JP4417156B2 - Manufacturing method of automobile flocking product based on olefin resin - Google Patents

Description

  The present invention relates to a method for producing an automotive flocking product such as a weatherstrip. Specifically, after laminating a surface-modifying resin comprising a polymer having a SP value of 7 to 10 and a photopolymerization initiator on an olefin-based resin and irradiating light, the isocyanate group-containing urethane prepolymer is a main component and the melting point is 40. The present invention relates to a method for producing an automobile flocking product based on an olefin-based resin in which a pile is electrostatically flocked using a moisture-curable reactive hot melt adhesive having a temperature of from 150 ° C. to 150 ° C.

  In recent years, in the housing industry, the problem of sick house (indoor air pollution) due to formaldehyde, toluene, xylene, etc. contained in building materials, construction materials and insect repellents has been emphasized. The provisional guideline value of (TVOC) was shown. According to the results of the VOC measurement in the new car, the National Life Center told the automobile industry that “TVOC generated from the new car increased its concentration as the temperature inside the car increased, exceeding the guideline value for indoor concentration established by the Ministry of Health, Labor and Welfare. "We want to build a car that minimizes the use of volatile chemicals as much as possible." Due to this social background, the automobile industry has begun to review pollution caused by chemical substances in the passenger compartment and make improvements in accordance with the guidelines set by the Ministry of Health, Labor and Welfare.

  On the other hand, with the goal of reducing the weight of members and reducing the environmental burden, products that have been manufactured with steel or vinyl chloride resin have been replaced with polyolefin resins. Low-activity resins such as polypropylene elastomer and polyethylene elastomer (TPO) in which rubber components such as EPDM components are added to those resins are inexpensive and relatively high in strength, so that they can be used for weather strips, bumpers, instrument panels, etc. Application to automotive parts is in progress.

  However, since the polyolefin resin generally has insufficient adhesion to the adhesive, it is necessary to perform a treatment for increasing the adhesion to the adhesive in order to implant the surface of the polyolefin resin substrate. It was. As a conventional technique, a primer treatment method in which a corona discharge treatment, a surface treatment by plasma discharge, a chlorinated polypropylene, or the like is applied to the surface of a substrate has been studied.

  In addition, a method of performing ultraviolet irradiation after contacting with an ultraviolet absorbing solvent as disclosed in JP-A-64-9243, and photoinitiators as disclosed in JP-A-5-271444 and JP-A-6-336575 are included. There has also been proposed a method for modifying a substrate surface by applying ultraviolet irradiation, such as a method of applying an ultraviolet ray after applying a solution to the substrate surface.

A solvent-type urethane adhesive has been reported as an electrostatic flocking adhesive for a substrate made of an olefin resin used in combination with an organic solvent-based chlorinated polypropylene primer.
JP-A 64-009243 JP 05-271444 A Japanese Patent Laid-Open No. 06-336575

  However, there are the following problems in applying these methods to general purposes.

  To perform corona discharge or plasma discharge, expensive special equipment is required. Furthermore, since the modified effect such as adhesiveness attenuates with time, there is a problem that the adhesive property, which is the purpose of the modification, varies with time and stable performance cannot be obtained. In addition, the above method has a small modification effect on polyolefin elastomers such as TPO, and does not exhibit sufficient adhesiveness.

  Since a chlorinated polypropylene primer dissolved in an organic solvent is applied to the surface of the base material, it is not preferable from the viewpoint of VOC regulations and the like on the global environment, the working environment, and the interior environment of the vehicle which is regarded as a problem in the present invention.

  Similarly, the organic solvent is used for the contact with the ultraviolet absorbing solvent and the application of the solution containing the photoinitiator, which causes a VOC problem.

  As for the adhesive, since the solvent-type urethane-based adhesive contains a large amount of solvent, there is a problem in terms of VOC.

  An object of the present invention is to solve the above-mentioned drawbacks and improve the electrostatic flocking property of the substrate surface made of olefin resin by a method with high productivity, and a method for producing an automobile flocking product based on olefin resin. Is to provide.

  The inventors of the present invention have intensively studied a reforming method for solving the above-mentioned problems and completed the present invention. That is, according to the first invention of the present invention, a coating layer of a surface-modifying resin comprising a polymer having an SP value of 7 to 10 and a photopolymerization initiator is formed on a substrate comprising an olefin resin, After irradiation with light, a moisture curable reactive hot melt adhesive having an isocyanate group-containing urethane prepolymer as a main component and a melting point of 40 ° C. or higher and 150 ° C. or lower was applied thereon, thereby forming A method for producing an automobile flocking product based on an olefin-based resin characterized in that a pile is electrostatically flocked on an adhesive layer. The second invention is a polymer having an SP value of 7 to 10 of the first invention is chlorine. A method for producing a flocking product for automobiles, characterized in that it is a polyolefin, and the third invention is an automatic characterized in that the polymer having an SP value of 7 to 10 according to the first invention is an acid-modified polyolefin. Is a manufacturing method of use flocking products.

  A surface modification resin coating layer composed of a polymer having an SP value of 7 to 10 and a photopolymerization initiator is formed on a base material made of an olefin resin, and the moisture curing reaction is performed after irradiating the coating layer with light. Electrostatic flocking with a conductive hot melt adhesive can provide superior wear resistance compared to no treatment, and superior wear resistance compared to plasma irradiation and corona discharge. Obtainable.

  In addition, by adopting a solvent-free, moisture-curing reactive hot melt adhesive as the adhesive, problems such as deterioration of working environment and utility costs when drying the solvent are improved compared to conventional solvent-based adhesives. can do.

Olefin-based resin The olefin-based resin constituting the substrate in the present invention includes ethylene, propylene, 1-butene, 3-methyl-1-butene, 4-methyl-1-pentene, 1-hexene, 1-pentene and the like. , Preferably a homopolymer of an α-olefin having 2 to 6 carbon atoms, a copolymer having two or more of these α-olefins as constituent monomers, or another copolymerizable monomer with the α-olefin. Specifically, polyethylene, polypropylene (including any of isotactic, syndiotactic, and atactic. The same shall apply hereinafter), poly-1-butene, and poly-4-methyl-1-pentene. Hard polyolefin materials such as; ethylene-propylene copolymer rubber; ethylene-propylene-diene copolymer rubber (EPDM) and the above hard polyolefin Examples thereof include a polyolefin elastomer (TPO) in which an ethylene-propylene copolymer rubber or EPDM is blended with a fin material.

  If desired, the base material of the olefin resin in the present invention may contain other resin components, additives, and fillers. Examples of the other resin components include styrene resins, styrene elastomers, and ethylene methacrylic acid resins. And ethylene vinyl acetate resin.

  A preferred ratio of the olefin resin component contained in the olefin resin substrate in the present invention is 50 wt% or more, and more preferably 60 wt% or more.

○ Polymer having SP value of 7 to 10 The resin component of the resin for surface modification of the present invention preferably has a higher affinity for the olefin resin to be modified, and a polymer having an SP value of 7 to 10 is preferable. Specific examples are described below, but the present invention is not limited to these.
(I) Rigid polyolefin: Polyethylene, polypropylene (including any of isotactic, syndiotactic, and atactic; the same applies hereinafter), poly-1-butene, poly-4-methyl-1-pentene, and the like.
(Ii) Polyolefin Elastomer: Examples include ethylene propylene rubber, EPDM, and polyolefin elastomer (TPO) in which ethylene propylene rubber or EPDM is blended with the hard polyolefin.
(Iii) Chlorinated polyolefin: Chlorinated polyethylene, chlorinated polypropylene, chlorinated ethylene-propylene copolymer, chlorinated ethylene-vinyl acetate copolymer, maleic anhydride modified chlorinated polypropylene, acrylic acid modified chlorinated polypropylene, anhydrous Examples include maleic acid-acrylic acid-modified chlorinated polypropylene.
(Iv) Acid-modified polyolefin: In addition to the above-mentioned acid-modified chlorinated polyolefin, maleic anhydride-modified polyethylene, maleic anhydride-modified polypropylene, acrylic acid-modified polypropylene, methacrylic acid-modified polypropylene, maleic anhydride-acrylic acid-modified polypropylene, etc. Can be mentioned.
(V) Other resins: Styrene resin, styrene elastomer, ethylene methacrylic acid resin, ethylene vinyl acetate resin and the like.

  The proportion of the olefin component contained in the polymer having an SP value of 7 to 10 used in the present invention is preferably 50 wt% or more, more preferably 60 wt% or more.

  A polymer having an SP value of less than 7 and a polymer larger than 10 cannot be used because of low affinity for olefin resins, poor wettability to olefin resins, and high adhesion cannot be obtained.

In the present invention, the SP value is the Fedors method [Polym. Eng. Sci. 14 (2), 152 (1974)] indicates the solubility parameter calculated from the molecular structural formula, and is represented by the square root [cal / cm ³ ] ^1/2 of the cohesive energy density.

  The chlorine content of the chlorinated polyolefin of the present invention is preferably 1 wt% or more and 60 wt% or less, more preferably 1 wt% or more and 50 wt% or less.

  When the chlorine content is less than 1 wt% or more than 60 wt%, the adhesion of the polyolefin resin to the adhesive is lowered. The reason is presumably that when the chlorine content is low, the wettability of the chlorinated polyolefin to the adhesive decreases, and when the chlorine content is high, the wettability of the chlorinated polyolefin to the polyolefin resin decreases. .

○ Photopolymerization initiator The photopolymerization initiator used in the present invention may be either a hydrogen abstraction type or a photocleavage type. Specifically, benzophenone, parachlorobenzophenone, 4-methylbenzophenone, 2,4,6-trimethylbenzophenone, 4-methoxybenzophenone, methyl 2-benzoylbenzoate, benzophenone sulfide, bis (4-dimethylaminophenyl) ketone, Hydrogen abstraction compounds such as anthraquinone, 2-ethylanthraquinone, benzyl, acetophenone, p-dimethylaminoacetophenone, pt-butyldichloroacetophenone, thioxanthone, 2,3-diethylthioxanthone, chlorothioxanthone, camphorquinone, 2-hydroxy- 2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2,2-dimethoxy-1,2-diphenylethane-1-one, 2-methyl 1 [4- (methylthio) phenyl] -2-morpholinopropan-1-one, benzoin alkyl ketal, benzylmethyl ketal, 2,2-diethoxyacetophenone, bis (2,4,6-trimethylbenzoyl) -phenylphos Examples of the photocleavable compound include, but are not limited to, fin oxide and 2,4,6-trimethylbenzoyldiphenylphosphine oxide.

  In the present invention, the amount of the photoinitiator added to the surface modifying resin is 0.1 to 200 parts by weight, preferably 0.2 to 120 parts by weight, based on 100 parts by weight of the resin. When the amount of photoinitiator is small, a sufficient modification effect cannot be obtained even when irradiated with light (ultraviolet rays), and when the amount is large, no further modification effect can be obtained. The affinity of the modifying resin to the olefin resin is reduced, and the modification effect is reduced.

Method for preparing surface modifying resin The method for preparing the surface modifying resin of the present invention is described below, but is not limited thereto.

(I) Preparation of solvent-type surface-modified resin composition It can be obtained by dissolving a polymer having an SP value of 7 to 10 and a photopolymerization initiator in an organic solvent such as toluene.

(Ii) Preparation of Solid Surface Modified Resin Composition It can be obtained by kneading a polymer having an SP value of 7 to 10 and a photopolymerization initiator with an extruder, a kneader or the like.

○ Method for forming coating layer of resin for surface modification (i) Method for forming coating layer of solvent-type surface-modified resin After coating on an olefin resin, it can be laminated by drying. Examples of the application method include, but are not limited to, a method in which a proper amount is impregnated into a brush, a nonwoven fabric, and the like, a roll coat, a spray coat, and a dip. For drying, either natural drying or forced heating drying with hot air can be applied. However, when the outside air temperature is low, both the wettability decreases due to the temperature decrease of the base material and the solution type primer, or the base depends on the type of solvent. A decrease in wettability to the material or a decrease in wettability due to a decrease in the pressing force of application may occur.

  If wetting in the solution state is not sufficiently achieved in this way, the surface modifying resin that has failed to wet will be present on the olefin base material, but the surface modifying resin must be heated. Therefore, the wettability between the surface modifying resin and the substrate can be improved.

  Therefore, it is preferable to heat dry at a softening point or higher than the melting point of the polymer having an SP value of 7 to 10 or higher and 150 ° C. or lower than natural drying, more preferably 60 ° C. to 180 ° C. It is desirable to obtain a stable adhesiveness that is not subject to When the drying temperature exceeds 180 ° C., the adherend is thermally deformed and deteriorates, which is not preferable. Further, the drying time cannot be limited here because it depends on the shape of the adherend and the characteristics of the dryer.

(Ii) Method for forming a coating layer of a solid surface-modified resin Using an extruder, an olefin-based resin and a surface-modifying resin are multi-layer extruded to form a coating layer of the surface-modifying resin on the surface of the olefin-based resin. Form.

Light irradiation The light irradiation in the present invention is performed on a coating layer of a surface modifying resin composed of a polymer having a SP value of 7 to 10 and a photopolymerization initiator, and adhesion of a base material composed of an olefin resin. It has the effect of further improving the properties. This is because hydrogen or chlorine is desorbed from the primer coating layer by light irradiation to generate radicals, and oxygen atoms in the air are bonded to the radical atoms to generate oxygen-containing groups. Energy is increased, and adhesion between the primer layer and the adhesive layer is improved. In addition, radical generation and formation of oxygen-containing groups by hydrogen abstraction proceed from a substrate made of an olefin resin by light irradiation, and surface energy is improved.

Examples of the light source used in the present invention include a low-pressure mercury lamp, a high-pressure mercury lamp, a xenon lamp, and a metal halide lamp. Moreover, preferable electromagnetic waves for the surface treatment are 180 to 500 nm of ultraviolet rays and visible light. Amount of light irradiation to the surface modifying resin laminated to the olefin resin is usually 100 mJ / cm ² or more, particularly preferably in the 200~10000mJ / cm ^2.

  In addition, in order to shorten processing time, the said drying process and the said light irradiation process can also be performed in parallel.

O Moisture curable reactive hot melt adhesive 1) Composition of adhesive The adhesive in the present invention is a moisture curable reactive hot melt adhesive mainly composed of an isocyanate group-containing urethane prepolymer.

  The isocyanate group-containing urethane prepolymer is obtained by reacting one or more polyols having two or more hydroxyl groups in the molecule with one or more polyisocyanates having two or more isocyanate groups in the molecule. It is a urethane prepolymer. The preferred weight average molecular weight of the urethane prepolymer is 1000 to 50000. 1 type (s) or 2 or more types can be used as the said urethane prepolymer.

1-2) Polyol The polyol which is a raw material of the urethane prepolymer has 2 or more, preferably 5 or less hydroxyl groups in the molecule, and conventionally known polyols can be used. Preferred specific examples are shown below.

(I) Polyester polyol The polyester polyol is obtained by random copolycondensation polymerization of one or more polycarboxylic acids and one or more polyols.

  Preferred polycarboxylic acids are those having 2 or more carboxyl groups in the molecule and 4 to 24 carbon atoms. Preferred specific examples include succinic acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, dodecanedioic acid, eicosanedioic acid, ε-caprolactone, terephthalic acid, isophthalic acid, phthalic anhydride, 2,6-naphthalenedicarboxylic Acids, trimellitic acid, paraoxybenzoic acid and the like.

  A preferred polyol has two or more hydroxyl groups in the molecule and a weight average molecular weight of 60 to 10,000. Preferred specific examples include ethylene glycol, propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, diethylene glycol, neopentyl glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, 1, Examples include 4-cyclohexanedimethanol, trimethylolpropane, pentaerythritol, 1,2,6-hexanetriol.

(Ii) Polyether polyol The polyether polyol has one or more ether bonds in the molecule, and preferred polyether polyols have a weight average molecular weight of 200 to 10,000. Preferred examples include polyethylene glycol, polypropylene glycol, polytetramethylene glycol and the like.

(Iii) Polyolefin polyol The polyolefin polyol has a polyolefin skeleton in the molecule, and a preferred polyolefin polyol has a weight average molecular weight of 200 to 10,000. Preferable specific examples include hydrogenated polyalkylene polyols such as hydrogenated polybutadiene polyol and hydrogenated polyisoprene polyol, and α-olefin copolymers.

(Iv) Other polyols There are polyalkylene polyols such as polybutadiene polyol and polyisoprene polyol, and polycarbonate polyol.

1-3) Polyisocyanate The polyisocyanate which is a raw material of the urethane prepolymer has two or more isocyanate groups in the molecule, and conventionally known ones can be used. Specifically, p-phenylene diisocyanate, 4,4′-diphenylmethane diisocyanate, tolylene diisocyanate, 4,4′-diphenylene diisocyanate, 1,5-octylene diisocyanate, trimethylene diisocyanate, tetramethylene diisocyanate, hexa Methylene diisocyanate, pentamethylene diisocyanate, 1,3-cyclopentane diisocyanate, 1,4-cyclohexane diisocyanate, 4,4'-methylenebis (cyclohexyl isocyanate), methyl 2,4-cyclohexane diisocyanate, methyl 2,6-cyclohexane diisocyanate, diphenylmethane Diisocyanate, 1,4-bis (isocyanate methyl) cyclohexane, 1,3-bis (isocyanate methyl) Hexane, and the like isophorone diisocyanate and carbodiimide-modified 4,4'-diphenylmethane diisocyanate.

  The preferred ratio of the amount of polyisocyanate charged to the polyol when producing the urethane prepolymer in the present invention is 1 to 5 in an equivalent ratio of isocyanate group / hydroxyl group, more preferably 1.2 to 3.

  In addition, in order to increase the moisture reactivity of the adhesive of the present invention, a tertiary amine-based or tin-based catalyst, in addition, a tackifier, a silane coupling agent, a filler, a plasticizer, a wax, a stabilizer, an oxidation An inhibitor or the like can be added as necessary.

2) Adhesive melting point Since the adhesive in the present invention is composed of a urethane prepolymer having a melting point, it becomes a crystalline solid at a temperature below the melting point, so when changing from a molten state to a solid, the viscosity of the resin with the melting point as a boundary. Has a characteristic of rapidly increasing. Therefore, electrostatic flocking work is performed when the adhesive layer applied to the substrate is in a molten state, and then the adhesive is crystallized by cooling and solidifying the adhesive, so that the olefin resin and the other adherend are bonded. A certain pile is firmly fixed to the adhesive layer, and the initial adhesive strength can be easily obtained.

  Specifically, by setting the melting point of the adhesive to 40 ° C. or higher, it is solid in a normal state, and the initial adhesive strength can be obtained by the cohesive force at the time of crystallization. When the melting point is less than 40 ° C., the initial adhesive strength in the normal state cannot be obtained. On the other hand, when the melting point of the adhesive is higher than 150 ° C., harmful substances may be generated when the adhesive is heated and melted, which is not desirable.

  The melting point of the adhesive can be measured by observing the presence or absence of melting with a microscope while heating from room temperature at 1 ° C./min.

3) Melt Viscosity of Adhesive The preferable melt viscosity of the adhesive in the present invention is 200 to 100,000 mPa · s in a 120 ° C. molten state, more preferable melt viscosity is 1000 to 50000 mPa · s, and still more preferable melt viscosity is 1000 to The most preferred viscosity is 1000 to 10,000 mPa · s. The melt viscosity can be easily measured with a BM viscometer.

4) Glass transition temperature of adhesive The preferable glass transition temperature of the adhesive in this invention is -50-60 degreeC, More preferably, it is -40-30 degreeC. By adjusting the glass transition temperature to the above preferred range, an adhesive having excellent adhesion to the substrate can be obtained.

5) Adhesive application method Any method known as a hot melt adhesive application method can be employed. A preferable coating temperature is 80 to 140 ° C, and a more preferable temperature is 80 to 120 ° C.

6) Electrostatic flocking method The flocking pile used is preferably about 3 denier. The pile length is preferably about 0.5 to 0.8 mm. In the flocking process, for example, a known down method type electrostatic flocking method or the like can be used. The humidity in the flocking tank is preferably 50 to 70%. The high-voltage electrode and the ground electrode in the electrostatic flocking machine are positioned at a certain interval, and a voltage is applied between both electrodes to generate an electric field. In this electric field, for example, a weather strip which is a hair transplant material subjected to primer treatment and hot melt treatment, a pile charged from a pile hopper is caused to fly into the electric field, and the uncured hot melt adhesive layer is flocked. Pile can be thrown. The distance between the high-voltage electrode and the ground electrode is preferably 100 to 150 mm, and the applied voltage can be about 25000 to 30000V.

7) Cooling and solidifying method of adhesive When electrostatic flocking is performed using a hot melt adhesive, it is gaseous and liquid for the purpose of quenching and solidifying the unsolidified adhesive layer on which the pile has been flocked in a short time. The refrigerant may be used. Examples of the refrigerant include water, a mixture of water and ethylene glycol, and other organic solvents, with VOC and safe water being particularly preferable. Although there is no restriction | limiting in particular in the temperature of a refrigerant | coolant, it needs to be lower than melting | fusing point of the adhesive agent used for flocking of a pile, and 25 degrees C or less is preferable normally. Moreover, although there is no restriction | limiting in particular in the cooling time with a refrigerant | coolant, Since the length of a manufacturing line can be shortened, so that it is short time, it is preferable normally within 1 minute.

  Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples. In addition, the performance evaluation in each Example and the comparative example followed the following method.

Preparation of surface modifying resin The composition was prepared according to Table 1.

○ Abrasion test Abrasion test includes weather strip immediately after adhesion curing, heat aging test (80 ° C., 240 hours), weather resistance test (exposure to sunshine weather meter for 200 hours), water resistance test (immersion in water for 24 hours), And a weather strip after being subjected to a window washer resistance test (immersed in a window washer solution diluted to 1/3 for 24 hours) with a load of 8.33 N / 100 mm applied to the electrostatic flocking site. Ten thousand wear tests were conducted, the flocked state was confirmed, and the case where there was no peeling was regarded as acceptable, and the case where it was separated was regarded as unacceptable.

○ VOC test As a VOC test for weather strips at the extrusion molding stage and weather strips subjected to electrostatic flocking, the contents of toluene, xylene and ethylbenzene were measured using GC / MS (ATD = QP2010) manufactured by Shimadzu Corporation. .

[Materials used for evaluation]
Olefin-based resin: Olefin-based thermoplastic elastomer (trade name Miralastomer manufactured by Mitsui Chemicals, Inc.)
Hot-melt adhesive: A moisture-curable reactive hot-melt adhesive mainly composed of an isocyanate group-containing urethane prepolymer (trade name Aronmelt R RHT-310, manufactured by Toagosei Co., Ltd.). The melting point is 53 ° C., and the melt viscosity is 3,000 mPa · s in a 120 ° C. molten state.

Light irradiation The light irradiation device used was a high-pressure mercury lamp manufactured by Ushio Electric Co., Ltd. with an output of 3.2 kW, and the irradiation energy was 2000 mJ / cm ² as measured by an integrating photometer with a wavelength of 365 nm.

[Example 1]
The surface modification resin composition 1 was applied to the flocked surface of a weather strip produced by extrusion molding of an olefin-based resin, dried with hot air and laminated with the surface modifying resin on the flocked surface, and then irradiated with light. A hot melt adhesive melted at 120 ° C. was applied thereon, electrostatic flocking was applied, and the adhesive was cured at room temperature for one week.

  The abrasion test includes a weather strip immediately after adhesion curing, a heat aging test (80 ° C., 240 hours), a weather resistance test (exposure to a sunshine weather meter for 200 hours), a water resistance test (immersion in water for 24 hours), and a wind resistance test. The weather strip after the washer test (immersed in window washer solution diluted to 1/3 for 24 hours) was repeated 10,000 times with a load of 8.33 N / 100 mm applied to the electrostatic flocking site. A wear test was performed.

[Example 2]
A wear test was conducted under the same conditions as in Example 1 except that the resin composition 2 for surface modification was used.

[Example 3]
A wear test was conducted under the same conditions as in Example 1 except that the resin composition 3 for surface modification was used.

[Example 4]
The VOC of the weather strip produced in Example 1 was measured.

[Comparative Example 1]
A wear test was performed under the same conditions as in Example 1 except that Davybond (trade name, manufactured by Diabond Industry Co., Ltd., chlorine content: about 2.5 to 10 wt%) was applied as a solvent-type primer containing chlorinated PP as a main component. went.

[Comparative Example 2]
A wear test was performed under the same conditions as in Example 1 without applying the primer.

[Comparative Example 3]
The surface of the hairstrip of the weather strip produced by extrusion molding of an olefin resin was not treated with a primer, but instead was subjected to a surface treatment by plasma irradiation with a plasma irradiation device under an irradiation distance of 6 mm and an irradiation time of 3 seconds. A wear test was performed under the same conditions as in Example 1 except for the above. As the plasma irradiation apparatus, ST-7000 manufactured by Keyence Corporation was used.

[Comparative Example 4]
A surface treatment by corona discharge was carried out by using a corona discharge device with an irradiation distance of 5 mm and an irradiation time of 15 seconds without applying a primer treatment on the surface of the weatherstrip produced by extrusion molding of an olefin resin. A wear test was performed under the same conditions as in Example 1 except for the above. The corona discharge device used was Polydyne manufactured by Navista.

[Comparative Example 5]
The VOC of the weather strip prepared under the same conditions as in Comparative Example 1 was measured except that olestar (trade name, manufactured by Mitsui Takeda Chemical Co., Ltd.) was used as the adhesive.

  Tables 2 and 3 summarize the evaluation regarding the flocking adhesiveness, and Table 4 summarizes the VOC (volatile organic compound generation amount).

  As shown in Tables 2 and 3, the results of various abrasion tests for evaluating flocking adhesion showed no substantial peeling in each Example, whereas in Comparative Examples, there were many peelings except for Comparative Example 1. The flocking adhesion was unacceptable. In Comparative Example 1, a solvent-based adhesive is used, and the working environment is not good.

  From the results of Table 4 for VOC (amount of volatile organic compounds generated), in Comparative Example 5, a significant amount of volatile solvent such as toluene was detected in comparison with Example 4 and reference (without adhesive and primer). Met.

Super Clone: Product name manufactured by Nippon Paper Industries Co., Ltd.
Auroren: trade name of Nippon Paper Industries Co., Ltd.
* 1) Chlorine content of about 25 wt%, softening point 70-80 ° C., SP value 8.7 (hereinafter, the meaning of * 1 is the same)
* 2) Chlorine content of about 20 wt%, softening point 75-80 ° C, SP value 8.4 (hereinafter, the meaning of * 2 is the same)
* 3) Maleic anhydride modification, melting point 60-70 ° C., SP value 8.0 (hereinafter, the meaning of * 3 is the same)

Minimal: Level at which significant detection is not possible

  The present invention provides a method of strongly electrostatically flocking a base material made of an olefin resin with a solvent-free, moisture-curable reactive hot melt adhesive.

  Therefore, according to the present invention, it becomes easy to replace an automobile flocking product whose base material in the automobile industry is made of a vinyl chloride resin with an olefin resin, and the weight reduction of the member and the reduction of the environmental load are promoted.

Specifically, it is possible to produce an automobile flocking product at low cost by using a low activity resin such as a polyolefin elastomer (TPO) in which a rubber component such as an EPDM component or the like is added to polypropylene or polyethylene and a resin thereof.

Claims (3)

  A surface modification resin coating layer composed of a polymer having a SP value of 7 to 10 and a photopolymerization initiator is formed on a base material made of an olefin resin, and after irradiating light on the coating layer, A moisture curable reactive hot melt adhesive having an isocyanate group-containing urethane prepolymer as a main component and a melting point of 40 ° C. or higher and 150 ° C. or lower is applied, and a pile is electrostatically flocked on the adhesive layer formed thereby. A method for producing an automobile flocking product based on an olefin resin.   A method for producing a flocking product for automobiles, wherein the polymer having an SP value of 7 to 10 according to claim 1 is a chlorinated polyolefin. A method for producing a flocking product for automobiles, wherein the polymer having an SP value of 7 to 10 according to claim 1 is an acid-modified polyolefin.