JP4845242B2 - Primer composition and adhesion or coating method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a primer composition for surface treatment for improving adhesion and adhesion when an adherend is bonded or coated with a radical polymerization curable resin. In particular, the present invention relates to a primer composition suitable for metal surface treatment.
[0002]
[Prior art]
Acrylic monomers and oligomers, vinyl compounds such as unsaturated polyester and styrene, and radical polymerization curable resins based on polyene / polythiol are widely used in the fields of adhesives, paints, coating agents and potting agents. ing. The above radical polymerization curable resin is usually in the form of liquid or paste and is irradiated with active energy rays such as ultraviolet rays or electron beams, or a room temperature curable type using a redox polymerization initiator, or a heat curable type. Are known.
[0003]
It is known that by adding an acidic phosphate ester having an unsaturated double bond to these radical polymerization curable resins, adhesion and adhesion to metal are improved (Japanese Patent Laid-Open No. 54-141826). JP, 58-147477, and JP 59-84964).
[0004]
[Problems to be solved by the invention]
However, for example, when an adhesive composition in which only an acidic phosphate is added to a radical polymerization curable resin is used, the effect of improving the adhesiveness is not sufficient, and the physical properties of the cured resin (tensile strength, hardness, water resistance and Heat resistance, etc.), curing characteristics of the resin (such as curing rate and reaction rate) and storage stability may be reduced.
[0005]
In addition, it is already known that a primer in which an acidic phosphate is dissolved in a volatile solvent is used (see JP-A-1-297482 and JP-A-6-93211).
[0006]
However, since such a primer uses a volatile solvent, it has to wait for the solvent to evaporate, and there is a problem that ventilation equipment or the like is required in the work environment. In addition, due to recent environmental destruction problems, it is not preferable to release volatile solvents into the environment.
[0007]
The present invention has been made in view of the above points, and when attempting to bond or coat a metal using a radical polymerization curable resin, without reducing the performance of the radical polymerization curable resin, A primer composition that improves adhesion is provided.
[0008]
[Means for Solving the Problems]
That is, the present invention provides: a. And b. In a total of 100 parts by weight, the following a. 0.1-30 parts by weight and b. 7 99.9 and also contains a weight portion, characterized in that it does not contain a volatile solvent and water, a surface treatment primer composition of stainless steel and aluminum,
a. Acidic phosphate ester or salt thereof represented by the following formula:
b. Dicyclopentenyloxyethyl methacrylate An adherend which is formed by applying an adherend in advance with the primer composition when adhering or coating the adherend using a radically polymerizable resin. In this bonding or coating method, the adherend is stainless steel or aluminum.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described below.
[0010]
A. Used in the present invention a. An acidic phosphate ester or a salt thereof (hereinafter referred to as an acidic phosphate ester) is a monoester, a diester or a mixture of a monoester and a diester of phosphoric acid represented by the following general formula.
[0011]
[Chemical 3]
[0012]
a. As acid phosphooxyethyl methacrylate, (meth) acryloyloxypropyl acid phosphate, bis (2- (meth) acryloyloxyethyl) phosphate, acid phosphooxypolyethylene glycol (meth) acrylate, acid phosphooxypolypropylene glycol (meta ) Acrylate and amine salts thereof are preferable, but not limited thereto, and these may be used alone or in combination of two or more.
[0013]
a. Is used in a. And b. Is preferably 0.1 to 30 parts by weight, and more preferably 0.5 to 10 parts by weight. If it is less than 0.1 parts by weight, the adhesiveness and adhesion may be small. If it exceeds 30 parts by weight, the viscosity of the primer becomes high and it is difficult to use, and the physical properties of the radical polymerization curable resin are lowered. There is a possibility that the adhesion is small and economically undesirable.
[0014]
B. Used in the present invention. The acrylic monomer is an acrylic acid ester or a methacrylic acid ester (hereinafter referred to as (meth) acrylic acid ester), and is not particularly limited as long as it can dissolve or disperse the above-mentioned acidic phosphoric acid ester or a salt thereof. .
[0015]
b. As methyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, dicyclopentyl (meth) acrylate, dicyclopentenyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, methoxy Phenoxyethyl (meth) acrylate, methoxydiethylene glycol (meth) acrylate, trimethylolpropane tri (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, glycerol (meth) acrylate, glycerol di (meth) acrylate, 2-hydroxyethyl (meth) ) Acrylate, 2-hydroxypropyl (meth) acrylate, ethoxyethyl (meth) acrylate, polyethylene glycol (meth) acrylate, phenoxyethyl ( ) Acrylate, dicyclopentenyloxyethyl (meth) acrylate, phenoxydiethylene glycol (meth) acrylate, tripropylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 2,2-bis (4- (Meth) acryloxyphenyl) propane, 2,2-bis (4- (meth) acryloxyethoxyphenyl) propane, 2,2-bis (4- (meth) acryloxydiethoxyphenyl) propane, 2,2- Bis (4- (meth) acryloxypropoxyphenyl) propane, 2,2-bis (4- (meth) acryloxytetraethoxyphenyl) propane, trimethylolpropane tri (meth) acrylate, neopentyl glycol di (meth) acrylate , Pentaerythritol Examples include, but are not limited to, tiger (meth) acrylate, dipentaerythritol hexa (meth) acrylate, and KAYARAD R-684 (manufactured by Nippon Kayaku). These may be used alone or in combination of two or more. Can be used. Among these, those with less odor and low viscosity are preferable in terms of working environment.
[0016]
b. Is used in a. And b. Is preferably 70 to 99.9 parts by weight, more preferably 90 to 99.5 parts by weight. If the amount is less than 70 parts by weight, the primer has a high viscosity and is difficult to use, the physical properties of the radical polymerization curable resin are lowered, the adhesiveness and adhesion are small, and there is a possibility that it is not economically preferable. If it exceeds, the adhesiveness and adhesion may be small.
[0017]
The primer composition of the present invention does not contain a volatile solvent such as methyl alcohol, ethyl alcohol, isopropyl alcohol, ethyl acetate, acetone, methyl ethyl ketone, toluene, xylene, methylene chloride, chloroform, and 1,1,1-trichloroethane. preferable. Furthermore, it is preferable not to contain water. By not containing a volatile solvent or the like, there is no need to wait for volatilization of the solvent or the like, so that the working time is shortened and the influence on the human body and the like is eliminated.
[0018]
Various additives can be added to the primer composition of the present invention depending on the purpose. For example, when a primer composition is applied to a metal surface and then adhered or coated after a long time, a polymer that is soluble or dispersible in an acrylic monomer may be added.
[0019]
Examples of such polymers include polystyrene, polymethyl methacrylate, polyvinyl chloride, polyvinyl acetate and saponified products thereof, polyvinyl acetal, polyvinyl butyral, vinyl chloride-vinyl acetate copolymers and saponified products thereof, vinyl chloride-vinyl acetate- (Anhydrous) maleic acid copolymer and saponified product thereof, methyl methacrylate-styrene copolymer, methyl methacrylate- (meth) acrylic acid copolymer, and acidic phosphate ester which is a component of the present invention, methyl methacrylate, Examples include, but are not limited to, copolymers with vinyl monomers such as styrene, vinyl chloride and vinyl acetate.
[0020]
By adding these polymers to the primer composition, alteration of the acidic phosphate ester in the primer composition applied to the adherend surface, particularly the metal surface, and rusting of the metal surface can be prevented.
[0021]
As additives other than polymers, antioxidants, dyes and pigments for coloring, organic or inorganic fillers and the like can be used in order to improve the storage stability without impairing the object of the present invention.
[0022]
The adherend of the present invention is preferably used for metals such as stainless steel and aluminum.
[0023]
The primer composition of the present invention can be preferably used when performing adhesion or coating using an adhesive or coating containing a radical polymerization curable resin, particularly an acrylate monomer or oligomer, and more preferably when performing adhesion. It can be used.
[0024]
【Example】
Hereinafter, the present invention will be described in more detail with reference to examples.
As the adhesive, a two-component acrylic adhesive having a blending ratio shown in Table 1 was used.
[0025]
[Table 1]
[0026]
Moreover, as a test piece, stainless steel (SUS304, 100 mm × 25 mm × 0.3 mm) and aluminum (A5052P, 100 mm × 25 mm × 0.5 mm) were used.
[0027]
[Experimental Example 1]
A primer composition having the blending ratio shown in Table 2 was prepared. The primer composition was impregnated into a waste cloth, and the primer composition was applied to a test piece in a range of 100 mm × 25 mm in an environment of a temperature of 23 ° C. and a humidity of 50%. did.
Next, an equal amount of two-component acrylic adhesive is mixed, applied to the test piece, immediately bonded and fixed, and cured for 24 hours in an environment of a temperature of 23 ° C. and a humidity of 50%. A strip test was conducted. The results when stainless steel is used as the test piece are shown in Table 2, and the results when aluminum is used are shown in Table 3.
[0028]
(Measurement method for peel test)
The peel strength was measured in a T-shaped peel test according to JIS K-6854 (tensile speed 50 mm / min, unit kgf / 25 mm) in an environment of a temperature of 23 ° C. and a humidity of 30% to measure the peel strength.
After the test, the fracture state was observed. Moreover,% of a fracture state was shown by the ratio of the cohesive fracture part area per adhesion area.
[0029]
[Table 2]
[0030]
[Table 3]
[0031]
[Experiment 2]
Each component was mixed at the blending ratio shown in Table 4 to prepare each primer composition, and the same procedure as in Experimental Example 1 was performed except that aluminum was used as a test piece. The results are shown in Table 4.
[0032]
[Table 4]
[0033]
[Experiment 3]
The experiment was performed in the same manner as in Experimental Example 1 except that the primer composition having the blending ratio shown in Table 5 was used. The results in the case of stainless steel was used as the test pieces shown in Table 5, the results obtained by using the aluminum as shown in Table 5.
[0034]
[Table 5]
[0036]
【The invention's effect】
Since the primer composition of the present invention has extremely improved adhesion to a metal, more preferably stainless steel or aluminum, the industrial benefit thereof is extremely large.
In addition, since it is a solvent-free primer composition that does not require the use of volatile solvents, it is environmentally friendly, has no environmental impact, and does not require a drying process. Is extremely large.

Claims (2)

a. And b. In a total of 100 parts by weight, the following a. 0.1-30 parts by weight and b. A primer composition for surface treatment of stainless steel and aluminum, comprising 70 to 99.9 parts by weight and containing no volatile solvent and water.
a. Acidic phosphate ester represented by the following formula or a salt thereof
b. Dicyclopentenyloxyethyl methacrylate Using a radically polymerizable resin, upon adhering or coating the adherend is a stainless steel or aluminum, deposition, characterized by comprising precoated the adherend with a primer composition of claim 1, wherein Body adhesion or coating method.