JPH01446A - Paint film adhesion test method - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention aims to improve the measurement accuracy when measuring the adhesion force of epoxy resin paint and tar epoxy resin paint applied to each steelwork structure, etc. to a steel plate. This invention relates to a coating film adhesion testing method that makes the adhesion between the coating surface and the terminal for adhesion testing extremely strong in order to improve the adhesive strength. In particular, the present invention is applicable to ships, bridges,
The present invention relates to the above method which can be effectively applied to adhesion tests of three-dimensional network hardened coatings applied to various steel structures such as power generation plants.

[Conventional technology]

Various steel structures are coated with epoxy resin paints and tar epoxy resin paints for the purpose of corrosion prevention and are put into practical use.

A commonly used method for determining the state of deterioration of these paint films during use is to measure the adhesion between the steel plate and the paint film and compare the measured value with the value before practical use. In the conventional adhesion test method, operations from ■ to ■ are performed sequentially from ■ as shown below.

■ Remove dirt, dust, sand, oil, etc. from the paint film in the area to be investigated. If it is wet, wipe it with a rag and wait for it to dry. If salt, acid, alkali, etc. are attached, wash them with water, wipe them with a cloth, and wait for them to dry.

■ Lightly sand the surface of the paint film using sandpaper. Furthermore, wipe it gently with a cloth impregnated with a special solvent. Adhesion test terminals are also tested from ■ to ■ in the same manner as coating iK and %.

Value) After mixing a fast-curing two-component epoxy resin or a general two-component epoxy resin adhesive as specified, apply a thin layer of this adhesive to the coating film and the adhesion test terminal, then immediately put the two together, and Apply a constant load.

(2) After the adhesive has hardened (for example, after 4 to 16 hours for a fast-curing two-component resin adhesive), remove the load and cut the coating film along the outer periphery of the adhesion test terminal with a knife or the like.

■ Tensile testing machine (for example, Shimadzu Autoclaf S-5OO
, tensile speed 5/min) or using an adhesion tester (manufactured by Adhesion, UK), the adhesion force (kgf/, I') and peeling form (e.g.
(Peeling from the underlying steel plate, cohesive failure of the paint film, peeling from the surface layer of the paint film, i.e. adhesive, etc.) is measured and investigated.

[Problem that the invention seeks to solve]

The conventional method described above has the following problems.

■ It often peels off between the paint film surface and the adhesive,
Also, since the adhesion force is small, even if it can be confirmed that the object to be painted and the paint film have an adhesion force above a certain value (for example, a standard value), the true measurement value of the adhesion force between the two is required. It is not possible.

■ It is impossible to estimate the degree of deterioration because it is not possible to understand the tendency of the adhesion force to decrease before and after impact.

The present invention eliminates the problem of peeling from the paint film surface and adhesive, which is a drawback of the conventional adhesion test method as described above. The present invention provides a test method that can accurately measure the adhesion force between a pregnant object and a coating film by making the adhesion force with the agent extremely strong.

[Means for solving problems]

The present invention applies halogenated hydrocarbons, aromatic hydrocarbons, alcohols, ethers, A mixed solvent containing two or more solvents selected from at least two groups of organic solvents belonging to the six groups of NTE μ or ketones, and two or more different reactive groups bonded to silicon atoms in one molecule. General formula R8
An organosyphne compound represented by After applying a binder coat made of a mixture of This is an adhesion test method characterized by measuring the adhesion between the three-dimensional network-cured coating film and the object to be coated using a device or the like.

The binder coat used in the present invention is made of two or more solvents selected from at least two groups of organic solvents layered in six groups: halogenated hydrocarbons, aromatic hydrocarbons, alcohols, ethers, esters, or ketones. 1 in a mixed solvent containing
An organosyphne compound having two or more different reactive groups bonded to a silicon atom in the molecule is preferably used in 1.
It is obtained by blending 0 to 30% (weight %, the same applies hereinafter).

As a solvent, halogenated hydrocarbon, aromatic hydrocarbon
A mixed solvent containing two or more solvents selected from at least two groups of organic solvents belonging to the six groups of alcohols, ethers, esters, or ketones is used for three-dimensional network curing paints with excellent solvent resistance. However, consideration has been given to achieving strong infiltration properties.

Examples of the halogenated hydrocarbons include methylene chloride and monochlorobenzene, aromatic hydrocarbons include toluene and xylene, alcohols include methyl alcohol, ethyl alcohol, propyl alcohol, and various other alcohols, and ethers include methyl alcohol, ethyl alcohol, propyl alcohol, and other various alcohols. Cellosolve and other esters include vinegar ethyl and E! For ketones, methyl isobutyl ketone, cyclohexanone, etc. can be used.

In addition, examples of the above-mentioned organonrane compounds include paraaminophenyltrihydroxysilane, vinyltrichlorosiphon, allyltrichlorosilane, γ-glycidoxyprobyltrimethoxysilane, vinyltris(β-methoxyethoxy)silane, and vinyltriethoxysilane. Silane, β-(3,4 epoxycyclohexy/L/) ethyltrimethoxysilane, r-methacrylokikuprobi-trimethoxysilane, n-(dimethoxymethylsilylderrohyde 1v) ethylenediamine, n-(trimethoxysilylpropyl) ) Ethylenediamine, β-aminoethyltriacetoxysifun, etc. with the general formula R3iXm (However, in the formula R
is a vinyl group.

A V-Fun compound represented by a group containing an allyl group, an epoxy group, an acrylic group, an amine group, or a glycidyl group, where X represents an alkyl group, an alkoxyl group, an acetoxyl group, a hydroxyl group, or a halogen group, can generally be used.

Note that an anti-sagging agent may be mixed with the binder coat in the present invention. The anti-sagging agent has the effect of imparting both anti-sagging properties and liquid retention properties to the coating surface of the binder coat. As the anti-sagging agent, for example, colloidal silica powder is suitable, and the amount added is preferably 1 to 5%.

[Effect]

The binder coat configured as described above has the following effect to significantly improve the adhesive force between the three-dimensional network curing type coating film and the adhesion test terminal bonded thereon with an adhesive.

That is, when the above-mentioned binder coat is applied onto a three-dimensional network hardening type coating film that has already been completely cured, the mixed solvent in the binder coat quickly infiltrates and dissolves the surface of the coating film, activating the surface. become On the other hand, even if the coating film is completely cured, unreacted epoxy groups and polar groups such as unreacted or reaction-generated hydroxyl groups remain in the molecules. The groups are oriented on the surface of the coating film by the action of the mixed solvent, and then these react with one reactive group bonded to the silicon atom of the organosilane compound contained in the binder coat, forming a coating on the coating film and on it. The binder coat is chemically bonded to the binder coat. and,
Furthermore, on top of that and on both sides of the adhesion test terminal, apply an epoxy adhesive (a two-component adhesive, with an epoxy resin as the main ingredient).
epoxy resin or tar epoxy resin) 1001,
When a curing agent containing about 5 to 102 polyamines or about 1002 polyamides is applied and then glued together, the reactive groups in the organosilane compound that did not participate in the reaction with the coating film are removed. Furthermore, since the adhesive reacts with the reactive groups present in the adhesive and chemically bonds with each other, the coating film and the adhesive bond extremely strongly due to the crosslinking action of the organosilane compound in the binder coat. The adhesion between the adhesive and the adhesion test terminal was better than before, and there were no particular problems.

An example of this situation is shown below in terms of model structure. However, none of the atoms in the main chain are shown.

+ R8i'ICs Binder coat ↓ First, equation (1) shows that the cured resin formed by the reaction between the epoxy resin in the epoxy resin paint or the tar epoxy resin paint and the polyamine or polyamide reacts with the mixed solvent in the binder coat. This shows a state in which the resin molecules are highly activated and the hydroxyl groups in the resin molecules are oriented on the surface. Then, this hydroxyl group reacts with the organosilane compound in the binder coat and bonds to the silicon atom as shown in formula 12). Next, an epoxy resin adhesive is applied on both sides of the terminal for adhesion testing, and when the two are bonded together, the polyamine or polyamide blended in the adhesive binds to the epoxy groups and glycidyl groups in the organosilane compound molecules. , by ring-opening other reactive groups (3
) The coating film and the epoxy resin adhesive are firmly bonded together using the organosilane compound as a crosslinking molecule.

In addition, when an aminosilane compound is used as the organosilane compound, this amino group has the same effect as polyamine or polyamide in the curing reaction of the epoxy resin that is the paint, so in this case, there is a gap between the paint film and the aminosilane compound. In some cases, ring-opening polymerization as shown in formula 13) is carried out. In such cases, other reactive groups (for example, silanol groups, acetoxyl groups, etc.) bonded to the opposite side of the amino group of the aminosilane compound may interact with the hydroxyl group or epoxy group in the adhesive. react.

〔Example〕

The effects of the binder coat of the present invention will be explained using examples. Note that all "parts" in the examples are "parts by weight." In addition, the coating film and adhesion test terminal were lightly sprayed with vapor and further wiped lightly with a special solvent before being subjected to the test.

Figure 1 shows the adhesion test situation in the present invention.
1 is sxtw, 2 is a paint film, 5 is a binder coat, 4 is an epoxy adhesive (the main ingredient is F+'gin resin 100
t mixed with 100 t of polyamide as a hardening agent), 5 indicates the adhesion test terminal, and 6 indicates the direction of the tensile test.

Example 1 A tar epoxy coating film that had been immersed in natural hot seawater for 6 months after painting was pulled up, washed with water, and then dried. 1 A binder coat having the composition shown in Table 1 was applied using a spray V-.
1. Dry at room temperature for 4 hours. Next, an epoxy adhesive was further applied thereon, and the same adhesive was also applied to the adhesion test terminal, and then both were glued together and dried at room temperature for 24 hours.

Thereafter, the adhesion to the steel plate was measured by the adhesion method, and as shown in Table 2, the adhesion was good. For comparison, the adhesive force was measured by directly gluing the coating film and the adhesion test terminal together with epoxy adhesive in the same manner as above, without using the binder coat at full heat, and by otherwise treating the same as above. When measured in the same manner as above, as shown in Table 2, the adhesion was very poor. As can be seen from the peeling pattern shown in Table 2, this is due to the strong adhesion between the paint film and the adhesive in the case of the binder coat, which indicates cohesive failure of the paint film. On the other hand, in cases where a binder coat is not used, the adhesion between the paint film and the adhesive is weak, and the film peels off between them.

Table 1 Table 2 using a tensile speed of 5 so/min. Find the tensile adhesion force.

Example 2 After painting, a binder coat having the composition shown in Table 5 was applied by spraying onto the epoxy resin paint which had been exposed outdoors for 6 months, and was left to dry at room temperature for 4 hours. Next, an epoxy adhesive was applied thereon, and the same adhesive was applied to the adhesion test terminal at the same time, and then the two were glued together and dried at room temperature for 24 hours.

Thereafter, in the same manner as in Example 1, the adhesion force with the steel plate was measured by the adhesion method, and as shown in Table 4, the adhesion was good. For comparison, the coating film and the adhesion test terminal were directly glued together with epoxy adhesive in the same manner as above without using any binder coat, and the other things were treated in the same way as above, and the adhesion was measured. Measurements were made in the same manner as above, and as shown in Table 4, the adhesion was very poor.

Table 3 Table 4 Example 3 After painting, the tar epoxy coating film was immersed in seawater at 40°C for 3 months, then pulled up, washed with water, and dried.A binder coat with the composition shown in Table 5 was applied by spraying, and the film was left to stand at room temperature. It was dried for 4 hours. Next, an epoxy adhesive was applied thereon, and the same adhesive was applied to the adhesion test terminal at the same time, and then the two were glued together and dried at room temperature for 24 hours.

Thereafter, the adhesion force with the steel plate was measured by the adhesion method in the same manner as in Example 1, and as shown in Table 6, the adhesion force was good. For comparison, we did not use any binder coat at all, but the coating film and the adhesion test terminal were directly glued together with epoxy adhesive in the same way as above, and the other things were treated in the same way as above. When measured in the same manner as in Table 6, the adhesion was poor as shown in Table 6.

Table 5 Table 6 [Effects of the Invention] As described above, according to the present invention, when bonding the coating film and the adhesion test terminal with an epoxy adhesive in the coating film adhesion test, an organosilane compound is added to the mixed solvent. By applying the blended binder coat to the surface of Aoi Aoi in advance,
The adhesion between the coating surface, adhesive, and adhesion test terminal becomes stronger. Therefore, since the adhesive does not come off between the coating film surface and the adhesive during the adhesion test, the measurement accuracy of the coating film adhesion test can be improved.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the adhesion test situation according to the present invention. 1... Steel plate, 2- Paint film, 3... Binder coat, 4
...Epoxy adhesive, 5.Adhesion test terminal, 6.
・Tensile test direction

Claims (1)

[Claims] When measuring the adhesion between a completely cured three-dimensional reticulated coating film formed on the surface of a workpiece and the workpiece, halogenated hydrocarbons, aromatic hydrocarbons, alcohols, ethers, esters, or ketones are A mixed solvent containing two or more solvents selected from at least two groups among organic solvents belonging to Group 6, and a general formula RSiX_3 having two or more different reactive groups bonded to a silicon atom in one molecule. An organosilane compound represented by After applying a binder coat containing a halogen group) to the surface of the three-dimensional reticular curing type coating film, it is dried, and then the dried binder coat surface and the adhesion test terminal are glued together using an adhesive. A coating film adhesion test method comprising: measuring the adhesive force between the three-dimensional network-cured coating film and the object to be coated after the adhesive is cured.