JP2000203143A - Offset printing method and printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To incorporate a printing image quality of a practical level having high identifiability between an image part and a non-image part of a printed surface and to repeatedly use a master for printing by simply engraving without necessity of an alkaline developer. SOLUTION: The offset printing method comprises the steps of heating a master for printing constituted of one substance having a specific heat responsive characteristics such as a titanium oxide, a zinc oxide or the like on a surface to a hydrophilic developing temperature (200 deg.C or above) to make the surface hydrophilic, then drawing an image in a heat mode at a hydrophobic developing temperature (50 to 250 deg.C) to form a hydrophobic image area, and receiving a printing ink on the area. The printer for the method is provided. Further, a method for reusing the master comprises the steps of cleaning and removing the ink retaining on a printed surface of the printing plate, and then repeating the above-described operation by using the master.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to the field of general light printing,
In particular, the present invention relates to offset printing, and more particularly to a novel offset printing method and a printing original plate capable of easily producing a printing plate. In particular, the present invention relates to an offset printing method which enables repeated use of a printing plate, a printing plate, and a printing apparatus using the same.

[0002]

2. Description of the Related Art The offset printing method has been used particularly commonly because of a simple printing plate manufacturing process among many printing methods, and is the main printing method at present. This printing technique is based on the immiscibility of oil and water, with the image areas selectively retaining oily material or ink and the non-image areas selectively retaining fountain solution. Therefore, when the surface to be printed 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 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 surface of the aluminum substrate, which is the support, is subjected to graining, anodic oxidation, and other treatments to enhance the ink receptivity of the image area and the ink repellency of the non-image area, thereby improving the printing durability. Then, the printing surface is refined, and an image for printing is formed on the surface. Therefore, offset printing has been provided with characteristics such as printing durability and high definition of a printing surface in addition to simplicity.

[0004] While the use of the offset printing method has been widespread and spread in the general printing field due to high definition, further simplification of the offset printing method has been demanded, and many simple printing methods have been proposed.

[0005] Representative examples thereof include a Copyrapid offset printing plate commercially available from Agfa-Gevaert, and US Pat.
No. 11656, a printing method based on the preparation of a printing plate by a silver salt diffusion transfer method disclosed in Japanese Patent Application Laid-Open No. 7-56351 and the like. Since the image is lipophilic and can be directly used as a printing plate, it is practically used as a simple printing method. However, although simple, this method also requires a diffusion transfer development step using an alkaline developer. There is a demand for a simple printing method that does not require a developing step with a developer.

[0006] The development of a method for manufacturing a simple printing plate in which the developing step using an alkali developing solution after image exposure has been performed has been developed from the above background. In the technical field of this simple printing plate, which is also called an unprocessed printing plate because the development step can be omitted, the image formation by thermal destruction of the irradiated portion on the image recording surface mainly by imagewise exposure, Image formation by lipophilicity and lipophilicity of the irradiated part are also based on various principles such as photo-mode curing, changes in surface properties due to photolysis of diazo compounds, and heat mode fusion thermal transfer of image areas. Proposed.

The technique disclosed as the above simple offset printing method 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, 731,317 and 5,23
No. 8,778, No. 5,353,705, No. 5,3
U.S. Patents Nos. 85,092 and 5,395,729 and European Patent 1068.

[0008] These are designed so as not to require a developing solution at the time of plate making. However, the difference between the lipophilic region and the hydrophilic region is insufficient, so that the image quality of the printed image is inferior and the resolution is poor. Inferior, difficult to obtain a printed screen with excellent sharpness, insufficient mechanical strength of the image surface, and easy to be scratched. This is accompanied by at least one of the drawbacks, such as insufficient durability to withstand, and shows that simply eliminating the alkali development step does not involve practicality. In spite of the above-mentioned many improvements, a strong demand for a printing plate preparation method that has various characteristics required for printing and can easily produce a printing plate has not been sufficiently satisfied.

As one of the above-mentioned methods for preparing a non-processable printing plate, there is disclosed a printing plate manufacturing method utilizing the fact that zirconia ceramics become hydrophilic by light irradiation.
No. However, the light sensitivity of zirconia is insufficient, and the effect of converting light from hydrophobic to hydrophilic is insufficient, so that the discriminability between the image area and the non-image area is insufficient.

If there is a simple printing method that 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. For recycling of original printing plates,
The simplicity of the reproduction operation affects the practical value, but the simplification of the reproduction operation is a difficult task, and has been hardly studied in the past, and is slightly referred to as zirconia ceramic in JP-A-9-169098. It only discloses a special raw material.

[0011]

SUMMARY OF THE INVENTION In view of the above circumstances, it is an object of the present invention to eliminate the need for an alkaline developer, to make a plate easily, and to discriminate an image area and a non-image area on a printing surface. It is an object of the present invention to provide an offset printing method which has high print quality, has a practical level of print quality, and is capable of repeatedly using a printing plate. A second object of the present invention is to provide a printing apparatus capable of performing printing at a practical level of print quality by a simple operation using the above-described printing method and repeatedly using a printing original plate.

[0012]

Means for Solving the Problems The present inventors have conducted intensive studies in order to achieve the above object, and as a result, it has been found that the surface of certain metal oxides and metals has a hydrophobic property due to the action of heat. The degree of hydrophilicity is changed, and it is recognized that the change has a property that can be changed in any direction of hydrophobicity and hydrophilicity depending on heating conditions, and this property is considered as the formation of a printing image on a plate surface and It has been found that the above-mentioned problem can be solved by using the image on the printing plate after erasing the printing, and the present invention has been completed based on this possibility. That is, the present invention is as follows.

1. The surface of the printing plate is made hydrophilic by heating the plate at a high hydrophilicity developing temperature, and then a hydrophobic image area is formed by applying heat mode drawing to the original plate at a hydrophobicity developing temperature. A printing surface in which an image area accepts the ink by contacting the ink with a printing ink to perform printing.

2. 2. The offset printing method according to claim 1, wherein the high-temperature hydrophilicity developing temperature is 200 ° C. or higher, and the hydrophobicity developing temperature is 50 to 250 ° C. and lower than the high-temperature hydrophilicity developing temperature.

[0015] 3. The method according to the above item 1 or 2, wherein after the ink remaining on the printing plate surface used for printing is removed by washing, the operation described in the above item 1 or 2 is repeated using the printing plate. Printing method.

4. The surface of the printing plate is the third in the periodic table
Wherein the metal oxide and the metal oxide are selected from elements other than group 0 and VIIA (halogen element), and are composed of at least one of oxides of the metal. The offset printing method according to any one of the above items.

5. The surface of the printing plate is TiO ₂ , RT
iO ₃ (R is an alkaline earth metal atom), AB _2-x C _x D
_3-x E _x O ₁₀ (A is a hydrogen atom or an alkali metal atom, B
Is an alkaline earth metal atom or a lead atom, C is a rare earth atom,
D is a metal atom belonging to a group 5A element of the periodic table, E is a metal atom also belonging to a group 4A element, and x represents any numerical value from 0 to 2), SnO ₂ , Bi ₂ O ₃ , SiO ₂ , GeO
_2, Al ₂ O _3, an offset printing method according to any one of the above 1 to 4, characterized in that it is constituted by at least one metal oxide selected from ZnO and Fe ₂ O _3.

6. The surface of the printing plate is aluminum,
The offset printing method according to any one of the above items 1 to 5, wherein the offset printing method is constituted by at least one of a metal or a metal alloy selected from iron, copper, silicon, nickel, germanium, zinc and tin.

[7] Wherein the drawing in the heat mode is performed by one of drawing means selected from a thermal transfer recording head and light-to-heat conversion type radiation.
7. The offset printing method according to any one of 6.

[8] (1) The heating temperature for hydrophilizing the surface of the printing original plate is 300 to 700 ° C.
8. The offset printing method according to any one of items 1 to 7, 9. The heat-mode drawing performed on the hydrophilic printing plate is performed in the presence of an organic compound.
The offset printing method according to any one of Items 1 to 8, above.

10. When the organic compound to be present in the drawing in the heat mode is at least one at 400 ° C.
10. The offset printing method according to claim 9, wherein the organic compound has a vapor pressure of not less than mmHg and is stable at a high temperature at which hydrophilicity is exhibited.

11. The offset according to claim 9 or 10, wherein the organic compound to be present in the drawing in the heat mode is an organic compound having a boiling point in the range of 30 to 400 ° C and being stable at a high hydrophilicity developing temperature. Printing method.

12. An offset printing apparatus used in the method according to any one of the above items 1 to 11, wherein an original plate mounting portion for mounting an original plate for printing, and a surface of the original plate heated to a high-temperature hydrophilic expression temperature by heating the original plate. Heating means for making hydrophilic,
A drawing unit for forming a hydrophobic image area by applying heat mode drawing to the original plate at a hydrophobic development temperature, and supplying a printing ink to the image area to form a printing surface in which the image area has received the ink; An offset printing apparatus comprising: an ink supply unit; and a printing unit that performs printing by bringing the printing surface into contact with a surface to be printed.

13. 13. The offset printing apparatus as described in 12 above, further comprising means for removing ink remaining on the printing plate after printing is completed.

14. 13. The offset printing apparatus according to the above item 12 or 12, wherein at least the exposing means, the drawing means, the ink supply means and the ink removing means are arranged around the plate cylinder.

15. The printing plate comprises a part of the plate cylinder, and at least the exposing means, the drawing means, the ink supply means and the ink removing means are arranged around the plate cylinder. The offset printing apparatus according to any one of claims 1 to 4.

The present invention has been made based on the discovery of a unique thermal change behavior of the surface properties of a specific substance (mainly, the above-mentioned metal oxides and metals). That is, the clean surface of this specific substance is inherently hydrophilic, but changes to hydrophobic when heated at an appropriate temperature (hereinafter referred to as “hydrophobic expression temperature”). ,
It is based on the discovery that it becomes hydrophilic again when heated to "hot hydrophilicity onset temperature" and that changes in these surface properties have a hysteretic effect.

If this property is utilized, the surface of the substance is made hydrophilic by heating at a high temperature at a hydrophilicity development temperature as a first step, and then the surface is imagewise converted to a hydrophobicity development temperature at a second step. To form an image of the hydrophobic region by heating in the above manner, and then, as a third step, offset printing can be performed by holding the printing ink in the hydrophobic region and the dampening water in the hydrophilic region. Further, after the printing is completed, the used printing plate is washed and removed of ink, and when the plate is heated again to the hydrophilic expression temperature, the printed image is erased. Can be used again. Needless to say, between the above-mentioned heating at the first stage of the hydrophilic expression temperature and the second stage of the heating at the hydrophobic expression temperature, the surface of this substance is subjected to the hydrophobic expression temperature by natural cooling or forced cooling. It is necessary to lower it below. The above-mentioned substance applied to the present invention has a hysteresis effect, and the surface once hydrophilized at a high hydrophilicity developing temperature is cooled without changing to hydrophobicity even after passing through a hydrophobicity developing temperature region in a cooling process. You. When the hydrophilic surface cooled to below the hydrophobic development temperature region is heated again to the hydrophobic development temperature, it becomes hydrophobic. Moreover, the hydrophobic image area on the original obtained by the heat mode drawing is stably maintained even at room temperature by the hysteresis effect. In the following description, the above-mentioned substance having the property of and against heat is referred to as “thermo-responsive substance”. The above-mentioned thermally responsive materials are often found in metals and metal oxides, and these metals and metal oxides are referred to as “thermally responsive metals” and “thermally responsive metal oxides,” respectively. I do. The heat-responsive substance and its unique heat-responsive behavior will be described later in detail.

[0029]

Embodiments of the present invention will be described below in detail. First, the “thermoresponsive substance” used in the present invention will be described. The heat-responsive substance is as described above,
The substance is defined as a substance having the properties of and, but this property is found in many metals and metal oxides, including those used as functional materials such as ceramics and semiconductors. . Thermally responsive ceramics are composed of composite metal oxides, and most of thermally responsive semiconductors are genuine semiconductors, such as silicon and germanium, whose bases and conductors are close to each other, and vanadium oxide and copper oxide, which depend on impurity levels. And found in both pseudo semiconductors. Since these ceramics and semiconductors are similar to other metal oxides and metals in terms of the thermal response characteristics of the substances used in the present invention, they are referred to as “thermoresponsive metal oxides” and “thermoresponsive metals”. And will be described below in that order.

It has the property of becoming hydrophobic by the above-mentioned moderate heating and becoming hydrophilic by further heating,
Metals and metal oxides that can be used as heat-responsive metal oxides that exhibit a hysteresis phenomenon are in various forms, including single metals and metal oxides, alloys and composite oxides. In the latter case, a solid solution, a mixed crystal, a polycrystal, an amorphous solid solution, and a mixture of metal oxide microcrystals have the above characteristics.
A metal oxide having such characteristics is empirically found in a metal of an element belonging to the third to sixth periods excluding groups 0 and VIIA (halogen element) of the periodic table and an oxide of the metal.
Since these metals and metal oxides must not be excessively dissolved in fountain solution when used as a printing plate, the solubility in water is 10 to 100 ml of water.
mg or less, preferably 5 mg or less, more preferably 1 m
g or less.

First, titanium oxide and zinc oxide will be described as preferred compounds among the “thermoresponsive metal oxides”. Any of them can be used in the present invention as a printing plate material having thermal responsiveness, but titanium oxide is particularly preferred in terms of sensitivity (that is, light change characteristics of surface properties). Titanium oxide is
It is possible to use ilmenite or titanium slag produced by any known method such as sulfuric acid heating and firing, or heat chlorination and oxygen oxidation. Alternatively, as described later, a method of forming an oxide film by vacuum evaporation in a printing plate manufacturing stage using titanium metal can also be used.

In order to provide a layer containing titanium oxide or zinc oxide on the surface of the original plate, for example, a method of applying a dispersion of titanium oxide microcrystals or zinc oxide microcrystals on a printing plate original plate is applied. A method of reducing or removing the binder by baking afterwards, a method of providing a titanium oxide (or zinc oxide) film on the printing original plate by a method such as vapor deposition, sputtering, CVD, or ion plating, for example, a titanium organic compound such as titanium butoxide Can be applied to the original plate and then subjected to firing oxidation to form a titanium oxide layer, or any other known method. In the present invention, a titanium oxide layer formed by vacuum evaporation or sputtering is particularly preferred.

The above or the method of applying the titanium oxide microcrystals is, specifically, a method of applying an amorphous titanium oxide microcrystal dispersion, followed by firing to form an anatase or rutile type titanium oxide layer. A method of applying a mixed dispersion of titanium oxide and silicon oxide to form a surface layer, and a method of applying a mixture of titanium oxide and organosiloxane to obtain a titanium oxide layer bonded to a support through a siloxane bond There is a method of dispersing and applying a polymer binder coexisting with an oxide in an oxide layer, followed by baking to remove an organic component. As the binder for the oxide fine particles, a polymer having dispersibility with respect to the titanium oxide fine particles and capable of being removed by firing at a relatively low temperature can be used. Examples of preferred binders include polyalkylene such as polyethylene, polybutadiene, polyacrylate, polymethacrylate, polyvinyl acetate, polyvinyl formate, polyethylene terephthalate,
Hydrophobic binders such as polyethylene naphthalate, polyvinyl alcohol, partially saponified polyvinyl alcohol, and polystyrene are preferred, and these resins may be used as a mixture.

In order to perform the above-described vacuum deposition of titanium oxide, usually, metal titanium is placed as a heat source for heating for vapor deposition in a vacuum vapor deposition apparatus, and the total gas pressure is 1 at a degree of vacuum of 10 ⁻⁸ to 10 ⁻⁵ Torr.
When the titanium metal is evaporated while keeping the oxygen partial pressure ratio at 0 ^-5 to 10 ^-2 Torr and the oxygen partial pressure ratio at 5 to 90%, a deposited thin film of titanium oxide is formed on the deposited surface. In the case of sputtering, for example, a titanium metal target is set in a sputtering apparatus and the Ar / O ₂ ratio is 60/40.
(Molar ratio), the gas pressure was adjusted to 5 × 10 ⁻³ Torr, and RF power of 200 W was applied to perform sputtering to form a titanium oxide thin film on the substrate.

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, the method of electrolytically oxidizing the surface of a metal zinc plate to form an oxide film, vacuum deposition, sputtering, CV
D, a method of forming a zinc oxide film by ion plating or the like is preferable. A method of forming an oxide film by depositing metal zinc in the presence of oxygen gas in the same manner as the above-described deposition of titanium oxide, or a method of forming a zinc metal film in the absence of oxygen, In the temperature of about 70
A method of raising the temperature to 0 ° C and oxidizing can be used. In addition, it can be obtained by heating a coated layer of zinc oxalate or a thin layer of zinc selenide in an oxidizing gas stream.

The thickness of the deposited film is preferably from 1 to 100,000 angstroms, and more preferably from 10 to 10,000 angstroms, for both the titanium oxide layer and the zinc oxide layer. More preferably, the thickness is set to 3000 angstroms 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 photoactivation effect.

As the titanium oxide, any crystalline form can be used, but 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-type 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 mainly containing titanium oxide or zinc oxide is 30 to 100%, preferably 50 to 100%.
% Or more is preferably occupied by the oxide, more preferably a continuous layer of oxide, ie substantially 100%.
However, since the surface hydrophilicity / lipophilicity change characteristics are not affected by the remarkable purity as when zinc oxide is used in the electrophotographic photosensitive layer, a material having a purity close to 100% (for example, 98%) is further purified. There is no need to convert. That is, it can be understood from the fact that the physical properties used in the present invention are the properties of changing the hydrophilic / lipophilic properties of the membrane surface, which are not related to the conductivity, that is, the properties of changing the properties of the interface.

However, it is sometimes effective to dope a certain metal in order to enhance the property of changing the hydrophilicity of the surface by the action of heat. For this purpose, doping with a metal having a low ionization tendency is suitable. And
It is preferable to dope Pt, Pd, Au, Ag, Cu, Ni, Fe, Co or Cr. Further, a plurality of these preferable metals may be doped. Also in the case where doping is performed, the injection amount is 5 mol% or less based on the metal components in zinc oxide and titanium oxide.

On the other hand, when the volume ratio is low, the hydrophilicity /
The sensitivity of the lipophilic thermal response behavior decreases. Therefore,
The volume ratio of the oxide in the layer is desirably 30% or more, particularly preferably substantially 100%.

The metal titanate represented by the general formula of RTiO ₃ is a compound preferably applicable to the present invention, and this compound will be described below. In the general formula RTiO ₃ , R represents magnesium, calcium, strontium,
It is a metal atom belonging to the alkaline earth element of the periodic table such as barium and beryllium, and strontium and barium are particularly preferable. In addition, two or more alkaline earth metal atoms can coexist as long as the total thereof is stoichiometrically consistent with the above formula.

Next, the general formula AB _2-x C _x D _3-x E _x O ₁₀
The compound represented by is described. In the general formula, A is a monovalent atom selected from a hydrogen atom and an alkali metal atom such as sodium, potassium, rubidium, cesium, and lithium. More than one species may coexist. B
Is an alkaline earth metal atom or a lead atom as defined above for R, and two or more kinds of atoms may coexist as long as they are stoichiometrically matched. C is a rare earth atom, preferably scandium and yttrium, and atoms belonging to lanthanide elements such as lanthanum, cerium, praseodymium, neodymium, holmium, europium, gadolinium, terbium, thulium, ytterbium, and lutetium. May coexist as long as stoichiometrically matches the above formula. D is one or more elements selected from Group 5A elements of the periodic table, and includes vanadium, niobium, and tantalum. Further, as long as the stoichiometric relationship is satisfied, two or more kinds of 5A group metal atoms may coexist. E is a metal atom belonging to a Group 4A element such as titanium, zirconium, or hafnium, and two or more kinds of Group 4A metal atoms may coexist. x represents an arbitrary numerical value of 0 to 2.

RTiO ₃ or the general formula AB _2-x C _x D _3-x E
also providing the compounds represented by _x O ₁₀ on the surface of the original plate, it is preferable to use the method of providing a titanium oxide and zinc oxide. That is, a method of applying a dispersion of the heat-responsive metal oxide fine particles on a printing plate original,
A method of reducing or removing the binder by coating and baking, a method of forming a film of the above oxide on the original plate of the printing plate by various vacuum thin film methods, for example, an organic compound such as a metal element alcoholate is formed on the original plate. After being applied to, a known arbitrary method such as a method of subjecting to hydrolysis and further calcination and oxidation to form a metal thin film of an appropriate thickness, a method of heating and spraying an aqueous solution of a hydrochloride or a nitrate containing the above-mentioned metal, or the like is used. be able to.

For example, in order to apply the barium titanate fine particles by the above-mentioned application method, a method of applying a mixed dispersion of barium titanate and silicon to form a surface layer, barium titanate and organopolysiloxane Alternatively, there is a method of applying a mixture with the monomer. Further, as described in the section of titanium oxide, the oxide layer can be formed by dispersing and applying a polymer binder which can coexist with the oxide in the oxide layer, followed by firing. Examples of the preferable polymer as the binder for the oxide fine particles are the same as those described in the section of the titanium oxide layer. In this method, in addition to barium titanate, magnesium titanate, calcium titanate, strontium titanate, or an intermolecular compound or mixture thereof can be similarly formed into a thin film.

Similarly, according to the above coating method,
CsLa_TwoNbTi_TwoO_TenFine particles can be applied
It is. CsLa_TwoNbTi_TwoO_TenThe fine particles, their chemical
Cs corresponding to stoichiometry_TwoCO_Three, La_TwoO_Three, NbO_Five,
TiO_TwoPulverize in a mortar, put in a platinum crucible, 13
Bake at 0 ° C for 5 hours, cool it and put it in a mortar
To fine particles of several microns or less. This CsLa_Two
NbTi_TwoO_TenFine particles similar to the above barium titanate
Was dispersed in a binder and applied to form a thin film.
This method uses CsLa_TwoNbTi_TwoO_TenLimited to fine particles
Without, HCa_1.5La_0.5Nb_2.5Ti_0.5O_Ten, HLa
_TwoNbTi_TwoO_TenAB mentioned above_2-xC _xD_3-xE_xO
_Ten, (0 ≦ x ≦ 2).

As a method for forming the thermally responsive metal oxide layer using the above-described vacuum thin film forming method, a sputtering method or a vacuum thin film forming method is generally used. In the sputtering method, a single or composite oxide target is prepared in advance. For example, a barium titanate crystal thin film can be obtained by performing RF sputtering in an argon / oxygen mixed atmosphere while maintaining the temperature of the support for the deposited film at 450 ° C. or higher using a barium titanate target. For controlling the crystallinity, post-annealing may be performed at 300 to 900 ° C. as necessary. This method can form a thin film on the above-mentioned RTiO ₃ (R is an alkaline earth metal atom) and other heat-responsive metal oxides by adjusting the substrate temperature optimal for crystal control in the same way. is there.
For example, when providing a tin oxide thin film, the substrate temperature is 120 ° C.
By performing RF sputtering in an argon / oxygen mixed atmosphere, a thin film of a tin oxide crystal for the purpose is obtained.

The above method using a metal alcoholate is also a method capable of forming a desired thin film without using a binder. To form a thin film of barium titanate, a mixed alcohol solution of barium ethoxide and titanium butoxide is applied on a silicon substrate having SiO ₂ on its surface, and the surface is hydrolyzed. It is possible to form a thin film of barium acid. Other RTiO ₃ which method was also described above in the scheme (R is an alkaline earth metal _{atom), AB 2-x C x} D 3-x E x O
₁₀ (A, B, C, D and E respectively represent the contents of the above definition), SnO ₂ , SiO ₂ , Bi ₂ O ₃ , SeO ₂ ,
It can be applied to the formation of thin films of GeO ₂ , Al ₂ O ₃ and Fe ₂ O ₃ .

Gold which exhibits a thermoresponsive function as described above
The method of forming a metal oxide thin film also does not include a binder.
It is possible to form a thin film of a system. SnO_TwoForm a thin film of
To do it, SnCl_FourHeat the aqueous hydrochloric acid solution above 200 ° C
Sprays on quartz or crystalline glass surfaces to form thin films
can do. This method uses SnO_TwoIn addition to thin film
RTiO mentioned_Three(R is an alkaline earth metal atom), AB
_2-xC_xD_3-xE_xO _Ten(A, B, C, D, E are each
Represents the content of the above definition), SiO_Two, Bi _TwoO_Three,
SeO_Two, GeO_Two, Al_TwoO_ThreeAnd Fe_TwoO_ThreeNozomi
It can also be applied to the formation of these thin films.

In any of the above cases, the thickness of the metal oxide thin film is preferably from 1 to 100,000 angstroms, and more preferably from 10 to 10,000 angstroms. More preferably, the thickness is set to 3000 angstroms 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 photoactivation effect.

In the thin layer of the above-mentioned thermoresponsive metal oxide when a binder is used, the volume ratio of the metal oxide is 50%.
It is preferable that the oxide occupy 90% or more, more preferably 90% or more, and more preferably a continuous layer of the oxide, that is, substantially 100%. This concludes the description of the “thermally responsive metal oxide” and the method of providing the same on the surface of the original plate. Next, the “thermally responsive metal oxide” will be described.

The metal which can be used as the heat-responsive metal has a property that it becomes hydrophobic by the above-mentioned appropriate heating, becomes hydrophilic when further heated, and exhibits a hysteresis phenomenon. Any metal may be used. A metal having such properties is empirically determined to be a group VII and a VII of the periodic table.
It is found in metal elements belonging to the third to sixth periods except for the group A (halogen element). Further, a metal having a thermal response characteristic found among the metals in the above range of the periodic table,
Either single composition metals or composite compositions or alloys can be used in the present invention. In the case of an alloy, any of a metal solid solution, an intermetallic compound, and a metal microcrystal mixture may be used. Further, as seen in stainless steel (hereinafter referred to as SUS), a passive oxide film may be formed on the surface. Further, there is no particular restriction on the purity of a single metal or alloy, and the present invention can be applied to any single metal or alloy that is used for ordinary general purposes.

Preferred metals are aluminum, iron, silicon, nickel, zinc, germanium, tin and copper and their alloys. A particularly preferred metal is aluminum. When aluminum is used, it is preferable to directly use an aluminum plate, which is a support for an original plate described later. Therefore, the surface hydrophilicity is enhanced by mechanical graining or electrolytic surface roughening, or anodic oxidation is performed. Or the like is used.

As a mode of use of the heat-responsive metal, a metal plate can be used as it is, or a suitable plastic film or other metal plate is used as a support and provided thereon by electroplating, bonding, or the like. Is also good. As the thickness of the metal plate on the support, any thickness smaller than the thickness of the support can be used.
About 01 mm to 0.4 mm, more preferably 0.02 mm to
0.2 mm.

In order to enhance the thermal responsiveness of the original printing plate, it is effective to provide a heat insulating layer below the image forming layer. When drawing by light-to-heat conversion is performed, a light-to-heat conversion layer may be provided as a lower layer when the functional surface is transparent to the light. This concludes the description of the thermoresponsive substance used in the present invention, particularly the thermoresponsive metal oxide and metal.

Next, the form of the printing plate used in the present invention will be described. Various forms and materials can be used for the printing plate according to the present invention. For example, a method in which a thin layer of a thermoresponsive material is directly provided by the above-described method such as vapor deposition, immersion or coating on a substrate surface of a plate cylinder of a printing press, a thermoresponsive material supported on a support, or a support. For example, a method in which a thin plate of a thermally responsive material having no such material is wound around a substrate of a plate cylinder to form a printing plate can be used. Of course, in addition to the above-described form of making a plate on a plate cylinder, a form in which the plate is made may be mounted on a rotary or flatbed printing press, as is generally performed.

When the heat-responsive substance is provided on a support, the support used is a plate which is not thermally decomposed even at a high hydrophilicity developing temperature and is dimensionally stable. A metal plate such as a SUS steel plate, a nickel plate, and a copper plate is preferable, and a flexible metal plate is particularly preferable. 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 waterproofed paper, polyethylene laminated paper, or impregnated paper, and it may be used as a printing plate.

Specifically, paper, paper laminated with a plastic sheet (eg, a sheet of polyethylene terephthalate, polyimide, etc.), a metal plate (eg, aluminum, zinc, copper, stainless steel, etc.), a plastic film (eg, Cellulose acetate, cellulose triacetate,
Cellulose propionate, cellulose butyrate, cellulose acetate butyrate, cellulose nitrate, polyethylene terephthalate, polyimide, polystyrene, polycarbonate, polyvinyl acetal, etc.), and paper or a plastic film on which a metal as described above is laminated or evaporated.

A preferred support is a polyester film, a polyimide film, aluminum, or a SUS plate which is hardly corroded on a printing plate. A polyimide film having high stability to the heating operation is particularly preferable.

A preferable polyimide film is a polyimide resin film obtained by polymerizing pyromellitic anhydride and m-phenylenediamine and then performing cyclic imidization.
This film is commercially available (eg, "Kapton" manufactured by Dupont Toray).

Preferred 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, titanium and the like. 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. However, completely pure aluminum is difficult to produce due to refining technology, and therefore may contain a slightly different element. 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 metal support used in the present invention is about 0.1 mm to 0.6 mm, preferably 0.15 mm to 0.4 mm, particularly preferably 0.2 mm
The thickness of other supports such as plastic and processed paper is about 0.1 mm to 2.0 mm, preferably 0.2 mm to 1.0 mm.

When an aluminum support is used, it is preferable to use a roughened surface. In this case, if desired, a degreasing treatment with a surfactant, an organic solvent, an alkaline aqueous solution, or the like is performed to remove the rolling oil on the surface prior to the surface roughening. The surface roughening treatment of the surface of the aluminum plate is performed by various methods, for example, a method of mechanically roughening the surface, a method of electrochemically dissolving the surface, and a method of selectively dissolving the surface chemically. It is performed by the method of causing. 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. In addition, as the electrochemical surface roughening method, a known method such as performing an alternating or direct current in a hydrochloric acid or nitric acid electrolyte can be used. Further, the roughened aluminum plate is subjected to an alkali etching treatment and a neutralization treatment as required, and then subjected to an anodic oxidation treatment, if necessary, in order to increase the water retention and abrasion resistance of the surface. The concentration of the anodic oxidation electrolyte is appropriately determined depending on the type of the electrolyte.

The conditions of the anodizing treatment vary depending on the electrolyte to be used, and thus cannot be specified unconditionally. / dm ² , voltage 1-100V, electrolysis time 10
A range of seconds to 5 minutes is appropriate. If the amount of the anodic oxide film is less than 1.0 g / m ² , the printing durability is insufficient,
The non-image portion of the lithographic printing plate is easily scratched, and so-called "scratch stain" in which ink adheres to the scratched portion during printing is likely to occur.

The configuration of the printing plate used in the printing method of the present invention has been described above. Next, specific embodiments of the offset printing method and the printing apparatus of the present invention will be described with reference to the drawings.

First, the thermal responsiveness of the surface of the thermally responsive material used in the present invention, such as a thermally responsive metal oxide and a thermally responsive metal, will be further described. FIG. 1 is a diagram showing an example of an experimental result for explaining the above-mentioned thermal responsiveness. The contact angle of water on the surface of titanium oxide when titanium oxide is heated at each temperature for 5 minutes is shown in FIG. The relationship between temperature and contact angle obtained by plotting measured values obtained using a contact angle measuring device CA-D manufactured by Interface Science Co., Ltd. against temperature is shown. Heating was performed from room temperature to 200 ° C. by using a small high-temperature chamber ST-110 (manufactured by Tabai Espec Corporation), and heating was performed by using an electric furnace KM-100 (manufactured by Toyo Seisakusho) at 200 ° C. or higher.

Needless to say, whether the surface is hydrophilic,
The measure of hydrophobicity can be represented by the magnitude of the contact angle with water. The larger the contact angle, the more hydrophobic the hydrophobicity, and the hydrophobicity can be rephrased as lipophilicity or ink-philicity. FIG. 1 shows that as the titanium oxide is heated, the surface contact angle increases, reaches a maximum when the temperature is 210 ° C., and decreases as the temperature is further increased.

That is, when the surface temperature of the titanium oxide is increased to reach the above-mentioned “hydrophobic temperature”, the titanium oxide becomes hydrophobic. . By heating the entire surface to a high-temperature hydrophilicity-expressing temperature, the surface becomes a clean and stable hydrophilic surface suitable for plate making, so that a printing plate with high reproducibility can be produced. The means for high-temperature heating is not particularly limited, but heating by electric heating is easy and control is also easy. Heat mode heating using radiation such as infrared rays or laser light is also a preferable heating means.

The range of the high-temperature hydrophilicity developing temperature differs depending on the type of the heat-responsive metal oxide and the metal and the heating rate.
The temperature is usually 200 ° C. or higher, and may be higher depending on the type of metal oxide and metal. The upper limit of the heating temperature for making the material hydrophilic may be high as long as no adverse chemical or structural change occurs in the metal oxide and metal, but as long as practical hydrophilicity is obtained, the temperature may be further increased. do not have to. When titanium oxide is used as the heat-responsive metal oxide, the temperature is preferably set to 700 ° C. or less in order to prevent a phase change of the titanium oxide. The temperature is preferably set to 400 ° C. or less in order to prevent thermal denaturation.

In the above description of the thermal responsiveness, the region of “hydrophobic expression temperature” specifically refers to a region where the contact angle on both sides of the maximum value of the contact angle is within 20 degrees. And corresponds to a practical hydrophobic region for receiving ink. In the experimental example of FIG. 1, the maximum value of the contact angle is 50 degrees, and the hydrophobicity development temperature range of 20 degrees on both sides is 155 to 240.
° C, but generally depends on the type of heat-responsive metal oxide or metal and other heat-responsive substances, the heating rate, and the heating atmosphere. For example, even at the same heating rate and the same heating atmosphere, the maximum value of the contact angle differs depending on the metal oxide such as titanium oxide, zinc oxide, and barium titanate, and the temperature range corresponding to the range of 20 degrees on both sides also differs. This temperature range changes when the heating rate is increased. Despite such slight differences, the hydrophobicity development temperature is generally in the range of 50 to 250 ° C, and most in the temperature range of 100 to 250 ° C. Therefore, by performing the heat mode drawing in this temperature region, it is possible to increase the difference between the hydrophobicity and the hydrophilicity of the image region and the non-image region, thereby increasing the discrimination between the image portion and the non-image portion. It is a feature of the present invention that the quality of the printed surface can be improved.

The heating means for forming the hydrophobic image area on the printing original plate may be a solid laser emitting infrared light, a semiconductor laser emitting infrared light or visible light, an infrared lamp, a xenon discharge lamp, a large capacity condenser. A direct image recording means such as a light-to-heat conversion drawing apparatus using a flash light generated by a discharge from the apparatus, a thermal recording head such as a thermal melting type or sublimation type thermal dye transfer, or the like is used. The heating temperature can be adjusted to an appropriate hydrophobicity developing temperature by controlling the light intensity of a light source used for heating or by controlling the power supplied to the thermal recording head and the drawing speed.

The writing of an image may be performed by either a surface exposure method or a scanning method. In the former case, an infrared irradiation method,
This is a method of irradiating a short time light of high illuminance of a xenon discharge lamp onto a master plate through a mask image to generate heat by light-heat conversion. When using a surface exposure light source such as an infrared lamp is preferred exposure amount varies by this illumination, usually, the surface exposure intensity before modulation by printing image of 0.1~10J / cm ² It is preferably in the range,
More preferably, it is in the range of ^{3 to 1} J / cm ² . When the support is transparent, exposure can be performed through the support and the mask image from the back side of the support. The exposure time is
0.01 to 1 msec, preferably 0.01 to 0.1 m
It is preferable to select the exposure illuminance so that the above-described exposure intensity can be obtained by the irradiation for sec. If the irradiation time is long,
It is necessary to increase the exposure intensity due to the competition between the heat energy generation rate and the generated heat energy diffusion rate.

In the latter case, a method is used in which a laser light source containing a large amount of infrared components is used to modulate a laser beam with an image and scan the original plate. Examples of the laser light source include a semiconductor laser, a helium neon laser, a helium cadmium laser, and a YAG laser. Irradiation can be performed with a laser having a laser output of 0.1 to 300 W. When a pulse laser is used, it is preferable to irradiate a laser having a peak output of 1000 W, preferably 2000 W. In this case, the exposure amount is preferably such that the surface exposure intensity before modulation with the printing image is in the range of 0.1 to 10 J / cm ² .
More preferably, it is in the range of ^{3 to 1} J / cm ² . When the support is transparent, exposure can be performed through the support from the back side of the support. When heating with light, for example, a light-to-heat conversion layer may be provided on a printing original plate, and the layer may absorb light energy to generate heat. Alternatively, the heat-responsive substance itself can be heated by absorbing light and generating heat by itself.

Further, when heating to the hydrophobic development temperature, a trace amount of impurities mixed in the heating atmosphere or organic compound vapor intentionally mixed are used to determine the maximum contact angle, the temperature of the maximum contact angle and the temperature and the hydrophobic development temperature. Affect the area. Of particular note is the phenomenon of increasing the contact angle. Therefore, by performing the heat mode recording in the presence of the vapor of the organic compound, the contact angle is increased, and the effect of discriminating hydrophilicity and hydrophobicity can be improved. Although the mechanism of this action is unknown, it is presumed that the organic compound is likely to be adsorbed on the heated original plate surface to form a hydrophobic film.

Preferred organic compounds having such excellent effects are those having a vapor pressure of at least 1 mmHg at a temperature of 400 ° C. and stable at a temperature at which the vapor pressure is 1 mmHg. If an organic compound having such a vapor pressure is present when performing drawing in the heat mode, the contact angle of the image area is increased and the discrimination between hydrophilicity and hydrophobicity is improved. More preferably,
The vapor pressure at a temperature of 300 ° C is at least 1 mmHg
And is an organic compound that is stable at a temperature at which the vapor pressure becomes 1 mmHg. More preferably, the boiling point is 30-4.
It is an organic compound which is stable at a temperature of 00 ° C and in a temperature range of 30 to 400 ° C.
350 ° C. Organic compounds having a boiling point in this temperature range include aliphatic and aromatic hydrocarbons, aliphatic and aromatic carboxylic acids, aliphatic and aromatic alcohols, aliphatic and aromatic esters, aliphatic and aromatic It is found in ethers, organic amines, organic silicon compounds, and various solvents and plasticizers that are known to be able to be added to printing inks.

Preferred aliphatic hydrocarbons are those having 8 to 3 carbon atoms.
0, more preferably an aliphatic hydrocarbon having 8 to 20 carbon atoms, and a preferred aromatic hydrocarbon has 6 to 40 carbon atoms.
And more preferably an aromatic hydrocarbon having 6 to 20 carbon atoms. Preferred aliphatic alcohols have 2 to 30 carbon atoms.
Are more preferably aliphatic alcohols having 2 to 18 carbon atoms, and preferred aromatic alcohols are those having 6 to 30 carbon atoms.
And more preferably an aromatic alcohol having 6 to 18 carbon atoms. Preferred aliphatic carboxylic acids have 2 to 24 carbon atoms.
Aliphatic carboxylic acid, more preferably having 2 to 2 carbon atoms
Preferred are aliphatic monocarboxylic acids having 20 and aliphatic polycarboxylic acids having 4 to 12 carbon atoms, and preferred aromatic carboxylic acids are those having 6 to 30 carbon atoms, and more preferably having 6 to 30 carbon atoms.
18 aromatic carboxylic acids. Preferred aliphatic esters have 2 to 30 carbon atoms, more preferably 2 to 1 carbon atoms.
And preferred aromatic esters are those having 8 to 30 carbon atoms, more preferably 8 to 18 carbon atoms.
Is an aromatic carboxylate. Preferred aliphatic ethers are those having 8 to 36 carbon atoms, more preferably 8 carbon atoms.
To 18 aromatic ethers, and preferred aromatic ethers are those having 7 to 30 carbon atoms, more preferably 7 to 1 carbon atoms.
8 aromatic ethers. In addition, carbon number 7-30
And more preferably an aliphatic or aromatic amide having 7 to 18 carbon atoms.

Specific examples include aliphatic aliphatics such as 2,2,4-trimethylpentane (isooctane), nonane, decane, n-hexadecane, octadecane, eicosane, methylheptane, 2,2-dimethylhexane and 2-methyloctane. Hydrocarbons: benzene, toluene, xylene,
Aromatic hydrocarbons such as cumene, naphthalene, anthracene and styrene; dodecyl alcohol, octyl alcohol, n-octadecyl alcohol, 2-octanol,
Monohydric alcohols such as lauryl alcohol; polyhydric alcohols such as propylene glycol, triethylene glycol, tetraethylene glycol, glycerin, hexylene glycol, dipropylene glycol; benzyl alcohol, 4-hydroxytoluene, phenethyl alcohol, 1-naphthol, -Naphthol, catechol,
Aromatic alcohols such as phenol; acetic acid, propionic acid, butyric acid, caproic acid, acrylic acid, crotonic acid, capric acid, stearic acid, oleic acid and other aliphatic monocarboxylic acids; oxalic acid, succinic acid, adipic acid, maleic acid Polyvalent aliphatic carboxylic acids such as acid and glutaric acid; aromatic carboxylic acids such as benzoic acid, 2-methylbenzoic acid and 4-methylbenzoic acid; ethyl acetate, isobutyl acetate, acetic acid-
Aliphatic esters such as n-butyl, methyl propionate, ethyl propionate, methyl butyrate, methyl acrylate, dimethyl oxalate, dimethyl succinate and methyl crotonate; aromatics such as methyl benzoate and methyl 2-methylbenzoate Carboxylic acid esters; organic amines such as imidazole, triethanolamine, diethanolamine, cyclohexylamine, hexamethylenetetramine, triethylenetetramine, aniline, octylamine, aniline, phenethylamine; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, benzophenone, and methoxy Ethers such as benzene, ethoxybenzene, methoxytoluene, lauryl methyl ether, stearyl methyl ether, stearyl amide,
Amides such as benzoylamide and acetamide are exemplified.

Also, oils and fats such as linseed oil, soybean oil, poppy oil, safflower oil, etc., which are components of the printing ink, tributyl phosphate, tricresyl phosphate, dibutyl phthalate,
Plasticizers such as butyl laurate, dioctyl phthalate, and paraffin wax are also included.

In addition, organic solvents such as ethylene glycol monoethyl ether, cyclohexanone, methyl cellosolve, butyl cellosolve, cellosolve acetate, 1,4-dioxane, dimethylformamide and acrylonitrile having a boiling point within the above preferred range can also be used.

Preferred organosilicon compounds are organopolysiloxane compounds typified by dimethyl silicone oil, methylphenylsilicone oil and the like, especially organopolysiloxanes having a degree of polymerization of 12 or less. These preferred organopolysiloxanes have one to two organic groups attached per siloxane bond unit,
The organic group includes an alkyl group and an alkoxy group having 1 to 18 carbon atoms, an alkenyl group and an alkynyl group having 2 to 18 carbon atoms, an aryl group having 6 to 18 carbon atoms, and a 7-1 to 1 carbon atom.
And an alicyclic group having 5 to 20 carbon atoms. Further, these organic substituents may be further substituted with a halogen atom, a carboxyl group, or a hydroxy group.
Further, the aryl group, the aralkyl group and the alicyclic group may be further substituted with a lower alkyl group such as a methyl group, an ethyl group or a propyl group within the above-mentioned carbon number range.

Specific examples of preferred organosilicon compounds that can be used in the present invention are the following compounds, but the present invention is not limited thereto.

Preferred polyorganosiloxanes include a dialkylsiloxane group having an alkyl group having 1 to 5 carbon atoms and a dialkoxysiloxane having an alkoxy group having 1 to 5 carbon atoms as a repeating unit and having a terminal having 1 carbon atom.
To 5 alkyl groups, amino groups, hydroxy groups, 1 carbon atoms
Polysiloxane having a polymerization degree of 2 to 12 which is a hydroxyalkyl group having 1 to 5 carbon atoms or an alkoxy group having 1 to 5 carbon atoms, and a polymerization unit having a terminal having a hydroxy group, a methoxy group or an ethoxy group having a terminal of a hydroxy group, a methoxy group or an ethoxy group having methoxyethoxysiloxane as a repeating unit.
2 polysiloxane. Specifically, dimethylsiloxane having a polymerization degree of 2 to 10, dimethylsiloxane-methylphenylsiloxane copolymer having a polymerization degree of 2 to 10, dimethylsiloxane-diphenylsiloxane copolymer having a polymerization degree of 2 to 8, Are 2 to 8 dimethylsiloxane-monomethylsiloxane copolymers, and the terminals of these silicone oils are trimethylsilane groups. others,
1,3-bis (3-aminopropyl) tetramethyldisiloxane, 1,5-bis (3-aminopropyl) hexamethyltrisiloxane, 1,3-dibutyl-1,1,1
3,3-tetramethyldisiloxane, 1,5-dibutyl-1,1,3,3,5,5-hexaethyltrisiloxane, 1,1,3,3,5,5-hexaethyl-1,5-
Examples include dichlorotrisiloxane, 3- (3,3,3-trifluoropropyl) -1,1,3,3,5,5,5-heptamethyl-trisiloxane, decamethyltetrasiloxane, and the like.

Particularly preferred compounds include so-called silicone oils, such as dimethyl silicone oil (commercially available, for example, silicone KF96 (manufactured by Shin-Etsu Chemical Co., Ltd.)) and methylphenyl silicone oil (commercially available, for example, silicone KF50 (Shin-Etsu Chemical) Industrial Co., Ltd.
Methyl Hydrogen Silicone Oil (a commercially available product such as Silicone KF99 (Shin-Etsu Chemical Co., Ltd.)
Manufactured).

In addition, silane compounds such as n-decyltrimethoxysilane, n-decyltri-t-butoxysilane, n-octadecyltrimethoxysilane, n-octadecyltriethoxysilane and dimethoxydiethoxysilane can also be mentioned. .

In order to carry out heating to a temperature at which hydrophobicity is exhibited in an atmosphere of an organic compound, an organic compound-filled container is placed in a jacket of a heating section covering the surface of the original plate, and the vapor of the organic compound is jacketed during the heating time. It is good to exist in. Alternatively, paper or cloth impregnated with an organic compound may be inserted into the jacket and heated.

The heat response characteristics and the heat response material of the printing plate according to the present invention have been described above. Next, a printing method and an apparatus for mounting the original plate will be described.

The printing original plate can be sent to the offset printing step without development after the lipophilic image is provided on the surface of the thermoresponsive substance. Therefore, it has many advantages, mainly simplicity, as compared with the known lithographic printing method. That is, as described above, the chemical treatment with the alkaline developer is unnecessary, and the accompanying wiping and brushing operations are not required, and further, there is no environmental load due to the discharge of the waste developer. Another advantage is that the selection range of the image forming means is wide, and printing is easily performed from the simple image recording means as described above.

The non-image area of the lithographic printing plate obtained from the heat-responsive substance is sufficiently hydrophilic. However, if desired, washing water, a rinsing liquid containing a surfactant, a gum arabic or a starch derivative may be used. It may be post-treated with a desensitizing solution containing the same. As the post-processing when the image recording material of the present invention is used as a printing plate material, these processings can be used in various combinations. As a method, a sponge or absorbent cotton impregnated with the surface conditioning liquid is applied on a lithographic printing plate, or a method in which the printing plate is immersed in a vat filled with the surface conditioning solution and applied, Application by an automatic coater or the like is applied. Further, making the application amount uniform with a squeegee roller after the application may give more preferable results. The application amount of the surface conditioning liquid is generally 0.03 to 0.8 g / m ^2.
(Dry weight) is appropriate. The lithographic printing plate obtained by such a process is set on an offset printing press or the like, or is made on a printing press, and used for printing a large number of sheets.

Next, the process of reproducing the printing plate after printing will be described. After printing, the printing plate is washed away with a hydrophobic petroleum-based solvent to remove attached ink. Examples of the solvent include aromatic hydrocarbons such as kerosene and isoper as a commercially available printing ink solution, and benzol, toluene, xylol, acetone, methyl ethyl ketone, and a mixed solvent thereof may be used. If the image substance does not dissolve, gently wipe it with a cloth.
In some cases, a 1/1 mixed solvent of toluene / Daiclean may be used.

The printing plate from which the ink has been washed away is heated to a high-temperature hydrophilicity developing temperature to restore the hydrophilicity uniformly over the entire plate surface. The heating temperature is 200 ° C. or higher and the temperature is higher than the upper limit of the hydrophobicity developing temperature. 5 minutes, 2 at 100 ° C
A heat treatment time on the order of minutes is preferred. There is no problem even if the heat treatment time is extended, but after the hydrophilicity of the surface is restored, even if the time is extended, no further advantage is produced.

As the heat source used for regeneration, any means can be used as long as it satisfies the above-mentioned conditions of temperature and time.
Examples of heating means include radiant heating by direct infrared irradiation, indirect infrared irradiation with a heat absorbing sheet such as black carbon paper contacting the printing plate surface, insertion into a temperature-controlled air bath, hot plate and other heat sources. Contact heating with the plate,
Examples include contact with a heating roller. The printing plate regenerated from the used printing plate in this way is stored so as to avoid exposure to actinic light and is ready for the next printing.

Although the number of repetitive reproductions of the printing plate according to the present invention has not been completely grasped, it is at least 15 times or more. It is considered that it is restricted by mechanical deformation (strain) of the plate material.

The operation of heating the printing plate in the present invention has been described. Next, a method and an apparatus for performing printing by mounting the original plate will be described with reference to the drawings. The printing plate having the heat-responsive substance on the surface may be fixed as a component of the plate cylinder, or may be detachable. Hereinafter, in the description after FIG. 2, the former in which the simplicity of the present invention is remarkably exhibited, that is, an example in which the plate cylinder is a printing original plate will be described.

FIG. 2 is a diagram showing the configuration of the offset printing apparatus according to the first embodiment of the present invention. As shown in FIG. 2, the offset printing apparatus according to the first embodiment of the present invention includes a plate cylinder 1 having the above-described thermoresponsive material such as titanium oxide or zinc oxide on its surface, and a high-temperature hydrophilic property for the plate cylinder 1. A high-temperature heating unit 2 that is heated at the developing temperature to make the entire surface hydrophilic, a cooling unit 19 that is provided as needed to cool the high-temperature heated plate cylinder to a temperature lower than the hydrophobic developing temperature, and that the entire surface is made hydrophilic by heating. A thermal recording section 5 for performing drawing in a heat mode on the plate cylinder 1 at a hydrophobic development temperature, and an ink / fountain solution for supplying ink and dampening solution to the plate cylinder 1 on which the drawing in the heat mode is performed. A supply unit 3, an ink washing unit 4 for removing ink remaining on the plate cylinder 1 after printing, a blanket 6 as an intermediate for transferring the ink held on the plate cylinder 1 to paper, and a blanket 6 Holds fed paper A impression cylinder 7 that, these members are made of housed within the body 8.

Next, the thermosensitive recording section 5 will be described.
In order to form an oleophilic image area on the plate cylinder 1 whose entire surface is uniformly hydrophilized, the surface of the plate cylinder 1 is heated imagewise to a hydrophobic development temperature by the heat-sensitive recording unit 5.
As a means for heating like this image, as described above,
Methods such as infrared light, laser light, and contact heating can be selected.

FIG. 3 is an element configuration diagram of a thermal recording section using a thermal recording head which is a typical example of the thermal recording section.
The thermal recording unit 5 of the contact heating type shown in FIG. 3 is signalized from a thermal head 18 that performs drawing in a heat mode in close contact with the surface of the plate cylinder 1 and an image to be printed in the editing / layout W / S20. Image signal S input to the recording unit
And a thermal head driving unit 19 for driving the thermal head 18 to draw on the surface of the plate cylinder 1 in the heat mode. The thermal head 18 has a plurality of fine heating elements extending in an array or matrix in the direction of the rotation axis of the plate cylinder 1.
The drawing is performed in the heat mode. And
When the plate cylinder 1 rotates, drawing in the heat mode is performed on the surface of the plate cylinder 1, a portion of the plate cylinder 1 where drawing is not performed is a hydrophilic non-image area, and a drawn portion is lipophilic. This is an image area.

FIG. 4 shows another example of the structure of the thermal recording section 5. A thermal recording unit 5 in another configuration example shown in FIG.
The laser light source 21 is driven to modulate the laser light based on the image signal S which is converted from the image to be printed in the editing / layout W / S 20 and input to the recording unit, so that the laser light is modulated on the surface of the plate cylinder 1. And a laser light source driving unit 22 for performing drawing in the heat mode. The light source 21 is configured to move the emitted laser light relative to the plate cylinder 1 in the direction of the rotation axis of the plate cylinder 1 to scan over the plate cylinder 1. The surface of the plate cylinder 1 is exposed to the modulated laser light, the portion of the plate cylinder 1 not irradiated with the laser light is made a hydrophilic non-image area, and the part irradiated with the laser light is the lipophilic image. The area is used for drawing in the heat mode. The laser is preferably an infrared laser, but may not necessarily be an infrared laser as long as the light-to-heat conversion mechanism is incorporated in the printing plate.

When image recording in the heat mode is performed in the presence of an organic compound, an organic compound vapor supply means for introducing an organic compound vapor into the heat-sensitive recording section shown in FIGS. 3 and 4, for example, an organic solvent A container for evaporation filled with the above, and further provided with a diffuser, or provided with a simple heating means.

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

Further, in the present invention, the heat-sensitive recording section 5 includes not only a heat-sensitive recording head and a laser beam but also a light-heat conversion heating device for irradiating a heat ray such as light from an infrared lamp through an image mask impermeable to heat rays. A light-to-heat conversion heating method in which a high-illuminance instant flash using a large-capacity condenser is performed through an image mask can also be adopted.

Next, the operation of the first embodiment will be described. First, the portion of the plate cylinder 1 that passes while rotating the high-temperature heating unit 2 is heated over the entire surface of the plate cylinder 1 that has passed through the heating unit of the plate cylinder 1 due to heat radiation from the heating resistor of the high-temperature heating unit 2. The surface of No. 1 changes from lipophilic to hydrophilic.
When the high-temperature heating is completed, the plate cylinder that has been made hydrophilic is
It is cooled to a temperature not higher than the hydrophobicity development temperature. In addition to the natural cooling method by heat radiation, the cooling is performed by heating the high-temperature heating unit 2 or passing cooling water to the cooling jacket of the cooling unit 9 at the same time or after the heating, A forced cooling system is also used in which a cooling section 9 cools a portion of the rotating plate cylinder that has passed through the high-temperature heating section 2 and has been rendered hydrophilic. In the heat-sensitive recording unit 5, drawing in a heat mode is performed by heating to a temperature at which hydrophobicity is exhibited. The area where imagewise heating is performed is an image area having lipophilicity, and the area where heating is not performed is a non-image area having hydrophilicity. When the drawing in the heat mode is completed, the ink and dampening solution are supplied to the plate cylinder 1 from the ink / fountain solution supply unit 3. Thereby, plate cylinder 1
The lipophilic image area holds ink, and the hydrophilic non-image area holds fountain solution without holding ink.

Thereafter, a sheet is supplied between the blanket 6 and the impression cylinder 7 as shown by an arrow A, and the ink held in the plate cylinder 1 is transferred to the sheet via the blanket 5 to perform offset printing. Is

After printing is completed, the ink cylinder 4 is used by the ink washing unit 4.
The remaining ink is removed. Then, by heating the plate cylinder 1 through the high-temperature heating unit 2, the image-like lipophilic area of the plate cylinder 1 is erased, and the state before drawing in the heat mode is returned.

As described above, according to the offset printing apparatus of the present invention, a printing screen can be formed on the plate cylinder 1 only by high-temperature heating and drawing in the heat mode over the entire surface. Offset printing in which the sharpness of the image is maintained. In addition, since the original state can be returned by washing the plate cylinder 1 and heating it again at a high temperature, the plate cylinder 1 can be used repeatedly, whereby the printed matter can be provided at low cost. . Further, since there is no need to remove the plate cylinder 1 from the printing apparatus, dust and the like do not adhere to the printing apparatus as in the case of a conventional PS plate, thereby improving print quality.

Further, the plate cylinder 1 was used as a printing original plate,
By arranging the high-temperature heating unit 2, the ink / fountain solution supply unit 3, the ink washing unit 4, and the thermal recording unit 5 around the plate cylinder 1, simply rotating the plate cylinder 1 makes the entire surface of the original plate hydrophilic. Since it is possible to perform printing in the heat mode, supply ink and dampening water, and further perform ink washing after printing, the apparatus can be made compact and space can be saved. it can. Example 1 performed below in accordance with the above aspect of the present invention
Is described.

[Example 1] An example according to the first embodiment will be described. Copper is added to 99.5% by weight aluminum.
Weight%, titanium 0.03 weight%, iron 0.3 weight%,
A 0.30 mm-thick rolled sheet of JIS A1050 aluminum material containing 0.1% by weight of silicon was mixed with a 20% by weight aqueous suspension of pumicestone (manufactured by Kyoritsu Ceramics) of 400 mesh,
The surface was grained using a rotating nylon brush (6,10-nylon), and then thoroughly washed with water. This was treated with a 15% by weight aqueous sodium hydroxide solution (aluminum 4.
5% by weight) and the amount of aluminum dissolved is 5 g /
After etching to m ² , it was washed with running water. Further, it is neutralized with 1% by weight nitric acid, and then, in a 0.7% by weight aqueous nitric acid solution (containing 0.5% by weight of aluminum), a rectangular wave having a voltage of 10.5 volts at the time of anode and a voltage of 9.3 volts at the time of cathode. Alternating waveform voltage (current ratio r = 0.90, Japanese Patent Publication No. 58-5796)
Using the current waveform described in the embodiment of
Electrolytic surface-roughening treatment was carried out at an anode charge of 0 clones / dm ² . After washing with water, it 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, at 50 ° C, 3
After immersing in 0% by weight sulfuric acid aqueous solution and desmutting,
Washed with water.

Further, a 20% by weight aqueous solution of sulfuric acid at 35 ° C.
DC current in (aluminum 0.8% by weight)
Then, a porous anodic oxide film forming treatment was performed. That is, current density
Degree 13A / dm^TwoPerform electrolysis with the anode and adjust the electrolysis time
Oxide film weight 2.7g / m^TwoAnd After washing this support with water,
30 seconds in a 3% by weight aqueous solution of sodium silicate at 70 ° C
It was immersed, washed and dried. Obtained as above
Aluminum support is Macbeth RD920 reflection densitometer
Is 0.30, and the center line average roughness is
It was 0.58 μm. Then this aluminum support
Into a vacuum evaporation apparatus, and a total pressure of 1.5 × 10 ^-FourTorr
Titanium metal under the condition of oxygen gas with a partial pressure of 70%
The piece is heated electrically to deposit it on an aluminum
A titanium oxide thin film was formed. X-ray solution
Amorphous / anatase / rutile crystal structure ratio by precipitation method
Is 1.5 / 6.5 / 2 and TiO_TwoThe thickness of the thin film is 900
Angstrom. This is wound around the substrate of plate cylinder 1
This was used as an original plate for on-press printing.

The heating resistor of the high-temperature heating section 2 was energized to slowly rotate the plate cylinder 1 around which the original plate was wound. The temperature of the original sheet passing through the heating section is 300 ° C or higher (up to 380 °
The passing time in the heating zone as C) was 2 minutes. The energization was stopped and the plate cylinder was allowed to cool to room temperature. , And each part was between 7 and 9 degrees.

Next, a 150 μm × 15 layer having a sialon wear-resistant protective layer provided on the Ta—SiO ₂ heating resistor of the thermal recording section 5 was prepared.
Using a heating element array in which thermal heads of 0 μm are arranged at intervals of 250 μm, the prints were heated by bringing them into contact with the titanium oxide surface layer. The used thermal head is 5msec
It reaches 210 ° C. by energization and reaches 450 ° C. by energization for 10 msec. Temperature was separately confirmed by temperature measurement. Recording speed is 2.5m / s
ec. At this time, the contact angle was determined from the experimental example shown in FIG. 1 by CONTACT-ANGLE METER manufactured by Kyowa Interface Science Co., Ltd.
The contact angle with water measured by the air drop method using CA-D can be regarded as 50 degrees.

The plate cylinder 1 is used for a single-sided printing machine of Oliver 52 manufactured by Sakurai Co., and the dampening water is supplied to the ink / fountain solution supply unit 3 by using pure water, and the ink is supplied by Newc manufactured by Dainippon Ink and Chemicals, Inc.
Offset printing was performed on 1,000 sheets using hampion F gloss 85 ink. A clear printed matter was obtained from the start to the end, and no damage to the plate cylinder 1 was observed.

Next, in the washing section 4, the surface of the plate cylinder 1 is thoroughly washed by impregnating a 1/1 mixed solution of printing ink washing liquid Daiclean R (released by Dainippon Ink and Chemicals) and toluene into a waste cloth. To remove the ink. After energizing the high-temperature heating unit 2 again and heating it under the same conditions as before, the contact angle was measured by the same method as before while cooling to room temperature.
Every part of the plate surface was between 7 and 9 degrees.

Next, on the surface of the plate cylinder 1, a different drawing was performed by a thermal head under the same conditions as described above. The plate cylinder 1 is used for a single-sided printing press of Oliver 52 manufactured by Sakurai Co., Ltd., and the dampening solution is supplied to the ink / fountain solution supply unit 3 by pure water and the ink is supplied by Dainippon Ink and Chemicals, Newchampion.
Offset printing was performed on 1000 sheets using F gloss 85 ink. A clear printed matter was obtained from the start to the end, and no damage to the plate cylinder 1 was observed.

When the above repetition was performed 5 times, no change was observed in the contact angle value after heating at a high temperature, the contact angle recovery speed due to heating, and the sharpness of the image on the printed surface. From these results, it is possible to print by high-temperature heating and heat mode printing using a printing plate of form 1 using a printing original plate provided with a titanium oxide layer on an aluminum support, and printing only by washing and removing the ink. It was shown that the original could be reused repeatedly.

Example 2 A SUS plate having a thickness of 100 μm was set in a vacuum vapor deposition apparatus, and zinc selenide was vapor-deposited to a thickness of 1000 Å under a vacuum of a total pressure of 5 × 10 ⁻³ Torr. This was oxidized in air at 600 ° C. for 2 hours to form a zinc oxide thin film on one surface of the SUS plate.

100 micron SU with zinc oxide coating
The S plate was wound around the substrate of the plate cylinder 1 of the printing apparatus of the first embodiment in the same manner as in the first embodiment to obtain an on-press plate making type original plate.

Electric current was supplied to the heating resistor of the high-temperature heating section 2 to slowly rotate the plate cylinder 1 around which the original plate was wound. The temperature of the original sheet passing through the heating section is 300 ° C or higher (up to 380 °
The passing time in the heating zone as C) was 2 minutes. The energization was stopped and the plate cylinder was allowed to cool to room temperature. , Both parts were between 15 and 18 degrees.

Next, a 150 μm × 15 sialon wear-resistant protective layer was provided on the Ta—SiO ₂ heating resistor of the thermal recording section 5.
Using a heating element array in which thermal heads of 0 μm are arranged at intervals of 250 μm, the prints were heated by bringing them into contact with the titanium oxide surface layer. Set the scanning speed of the used thermal head to
It was confirmed by separately performing temperature measurement that the surface of zinc oxide was kept at 210 ° C. by energization at 2.5 m / sec. The recording speed was 2.5 m / sec.

The plate cylinder 1 is used in a single-sided printing machine of Oliver 52 manufactured by Sakurai Co., Ltd., and the dampening water is supplied to the ink / fountain solution supply unit 3 by pure water, and the ink is supplied by Newc manufactured by Dainippon Ink and Chemicals, Inc.
Offset printing was performed on 1,000 sheets using hampion F gloss 85 ink. A clear printed matter was obtained from the start to the end, and no damage to the plate cylinder 1 was observed.

Next, in the washing section 4, the surface of the plate cylinder 1 is thoroughly washed by soaking a 1/1 mixture of a printing ink washing liquid Daiclean R (released by Dainippon Ink and Chemicals) and toluene into a waste cloth. To remove the ink. After energizing the high-temperature heating unit 5 again to heat it under the same conditions as before, the contact angle was measured by the same method as before while cooling to room temperature.
Every part of the plate surface was between 15 and 18 degrees.

Next, a different image was drawn on the surface of the plate cylinder 1 with a thermal head under the same conditions as described above. The plate cylinder 1 is used for a single-sided printing press of Oliver 52 manufactured by Sakurai Co., Ltd., and the dampening solution is supplied to the ink / fountain solution supply unit 3 by pure water and the ink is supplied by Dainippon Ink and Chemicals, Newchampion.
Offset printing was performed on 1000 sheets using F gloss 85 ink. A clear printed matter was obtained from the start to the end, and no damage to the plate cylinder 1 was observed.

From these results, it is possible to perform printing by high-temperature heating and heat mode printing using the printing plate of Embodiment 1 using a printing original plate provided with a zinc oxide layer on a SUS support, and furthermore, washing and removing the ink. It was shown that only the original printing plate could be reused repeatedly.

[Example 3] An aluminum support anodized in the same manner as in Example 1 was replaced with CsLa ₂ NbTi _2.
The surface was hydrolyzed by immersion in a 20% ethanol solution containing cesium ethoxide, titanium butoxide, lanthanum isobutoxide, and niobium ethoxide corresponding to the stoichiometric ratio of O ₁₀ , and the surface was hydrolyzed. A thin film of CsLa ₂ NbTi ₂ O _{10 having} a thickness of 1000 Å was formed on the body surface.

The same plate making, printing, washing with ink, and reprinting were performed in the same manner as in Example 1 except that the aluminum support with the composite metal oxide thin film was wound around the base of the plate cylinder to form an original plate. The contact angle of water to the hydrophilic region by the high-temperature heating is 15 to 22 degrees for the first and second times, and the quality of the printed surface is free from background smear for both the first and second times. The discrimination of the regions was also sufficient.

Example 4 Same as that used in Example 1.
Aluminum support with roughening and anodizing
Using barium titanate as a thermo-responsive metal oxide
An original plate was produced. That is, the above aluminum support
The body was set in a sputtering apparatus and 5.0 × 10^-7
Evacuate to Torr. Heating the support to 200 ° C.,
Ar / O_TwoGas pressure so as to be 90/10 (molar ratio)
To 5x10^-3Set to Torr, SiO _TwoR target
F power 200W is input and SiO_Two1μm thin layer of
Formed. Subsequently, the Ar gas pressure was set to 5 × 10^-3Set to Torr
Then, apply RF power 200W to the Si target
A 1 μm thin film of Si was formed. Then the gas pressure of Ar
5x10^-3Torr, 6 inch φ barium titanate
RF power 200W is applied to the sintering target
A barium titanate thin film having a thickness of 1000 ° was formed. X-ray
According to the analysis method, this thin film was polycrystalline.

The barium titanate thin film and the aluminum support on which the light-to-heat converting Si thin film and the heat insulating layer of SiO ₂ were mounted were wound around the base of the plate cylinder and used as a master plate. The same plate making, printing, ink washing and removal, and reprinting were performed as in Example 1 except that an infrared laser light recording device was used instead. In the infrared laser light recording apparatus, drawing was performed by scanning exposure with a beam width of 45 μm of a solid infrared laser light having an output of 500 mW. In this case, the irradiated infrared light is
Since the layer absorbs heat and generates heat, the barium titanate layer can be heated. The temperature of the barium titanate layer in the light-irradiated portion when performing infrared laser drawing under the above conditions was determined by comparison with a test measured by contact with the thermal head.
It has been found to be 50 ° C. The contact angle of water to the hydrophilic region by high-temperature heating was 1 for both the first and second times.
4 to 20 degrees, and the quality of the printed surface
There were no background stains at each time, and the discrimination between the image area and the non-image area was sufficient.

Example 5 A polyimide (pyromellitic anhydride / m-phenylenediamine copolymer) film (trade name: Kapton, manufactured by Dupont Toray Co., Ltd.) having a thickness of 100 μm was used in the same manner as in Example 4. A sample was prepared in which a light-to-heat conversion layer was provided and a titanium dioxide thin film was provided thereon. That is, the aluminum support is set in a sputtering apparatus, and evacuated to 5.0 × 10 ⁻⁷ Torr.
The support was heated to 200 ° C. and the Ar / O ₂ was 90/10
The gas pressure so that the molar ratio was set to 5 × 10 ^-3 Torr, to form a thin layer of SiO ₂ of 1μm by supplying an RF power 200W to SiO ₂ target. Subsequently, the gas pressure of Ar was set to 5 × 10 ⁻³ Torr, and RF power of 200 W was applied to a Si target to form a 1 μm thin film of Si. Further, to set the gas pressure so as Ar / O ₂ is 60/40 (molar ratio) to 5 × 10 ^-3 Torr, the gas pressure was set to 5 × 10 ^-3 Torr, R a titanium metal target
An F power of 200 W was applied to form a titanium dioxide thin film by vapor deposition. The crystal component of this thin film was determined to have an amorphous / anatase / rutile crystal structure ratio of 1.5 / 6.5 by X-ray analysis.
/ 2, and the thickness of the titanium dioxide thin film was 900 Å. The polyimide support on which the titanium dioxide thin film, the light-heat converting Si thin film and the heat insulating layer of SiO ₂ were mounted was wound around the substrate of the plate cylinder and used as an original plate, and an infrared laser was used instead of the thermal recording head in the thermal recording section. Except that an optical recording apparatus was used, the same plate making, printing, ink washing and removal, and reprinting were performed as in Example 1. In the infrared laser light recording apparatus, drawing was performed by scanning exposure with a beam width of 45 μm of a solid infrared laser light having an output of 500 mW. The contact angle of water to the hydrophilic region by the high-temperature heating is 11 to 17 degrees in the first and second times, and the quality of the printed surface is free from background smear in the first and second times. The discrimination of the regions was also sufficient.

[Example 6] A glass tube having an inner diameter of about 30 mm (a diversion filter was diverted) was placed sideways at the air intake of the thermal recording unit, and the air in the room passed through the glass tube and passed through the thermal recording unit. The structure is taken into the inside of the. Silicone oil [Product name: Silicone KF99 (Shin-Etsu Chemical Co., Ltd.)
) Was poured into the lower half of the glass tube so that the volume ratio became 50%. The temperature of the air intake rises from room temperature to 150 ° C. while passing through the tube. Silicone KF99 has at least 1 mmH
Since the air has a vapor pressure of not less than g, the air introduced into the heat-sensitive recording section contains the vapor of silicone KF99. The air exchange rate in the tube heat recording unit having the internal volume of the space of 2 liters was 10 vol% per minute. Except that the vapor of the organopolysiloxane compound is introduced, plate making and printing are performed under the same conditions using the same original plate and the same apparatus as in Example 1, and the used printing plate is reproduced by the same method and re-used. Printing was done. The maximum contact angle with water of the image area recorded in the heat mode appears at 190 ° C., and the value of the contact angle with water (CONTACT-AN manufactured by Kyowa Interface Science Co., Ltd.)
GLE METER CA-D as measured by the air drop method) was 73 degrees. When this result is compared with the result obtained in Example 1, the temperature at which the contact angle is maximized changes by performing the heating at the hydrophobic development temperature in the presence of the organosilicon compound vapor. It can be seen that the lipophilicity-hydrophilicity discrimination property was remarkably increased.

Next, using this printing plate, 1000
Offset printing of one sheet was performed. A clear printed matter was obtained from the start to the end as in Example 1. However, when printing was continued and 5000 sheets were printed, in Example 1 in which the silicone KF99 was used and printing was performed, it was visually recognized. However, in Example 6 in which printing was performed in the presence of silicone KF99, no ink stain was found and no damage to the plate cylinder 1 was found.

Next, a second embodiment of the present invention will be described. [Embodiment 2] FIG. 5 is a view showing the configuration of an offset printing apparatus according to a second embodiment of the present invention. The offset printing apparatus shown in FIG. 5 is similar to the offset printing apparatus shown in FIG.
It is configured by being arranged in series in the main body 12,
Color printing is performed using inks of Y (yellow), M (magenta), C (cyan), and B (black), respectively.

Each of the printing units 11Y, 11M, 11C,
Since the configuration and operation of 11B are the same as those of the offset printing apparatus shown in FIG. 2, detailed description will be omitted. In the second embodiment, each of the printing units 11Y, 11M,
The difference is that the colors of the inks supplied in the ink / fountain solution supply units 11C and 11B are Y (yellow), M (magenta), C (cyan), and B (black), respectively.

Next, the operation of the second embodiment will be described. First, the printing units 11Y, 11M, 11C,
In 11B, the entire surface of the plate cylinder 1 is made hydrophilic by passing the entire surface of the plate cylinder 1 through the high-temperature heating unit at 350 ° C. for 2 minutes by applying a current to the heating resistor of the high-temperature heating unit while slowly rotating the plate cylinder 1 in 11B. After that, an image representing each color is drawn in the heat mode by the thermal recording using the thermal head described in the first embodiment. And each printing unit 11
Y, M, C, and B inks are supplied from ink / fountain solution supply units of Y, 11M, 11C, and 11B, and the plate cylinders 1 of the printing units 11Y, 11M, 11C, and 11B are supplied.
Hold the ink and fountain solution. Thereafter, paper is supplied as shown by arrow B in FIG.
The Y, 11M, 11C, and 11B inks are transferred to paper. That is, in the printing unit 11Y, the Y ink is transferred, in the printing unit 11M, the M ink is transferred, in the printing unit 11C, the C ink is transferred, and in the printing unit 11B, the B ink is transferred. . As a result, a color image is printed on the sheet.

After the printing, the printing units 11Y and 11Y
The ink remaining on the plate cylinder is removed by the ink cleaning units M, 11C and 11B. Thereafter, the entire surface of the plate cylinder 1 is heated at 350 ° C. for 15 seconds by energizing the heating resistor of the high-temperature heating unit while slowly rotating the plate cylinder 1, so that the plate cylinder 1 is brought into a state before drawing in the heat mode. Return.

[Embodiment 3] Next, a third embodiment of the present invention will be described. FIG. 6 is a diagram showing a configuration of an offset printing apparatus according to a third embodiment of the present invention, and FIG. 7 is an enlarged view of a main part of FIG. The offset printing apparatus shown in FIG. 6 has the main body 15 as the printing stations 14Y, 14M, 14C and 14B using the offset printing apparatus shown in FIG.
And arranged around the impression cylinder 7 in Y, yellow (Y), M (magenta), and C, respectively.
The color printing is performed by using (cyan) and B (black) inks.

Each printing station 14Y, 14M, 14
C and 14B have the same configuration.
This is shown in FIG. As shown in FIG. 7, as in the first embodiment, the printing station 14Y includes a plate cylinder 1 having a surface mainly composed of a thermally responsive material such as titanium oxide or zinc oxide, and a plate cylinder 1 having a hydrophobic surface. A high-temperature heating unit 2 for heating to a high-temperature hydrophilicity-expressing temperature higher than the hydrophilicity-expressing temperature; a heat-sensitive recording unit 5 for performing heat-mode drawing on the plate cylinder 1 hydrophilicized by high-temperature heating; An ink / fountain solution supply unit 3 for supplying ink and fountain solution to the plate cylinder 1 on which an image is drawn, an ink washing unit 4 for removing ink remaining on the plate cylinder 1 after printing is completed, Impression cylinder 7 as an intermediate for transferring the retained ink to paper
And a blanket 6 that comes into contact with. Also,
A cooling unit 19 composed of, for example, a water-cooled jacket for forcibly cooling the plate cylinder after high-temperature heating may be provided.

Note that the printing stations 14Y, 14M,
Since the operations of 14C and 14B are the same as those of the offset printing apparatus shown in FIG. 2 described above, detailed description will be omitted. In the third embodiment, each printing station 14Y,
The colors of the inks supplied in the ink / fountain solution supply units 14M, 14C, and 14B are Y (yellow), M (magenta), C (cyan), and B (black), respectively.
Is different.

Next, the operation of the third embodiment will be described. First, the printing stations 14Y, 14M, 14
In C and 14B, the plate cylinder is heated to a high temperature not lower than the intermediate heating temperature by a high-temperature heating unit to make the entire surface hydrophilic, and then an image representing each color is rendered in a heat mode by a heat-sensitive recording unit at a hydrophobic expression temperature. I do. Then, the inks of the respective colors Y, M, C, and B are supplied from the ink / fountain solution supply units of the printing stations 14Y, 14M, 14C, and 14B, and the printing stations 14Y, 14M, and 14B are supplied.
The ink is held on the plate cylinder 1 of C and 14B. Then, FIG.
The paper is supplied as shown by the arrow C in FIG.
The M, 14C, and 14B inks are transferred to paper. That is, the Y ink is transferred at the printing station 14Y, the M ink is transferred at the printing station 14M, the C ink is transferred at the printing station 14C, and the B ink is transferred at the printing station 14B.
Is transferred. As a result, a color image is printed on the sheet.

After printing, each printing station 14Y,
The ink remaining on the plate cylinder is removed by the ink cleaning sections 14M, 14C and 14B. Thereafter, the plate cylinder is heated to a high temperature under the same conditions as described above, whereby the plate cylinder returns to a state before drawing in the heat mode.

In the second and third embodiments, the four printing units 11Y, 11M, 11C,
11B or four printing stations 14Y, 14
Although color printing is performed using M, 14C, and 14B, color printing may be performed by providing five or more printing units or printing stations.

In the first to third embodiments, the plate cylinder 1 is used. However, the present invention is not limited to this, and offset printing can be performed using a sheet-like printing original plate. It goes without saying that the present invention can be applied even if it is performed.

In the first to third embodiments, the ink washing unit 4, the ink / fountain solution supply unit 3, and the thermal recording unit 5 are arranged clockwise from the high-temperature heating unit 2. It is not limited to this, and can be arranged in any order.

Further, in each of the above embodiments and examples, an example using titanium oxide and zinc oxide has been described. However, the present invention is not limited to this, and any of the above-mentioned heat-responsive metal oxides or Metals can be used.

[0139]

The heat-responsive substance of the present invention, in particular, a printing plate having the heat-responsive metal and metal oxide described in the specification as an image forming layer, is heated to a high-temperature hydrophilicity developing temperature to make the surface hydrophilic. As a property, the printing method of making a printing plate by performing drawing in a heat mode at the surface at which hydrophobicity is exhibited on the surface to create a printing plate does not require processing such as development, and can directly create a printing plate, and after printing is completed. In addition, the printing plate can be reused by removing the printing plate ink to regenerate the printing plate. In addition, the original plate is mounted on the plate cylinder of a printing press, and a simple and inexpensive offset is performed on the printing press using a printing device that performs hydrophilicity, heat mode drawing, ink / fountain solution supply, and regenerating the original plate after printing. Printing can be performed.

[Brief description of the drawings]

FIG. 1 is a diagram showing the relationship between temperature and contact angle on the surface of titanium oxide according to the present invention.

FIG. 2 is a diagram illustrating a configuration of an offset printing apparatus according to the first embodiment of the present invention.

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

FIG. 4 is a diagram illustrating a detailed configuration of a thermal recording unit.

FIG. 5 is a diagram illustrating a configuration of an offset printing apparatus according to a second embodiment of the present invention.

FIG. 6 is a diagram illustrating a configuration of an offset printing apparatus according to a third embodiment of the present invention.

FIG. 7 is an enlarged view of a main part of FIG. 6;

[Explanation of symbols]

 Reference Signs List 1 plate cylinder 2 high temperature heating unit 3 ink / fountain solution supply unit 4 ink washing unit 5 thermal recording unit 6 blanket 7 impression cylinder 8 12, 15 body 9 cooling unit 11Y, 11M, 11C, 11B printing unit 14Y, 14M, 14C , 14B printing station 18 thermal head 19 thermal head drive 20 editing / layout 21 infrared laser light source 22 infrared laser light source drive S image signal

Continued on the front page (72) Inventor Takashi Nakamura 798 Miyadai, Kaisei-cho, Ashigara-gun, Kanagawa Prefecture Inside Fujisha Shin Film Co., Ltd. (Ref.)

Claims (15)

[Claims] 1. A printing original plate is heated at a high temperature at which hydrophilicity is exhibited to make its surface hydrophilic, and then the original plate is subjected to heat mode drawing at a temperature at which hydrophobicity is exhibited to form a hydrophobic image area. And printing the image area by contacting the image area with a printing ink to form a printing surface in which the image area has received the ink. 2. The high-temperature hydrophilicity developing temperature is 200 ° C. or higher, and the hydrophobicity developing temperature is 50 to 250 ° C. and lower than the high-temperature hydrophilicity developing temperature. Offset printing method. 3. The method according to claim 1, wherein after the ink remaining on the printing plate used for printing is removed by washing, the operation according to claim 1 or 2 is repeated using the printing original plate. The printing method according to claim 1. 4. The surface of a printing original plate corresponds to any one of the third to fourth tables of the periodic table.
6. The composition according to claim 6, wherein the metal belongs to six periods and is at least one selected from the group consisting of a metal selected from elements other than Group 0 and Group VIIA (halogen element) and an oxide of the metal. The offset printing method according to any one of claims 1 to 3. 5. The surface of a printing plate is made of TiO._Two, RTi
O_Three(R is an alkaline earth metal atom), AB_2-xC_xD
_3-xE_xO_Ten(A is a hydrogen atom or an alkali metal atom, B
Is an alkaline earth metal atom or a lead atom, C is a rare earth atom,
D is a metal atom belonging to Group 5A element of the periodic table, and E is the same
A metal atom belonging to Group 4A element, x is any number from 0 to 2
Value), SnO_Two, Bi_TwoO_Three, SiO_Two, GeO
_Two, Al _TwoO_Three, ZnO and Fe_TwoO_ThreeGold selected from
Be composed of at least one of the group oxides
The off-state according to any one of claims 1 to 5, characterized in that:
Set printing method. 6. The printing original plate is made of aluminum,
The offset printing method according to any one of claims 1 to 5, wherein the offset printing method is configured by at least one of a metal or a metal alloy selected from iron, copper, silicon, nickel, germanium, zinc, and tin. . 7. The image forming apparatus according to claim 1, wherein the drawing in the heat mode is performed by one of a drawing unit selected from a thermal transfer recording head and light-to-heat conversion type radiation.
7. The offset printing method according to any one of 6. 8. The method according to claim 1, wherein the heating temperature for hydrophilizing the surface of the printing original plate is 300 to 700 ° C.
8. The offset printing method according to any one of items 1 to 7, 9. The offset printing method according to claim 1, wherein drawing in a heat mode applied to the hydrophilic printing plate is performed in the presence of an organic compound. 10. The method according to claim 1, wherein the organic compound present in the drawing in the heat mode is at least 1 m at a temperature of 400 ° C.
The offset printing method according to claim 9, wherein the organic compound has a vapor pressure of mHg or more and is stable at a high temperature at which hydrophilicity is exhibited. 11. The organic compound present in the drawing in the heat mode is an organic compound having a boiling point in the range of 30 to 400 ° C. and being stable at a high hydrophilicity developing temperature. 11. The offset printing method according to item 10. 12. An offset printing apparatus used in the method according to any one of claims 1 to 11, wherein: an original plate mounting section for mounting a printing original plate; Heating means for heating to make the surface hydrophilic, drawing means for performing heat mode drawing on the original plate at a temperature at which hydrophobicity is developed to form a hydrophobic image area, and supplying printing ink to the image area An offset printing apparatus, comprising: an ink supply unit that forms a printing surface in which an image area receives ink, and a printing unit that performs printing by bringing the printing surface into contact with the surface to be printed. 13. The offset printing apparatus according to claim 12, further comprising means for removing ink remaining on the printing plate after printing is completed. 14. The offset printing apparatus according to claim 12, wherein at least the exposing means, the drawing means, the ink supply means, and the ink removing means are arranged around the plate cylinder. 15. The printing original plate forms a part of a plate cylinder, and at least an exposure unit, a drawing unit, an ink supply unit, and an ink removal unit are arranged around the plate cylinder. The offset printing apparatus according to any one of claims 12 to 14, wherein