JPS6227436A - Pretreatment of stainless steel - Google Patents

Abstract

PURPOSE:To improve the wettability of a stainless steel with a synthetic resin or a plastic, by pretreating the stainless steel with a coupling agent in forming a composite of a stainless steel with a synthetic resin or a plastic. CONSTITUTION:In forming a composite of a stainless steel with a synthetic resin or a plastic, the stainless steel is kneaded with agitation with 0.1-5wt%, based on this stainless steel, at least one selected from among a titanate coupling agent, a silane coupling agent and a nonionic coupling agent. Examples of said stainless steel include stainless steel foil powders, stainless fibers, woven fabrics thereof and extremely thin stainless steel sheets.

Description

[Detailed Description of the Invention] <Industrial Application Field> When stainless steel is composited with synthetic resins or plastics, the present invention applies a surface treatment agent to the stainless steel in order to make them compatible with each other (wettability). Concerning a method of pre-treatment.

<Prior art and its problems> Stainless steel is widely used in buildings, vehicles, home appliances, etc. because of its excellent rigidity, corrosion resistance, and durability.

Furthermore, recently, taking advantage of the characteristics of the stainless steel materials mentioned above,
Composite materials of stainless steel, synthetic resins, and plastics are being researched and developed.

For example, synthetic resin paint containing stainless steel foil powder (#
(Disclosed in Japanese Patent Application No. 80-068765), electromagnetic shielding paint, and reinforced plastic 2, which is a composite of stainless steel fiber, textile, and plastic.

However, these stainless steels have a drawback of poor wettability with synthetic resins and plastics, and have not been put to practical use.

Therefore, as a result of intensive research, the present inventors have arrived at the method of pretreating stainless steels of the present invention.

<Objective of the Invention> The object of the invention is to provide a method for pre-treating stainless steel, which eliminates the drawbacks of the above-mentioned prior art and improves the wettability of stainless steel, composite resins, and plastics. It is in.

<Structure of the invention> Such objects are achieved by the present invention as described below.

That is, the present invention, when combining stainless steels with synthetic resins or plastics, combines the stainless steels with a titanate coupling agent in an amount of 0.1 to 5% by weight based on the total weight of the stainless steels, This is a method for pre-treating stainless steels, which is characterized by stirring together one or more of a silane coupling agent and a nonionic coupling agent.

Hereinafter, the method for pretreating stainless steels of the present invention will be explained in detail.

In the present invention, stainless steels and a surface treatment agent to be described later are cross-mixed.

This stainless steel surface treatment agent is one or a combination of two or more selected from titanate coupling agents, silankers, bling agents, and nonionic coupling agents.

Specifically, titanate coupling agents include isopropyl triisoste 70yl titanate, isopropyl tridodecyl benzenesulfonyl titanate, tetra(2,
2-Diallyloxymethyl-1-butyl)bis(di-
(tridecyl) phosphite titanate, etc. Silanker 7 Pulling agents include vinyl trichlorosilane, vinyl triethquin silane, vinyl tris(β-methoxyethoxy) silane, etc., and nonionic coupling agents include polyoxyethylene laurate, polyoxyethylene laurate, etc. Examples include oxyethylene stearate and polyoxyethylene oleate.

One type of these surface treatment agents is effective, but depending on the combination of stainless steel, synthetic resins, and plastics, and depending on the type of additives other than the surface treatment agent added, combinations of two or more types may be effective. It may be more effective.

Therefore, the above-mentioned surface treating agents can be used alone or in combination of two or more.

These surface treatment agents are suitable for stainless steels, synthetic resins,
Because it has a coupling effect, an affinity effect and a cilia effect on plastics, as a result, stainless steels are better wetted by synthetic resins and plastics.

The amount of such surface treatment agent added is 0.1 to 5% by weight based on the total weight of the stainless steel.

This is because if it is less than 0.1% by weight, the surface treatment effect will not be sufficiently exhibited, and if it exceeds 5% by weight, it may have an adverse effect on the physical properties of synthetic resins and plastics.

Stainless steel refers to stainless steel foil powder, stainless steel fiber or fabric thereof, and ultrathin stainless steel plate, but is not particularly limited to these.

Any stainless steel can be used in the present invention, and is appropriately selected depending on the intended use.

Preferred examples are listed below.

(1) Stainless steel foil powder used in a synthetic resin paint containing a stainless steel foil with a deciduous sediment layer formed in the synthetic resin, the size of which is 0.1-5μ layer thick, 10-30μ thick
gm, width 5 to 2 o JL or so. Ultra-thin pieces are preferred.

(2) Stainless steel foil powder or its woven fabric or stainless steel foil powder when composing reinforced plastic by composite
foil powder.

(3) Ultra-thin stainless steel plate made by laminating stainless steel plate and plastic in a sandwich structure.

(4) Stainless steel in the form of foil, powder, fiber, or fabric when used as a structure such as a housing.

Stainless steel types are corrosion resistant, weather resistant, chemical resistant, #
There are no particular limitations as long as it has excellent abrasion resistance, and one or a combination of stainless steels specified in JIS 01301.4302 etc. may be selected, and even stainless steel alloys may be used. It is also possible to use

A wet ball mill method can be used to knead and stir such stainless steels and the surface treatment agent.

The wet ball mill method (diameter 900 mmφ x 300 sentences) will be explained below.

First, the retardant (beef tallow) attached to the stainless steel foil powder
Wash and degrease with a solvent.

In this case, since prolonged stirring and washing will unnecessarily pulverize the foil powder, the washing time should be limited to within 30 minutes.

This washing is performed twice by changing the solvent, and the solvent is removed using a centrifuge.

During cleaning, the ratio of stainless steel foil powder to solvent is 1:2.

(Weight ratio) Next, in order to perform surface treatment on the washed and degreased stainless steel foil powder, add a coupling agent of 0.1~
5% by weight (weight% of foil powder) and stainless steel foil powder are mixed and stirred for about 30 minutes using the same weight ratio as in the washing step, and the entire surface of the stainless steel foil powder is coated with the coupling agent. After treatment, the solvent is squeezed out using a filter press.

Stainless steels that have been surface treated in this way are
Compounded with synthetic resins or plastics.

Any synthetic resin or plastic can be used.

For example, for paints, alkyd resins, aminoalkyd resins, chlorinated rubber, vinyl chloride resins, polyvinyl resins, polyvinyl butyl resins, silicone resins, polyester resins, acrylic resins, polyurethane resins, epoxy resins, fluororesins, etc. are used. It will be done.

The housing structure is made of acrylic-butadiene-styrene copolymer, polypropylene, polyphenylene oxide,
Polyamide (nylon), polyacetal, polycarbonate, polybutylene terephthalate, polyterylate and other plastics are used.

Plastics such as polyvinyl chloride, polyethylene, polystyrene, polyester resin, acrylic resin, phenol resin, epoxy resin, urethane resin, and melamine resin are used as the reinforced plastic.

<Example> Examples and comparative examples of the present invention regarding synthetic resin paints containing stainless steel foil powder will be shown.

(Example 1-1) Stainless steel foil powder (SUS 318 L, thickness 0.
1~0.5 jLm x width 5~207zm x length 10~3
0 μm) 1 to 2 parts by weight of isopropyl tridecylbenzene φ sulfonyl titanate as a surface treatment agent was added to 300 parts by weight of the surface treatment agent, and surface treatment was carried out by kneading and stirring using a wet ball mill method. A paint A was prepared by blending 3 parts by weight of an anti-settling agent and thoroughly kneading the mixture by a conventional method.

(Comparative Example 1-1) Paint B was prepared in the same manner as in Example 1-1 except that the surface treatment of the stainless steel foil powder was not performed.

(Comparative Example 1-2) A commercially available alkyd resin paint C containing no stainless steel foil powder was prepared.

The above paints A and B were applied to a steel plate in one coat using a conventional airless sprayer to a dry film thickness of 40 to 50 g without dripping.

Paint C is coated with primer twice on the steel plate x dry film thickness 25.
LL11/10 coats, 1 coat, dry film thickness 50JLl, was coated at predetermined intervals.

Cross-sectional micrographs of paints A and B are shown in FIGS. 1 and 2.

As is clear from FIG. 1, paint A of Example 1-1 has good wettability, so that the stainless steel foil powder is deposited in a deciduous manner in an orderly manner. On the other hand, comparative example 1-1
With paint B, the wettability was poor, so as shown in Figure 2, deciduous deposition was incomplete.

Furthermore, JIS K540 is applied to the painted surfaces of paints A and B.
Pencil scratch test according to 0, boiling water resistance, acid resistance (5% sulfuric acid solution), alkali resistance (5% caustic soda solution),
A salt spray test was conducted.

The test method is as follows. The results are shown in Table 1.

(1) Hardness (Pencil Scratch Test) a) The scratch resistance of the paint film is tested by changing the hardness of the pencil lead and the tearing of the paint film is examined.

b) A JIS K 5401 standard scratch tester was used.

C) A Mitsubishi Uni pencil was used.

Sharpen the pencil (approximately 3 mm in advance into a cylindrical shape) Place it on a hard flat surface and sharpen it gently using a 400-grit grinder according to JIS R6252 while drawing a circle at right angles so that the tip is flat and the corners are sharp.

The tip must be sharpened again each time it is scratched.

(Test method) For each paint A-C, a steel plate (150X75Xl mm
) was coated on one side according to JIS K 5400-3.5, and after drying for 3 days, it was placed in a desiccator for 244 hours to prepare a test piece.

Attach this test piece to the testing machine and load 1.0±0.05k.
g, the tip of the pencil lead touches the painted surface and the load of the weight is applied to the tip, rotate the handle (at a constant speed), and move the test piece about 3 mm above the water in the opposite direction of the lead. , the paint surface was inspected for tears. The speed of movement is approximately 0. Fv+
m/, sec.

If the test piece is scratched 5 times in the direction of movement and the paint film reaches the fabric of the test plate, or if it is observed 2 times or more than 2 times out of 5 times, lower the pencil hardness by one level and replace it, and then perform the test. , Record the pencil hardness when the pencil breaks less than twice.

(Judgment) For two pencils with hardness symbols next to each other, break or 2
1 time or more than 2 times and 1 with no break or 1 same grade
The latter case is taken as the pencil scratch value of the paint film.

Paint A-6H Paint B-6H The paint was C-F.

(2) #Boiling water test Apply paints A to C to 4 test pieces in the same way as in the pencil hardness test, dry them, and prepare one beaker for each test plate, up to a depth of 80 a + m. Add water and heat it with a heater from the bottom so that 2 to 3 small bubbles appear every second.

Hang the test plate in this with the dry top end down and the bottom end 20+m above the bottom of the beaker.
Dip to a depth of 0mm and heat continuously. To replenish the evaporated water, gradually use pre-heated hot water to compensate for the evaporated water.

The test values were determined based on the observation results based on the following criteria for three test plates of each paint.

(Judgment) When two or more of the three test panels have wrinkles, blisters, cracks, or peeling of the coating, remove them from the beaker and observe the coating.After draining the coating and leaving it indoors for 2 hours, Furthermore, observe the paint film to see the degree of cloudiness, whitening, and discoloration. Test plates on which any abnormality was observed during the above two observations were compared in advance with the observation photographs taken during the course of the test, and the test of the test plate was carried out at the time when no change was observed when compared with the thick plate. value.

Paint A-310Hr Paint B-100Hr Paint C-1) 1r.

(3) Acid resistance (sulfuric acid 5%) #Make three test plates and one thick plate in the same way as the boiling water test.

One glass container was prepared for each test plate, filled with 5% sulfuric acid solution to a depth of 150 mm, and the test piece was immersed to a depth of 120 mm at room temperature.

The occurrence of blistering, cracking, peeling, holes, etc. in the paint film was observed periodically, and the elapsed time was taken as the test value. (For two or more test panels) Paint A - 8 months Paint B - 3 months Paint Ci - I months.

(4) Alkali resistance (caustic soda 5%) Prepare three test plates and one original plate in the same way as the boiling water resistance test. Prepare one glass container for each test plate and fill it with a 5% caustic sorter.
The test piece was immersed in a solution to a depth of 120 mm at room temperature to a depth of 120 mm, and the occurrence of blistering, cracking, peeling, holes, etc. in the coating film was periodically observed, and the elapsed time at the time of occurrence was taken as the test value.

Paint A-6 months Paint B-3 months The paint was ci months old.

(5) Salt water spray test Three test pieces and one original plate were prepared in the same manner as those prepared above.

The testing machine specified in JIS Z 2371 was used.

Suga Test Instruments (C: ASSER-IR-2F) was used.

On the test piece, two diagonal lines were drawn in advance on the coating film using a cutter knife so as to reach the fabric of the test plate.

This test plate was installed in a predetermined position in the testing machine room, and during continuous operation, the progress of the coating film on the test plate was observed for rusting, blistering, and those that became 31 or more on both sides of the diagonal line, and were taken as test values.

Paint A-3000Hr or more (ongoing) Paint B-2000Hr The paint was C-320Hr.

(6) Thick coating property (as seen by sagging of paint) test piece (5PC
G), the paint was applied using an airless sprayer while it was held vertically, and while it was drying, the applied paint layer partially flowed downward, creating areas with uneven thickness. The test value was the dry film pressure obtained seven times without becoming semicircular, icicle-like, or wavy.

Paint A-40-50 pots ra/time Paint B-15 to 20 uLm/time.

From the above, it can be seen that paint A has better corrosion resistance and durability than paint B.

Next, examples and comparative examples of the present invention regarding reinforced plastics containing stainless steel foil powder will be shown.

(Example 2-1) Stainless steel foil powder (SOS 318 L, thickness 0.
1~0.5 gya x width 5~20gm x length 10~30
1 to 2 parts by weight of isopropyltriisostearoyl titanate as a surface treatment agent was added to 300 parts by weight of gm), kneaded and stirred using a wet ball mill method to perform surface treatment on the stainless steel foil powder, and then mixed with 700 parts by weight of polyacetal resin. A compound was prepared by blending and kneading thoroughly by a conventional method, and further heat molding was performed to prepare a reinforced plastic D.

(Example 2-2) Example except that 1 to 2 parts by weight of vinyltriethoxysilane was used as a surface treatment agent? Paint E was prepared in the same manner as in -1.

(Comparative Example 2-1) Reinforced plastic F was created in the same manner as in Example 2-1 except that the surface treatment of the stainless steel foil powder was not performed.

(Comparative Example 2-2) Reinforced plastic G was prepared in the same manner as Comparative Example 2-1 except that glass flakes were used instead of stainless steel foil powder.
It was created.

Reinforced plastics D, E of these Examples and Comparative Examples,
Various physical property tests were conducted on F and G. The results are shown in Table 2.

The above results show that reinforced plastics D and E have higher strength than reinforced plastics F and G, and it is confirmed that the adhesiveness between stainless steel foil powder and polyacetal resin in reinforced plastics D and E is extremely good. It was done.

<Effects of the Invention> According to the pretreatment method for stainless steel and steels of the present invention, 0.1% of the total weight of stainless steel and stainless steels is
~5% by weight of one or two of titanate coupling agents, silane coupling agents, and nonionic coupling agents
By kneading and stirring two or more types, the wettability between stainless steels and synthetic resins or plastics can be improved.

Due to this.

(1) In a synthetic resin paint containing stainless steel foil powder, since the stainless steel foil powder is deposited in an orderly and reliable manner, corrosion resistance, durability, and thick coating properties are improved.

(2) In reinforced plastics made by combining stainless steels and plastics, the bond between the stainless steels and the plastics becomes strong, making it possible to obtain extremely strong reinforced plastics.

[Brief explanation of drawings]

FIGS. 1 and 2 are photographs substituted for drawings showing the particle structure. FIG. 1 is a micrograph (200x magnification) showing the arrangement of stainless steel foil powder pretreated according to the present invention in an alkyd resin coating. FIG. 2 is a micrograph (200x magnification) showing the arrangement of stainless steel foil powder without pretreatment according to the invention in an alkyd resin coating.

Claims (1)

[Claims] (1) When combining stainless steels with synthetic resins or plastics, the stainless steels are combined with a titanate coupling agent or a silane cup in an amount of 0.1 g to 5% by weight based on the total weight of the stainless steels. A method for pretreating stainless steels, which comprises kneading and stirring one or more of a ring agent and a nonionic coupling agent.