JP2000211095A - Offset printing method, printing original plate and printing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and apparatus for negative type offset printing by carrying out plate making readily without the necessity of alkaline developer, and having a practical printing image quality of high discrimination in the image part and nonimage part of a printing surface, and also enabling printing paper to be used repeatedly. SOLUTION: The method and apparatus for offset printing is effected such that a printing original plate being composed in its surface of a heat reactive substance such as titanium oxide and zinc oxide is heated at a hydrophobic developing temperature to make a surface hydrophobic before being subjected to image-like heating at a high temperature hydrophilic developing temperature to form an image like distribution of a hydrophilic area and hydrophobic area; which thereby printing ink is accepted in the hydrophobic area. Furthermore, this is the reusing method of a printing original plate employing the printing original plate again by cleaning and removing ink staying on the face of a print-finished printing plate, thus, in particular, improving printing quality by making a hydrophobic property in the presence by a volatile organic compound.

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 receiving capacity of the image area and the ink repulsion of the non-image area, thereby improving the printing durability. Then, the printing surface is refined, and a printing image 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] In view of the above background, a method of manufacturing a simple printing plate has been developed in which a developing step using an alkali developing solution after image exposure is omitted. 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 a printing quality of a practical level in which the printing quality is improved, and which can use a printing plate repeatedly. 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. Further, the present invention intends to provide a printing method which is a negative type plate making method and satisfies the above object.

[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 The present inventors have found the possibility of solving the above-mentioned problem by applying the present invention to a negative-type printing image forming system used for erasing an image on a printing plate after printing is completed, and based on this finding, completed the present invention. That is, the present invention is as follows.

1. The printing plate is heated at the temperature at which hydrophobicity is developed to make the surface hydrophobic, and then the surface is heated imagewise at the temperature at which high hydrophilicity is developed to form an image-like distribution of hydrophilic regions and hydrophobic regions. An offset printing method comprising: contacting a hydrophobic area with a printing ink to form a printing surface in which the area has received the ink; and performing printing.

2. 2. The offset printing method according to the above item 1, wherein the hydrophobicity development temperature is 50 to 250 ° C.

[0015] 3. After washing and removing the ink remaining on the printing plate surface used for printing, the printing plate is used as a printing plate and the operation described in the above item 1 or 2 is repeated to perform printing. The printing method described.

4. 4. The offset printing method according to any one of the above items 1 to 3, wherein when the printing original plate is heated at a temperature at which hydrophobicity is developed, heating is performed in the presence of an organic compound.

5. The organic compound to be present when heated at the hydrophobic development temperature is at least one at 400 ° C.
5. The offset printing method according to the above item 4, wherein the organic compound has a vapor pressure of not less than mmHg and is stable at a temperature at which hydrophobicity is developed.

6. 6. The offset printing method according to the above item 4 or 5, wherein the organic compound to be present when heated at the hydrophobic development temperature has a boiling point in the range of 30 to 400 ° C.

[7] At least one of the heating performed at the hydrophobic development temperature and the imagewise heating performed at the high hydrophilic development temperature is performed by a heating unit selected from a thermosensitive recording head and a photothermal conversion type radiation. 7. The offset printing method according to any one of 6.

[8] The surface of the printing original plate belongs to the third to sixth periods of the periodic table, and includes a metal selected from metal 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 the above items 1 to 7, wherein the offset printing method comprises at least one.

9. 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 , ZnO and FeO _x (x = 1 to 1.
(5) The offset printing method according to any one of (1) to (8) above, wherein the offset printing method is configured by at least one of metal oxides selected from iron oxides.

10. The surface of the printing original plate is composed of at least one of a metal selected from aluminum, iron, copper, germanium, nickel, zinc, tin and silicon or an alloy thereof, Item 2. The offset printing method according to Item 1.

11. An offset printing apparatus used in the method according to any one of the above 1 to 10, wherein a plate cylinder on which a printing original plate is mounted, and the surface of the printing plate are heated to a hydrophobic expression temperature to make the surface hydrophobic. Heating means, and drawing means for applying an imagewise distribution of the hydrophilic area and the hydrophobic area by applying imagewise heating to the original plate at a high hydrophilicity developing temperature, and supplying a printing ink to the hydrophobic area. An offset printing apparatus, comprising: an ink supply means for forming a printing surface in which the area has received ink; and a printing means for performing printing by bringing the printing surface into contact with the surface to be printed.

12. 12. The offset printing apparatus according to the above item 11, further comprising means for removing ink remaining on the printing plate after printing is completed.

13. A heating means for heating at least at a hydrophobic development temperature, a drawing means for imagewise heating at a high hydrophilicity development temperature, an ink supply means and an ink removal means are arranged around the plate cylinder. 11 above
Or the offset printing apparatus according to 12.

14. The printing original plate constitutes a part of the plate cylinder, and heating means for heating at least at a hydrophobic expression temperature,
14. The printing method according to any one of items 11 to 13, wherein a drawing unit, an ink supply unit, and an ink removal unit that perform imagewise heating at a high hydrophilicity developing temperature are disposed around the plate cylinder. An offset printing apparatus as described in the above.

15. The heating means for heating the printing original plate at the temperature at which hydrophobicity is exhibited to make the surface hydrophobic is provided with an organic compound vapor supply means so that the vapor of the organic compound is in contact with the surface of the original plate. 15. The offset printing apparatus according to any one of items 11 to 14.

The present invention has been made based on the discovery of a unique thermal response behavior of the surface properties of a specific substance (mainly the above-mentioned metal oxides and metals). That is, the clean surface of this particular substance is inherently hydrophilic to varying degrees, but at a moderate temperature (hereinafter referred to as the "hydrophobic expression temperature").
Heating at high temperature (hereinafter referred to as "high hydrophilicity expression temperature"), it becomes hydrophilic again. It is based on the discovery that it works. The present invention is a negative offset printing method and a printing apparatus that effectively utilize the thermal response behavior.

If this property is utilized, as a first step, the surface of a specific substance having the above-mentioned properties is uniformly heated to a temperature at which hydrophobicity is developed to make the surface of the substance a hydrophobic region. In two steps, the surface is heated imagewise at the temperature of developing hydrophilicity to make the heated area hydrophilic, forming an imagewise distribution of hydrophilic and hydrophobic areas, and then as a third step in the hydrophobic area. This is a method of performing offset printing by holding a dampening solution in a hydrophilic region of a printing ink. Further, after the printing is completed, the used printing plate ink is washed and removed, and the printing plate is uniformly heated again to the temperature at which the hydrophobicity is exhibited. Since a functional surface is obtained, it can be used again as a printing plate in the above-described plate making and printing processes. The above to be used in the present invention ~
Substances with the characteristics described above are both practically sufficient due to the hysteresis effect even at room temperature, for both surfaces that have been rendered hydrophobic by heating at the temperature at which hydrophobicity develops and hydrophilic surfaces that have been imagewise heated at the temperature at which hydrophilicity develops. The hydrophobic or hydrophilic property is maintained for a long time. 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 heat-responsive behavior will be described later in more detail.

[0030]

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,
Although the material having the characteristics described above is defined, the thermally responsive material defined in this definition is widely used in metals and metal oxides, and includes materials belonging to ceramics and semiconductors. Thermally responsive ceramics are composed of composite metal oxides, and most of thermally responsive semiconductors are based on genuine semiconductors such as silicon and germanium, whose bases and conductors are similar, and vanadium oxide and copper oxide, which depend on impurity levels. And found in both pseudo semiconductors. These ceramics and semiconductors are the same as other heat-responsive metals and metal oxides in terms of the heat-responsive properties of the substances used in the present invention. It will be described below in that order.

The above-mentioned metal oxides which have the property of being rendered hydrophobic by appropriate heating and becoming hydrophilic upon further heating and which can be used as a thermoresponsive metal oxide exhibiting a hysteresis phenomenon include various forms of It is found in metal oxides, and may be either a single metal oxide or a composite oxide.In the latter case, solid solutions, mixed crystals, polycrystals, amorphous solid solutions, and metal oxide microcrystals All of the mixtures have this property. A metal oxide having such characteristics is empirically found as an oxide of a metal element belonging to the third to sixth periods excluding the 0th and VIIA (halogen element) groups in the periodic table. The metal and the metal oxide must not be excessively dissolved in fountain solution when used as a printing plate.
10 mg or less per milliliter, preferably 5 mg
Or less, more preferably 1 mg or less.

Among the "thermally responsive metal oxides", titanium oxide and zinc oxide are preferable, and these will be described first. These can all be used as the printing plate material of the present invention. As the titanium oxide, one made by any known method such as sulfuric acid heating and sintering of ilmenite or titanium slag, or heat chlorination followed by oxygen oxidation can be used. 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 coating a dispersion of titanium oxide microcrystals or zinc oxide microcrystals on the original plate of a printing 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 a printing original plate by a method such as vapor deposition, sputtering, ion plating, or CVD, 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 method of applying the above-mentioned titanium oxide microcrystals is, for example, a method of applying an amorphous titanium oxide microcrystal dispersion, followed by firing to form an anatase or rutile type crystal 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 A method of dispersing and applying a polymer binder capable of 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, polyethylene naphthalate, polyvinyl alcohol, partially saponified polyvinyl alcohol, polystyrene and the like. Is preferred, and these resins may be used as a mixture.

In performing the above-mentioned vacuum deposition of titanium oxide,
Is usually used as a heat source for evaporation heating in vacuum evaporation equipment.
And place it in a vacuum of 10^-Five-10^-810 Torr total gas pressure^-2
-10 ^-FiveTorr, oxygen partial pressure ratio should be 5 ~ 90%
While evaporating titanium metal, titanium oxide
A deposited thin film of tan is formed. Also, for sputtering
In some cases, for example, a titanium metal target
And set Ar / O_TwoThe ratio is 60/40 (molar ratio)
Gas pressure to 5 × 10^-3After adjusting to Torr,
Apply RF power 200W and perform sputtering
A titanium oxide thin film is formed on a 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, a method of forming an oxide film by electrolytically oxidizing the surface of a metal zinc plate and a method of forming a zinc oxide film by vacuum deposition, sputtering, ion plating, CVD, or the like are 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 coating 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 remarkable purity as when zinc oxide is used in an 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, if 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%.

Next, another compound that can be used in the present invention, that is, a metal titanate represented by the general formula RTiO ₃ will be described. In the general formula RTiO ₃ , R is a metal atom belonging to an alkaline earth element of the periodic table such as magnesium, calcium, strontium, barium, beryllium, and particularly preferably strontium and barium. Also, 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 , general formula AB _2-x C _x D _3-x E
The compound represented by _{x O 10, SiO 2, SnO} 2, B
i ₂ O ₃ , GeO ₂ , Al ₂ O ₃ , FeO _x (x = 1 to
The above method of providing titanium oxide and zinc oxide can be used for forming any thin film of iron oxide represented by 1.5). That is, a method of applying a dispersion of the heat-responsive metal oxide fine particles to a printing plate precursor, a method of applying and then firing to reduce or remove the binder,
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, after applying an organic compound such as an alcoholate of a metal element on the original plate, hydrolyzing it, and further performing firing oxidation. Any known method such as a method of forming a metal thin film having an appropriate thickness, and a method of heating and spraying an aqueous solution of a hydrochloride or a nitrate containing the above-mentioned metal can be used.

For example, in order to apply the barium titanate fine particles by the application method described above, 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. By this method, a thin film of magnesium titanate, calcium titanate, strontium titanate or an intermolecular compound or a mixture thereof can be similarly formed in addition to barium titanate. Further, “FeO _x ” described above and also used in other parts of the specification is FeO, Fe ₂ O ₃ , Fe
It is a generic term for iron oxide-based compounds such as ₃ O ₄ .

Similarly, CsLa ₂ NbTi ₂ O ₁₀ fine particles can be coated by the above-described coating method. CsLa ₂ NbTi ₂ O ₁₀ fine particles correspond to the stoichiometry of Cs ₂ CO ₃ , La ₂ O ₃ , NbO ₅ , TiO 2
Finely pulverize ₂ in a mortar and put in a platinum crucible, 130 ° C
For 5 hours, and after cooling, put in a mortar and pulverize to fine particles of several microns or less. This CsLa ₂ NbT
The i ₂ O ₁₀ fine particles were dispersed in a binder in the same manner as the above barium titanate, and coated to form a thin film. This method is not limited to CsLa ₂ NbTi ₂ O ₁₀ type fine particles.
_{Ca 1.5 La 0. 5 Nb 2.5 Ti} 0.5 O 10, HLa 2 Nb
Ti ₂ O _10, etc. described above _{AB 2-x C x D 3-} x E x O 10,
(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, using a barium titanate target to raise the temperature of the support for the deposited film to 450 ° C.
By keeping the above conditions and performing RF sputtering in an argon / oxygen mixed atmosphere, a barium titanate crystal thin film can be obtained. 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 a tin oxide thin film is provided, a substrate temperature of 120
C in a mixed atmosphere of 50/50 argon / oxygen ratio
By performing F sputtering, a thin film of the tin oxide crystal for the purpose is obtained.

Method using the above metal alcoholate
Also, the desired thin film can be formed without using a binder
Is the way. To form a barium titanate thin film
Mixed alcohol of lium ethoxide and titanium butoxide
Solution on the surface with SiO_TwoOn a silicon substrate with
Cloth, after hydrolyzing the surface, 200 ℃ or more
Heating to form barium titanate thin film
It is. The method of this method is also similar to the other RTiO described above._Three(R is
Alkaline earth metal atom), AB_2-xC_xD_3-xE _xO_Ten
(A, B, C, D, and E represent the contents of the above definitions, respectively.
), SnO_Two, SiO_Two, Bi_TwoO_Three, GeO_Two, A
l_TwoO_ThreeAnd FeO_x(X = 1 to 1.5)
Can be applied.

As described above, the method of forming a metal oxide thin film exhibiting a thermoresponsive function can also form a binder-free thin film. In order to form a thin film of SnO _2, an aqueous solution of hydrochloric acid of SnCl ₄ can be sprayed onto the surface of quartz or crystalline glass heated to 200 ° C. or higher to form a thin film. This method also uses SnO ₂ thin film,
RTiO ₃ (R is an alkaline earth metal atom), A
_{B 2-x C x D 3} -x E x O 10 (A, represents B, C, D, the contents of the definition of each E the), SiO _2, SnO _2,
Bi ₂ O ₃ , GeO ₂ , Al ₂ O ₃ and FeO _x (x =
1 to 1.5) can be applied to the formation of any thin film of iron oxide.

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 heat-responsive 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%.

The description of the “thermally responsive metal oxide” and the method of providing the same on the surface of the original plate has been completed, and the “thermally responsive metal” will now be described. Any metal that can be used in the present invention as a heat-responsive metal has the property of becoming hydrophobic by moderate heating, has the property of becoming hydrophilic when further heated, and is a metal that exhibits a hysteresis phenomenon. However, a metal having such characteristics is empirically found in a metal element belonging to the third to sixth periods except for the group 0 and the group VIIA (halogen element) in the periodic table. Also,
Metals having thermal response characteristics found among the metals in the above range of the periodic table, even if a single composition metal,
Even 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. Also, as seen in stainless steel (hereinafter referred to as SUS),
A passive oxide film may be formed on the surface. Further, a process of forming an oxide film positively, such as anodic oxidation, may be performed. Further, there is no particular restriction on the purity of a single kind of metal or alloy, and the purity of a single kind of metal or alloy can be applied to the present invention as long as it is used for ordinary general use. Also,
As described in the section on metal oxides, it is needless to say that it is desirable that metals have low solubility in water for repeated reuse of printing original plates. There is no problem if the amount dissolved per 100 ml of water is 1 mg / L or less.

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 form of use of the heat-responsive metal, a metal plate can be used as it is, or a suitable plastic film or another metal plate is used as a support and provided on the support 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. Above, the thermoresponsive substance used in the present invention,
The description of the heat-responsive metal oxide and the metal is particularly ended.

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 that is not thermally decomposed even at the temperature at which hydrophobicity is developed 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 (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. Among these, an aluminum plate which has good dimensional stability and is relatively inexpensive, Polyimide films that are highly stable to operation are particularly preferred.

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 used, and thus cannot be specified unconditionally. In general, the concentration of the electrolyte is a 1 to 80% by weight solution, and the liquid temperature is 5 to 70 ° C.
It is appropriate that the current density is 5 to 60 A / dm ² , the voltage is 1 to 100 V, and the electrolysis time is 10 seconds to 5 minutes. If the amount of the anodic oxide film is less than 1.0 g / m ² , the printing durability is insufficient or the non-image area of the lithographic printing plate is easily scratched, and the ink adheres to the scratched area during printing. So-called "scratch dirt"
Is more likely to occur.

The configuration of the negative printing plate using the thermally responsive material used in the printing method of the present invention has been described above. It is described using.

First, the thermal responsiveness of the surface of the thermally responsive substance is further shown in the figure. 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 at a temperature of 210 ° C., and further increases the contact angle.

As shown in this example of titanium oxide, the surface temperature is increased from room temperature, and becomes hydrophobic when it reaches the region of “hydrophobic expression temperature”. It is the property of the thermo-responsive material that it becomes hydrophilic again. By grasping this characteristic, heating is performed within the range of the appropriate hydrophobic expression temperature avoiding the high temperature hydrophilic expression temperature to make the entire surface hydrophobic, and the surface has an image-like high temperature hydrophilic expression temperature. When heating is performed, a negative type hydrophobic / hydrophilic image-like distribution in which the image-wise heated area becomes hydrophilic is obtained. By utilizing the thermal response, heating adapted to the temperature at which hydrophobicity is developed and imagewise heating at the temperature at which hydrophilicity is developed, a highly uniform hydrophobic surface and an excellent discrimination effect between hydrophobicity and hydrophilicity are obtained. The feature of the present invention is that it is a negative type plate making method having excellent reproducibility not affected by the history during storage of the original plate, and these features are combined with high discriminability between the image area and the non-image area. Printing plates can be manufactured with good reproducibility.

A further advantage is the simplicity that a printing plate can be prepared only by two-step heat treatment of uniform heating and imagewise heating. It should be further added that the presence of an organic compound (described later) in an atmosphere at a hydrophobic development temperature promotes hydrophobicity, further improving the effect of discriminating between hydrophilicity and hydrophobicity, and improving the quality of the printing plate. That is what you can do.

In the region of “hydrophobic expression temperature”, specifically, the decrease in the contact angle on both sides of the maximum value of the contact angle is 20%.
This indicates an area within a degree, which corresponds to a practical hydrophobic area for receiving ink. In the experimental example of FIG. 1, the maximum value of the contact angle is 50 degrees, and the region of the hydrophobic expression temperature of 20 degrees on both sides is 155 to 240 ° C. In general, the type of the thermoresponsive substance, the heating rate, and the heating rate It depends on the atmosphere. Also,
Even at the same heating rate and the same heating atmosphere, the maximum value of the contact angle differs depending on the thermally responsive material such as titanium oxide, zinc oxide, barium titanate, and the temperature range corresponding to the range of 20 degrees on both sides also changes. This temperature range changes even if the heating rate is increased. Despite these slight differences, the hydrophobicity development temperature is generally 50-250 ° C.
And especially in the temperature range of 100-250 ° C. By performing uniform heating in this temperature range, it is possible to have a uniform and high level of surface hydrophobicity,
Therefore, the discriminability between the image portion and the non-image portion can be increased, and the quality of the printed surface can be improved.

The means for heating to the temperature at which hydrophobicity is exhibited include electric heating means such as a nichrome wire or a heating resistor, a solid laser emitting infrared light, or a semiconductor laser emitting infrared light, an infrared lamp, a xenon discharge lamp. And a semiconductor laser that emits light in the visible region (when a light-to-heat conversion function is incorporated in a heated portion), and a light-to-heat conversion heating device that emits flash light by discharging from a large-capacity capacitor. Among them, the electrothermal heating means and the infrared lamp are preferable because the temperature can be easily controlled within the temperature range in which hydrophobicity is exhibited, a uniform heating surface can be widely obtained, and the cost is low. Further, the entire surface may be made hydrophobic by scanning the thermal recording head.

When the organic compound vapor is present in the heating atmosphere as described above when heating to the hydrophobic development temperature, the rate of hydrophobicity and the maximum contact angle increase, and the temperature and the temperature at which the contact angle becomes maximum are increased. The temperature region that becomes hydrophobic also changes.
As a result, the effect of distinguishing between 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 advantageous effects are those which have a vapor pressure of at least 1 mmHg at a temperature of 400 ° C. and are stable at a temperature at which the vapor pressure is 1 mmHg. That is, when an organic compound having such a vapor pressure is present in the heated atmosphere, the discrimination between hydrophilicity and hydrophobicity is improved. More preferably, it is an organic compound which has a vapor pressure of at least 1 mmHg at a temperature of 300 ° C. and is stable at a temperature at which the vapor pressure becomes 1 mmHg. More preferably, it is an organic compound having a boiling point of 30 to 400 ° C. and stable in a temperature range of 30 to 400 ° C., and a particularly preferable boiling point is 50 to 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, and phenethylamine; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and benzophenone; Ethers such as methoxybenzene, ethoxybenzene, methoxytoluene, lauryl methyl ether, stearyl methyl ether and stearyl amide;
Amides such as benzoylamide and acetamide are exemplified.

Further, oils and fats such as linseed oil, soybean oil, poppy oil, and safflower oil 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 having a boiling point within the above preferred range, such as ethylene glycol monoethyl ether, cyclohexanone, methyl cellosolve, butyl cellosolve, cellosolve acetate, 1,4-dioxane, dimethylformamide and acrylonitrile can also be used.

Preferred organosilicon compounds are organopolysiloxane compounds typified by dimethyl silicone oil, methylphenyl silicone oil and the like, especially organopolysiloxanes having a polymerization degree 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 carbon atom having 7 to 18 carbon atoms.
An aralkyl group of 18 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 above-mentioned aryl group, aralkyl group and 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, a dialkoxysiloxane group having an alkoxy group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, and phenyl. A repeating unit containing at least one of an alkoxyphenylsiloxane group having a group and an ethoxymethoxysiloxane group or a methoxyethoxysiloxane group, and having a degree of polymerization of 2 to 12, more preferably 2
10 to 10 polyorganosiloxanes. The terminal group is an alkyl group having 1 to 5 carbon atoms, an amino group, a hydroxy group, a hydroxyalkyl group having 1 to 5 carbon atoms or an alkoxy group having 1 to 5 carbon atoms. More preferred terminal groups are
A methyl group, an ethyl group, an isopropyl group, an n-propyl group, an n-butyl group, a t-butyl group, a methoxy group and an ethoxy group. Among them, preferred siloxane compounds are dimethylpolysiloxane having a polymerization degree of 2 to 10, dimethylsiloxane-methylphenylsiloxane copolymer having a polymerization degree of 2 to 10, and dimethylsiloxane-diphenylsiloxane copolymer having a polymerization degree of 2 to 8 Dimethylsiloxane-monomethylsiloxane copolymer having a polymerization degree of 2 to 8; the terminal of these polysiloxane compounds is a trimethylsilane group. In addition, 1,3-bis (3-aminopropyl) tetramethyldisiloxane, 1,5-bis (3-
Aminopropyl) hexamethyltrisiloxane, 1,3
-Dibutyl-1,1,3,3-tetramethyldisiloxane, 1,5-dibutyl-1,1,3,3,5,5-hexaethyltrisiloxane, 1,1,3,3,5,5 -Hexaethyl-1,5-dichlorotrisiloxane, 3-
(3,3,3-trifluoropropyl) -1,1,3
3,5,5,5-heptamethyl-trisiloxane, decamethyltetrasiloxane and the like.

Particularly preferred general-purpose 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 Industry Co., Ltd.) and methyl hydrogen silicone oil (commercially available, for example, silicone KF99 (Shin-Etsu Chemical Co., Ltd.)).

Other examples include silane compounds such as n-decyltrimethoxysilane, n-decyltri-t-butoxysilane, n-octadecyltrimethoxysilane, n-octadecyltriethoxysilane, and dimethoxydiethoxysilane.

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 inside a jacket of a heating section provided so as to be in contact with the surface of the original plate, and the organic compound is heated during the heating time. The compound vapor may be present in the mantle. Alternatively, paper, cloth, zeolite, diatomaceous earth, or the like impregnated with an organic compound may be inserted into the jacket and heated.

The heating method and scanning at the temperature at which the hydrophobicity is developed have been described above, and the application of the printing image by imagewise heating at the high temperature at which the surface has been rendered hydrophobic at the high hydrophilicity is described. Heating means for forming a hydrophilic region on a printing plate include a solid-state laser that emits infrared light, or a semiconductor laser that emits infrared or visible light, an infrared lamp, a xenon discharge lamp, and a large-capacity capacitor. A light heating method such as a light-to-heat conversion drawing mechanism that emits flash light by discharge from the substrate, and a contact heating method such as a thermal recording head using a thermal melting type and sublimation type thermal dye transfer are used as the other. In order to adjust the heating temperature to a range of high-temperature hydrophilicity expression temperature higher than the hydrophobicity expression temperature, it is necessary to control the intensity of light used for heating or to control the power supply to the heating head for thermal recording. The method is taken.

The image heating of the light heating system may be any of a surface exposure system and a scanning system. In the former case, an infrared irradiation method or 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 is used. When a surface exposure light source such as an infrared lamp is used, the preferable exposure amount changes depending on the illuminance, but usually, the surface exposure intensity before being modulated with a print image is 0.1 to 10 J / cm ² . Preferably within the range,
More preferably, it is in the range of 0.3 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 μsec to 10 msec, preferably 0.1 μsec.
It is preferable to select the exposure illuminance so that the above-described exposure intensity can be obtained by irradiation of 1 μsec to 1 msec. When 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, that is, in the case of the scanning method, a method of modulating a laser beam with an image using an infrared laser light source and scanning the original plate is performed. Examples of laser light sources include semiconductor lasers, gas lasers, helium cadmium lasers,
An AG laser can be mentioned. 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. 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.

In the contact heating method, any known contact-type thermal recording apparatus, for example, a thermal recording head of a thermal melting type and a sublimation type thermal dye transfer method is used. These include a method in which a single thermal recording element is driven two-dimensionally, a method in which an array of linearly arranged thermal recording elements is scanned in a perpendicular direction and drawing, or a high-speed drawing method using a two-dimensionally arranged recording element. A known thermal recording element can be used. In the present specification, the heat-sensitive recording and the heat recording are synonymous and are used for image-like recording.

In the above, the heat response characteristic and the heat response type material of the printing original plate and the heating method for forming an image using the same have been described. Next, a printing method and an apparatus for mounting the original plate will be described.

The original printing plate is formed by forming a negative type lipophilic / hydrophilic image-like distribution on the surface of a heat-responsive material.
It can be sent to the offset printing process without any development processing. 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. It is also an advantage that printing is easily performed from the simple image recording means as described above.

The imagewise high-temperature heating area of the lithographic printing plate obtained from the heat-responsive material is sufficiently hydrophilic. Post-treatment with a desensitizing solution containing a starch or a starch derivative. 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, it is more preferable that the application amount is made uniform by using a squeegee or a squeegee roller after the application. In general, it is appropriate that the application amount of the surface conditioning liquid is 0.03 to 0.8 g / m ² (dry weight).
The lithographic printing plate obtained by such a process is applied to an offset printing machine or the like, or is made on a printing machine,
Used for printing many 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 at the temperature at which hydrophobicity is developed by the above-described method to uniformly restore the hydrophobicity over the entire plate surface. This heating operation may be performed at any time between washing and removal of the printing ink and imagewise irradiation with actinic light in the next plate-making operation. It is preferable to carry out this step because the influence of the history during storage of the original plate can be eliminated.

Although the number of reproducible printings 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 constituent materials of the printing original plate and the plate making operation in the present invention have 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.
In the description after FIG. 2, the former, which remarkably demonstrates the simplicity of the present invention, will be described as an example, that is, an example in which a printing original plate is fixed on a plate cylinder 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 heat-responsive material such as titanium oxide or zinc oxide on the surface thereof, and exhibiting hydrophobicity with respect to the plate cylinder 1. Heating unit 2 that heats the surface to make the entire surface of the original plate hydrophobic.
And a high-temperature heating recording section 5 for performing imagewise heating at a high-temperature and hydrophilicity developing temperature on the plate cylinder 1 which has been entirely made hydrophobic to form an imagewise distribution of hydrophilic regions and hydrophobic regions; Ink / fountain solution supply unit 3 for supplying ink and fountain solution to cylinder 1
And 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 and fed. And an impression cylinder 7 for holding the sheet. These members are accommodated in a main body 8. The main body 8 is provided with a film supply unit 10 for supplying a squirrel film 9 which has been printed and developed by printing a printing document, as described later.

The heating section 2 is equipped with an electric heater equipped with a temperature control device, and the surface of the plate cylinder is kept within the range of the hydrophobicity developing temperature. As this heating means, an electric heating method is suitable, but it is also possible to employ a uniform surface heating method and heat ray heating with an infrared lamp which is also easy to adjust the temperature, and to adopt the other heating methods described above. Can be.

FIG. 3 shows an embodiment of the heating unit 2 in which an organic compound vapor supply means for heating the surface of a printing original plate in an atmosphere containing organic compound vapor to promote hydrophobicity is provided. Department.

In FIG. 3, the organic compound vapor supply means 2
In 9, air is taken in from the air intake port 24, and is led through the cock 25 to the evaporation chamber 26 in which a separatory funnel type glass tube having an inner diameter of about 30 mm is arranged horizontally. The evaporating chamber is filled with an organic compound 27 (shown by oblique lines) so that the volume ratio becomes, for example, 50%.
After a necessary amount of the vapor of the organic compound is taken in while the air passes through the inside and the surface of the plate, it is guided to the surface of the printing plate on the plate cylinder 1, and drawing is performed in the mixed atmosphere of the air and the vapor. The structure is

The heating area inside the jacket of the heating section 2 is heated by the electric heater 31 and the evaporating chamber 26 is heated by the electric heater 30, and the heating temperature is determined by the temperature sensors 32 disposed in the heating area and the evaporating chamber 26, respectively. The temperature is controlled to a predetermined temperature by the temperature controller 33 and the temperature controller 34. Also,
The amount of vapor taken in by the organic compound 27 is an amount that is sufficient to enhance the hydrophobicity when the heating temperature of the printing original plate is set to a predetermined hydrophobic expression temperature in the control unit 34, and is the amount. The temperature of the evaporation chamber 26 is set as described above. For example, in the case of a low-boiling organic compound (for example, methyl ethyl ketone or methyl cellosolve) which is easy to volatilize, the temperature of the evaporating chamber does not need to be heated just by filling the organic compound 27 in the lower part of the evaporating chamber, but it is not sufficient. In the case of a compound having a slightly higher boiling point (e.g., hexylene glycol), air and organic compounds containing air having high porosity, such as silica earth, silica particles, and zeolite particles, are introduced together with the organic compound 27 into the evaporation chamber. Measures will be taken to increase the degree of contact. When the organic compound 27 is a solid such as naphthalene, the evaporant 26 is filled with an appropriate porosity. In the case of an organic compound having a higher boiling point, the temperature controller 3
4. A mechanism capable of adjusting the temperature inside the evaporation chamber 26 to a temperature suitable for evaporation by the electric heater 30 and the sensor 31. For example, when using silicone oil, diatomaceous earth impregnated with silicone oil is placed in contact with air in the lower half of the glass tube so that the volume ratio is 50%. At 24, the tube is heated by an electric heater 30 at room temperature, for example, to 190 ° C. while passing through the tube. Although not shown, air containing steam is naturally exhausted outside. If necessary, air purification is performed before exhausting. The original plate having its surface rendered hydrophobic in the heating unit 2 is subjected to imagewise heating at a high-temperature hydrophilicity developing temperature in a high-temperature heating recording unit 5.

Returning to FIG. 2, in the present embodiment, the high-temperature heating recording unit 5 uses a thermal recording head, but any other known contact heating drawing apparatus may be used. In this embodiment, a thermal recording unit in which a sialon abrasion protection layer is provided on a tantalum-silica heating resistor and arranged in a direction perpendicular to the rotation direction of the plate cylinder is used to rotate the plate cylinder. At the same time, heating drawing is performed on the plate cylinder surface. Since the thermal head reaches 450 ° by energizing for 20 msec, it is possible to perform drawing at a high hydrophilicity developing temperature. As the drawing method using contact heating, in addition to the two-dimensional drawing using the one-dimensional unit in the perpendicular direction scanning of this embodiment, a method such as a two-dimensional scanning method using a heating element or a one-dimensional block unit can be used.

As another embodiment of the high-temperature heating recording section 5, instead of a contact heating recording method such as a thermal recording head, a method of irradiating the surface of an original plate by carrying image information on photothermal conversion radiation is used. . Particularly preferred in this method is a heat mode drawing method using infrared laser light. FIG. 4 is a configuration example of an example of drawing by an infrared laser beam carrying image information in that example. The high-temperature heating recording unit (5 in FIG. 2) emits an infrared laser beam and irradiates the plate cylinder 1 with an infrared laser light source 21. A laser light source driving unit 22 for driving an infrared laser light source 21 based on the input image signal S to modulate the infrared laser light and draw on the surface of the plate cylinder 1
Consists of The light source 21 is configured to scan the plate cylinder 1 by moving the emitted infrared laser light relative to the plate cylinder 1 in the rotation axis direction of the plate cylinder 1, and to rotate the plate cylinder 1. Thus, the surface of the plate cylinder 1 is exposed to the modulated infrared laser light, the portion of the plate cylinder 1 not irradiated with the infrared laser light is made a hydrophobic non-image area, and the portion irradiated with the infrared laser light is The image is formed as a hydrophilic image area and is drawn in a negative type. Note that a semiconductor laser, a solid-state laser, or any other laser can be used as long as it emits infrared light. Needless to say, it is desirable that the original plate to be irradiated contains a light-absorbing light-absorbing substance.

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

Next, the operation of the first embodiment will be described. First, the surface portion of the plate cylinder 1 that passes while rotating the heating unit 2 that heats to a hydrophobic temperature changes from hydrophilic to hydrophobic by heating. The temperature of the heating section is controlled by the temperature control section 34 within the range of the hydrophobicity development temperature. When the organic compound is present in the heating atmosphere, the organic compound vapor is contained in the heating atmosphere by the organic compound supply means 29. The plate cylinder, whose entire surface has been made hydrophobic,
In the high-temperature heating recording section 5, the area heated by the contact heating by the thermal recording unit or the irradiation of the infrared laser modulated with image information is hydrophilic, and the area not heated is hydrophobic. A hydrophobic image-like distribution is obtained. When the imagewise heating at the high-temperature hydrophilicity developing temperature is completed, the ink and fountain solution are supplied to the plate cylinder 1 from the ink / fountain solution supply unit 3. As a result, the ink is held in the hydrophobic image area of the plate cylinder 1, and the fountain solution is held in the hydrophilic non-image area without holding the 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. Will be

After the printing is completed, the plate cylinder 1 is printed by the ink washing section 4.
The remaining ink is removed. Thereafter, the plate cylinder 1 is rendered hydrophobic through the heating section 2 having a hydrophobic temperature, whereby the image-like hydrophilic region of the plate cylinder 1 is erased, and the state returns to the state before high-temperature hydrophilicity heating.

As described above, according to the offset printing apparatus of the present invention, a negative-type printing screen is formed on the plate cylinder 1 only by forming a uniform hydrophobic surface by heating the entire surface and imagewise heating at a high hydrophilicity temperature. This makes it possible to perform offset printing that does not require development and maintains the sharpness of the printed surface. Further, since the plate cylinder 1 can be returned to the original state by washing the plate cylinder 1 and heating the whole surface again at the temperature at which hydrophobicity is exhibited, the plate cylinder 1 can be used repeatedly, thereby providing printed matter at low cost. You can do it. 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 heating section 2 at the hydrophobic temperature, the ink / fountain solution supply section 3, the ink washing section 4 and the high-temperature heating recording section 5 around the plate cylinder 1, the plate cylinder 1 is simply rotated. ,
Since the entire surface of the original plate can be made hydrophobic, imagewise irradiation with actinic light, supply of ink and dampening water, and ink washing after printing can be performed, the apparatus can be made compact, thereby saving energy. Space can be achieved.

Further, among the simple negative plate-making methods, the present invention in which the heating temperature is controlled to make the entire surface hydrophobic and then the imagewise heating is performed at the high-temperature hydrophilicity developing temperature is performed without or with the heating operation. Even if the heating temperature is not controlled, a highly uniform hydrophobic surface can be obtained compared to the method in which imagewise irradiation with actinic light is performed. Can be executed to simplify and speed up, and the reproducibility is good without being affected by the history. As a result, there is an advantage that a printing plate having high discrimination between an image area and a non-image area can be manufactured with high reproducibility. As a further advantage, by performing the heating of the hydrophobization in the presence of the organic compound, the hydrophobization is promoted, the effect of discriminating the hydrophilicity and the hydrophobicity is further enhanced, and the quality of the printing plate can be improved. is there. Further, the printing plate material may be a material having a thermal response characteristic, and does not necessarily require a photocatalytic ability, so that the range of material selection is widened.

[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 porous anodic oxide film forming treatment was performed in a 20% by weight aqueous sulfuric acid solution (containing 0.8% by weight of aluminum) at 35 ° C. using a direct current. That is, electrolysis was performed at a current density of 13 A / dm ² , and the anodic oxide film weight was adjusted to 2.7 g / m ² by adjusting the electrolysis time. After washing this support with water,
It was immersed in a 3% by weight aqueous solution of sodium silicate at 70 ° C. for 30 seconds, washed with water and dried. The aluminum support obtained as described above had a reflection density measured by a Macbeth RD920 reflection densitometer of 0.30 and a center line average roughness of 0.58 μm.

Next, the aluminum support was vacuum-deposited.
Put in the device, total pressure 1.5x10 ^-FourTo become Torr
Heating titanium metal pieces under the condition of oxygen gas with a partial pressure of 70%
Heat and deposit on an aluminum support to remove titanium oxide
A film was formed. The crystal component of this thin film is determined by X-ray analysis.
And the ratio of amorphous / anatase / rutile crystal structure is 1.5 /
6.5 / 2, TiO_Two900 Å thin film
It was ROHM. This is wound around the substrate of the plate cylinder 1 and
An original plate for printing was used.

Using the heating unit of the embodiment shown in FIG. 3 (however, the evaporation chamber was not filled with an organic compound), heating was performed by electric heating with the heating temperature controlled at 200 ° C. The plate cylinder was rotated at a rotation speed at which the passage time of the heating unit was 2 minutes. Cont is the contact angle of water on the original plate surface after heating.
When the contact angle of the surface with water was measured by act Angle Meter CA-D (manufactured by Kyowa Interface Science Co., Ltd.) by the aerial water drop method, each part was between 48 and 55 degrees.

Next, a 150 μm × 100 μm sialon wear-resistant protective layer was provided on the Ta—SiO ₂ heating resistor of the high-temperature thermal recording section 5.
Using a heating element array in which thermal heads of 150 μm were arranged at intervals of 250 μm, they were brought into contact with the surface layer of titanium oxide to perform heating printing. The used thermal head is 2ms
The temperature reaches 220 ° C. by ec current supply and reaches 490 ° C. by 5 msec current supply. However, when the surface of the anodic oxide film having low thermal conductivity is continuously energized while scanning at 2.5 m / sec, the surface becomes almost 480 °. It was confirmed that the temperature was maintained at C by separately performing temperature measurement. The recording speed is 2.5m /
sec. At this time, from the experimental example shown in FIG. 1, the contact angle can be considered to be 10 degrees or less in the high-temperature hydrophilicity development region. Angle Meter
When the contact angle of the surface with water was measured by the aerial water droplet method using CA-D (manufactured by Kyowa Interface Science Co., Ltd.), it was between 7 and 9 degrees in the region where the thermal head scanned uniformly.

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 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 soaking a 1/1 mixed solution of a printing ink washing liquid Daiclean R (released by Dainippon Ink and Chemicals) and toluene into a waste cloth. To remove the ink. The heating was performed again at 200 ° C. in the heating unit 2. The contact angle was measured in the same way as before. Every part of the plate surface was between 48 and 55 degrees.

Next, the surface of the plate cylinder 1 was imagewise heated by a thermal head under the same conditions as described above. The plate cylinder 1 is used in a single-sided printing press of Oliver 52 manufactured by Sakurai Co., and the dampening water is supplied to the ink / fountain water supply unit 3 using pure water and the ink using Newchampion F gloss 85 black manufactured by Dainippon Ink and Chemicals, Inc. And 1000 sheets of offset printing were performed. 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-described repetition was performed five times, changes in the contact angle value after heating and recording by the thermal head, the recovery speed of the contact angle by heating at the hydrophobic development temperature, and the sharpness of the image on the printed surface were recognized. I couldn't. From these results, using a printing original plate provided with a titanium oxide layer on an aluminum support, using the printing apparatus of Embodiment 1, heating to a hydrophobic development temperature and imagewise heating with a thermal head were performed to produce a negative type plate making. It was shown that printing was possible, and that the original printing plate could be repeatedly reused only by washing and removing the ink.

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 this zinc oxide film
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.

The heating temperature was set to 200 in the same manner as in Example 1.
Heating was performed by electrothermal heating controlled at ℃. The plate cylinder was rotated at a rotation speed at which the passage time of the heating unit was 1 minute. Contact Angle Mete
r The contact angle of the surface with water was measured by the air drop method using CA-D (manufactured by Kyowa Interface Science Co., Ltd.).

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 were arranged at intervals of 250 μm, the prints were heated by bringing them into contact with the zinc oxide surface layer. The thermal head used was the same as that used in Example 1, and the scanning speed was 2.5 m / sec.
I went in. At this scanning speed, another measurement shows that the surface temperature in contact with the zinc oxide surface layer is 450 ° C. Cont determines the contact angle of the original plate surface with water after irradiation.
Using the act Angle Meter CA-D, the contact angle of water on the surface was measured by the air drop method.
It was between 0 and 13 degrees.

The plate cylinder 1 was used for a single-sided printing machine of Oliver 52 manufactured by Sakurai Co., Ltd., and the dampening water was supplied to the ink / fountain solution supply unit 3 by using pure water and the ink was 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 the heating unit 2 was energized again and heated 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 50 and 57 degrees.

Next, thermal recording was performed on the surface of the original plate through the developed film under the same conditions using the same thermal recording apparatus with a thermal head as in Example 1. The contact angle of water on the surface of the original plate after the thermal recording was measured by a water drop method in the air using Contact Angle Meter CA-D.

The plate cylinder 1 was used in a single-sided printing machine of Oliver 52 manufactured by Sakurai Co., Ltd., and the dampening water was supplied to the ink / fountain solution supply unit 3 by using pure water and the ink was 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.

From the above results, it is possible to perform printing by heating the entire surface at a temperature at which hydrophobicity is exhibited 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. Moreover, it was shown that the printing original plate can be repeatedly reproduced and used only by washing and removing the ink.

[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 the hydrophobic region to water after heating is 1
The first and second times were 45 to 50 degrees, and the contact angle of the heat mode recording area was 10 to 14 degrees. The quality of the printed surface was also free from background contamination in the first and second runs, and the discrimination between the image area and the non-image area was sufficient.

Example 4 The 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)
Is 5 × 10^-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
5 × 10^-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.

Except that this aluminum support with a barium titanate thin film was wound around the base of a plate cylinder and used as an original plate, and that an infrared laser light recording device was used in place of the thermal recording head in the thermal recording section, 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. In this case, the irradiated infrared light is S
As i absorbs, this thin layer serves to convert light energy to heat energy. That is, since the Si layer generates heat by irradiating infrared rays, the barium titanate layer can be heated. In addition, it is known from a measurement performed separately that the temperature of the barium titanate layer on the Si layer when performing infrared laser drawing under the above conditions is 360 ° C. The contact angle of water to the hydrophilic region by ultraviolet irradiation is 14 to 20 degrees in both the first and second times, and the quality of the printed surface is free from background contamination in both the first and second times. The discrimination of the regions was also sufficient.

Example 5 A polyimide (pyromellitic anhydride / m-phenylenediamine copolymer) film (trade name; Kapton, manufactured by Du Pont-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 above-mentioned polyimide film 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 become as the gas pressure (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. Then A
The gas pressure of r 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, the gas pressure as Ar / O ₂ is 60/40 (molar ratio) was set to 5 × 10 ^-3 Torr, and setting the gas pressure to 5 × 10 ^-3 Torr, RF to titanium metal target At a power of 200 W, a titanium dioxide thin film was formed by vapor deposition. The crystal component of this thin film was determined by X-ray analysis to have an amorphous / anatase / rutile crystal structure ratio of 1.5 /
6.5 / 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 high-temperature heating was 11 to 17 for the first and second times.
In addition, the quality of the printing surface was not stained in the first and second times, and the discrimination between the image area and the non-image area was sufficient.

Example 6 The following test was performed using the same apparatus as the heating section shown in FIG. A glass tube with an inner diameter of about 30 mm (a diversion filter was diverted) was disposed sideways at the air intake, and the air in the heating unit was passed through this glass tube and taken into the heating unit. The diatomaceous earth impregnated with silicone oil [trade name: Silicone KF99 (manufactured by Shin-Etsu Chemical Co., Ltd.)] was poured into the lower half of the glass tube so that the volume ratio became 50%. The temperature rises from room temperature to 150 ° C. while passing through the tube.
Since F99 has a vapor pressure of at least 1 mmHg at this temperature, the air introduced into the heating 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 this organopolysiloxane compound is introduced into the heating section and heating for hydrophobization is carried out under an atmosphere, the same plate and the same apparatus as in Example 1 are used, and the plate is made under the same conditions and printed. The used printing plate was reproduced in the same manner and printing was performed again. The maximum contact angle of water in the hydrophobic region after heating is 1
Appearing at 90 ° C., the contact angle value was 70 degrees. On the other hand, the contact angle with water of the hydrophilic region subjected to the imagewise irradiation of the active light was 9 to 11 degrees, and was not affected by silicone vapor. When this result is compared with the result obtained in Example 1, the temperature at which the contact angle becomes maximum moves to the higher temperature side by performing the heating at the hydrophobic development temperature in the presence of the organosilicon compound vapor, but at the same time, It can be seen that the contact angle was significantly increased and the lipophilicity-hydrophilicity distinctiveness was improved.

Then, 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.

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 described above, detailed description will be omitted.
In the second embodiment, each printing unit 11Y, 1
The colors of the inks supplied in the 1M, 11C and 11B ink / fountain solution supply units are Y (yellow),
M (magenta), C (cyan), and B (black) are different.

Next, the operation of the second embodiment will be described. First, the printing units 11Y, 11M, 11C,
In 11B, while the plate cylinder 1 is slowly rotated, the surface of the original sheet passing through the heating unit 2 at the hydrophobicity developing temperature is made hydrophobic. The structure of the heating unit has been described with reference to FIG.
When the temperature of the heating atmosphere and the organic compound are present, the temperature of the evaporation chamber is controlled by the control unit (34 in FIG. 3). Optimal conditions are selected according to the type. After rotating at a passing speed for a sufficient heating time to make the entire surface of the plate cylinder hydrophobic, drawing representing each color is performed by imagewise heating by the high-temperature heating recording unit 5 in FIG. The printing units 11Y, 11M, 11C, 11B
Ink of each color of Y, M, C, and B is supplied from the dampening solution supply unit, and each printing unit 11Y, 11M, 11C,
The ink and fountain solution are held in the plate cylinder 1B of 11B. Thereafter, the paper is supplied as shown by the arrow B in FIG. 5, and the ink of each of the printing units 11Y, 11M, 11C and 11B is transferred to the 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, the color image is printed on the paper in the negative type.

After the printing is completed, each of the printing units 11Y, 11Y
The ink remaining on the plate cylinder is removed by the ink cleaning units M, 11C and 11B. Thereafter, heating is performed by the heating unit 2 while slowly rotating the plate cylinder 1 to make the entire surface of the plate cylinder 1 hydrophobic, and the plate cylinder 1 returns to a state before drawing. However,
This hydrophobizing step is preferably performed immediately before the next printing to avoid the influence of the history.

[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 thermo-responsive material such as titanium oxide or zinc oxide, and a condition-controlled heating. By plate cylinder 1
A heating unit 2 for making the surface of the plate hydrophobic, a high-temperature heating recording unit 5 for performing imagewise heating of the plate cylinder 1 that has been rendered hydrophobic at a high-temperature hydrophilicity developing temperature, and a plate on which imagewise heating has been performed. An ink / fountain solution supply unit 3 for supplying ink and fountain solution to the cylinder 1;
An ink washing unit 4 for removing ink remaining on the plate cylinder 1 after printing is completed, and a blanket 6 which comes into contact with an impression cylinder 7 as an intermediate for transferring the ink held on the plate cylinder 1 to paper.
Are provided.

The print 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 entire surface of the plate cylinder is rendered hydrophobic by heating the temperature of the plate cylinder in a heating unit, and then an image representing each color is rendered in a negative mode by imagewise heating hydrophilicity by a high-temperature heating recording unit. And each printing station 14
Y, M, C, and B color inks are supplied from the Y, M, C, and B ink / fountain solution supply units, and the ink is applied to the plate cylinders 1 of the printing stations 14Y, 14M, 14C, and 14B. Hold. Thereafter, as shown by an arrow C in FIG. 5, the paper is supplied, the paper is conveyed around the impression cylinder 7, and each printing station 14Y, 14M, 14C, 1
Transfer 4B ink 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. . As a result, a color image is printed on the sheet.

After the printing is completed, 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 under the same conditions as described above, whereby the plate cylinder returns to a state before drawing by heating.

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 the 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 is performed using a printing original plate on a sheet. 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 high-temperature heating recording unit 5 are arranged clockwise from the heating unit 2. It is not limited to this, and can be arranged in any order.

Further, each of the above embodiments and examples is as follows.
The present invention is not limited to the heat-responsive materials described in these examples, and any of the heat-responsive materials described above can be used.

[0144]

The heat-responsive substance of the present invention, in particular, a printing plate having the heat-responsive metal and metal oxide as an image forming layer is heated at a temperature for exhibiting hydrophobicity to make the surface hydrophobic, and the surface is rendered hydrophobic. The printing method of forming a printing plate by forming an imagewise distribution of hydrophilicity and hydrophobicity by imagewise heating at a high hydrophilicity temperature does not require processing such as development, and directly creates a printing plate. After the printing is completed, the printing plate is deinked and the printing plate is regenerated and reused. 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. This method and apparatus are a negative type plate making method, and a plate making / printing method of directly irradiating the original plate with an image of actinic light, or an image of actinic light after heating without adjusting the hydrophobic expression area. Higher discrimination between image areas and non-image areas,
Printing quality can be improved. In addition, there is no need for active light irradiation equipment, and there is also an advantage that the image forming material does not need to have a photocatalytic ability, so that the selection range is wide.

[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 configuration of one embodiment of a heating unit provided with an organic compound vapor supply unit.

FIG. 4 is a diagram illustrating a configuration of one embodiment of a high-temperature heating 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 heating unit to hydrophobicity manifestation temperature 3 ink / fountain solution supply unit 4 ink washing unit 5 high temperature heating recording unit 6 blanket 7 impression cylinder 8 12,15 body 11Y, 11M, 11C, 11B printing unit 14Y, 14M, 14C, 14B Printing station 21 Infrared laser light source 22 Infrared laser light source drive unit 20 Editing / layout W / S 24 Air intake 25 Switching cock 26 Evaporation chamber 27 Organic compound 29 Organic compound supply means 30 Electric heater 31 Electric heater 32 Temperature Sensor 33 Temperature sensor 34 Temperature controller

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Takashi Nakamura 798 Miyadai, Kaisei-cho, Ashigaruga-gun, Kanagawa Prefecture Inside Fujisha Shin Film Co., Ltd. F term (reference) 2C034 AA12 2H084 AA13 AE05 BB02 BB16 CC05 2H096 AA06 BA13 BA20 EA04 EA23 EA27 2H114 AA04 AA14 AA22 AA24 BA06 DA04 DA08 DA73 EA03 EA05 GA03 GA09 GA33 GA38

Claims (15)

[Claims] An image of a hydrophilic region and a hydrophobic region is obtained by heating a printing plate at a temperature at which hydrophobicity is developed to make the surface hydrophobic, and then heating the surface imagewise at a temperature at which high-temperature hydrophilicity is developed. Offset printing method in which a uniform distribution is formed and a hydrophobic area is brought into contact with a printing ink to form a printing surface in which the area has received the ink, and printing is performed. 2. The offset printing method according to claim 1, wherein the hydrophobicity development temperature is 50 to 250 ° C. 3. The method according to claim 1, wherein after the ink remaining on the printing plate surface used for printing is removed by washing, the printing plate is used as a printing plate and the operation according to claim 1 or 2 is repeated to perform printing. The printing method according to claim 1, wherein the printing method is performed. 4. The offset printing method according to claim 1, wherein the printing original plate is heated in the presence of an organic compound when the printing plate is heated at a hydrophobic development temperature. 5. The method according to claim 1, wherein the organic compound present at the time of heating at the hydrophobic development temperature is at least 1 m at a temperature of 400 ° C.
The offset printing method according to claim 4, wherein the organic compound has a vapor pressure of mHg or more and is stable at a temperature at which hydrophobicity is exhibited. 6. The offset printing method according to claim 4, wherein the organic compound to be present when heated at the hydrophobic development temperature has a boiling point in the range of 30 to 400 ° C. 7. At least one of heating performed at a hydrophobic development temperature and imagewise heating performed at a high hydrophilic development temperature is performed by a heating means selected from a thermosensitive recording head and a photothermal conversion type radiation. The offset printing method according to any one of claims 1 to 6, wherein 8. The surface of the printing original plate may be any of the third to the third tables of the periodic table.
6. A material which belongs to 6 periods and is constituted by at least one of 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 7. 9. The surface of a printing original 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 FeO_x(X = 1 to 1.
5) Fewer metal oxides selected from iron oxides
Claims characterized by being constituted by both
Item 9. The offset printing method according to any one of Items 1 to 8. 10. The printing plate has a surface made of aluminum,
The offset printing method according to any one of claims 1 to 9, wherein the offset printing method is configured of at least one of a metal selected from iron, copper, germanium, nickel, zinc, tin, and silicon or an alloy thereof. . 11. An offset printing apparatus used in the method according to any one of claims 1 to 10, wherein the printing cylinder is provided with a printing plate, and the plate is heated to a hydrophobic expression temperature. Heating means for rendering the surface hydrophobic; drawing means for applying imagewise heating to the original plate at a high temperature at which hydrophilicity is exhibited to form an imagewise distribution of hydrophilic regions and hydrophobic regions; An ink supply unit for supplying a printing ink to form a printing surface in which the region has received the ink, and a printing unit for performing printing by bringing the printing surface into contact with the surface to be printed. Offset printing device. 12. The offset printing apparatus according to claim 11, further comprising means for removing ink remaining on the printing plate after printing is completed. 13. A heating means for heating at least at a hydrophobic development temperature, a drawing means for imagewise heating at a high hydrophilicity developing temperature, an ink supply means and an ink removing means are provided around the plate cylinder. 12. The method of claim 11, wherein
Or the offset printing apparatus according to 12. 14. A printing original plate constitutes a part of a plate cylinder, a heating unit for heating at least at a hydrophobic development temperature, a drawing unit for imagewise heating at a high hydrophilic expression temperature, an ink supply unit, and The offset printing apparatus according to any one of claims 11 to 13, wherein an ink removing unit is provided around the plate cylinder. 15. A heating means for heating a printing original plate at a temperature at which hydrophobicity is developed to make the surface hydrophobic, and an organic compound vapor supply means for disposing an organic compound vapor on the surface of the original plate. The offset printing apparatus according to any one of claims 11 to 14, wherein: