem in terms of strength.

Therefore, in images obtained by applying such a pressure device, uneven transfer density due to insufficient pressure or the like is observed.

Furthermore, the contact area at the etched portion of the backup roller is narrow, and the pressure distribution on the pressure roller is concentrated at one point, resulting in damage to the pressure roller.

Therefore, it is necessary to solve the above-mentioned drawbacks.

<Object of the Invention> The object of the present invention is to create a pressurizing system that can obtain an optimal pressure distribution according to the size of the object to be pressurized, such as a recording material, and as a result, can obtain high-quality images. The goal is to provide equipment.

<Brief explanation of the invention> The above objects are achieved by the invention as described below.

That is, the present invention provides a pressure device in an image recording apparatus for obtaining a visible image by pressure using a recording material in which a substance on which an image is fixed by pressure is coated on a support. a roller, and a backup roller on the back surface of at least one of the pair of pressure rollers, the backup roller has a cylindrical circumferential surface at a central portion in the axial direction, and both ends extend from the central portion. This pressurizing device is characterized in that it has a plurality of tapered surfaces that are oriented in the direction and connected to each other on their circumferential surfaces.

<Specific structure of the invention> Hereinafter, a specific configuration of the present invention will be explained in detail.

1 and 2 show an embodiment of the pressurizing device of the present invention.

As shown in FIGS. 1 and 2, the pressurizing device 1 includes a first pressurizing device fixed to a housing constituting an image recording device.
support plates 68a, 68b, and the first support plate 68a,
The support plate 68b has second support plates 72a and 72b each having one end rotatably supported via a support shaft 70.

A first pressure roller 74 that is rotationally driven by a drive source (not shown) is supported by the first support plates 68a, 68b via a shaft 76. In addition, second support plates 72a, 72
A second pressure roller 80 is rotatably supported on b via a shaft 78.

Note that these pressure rollers 74 and 80 are made of SK material or S
It is preferable to form the 0M material by induction hardening (the hardening depth is 5 mm or more from the roller circumferential surface, the hardness is HRC 60 or more), and hard chrome plating is applied to the outer periphery.

Here, holder parts 82a and 82b are formed at the ends of the first support plates 68a and 68b that are opposite to the other ends of the second support plates 72a1 and 2b, respectively.
Bolts 86 a, 86 are inserted through holes 84 a, 84 b drilled in the other ends of the second support plates 72 a, 72 b.
b is attached. In this case, bolts 86a, 86b
flange parts Baa, 88b and support plates 72a, 7 of N2.
Springs 90a and 90b are interposed between the other ends of the second support plates 72a and 172b.
8a, 68b are urged toward the holder portions 82a182b. Therefore, the second pressure roller 80 is pressed against the first pressure roller 74 by the elastic force of the springs 90a and 90b.

The pressure rollers 74 and 80 usually have a diameter of about 3 to 7 cm and an axial length of about 20 to 40 cm, and there is no limit to the circumferential speed corresponding to the conveyance speed of the recording material A and the image receiving material C.

Further, as shown in FIGS. 1 and 2, flanges having a diameter slightly larger than the circumferential surface of the pressure roller are formed at both ends of the pressure roller 74.80, and both pressure rollers 74.80 A suitable gap, so-called clearance, is provided between the circumferential surfaces. The clearance is provided to prevent uneven pressure distribution caused by the difference in width of the image receiving material C.

On the other hand, one end of each of the first holding plates 94a, 94b is rotatably supported by the first supporting plates 68a, 68b via a support shaft 92. A first backup roller 96 is rotatably supported via a shaft 98.

In this case, the first backup roller 96 has a shaft (longitudinal)
The circumferential surface of the central portion in the direction is cylindrical, and is formed from a plurality of tapered surfaces extending from the central portion toward both ends and connecting the respective circumferential surfaces. Therefore, as shown in FIG. 2, the backup roller 96 has a plurality of etched portions P-3% P' to S' formed on its circumferential surface. Such an etched portion is located symmetrically with respect to the center of the first backup roller 96 in the axial direction TT' as shown in FIG.
Plural pairs (P and P', Q and Q', R and R', S and s
), and the overall shape is symmetrical.

Such an edge portion P of the first backup roller 96
%P';Q%Q';R,R';S.

The number of S' may be determined depending on the width (in paper) of the pressurized object used. Then, according to the width of the pressurized object, the inner etched portions p, p' are arranged in order from the smaller width of the pressurized object.
This becomes the point of contact with the pressure roller 74 in order. The position of each edge portion (that is, the connection position of each tapered surface) is set so that an appropriate pressure distribution can be obtained depending on the width of the object to be pressed (in the illustrated example, a stack of recording material A and image receiving material C). Normally, the width of the object to be pressurized is 1 from the end.
The contact point may be set at a position of about 1/3 to 1/4.

Figures 3a and 3b show how the contact points differ depending on the width of the object to be pressed.

As shown in the figure, the central part (section f/, 1) between the etched parts p and p'- is formed into a substantially cylindrical shape, and on both sides there are a plurality of tapered surfaces PQ, which are oriented toward the ends. P'Q'
, QR%Q'R' , RS.

A plurality of R'S' , ST, and S'T' are integrally connected and formed.

The truncated conical tapered surface formed in this case is usually formed so that the diameter gradually becomes smaller toward the end.
This does not necessarily have to be the case, and may be determined depending on how the first backup roller 96 is bent.

In this case, the thickness, width, pressure distribution, compression ratio, pressure roller 74.80, backup roller 96.
The deflection curve of the backup roller is calculated from the axial length, diameter, nip pressure, etc. of 120, and the edge portions P, P':Q%Q';R%R';S are
.

What is necessary is to set the position of S' and its diameter.

In this case, the angle 01 to θ4 of the tapered surface is preferably 31 or less, preferably 0.6 to 2°.

In addition, the radius of curvature of the edge part PNS% P' to S' is 40
It is good to set it to 30 mm or less, preferably 30 mm or less.

Here, the holder parts 100a, 100b formed on the first support plates 68a, 68b have first holding plates 94a, 94.
A bolt 104a is inserted through holes 102a and 102b drilled at the other end of b.

104b is attached, and this bolt 104a.

A spring 108 is provided between the flange portions 106a, 106b of the flange portion 104b and the other end portion of the first holding plate 94a, 94b.
a, 108b are interposed.

Accordingly, the other end portions of the first holding plates 94a, 94b are held in place by the holder portions 100a, 100a, 100a, 108b,
100b, the first backup roller 96 presses against the back surface of the first pressure roller 74.

Note that the support shafts 92 of the first holding plates 94a and 94b have a first
A cleaning shoe 1 that comes into sliding contact with the pressure roller 74 of
10 is attached via a take-out plate 112.

Similarly, a second holding plate ttsa is connected to the second supporting plates 72a and 72b via a support shaft 114.

116b is rotatably supported, and a second backup roller 120 is rotatably supported on the second holding plates 116a, 116b via a shaft 118.

In this case, the second backup roller 120 has the same configuration as the first backup roller 96 described above.

Note that these backup rollers 96.120 are preferably formed of the same material as the pressure rollers 74.80.

Here, the holder parts 122a, 122b formed on the second support plates 72a, 72b have second holding plates 116a, 1
Bolts 126a, 126b are attached through holes 124a, 124b bored at the other end of 16b, and the flange portions 128a, 128b of the bolts 126a, 126b and the other end of the second retaining plate 116a, 116b. Springs 130a and 130b are interposed between the two parts. Therefore, the other end portion of the second holding plate 116a, 116b is held by the holder portion 122a by the springs 130a, 130b.
.

122b, the second backup roller 120 is pressed against the back surface of the second pressure roller 80. Note that a shoe 132 that slides on the second pressure roller 80 is attached to the support shaft 114 of the second holding plates 116a, 116b via a mounting plate 134.

On the other hand, in front of the second pressure roller 80, a blade 136 is provided which is rotatably supported by the first support plates 68a and 68b. The other end of the blade 136 is tensioned by a spring 138 so that one end of the blade 136 comes into sliding contact with the second pressure roller 80 . Note that a guide plate 140 is arranged opposite to this plate 136.

The force applied to the pressure rollers 74, 80 and backup rollers 9B and 120 varies depending on the thickness of the object to be pressed, etc., but the pressure applied to the object to be pressed is 450 to 600 k.
g/cm”, preferably within the range of
Usually it is about 550 kg/cm2.

More specifically, in order to obtain such a pressing force, a nip force of about 1000 kg is required for the pressing roller rough 4.80,
A nip force of about 500 kg may be applied to the backup rollers 96 and 120.

In addition, as shown in FIG. 4, the backup roller 96
In order to adjust the deflection, that is, the surface pressure against the first pressure roller 74, the tapered surface other than the vicinity of the edge portion may be removed into an arbitrary shape.

As a specific design example, the diameter of the pressure roller 74.80 is 34.
~40 mm, and when the axial length is 330 to 350 mm, the backup roller length A5 is 310 to 340 mm. Then, according to the illustrated example, among the four types of paper, for example, B
5. When making the etched part according to A4, B4, A3 (paper thickness 205 μm), fLi = 80 to 85 mm (B5
), J22 = 90-95mm (for A4), j2
3 = 105-110mm (for B4), 114 = 1
It may be about 10 to 115 mm (for A3 size).

In addition, the etched parts P (P'), Q (Q'), R(
The diameter of the circumferential surface including R' ) and S (S' ) is 40 mm in order.
~46mm, 39.7~45.7mm.

39.2~45.2mm, 38.9~44.9mm1 Also, the angles of the tapered surfaces θ1~θ4 are all 0.6~
The angle may be within a range of 3°.

The first support plates 68a, 68b further include a pair of rollers 3.
2k is installed. In this case, a guide plate 142 is provided between the first and second pressure rollers 74 , 80 and the roller pair 32 . Further, behind the roller pair 32, first and second ejection paths 144a and 144b configured in a Y-shape are provided by guide plates.

These first and second discharge paths 144a, 1
44b, a peeling claw 146 forming the peeling part 23 and having a pointed end 145 facing the roller pair 32k is attached to the support shaft 14.
8 and is rotatably supported by first support plates 68a and 68b.

FIG. 5 shows the above-mentioned pressurizing device 1 in Japanese Patent Application Laid-Open No. 62-20946.
1 and JP-A-62-147461, in which the present invention is applied to an image recording apparatus.

Note that this image recording device is disclosed in Japanese Patent Application No. 62-121284.
This method automatically performs the image forming method as disclosed in the patent specification. In this case, first, imagewise exposure is performed to form a latent image, and then development is performed by heating.
The microcapsules are hardened by polymerizing the polymerizable compound in the area where the latent image is present to produce a high molecular compound. Then, the image-receiving material having an image-receiving layer to which the color image-forming substance can be transferred is stacked and pressurized to rupture at least a portion of the microcapsules in areas where no latent image exists;
The color image-forming material is transferred to the image-receiving material to obtain an image on the image-receiving material.

The image recording apparatus shown in FIG.
(A), an imagewise exposure section 3 that imagewise exposes the recording material A conveyed from the storage section 2 (A), a thermal development device 6 that heats and develops the imagewise exposed recording material A, and accommodation of the image-receiving material C. Part 2 (C
), the pressurizing device 1 of the present invention is provided downstream of the pressurizing device 1 for superimposing heat-developed recording material A and image-receiving material C, transferring them under pressure, and peeling off recording material A and image-receiving material C after transfer. It has a recording material disposal section 7 and a fixing device 8.

The image recording apparatus of the above embodiment has a thermal development device 6 and is configured to perform the thermal development process and the pressure transfer process separately, but in the pressure device 1 of the present invention, the pressure roller 4. It is also possible to adopt a configuration in which the development and transfer process is performed simultaneously by installing a heat source at 80, for example. In addition, various configurations can be selected depending on the purpose and use.

Further, in the above embodiment, the fixing device 8 is provided, but it may be selected as appropriate depending on the photographic material used.
Depending on the case, a configuration may be adopted in which the fixing device 8 is not provided. For example, a post-heating device may be installed to improve image density.

In the image recording apparatus shown in FIG. 5, a photographic material in which a recording material as a photosensitive element and an image receiving material C as an image receiving element are provided on separate supports is used. The image receiving element and the image receiving element may be formed on the same support. Furthermore, although we have taken as an example a configuration in which both are peeled off after transfer, it may be possible to use a type that does not require peeling.

In general, the following recording materials can be mentioned as recording materials that can be used in the image recording apparatus having the pressure device of the present invention.

For example, there is a type of photosensitive material disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 57-179836 in which a polymerizable compound is imagewise cured by imagewise exposure and then pressure is applied to obtain a visible image. This photosensitive material has a synthetic polymer resin wall capsule containing a vinyl compound, a photopolymerization initiator, and a colored precursor supported on a support.

Another example is a type in which a visible image is obtained by applying pressure after preliminary thermal development or wet development of a latent image generated by imagewise exposure.

Examples of such recording materials include Japanese Patent Application Laid-Open No. 61-278
The recording (photosensitive) materials disclosed in Japanese Patent Application No. 849 or Japanese Patent Application No. 61-53881 can be mentioned. The recording material disclosed in JP-A-61-278849 is
After thermal development, a color image-forming substance is transferred to an image-receiving material having an image-receiving layer to obtain an image on the image-receiving material. An image forming substance is coated thereon, and at least a polymerizable compound and a color image forming substance are encapsulated in the same microcapsule. This recording material is particularly suitably visualized by the pressurizing device of the present invention.

Furthermore, the recording (photosensitive) material disclosed in the specification of Japanese Patent Application No. 1988-53881 is for obtaining an image on the recording material without using an image-receiving material. In other words, the image-receiving layer is provided on the recording material itself, and contains silver halide, a reducing agent, a polymerizable compound, and two types of substances that cause a color reaction when in contact with one of the substances that cause a color reaction. A photosensitive layer in which the polymerizable compound is contained in microcapsules, and other substances among the substances that cause a color reaction are present outside the microcapsules containing the polymerizable compound, is placed on the support. This is what we have. This recording material is also suitable in the present invention.

<Specific action of the invention> The operation of the pressurizing device of the present invention will be explained.

The recording material A and the image receiving material C in a superimposed state are carried into the pressure transfer section 21 by guide plates 138 and 140 and guided to pressure rollers 74 and 80.

When the superimposed recording material A and image receiving material C are pressed together by pressure rollers 74 and 80, an image is formed on the image receiving material C.

Here, both ends of the first and second pressure rollers 74.80 are connected to springs 90a and 90 through shafts 76.78.
While being pressed by the elastic force of b, each pressure roller 74
．． The rear part of 80 is connected to springs 108a, 108b and 130a via shafts 98.118 by first and second backup rollers 96.120.

It is pressed by the elastic force of 130b.

In this case, the first and second backup rollers 96.
120 is a spring 108a.

Due to the elastic force of 108b, 130a, and 130b, the first heating roller 74 and the first backup roller 9 are
6, and the second heating roller 80 and the second backup roller 120 are connected to the respective backup rollers 96.
120 edge parts P, P';Qx ci/.

It bends and deforms so that it contacts at R, R', S, and S'.

As shown in FIG. 3a, for example, when a narrow pressurized object is carried between the pressure rollers 74 and 80, the etch portion P%P
’ to make contact. Further, as shown in FIG. 3b, when a wide pressurized object is carried in, it contacts at the etched portion Q%Q'.

In this way, it is possible to suppress the object to be pressurized in a way that is suitable for the width.

Since the angle of the tapered surface of the backup roller 96, 120 is 3 degrees or less as described above, and the radius of curvature is 40 mm or less, the contact position is accurate. In addition, the contact area is wide and the pressure roller is less likely to be damaged.

Back up roller 96 on the tapered surface other than near the edge
．． It is also possible to adjust the surface pressure of the backup rollers 96 and 120 by removing them to the extent that the strength of the rollers 120 is not reduced.

The recording material A and the image receiving material C pressed by the pressure rollers 74 and 80 are transferred to the roller pair 32 via the guide plate 154.
k is carried into the peeling section 23. In the peeling section 23, the peeling claw 146 is rotated about the support shaft 148 in the direction of the arrow, thereby performing a peeling operation between the recording material A and the image receiving material C. That is, the recording material A is conveyed by the pointed end 145 of the peeling claw 146 to the discharge path 144a which leads to the recording material disposal section 7, which is not shown in FIG.

On the other hand, the image receiving material C is removed from the sharp end 145 of the peeling claw 146.
The recording material A is separated from the recording material A and conveyed to the second discharge path 144b.

<Effects of the Invention> According to the present invention, objects to be pressurized, such as recording materials having a plurality of different widths, can be pressurized with an optimal pressure distribution depending on the widths using one apparatus.

As a result, it is possible to obtain high-quality images with less occurrence of density unevenness.

Experimental Examples In order to confirm such effects, the present inventors conducted various experiments. An example is shown below.

An image recording apparatus as shown in FIG. 5 equipped with the pressurizing device 1 of the embodiment shown in FIGS. An image was formed.

Recording materials are 85 plate (width 182 mm) and A4 plate (width 210 mm).
mm), 84 version (width 257 mm) and A3 version (width 2
97 mm) and a thickness of 205 μm.

In the pressure device 1 of the present invention, the pressure roller 74.80 has a diameter of 40 mm and an axial length (L) of 342 mm (material: SCM
435), and the clearance between the pressure rollers 74 and 80 was 0.14 mm.

Also, the backup roller 96.120 has a total length J25=
326mm, length of cylindrical center Ill = 84mm
(between PP'), and the distance between the edge parts symmetrically provided across this is 12 = 93 mm (QQ
'), J13=106mm (between RR'), J24
= 114 mm (between SS'). In addition, the etched part P
(P'), Q (Q'), R(R'''), s (
s') and the diameter of the shaft end T (T') are 46 mm in order.
, 45.7mm, 45.2mm.

They were 44.9 mm and 41 mm.

Further, the angle of each tapered surface and the radius of curvature of the etched portion were determined as follows.

Etch part Tapered surface angle Radius of curvature p (p')
θ1= 2” 40mmQ (Q”I θ
2= 2° 40mmR(R”) θ3= 2°
40mm5 (s') θ4= 2°
The material of the 40 mm backup roller 96.120 was the same as that of the pressure roller 74.80.

When such a pressure device was used, good images were obtained with any size of recording material.

On the other hand, an image was formed in the same manner as in the above-mentioned image recording apparatus except that the pressurizing device was the conventional one described in Japanese Patent Application No. 62-26800, the main structure of which is shown in FIG.

In this case, the pressure device of the present invention differs only in the shape of the backup roller, and the backup roller has a cylindrical shape at the center and a truncated cone shape with a diameter gradually decreasing at both ends. It has become. The length of the central part of the cylinder is 110 mm, and the angle θ of the tapered surface of the truncated cone is 1.
．． 1°, and the joining part of the cylindrical part and the truncated conical part is rounded (
R; radius of curvature 10 mm).

When such a pressure device is used, a satisfactory image can be obtained with an A4 size recording material, but a good image cannot be obtained with a photosensitive material of other sizes due to a large amount of density unevenness.

[Brief explanation of the drawing]

FIG. 1 is a side view showing an embodiment of the pressurizing device of the present invention, and FIG. 2 is a partial front view of FIG. 1. FIGS. 3a and 3b are enlarged partial front views schematically showing how the backup roller in the pressure device of the present invention is bent in accordance with the width of the object to be pressed. FIG. 4 is an enlarged partial front view of the batter up roller in the pressurizing device of the present invention. FIG. 5 is a block diagram showing an image recording apparatus equipped with the pressurizing device of the present invention. FIG. 6 is a partial front view schematically showing a conventional pressurizing device. Explanation of symbols A...Recording material, C...Image receiving material, 1...
Pressure device, 2(A)--Recording material storage unit, 2(C)-Image-receiving material storage unit, 3-Imagewise exposure unit, 6-Thermal development device, 7-.・Recording material disposal section, 8... Fixing section, 74.80
...Pressure roller, 96.120...Backup roller, 23...Peeling part, 68a, 68b, 72a, 72b
- Support plate, 94a, 94b, 124a. 124b...retention plate, 90a, 90b, 108a, 108b. 130a, 130b - Spring FIG, 3a FIG, 3b FIG, 4 FIG, 5 FfG, 6

Claims (3)

[Claims] (1) A pressure device in an image recording apparatus for obtaining a visible image by pressure using a recording material in which a substance on which an image is fixed by pressure is coated on a support, which includes a pair of pressure rollers. , and a backup roller on the back surface of at least one of the pair of pressure rollers, and the circumferential surface of the axially central portion of the backup roller is cylindrical, and from the central portion toward both ends. A pressurizing device characterized by having a plurality of tapered surfaces that are oriented and connect their peripheral surfaces. (2) Pressure according to claim 1, wherein the recording material generates a distribution of microcapsules with different degrees of hardening by heat development, and a visible image is obtained by applying pressure with a pressure roller according to this distribution. Device. (3) The pressurizing device according to claim 2, wherein the recording material and the image-receiving material are superimposed and pressed by a pressure roller to obtain a visible image on the image-receiving material.