JP3482170B2 - Printing plate material, recycling method thereof and printing apparatus - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a printing plate material and a method for recycling the same.

[0002]

2. Description of the Related Art As a general printing technique, digitization of a printing process has been progressing recently. This is an attempt to convert image data read by a scanner or the like into digital data through a personal computer or the like, and to use the digital data as it is for producing a plate material used for printing. This makes it possible to save labor in the entire printing process and to perform high-definition printing.

By the way, as a conventional plate, a so-called P
The S version is generally known. This has anodized aluminum as a hydrophilic non-image area, and has a hydrophobic image area formed by curing a photosensitive resin on the surface thereof. Printing is performed by transferring the ink adhering to the hydrophobic image area onto the paper surface. However, this PS plate is not compatible with the digitization of the printing process described above.

On the other hand, in addition to the above-mentioned PS plate, a method for facilitating plate production in response to digitization of the printing process has been proposed. For example, a laser absorbing layer of carbon black or the like, which is coated on a PET film, and a silicon resin layer coated thereon, is used to write an image with a laser beam to heat the laser absorbing layer, and the heat causes the silicon resin layer to heat. A method is known in which a plate is burnt out to produce a plate. There is also known a method in which a lipophilic laser absorbing layer is applied on an aluminum plate, and the hydrophilic layer applied thereon is burned off with a laser beam in the same manner as described above to form a plate.

[0005]

However, the above-mentioned prior art has the following problems. First, P
Since the S plate requires a lot of time and cost for its production, it has been a factor of increasing the printing cost particularly when printing a small number of copies. In addition, when one pattern is printed and the next is printed, the plate needs to be replaced, and the plate that has been used up to now has been discarded. Furthermore, the PS plate, as described above, is not compatible with the digitization of the printing process. That is,
With the PS plate, it was not possible to directly prepare the plate from digital data, and it was impossible to realize labor-saving and digitization of the printing process for realizing high-definition printing.

[0006] Further, in the case of making a plate corresponding to the above digitization, that is, using a PET film or using an aluminum plate, it is certainly possible to make a plate directly from digital data, but regarding one pattern After printing, you cannot print unless you replace it with a new version. In other words, there is no difference from the PS plate in that the used plate is discarded. That is, the cost associated with printing is correspondingly increased. Also,
From the standpoint of protecting the global environment, which has recently been advocated, it is not a preferable situation to dispose of used plates once.

Recently, a reproducible printing plate material using a photocatalyst has been disclosed (JP-A-10-250027 and JP-A-1).
1-245533, JP-A-11-249287, etc.). However, in these publications, the sensitivity of the photocatalyst to ultraviolet rays is not specified, and further, the time required for image writing is not specified, or even if it is described, it takes 1 hour (Japanese Patent Laid-Open No.
-249287 gazette) is required, and it cannot be said that it is far from a practical level. Also, regarding the regenerating method, heat treatment (130 to 200 ° C x 1 to 5 hours, JP-A-11-245533
(Japanese Patent Laid-Open No. 11-24) and a new photo-reactive layer are formed in layers (Japanese Patent Laid-Open No. 11-24
However, it is difficult to say that the reproducing method is at a practical level because it takes too much time and the reproducing time is not specified.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a printing plate material that can be reused while being compatible with the digitization of the printing process, and a method for reproducing the printing plate material. To do.

[0009]

The present invention takes the following means in order to solve the above problems. That is, the printing plate material according to claim 1 contains a titanium oxide photocatalyst on the surface of the substrate , and Fe2 +, Ni2 +, Mn2 +, Cr3.
+ Or Cu2 + is used as an ion or acid.
And a coating layer containing a compound oxide with titanium as a complex oxide is formed directly or through an intermediate layer. By irradiating the surface of the coating layer, which exhibits hydrophobicity, with light, this printing plate material can convert the irradiated portion into hydrophilicity. this is,
Due to the action of the titanium oxide photocatalyst, Fe2
1 of +, Ni2 +, Mn2 +, Cr3 + and Cu2 +
By including one kind or two or more kinds of metals, the hydrophilization phenomenon is promoted, and more rapid plate making is possible. By using the hydrophilically converted portion as a non-image area where ink does not adhere and the remaining hydrophobic portion as an image area where ink adheres, the function as a printing plate material can be exhibited. It will be possible. Further, when an intermediate layer is interposed between the base material and the coat layer, it becomes possible to sufficiently maintain the adhesive strength of the coat layer.

[0010]

[0011]

[0012] In ^{addition, Fe 2+, Ni 2+, Mn} 2+,
One or more ionic state of cr ³⁺ and Cu ^2+, even in any state of the composite oxide state between the oxide state or titanium, to promote hydrophilic phenomenon of the titanium oxide photocatalyst by light irradiation, It basically has the effect of rapidly converting the light irradiation area on the plate surface into a hydrophilic non-image area.
In addition, as one form of the ionic state, Fe ²⁺ , N
Needless to say, one or more of i ²⁺ , Mn ²⁺ , Cr ³⁺ and Cu ²⁺ may be contained in the coat layer as salts.

The printing plate material according to claim 2 is a substrate surface.
Titanium oxide photocatalyst and W, Mo, Cr, Ge, P on the surface
b, and a small amount selected from the group consisting of these oxides.
At least the coating layer containing one kind, directly or intermediate layer
It is characterized by being formed through . This printing plate material is capable of converting the irradiated portion to hydrophilic by irradiating the surface of the initial state showing hydrophobicity with light having an energy higher than the band gap energy of titanium oxide. . This is due to the action of the titanium oxide photocatalyst. By using the hydrophilically converted portion as a non-image area where the hydrophobic ink does not adhere and the remaining hydrophobic area as the image area where the hydrophobic ink adheres, the function as a printing plate is exhibited. It becomes possible.

In the step of forming a latent image on the plate material surface by irradiating with light having an energy higher than the band gap energy of titanium oxide (hereinafter referred to as an image writing step), the surface of the coating layer containing titanium oxide photocatalyst Alternatively, W, Mo, Cr, Ge, Pb,
And less than selected from the group consisting of these oxides
Both By containing one, energy required for the conversion of the hydrophobic surface to a hydrophilic surface (hereinafter, referred to as plate material sensitivity) can be reduced.

[0015]

The printing plate as claimed in claim 3, claim 1
A printing plate according to any one of 1-2, wherein the coating layer surface is in the initial state at the time of platemaking, the contact angle of water represents at least 50 ° or more hydrophobic, and, on the surface By irradiating with light having a wavelength higher than the band gap energy of the titanium oxide photocatalyst, it is converted into a hydrophilic surface having a contact angle of water of 10 ° or less.

According to this, in the initial state at the time of producing the plate, the entire surface of the plate can be the image area. Further, since the surface of the coating layer irradiated with light having a wavelength higher than the bandgap energy of the titanium oxide photocatalyst is converted into a hydrophilic surface, that portion can be used as a non-image area. . Incidentally, this irradiation of light can be performed based on, for example, digital data conforming to an image to be printed. In this case, the printing plate material according to the present invention is a digital printing plate. It can be said that it has become compatible with this. In the present invention, the step of writing an image by irradiating light will be referred to as plate making below.

The printing plate material according to claim 4 is the printing plate material according to claim 3.
The printing plate material as described above, wherein the hydrophilic surface is used as a non-image area and the remaining hydrophobic surface is used as an image area. It can be said that this is a printing plate material having the same operation as that of the printing plate material according to claim 3 described above. Therefore, it can be said that this printing plate material can cope with the digitization of the printing process.

The printing plate material according to claim 5 is the printing plate material according to claim 3.
Alternatively, in the printing plate material according to claim 4, the energy required for converting the surface of the coat layer from hydrophobic to hydrophilic is 0.005 to ² joule / cm ² , and based on digital data. It is possible to draw directly on the printing plate. This printing plate material is capable of converting the irradiated portion to hydrophilic by irradiating the surface of the initial state, which is hydrophobic, with light. This is due to the action of the titanium oxide photocatalyst. By using the hydrophilically converted portion as a non-image area where the hydrophobic ink does not adhere and the remaining hydrophobic area as the image area where the hydrophobic ink adheres, the function as a printing plate is exhibited. It becomes possible. When writing an image directly based on digital data, the plate material sensitivity is 0.0 in order to make the writing device a practical level device in terms of cost and size of the device.
05-2 joule / cm ² is suitable.

The printing plate material according to claim 6 is the printing plate material according to claim 1.
The printing plate material according to any one of to 5 , wherein the surface of the coating layer, at least a part of which has hydrophilicity in the surface, is irradiated with an energy flux,
It is reconverted into a hydrophobic surface having a contact angle of water of at least 50 °. According to this, the surface of the coating layer including the hydrophilic portion is converted to hydrophobic by being irradiated with energy flux,
It can be considered that the printing plate material is in the initial state. This also means that the printing plate material can be reused.

The printing plate of claim 7, wherein the claim 1
A printing plate according to any one of 1 to 5, at least the coating layer surface partially exhibits hydrophilicity in its plane, by performing chemical conversion treatment, the surface is the contact angle of water It is reconverted to have a hydrophobic surface of at least 50 ° or more. By subjecting this printing plate material to a chemical conversion treatment as a substitute for the energy bundle, it is possible to obtain the same effect as the printing plate material according to claim 8 .

The printing plate material according to claim 8 is the printing plate material according to claim 1.
A printing plate according to any one of 1 to 5, at least part of the coating layer surface with a very hydrophilic in its plane, by performing in combination the irradiation and chemical treatment of energy flux, the The surface is reconverted into a hydrophobic surface having a contact angle of water of at least 50 ° or more.
This printing plate material can obtain the same effect as the printing plate material according to claim 6 by performing the energy flux and the chemical conversion treatment in combination. In this case, since it has been shown that a plurality of means are used to convert the hydrophilic surface into the hydrophobic surface, it is generally considered that the conversion can be completed promptly.

The printing plate material according to claim 9 is the printing plate material according to claim 1.
~ A printing plate according to any one of 5, by at least partially polished clean the coating layer surface exhibits hydrophilicity, reproduces the coat layer containing the titanium oxide photocatalyst in the plane thereof The surface is reconverted into a hydrophobic surface having a contact angle of water of at least 50 °.

This is achieved, for example, by forming a new coat layer again on the hydrophilic surface. As a result, an initial state in which the entire surface of the plate material is hydrophobic, that is, the entire surface is a non-image area, appears. Therefore, also by this, it is possible to exhibit the same effect as that derived from the eighth aspect . That is, this printing plate material can be reused. In the present invention, a step of generally uniformly hydrophobizing the entire surface of the coating layer containing the titanium oxide photocatalyst, in which at least a part of the surface shows hydrophilicity and the rest shows hydrophobicity, is generally used. This is called reproduction.

The printing plate material according to claim 10 is the printing plate material according to any one of claims 1 and 2 , wherein an energy higher than a band gap energy of the titanium oxide photocatalyst is provided on the coating layer. Is provided with a coating layer made of a compound that can be decomposed by irradiation with light having a wavelength of. The surface of this printing plate material can be divided into a hydrophobic portion and a hydrophilic portion by the action of the compound and the titanium oxide photocatalyst.
The hydrophilic portion is exposed by irradiating the surface of the coat layer with light (generally, ultraviolet ray). And, the non-image area where ink does not adhere to the hydrophilically converted portion,
By utilizing the remaining hydrophobic portion as the image area to which the ink adheres, it becomes possible to exert the function as a printing plate material. Further, when an intermediate layer is interposed between the base material and the coat layer, it becomes possible to sufficiently maintain the adhesive strength of the coat layer.

[0026] The printing plate material according to claim 11, wherein, the claim
11. The printing plate material according to 10 , wherein the surface of the coating layer has a contact angle of water of at least 5 in the initial state during plate preparation.
Hydrophobicity of 0 ° or more and hydrophilicity such that the surface of the coating layer is exposed and the contact angle of water on the surface of the coating layer is 10 ° or less by irradiating the surface of the coating layer with the light. It is converted to the surface.

According to this, it can be said that in the initial state at the time of making the plate, the entire surface of the plate can be the image area.
Further, since the surface of the coating layer irradiated with light having a wavelength higher than the bandgap energy of the titanium oxide photocatalyst is converted into a hydrophilic surface, that portion can be used as a non-image area. . By the way, it has been suggested that the following effects can be obtained in this hydrophilic treatment. That is, the titanium oxide photocatalyst promotes the decomposition of the compound due to its original “catalytic” action, and the titanium oxide photocatalyst surface itself becomes a hydrophilic surface with a water contact angle of 10 ° or less. It is an action. Therefore, in this case, it is supposed that the hydrophilic treatment can be completed promptly. Further, this ultraviolet irradiation can be performed based on, for example, digital data conforming to an image to be printed, and in this case, the printing plate material according to the present invention is a digitalized printing process. It can be said that it corresponds to.

The printing plate material according to claim 12 is
11. The printing plate material according to 11 , wherein the hydrophilic surface is used as a non-image area and the remaining hydrophobic surface is used as an image area. It can be said that this is a printing plate material having the same action as the printing plate material according to claim 11 described above. Therefore, it can be said that this printing plate material can make the most of the original function of the titanium oxide photo "catalyst" in the hydrophilic treatment, and can also be adapted to the digitization of the printing process.

The printing plate material according to claim 13 is the printing plate material according to any one of claims 1 to 5 , wherein at least a part of the printing plate material is hydrophilic on its surface. , By reacting or strongly interacting with a compound having an organic hydrophobic group in the molecule,
It is reconverted into a hydrophobic surface having a contact angle of water of at least 50 °. According to this, the surface of the coating layer including the hydrophilic portion is converted to hydrophobic, and it can be considered that the printing plate material is in the initial state. This also means that
This means that the printing plate material can be reused.

The printing plate material according to claim 14 is
14. The printing plate material according to 13 , wherein the compound having an organic hydrophobic group in the molecule decomposes by irradiation with light having an energy higher than the band gap energy of the titanium oxide photocatalyst by the titanium oxide photocatalysis. It is what As a result, the compound having an organic hydrophobic group in the molecule is decomposed and removed by the titanium oxide photocatalytic action under irradiation with light having energy higher than the band gap energy of the titanium oxide photocatalyst, and the coating layer containing the titanium oxide photocatalyst. Since the surface is exposed, it is possible to form a hydrophilic surface by image writing.

The printing plate material according to claim 15 is
The printing plate material according to claim 13 or 14 , wherein the compound having an organic hydrophobic group in the molecule is a fatty acid dextrin. By using the aliphatic dextrin, the hydrophilic portion on the surface of the plate material can be made sufficiently hydrophobic with a small amount of compound. Further, the water resistance to dampening water is sufficient, and the image area function can be maintained during printing.

The printing plate material according to claim 16 is
The printing plate material according to claim 13 or 14 , wherein the compound having an organic hydrophobic group in the molecule is an organic titanium compound. The printing plate material according to claim 17 ,
The printing plate material according to claim 13 or 14 , wherein the compound having an organic hydrophobic group in the molecule is an organic silane compound. In both the printing plate material according to claim 16 and the printing plate material according to claim 17 , since a compound having an organic hydrophobic group in the molecule chemically reacts with the surface of the titanium oxide catalyst, a hydrophobic oil or fat is used. Printing durability is extremely higher than that of.

The printing plate material according to claim 18 is the printing plate material according to claim 1.
6. The printing plate material as described in any one of 1 to 5 , wherein by irradiating light having an energy higher than the band gap energy of the titanium oxide photocatalyst, a hydrophobic portion which is not irradiated with light and a hydrophilic portion which is irradiated with light. A plate-making step of forming a latent image consisting of a portion converted to the surface, and after removing the ink from the plate material surface after printing, then at least in the hydrophilic portion of the plate material surface, an organic hydrophobic group in the molecule. The compound is characterized in that it can be used repeatedly by repeating the step of recycling the printing plate material by reacting or strongly interacting the compound having it.

The printing plate material according to claim 19 is the printing plate material according to claim 1.
19. The printing plate material for printing according to any one of claims 1 to 18 , which has a light source containing light having an energy higher than the band gap energy of the titanium oxide photocatalyst and which directly draws on the plate material based on digital data. With this, it is possible to write an image.

A method for recycling a printing plate material according to a twentieth aspect is the printing plate material according to any one of the first to fifth aspects,
A method for recycling a printing plate material comprising at least a step of cleaning the surface of a coating layer containing a titanium oxide photocatalyst after printing and a step of recycling the coating layer containing a titanium oxide photocatalyst.

A method for recycling a printing plate material according to claim 21 is the printing plate material according to any one of claims 1 to 5 , wherein:
After printing, a printing plate material comprising at least a step of cleaning the surface of the coating layer containing the titanium oxide photocatalyst and a step of regenerating the coating layer containing the titanium oxide photocatalyst by irradiating an energy flux thereafter. Is the method of reproduction.

A method for recycling a printing plate material according to a twenty-second aspect is the printing plate material according to any one of the first to fifth aspects,
After printing, a step of cleaning the coat layer surface containing the titanium oxide photocatalyst, and a step of regenerating the coat layer containing the titanium oxide photocatalyst by performing a chemical conversion treatment after that, at least the printing plate material for printing characterized by It is a reproduction method.

A method for recycling a printing plate material according to claim 23 is the printing plate material according to any one of claims 1 to 5 , wherein:
After completion of printing, at least including a step of cleaning the surface of the coating layer containing the titanium oxide photocatalyst and a step of regenerating the coating layer containing the titanium oxide photocatalyst by performing combined irradiation of energy flux and chemical conversion treatment thereafter. It is a characteristic method for recycling printing plate materials.

A method for recycling a printing plate material according to a twenty-fourth aspect is the printing plate material according to any one of the first to fifth aspects,
After printing, a step of cleaning the surface of the coating layer containing the titanium oxide photocatalyst, and a step of regenerating the coating layer containing the titanium oxide photocatalyst by reacting or strongly interacting with a compound having an organic hydrophobic group in the molecule thereafter. A method for recycling a printing plate material, which comprises at least the above.

It is apparent that the regenerating method described in any one of claims 20 to 24 has the same effect as that obtained from the printing plate material according to claim 9 .

A method for recycling the printing plate material according to claim 25 is the method for recycling the printing plate material according to any one of claims 20 to 24 , wherein the step of cleaning the surface of the coating layer and the coating The step of regenerating the layer is carried out on the printing press. According to this, it becomes possible to carry out continuous printing work without stopping the printing press and without interposing printing plate replacement work.

A method for recycling a printing plate material according to a twenty-sixth aspect is the printing plate material according to any one of the tenth to twelfth aspects, wherein at least a part of the surface of the printing plate material is hydrophilic after printing is completed. And at least a step of cleaning the outermost surface including the surface of the coating layer, and then re-forming the coating layer to expose a hydrophobic surface having a water contact angle of 50 ° or more. Is a method of recycling a printing plate material.

According to this, by coating the compound, the surface of the coating layer is converted into hydrophobic, and at this time, it can be considered that the printing plate material is in the initial state. Further, this means that the printing plate material can be reused. Furthermore, since the above fact, that is, the work of converting into hydrophobic, is substantially only the work of applying the compound, the work can be completed promptly.

A method for recycling a printing plate material according to a twenty-seventh aspect is a method for recycling a printing plate material according to the twenty-sixth aspect ,
The step of cleaning the outermost surface and the step of reforming the coating layer are performed on a printing machine. According to this, when actually printing, it is possible to carry out continuous printing work without interposing the interruption of the printing work that is generally considered to be involved in the work related to conversion to the hydrophobic property. .

A printer according to claim 28 is the printer according to claim 1.
20. A printing plate material according to any one of claims 1 to 19 , a writing device that directly draws on the printing plate material based on digital data, a cleaning device that removes ink from the plate material surface after printing, and a printing plate. And a recycling device for recycling the material. As a result, it becomes possible to perform the steps relating to plate production and plate reproduction on the same printing apparatus.

The printing apparatus according to claim 29 is the printing apparatus according to claim 2.
9. The printing device according to 8 , wherein the regenerating device is a device for regenerating a coating layer containing a titanium oxide photocatalyst by applying a compound having an organic hydrophobic group in the molecule to a printing plate material. To do. By this,
The same effects as those of the method for recycling a printing plate material according to claims 20 to 24 can be obtained.

[0047]

BEST MODE FOR CARRYING OUT THE INVENTION (First Embodiment) An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a sectional view of a printing plate material according to the present embodiment. In FIG. 1, the base material 1 is made of aluminum. Although it can be said that aluminum is used as a printing plate material in a very general form, the present invention is not limited to this.

An intermediate layer 2 is formed on the surface of the base material 1. Examples of the intermediate layer 2 include silica (SiO ₂ ),
Silicon compounds such as silicone resin and silicone rubber are used as the material. Among them, silicone alkyd, silicone urethane, silicone epoxy, silicone acryl, silicone polyester, etc. are particularly used as the silicone resin. This intermediate layer 2 is
It is formed in order to secure the adhesion between the base material 1 and the coat layer 3 which will be described later and to secure the adhesion. That is, the base material 1 and the intermediate layer 2 and the coat layer 3 and the intermediate layer 2 are surely brought into close contact with each other, and as a result, the adhesive strength between the base material 1 and the coat layer 3 is secured. ing.

A coat layer 3 containing a titanium oxide photocatalyst is formed on the intermediate layer 2. On the surface of the coat layer 3, it is possible to make a portion which is hydrophobic in the initial state at the time of plate production and which is hydrophilic by irradiation with ultraviolet rays. This property depends on the property of the titanium oxide photocatalyst. Note that this will be described later in detail. Moreover, this coating layer 3, by interaction with the titanium oxide photocatalyst, in order to accelerate hydrophilization phenomenon of the coating layer by ultraviolet ^{irradiation, F e 2+, Ni 2+,} Mn 2+, Cr 3+
And one or more of Cu ²⁺ are mixed as an ion, an oxide, or a complex oxide with titanium.

Further, the coat layer 3 has the above-mentioned properties.
That is, the following substances may be added for the purpose of improving the conversion property from hydrophobicity to hydrophilicity, or for the purpose of improving the strength of the coating layer 3 and the adhesion to the substrate 1. . Examples of this substance include silica-based compounds such as silica, silica sol, organosilane, and silicon resin, metal oxides or hydroxides of zirconium, aluminum, and the like, and fluorine-based resins. In consideration of the strong oxidizing power of the titanium oxide photocatalyst, it can be said that the composition of the coat layer 3 is preferably an inorganic compound from the viewpoint of preventing deterioration of the coat layer 3.

As the titanium oxide photocatalyst itself, there are anatase type and rutile type having different crystal structures, and both can be used in this embodiment. Further, the coat layer 3 has a thin film thickness in order to increase the resolution of the image written on the plate surface to enable high-definition printing.
Since it is also possible to form in the visual field, the particle diameter of the titanium oxide photocatalyst is preferably 0.1 μm or less.

As the titanium oxide photocatalyst to be used, those which are commercially available and can be used in the present embodiment are specifically listed, ST-01 manufactured by Ishihara Sangyo,
ST-21, its processed products ST-K01, ST-K03, water dispersion type STS-01, STS-02, STS-21, SSP-25, SSP-20, SSP-M, CSB manufactured by Sakai Chemical Industry. , CS
B-M, paint type LACTI-01, TAYCA's ATM-10
0, ATM-600, ST-157 and the like. However, it goes without saying that the present invention can be applied to other than these titanium oxide photocatalysts.

The coat layer 3 has a thickness of 0.01 to 10 μm.
It is preferably within the range. This is because if the film thickness is too small, it will be difficult to make full use of the above-mentioned properties, and if the film thickness is too large, the coat layer 3 will be easily cracked, which is a cause of deterioration in printing durability. This is because Since the cracks are remarkably observed when the film thickness exceeds 50 μm, even if the above range is relaxed, it is necessary to recognize the upper limit of 50 μm, preferably 10 μm. Also, in practice, it is 0.
It can be said that a general form is a film thickness of about 1 to 3 μm.

Further, as a method of forming this coat layer 3, one of Fe ²⁺ , Ni ²⁺ , Mn ²⁺ , Cr ³⁺ and Cu ²⁺ is used.
Method of applying titanium oxide photocatalyst sol to which one or more kinds of salts are added, titanium oxide photocatalyst sol and Fe ²⁺ , N
i ²⁺ , Mn ²⁺ , a method of applying a mixture of one or more oxides of Cr ³⁺ and Cu ^2+, a titanium oxide photocatalyst sol and Fe ²⁺ , Ni ²⁺ , Mn ²⁺ , Cr ³⁺ and Cu ²⁺
A method of applying a mixture of one or more of the above alkoxides, organic titanate and Fe ²⁺ , Ni ²⁺ , Mn ²⁺ ,
Method of coating mixture of Cr ³⁺ and Cu ²⁺ with one or more alkoxides, Fe ²⁺ , Ni ²⁺ , M
A titanium oxide photocatalyst layer formed by a vapor deposition method using a pellet obtained by mixing one or more oxides of n ²⁺ , Cr ³⁺ and Cu ²⁺ and a titanium oxide photocatalyst in a predetermined mixing ratio, and a film formed by the vapor deposition method. Ion implantation of one or more of Fe ²⁺ , Ni ²⁺ , Mn ²⁺ , Cr ³⁺ and Cu ²⁺ .

At this time, for example, if a coating method is adopted, a solvent, a cross-linking agent, a surfactant or the like may be added to the coating liquid used therefor. The coating liquid may be either a room temperature drying type or a heat drying type, but the latter is more preferable. This is because it is advantageous to increase the strength of the coat layer 3 by heating so as to improve the printing durability of the plate.

The operation and effect of the printing plate material having the above structure will be described below. First, in the initial state at the time of producing the printing plate material, the surface of the coat layer 3 is
As shown in FIG. 1, the contact angle of water is adjusted so that it exhibits a hydrophobicity of at least 50 ° or more. By the way, it can be said that it is more preferable if the contact angle is 80 ° or more. In this state, as can be seen from FIG. 1, it is difficult for water to adhere to the surface of the coat layer 3, that is, the so-called water repellency is extremely high. It can be said that a state has emerged in which it is easy for ink to adhere to the surface of the coat layer 3.

Incidentally, the above-mentioned "initial state at the time of plate making"
May be regarded as the start of the actual printing process. More specifically, it can be considered that the digitalized data of a given given image has already been prepared, and that it indicates the state when writing the data on the plate material. However, the stage of preparing this digitized data may be after performing the hydrophobic treatment on the surface of the coat layer 3 described later, and the above description should not be understood exactly. That is, when the "initial state at the time of plate making" is defined as "the actual start of the printing process" as described above, it should be interpreted in a broad sense.

Next, the surface of the coat layer 3 in the above state is irradiated with ultraviolet rays as shown in FIG. This ultraviolet irradiation is performed so as to correspond to the digital data relating to the image described above. In addition,
The ultraviolet ray as used herein means a light having a wavelength higher than the band gap energy of the titanium oxide photocatalyst. More specifically, it is an ultraviolet ray containing light having a wavelength of 400 nm or less.

By this ultraviolet irradiation, the surface of the coat layer 3 becomes hydrophilic as shown in FIG. This is due to the action of the titanium oxide photocatalyst. As a result, the contact angle of water on the surface of the coat layer 3 irradiated with ultraviolet rays is 10 ° or less. This state is just the opposite of the above-mentioned state of the hydrophobic surface. That is, most of the water spreads in a film form on the surface of the coat layer 3, but the printing ink cannot adhere to this surface.

The method of exposing the hydrophilic portion based on the image is simple because the ultraviolet irradiation area may be controlled based on the digital data of the image. Is possible. That is, it can be said that, unlike the conventional PS plate in which the hydrophobic portion is formed by curing the photosensitive resin, the printing plate material in the present embodiment can easily cope with the digitization of the printing process.

By the way, it is generally said that the titanium oxide photocatalyst is hydrophilized by ultraviolet irradiation. When the titanium oxide photocatalyst is hydrophobic, oxygen O ²⁻ is bonded to titanium Ti ⁴⁺ in a bridge shape on the surface as shown in FIG. 3 (a). When this is irradiated with ultraviolet rays, as shown in FIG. 3 (b), the bridge-shaped oxygen O ²⁻ becomes an O atom and is desorbed from the surface, and two electrons adjacent to each other are ejected from the desorbed O ^2−. Two Ti ⁴⁺ are reduced to Ti ³⁺ . Water molecules in the atmosphere are adsorbed and dissociated on the oxygen deficiency portions to generate hydroxyl groups.
This hydroxyl group further adsorbs water molecules in the atmosphere and forms a hydroxyl group film on the surface of the coating layer, so that it exhibits hydrophilicity. As described above, the hydrophilization phenomenon of the titanium oxide photocatalyst under UV irradiation is started by the reduction process of Ti ⁴⁺ , and a small amount of Fe ²⁺ , N 2 is ^added to the titanium oxide photocatalyst layer.
The reduction process of Ti ⁴⁺ is promoted by mixing one or more of i ²⁺ , Mn ²⁺ , Cr ³⁺ and Cu ²⁺ . The mixing amount is 0.05 to 5% by weight, preferably 0.1 to 1% by weight. If it is too small, the effect of promoting the reduction process of Ti ⁴⁺ becomes insufficient, and if it is too large, the original function of the titanium oxide photocatalyst is impaired.

After the above processing is completed, the coat layer 3
Apply printing ink to the surface. Then, for example, a printing plate material as shown in FIG. 4 is manufactured. In this figure, the hatched portion is the portion that has not been subjected to the above-mentioned hydrophilic treatment, that is, the hydrophobic portion, and therefore shows the image area 4 to which the printing ink is attached,
The remaining background portion, that is, the hydrophilic portion, shows the non-image area 5 where the printing ink has been repelled and the adhesion has not been made. As the pattern is raised in this manner, the surface of the coat layer 3 has a function as a master plate.

After this, the normal printing process is executed and then terminated. In the following, two forms will be described.

First, as a first mode, in a printing plate material that has passed through a normal printing process, the surface of the coat layer 3 is irradiated with an energy flux composed of light, heat, sound waves, electron beams, etc. Surface treatment with chemical substances such as solution, gas and catalyst, that is, chemical conversion treatment is performed. This may be done at the same time or may be done separately. By performing such an operation (treatment for removing the hydroxyl group in the hydrophilic state shown in FIG. 3), the surface of the coat layer 3 is changed to that shown in FIG.
As shown by the curve A of 1, the portion that had been hydrophilic is again hydrophobic. In FIG. 5, the horizontal axis represents time,
It is a graph in which the vertical axis represents the contact angle of water, and shows how the contact angle of water with respect to a certain point on the surface of the coat layer 3 changes with the passage of time.

Normally, a hydrophilized titanium oxide photocatalyst has a property that when it is kept in a dark place, the hydrophilized part thereof gradually shifts to a hydrophobic one naturally (Fig. 5 curve B)). This transition is usually
It will be completed in about one week to one month, and then the entire surface will become hydrophobic again. Further, when utilizing the hydrophobic performance and hydrophilic performance of the titanium oxide photocatalyst, it is general to make efforts to maintain hydrophilicity. That is, it is a conventional idea and generally accepted that efforts are made to further prolong the transition from hydrophilicity to hydrophobicity, which takes about one week to one month.

By the way, in the present embodiment, as described above, Fe ²⁺ , Ni ²⁺ , Mn ²⁺ , Cr ³⁺ and Cu are used.
By mixing 1 type or 2 types or more of ²⁺ , the rate of hydrophilization at the time of ultraviolet irradiation is improved, and the surface of the coat layer 3 having hydrophilicity is positively treated by irradiation of energy flux and chemical conversion treatment. A process for restoring the hydrophobic property will be performed. Therefore, we do not try to maintain hydrophilicity, and we do not wait for the transition to hydrophobicity, which takes about one week to one month, to complete. It is something that will be tried in the meantime.

In the present embodiment, it is possible to return to the above-mentioned "initial state at the time of plate making" by promptly completing the return to the hydrophobic state.
That is, at this time, the surface of the coat layer 3 exhibits a hydrophobic property such that the printing ink can be attached to the entire surface, and by irradiating the surface with ultraviolet rays again, a new master plate for printing can be produced. It will be possible. In short, the printing plate material according to the present embodiment can be reused, in other words, can be repeatedly used.

Other modes will be described below. In this embodiment, first, the ink, dampening water, etc. adhering to the plate surface, that is, the surface of the coat layer 3 is wiped off. That is, the surface of the coat layer 3 is cleaned. After that, the coat layer 3 containing the titanium oxide photocatalyst is formed again, so that a new hydrophobic surface is created. For the reproduction of the coat layer 3, the above-mentioned sol coating method, organic titanate method, vapor deposition method or the like may be appropriately used. Practically, it is preferable to select the coating method. In this case, specifically, spray coating, blade coating, dip coating, roll coating or the like may be used. The used coat layer may be removed before the coat layer 3 is regenerated. The thickness of the regenerated coat layer 3 is preferably 0.05 μm or more, but if the thickness exceeds 20 μm, cracks are likely to occur, so care must be taken.

As a result, it is apparent that, even in this embodiment, the plate can be repeatedly used or reused as shown in FIG. 6, as in the embodiment described with reference to FIG. That is, it can be said that the printing plate material has returned to the “initial state at the time of plate making” at that time, because the coating layer 3 which becomes the hydrophobic surface has been created again. If done, it is possible to create a new parent plate.

In the following, more specific examples confirmed by the inventors of the present invention regarding the production and printing of the printing plate material will be described. First, the area is postcard size and the thickness is 0.
A 3 mm aluminum base material was prepared, to which a primer LAC PR-01 manufactured by Sakai Chemical Industry was applied and dried. The thickness of the primer layer after drying was 1.4 μm. Note that this primer layer corresponds to the intermediate layer 2 in FIG. After that, the NiO sol was added to the titanium oxide photocatalyst coating agent LAC TI-01 manufactured by Sakai Chemical Industry Co., Ltd. with Ni ^2+.
A solution containing 0.2% by weight of titanium oxide in terms of conversion was prepared, applied on a substrate and dried at 100 ° C. to form a coat layer 3 containing a titanium oxide photocatalyst having a thickness of 1.0 μm. With respect to this printing plate material, the contact angle of water on the surface of the coat layer 3 was measured with a CA-W type contact angle meter of Kyowa Interface Chemistry. .

Next, the above printing plate material was subjected to SAN PRINTING MAC.
Attached to a HINRS SAN OFF-SET 220E DX type card printing machine, using Toyo Ink ink HYECOO B Ben MZ and Mitsubishi Heavy Industries dampening solution litho-fellow 1% solution, printing speed of 2500 sheets on Ivest paper. Printing was done at / hour. As a result, the ink adhered to the entire surface of the plate material (that is, the surface of the coating layer 3 and the same hereinafter), and a red image having the same size and uniform density as the plate could be printed on the paper surface.

In addition, in the printing plate material which has been coated up to the coating layer 3, that is, in the printing plate material in the initial state at the time of plate preparation, the illuminance of 40
Immediately after irradiating with ultraviolet rays of mW / cm ² for 1 minute, the above-mentioned CA-
When the contact angle of water was measured with a W-type contact angle meter, it was 4
And showed sufficient hydrophilicity as a non-image area. When printing was performed using this plate material in the same manner as described above, ink did not adhere to the plate surface and an image could not be printed on the paper surface. In addition, in the printing plate material prepared without adding NiO sol, the contact angle of water was 1 due to ultraviolet irradiation.
It took 5 minutes to reach 0 ° or less.

Further, as in the previous case, in the printing plate material in the initial state at the time of making the plate, the substantially central portion of the surface of the plate material was masked with a square black paper having a side of 2 cm, and the unmasked portion was illuminated. After irradiating with ultraviolet light of 40 mW / cm ² for 1 minute, the contact angle of water was measured immediately with a CA-W type contact angle meter on the ultraviolet irradiation area, and the contact angle was 5 °, indicating that the non-image area was sufficiently hydrophilic. Showed sex. When printing was performed in the same manner as above using this plate material, ink did not adhere to the plate surface where the ultraviolet rays were irradiated, and a square red image with a side of 2 cm corresponding to the masked plate material was printed on the paper surface. Was able to print.

Next, there will be explained the following two examples concerning the reproduction of the printing plate material. First, the printing plate material wiped off the ink and dampening water adhering to the plate surface was sealed in a dark room so as not to be exposed to weak ultraviolet rays. The dark room was kept under a nitrogen gas atmosphere. Also, 5 for the plate surface
A heat treatment at 180 ° C. was performed for a minute. As a result, in the printing plate material that had been subjected to these treatments, when the contact angle of water on the surface of the plate material was measured using a CA-W type contact angle meter, it was 93 °, which was a hydrophobic value before UV irradiation. Back to the sexual surface.

Next, with the plate attached to the card printing machine, the ink adhering to the plate surface and the dampening water were wiped off,
After applying the titanium oxide photocatalytic coating agent LAC TI-01 on the plate surface by roll coating, 12
The coat layer 3 containing the titanium oxide photocatalyst was regenerated by drying with hot air at 0 ° C. When printing was performed using this recycled plate in the same way as printing before the recycling process, ink adhered to the entire surface of the plate material, and a red image of the same size and uniform density as the plate was printed on the paper surface. did it.

The above printing was performed by using a printing machine 10 as shown in FIG. That is, this printing machine 10
The (printing device) has a plate cylinder 11 as a center, and a coating device 12 (reproducing device) and a blanket cylinder 1 around the plate cylinder 11.
3, a plate cleaning device 14 (cleaning device), a writing device 15, an inking roller 16, and a drying device 17. The printing plate is the plate cylinder 1.
It is wound around 1 and installed.

In the printing machine 10, the step of regenerating the plate for which printing has been completed as described above is performed as follows.
First, the plate cleaning device 14 is brought into contact with the plate cylinder 11, and the ink and dampening water adhering to the plate surface are wiped off. After that, the plate cleaning device 14 is removed from the plate cylinder 11, and the coating device 12 is brought into contact with the plate cylinder 11. As a result, the coat layer 3 is regenerated on the plate material. After that, the coating device 12 is attached to the plate cylinder 11.
And the drying device 17 is operated to dry the solvent and the like contained in the coat layer 3. Next, based on the digital data of the image prepared in advance, the image is written on the surface of the coat layer 3 reproduced by the ultraviolet rays emitted from the writing device 15. After the above steps are completed, the inking roller 16 and the blanket cylinder 13 are brought into contact with the plate cylinder 11. Then, the paper 18 contacts the blanket cylinder 13 and flows in the direction of the arrow shown in FIG. 7, whereby continuous printing is performed.

As described above, the printing plate material in the present embodiment utilizes the property of the titanium oxide photocatalyst, that is, the property of conversion from hydrophobic to hydrophilic,
It can be reused and the amount of plate material discarded after use can be significantly reduced. Therefore,
It is possible to significantly reduce the cost related to the plate material. In addition, since it is possible to directly write the image from the digital data related to the image to the plate material by using light (ultraviolet rays), the printing process has been digitized, which is a considerable amount. It is possible to shorten the time and reduce the cost. Further, Fe ²⁺ , Ni ²⁺ , Mn ²⁺ ,
By mixing one or more of Cr ³⁺ and Cu ^{2+ in} the form of ions, oxides, or composite oxides with titanium, the hydrophilization rate under UV irradiation can be improved, It is possible to shorten the time for writing the image to the.

Further, since it is possible to perform the reconversion of the printing plate material and the reproduction of the coat layer 3 on the printing machine, it is possible to speed up the printing operation. In the above example, since the image writing on the surface of the coat layer 3 was also performed on the printing machine, a quicker work can be performed.

Although the intermediate layer 2 is provided between the base material 1 and the coat layer 3 in the present embodiment,
The present invention is not limited to this. That is, the intermediate layer 2 does not necessarily have to be provided. It should be noted that this can be said even if the intermediate layer 2 is not provided,
As is clear from the above description, the main essence of the present invention is not impaired.

Further, regarding the reproduction of the plate, the embodiment or the example in which the coat layer 3 is newly applied has been described above. That is, even if a method of removing the surface layer portion of the coat layer 3 that has been used up to that point is used instead of newly coating the coat layer 3 after printing is completed, the same effect as described above can be obtained. It is a point. That is, if one surface of the coat layer 3 shown in FIG. 2 and the like is shaved after printing, the hydrophilic part is removed at once, and instead a new surface of the coat layer 3 that is reserved on the back side is exposed. Can be made. Since the surface of the new coat layer 3 exhibits hydrophobicity, it can be understood that the initial state at the time of plate production can be finally revealed even by such a method. The "regeneration of the coat layer" as referred to in the present invention includes the concept just described within the range.

(Second Embodiment) A second embodiment according to the present invention will be described below. FIG. 7 shows a sectional view of the printing plate material according to the present embodiment. In FIG.
The base material 21, the intermediate layer 22 and the coat layer 23 are the above-mentioned first
Since it is the same as the embodiment described above, detailed description will be omitted.

On the coat layer 23, a coating layer 24 made of a compound that can be decomposed by irradiation with light having a wavelength higher than the band gap energy of the titanium oxide photocatalyst is formed. As shown in FIG. 7, the surface of the coating layer 24 is hydrophobic such that the contact angle of water is at least 50 °. By the way, it can be said that it is more preferable if the contact angle is 80 ° or more.
In this state, as can be seen from FIG. 7, it is difficult for water to adhere to the surface of the coating layer 24, that is, the so-called water repellency is extremely high. It can be said that the state in which the ink easily adheres to the surface of the coating layer 24 has appeared.

The operation and effect of the printing plate material having the above structure will be described below. First, in the initial state during the production of the printing plate material, the surface of the coat layer 23 is adjusted so that the contact angle of water is at least 50 ° or more as shown in FIG. The "initial state at the time of plate production" and "adjusting so as to show hydrophobicity" here refer to the following circumstances. First, “to adjust so as to exhibit hydrophobicity” means that the surface of the coating layer 23 is a coating layer 24 made of a compound decomposable by ultraviolet irradiation.
By forming and drying it. For this application, a method such as spray coating, blade coating, dip coating, or roll coating may be appropriately adopted. Also, the drying is
The method may be either normal temperature or heating. Then, when the surface of the coat layer 23 becomes hydrophobic due to these "adjustments", it is defined as "the initial state at the time of plate production".

As the above-mentioned compound, it is preferable that the compound has a function of imparting hydrophobicity to the surface and, at the same time, a compound which is “easily” subjected to oxidative decomposition reaction by irradiation with ultraviolet rays. Specifically, (1) trimethylmethoxysilane, trimethylethoxysilane, dimethyldiethoxysilane, methyltrimethoxysilane, tetramethoxysilane, methyltriethoxysilane, tetraethoxysilane, methyldimethoxysilane, octadecyltrimethoxysilane, octadecyltrisilane Alkoxysilanes such as ethoxysilane; (2) trimethylchlorosilane, dimethyldichlorosilane, methyltrichlorosilane, methyldichlorosilane,
Chlorosilanes such as dimethylchlorosilane; (3) Vinyltrichlorosilane, vinyltriethoxysilane, γ-chloropropyltrimethoxysilane, γ-chloropropylmethyldichlorosilane, γ-chloropropylmethyldimethoxysilane, γ-chloropropylmethyldiethoxysilane A silane coupling agent such as γ-aminopropyltriethoxysilane; (4) silazane such as hexamethyldisilazane, N, N′-bis (trimethylsilyl) urea, N-trimethylsilylacetamide, dimethyltrimethylsilylamine, diethyltrimethylsilylamine; (5) Fluoroalkylsilanes such as perfluoroalkyltrimethoxysilane; (6) Silicone oil of dimethylhydrogenpolysiloxane type; (7) Lauric acid, myristic acid, palmitic acid, steari Acids, fatty acids such as oleic acid; (8) alkoxytitanium such as tetraisopropoxytitanium, tetra-n-butoxytitanium, tetrastearoxytitanium; (9) tri-n-butoxytitanium stearate, isopropoxytitanium tristearate. Titanium acylates such as; (10) Titanium chelates such as diisopropoxytitanium bisacetylacetonate and dihydroxy bislactotitanium; (11) Fatty acid dextrins; However, it goes without saying that the present invention is not limited to only these compounds. further,
Needless to say, these compounds may be diluted with a solvent before use.

The above-mentioned "initial state at the time of plate making"
More generally, it may be regarded as the start of the actual printing process. In other words, it can be considered that the digitalized data of a given image has already been prepared and is intended to be written on the plate material. However, the stage of preparing the digitized data may be after performing the hydrophilic treatment on the surface of the coat layer 23 described later, and the above description should not be understood exactly. That is, when the "initial state at the time of plate making" is defined as "the actual start of the printing process" as described above, it should be interpreted in a broad sense.

Next, the surface of the coating layer 24 in the above state is irradiated with ultraviolet rays as shown in FIG. This ultraviolet irradiation is performed so as to correspond to the digital data relating to the image described above. In addition,
The ultraviolet ray as used herein means a light having a wavelength higher than the band gap energy of the titanium oxide photocatalyst. More specifically, it is an ultraviolet ray containing light having a wavelength of 400 nm or less.

As shown in FIG. 8 by the irradiation of ultraviolet rays, the compound constituting the coating layer 24 is decomposed so that the surface of the coating layer 3 appears and the surface becomes hydrophilic. To be converted. This is due to the action of the titanium oxide photocatalyst. Since the decomposition of the compound proceeds due to the original action of the titanium oxide photo "catalyst", it is completed extremely quickly. As a result, the contact angle of water on the surface of the surface of the coat layer 3 irradiated with ultraviolet rays is 10 ° or less. This state has an opposite relationship to the state of the hydrophobic surface of the coating layer 24. That is,
Most of the water spreads like a film on the surface of the coat layer 23, but the printing ink cannot adhere to this surface.

The titanium oxide photocatalyst was exposed to ultraviolet light.
With regard to the mechanism for making hydrophilic, the first embodiment has already been
The explanation is omitted here because it is explained in the present invention.
In addition, a small amount of F was added to the coating layer containing the titanium oxide photocatalyst.
e²⁺, Ni²⁺, Mn²⁺, Cr ³⁺And Cu²⁺One kind of
Is a titanium oxide photocatalyst by containing two or more
We are trying to promote the hydrophilization of.

After the above processing is completed, the coating layer 24
Alternatively, printing ink is applied to the surface of the coat layer 23 that has been subjected to the hydrophilic treatment. Then, for example, a printing plate material as shown in FIG. 9 is manufactured. In this figure, the hatched portion is the portion that has not been subjected to the above-mentioned hydrophilic treatment, that is, the hydrophobic portion or the portion where the coating layer 24 remains, and therefore shows the image portion where the printing ink is attached, The printing ink is repelled on one of the white background portions, that is, the hydrophilic portion or the surface portion of the coat layer 23,
The non-image area where the adhesion has not been made is shown. Since the pattern is raised in this manner, the printing plate material has a function as a master plate.

After that, the normal printing process is executed and the process is terminated. Then, the coating layer 24 made of the compound as described above is formed again on the printing plate material after the printing. Therefore, the printing plate material has returned to the "initial state at the time of plate production" again at the stage of finishing the coating. That is, at this time, on the surface of the coat layer 23, the coating layer 24 on which the printing ink can be attached
Thus, a new master plate for printing can be prepared by irradiating the surface again with ultraviolet rays. In short, the printing plate material according to the present embodiment can be reused, in other words, can be repeatedly used.

The graph shown in FIG. 10 collectively shows the above description. This is time on the horizontal axis,
FIG. 6 is a graph in which the vertical axis represents the contact angle of water, showing how the contact angle of water on the surface (that is, hydrophobic or hydrophilic state) of the printing plate material in the present embodiment changes with time. It is shown. In this figure, the titanium oxide photocatalyst alone does not have sufficient performance related to hydrophobicity (contact angle of water before UV irradiation does not exceed 50 °).
However, it shows the case where a titanium oxide photocatalyst having the ability to rapidly complete the conversion from hydrophobic to hydrophilic is used.

According to this, first, the original coat layer 23
On the surface, as mentioned above, the contact angle of water is 20
It is ~ 30 ° and the hydrophobic performance is not sufficient. Therefore, as it is, it is not sufficient to use it as an image area, and it cannot be used as a printing plate material. However,
As shown in the figure, this titanium oxide photocatalyst has the ability to be rapidly converted into a hydrophilic surface upon irradiation with ultraviolet rays. Normally, this conversion generally takes about 10 minutes, but in this example, it can be seen that the conversion is completed within 1 to 2 minutes.

Next, by applying a compound to the surface of the coat layer 23, that is, by forming the coating layer 24, the hydrophobicity of the plate material is brought to a sufficient state as shown by a point B via the curve A in FIG. Become. In other words, the ink can be attached and can be used for printing. Also,
This is the "initial state during plate making" (point B in Fig. 10)
Is. Incidentally, in order to reveal this "initial state at the time of plate making", it is clear that it is possible to complete this in an extremely short time because it is only necessary to apply the compound substantially as described above.

After that, ultraviolet irradiation is performed to decompose the compound and at least part of the surface of the coat layer 23 is converted into a hydrophilic part. In this case, the titanium oxide photocatalyst as described above, which has a large conversion rate from hydrophobic to hydrophilic, is used, and the decomposition of the compound is, as described above, the nature of the titanium oxide photocatalyst. Completed quickly, and further Fe ²⁺ , N
i ²⁺ , Mn ²⁺ , Cr ³⁺ and Cu ²⁺ are mixed in one kind or in two or more kinds to improve the hydrophilization rate at the time of ultraviolet irradiation, and three effects of this titanium oxide photocatalyst The conversion from hydrophobic to hydrophilic can be completed in 1 min as shown by the curve C in FIG.

The printing ink is attached to the printing plate material which has been subjected to the above-mentioned treatment, and the actual printing is carried out as indicated by a straight line D in FIG. Thereafter, when printing is completed, the printing plate material is subjected to treatments such as application of a compound and irradiation with ultraviolet rays in the same manner as described above, and is reused.

As described above, the printing plate material according to the present embodiment has an advantage that the cycle can be speeded up, in addition to the advantage that it can be reused. That is, according to the above, regardless of whether hydrophobicity is imparted or hydrophilicity is imparted, the work for realizing them is not time-consuming. Therefore, the entire printing process can be completed very quickly.

In the following, more specific examples confirmed by the inventors of the present invention concerning the production and printing of the printing plate material will be described. First, the formation of the coat layer 23 is performed in the same manner as in the first embodiment, and octadecyltrimethoxysilane (trade name, manufactured by Toshiba Silicone Co., Ltd. is formed on the surface of the coat layer 23.
TSL8185) is diluted with ethanol to a concentration of 3 wt% and slowly stirred for 5 minutes.
m was added and slowly stirred again for 5 minutes to prepare a hydrophobic treatment liquid, which was applied by roll coating. Then, this was dried at 100 ° C. to form a coating layer, and the “initial state at the time of plate production” explained several times was revealed.

The plate material dried and coated with the above-mentioned hydrophobizing treatment solution (that is, an ethanol solution of octadecyltrimethoxysilane and formic acid) was masked with a square paper having a side of 2 cm on the substantially central portion of the surface of the plate material. After irradiating the unmasked area with UV light with an illuminance of 40 mW / cm ² for “1 minute”, the masked area and the UV irradiated area were immediately contacted with Kyowa Interface Chemistry CA-W type contact angle meter. When the contact angle was measured, the contact angles were “82 °” and “0” for the masking part and the ultraviolet irradiation part, respectively.
.About.2.degree. ", And the masking portion showed sufficient hydrophobicity as an imaged portion, and the ultraviolet irradiation portion exhibited sufficient hydrophilicity as a non-imaged portion.

This plate material is made by SAN PRINTING MACHINRS S
AN OFF-SET 220E DX-type card printing machine, using Toyo Ink ink HYECOO B Ben MZ and Mitsubishi Heavy Industries dampening water litho-fellow 1% solution to print on Ivest paper at a printing speed of 2500 sheets / hour I went. As a result, ink did not adhere to the plate surface of the portion irradiated with ultraviolet rays, and a red image of a square having a side of 2 cm corresponding to the masked plate material portion could be printed on the paper surface.

Further, subsequently, the printing plate material after printing is thoroughly wiped off with ink and dampening water, and then a hydrophobic treatment liquid is applied by the same method as described above. Is dried, and the diameter is 2 cm at the center of the plate surface.
A prototype was manufactured by irradiating with ultraviolet light having an illuminance of 40 mW / cm ² for 1 minute by masking the circular black mask. That is, this is a process performed when the printing plate material is reused. Also by this, the contact angle of water in the ultraviolet irradiation portion is 0 to
It became 2 °, showing sufficient hydrophilicity as a non-image area, and in actual printing, a circular red image having a diameter of 2 cm corresponding to the masked plate material portion could be printed on the paper surface.

Next, with the plate attached to the card printing machine, the ink and dampening water adhering to the plate surface are wiped off, and the hydrophobic treatment liquid is applied by roll coating.
The plate material surface was made hydrophobic by drying with hot air at 120 ° C.
The approximately central portion of the hydrophobized plate was masked with a regular triangular black paper having a side of 2 cm, and the unmasked portion was irradiated with ultraviolet rays having an illuminance of 40 mW / cm ² for 1 minute. When this plate material was printed in the same manner as described above, ink did not adhere to the plate surface of the portion irradiated with ultraviolet rays, and a red image of a regular triangle with a side of 2 cm corresponding to the masked plate material portion was obtained. I was able to print on the paper.

The above printing was performed using the printing machine 10 shown in FIG. 11 described in the first embodiment. That is, the printing machine 10 is provided with a plate cylinder 11, a coating device 12, a blanket cylinder 13, a plate cleaning device 14, a writing device 15, an inking roller 16 and a drying device 17 around the plate cylinder 11. ing. The printing plate material is wound around the plate cylinder 11 and installed.

In this printing machine 10, the actual process of reusing the plate for which printing has been completed as described above is carried out as follows. First, the plate cleaning device 14 is brought into contact with the plate cylinder 11, and the ink and dampening water adhering to the outermost surface of the plate material, that is, the plate surface are wiped off. After that, the plate cleaning device 14 is detached from the plate cylinder 11,
The coating device 12 is in contact with the plate cylinder 11.
As a result, the hydrophobic treatment liquid is applied onto the plate material. After that, the coating device 12 is detached from the plate cylinder 11 and the drying device 17 is operated to dry the hydrophobizing treatment liquid. Next, based on the digital data of the image prepared in advance, the image is written on the surface of the plate material that has been made hydrophobic by the ultraviolet rays emitted from the writing device 15. After the above steps are completed, the inking roller 16 and the blanket cylinder 13 are brought into contact with the plate cylinder 11. And
11 so that the paper 18 contacts the blanket cylinder 13 and
Continuous printing is performed by flowing in the direction of the arrow indicated by.

As described above, the printing plate material in the present embodiment utilizes the property of the titanium oxide photocatalyst, that is, the property of conversion from hydrophobic to hydrophilic,
It can be reused and the amount of plate material discarded after use can be significantly reduced. Therefore,
It is possible to significantly reduce the cost related to the plate material. In addition, since it is possible to directly write the image from the digital data related to the image to the plate material by using light (ultraviolet rays), the printing process has been digitized, which is a considerable amount. It is possible to shorten the time and reduce the cost.

Moreover, as mentioned above,
A book that forms a coating layer 24 to reuse the printing plate material
In the case of the embodiment, it is possible to accelerate the entire printing process.
Will be done. This means that the decomposition of the compound
Promoted by the original action of titanium oxide light "catalyst"
The fact that it is completed promptly contributes greatly. In addition,
In the first place, titanium oxide has a high conversion rate from hydrophobic to hydrophilic
Fe using a photocatalyst ²⁺, Ni²⁺, Mn²⁺, Cr³⁺And
And Cu²⁺One or more of ions, oxides,
Is even more if it is included in the state of a complex oxide with titanium
It will greatly contribute to speeding up.

Further, since the process for reusing the printing plate material can be performed on the printing machine, the printing operation can be speeded up. In addition,
In the above example, since the image writing on the surface of the coating layer 24 was also performed on the printing machine, it is possible to carry out a quicker work.

Although the intermediate layer 22 is provided between the base material 21 and the coat layer 23 in the present embodiment, the present invention is not limited to this. That is, the intermediate layer 23 does not necessarily have to be provided. Note that this can be said because even if the intermediate layer 23 is not provided, the main essence of the present invention is not impaired, as is clear from the above description.

(Third Embodiment) A third embodiment will be described below with reference to the drawings. In the third embodiment, the same components as those in the other embodiments described above are designated by the same reference numerals, and detailed description thereof will be omitted.

The layer structure of the printing plate material of the third embodiment is the same as the layer structure of the printing plate material shown in FIG. 1 in the first embodiment. An intermediate layer 2 is formed on the surface of the base material 1.

A coat layer 3 containing a titanium oxide photocatalyst is formed on the intermediate layer 2. Unlike the first embodiment, in order to improve the sensitivity of the titanium oxide photocatalyst to light, the surface of the titanium oxide photocatalyst or the photocatalyst phase is replaced with Fe ²⁺ , Ni ²⁺ , Mn ²⁺ , Cr ³⁺ and Cu ²⁺ . In addition, W, Mo, Cr, Ge, Pb,
And at least selected from the group consisting of these oxides
One kind is contained.

In the case of directly writing an image based on digital data, in order to make the writing device a practical level device in terms of cost and size of the device, the plate material sensitivity is 0.005 to 2 joule / Although it is preferable that the thickness is cm ² , it is not easy to achieve this plate material sensitivity with the titanium oxide photocatalyst alone. Therefore, the present inventors have considered adding a substance having a sensitizing effect in order to increase the sensitivity of the plate material from 0.005 to ² joule / cm ^2, and to add W, Mo, Cr, Ge, and It was found that Pb is effective for expressing the sensitizing effect.

The surface of the coating layer 3 exhibits hydrophobicity in the initial state during plate making, and exhibits hydrophilicity when irradiated with light having a wavelength higher than the bandgap energy of the titanium oxide photocatalyst, for example, ultraviolet rays. It is possible to have parts appear. This property depends on the property of the titanium oxide photocatalyst. The other components of the coat layer 3 are the same as those in the first embodiment.

[0114]W, Mo, Cr, Ge, Pb, and
At least one selected from the group consisting of these oxides
Is contained on the titanium oxide photocatalyst surface or in the photocatalyst phase.
However, it is contained on the titanium photocatalyst surface.
Is preferred. For example, the content of titanium oxide on the photocatalyst surface
If you want toW, Mo, Cr, Ge, Pb, and this
At least one selected from the group consisting of these oxidesIncluding
Solution is applied to the surface of the titanium oxide photocatalyst and then heated.
It can be included by reason.

As the solution containing W, Mo and Cr , for example, a liquid obtained by dissolving tungstic acid (H ₂ WO ₄ ), molybdic acid (H ₂ MoO ₄ ), and chromic acid (H ₂ CrO ₄ ) in an aqueous ammonia solution is used. mentioned, Ge, as the solution containing Pb, for example, acetic acid germanium (Ge (CH
₃ COO) ₄ ) in acetone, lead nitrate (Pb (N
Examples thereof include a solution in which O ₃ ) ₂ ) is dissolved in an ammonium aqueous solution, but are not limited thereto.

These W, Mo, Cr, Ge, Pb, and
The addition amount of these oxides is 0.5 to 50% or less, preferably 1% by weight with respect to the titanium oxide photocatalyst.
~ 30% is good. If it is less than 1%, the effect of addition is difficult to be expressed,
When it is 50% or more, the original photocatalytic action of titanium oxide is lowered. The reason why the photocatalytic activity of titanium oxide is enhanced by integrating these metals or metal oxides with the titanium oxide photocatalyst is not clear, but these metals or metal oxides have the action of enhancing the charge separation efficiency of the photocatalyst. It is estimated to be.

The printing plate material of the third embodiment is the first
The same effect as that of the printing plate material of the embodiment is obtained. Also,
The printing process using the printing plate material of the third embodiment and its effects are the same as those of the first embodiment, but the plate recycling process is different as follows. That is, first, after wiping off the ink, dampening water, paper dust, etc. attached to the surface of the coating layer 3 after printing, the compound having an organic hydrophobic group in the molecule is reacted with at least the hydrophilic portion of the plate surface. Alternatively, it is possible to strongly interact with each other to make the hydrophilic portion hydrophobic so that the surface of the plate material can be regenerated to the initial hydrophobic state.

The compound used for the above-mentioned hydrophobizing treatment not only has a function of reacting or strongly interacting with at least the hydrophilic portion of the plate material surface to impart hydrophobicity to the hydrophilic surface, but also under the irradiation of ultraviolet rays. In the above, those which are easily decomposed by the action of the titanium oxide photocatalyst are preferable. Further, in order to improve the plate material sensitivity, the titanium oxide photocatalyst contains W, Mo, Cr, Ge, Pb, and
Due to the addition of at least one selected from the group consisting of these oxides, the function of decomposing the organic substance of the titanium oxide photocatalyst is lower than that of the case where the titanium oxide photocatalyst is 100%. Therefore, a compound that can sufficiently hydrophobize the hydrophilic portion on the surface of the plate material with a small amount of compound and that is easily decomposed and removed by the action of the titanium oxide photocatalyst is particularly preferable.

Further, since dampening water is continuously supplied to the surface of the plate material together with the ink during printing, the water resistance to dampening water must be sufficient to maintain the function of the image area. Fatty acid dextrin is suitable as a compound satisfying such conditions.

Specifically, a solution prepared by dissolving a fatty acid dextrin in an organic solvent such as toluene is applied to the surface of the plate material in a required amount and then heated at 50 to 120 ° C. to make the surface of the plate material hydrophobic. . The fatty acid dextrin solution may be applied to the plate surface by a method such as spray coating, blade coating, dip coating or roll coating. By rewriting the non-image area on the plate surface which has returned to the hydrophobic state with ultraviolet rays in this manner, the plate can be repeatedly used.

The concentration of the fatty acid dextrin in the organic solvent solution may be 0.05% by weight or more from the viewpoint of hydrophobicity. In order to decompose titanium by photocatalysis, the concentration of fatty acid dextrin may be 5% by weight or less, more preferably 1% by weight or less. In this way, a small amount of fatty acid dextrin can be used for sufficient hydrophobicization, and as a result,
A major feature of the hydrophobizing treatment of the present invention is that the fatty acid dextrin can be easily decomposed and hydrophilicized in a short time at the time of writing an image after reproduction.

The graph shown in FIG. 12 collectively shows the above description. This is a graph in which the horizontal axis represents time (or operation) and the vertical axis represents the contact angle of water, and the contact angle of the surface (that is, hydrophobic or hydrophilic state) of the printing plate material according to the present embodiment. Shows how changes with time or operation.

According to this, first, the surface of the coat layer 3 at the beginning shows a high hydrophobicity with a contact angle of water of 80 ° or more, which is the “initial state at the time of plate making” (point A in FIG. 12). is there. Thereafter, ultraviolet rays are irradiated to prepare a printing plate using at least a part of the surface of the coating layer 3 as a hydrophilic non-image area and a non-ultraviolet ray as a hydrophobic image area, and a straight line C in FIG.
Printing will be performed as shown in FIG. When printing is completed, the surface of the coat layer 3 is made hydrophobic again by cleaning the surface of the coat layer 3 for deposits, dirt, etc., and then subjecting it to a hydrophobic treatment with the fatty acid dextrin solution.
The point A ') in 2 is returned to the "initial state at the time of plate production", and this printing plate material is reused. In the present invention, at least a part of the inner surface thereof exhibits hydrophilicity, and the remaining surface of the plate material exhibits hydrophobicity.
The process of returning to the "initial state at the time of plate production" by making the entire surface uniformly hydrophobic is referred to as plate reproduction.

As described above, the printing plate material of the present embodiment has an advantage that the cycle can be speeded up, in addition to the advantage that it can be reused. That is, combining a titanium oxide photocatalyst with high UV sensitivity with a technology that can sufficiently hydrophobize the plate material surface with a small amount of treatment and hydrophobize the titanium oxide surface with a fatty acid dextrin that is easily decomposed by the action of the titanium oxide photocatalyst. In either case, it does not take a long time to carry out the process for realizing the properties, whether it is imparting the hydrophobic property or the hydrophilic property. Therefore, the entire printing process can be completed very quickly.

According to the present invention, a series of plate reproduction steps including cleaning of the plate surface after printing, plate reproduction by hydrophobic treatment, and writing of non-image areas by ultraviolet rays are carried out while the plate is attached to the printing machine. It can be done on the press. Further, it is possible to directly draw on the plate material by turning on / off the light based on the digital data. The irradiation light amount necessary for this drawing is, for example, plate material sensitivity 0.005 to ² joule / cm ²
In order to write an image on the A zero size plate (864 × 1212 mm) in 30 seconds, the irradiation light amount is 1.7 to 700 W.

Since the printing plate can be produced by irradiating the surface of the plate material in the initial state with the light of the above-mentioned amount of light and writing the non-image area, it can be said that the printing process can be digitized. In the present invention, the process of writing an image with light will be hereinafter referred to as plate making.

The printing apparatus of the present invention comprises a plate cylinder on which the plate material according to the present invention is mounted, a writing device for directly drawing on the plate material according to digital data, and a cleaning device for removing ink from the surface of the plate material after printing. And at least a reproducing apparatus for reproducing the plate by making the plate material hydrophobic, and performing steps related to plate production and plate reproduction on a printing machine. According to this, it is possible to carry out continuous printing work without stopping the printing apparatus and without interposing printing plate replacement work. It goes without saying that the plate cylinder in the printing apparatus of the present invention may be a plate cylinder having a coat layer similar to the surface of the plate material of the present invention on the surface. Further, as the reproducing apparatus for making the plate material hydrophobic, an apparatus adopting a method of applying the fatty acid dextrin solution to the surface of the plate material is preferable, but the application method is not limited to the method illustrated in FIG. After completion of the hydrophobizing treatment, the plate making process used for the next printing may be started.

Hereinafter, more specific examples confirmed by the inventors of the present application relating to the production and printing of the printing plate material will be described. First, a base material made of aluminum having an area of postcard size and a thickness of 0.3 mm was prepared, and the primer LAC PR-01 manufactured by Sakai Chemical Industry was applied and dried. The thickness of the dried primer was 0.8 μm. The primer layer corresponds to the intermediate layer 2 in FIG. Then, a titanium oxide photocatalyst coating agent LAC TI-01 manufactured by Sakai Chemical Industry was applied and dried at 100 ° C. to form a coating layer containing a titanium oxide photocatalyst having a thickness of 0.4 μm. Next, a solution of tungstic acid dissolved in ammonia water (tungstic acid concentration: 0.5% by weight) was roll-coated, followed by heat treatment at 400 ° C. for 40 minutes to form a coating layer 3. Tungsten W and titanium Ti on the surface of the plate material after film formation
The ratio of W / Ti was about 0.1. With respect to this printing plate material, the contact angle of water on the surface of the coat layer 3 was measured using a CA-W contact angle meter manufactured by Kyowa Interface Science, and as a result, it was 88 °, showing sufficient hydrophobicity as an image area. It was confirmed that it was in the initial state at the time of plate making.

Next, the printing plate material in the initial state at the time of plate making is masked with a square black paper having a side of 2 cm on the substantially central portion thereof, and the unmasked portion has an illuminance of 12 mW / c.
After irradiating the ultraviolet ray of m ² for 20 seconds, the contact angle of water was measured immediately with a CA-W type contact angle meter for the ultraviolet ray irradiated portion, and the contact angle was 8 °, showing sufficient hydrophilicity as the non-image area. Indicated. This plate material was attached to the desktop offset printing machine New Ace Pro of Alpha Giken Co., Ltd. and printed on Ibest paper using Toyo Ink's ink HYECOO B Ben MZ and Mitsubishi Heavy Industries' dampening solution litho-fellow 1% solution. Printing was performed at a speed of 3500 sheets / hour. As a result, ink did not adhere to the plate surface of the portion irradiated with ultraviolet rays, and a red image of a square having a side of 2 cm corresponding to the masked plate surface portion could be printed on the paper surface.

Next, examples relating to the reproduction of the printing plate material will be described. First, fatty acid dextrin (Chiba Flour Milling Co., Ltd.)
0.2 g was dissolved in 99.8 g of toluene (manufactured by Katayama Chemical Co., Ltd.) to prepare a treatment liquid A (fatty acid dextrin concentration: 0.2% by weight). After the completion of printing, the treatment liquid A was applied to the printing plate material on which the ink, dampening water, paper dust, etc. adhering to the plate surface were wiped off cleanly, and dried at 100 ° C. for 5 minutes. Then immediately CA-
When the contact angle of water was measured at several points on the entire plate surface with a W-type contact angle meter, the contact angle was 113 °, showing sufficient hydrophobicity as an image area, and the printing plate material was in the initial state during plate making. It has been confirmed that.

Next, the printing plate material in the initial state at the time of plate making was masked with a circular black paper having a diameter of 2 cm at the substantially central portion, and the unmasked portion had an illuminance of 12 mW / cm ^2.
After irradiating the ultraviolet rays for 20 seconds, the contact angle of water was immediately measured with a CA-W type contact angle meter on the ultraviolet irradiation portion, and the contact angle was 6 °, showing sufficient hydrophilicity as a non-image area. . This plate material was attached to the desktop offset printing machine New Ace Pro of Alpha Giken Co., Ltd. and printed on Ibest paper using Toyo Ink's ink HYECOO B Ben MZ and Mitsubishi Heavy Industries' dampening solution litho-fellow 1% solution. Printing was performed at a speed of 3500 sheets / hour. As a result, ink did not adhere to the plate surface of the portion irradiated with ultraviolet rays, and a circular red image having a diameter of 2 cm corresponding to the masked plate surface portion could be printed on the paper surface. I printed 5,000 copies of this circular image.
On the 0th sheet, a clear circle equivalent to the initial one could be printed, and it was confirmed that the image area formed by the hydrophobic treatment had sufficient water resistance (printing durability).

In order to perform the above printing and plate reproduction on the printing machine, it is preferable to use a printing machine 30 (printing apparatus) as shown in FIG. That is, this printing machine 3
0 is a plate cleaning device 32 (cleaning device) and a hydrophobic treatment device 33 around the plate cylinder 31.
(Reproducing device), writing device 34, drying device 35, inking roller 36, dampening water supply device 37, and blanket cylinder 38. The printing plate is
It is installed by being wound around the plate cylinder 31.

In this printing machine 30, the step of regenerating the plate for which printing has been completed as described above is performed as follows.
First, the plate cleaning device 32 is brought into contact with the plate cylinder 31, and the ink, dampening water, paper dust, etc. adhering to the plate surface are wiped off cleanly. After that, the plate cleaning device 3
2 is detached from the plate cylinder 31, the hydrophobic treatment device 33 is brought into contact with the plate cylinder 31 to apply the fatty acid dextrin solution to the plate cylinder 31, and then the surface of the plate cylinder 31 is heated and dried by the drying device 35. As a result, the surface of the printing plate material is subjected to the hydrophobic treatment as described above, and is regenerated to the initial state at the time of making the plate. After that, the hydrophobic treatment device 33 is detached from the plate cylinder 31, and then an image is written on the surface of the regenerated coat layer 3 by the ultraviolet rays emitted from the writing device 34 based on the digital data of the image prepared in advance. . After the above steps are completed, the inking roller 36, the dampening water supply device 3
7. The blanket cylinder 38 is brought into contact with the plate cylinder. Then, the paper 39 is brought into contact with the blanket cylinder 38 and conveyed in the direction of the arrow shown in FIG. 13, whereby continuous printing is performed.

As described above, the printing plate material of the present embodiment has the energy required to convert from hydrophobic to hydrophilic when the titanium oxide photocatalyst is irradiated with a wavelength having an energy higher than the band gap energy. And a technique of regenerating the plate material after use with a compound that makes the surface of the plate material hydrophobic with a small treatment amount found by the present inventors and is rapidly decomposed by the organic substance decomposing action of the titanium oxide photocatalyst. By using these in combination, it is possible to realize a rapid regeneration step thereof, and it is possible to significantly reduce the amount of plate material discarded after use. Therefore, the costs associated with the plate material and the plate production can be significantly reduced accordingly. In addition, since it is possible to directly write the image from the digital data related to the image to the plate material by light (ultraviolet ray), the printing process is digitized, and a considerable amount of it is required. It is possible to reduce time or cost. Furthermore, since it is possible to perform the reconversion of the printing plate material and the reproduction of the coat layer 3 on the printing machine, it is possible to realize the speeding up of the printing operation. In the above example, the coat layer 3
Since the image writing on the surface is also performed on the printing machine, a quicker work can be performed.

(Fourth Embodiment) A fourth embodiment of the present invention will be described below with reference to the drawings. In addition,
In the fourth embodiment, the same components as those in the other embodiments described above are designated by the same reference numerals, and detailed description thereof will be omitted.

The printing plate material of the fourth embodiment has the same structure as the printing plate material of the first and third embodiments and has the same operation and effect, The regeneration process of is different as follows. That is, first, after wiping off the ink, dampening water, paper dust, etc. attached to the surface of the coating layer 3 after printing, the compound having an organic hydrophobic group in the molecule is reacted with at least the hydrophilic portion of the plate surface. Alternatively, it is possible to strongly interact with each other to make the hydrophilic portion hydrophobic so that the surface of the plate material can be regenerated to the initial hydrophobic state. As the above-mentioned compound, of course, it has the effect of reacting or strongly interacting with at least the hydrophilic part of the plate material to impart hydrophobicity to the hydrophilic surface, and at the same time, it easily acts by the action of the titanium oxide photocatalyst under ultraviolet irradiation. Those that are decomposed are preferred.

Specifically, organic titanium compounds and organic silane compounds are preferable. Since these compounds react with the hydroxyl groups present on the titanium oxide photocatalyst surface and are immobilized on the surface, in principle, a monolayer-like hydrophobic base layer is formed on the titanium oxide surface. The reaction scheme is shown in FIG. It is a feature of the regenerating method of the present embodiment that the surface of titanium oxide can be made hydrophobic, that is, the plate material can be regenerated by the monolayer-like hydrophobic base layer.

According to this embodiment, when a non-image area is written on the plate surface by ultraviolet rays after the plate is reproduced to form a latent image on the plate, the monolayer hydrophobic base layer is rapidly decomposed by the titanium oxide photocatalyst. -Since it is removed, it is effective in shortening the time required to write an image on the plate material and reducing the energy of light. Furthermore, since this monolayer-like hydrophobic base layer chemically reacts with the surface of titanium oxide, it has an advantage of extremely high printing durability as compared with the case where a hydrophobic oil or fat is applied. Furthermore, since the surface of titanium oxide is made hydrophobic by a monolayer hydrophobic base layer, there are advantages that the procedure for regeneration is easy and the amount of materials required for regeneration is small, that is, the regeneration cost is low.

Such organic titanium compounds and organic silane compounds are shown below. Alkoxytitanium such as tetraisopropoxytitanium, tetra-n-butoxytitanium and tetrastearoxytitanium; titanium acylate such as tri-n-butoxytitanium stearate and isopropoxytitanium tristearate; diisopropoxytitanium bisacetylacetonate;
Titanium chelate such as dihydroxy / bislactotitanium; trimethylmethoxysilane, trimethylethoxysilane, dimethyldiethoxysilane, methyltrimethoxysilane, tetramethoxysilane, methyltriethoxysilane, tetraethoxysilane, methyldimethoxysilane,
Alkoxysilanes such as octadecyltrimethoxysilane and octadecyltriethoxysilane; trimethylchlorosilane, dimethyldichlorosilane,
Chlorosilanes such as methyltrichlorosilane, methyldichlorosilane and dimethylchlorosilane; vinyltrichlorosilane, vinyltriethoxysilane, γ-chloropropyltrimethoxysilane, γ-chloropropylmethyldicorolosilane, γ-chloropropylmethyldimethoxysilane, γ- Examples include, but are not limited to, silane coupling agents such as chloropropylmethyldiethoxysilane and γ-aminopropyltriethoxysilane; fluoroalkylsilanes such as perfluoroalkyltrimethoxysilane. Further, it goes without saying that these compounds may be diluted with a solvent or the like as needed before use.

After applying the organotitanium compound or organosilane compound or a solution of the compound to the surface of the plate material by a method such as spray coating, blade coating, dip coating or roll coating,
It may be dried at room temperature or in a heated state. By rewriting the non-image area on the plate surface which has returned to the hydrophobic state with ultraviolet rays in this manner, the plate can be repeatedly used.

The graph shown in FIG. 12 collectively shows the above description. This is a graph in which the horizontal axis represents time (or operation) and the vertical axis represents the contact angle of water, and the contact angle of the surface (that is, hydrophobic or hydrophilic state) of the printing plate material according to the present embodiment. Shows how changes with time or operation.

According to this, first, the surface of the coat layer 3 at the beginning shows a high hydrophobicity with a contact angle of water of 80 ° or more, which is the "initial state at the time of plate making" (point A in FIG. 12). is there. Thereafter, ultraviolet rays are irradiated to prepare a printing plate using at least a part of the surface of the coating layer 3 as a hydrophilic non-image area and a non-ultraviolet ray as a hydrophobic image area, and a straight line C in FIG.
Printing will be performed as shown in FIG. When the printing is finished, the surface of the coat layer 3 is made hydrophobic (FIG. 12) again by cleaning the deposits, stains, etc. on the surface of the coat layer 3 and then subjecting the molecule to a hydrophobic treatment with a compound having an organic hydrophobic function. The point A ') in the middle, that is, the "initial state at the time of plate production" is returned to, and this printing plate material is reused.

As described above, the printing plate material according to the present embodiment has an advantage that the cycle can be speeded up, in addition to the advantage that it can be reused. That is, by combining a titanium oxide photocatalyst with high UV sensitivity with a technology of hydrophobizing the titanium oxide surface with a monomolecular layer of an organic hydrophobic group that is easily decomposed by the action of the titanium oxide photocatalyst, hydrophobicity can be imparted. In any case, in order to impart hydrophilicity, the work for realizing them will not take time. Therefore, the entire printing process can be completed very quickly.

According to the present invention, a series of plate reproduction steps of cleaning the plate surface after printing, plate reproduction by hydrophobizing treatment, and writing of non-image areas by ultraviolet rays are carried out while the plate is attached to the printing machine. It can be done on the press. Further, by turning on / off the light based on the digital data, it is possible to draw directly on the plate material. The irradiation light amount required for this drawing is, for example, A of plate material sensitivity 0.005 to ² joule / cm ² .
In order to write an image on a zero size plate (864 × 1212 mm) in 30 seconds, the irradiation light amount is 1.7 to 700 W.

Since the printing plate can be produced by irradiating the surface of the plate material in the initial state with the above-mentioned light amount of light and writing the non-image area, it can be said that the printing process can be digitized. The printing apparatus used in this embodiment has the same configuration as the printing apparatus used in the third embodiment, and has the same operation and effect.

In the following, more specific examples relating to the printing plate material and the printing system confirmed by the inventors of the present application will be described. First, a base material made of aluminum having an area of postcard size and a thickness of 0.3 mm was prepared, and the primer LAC PR-01 manufactured by Sakai Chemical Industry was applied and dried. The thickness of the dried primer was 0.8 μm. The primer layer corresponds to the intermediate layer 2 in FIG. Then, a titanium oxide photocatalyst coating agent LAC TI-01 manufactured by Sakai Chemical Industry was applied and dried at 100 ° C. to form a coating layer containing a titanium oxide photocatalyst having a thickness of 0.4 μm. Next, a solution of tungstic acid dissolved in ammonia water (tungstic acid concentration: 0.5% by weight) was roll-coated and then heat-treated at 400 ° C. for 40 minutes to form a coating layer 3. Tungsten W and titanium Ti on the surface of the plate material after film formation
The ratio of W / Ti was about 0.1. With respect to this printing plate material, the contact angle of water on the surface of the coat layer 3 was measured using a CA-W contact angle meter manufactured by Kyowa Interface Science.
It was 94 °, showing sufficient hydrophobicity as the image area, and it was confirmed that it was in the initial state at the time of plate making.

Next, the central portion of the printing plate material in the initial state at the time of plate making was masked with a square black paper having a side of 2 cm, and the unmasked portion had an illuminance of 40 mW / c.
After irradiating with m ² of ultraviolet rays for 20 seconds, the contact angle of water was measured immediately with a CA-W type contact angle meter for the ultraviolet irradiation portion, and the contact angle was 7 °, showing sufficient hydrophilicity as the non-image area. Indicated. This plate material was attached to the desktop offset printing machine New Ace Pro of Alpha Giken Co., Ltd. and printed on Ibest paper using Toyo Ink's ink HYECOO B Ben MZ and Mitsubishi Heavy Industries' dampening solution litho-fellow 1% solution. Printing was performed at a speed of 3500 sheets / hour. As a result, ink did not adhere to the plate surface of the portion irradiated with ultraviolet rays, and a red image of a square having a side of 2 cm corresponding to the masked plate surface portion could be printed on the paper surface.

Next, examples relating to the reproduction of the printing plate material will be described. First, tetra-n-butoxy titanium (Nippon Soda
2 g was dissolved in 98 g of Isopar L (manufactured by Exxon Chemical Co.) (treatment liquid B). After the completion of printing, the treatment liquid B was applied to the printing plate material on which the ink, dampening water, paper dust, etc. adhering to the plate surface were wiped off cleanly, and dried at 60 ° C. for 5 minutes. afterwards,
Immediately, the contact angle of water was measured at several points on the entire plate surface with a CA-W contact angle meter, and the contact angle was 102 °, showing sufficient hydrophobicity as an image area, and the printing plate material was used during plate making. It was confirmed that it was in the initial state.

Next, the central portion of the printing plate material in the initial state at the time of plate making was masked with a circular black paper having a diameter of 2 cm, and the unmasked portion had an illuminance of 40 mW / cm ^2.
After irradiating the ultraviolet ray for 20 seconds, the contact angle of water was immediately measured with a CA-W type contact angle meter on the ultraviolet ray irradiated portion, and the contact angle was 5 °, showing sufficient hydrophilicity as a non-image area. . This plate material was attached to the desktop offset printing machine New Ace Pro of Alpha Giken Co., Ltd. and printed on Ibest paper using Toyo Ink's ink HYECOO B Ben MZ and Mitsubishi Heavy Industries' dampening solution litho-fellow 1% solution. Printing was performed at a speed of 3500 sheets / hour. As a result, ink did not adhere to the plate surface of the portion irradiated with ultraviolet rays, and a circular red image having a diameter of 2 cm corresponding to the masked plate surface portion could be printed on the paper surface. I printed 5,000 copies of this circular image.
Even on the 0th sheet, a clear circle equivalent to the initial one could be printed, and it was confirmed that the image area formed by the hydrophobic treatment had sufficient printing durability. In order to perform the above printing and plate reproduction on the printing machine, the printing system 3 as shown in FIG.
It is preferable to use 0.

As described above, the printing plate material according to the present embodiment is converted from hydrophobic to hydrophilic by irradiating with a wavelength having a known property of the titanium oxide photocatalyst, that is, a wavelength having an energy higher than the band gap energy. By combining the properties of the above and the technology of converting the hydrophilicity to the hydrophobicity found by the present inventors, it is possible to reuse them and significantly reduce the amount of plate material discarded after use. it can. Therefore, the cost associated with the plate material can be significantly reduced accordingly. In addition, since it is possible to directly write the image from the digital data related to the image to the plate material by light (ultraviolet ray), the printing process is digitized, and a considerable amount of it is required. It is possible to reduce time or cost. Furthermore, since it is possible to perform the reconversion of the printing plate material and the reproduction of the coat layer 3 on the printing machine, it is possible to realize the speeding up of the printing operation. In addition,
In the above example, since the image writing on the surface of the coat layer 3 was also performed on the printing machine, it is possible to carry out a quicker work.

[0151]

As described above, in the printing plate material according to claim 1, the coating layer containing the titanium oxide photocatalyst is formed directly or through the intermediate layer on the surface of the substrate,
Light having a wavelength higher than that of the titanium oxide photocatalyst on its surface (ultraviolet light)
By irradiating with, it is possible to convert from hydrophobic to hydrophilic. Therefore, this makes it possible to exert the function as a printing plate material by utilizing the hydrophobic portion as the image area and the hydrophilic portion as the non-image area. And Fe2 +, Ni2 +,
One or more of Mn2 +, Cr3 + and Cu2 +
On top of ions, oxides, or complex oxides with titanium
And by mixing with, it is possible to improve the hydrophilization speed under ultraviolet irradiation, it is also possible to shorten the image writing time to the plate. At this time, by providing an intermediate layer between the base material and the coat layer, the adhesion strength between the two can be made sufficient.

In addition , F e ²⁺ , Ni ²⁺ , Mn ²⁺ ,
Accelerating the hydrophilization phenomenon of titanium oxide photocatalyst by light irradiation regardless of whether one or more of Cr ³⁺ and Cu ²⁺ is in an ionic state, an oxide state or a complex oxide state with titanium. However, it basically has the effect of promptly converting the light irradiation area on the plate surface into a hydrophilic non-image area.

In the printing plate material according to claim 2 , the coating layer is made of W, Mo, Cr, Ge, Pb, or an oxide thereof.
Since it contains at least one selected from the group consisting of the objects, it is possible to improve the plate material sensitivity.

In the printing plate material according to claim 3, since the surface of the coating layer exhibits hydrophobicity with a contact angle of water of at least 50 ° or more in the initial state at the time of plate production, in the initial state, It can be said that the entire surface of the printing plate can be used as an image area. Conversely, by irradiating the surface of the coat layer with ultraviolet rays so as to copy the image, the image can be made to stand out, and this can be used as a master plate. Further, by irradiating the surface of the coating layer with light having a wavelength higher than the bandgap energy of the titanium oxide photocatalyst, that portion can be used as a non-image area. It should be noted that this ultraviolet irradiation can be performed based on digital data that conforms to the image to be printed. Therefore, it can be said that the printing plate material according to the present invention is compatible with the digitization of the printing process, and therefore, the printing time can be greatly shortened and the cost can be reduced.

Further, the printing plate material according to claim 4 can also be adapted to the digitization of the printing process, and similar to the above, the printing time can be greatly shortened and the cost can be reduced. it can.

The printing plate material according to claim 5 is the printing plate material according to claim 3.
Alternatively, in the printing plate material according to claim 4, the energy required for converting the surface of the coat layer from hydrophobic to hydrophilic is 0.005 to ² joule / cm ² , and based on digital data. It is possible to draw directly on the printing plate.

The printing plate material according to claim 6 converts the surface into hydrophobic by irradiating the surface of the coating layer, at least a part of which is hydrophilic, with an energy flux. Can be reused.
Therefore, unlike the conventional printing plate material, it is not necessary to dispose of it at the end of printing, and the cost can be reduced accordingly.

The printing plate material according to claim 7 is intended to reuse the printing plate material by performing a chemical conversion treatment instead of the irradiation of the energy flux. According to this, it is apparent that the same effect as in claim 6 can be obtained.

Further, the printing plate material according to the eighth aspect is intended to reuse the printing plate material by performing the irradiation of the energy flux and the chemical conversion treatment in combination. Also by this, the same effect as that of claim 6 can be obtained. Further, in the present invention, since a plurality of means are used as described above, the conversion from hydrophilic to hydrophobic can be completed promptly.

The printing plate material according to the ninth aspect is intended to directly achieve the recycling of the printing plate material by recycling the coating layer. Although the means are different as described above, it is obvious that the same effect as the effect described in claim 6 can be obtained.

The printing plate material according to claim 10 is hydrophobic by the action of a compound and a titanium oxide photocatalyst that can be decomposed by irradiating with light having a wavelength higher than the bandgap energy of the titanium oxide photocatalyst. It is possible to divide the region into a part showing the property and a part showing the hydrophilic property.

According to the printing plate material of the eleventh and twelfth aspects, in the printing plate material of the tenth aspect , the same effects as those of the third and fourth aspects can be obtained.

In the printing plate material according to claim 13 , a compound having an organic hydrophobic group in the molecule is reacted or strongly interacted with the surface of the coating layer, at least a part of which is hydrophilic, to thereby form the surface. Since it is converted to hydrophobic, the printing plate material can be reused. Therefore, unlike the conventional printing plate material, it is not necessary to dispose of it at the end of printing, and the cost can be reduced accordingly.

The printing plate material according to claim 14 is
14. The printing plate material according to 13 , wherein the compound having an organic hydrophobic group in the molecule decomposes by irradiation with light having an energy higher than the band gap energy of the titanium oxide photocatalyst by the titanium oxide photocatalysis. Since it is decomposed and removed by the photocatalytic action of titanium oxide by irradiation with light, and the surface of the coating layer containing the photocatalyst of titanium oxide is exposed, it is possible to form a hydrophilic surface by image writing. .

The printing plate material according to claim 15 is
13. The printing plate material according to claim 13 or 14 , wherein the compound having an organic hydrophobic group in the molecule is a fatty acid dextrin, so that the hydrophilic portion of the plate surface is sufficiently hydrophobic with a small amount of the compound. Can be converted. Further, the water resistance to dampening water is sufficient, and the image area function can be maintained during printing. Further, both the printing plate material according to claim 16 and the printing plate material according to claim 17 are hydrophobic because the compound having an organic hydrophobic group in the molecule chemically reacts with the titanium oxide catalyst surface. Printing durability is extremely high compared to oils and fats.

The printing plate material according to claim 18 is the printing plate material according to claim 1.
5. The printing plate material as described in any one of 1 to 5 , which is characterized in that it can be repeatedly used by repeating the plate making step and the step of recycling the printing plate material.
The printing plate material according to claim 19 is the printing plate material according to any one of claims 1 to 1.
9. The printing plate material according to any one of 8 , wherein the writing device has a light source containing light having an energy higher than the band gap energy of the titanium oxide photocatalyst and draws directly on the plate material based on digital data. The image writing is possible.

Further, claims 20 to 24 and claim 2
It is apparent that the method for recycling a printing plate material according to the sixth aspect has the same action and effect as the action and effect derived from the ninth aspect .

Further, in the method of regenerating the printing plate material according to the twenty-fifth and twenty- seventh aspects, since the conversion of the surface of the coating layer into the hydrophobic state and the regeneration are performed on the printing machine, the method is generally involved during the work. There is no interruption of printing work that is considered to be. Therefore, continuous printing work can be performed, and the printing work can be speeded up. In addition,
It goes without saying that in the present invention, the merits of reusing the plate can be enjoyed at the same time.

The printer according to claim 28 is the printer according to claim 1.
20. A printing plate material according to any one of claims 1 to 19 , a writing device that directly draws on the printing plate material based on digital data, a cleaning device that removes ink from the plate material surface after printing, and a printing plate. Since the apparatus is provided with a reproducing apparatus for reproducing the material, it is possible to perform the steps related to plate production and plate reproduction on the same printing apparatus.

The printing apparatus according to claim 29 is the printing apparatus according to claim 28 , wherein the regenerating apparatus applies a compound having an organic hydrophobic group in the molecule to a printing plate material for oxidation. A device for regenerating a coat layer containing a titanium photocatalyst, which is characterized in that
The same effects as those of the printing plate material recycling method described in 20 to 24 are obtained.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a configuration of a printing plate material according to a first embodiment. This figure also shows a state in which the surface of the coat layer is hydrophobic.

FIG. 2 is a cross-sectional view of a printing plate material showing a state in which the surface of the coat layer exhibits hydrophilicity.

FIG. 3 is an explanatory diagram illustrating conversion from hydrophobicity to hydrophilicity in a titanium oxide photocatalyst.

FIG. 4 is a perspective view showing an example of an image (image area) drawn on the surface of the coat layer and its white background (non-image area).

FIG. 5 is a graph showing the state of conversion of the surface of the coat layer from hydrophobic to hydrophilic over time.

FIG. 6 is a graph showing the state of conversion of the surface of the coat layer from hydrophobicity to hydrophilicity, which is different from that of FIG. 5, along with time.

FIG. 7 is a cross-sectional view showing a configuration of a printing plate material according to a second embodiment. This figure also shows a state in which the surface of the coat layer is hydrophobic.

FIG. 8 is a cross-sectional view of a printing plate material showing a state in which the surface of the coat layer exhibits hydrophilicity.

FIG. 9 is a perspective view showing an example of an image (image area) drawn on the surface of the coat layer and its white background (non-image area).

FIG. 10 is a graph showing the state of conversion of the surface of the coat layer from hydrophobic to hydrophilic over time.

FIG. 11 is an explanatory diagram illustrating an example of the configuration of a printing machine.

FIG. 12 is a graph showing the state of conversion of the surface of the coat layer from hydrophobic to hydrophilic over time.

FIG. 13 is an explanatory diagram illustrating another example of the configuration of the printing machine.

FIG. 14 is a reaction scheme for explaining hydrophobicization of titanium oxide surface by a compound having an organic hydrophobic group in the molecule.

[Explanation of symbols]

1,21 Base material 2,22 Middle layer 3,23 coat layer 24 coating layer 10,30 Printing machine (printing device) 12 Coating equipment (reproduction equipment) 14,32 plate cleaning device (cleaning device) 15,34 Writing device 33 Hydrophobizing device (reproducing device)

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-11-174664 (JP, A) JP-A-11-123804 (JP, A) JP-A-10-344804 (JP, A) JP-A 2000-181068 (JP, A) JP-A-11-258860 (JP, A) JP-A-2000-3046 (JP, A) JP-A-10-35131 (JP, A) JP-A-10-250027 (JP, A) Flat 9-131914 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) B41N 1/14 B41C 1/10

Claims (29)

(57) [Claims] 1. A titanium oxide photocatalyst is included on the surface of a substrate.
And Fe2 +, Ni2 +, Mn2 +, Cr3 + and
And one or more of Cu2 + and ions, oxides,
Alternatively, a printing plate material is characterized in that a coat layer containing a composite oxide with titanium is formed directly or via an intermediate layer. 2. A titanium oxide photocatalyst on the surface of a substrate,
W, Mo, Cr, Ge, Pb and their oxides
A coat layer containing at least one selected from the group consisting of
But direct or printing plate material you characterized in that via an intermediate layer is formed. 3. The surface of the coating layer is in an initial state during plate making.
State, the contact angle of water is at least 50 ° or more
And shows a titanium oxide photocatalyst band on the surface.
Illuminates light with a wavelength that has an energy higher than the gap energy.
Hydrophilicity table with water contact angle of 10 ° or less
The printing plate material according to claim 1 , wherein the printing plate material is converted into a surface . 4. The hydrophilic surface is a non-image area, and the remaining hydrophobic surface.
4. The surface is used as an image area.
The printing plate material described. 5. The surface of the coating layer is changed from hydrophobic to hydrophilic.
The energy required when doing is 0.005 to 2 joul
e / cm2, directly on the plate based on digital data
Claim 3 or claim characterized in that drawing is possible
Item 4. The printing plate material according to item 4 . 6. At least a part of the surface is hydrophilic.
Irradiating the surface of the coating layer showing the property with an energy flux.
The contact angle of water is at least 50 °
The printing plate material according to any one of claims 1 to 5, wherein the printing plate material is reconverted to have the above hydrophobic surface . 7. At least a part of the surface is hydrophilic.
By applying a chemical conversion treatment to the surface of the above-mentioned coating layer exhibiting properties
The contact angle of water is at least 50 ° or more.
The printing plate material according to claim 3 , wherein the printing plate material is reconverted to have a hydrophobic surface . 8. At least a part of the surface is hydrophilic.
Irradiation and conversion of energy flux on the surface of the coating layer that exhibits
The surface is exposed to water by combining multiple treatments.
Re-create the surface so that the antenna has a hydrophobic surface with at least 50 °.
Printing plate according to any one of claims 1 and converting 5. 9. At least a part of the surface is hydrophilic.
The surface of the coating layer exhibiting properties is cleaned by polishing,
By regenerating the coating layer containing the titanium oxide photocatalyst
The contact angle of water is at least 50 ° or more.
6. The printing plate material according to any one of claims 1 to 5, which is reconverted to have a hydrophobic surface . 10. The titanium oxide photocatalyst on the coating layer.
Has a higher energy than the band gap energy of the medium
A coating consisting of a compound that can be decomposed by irradiating light with a wavelength
The printing plate material according to claim 1 or 2, further comprising a cloth layer . 11. The surface of the coating layer is in an initial state during plate making.
State, the contact angle of water is at least 50 ° or more
Irradiating the surface of the coating layer with the light
The surface of the coating layer is exposed and
Hydrophilic surface where the contact angle of water is less than 10 °
The printing plate material according to claim 10 , wherein the printing plate material is converted into. 12. The hydrophilic surface is a non-image area, and the remaining hydrophobic surface.
The characteristic surface is used as an image area.
11. The printing plate material according to item 11 . 13. An organic hydrophobic group is present in the molecule on the surface of the coating layer, at least a part of which is hydrophilic in the plane.
To react or strongly interact with compounds
The printing plate material according to any one of claims 1 to 5 , wherein the surface is re-converted into a hydrophobic surface having a contact angle of water of at least 50 °. 14. A compound having an organic hydrophobic group in the molecule.
From the bandgap energy of titanium oxide photocatalyst
Titanium oxide photocatalysis under irradiation of light with high energy
14. The printing plate material according to claim 13, which is decomposed by 15. A compound having an organic hydrophobic group in the molecule
Things, claim 13 or claim 14 printing plate according to, characterized in that a fatty acid dextrin. 16. A compound having an organic hydrophobic group in the molecule
The object is an organic titanium compound,
The printing plate material according to claim 13 or claim 14 . 17. A compound having an organic hydrophobic group in the molecule
The object is an organic silane compound,
The printing plate material according to claim 13 or claim 14 . 18. A bandgap of a titanium oxide photocatalyst.
By irradiating light with higher energy than nergi
Therefore, the hydrophobic part that is not illuminated and the hydrophilic part that is illuminated by light
A print that forms a latent image consisting of the part converted to the surface
Ink was removed from the plate surface during the manufacturing process and after printing.
After that, at least in the hydrophilic part of the plate surface,
React or strongly interact with compounds having organic hydrophobic groups
And the process of recycling the printing plate material
The printing plate material according to any one of claims 1 to 5 , wherein the printing plate material can be repeatedly used . 19. A titanium oxide photocatalyst band gap energy
It has a light source containing light with higher energy than
Writing device that draws directly on the printing plate based on digital data
The printing plate material according to any one of claims 1 to 18 , wherein an image can be written by using the printing plate material. 20. The method according to any one of claims 1 to 5.
After printing, place the surface of the coating layer containing titanium oxide photocatalyst
Leaning step followed by titanium oxide photocatalyst
Features and method for regenerating printing plate material you to include at least a step of reproducing coating layer. 21. The method according to any one of claims 1 to 5.
After printing, place the surface of the coating layer containing titanium oxide photocatalyst
The process of leaning and then the irradiation of energy flux
The process of regenerating the coating layer containing the titanium oxide photocatalyst by
Re extent and the printing plate material you characterized by including at least
Raw method . 22. The method according to any one of claims 1 to 5.
After printing, place the surface of the coating layer containing titanium oxide photocatalyst
The process of leaning and the subsequent chemical conversion treatment
The step of regenerating the coating layer containing titanium oxide photocatalyst.
Play sides of the printing plate material you characterized in that it comprises at least
Law . 23. The method according to any one of claims 1 to 5.
After printing, place the surface of the coating layer containing titanium oxide photocatalyst
Leaning process, then irradiation and conversion of energy flux
Titanium oxide photocatalyst is included by performing combined treatments.
Features and method for regenerating printing plate material you to include at least a step of reproducing uncoated layer. 24. The method according to any one of claims 1 to 5.
After printing, place the surface of the coating layer containing titanium oxide photocatalyst
The process of leaning and then adding an organic hydrophobic group in the molecule
By reacting or interacting strongly with
The step of regenerating the coating layer containing titanium oxide photocatalyst.
Play sides of the printing plate material you characterized in that it comprises at least
Law . 25. The surface of the coat layer is cleaned.
25. The process according to any one of claims 20 to 24, wherein the step and the step of regenerating the coat layer are performed on a printing machine.
The method for recycling the printing plate material described in. 26. In the printing plate material according to any one of claims 10 to 12, after printing, at least partially hydrophilic in its plane
Showing the step of cleaning the outermost surface including the surface of the coating layer, and then re-forming the coating layer to reduce the contact angle of water.
A method for recycling a printing plate material, which comprises at least a step of exposing a hydrophobic surface having an angle of 50 ° or more . 27. A step of cleaning the outermost surface
The method for recycling a printing plate material according to claim 26 , wherein the step of reforming the coating layer and the step of reforming the coating layer are performed on a printing machine . 28. A printing plate based on the printing plate material according to any one of claims 1 to 19 and digital data.
Writing device that draws directly on the material and ink after printing
And a printing plate to remove the dust from the plate surface
A printing apparatus comprising: a recycling device for recycling a material . 29. The regenerator comprises an organic hydrophobic group in the molecule.
Oxidation by applying a compound containing
29. The printing device according to claim 28, which is a device for reproducing a coat layer containing a titanium photocatalyst .