JPH10226866A - Production of aluminum alloy sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a producing method capable of inexpensively producing an aluminum alloy sheet obtd. by joining different kinds of material free from peeling at the joined part. SOLUTION: In the method for producing an aluminum alloy sheet 20 by continuously discharging the molten metal of an aluminum alloy from a molten metal feeding nozzle 3, feeding it to the space between a pair of driving cooling dies 4a and 4b and continuously executing casting and rolling, it is fed to the driving cooling dies 4a and 4b in a state in which the molten metal discharged from the molten metal feeding nozzle 3 and a web-shaped aluminum alloy sheet having an alloy compsn. different from that of the molten metal are brought into contact with.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an aluminum alloy plate, and more particularly to a lithographic printing plate support.
The present invention relates to a method for producing an aluminum alloy plate suitable for fin materials, can materials, building materials, mechanical parts, electric parts, and the like.

[0002]

2. Description of the Related Art Conventionally, aluminum alloy plates have been widely used in lithographic printing plate supports and various other fields in view of their workability and strength. For example, Japanese Unexamined Patent Publication (Kokai) No. 61-274993 discloses a technique relating to a support for an aluminum alloy lithographic printing plate manufactured by DC casting and hot rolling using aluminum having a specific alloy component. According to this method, an aluminum alloy support for offset printing having excellent burning resistance and cut-off resistance while maintaining surface treatment properties and printability equivalent to those of the conventional material is obtained. Japanese Patent Application Laid-Open No. 6-48058 discloses a support for an aluminum alloy lithographic printing plate manufactured by continuous casting using aluminum having a specific alloy component. A lithographic printing plate having less variation in materials, improving the yield of electrolytic surface roughening treatment, and having excellent suitability for surface roughening has been obtained.

In the lithographic printing plate support, it is said that the aluminum plate preferably has a higher aluminum purity in view of the adhesion to the photosensitive layer. However, in a lithographic printing plate, it is the surface of the aluminum plate that comes into contact with the photosensitive layer. If the aluminum concentration in the surface layer of the plate is substantially high, the aluminum concentration in the center of the plate or the surface on which the photosensitive layer is not coated is considered. Is unquestioned. Since the higher the purity of aluminum, the higher the material cost, it is more advantageous to use a low-priced material with low aluminum purity except for the surface layer. Further, from the viewpoint of handleability, it is preferable that the plate is lighter in consideration of its excellent mechanical strength as a whole plate, and particularly in consideration of transport by a human. However, when the plate thickness is reduced for weight reduction, mechanical strength is reduced, and bending or in extreme cases, breakage, or local bending portions called knicks are likely to occur.
On the other hand, for automatic plate making, a certain amount of weight is required to prevent vertical movement and left / right swing on the conveyor belt. With respect to such a point, Japanese Patent Application Laid-Open No.
The plate material obtained by the casting method as described in JP-A-749993 or JP-A-6-48058 has a uniform material, cannot be combined with an inexpensive material and cannot adjust the weight, and the management of the alloy composition is complicated. Is a problem.

[0004] Therefore, in order to reduce costs, increase mechanical strength, and improve handleability, composite materials in which different materials are laminated have been proposed. For example, Japanese Patent Publication No. 56-3211
No. 1 discloses a composite material (laminated material) obtained by laminating two kinds of plate materials, which has high water retention, and also improves the adhesion of the photosensitive resin and the inking property of the sensitized product. Also, techniques relating to a method for producing a lithographic composite plate material are disclosed.
Japanese Patent Application Laid-Open No. 58-1047 discloses a printability and strength suitable for high-speed printing, which simultaneously solve the problems of printability, strength and economy by using a composite material (clad rolled material) by clad rolling. A technique relating to a support for an aluminum alloy printing plate excellent in the above is disclosed.

[0005]

However, the bonding material requires an adhesive for bonding and requires a process for bonding, which not only increases the manufacturing cost but also increases the bonding cost. Is an adhesive layer, there is also a problem in terms of peel strength. On the other hand, in the case of a clad rolled material, a step of pressing at a high temperature is required, which leads to an increase in manufacturing cost, and the peel strength is not sufficient because the plate materials are joined by plastic deformation of the surface. As described above, both the bonding material and the rolled clad material have a problem that can be said to be fatal, that is, the production cost and the occurrence of peeling at the joint portion.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a manufacturing method capable of manufacturing an aluminum alloy plate formed by joining dissimilar materials having no peeling at a joining portion at a low cost. I do.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to continuously discharge a molten aluminum alloy from a molten metal supply nozzle and supply the molten metal between a pair of driven cooling molds to continuously cast and roll. In the method of manufacturing an aluminum alloy plate, the molten metal discharged from the molten metal supply nozzle and a web-shaped aluminum alloy plate having an alloy composition different from that of the molten metal are supplied in a state of being in contact with each other between the driving cooling molds. This is achieved by a method of manufacturing a characteristic aluminum alloy plate.

According to the manufacturing method of the present invention, the molten aluminum alloy is continuously discharged from the molten metal supply nozzle, and the discharged molten metal is brought into contact with a web-shaped aluminum alloy plate (hereinafter referred to as an aluminum web). Since it is only necessary to supply between the drive cooling mold in the state of being made, aluminum that is made by joining dissimilar materials at low cost without the need for an adhesive or joining process like bonding material or rolled clad material An alloy plate can be obtained. Further, according to the manufacturing method of the present invention, the high-temperature molten metal discharged from the molten metal supply nozzle comes into contact with the aluminum web, and the two are welded when passing through the driving cooling mold. Therefore, the obtained aluminum alloy plate is a product in which the aluminum alloy portion formed by solidifying the molten metal (hereinafter, referred to as the molten metal solidified portion) and the aluminum web are firmly joined by welding, and a bonding material using an adhesive is used. The peel strength is remarkably improved as compared with a clad rolled material joined by plastic deformation.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a method for manufacturing an aluminum alloy sheet according to the present invention will be described in detail with reference to the drawings.
The production method of the present invention is based on the conventional continuous casting method, but is characterized in that the molten metal and the aluminum web are supplied in a state of contact between a pair of driven cooling molds. As the continuous casting method, a method using a cooling roll as a driving cooling mold as represented by the Hunter method or the 3C method, and a method using a cooling belt as a driving cooling mold as represented by the Hadley method are industrial. However, in the present invention, all of these methods can be adopted.

FIG. 1 is a configuration diagram showing an example of a production apparatus suitable for carrying out the production method of the present invention, and shows a configuration in which a cooling roll is used as a driving cooling mold.
As shown in the figure, the molten metal is sent to the gutter 2 by tilting the melting and holding furnace 1. The liquid level of the gutter 2 is detected by a liquid level sensor 7, and by controlling the melting furnace tilting motor 9 via the amplifier 8, the supply amount of the molten metal is appropriately controlled to maintain the liquid level of the gutter 2 constant. . If necessary, the crystal grain refinement wire 10 is supplied to the molten metal at an appropriate position. The molten metal is continuously discharged from the molten metal supply nozzle 3 at a predetermined speed and sent to a gap between the pair of cooling rolls 4a and 4b. At this time, the aluminum webs 15a and 15b sent from the web supply devices 14a and 14b are continuously supplied to the gap between the cooling rolls 4a and 4b so as to sandwich the molten metal. Then, by passing through the cooling rolls 4a and 4b, the molten metal is solidified and cooled, and at the same time, the molten metal and the aluminum webs 15a and 15b are rolled in a laminated state, whereby the aluminum alloy plate 20 is manufactured. The aluminum alloy plate 20 is wound by the coiler 6 or sampled by the cutter 5 as appropriate. The winding speed of the coiler 6 varies depending on the alloy composition of the molten metal, the desired plate thickness, and the like, but is a speed at which the molten metal can be solidified when passing through the cooling rolls 4a and 4b.

The aluminum alloy plate 2 obtained as described above
0, as shown in the cross-sectional view of FIG. 2, a core 3 having a molten metal solidified portion 21 formed by solidifying the molten metal, with both surfaces sandwiched by aluminum webs 15a and 15b serving as surface layers.
It has a layer structure. Also, this aluminum alloy plate 20
In the above manufacturing process, the high-temperature molten metal immediately after being discharged from the molten metal supply nozzle 3 comes into contact with the aluminum webs 15a and 15b before reaching the cooling rolls 4a and 4b, and three layers are formed by the cooling rolls 4a and 4b. It is cooled and rolled in a laminated state. Therefore, the joining part 22 between the molten metal solidification part 21 and the aluminum webs 15a, 15b is
Since the two are in a welded state and firmly joined, the peel strength of the joint is significantly improved as compared with a bonding material using an adhesive or a clad rolled material joined by plastic deformation. In addition, there is no need for an adhesive or a step for bonding, and the device is manufactured at low cost.

In the above manufacturing method, by changing the alloy composition of the molten metal and the alloy composition of the aluminum webs 15a and 15b, as in the case of the bonding material and the rolled clad material,
The aluminum alloy plate 20 according to the use can be obtained. For example, in order to control the specific gravity of the entire board, using aluminum scrap, recycled metal, waste materials from factories, etc., which are inexpensive but contain many impurity components as molten metal,
A light Li-based aluminum alloy or a heavy Pb-based aluminum alloy can be used, or a molten metal containing an alloy component for obtaining high strength can be used. The aluminum webs 15a and 15b may be made of the same material or different, and are appropriately selected according to the application. In addition, only one of the aluminum webs 15a and 15b may be used. In this case, the aluminum alloy plate has a two-layer structure including a molten metal solidified portion made of a molten metal and an aluminum web.

Further, the aluminum alloy plate 20 is subjected to a treatment for adjusting the plate thickness and strength, or for making the crystal structure uniform, improving the flatness, etc. according to the intended use. For example,
As shown in FIG. 3, the thickness of the aluminum alloy plate 20 is reduced using a cold rolling mill 11 in which rolling rolls are arranged in the thickness direction of the plate.
Continuous annealing device 12a configured to allow the vehicle to continuously travel
Alternatively, as shown in FIG. 5, it is possible to adjust the strength and make the crystal structure uniform by using a batch annealing apparatus 12b capable of accommodating the aluminum alloy plate 20 wound in a roll shape. When it is desired to improve the flatness, as shown in FIG. 6, a straightening device 13 in which a plurality of straightening rolls 13a are arranged along the conveying direction of the aluminum alloy plate 20 is arranged.
Can be used to form a flat plate.

The aluminum alloy plate 20 according to the present invention comprises:
Aluminum-based components such as lithographic printing plate supports, fin materials, can materials, building materials, mechanical parts, capacitor foil materials, electric circuit boards, electric storage parts and other electrical parts.
In particular, it can be widely applied to various types of plate materials requiring high functions on the surface. For example, the fin material is used in a heat exchanger such as a radiator, and is required to have press / punching performance and surface wettability. Also, the can material is used for containers such as beer cans,
Press workability and strength are required. In addition, alumite suitability and strength are required for building materials. In addition, mechanical parts are required to have strength and corrosion resistance. Also. Electrical parts
Used for terminals, heat dissipating members, storage battery members, electrolytic capacitors, etc.
Chemical and electrochemical properties are required. For these applications, by appropriately selecting the molten metal and aluminum web in consideration of the function of the surface layer and the core material and casting, the optimal material suitable for the application can be provided in a small number of steps and with sufficient strength. Can be supplied.

An embodiment in which the support is used as a lithographic printing plate support will be described below. Using the manufacturing apparatus shown in FIG. 1, aluminum waste material, UBC (aluminum can waste), casting waste in a factory,
Aluminum chips 14a, 14b made of a common aluminum alloy conventionally used for a lithographic printing plate support are supplied from the web supply devices 14a, 14b while melting the cutting chips and the like to form a molten metal and discharging the molten metal from the molten metal supply nozzle 3.
Is supplied to the gap between the cooling rolls 4a and 4b together with the molten metal. As the aluminum alloy for the support of the lithographic printing plate, for example, in addition to high-purity aluminum of 99.5% or more of aluminum, JIS A 1050 material, JIS
A 3103 material, JIS A 3005 material, JIS A
1100 materials, JIS A 3004 materials, or alloys to which 5 wt% or less of magnesium is added for the purpose of increasing tensile strength can be used. In addition, as the different element, silicon, iron, nickel, manganese, copper, magnesium, chromium, zinc, bismuth, titanium, vanadium and the like can be considered. The obtained aluminum alloy plate is a composite material having a three-layer structure in which a molten metal solidified portion formed by solidifying the molten metal is used as a core material, and an aluminum web suitable for a lithographic printing plate support is used as a surface material. It is a plate that is firmly joined by welding.

Next, the aluminum alloy sheet was processed by a cold rolling mill, an annealing apparatus, and a straightening apparatus shown in FIGS. 3 to 6 to finish it to a predetermined thickness, for example, about 0.1 to 0.6 mm. After that, a roughening process is performed. Hereinafter, a preferred embodiment of the surface roughening treatment will be described.

[Treatment Step 1 for Lithographic Printing Plate Support] (a) Mechanical Roughening Treatment The surface of the aluminum plate is made to have an average surface roughness of 0.35 to 1.0.
In order to reduce the thickness to μm, JP-A-6-135175,
A mechanical surface roughening treatment described in Japanese Patent Application Publication No. 0-40047 is performed. It is preferably performed before the first-stage electrolytic polishing treatment. It is advantageous to mechanically roughen the surface with a rotating nylon brush roll having a hair diameter of 0.2 to 0.9 mm and a slurry supplied to the surface of the aluminum plate. Of course, a method of spraying a slurry liquid, a method of using a wire brush, or a method of transferring the surface shape of a roll with irregularities to an aluminum plate may be used.
Known abrasives can be used, but silica sand, quartz,
Aluminum hydroxide or mixtures thereof are preferred.

(B) electrolytic polishing treatment in an acidic aqueous solution, or chemical etching treatment in an acid or alkali aqueous solution; The purpose is to obtain a printing plate having a smooth undulation and a good stain performance. At this time, the dissolution amount of the aluminum plate is preferably 1 to ²⁰ g / m ² .

(C) Electrochemical surface roughening treatment using a direct current or an alternating current in an aqueous solution mainly composed of nitric acid or hydrochloric acid. Craters or honeycomb-like pits having an average diameter of about 0.5 to 20 μm are formed on an aluminum surface. For the purpose of producing an area ratio of 30 to 100%. The non-image portion of the printing plate has an effect of preventing stains and improving printing durability.

(D) electrolytic polishing treatment in an acidic aqueous solution or chemical etching treatment in an acid or alkali aqueous solution; This is performed for the purpose of removing the smut component and smoothing the edges of the generated pits and improving the stain performance when the printing plate is obtained. The dissolution amount of the aluminum plate is preferably 0.05 to 5 g / m ² ,
It is more preferable to dissolve 0.1 to 4 g / m ² .

(E) Anodizing treatment Anodizing treatment is performed to increase the abrasion resistance of the surface of the aluminum plate.

[Treatment step 2 for lithographic printing plate support] (a) Electropolishing treatment in an acidic aqueous solution or chemical etching treatment in an acid or alkali aqueous solution Rolling oil on the surface of an aluminum plate In order to remove the natural oxide film, dirt, etc., and to perform electrochemical surface roughening uniformly. Dissolution amount of aluminum plate is 1-30g / m
² is preferably dissolved, more preferably 1.5 to 20 g / m ² .

(B) Electrochemical surface roughening treatment using a direct current or an alternating current in an aqueous solution mainly composed of nitric acid or hydrochloric acid. Craters or honeycomb-like pits having an average diameter of about 0.5 to 20 μm are formed on an aluminum surface. The aluminum plate surface is formed at an area ratio of 30 to 100% and has an average surface roughness of 0.35 to 1.0 μm as measured by an atomic force microscope. The non-image portion of the printing plate has an effect of preventing stains and improving printing durability.

(C) Electropolishing in an acidic aqueous solution, or chemical etching in an acid or alkaline aqueous solution (b) Smut generated by electrochemical surface roughening in (b) and edge portions of pits Alternatively, melting is performed on a plateau portion where no pits are formed to obtain a surface having smooth irregularities. The non-image portion of the printing plate has an effect of preventing stains and improving printing durability. Dissolution amount of aluminum plate is 1
-30 g / m ^2, preferably 1.5-20
g / m ² is more preferably dissolved.

(D) Electrochemical surface roughening treatment using a direct current or an alternating current in an aqueous solution mainly containing nitric acid or hydrochloric acid. Craters or honeycomb-like pits having an average diameter of about 0.5 to 20 μm are formed on an aluminum surface. For the purpose of producing an area ratio of 30 to 100%. The non-image portion of the printing plate has an effect of preventing stains and improving printing durability.

(E) Electrolytic polishing in an acidic aqueous solution or chemical etching in an acid or alkaline aqueous solution (b) Aluminum hydroxide produced by electrochemical surface roughening in (b) This is performed for the purpose of removing the smut component and smoothing the edges of the generated pits and improving the stain performance when the printing plate is obtained. The dissolution amount of the aluminum plate is preferably 0.05 to 5 g / m ² ,
It is more preferable to dissolve 0.1 to 3 g / m ² .

(F) Anodizing treatment Anodizing treatment is performed to increase the abrasion resistance of the surface of the aluminum plate.

[Treatment step 3 for lithographic printing plate support] (a) Electropolishing treatment in acidic aqueous solution or chemical etching treatment in acid or alkali aqueous solution Rolling oil on the surface of aluminum plate , Natural oxide film, dirt, etc. are removed, and the surface is electrochemically roughened. Dissolution amount of aluminum plate is 1-30g / m
² is preferably dissolved, more preferably 1.5 to 20 g / m ² .

(B) Electrochemical surface roughening treatment using DC or AC in an aqueous solution mainly containing nitric acid or hydrochloric acid Electricity using DC or AC in an aqueous solution mainly containing hydrochloric acid or nitric acid The chemical surface roughening treatment has an average diameter of about 0.5 mm.
Craters or honeycomb pits of 5 to 20 μm are formed on the aluminum surface at an area ratio of 30 to 100%,
The purpose is to make the surface of the aluminum plate measured by an atomic force microscope have an average surface roughness of 0.35 to 1.0 μm. The non-image portion of the printing plate has an effect of preventing stains and improving printing durability.

(C) electrolytic polishing in an acidic aqueous solution,
Or chemical etchin in aqueous acid or alkali solution
(B) electrochemical surface roughening using DC or AC
A smut composition mainly composed of aluminum hydroxide
And smooth the edges of the generated pits
To improve the stain performance of the printing plate.
U. Dissolution amount of aluminum plate is 0.05-5g / m^TwoDissolution
Preferably 0.1 to 3 g / m ^TwoDissolve
Is more preferable.

(D) Anodizing treatment Anodizing treatment is performed to increase the abrasion resistance of the surface of the aluminum plate.

The details of each processing step for the lithographic printing plate support described above will be described below.・ Electropolishing of aluminum plate in acidic aqueous solution or chemical etching of aluminum plate in acidic or alkaline aqueous solution

Electrolytic polishing of aluminum plate in acidic aqueous solution Fujio Mamiya: Cleaning Design No. 21, p65-72 (1
984) describes a prescription example by material for the electropolishing treatment. A known aqueous solution used for electropolishing can be used. An aqueous solution mainly containing sulfuric acid or phosphoric acid is preferred, and an aqueous solution mainly containing phosphoric acid is particularly preferred. Phosphoric acid 20-90 wt% (preferably 40-80 w
t%), and the liquid temperature is 10 to 90 ° C (preferably 50 to 80 ° C).
° C.), a current density 1~100A / dm ² (preferably 5 to
80 A / dm ² ) and the electrolysis time can be selected from the range of 1 to 180 seconds. Sulfuric acid, chromic acid, hydrogen peroxide, citric acid, boric acid, hydrofluoric acid, phthalic anhydride, etc. may be added to the phosphoric acid aqueous solution at 1 to 50 wt%. In addition to aluminum, an alloy component contained in an aluminum alloy may be contained in an amount of 0 to 10 wt%.

As the current, DC, pulse DC, and AC can be used, but continuous DC is preferable. As the electrolytic treatment apparatus, those used in known electrolytic treatment such as a flat type tank and a radial type tank can be used. The flow rate may be either parallel flow or counter flow with respect to the aluminum plate, and is selected from the range of 0.01 to 10000 cm / min. The distance between the aluminum plate and the electrode is 0.
It is preferably 3 to 10 cm, particularly preferably 0.8 to 2 cm. As a power supply method, a direct power supply method using a conductor roll may be used, or an indirect power supply method (liquid power supply method) without using a conductor roll may be used. As the electrode material and structure to be used, known materials used for electrolytic treatment can be used, but the cathode material is preferably carbon, and the anode material is preferably ferrite, iridium oxide or platinum. The processing surface of the aluminum plate may be the upper surface, the lower surface, or both surfaces.

Chemical etching of an aluminum plate in an aqueous acid or alkali solution For details of such an etching method, see US Pat.
No. 34398, and known means can be used. As the acid or alkali which can be used for the acidic aqueous solution, those described in JP-A-57-16918 and the like can be used alone or in combination. The treatment is preferably performed at a liquid temperature of 40 to 90 ° C. for 1 to 120 seconds. The concentration of the acidic aqueous solution is 0.5 to
The content of aluminum dissolved in the acidic aqueous solution is preferably 0.5 wt% to 5 wt%.

The concentration of the aqueous alkali solution is preferably 5 to 30% by weight, and the amount of aluminum dissolved in the aqueous alkaline solution is preferably 1 to 30% by weight. After the completion of the etching process, it is preferable to perform draining with a nip roller and washing with water by spraying so as not to bring the processing solution into the next step. When chemical etching is performed using an aqueous solution of a base, a smut is generally formed on the surface of aluminum. In this case, phosphoric acid, nitric acid, sulfuric acid, chromic acid, hydrochloric acid, or a mixture of two or more of these acids is used. Treat with mixed acid. Further, 0 to 5 wt% of aluminum may be dissolved in the acidic aqueous solution.

The solution temperature is from room temperature to 70 ° C., and the processing time is preferably from 1 to 30 seconds. After the end of the desmutting treatment, it is preferable to perform draining with a nip roller and washing with water by spraying so as not to bring the treatment liquid into the next step. Further, an overflow waste liquid of the electrolytic solution used in the electrochemical surface roughening treatment can be used. When using the overflow waste liquid of the electrolytic solution used in the electrochemical surface roughening treatment, the water washing treatment after the desmutting treatment may be omitted, but the aluminum plate is dried so that the components in the desmutting solution do not precipitate. You need to be careful.

Electrochemical surface roughening treatment using a direct current or an alternating current in a hydrochloric acid or nitric acid aqueous solution Electrochemical surface roughening treatment using a direct current What is used for the electrochemical surface roughening treatment used can be used,
1 g of at least one of a hydrochloric acid or a nitric acid compound having a nitric acid ion such as aluminum nitrate, sodium nitrate, ammonium nitrate, or a hydrochloric acid ion such as aluminum chloride, sodium chloride, ammonium chloride, etc., in an aqueous solution of hydrochloric acid or nitric acid of 1 to 100 g / l. / L to saturation. In addition, metals contained in aluminum alloys such as iron, copper, manganese, nickel, titanium, magnesium, and silica may be dissolved in an aqueous solution mainly containing hydrochloric acid or nitric acid. Preferably, an aluminum ion in a 0.5 to 2 wt% aqueous solution of hydrochloric acid or nitric acid contains 3 to 3 aluminum ions.
It is preferable to use a solution to which aluminum chloride and aluminum nitrate are added so as to be 50 g / l. Temperature is 1
0-60 degreeC is preferable and 25-50 degreeC is more preferable.

As a processing apparatus used for electrochemical surface roughening using a direct current, a known apparatus using a direct current can be used. As described in Japanese Patent Application Laid-Open No. 1-141094, one or more pairs of processing apparatuses can be used. It is preferable to use a device in which the anode and the cathode are alternately arranged. Examples of known devices include Japanese Patent Application Nos. 5-68204, 6-205657, 6-205.
21050, Japanese Patent Application No. 61-19115 and Japanese Patent Publication No. 57-44760. After the completion of the electrolytic treatment, it is preferable to perform draining with a nip roller and washing with water by spraying so as not to bring the treatment liquid into the next step.

It is preferable to use a direct current having a ripple ratio of 20% or less as the direct current used for electrochemical surface roughening. The current density is preferably 10 to 200 A / dm ² , and the quantity of electricity when the aluminum plate is an anode is 100 to 1000 C / dm ^2.
Is preferred. The anode can be selected from known oxygen generating electrodes such as ferrite, iridium oxide, platinum, and a valve metal such as titanium, niobium, and zirconium clad or plated with platinum. The cathode can be selected from carbon, platinum, titanium, niobium, zirconium, stainless steel, and an electrode used for a fuel cell cathode.

Electrochemical surface roughening using alternating current As the aqueous solution mainly composed of hydrochloric acid or nitric acid, one used for usual electrochemical surface roughening using alternating current can be used.
1 g of at least one of a hydrochloric acid or a nitric acid compound having a nitric acid ion such as aluminum nitrate, sodium nitrate, ammonium nitrate, or a hydrochloric acid ion such as aluminum chloride, sodium chloride, ammonium chloride, etc., in an aqueous solution of hydrochloric acid or nitric acid of 1 to 100 g / l. / L to saturation. In addition, metals contained in aluminum alloys such as iron, copper, manganese, nickel, titanium, magnesium, and silica may be dissolved in an aqueous solution mainly containing hydrochloric acid or nitric acid. Preferably, an aluminum ion in a 0.5 to 2 wt% aqueous solution of hydrochloric acid or nitric acid contains 3 to 3 aluminum ions.
It is preferable to use a solution to which aluminum chloride and aluminum nitrate are added so as to be 50 g / l. Temperature is 1
0-60 degreeC is preferable and 25-50 degreeC is more preferable.
In electrochemical surface roughening in an aqueous solution mainly composed of nitric acid, pits having an average diameter of 0.5 to 3 μm have a size of 1 × 10 ⁵ to 6 ×.
It is preferable that pits are generated at a rate of 10 ⁶ / mm ² . However, when the amount of electricity is relatively large, the electrolytic reaction concentrates and honeycomb pits exceeding 3 μm are also generated.

In electrochemical surface roughening in an aqueous solution mainly containing hydrochloric acid, 0.1 to 0.4 μm is superposed on a large crater-like or honeycomb-like undulation having an average diameter of 2 to 20 μm.
Cubic pits of μm square are uniformly formed on the entire surface. 500 to 300,000 crater-shaped pits /
It is preferable that the particles are formed at a density of mm ² . A sine wave, a rectangular wave, a trapezoidal wave, a triangular wave, or the like is used as an AC power supply waveform used for electrochemical roughening. For electrochemical surface roughening in an aqueous nitric acid solution, a rectangular wave or a trapezoidal wave is preferable, and a trapezoidal wave is particularly preferable. In a trapezoidal wave, the current is 0
From time to peak to TP is 0.5 to 3 ms
c is preferred. Sine wave, rectangular wave, trapezoidal wave, and triangular wave are preferable for electrochemical surface roughening in an aqueous nitric acid solution.
Select according to the desired surface shape. For electrochemical surface roughening in an aqueous hydrochloric acid solution, trapezoidal waves, sine waves, and triangular waves are preferable, and trapezoidal waves and triangular waves are particularly preferable. Time TP until the current reaches a peak from 0 in trapezoidal and triangular waves
Is 0 to 50%, more preferably 1 to 30%, especially 1 to 10% of the time when the aluminum plate is the anode in one cycle of the current waveform.
% Is preferred.

The time TH during which the peak of the current waveform at the time of the anode of the aluminum plate in the trapezoidal wave is maintained is 1 to 50 times the cycle of the aluminum plate as the anode in one cycle of the current waveform.
%, More preferably 1 to 30%, particularly preferably 1 to 10%. The power supply waveform used for electrochemical surface roughening in an aqueous solution mainly composed of nitric acid or hydrochloric acid has a duty ratio of 1: 2.
２2: 1 is preferable, and in view of the cost of the power supply body, du
A ty ratio of 1: 1 is particularly preferred. The frequency is 0.1
~ 120 Hz can be used, but 20 Hz
-70 Hz is preferable in terms of equipment. However, when an aluminum alloy containing more than 0.1 wt% of Cu is used for electrochemical surface roughening in a nitric acid aqueous solution, the frequency is 0.1 to 10 Hz, particularly 0.3 to 1.2 Hz. Preferably, an alternating current is used.

The current density is 10 to 2 as the peak value of the current waveform.
00 A / dm ² is preferred. As an electrolytic cell used for electrochemical surface roughening using an alternating current, an electrolytic cell used for a known surface treatment such as a vertical type, a flat type, and a radial type can be used, which is described in JP-A-5-195300. Such a radial electrolytic cell is particularly preferred. The electrolytic solution passing through the electrolytic cell may be parallel or counter to the progress of the aluminum web. One or more AC power supplies can be connected to the electrolytic cell. The purpose is to control the current ratio of the AC anode and cathode applied to the aluminum plate facing the main pole, to perform uniform graining, and to dissolve the carbon of the main pole.
It is preferable to provide an auxiliary anode and divide a part of the alternating current. An anodic reaction acting on an aluminum plate facing the main electrode by diverting a part of the current value as a direct current to an auxiliary anode provided in a tank separate from the two main electrodes via a rectifying element or a switching element. And the ratio of the current value participating in the cathode reaction to the current value participating in the cathode reaction can be controlled. It is preferable that the amount of electricity participating in the anodic reaction and the amount of electricity participating in the cathodic reaction acting on the aluminum plate facing the main electrode be 0.3 to 0.95.

Anodizing treatment Anodizing treatment is performed to increase the abrasion resistance of the surface of the aluminum plate. As the electrolyte used for the anodic oxidation treatment of the aluminum plate, any electrolyte that forms a porous oxide film can be used. Generally, nitric acid, phosphoric acid, oxalic acid, chromic acid, or a mixture thereof is used. The concentration of these electrolytes is appropriately determined depending on the type of the electrolyte. Since the anodizing treatment conditions vary depending on the electrolyte used, they cannot be specified unconditionally. Generally, however, the concentration of the electrolyte is 1 to 80 wt%, the liquid temperature is 5 to 70 ° C., the current density is 1 to 60 A / dm ² , and the voltage is 1 to 1
It is appropriate that the electrolysis time is in the range of 00 V and the electrolysis time is 10 seconds to 300 seconds. In the nitric acid method, the treatment is usually performed with a direct current, but an alternating current can also be used. The amount of anodized film is 1 ~
A range of 10 g / m ² is appropriate. When the amount is less than 1 g / m ² , the printing durability is insufficient, and the non-image portion of the lithographic printing plate is easily damaged, and at the same time, the ink adheres to the scratched portion, that is, so-called scratch stain is easily generated. .

Hydrophilic treatment after forming anodized film After the anodizing treatment, the aluminum surface is subjected to a hydrophilizing treatment as necessary. U.S. Pat. Nos. 2,714,066 and 318 as hydrophilic treatments used in the present invention.
No. 1461, No. 3280734 and No. 3902732
There is an alkali metal silicate (for example, sodium silicate aqueous solution) method as disclosed in each of the above-mentioned specifications. In this method, the support is immersed in an aqueous solution of sodium silicate or electrolytically treated. In addition, Japanese Patent Publication No. 36-22
No. 063, potassium fluoride zirconate, and US Pat. Nos. 3,276,868 and 4,153.
For example, a method of treating with polyvinyl phosphonic acid as disclosed in each of JP-A Nos. 461 and 4689272 can be used. After graining and anodizing,
Those subjected to a sealing treatment are also preferable. Such a sealing treatment is performed by immersion in hot water and a hot aqueous solution containing an inorganic salt or an organic salt, a steam bath or the like.

Others On the lithographic printing plate support thus obtained,
By providing a conventionally known photosensitive layer, a photosensitive lithographic printing plate can be obtained, and the lithographic printing plate obtained by performing plate making processing has excellent performance. The photosensitive substance used in the photosensitive layer is not particularly limited, and those usually used for photosensitive lithographic printing plates can be used. For example, various types described in JP-A-6-135175 can be used. The aluminum plate is provided with an organic undercoat layer (intermediate layer) if necessary before coating the photosensitive layer. As the organic undercoat layer provided on the undercoat layer, those conventionally known can be used, and for example, those described in JP-A-6-135175 can be used. The photosensitive layer may be a negative type or a positive type.

(Examples) The present invention can be further clarified by the following examples. However, the present invention is not limited by these examples.

Each embodiment was carried out using the manufacturing apparatus shown in FIG. First, aluminum scrap material, factory waste material, and UBC (waste aluminum can) were melted in a melting furnace to prepare an aluminum melt containing many impurities. The sample thus prepared was sampled and solidified, followed by JIS H13
Quantitative analysis was performed using an emission spectrometer in the same manner as the method specified in No. 03, and the alloy components were analyzed. Table 1 shows the results.

[0050]

[Table 1]

Subsequently, the molten metal was supplied to the molten metal supply nozzle 3 of the production apparatus shown in FIG. 1, and a casting plate consisting of the molten metal was produced at a casting speed of 0.4 m / min. One minute after casting this cast plate, the casting speed was increased to 0.7 m / min, and after one minute, the web 15a made of 0.3 mm thick A1050 material was fed from the web supply devices 14a, 14b. Fifteen
b was continuously sent out and supplied to the cooling rolls 4a and 4b while the molten metal was sandwiched between the webs 15a and 15b. In this way, a plate having a surface layer of A1050 material and a thickness of 7 mm was manufactured. The alumite treatment was performed on the 7 mm plate to obtain Example-1.

Further, this 7 mm plate was not subjected to alumite treatment, but was rolled to a thickness of 1 mm by a cold rolling mill 11 shown in FIG. 3, and was further subjected to intermediate annealing by a continuous annealing device 12a shown in FIG. Performed at 450 degrees for 1 minute. Then, it was finished to a thickness of 0.24 mm again by the cold rolling mill 11, and the flatness was corrected by the straightening device 13 shown in FIG. This 0.24m
m was mechanically, chemically and electrochemically roughened to obtain a lithographic printing plate support. The lithographic printing plate support thus produced was designated as Example-2.

The aluminum webs 15a, 15b
Was supplied, and a 7 mm plate made of only the molten metal was subjected to alumite treatment to obtain Comparative Example-1. Also, a 7 mm plate made of only molten metal is used as a core material, and a 0.3 mm thick A
An aluminum plate made of 1050 material was clad and rolled as a surface material, and a 6-mm plate prepared by alumite treatment was used as Comparative Example-2.

Similarly, a 7 mm plate made of only the molten metal was not subjected to the alumite treatment, and the cold rolling mill 11 shown in FIG.
Then, rolling was performed to a thickness of 1 mm, and intermediate annealing was performed at a temperature of 450 ° C. for 1 minute using a continuous annealing apparatus 12a shown in FIG.
Then, it was finished again to a thickness of 0.24 mm by the cold rolling mill 11, and the flatness was corrected by the straightening device shown in FIG. This 0.24 mm plate was subjected to mechanical, chemical and electrochemical surface roughening treatments to obtain a lithographic printing plate support. The lithographic printing plate support thus produced was referred to as Comparative Example-3. 6 mm produced by clad rolling of Comparative Example-2
No plate was subjected to an alumite treatment, and a lithographic printing plate support was produced in the same manner as in Comparative Example-3, and Comparative Example-4 was obtained.

Example 1, Comparative Example 1 and Comparative Example-2
The manufacturing method according to the present invention, and the aluminum plate according to the manufacturing method is subjected to machining such as building materials, machine parts, food containers, etc., materials requiring appearance quality when subjected to anodizing, or bending. It was produced to determine whether or not it was excellent as a material. About the board | substrate of Example 1, the comparative example 1, and the comparative example 2, the external appearance after alumite processing and the suitability to bending were evaluated. Table 2 shows the results.

[0056]

[Table 2]

In Example 1 of the present invention, the appearance after the alumite treatment was excellent, and the bending property was comparative example-2.
It was found to be superior to the rolled clad material. It has been found that, when the bending process is repeated, the clad rolled material peels off from the surface material and the core material.

Example 2 and Comparative Example 3 were prepared by the production method of the present invention with a thickness of 0.2% having an A1050 material component in the surface layer.
4mm thin plate and 0.24mm thick surface layer with many impurities
Was prepared in order to confirm the difference in performance when the thin plate was used as a support for a lithographic printing plate. The appearance after the surface roughening treatment of Example-2 and Comparative Example-3 was compared, and the pit shape generated on the surface of the plate was observed using a scanning electron microscope (abbreviation: SEM). Further, a photosensitive layer was applied to the surface of the plate, and the performance as a printing plate was evaluated. The printing performance was evaluated by printing the same image on the printing plate of Example-2 and Comparative Example-3, attaching the same image to the plate cylinder of a printing press, and printing the image. Were compared. Table 3 shows the results.

[0059]

[Table 3]

In Example 2 of the present invention, the pit shape when the surface roughening treatment was performed was uniform, so that the printing performance was good and the appearance after the surface roughening treatment was also good. On the other hand, Comparative Example-3 was inferior to Example-2 in all items. Moreover, Example-2 and Comparative Example-3
The surface of the electronic probe micro analyzer (abbreviation: EP)
MA. Elemental analysis was performed using JEOL (8800M type). In Comparative Example-3, Fe, C contained in the molten metal were used.
While alloy components such as u, Mn, Zn, and Si are unevenly distributed, in Example-2, JIS welded to the surface layer was used.
Since the effect of the 1050 material was large, non-uniform distribution of alloy components was not observed. Regarding the printing performance, the printing plate of Example-2 did not show any missing portion even after printing 100,000 sheets, but the printing plate of Comparative Example-3 showed no missing portion after printing 20,000 sheets. Occurred. This indicates that the aluminum plate according to the present invention is suitable as a support for a lithographic printing plate.

Next, the plates of Example-2 and Comparative Example-4 were set to the width 2
0mm, cut into 100mm long strips, 10
A metal fitting was attached to each mm, and a bending load having an amplitude of 10 mm was applied at a cycle of 10 times per second while a tensile load of 300 g was applied, and the number of times until the cutting was satisfied due to bending fatigue was examined. The result was 60,000 times in Example-2 and 18 in Comparative Example-4.
2,000 times, indicating that Example-2 of the present invention had excellent fatigue strength against repeated bending. This means
This means that when the lithographic printing plate is mounted on a printing press and a large amount of printing is performed, the phenomenon of so-called "out of grip", in which the printing plate is broken at a mounting portion on the plate cylinder, is less likely to occur.
On the other hand, in Comparative Example-4, when the fractured portion was observed, it was found that peeling between the surface layer material and the core material had occurred. It is considered that the separation between the surface layer material and the core material caused the fatigue strength against repeated bending to be significantly reduced.

[0062]

As described above, according to the production method of the present invention, dissimilar materials can be joined at low cost without the need for an adhesive or a joining step as in the case of a bonded material or a rolled clad material. An aluminum alloy plate can be obtained. Further, the aluminum alloy plate obtained by the production method of the present invention has a remarkably improved peel strength as compared with a bonding material using an adhesive or a clad rolled material joined by plastic deformation.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a main part showing a configuration of an embodiment of an apparatus for performing a manufacturing method of the present invention.

FIG. 2 is an enlarged schematic diagram of a cross section of an aluminum alloy plate obtained by the manufacturing method of the present invention.

FIG. 3 is a schematic view showing one embodiment of a cold rolling mill used in the present invention.

FIG. 4 is a schematic diagram showing one embodiment of a heat treatment apparatus used in the present invention.

FIG. 5 is a schematic view showing another embodiment of the heat treatment apparatus used in the present invention.

FIG. 6 is a schematic view of one embodiment of a straightening device used in the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Melting holding furnace 2 Gutter 3 Molten supply nozzle 4a, 4b Cooling roll 11 Cold rolling mill 12a Continuous annealing device 12b Batch annealing device 13 Straightening device 14a, 14b Web supply device 15a, 15b Aluminum web 20 Aluminum alloy plate 21 Melt solidification part 22 Joint

Claims (1)

[Claims] 1. A method for manufacturing an aluminum alloy plate by continuously discharging a molten aluminum alloy from a molten metal supply nozzle, supplying the molten metal between a pair of driving cooling molds, and continuously casting and rolling the aluminum alloy plate. With the molten metal that has been discharged,
A method for producing an aluminum alloy sheet, comprising supplying a web-shaped aluminum alloy sheet having an alloy composition different from that of a molten metal in a state of being in contact with a driving cooling mold.