JPH11123807A - Plate-making device and printing system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a plate-making device for performing offset printing which does not require an alkaline developer, then produces a high quality printed image whose image area and non-image area are sharply identifiable and can use a master plate for printing repeatedly. SOLUTION: A master plate 3 with a thin coat composed mainly of titanium oxide and zinc oxide on the surface is entirely exposed to an active light by an active light emission part 5 in a plate-making device 1 to turn the surface hydrophilic. After that, an image is drawn in the heat mode by a heat-sensitive recording part 6 and thereby, a non-image area which is hydrophilic and an image area which is lipophilic, to which the active light is emitted, are formed on the master plate 3. The master plate 3 is conveyed to a printing device 2, then an ink and a moistening water are supplied to the master plate 3 and thus are borne by the master plate 3 to perform a printing operation. After its completion, the residual ink is cleaned off the master plate 3 by an ink cleaning part 17 and the cleaned master plate 3 is returned to the make-up device 1. Consequently, it is possible to perform the printing operation by using the master plate 3 repeatedly.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to the field of general light printing,
More particularly, the present invention relates to offset printing, particularly to a novel plate-making apparatus capable of easily producing a printing plate and a printing system using the plate-making apparatus, and particularly to a plate-making apparatus and a printing system capable of repeatedly using a printing plate. It is.

[0002]

2. Description of the Related Art Offset printing is one of the main printing methods that has been widely used because of the simple manufacturing process of a printing plate among many printing methods. This printing technique is based on the immiscibility of oil and water, with the oily material or ink being selectively retained in the image areas and the dampening solution in the non-image areas. Therefore, when the printing surface is brought into direct contact with the surface to be printed or indirectly through an intermediate called a blanket, the ink in the image area is transferred to the printing substrate and printing is performed.

The main method of offset printing is a PS plate having an aluminum substrate as a support and a diazo photosensitive layer applied thereon. In the PS plate, the aluminum substrate is used as a support, the surface is grained, anodized, and other processes are performed to increase the ink receiving capacity in the image area and the ink repulsion in the non-image area, and improve the printing durability. Then, processing such as making the printing surface finer is performed, and a printing image is formed on the surface. Therefore, offset printing has characteristics such as printing durability and high definition of the printing surface in addition to simplicity.

[0004] However, with the spread of printed matter, further simplification of the offset printing method has been demanded, and many simple printing apparatuses have been proposed.

[0005] Typical examples thereof include a copy offset offset printing plate commercially available from Agfa-Gevaer, and a silver salt diffusion transfer method disclosed in US Pat. No. 3,511,656 and JP-A-7-56351. This printing device is based on printing plate preparation. According to this printing device, a transfer image can be formed in one process, and since the image is lipophilic, it can be used as it is as a printing plate. Practical printing devices. However, although simple, this apparatus also requires a diffusion transfer development step using an alkali developer, and thus a simpler printing apparatus that does not require a development step using a developer is demanded.

[0006] The development of a simplified printing plate in which the development step using an alkali developer after image exposure has been performed has been developed from the above background. In the technical field of this simple printing plate, which is called an unprocessed printing plate because the developing step can be omitted, there have been mainly (1) image formation by thermal destruction of an irradiated portion on an image recording surface by imagewise exposure, and (2) image formation. Formation by lipophilicity (heat mode curing) of the irradiated part by uniform exposure,
(3) A method based on various principles such as lipophilicity of the irradiated portion but by light mode curing, (4) change in surface properties due to photolysis of diazo compound, and (5) heat mode fusion thermal transfer of the image portion. Has been proposed.

[0007] The technology disclosed as the above simple offset printing apparatus includes US Pat. No. 3,506,779.
No. 3,549,733 and No. 3,574,65
No. 7, No. 3,739,033, No. 3,832, 9
No. 48, No. 3,945,318, No. 3,962,
Nos. 513, 3,964,389 and 4,03
No. 4,183, No. 4,081,572, No. 4,6
Nos. 93,958, 4,731,317 and 5,
U.S. Patents such as 238,778, 5,353,705, 5,385,092, and 5,395,729, and European Patent 1068.

[0008]

These are designed so that a developing solution is not required at the time of plate making, but the difference between the lipophilic region and the hydrophilic region is insufficient, and therefore the image quality of the printed image is low. Poor print quality, poor resolution and difficulty in obtaining a printed image with excellent sharpness, insufficient mechanical strength of the image surface, and easy damage, and a loss of simplicity due to the provision of a protective film. It has one or more disadvantages, such as insufficient durability that can withstand long-time printing, and indicates that simply eliminating the alkali developing step does not accompany practicality. A strong demand for a printing plate preparation method that has various characteristics required for printing and that can easily produce a printing plate has not yet been satisfied.

[0009] As the above-mentioned non-process type printing plate making method,
Japanese Patent Application Laid-Open No. Hei 9-169098 discloses a printing plate making method utilizing the fact that zirconia ceramics become hydrophilic by light irradiation.
Issue. However, the light sensitivity of zirconia is insufficient, and the effect of converting light from hydrophobic (lipophilic) to hydrophilic is insufficient, so that discrimination between an image region and a non-image region is insufficient.

If there is a simple printing apparatus which does not require the above-mentioned developer and a means for easily reusing and reusing a used printing original plate, it is advantageous from the two aspects of cost reduction and waste reduction. It is. To recycle the original printing plate,
Although the simplicity of the reproduction operation affects the practical value, the simplification of the reproduction operation is a difficult task, and has not been studied so far.
No. 8 only discloses a special stencil material called zirconia ceramic.

The present invention has been made in view of the above circumstances, has simplicity not requiring an alkaline developing solution, has an image quality sufficient for a practical level, and can repeatedly use an original printing plate. Plate making apparatus and printing system using this plate making apparatus, specifically, firstly, it does not require an alkali developing solution, has second excellent resolution, and thirdly distinguishes image areas from non-image areas. It is an object of the present invention to provide a plate making apparatus and a printing system capable of producing a print screen with high quality and excellent image quality.

[0012]

Means for Solving the Problems To achieve the above object, the present inventors have conducted intensive studies and as a result, the phenomenon that the hydrophilicity of the surface is changed by light irradiation and the changed hydrophilicity are based on heat treatment. Recognizing the existence of a material having the property of returning, and finding the possibility of solving the above-mentioned problem by applying the former to printing and using the latter for the reproduction of the printing original plate, the present invention was based on this. It is a thing.

That is, the plate making apparatus according to the present invention has a printing original plate which has a thin film mainly composed of a material which changes from lipophilic to hydrophilic by a photocatalytic reaction on its surface and is detachably provided; The printing apparatus further comprises: an exposing means for exposing the entire surface of the original using active light; and a drawing means for performing heat mode drawing on the printing original which has been entirely exposed by the exposing means.

Here, "a material that changes from lipophilic to hydrophilic by a photocatalytic reaction" means that the surface changes from lipophilic to hydrophilic by light irradiation, and the changed hydrophilic becomes lipophilic by heat treatment. This refers to a material having the property of returning to the original state. The active light is light that is excited when the material absorbs the light and changes the surface of the material from lipophilic to hydrophilic. Further, the entire surface exposure is an exposure in which substantially uniform and local nonuniformity is practically not recognized over the entire surface of the printing original plate. In addition, the heat mode is used in a sense commonly used in the art, and in addition to a method in which a fine heating element is brought into contact with an image to raise the temperature, an absorbed light is converted into heat energy. As a result, it also includes a method utilizing a thermal change instead of a photochemical change.

In the plate making apparatus according to the present invention,
It is preferable that the printing original plate is a plate-like original plate detachably provided on a surface of a drum, and the exposing means and the drawing means are arranged around the drum.

Preferably, the printing original plate is a plate cylinder, and the exposure means and the drawing means are arranged around the plate cylinder.

Further, the drawing means may be a heat-sensitive head, or may be made of a laser such as an infrared ray.

It is preferable that the material that changes from lipophilic to hydrophilic by the photocatalytic reaction is made of titanium oxide or zinc oxide.

Further, it is preferable that the apparatus further comprises an ink removing means for removing the ink remaining on the printing master after printing is completed.

The printing system according to the present invention includes a plate making apparatus according to the present invention as described above, holding means for detachably holding the printing original plate removed from the plate making apparatus, and a printing apparatus in which the heat mode drawing is performed. A printing apparatus provided with ink supply means for supplying ink to the printing plate to form an image area on the printing plate; and an ink removing unit for removing ink remaining on the printing plate after printing is completed. It is characterized by the following.

Further, in the printing system according to the present invention, the ink removing means may be provided in the printing device or in the plate making device.

Further, it is preferable that the printing system according to the present invention includes at least four printing devices.

[0023]

According to the plate making device of the present invention and the printing system using the plate making device, the entire surface of the printing original is exposed to actinic light, whereby the surface of the printing original becomes hydrophilic from lipophilic. Changes to Then, by performing drawing in the heat mode by the drawing means on the printing original plate, a non-image region having hydrophilicity by irradiation with active light and an image having the original lipophilicity by performing drawing in the heat mode An area is formed on the surface of the printing master. Then, by removing such a printing original plate from the plate-making apparatus and holding the printing apparatus to supply ink, the ink is held only in the lipophilic image area,
The ink is not held in the hydrophilic non-image area, and in this state, the image area formed on the printing original plate can be transferred to the printing substrate. After printing,
The ink remaining on the printing plate is removed by the ink removing unit, and thereafter, the printing plate is returned to the plate making apparatus, and the entire surface of the printing plate is exposed again by the exposure unit, so that the surface of the printing plate becomes hydrophilic, The drawing unit is in a state where drawing in the heat mode is possible.

Therefore, according to the plate making apparatus and the printing system of the present invention, a printed screen can be formed only by activating the entire surface of the light and drawing in the heat mode, thereby eliminating the need for development and sharpness of the printed surface. Can be performed while maintaining offset printing. Also, after cleaning the printing plate, by exposing the entire surface to actinic light, it is possible to return to the state before drawing in the heat mode,
The printing original plate can be used repeatedly, whereby the printed matter can be provided at low cost.

Further, the printing original plate is used as a plate-shaped original plate, and the original plate is detachably provided around a drum. Alternatively, the printing original plate is used as a plate cylinder, and exposure means and drawing means are provided around the drum or the plate cylinder. Thus, the exposure and the drawing in the heat mode can be performed only by rotating the drum or the plate cylinder, so that the apparatus can be configured to be compact and the space can be saved.

Further, by providing the plate making apparatus with an ink removing means for removing ink, the ink removing step can also be performed by the plate making apparatus, thereby simplifying the configuration of a printing system using the plate making apparatus according to the present invention. It can be.

In addition, the printing system according to the present invention has at least four printing devices,
Color printing can be performed by changing the color of the ink supplied in each printing device.

[0028]

Embodiments of the present invention will be described below with reference to the drawings.

According to the present invention, a material that changes from lipophilic to hydrophilic by a photocatalytic reaction, such as titanium oxide or zinc oxide, has the property of changing the hydrophilic / lipophilic properties of its surface upon irradiation with active light. Discovering that the changed surface properties return to their original properties due to heat, applying these phenomena to discrimination of ink receptivity and repulsion, and using that to create a printing master for offset printing, It is characterized by establishing a technology applied to the reproduction of used printing original plates.

FIG. 1 is a diagram showing the configuration of a printing system according to the first embodiment of the present invention. As shown in FIG. 1, a printing system according to a first embodiment of the present invention
And the printing device 2.

The plate making apparatus 1 includes an exposure drum 4 around which a plate-shaped original plate 3 mainly composed of a material that changes from lipophilic to hydrophilic by a photocatalytic reaction such as titanium oxide or zinc oxide is wound. The main body 7 includes an active light irradiating section 5 for performing overall exposure with active light and a thermal recording section 6 for performing heat mode drawing on the original 3 entirely exposed to active light. The main body 7 is provided with an original supply section 11 for supplying the original 3 into the main body 7 and an original discharge section 12 for discharging the original 3 from the main body 7 as described later.

The printing apparatus 2 includes a plate cylinder 15 around which the original plate 3 is wound, an ink / fountain solution supply unit 16 for supplying ink and dampening solution to the exposed surface exposed to the active light, and a plate cylinder after printing. The ink cleaning unit 17 for removing the ink remaining on the original 3 of the fifteen, the blanket 18 as an intermediate for transferring the ink held on the original 3 of the plate cylinder 15 to the paper, and the blanket 18 were fed. An impression cylinder 19 for holding a sheet is provided, and these members are accommodated in a main body 20. In addition, the main body 20 is provided with an original supply unit 21 for supplying the original 3 as described later.

It is well known that titanium oxide and zinc oxide provided on the master plate 3 have photosensitivity. In particular, in the case of zinc oxide, an electrostatic image can be obtained by irradiating light with charging or applying a voltage. This has been used as an electrofax in the field of electrostatography. However, the property that the hydrophilicity / lipophilic property of the surface is changed by irradiation with actinic light is a phenomenon newly found irrespective of the above-mentioned photoelectric charge generation, and the photosensitivity of titanium oxide and zinc oxide is changed. This was a phenomenon that was not noticed at the time when research was applied to the use of electrophotography in the field of electrophotography.

Furthermore, the idea of applying this change in surface properties to a plate making apparatus is a new technical idea.

As the photoreceptor of the present invention, any of titanium oxide and zinc oxide can be used, but titanium oxide is particularly preferred in view of sensitivity (ie, surface light change characteristics). As the titanium oxide, one produced by any known method such as sulfuric acid heating and baking of ilmenite or titanium slag, or heat chlorination and oxygen oxidation can be used. Alternatively, as described later, a method of forming an oxide film by a vacuum thin film forming method such as vacuum evaporation or sputtering at the printing plate preparation stage using titanium oxide itself or metal titanium can also be used.

To provide a layer containing titanium oxide (or zinc oxide) on the surface of the master 3, for example, (1) a dispersion of titanium oxide microcrystals (or zinc oxide microcrystals)
(2) a method of reducing or removing the binder by coating and baking, (3) a method of depositing titanium oxide (or zinc oxide) on the master 3, (4) a method of, for example, titanium butoxide. Any known method can be used, such as a method in which a titanium organic compound as described above is applied onto the master plate 3 and then subjected to hydrolysis and calcination oxidation to form a titanium oxide layer. In the present invention, a titanium oxide layer formed by vacuum deposition is particularly preferred.

The method of applying the titanium oxide microcrystals of the above (1) or (2) includes a method of applying a mixed dispersion of titanium oxide and silicon oxide to form a surface layer, a method of forming a titanium oxide and an organopolyoxide. There is a method of applying a mixture with siloxane or a monomer thereof. Further, it can be applied by dispersing in a polymer binder which can coexist with the oxide in the oxide layer. As the binder for the oxide fine particles, a polymer having dispersibility with respect to the titanium oxide fine particles can be widely used. Examples of preferred binder polymers include polyalkylene polymers such as polyethylene, polybutadienes, polyacrylates, polymethacrylates, polyvinyl acetate, polyvinyl formate, polyethylene terephthalate, polyethylene naphthalate, polyvinyl alcohol, and hydrophobic polymers such as polystyrene. These resins are preferably used, and these resins may be mixed.

In order to carry out the above-mentioned (3) vacuum deposition of titanium oxide, the inside of the vacuum deposition apparatus is usually vacuum degree exp (-5) To
After exhausting to rr or more, the oxygen gas pressure exp (-1 to-
6) When titanium oxide is evaporated by electron beam heating under Torr conditions, a deposited thin film of titanium oxide is formed on the deposition surface.

On the other hand, when a zinc oxide layer is used in the present invention, the zinc oxide layer can be formed by any known method. In particular, a method of forming an oxide film by electrolytic oxidation of the surface of a metal zinc plate and a method of forming a zinc oxide film by vacuum deposition are preferable.

The zinc oxide deposited film may be formed by depositing zinc oxide itself or metallic zinc in the presence of oxygen gas to form an oxide film in the same manner as the above-described titanium oxide deposition, or by forming a zinc metal film in the absence of oxygen. Is formed, the temperature may be raised to about 700 ° C. in air to oxidize.

The thickness of the deposited film is preferably 1 to 100,000 angstroms, and more preferably 10 to 10,000 angstroms, in any case of the titanium oxide layer and the zinc oxide layer. More preferably, the thickness is set to 3000 angstrom or less to prevent distortion of light interference. Further, it is convenient that the thickness is 50 Å or more in order to sufficiently exhibit the photoactivity.

As the titanium oxide, any crystal type can be used, but an anatase type is particularly preferred because of its high sensitivity. It is well known that anatase-type crystals can be obtained by selecting firing conditions in the process of firing titanium oxide. In this case, amorphous titanium oxide or rutile titanium oxide may coexist, but those containing 40% or more, preferably 60% or more of anatase type crystals are preferable for the above reason.

The volume ratio of titanium oxide or zinc oxide in the layer containing titanium oxide or zinc oxide as a main component is as follows:
Each is 30 to 100%, preferably 50% or more of oxide, and more preferably a continuous layer of oxide, that is, substantially 100%.

On the other hand, it is sometimes effective to dope a certain metal in order to enhance the property of changing the hydrophilicity of the surface by light irradiation. For this purpose, doping of a metal having a small ionization tendency is suitable. Yes, Pt, P
It is preferable to dope d, Au, Ag, Cu, Ni, Fe, and Co. Further, a plurality of these preferable metals may be doped.

On the other hand, if the volume ratio of titanium oxide or zinc oxide is low, the sensitivity of the surface of the layer to the change in hydrophilicity / lipophilicity decreases. Therefore, the volume fraction of oxide in the layer is
Desirably, it is 30% or more.

As the master 3 used in the present embodiment,
Various forms and materials can be used. For example, there is a method of directly providing an oxide layer by the above-described method such as vapor deposition, immersion or application of a titanium oxide layer on the surface of the original plate 3, and a method of providing a titanium oxide layer on the surface of a metal plate. In this case, as the metal plate, an aluminum plate, stainless steel,
A nickel or copper plate is preferable, and a flexible metal plate can be used. In addition, flexible plastic supports such as polyesters and cellulose esters can also be used. An oxide layer may be provided on a support such as waterproof paper, polyethylene laminated paper, or impregnated paper.

In the present invention, when a layer of titanium oxide (or zinc oxide) is provided on a support, the support used is a dimensionally stable plate-like material such as paper,
Paper laminated with plastic (eg, polyethylene, polypropylene, polystyrene, etc.), metal plate (eg, aluminum, zinc, copper, stainless steel, etc.), plastic film (eg, cellulose diacetate, cellulose triacetate, cellulose propionate, butyric acid) Cellulose, cellulose acetate butyrate, cellulose nitrate, polyethylene terephthalate, polyethylene, polystyrene, polypropylene, polycarbonate, polyvinyl acetal, etc.), paper on which the above-mentioned metal is laminated or vapor-deposited, or plastic film.

Preferred supports are polyester film, aluminum, or SU, which is less susceptible to corrosion on a printing plate.
Aluminum plates, which are S plates, of which dimensional stability is good and relatively inexpensive, are particularly preferred. Suitable aluminum plates are a pure aluminum plate and an alloy plate containing aluminum as a main component and a trace amount of a different element, and may be a plastic film on which aluminum is laminated or vapor-deposited. The foreign elements contained in the aluminum alloy include silicon, iron, manganese, copper, magnesium, chromium, zinc, bismuth, nickel, and titanium. The content of the foreign element in the alloy is at most 10% by weight or less. Aluminum which is particularly preferred in the present invention is pure aluminum, but completely pure aluminum is difficult to produce due to refining techniques, and therefore may contain slightly different elements. As described above, the composition of the aluminum plate applied to the present invention is not specified, and an aluminum plate of a conventionally known and used material can be appropriately used. The thickness of the support used in the present invention is about 0.0
5 mm to 0.6 mm, preferably 0.1 to 0.4 mm,
It is particularly preferably 0.15 mm to 0.3 mm.

Prior to roughening the aluminum plate, if necessary, a degreasing treatment is performed with a surfactant, an organic solvent or an alkaline aqueous solution for removing rolling oil on the surface.

The surface roughening treatment of the aluminum plate is performed by various methods. For example, a method of mechanically roughening the surface, a method of electrochemically dissolving and roughening the surface, and a method of chemically roughening the surface. Is selectively dissolved. As a mechanical method, a known method such as a ball polishing method, a brush polishing method, a blast polishing method, and a buff polishing method can be used. Further, as an electrochemical surface roughening method, there is a method of performing an alternating or direct current in a hydrochloric acid or nitric acid electrolyte. Further, a method combining both of them can be used as disclosed in JP-A-54-63902.

The aluminum plate thus roughened is subjected to an alkali etching treatment and a neutralization treatment, if necessary, and then subjected to an anodic oxidation treatment, if necessary, to increase the water retention and abrasion resistance of the surface. You. As the electrolyte used for the anodic oxidation treatment of the aluminum plate, various electrolytes that form a porous oxide film can be used, and generally, sulfuric acid, hydrochloric acid, nitric acid, chromic acid, or a mixed acid thereof is used. . The concentration of these electrolytes is appropriately determined depending on the type of the electrolyte.

The anodic oxidation treatment conditions vary depending on the electrolyte used and cannot be specified unconditionally. However, in general, the concentration of the electrolyte is 1 to 80% by weight, the solution temperature is 5 to 70 ° C., and the current density is 5 to 70%. It is appropriate that the range is 60 A / dm ² , the voltage is 1 to 100 V, and the electrolysis time is 10 seconds to 5 minutes.

When the amount of the anodic oxide film is less than 1.0 g / m ² , the printing durability is insufficient or the non-image area of the original 3 is easily scratched. The so-called "scratch dirt" to which is adhered easily occurs.

The master 3 having a surface layer of titanium oxide or zinc oxide is originally lipophilic and accepts ink.
The surface of the original 3 becomes hydrophilic by the entire surface light irradiation, so that ink is not accepted. After that, when drawing in the heat mode, for example, contact drawing of a heat medium or imagewise exposure with light that can be converted to heat energy, the drawn portion changes to lipophilic and has a property of receiving ink. become. Therefore, the printing plate 2 is contacted with the offset printing ink on the original plate 3 drawn in this way, the non-image area retains the dampening solution, and the image area forms a printing surface that has received the ink. Printing is performed by transferring the ink while bringing the printing surface into contact with the printing surface.

The "change between lipophilicity and hydrophilicity by light irradiation" which is the basis of the present invention is extremely remarkable. As the difference between the lipophilicity and the hydrophilicity between the image area and the non-image area increases, the discrimination effect becomes more remarkable, the printing surface becomes clearer, and the printing durability also increases. The difference between hydrophilicity and lipophilicity can be represented by a contact angle with a water droplet. As the hydrophilicity increases, the water droplets spread and the contact angle decreases,
Conversely, when water droplets are repelled (water repellency, that is, lipophilicity), the contact angle increases. That is, the printing original plate having the titanium oxide or zinc oxide surface layer of the present invention originally has a high contact angle with water, but the contact angle sharply decreases when irradiated with actinic light described below. However, since the ink changes to a property that repels lipophilic ink, an ink holding portion and a water holding portion are formed on the plate surface on the image, and the ink is transferred to the printing surface by contact with paper or the like.

Next, the actinic light irradiation section 5 of the plate making apparatus 1 will be described.

In the present invention, the entire surface of the master 3 is uniformly made hydrophilic by activating the active light prior to lipophilic image formation. As for the active light used for the whole surface exposure, a so-called surface exposure system that simultaneously irradiates the whole surface, a whole surface exposure system by moving light on a slit, or a scanning exposure system that scans a light beam over the whole surface May be. In the latter case, if the beam scanning interval is small enough not to substantially affect printing, it can be regarded as uniform whole-surface exposure. In general, if the light source is a laser light source, the beam scanning exposure method is advantageous, and if the light source is an incoherent divergent light source such as a light bulb or a discharge tube, the surface exposure method is advantageous.

In the present invention, the active light for exciting the thin layer containing titanium oxide or zinc oxide as the main component is light in the photosensitive region of the oxide. Titanium oxide has an anatase type of 387n
m or less, rutile type is 413 nm or less, zinc oxide is 387
Since it has a photosensitive region at nm or less, a mercury lamp, a tungsten halogen lamp, another metal halide lamp, a xenon lamp, or the like can be used. As the excitation light, a helium cadmium laser having an oscillation wavelength of 325 nm or a water-cooled argon laser having an oscillation wavelength of 351.1 to 363.8 nm can be used. Furthermore, in a gallium nitride laser system in which ultraviolet laser and near-ultraviolet laser oscillation has been confirmed, the oscillation wavelength is 360 to 360.
An InGaN-based quantum well semiconductor laser having a wavelength of 440 nm and a waveguide MgO-LiNbO ₃ inversion domain wavelength conversion device laser having an oscillation wavelength of 360 to 430 nm can be used.

In the case of zinc oxide, spectral sensitization may be carried out by a known method. In this case, the light source described above can be used.
Further, other than the above, for example, a tungsten lamp having a spectral distribution in the spectral sensitization region can be used.

The titanium oxide or zinc oxide on the surface layer is changed to hydrophilic by light absorption excitation according to the amount of irradiation, and when all of the titanium oxide or zinc oxide constituting the surface layer has been changed, further changes are made. Light irradiation does not change the degree of hydrophilicity.

The preferable amount of irradiation varies depending on the properties of the image forming layer of titanium oxide or zinc oxide, and since the contact angle decreases with the amount of irradiation, the ultraviolet light has a property that varies depending on the target level of image / non-image discrimination. There is
Normally, the surface exposure intensity before modulation in the printing image is 0.05 to 100 joule / c for both titanium oxide and zinc oxide.
m ² , preferably 0.05 to 10 joule / cm ² , more preferably 0.05 to 5 joule / cm ² .

The reciprocity law is approximately established for light irradiation. For example, the same effect is obtained regardless of whether exposure is performed at 10 mW / cm ² for 100 seconds or at 1 W / cm ² for 1 second. As a result, there is no restriction on the selection of the light source as long as the active light is emitted. This irradiation light amount is a light amount that does not hinder the scanning method using a laser or the surface exposure method using a divergent light source.

Next, the thermosensitive recording section 6 of the plate making apparatus 1 will be described.

In order to form an oleophilic image area on the original plate 3 whose entire surface is uniformly hydrophilized, the surface of the original plate 3 is imagewise heated by the thermosensitive recording section 6. FIG. 2 shows a detailed configuration of the heat-sensitive recording unit 6 as a means for heating like an image. As shown in FIG. 2, the thermal recording unit 6
A thermal head based on a thermal head 41 that draws in a heat mode in close contact with the surface of the original 3 and an image signal S input from an editing / layout W / S 40 that creates an image signal S representing an image to be printed. Driving 41 and original 3
And a thermal head drive section 42 for performing drawing in the heat mode on the surface of the head. The thermal head 41 has a plurality of fine heating elements extending in an array or a matrix in the direction of the rotation axis of the original 3, and performs drawing on the original 3 in a heat mode for each line or a plurality of lines.
When the original 3 is rotated by the exposure drum 4, drawing is performed on the surface of the original 3 in the heat mode. A portion of the original 3 where no drawing is performed is a hydrophilic non-image area, and a drawn portion is a non-image area. This is a lipophilic image area.

FIG. 3 shows another configuration of the thermal recording section 6. As shown in FIG. 3, a thermal recording unit 6 in another example includes an infrared laser light source 43 for emitting an infrared laser beam and irradiating the original 3, and an editing / layout for creating an image signal S representing an image to be printed. An infrared laser light source driving unit 4 for driving the infrared laser light source 43 to modulate the infrared laser light based on the image signal S input from the W / S 40 and performing drawing in the heat mode on the surface of the original 3
4 The light source 43 is configured to scan the original 3 by moving the emitted infrared laser light relative to the original 3 in the rotation axis direction of the original 3.
Is rotated, the surface of the original 3 is exposed to the modulated infrared laser light, the portion of the original 3 not irradiated with the infrared laser light is made a hydrophilic non-image area, and the infrared laser light is irradiated. The portion is set as an oleophilic image area, and drawing is performed in the heat mode.

Although the method of directly modulating the infrared laser has been described here, it goes without saying that the image can be similarly drawn by a combination of the infrared laser and an external modulation element such as an acousto-optic element.

In the present invention, the thermal recording section 6 includes not only a thermal head and an infrared laser, but also a light-to-heat conversion head (light-to-heat conversion head), a method of irradiating a heat ray through an image mask, and a method of irradiating a heat ray. Flash exposure or slit exposure through a transmissive image mask, high-illuminance short-time flash exposure by discharging electricity stored in a large-capacity capacitor at a time can also be used. In this case, the appropriate exposure is 0.05 to 10 joule
/ Cm ² , preferably 0.05 to 5 joule / cm ² .

The above-mentioned photosensitivity that causes a change from lipophilicity to hydrophilicity by light is based on zirconia ceramics disclosed in the prior art (Japanese Patent Laid-Open No. 9-16909).
No. 8). For example, the sensitivity is 7 W / μm for zirconia ceramic.
The laser light is described as ² laser light, and the pulse duration of the laser light is 100 nanoseconds, which is 70 joule / cm ² , which is about one order of magnitude lower than the sensitivity of the titanium oxide layer. Although the mechanism is not sufficiently elucidated, it is considered to be a photo-exfoliation reaction of lipophilic organic matter deposits, and is different from the photo-change mechanism of zirconia. However, zirconia also shows a change between lipophilicity and hydrophilicity due to light irradiation similarly to titanium oxide and zinc oxide, and thus zirconia can be used in the present invention.

After the heat mode exposure for image printing on the surface layer of titanium oxide or zinc oxide which has been rendered hydrophilic by the entire irradiation of the active light, the original plate 3 can be printed as it is without developing.

The exposed portion of the master 3 obtained as described above is sufficiently hydrophilic, but if desired, an aqueous solution, a rinsing solution containing a surfactant, etc., and an insensitive portion containing gum arabic and a starch derivative. It is post-treated with a lipophilic liquid. These processes can be used in combination as the post-process in the present embodiment.

As a method therefor, a method of applying to the original plate 3 with a sponge or absorbent cotton impregnated with a surface-regulating liquid or dipping the original plate 3 in a vat filled with the surface-regulating liquid, or using an automatic coater Application or the like is applied. Further, making the amount of the coating uniform with a squeegee or a squeegee roller after the coating gives more preferable results. In general, it is appropriate that the application amount of the surface conditioning liquid is 0.03 to 0.8 g / m ² (dry weight).

The original plate 3 thus treated is discharged from the plate making device 1 and wound around the plate cylinder 15 of the printing device 2, and supplied with ink and dampening water from an ink / fountain solution supply unit 16 to be hydrophilic. The fountain solution is retained in the non-image areas of the sex and the ink is retained in the lipophilic image areas. Then, when the ink is held on the original plate 3, the ink is sent to the offset printing step and printing is performed.

As described above, the printing system according to the present embodiment has many advantages, mainly simplicity, as compared with the ordinary known lithographic printing method. That is, as described above, the chemical treatment with the alkaline developer is unnecessary, and the wiping and brushing operations involved are not required, and the environmental load due to the discharge of the development waste liquid is not involved.

Next, the ink cleaning section 17 of the printing apparatus 2 will be described.

The original 3 after printing is applied to the ink cleaning unit 17.
At which the ink is washed. This washing is performed by washing off the ink adhering to the master 3 using a hydrophobic petroleum solvent. As the solvent, there are aromatic hydrocarbons such as kerosene and isoper as commercially available printing ink dissolving liquids, and in addition to these, benzol, toluene, xylol, acetone,
Methyl ethyl ketone and a mixed solvent thereof may be used.

The printing plate from which the ink has been washed away is prepared for the next printing unless exposed to high temperatures. This used original 3
The surface can be made hydrophilic by the entire surface exposure by the active light irradiating section 5 described above, and drawing in the heat mode can be repeated again to be used for printing again.

Although the number of reproducible times of the original 3 in this embodiment is not completely understood, it is at least 15 times.
It is more than the number of times, and it is considered that the printing plate is restricted by irremovable stains, scratches on the printing surface that cannot be repaired practically, and mechanical deformation (distortion) of the plate material.

Next, the operation of the first embodiment will be described.

First, the original plate 3 is supplied from the original plate supply section 11 of the plate making apparatus 1 into the main body 7 and wound around the exposure drum 4.
Next, active light is emitted from the active light irradiating section 5 and the original 3
The surface of the master 3 is changed from lipophilic to hydrophilic. Then, when the irradiation of the active light ends, the heat-sensitive recording unit 6 performs the drawing in the heat mode as described above. As a result, the area where the drawing is performed becomes the original image area having lipophilicity, and the area where the drawing is not performed is the non-image area having hydrophilicity.
When the drawing in the heat mode is completed, the original 3
Is removed from the exposure drum 4 and discharged from the original discharge unit 12.

The original 3 discharged from the original discharge section 12 is
The sheet is conveyed to the original supply section 21 of the printing apparatus 2 by a conveying means (not shown) or manually, and further supplied into the main body 20 of the printing apparatus 2 and wound around the plate cylinder 15. Original 3 is plate cylinder 15
The ink and dampening water are supplied to the master 3 from the ink / fountain solution supply unit 16. This allows
The ink is held in the lipophilic image area of the master 3 and the dampening solution is held in the hydrophilic non-image area without holding the ink.

Thereafter, a sheet is supplied between the blanket 18 and the impression cylinder 19 as shown by an arrow A, and the ink held on the original 3 is transferred to the sheet via the blanket 18 to perform offset printing. .

After the printing is completed, the ink remaining on the original 3 is removed by the ink washing unit 17, the original 3 is removed from the plate cylinder 15, and the original 3 is discharged from the original supply unit 21. The discharged master 3 is transported to the master supply unit 11 of the plate making apparatus 1 by a transport means (not shown) or manually, and is reused.

As described above, according to the printing system of the present invention, a printing screen can be formed on the original plate 3 only by activating the entire surface of the light and drawing in the heat mode. Offset printing in which the sharpness of the image is maintained. In addition, since the original plate 3 can be returned to the original state by washing the original plate 3 and exposing the entire surface to actinic light again, the original plate 3 can be used repeatedly, whereby the printed matter can be provided at low cost. Become.

Also, by wrapping the original 3 around the exposure drum 4 and arranging the active light irradiating section 5 and the thermal recording section 6 around the exposure drum 4, an image can be formed simply by rotating the exposure drum 4. Since heating and heating can be performed, the apparatus can be configured to be compact, thereby saving space.

Hereinafter, specific examples of the present invention will be described.

Copper was added to 99.5% by weight of aluminum in the presence of copper.
A 0.30 mm-thick rolled JIS Al050 aluminum sheet containing 01% by weight, 0.03% by weight of titanium, 0.3% by weight of iron, and 0.1% by weight of silicon was used as a 400 mesh pumice stone (manufactured by Kyoritsu Ceramics). ), And its surface was grained using a rotating nylon brush (6,10-nylon), and then thoroughly washed with water.

This was immersed in a 15% by weight aqueous sodium hydroxide solution (containing 4.5% by weight of aluminum) and etched so that the amount of aluminum dissolved was 5 g / m ² , and then washed with running water. Further, the mixture is neutralized with 1% by weight nitric acid, and then a 0.7% by weight nitric acid aqueous solution (aluminum 0.5%) is used.
Weight%), the voltage at the anode is 10.5 volts, and the voltage at the cathode is 9.3 volts.
90, was subjected to charge roughening treatment with 160 clones / dm ² of anode electricity charges with current waveform) disclosed in Japanese Example No. Sho 58-5796. After washing with water, the substrate was immersed in a 10% by weight aqueous solution of sodium hydroxide at 35 ° C., etched so that the amount of aluminum dissolved was 1 g / m ² , and then washed with water. Next, it was immersed in a 30% by weight aqueous sulfuric acid solution at 50 ° C., desmutted, and washed with water.

Further, a porous anodic oxide film forming treatment was performed in a 20% by weight aqueous sulfuric acid solution (containing 0.8% by weight of aluminum) at 35 ° C. using a direct current. That is,
Electrolysis was performed at a current density of 13 A / dm ² , and the anodic oxide film weight was adjusted to 2.7 g / m ² by adjusting the electrolysis time.

After washing the support, the support was immersed in a 3% by weight aqueous solution of sodium silicate at 70 ° C. for 30 seconds, washed with water and dried.

The aluminum support obtained as described above had a reflection density of 0.30 and a center line average roughness of 0.58 μm as measured by a Macbeth RD920 reflection densitometer.

Next, this aluminum support was placed in a vacuum evaporation apparatus, heated to 200 ° C., and heated to 1.0 × 10 ⁻⁸ T
orr, and oxygen gas pressure of 1.5 × 10 ^-4 To
The titanium oxide was heated by electron beam under the condition of rr to form a titanium oxide thin film on the aluminum support. The crystal component of this thin film was determined by X-ray analysis to have an amorphous / anatase / rutile crystal structure ratio of 2.5 / 4.5 / 3,
The thickness of the titanium oxide thin film was 750 angstroms. This was used as a sample of Master 3.

A light source device for USIO baking manufactured by Ushio Electric Co., Ltd., UNILEC URM-600 type GH-6
Using 0201X, light with a light intensity of 35 mW / cm ²
The entire surface of the original 3 was uniformly exposed for 15 seconds by slowly rotating the exposure drum 4 around which the original 3 was wound through a slit of 0 cm. The contact angle of the surface was measured by the air drop method using CONTACT-ANGLE METER CA-D manufactured by Kyowa Interface Science Co., Ltd. The contact angle to water (water drop in the air) was between 5 and 7 degrees in any part of the plate. Was.

Using a heating element array in which 150 μm × 150 μm thermal heads each having a sialon wear-resistant protective layer provided on a Ta—SiO ₂ heating resistor are arranged at 250 μm intervals, they are brought into contact with the titanium oxide surface layer to raise the temperature. Printing was performed. The temperature of the used thermal head reached 450 ° C. by energization for 20 msec, and it was confirmed by separately performing temperature measurement. The recording speed was 400 m / sec.

The original plate 3 thus obtained was used in a single-sided printing machine of Oliver 52 manufactured by Sakurai, the dampening water was pure water, and the ink was Newchampion F gloss 8 manufactured by Dainippon Ink and Chemicals, Inc.
Offset printing was performed on 1,000 sheets using five inks. A clear printed matter was obtained from the start to the end, and no damage to the master 3 was observed.

Next, the surface of the master plate 3 is coated with a printing ink cleaning liquid, Daiclean R (released by Dainippon Ink and Chemicals, Inc.).
To remove the ink.

Next, a light source device for baking USIO manufactured by USHIO INC. UNILEX URM-600 type GH-602
Light of 35 mW / cm ² using 10X
Exposure drum 4 with original 3 wound through slit
Was slowly rotated to uniformly expose the entire surface of the original 3 for 15 seconds.

Next, different drawing was performed on the surface of the original plate 3 by using a thermal head under the same conditions as described above.

The original plate 3 was used for a single-sided printing machine of Oliver 52 manufactured by Sakurai Co., Ltd., and the dampening solution was purified water using pure water, and the ink was prepared using Newchampion F gloss 85 ink manufactured by Dainippon Ink and Chemicals, Inc.
00 sheet offset printing was performed. A clear printed matter was obtained from the start to the end, and no damage to the master 3 was observed.

When the above-mentioned repetition was performed five times, no change was observed in the light sensitivity of the master plate 3, the sensitivity of thermal recording, the reproducibility of the contact angle, and the like.

From the above results, the original plate 3 having the titanium oxide heat-sensitive layer provided on the rolled plate support can be used not only for optical drawing in heat mode but also for direct electrothermal printing with a thermal head. It was shown that regeneration can be repeated only by washing and removing.

Next, a second embodiment of the present invention will be described.

FIG. 4 is a diagram showing the configuration of a printing system according to the second embodiment of the present invention. In the second embodiment, the same components as those of the first embodiment are denoted by the same reference numerals, and the detailed description is omitted. In the second embodiment, the plate making device 1 and the printing device 2 are the same unit 2
3 is different from that of the first embodiment in that a transport device 24 that transports the original plate 3 is provided between the plate making device 1 and the printing device 2.

Next, the operation of the second embodiment will be described.

First, the original plate 3 is supplied into the main body 7 from the original plate supply section 11 of the plate making apparatus 1 and the original plate 3 is wound around the exposure drum 4. Next, active light is emitted from the active light irradiating section 5 and irradiates the entire surface of the master 3, whereby the surface of the master 3 changes from lipophilic to hydrophilic. Then, when the irradiation of the active light ends, the heat-sensitive recording unit 6 performs the drawing in the heat mode as described above. As a result, the area where the drawing is performed becomes the original image area having lipophilicity, and the area where the drawing is not performed is the non-image area having hydrophilicity. When the drawing in the heat mode is completed, the original 3 is removed from the exposure drum 4 and transported to the printing device 2 by the transport device 24.

The original 3 conveyed to the printing device 2 is supplied into the main body 20 of the printing device 2 and wound around the plate cylinder 15. When the master 3 is wound around the plate cylinder 15, ink and dampening water are supplied to the master 3 from the ink / fountain solution supply unit 16. As a result, the ink is held in the lipophilic image area of the master 3, and the dampening solution is held in the hydrophilic non-image area without holding the ink.

Thereafter, a sheet is supplied between the blanket 18 and the impression cylinder 19 as shown by an arrow B, and the ink held on the master 3 is transferred to the sheet via the blanket 18 to perform offset printing. .

After printing is completed, the ink remaining on the original 3 is removed by the ink cleaning unit 17. Thereafter, the original plate 3 is removed from the plate cylinder 15 and transported by the transport device 24 to the plate making device 1 for reuse.

In the first and second embodiments, the ink cleaning section 17 is provided in the printing apparatus 2. However, the ink cleaning section 17 may be provided in the plate making apparatus 1. You may make it provide separately.

In the first and second embodiments, the original plate 3 is made detachable from the exposure drum 4, and the original plate 3 is conveyed between the plate making device 1 and the printing device 2 to perform offset printing. I try to do it, but the original 3
May be provided as a plate cylinder so as to be detachable from the plate making device 1 and the printing device 2, and the plate cylinder as the original plate 3 may be transported between the plate making device 1 and the printing device 2 to perform offset printing.

Further, in the first and second embodiments, the plate making apparatus in which the original 3 is wound around the exposure drum 4 to perform exposure and drawing in the heat mode has been described, but the original 3 is wound around the exposure drum 4. Instead, a plate making apparatus used in a flat plate shape may be used. Hereinafter, this plate making apparatus will be described as a third embodiment.

FIG. 5 is a diagram showing a configuration of a plate making apparatus used in a printing system according to the third embodiment of the present invention.
In the third embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description is omitted. In the third embodiment, the ink cleaning unit 1 provided in the printing device 2 in the first and second embodiments is used.
7 is provided in the plate making apparatus 1, and an ink washing unit 17, an active light irradiation unit 5, and a thermal recording unit 6 are arranged in series.

In FIG. 5, the ink cleaning section 17 has a roller 17A for wiping the ink and a discharge section 17B for discharging the cleaning liquid. The heat-sensitive recording unit 6 has a heat-sensitive head 6A for performing drawing on the original 3 in the heat mode.

Next, the operation of the third embodiment will be described. In addition, about the printing apparatus 2, the ink washing | cleaning part 1
Since the configuration is the same as the first and second embodiments except for 7, the description is omitted. The master 3 on which printing has been completed is conveyed to the plate making apparatus 1 as shown by an arrow C.
In 7, the remaining ink is removed, and then the entire surface is exposed to active light in the active light irradiation unit 5. As a result, the surface of the master 3 changes from lipophilic to hydrophilic. Then, when the irradiation of the active light ends, the heat-sensitive recording unit 6 performs the drawing in the heat mode as described above. As a result, the area where the drawing is performed becomes the original image area having lipophilicity, and the area where the drawing is not performed is the non-image area having hydrophilicity. When the drawing in the heat mode is completed, the original 3 is supplied to the printing device 2 and printing is performed.

As described above, even when the original plate 3 is used in a flat plate shape as in the third embodiment, a printing screen can be formed on the original plate 3 only by activating the entire surface of the substrate with light and drawing in the heat mode. This makes it possible to perform offset printing which does not require a developing surface and maintains the sharpness of the printing surface.
In addition, since the original plate 3 can be returned to the original state by washing the original plate 3 and exposing the entire surface to actinic light again, the original plate 3 can be used repeatedly, whereby the printed matter can be provided at low cost. Become.

In the third embodiment, drawing in the heat mode is performed by the heat-sensitive head 6A in the heat-sensitive recording unit 6. However, drawing may be performed by the infrared laser shown in FIG. Good.

Next, a fourth embodiment of the present invention will be described.

FIG. 6 is a diagram showing the configuration of a printing system according to the fourth embodiment of the present invention. In the printing system shown in FIG. 6, four plate making apparatuses 1 shown in FIG. 1 or FIG. 2 are arranged in series in the main body 32 as plate making units 1Y, 1M, 1C and 1B, and the printing apparatus 2 is made up of the plate making units 1Y and 1Y.
1M, 1C, 1B, and the printing units 2Y, 2M,
2C and 2B are arranged in the main body 32. In the corresponding units, color is applied using Y (yellow), M (magenta), C (cyan), and B (black) inks. This is for printing.

The construction and operation of each of the plate making units 1Y, 1M, 1C, 1B and each of the printing units 2Y, 2M, 2C, 2B are the same as those of the plate making device and the printing device shown in FIG. 1 or FIG. Detailed description is omitted.
In the fourth embodiment, each plate making unit 1Y, 1
In M, 1C and 1B, Y (yellow),
An original 3 on which images corresponding to the colors M (magenta), C (cyan) and B (black) are drawn in the heat mode is obtained, and ink and dampening water are supplied to the printing units 2Y, 2M, 2C and 2B. The difference is that the colors of the inks supplied in the sections are Y, M, C, and B, respectively.

Next, the operation of the fourth embodiment will be described.

First, each of the plate making units 1Y, 1M, 1C,
After the entire surface of the master 3 has been exposed by actinic light in 1B,
An image representing each color is drawn by the thermal recording unit. And
The original 3 on which the drawing in the heat mode has been performed is supplied to each of the printing units 2Y, 2M, 2C, and 2B.
Y, 2M, 2C, 2B, Y,
M, C, and B inks are supplied to hold the ink and the fountain solution in the original plate 3 of each of the printing units 2Y, 2M, 2C, and 2B. Thereafter, as shown by an arrow D in FIG. 6, the paper is supplied, and the printing units 2Y, 2M, 2C, 2
Transfer ink B to paper. That is, in the printing unit 2Y, the Y ink is transferred, and
In M, the M ink is transferred to the printing unit 2C.
In the above, the C ink is transferred, and in the printing unit 2B, the B ink is transferred. As a result, a color image is printed on the sheet.

After the printing is completed, each of the printing units 2Y, 2M,
The ink remaining on the master 3 is removed by the ink cleaning sections 2C and 2B. After that, the master 3 is transferred to each of the plate making units 1Y,
It is transported to 1M, 1C, and 1B and used for reuse.

In the fourth embodiment, the plate making units 1Y, 1M, 1C, and 1B are provided for each color to be printed. However, only one plate making unit is provided, and Y, An original 3 corresponding to each of the colors M, C, and B is created, and each printing unit 2Y, 2M, 2C, 2
B may be supplied. In this case, the original plate 3 from which printing has been completed and from which ink has been removed is sequentially supplied to one plate making unit and heated.

In the fourth embodiment, the plate making units 1Y, 1M, 1C and 1B are shown in FIG.
5 is used, but as shown in FIG. 5, a plate making apparatus for transporting an original plate 3 in a flat plate shape and performing full-surface exposure and drawing in a heat mode is used.
Y, 1M, 1C, and 1B may be provided.
When the plate making apparatus shown in FIG. 5 is used, it is not necessary to provide an ink cleaning unit in each of the printing units 2Y, 2M, 2C, 2B.

Next, a fifth embodiment of the present invention will be described.

FIG. 7 is a diagram showing a configuration of a printing system according to a fifth embodiment of the present invention, and FIG. 8 is an enlarged view of a main part of FIG. In the printing system shown in FIG. 7, the plate making apparatus 1 shown in FIG. 1 or 2 is arranged in the main body 33, and the printing apparatus is connected to the printing stations 34Y, 34M, 34C, 34B.
Are arranged around the impression cylinder 19 in the main body 33, and are respectively Y (yellow) and M
(Magenta), C (cyan), and B (black) inks are used for color printing.

Each printing station 34Y, 34M, 34
C, 34B have the same configuration,
FIG. 8 is representative of Y. As shown in FIG. 8, as in the first or second embodiment, the printing station 34Y applies ink and dampening solution to the exposed surface of the original 3 attached to the plate cylinder 15 after being exposed to active light. An ink / fountain solution supply unit 16 for supplying ink, an ink washing unit 17 for removing ink remaining on the original plate 3 after printing, and an impression cylinder as an intermediate for transferring the ink held on the original plate 3 to paper. A blanket 18 is provided for contacting the blanket 19.

The operations of the plate making apparatus 1 and the printing stations 34Y, 34M, 34C, 34B are described in FIG.
Alternatively, since the printing system is the same as the printing system shown in FIG. 2, detailed description will be omitted. In the fifth embodiment, in the plate making apparatus 1, Y (yellow), M (magenta), C
The drawing in the heat mode corresponding to each color of (cyan) and B (black) is sequentially performed on the original 3 corresponding to each color, and the printing stations 34Y, 34M, 34
The difference is that the colors of the inks supplied in the ink / fountain solution supply units C and 34B are Y, M, C and B, respectively.

Next, the operation of the fifth embodiment will be described.

First, after the original plate 3 corresponding to each of the colors Y, M, C, and B is entirely exposed to the active light in the plate making apparatus 1, images representing the respective colors are sequentially drawn by the thermosensitive recording section. Then, the original 3 on which the drawing in the heat mode is performed is sequentially supplied to each of the printing stations 34Y, 34M, 34C, and 34B, and each of the printing stations 34Y, 34M, and 34B.
From the ink / fountain solution supply unit 16 of C, 34B, Y, M,
The inks of the respective colors C and B are supplied to hold the ink and the fountain solution in the master plate 3 of each of the printing stations 34Y, 34M, 34C and 34B. Thereafter, a sheet is supplied as shown by an arrow E in FIG.
The C and 34B inks are transferred to paper. That is, in the printing station 34Y, the Y ink is transferred,
At the printing station 34M, the M ink is transferred, at the printing station 34C, the C ink is transferred, and at the printing station 34B, the B ink is transferred. As a result, a color image is printed on the sheet.

After the printing is completed, each of the printing units 2Y, 2M,
The ink remaining on the master 3 is removed by the ink cleaning sections 2C and 2B. As a result, the original plate 3 returns to the state before the active light is entirely exposed, and becomes a state where it can be repeatedly used. After that, the original plate 3 is transported to the plate making apparatus 1 and is reused.

In the fifth embodiment, the original plate 3 corresponding to each color is created in the plate making apparatus 1.
A plate-making apparatus 1 is provided corresponding to each color to be printed as a plate-making station, and Y, M, C,
The original 3 corresponding to each color B may be created and supplied to the printing stations 34Y, 34M, 34C, 34B.

In the fifth embodiment, the plate making apparatus 1 is the same as the plate making apparatus shown in FIG. 1 or FIG. 2, but the plate 3 is transported as shown in FIG. In addition, a plate making apparatus for performing the entire surface exposure and the drawing in the heat mode may be provided. In the case where the plate making apparatus shown in FIG.
In Y, 34M, 34C, and 34B, there is no need to provide an ink cleaning unit.

In the fourth and fifth embodiments, the four printing units 2Y, 2M, 2C, 2B or the four printing stations 34Y, 34M, 34
Although color printing is performed using C and 34B, five or more printing units or printing stations may be provided to perform color printing.

In the fourth and fifth embodiments, the offset printing is performed by transporting the original plate 3 between the plate making device (plate making unit) and the printing unit (printing station). The original plate 3 may be used as a plate cylinder, and the plate cylinder as the original plate 3 may be transported between a plate-making apparatus (plate-making unit) and a printing unit (printing station) to perform offset printing.

Further, in the fourth and fifth embodiments, the ink washing section is provided in the printing unit (printing station), but may be provided in the plate making apparatus (plate making unit). Unit) and the printing unit (printing station) may be provided separately.

In the first to fifth embodiments, titanium oxide and zinc oxide are used as materials that change from lipophilic to hydrophilic by a photocatalytic reaction. However, the present invention is not limited to this. Instead, any material can be used as long as the material changes from lipophilic to hydrophilic by a photocatalytic reaction.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a printing system according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a detailed configuration of a thermal recording unit.

FIG. 3 is a diagram showing a detailed configuration of a thermal recording unit.

FIG. 4 is a diagram showing a configuration of a printing system according to a second embodiment of the present invention.

FIG. 5 is a diagram showing a configuration of a plate making apparatus according to a third embodiment of the present invention.

FIG. 6 is a diagram showing a configuration of a printing system according to a fourth embodiment of the present invention.

FIG. 7 is a diagram showing a configuration of a printing system according to a fifth embodiment of the present invention.

8 is an enlarged view of a main part of FIG. 7;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Plate-making apparatus 1Y, 1M, 1C, 1B Plate-making unit 2 Printing apparatus 2Y, 2M, 2C, 2B Printing unit 3 Master 4 Exposure drum 5 Active light irradiation part 5A Light source 6 Thermal recording part 6A Thermal head 7, 20, 32, 33 Main body 11 Original plate supply unit 12 Original plate discharge unit 15 Plate cylinder 16 Ink / fountain solution supply unit 17 Ink washing unit 17A Roller 17B Discharge unit 18 Blanket 19 Impression cylinder 24 Transport device 34Y, 34M, 34C, 34B Printing station 40 Editing / layout W / S 41 Thermal head 42 Thermal head drive unit 43 Infrared laser light source 44 Infrared laser light source drive unit S Image signal

Claims (11)

[Claims] 1. A printing original plate having a thin film mainly composed of a material which changes from lipophilic to hydrophilic by a photocatalytic reaction on its surface, and is detachably provided. A plate making apparatus comprising: an exposing unit for performing exposure; and a drawing unit for performing drawing in a heat mode on the printing original plate that has been entirely exposed by the exposing unit. 2. The printing master comprises a plate-shaped master detachably provided on the surface of a drum, wherein the exposing means and the drawing means are arranged around the drum. The plate making apparatus according to claim 1, wherein 3. The plate making apparatus according to claim 1, wherein the printing original plate comprises a plate cylinder, and the exposure means and the drawing means are arranged around the plate cylinder. 4. The plate making apparatus according to claim 1, wherein said drawing means comprises a thermal head. 5. A plate making apparatus according to claim 1, wherein said drawing means comprises a laser. 6. The plate making apparatus according to claim 1, wherein the material that changes from lipophilic to hydrophilic by the photocatalytic reaction is made of titanium oxide or zinc oxide. 7. The plate making apparatus according to claim 1, further comprising an ink removing unit that removes ink remaining on the printing original after printing is completed. 8. The plate-making apparatus according to claim 1, a holding unit for detachably holding the printing original plate removed from the plate-making apparatus, and the heat-mode drawing. A printing apparatus provided with ink supply means for supplying ink to the printing plate to form an image area on the printing plate; and an ink removing unit for removing ink remaining on the printing plate after printing is completed. A printing system, characterized in that: 9. The printing system according to claim 8, wherein said ink removing means is provided in said printing apparatus. 10. The printing system according to claim 8, wherein said ink removing means is provided in said plate making device. 11. The printing system according to claim 8, comprising at least four printing devices.