JPH02117967A - Primer - Google Patents

Abstract

PURPOSE:To provide a primer consisting of an organozirconium compound and suitably used in carrying out adhesion of a nonpolar or high-crystalline resin, coating, printing, etc., of the above-mentioned resin using alpha-cyanoacrylate. CONSTITUTION:An objective primer consisting of an organozirconium compound (preferably zirconium acetylacetonate) and suitably used in application of alpha- cyanoacrylate to a nonpolar or high-crystalline resin.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a primer (undercoating agent) used when adhering non-polar or highly crystallized resins or coating or printing Fi resins using α-cyanoacrylate.
It is related to.

The purpose of the present invention is to use α-cyanoacrylate to successfully adhere materials such as non-polar or highly crystallized resins, which have conventionally been difficult to adhere, paint, or print, or to improve the adhesiveness of such materials. Good painting or printing etc.
The purpose of this invention is to provide primers that can be used for

Non-polar or highly crystallized resins, such as polyolefins such as polyethylene, polypropylene, polybutene, and polyfluoroethylene, polyethylene terephthalate, polyacetal, and nylon, as well as plasticizers, are blended in long lengths into soft/J (PVC films). are materials that are difficult to adhere, paint, and print on, and it is not possible to adhere these resins well or apply paint or prints on these resin surfaces using normal methods. be.

Conventionally, in order to improve the adhesive properties of these materials, for example, polyethylene and polypropylene are subjected to oxidation treatments such as flame treatment, corona discharge treatment, radiation treatment, and dichromate or sulfate treatment to remove polarity such as carbonyl groups. Surface treatment methods have been proposed to generate groups on the surfaces of these materials.

Special chemical treatments such as lithium paper treatment, alkaline heat treatment in a helium stream, and treatment of metallic sodium with ammonia solution have been proposed for resins such as polyfluoroethylene that cannot be surface oxidized.

However, these treatment methods require special equipment, are complicated to work with, cannot uniformly treat objects with complex shapes, and are expensive. be.

There are also many suggestions regarding primers.
Japanese Patent Publication No. 52-98062. According to No. 56-141328 and No. 57-119929, a primer is proposed in which chlorinated polyethylene, chlorinated polypropylene, or fatty acid-modified acrylated alkyd resin is dissolved in an organic solvent.

However, according to JP-A-58-8734, these primers have good adhesion to polyolefin but poor adhesion to the main top coat, or show good adhesion to the top coat and polyolefin. Even so, it has been pointed out that there is a drawback that inter-film adhesion deteriorates due to repeated cooling and heating cycles.

Also, JP-A-54-124048. Same 124049゜ Same 1
According to 24095, solid rubber on a polyolefin base material,
We are proposing a modified polyolefin containing an unsaturated carboxylic acid or its derivative and a radical generator, but 1%
According to JP-A No. 7-38827, unreacted unsaturated carboxylic acids, radical generators, etc. remain in these methods and have an undesirable effect on the adhesion of the coating film.

Furthermore, JP-A-54-124050, JP-A-55-34270,
According to 55-84271, propylene/styrene/
An improved resin containing a butadiene block copolymer and an inorganic filler as essential components has been proposed, but even with this method, drawbacks such as poor weather resistance in non-coated areas and low temperature brittleness due to the filler formulation have been pointed out. It seems that there are various problems such as If non-polar or highly crystallized resins such as polyolefins are properly adhered or painted or printed on the surface of these resins, it is possible to utilize the excellent physical properties of polyolefins, reduce weight as a substitute for metal materials, and provide non-rusting properties. It has many advantages such as cost reduction and cost reduction, and its contribution to various fields such as the automobile industry and the electrical equipment industry is considered to be significant.

In view of these circumstances, the present inventors have made extensive research efforts to develop a surface treatment method that is simple and speedy compared to these conventional techniques. They developed a primer that made printing possible, and thus completed the present invention.

That is, the present invention relates to a primer made of an organic zirconium compound for applying α-cyanoacrylate to a non-polar or highly crystallized resin trap.

In the present invention, applying α-cyanoacrylate to non-polar or highly crystallized resins means using α-cyanoacrylate to adhere those resins, or applying α-cyanoacrylate (mainly a hardened film) to those resins. It means use as an undercoat for paint or printing ink in painting or printing.

The primer Vi of the present invention is a book consisting of an organic zirconium compound, and the organic zirconium compound is a compound 1 in which an organic group and zirconium are bonded, and it can be used in the present invention regardless of its type, structure, etc.

As an organic group in organic zirconium compounds.

Examples include alkyl, alkenyl, alkoxy, aryl, acetylacetonyl, acetyloxy, cyclohexyl, etc. #fVc C,
The above hydrocarbon groups are preferred.

Specific examples of organic zirconium compounds include acetylacetone zirconium, trifluoroacetylacetone zirconium, naphthenate zirconium, octylate zirconium, etc., and acetylacetone zirconium has excellent effects and is a preferred compound for the present invention.

The primer made of the organic zirconium compound of the present invention is used by applying α-cyanoacrylate when adhering non-polar or highly crystallized resin, or when painting or printing the resin. However, as will be described later, it is desirable to control the coating thickness during use in order to fully exhibit the effects of the present invention, and therefore it is desirable to use it as a solution.

The organic solvent used for making the solution is a general organic solvent that can completely dissolve or disperse the organic zirconium compound and has appropriate volatility.
It is also desirable that it be easily available industrially.

In addition, the solvent is preferably one that can sufficiently wet the surface of the resin such as polyolefin in order to make the primer work more efficiently, and for this purpose, the surface tension of the organic solvent must be equal to the critical surface tension γ It is more desirable to select and use a smaller one. The following table shows typical values of surface tension and critical surface tension that can be used as a reference when selecting the solvent to be used.

The concentration of the organic zirconium compound when it is made into a solution is o
, ooi to 10% by weight.

As will be described later, the organic zirconium compound applied to the surface of the base material can best exhibit the desired effect of the present invention when it is applied to a thickness close to that of a monomolecular film. If the concentration is 0.001%, it will be easier to achieve the purpose, and as the concentration increases, the film of the organic zirconium compound will become thicker in proportion to it, and if it becomes too thick, the layer will become a fragile layer. It is.

The α-cyanoacrylate in the present invention is represented by the following general formula.

R in the above formula includes alkyl, alkenyl, cyclohexyl, aryl, and alkoxyalkyl groups, and specifically includes methyl, ethyl, n-propyl, n-
Examples include butyl, isobutyl, n-pentyl, allyl, cyclohexyl, benzyl, and methoxyglobyl groups.

These α-cyanoacrylates are the main components of commercially available cyanoacrylate-based instant adhesives, and in the present invention, these commercially available adhesives are directly used as α-cyanoacrylates. You can also use

Commercially available cyanoacrylate adhesives use α-cyanoacrylate as a paste, and are made into adhesives by blending various components as shown below, for example, as desired.

(1) Stabilizers (2) Thickeners (3) Modifiers (4) Coloring agents, etc. Stabilizers are used to improve the storage stability of anoacrylate adhesives and usually prevent anion from forming. Sulfur dioxide, aromatic sulfonic acids, sultones, etc. are used as agents, and hydroquinone, hydroquinone, etc. are used as radical polymerization inhibitors.
Hydroquinone monomethyl ether is used.

Since α-cyanoacrylate, which is the base material, is originally a low-viscosity liquid with a few centimeter voids, thickeners are used to thicken this into a viscous liquid with tens to thousands of centimeter voids depending on the application. For example, it is used by dissolving polymethyl methacrylate, acrylic rubber, cellulose rust conductor, etc.

Modifiers are blended to improve the impact resistance, heat resistance, etc., which are disadvantages of cyanoacrylate adhesives.
Maleic anhydride and its derivatives shown in Japanese Patent No. 12737 are used.

In addition, in order to make it possible to bond porous wood materials containing acidic sap, which have traditionally been considered difficult to bond, a crown compound as disclosed in Japanese Patent Publication No. 55-2238 has been used. be.

Furthermore, in order to impart flexibility to the adhesive layer after curing, tricresyl phosphate, dioctyl phthalate, dimethyl sepacate, or the like may be added as a plasticizer.

Coloring agents are used to color adhesives in order to make it easier to identify adhesive locations.
In some cases, acid salts of basic dyes shown in the above publication are blended.

In addition, for the purpose of imparting fragrance to adhesives, for example, JP-A-53
The ester fat conductor flavor shown in Japanese Patent No. 58541 may be added.

Further, in the present invention, α-77 noacrylate diluted with a specific organic solvent can also be used. Suitable organic solvents include toluene, butyl acetate, or methyl chloroform, which are compatible with α-cyanoacrylate and do not impair stability, and these solvents do not contain water or other impurities. is preferred.

When using the primer of the present invention for adhering non-polar or highly crystallized resins, the application method is as follows: When adhering a combination of non-polar or highly crystallized resin materials as adherends, both of them may be used. When the surface is also non-polar or a combination of a highly crystallized resin and a polar material, it is possible to immerse only the former surface in a primer solution for a few seconds, apply it with a brush, spray it, etc., and apply the primer in this way. By air-drying the adherend and removing the solvent, α
- The adherend can be made to adhere well with cyanoacrylate.

The adherend made of non-polar or highly crystalline F'B resin is thus coated with the primer of the present invention.

The adhesive is bonded by conventional means using α-cyanoacrylate, and the resulting bonded body has excellent adhesive strength.

Other methods include coating the surface of the adherend with a mixture of α-cyanoacrylate and an organic zirconium compound, or diluting a solution with an organic solvent if necessary, or using a two-liquid discharge type coating machine. It is also possible to adopt a method of simultaneously discharging a solution of α-cyanoacrylate and an organic zirconium compound to apply and bond the primer and adhesive at the same time. However, when using the mixing method, it is important to avoid moisture when handling α-cyanoacrylate as it has the unique property of exhibiting strong anionic activity.

Care must be taken to avoid contamination with foreign substances such as amines and alcohols.

For painting or printing on non-polar or highly crystallized A1 fat,
By applying a primer using the method described above on the base material surface made of these resins, and applying α-cyanoacrylate on top of the primer to form a film of the polymer, the base material becomes suitable for painting and printing. A substrate whose surface is coated or printed by conventional means is a good base material, and a substrate coated or printed with excellent performance, i.e., a non-polar or highly crystallized resin, is a relubric material. be.

The method of applying the primer of the present invention when painting or printing is adhesion and between the lines, but the excellent effects in painting or printing can be obtained even more by taking the following steps. The process described below is the preferred method for painting or printing.

First, as a first step, a primer prepared by dissolving an organic zirconium compound in an organic solvent is applied to the surface of the base material to be painted or printed.

The above primer can be applied to the surface of the substrate by the usual brushing, dipping, or spraying methods, and the open time after treatment is usually 5 to 50 minutes at room temperature.
It usually takes 60 minutes, but it can take several days depending on the work process.

As a second step, α-cyanoacrylate is applied onto the substrate coated with the primer to form a film of α-cyanoacrylate polymer.

Is there a method for applying α-cyanoacrylate? 5! This can be carried out by a dipping method, a spray method, or the like.

However, when using the spray method, it is preferable to use a diluted solution of α-cyanoacrylate in an organic solvent to prevent problems with nozzle clogging.

Furthermore, when using a commercially available/anoacrylate adhesive as α-cyanoacrylate, it is preferable to use one that is commercially available as a low viscosity grade.

The substrate coated with α-cyanoacrylate is 12
Leave to stand for a period of time to form a thin layer of α-cyanoacrylate polymer on its surface.

Although the film thickness of the α-cyanoacrylate polymer is not particularly limited, it is preferably about 10 to 50 μm so as to avoid glue gaps.

By the method described above, the base material coated with the primer and α-cyanoacrylate is coated with a general paint or printed with a printing ink.

There are various types of paints and printing inks, and there are various classification methods, but the following can be classified according to the vehicle resin acid fraction.

Rosin derivatives, nitrocellulose resins, vinyl resins, acrylic resins, polyester resins, polyamide resins, polyurethane resins, phenolic resins, ebony resins, aminoalkyd resins, melamine resins,
UV-curable acrylic oligomers and the like can be used in the present invention, but the following are more suitable for use in polyolefins:
Particularly preferred are paints or printing inks based on polyurethane resins, EBOKI 7 resins, alkyd resins, and the like.

Furthermore, since there is a limit to the heat resistance of the base resin, especially polyolefin, the baking paint preferably has a baking temperature of 90° C. or lower.

The paint application method is brush application method or bar coater method.

It can be carried out by a conventional method such as a roller method or a spray method, and one printing method can be carried out by a conventional method such as a silk screen printing method, a gravure printing method or a flexographic printing method.

The primer made of the organic zirconium compound of the present invention can be adhered to non-polar or highly crystallized resin using α-cyanoacrylate, or painted or printed on the resin using α-cyanoacrylate and paint or printing ink, etc. Although the reason for improving the ability of organic zirconium is unknown, as shown in the table below, it depends on the type of organic zirconium compound, but when applied very thinly, i.e. 0.0
The effect is most noticeable when 01 to 1f//rrl is applied.

However, this mark indicates base metal failure.

The values in the above table are based on a polypropylene plate (2 m thick) as the adherend, zirconium acetylacetonate (used as a methyl chloroform solution of various concentrations) as the primer, and an α-cyanoacrylate adhesive (alonoalua analyte) as the adhesive. 201: Toagosei Kagaku Kogyo ■!!! trade name) was used for adhesion, and at that time, differences in the expression of tensile shear strength of the bonded portion due to differences in the amount of primer applied were determined.

The adhesive body Fi was cured for one day under the conditions of 23° C. and 60% PH.

From the above results, it was found that the primer is most effective when applied in a state close to a monomolecular layer. It is estimated that the effect of the book is expressed by the following mechanism.

That is, the organic zirconium compound of the present invention.

It exists in a state close to a monomolecular film between the nonpolar or highly crystallized resin surface and the α-cyanoacrylate layer (monomer or hardened polymer film layer), and the groups with high affinity for the resin layer and α- It is presumed that it has a high affinity with the cyanoacrylate layer, in other words, the lipophilic groups and polar groups are arranged in an orderly manner, and acts as a binder between the resin layer and the α-cyanoacrylate layer to exert the effects of the present invention. .

Therefore, in order to better express the effects of the present invention, K
The organic zirconium compound to be used, its degree, amount of application, etc. are determined by considering the combination of zirconium and organic group constituting the organic zirconium compound, that is, the type of organic zirconium compound, and the material of the adherend or base material. must be determined. Regarding the coating amount, as shown in the table above, if it is too small and the primer layer cannot completely cover the surface to be bonded, painted or printed, it is natural that good results will not be obtained. There was so much N that the primer layer far exceeded the monomolecular layer.
When the layer reaches 0.001 to 1, the layer itself becomes a fragile layer and the effect of the present invention is no longer expressed.
1/lrj or more preferably α01 to 0.111/m
It is preferable for the present invention to apply the coating in such a manner that it becomes '.

By strongly bonding the non-polar or highly crystallized resin and α-cyanoacrylate through the organic zirconium compound, the adhesion of the resin is strengthened by α-cyanoacrylate, and a film of α-cyanoacrylate polymer is formed. is firmly adhered to the surface of the resin, and conventionally -
Painting or printing can be applied easily and without any problems using the paints and printing inks used for boat fishing.

The excellent effects obtained by the present invention are due to the combination of α-cyanoacrylate, organic zirconium compound, and non-polar or highly crystallized resin.

This was achieved for the first time, and organic titanium compounds had previously been considered as a primer or base treatment when bonding polyolefins such as polyethylene, but in such cases, epoxy-based adhesives,
Since urethane-based, rubber-based, acrylic-based adhesives, etc. were used, excellent effects were not observed, and the effects of the present invention cannot be predicted from these results, and the effects produced by the present invention cannot be predicted by those skilled in the art. It is so good that it cannot be predicted.

Furthermore, as a matter of course, one of the effects aimed at by the present invention is as follows:
Other substrates are only expressed when the substrate is a non-polar or highly crystallized resin.

In other words, it does not appear in metal, wood, ceramics, etc.

The present invention is effective for non-polar or highly crystallized resins such as polyethylene terephthalate, polyacetal, nylon, etc., and is particularly effective for polyolefins. Next, the present invention will be explained in more detail with reference to Examples and Comparative Examples.

Example 1. Comparative Example 1 The following materials were used as the Brimer 1 adherend and α-cyanoacrylate.

1. Brimer +11 acetylacetone zirconium +2+) IJ
Zirconium fluoroacetylacetonate (3) Zirconium naphthenate 0.2 I of each of the above compounds was dissolved in 998 g of toluene to prepare a brimer solution.

2. Adherent material (11 polyethylene plate (25X100X2m)
(21 polypropylene 7 plates (25X100X2m)
(3) Polyb template (25×1oo×2
■) 3. α-Cyanoacrylate Aron Alpha ◆201 (Cyanoacrylate adhesive; Toagosei Chemical Industry ■Product name) Brush the above Brimer solution on both sides of the test piece and let it air dry for about 10 minutes, then apply it to one side. α-cyanoacrylate was applied to the sample, both sides were put together, a pressing load of Q, 1 pf/cd was applied, and the sample was cured for 24 hours.

The tensile shear adhesive strength was measured using a Strograph W type tester at a tensile rate of 20/20 cm in accordance with JISI1861-1977.
= Measured.

As a comparative example, the adhesive strength was measured in the same manner as in Example 1 except that the adhesive was bonded without using a brimer.

Table 1 Polyolefin Adhesion Qin Seal Base material fracture tensile shear adhesive strength is the average value of three test pieces.

Example 2゜0.3 g of zirconium octylate was dissolved in methyl chloroform 997I to make a primer solution, and the adherends were polyacetal plate, polyurethane plate, and EP.
α- using T plate (each size 25x100x3m)
As the cyanoacrylate, Aron Alpha $221 (cyanoacrylate adhesive, trade name manufactured by Futaba Agosei Kagaku Kogyo ■) was used to adhere and stir in the same manner as in Example 1. Furthermore, as Comparative Example 2, a sample without using a primer was also bonded in the same manner.

Claims (1)

[Claims] 1. A primer consisting of an organic zirconium compound for applying α-cyanoacrylate to a nonpolar or highly crystallized resin.