JPS6275637A - Production of cylindrical printing plate - Google Patents

Abstract

PURPOSE:To easily and simultaneously obtain a cylindrical printing plate which has uniform quality in the circumferential direction and has no seams by supplying a photosensitive resin to the inside of a cylindrical body, rotating the cylindrical body at a high speed to uniformly stick the resin liquid in the cylindrical body and subjecting the cylindrical body to back exposure and relief exposure while said body is kept rotated. CONSTITUTION:A supply means 22 in which the photosensitive resin liquid A is contained is passed through the cylindrical body 1 and is set. While the cylindrical body 1 is rotated at a low speed by a motor 12, the supply device is gently turned upside down to pour the photosensitive resin A, then the means 22 is pulled out of the cylindrical body and a high pressure mercury lamp 10' is inserted into this position. The cylindrical body 1 is rotated at a high speed so that the photosensitive resin A is uniformly stuck to the inside surface of the cylindrical body 1 by centrifugal force. The cylindrical body 1 is subjected to back exposure and relief exposure by the irradiation of a chemical lamp 10 while the high-speed rotation of the cylindrical body is continued in this state. The lamp 10' is pulled off and the rotation of the cylindrical body 1 is stopped. A base 27 (seamless woven fabric) is inserted to the inside surface of the cylindrical body 1 and an IR lamp is inserted into the point from which the lamp 10' is removed to solidify an adhesive agent.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for producing seamless cylindrical printing plates for use in flexographic printing and other purposes.

BACKGROUND OF THE INVENTION Conventionally, the following method is known as a method for manufacturing seamless resin plates for letterpress printing, especially flexo printing, using photosensitive resin.

(i) A method in which a photosensitive resin layer is formed on a cylindrical support member by external coating, and then this layer is subjected to relief exposure. For example, on a steel cylinder a predetermined thickness of, for example, about 1.
A method in which a single layer of cured polymer having a thickness of 5 mm) is attached using an adhesive, an uncured photosensitive resin layer is coated on top of it to a predetermined thickness (for example, about 1.0 mm), and this layer is then exposed to relief light.

(ii) wrapping a photosensitive resin sheet around a cylindrical support member;
A method in which the seams are joined together by heating and pressure, and then this sheet is exposed to relief light. For example, an unexposed photosensitive resin sheet is wrapped precisely along the outer diameter of a cylinder, a shrink film is wrapped over this, and then the sheet is softened and the bonded area is homogenized by applying reduced pressure and heat. A method in which the surface is smoothed using a calender processing device, and then this sheet is exposed to relief light.

(i i i) A method in which a liquid photosensitive resin solution is filled in the gap between the outer tube and the inner tube of the double tube and solidified, and then this solidified layer is subjected to relief exposure.

Problems to be Solved by the Invention However, in the method (i) above, a seam is created when the cured photosensitive resin sheet is pasted onto the cylinder, so an uncured photosensitive resin layer is coated on top of the seam. Sometimes, the film thickness tends to be uneven at the joints, and in order to coat an uncured photosensitive resin layer to a predetermined thickness, coating and drying operations must be repeated many times. There are problems in that the process operations are complicated and it is difficult to achieve uniform coating thickness.

In addition, in the method of 11) above, it is difficult even for an expert to wrap an unexposed photosensitive resin sheet around a cylinder and match both ends accurately, and heat is applied to homogenize the joint. This may impair the quality of the unexposed sheet, and furthermore, since the bonded portion is not strictly homogeneous, there is a risk that it will be difficult to obtain a fine, continuous-tone image.

Furthermore, in the method (item 1), a high degree of dimensional accuracy is required to create the double tube in order to make the film thickness uniform." 2. The resulting cylindrical photosensitive resin sheet is susceptible to air bubbles. There are some drawbacks.

The methods (i), (1i), and (iii) above all involve two steps: a photosensitive layer formation process and an exposure process, so they have the problem of complicating the printing plate manufacturing process. Ta.

74:, In view of such circumstances, the invention was made in order to find an industrially advantageous method for manufacturing seamless cylindrical printing plates with uniform film thickness all at once.

To solve the problem, the method for producing a cylindrical printing plate according to the present invention is based on the method of producing a seamless cylindrical printing plate by applying a photosensitive resin liquid inside a cylindrical body that is transparent to active light. The photosensitive resin liquid is uniformly applied to the inner surface of the cylinder by centrifugal force by rotating the No. 1 cylinder at high speed.
Let it flow to form a layer of photosensitive resin liquid, and at the same time, actinic light is emitted from inside the cylinder! ! ((by exposing the photosensitive resin liquid layer from the inside by hanging it, and then irradiating the layer of the photosensitive resin liquid from the outside of the cylinder through the image carrier with relief exposure from the outside) It is characterized by the fact that ・By finding a specific Kanono such as 2, I was able to achieve the 11th goal mentioned in .

In addition, k shot 1! In this case, the following measures (a) or (b) can be taken to reinforce the damaged cylindrical printing +jM from the inside.

(b) After exposing the photosensitive resin liquid layer from the inside by irradiating actinic rays from inside the cylinder, a resin liquid for forming a support is further supplied to the inside of the cylinder, and this cylinder is It is rotated at high speed to uniformly adhere the support-forming resin liquid to the inner surface of the cylinder by centrifugal force to form a layer of the support-forming resin liquid, and then this layer is cured.

(b) After exposing the photosensitive resin liquid layer from the inside to 7 by irradiating actinic rays from inside the cylindrical body, a cylindrical support having an outer diameter that can come into contact with the exposed layer is inserted.

Hereinafter, the method for manufacturing the cylindrical printing plate of the present invention will be explained in detail.

The following types of photosensitive resin liquids are used in the present invention.

(a) Koton combination b consisting of a combination monomer and a polymer
3i, system Types belonging to this system include, for example, a type in which a Nakamiya fatty monomer is photopolymerized in a polymer matrix, a type in which a polyfunctional monomer is photopolymerized in a polymer matrix, or a type in which a monofunctional monomer is added to this. Examples include a type in which a monofunctional monomer is photopolymerized in a prepolymer, a type in which a polyfunctional monomer and a monofunctional monomer are photopolymerized in a prepolymer, and a type consisting of a prepolymer and a polymer.

ffi Polymerizable monomers include acrylic esters of polyhydric alcohols, urethane-type acrylic esters, unsaturated esters of polyhydric carboxylic acids, unsaturated acid amides, and acetylenically unsaturated group-containing monomers.

Examples include glycidyl group-containing polymers, and examples of polymers include epoxy resins, polyesters, polyurethanes, polyethers, polyamides, polyacrylic acid or dileic acid copolymers, silicone resins, cellulose resins, and synthetic rubber polymers. Examples include various polymers or prepolymers.

(b) A system consisting of a photosensitive compound and a polymer.Those belonging to this system include those that use a modified ROM salt resistant compound as a photosensitive compound, those that use an aromatic diane compound, those that use an aromatic azide compound, and those that use an aromatic azide compound. Examples include those using halogen compounds, and those using cross-linking of unsaturated polymers using a photoinitiator.

(C) A system consisting of a polymer having a photosensitive group Examples of polymers that are suitable for this system include polymers having a cinnamoyl group, polymers having a diane group, and polymers having an azide group.

In the present invention, a cylindrical printing plate is manufactured using such a photosensitive resin liquid in the following manner.

That is, a cylindrical body that is transparent to actinic rays is arranged so that its center line is substantially horizontal, and while the cylindrical body is rotated at low speed, a photosensitive resin liquid is poured into the cylindrical body using a suitable supply tool. Rotate the cylinder at high speed. Due to this high-speed rotation, the photosensitive resin liquid adhering to the inner surface of the cylinder is diffused by centrifugal force onto the inner surface of the cylinder, and a layer having a uniform thickness of 11Q is formed without containing air bubbles. A coating layer may be previously formed on the inner surface of the cylinder to facilitate peeling.

The actinic rays herein refer to ultraviolet rays, X-rays, electron beams, and the like. In addition to various inorganic glasses, polymethyl methacrylate,
Organic glass made of polystyrene, polyolefin, polyvinyl chloride, etc. is used.

Note that if the system is brought to a reduced pressure condition while the cylinder is rotating, the possibility of air bubbles entering the photosensitive resin layer to be formed is further reduced.

When a uniform layer of photosensitive resin liquid is formed on the inner surface of the cylinder,
By irradiating active light from inside the cylinder, the layer of photosensitive resin liquid is back-exposed from the inside. Note that, prior to the back exposure, a masking exposure may be performed by irradiating actinic rays from inside the cylinder through a masking film to form a base for supporting the relief. Then, at the same time as or before or after the back exposure, the photosensitive resin liquid layer is subjected to relief exposure from the outside by irradiating actinic rays from the outside of the cylinder through the image carrier (negative or positive film).

When the active light is ultraviolet rays, the light source used includes a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a carbon arc lamp, a canon lamp, a metal halide lamp, a chemical lamp, and a black light.

After completing the two series of puncture exposure and relief exposure, remove the photosensitive resin liquid exposure layer from the inner surface of the cylinder, wash off the unexposed areas by spraying onsured liquid, and dry and dry as necessary. By performing post-exposure, the desired seamless cylindrical printing plate can be obtained.

If the cylindrical body is slightly tapered, by controlling the viscosity of the photosensitive resin liquid and the rotational speed of the cylindrical body, it is possible to create f, which has a slight taper rather than a right cylindrical shape.
: Since it is possible to obtain an r-shaped printing plate or a cylindrical printing plate in which the film thickness gradually increases from one end to the other, it is possible to easily attach the device to the cylinder and remove it from the cylinder during use.

Therefore, in the present invention, after the layer of the photosensitive resin liquid is exposed from the inside by irradiating actinic rays from inside the cylinder (if after the end of the puncture exposure, the end of the relief exposure riFj, the end of the relief exposure (2) Furthermore, a resin liquid for forming a support is supplied inside the cylinder, and the cylinder is rotated at high speed to uniformly distribute the resin liquid for forming a support on the inner surface of the cylinder by centrifugal force. (b) A cylindrical support having an outer diameter that can come into contact with the pack exposure layer is inserted into the cylindrical body by forming a layer of the resin liquid for forming a support in step 16 and then curing this layer. You may also do so. This is because the resulting cylindrical printing plate will be reinforced from the inside.

In the case of (b), after inserting the cylindrical support, it is also possible to supply a resin liquid inside the cylindrical support and solidify it while dispersing it uniformly using a distance force, thereby reinforcing the cylindrical support. can.

- [The cylindrical support in (b) includes a cylindrical seamless fabric obtained by hollow weaving, a cylindrical fully flexed mesh body, a cylindrical metal menki 1 steel body, and a cylindrical plastic 1 steel body. body,
An example is a cylindrical lPtm type.

The tubular printing plate without seams obtained by the uninvented method is useful as a resin plate for letterpress printing, especially as a resin plate for flexo printing, and is also useful as a resin plate for rotary screen printing and a resin plate for intaglio printing. It can be used for lithography, resin plates, and other purposes.

The photosensitive resin liquid supplied inside the working cylinder is diffused onto the inner surface of the cylinder by centrifugal force when the cylinder is rotated at high speed, forming a layer with a uniform thickness that does not contain air bubbles.

Then, while rotating the cylinder, actinic rays are irradiated from inside the cylinder, so that the layer of photosensitive resin liquid is pack-exposed from the inside, and actinic rays are irradiated from the outside of the cylinder through image 1 [1]. By doing so, the layer of photosensitive resin liquid is exposed in relief from the outside.

After the exposure is completed, collect the resin in the unexposed areas as appropriate.

Roughly speaking, by washing off this unexposed portion, a cylindrical printing plate that is completely uniform in the circumferential direction and has no seams can be obtained.

Example Next, the present invention will be further explained with reference to Examples.

Example 1 Fig. 1 is a partially cutaway front view of an example of the apparatus used in carrying out the method of the present invention, Fig. 2 is a left side view thereof, and Fig. 3 is a side view of the y section. It is an explanatory diagram.

(1) is a cylinder made of crow, arranged so that its center line is horizontal, and its end side surface is closed by a side plate (2).Cylinder (1) is configured to allow low and high speed rotation 1 around l+(3), which is attached to the outside of the side plate (2). The provided image carrier is negative or positive film.

(4) is a weir provided inside the free end side of the body ('1). Although not shown in the drawings, instead of or together with this weir (4), a removable part with an open center may be provided.

(5) is a box that covers the entire cylindrical body (1), and a door (6) is provided on the free end side of the cylindrical body (1), and this door (6) has a window (7) made of a glass plate. ) is the installation. (8) is a handle L that opens and closes this door (6), and (9) is a hinge.

(10) is a chemical lamp as an example of an actinic ray irradiation source provided in large numbers inside the box (5).

Also, 1st to 21st. In X1, (11) is the base, (12) is the motor that rotates the rotating shaft (3), (13
) is the pulley attached to the drive shaft of the motor (12), (14) is the pulley attached to the rotating shaft (3),
(+5) are these two pulleys (13), (1
4) is a belt with 41 omitted. (16) is the operation panel, (17) is the switch, (18) is the vacuum gauge, (1
9) is a speed tachometer, and (20) is a temperature control. (21) is a temperature sensor installed at 1' and (3).

- (22) indicated by a chain line is a supply tool for supplying the photosensitive resin liquid into the inside of the cylinder (1).

After the supply tool (22) is removed, a high-pressure mercury lamp (10''), which is an example of an actinic ray irradiation source, is inserted and installed at this position.

Figures 4 and 5 show the cylindrical body (
1) shows an example of a supply tool for supplying photosensitive resin liquid into the interior of the device, and FIG. 4 is a cross-sectional view in the direction 11],
Figure 5 is a 1m partial cross-section in the length direction, (22)
(A) is a long "spike" shaped supply tool, and (A) is a photosensitive resin liquid.

A cylindrical photosensitive resin structure was manufactured in the following manner using the apparatus described in L.

Open the door (6) of the box (5) and insert the supply tool (22) containing the photosensitive resin liquid (A) into the back of the cylinder (1) as shown by the dashed line in Figure 1. Insert until the motor (12)
While rotating the barrel (1) at a low speed of 10 rpm, gently turn the supply tool (22) over to pour in the photosensitive resin liquid (A), then pull out the supply tool (22) and apply high pressure to this position. A mercury lamp (10') was inserted. Cylinder (1) 1. The photosensitive resin liquid (A
) was uniformly adhered to the inner surface of the cylinder (1) by centrifugal force.

This situation! While continuing the high speed rotation of the cylinder (1) at A;,
If necessary, the vacuum gauge (17) is operated to place the inside of the box (5) and cylinder (1) under reduced pressure conditions, followed by relief exposure by irradiation with a chemical lamp (IO) and high pressure mercury lamp (10'). Puncture exposure was performed using irradiation. The exposure time was longer for puncture exposure.

After the exposure was completed, the cured cylindrical structure was peeled off and pulled out from the cylinder (1), a washout liquid was sprayed on its outer peripheral surface to wash away the uncured portion, and then water was sprayed and rinsed. After drying, the cylindrical structure was set on a rotating body, and its outer peripheral surface was irradiated with ultraviolet rays for post-exposure. As a result, a cylindrical printing plate with a thickness of 7.0 mm was obtained.

Embodiment 2 FIG. 6 is a partially cutaway front view showing another example of the apparatus used in carrying out the method of the present invention, and FIG. 7 is a left side view thereof.

(1) is a glass cylindrical body, arranged so that the center line is homogeneous, and supporting rolls (
23) It is supported by... (C) is a cylinder (
1) Negative or positive film as an image carrier provided in close contact with the outer periphery of the film. A driven cap (24) is provided on the outer periphery of the proximal end side extension of the cylinder (1). In addition, the cylindrical body (
1) Both ends of the inner circumference are constructed in different steps to form a weir (4).

A drive gear (25) is attached to the box (5) below the proximal extension of the cylinder (1) so as to rotate together with the drive shaft (2B). The driven gear (24) matches this drive gear (25) by 1 m.

In the figure, the meanings of other symbols are the same as in FIGS. 1 to 3.

Figures 8 and 9 show the cylindrical body (
1) shows an example of a supply tool for supplying photosensitive resin liquid into the interior of the device, and this supply tool has a C-shaped cross section. FIG. 8 is a cross-sectional view in the 111 direction, and FIG. 9 is a partial cross-sectional view in the longitudinal direction. (22) is a long "spike-shaped" supply tool, and (A) is a photosensitive resin liquid.

Using the above apparatus, a cylindrical printing plate was manufactured in the following manner.

The supply tool (22) containing the photosensitive resin liquid (A) is inserted into the cylinder (1).
), and while operating the motor (12) and rotating the cylinder (1) at low speed at EiOrpm, gently turn over the tip of the supply tool (22) containing the photosensitive resin liquid (A). Pour the photosensitive resin @ (A), then add the supply tool (22)
was pulled out and a high pressure mercury lamp (10') was inserted at this position.

Next, when the cylindrical body (1) was rotated at a high speed of 60 rpm, the photosensitive resin liquid (A) uniformly spread over the inner surface of the cylindrical body (1) due to centrifugal force, resulting in a 7+ point. While continuing high-speed rotation of the cylinder (1), first pack exposure was performed using j+41° radiation from the high-pressure mercury lamp (10'), and then 11() from the chemical lamp (10).
(Relief exposure was performed using radiation.

After completing the exposure, turn off the high pressure mercury lamp (to') and -[-1
, the cylindrical support (27) rotates at the 11th rotation of the cylindrical body (1).
As an example, a cylindrical seamless fabric (fabricated by bag weaving, and the outer surface of the fabric is coated with a contacting agent/[i, which can contact the layer formed in -)-- Insert the infrared lamp into the place where the high-pressure mercury lamp (to') was pulled out, and then insert the infrared lamp into the tube (1) so that it fits perfectly with the resin layer formed on the inner surface of the tube (1). body(
At the same time as restarting the rotation of the cylinder (1), the adhesive was solidified by irradiation with an infrared lamp. After the adhesive had solidified, the rotation of the cylinder (1) was stopped and the cylinder (1) was
When the cylindrical structure was peeled off and pulled out from 1), it was found that the cylindrical structure had a photosensitive resin cured layer (B) laminated on the outer peripheral surface of the cylindrical support (27), and the cross-sectional view was made smaller as shown in Fig. 10. Since a shaped structure was obtained, a washout liquid was sprayed on the outer periphery m1 to wash away the uncured portion, and then water was sprayed and rinsed. After drying, the cylindrical structure was placed on a rotating body, and its outer peripheral surface was irradiated with ultraviolet rays for post-exposure.

As a result, a cylindrical printing plate having a thickness of G and Omm was obtained.

Example 3 After completing the exposure in Example 2, the high-pressure mercury lamp (10') was pulled out, and a supply tool (22) containing a polyurethane resin liquid as an example of a resin solution for forming a support was inserted, and the supply tool was turned over once. (22), then rotate the cylindrical body (1) at high speed to uniformly adhere the polyurethane resin liquid to the inner surface by centrifugal force to form a layer, and insert an infrared lamp to irradiate this layer. hardened.

After curing is completed, the rotation of the cylindrical body (1) is stopped and the cylindrical structure is pulled out from the cylindrical body (1) by -J1ml, and the photosensitive resin is cured on the outer peripheral surface of the cylindrical support (27). A cylindrical structure with layer (B) laminated as shown in the cross-sectional view in Figure 10 was obtained, and the outer peripheral surface was sprayed with a washout liquid to wash away the uncured parts, and then water was sprayed and rinsed. I washed it. After drying, set the cylindrical structure on a rotating body,
Post-exposure was performed by irradiating the outer peripheral surface with ultraviolet light. As a result, a cylindrical printing plate with a Pl of 5.0) was obtained.

Effects of the Invention The method of the present invention supplies photosensitive VI411J liquid to the inside of a cylinder, rotates the cylinder at high speed, causes the photosensitive resin liquid to uniformly adhere to the inner surface of the cylinder by centrifugal force, and Since puncture exposure and relief exposure are performed in a rotating state, a cylindrical printing plate that is completely uniform in the circumferential direction and has no seams 1.1 can be easily obtained in part.

In addition, it is possible to obtain any thickness from a single piece to a thick one in one step, so it is possible to use the conventional method of applying photosensitive resin liquid in multiple layers, joining the ends by wrapping, etc. Alternatively, it is much easier to manufacture than the method of filling the gap between the outer tube and the inner tube of the double-layered tube with a liquid photosensitive resin.

Therefore, J:, Il! The uniformity of J thickness is extremely excellent.

Furthermore, since the curing of the photosensitive resin layer is reduced by 1% by exposing the cylindrical body to light while rotating at high speed, there is also the advantage that no air bubbles remain in the resulting cylindrical printing plate.

Therefore, the present invention greatly contributes to the field of using cylindrical printing plates, especially the field of using flexographic printing plates.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway front view showing an example of an apparatus used in carrying out the method of the present invention, and FIG. 2 is a left side view thereof.
FIG. 3 is a side view of the main parts. Figures 4 and 5 show the cylindrical body (
1) shows an example of a supply tool for supplying photosensitive resin liquid into the inside of the device, and is a cross-sectional view in the direction of FIG.
FIG. 5 is a partial longitudinal sectional view. FIG. 6 is a partially cutaway front view showing another example of the apparatus used in carrying out the uninvented method, and FIG. 7 is a left side view thereof. Figures 8 and 9 show the cylindrical body (
1) shows an example of a supply tool for supplying photosensitive resin liquid into the interior of the device, in which FIG. 8 is a cross-sectional view in the width direction, and FIG. 9 is a cross-sectional view in the width direction.
The figure is a partial cross-sectional view in the longitudinal direction. FIG. 10 is a cross-sectional view of the cylindrical structures obtained in Example 2 and Example 3. (1)...Cylinder body, (2)...Side plate, (3)...Rotating shaft, (4)...Weir, (5)...Box body, (6)...
・Door, (7)...window, (8)...handle, (9)...
・Hinge, (10). '(10')... Actinic ray irradiation source, (11)... Base, (12)... Motor, (+3),
(14)...Pulley, (15)...Belt, (
16)...Operation panel, (17)...Switch,
(18)...Vacuum gauge, (19)...Speed tachometer, (20)...Temperature control, (21)...
... Temperature sensor, (22) ... Supply tool, (
23)... Support roll, (24)... Driven gear, (
25)... Drive gear, (26)... Drive shaft, (27
)...Tubular support, (A)...Photosensitive resin liquid, (B
)...Photosensitive resin cured layer, (C)...Image carrier patent applicant Atsushi Kitamura rT') Representative Patent attorney Seibu Oishi j:i, :,,j"
.

Claims (1)

[Claims] 1. In manufacturing a seamless cylindrical printing plate, a photosensitive resin liquid is supplied inside a cylindrical body that is transparent to actinic rays, and the cylindrical body is rotated at high speed to generate a centrifugal force. The photosensitive resin liquid is uniformly adhered to the inner surface of the cylinder to form a layer of the photosensitive resin liquid, and the layer of the photosensitive resin liquid is back-exposed from the inside by irradiating active light from inside the cylinder. A method for producing a cylindrical printing plate, characterized in that the layer of photosensitive resin liquid is exposed in relief from the outside by irradiating actinic rays from the outside of the cylindrical body through an image carrier. 2. After the layer of photosensitive resin liquid is back-exposed from the inside by irradiating actinic light from inside the cylinder, a resin liquid for forming a support is further supplied inside the cylinder, and the cylinder is rotated at high speed. to uniformly adhere the support-forming resin liquid to the inner surface of the cylinder by centrifugal force to form a layer of the support-forming resin liquid,
The method for producing a cylindrical printing plate according to claim 1, characterized in that this layer is then cured. 3. A patent characterized in that after a layer of photosensitive resin liquid is back-exposed from the inside by irradiating actinic rays from inside the cylinder, a cylindrical support having an outer diameter that can come into contact with the exposed layer is inserted. A method for producing a cylindrical printing plate according to claim 1.