CH686018B5 - primer compositions for the pretreatment of coatings and methods for treating them. - Google Patents

Description

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Description

The present invention relates to a primer composition which has excellent bondability to polyethylene, polypropylene and synthetic rubbers, and which readily binds to functional coatings such that it forms on the surface of these materials, by coating etc., a composite layer having an addition function, and a method of heat treatment by far infrared rays therefor.

The characteristic of the present invention consists in the production of a composition suitable for uses in which a polymer, an unsaturated di-carboxylic acid and a polyolefin or its product denatured by chlorine, is used as the main component, and applies chlorosulfonated polyethylene to improve heat resistance.

Summary of the invention

The present invention is a primer which can be designed not only to improve the appearance of polyolefins such as polyethylene or rubbers by coloring them, but also to considerably improve durability by an ultraviolet filtering effect, to prevent the oxidation deterioration of synthetic rubbers caused by oxygen or ozone, contamination or odor generation of synthetic rubbers, and also improve their abrasion resistance. In addition, unlike the black coloring of conventional polyethylene and rubber intended to maintain their weather resistance, colored aspects can be imparted to polyethylene and rubber without lowering their weather resistance, and the heat resistance, Resistance to gasoline and resistance to chemicals in the primer itself can be improved.

Polyethylene includes polymers such as low density polyethylene (LDPE), and high density polyethylene (HDPE) as well as ultra high density polyethylene. The rubber includes for example natural rubbers (NR), butadiene rubber (BR), styrene-butadiene rubber (SBR), acrylonitrile rubber (NBR), ethylene-propylene rubber (EPT), rubber of chloroprene (CR), butyl rubber (IIR), urethane rubber and chlorosulfonated polyethylene rubber (CSM) (except silicone rubber).

Basis of the invention

Polyethylenes have so far been developed as inexpensive engineering plastics such as a high strength product, a super high molecular weight product, etc. although it was impossible to cover or print them directly with paints or inks due to their lack of polarity and extreme inertia, and therefore it was difficult to widen their scope despite their high performance and low cost.

High density polyethylene has so far been used in a wide range of applications due to its excellent physical properties and low cost. However, high density polyethylene is rapidly crystallized by ultraviolet rays and it is deteriorated by cracking, so that it is not suitable for outdoor use.

That is why we have put on the market polyethylenes reinforced with carbon or an anti-aging agent, but the power of carbon or of anti-aging agent is limited and a product having a black appearance has limited uses. Consequently, a technique has been sought for coating polyethylene products with a view to obtaining an effective means not only for improving the appearance of the articles with a decorative finish, but also for considerably improving the durability on the outside by filtering the ultraviolet rays.

However, polyethylene has an absolutely non-polar molecular structure and it has no surface activity so that it cannot be coated without special surface treatments.

As the surface treatment method which has been used most generally up to now, there will be mentioned a method in which the surface layer is oxidized by a flame, an arc or a strong oxidizing agent, then coated with a finishing layer. .

However, such a treatment method is not suitable for practical use, since it is a process which makes it difficult to maintain constant adhesion due to an irregular treatment state, and which is dangerous due to its high toxicity . As with liquid primers for bonding polyethylene, the effectiveness of primers such as those of the Paminosilane type, organic titanium, organic aluminum etc. is well known, but these primers are sensitive to humidity (and they react quickly with humidity) and it is necessary to apply a finishing coat (or an organic cyanacrylate adhesive) on them (or (apply an adhesive) in a very short time of a few minutes, so that they cannot be applied at all on a large surface as in the case of paints.

In addition, rubber also requires other properties which are a function of the portions or of the time to be applied with the use of stretchability as an elastomer. Regarding syn3 rubbers

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There are various rubbers of the heat-resistant type, the oil-resistant type, the weather-resistant type, an energy-saving type, a highly functional special type, etc. which meets these requirements. In particular, the basic requirements for automobile tires are long-term safety and durability, and the molecules of butadiene rubber, styrene-butadiene rubber, isoprene rubber and rubbers natural have been respectively designed according to the requirements imposed on tires.

This means that one chooses a rubber from natural rubbers and the variety of synthetic rubbers, that one incorporates there additives such as a vulcanizing agent, a vulcanization accelerator, an anti-aging agent, a reinforcing agent , a filler and a plasticizer taking into account their combination. For example, to improve weather resistance, a rubber having fewer unsatisfactory connections is chosen, and to those having a lower vulcanizability, a third component is added. To improve weather resistance, carbon black can be added as a reinforcing agent.

However, these properties can be opposed to each other and often have to be compromised.

Most synthetic rubbers have inherently unsaturated bonds and therefore pose essentially problems of weather resistance, ozone resistance etc. Therefore, these problems cannot be solved completely by the design of the material mixture. The solution of the mixture will always cause secondary defects. For example, the color of the material is limited to black by the addition of carbon black, and such a limitation is not desirable in a colored fashion as are the various lifestyles of today.

Detailed description of the invention.

The object of the present invention is to solve the problems of rubber which are opposed to each other and the difficulty of the pretreatment of polyethylene by providing a primer which has good adhesion to both polyethylene, polypropylene and synthetic rubbers and functional coatings to perform functions such as weather resistance, ozone resistance etc. which relate only to the surface layer with a coating having these functions, to thereby achieve the development of a new article comprising composite materials of polyethylene, polypropylene, and synthetic rubber and a resin.

The first characteristic of the present invention comprises at least one polymer chosen from a grafted polymer (hereinafter referred to as grafted EVA), an unsaturated dicarboxylic acid and an ethylene-vinyl acetate copolymer (hereinafter designated by "EVA"), a grafted polymer (hereinafter referred to as grafted EEA) of an unsaturated dicarboxylic acid and an ethylene-ethyl acrylate copolymer (hereinafter referred to as ("EEA") or a product obtained by substitution of chlorine in the grafted polymer, a chlorinated polypropylene in which a grafted polymer of an unsaturated dicarboxylic acid and of polypropylene is subjected to a substitution of chlorine (hereinafter referred to as grafted chlorinated polypropylene), and a solvent.

A first comparative example of the first characteristic of the present invention consists of a primer composition which comprises:

an EVA grafted approximately 1 to 30 parts by weight a pigment approximately 0 to 30 parts by weight a solvent approximately 40 to 99 parts by weight and an organic titanium compound approximately 0 to 5 parts by weight the total being equal to 100 parts

Thus, the comparative primer comprises a grafted polymer of an ethylene-vinyl acetate copolymer soluble in a solvent and having excellent adhesion to polyethylene, polypropylene and rubber, an unsaturated dicarboxylic acid such as maleic anhydride etc. and a solvent, and a pigment or an organic titanium compound can be added to the primary if desired.

Even if such a pigment or an organic titanium compound is not incorporated, satisfactory adhesion to the polyethylene can be obtained.

By using only EVA, the adhesiveness of the hot melt to polyethylene or the adhesion of a topcoat can be achieved to some extent by adjusting the concentration or molecular weight of the vinyl acetate. If the concentration of the polyethylene component is high in the EVA, the adhesiveness of the hot melt of the EVA to the polyethylene is good while the adhesion of the topcoat is lowered. On the contrary, if the concentration of the vinyl acetate component of the EVA is high, the adhesion of the top coat is good, while the adhesiveness of the hot melt to polyethylene is lowered.

In other words, the mutual proportions of polyethylene and vinyl acetate in EVA exert opposite effects on the adhesiveness of the hot melt and on the adhesion of the top coat to polyethylene, and therefore, one cannot expect to obtain satisfactory results using only EVA.

The grafted polymer of an EVA and an unsaturated dicarboxylic acid such as maleic anhydride etc. in accordance with the present invention represented by the general formula:

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CH 686 018G A3

R \

X

(I)

R

/

n in which R represents an EVA and X represents an unsaturated dicarboxylic acid, is used because the use of the grafted polymer gives good adhesion of the finishing layer even if one obtains an EVA having a relatively low concentration of acetate of vinyl (and therefore a high concentration of polyethylene component) and good adhesion of the hot melt to polyethylene, and due to the high concentration of polyethylene component in the grafted polymer.

If the grafted polymer is made as described above, the effect conferring the polarity of the unsaturated dicarboxylic acid can be expected. Even if an EVA having a relatively low concentration of vinyl acetate is used, good adhesion of the topcoat is obtained and good adhesion of a polyethylene melt can be ensured. As with rubber, good adhesiveness can also be ensured by adjusting the solubility parameter (SP) of the grafted polymer to a value close to that of rubber.

The first characteristic of the first invention is a concentration of primer in the liquid state of such a grafted polymer of EVA and unsaturated dicarboxylic acid dissolved in a solvent.

The graft polymer used in the present invention preferably has a weight average molecular weight of 1 to 2 x 105 and a vinyl acetate content of 15 to 35%.

The amount of the graft polymer to be incorporated is in the range of I to 30 parts. The reason is that if the quantity is less than 1 part, it does not fulfill the function of primary, and if it exceeds 30 parts, it is not in the liquid state. When a trace of an organic titanium compound is used in a primer, the acetyl groups or the carbonyl groups of the grafted polymer of EVA and the unsaturated dicarboxylic acid are crosslinked with the organic titanium compound to give a film having higher hardness. In addition, the pigment and the surface of the polyethylene in the primer composition are only crosslinked in a small proportion by the organic titanium compound to give a higher polyethylene adhesiveness than that observed in the case where use is not made. not such a titanium compound. However, if the amount of the organic titanium compound exceeds 5 parts, the moisture sensitivity of the primer composition becomes high, which adversely affects it.

The pigment for the primer is used to color and slightly increase the resistance of the film, and a pigment having a coloring capacity and a diluting pigment having no coloring capacity are used in combination, which does not will not pose a problem unless a particular limitation is imposed on the nature of the pigments, the color, etc.

The solvent for the primary is preferably toluene or xylene. Benzene, tetrahydrofuran or triclene can also be used as a solvent, but they are not suitable for primary because of their high toxicity and the irritation they cause.

The first embodiment of the first characteristic of the present invention consists of a primer composition which comprises:

an EVA grafted approximately 2 to 30 parts a chlorinated polypropylene grafted approximately 0.5 to 25 parts a pigment approximately 0 to 30 parts, and a solvent approximately 40 to 97.5 parts the total being 100 parts.

This composition aims to improve the physical properties of the film and its adhesion to a top coat.

The grafted chlorinated polypropylene preferably has a weight average molecular weight of 6 to 10 x 104 and a chlorine content in the range of 20 to 30%.

This constitution is represented as a resin constituent corresponding to the general formula:

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X

(II)

\ J

n in which R 'represents a chlorinated polypropylene, and X represents an unsaturated dicarboxylic acid. The grafted chlorinated polypropylene or the chlorinated polypropylene represented by the general formula:

in which there is 0.3 to 0.8, are incorporated so as to improve the strength of the film and its adhesion to the finishing layer and to allow bonding to polypropylene. The amount of EVA grafted is in the range of 2 to 30 parts. The reason is that if the amount of grafted EVA is less than 2 parts, one cannot expect a bond to polyethylene in the case of increasing the amount of grafted chlorinated polypropylene or simply chlorinated polypropylene to be incorporated, and if it exceeds 30 parts, the composition is not obtained in liquid form.

The amount of the grafted chlorinated polypropylene to be incorporated is in the range of about 0.5 to 25 parts. The reason for this is that when the amount is in a range of less than 0.5 part, one cannot expect an improvement in the film strength and the adhesion of the top coat, and only when exceeds 25 parts, the composition cannot be supplied in liquid form due to the increase in the load of the grafted chlorinated polypropylene and of the grafted EVA to prevent the loss of adhesion to polyethylene or to rubber by increasing the amount grafted EVA to incorporate.

A second comparative example of the first characteristic of the present invention consists of a primer composition which comprises:

a grafted EEA or a product obtained by substitution of the grafted polymer with chlorine:

about 1 to 40 parts a pigment about 0 to 30 parts, and a solvent about 40 to 99 parts,

the total being 100 parts.

The grafted EAE preferably has a weight average molecular weight of 5 to 15 x 104 and an ethyl acrylate content in the range of 15% or less.

The product obtained by substitution of the grafted polymer with chlorine preferably has a chlorine content of 10 to 25%.

This constitution is represented as a resin constituent corresponding to the general formula:

in which R "represents a chlorinated EEA or an EEA, and X represents an unsaturated dicarboxylic acid. The reason for using the substitution product with chlorine of the grafted polymer is that a good adhesion of the finishing layer is obtained using this grafted polymer even in the case of an EEA having a relatively low concentration of ethyl acrylate (and a high concentration of the polyethylene component) and that good adhesiveness of the hot melt to polyethylene is obtained. due to the high concentration of the polyethylene component in the grafted polymer.

By constituting the grafted EEA as described above, one can expect to obtain the effect conferring the polarity of the unsaturated dicarboxylic acid. In addition, the good adhesion of the hot melt to polyethylene is obtained even in the case of an EEA having a relatively low concentration of ethyl acrylate and the good adhesiveness of the hot melt to polyethylene can also be preserved. Likewise, good adhesion to rubber can be maintained, because the

[C3H6-yCls] n

(III)

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solubility parameter (SP) of the grafted polymer or of the substitution product by chlorine of the grafted polymer is close to that of rubber.

The grafted EEA produces a more flexible film than that obtained from the grafted EVA and thus acts more effectively as a primer for rubber.

In such a constitution, if the amount of grafted EEA or chlorine substitution product of the grafted EEA to be incorporated is less than 1 part, film formation is difficult to obtain and therefore the function of primary is not met. On the other hand if its quantity exceeds 40 parts, the composition cannot be obtained in the form of a liquid.

The second embodiment of the first characteristic of the present invention comprises: a grafted EEA or a product obtained by substitution of the grafted polymer with chlorine: approximately 2 to 40 parts,

a chlorinated polypropylene grafted approximately 0.5 to 15 parts,

a pigment about 0 to 30 parts, and a solvent about 40 to 97.5 parts the total being 100 parts.

This constitution is characterized in that the grafted chlorinated polypropylene is incorporated to improve the strength of the film and the adhesion of a finishing layer and to make possible the bond to the polypropylene.

The amount of the grafted polypropylene to be incorporated is in the range of 0.5 to 15 parts. The reason is that if the amount of grafted EVA is less than 0.5 part, one cannot expect an improvement in film strength and adhesion of the topcoat. If the amount exceeds 15 parts, the adhesiveness to the rubber is lost, unless the amount of the grafted EAE or its substitute by chlorine is increased, and if the amount is increased, the amount of the resins in the composition becomes too high to give a composition in liquid form.

If the mixing rate of the grafted EEA or of its substitute product with chlorine is less than 2 parts, the amount of grafted chlorinated polypropylene to be incorporated is increased until the adhesiveness to rubber disappears. If the level exceeds 40 parts, the composition is not obtained in the form of a liquid.

The third embodiment of the first characteristic of the present invention consists of a primer composition which comprises:

an EVA grafted approximately 1 to 30 parts,

a grafted EEA or a substitution product with chlorine of the grafted polymer: approximately 1 to 29.5 parts, a chlorinated polypropylene grafted approximately 0.5 to 15 parts,

a pigment approximately 0 to 30 parts, and a solvent approximately 40 to 97.5 parts,

the total being 100 parts,

This constitution is characterized in that the grafted chlorinated polypropylene is incorporated to improve the resistance of the film and the adhesiveness to the finishing layer and to allow the bonding to the polypropylene, the grafted EEA or the substitution product by chlorine of the polymer. graft is incorporated to improve the follow-up capacity for rubber, and EVA is incorporated to allow better bonding to polyethylene.

The amount of EVA grafted is in the range of 1 to 30 parts. The reason is that if it is less than 1 part, one cannot expect adhesiveness to polyethylene and if it exceeds 30 parts, the composition is not obtained in the liquid state.

If the amount of grafted EEA or its chlorine product to be incorporated is less than 1 part, we cannot expect a follow-up capacity for rubber and if it exceeds 29.5 parts, the amount of grafted chlorinated polypropylene to be incorporated (the mixture of grafted EVA and grafted EEA or its chlorinated product and grafted chlorinated polypropylene cannot be maintained at an appropriate level.

The mixing rate of the grafted chlorinated polypropylene is in the range of 0.5 to 15 parts. The reason is that if the rate is less than 0.5 parts, the film strength and adhesion to the topcoat will not be improved and that if more than 15 parts, the amount of EVA grafted and grafted EEA or its chlorine product to be incorporated cannot be maintained at an appropriate level, and therefore the adhesiveness to rubber is lost.

The second characteristic of the present invention consists in that the composition comprises at least one polymer chosen from a grafted EVA, a grafted EEA or a product substituting with chlorine for the grafted polymer, a grafted chlorinated polypropylene,

a chlorosulfonated polyethylene,

a solvent and a vulcanizing agent.

Chlorosulfonated polyethylene as synthetic rubber exhibits, after vulcanization, resistance to heat, resistance to chemicals such as acids or alkalis, resistance to abrasion, resistance to weathering and resistance to excellent ozone and is only slightly degraded by ultraviolet rays. Therefore, it was considered that a primary

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for the application of a finishing layer to polyethylene and to rubber could be obtained by conferring on vulcanized chlorosulfonated polyethylene the capacity to receive a finishing layer, the absence of which is the most serious defect of chlorosulfonated polyethylene.

To improve the ability to receive a topcoat, intramolecular polarity is required to as high a degree as possible to keep the ability to receive a topcoat of various paints in a satisfactory state, since rubber has no polarity and therefore, cannot adhere by means of a polarity or a chemical bond.

This means, taking into account the solubility parameter (SP) indicating the density of cohesive energy (wetting between materials), that polar groups are added in the range of the approximate values of SP of polyethylene or rubber as a reference.

Approaching the solubility parameter (SP), that is to say making the degrees of non-polarity or the degrees of polarity equal or neighboring, is only necessary for good adhesion whatever the materials denatured.

The solubility parameters (SP) are as follows:

A first comparative example of the second characteristic of the present invention consists of a primer composition which comprises:

a chlorinated polypropylene grafted approximately 2 to 30 parts,

a chlorosulfonated polyethylene approximately 3 to 40 parts,

a pigment about 0 to 50 parts,

a vulcanizing agent approximately 0 to 10 parts,

a vulcanization accelerator approximately 0 to 5 parts,

an anti-aging agent approximately 0 to 5 parts, and a solvent approximately 40 to 95 parts,

the total being 100 parts.

That is, we examine a primer with chlorosulfonated polyethylene as the main component, in which the grafted chlorinated polypropylene is mixed to improve the ability to form a topcoat. If the amount of the chlorosulfonated polyethylene is 0 parts, the composition is a primer for conventional polyethylene or rubber, and therefore an amount of 3 parts or more is required. If the amount exceeds 30 parts, the ability to form a top coat decreases and if it exceeds 40 parts, the ability to form a top layer decreases considerably.

The amount of the grafted chlorinated polypropylene to be incorporated is in the range of 2 to 30 parts. If the quantity is less than 2 parts, one cannot expect a satisfactory capacity for forming a top coat. If the amount exceeds 30 parts, the heat resistance decreases considerably. Vulcanizing additives are those used for the production of conventional rubber.

A second comparative example of the second characteristic of the present invention consists of a primer composition which comprises:

an EVA grafted approximately 2 to 30 parts,

a chlorosulfonated polyethylene approximately 3 to 40 parts,

a pigment about 0 to 50 parts,

a vulcanizing agent approximately 0 to 10 parts,

a vulcanization accelerator approximately 0 to 5 parts,

an anti-aging agent approximately 0 to 5 parts, and a solvent approximately 40 to 95 parts,

the total being 100 parts.

The incorporation of the grafted EVA aims to confer a good capacity for forming a finishing layer and to improve the adhesiveness to polyethylene. The amount of the chlorosulfonated polyethylene to be incorporated is in the range of 30 to 40 parts. If the quantity is less than 3 parts, we cannot expect polyethylene grafted EVA grafted EEA

chlorosulfonated polyethylene natural rubber (NR)

styrene-butadiene rubber (SBR) chloroprene rubber (CR) acrylonitrile rubber (NBR)

water silicone rubber

7.9 [(cal / ml) 1/2],

8.3-8.5,

8.5-8.7,

8.6-8.9, 7.9-8.4, 8.1-8.7,

8.8-9.2,

8.9-9.4, 23.4, and 7.3.

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dre resistance to heat and if it exceeds 40 parts, the ability to form a top coat is significantly lowered.

The amount of grafted EVA to incorporate is in the range of 2 to 30 parts. If this amount is less than 2 parts, one cannot expect a satisfactory top coat forming capacity, and if it exceeds 30 parts, the heat resistance is considerably lowered.

A third comparative example of the second characteristic of the present invention consists of a composition of primaries which comprises:

a grafted EEA or a substitution product with chlorine of the grafted polymer approximately 2 to 30 parts,

a chlorosulfonated polyethylene approximately 3 to 40 parts,

a pigment about 0 to 50 parts,

a vulcanizing agent approximately 0 to 10 parts,

a vulcanization accelerator approximately 0 to 5 parts,

an anti-aging agent approximately 0 to 5 parts, and a solvent approximately 40 to 95 parts,

the total being 100 parts.

The incorporation of the grafted EEA or of a substitute product with chlorine of the grafted polymer aims to obtain a good capacity for forming a finishing layer as well as to keep the rubber a good capacity immediately.

The amount of the chlorosulfonated polyethylene to be incorporated is in the range of 3 to 40 parts. If the amount is less than 3 parts, no thermal resistance can be expected and if it exceeds 40 parts, the ability to form a top coat is considerably lowered. The amount of grafted EEA to incorporate is in the range of 2 to 30 parts. If this amount is less than 2 parts, one cannot expect a satisfactory ability to form a top coat and if it exceeds 30 parts, the heat resistance is considerably lowered.

The first embodiment of the second characteristic of the present invention consists of a composition of primaries which comprises:

an EVA grafted approximately 1 to 20 parts,

a chlorinated polypropylene grafted approximately 1 to 20 parts,

a chlorosulfonated polyethylene approximately 3 to 40 parts,

a pigment about 0 to 50 parts,

a vulcanizing agent approximately 0 to 10 parts,

a vulcanization accelerator approximately 0 to 5 parts,

an anti-aging agent approximately 0 to 5 parts, and a solvent approximately 40 to 95 parts,

the total being 100 parts.

The combination of grafted EVA and grafted chlorinated polypropylene aims to improve the adhesiveness to polyethylene and to polypropylene and the ability to form a finishing layer.

The amount of the chlorosulfonated polyethylene to be incorporated is in the range of 3 to 40 parts. If this amount is less than 3 parts, one cannot expect heat resistance and if it exceeds 40 parts, one cannot expect a capacity for forming a finishing layer.

The amount of grafted EVA to incorporate is in the range of I to 20 parts. If the quantity is less than 1 part, an improvement in the adhesiveness to the polyethylene cannot be expected. If the amount exceeds 20 parts, the effect of grafted chlorinated polypropylene, or simply grafted polypropylene, is suppressed unless the mixing rate of these is increased, so that it is necessary to increase their mixing rate. Therefore, the appropriate amount of the chlorosulfonated polyethylene to be incorporated will not be retained and the heat resistance is lowered. The mixing rate of the grafted chlorinated polypropylene is in the range of I to 20 parts. If the rate is less than 1 part, no adhesion to polyethylene can be expected. If the level exceeds 20 parts, the effect of the grafted EVA is suppressed, unless its mixing rate is increased, so that it is necessary to increase the mixing rate of the grafted EVA. Therefore, the appropriate amount of the chlorosulfonated polyethylene to be incorporated will not be retained, and the heat resistance is lowered.

The second embodiment in the second characteristic of the present invention consists of a composition of primers which comprises:

a chlorinated polypropylene grafted approximately 1 to 20 parts,

a grafted EEA or a substitution product with chlorine of the grafted polymer approximately 1 to 20 parts,

a chlorosulfonated polyethylene approximately 3 to 40 parts,

a pigment about 0 to 50 parts,

a vulcanizing agent approximately 0 to 10 parts,

a vulcanization accelerator approximately 0 to 5 parts,

an anti-aging agent approximately 0 to 5 parts, and a solvent approximately 40 to 95 parts,

the total being 100 parts.

The combination of grafted EAE or its chlorination product and grafted chlorinated polypropylene aims to

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keep the good capacity immediately to the rubber, to ensure the adhesiveness to the polypropylene and to improve the capacity of formation of a finishing layer.

The amount of the chlorosulfonated polyethylene to be incorporated is in the range of 3 to 40 parts. If the quantity is less than 3 parts, one cannot expect satisfactory heat resistance and if it exceeds 40 parts, one cannot expect a capacity for forming a topcoat.

The amount of grafted EEA to be incorporated is in the range of I to 20 parts. If this amount is less than 1 part, no improvement can be expected in the capacity for forming a topcoat and in the capacity for rubber. If this amount exceeds 20 parts, the effect of the grafted chlorinated polypropylene is suppressed unless the mixing rate thereof is increased, so that it is necessary to increase their mixing rate. Thus, if the proper amount of the chlorosulfonated polyethylene to be incorporated is not assured, the heat resistance is lowered.

The mixing rate of the grafted chlorinated polypropylene is in the range of I to 20 parts. If the rate is less than 1 part, one cannot expect adhesion to polyethylene and an improvement in the ability to form a top coat. If the level exceeds 20 parts, the effect of the grafted EEA is suppressed unless its mixing rate is increased, so that it is necessary to increase the mixing rate of the grafted EEA. Therefore, the appropriate amount of chlorosulfonated polyethylene to be incorporated will not be maintained and the heat resistance is lowered.

A fourth comparative example of the second characteristic of the present invention consists of a composition of primaries which comprises:

an EVA grafted approximately 1 to 20 parts,

a grafted EEA or a substitution product with chlorine of the grafted polymer: approximately 1 to 20 parts,

a chlorosulfonated polyethylene approximately 3 to 40 parts,

a pigment about 0 to 50 parts,

a vulcanizing agent approximately 0 to 10 parts,

a vulcanization accelerator approximately 0 to 5 parts,

an anti-aging agent approximately 0 to 5 parts, and a solvent approximately 40 to 95 parts,

the total being 100 parts.

The combination of grafted EVA and grafted EEA or its chlorination product tends to improve the adhesiveness to polyethylene, to maintain the good “follow-up” capacity with rubber and to ensure the capacity for formation of '' a top coat.

The amount of the chlorosulfonated polyethylene to be incorporated is in the range of 3 to 40 parts. If the amount is less than 3 parts, one cannot expect a satisfactory heat resistance, and if it exceeds 40 parts, one cannot expect a capacity for forming a finishing layer.

The amount of grafted EVA to incorporate is in the range of I to 20 parts. If this amount is less than 1 part, one cannot expect any adhesiveness to the polyethylene. If it exceeds 20 parts, the effect of the grafted chlorinated polypropylene is suppressed, unless their mixing rate is increased, so that it is necessary to increase their mixing rate. Therefore, the proper amount of the chlorosulfonated polyethylene to be incorporated will not be ensured and the heat resistance will be lowered.

The mixing rate of the grafted EEA is in the range of I to 20 parts. If the rate is less than 1 part, one cannot expect an improvement in the forming capacity of a top coat. If the level exceeds 20 parts, the effect of the grafted EVA is suppressed unless its mixing rate is increased, so it is necessary to increase the mixing rate of the grafted EVA. Therefore, the appropriate amount of the chlorosulfonated polyethylene to be incorporated will not be retained, and the heat resistance will be lowered.

The third embodiment of the second characteristic of the present invention consists of a composition of primaries which comprises:

an EVA grafted approximately 1 to 15 parts,

a grafted EVA or a substitution product with chlorine of the grafted polymer approximately 1 to 15 parts,

a chlorinated polypropylene grafted approximately 1 to 15 parts,

a chlorosulfonated polyethylene approximately 4 to 40 parts,

a pigment about 0 to 50 parts,

a vulcanizing agent approximately 0 to 10 parts,

a vulcanization accelerator approximately 0 to 5 parts,

an anti-aging agent approximately 0 to 5 parts, and a solvent approximately 40 to 93 parts,

the total being 100 parts.

The combination of grafted EVA, grafted EEA or its chlorination product and grafted chlorinated polypropylene tends to improve the adhesiveness to polyethylene, to improve the capacity for forming a finishing layer and to improve the capacity rubber follow-up.

The amount of the chlorosulfonated polyethylene to be incorporated is in the range of 4 to 40 parts. If this

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quantity is less than 4 parts, one cannot expect a satisfactory heat resistance, and if it exceeds 40 parts, one cannot expect a capacity for forming a finishing layer.

The amount of grafted EVA to incorporate is in the range of I to 15 parts. If this amount is less than 1 part, an improvement in the adhesiveness to the polyethylene cannot be expected. If it exceeds 15 parts, the effect of the two constituents of the grafted EEA or its chlorinated polymer and of the grafted chlorinated polypropylene is suppressed unless their mixing rate is increased, so that it is necessary to increase the mixing rate of the two constituents. Therefore, the proper amount of chlorosulfonated polyethylene to be incorporated will not be ensured and the heat resistance will be lowered.

The mixing rate of the grafted EEA or the chlorination product of the grafted polymer is in the range of I to 15 parts. If the rate is less than 1 part, one cannot expect an improvement in the ability to form a top coat and the ability to "follow-up" to rubber. If the level exceeds 15 parts, the effect of the two constituents of grafted EVA and grafted chlorinated polypropylene is suppressed unless their mixing rate is increased, so that it is necessary to increase the mixing rate of the two constituents. Therefore, the appropriate amount of the chlorosulfonated polyethylene to be incorporated will not be retained and the heat resistance will be lowered.

The mixing rate of the grafted chlorinated polypropylene is in the range of I to 15 parts. If this rate is less than 1 part, one cannot expect adhesiveness to polypropylene. If the level exceeds 15 parts, the effect of the two constituents of the grafted EVA polymer and of the grafted EEA polymer is suppressed, unless their mixing rate is increased, so that it is necessary to increase the level of mixture of the two constituents. Therefore, the appropriate amount of the chlorosulfonated polyethylene to be incorporated will not be retained and the heat resistance will be lowered.

The primers mentioned above become liquid paints at room temperature by mixing and dispersing the constituents forming the respective primer, and they can therefore be applied by spraying, brushing or roller coating.

When the primer is applied to polyethylene, it is applied so that the dry film has a thickness of about 15 ^ m. When the solvent has evaporated, the film is irradiated with far infrared rays to form a resistant bond to polyethylene. The duration of irradiation with far infrared rays varies depending on the capacity of the heating system or the type of polyethylene. In the case of HDPE, the irradiation is carried out with a 4 KW far infrared heating system for approximately 2.5 to 5 minutes for 0.1 m2 of material to be irradiated, so as to obtain good adhesiveness.

Likewise, in the case of the coating of a rubber, the film may have the same thickness as in the case of polyethylene, and it is strongly bonded to the rubber by the heat treatment by far infrared rays or in an oven with hot air. .

The third characteristic of the present invention consists of a composition of primers in granular or powder form in the solid state at room temperature, in which the solvent has been removed from the constituent primer as for the first primer mentioned above.

In other words, the third characteristic of the present invention consists in that the primary composition contains at least one polymer chosen from grafted EVA, grafted EEA or a product of substitution by chlorine of the grafted polymer, polypropylene. chlorinated grafted.

The grafted EVA preferably has a weight average molecular weight of 1-2 x 105 and a vinyl acetate content of 15-35%.

The grafted chlorinated polypropylene preferably has a weight average molecular weight of 6 to 10 × 10 4 and a chlorine content of 20 to 30%.

The grafted EVA mentioned above preferably has a weight average molecular weight of 5 x 15 x 104 and an ethyl acrylate content of 15% or less. Likewise, the chlorine substitution product of the latter grafted polymer preferably has a chlorine content of 10 to 25%.

A first comparative example of the third characteristic of the present invention consists in that the primary composition comprises an EVA grafted approximately 50 to 100 parts, and a pigment approximately 0 to 50 parts, the total being 100 parts,

the total being 100 parts.

The composition of primers cannot be prepared by a dry process, unless the grafted EVA is not incorporated in an amount of 50 parts or more.

The first embodiment of the third characteristic of the present invention consists in that the composition of primers comprises an EVA grafted approximately 20 to 95 parts,

a chlorinated polypropylene grafted approximately 5 to 60 parts, and a pigment approximately 0 to 50 parts,

the total being 100 parts. If the amount of grafted EVA is less than 20 parts, the grafted chlorinated polypropylene must be incorporated in an amount of at least 30 parts or more, and the dechlorination reaction takes place too vigorously for the preparation to be possible. composition of primers under these conditions by a dry process.

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If the amount of grafted EVA exceeds 95 parts, the appropriate amount of the grafted chlorinated polypropylene to be incorporated cannot be maintained.

If the amount of grafted chlorinated polypropylene is less than 5 parts, an improvement in the ability to form a topcoat and the adhesiveness to polyethylene cannot be expected.

If the amount exceeds 60 parts, the appropriate amount of the grafted EVA to be incorporated into the preparation cannot be ensured, and the dechlorination reaction occurs too vigorously for the primers composition to be prepared under these conditions by a dry process.

The second comparative example of the third characteristic of the present invention consists in that the composition of primers comprises:

an EEA grafted approximately 50 to 100 parts, and a pigment approximately 0 to 50 parts,

the total being 100 parts.

The primer composition cannot be prepared by a dry process, unless the grafted EEA is not incorporated in an amount of 50 parts or more.

The second embodiment of the third characteristic of the present invention consists in that the composition of primers comprises an EEA grafted approximately 20 to 95 parts,

a chlorinated polypropylene grafted approximately 5 to 60 parts, and a pigment approximately 0 to 50 parts,

the total being 100 parts.

If the amount of grafted EVA is less than 20 parts, the grafted chlorinated polypropylene must be incorporated in an amount of at least 30 parts or more, and the dechlorination reaction is carried out too vigorously to be able to prepare the primer composition under these conditions by a dry process.

If the amount of grafted EVA exceeds 95 parts, the proper amount of the grafted chlorinated polypropylene to be incorporated cannot be guaranteed.

If the amount of grafted chlorinated polypropylene is less than 5 parts, an improvement in the ability to form a topcoat and the adhesiveness cannot be expected.

If the amount of the grafted chlorinated polypropylene exceeds 60 parts, the appropriate amount of the grafted EEA to be incorporated into the preparation cannot be guaranteed, and the dechlorination reaction is carried out too vigorously for the composition of the composition to be prepared. primary in such conditions by a dry process.

The third embodiment of the third characteristic of the present invention consists in that the composition of primers comprises:

an EVA grafted approximately 10 to 85 parts,

an EEA grafted around 10 to 85 parts,

a chlorinated polypropylene grafted approximately 5 to 60 parts, and a pigment approximately 0 to 50 parts,

the total being 100 parts.

The mixing rate of the grafted EVA is in the range of 10 to 85 parts. If the amount of grafted EVA is less than 10 parts, one cannot expect the effect of mixing grafted EVA and if it exceeds 85 parts, the mixing rate of grafted EEA and polypropylene grafted chlorine is lowered and one cannot expect the effect of these two constituents.

The amount of grafted EAE to be incorporated is in the range of 10 to 85 parts. If the amount is less than 10 parts, one cannot expect the mixing effect of the grafted EEA. If the amount exceeds 85 parts, the mixing rate of the grafted EVA and the grafted chlorinated polypropylene is lowered and the effect of these two constituents cannot be expected.

The amount of grafted chlorinated polypropylene is in the range of 5 to 60 parts. If the amount of grafted chlorinated polypropylene is less than 5 parts, adhesiveness to polypropylene cannot be expected, and if it exceeds 60 parts, the appropriate amount of grafted EVA or grafted EEA to be incorporated into the preparation cannot be ensured, and the dechlorination reaction is carried out too vigorously so that the composition of primers can be prepared under these conditions by a dry process.

The effective process for mixing and dispersing the components is a hot melt mixture (dry process) with a twin screw extruder.

The spraying can easily be carried out by spraying by freezing a mixed solid product obtained by the use of the twin-screw extruder.

The fourth characteristic of the present invention consists in spraying the formula containing chlorosulfonated polyethylene of the primer of the second characteristic of the invention mentioned above, from which the solvent has been removed.

In other words, the fourth characteristic of the present invention consists in the composition of powder type primers which comprises at least one polymer chosen from a grafted EVA, a grafted EEA or a chlorination product of the grafted polymer,

a grafted chlorinated polypropylene,

a chlorosulfonated polyethylene and a vulcanizing agent.

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A first comparative example of the fourth characteristic of the present invention consists of the composition of powder type primers, which comprises:

a chlorinated polypropylene grafted approximately 5 to 90 parts,

a chlorosulfonated polyethylene approximately 10 to 95 parts,

a pigment about 0 to 50 parts,

a vulcanizing agent approximately 0 to 10 parts,

a vulcanization accelerator about 0 to 5 parts, and an anti-aging agent about 0 to 5 parts, the total being 100 parts.

The amount of the chlorosulfonated polyethylene to be incorporated is in the range of 10 to 95 parts. If this amount is less than 10 parts, satisfactory heat resistance cannot be expected, and if it exceeds 95 parts, the ability to form a topcoat is completely lost.

The amount of grafted chlorinated polypropylene to be incorporated is in the range of 5 to 90 parts. If the amount is less than 5 parts, one cannot expect a satisfactory top coat forming capacity. If the amount exceeds 90 parts, the heat resistance is lost.

A second comparative example of the fourth characteristic of the present invention consists of the composition of powder type primers which comprises:

an EVA grafted approximately 5 to 90 parts,

a chlorosulfonated polyethylene approximately 10 to 95 parts,

a pigment about 0 to 50 parts,

a vulcanizing agent approximately 0 to 10 parts,

a vulcanization accelerator approximately 0 to 5 parts, and an anti-aging agent approximately 0 to 5 parts,

the total being 100 parts.

The amount of chlorosulfonated polyethylene to be incorporated is in the range of 10 to 95 parts. If this amount is less than 10 parts, satisfactory heat resistance cannot be expected, and if it exceeds 95 parts, the finishing coat ability is completely lost.

The amount of EVA grafted is in the range of 5 to 90 parts. If this amount is less than 5 parts, one cannot expect a satisfactory top coat forming capacity. If it exceeds 90 parts the heat resistance is lost.

A third comparative example of the fourth characteristic of the present invention consists of the composition of powder type primers which comprises:

a grafted EEA or a chlorination product of the grafted polymer approximately 5 to 90 parts,

a chlorosulfonated polyethylene approximately 10 to 95 parts,

a pigment about 0 to 50 parts,

a vulcanizing agent approximately 0 to 10 parts,

a vulcanization accelerator approximately 0 to 5 parts, and an anti-aging agent approximately 0 to 5 parts,

the total being 100 parts.

The amount of the chlorosulfonated polyethylene to be incorporated is in the range of 10 to 95 parts. If the amount is less than 10 parts, satisfactory heat resistance cannot be expected and if it exceeds 95 parts, the ability to form a topcoat is completely lost.

The amount of the grafted EEA or the chlorine product of the graft polymer to be incorporated is in the range of 5 to 95 parts. If the quantity is less than 5 parts, one cannot expect a satisfactory finishing coat capacity. If the amount exceeds 90 parts, the heat resistance is lost.

The first embodiment of the fourth characteristic of the present invention consists of the composition of powder type primers which comprises:

a chlorinated polypropylene grafted approximately 2.5 to 45 parts,

an EVA grafted approximately 2.5 to 45 parts,

a chlorosulfonated polyethylene approximately 10 to 95 parts,

a pigment about 0 to 50 parts,

a vulcanizing agent approximately 0 to 10 parts,

a vulcanization accelerator approximately 0 to 5 parts, and an anti-aging agent approximately 0 to 5 parts,

the total being 100 parts.

The amount of the chlorosulfonated polyethylene to be incorporated is in the range of 10 to 95 parts. If this amount is less than 10 parts, satisfactory heat resistance cannot be expected, and if it exceeds 95 parts, the ability to form a topcoat is completely lost.

The amount of the grafted chlorinated polypropylene to be incorporated is in the range of 2.5 to 45 parts. If this amount is less than 2.5 parts, the adhesiveness to polypropylene is in no way improved. If the amount exceeds 45 parts, the effect of the grafted EVA is suppressed unless the amount of EVA

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grafted to incorporate is not increased. Therefore, the amount must be increased, so that the amount of the chlorosulfonated polyethylene to be incorporated cannot be maintained within the proper range, and the heat resistance is lowered.

The amount of grafted EVA to incorporate is in the range of 2.5 to 45 parts. If the amount is less than 2.5 parts, an improvement in the adhesiveness to the polyethylene cannot be expected. If the amount exceeds 45 parts, the effect of the grafted chlorinated polypropylene is suppressed, unless the amount of this to be incorporated is increased. Therefore, the amount should be increased so that the amount of the chlorosulfonated polyethylene to be incorporated cannot be maintained within an appropriate range, and the heat resistance is lowered.

The second embodiment of the fourth characteristic of the present invention consists of the composition of powder type primers which comprises:

a chlorinated polypropylene grafted approximately 2.5 to 45 parts,

a grafted EEA or a substitution product with chlorine of the grafted polymer approximately 2.5 to 45 parts,

a chlorosulfonated polyethylene approximately 10 to 95 parts,

a pigment about 0 to 50 parts,

a vulcanizing agent approximately 0 to 10 parts,

a vulcanization accelerator approximately 0 to 5 parts, and an anti-aging agent approximately 0 to 5 parts,

the total being 100 parts.

The amount of the chlorosulfonated polyethylene to be incorporated is in the range of 10 to 95 parts. If the amount is less than 10 parts, satisfactory heat resistance cannot be expected, and if it exceeds 95 parts, the ability to form a topcoat is completely lost.

The amount of the grafted chlorinated polypropylene to be incorporated is in the range of 2.5 to 45 parts. If the amount is less than 2.5 parts, the adhesiveness to polypropylene is not improved at all. If the amount exceeds 45 parts, the effect of the grafted EVA is suppressed, unless the amount of grafted EEA to be incorporated is increased. Therefore, the amount must be increased, so that the amount of the chlorosulfonated polyethylene to be incorporated cannot be maintained within an appropriate range, and the heat resistance is lowered.

The amount of grafted EEA to incorporate is in the range of 2.5 to 45 parts. If the amount is less than 2.5 parts, an improvement in the adhesiveness to the polyethylene cannot be expected. If the quantity exceeds 45 parts, the effect of the grafted polypropylene is suppressed, unless the quantity of these to be incorporated is increased. Therefore, the amount must be increased, so that the amount of the chlorosulfonated polyethylene to be incorporated cannot be maintained within an appropriate range and the heat resistance is lowered.

A fourth comparative example of the fourth characteristic of the present invention consists of the composition of powder type primers which comprises:

an EVA grafted approximately 2.5 to 45 parts,

a grafted EEA or a chlorine substitution product of the grafted polymer approximately 2.5 to 45 parts, a chlorosulfonated polyethylene approximately 10 to 95 parts,

a grafted EEA or a substitution product with chlorine of the grafted polymer approximately 2.5 to 45 parts,

a chlorosulfonated polyethylene approximately 10 to 95 parts,

a pigment about 0 to 50 parts,

a vulcanizing agent approximately 0 to 10 parts,

a vulcanization accelerator approximately 0 to 5 parts, and an anti-aging agent approximately 0 to 5 parts,

the total being 100 parts.

The amount of the chlorosulfonated polyethylene to be incorporated is in the range of 10 to 95 parts. If the amount is less than 10 parts, sufficient heat resistance cannot be expected and if it exceeds 95 parts, the ability to form a topcoat is completely lost.

The amount of grafted EVA to incorporate is in the range of 2.5 to 45 parts. If the amount is less than 2.5 parts, the adhesiveness to the polyethylene is not improved at all. If the amount exceeds 45 parts, the effect of the grafted EEA or the chlorine substitution product of the grafted polymer is suppressed unless the amount of grafted EVA to be incorporated is increased. Therefore, the amount must be increased, so that the amount of the chlorosulfonated polyethylene to be incorporated cannot be maintained within an appropriate range and the heat resistance is lowered.

The amount of grafted EEA to incorporate is in the range of 2.5 to 45 parts. If this amount is less than 2.5 parts, one cannot expect a satisfactory ability to form a top coat. If it exceeds 45 parts, the effect of the grafted EVA is suppressed unless the quantity to be incorporated is increased. Therefore, the amount must be increased, so that the amount of the chlorosulfonated polyethylene to be incorporated cannot be maintained within an appropriate range and the heat resistance is lowered.

The third embodiment of the fourth characteristic of the present invention consists of the composition of powder type primers which comprises:

an EVA grafted approximately 2.5 to 30 parts,

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CH 686 018G A3

a grafted EEA or a substitution product with chlorine of the grafted polymer approximately 2.5 to 30 parts,

a chlorinated polypropylene grafted approximately 2.5 to 30 parts,

a chlorosulfonated polyethylene approximately 10 to 92.5 parts a pigment approximately 0 to 50 parts,

a vulcanizing agent approximately 0 to 10 parts,

a vulcanization accelerator about 0 to 5 parts, and an anti-aging agent about 0 to 5 parts the total being 100 parts.

The amount of the chlorosulfonated polyethylene to be incorporated is in the range of 12 to 92.5 parts. If this amount is less than 10 parts, satisfactory heat resistance cannot be expected and if it exceeds 92.5 parts, the ability to form a topcoat is completely lost.

The amount of grafted EVA to incorporate is in the range of 2.5 to 30 parts. If this amount is less than 2.5 parts, the adhesiveness to the polyethylene is not improved at all. If this amount exceeds 30 parts, the effect of the two constituents of the grafted EEA or of the chlorination product of the grafted polymer and of the grafted chlorinated polypropylene is suppressed, unless the amount of the two constituents to be incorporated is not increased. Therefore, the amount must be increased, so that the amount of the chlorosulfonated polyethylene to be incorporated cannot be kept within an appropriate range and the heat resistance is lowered.

The amount of EEA or chlorine product of the graft polymer to be incorporated is in the range of 2.5 to 30 parts. If the amount is less than 2.5 parts, one cannot expect an improvement in the ability to form a topcoat and the ability to "follow-up" to the rubber. If the amount exceeds 30 parts, the effect of the two constituents of the grafted EVA and the grafted chlorinated polypropylene is suppressed unless the amount of the two incorporated constituents is not increased. Therefore, the amount must be increased, so that the amount of the chlorosulfonated polyethylene to be incorporated cannot be maintained within an appropriate range and the heat resistance is lowered.

The amount of the grafted chlorinated polypropylene to be incorporated is in the range of 2.5 to 30 parts. If the amount is less than 2.5 parts, an improvement in the adhesiveness to polypropylene cannot be expected. If the amount exceeds 30 parts, the effect of the two constituents of the grafted EVA and of the grafted EEA or of the chlorination product of the grafted polymer is suppressed unless the amount of these to be incorporated is increased. Therefore, the amount must be increased, so that the amount of the chlorosulfonated polyethylene to be incorporated cannot be maintained within an appropriate range and the heat resistance is lowered.

When the composition of primers is prepared by a process comprising a heating stage, vulcanization of the chlorosulfonated polyethylene takes place. Therefore, spraying by the dry method (using a twin screw extruder or the like) is impossible, so that the composition of powder-type primers was prepared by a wet method.

The wet process is a spray drying process, and the powder type primer passing through an 80 mesh aperture sieve (particular size in the range of 44-177 µm) has typically been prepared from the type primer solvent of the first comparative example of the second characteristic of the present invention with a spray dryer.

For example, the powder type primer of the first comparative example of the fourth characteristic of the present invention has the following particle mesh dimensions

The powder type primer is applied to polyethylene, rubber, etc. by a fluidized immersion process. It is not necessary to melt and spread the primer during its application by fluidized immersion, since it is subjected to a heat treatment by irradiation with rays in the far infrared after the application stage, and by therefore, the material to be applied should only undergo preliminary heating to around 100 ° C.

The primer applied by the fluidized immersion process forms a particulate layer on the surface of the material to be coated such as polyethylene (for example HDPE), rubber etc., which layer is melted and spread by irradiation with rays in the far infrared and forms a bond

Mesh opening (um)

determination (%)

80 (177) 100 (149) 145 (105) 200 (74) 250 (63) 350 (44)

2.2 7.5 16.1

18.1

24.2 36.9

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CH 686 018G A3

resistant with the material to be coated. The treatment time of the primer with rays in the far infrared varies according to the primer, the film thickness and the materials to be applied. When the primer of the third characteristic of the present invention and a polyethylene (HDPE) are used as the material to be coated and the film has a thickness of 50 μm, the heat treatment is 3 minutes with a heating system of 4 kW for 0.1 m2 of the material to be coated. Under the same conditions of primer, film thickness and heating system, except that the material to be coated is a rubber, the heat treatment time is approximately 40 seconds.

When using the powder type primer of the fourth characteristic of the present invention, the heat treatment is carried out for 5 minutes with the same heating system above regardless of the thickness of the film or the materials to be coated (because the heat treatment time is extended by vulcanization). The primer thus heat treated binds strongly to the material to be coated and has a good ability to form a finishing layer.

The fifth feature of the present invention is an efficient heating process. In other words, although heating is not necessary for certain materials to be coated, better adhesiveness to non-polar materials is generally obtained by heating (or in some cases by heating under pressure).

An intimate mixture of the material to be coated (polyethylene, polypropylene or rubber) and a primer (grafted EVA, EEA etc.) is improved at the interface of these molecules by heating, and better adhesiveness can be obtained.

As the main constituent of the present invention is a denatured polyolefin primer, the absorption wavelength of infrared rays for its heating is in the range of 5 to 50 µm, and the primer should only have the function of forming a chemical bond only on the surface of the material to be coated such as polyethylene or rubber. Therefore, the heating system used in the present invention is a far infrared heating system and the wavelength of the radiated infrared rays is in the range of 3 to 50 µm. It can be said in this connection that the wavelengths of infrared rays irradiated by other heating systems are in the range of 0.7 to about 2 µm for a nichrome film, from 0.7 to about 3 µm for an infrared lamp and from 0.7 to about 7 (im for a heating system consisting of an element in a quartz sheath.

In accordance with the present invention, the far infrared heating system efficiently produces far infrared rays in a wide range of 3 to 50 and the bonding reaction on the surface layer ends in a short time, so that the 'A product bound to polyethylene or rubber is obtained with little decomposition by heating.

As described above, the material of the present invention has an SP value close to that of polyethylene, polypropylene and synthetic rubbers, so that it easily mixes and wets with others. Likewise, a grafted polymer of an unsaturated dicarboxylic acid and of EVA or EEA has an SP value close to that of polyethylene and rubber and it has a very good ability to form a finish coating by intra-molecular polarization by a vinyl acetate group, an ethyl acrylate group, in particular a carbonyl group in the case of maleinization.

Furthermore, the grafted EVA and EEA (in particular EEA) have good flexibility. Chlorosulfonated polyethylene is a synthetic rubber belonging to the class of chloroprene rubbers.

A Cl group bound to the polymer inhibits the crystallization caused by the orderly arrangement of the polymer and gives the polymer flexibility.

Likewise, the SO2CI group becomes a crosslinking point which gives the polymer excellent properties such as resistance to heat, resistance to solvents (for example resistance to petrol), resistance to chemicals, etc.

Therefore, polyethylene, polypropylene or rubber can be bonded by coating or thermo-contact to coat or print paint or ink. For example, if a polyethylene pipe used outdoors, such as a petroleum pipe, is treated with the present invention to coat it with a fluorinated resin paint, the appearance of the pipe is improved by coloring and the durability of the pipe is greatly improved by the ultraviolet screen effect, paint. If the primer of the present invention is applied to the internal surface of a mold during injection molding of a polyethylene article, an injection molded polyethylene article can be obtained which can, if desired, be coated or printed after separation from the mold and which has excellent weather resistance. Likewise, a solid primer composition prepared by solventless thermal fusion kneading can be molded together with polyethylene by a two-layer extrusion process to form a pipe, plate or other articles which can be coated. or printed. In addition, the present invention has excellent follow-up ability for rubber. Therefore, the present invention has the effect of not only preventing oxidative degradation of synthetic rubber by oxygen or ozone, preventing contamination by dust etc., preventing odor of synthetic rubbers and improve abrasion, but it can also give polyethylene, polypropylene and rubber a colored appearance without degradation of the latter in comparison with the black coloration of polyethylene and rubber, a conventional measure to prevent degradation by weathering . Similarly, the presen16

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The invention considerably improves the heat resistance, the petrol resistance and the chemical resistance of the primer itself.

As a result, the composition of primers of the present invention and the polyethylene which is subjected to a treatment by far infrared rays as a means of heating after coating with the primer can very easily retain their shape. Likewise, for synthetic rubbers, products coated with primer can be obtained without degradation of the properties and the heat treatment can be carried out easily and effectively in a very short time. Therefore, it is clear that the present invention allows the application or demand for polyethylene, polypropylene and rubber articles to be greatly expanded.

Example

Table 1 gives the properties of the primers according to the present invention.

Table 2 gives for comparison the properties of the comparative primers incorporating either a grafted polymer of an unsaturated dicarboxylic acid and an ethylene-vinyl acetate copolymer and / or a grafted polymer of an unsaturated dicarboxylic acid and a ethylene ethyl acrylate copolymer or a chlorination product of the grafted polymer, ie a chlorinated polypropylene in which a grafted polymer of a dicarboxylic acid is subjected to a substitution of chlorine.

Table 3 gives by way of comparison the properties of the additional comparative primers incorporating a grafted polymer of an unsaturated carboxylic acid and of an ethylene-vinyl acetate copolymer and / or a grafted polymer of an unsaturated dicarboxylic acid and of a ethylene-ethyl acrylate copolymer or a chlorination product of the graft polymer, and a chlorinated polypropylene in which the polypropylene is simply subjected to chlorine substitution.

The present invention is not limited to the embodiments which have just been described, it is on the contrary subject to modifications and variants which will appear to those skilled in the art.

17

CJ>

in

Ol en en o

Ul

O

03

in ro in ro o

Table 1 Example

First characteristic

Second characteristic

Claim No.

6

7

8

15

16

17

Incorporated constituent

Maleinized EVA * 1

7

-

5

2

-

2

Maleinized EEA * 2

-

7

5

-

2

2

Chlorinated polypropylene * 3

7

7

5

3

3

3

Chlorosulfonated polyethylene * 4

-

-

-

15

15

15

Titanium oxide (rutile type)

5

5

5

25.5

25.5

25.5

Vulcanizing agent * 5

-

-

-

5

5

5

Vulcanization accelerator * ^

-

-

-

0.5

0.5

0.5

Organic titanium compound * 7

-

-

-

-

-

-

Anti-aging agent * 8

-

-

0.5

0.5

0.5

Toluene

80

81

80

49

49

49

Total quantity

100

100

100

100

100

100

Properties of the primary composition film * 9

Breaking strength (kg / cm2)

65

40

55

90

65

70

Elongation (%)

240

150

205

210

300

250

in o

Ui o

co o

ro

Ü1

Table 1 Example (continued)

First characteristic

Second characteristic

Claim No.

6

7

8

15

16

17

Adhesion of the primary to the matrix * 10

LDPE

100/100

80/100

100/100

90/100

75/100

85/100

HDPE

100/100

80/100

100/100

90/100

75/100

85/100

PP

100/100

100/100

100/100

95/100

90/100

90/100

NR

100/100

90/100

100/100

100/100

100/100

100/100

SBR

100/100

90/100

100/100

100/100

100/100

100/100

NBR

100/100

100/100

100/100

100/100

100/100

100/100

CR

100/100

100/100

100/100

100/100

100/100

100/100

EPT

100/100

90/100

100/100

100/100

100/100

100/100

Adhesion of the top coat * 11

Urethane paint

100/100

100/100

100/100

100/100

100/100

100/100

Fluorine type paint

100/100

100/100

100/100

100/100

100/100

100/100

Water resistance * 12

HDPE

0

O

o o

o o

SBR

o o

o o

o o

Table 1 Example (continued)

First characteristic

Second characteristic

Claim No.

6

7

8

15

16

17

Heat resistance * 13

a a

-

O

O

o

Weather resistance * 14

HDPE

O

O

o

O

o o

SBR

O

o o

O

o o

in

Ol

O) o

Ol o

• e. Ol

-tv o

u

Ol co o

l \ J Ol

IO

o

Table 1 Example (continued)

ro o

Claim No.

Third characteristic 23 24 25

Incorporated component Maleinized EVA * 1 Maleinized EEA * 2 Chlorinated polypropylene * 3 Chlorosulfonated polyethylene * 4 Titanium oxide (rutile type)

Vulcanizing agent * 5 Vulcanizing accelerator * 6 Organic titanium compound * 7 Anti-aging agent * 8 Toluene Total quantity

Properties of the primer composition film * 9 Breaking strength (kg / cm2)

Elongation (%)

40

20

40

100

85,250

40 20

40

100

55 190

20 20 20

40

Fourth characteristic 32 33 34

100

70 210

6

30 48 10 1

100

90 210

4 6

30 48 10 1

100

65,300

4 4 6

30 44 10 1

100

70,250

O X

O) 00

o>

00

O>

co

45 50 55 60

35 40

o

IO tn ro o m o

Ul

Table 1 Example (continued)

Third characteristic

Fourth characteristic

Claim No.

23

24

25

47

48

50

Adhesion of the primary to the matrix * 10

LDPE

100/100

80/100

100/100

90/100

75/100

85/100

HDPE

100/100

80/100

100/100

90/100

75/100

85/100

PP

100/100

100/100

100/100

95/100

90/100

90/100

NR

100/100

90/100

100/100

100/100

100/100

100/100

SBR

100/100

90/100

100/100

100/100

100/100

100/100

NBR

100/100

100/100

100/100

100/100

100/100

100/100

CR

100/100

100/100

100/100

100/100

100/100

100/100

EPT

100/100

90/100

100/100

100/100

100/100

100/100

Adhesion of the top coat * 11

Urethane paint

100/100

100/100

100/100

100/100

100/100

100/100

Fluorine type paint

100/100

100/100

100/100

100/100

100/100

100/100

Water resistance * 12

HDPE

G

O

o o

o o

SBR

o o

o o

o o

Table 1 Example (continued)

Third characteristic

Fourth characteristic

Claim No.

23

24

25

47

48

50

Heat resistance * 13

a a

-

O

O

O

Weather resistance * 14

HDPE

O

O

o

O

o o

SBR

O

O

o o

o o

■ U Ul w

Ol co o

ro o

Table 2 Comparative example

Test No.

Incorporated component Maleinized EVA * 1 Maleinized EEA * 2 Chlorinated polypropylene * 3 Chlorosulfonated polyethylene * 4 Titanium oxide (rutile type)

Vulcanizing agent * 5 Vulcanizing accelerator * 6 Organic titanium compound * 7 Anti-aging agent * 8 Toluene Total quantity

Properties of the primer composition film * 9 Breaking strength (kg / cm2)

Elongation (%)

80 100

45 80

15

25.5

5

0.5

0.5 49 100

75 120

60

40

100

45 80

10

30 48 10 1

100

75 120

88,100

35,200

15

25.5

5

0.5

0.5

49,100

50,355

60

40

100

35,200

10

30 48 10 1

100

50,355

50 55 60 65

40 45

OS Oi w o ro

U1

M

O

ai i.

O

Ol

Table 2 Comparative example (continued)

Test No.

1

2

3

4

5

6

7

8

Adhesion of the primary to the matrix * 10

PEdb

100/100

100/100

100/100

100/100

80/100

75/100

80/100

75/100

HDPE

100/100

100/100

100/100

100/100

80/100

75/100

80/100

75/100

PP

70/100

90/100

70/100

90/100

80/100

80/100

80/100

80/100

NR

100/100

100/100

100/100

100/100

95/100

100/100

95/100

100/100

SBR

100/100

100/100

100/100

100/100

95/100

100/100

95/100

100/100

NBR

100/100

100/100

100/100

100/100

100/100

100/100

100/100

100/100

EPT

100/100

100/100

100/100

100/100

95/100

100/100

95/100

100/100

Adhesion of the top coat * 11

Urethane paint

95/100

95/100

95/100

95/100

95/100

95/100

95/100

95/100

Fluorine type paint

100/100

100/100

100/100

100/100

100/100

100/100

100/100

100/100

Water resistance * 12

PEhd o

o

O

O

O

O

O

O

SBR

o o

o o

O

O

O

o

Table 2 Comparative example (continued)

Test No.

1

2

3

4

5

6

7

8

Heat resistance * 13

-

O

-

O

-

O

-

O

Weather resistance * 14

PEhd o

o

O

O

O

o

O

o

SBR

o o

o

O

O

o o

o

Ol o

co en ro en

Table 2 Comparative example (continued)

Test No.

Incorporated component Maleinized EVA * 1 Maleinized EEA * 2 Chlorinated polypropylene * 3 Chlorosulfonated polyethylene * 4 Titanium oxide (rutile type)

Vulcanizing agent * 5 Vulcanizing accelerator * 6 Organic titanium compound * 7 Anti-aging agent * 8 Toluene Total quantity

Properties of the primer composition film * 9 Breaking strength (kg / cm2)

Elongation (%)

10

11

12

5 15 25.5 5

0.5

3 2

15

25.5

5

0.5

10 30 48 10 1

6 4

30 48 10 1

0.5 49 100

0.5 49 100

100

100

110,280

60 220

110,280

60 220

ro

U1

45 50 55 60

AT

o co

Ol co o

20 25

U1

o

Table 2 Comparative example (continued)

Test No.

9

10

11

12

Adhesion of the primary to the matrix * 10

PEdb

75/100

90/100

75/100

90/100

HDPE

75/100

90/100

75/100

90/100

PP

100/100

85/100

100/100

85/100

NR

100/100

100/100

100/100

100/100

SBR

100/100

100/100

100/100

100/100

NBR

100/100

100/100

100/100

100/100

CR

100/100

100/100

100/100

100/100

EPT

100/100

100/100

100/100

100/100

Adhesion of the top coat * 11

Urethane paint

100/100

95/100

100/100

95/100

Fluorine type paint

100/100

100/100

100/100

100/100

Water resistance * 12

HDPE

o

O

o

O

SBR

o o

o o

Table 2 Comparative example (continued)

Test No.

9

10

11

12

Heat resistance * 13

o o

o

O

Weather resistance * 14

HDPE

o o

o o

SBR

o o

o o

O X

o> œ o>

8

O>

w

<J)

o en en en o

in

■ t »

o

05 in

05

o i \) in ro o

Table 3 Additional comparative example

Test No. (compare with Table 1, claim No.) 13 (6) 14 (7) 15 (8) 16 (15) 17 (16) 18 (17)

Incorporated constituent

Maleinized EVA * 1

7

-

5

2

-

2

EEA meléinsié * 2

-

7

5

-

2

2

Chlorinated polypropylene * 3

-

-

-

-

-

-

Simply chlorinated polypropylene * 15

7

7

5

3

3

3

Chlorosulfonated polyethylene * 4

-

-

-

15

15

15

Rutile titanium oxide)

5

5

5

25.5

25.5

25.5

Vulcanizing agent * 5

-

-

-

5

5

5

Vulcanization accelerator * 6

-

-

-

0.5

0.5

0.5

Organic titanium compound * 7

-

-

-

-

-

-

Anti-aging agent * 8

-

-

-

0.5

0.5

0.5

Toluene

81

81

80

49

49

47

Total quantity

100

100

100

100

100

100

Properties of the primary composition film * 9

Breaking strength (kg / cm2)

84

56

75

95

69

84

Elongation (%)

300

195

260

220

285

265

■ t ”.

tn

■ t>.

o co o

Table 3 Additional comparative example (continued)

ro

• Vl

Test No. (compare with Table 1, claim No.)

13 (6)

14 (7)

15 (8)

16 (15)

17 (16)

18 (17)

Adhesion of the primary to the matrix * 10

LDPE

100/100

100/100

100/100

90/100

75/100

85/100

HDPE

100/100

100/100

100/100

90/100

75/100

85/100

PP

100/100

100/100

100/100

95/100

90/100

90/100

NR

100/100

100/100

100/100

100/100

100/100

100/100

SBR

100/100

100/100

100/100

100/100

100/100

100/100

NBR

100/100

100/100

100/100

100/100

100/100

100/100

CR

100/100

100/100

100/100

100/100

100/100

100/100

EPT

100/100

100/100

100/100

100/100

100/100

100/100

Adhesion of the top coat * 11

Urethane paint

95/100

90/100

95/100

95/100

100/100

95/100

Fluorine type paint

100/100

100/100

100/100

100/100

100/100

100/100

Water resistance * 12

HDPE

G

G

G

G

o

G

SBR

G

G

G

G

G

G

O

o>

00 O)

00

O>

w

Table 3 Additional comparative example (continued)

Test No. (compare with Table 1, claim No.) 13 (6) 14 (7) 15 (8) 16 (15) 17 (16) 18 (17)

Heat resistance * 13 a a - o o o Weather resistance * 14

PEhd O O O O O O

SBR O O O O O O

O) Ol

O)

o m

U1

Ol o

Ol

AT

o

00

01

w o

ro

Ol ro o

Table 3 Additional comparative example (continued)

Test No. (compare with Table 1, claim No.)

19 (23)

20 (24)

21 (25)

22 (32)

23 (33)

24 (34)

ro oo

Incorporated component maleinized EVA * '

Maleinized EEA * 2 Chlorinated polypropylene * 3 Simply chlorinated polypropylene * 15 Chlorosulfonated polyethylene * 4 Titanium oxide (rutile type)

Vulcanizing agent * 5 Vulcanizing accelerator * 6 Organic titanium compound * 7 Anti-aging agent * 8 Toluene Total quantity

Properties of the primer composition film * 9 Breaking strength (kg / cm2)

Elongation (%)

40

20 40

100

102,220

40 20 40

100

70 160

20 20

20

40

100

95 203

6

30 48 10 1

100

95 210

6

30 48 10 1

1

100

69,285

4 4

6

30 44 10 1

100

84,265

O

O) œ

O)

00

O>

co

Ol o

-U Ol o

Ol ru en ro o

Table 3 Additional comparative example (continued)

ro co

Test No. (compare with Table 1, claim No.)

19 (23)

20 (24)

21 (25)

22 (32)

23 (33)

24 (34)

Adhesion of the primary to the matrix * 10

LDPE

100/100

100/100

100/100

90/100

75/100

85/100

Phd

100/100

100/100

100/100

90/100

75/100

85/100

PP

100/100

100/100

100/100

95/100

90/100

90/100

NR

100/100

100/100

100/100

100/100

100/100

100/100

SBR

100/100

100/100

100/100

100/100

100/100

100/100

NBR

100/100

100/100

100/100

100/100

100/100

100/100

CR

100/100

100/100

100/100

100/100

100/100

100/100

EPT

100/100

100/100

100/100

100/100

100/100

100/100

Adhesion of the top coat * 11

Urethane paint

95/100

90/100

95/100

95/100

95/100

95/100

Fluorine type paint

100/100

100/100

100/100

100/100

100/100

100/100

Water resistance * 12

HDPE

O

o

G

G

G

G

SBR

o

G

G

G

G

G

Table 3 Additional comparative example (continued)

Test No. (compare with Table 1, claim No.)

19 (23)

20 (24)

21 (25)

22 (32)

23 (33)

24 (34)

Heat resistance * 13

a a

-

O

O

O

Weather resistance * 14

HDPE

O

G

G

G

G

G

SBR

O

O

O

O

O

O

O X

o>

00

o>

00

O>

GJ

In ol

A O

GJ Ol

OJ O

IO Ol ro o

Note:

M Polymer grafted with an ethylene-vinyl acetate and maleic anhydride copolymer having a weight average molecular weight of approximately 1.7 x 105 and a vinyl acetate content of 25%.

* 2 Chlorinated graft polymer of an ethylene-ethyl acrylate and maleic anhydride copolymer having a weight average molecular weight of approximately 105, an ethyl acrylate content of approximately 10% and a chlorine content d 'around 20%.

* 3 Chlorinated grafted polymer of polypropylene and maleic anhydride having a weight average molecular weight of approximately 8 x 104 and a chlorine content of approximately 25%.

* 4 Chlorosulfonated polyethylene having a weight average molecular weight of approximately 2 × 105, a chlorine content of approximately 30% and a sulfur content of approximately. 1.5%, and represented by the general structural formula [(C2H4-xClx) nCH2CHS02CI] m 0.3.

* 5 Tribasic lead maleate.

* 6 Tetraethylthiuram disulfide * 7 Di-iso-propoxy-bis (acetylacetonato) titanium * 8 4,4'-thio-bis (6-tert-butyl-3-methylphenol).

* 9 In accordance with the tensile test of “vulcanized rubber, physical tests” (1) of JIS-K-6301, using the dumbbell test tube n ° 1.

* 10 According to the test with the grid “general methods of test of paints” 6.15 of JIS-K-5400; each of the primer compositions having a film thickness of 15 (im (except 50 μm for the powder type). LDPE: low density polyethylene; HDPE: high density polyethylene; PP: polypropylene; NR: natural rubber, SBR: styrene rubber butadiene; NBR: acrylonitrile rubber, CR: chloroprene rubber; EPT: ethylene-propylene rubber. * 11 The adhesion of paints of urethane type and of fluorine type to the respective primary compositions of the examples are measured in accordance with the test in "General paint test methods" grid 6.15 of JlS-K-5400, the urethane type paint used is "UNIMARIN" (registered trademark) and the fluoride type paint used is "FLOWREX" (trademark deposited), the film thickness being 50 µm, respectively.

* 12 In accordance with the test of resistance to water of “general methods of test of paints” 7.2 of JIS-K-5400; when the substrate (to be coated) is HDPE, the material of the outer layer is "FLOWREX" (registered trademark), and when the substrate is of SBR, the material of the outer layer is "UNIMARIN" (registered trademark ).

The respective primer compositions of the examples have a film thickness of 15 µm (except 50 µm for the powder type) and the respective outer layer materials have a film thickness of 50 µm.

Rating of the evaluation: O: No problem for 12 months; O: No problem for 6 months; A: No problem for 1 month; X: Blistering after a month or more.

* 13 In accordance with the method of measurement of the temperature of softening of the “method of test of the adhesives for the car” 13 of JIS-K 6829, the test tubes are the samples subjected to the shear test, each one is coated with SBR with a composition of primers of the example subjected to a heat treatment and laminated with an adhesive of the cyanacrylate type.

Rating of the evaluation: o: 71 ° C or more; o: 51-71 ° C; a: 40-50 ° C; X: 39 ° C or less.

* 14 Accelerated measurement of weather resistance by means of a weather resistance measuring machine of the sunlight type; when the substrate (to be coated) is HDPE, the material of the outer layer is "FLOWREX" (registered trademark) and when the substrate is SBR, the material of the outer layer is "UNIMARIN" (registered trademark) . The respective primer compositions of the examples have a film thickness of 15 µm (except 50 µm for the powder type), and the materials of the respective outer layers have a film thickness of 50 µm.

Rating of the evaluation: O: No problem for 4000 hours; O: No problem for 1000 hours; A: No problem for 600 hours; X: cracking, cracking, marked decrease in gloss or change in color.

(When the substrate is SBR, a color difference (DE) in the range of 0.5-1.0 caused by a rubber migrating substance is considered not to be a problem).

* 15 Chlorinated polypropylene in which the polypropylene is simply subjected to a substitution of chlorine without being grafted by polymerization with maleic anhydride, having a weight average molecular weight of approximately 25 x 104 and a chlorine content of approximately 29, 5%.

5

10

15

20

25

30

35

40

45

50

55

60

65

CH 686 018G A3

Claims (1)

Claims 1. Composition of primers for the pretreatment of coatings comprising (A) at least one polymer chosen from a grafted polymer of an unsaturated dicarboxylic acid and of an ethylene-vinyl acetate copolymer (a), a grafted polymer of an acid unsaturated dicarboxylic acid and an ethylene-ethyl acrylate copolymer (b) or a chlorinated product of the grafted polymer (c), (B) a chlorinated polypropylene in which a grafted polymer of an unsaturated dicarboxylic acid and polypropylene is subjected to a substitution of chlorine and (C) a solvent. 2. The composition of primers according to claim 1, in which this grafted polymer of an unsaturated dicarboxylic acid and of an ethylene-acetate copolymer of this vinyl (a) has a weight average molecular weight of 1-2 x 105 and a content 15-35% vinyl acetate. 3. The composition of primers according to claim 1, in which this chlorinated polypropylene in which a grafted polymer of an unsaturated dicarboxylic acid and of polypropylene is subjected to a substitution of chlorine (B) has an average molecular weight of 6 x 104-105 and a chlorine content of 20 to 30%. 4. The primer composition according to claim 1, in which this grafted polymer of an unsaturated dicarboxylic acid and of an ethylene-ethyl acrylate copolymer (b) has a weight-average molecular weight of 5-15 x 104 and a ethyl acrylate content of 15% or less. 5. The primer composition as claimed in claim 1, in which this chlorination product of the grafted polymer of an unsaturated dicarboxylic acid and of an ethylene-vinyl acrylate copolymer (c) has a chlorine content of 10 to 25%. 6. A composition of primers according to claim 1, containing the following constituents: this grafted polymer of an unsaturated dicarboxylic acid and of an ethylene-vinyl acetate copolymer (a), approximately 2 to 30 parts by weight, this chlorinated polypropylene in which the grafted polymer of an unsaturated dicarboxylic acid and of polypropylene is subjected to a substitution of chlorine (B) approximately 0.5 to 25 parts by weight; a pigment (D) approximately 0 to 30 parts by weight, a solvent (C) approximately 40 to 99 parts by weight, and an organic titanium compound (I) approximately 0 to 5 parts by weight, the total being 100 parts by weight. 7. The composition of primers according to claim 1, containing the following constituents: this chlorinated polypropylene in which the grafted polymer of an unsaturated dicarboxylic acid and of the polypropylene is subjected to a substitution of chlorine (B) approximately 0.5 to 15 parts by weight, this grafted polymer of an unsaturated dicarboxylic acid and of an ethylene-ethyl acrylate copolymer (b) or the chlorination product of the grafted polymer (c) approximately 2 to 40 parts by weight, a pigment (D) approximately 0 to 30 parts by weight, a solvent (C) approximately 40 to 97.5 parts by weight, the total being 100 parts by weight. 8. A composition of primers according to claim 1, containing the following constituents: this grafted polymer of an unsaturated dicarboxylic acid and of an ethylene-vinyl acetate copolymer (a) approximately 1 to 30 parts by weight, this grafted polymer of an unsaturated dicarboxylic acid and of an ethylene-ethyl acrylate copolymer (b) or the chlorination product of the grafted polymer (c) from approximately 1 to 29.5 parts by weight, this chlorinated polypropylene in which the grafted polymer of an unsaturated dicarboxylic acid and of the polypropylene is subjected to a substitution of chlorine (B) approximately 0.5 to 15 parts by weight, a pigment (D) approximately 0 to 30 parts by weight, a solvent (C) approximately 40 to 97.5 parts by weight, the total being 100 parts by weight. 9. Composition of primers for the pretreatment of coatings comprising (A) at least one polymer chosen from a grafted polymer of an unsaturated dicarboxylic acid and an ethylene-vinyl acetate copolymer (a), a grafted polymer of an unsaturated dicarboxylic acid and an ethylene-acrylate copolymer d 'ethyl (b) or the product of the chlorination of the grafted polymer (c), (B) chlorinated polypropylene in which a grafted polymer of an unsaturated dicarboxylic acid and polypropylene is subjected to chlorine substitution (E) a chlorosulfonated polyethylene, (C) a solvent, and (F) a vulcanizing agent. 10. The primer composition as claimed in claim 9, in which this grafted polymer of an unsaturated dicarboxylic acid and of an ethylene-vinyl acetate copolymer (a) has an average molecular weight of 1 to 2 x 105 and an acetate content. 15 to 35% vinyl. 11. The composition of primers according to claim 9, in which this chlorinated polypropylene in which the grafted polymer of an unsaturated dicarboxylic acid and of polypropylene is subjected to a substitution of chlorine (B) has a weight average molecular weight of 6 ^ 10 x 10 "and a chlorine content of 20 to 30%. 31 5 10 15 20 25 30 35 40 45 50 55 60 CH 686 018G A3 12. The primer composition according to claim 9, in which this grafted polymer of an unsaturated dicarboxylic acid and of an ethylene-ethyl acrylate copolymer (b) has a weight-average molecular weight of 5-15 x 104 and a ethyl acrylate content of 15% or less. 13. A primer composition according to claim 9, in which this chlorination product of the grafted polymer of an unsaturated dicarboxylic acid and of an ethylene-ethyl acrylate copolymer (c) has a chlorine content of 10 to 25%. 14. The primer composition according to claim 9, in which this chlorosulfonated polyethylene has a weight-average molecular weight of 1- 2 x 105, a chlorine content of 25-35% and a sulfur content of 0.5-8, 5%. 15. A composition of primers according to claim 9, containing the following constituents: this grafted polymer of an unsaturated dicarboxylic acid and of an ethylene-vinyl acetate copolymer (a) approximately 1 to 20 parts by weight, this chlorinated polypropylene in which the grafted polymer of an unsaturated dicarboxylic acid and of the polypropylene is subjected to a substitution of chlorine (B) approximately 1 to 20 parts by weight, a chlorosulfonated polyethylene (E) approximately 3 to 40 parts by weight, a pigment (D) approximately 0 to 50 parts by weight, a vulcanizing agent (F) approximately 0 to 10 parts by weight, a vulcanization accelerator (G) approximately 0 to 5 parts by weight, an anti-aging agent (H) approximately 0 to 5 parts by weight, and a solvent (C) approximately 40 to 95 parts by weight, the total being 100 parts by weight. 16. A primer composition according to claim 9, containing the following constituents: this chlorinated polypropylene in which the grafted polymer of an unsaturated dicarboxylic acid and of the polypropylene is subjected to a substitution of chlorine (B) approximately 1 to 20 parts by weight, this grafted polymer of an unsaturated dicarboxylic acid and of an ethylene-ethyl acrylate copolymer (b) or the chlorination product of the grafted polymer (c) approximately 1 to 20 parts by weight, a chlorosulfonated polyethylene (E) approximately 3 to 40 parts by weight, a pigment (D) approximately 0 to 50 parts by weight, a vulcanizing agent (F) approximately 0 to 10 parts by weight, a vulcanization accelerator (G) approximately 0 to 5 parts by weight, an anti-aging agent (H) approximately 0 to 5 parts by weight, and a solvent (C) approximately 40 to 95 parts by weight, the total being 100 parts by weight. 17. A composition of primers according to claim 9, containing the following constituents: this grafted polymer of an unsaturated dicarboxylic acid and of an ethylene-vinyl acetate copolymer (a) approximately 1 to 15 parts by weight, this grafted polymer of an unsaturated dicarboxylic acid and of an ethylene-ethyl acrylate copolymer (b) or the chlorination product of the grafted polymer (c) approximately 1 to 15 parts by weight, this chlorinated polypropylene in which the grafted polymer of an unsaturated dicarboxylic acid and of the polypropylene is subjected to substitution by chlorine (B) approximately 1 to 15 parts by weight, a chlorosulfonated polyethylene (E) approximately 4 to 40 parts by weight, a pigment (D) approximately 0 to 50 parts by weight, a vulcanizing agent (F) approximately 0 to 10 parts by weight, a vulcanization accelerator (G) approximately 0 to 5 parts by weight, an anti-aging agent (H) approximately 0 to 5 parts by weight, and a solvent (C) approximately 40 to 93 parts by weight, the total being 100 parts by weight. 18. Composition of primers of the granulated type or of the powder type in the solid state at room temperature for the pretreatment of coatings, comprising: (A) at least one polymer chosen from a grafted polymer of an unsaturated dicarboxylic acid and of an ethylene-vinyl acetate copolymer (a), a grafted polymer of an unsaturated dicarboxylic acid and of an ethylene-ethyl acrylate copolymer (b) or a chlorination product of the grafted polymer (c), and (B) a chlorinated polypropylene in which a grafted polymer of an unsaturated dicarboxylic acid and polypropylene is subjected to substitution by chlorine. 19. Composition of primers of the granulated type or of the powder type in the solid state at room temperature according to claim 18, in which this grafted polymer of an unsaturated dicarboxylic acid and of an ethylene-vinyl acetate copolymer (a) has a weight average molecular weight of 1 to 2 x 105 and a vinyl acetate content of 15 to 35%. 20. Composition of primers of the granulated type or of the powder type in the solid state at room temperature according to claim 18, in which said chlorinated polypropylene in which a grafted polymer of an unsaturated dicarboxylic acid and of polypropylene is subjected to a substitution by chlorine (B) has a weight average molecular weight of 6 x 104-105 and a chlorine content of 20 to 30%. 21. A composition of primers of the granulated type or of the powder type in the solid state at room temperature according to claim 18, in which this polymer crimped with an unsaturated dicarboxylic acid and 32 5 10 15 20 25 30 35 40 45 50 55 60 65 CH 686 018G A3 of an ethylene-ethyl acrylate copolymer (b) has a weight average molecular weight of 5-15 x 104 and an ethyl acrylate content of 15% or less. 22. Composition of primers of the granulated type or of the powder type in the solid state at room temperature according to claim 18, in which this chlorinated product of the grafted polymer of an unsaturated dicarboxylic acid and of an ethylene-acrylate copolymer ethyl (c) has a chlorine content of 10 to 25%. 23. Composition of primers of the granulated type or of the powder type in the solid state at room temperature according to claim 18, containing the following constituents: this grafted polymer of an unsaturated dicarboxylic acid and of an ethylene-vinyl acetate copolymer (a) approximately 20 to 95 parts by weight, this chlorinated polypropylene in which the grafted polymer of an unsaturated dicarboxylic acid and of polypropylene is subjected to substitution by chlorine (B) approximately 5 to 60 parts by weight, and a pigment (D) approximately 0 to 50 parts by weight, the total being 100 parts by weight. 24. Composition of primers of the granulated type or of the powder type in the solid state at room temperature according to claim 18, containing the following constituents: this chlorinated polypropylene in which the grafted polymer of an unsaturated dicarboxylic acid and of polypropylene is subjected to a substitution by chlorine (B) approximately 5 to 60 parts by weight, this grafted polymer of an unsaturated dicarboxylic acid and of an ethylene-ethyl acrylate copolymer (b) or the chlorination product of the grafted polymer (c) approximately 20 to 95 parts by weight, and a pigment D approximately 0 to 30 parts by weight, the total being 100 parts by weight. 25. Composition of primers of the granulated type or of the powder type in the solid state at room temperature according to claim 18, containing the following constituents: this grafted polymer of an unsaturated dicarboxylic acid and of an ethylene-vinyl acetate copolymer (a) approximately 10 to 85 parts by weight, this grafted polymer of an unsaturated dicarboxylic acid and of an ethylene-ethyl acrylate copolymer (b) or the chlorination product of the grafted polymer (c) approximately 1 to 85 parts by weight, this chlorinated polypropylene in which the grafted polymer of an unsaturated dicarboxylic acid and of the polypropylene is subjected to a substitution by chlorine (B) approximately 5 to 60 parts by weight, and a pigment (D) approximately 0 to 50 parts by weight, the total being 100 parts by weight. 26. Composition of primers of the granulated type or of the powder type in the solid state at room temperature, for the pretreatment of coatings comprising: (A) at least one polymer chosen from a grafted polymer of an unsaturated dicarboxylic acid and of an ethylene-vinyl acetate copolymer (a), a grafted polymer of an unsaturated dicarboxylic acid and of an ethylene-ethyl acrylate copolymer (b) or of a product chlorinating the grafted polymer (c), (B) a chlorinated polypropylene in which a grafted polymer of an unsaturated dicarboxylic acid and a polypropylene is subjected to substitution by chlorine. (E) a chlorosulfonated polyethylene, and (F) a vulcanizing agent. 27. A composition of powder-type primers according to claim 26, in which this grafted polymer of an unsaturated dicarboxylic acid and of an ethylene-vinyl acetate copolymer (a) has a weight-average molecular weight of 1-2 x 105 and a vinyl acetate content of 15 to 35%. 28. A composition of powder type primers according to claim 26, in which the grafted polymer of an unsaturated dicarboxylic acid and of polypropylene is subjected to a substitution by chlorine (B) has a molecular weight by weight of 6-10 x 104 and a chlorine content of 20 to 30%. 29. Composition of powder type primers according to claim 26, in which this grafted polymer of an unsaturated dicarboxylic acid and of an ethylene-ethyl acrylate copolymer (b) has an average molecular weight a weight of 5-15 x 105 and an ethyl acrylate content of 15% or less. 30. A powder type primer composition according to claim 26, in which this chlorinated product of the grafted polymer of an unsaturated dicarboxylic acid and of an ethylene-ethyl acrylate copolymer (c) has a chlorine content of 10-25 %. 31. Composition of powder type primers according to claim 26, in which this chlorosulfonated polyethylene (E) has a weight average molecular weight of 1-2 x 105, a chlorine content of 25 to 35% and a sulfur content of 0.5-8.5%. 32. Composition of powder type primers according to claim 26, containing the following constituents: this grafted polymer of an unsaturated dicarboxylic acid and an ethylene-vinyl acetate copolymer (a) approximately 2.5 to 45 parts by weight, this chlorinated polypropylene in which the grafted polymer of an unsaturated dicarboxylic acid and of a polypropylene is subjected to a substitution by chlorine (B) approximately 2.5 to 45 parts by weight, a chlorosulfonated polyethylene (E) approximately 10 to 95 parts by weight, a pigment (D) approximately 0 to 50 parts by weight, 33 5 10 15 20 25 30 35 40 45 50 55 60 65 CH 686 018G A3 a vulcanizing agent (F) approximately 0 to 10 parts by weight, a vulcanization accelerator (G) approximately 0 to 5 parts by weight, and an anti-aging agent (H) approximately 0 to 5 parts by weight, the total being 100 parts by weight. 33. Composition of powder type primers according to claim 26 containing the following constituents: this chlorinated polypropylene in which the grafted polymer of an unsaturated dicarboxylic acid and of a polypropylene is subjected to a substitution by chlorine (B) chlorinated polypropylene in which a polypropylene is simply subjected to a substitution by chlorine approximately 2.5 to 45 parts by weight, this polymer grafted with an unsaturated dicarboxylic acid and an ethylene-ethyl acrylate copolymer (b) or the chlorination product of the grafted polymer (c) approximately 2.5 to 45 parts by weight, a chlorosulfonated polyethylene (E) approximately 10 to 95 parts by weight, a pigment (D) approximately 0 to 50 parts by weight, a vulcanizing agent (F) approximately 0 to 10 parts by weight, a vulcanization accelerator (G) approximately 0 to 5 parts by weight, and an anti-aging agent (H) approximately 0 to 5 parts by weight, the total being 100 parts by weight. 34. Composition of powder type primers according to claim 26, containing the following constituents: this grafted polymer of an unsaturated dicarboxylic acid and of an ethylene-vinyl acetate copolymer (a) approximately 2.5 to 30 parts by weight, this grafted polymer of an unsaturated dicarboxylic acid and of an ethylene-ethyl acrylate copolymer (b) or the chlorination product of the grafted polymer (c) approximately 2.5 to 30 parts by weight, this chlorinated polypropylene in which the grafted polymer of an unsaturated dicarboxylic acid and of a polypropylene is subjected to a substitution of chlorine (B) approximately 2.5 to 30 parts by weight, a chlorosulfonated polyethylene (E) approximately 10 to 92.5 parts by weight, a pigment (D) approximately 0 to 50 parts by weight, a vulcanizing agent (F) approximately 0 to 10 parts by weight, a vulcanization accelerator (G) approximately 0 to 5 parts by weight, and an anti-aging agent (H) approximately 0 to 5 parts by weight, the total being 100 parts by weight. 35. Method for treating primers according to any one of claims 1 to 34, in which far infrared rays are used as heating means in the treatment of surface activity. 34