JP2011174133A - Method for manufacturing surface-roughened stainless steel sheet, composite formed of stainless steel sheet joined with molding of thermoplastic resin composition, and method for manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a surface-roughened stainless steel sheet, which can form a pit having an overhanging part regardless of the types of a stainless steel sheet and surface finish, and does not lower corrosion resistance of the stainless steel sheet. <P>SOLUTION: This manufacturing method includes forming a plurality of pits on the surface of the stainless steel sheet by immersing the stainless steel sheet in a treatment liquid which has been prepared by dispersing inorganic compound particles having an average particle diameter in a range of 0.01-40 μm in an aqueous solution of ferric chloride, so as to be 0.1-25 g/L by concentration. The pits in an amount of 60% or more by the number of pieces among the formed pits have a ratio D<SB>1</SB>/D<SB>2</SB>of 1.05 or more, which is the ratio of the maximum diameter D<SB>1</SB>in the pit to the diameter D<SB>2</SB>of the pit aperture. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method for producing a roughened stainless steel plate, a composite in which a stainless steel plate and a molded body of a thermoplastic resin composition are joined, and a method for producing the same.

  As a technique for integrating a metal and a resin, a method of bonding with an adhesive is known. In recent years, a method (insert injection molding bonding method) has been proposed in which an aluminum alloy and a thermoplastic resin are joined by injecting a thermoplastic resin into an injection mold in which an aluminum alloy is inserted (for example, a patent). References 1-3). In the methods of Patent Documents 1 to 3, adhesion is improved by treating the surface of the aluminum alloy with a predetermined aqueous solution to form fine irregularities on the surface of the aluminum alloy.

  On the other hand, a method has been proposed in which the surface of a stainless steel plate is roughened to improve the adhesion between the stainless steel plate and a coating material (such as a coating film or a rubber layer) (see, for example, Patent Documents 4 and 5). In the methods of Patent Documents 4 and 5, the surface of the stainless steel sheet is roughened by alternating electrolysis of the stainless steel sheet in a ferric chloride aqueous solution (for example, Patent Document 5).

JP 2006-027018 A JP 2004-050488 A JP 2005-342895 A Japanese Patent Laid-Open No. 10-259499 JP 2002-106718 A

  Even if the above-mentioned insert injection molding bonding method is applied to join the stainless steel plate and the thermoplastic resin, sufficient adhesion cannot be obtained, and the adhesiveness of the thermoplastic resin particularly deteriorates with time. There was a case. Therefore, for example, when the contents are sealed in a container manufactured by the insert injection molding bonding method and stored for a long time, the contents may leak.

  As a means for improving the adhesion between the stainless steel plate and the thermoplastic resin, as described in Patent Documents 4 and 5, the stainless steel plate is subjected to alternating electrolysis in a ferric chloride aqueous solution and applied to the surface of the stainless steel plate. It is conceivable to form pits that can exhibit the anchor effect. As described in Patent Document 5, in order to exert an excellent anchor effect, it is preferable to form a pit having an overhang portion. However, the method using electrolytic surface roughening treatment has to prepare a rectifier, an electrode corresponding to the shape of the stainless steel plate, and the like, and is not a method that anyone can easily implement from the viewpoint of cost and the like.

  Then, this inventor tried to form the pit which has an overhang part on the surface of a stainless steel plate by immersing a stainless steel plate in ferric chloride aqueous solution. However, in the immersion treatment with the ferric chloride aqueous solution, pits having an overhang portion may not be formed depending on the type of stainless steel plate and the type of surface finish.

  The present invention has been made in view of such points, and is a method for producing a roughened stainless steel sheet that can impart good adhesion when a resin is brought into contact with the surface of the stainless steel sheet, It is an object of the present invention to provide a method capable of easily forming a pit having an overhang portion regardless of the type of stainless steel plate or the type of surface finish.

  Another object of the present invention is to provide a composite in which a stainless steel plate and a molded body of a thermoplastic resin composition are joined, and the composite having excellent adhesiveness of the thermoplastic resin composition.

  The present inventor has found that the above problem can be solved by treating the surface of the stainless steel plate with a ferric chloride aqueous solution containing inorganic compound particles, and has further studied and completed the present invention.

That is, the first of the present invention relates to the following method for producing a roughened stainless steel sheet.
[1] A step of preparing a stainless steel plate, and a treatment in which inorganic compound particles having an average particle diameter of 0.01 to 40 μm are dispersed in an aqueous ferric chloride solution at a concentration of 0.1 to 25 g / L. A step of immersing the stainless steel plate in a liquid to form a plurality of pits on the surface of the stainless steel plate.
[2] The inorganic compound particles are selected from the group consisting of carbon particles, metal oxide particles, metal hydroxide particles, metal carbide particles, metal nitride particles, and metal phosphates that do not dissolve in the ferric chloride aqueous solution. The method for producing a roughened stainless steel sheet according to [1], comprising one or more selected particles.
[3] Among the plurality of pits, 60% or more of pits have a ratio D ₁ / D ₂ of the maximum diameter D ₁ inside the pit to the diameter D ₂ of the pit opening is 1.05 or more. [1] Or the manufacturing method of the roughened stainless steel plate as described in [2].

The second aspect of the present invention relates to the following complex.
[4] A composite in which a stainless steel plate and a molded body of a thermoplastic resin composition are joined: the stainless steel plate has pits in 60% by area or more of the joint surface with the molded body of the thermoplastic resin composition Among the pits formed on the joint surface, 60% or more of pits have a ratio D ₁ / D ₂ of the maximum diameter D ₁ inside the pit to the diameter D ₂ of the pit opening of 1.05 The composite shrinkage ratio of the thermoplastic resin composition is 1.0% or less.
[5] The thermoplastic resin composition includes a polyethylene resin, a polypropylene resin, a polyethylene terephthalate resin, a polybutylene terephthalate resin, a polyamide resin, a polyacetal resin, a polyphenylene sulfide resin, an acrylonitrile-butadiene-styrene resin, The composite according to [4], including one or more selected from the group consisting of an acrylic resin, a polyvinyl chloride resin, a polycarbonate resin, a phenol resin, and a perfluoro resin.

The third aspect of the present invention relates to a method for producing the following composite.
[6] A method for producing a composite in which a stainless steel plate and a molded body of a thermoplastic resin composition are joined: a step of inserting a roughened stainless steel plate into an injection mold; Injecting a thermoplastic resin composition having a molding shrinkage rate of 1.0% or less and joining the molded body of the thermoplastic resin composition to the surface of the roughened stainless steel sheet; of stainless steel sheet has pits formed in more than 60 area% of its surface; 60% by number or more pits of the pit, the ratio D of the maximum diameter D ₁ of the inner pit to the diameter D ₂ of the pit openings ₁ / _{D 2} is 1.05 or more, a manufacturing method of the composite.
[7] A stainless steel plate is immersed in a treatment liquid in which inorganic compound particles having an average particle diameter of 0.01 to 40 μm are dispersed in a ferric chloride aqueous solution at a concentration of 0.1 to 25 g / L. The method for producing a composite according to [6], further comprising the step of obtaining the roughened stainless steel plate.
[8] The inorganic compound particles are selected from the group consisting of carbon particles, metal oxide particles, metal hydroxide particles, metal carbide particles, metal nitride particles, and metal phosphates that do not dissolve in the ferric chloride aqueous solution. The manufacturing method of the composite_body | complex as described in [7] containing the particle | grains of 1 or 2 or more selected.
[9] The thermoplastic resin composition comprises a polyethylene resin, a polypropylene resin, a polyethylene terephthalate resin, a polybutylene terephthalate resin, a polyamide resin, a polyacetal resin, a polyphenylene sulfide resin, an acrylonitrile-butadiene-styrene resin, The composite according to any one of [6] to [8], including one or more selected from the group consisting of acrylic resins, polyvinyl chloride resins, polycarbonate resins, phenol resins, and perfluoro resins. Manufacturing method.

  According to the present invention, a pit having an overhang portion can be easily formed on the surface of a stainless steel plate regardless of the type of stainless steel plate or the type of surface finish. Therefore, according to the present invention, it is possible to provide a roughened stainless steel sheet capable of imparting good adhesion when a resin is brought into contact with the surface thereof. Furthermore, according to this invention, it is the composite_body | complex with which the stainless steel plate and the molded object of the thermoplastic resin composition were joined, Comprising: The composite_body | complex excellent in the adhesiveness of a thermoplastic resin composition can be provided.

It is an electron micrograph which shows the steel plate cross section after the immersion process of the stainless steel plate of Example 14. FIG. It is an electron micrograph which shows the steel plate cross section after the immersion process of the stainless steel plate of the comparative example 6. It is an electron micrograph which shows the steel plate cross section after the immersion process of the stainless steel plate of the comparative example 7.

1. Method for Producing Roughened Stainless Steel Plate The method for producing a roughened stainless steel plate according to the present invention includes 1) a first step of preparing a stainless steel plate as a base material, and 2) immersing the prepared stainless steel plate in a treatment liquid. A second step.

  In the first step, a stainless steel plate as a base material is prepared.

  The stainless steel plate used as a base material is not particularly limited, such as austenite, ferrite, and martensite. Examples of the steel type of the stainless steel plate include SUS304, SUS430, and SUS316. Further, the type of surface finish of the stainless steel plate is not particularly limited. Examples of types of surface finish include BA, 2B, 2D, No. 4, HL, and the like.

In the second step, the stainless steel plate prepared in the first step is immersed in the treatment liquid. By this step, a plurality of pits having an overhang portion are formed on the surface of the stainless steel plate. In the present specification, "pits having an overhang portion", the maximum diameter of the inner pit and D _1, the diameter of the pit openings when the D _2, D ₁ is meant greater pits than D ₂ Preferably, it means a pit having D ₁ / D ₂ of 1.05 or more (see FIG. 1).

  As the treatment liquid for immersing the stainless steel plate, a suspension in which inorganic compound particles are dispersed in a ferric chloride aqueous solution is used.

Ferric chloride (FeCl ₃ ) in the treatment liquid forms pits on the surface of the stainless steel plate by a pitting corrosion action starting from the adsorption portion of Cl ⁻ ions. The concentration of ferric chloride in the treatment liquid is preferably within the range of 0.1 to 3.0 mol / L. When the ferric chloride concentration is less than 0.1 mol / L, pits having a sufficient depth cannot be formed on the surface of the stainless steel plate. On the other hand, even if the ferric chloride concentration exceeds 3.0 mol / L, an increase in the number of pits corresponding to the increase in the ferric chloride concentration is not observed.

  The kind of inorganic compound particle | grains will not be specifically limited if it does not melt | dissolve in ferric chloride aqueous solution. Examples of the inorganic compound particles include ceramic particles such as carbon particles, metal oxide particles, metal hydroxide particles, metal carbide particles, metal nitride particles, and metal phosphate particles. Here, “metal” includes silicon (Si). These particles may be used alone or in combination of two or more.

  The average particle diameter of the inorganic compound particles is preferably in the range of 0.01 to 40 μm. When the average particle size is less than 0.01, the cohesive force of the particles becomes excessively strong, and the particles are not uniformly dispersed in the solution, so that the stability of the treatment liquid is lowered. On the other hand, when the average particle diameter exceeds 40 μm, pits having an overhang portion cannot be formed efficiently. The average particle diameter of the inorganic compound particles is measured by a laser diffraction scattering method.

  The concentration of the inorganic compound particles in the treatment liquid is preferably within the range of 0.1 to 25.0 g / L. When the concentration of the inorganic compound particles is less than 0.1 g / L, the effect of the inorganic compound particles is hardly recognized for the formation of pits having an overhang portion. On the other hand, when the concentration of the inorganic compound particles is more than 25.0 g / L, an excessive amount of inorganic compound particles is precipitated, so that the stability of the treatment liquid is lowered.

  The liquid temperature of the treatment liquid is preferably in the range of room temperature to 95 ° C, and more preferably in the range of room temperature to 60 ° C. This is because when the liquid temperature is high, the evaporation of the treatment liquid becomes remarkable.

  The time for immersing the stainless steel plate in the treatment liquid is preferably 150 seconds or less. When the immersion time exceeds 150 seconds, the diameter of the formed pits becomes excessively large and the anchor effect is lowered. Moreover, since the remarkable improvement of an anchor effect is not recognized even if it processes for 60 seconds or more, it is more preferable that immersion time shall be 60 seconds or less. On the other hand, since the immersion treatment for 1 second or less is difficult to control, the immersion time is preferably 2 seconds or more.

  In the second step, the same effect can be obtained by applying the treatment liquid to the surface of the stainless steel plate instead of immersing the stainless steel plate in the treatment liquid. However, depending on the shape of the stainless steel plate, it is difficult to uniformly apply the treatment liquid to the surface of the steel plate, so it is preferable to form pits by dipping treatment. Moreover, when performing an immersion process, it is preferable to make stirring speed as low as possible from a viewpoint of preventing the liquid-contact defect by scattering of a process liquid or entrainment of air.

As described above, when a stainless steel plate is immersed in a ferric chloride aqueous solution, a plurality of pits having an overhang portion are formed on the surface of the stainless steel plate by the pitting action of Cl ⁻ ions derived from ferric chloride (FeCl ₃ ). Is done. However, depending on the type of the stainless steel plate and the type of surface finish, the surface of the stainless steel plate is melted and the pit opening (overhang portion) is also melted, so that a pit having an overhang portion may not be formed. For example, SUS430 has a lower immersion potential in a ferric chloride aqueous solution than SUS304, and the steel plate surface is easily dissolved as a whole. Therefore, even if SUS430 is immersed in a ferric chloride aqueous solution, the dissolution of the pit opening also proceeds in parallel with the formation of the pits. Therefore, the ratio of pits having an overhang portion among the formed pits is 60. It may be less than the number% (see FIG. 2).

  In the production method of the present invention, this problem is solved by dispersing inorganic compound particles in a ferric chloride aqueous solution. Although the mechanism by which the proportion of pits having an overhang portion can be increased by dispersing inorganic compound particles is unknown, the following mechanisms (1) to (3) are presumed.

  (1) When the inorganic compound particles are present on the surface of the stainless steel plate with a slight gap, oxygen hardly diffuses from the outside into the gap portion. Therefore, it becomes difficult to form or maintain a passive state on the surface of the stainless steel plate at the gap portion, and an oxygen concentration cell having the anode at the center of the gap portion is formed. As a result, pits are locally formed starting from the center of the gap portion, and pits having overhang portions are formed.

  (2) The inorganic compound particles are adsorbed on a portion of the stainless steel plate surface where pitting corrosion does not occur, such as a pit opening (overhang portion), and the dissolution of the portion is suppressed. As a result, pits are locally formed and pits having an overhang portion are formed.

  (3) The inorganic compound particles collide with the stainless steel plate surface and damage the oxide film (passive film). The dissolution of the portion where the oxide film is broken proceeds faster than the other portions. As a result, pits are locally formed and pits having an overhang portion are formed.

  Many pits are formed on the surface of the roughened stainless steel plate produced by the production method of the present invention (see FIG. 1). The ratio of the area of the pit forming portion to the area of the region subjected to the immersion treatment (hereinafter also referred to as “area ratio of the pit forming portion”) is 60 area% or more. The area ratio of a pit formation part can be measured by image-analyzing the electron microscope (SEM) photograph which imaged the steel plate surface which performed the immersion process from the top.

Also, if you produce a roughened stainless steel plate in the production process of the present invention, 60% by number or more of the pit of the plurality of pits formed on the steel sheet surface, the maximum diameter of the inner pit to the diameter D ₂ of the pit openings the ratio _D 1 / _{D 2} of D ₁ is 1.05 or more (see examples). That is, most of the pits formed on the steel plate surface have an overhang portion. Thus, the pit which has an overhang part improves adhesiveness with a thermoplastic resin composition by an anchor effect. That is, when the thermoplastic resin composition is brought into contact with the surface of the roughened stainless steel plate produced by the production method of the present invention, since a part of the thermoplastic resin composition enters these pits, Adhesion with the thermoplastic resin composition is improved. The diameter of the pit can be measured using an electron microscope (SEM) photograph obtained by imaging a cross section of the steel plate.

2. Composite of Stainless Steel Plate and Thermoplastic Resin Composition The composite of the present invention is a composite in which a stainless steel plate and a molded body of a thermoplastic resin composition are joined. In this specification, the area | region joined with the molded object of a thermoplastic resin composition among the surfaces of a stainless steel plate is called "joint surface."

The stainless steel plate joined to the thermoplastic resin composition is a roughened stainless steel plate produced by the production method of the present invention described above (hereinafter also referred to as “roughened stainless steel plate of the present invention”). As described above, the roughened stainless steel plate of the present invention has 1) pits formed in 60% by area or more of the joint surface (surface), and 2) of the pits formed on the joint surface (surface). In the pits of 60% by number or more, the ratio D ₁ / D ₂ of the maximum diameter D ₁ inside the pit to the diameter D ₂ of the pit opening is 1.05 or more.

  The thermoplastic resin composition may contain either a crystalline thermoplastic resin or an amorphous thermoplastic resin. Examples of the crystalline thermoplastic resin include polyethylene resin, polypropylene resin, polyethylene terephthalate resin, polybutylene terephthalate resin, polyamide resin, polyacetal resin, polyphenylene sulfide resin, and the like. Examples of non-crystalline thermoplastic resins include acrylonitrile-butadiene-styrene resins, acrylic resins, polyvinyl chloride resins, polycarbonate resins, polyacetal resins, phenolic resins and perfluoro resins (tetrafluoroethylene-perfluoroalkyl). Vinyl ether, etc.).

  The molding shrinkage of the thermoplastic resin composition is preferably 1.0% or less. The molding shrinkage ratio was determined by measuring the volume B of the resin composition solidified after injection molding with respect to the volume A of the resin inflow portion of the mold used at the time of injection molding, and “(A−B) / A × 100 (%) ".

  The molding shrinkage of the thermoplastic resin composition can be adjusted depending on the type of resin, but can also be adjusted by adding a filler, for example. Examples of fillers include fiber fillers such as glass fiber, carbon fiber, and aramid resin; carbon black, calcium carbonate, calcium silicate, magnesium carbonate, silica, talc, glass, clay, lignin, mica, quartz powder, glass sphere Powder fillers such as: carbon fiber and aramid fiber pulverized material are included, but are not particularly limited. The filler content in the thermoplastic resin composition is preferably in the range of 5 to 60% by mass, more preferably in the range of 10 to 40% by mass.

  The molding shrinkage rate of the thermoplastic resin composition can also be adjusted by mixing a crystalline resin and an amorphous resin. In general, a crystalline resin has a larger molding shrinkage ratio than an amorphous resin. Therefore, if the mixing ratio of the amorphous resin is increased, the molding shrinkage ratio can be reduced.

  In the composite of the present invention, a plurality of pits having an overhang portion are formed on the joining surface of the stainless steel plate surface. In the composite of the present invention, since the thermoplastic resin composition enters the pits of the stainless steel plate at the joining surface, the stainless steel plate and the molded body of the thermoplastic resin composition are firmly joined.

  Although the composite_body | complex of this invention is not specifically limited, For example, it can be manufactured with the following method.

3. Manufacturing method of composite of stainless steel plate and thermoplastic resin molded body The composite of the present invention is obtained by inserting the roughened stainless steel plate of the present invention into an injection mold and then applying the thermoplastic resin composition to the injection mold. It can be manufactured by injection into a mold.

  First, the roughened stainless steel plate of the present invention is inserted into an injection mold. Next, a high-temperature thermoplastic resin composition is injected into the injection mold at high pressure. At this time, it is preferable to provide a gas vent in the injection mold so that the thermoplastic resin composition flows smoothly. As described above, a plurality of pits are formed on the surface of the roughened stainless steel sheet of the present invention, and the high-temperature thermoplastic resin composition contacts the surface on which the pits are formed. The temperature of the injection mold is preferably near the melting point of the resin used. This is because the injected thermoplastic resin easily enters the pits of the roughened stainless steel plate.

  After completion of injection, the mold is opened and released to obtain a composite. The composite obtained by injection molding is preferably annealed after molding to eliminate internal distortion due to molding shrinkage.

  By the above procedure, the composite of the present invention can be produced by bonding the molded body of the thermoplastic resin composition to the surface of the roughened stainless steel plate. The composite of the present invention thus produced can exhibit excellent bondability because the thermoplastic resin composition enters the pits on the steel sheet surface.

  EXAMPLES Hereinafter, although this invention is demonstrated in detail with reference to an Example, this invention is not limited by these Examples.

1. Production of Roughened Stainless Steel Sheet The following two types of stainless steel sheets were prepared as test stainless steel sheets.
Stainless steel plate A: SUS304, 2B finish, plate thickness 0.8mm
Stainless steel plate B: SUS430, 2B finish, plate thickness 0.8mm

Each stainless steel plate (stainless steel plate A or stainless steel plate B) is subjected to alkaline degreasing (pH 12, liquid temperature 60 ° C., immersion time 1 minute), and then the conditions shown in Table 1 (liquid temperature, time) ) To form pits on the surface of each stainless steel plate. Each treatment solution is charged with a predetermined amount of FeCl ₃ .6H ₂ O (n = 270.2) or hydrochloric acid and inorganic compound particles in a beaker, and water is added so that the total amount becomes 1 L. Prepared by stirring. Each stainless steel plate after the immersion treatment was washed with running water and then dried with a hot air dryer.

For each inorganic compound particles shown in Table 1, _Al 2 _{O 3} particles (mean particle size 57 .mu.m) was used the A-13-H (manufactured by Showa Denko Co., Ltd.). As the Al ₂ O ₃ particles (average particle size 40 μm), Fuji Random WA 320 (Fuji Seisakusho Co., Ltd.) was used. As the Al ₂ O ₃ particles (average particle size 20 μm), Fuji Random WA 600 (Fuji Seisakusho Co., Ltd.) was used. As the Al ₂ O ₃ particles (average particle size 9.5 μm), Fuji Random WA 1200 (Fuji Seisakusho Co., Ltd.) was used. As the Al ₂ O ₃ particles (average particle diameter 1.2 μm), Fuji Random WA 800 (Fuji Seisakusho Co., Ltd.) was used. As the SiO ₂ particles (average particle size 0.01 μm), Leorosil QS-30 (Tokuyama Corporation) was used. TiO ₂ particles (average particle size 0.4 μm) were TA-100 (Fuji Titanium Industry Co., Ltd.). TZ-8YS (Tosoh Corporation) was used as ZrO ₂ particles (average particle size 0.5 μm). Aqua-Black001 (Tokai Carbon Co., Ltd.) was used as C particles (average particle size 0.15 μm). As the AlN particles (average particle size 1.2 μm), Toyalnite Super JC (Toyo Aluminum Co., Ltd.) was used. As the SiC particles (average particle size 0.8 μm), GMF-6S (Pacific Random Co., Ltd.) was used. The average particle diameter of the inorganic compound particles was measured using a laser diffraction particle size distribution measuring device (SALD-1100; Shimadzu Corporation). When measuring the average particle size, 0.1 g of inorganic compound particles were dispersed in 50 mL of pure water.

Each stainless steel plate having been subjected to the immersion treatment (Examples 1 to 25 and Comparative Examples 1 to 11; see Table 2), the area ratio of the pit, the ratio D of the maximum diameter D ₁ of the inner pit to the diameter D ₂ of the pit openings The ratio of pits with ₁ / D ₂ of 1.05 or more was determined.

  The area ratio of the pits is determined by observing the steel plate surface with a 500 × field of view using a laser shape measurement microscope (OLS1200; Olympus Optical Co., Ltd.) and other parts having a depth of 0.5 μm or more. The binarization process is performed so that the portion having a depth of 0.5 μm or more is colored and the other portions are not colored. And the area ratio of the colored part was calculated | required and it was set as the area ratio of a pit formation part.

Maximum diameter _{D 1} of the inner diameter _{D 2} and pits of the pit openings, FE-SEM; measured by observing at 5000 times the steel sheet section (width 200μm fraction) by using (S-4000 Hitachi High-Technologies Corporation) (See FIG. 1).

Table 2 shows the conditions of immersion treatment, the type of stainless steel plate, the area ratio of pits, and the ratio of pit diameters D _{1 for} each stainless steel plate (Examples 1 to 25, Comparative Examples 1 to 11) after the immersion treatment. / _{D 2} indicates a ratio of 1.05 or more pits. In addition, Comparative Examples 10 and 11 are untreated steel plates that are not subjected to immersion treatment.

  FIG. 1 is a photograph (SEM image) showing a steel plate surface (FIG. 1A) and a cross section (FIG. 1B) after immersion treatment of the stainless steel plate of Example 14. As shown in these photographs, the overhanging portion is obtained by immersing with an aqueous ferric chloride solution containing inorganic compound particles having an average particle size of 0.01 to 40 μm at a concentration of 0.1 to 25 g / L. It was possible to form a large number of pits having (Examples 1 to 25).

  FIG. 2 is a photograph (SEM image) showing a steel plate surface (FIG. 2A) and a cross section (FIG. 2B) after immersion treatment of the stainless steel plate of Comparative Example 6. As shown in these photographs, when immersion treatment is performed only with a ferric chloride aqueous solution, a plurality of pits are formed, but since the pit openings are dissolved, the ratio of pits having an overhang portion Was less than 60% by number (Comparative Examples 5 and 6).

  3 is a photograph (SEM image) showing a steel plate surface (FIG. 3A) and a cross section (FIG. 3B) after immersion treatment of the stainless steel plate of Comparative Example 7. FIG. As shown in these photographs, when the immersion treatment is performed with hydrochloric acid containing inorganic compound particles or hydrochloric acid not containing inorganic compound particles, the steel sheet surface is totally dissolved, so that pits having overhang portions are formed. It could not be formed (Comparative Examples 7 to 9).

As shown in Table 2, the stainless steels of Examples 1 to 25 were immersed in a ferric chloride aqueous solution containing inorganic compound particles having an average particle diameter of 0.01 to 40 μm at a concentration of 0.1 to 25 g / L. steel is the area ratio of the pits 60 area% or more, and the ratio the ratio D _{1 /} D ₂ is 1.05 or more pits of the pit diameter is 60% by number or more, the pit shape can expect an anchoring effect Many were formed.

On the other hand, the immersion treatment was performed using the stainless steel plate of Comparative Examples 1 and 4 in which the concentration of the inorganic compound particles was less than 0.1 g / L, and the treatment solution having an average particle diameter of the inorganic compound particles of more than 40 μm. In the stainless steel plates of Comparative Examples 2 and 3 and the stainless steel plates of Comparative Examples 10 and 11 that were immersed in the treatment liquid not containing particles, although the pits were formed, the pit diameter ratio D ₁ / D ₂ was 1. The ratio of pits of 0.05 or higher was less than 60% by number, and pits having a shape that could be expected to have an anchor effect were not formed.

2. Bondability test A test piece having a width of 30 mm and a length of 100 mm was cut out from each stainless steel plate (Examples 1 to 25, Comparative Examples 1 to 11) after finishing the surface roughening treatment. Moreover, the thermoplastic resin composition having the composition shown in Table 3 was filled in an injection molding apparatus and melted.

  For each resin shown in Table 3, Nipolon Hard 1000 (melting point 134 ° C .; Tosoh Corporation) was used as the polyethylene. As the polypropylene, Novatec PP MA1B (melting point: 170 ° C .; Nippon Polypro Co., Ltd.) was used. For acrylonitrile-butadiene-styrene, Techno ABS130 (melting point: 91 ° C .; Technopolymer Co., Ltd.) was used. As the polyethylene terephthalate, Rynite 530 (melting point: 230 ° C .; DuPont) was used. As the polybutylene terephthalate, Duranex 2002 (melting point: 228 ° C .; Polyplastics Co., Ltd.) was used. As the polycarbonate, Iupilon GS-2030MR2 (melting point 250 ° C .; Mitsubishi Engineering Plastics Co., Ltd.) was used. As the polyacetal, TPS-POM NC (melting point: 163 ° C .; Toyo Plastic Seiko Co., Ltd.) was used. As the tetrafluoroethylene-perfluoroalkyl vinyl ether, Fluon PFA P-65P (melting point: 310 ° C., Asahi Glass Co., Ltd.) was used. Sumicon M9640 (melting point 100 ° C .; Sumitomo Bakelite Co., Ltd.) was used as the phenol resin. As the polyphenylene sulfide, Fortron 0220A9 (melting point: 280 ° C .; Polyplastics Co., Ltd.) was used.

  Test pieces (Examples 1 to 25, Comparative Examples 1 to 11) were inserted into the injection mold, and the molten thermoplastic resin composition was injected into the injection mold. The volume of the portion into which the thermoplastic resin composition flows in the injection mold is 30 mm wide × 100 mm long × 4 mm thick, and the test piece (stainless steel plate) and thermoplastic in the region of 30 mm wide × 30 mm long. The resin composition is in contact. After injecting the thermoplastic resin composition into the injection mold, the thermoplastic resin composition was solidified to obtain a composite of the test piece and the thermoplastic resin molded body.

  Each obtained composite was subjected to a thermal shock test. Specifically, the composite is stored in a constant temperature and humidity tester A (−30 ° C., relative humidity 95%) for 30 minutes, and then immediately in the constant temperature and humidity tester B (70 ° C., relative humidity 95%). The process of transferring to and storing for 30 minutes was performed 10 cycles as 1 cycle. After finishing the thermal shock test, each composite was subjected to a tensile test, and the strength when it was broken at a pulling rate of 100 mm / min was measured. When the peel strength is 4.0 kN or more, “◎”, when it is 2.5 kN or more and less than 4.0 kN, “◯”, when it is 1.5 kN or more and less than 2.5 kN, “△”, or less than 1.5 kN Was evaluated as “×”. Table 4 shows the results of the bondability test.

In the composites of Examples 1 to 25, since the ratio of pits having a pit diameter ratio D ₁ / D ₂ of 1.05 or more on the joint surface was 60% by number or more, good evaluation was obtained regarding the bondability. . On the other hand, since the composites of Comparative Examples 1 to 11 have a ratio of pits having a pit diameter ratio D ₁ / D ₂ of 1.05 or more on the joint surface of less than 60% by number, good evaluation of the bondability is achieved. Was not obtained.

  The roughened stainless steel plate produced by the production method of the present invention is excellent in adhesiveness with a resin. For example, various electronic devices, household appliances, medical devices, automobile bodies, vehicle-mounted products, building materials, etc. Is preferably used.

Claims (9)

Preparing a stainless steel plate;
The stainless steel plate is immersed in a treatment liquid in which inorganic compound particles having an average particle diameter of 0.01 to 40 μm are dispersed in a ferric chloride aqueous solution at a concentration of 0.1 to 25 g / L, Forming a plurality of pits on the stainless steel plate surface;
A method for producing a roughened stainless steel sheet.   The inorganic compound particles are selected from the group consisting of carbon particles, metal oxide particles, metal hydroxide particles, metal carbide particles, metal nitride particles, and metal phosphates that do not dissolve in the ferric chloride aqueous solution. The manufacturing method of the roughened stainless steel plate of Claim 1 containing a 1 or 2 or more particle | grain. 2. The pit of 60% by number or more among the plurality of pits has a ratio D ₁ / D ₂ of the maximum diameter D ₁ inside the pit to the diameter D ₂ of the pit opening of 1.05 or more. Manufacturing method of roughened stainless steel sheet. A composite in which a stainless steel plate and a molded body of a thermoplastic resin composition are joined,
In the stainless steel plate, pits are formed in 60% by area or more of the joint surface with the molded body of the thermoplastic resin composition,
60% by number or more pits of the pits formed in the joint surface is at a ratio D _{1 /} D ₂ of the maximum diameter D ₁ of the pit internal to the diameter D ₂ of the pit openings 1.05 or more,
The molding shrinkage of the thermoplastic resin composition is 1.0% or less.
Complex.   The thermoplastic resin composition includes polyethylene resin, polypropylene resin, polyethylene terephthalate resin, polybutylene terephthalate resin, polyamide resin, polyacetal resin, polyphenylene sulfide resin, acrylonitrile-butadiene-styrene resin, acrylic resin. The composite according to claim 4, comprising at least one selected from the group consisting of a polyvinyl chloride resin, a polycarbonate resin, a phenol resin, and a perfluoro resin. A method for producing a composite in which a stainless steel plate and a molded body of a thermoplastic resin composition are joined,
Inserting a roughened stainless steel plate into an injection mold;
Injecting a thermoplastic resin composition having a molding shrinkage of 1.0% or less into the injection mold, and joining the molded body of the thermoplastic resin composition to the surface of the roughened stainless steel sheet; Have
The roughened stainless steel sheet has pits formed in 60% by area or more of its surface,
Of the pits, 60% or more of pits have a ratio D ₁ / D ₂ of the maximum diameter D ₁ inside the pit to the diameter D ₂ of the pit opening of 1.05 or more.
A method for producing a composite.   A stainless steel plate is immersed in a treatment liquid in which inorganic compound particles having an average particle diameter of 0.01 to 40 μm are dispersed in a ferric chloride aqueous solution at a concentration of 0.1 to 25 g / L, The manufacturing method of the composite_body | complex of Claim 6 which further has the step of obtaining a roughened stainless steel plate.   The inorganic compound particles are selected from the group consisting of carbon particles, metal oxide particles, metal hydroxide particles, metal carbide particles, metal nitride particles, and metal phosphates that do not dissolve in the ferric chloride aqueous solution. The manufacturing method of the composite_body | complex of Claim 7 containing 1 or 2 or more particle | grains.   The thermoplastic resin composition includes polyethylene resin, polypropylene resin, polyethylene terephthalate resin, polybutylene terephthalate resin, polyamide resin, polyacetal resin, polyphenylene sulfide resin, acrylonitrile-butadiene-styrene resin, acrylic resin. The manufacturing method of the composite_body | complex of Claim 6 containing 1 or more types selected from the group which consists of a polyvinyl chloride resin, a polycarbonate-type resin, a phenol-type resin, and a perfluoro-type resin.