JP5255612B2 - Pre-coated aluminum plate and manufacturing method thereof - Google Patents

Description

  The present invention relates to an intermediate plate used for manufacturing printed circuit boards, aluminum plates and aluminum alloy plates applied to outer plate materials and structural members such as household electrical appliances and automobile mounting parts, and has heat resistance on the surface of the aluminum plate. Further, the present invention relates to a precoated aluminum plate provided with a coating excellent in releasability and scratch resistance.

  Aluminum plates and aluminum alloy plates applied to outer plate materials and structural members such as household electrical appliances and automotive parts, etc. have corrosion resistance, favorable appearance and scratch resistance to retain them, and others that correspond to applications In order to impart the above characteristics to the surface, a pre-coated plate having a resin film formed on the surface may be applied. For example, in a part of a slot-in type disk drive, even if the label attached to the disk is peeled off and attached to the part, it is required to have releasability so that it can be easily peeled off.

  Moreover, there exists an intermediate board used for manufacture of a printed circuit board as another use of a precoat aluminum plate. Generally, a printed circuit board is manufactured as shown in FIG. The inner layer core material 5 on which the wiring pattern is formed is sandwiched between prepregs 7 in which a sheet-like fiber substrate made of glass fiber or the like is impregnated with a thermosetting resin such as an epoxy resin, and the copper foil 6 is overlapped on the prepreg 7. The laminated body 4 is pressed from both sides and heated at about 180 ° C. for a predetermined time (heating and pressing). By heating and pressing, the laminates 4 are bonded to each other by thermosetting the resin of the prepreg 7, and the printed circuit board 40 is obtained. In order to improve productivity, it is common to stack a plurality of laminated bodies 4 and perform heating and pressurization. As shown in FIG. 2A, a metal plate is used as a partition between the laminated bodies 4 and 4. An intermediate plate 10 is sandwiched. As the intermediate plate, an aluminum plate is preferable because of its high thermal conductivity, but the aluminum plate is likely to have wrinkles and irregularities on its surface. If wrinkles occur on the surface of the intermediate plate, the wrinkles are transferred to the printed circuit board by heating and pressurization, and the quality of the printed circuit board deteriorates. Therefore, the aluminum plate cannot be used repeatedly. However, from the viewpoint of cost reduction, an intermediate plate is developed in which a surface treatment is applied to an aluminum plate so that it can be used repeatedly to impart heat resistance, releasability, and the like.

  As such an intermediate plate, an aluminum plate having an anodized surface is known (for example, Patent Document 1). However, since the anodizing treatment is relatively expensive and inferior in productivity, a technique using a pre-coated aluminum plate in which a resin film is formed on the surface of the aluminum plate is disclosed (for example, Patent Documents 2 and 3).

Japanese Patent No. 3808406 JP 2001-225341 A Japanese Patent No. 3273363

  However, both the fluororesin film described in Patent Document 2 and the mixed resin film of epoxy resin and silicone resin described in Patent Document 3 are easily wrinkled, and the wrinkles of the resin film are transferred to the printed circuit board. For this reason, there has been a problem that it cannot sufficiently withstand repeated use as a coating on the intermediate plate. In particular, a silicone resin requires a baking process for a long time of 1 minute or more at a high temperature of about 300 ° C. when forming a film. If the baking is insufficient, a predetermined heat resistance cannot be obtained, and a pre-coated aluminum in a coil shape. Since problems such as blocking occur when the plate is wound up, productivity is inferior when manufactured by a coil coat method as compared with a general urethane resin or acrylic resin as a resin film.

  The present invention has been made in view of the above problems, and in particular, a precoated aluminum plate that can be repeatedly used at high temperatures as an intermediate plate used in the production of a printed circuit board and is excellent in releasability and scratch resistance. The purpose is to provide.

  As a result of intensive studies to solve the above problems, the present inventors have come up with the idea of optimizing the ratio of fluorine and silicon in the resin film.

That is, the precoated aluminum plate of the invention according to the present invention includes an aluminum plate and a resin film having a film thickness of 0.2 μm or more and 7 μm or less formed on one or both surfaces thereof, and the resin film includes silicon, fluorine, and carbon. The ratio of fluorine to the total mass of oxygen and nitrogen is 1 to 25%, the ratio of silicon is 1 to 50%, and the pencil hardness is 4H or more by scratch determination. Here, when the concentration (mass%) of each element of silicon, fluorine, carbon, oxygen, and nitrogen in the resin film is represented by [Si], [F], [C], [O], [N], The proportion of fluorine is represented by A in the following formula (1), and the proportion of silicon is represented by B in the following formula (2).
A = [F] / ([Si] + [F] + [C] + [O] + [N]) × 100 (1)
B = [Si] / ([Si] + [F] + [C] + [O] + [N]) × 100 (2)

  Thus, by forming a film made of a resin in which the F and Si concentrations are regulated, the copper foil on the surface of the printed circuit board after heat pressurization can withstand heat pressurization at a high temperature of 180 ° C. and has excellent releasability. Can be easily separated, and the film has sufficient hardness and is difficult to be wrinkled.

  Furthermore, it is preferable that Si concentration (mass%) is higher than F density (mass%) in the range from the outermost surface to the depth of 1/4 of the film thickness.

  By containing Si concentration higher than F concentration in the vicinity of the surface in this way, the coating surface becomes difficult to slip, and when used as an intermediate plate in the production of printed circuit boards, workability when laminating copper foil, prepreg, etc. is improved To do.

A method of manufacturing a pre-coated aluminum plate of the invention according to the present invention is a method for manufacturing the pre-coated aluminum plate, a coating step of coating a paint containing one or Si on both sides, F of A aluminum plate, wherein a baking step of forming a tree fat coating applied coating to be baked at 210 ° C. or higher 280 ° C. or less, and performs.

  In this way, by applying the paint and baking it, the paint is dried and cured to form a resin film. Further, by controlling the baking temperature within a predetermined range, a resin film that is sufficiently cured and excellent in releasability can be obtained.

  The pre-coated aluminum plate according to the present invention is excellent in heat resistance, releasability, and scratch resistance, and therefore can be applied to outer plate materials and structural members such as household electric products and automobile-mounted parts. It can be used repeatedly as an intermediate plate at the time of manufacture, contributing to the manufacturing cost and quality improvement of the printed circuit board. Moreover, according to the manufacturing method of the precoat aluminum plate which concerns on this invention, it can manufacture with sufficient productivity by application | coating and a baking process.

It is sectional drawing explaining the structure of the precoat aluminum plate which concerns on this invention. It is a side view explaining the manufacturing method of a printed circuit board.

  The pre-coated aluminum plate according to the present invention is cut into a desired size and shape, and is used as an intermediate plate for manufacturing printed circuit boards. It is a board | plate material for setting it as a structural member. Hereinafter, the form for implement | achieving the precoat aluminum plate which concerns on this invention is demonstrated.

[Pre-coated aluminum plate]
A precoated aluminum plate 10 according to the present invention is obtained by coating a hard film (resin film) 2 on the surface of an aluminum plate 1 made of aluminum or an aluminum alloy. In the precoated aluminum plate 10 of the present invention, the hard coating 2 may be one that covers both sides of the aluminum plate 1 as shown in FIG. 1 or one that covers one side (not shown). The precoated aluminum plate 10 has a structure corresponding to the usage pattern. For example, when used as an intermediate plate in the production of a printed circuit board (see FIG. 2), the hard coating 2 is coated on the surface facing (contacting) the copper foil 6. To be.
Below, each element which comprises the precoat aluminum plate which concerns on this invention is demonstrated.

(Aluminum plate)
The aluminum plate 1 is a base material for the pre-coated aluminum plate 10, and 1000 series industrial pure aluminum, 3000 series Al—Mn alloy, 5000 series Al—Mg alloy can be applied, and may be selected depending on the application. . In particular, when drawing or ironing is performed, A1050, A1100, A3003, and A3004 defined in JIS H4000 are recommended. Also, A5052 and A5182 are recommended for use in applications requiring high strength. There is no restriction | limiting in particular about tempering and board thickness, It can select according to a use and the objective.

The aluminum plate 1 is preferably subjected to a surface treatment on the surface, and a ground treatment layer (not shown) is formed between the aluminum plate 1 and the hard coating 2. By the base treatment layer, the adhesion between the aluminum plate 1 and the hard coating 2 is improved, and the corrosion resistance of the aluminum plate 1 is improved. As the ground treatment layer, a film containing at least one of conventionally known Cr, Zr, and Ti can be applied. For example, a phosphate chromate film, a chromate chromate film, a zirconium phosphate film, a zirconium oxide film, a titanium phosphate film, a coating type chromate film, a coating type zirconium film, and the like can be used as appropriate. Moreover, you may make these films | membranes contain an organic component as needed. From the viewpoint of environmental consideration in recent years, it is desirable to use a phosphate chromate film that does not contain hexavalent chromium, a zirconium phosphate film, a zirconium oxide film, a titanium phosphate film, a coating-type zirconium film, or the like. As a guideline, the thickness of the ground treatment layer is desirably about 10 to 50 mg / m ^{2 in} terms of the amount of Cr, Zr, Ti deposited on the aluminum plate 1 (in terms of Cr, Zr, Ti). When the adhesion amount is less than 10 mg / m ² , the entire surface of the aluminum plate 1 cannot be uniformly coated, and the effect cannot be obtained sufficiently. On the other hand, when the adhesion amount exceeds 50 mg / m ² , cracks are likely to occur in the base treatment layer itself. The Cr, Zr, Ti converted value can be measured relatively easily and quantitatively by, for example, the fluorescent X-ray method. Therefore, quality control of the aluminum plate 1 can be performed without impeding productivity.

(Hard coating)
The hard coating 2 is provided for imparting heat resistance in the production of a printed circuit board and releasability from the copper foil, as well as scratch resistance due to its hardness. The hard coating 2 is made of a resin containing silicon (Si) and fluorine (F), specifically a fluorine resin bonded with silicon, and a mixed resin coating as will be described later is applied to the aluminum plate 1 for baking treatment. It is obtained by doing. The hard coating 2 approximates the ratio (%) of F and Si to the total mass of Si, F, carbon (C), oxygen (O), and nitrogen (N), and the concentration (% by mass) of F and Si. As an expressive representation, we will regulate as follows.

(F: 1-25%, Si: 1-50%)
If the ratios of F and Si are each less than 1%, the releasability of the hard coating 2 cannot be obtained. Furthermore, when the proportion of Si is less than 1%, the hardness of the hard coating 2 is insufficient. On the other hand, when the proportion of F exceeds 25% and the proportion of Si exceeds 50%, the adhesion of the hard coating 2 to the aluminum plate 1 decreases, and the resin primer layer between the aluminum plate 1 and the hard coating 2 If a measure such as forming an adhesive layer or the like is not taken, strong bonding cannot be performed.

The ratio of F and Si in the hard coating 2 formed on the surface of the precoated aluminum plate 10 can be obtained by measuring by, for example, an X-ray photoelectron spectroscopy (ESCA) method. When measuring from the surface of the pre-coated aluminum plate 10 on which the hard coating 2 is formed to the depth of the thickness of the hard coating 2, the components of the hard coating 2 such as Si and the component Al of the aluminum plate 1 or further aluminum alloy Additive elements are detected. Examples of the element detected as a component of the hard coating 2 include Si, F, and C generally contained in a resin, or further O, N. A value (unit: mass%) obtained by measuring the atomic ratio (atomic%) of these Si, F, C, O, and N and converting it to mass concentration (hereinafter, concentration) is [Si], [F], [C]. , [O], and [N], the F ratio can be calculated as A in the following formula (1), and the Si ratio can be calculated as B in the following formula (2). The ratio of F and Si can be approximated to the F and Si concentration of the hard film 2 when Si, F, C, O, and N are regarded as all components in the hard film 2.
A = [F] / ([Si] + [F] + [C] + [O] + [N]) × 100 (1)
B = [Si] / ([Si] + [F] + [C] + [O] + [N]) × 100 (2)

  Further, the hard coating 2 preferably has a Si concentration higher than the F concentration in the range from the outermost surface (the surface of the precoated aluminum plate 10) to a depth of 1/4 of the film thickness. Since the fluororesin has a high lubricity, when the F concentration of the hard coating 2 is higher than the Si concentration, the properties of the fluororesin become stronger and the lubricity becomes higher, and the lubricity is imparted to the surface of the precoated aluminum plate 10. When such a pre-coated aluminum plate 10 is used as the intermediate plate 10 in the production of a printed circuit board (see FIG. 2), the intermediate plate 10 easily slips during the stacking operation, and the stacked body 4 is likely to be displaced, resulting in a decrease in workability. By making the Si concentration higher than the F concentration, the surface of the precoated aluminum plate 10 becomes appropriate lubricity, and workability is improved in the production of the printed circuit board. Since the lubricity is a property on the surface, the lubricity of the hard coating 2 directly depends on the magnitude relationship between the Si and F concentrations in the vicinity of the surface, that is, in the range from the outermost surface to a depth of 1/4 of the film thickness. To do. In order to compare the Si and F concentrations in the vicinity of the surface of the hard coating 2, the ESCA method is used to detect Si and F from the surface of the precoated aluminum plate 10 to a depth of 1/4 of the thickness of the hard coating 2. Then, the atomic ratio may be measured and converted into mass concentration for comparison. It should be noted that the Si and F concentrations of the hard coating 2 have no noticeable bias in the distribution in the depth (film thickness) direction, and the magnitude relationship between the Si and F concentrations hardly changes depending on the depth. You may compare by the density | concentration [Si] and [F] measured for the ratio of Si, F in the whole hard film 2, or its calculation.

(Hardness: 4H or more by scratch determination of pencil hardness)
The hardness of the hard coating 2 is determined to be 4H or more by scratch determination by measuring the pencil hardness according to JIS K5600-5-4. By setting the hardness to this value, excellent releasability is exhibited. When the hardness is less than 4H, the copper foil is pushed into the hard coating 2 by heating and pressurization in the production of the printed circuit board, so that the copper foil and the hard coating 2 are easily bonded and the releasability is lowered.

(Film thickness: 0.2 μm to 7 μm)
The film thickness of the hard coating 2 is not less than 0.2 μm and not more than 7 μm. If the film thickness is less than 0.2 μm, the effect of the hard coating 2 cannot be sufficiently obtained in the precoated aluminum plate 10. On the other hand, even if the film thickness exceeds 7 μm, it is difficult to further improve the effect, and the cost of the material of the hard coating 2 increases. Moreover, since the hard film 2 can be continuously formed on the coiled aluminum plate 1 by using a roll coater by setting the film thickness within the above range, it is excellent in productivity and desirable in terms of cost. When the film thickness exceeds 7 μm, the liftability of the paint by the pick-up roll of the roll coater is insufficient and the variation in film thickness becomes remarkably large. On the contrary, if the film thickness is less than 0.2 μm, it is necessary to increase the pressure between the pickup roll and the applicator roll, and the roll is likely to be worn.

  The mixed resin paint for forming the hard coating 2 is obtained by adding a silicon compound, a silicone resin, or a silica resin to a fluorine resin material. The mixed resin paint can be continuously coated with a roll coater from the viewpoint of productivity and cost of the pre-coated aluminum plate 10 and cured by a short baking process of about 20 to 60 seconds in a baking furnace. Material is desirable. As such a material, fluororesin materials include PTFE (polytetrafluoroethylene), PVDF (polyvinylidene fluoride), PVF (polyvinyl fluoride), PFA (perfluoroalkoxy fluororesin), FEP (tetrafluoroethylene, Hexafluoropropylene copolymer), ETFE (ethylene / tetrafluoroethylene copolymer), ECTFE (ethylene / chlorotrifluoroethylene copolymer), acrylate-containing fluororesin, and the like. Examples of the silicone resin include silicone resins such as methyl silicone resin, phenyl silicone resin, and acrylate-containing silicone resin, and examples of the silicon compound include silicates such as silica, aluminosilicate, and borosilicate. Alternatively, a resin material forming a silicon-containing fluororesin, an acrylate-containing fluororesin / silicone resin copolymer, or the like may be applied.

  The hard coating 2 is a resin containing Si and F described above, but may contain other components as necessary in addition to these. For example, one or more lubricants such as palm oil, carnauba wax, polyethylene wax, and microcrystalline wax may be included in order to further improve press moldability. Furthermore, the hard coating 2 is a commonly used pigment, pigment dispersant, fluidity modifier, leveling agent, anti-waxing agent, in order to ensure the paintability of paint and general performance as a pre-coated metal plate. It may contain a preservative, a stabilizer and the like.

[Production method of pre-coated aluminum plate]
Next, the manufacturing method of a precoat aluminum plate is demonstrated. The method for producing a pre-coated aluminum plate according to the present invention includes a coating step in which a coating containing Si and F is applied to one or both sides of an aluminum plate 1, and a hard coating by baking the applied coating at 210 ° C to 280 ° C. And a baking step for forming a film (resin film) 2.

(Coating process)
The coating can be applied by any method such as brush coating, roll coater, curtain flow coater, roller curtain coater, electrostatic coating machine, blade coater, die coater, etc. However, a simple roll coater is preferable. In addition, the transport speed of the aluminum plate 1, the rotational direction and rotational speed of the roll coater, etc. are taken into consideration so that the hard coating 2 having a desired thickness in the range of 0.2 to 7 μm is formed on the surface of the aluminum plate 1. To adjust the coating amount as appropriate.

  You may perform the degreasing process of degreasing the surface of the aluminum plate 1 before performing an application | coating process. For example, an aqueous alkali solution is sprayed on the surface of the aluminum plate 1 and then washed with water.

  Furthermore, you may perform the base treatment process which forms a base treatment layer in the surface of the aluminum plate 1 before performing an application | coating process. For example, a phosphoric acid chromate treatment is performed on the aluminum plate 1 after the degreasing step to form a phosphoric acid chromate film.

(Baking process)
The aluminum plate 1 coated with the paint is baked at 210 ° C. or higher and 280 ° C. or lower to cure the paint. The baking temperature is the highest temperature reached by the aluminum plate 1. When the baking temperature is less than 210 ° C., the coating is not sufficiently cured, and the hardness of the hard coating 2 is insufficient. When the baking temperature exceeds 280 ° C., the paint starts to decompose, so that the hardness of the hard coating 2 decreases. The baking time is preferably 20 to 60 seconds. If the baking treatment time is less than 20 seconds, the baking may be insufficient. On the other hand, even if the baking treatment is performed for more than 60 seconds, no further curing occurs and productivity per hour decreases. The baking treatment can be performed using a hot air furnace, an induction heating furnace, a near infrared furnace, a far infrared furnace, an energy beam curing furnace, or the like.

  As mentioned above, although the form for implementing this invention has been described, the Example which confirmed the effect of this invention is described concretely compared with the comparative example which does not satisfy | fill the requirements of this invention below. In addition, this invention is not limited to this Example.

[Production of test materials]
(Pretreatment of aluminum plate)
As the aluminum plate 1, a JIS 5182H18 material having a thickness of 0.5 mm was applied. The aluminum plate was degreased with an alkaline aqueous solution and then subjected to a phosphoric acid chromate treatment to form a phosphoric acid chromate film of 20 mg / m ^{2 in} terms of Cr on both sides.

(Hard film formation)
A silicon-containing fluororesin paint having a different Si content was applied to one side of the aluminum plate after the base treatment. The silicon-containing fluororesin coating is Si-containing so that F: 0.1 to 10% by mass and Si: 0.1 to 20% by mass are measured by ICP (inductively coupled plasma) emission spectroscopy. The amount was adjusted. The test material No. 14-18 applied the paint shown in the remarks column of Table 1. Next, a baking treatment was performed at the baking temperature shown in Table 1 (the highest temperature reached by the aluminum plate) to prepare a precoated aluminum plate specimen. The heating method of the aluminum plate was a continuous baking method in which the aluminum plate coated with the paint moved from the entrance to the exit of the furnace, and the time for the aluminum plate to pass through the furnace was set as the heating time, which was adjusted to 30 seconds. Moreover, the heat label was affixed on the aluminum plate and the highest temperature reached of the aluminum plate was measured.

  About the obtained test material, the film thickness of the film was measured using an eddy current film thickness meter and shown in Table 1. In addition, an X-ray photoelectron spectroscopy (ESCA) apparatus (manufactured by Shimadzu Corporation) was used to measure from the coating surface of the test material to a depth corresponding to the thickness of the coating, and Si, F, C, O, N and Al were detected. Among these, the atomic ratio of Si, F, C, O, and N was measured, and the ratio (%) of F and Si was calculated from the formulas (1) and (2). The obtained F and Si ratios are shown in Table 1 as F and Si concentrations (mass%) of the film.

(Hardness of hard coating)
The pencil hardness was measured by scratch determination according to JIS K5600-5-4. The measurement results are shown in Table 1.

[Evaluation]
(Heating and pressing test)
A heating and pressing test simulating heating and pressing when a precoated aluminum plate was used as an intermediate plate in the production of a printed circuit board was performed. The copper foil was laminated on the surface of the test material with the glossy surface facing each other, heated at 180 ° C. for 90 minutes in a state of being pressurized at 30 kg / cm ² from both sides, and then the copper foil was separated from the test material. . The test which piles up copper foil again and heat-presses similarly was done 10 times about the same test material. After the first and tenth heating and pressurization, the releasability and the scratch resistance were evaluated, respectively.

(Releasability)
If the copper foil is easily separated from the surface of the test material (coating) after heating and pressing, it is “◯” as a pass, and those that cannot be separated unless the surface of the coating and the copper foil are bonded to each other are used as “bad” Is shown in Table 1.

(Scratch resistance)
The surface of the copper foil separated from the test material after heating and pressing was visually observed, and those with wrinkles and deformations were indicated as “x” as defective and those with no wrinkles or deformation as “O” as acceptable. It is shown in 1.

(blocking)
The two specimens were heated for 1 minute at 90 ° C. with the coatings facing each other, and then the specimens were separated one by one. Samples that can be easily separated are indicated by “◯” as “No blocking” (passed), and those that cannot be separated unless the coatings are adhered to each other to apply blocking, and “x” are indicated as “x” in Table 1. .

  As shown in Table 1, the test material No. In Nos. 1 to 12, since the Si, F concentration, baking treatment, and film thickness of the film all satisfied the scope of the present invention, a film with sufficient hardness was obtained, and the mold release and scratch resistance were good. No blocking occurred. In particular, specimen no. Even when the film thickness was reduced to 0.2 μm as in No. 4, release properties and scratch resistance were obtained in 10 heating and pressing tests. In addition, through the preparation and evaluation of the test materials, the paintability and corrosion resistance have no practical problems.

  On the other hand, the test material No. Nos. 13 to 18 are comparative examples in which the components of the film are outside the scope of the present invention. Specimen No. No. 14 is provided with a silicone resin film containing no F, and the baking temperature is low as a silicone resin. Especially, the film is insufficiently hard and has a mold release property and wrinkle resistance in a single heating and pressing test. It was inferior in properties and was unsuitable as an intermediate plate for producing printed circuit boards, and further caused blocking and unsuitable as a pre-coated plate. Similarly, the specimen No. provided with a film containing no F was used. 18 is a comparative example in which a mixed film of an epoxy resin and a silicone resin was formed at a baking temperature of 290 ° C. in the same manner as the film disclosed in Patent Document 3. Although it was higher than 14, it was inadequate, and in 10 heat-press tests, mold release and scratch resistance were not obtained. On the other hand, the test material No. Similarly, the fluororesin film containing 15 Si did not have sufficient hardness, and the mold release property and scratch resistance were not obtained in 10 heating and pressing tests.

  Specimen No. No. 17, as a result of forming a film with an epoxy paint that does not contain both Si and F, the hardness of the film is insufficient, and it is inferior in releasability and scratch resistance in a single heating and pressing test. It was unsuitable as an intermediate plate for the production of

  On the other hand, the test material No. The resin film with an excessive amount of 13 F cannot be directly bonded to the aluminum plate due to a decrease in adhesion, and it is necessary to provide a resin primer layer. In addition, scratch resistance was not obtained. Specimen No. Resin film with excess Si formed with 16 silica-based paint can be releasable and scratch-resistant, but cannot be directly bonded to the aluminum plate due to reduced adhesion and resin primer layer Therefore, the pre-coated board was inferior in productivity.

  Specimen No. Nos. 19 to 21 are comparative examples in which the components of the film are within the range of the present invention but the baking temperature is out of the range. Specimen No. Nos. 20 and 21 had a low baking temperature, the coating was not sufficiently cured, and the hardness of the film was insufficient. In particular, the test material No. with the lowest baking temperature. No. 21 was inferior in releasability and wrinkle resistance in one heating and pressurizing test, was unsuitable as an intermediate plate for producing a printed circuit board, further caused blocking, and unsuitable as a precoat plate. On the other hand, the test material No. No. 19 has a high baking temperature, and the coating started to decompose during the baking process, so that the hardness of the formed film became insufficient.

  Specimen No. Nos. 22 and 23 are comparative examples in which the film components and the baking temperature are within the range of the present invention, but the film thickness is out of the range. Specimen No. No. 22 was insufficient in film thickness, and it was not possible to obtain scratch resistance in 10 heat and pressure tests. On the other hand, the test material No. In No. 23, there was no problem in the releasability and scratch resistance, but by forming an excessively thick film, the film thickness varied and the appearance was poor.

  Sample No. 1 in the scope of the present invention in Example 1 was used. About 1, 2, 4-9, the influence on the lubricity by the magnitude relationship of the density | concentration of Si and F in a hard film was evaluated.

  In the measurement of the concentration of Si and F in the film in Example 1, the atomic ratio of Si and F in the region limited to the depth of 1/4 of the film thickness of the film from the surface of the test material (the surface layer of the film) It was measured. None of the test materials were significantly different from the atomic ratio of Si and F in the entire film, and the Si and F concentrations (mass%) could be regarded as equivalent. Table 2 shows a comparison of Si and F concentrations (% by mass). Furthermore, the Si, F concentration, film thickness, and hardness of the film measured in Example 1 are also shown in Table 2.

[Evaluation]
(Lubricity)
As an evaluation of the lubricity of the surface of the specimen (film surface), the friction coefficient was measured by the Bowden method (load 200 g). The results are shown in Table 2.

  As shown in Table 2, in the surface layer of the film, the test material No. 1, 2, 4 to 6 had a friction coefficient of 0.3 to 0.5, and their lubricity was suppressed to some extent, so that they became precoated aluminum plates more suitable as intermediate plates for producing printed circuit boards. On the other hand, test material No. with F concentration higher than Si concentration. In Nos. 7 to 9, the coefficient of friction was as small as 0.1 or less, and as an intermediate plate for producing a printed circuit board, a tendency of high lubricity was observed.

10 Pre-coated aluminum plate, intermediate plate 1 Aluminum plate 2 Hard coating (resin coating)

Claims (3)

A pre-coated aluminum plate comprising an aluminum plate and a resin film having a film thickness of 0.2 μm or more and 7 μm or less formed on one or both sides thereof,
In the resin film, the proportion of fluorine represented by A in the following formula (1) is 1 to 25% with respect to the total mass of silicon, fluorine, carbon, oxygen, and nitrogen, and represented by B in the following formula (2). A pre-coated aluminum plate, wherein the ratio of silicon to be formed is 1 to 50%, and the pencil hardness is 4H or more by scratch determination.
A = [F] / ([Si] + [F] + [C] + [O] + [N]) × 100 (1)
B = [Si] / ([Si] + [F] + [C] + [O] + [N]) × 100 (2)
[Si], [F], [C], [O], and [N] represent the concentration (mass%) of each element of silicon, fluorine, carbon, oxygen, and nitrogen in the resin film.   2. The resin film according to claim 1, wherein the resin film has a silicon concentration (mass%) higher than a fluorine concentration (mass%) in a range from the outermost surface to a depth of ¼ of the film thickness. Pre-coated aluminum plate. It is a manufacturing method of the precoat aluminum plate according to claim 1 or 2 ,
Si on one side or both sides of A aluminum plate, a coating step of coating a paint containing F,
The applied coating was baked at 210 ° C. or higher 280 ° C. or less, the production method of the precoated aluminum plates to a baking step of forming a resin film, and performing.

Images