JP4451911B2 - Method for producing resin-coated aluminum alloy plate - Google Patents

Description

The present invention relates to a method for producing a resin-coated aluminum alloy plate used for a case of a hard disk drive (hereinafter abbreviated as HDD).

Resin-coated aluminum alloy plates are used for HDD cases, and the main required performances are formability, contamination, and outgassing. The mechanism for accessing data inside the HDD is very precise, and even minute contaminants can be a problem.
Contamination is the amount of contaminants generated from a case molded during cleaning after press molding. When the amount of contaminants is large, the HDD mechanism may be adversely affected by the contaminants reattached to the inner surface of the case.

  Outgassing is the amount of gas generated from the resin layer of the case when the HDD is actually used, due to the temperature rise of the equipment. From the viewpoint of formability, it is better to coat the resin layer on both sides of the aluminum alloy plate. However, when the resin layer is coated on both surfaces of the aluminum alloy plate, the resin layer also exists on the inner surface of the case, and the outgas from this resin layer may adversely affect the internal mechanism of the HDD. This is particularly noticeable in HDDs having a small internal volume of 2.5 inches or less.

  Patent Document 1 is characterized in that an organic resin film having a friction coefficient of 0.3 or less and a surface roughness Ra of 1.0 to 30 μm is formed on one surface of an aluminum alloy base plate to a thickness of 6 μm or more. An aluminum alloy plate for HDD cases has been proposed, and addition of wax has been proposed as a method for improving the formability by reducing the coefficient of friction.

  In Patent Document 2, a resin film is coated on the surface of a base metal plate, and a solid lubricant is fixed on the film. The solid lubricant has a protrusion height from the resin film surface of 0. 0. A resin-coated metal plate excellent in mold galling resistance and corrosion resistance, characterized in that the area ratio in a plan view of the solid lubricant is 01 to 1.5 μm and less than 1 to 15% is proposed. .

Japanese Patent No. 3234541 Japanese Patent Laid-Open No. 10-052881

With the recent increase in density and miniaturization of HDDs, demands for contamination and outgassing have become stricter. Under such circumstances, there are cases where these resin-coated aluminum alloy plates and metal plate materials do not provide sufficient contamination and outgassing properties.
In the technology disclosed in Patent Document 1, when the press oil is washed after molding on the case, the wax and resin beads in the resin layer fall into the cleaning liquid and reattach to the inner surface of the case, affecting the internal mechanism of the HDD. There was a case. The technique disclosed in Patent Document 1 is a technique for forming a resin layer only on one side, but if the moldability is insufficient, it is effective to form this film on both sides. However, if formed on both sides, depending on the cured state of the resin layer and the additives contained, outgas may be generated from the resin layer on the inner surface of the case, which may affect the internal mechanism of the HDD.

  In the technique disclosed in Patent Document 2, in order to prevent the solid lubricant on the surface of the resin layer from falling off, the protrusion height and area ratio of the solid lubricant are defined. However, when it is used for an HDD case, the contamination may be insufficient even with this rule, and depending on the cured state of the resin layer and the additive contained, there may be a problem with the outgassing property.

In view of the above problems, the present invention provides a method for producing a resin-coated aluminum alloy plate having good contamination and outgassing properties while ensuring sufficient formability, corresponding to high density and miniaturization of HDDs. The purpose is to do.

In the method for producing a resin-coated aluminum alloy plate of the present invention, a granular lubricant having an average particle size of not more than twice the thickness of a resin layer formed by coating is 0.1% by weight or more and 5% by weight based on the solid content. % Or less of the paint added is baked so that (T2-T1) is 20 seconds or less.
T1: Time for the baking temperature to reach a temperature 6 degrees higher than the melting point of the granular lubricant T2: Time for the baking temperature to reach a temperature 100 degrees lower than the final curing temperature

The method for producing a resin-coated aluminum alloy plate of the present invention is characterized in that a paint containing 0.1% by weight or more and 10% by weight or less of an S compound is baked so that T2 is 10 seconds or more with respect to the solid content. And
T2: Time for the baking temperature to reach a temperature 100 degrees lower than the final curing temperature

Furthermore, the method for producing a resin-coated aluminum alloy plate of the present invention is characterized in that a paint containing 0.1% by weight or more and 10% by weight or less of Sn compound is baked so that T2 is 10 seconds or more with respect to the solid content. And
T2: Time for the baking temperature to reach a temperature 100 degrees lower than the final curing temperature

In addition the production method of the resin-coated aluminum alloy sheet of the present invention, the baking paint containing 0.1% by weight to 10% by weight of Si compound on the solid content, so T2 is equal to or less than 30 seconds Features.
T2: Time for the baking temperature to reach a temperature 100 degrees lower than the final curing temperature

A hard disk drive case using the resin-coated aluminum alloy plate of the present invention and a hard disk drive using a hard disk drive case using the resin-coated aluminum alloy plate of the present invention for the case are suitable.

According to the method for producing a resin-coated aluminum alloy plate of the present invention, it is possible to realize good contamination and outgassing properties while ensuring sufficient formability in response to high density and miniaturization of HDDs.

Hereinafter, the resin-coated aluminum alloy plate obtained by carrying out the method for producing a resin-coated aluminum alloy plate of the present invention will be described in detail.
(1) Examination of surface lubricant Since HDD has very precise mechanical parts for data access, there is a very strict requirement for the adhesion of contaminants to the inner surface of the case.
On the other hand, in the case of a resin-coated aluminum alloy plate, a lubricant is added to the resin layer in order to improve its formability, and this granular lubricant on the surface improves the lubricity of the resin layer surface. To improve formability. Further, the granular lubricant to be added tends to have a higher formability improvement effect when the particle size is larger and when the addition amount is larger.

  At the same time, however, the granular lubricant on the surface may fall off during cleaning after pressing and become a contaminant. When the cleaning fluid is contaminated by the dropped granular lubricant, the contaminant reattaches to the resin-coated aluminum alloy plate. When this is used as a case for storing a hard disk drive, the contaminant attached to the inner surface of the case The possibility of adverse effects when the internal mechanism of the HDD functions cannot be denied.

  A particulate lubricant is added to the paint to cause the particulate lubricant to be present in the resin layer on the surface of the aluminum alloy. Each granular lubricant is considered to have a shape having the smallest area of the interface between the granular lubricant and the resin layer or air, that is, a spherical shape, and exists in various depths and various sizes in the resin layer.

As shown in FIG. 1, when the granular lubricant 1 is added to the paint and the granular lubricant 1 is present in the resin layer 3 on the surface of the aluminum alloy layer 2, the granular lubricant 1 distributed in the resin layer 3 is 2 t. (Twice the thickness of the resin layer)> diameter and a straight line H drawn horizontally through the center of the sphere in the horizontal direction of the granular lubricant 1 with respect to a straight line h drawn horizontally from the outermost surface 3a of the resin layer 3 However, if the granular lubricant 1a is on the inner side (the aluminum alloy layer 2 side), it is firmly held by the resin layer 3 and hardly falls off. On the other hand, the granular lubricant 1c where 2t <diameter and H is on the outer side (air layer 4 side) than h is not held by the resin layer 3 and easily drops off.
That is, the granular lubricant 1c having a diameter exceeding twice the resin layer thickness (t) is likely to fall off at any depth, and if the granular lubricant 1c exceeding twice is controlled, a resin having excellent contamination properties Layer 3 can be obtained.

For this purpose, it is conceivable to control the particle size when adding the granular lubricant to the paint. However, since the melting point of the lubricant is low compared to the temperature at which the resin is cured, it becomes liquid during baking of the paint and spreads on the surface as the paint convects, and it can bind to other lubricants in the paint. Some of them grow greatly, and it is thought that they do not exist in the resin layer as they are in the paint. Therefore, regarding the contamination of the granular lubricant on the surface, it is necessary to examine the granular lubricant that exists after the resin layer is formed.

Here, the granular lubricant in the resin layer is investigated as follows. That is, the resin-coated aluminum alloy plate is ultrasonically cleaned using MEK at room temperature for 10 minutes, and a secondary electron image of the ultrasonically cleaned resin-coated aluminum alloy plate is observed with an SEM (scanning electron microscope). By ultrasonic cleaning with MEK, the resin layer slightly melts and swells and softens, so that the granular lubricant is dropped, and holes formed by the dropping are observed. What can be seen as a hole when observed without an inclination by SEM at an acceleration voltage of 5 to 10 kV (when the contrast is increased, the periphery of the hole becomes white due to the edge effect, and it is black and can be clearly recognized as a hole. ) Is a hole where the granular lubricant has dropped. As a result, the presence state of the granular lubricant on the surface of the resin layer can be known.

By the way, the diameter of the hole formed by dropping the granular lubricant is equal to or smaller than the diameter of the granular lubricant existing there. In other words, if the straight line drawn in the horizontal direction from the center of the granular lubricant and the resin layer surface match, the diameter of the hole and the diameter of the granular lubricant are the same, and if they do not match, there is a granular lubricant. The diameter of the granular lubricant is larger than the diameter of the hole.
Therefore, by measuring the number of holes observed by the above method, the number of granular lubricants having a diameter equal to or larger than the diameter of the holes can be estimated.

Various lubricants were added to the resin layers having different thicknesses to produce resin-coated aluminum alloy plates, and the number of holes having a diameter equal to or greater than the resin layer thickness was measured by the above method. This resin-coated aluminum alloy sheet was press-molded, and the number of contaminants in the cleaning liquid after cleaning the press oil was investigated. As a result of investigating the relationship between the number of holes observed on the surface of the resin layer and the contamination property, it was confirmed that there was a correlation. Specifically, the number of holes having a diameter of at least twice the thickness of the resin layer, which is formed on the surface of the resin layer by dropping the granular lubricant by ultrasonic cleaning with MEK, is 100 per square mm or less. In this way, it was found that the contaminants in the cleaning liquid can be reduced sufficiently by controlling the granular lubricant. Preferably, it is 50 pieces / square mm.
On the other hand, the number of holes whose diameter is less than twice the resin layer thickness is related to the number of relatively small granular lubricants, and if the number of holes is extremely small, moldability may be insufficient. Specifically, the number of holes having a diameter less than twice the resin layer thickness is preferably 10 or more.

Carnauba wax, polyethylene wax, microwax, lanolin, etc. are added in an amount of 0.1 wt% to 5 wt% with respect to the solid content of the paint so that the average particle size is less than twice the resin layer thickness. Baking is performed so that the resin layer is dispersed as it is.
The particle size of the granular lubricant is increased because the individual lubricants are reduced so that the interfacial energy between the lubricant and the main resin of the resin layer decreases if the granular lubricant is in a molten state for too long. The particle size grows due to bonding. This is because if the volume is the same, the larger the particle size, the smaller the surface area and the lower the interfacial energy.

Therefore, it is possible to obtain a resin-coated aluminum alloy sheet having sufficient formability and excellent contamination by specifying the time until the main resin cures to some extent beyond the melting point of the lubricant during baking. it can.
Specifically, when T1 is the time for the baking temperature to reach a temperature 6 degrees higher than the melting point of the granular lubricant, and T2 is the time for the baking temperature to reach a temperature 100 degrees lower than the final curing temperature. The baking process of the lubricant is preferably performed so that (T2-T1) is 2 seconds or more and 20 seconds or less. If it is less than 2 seconds, the paint may boil and defects may occur in the resin layer, and the moldability may deteriorate. If it exceeds 20 seconds, the diameter of the resin layer surface after the MEK cleaning will be more than twice the resin layer thickness. The number of holes (pieces / square mm) may exceed 100 pieces / square mm.

(2) Study for reducing the amount of outgas The outgas that adversely affects the internal mechanism of the HDD is a gas generated when the resin layer is heated by heat generated by the HDD itself or the base of the computer.
When using a resin-coated aluminum alloy plate for the HDD case, the gas source is
(I) A monomer or residual solvent present in a low molecular weight without crosslinking in the resin layer.
This (i) becomes a gas source because, when the HDD is actually used, when the heat is generated by the heat generated by the integrated circuit, the monomers and additives sublimate or the solvent evaporates to become outgas. Presumed.

As another gas source,
(Ii) S (sulfur) compounds (such as sulfonic acid-based catalysts) or Sn (tin) compounds (such as organic Sn-based catalysts) or Si (silicon) compounds (silicone-based antifoaming agents, silicone-based lubricants, silicone-based antifouling agents) Additive (hydrophilic agent), silane coupling agent, etc.).
It is known that the gas source shown in (ii) has an adverse effect on the internal mechanism of the HDD even in a small amount.
The S compound or Sn compound shown in (ii) is widely used in commercial paints in order to cure the paint. If such a commercial paint is used, the development cost used for the resin-coated aluminum alloy plate for HDD cases can be reduced. However, in that case, it is necessary to paint so as not to generate outgas from the S compound or the Sn compound.

The outgas amount can be quantified by analyzing the gas generated when the resin-coated aluminum alloy plate is heated by GC / MS (gas chromatography / mass spectrometry). This gas can be quantified by an n-hexadecane conversion value in which the peak of the obtained total ion chromatogram is quantified using an n-hexadecane calibration curve. In addition, the quantification of the S compound, Sn compound, and Si compound is intended only for substances detected by GC / MS, and the quantification can be performed in terms of n-hexadecane.

(I) Method for reducing outgas generated from monomer and residual solvent present in low molecular weight without cross-linking in resin layer For monomer and residual solvent in (i), outgassing is reduced by sufficiently accelerating curing. can do. However, on the other hand, if curing proceeds too much, the elongation of the resin layer becomes small and sufficient moldability cannot be obtained. Although it is difficult to directly measure the amount of monomer and residual solvent in the resin layer, by measuring the MEK extraction rate, the degree of cure acceleration can be measured and indirect measurement can be performed.

  A paint layer is prepared using various paints, and a resin layer is formed by coating under different baking conditions. As a result of measuring the MEK extraction rate under boiling conditions, if the extraction rate is 40% or less, It was found that the HDD case material has sufficient outgassing properties. Preferably, it is 20% or less.

On the other hand, if the curing of the resin layer proceeds too much, the elongation of the resin layer becomes too small, and if the extraction rate is less than 5%, sufficient moldability cannot be obtained. Therefore, the extraction rate must be between 5% and 40%. Preferably they are 10% or more and 20% or less. In order to obtain a cured state having such an extraction rate by coating, the final curing temperature in baking should be examined .

(Ii) Method for reducing outgas generated from S compound, Sn compound, and Si compound S compound, Sn compound, and Si compound have a great adverse effect even in a very small amount. Therefore, when used for a HDD with a small case capacity of 2.5 inches or less. In some cases, examination of the extraction rate alone is not sufficient. Therefore, when using a resin coating material having a resin layer to which these compounds are added, it is preferable to define the S compound, Sn compound, and Si compound as follows.

As described above, commercially available paints may contain an S compound such as organic sulfonic acid or an Sn compound such as organic tin as a catalyst. Depending on the shape of the HDD case, a resin layer is formed on both sides in order to obtain sufficient moldability. In this case, the S compound or Sn compound may be generated as outgas from the resin layer on the inner surface of the case, which may adversely affect the precision parts inside the case.
Therefore, the S compound gas and Sn compound gas generated from the resin layer when heated at 200 ° C. for 30 minutes are 5 ppm (gas amount 5 μg / resin-coated aluminum alloy) in terms of n-hexadecane when the outgas is analyzed by GC / MS. (Plate 1g, the same applies hereinafter) The following is preferable. For that purpose, it is preferable to make the amount of S compound and Sn compound in the solid content of the paint 0.1% by weight or more and 10% by weight or less.
If it is less than 0.1% by weight, a sufficient effect as a catalyst cannot be obtained, and if it exceeds 10% by weight, it is difficult to reduce the S compound gas and Sn compound gas to 5 ppm or less even when baked by the following method. .

As the S compound, organic sulfonic acids such as dodecylbenzenesulfonic acid, dinonylnaphthalenedisulfonic acid, dinonylnaphthalenesulfonic acid, and paratoluenesulfonic acid are generally used.
As the Sn compound, tin octylate, dioctyltin oxide, monobutyltin trioctate and the like can be used.

  As a result of investigating the relationship between various addition amounts, baking conditions, and outgas amount, it was found that the S compound concentration and Sn compound concentration on the surface of the resin layer had a great influence on the outgas amount. That is, it was found that even if the concentration of the S compound and the Sn compound in the resin layer is the same, the outgas concentration can be lowered by reducing the surface concentration.

Specifically, the time required to enter the baking furnace after applying the paint to the aluminum alloy plate is set to 1 second or longer. By doing so, it is presumed that the concentration of the outermost surface decreases and the outgas amount decreases because the S compound and Sn compound have a relatively large specific gravity.
For example, when painting on a painting line with a roll coater, it is difficult to change the distance between the coater and the baking furnace, so the line speed is slowed down. However, this reduces productivity, so it is preferable to lengthen the time during which the paint flows during baking. Specifically, as shown in FIG. 2, when T2 is the time for the baking temperature to reach a temperature 100 degrees lower than the final curing temperature, T2 is preferably 10 seconds or longer and 40 seconds or shorter. If the time is less than 10 seconds, the surface concentration of the S compound may not be sufficiently lowered. If the time exceeds 40 seconds, the S compound in the vicinity of the surface may be insufficient and curing may not proceed sufficiently, and the moldability may be lowered.

As described above, commercially available paints may contain a silane coupling agent for improving adhesion, a Si compound such as a silicone resin as an antifoaming agent for improving stain resistance and lubricity.
Depending on the shape of the HDD case, a resin layer is formed on both sides in order to obtain sufficient moldability. In this case, the Si compound may be generated as outgas from the resin layer on the inner surface of the case, which may adversely affect the precision parts inside the case.
Accordingly, the Si compound gas generated from the resin layer when heated at 200 ° C. for 30 minutes is preferably 5 ppm or less in terms of n-hexadecane when the outgas is analyzed by GC-MS.

When adding Si compound, it is preferable to make it into 0.1 weight% or more and 10 weight% or less in coating-material solid content. If the amount is less than 0.1% by weight, the effect is insufficient. If the amount exceeds 10% by weight, it is difficult to reduce the Si compound gas to 5 ppm or less even if baking is performed by the following method. As examples of the silane coupling agent, 3-aminopropyltriethoxysilane, aminosilane, 3-ureidopropyltriethoxysilane, and the like can be used.

As a result of investigating the relationship between various addition amounts, baking conditions, and outgas amount, it was found that the Si compound concentration on the surface of the resin layer had a great influence on the outgas amount. In other words, it was found that even if the concentration of the Si compound in the resin layer is the same, the outgas concentration can be lowered by reducing the surface concentration. In this respect, since the Si compound has a relatively small surface energy, the Si compound on the surface of the resin layer will be more stable if it is allowed to flow for a long time before the paint is baked so that the surface energy of the resin layer is lowered and becomes more stable. Concentration increases.
Therefore, in order to prevent this, specifically, the time required to enter the baking furnace after applying the paint on the aluminum alloy plate is set to 5 seconds or less.
In this way, it is presumed that the Si compound concentration on the outermost surface of the resin layer decreases and the outgas amount decreases.

  For this purpose, it is difficult to change the distance between the coater and the baking furnace when painting on a coating line with a roll coater. Therefore, it is conceivable to increase the line speed and shorten the time to enter the baking furnace. However, if the line speed is too high, defects such as streaks and substrate exposure will occur in the resin layer. Therefore, in order to prevent the occurrence of the problem, it is preferable to shorten the time during which the paint flows during baking. Specifically, when the time for the baking temperature to reach a temperature lower by 100 degrees with respect to the final curing temperature is T2, T2 is preferably 10 seconds or longer and 30 seconds or shorter. If it is less than 10 seconds, the paint boils before curing, defects occur in the resin layer and moldability is reduced, and if it exceeds 30 seconds, the Si compound concentration on the surface may not be sufficiently reduced.

(3) Study of the main resin of the resin layer As the main resin constituting the resin layer, an epoxy resin or a polyester resin is desirable.
It is because it is excellent in moldability compared with other resins. As the epoxy resin, a glycidyl ether type such as bisphenol A type or bisphenol F type or a glycidyl ester type can be used.
As the curing agent, amino resins such as melamine formaldehyde resin, benzoguanamine resin and urea resin, phenol resins of novolac type and resol type, acrylic resins such as methyl methacrylate, isopropyl acrylate and n-butyl acrylate can be used.

As the polyester resin, polyols such as ethylene glycol and propylene glycol, fatty acids such as succinic acid, glutaric acid and adipic acid, and aromatic esters such as phthalic acid, isophthalic acid and terephthalic acid can be used.
As the curing agent, amino resins such as melamine formaldehyde resin, benzoguanamine resin and urea resin, and isocyanates such as tolylene diisocyanate, diphenylmethane isocyanate and xylylene diisocyanate can be used.

(4) Examination of aluminum alloy plate surface shape The center line average roughness (Ra) of the surface of the aluminum alloy plate to be used is preferably 0.1 μm or more and 0.5 μm or less.
If the thickness is less than 0.1 μm, when molding into a case having a severe shape, the adhesiveness of the resin layer may be insufficient and may peel during molding. On the other hand, if the thickness exceeds 0.5 μm, the resin layer may be broken at the time of molding, and the molding may not be possible due to insufficient lubrication.

(5) Study resin layer thickness of the resin layer thickness is preferable to be 0.1μm or more 22μm or less. This is because if the thickness is less than 0.1 μm, the resin layer is easily broken when stretched. This is because if the thickness exceeds 22 μm, the internal stress of the resin layer at the time of molding becomes too large, and the resin layer may peel off after molding. More preferably, it is 4 μm or more and 12 μm or less.

[Example 1]
Examples of the present invention will be described below.
JIS A5052-H34, a 0.75 mm-thick aluminum plate material was degreased with a commercially available alkaline degreasing solution as a coating base treatment, and then subjected to a chemical conversion treatment with a commercially available phosphoric acid chromate treating solution. Various paints shown in Tables 1 to 9 were baked on one surface of the aluminum plate to prepare samples. Non-crystalline polyester resin is used as the polyester resin, and 5 wt% of polyol-modified blocked tolylene diisocyanate is added to the solid content of the paint (polyester / isocyanate series), and 5 wt% of butylphenol is added as the curing agent. (Polyester / phenol) and 5 wt% of benzoguanamine (polyester / melamine) were used.

The epoxy resin is bisphenol A type epoxy resin, and the curing agent is 5% by weight of butylated urea resin added to the solid content of the paint (epoxy / urea), and 5% by weight of butylphenol (epoxy / phenol). System) and 5 wt% methacrylic acid (epoxy / acrylic system) were used.
A mixture of methyl methacrylate and methacrylic acid was used as the acrylic resin, and 5% of melamine resin was added to the solid content as the curing agent. The vinyl chloride type used was an organosol type. The lubricants and various compounds shown in Tables 1 to 9 were added to these paints.

These paints were applied using a baking furnace having three zones. The temperature of each zone was controlled, and T1 and T2 were changed as shown in Table 2, Table 5, and Table 8. As for T1, T2, and final hardening temperature, all measured the temperature of the aluminum plate. The coating material thus prepared was evaluated for film thickness, extraction rate, lubricant distribution on the surface of the resin layer, moldability, outgassing, and contamination.
(Film thickness)
The resin layer thickness was measured at five locations with an eddy current film thickness meter, and the average value was taken as the resin layer thickness.
(MEK extraction rate)
For the MEK extraction rate, a sample cut to a 100 mm square was used. After measuring the initial weight, it was immersed in boiling MEK for 1 hour and dried, and the weight was measured after immersion in MEK. Thereafter, the film was immersed in concentrated sulfuric acid for 5 minutes to remove the film, washed with water, dried, and measured for weight after removal. The MEK extraction rate was calculated from the following formula. (Average value of n5)
The lower layer MEK extraction rate was measured after the lower layer formation and before the upper layer formation, and the entire MEK extraction rate was measured after the lower layer and upper layer formation.

MEK extraction rate (%) = {(initial weight−weight after MEK immersion) / (initial weight−weight after film removal)} × 100

(Particulate lubricant distribution on the surface of the resin layer)
After the coating material was ultrasonically cleaned with MEK for 10 minutes at room temperature, the surface was observed with a SEM for secondary electron images, and the distribution of the holes where the granular lubricant was removed was investigated.

(Formability evaluation method)
Apply volatile press oil (kinematic viscosity 1.6 square mm / s) on both sides, and perform cylindrical deep drawing with a punch diameter of 33 mmφ and a wrinkle holding force of 300 kgf so that the resin layer is on the outer surface. The ratio was measured. The evaluation criteria are shown below. ○ If it is above, it can be used as an HDD case material.
A: Limit drawing ratio ≧ 2.5
A: 2.5> limit aperture ratio ≧ 2.1
○: 2.1> Limiting drawing ratio ≧ 1.9
Δ: 1.9> Limit drawing ratio

(Outgas)
Using a gas chromatograph with a mass spectrometer, the amount of organic gas generated upon heating the resin-coated aluminum alloy sheet of 100mm square 200 ° C. × 30 hours was determined by n-hexadecane conversion. The evaluation criteria are shown below (unit: ppm by weight of gas generated from 1 g of sample. 1 μg of gas / 1 g of sample = 1 ppm).
○ If it is above, it can be used as an HDD case material.
◎: 10 ppm> outgas amount ○: 100 ppm> outgas amount ≧ 10 ppm
Δ: Outgas amount ≧ 100 ppm

For the S compound, Sn compound, and Si compound, the outgas generated under the same heating conditions was quantitatively analyzed in terms of n hexadecane using a gas chromatograph having a mass spectrometer. The evaluation criteria are shown below (unit: ppm by weight of gas generated from 1 g of sample. 1 μg of gas / 1 g of sample = 1 ppm).
If it is more than ○, it can be used as an HDD case material, and if it is ◎, it can also be used for an HDD case with a small case volume of 2.5 inches or less.
A: 5 ppm> outgas amount ○: 10 ppm ≧ outgas amount ≧ 5 ppm
Δ: Outgas amount> 10 ppm

(Contamination)
Volatile press oil (kinematic viscosity 1.6 square mm / s) was applied to both sides, and square tube deep drawing with a width of 100 mm x length of 150 mm x depth of 15 mm was carried out so that the resin layer would be the outer surface. , Ultrasonic cleaning (10 minutes) with 1 liter of aqueous cleaning solution (5% non-ionic surfactant added), and another 1 liter aqueous cleaning solution (5% non-ionic surfactant) (Added) was subjected to ultrasonic cleaning (10 minutes).
The number of particles having a particle size of 0.5 μm or more contained in the cleaning liquid after the second cleaning was measured with a particle counter. Evaluation criteria are shown below (unit: number of particles per liter of MEK). ○ If it is above, it can be used as an HDD case material.
A: 500 / liter> number of particles ○: 1000 / liter> number of particles ≧ 500 / liter Δ: number of particles ≧ 1000 / liter

  Invention Example 2 to Invention Example 6 is that the material has a surface roughness Ra of 0.32 (μm), the paint used is an epoxy / urea based resin in the resin layer, and the lubricant type is polyethylene. It is the same in that the wax (melting point 90 ° C.), the addition amount (wt%) of the lubricant is 2.50, the S compound contained is dinonylnaphthalenedisulfonic acid, and the addition amount (wt%) is 1.0. . Also, the baking conditions of Invention Example 2 to Invention Example 6 were T1 (s) of 10, T2 (s) of 20, T2-T1 (s) of 10, final curing temperature (° C.) of 240, all The baking time (s) is 40, the extraction rate (%) is 17 to 19, and the number of holes (pieces / square mm) on the surface of the resin layer after MEK cleaning is diameter: resin layer thickness x 2 or more. 38 to 47, diameter: resin layer thickness x less than 2 is 50 to 57, which is almost the same. In each of the present invention examples 2 to 6, the evaluation was that the pollution property was ◎, the outgassing property was 総, the total amount was ◎, the S compound was ◎, the Sn compound was ◎, and the Si compound was ◎.

  Invention Example 9 to Invention Example 14 are the conditions of the materials and paint used, the surface roughness Ra of the material is 0.32 (μm), the main resin in the resin layer is polyester / isocyanate, lubricant Carnauba wax (melting point 86 ° C), average particle size (μm) in the paint of granular lubricant is 6.1, addition amount of lubricant (wt%) is 2.50, S compound contained is dioctyltin oxide The addition amount (wt%) was 2.0, and in this respect, the conditions of the present invention were satisfied and were the same.

In addition, T1 (s) is 9, T2 (s) is 19, and T2-T1 (s) is 10, and the conditions of the present invention are all satisfied by setting the total baking time (s) to 40. there were.
Further, the obtained resin layer also has a resin layer thickness (μm) of 7.6 to 8.0, and the number of holes (pieces / square mm) on the surface of the resin layer after MEK cleaning is: diameter: resin layer thickness × 2 The above is 26 to 32, the diameter is less than resin layer thickness × 2, and 55 to 68, and a resin layer having a thickness of 0.1 μm or more and 22 μm or less is formed. The number of holes having a diameter of at least twice the thickness of the resin layer formed on the surface of the resin layer by dropping off the granular lubricant by washing was 100 per square mm or less .

  The present invention example 16 in which the main resin in the resin layer is an acrylic / melamine system and the present invention example 17 in which the main resin in the resin layer is vinyl chloride have a surface roughness Ra of 0.32 (μm ), The type of lubricant in the paint was polyethylene wax (melting point 140 ° C.), the average particle size (μm) in the paint of the granular lubricant was 5.2, and the amount of lubricant added (wt%) was 2.50. . Further, the solid content of the paint did not contain any compound of S, Sn, and Si.

  The baking conditions of Invention Example 16 were T1 (s) of 11, T2 (s) of 18, and therefore T2-T1 (s) of 7, final curing temperature (° C.) of 260, and total baking time (s) of 60, the resin layer thickness (μm) is 7.2, the extraction rate (%) is 17, the number of holes (pieces / square mm) on the resin layer surface after MEK cleaning is diameter: resin layer thickness x 2 or more Was 38, and the diameter was 58 less than the resin layer thickness x2.

  The baking conditions of Invention Example 17 were T1 (s) of 11, T2 (s) of 18, and therefore T2-T1 (s) of 7, final curing temperature (° C.) of 280, total baking time (s). Is 60, the resin layer thickness (μm) is 6.9, the extraction rate (%) is 16, and the number of holes (pieces / square mm) on the surface of the resin layer after MEK cleaning is: diameter: resin layer thickness × 2 The above were 44, and the diameter was less than 54 (diameter: resin layer thickness x 2).

  As a result, the present invention example 16 and the present invention example 17 were both evaluated for the contamination property ◎, the outgassing property, the total amount ◎, the S compound ◎, the Sn compound ◎, the Si compound ◎, and the molding. The sex was also rated as ○.

  Invention Example 18 to Comparative Example 23 are materials whose surface roughness Ra is 0.32 (μm), the main resin in the resin layer is epoxy / phenolic, the lubricant type is polyethylene wax (melting point 110 ° C.), The average particle size (μm) in the paint of the granular lubricant is 5.2, the addition amount (wt%) of the lubricant is 2.50, and the solid content of the paint does not contain any compound of S, Sn, Si, Manufactured using the same materials and paints.

  Inventive Example 18 to Comparative Example 23 were baked with the final curing temperature (° C.) of 240 and the total baking time (s) of 60. The resulting resin layer thickness (μm) is 6.8 to 7.3, the extraction rate (%) is 16 to 19, and a resin layer having a thickness of 0.1 μm to 22 μm is formed.

  Further, the baking conditions of Invention Example 18 to Invention Example 22 are T1 (s) of 8-18, T2 (s) of 18-26, T2-T1 (s) of 1-18, and MEK cleaning. The number of holes on the surface of the subsequent resin layer (pieces / square mm) is 8 to 96 for diameter: resin layer thickness x 2 or more, and 9 to 52 for diameter: less than resin layer thickness x 2. Met. Accordingly, the resin-coated aluminum alloy plate of the present invention is manufactured so as to satisfy (T2-T1) for 20 seconds or less, and the granular lubricant is removed by ultrasonic cleaning with MEK. The number of holes formed on the surface and having a diameter that is twice or more the resin layer thickness is 100 per square mm or less. As a result, there was no particular defect (Δ) in any of the contamination, outgas total amount, outgas S compound, outgas Sn compound, outgas Si compound, and moldability.

On the other hand, in Comparative Example 23, T1 (s) is 6, T2 (s) is 29, and thus T2-T1 (s) is 23. The number of holes on the resin layer surface after MEK cleaning (pieces / square mm) ) Was 111 in diameter: resin layer thickness x 2 or more, and 7 in diameter: less than resin layer thickness x 2. (T2-T1) exceeds 20 seconds and does not satisfy the conditions for the method for producing the resin-coated aluminum alloy plate of the present invention.
As a result, in Comparative Example 23, the contamination was poor (Δ).

  Inventive Example 24 to Inventive Example 27, the material surface roughness Ra is 0.32 (μm), the main resin in the resin layer is polyester / phenolic, the lubricant type is polyethylene wax (melting point 140 ° C.) The average particle size (μm) in the paint of the granular lubricant is 6.1, the addition amount (wt%) of the lubricant is 2.50, the Sn compound contained is tin octylate, and the addition amount (wt%) is 1. Manufactured with the same materials and paints as .5.

Inventive Example 24 to Inventive Example 27 were baked with a final curing temperature (° C.) of 300 and a total baking time (s) of 60. As a result, the resin layer thickness (μm) was 7.1 to 7. 3. The extraction rate (%) is 11 to 19, and the number of holes (pieces / square mm) on the surface of the resin layer after MEK cleaning is 25 to 30 in diameter: resin layer thickness × 2 or more. Those having a resin layer thickness of less than 2 were 43 to 54. Accordingly, Invention Example 24 to Invention Example 27 are formed by forming a resin layer having a thickness of 0.1 μm or more and 22 μm or less on one surface, and the granular lubricant is dropped off by ultrasonic cleaning with MEK and formed on the surface of the resin layer. The number of holes whose diameter is at least twice the resin layer thickness is 100 per square mm or less, and the MEK (methyl ethyl ketone, the same applies hereinafter) extraction rate of the cured resin layer is 5% or more and 40% or less. It is.
As a result, there was no particular defect (Δ) in any of the contamination, outgas total amount, outgas S compound, outgas Sn compound, outgas Si compound, and moldability.

  However, the baking conditions of Invention Example 24 are T1 (s) of 3, T2 (s) of 8, and T2-T1 (s) of 5, and 0.1% by weight or more and 10% by weight or less of Sn compound. It does not satisfy the condition that T2 in the baking process is 10 seconds or more and 40 seconds or less, and there is an outgas amount of 5 ppm or more with respect to the Sn compound (◯), which is not suitable for an HDD case of 2.5 inches or less.

  Further, the baking conditions of Example 27 of the present invention are as follows: T1 (s) is 31, T2 (s) is 41, therefore T2-T1 (s) is 10, and T2 (s) exceeds 40 seconds. What can be used as a material has a limit drawing ratio of 1.9 or more and less than 2.1 (◯).

  Inventive Example 28 to Inventive Example 31, the material has a surface roughness Ra of 0.32 (μm), the main resin in the resin layer is polyester / phenolic, and the lubricant type is microwax (melting point 140 ° C.). The average particle size (μm) in the paint of the granular lubricant is 6.1, the additive amount (wt%) of the lubricant is 2.5, the contained S compound is dinonylnaphthalenesulfonic acid, the additive amount (wt%) Was produced using the same material and paint with a 1.0.

Invention Example 28 to Invention Example 31 were baked with a final curing temperature (° C.) of 300 and a total baking time (s) of 60. As a result, the resin layer thickness (μm) was 6.9-7. 3. The extraction rate (%) is 11 to 19, and the number of holes (pieces / square mm) on the surface of the resin layer after MEK cleaning is 26 to 28 when the diameter is the resin layer thickness x 2 or more. Those having a resin layer thickness of less than 2 were 47 to 52.
As a result, there was no particular defect (Δ) in any of the contamination, outgas total amount, outgas S compound, outgas Sn compound, outgas Si compound, and moldability.

  However, the baking conditions of Inventive Example 28 were T1 (s) of 3, T2 (s) of 7, and T2-T1 (s) of 4, and 0.1 to 10% by weight of the S compound. Is not satisfied, and T2 in the baking process is not satisfied for 10 seconds or more and 40 seconds or less, and there is an outgas amount of 5 ppm or more with respect to the S compound (◯), which is not suitable for an HDD case of 2.5 inches or less. .

  Further, the baking conditions of Invention Example 31 were as follows: T1 (s) was 34, T2 (s) was 42, and therefore T2-T1 (s) was 8 and T2 (s) exceeded 40 seconds. What can be used as a material has a limit drawing ratio of 1.9 or more and less than 2.1 (◯).

  In Comparative Example 32, the surface roughness Ra of the material is 0.32 (μm), the main resin in the resin layer is epoxy / phenolic, the lubricant type is polyethylene wax (melting point 100 ° C.), and the granular lubricant paint The medium average particle size (μm) was 14.0, and the addition amount (wt%) of the lubricant was 2.5. Further, it does not contain any compound of S, Sn, and Si.

The baking conditions of Comparative Example 32 were T1 (s) of 10, T2 (s) of 20, and therefore T2-T1 (s) of 10, final curing temperature (° C.) of 240, total baking time (s). Is 60, the resin layer thickness (μm) is 6.8, the extraction rate (%) is 16, and the number of holes (pieces / square mm) on the surface of the resin layer after MEK cleaning is: diameter: resin layer thickness × 2 The above were 163, and the diameter was 11 less than the diameter: resin layer thickness × 2.
In Comparative Example 32, the average particle diameter (μm) in the paint of the granular lubricant was 14.0, the resin layer thickness x 2 or more, and the contamination was poor (Δ).

  Inventive Example 33 to Inventive Example 36 had a surface roughness Ra of 0.32 (μm), the main resin in the resin layer was polyester / melamine, and the lubricant type was polyethylene wax (melting point 100 ° C.) The average particle size (μm) in the paint of the granular lubricant is 6.1, the addition amount (wt%) of the lubricant is 2.5, the Si compound contained is 3-aminopropyltriethoxysilane, and the addition amount (wt) %) Was 1.0, and the same material and paint were used.

Inventive Example 33 to Inventive Example 36 were all baked at a final curing temperature (° C.) of 240 and a total baking time (s) of 60, and the resin layer thickness (μm) was 7.1. 7.2, the extraction rate (%) is 15 to 16, the number of holes (pieces / square mm) on the surface of the resin layer after MEK cleaning is 33 to 38 with diameter: resin layer thickness x 2 or more, Diameter: resin layer thickness x less than 2 was 53-60.
As a result, there was no particular defect (Δ) in any of the contamination, outgas total amount, outgas S compound, outgas Sn compound, outgas Si compound, and moldability.

However, the baking conditions of Inventive Example 33 were T1 (s) of 4, T2 (s) of 9, and T2-T1 (s) of 5, and 0.1 to 10% by weight based on the solid content of the paint. % Of the Si compound is contained, and the condition that T2 in the baking process is 10 seconds or more and 30 seconds or less is not satisfied, and although it can be used as an HDD case material, the limit drawing ratio is 1.9 or more and less than 2.1 (○).

  Further, the baking conditions of Invention Example 36 were T1 (s) 24, T2 (s) 31, T2-T1 (s) 7 and T2 (s) exceeding 30 seconds. There is an outgas amount of 5 ppm or more (◯), which is not suitable for an HDD case of 2.5 inches or less.

  In Invention Example 37, the surface roughness Ra of the material is 0.32 (μm), the main resin in the resin layer is polyester / melamine, the lubricant type is polyethylene wax (melting point 100 ° C.), and the granular lubricant is The average particle size (μm) in the paint was 6.1, and the addition amount (wt%) of the lubricant was 2.50. Unlike Invention Example 33 to Invention Example 36, it does not contain 3-aminopropyltriethoxysilane, which is a Si compound, and does not contain any compound of S, Sn, or Si.

The baking conditions of Invention Example 37 were T1 (s) of 10, T2 (s) of 20, and T2-T1 (s) of 10, final curing temperature (° C.) of 240, total baking time (s ) Is 40, the resin layer thickness (μm) is 7.3, the extraction rate (%) is 17, and the number of holes (pieces / square mm) on the surface of the resin layer after MEK cleaning is: diameter: resin layer thickness × It was 35 that was 2 or more, and 55 that was less than diameter: resin layer thickness × 2. As a result, evaluation was obtained that the contamination property was ◎, the outgassing property was 総, the total amount was ◎, the S compound was ◎, the Sn compound was ◎, and the Si compound was ◎. However, as for formability, although it can be used as an HDD case material, the limit drawing ratio was 1.9 or more and less than 2.1 (◯).

  Inventive Example 38 to Inventive Example 41 are materials whose surface roughness Ra is 0.32 (μm), the main resin in the resin layer is epoxy / acrylic, and the lubricant type is polyethylene wax (melting point 100 ° C.) The average particle size (μm) in the paint of the granular lubricant is 6.1, the added amount of the lubricant (wt%) is 2.5, and the contained S compound is paratoluenesulfonic acid, the same material and the same kind Manufactured using paint.

  The baking conditions of Invention Example 38 to Invention Example 41 were T1 (s) of 10, T2 (s) of 20, T2-T1 (s) of 10, final curing temperature (° C.) of 240, all The baking time (s) is the same condition of 40. As a result, the resin layer thickness (μm) is 7.1 to 7.8, the extraction rate (%) is 11 to 38, and the surface of the resin layer after MEK cleaning is The number of holes (pieces / square mm) was 37 to 40 for diameter: resin layer thickness x 2 or more, and 51 to 64 for diameter: less than resin layer thickness x 2. As a result, there was no particular defect (Δ) in any of the contamination, outgas total amount, outgas S compound, outgas Sn compound, outgas Si compound, and moldability.

However, in Example 38 of the present invention, the addition amount (wt%) of paratoluenesulfonic acid was 0.05, and in Example 39 of the present invention, the addition amount (wt%) of paratoluenesulfonic acid was 1.2. The amount of addition of paratoluenesulfonic acid (wt%) was 8, and Example 41 of the invention had an addition amount of paratoluenesulfonic acid (wt%) of 13.
Therefore, the present invention example 38 does not reach the condition that the solid content of the paint contains 0.1% by weight or more and 10% by weight or less of the S compound, and as a result, the moldability is limited so that it can be used as an HDD case material. The aperture ratio was 1.9 or more and less than 2.1 (◯).
Inventive Example 41 contains an S compound exceeding the conditions of the present invention, the total outgas amount is 10 ppm or more (◯), the S compound has an outgas amount of 5 ppm or more (◯), 2.5 inches or less. It is not suitable for the HDD case.

  Inventive Example 42 to Inventive Example 45 have a surface roughness Ra of 0.32 (μm), the main resin in the resin layer is polyester / isocyanate, and the lubricant type is polyethylene wax (melting point 100 ° C.). The average particle size (μm) in the paint of granular lubricant is 6.1, the added amount of lubricant (wt%) is 2.50, and the contained Sn compound is monobutyltin trioctate, the same material and the same kind of paint It was manufactured using.

    The baking conditions of Invention Example 42 to Invention Example 45 were T1 (s) of 10, T2 (s) of 20, T2-T1 (s) of 10, and final curing temperature (° C.) of 240, Total baking time (s) is 40, resin layer thickness (μm) is 7.7 to 7.9, extraction rate (%) is 18 to 19, and the number of holes on the resin layer surface after MEK cleaning (pieces / square) mm), the diameter: resin layer thickness x 2 or more was 38 to 41, and the diameter: resin layer thickness x 2 was 55 to 60. As a result, there was no particular defect (Δ) in any of the contamination, outgas total amount, outgas S compound, outgas Sn compound, outgas Si compound, and moldability.

However, in Example 42 of the present invention, the addition amount of monobutyltin trioctate (wt%) was 0.06, in Example 43 of the present invention, the addition amount of monobutyltin trioctate (wt%) was 1.1, and in Example 44 of the present invention, monobutyltin trioctate was added. The addition amount (wt%) was 8, and Inventive Example 45 had a monobutyl tin trioctate addition amount (wt%) of 12.
Therefore, the present invention example 42 does not reach the condition that the solid content of the paint contains 0.1 wt% or more and 10 wt% or less of Sn compound, and as a result, the moldability is limited to that which can be used as an HDD case material. The aperture ratio was 1.9 or more and less than 2.1 (◯).
Inventive Example 45 contains Sn compounds exceeding the conditions of the present invention, the total outgas amount is 10 ppm or more (◯), and there is an outgas amount of 5 ppm or more with respect to the Sn compound (◯), 2.5 inches or less. It is not suitable for the HDD case.

  Inventive Example 46 to Inventive Example 49 had a surface roughness Ra of 0.32 (μm), the main resin in the resin layer was epoxy / urea, and the lubricant type was polyethylene wax (melting point 100 ° C.). The average particle size (μm) in the paint of the granular lubricant is 6.1, the additive amount (wt%) of the lubricant is 2.5, and the same material and the same kind of paint are used with the Si compound contained as aminosilane. Manufactured.

  The baking conditions of Invention Example 46 to Invention Example 49 were T1 (s) of 10, T2 (s) of 20, T2-T1 (s) of 10, and final curing temperature (° C.) of 260, Total baking time (s) is 40, resin layer thickness (μm) is 7.8-8.3, extraction rate (%) is 13-16, number of holes on resin layer surface after MEK cleaning (pieces / square mm) was 30 to 35 in diameter: resin layer thickness × 2 or more, and 60 to 64 in diameter: less than resin layer thickness × 2. As a result, there was no particular defect (Δ) in any of the contamination, outgas total amount, outgas S compound, outgas Sn compound, outgas Si compound, and moldability.

However, in the present invention example 46, the aminosilane addition amount (wt%) is 0.07, in the present invention example 47, the aminosilane addition amount (wt%) is 1.3, and in the present invention example 48, the aminosilane addition amount (wt%) In Example 49 of the present invention, the amount of aminosilane added (wt%) was 12.
Therefore, the present invention example 46 does not satisfy the condition that the Si compound is 0.1 wt% or more and 10 wt% or less in the resin layer, and as a result, the moldability is limited so that it can be used as an HDD case material. The aperture ratio was 1.9 or more and less than 2.1 (◯).
Inventive Example 49 contains a Si compound exceeding the conditions of the present invention, and the total outgas amount is 10 ppm or more (◯). Regarding the Si compound, the outgas generated when heated at 200 ° C. for 30 minutes is GC- When analyzed by MS, the condition that the detected value of Si compound is 5 ppm or less in terms of n-hexadecane is not satisfied, there is an outgas amount of 5 ppm or more (○), and it is not suitable for HDD cases of 2.5 inches or less It is.

  In Invention Example 50 to Invention Example 53, the main resin in the resin layer is epoxy / urea, the lubricant type is carnauba wax (melting point: 86 ° C.), and the granular lubricant has an average particle diameter (μm) of 5 in the paint. .2, a coating material under the same conditions in which the addition amount (wt%) of the lubricant was 2.5, the S compound contained was dinonylnaphthalenedisulfonic acid, and the addition amount (wt%) was 1.0.

  The baking conditions of Invention Example 50 to Invention Example 53 are T1 (s) of 10, T2 (s) of 20, T2-T1 (s) of 10, and final curing temperature (° C.) of 240, The total baking time (s) was set to 40 and the same conditions were set. As a result, the resin layer thickness (μm) is 6.9 to 7.2, the extraction rate (%) is 16 to 19, and the number of holes (pieces / square mm) on the surface of the resin layer after MEK cleaning is the diameter: Resin layer thickness x 2 or more was 36 to 38, and diameter: resin layer thickness x 2 was 57 to 59. As a result, there was no particular defect (Δ) in any of the contamination, outgas total amount, outgas S compound, outgas Sn compound, outgas Si compound, and moldability.

However, the present invention example 50 has a surface roughness Ra of 0.04 (μm), the present invention example 51 has a surface roughness Ra of 0.15 (μm), and the present invention example 52 The surface roughness of the material was 0.40 (μm) in Ra, and in Example 53 of the present invention, the surface roughness of the material was 0.53 (μm) in Ra.
Therefore, Invention Example 50 and Invention Example 53 do not satisfy the condition that the surface roughness of the aluminum alloy plate is 0.1 μm or more and 0.5 μm in Ra (centerline average roughness). Although it can be used as an HDD case material, the limit drawing ratio was 1.9 or more and less than 2.1 (◯).

In Comparative Example 54, Comparative Example 57, Invention Example 55, and Invention Example 56, the surface roughness of the material is 0.32 (μm) in Ra, the main resin in the resin layer is polyester / melamine, and the type of lubricant Is a polyethylene wax (melting point 105 ° C.), the average particle size (μm) of the granular lubricant is 6.1, the Sn compound contained is dibutyltin oxide, and its addition amount (wt%) is 2.0. Manufactured using the same materials and types of paint.

The baking conditions of Comparative Example 54, Comparative Example 57, Invention Example 55, and Invention Example 56 are T1 (s) of 10, T2 (s) of 20, and T2-T1 (s) of 10. A coating resin having a curing temperature (° C.) of 230 and a total baking time (s) of 40, resulting in a resin layer thickness (μm) of 7.4 to 8.0 and an extraction rate (%) of 18 to 20. A resin-coated aluminum alloy sheet having a layer was obtained.

  The number of holes (pieces / square mm) on the surface of the resin layer after MEK cleaning in Example 55 of the invention is 5: diameter: resin layer thickness x 2 or more, and diameter: less than resin layer thickness x 2 The thing was 23. As a result, the evaluation was that the contamination property was ◎, the outgassing property was 総, the total amount was ◎, the S compound was ◎, the Sn compound was ◎, the Si compound was ◎, and the moldability was also ◎.

  In addition, the number of holes (pieces / square mm) on the surface of the resin layer after MEK cleaning in Example 56 of the present invention is 87 in diameter: resin layer thickness × 2 or more, and diameter: less than resin layer thickness × 2. Some were 106. As a result, the contamination property was evaluated as ○, and the outgassing property was evaluated as 総, the total amount was ◎, the S compound was ◎, the Sn compound was ◎, the Si compound was ◎, and the moldability was also ◎.

However, Comparative Example 54, Comparative Example 57, Invention Example 55, and Invention Example 56 differ in the amount of addition of lubricant (wt%), with Comparative Example 54 being 0.04 and Invention Example 55 being 0.2. Invention Example 56 was 4.6, and Comparative Example 57 was 5.50. Therefore, Comparative Example 54 and Comparative Example 57 do not satisfy the conditions of the present invention in which the resin layer is formed by a paint in which a granular lubricant is added in an amount of 0.1 wt% to 5.0 wt% with respect to the solid content. Therefore, the number (holes / square mm) of holes on the surface of the resin layer after the MEK cleaning in Comparative Example 54 is 0 when the diameter is greater than the resin layer thickness × 2 and less than the diameter is less than the resin layer thickness × 2. The result was 9, the limit drawing ratio was 1.9 or more and less than 2.1, and the moldability was (◯).

In Comparative Example 57, the number of holes (pieces / square mm) on the surface of the resin layer after the MEK cleaning was 110 having a diameter: resin layer thickness × 2 or more. As a result, the number of particles per liter of MEK exceeded 1000 and the contamination was poor (Δ).

As described above, all of the examples of the present invention are excellent in contamination, outgas, and moldability, and have sufficient performance as HDD case materials. Samples in which the outgases of the S compound, Sn compound, and Si compound are all ◎ can be applied to HDDs of 2.5 inches or less. On the other hand, the comparative example has a problem in any of contamination, outgas, and moldability, and is not suitable as an HDD case material.

It is explanatory drawing which shows the presence state in the resin layer outermost surface of the granular lubricant distributed in a resin layer. It is explanatory drawing which shows the relationship between the baking temperature and time in the baking process of the manufacturing method of the resin-coated aluminum alloy plate of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Granular lubricant, 1a ... Granular lubricant which the horizontal line drawn through the center of a sphere with respect to the straight line drawn horizontally from the resin layer outermost surface is the resin layer side, 1b ... Resin A granular lubricant in which a horizontal line drawn through the center of the sphere overlaps a straight line drawn horizontally from the outermost surface of the layer, 1c... Passes through the center of the sphere with respect to a straight line drawn horizontally from the outermost surface of the resin layer Granular lubricant with no horizontal straight line on the resin layer side, 2 ... aluminum alloy layer, 3 ... resin layer, 4 ... air, 2t ... 2 times the resin layer thickness, 3a ··· The outermost surface of the resin layer, h ··· A straight line drawn in the horizontal direction from the outermost surface of the resin layer, H · · · A straight line drawn horizontally through the center of the sphere in the horizontal direction of the granular lubricant.

Claims (4)

(T2-T1) is a paint in which a granular lubricant having an average particle size of not more than twice the thickness of the resin layer formed by coating is added in an amount of 0.1 wt% to 5 wt% based on the solid content. A method for producing a resin-coated aluminum alloy plate, characterized by baking for 20 seconds or less.
T1: Time for the baking temperature to reach a temperature 6 degrees higher than the melting point of the granular lubricant T2: Time for the baking temperature to reach a temperature 100 degrees lower than the final curing temperature
2. The resin-coated aluminum alloy sheet according to claim 1, wherein a paint containing an S compound of 0.1 wt% or more and 10 wt% or less with respect to the solid content is baked so that T2 is 10 seconds or more. Production method.
T2: Time for the baking temperature to reach a temperature 100 degrees lower than the final curing temperature
2. The resin-coated aluminum alloy sheet according to claim 1, wherein a paint containing an Sn compound of 0.1 wt% or more and 10 wt% or less based on solid content is baked so that T2 is 10 seconds or more. Production method.
T2: Time for the baking temperature to reach a temperature 100 degrees lower than the final curing temperature
2. The resin-coated aluminum alloy sheet according to claim 1, wherein a paint containing a Si compound of 0.1 wt% or more and 10 wt% or less based on solid content is baked so that T2 is 30 seconds or less. Production method.
T2: Time for the baking temperature to reach a temperature 100 degrees lower than the final curing temperature

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