JPH0820678A - Resin composition and automotive parts - Google Patents

Abstract

PURPOSE:To obtain a resin composition capable of being formed into a film, a sheet, a plate and other shape by an ordinary forming method wherein each of the obtained formed articles is excellent in coating property, adhesion, coating film adhesivity and printability and especially useful for automotive parts because it can give automotive parts having improved coating property without lowering forming characteristics and mechanical strength of the formed article. CONSTITUTION:This resin composition is obtained by compounding 100 pts.wt. of olefin polymer containing 15-80wt.% of an elastomer component with 0.1-30 pts.wt. of a modified polyhydroxyhydrocarbon polymer obtained by reacting (A) a polyhydroxyhydrocarbon polymer having a number average molecular weight of 500-20000 with (B) a compound having a functional group reactive with a hydroxyl group and a polymerizable unsaturated group in a molecule.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition having improved adhesiveness and coating film adhesion and an automobile member using the same.

[0002]

2. Description of the Related Art Conventionally, olefin-based resins have been widely used as members for automobiles, and these olefin-based resins are usually coated when used as members for automobiles. However, since the olefin resin does not have a polar group in its structure, it is known that the adhesive force of the paint is weak when it is applied and the adhesive force of the adhesive is weak when it is adhered. Therefore, in order to improve the poor adhesion and adhesiveness, the surface of the olefin resin member is washed with trichloroethane vapor and then a primer is applied,
The surface has been modified by plasma treatment or the like. However, such a coating method has conventionally had the following problems.

That is, in the trichloroethane vapor cleaning, the influence of the trichloroethane vapor on the working environment is great, and the use of trichloroethane will not be possible in the future due to the regulation of the use of trichloroethane. Further, the primer coating will be performed by using an expensive primer. Since the number of processes is increased, there is a drawback that the coating cost becomes high. On the other hand, in the plasma processing method, expensive equipment must be used,
Since it is a batch system, there is a problem that the cost is inevitable.

In recent years, many olefin resin compositions having improved coatability have been proposed for the purpose of omitting these treatments. For example, JP-A-3-157168 and the like describe that a composition obtained by adding a diene polymer having a hydroxyl group at the terminal to an elastomer-containing polyolefin has improved adhesiveness with a coating material. Furthermore, JP-A-4-103
640 proposes blending a hydroxyl group-containing ethylene copolymer and a carboxyl group-containing copolymer with an elastomer-containing polyolefin. However, with these compositions, the adhesiveness to the paint was not yet sufficient.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide an olefin resin composition having improved moldability and mechanical strength, and improved adhesiveness with a paint so that trichloroethane cleaning and primer treatment can be omitted, and the same. The object is to provide an automobile member using the.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted extensive studies for the above-mentioned purpose, and as a result, found that the use of a diene polymer having a terminal modified can improve the coating property, and reached the present invention. did. That is, the gist of the present invention is that, with respect to 100 parts by weight of an olefin polymer containing 15 to 80% by weight of an elastomer component, a polyhydroxy hydrocarbon polymer (A) having a number average molecular weight of 500 to 20000 and a molecule are used. The modified polyhydroxy hydrocarbon polymer obtained by reacting a functional group having reactivity with a hydroxyl group with a compound (B) having a polymerizable unsaturated group is 0.1
-30 parts by weight of the resin composition, and an automobile member having a coating film directly formed on the surface of a molded article of the resin composition.

Hereinafter, the present invention will be described in detail. The olefin polymer in the present invention is not particularly limited to this, but specifically, ethylene, propylene,
Α-olefin homopolymers typified by butene-1,3-methyl-butene-1,4-methylpentene-1 and the like,
Alternatively, a copolymer may be used.

As polyethylene, a low-density homopolymer having a large number of long-chain branches produced by a high-pressure method, a copolymer of ethylene and vinyl acetate, acrylic acid, methacrylic acid, acrylate, methacrylate or the like, or a low-pressure method is produced. Examples thereof include a high-density polyethylene or a copolymer of ethylene and another olefin, and a high-density polyethylene or a copolymer of ethylene and another olefin by a medium pressure method.

The polypropylene includes stereoregular polypropylene, that is, isotactic polypropylene, syndiotactic polypropylene, and atactic polypropylene. As a polymer of an olefin higher than propylene, there is a polymer of butene-1, which is also included from a highly stereoregular crystalline polymer to an amorphous polymer. Examples of higher olefin polymers include poly-4-methylpentene-1. In addition, various olefin polymers are used without limitation on the type of α-olefin.

Copolymers of ethylene and propylene, ethylene and butene-1, ethylene and hexene-1, etc. may also be used. In this case, either a random copolymer or a block copolymer may be used, and a terpolymer may also be used. included. Further, divinylbenzene, vinylsilane, and unsaturated carboxylic acid may be copolymerized in a range that does not significantly impair the effects of the invention, for example, 30% by weight or less, preferably 15% by weight or less.

Further, a mixture or alloy of these may be used. Considering the use as a member for automobiles, high moldability and high mechanical strength are required. Therefore, the melt flow rate (MFR) is determined by ASTM-D12.
The value measured according to 38 is 0.01 to 200 g / 10
Min, preferably 0.1 to 100 g / 10 min, particularly preferably 0.5 to 50 g / 10 min, and the bending elastic modulus is 1000 in accordance with JIS-K7203.
~ 25000 Kg / cm〓, preferably 2000-20
An olefin polymer having a range of 000 kg / cm 2 is preferably used. Particularly, an ethylene-propylene copolymer is preferable, and among them, a copolymer having an ethylene content of 1 to 40% by weight is preferable.

The above-mentioned elastomer component contained in the olefin polymer is a copolymer of α-olefin such as ethylene, propylene, butene-1, pentene-1 or the like from the viewpoint of compatibility with the olefin polymer. And a diene copolymer is preferred. These copolymers are J
The initial elastic modulus measured according to IS-K6301 is 40.
It is preferably 0 Kg / cm 〓, preferably 200 Kg / cm 〓 or less and amorphous or low crystalline. Specifically, ethylene-propylene copolymer rubber and ethylene-propylene-diene copolymer rubber are preferable.

The content of the elastomer component is 15 to 80% by weight. If it is less than 15% by weight, the impact resistance required for automobile parts is particularly poor, which is not desirable. On the other hand, 80
If it exceeds the weight%, blocking tends to occur. The modified polyhydroxy hydrocarbon polymer used in the present invention comprises a polyhydroxy hydrocarbon polymer (A) having a number average molecular weight of 500 to 20,000 and a functional group having reactivity with a hydroxyl group in one molecule. It is obtained by reacting with a compound (B) having both a polymerizable unsaturated group. The ratio of the functional group having reactivity with the polyhydroxy hydrocarbon polymer (A) and the compound having a polymerizable unsaturated group (B) is preferably the hydroxyl equivalent of (A) is A, (B). B is the functional group equivalent having reactivity with the hydroxyl group of 1.
It is obtained by reacting (A) and (B) under the condition of 5 or more.

The polyhydroxy hydrocarbon polymer as the component (A) has at least one hydroxyl group per molecule and has a number average molecular weight of 500 to 200.
00, a structure of the main chain is a hydrocarbon, preferably an iodine value of 100 or less, and a liquid or brittle wax at room temperature. Examples of such polyhydroxy hydrocarbon polymers include hydrogenated products of polyhydroxydiene compounds, hydrogenated products of oxidative decomposition reduction products of isobutylene-diene monomer copolymers, α
Examples thereof include hydrogenated products of oxidative decomposition reduction products of non-conjugated diene (or conjugated diene) copolymers such as -olefins (for example, ethylene, propylene, etc.). Of these, hydrogenated products of polyhydroxydiene-based polymers are particularly preferable.

Thus, the polyhydroxydiene polymer is produced by a well-known method using a conjugated diene or a conjugated diene and a vinyl monomer as a raw material, for example, a radical polymerization method or an anionic polymerization method. In the case of radical polymerization, a conjugated diene polymer or copolymer having a hydroxyl group at the terminal can be directly obtained by polymerizing with hydrogen peroxide as a polymerization initiator, but in the case of anionic polymerization, an alkali metal is first bonded to the terminal by using an anionic polymerization catalyst. A living polymer having the above structure is produced and then reacted with a monoepoxy compound, formaldehyde and the like. As the raw material conjugated diene, 1,3-butadiene, isoprene, chloroprene and the like can be used. Examples of the copolymerization component include vinyl monomers such as styrene, acrylonitrile, methyl (meth) acrylate and vinyl acetate. The amount of the copolymerization component used is preferably 30% by weight or less of the total amount of monomers.

The hydrogenation in the production of the hydrogenated product of the polyhydroxydiene copolymer is carried out by a conventional method using a catalyst such as nickel, cobalt, platinum, palladium, ruthenium or rhodium alone or by supporting it on a carrier. Therefore, it may be carried out under hydrogen. A polymer obtained by partially hydrogenating a polyhydroxydiene-based copolymer can also be used.

As another method for producing a polyhydroxy hydrocarbon polymer, there may be mentioned a method in which a copolymer of an α-olefin and another monomer is subjected to oxidative decomposition treatment and then reduced. For example, isobutylene and butadiene or 1,3
Polyhydroxyisobutylene can be obtained by subjecting a butyl rubber polymer obtained by cationically polymerizing pentapentene to ozonolysis and then reducing with lithium aluminum hydride. Further, by reacting these polyhydroxy hydrocarbons with diisocyanate or diester,
It can also be used as a high molecular weight polyhydroxy hydrocarbon.

In the present invention, a part of the polyhydroxy hydrocarbon polymer may be replaced with another polyol. Examples of other polyols include polyethylene glycol, polypropylene glycol, polyalkylene glycols such as polytetramethylene glycol, polycaprolactone polyols, castor oil, ethylene glycol, lower polyols such as trimethylolpropane, or trimethylolpropane and ethylene oxide. And the like. The substitutable amount is 0 to 49% by weight of the polyhydroxy hydrocarbon polymer. When it exceeds this range, the hydrolysis resistance, light resistance and heat resistance which are the characteristics of the polyhydroxy hydrocarbon polymer are deteriorated, which is not preferable.

Next, the compound (B) having both a functional group reactive with a hydroxyl group and a polymerizable unsaturated group in the molecule used in the present invention has a reactivity with a hydroxyl group in one molecule. It is a compound having both a functional group and a polymerizable unsaturated group. Here, the polymerizable unsaturated group means an ethylenically unsaturated group capable of radical polymerization, anionic polymerization, cationic polymerization and the like, and specifically, a styryl group, an α-methylstyryl group, a vinyl ether group, a vinyl ester group. , (Meth) acrylic groups, allyl groups and the like. The group having reactivity with a hydroxyl group is a functional group having reactivity with the hydroxyl group of the component (A), and more specifically, an isocyanate group, a carboxyl group or a group derived from a carboxyl group is preferable. It is an example.

Specific examples of the compound (B-1) having both a polymerizable unsaturated group and an isocyanate group in one molecule are:

[0021]

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And the like. Of these, the preferred one is

[0023]

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It is Another example of the compound having both a polymerizable unsaturated group and an isocyanate group in the molecule is 1
A reaction product of a compound having a polymerizable unsaturated group and a hydroxyl group in the molecule and a diisocyanate compound is also included. Representative examples of the compound having a polymerizable unsaturated group and a hydroxyl group in one molecule include hydroxyalkyl (meth) acrylates such as 2-hydroxyethyl (meth) acrylate and 4-hydroxybutyl (meth) acrylate. Examples of the diisocyanate compound include tolylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate and xylylene diisocyanate. Here, the reaction of a compound having a polymerizable unsaturated group and a hydroxyl group in one molecule with a diisocyanate compound is given as an example, but the reaction produces a compound having both a polymerizable unsaturated group and an isocyanate group in one molecule. However, the present invention is not limited to these.

Specific examples of the compound (B-2) having both a polymerizable unsaturated group and a carboxyl group or a functional group derived from a carboxyl group in one molecule include vinyl benzoic acid and (meth) acrylic acid. Unsaturated carboxylic acids such as
(Meth) acrylic acid esters such as methyl (meth) acrylate, ethyl (meth) acrylate, (meth) acrylic acid halides such as (meth) acrylic acid chloride, (meth) acrylic acid bromide, maleic anhydride, etc. And unsaturated acid anhydrides thereof. Among these, methyl (meth) acrylate and (meth) acrylic acid chloride are preferable.

The components (A) and (B) have A / B = 1.5 or more, where A is the hydroxyl group equivalent of (A) and B is the functional group equivalent of the hydroxyl group of (B). It is preferable to react at an equivalence ratio. If this equivalent ratio is less than 1.5, the proportion of the polyfunctional component in the component (A) to react with the component (B) increases, and the polyfunctional component in the resulting polymer composition also increases. If it is attempted to copolymerize this with other monomers using this as a raw material, it becomes very easy to gel.

The reaction between the component (A) and the component (B-1) is a urethane-forming reaction, and is carried out at a temperature of from room temperature to 120 ° C.
It can be suitably performed in a time of about 0 minutes to 24 hours. If necessary, a solvent such as toluene may be used in the reaction, or a catalyst such as dibutyltin dilaurate may be used.
The reaction between the component (A) and the component (B-2) is an ester formation reaction, and when (B-2) is an unsaturated carboxylic acid, a (meth) acrylic acid ester or an unsaturated acid anhydride, a mineral acid is used. , An acid catalyst such as paratoluene sulfonic acid, or a metal catalyst such as titanium alkoxide, zinc acetate, antimony oxide, etc., while removing the elimination component as necessary, at room temperature to 200 ° C. for 30 minutes to It can be suitably performed in about 24 hours. When (B-2) is a (meth) acrylic acid halide, a base such as triethylamine or pyridine is used, or an acid halide generated by flowing an inert gas stream is removed while the temperature is from room temperature to 150 ° C. , 30
It can be suitably performed in a time of about minutes to 24 hours. In these reactions, a solvent such as toluene may be used if necessary.

The modified polyhydroxy hydrocarbon-based polymer thus obtained is blended with the above-mentioned olefin-based polymer, but the method is not particularly limited. As the mixing device, a Brabender plastograph, a single-screw or twin-screw extruder, a powerful screw type kneader, a Banbury mixer kneader, a conventionally known kneader such as a roll, etc. are used, and the mixing temperature depends on the type of raw material. , For example 160 for polypropylene
It is desirable to carry out at 250 ° C.

The mixing ratio varies depending on the olefin polymer used and the intended use, but usually the olefin polymer 100 is used.
0.1 to 30 parts by weight, preferably 0.5
~ 15 parts by weight. Although the constituent requirements of the resin composition of the present invention have been described above with reference to preferred examples, the resin composition may contain the following additional components in addition to the above essential components within a range that does not significantly impair the effects of the present invention. It can be included. Such additional components include styrene-based and acrylic-based elastomers, inorganic fillers, specifically natural silica such as quartz, wet process, synthetic silica produced by a dry process, kaolin, mica, talc,
Natural silicates such as asbestos, synthetic silicates such as calcium silicate and aluminum silicate, layered clay minerals such as montmorillonite, metal hydroxides such as magnesium hydroxide and aluminum hydroxide, metal oxides such as alumina and titania, calcium carbonate , Metal powders such as aluminum and bronze, fibers such as glass fiber and carbon fiber, carbon black, potassium titanate, calcium sulfate, zinc oxide,
Examples include whiskers such as silicon nitride, sapphire, beryllia, boron carbide, and silicon carbide. In addition, other additives,
Specifically, colorants, stabilizers, dispersion aids, molecular weight modifiers,
A cross-linking agent, a cross-linking aid, a crystal nucleating agent and the like can be mentioned.

The resin composition of the present invention can be formed into a film shape, a sheet shape, a plate shape or another shape by a usual molding method, that is, a molding method such as injection molding, compression molding, extrusion molding (sheet molding, blow molding). It can be molded, but injection molding is preferred. The molded product has extremely good paintability, adhesiveness, coating film adhesion, and printability. In particular, when it is used as a member for automobiles, it is particularly effective because the moldability and the coatability are improved without lowering the mechanical strength of the molded product.

In the case of automobile members and the like, the coating material is directly applied to the surface of the molded article obtained by the above-mentioned molding method to form a coating film on the surface. As a coating method for forming a coating film, a conventional coating process can be adopted by removing the primer coating process. Also, the plasma treatment step can be omitted. An auxiliary surface treatment such as degreasing treatment before coating the coating material may be performed.

The degreasing treatment is generally carried out immediately before the coating treatment in order to remove dusts, process oils and the like that inevitably adhere to the surface of the molded product. Specifically, an organic solvent solution or its vapor,
A cleaning method using water, steam, an acid, an alkaline solution, a surfactant or the like is adopted. As a means for applying the coating material, conventionally known coating methods such as spray coating, brush coating and roller coating can be adopted.

As the paint, a paint that is often used,
For example, various paints such as acrylic, epoxy, polyester, urethane, alkyd, melamine, and fluorine can be used. Of these, acrylic, melamine, urethane, and polyester coatings are preferably used. The coated automotive member of the present invention has a coating material usually applied in a thickness of 10 to 100 μm, preferably 15 to 70 μm, and the coating film adheres firmly, so that sufficient coating performance as an automobile member is obtained. And also has mechanical strength. Automotive parts include fenders, door panels,
Bumper, spoiler, mudguard, side molding,
Wheel caps, instrument panels and the like are preferable examples.

[0034]

EXAMPLES Next, the present invention will be specifically described with reference to examples, but the present invention is not limited to these examples as long as the gist thereof is not exceeded. In the examples below,
The number average molecular weight is a value in terms of polystyrene by the GPC method.

In the following examples and comparative examples, a propylene homopolymer as an olefin resin (Mitsubishi Chemical Co. 45
00J, MFR = 9), ethylene-propylene-diene copolymer rubber (EP57P manufactured by Japan Synthetic Rubber Co., iodine value = 15, Mooney viscosity = as olefin elastomer.
88) and 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne-3 (Perhexin 25B, manufactured by NOF CORPORATION) as a crosslinking agent. As modified polyhydroxy hydrocarbon polymers, the following Reference Examples 1 to 4 are given.
What was adjusted by the method of was used.

Reference Example 1 In a flask equipped with a nitrogen inlet, polytail HA (manufactured by Mitsubishi Kasei Co., Ltd., hydrogenated product of polydiene compound having a hydroxyl group at the terminal, number average molecular weight of 2000, as a polyhydroxy hydrocarbon polymer, Hydroxyl equivalent 0.934 meq / g, iodine value 3.8) 470 g,
Takenate TMI (manufactured by Takeda Pharmaceutical Co., Ltd., m-isopropenyl-α, α-dimethylbenzyl isocyanate,
Isocyanate group equivalent 4.845 meq / g) 30 g
(Equivalent to hydroxyl equivalent / isocyanate equivalent = 3/1), UL-22 (manufactured by Mitsubishi Kasei Dow Co., Ltd., tin catalyst)
After charging 0.015 g and replacing the inside of the flask with nitrogen,
The product was obtained by reacting with a nitrogen blanket at 60 ° C. for 6 hours.
The completion of the reaction was confirmed by IR by the disappearance of absorption of the isocyanate group near 2250 cm −1.
Similarly, absorption of carbon-carbon double bond was observed at 1620 cm −1 by IR, and it was confirmed that a polymerizable unsaturated group was introduced. The number average molecular weight of the product was 2200.

Reference Example 2 466 g of Polytail HA,
MOEI (manufactured by Kokusan Kagaku Co., Ltd., instead of Takenate TMI)
A product was obtained in the same manner as in Reference Example 1, except that 34 g of methacroylethyl isocyanate and an isocyanate group equivalent of 6.445 meq / g (hydroxyl group equivalent / isocyanate group equivalent = 2/1) were used. The number average molecular weight of the product is 24
It was 00.

Reference Example 3 457 g of polytail HA,
A product was obtained in the same manner as in Reference Example 1 except that the amount of Takenate TMI was 30 g (hydroxyl equivalent / isocyanate equivalent = 2/1). Confirmation of completion of the reaction and introduction of the polymerizable unsaturated group was carried out in the same manner as in Reference Example 1. The number average molecular weight of the product was 2300.

(Examples 1 to 3, Comparative Examples 1 to 4) Table 1 below.
The components shown in (2) were melt-kneaded at 180 ° by a twin-screw extruder to form pellets. Using this pellet, a flat plate and a three-point bending elastic modulus test piece were injection molded under the following conditions. Molding conditions Molding machine: Toshiba IS80EPN-2A injection molding machine Molding temperature: 210 ° C Molded product: Flat plate (120 x 120 x 2 mm) Three-point bending elastic modulus test piece (128 x 12.5 x 6.4 m)
m) A neutral detergent solution for household use (Mama Lemon, trade name manufactured by Lion Corporation, 0.15% aqueous solution for 3 minutes, and distilled water for 6 minutes)
After washing for a minute, water on the surface was wiped off and left for 12 hours at room temperature to complete degreasing treatment, and this was used as a sample for painting.

The following three types of two-component acrylic urethane-based paints were applied to this product by an air spray gun so that the coating film thickness was 40 μm. afterwards,
It was baked and dried at 80 ° C. for 30 minutes. , Painted. Paint 1 White (manufactured by Nippon Paint Co., Ltd., product name Superior FII) Paint 2 Silver Metallic (manufactured by Nippon Paint Co., Ltd., product name Superior FII) Paint 3 Black (manufactured by Nippon BPI Chemical Co., Ltd.) It was

Using a single-edged razor, 11 vertical and horizontal parallel lines running perpendicular to the surface of the test piece are drawn at 1 mm intervals to make 100 cross-cuts. Cellophane adhesive tape (JIS
-Z1522) was sufficiently pressure-bonded, kept at about 30 degrees from the coating surface and peeled off at once in front, the state of the part surrounded by the cross-cuts was observed, and the number of cross-cuts not peeled was recorded. The results are shown in Table 1 below.

[0042]

[Table 1] Table 1 ---------------------------------------------------- Comparative Comparison Comparative Comparison Comparative Implementation Example Example 1 Example 2 Example 3 Example 4 Example 1 Example 2 Example 3 −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− Olefin 50 30 30 30 50 30 30 parts by weight Resin Olefin 50 70 70 70 50 70 70 〃 Elastomer cross-linking agent 0.31 0.43 0.43 0.43 0.31 0.43 0.43 〃 Porretail HA--3 6--〃 Reference Example 1 Reference Example 2 Reference Example 3 Modified retail----3 3 6 〃 Paint 1 19 41 92 57 97 100 100 paint 2 31 69 83 67 100 100 100 paint 3 51 72 94 84 99 100 100 flexural modulus 1140 1120 3940 1120 1130 ASTM D790 compliant −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−

[0043]

The resin composition of the present invention can be molded into a film shape, a sheet shape, a plate shape and other shapes by a usual molding method, and the molded product has coatability, adhesiveness and coating adhesion. And printability are extremely good. In particular, when it is used as an automobile member, it is particularly effective because the coatability is improved without lowering the moldability and the mechanical strength of the molded product.

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Claims (5)

[Claims] 1. A polyhydroxy hydrocarbon polymer (A) having a number average molecular weight of 500 to 20,000 and a hydroxyl group in the molecule based on 100 parts by weight of an olefin polymer containing 15 to 80% by weight of an elastomer component. On the other hand, 0.1 to 30 parts by weight of a modified polyhydroxy hydrocarbon polymer obtained by reacting a reactive functional group with a compound (B) having a polymerizable unsaturated group is blended. A characteristic resin composition. 2. The resin composition according to claim 1, wherein the functional group having reactivity with a hydroxyl group is an isocyanate group, a carboxyl group or an ester-forming derivative group thereof. 3. The elastomer component is a copolymer of ethylene and α-olefin or ethylene, α-olefin,
The resin composition according to claim 1, which is a terpolymer of a diene. 4. The resin composition according to claim 1, wherein the olefin polymer is a homopolymer or a copolymer of ethylene or another α-olefin. 5. An automobile member having a coating film directly formed on the surface of a molded product of the resin composition according to claim 1.