JP4707700B2 - Metal foil laminate for etching and method for producing etched metal foil - Google Patents

Description

  The present invention relates to a metal foil laminate for etching and a method for producing an etched metal foil.

  A conventional method for producing an etched metal foil is, for example, by performing gravure printing with an ultraviolet curable resist ink containing an alkali-soluble resin on one surface of a metal foil to form a resist layer with a predetermined pattern, and then irradiating it with ultraviolet rays. In this method, acid etching is performed, and then the resist layer is peeled and removed in an alkaline aqueous solution (see, for example, Patent Document 1). That is, the conventional method requires two types of solutions, an acidic solution and an alkaline aqueous solution.

However, in the method as described above, 1) the steps must be separated in order to use two types of solutions, 2) the solution management becomes complicated, and 3) facilities for each solution are required. 4) There are problems such as an increase in total cost.
JP 2000-192260 A

  Thus, in the method using two types of solutions, further improvement is required for the above-described points.

  Therefore, the main object of the present invention is to provide etched metal foil more efficiently on an industrial scale.

As a result of intensive studies to solve the problems of the prior art, the present inventor has found that the above object can be achieved by using a laminate having a specific resist layer, and has completed the present invention. .
That is, this invention concerns on the manufacturing method of the following metal foil laminated body for etching, and etched metal foil.

  1. A metal foil laminate for etching in which a resist layer made of a resist solution containing a polyester resin and an isocyanate curing agent is formed on a part or all of the metal foil.

  2. Item 4. The metal foil laminate for etching according to Item 1, wherein the polyester resin is contained in an amount of 44 to 99.7% by weight based on the total amount of the polyester resin and the isocyanate curing agent.

  3. Item 3. The metal foil laminate for etching according to Item 1 or 2, wherein the polyester resin has a molecular weight of 15,000 to 25,000.

  4). Item 4. The metal foil laminate for etching according to any one of Items 1 to 3, wherein the glass transition point of the polyester resin is 5 to 70 ° C.

  5. Item 5. The metal foil laminate for etching according to any one of Items 1 to 4, wherein the isocyanate compound in the isocyanate curing agent has a molecular weight of 300 to 1,000.

  6). Item 6. The metal foil laminate for etching according to any one of Items 1 to 5, wherein the resist solution further contains an inorganic powder.

  7. After forming a resist layer on part or all of the metal foil using a resist solution containing a polyester-based resin and an isocyanate-based curing agent, and after the resist layer is cured, the etching treatment of the metal foil in one etching solution and A method for producing an etched metal foil in which the resist layer is sequentially peeled off.

  8). The etching metal foil laminate according to any one of Items 1 to 6 is used, and after the resist layer is cured, the metal foil etching process and the resist layer peeling process are sequentially performed in one etching solution. Manufacturing method of etched metal foil.

  9. Item 7. The metal foil laminate for etching according to any one of Items 1 to 6, which is used for sequentially performing a metal foil etching process and a resist layer peeling process in one etching solution after the resist layer is cured.

  10. Item 6. The metal foil laminate for etching according to any one of Items 1 to 5, wherein the polyester resin is a saturated polyester or a modified polyester thereof.

1. Metal foil laminate for etching In the metal foil laminate for etching of the present invention, a resist layer made of a resist solution containing a polyester-based resin and an isocyanate-based curing agent is formed on a part or all of the metal foil.

<Metal foil>
The metal foil used in the present invention is not particularly limited, and includes an alloy foil and the like in addition to a single metal foil. For example, aluminum, copper, iron, titanium, tin, alloys containing these (steel, stainless steel, etc.), and the like can be given.

  In the present invention, the metal foil is preferably an aluminum foil (pure aluminum foil) or an aluminum alloy foil. The aluminum alloy foil preferably contains at least one metal component of Fe, Si, Cu, Ni, Cr, Ti, Zr, Zn, Mn, Mg, and Ga. These metal components may have a predetermined content defined by JIS or the like.

  Specifically, these aluminum foils or aluminum alloy foils include pure aluminum (JIS (AA) 1000 series, such as 1N30, 1N70, 1N90, etc.), Al-Mn series (JIS (AA) 3000 series, such as 3003, 3004, etc. Etc.), Al-Mg system (JIS (AA) 5000 system), Al-Fe system (JIS (AA) 8000 system, such as 8021, 8079, etc.). The aluminum foil or aluminum alloy foil may be any of a hard material, a semi-hard material, a soft material, etc., but a soft material (especially at least one heat treatment (preferably 200 to 500 ° C.) after rolling). (Applied soft material) is preferred.

  The thickness of the metal foil of this invention is not specifically limited, What is necessary is just to set suitably according to the use, usage method, etc. of a final product. In general, the thickness is preferably 4 to 300 μm.

  In the present invention, the metal foil may have one or more third layers such as a resin film layer separately from the resist layer. For example, one or more of polyamide (nylon), polyethylene (including stretched polyethylene, high-density polyethylene, etc.), polyethylene naphthalate, polyethylene terephthalate (including amorphous PET), and polyvinyl chloride are preferably used. be able to. The thickness of the third layer is usually about 9 to 50 μm.

  The formation method of a 3rd layer is not limited, It can implement according to a well-known method. For example, 1) a dry lamination method using a two-component curable urethane adhesive such as a polyester urethane type or a polyester type, 2) a coextrusion method, 3) an extrusion coating method, 4) a thermal lamination method, etc. can be applied. In this case, an anchor coat process, a primer coat process, etc. can be applied to the adhesive surface of the metal foil in advance as required.

  The form of the third layer may be such that part or all of the metal foil can be etched. For example, a 3rd layer (resin film layer etc.) can be provided with a form as shown in FIGS.

<Resist solution>
In the present invention, a resist solution containing a polyester resin and an isocyanate curing agent is used to form a resist layer.

  The type of polyester resin is not particularly limited as long as it is cured by the isocyanate curing agent to be used, and known or commercially available ones can also be used. As the polyester-based resin, for example, saturated polyester (linear saturated polyester) or a modified polyester thereof (modified ether type polyester or the like) can be preferably used. These polyesters may be copolymers obtained by combining two or more monomers. Of these polyesters, polyester resins having hydroxy groups at least in two or more positions in the molecule are preferred.

  Examples of linear saturated polyesters include alcohol components (ethylene glycol, propylene glycol, 1,4-butadiol, 1,4-dicyclohexane dimethanol and the like) and dicarboxylic acid components (aliphatic dicarboxylic acids such as adipic acid and sebacic acid, And an aromatic dicarboxylic acid such as terephthalic acid, isophthalic acid and diphenylcarboxylic acid). More specifically, a copolymer of ethylene glycol and terephthalic acid, a copolymer of ethylene glycol, isophthalic acid and terephthalic acid, a copolymer of 1,4-dicyclohexanedimethanol, isophthalic acid and terephthalic acid And a copolymer of propylene glycol, isophthalic acid and terephthalic acid.

  Other saturated polyester resins include, for example, saturated polybasic acid components (phthalic acid, isophthalic acid terephthalic acid, maleic acid, maleic acid derivatives, succinic acid, adipic acid, sebacic acid, etc.) and polyhydric alcohol components (ethylene glycol). , Diethylene glycol, glycerin, trimethylolpropane, 1-2 propylene glycol, 1-3 butanediol, dipropylene glycol, 1-4 butanediol, 1-6 hexanediol, pentaerythritol, sorbitol, neopentyl glycol, 1-4 Examples thereof include a polymer obtained by an ester bond with cyclohexanedimethanol or the like.

  The polyester resin of the present invention preferably has a glass transition point (Tg) of 5 to 70 ° C. (particularly 10 to 60 ° C.). When set within the above range, the blocking phenomenon can be avoided more reliably, and the resist layer can be peeled off more efficiently.

  In addition, the polyester resin of the present invention preferably has a molecular weight of 15,000 to 25,000. If the molecular weight is set within the above range, the resist layer can be more easily removed after the metal foil etching process.

  The content of the polyester resin may be appropriately determined according to the type of the polyester resin to be used, the use of the laminated body, and the like, but in particular, 44 to 99. with respect to the total amount of the polyester resin and the isocyanate curing agent. What is necessary is just to make it 7 weight% (solid content conversion). By setting to such a range, more excellent curing performance, easy peelability, and the like can be achieved.

  The isocyanate curing agent is not particularly limited, and known or commercially available ones can be used. For example, a curing agent containing an isocyanate compound such as toluene diisocyanate or diphenylmethane diisocyanate as the aromatic isocyanate; hexanemethylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, or tetramethylxylylene diisocyanate as the aliphatic isocyanate can be used.

  Although the molecular weight of the said isocyanate compound is not specifically limited, It is preferable to set it as 300-1000.

  The content of the isocyanate curing agent may be appropriately determined according to the type of the isocyanate curing agent to be used, the use of the laminate, and the like. What is necessary is just to make it become 3 to 56 weight% (solid content conversion).

  In the present invention, other additives may be contained in the resist solution as necessary. For example, resist layer blocking resistance (the ability to prevent the layers from adsorbing to each other when they are wound into rolls or stacked together and stacked) In order to enhance the above, an inorganic powder may be included. For example, one kind or two or more kinds of powders such as talc, alumina, silicon oxide, titanium oxide, calcium carbonate, and barium sulfate can be used. Of these, talc is preferred. The average particle size of these powders is not limited, but may be about 0.1 to 20 μm.

  The content of the inorganic powder can be appropriately determined according to the performance of the desired resist layer, etc., but is 5 parts by weight or less, particularly 0.5 to 5 parts per 100 parts by weight of the total amount of the polyester resin and the isocyanate curing agent. It is desirable to use parts by weight.

  In the resist solution of the present invention, a solvent can be used as necessary. For example, organic solvents such as toluene, methyl ethyl ketone, thinner, acetone, benzine, isopropyl alcohol, methyl acetate, ethyl acetate, and hexane can be used. These can be used alone or in combination of two or more. What is necessary is just to set the usage-amount of a solvent suitably according to the kind of polyester-type resin etc. to be used, the thickness of a desired resist layer, etc.

  Moreover, in this invention, you may contain additives other than the said inorganic powder in a resist liquid as needed. For example, a color pigment, a viscosity modifier, a curing accelerator, a dispersant, an anti-settling agent, an antifoaming agent, a corrosion inhibitor, a surface conditioner, and the like can be appropriately added as long as the effects of the present invention are not impaired.

<Formation of resist layer>
The resist layer may be formed on a part or all of the metal foil using the resist solution. What is necessary is just to implement the formation method according to a well-known method. For example, in addition to application with a brush, spray, roller, doctor blade, bar coater, etc., various printing methods can also be used. In the case of printing, for example, letterpress printing, screen printing, offset printing, gravure printing, etc. can be applied.

  The formed resist layer is cured with time. Curing of the resist layer proceeds even at room temperature, but it can also be accelerated by heating. For example, it can be cured by holding at about 30 to 120 ° C. for 1 minute to 240 hours.

Although the thickness of the resist layer (after curing) of the present invention can be appropriately determined according to the etching conditions, the use of the laminate, etc., it is usually desirable to be 0.3 to 20 μm.
2. Etching metal foil manufacturing method The manufacturing method of the present invention is to form a resist layer on part or all of the metal foil using a resist solution containing a polyester resin and an isocyanate curing agent, and after the resist layer is cured, The metal foil etching process and the resist layer peeling process are sequentially performed in one liquid (in the etching liquid).

  Among the production methods of the present invention, the steps up to 1. It can implement according to description of the metal foil laminated body for an etching. That is, in the present invention, it is desirable that the etching metal foil laminate is used, and after the resist layer is cured, the metal foil etching process and the resist layer peeling process are sequentially performed in an etching solution. Note that a drying process may be provided between the etching process and the peeling process to perform both processes intermittently. Further, the etching process and the peeling process may be performed in different tanks as long as one etching solution is used.

As the liquid (etching liquid) for performing the etching process and the peeling process, an acidic solution or an alkaline solution (aqueous solution) such as hydrochloric acid, hydrofluoric acid, phosphoric acid, oxalic acid, sulfuric acid, ferric chloride aqueous solution, caustic soda, or the like is used. it can. The concentration of these solutions may be appropriately set according to the type of the laminated body, but is usually about 1 to 30% by weight. Further, the etching temperature and time may be appropriately adjusted according to the shape of the etching site, the etching depth, etc., but it is usually sufficient that the temperature is 20 to 90 ° C. and about 1 to 30 minutes. When the energization method is adopted, either direct current or alternating current may be used. In this case, the current density is generally about 5 to 10000 mA / cm ² .

  Etching treatment includes etching for providing through holes, through grooves, through bands, etc. in the metal foil, etching for expanding the surface area of the metal foil, etching for adjusting the surface roughness of the metal foil surface, etc. Either type of etching process can be applied.

  In the present invention, after the etching process, the resist layer is stripped in the solution. The peeling method itself may follow a known method. The time required for stripping can be appropriately determined according to the temperature of the etching solution, the composition or thickness of the resist layer, and the like.

  The etched metal foil obtained by the production method of the present invention is used in a wide range of fields, including the same applications as known etched foils. For example, it can be used for printed wiring, circuits such as contactless resonance tags / IC cards, electrodes for electrolytic capacitors, current collectors for secondary batteries / electric double layer capacitors, electromagnetic wave shields / electromagnetic wave absorbers, and the like.

  According to the present invention, since the resist layer is formed of a specific resist solution, the etching process and the resist layer peeling process can be performed with one kind of etching solution. As a result, 1) the process can be shortened as compared with the prior art, 2) the solution can be easily managed, and 3) less equipment than before can be obtained.

  In the above laminate, the etching time and the stripping time can be controlled by adjusting the composition of the resist layer.

  Furthermore, when the inorganic powder is contained in the resist layer, more excellent anti-blocking performance is exhibited.

  Examples and comparative examples are shown below to further clarify the features of the present invention. However, the scope of the present invention is not limited to these examples.

Examples and Comparative Examples Each resist ink shown in Table 1 was applied to one side of an aluminum foil (JIS: 1N99, soft material) of 150 mm × 150 mm × thickness 40 μm by a bar coater to prepare each sample. In this case, the area | region which apply | coated resist ink was made into the area | region of 100 mm x 100 mm center part of the said aluminum foil.

  The indications of the polyester-based resin and the isocyanate-based curing agent in Table 1 are as follows.

PS1: linear saturated polyester resin (molecular weight 15000-20000, glass transition point 67 ° C.)
PS2: linear saturated polyester resin (molecular weight 20000-25000, glass transition point 7 ° C.)
PS3: modified ether type polyester resin (molecular weight about 20000, glass transition point 22 ° C.)
Curing agent: adduct-type toluene diisocyanate (molecular weight 665)
Each resist ink used was adjusted with a mixed solvent (methyl ethyl ketone: toluene = 1: 1 (weight ratio)) such that the viscosity was about 20 seconds with Zahn Cup No. 4.

  Next, each sample was dried at 40 ° C. for 72 hours, and then immersed in a 10% by weight hydrochloric acid aqueous solution (75 ° C.), whereby the etching treatment and the stripping treatment were continuously performed in the same aqueous hydrochloric acid solution. After stripping, the sample was dried with warm air.

Test example 1
About each sample of an Example and a comparative example, it investigated about peeling time, blocking, and the resist effect. The results are shown in Table 1.

<Peeling time>
The time until the resist layer completely peeled was measured.

<Evaluation of blocking>
Each sample before etching is stacked so that the resist layers face each other, sandwiched between glass plates, held in a constant temperature room at 60 ° C. for 48 hours under a load of 500 g from above, and then subjected to a sensory test at room temperature. went. The evaluation contents in Table 1 are as follows.

5: Can be easily separated into two sheets with one hand 4: Can be separated into two sheets with one hand 3: Although difficult to separate with one hand, it can be easily separated into two sheets with both hands 2: Separated into two sheets with both hands Possible 1: Partial separation of the surface when trying to separate with both hands <Evaluation of resist effect>
The situation during etching and peeling treatment of each sample and the sample after peeling were visually observed and judged. The evaluation contents in Table 1 are as follows.

A: Stripped uniformly after a certain period of time, and the resist part is hardly etched B: Since the film is gradually peeled off, unevenness is caused and the resist part is partially etched C: Resin is broken and there is no resist effect, Etching up to unnecessary parts D: Peeling off too early and resist effect, etching up to unnecessary parts E: Not peeling

It is a figure (sectional drawing) which shows the one aspect | mode of the metal foil laminated body for an etching of this invention. It is a figure (sectional drawing) which shows the one aspect | mode of the metal foil laminated body for an etching of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Metal foil laminated body for etching 2 ... Metal foil 3a, 3b ... Resist layer 4 ... Resin film layer

Claims (7)

A resist layer made of a resist solution containing a saturated polyester resin and at least one polyester resin of the modified polyester resin and an isocyanate curing agent is formed on a part of the metal foil, and the resist layer can be peeled off in the etching solution. A metal foil laminate for etching. The metal foil laminate for etching according to claim 1, wherein the polyester resin is contained in an amount of 44 to 99.7% by weight based on the total amount of the polyester resin and the isocyanate curing agent. The metal foil laminate for etching according to claim 1 or 2, wherein the polyester resin has a molecular weight of 15,000 to 25,000. The glass transition point of the said polyester resin is 5-70 degreeC, The metal foil laminated body for an etching in any one of Claims 1-3. The metal foil laminate for etching according to any one of claims 1 to 4, wherein the isocyanate compound in the isocyanate curing agent has a molecular weight of 300 to 1,000. The metal foil laminate for etching according to any one of claims 1 to 5, which is used for performing etching of a metal foil and peeling treatment of a resist layer in one etching solution. 7. A printed wiring, a contactless resonance tag / IC card circuit, an electrode of an electrolytic capacitor, a current collector of a secondary battery / electric double layer capacitor, and an electromagnetic wave shield / electromagnetic wave absorber. The metal foil laminate for etching according to any one of the above.

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