JP2011140644A - Urethane resin particles for slush molding - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide resin particles that are free of defects associated with sliding-down or agglomeration of a pigment when pigmented on the surface of the resin particles. <P>SOLUTION: The urethane resin particles for slush molding (C) is urethane resin particles that contains a urethane resin (D) and an additive (N) and have a shape factor SF1 of 101-200, a shape factor SF2 of 120-240, and a median particle diameter of 20-500 μm. The urethane resin (D) contained in (C) has a urea group concentration of 0.5-10 wt.%, a total concentration of a urethane group and the urea group of 4-20 wt.%, a melting point of 160-260°C, and a glass transition temperature of -65 to 0°C. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present invention relates to a urethane resin particle for slush molding whose surface is uneven.

In recent years, the slush molding method can easily form products with complex shapes (undercut, deep drawing, etc.), can be made uniform in thickness, and has a good material yield rate. Conventionally, vinyl chloride resin powder slush molded products have often been used as skin materials for automotive interior parts such as instrument panels and door trims.
However, when the vinyl chloride material is used for a long period of time depending on the usage environment, the plasticizer contained therein moves to the surface and the soft feeling is impaired. Further, when incineration is performed after scrapped vehicles, hydrogen chloride gas is generated depending on the incineration temperature, and the incinerator may be corroded.

In order to solve these problems, a powder slush molding material made of a thermoplastic resin other than vinyl chloride has been developed. For example, a thermoplastic polyurethane elastomer having a number average molecular weight of 20,000 to 50,000 and a glass transition temperature of −35 ° C. or lower is used (Patent Document 1). Moreover, the particulate polyurethane resin composition which has as a main component the thermoplastic urethane resin synthesize | combined in the non-aqueous dispersion medium, the vinyl monomer polymer, and a heat crosslinkable monomer is used (patent document 2). In addition, a thermoplastic elastomer composition powder having a particle diameter of 1 to 1000 μm, which is composed of an acrylic block copolymer and an acrylic polymer having at least 1.1 reactive functional groups in one molecule is used ( Patent Document 3).

Slush molding materials that are colored to give a high-class feel as the skin material for automotive interior parts are used, but slush molding materials made of these thermoplastic resins also contain uncolored particles. After the synthesis, coloring is performed by coating the surface with a colorant such as an inorganic pigment or an organic pigment. However, in the case of this coloring method, the pigment particles adhering to the surface of the resin particles slide off from the surface due to the shear at the time of mixing and stirring in the coloring step or the subsequent step, and the pigment particles aggregate on the particle surface. There is a problem that the color of the color does not appear, and a lump of pigment is mixed in the product.

In order to solve such a problem, a method has been proposed in which a colorant is mixed in a liquid prepolymer stage before the resin is made into particles, and then is made into particles. (Patent Document 4).

Japanese Patent Laid-Open No. 11-49948 JP 2009-91519 A JP 2009-67853 A No. 2005/0997901

However, after mixing the colorant at the liquid prepolymer stage before the resin is made into particles, in the method of making particles, since the pigment particles are taken into the resin particles, the pigment slides down from the resin particles. However, the pigments do not aggregate on the particle surface, but the production equipment must be carefully cleaned for each color change of the product compared to the method of coloring the particle surface described above. bad.
An object of the present invention is to provide urethane resin particles for slush molding that can eliminate defects due to pigment slipping and aggregation, and that is highly productive, while being colored on the surface of the resin particles.

As a result of intensive studies to obtain the resin particles as described above, the present inventors formed fine irregularities on the surface of the particles, and added a colorant to the surface irregularities, thereby forming a depression on the surface. Since the pigment particles can be fixed, the present inventors have found that the particles can be colored without causing the pigments to slide down and aggregate.

That is, this invention is a urethane resin particle containing urethane resin (D) and an additive (N), Comprising: The shape factor SF1 of this urethane resin particle is 101-200, and shape factor SF2 is 120-240. Urethane resin particles for slush molding (C) having a central particle size of 20 to 500 μm; a method for coloring the urethane resin particles (C); a urethane resin molded product obtained by slush molding the urethane resin particles (C) It is.

  By using the urethane resin particles (C) for slush molding of the present invention, it is possible to eliminate problems due to pigment sliding and aggregation while being colored on the surface of the resin particles.

The slush molding urethane resin particles (C) of the present invention have a shape factor SF1 of 101 to 200 and a shape factor SF2 of 120 to 240.
Since the surface of the urethane resin particles (C) is uneven, SF1 is 101 or more. Particles having a shape factor SF1 exceeding 200 become irregular in shape and powder flowability deteriorates.
When the shape factor SF2 is less than 120, even when a colorant is added to the particles and the pigment particles are fixed on the surface, the pigment particles on the surface slide down and aggregate the pigment particles due to shear during stirring in the subsequent step. As a result, the original color does not develop. Moreover, when the aggregate of pigment particles becomes large, it becomes a foreign substance, and the quality of the product is deteriorated. On the other hand, particles having an SF2 of over 240 have surface irregularities that make it difficult for the pigment to enter the gaps between the irregularities, resulting in poor pigment dispersion stability.

The shape factor SF1 indicates the roundness of the shape of the particle, and the square of the longest diameter of the figure formed by projecting urethane particles onto a two-dimensional plane represented by the following formula (1) is divided by the figure area AREA. And multiplied by 100π / 4.
SF1 = {(longest diameter) ² / (AREA)} × (100π / 4) (1)
When the value of SF1 is 100, the shape of the urethane particles is a true sphere, and the larger the value of SF1, the more irregular the particles.
The shape factor SF2 indicates the ratio of irregularities in the shape of the particle, and the square of the perimeter PERI of the figure formed by projecting urethane particles onto the two-dimensional plane represented by the following formula (2) is represented by the area AREA. Divided by 100 / 4π.
SF2 = {(PERI) ² / (AREA)} × (100 / 4π) (2)
When the value of SF2 is 100, unevenness does not exist on the urethane particle surface, and as the SF2 value increases, the unevenness of the urethane particle surface becomes more prominent.
The shape factors SF1 and SF2 are measured by taking a picture of urethane particles with a scanning electron microscope (for example, S-800: manufactured by Hitachi, Ltd.), a microscope (USB digital scale: manufactured by SCARA Co., Ltd.), etc. Examples thereof include a method of analyzing by introducing into an apparatus (for example, LUSEX3: manufactured by Nireco), and a method of measuring using a flow type particle image analyzer (for example, FPIA-3000: manufactured by Sysmex).

The urethane resin particles (C) have a center particle size of 20 to 500 μm, preferably 30 to 400 μm, and more preferably 50 to 300 μm.
When the center particle diameter of (C) is less than 20 μm, the powder fluidity is deteriorated, so that the formability at the time of slush molding is deteriorated and dust is easily generated, which leads to deterioration of the working environment. . When the center particle diameter of (C) exceeds 500 μm, a powder shape that cannot be leveled after slush molding remains, or many pinholes are generated on the mold surface.
Here, the central particle diameter is a volume average particle diameter, which is a value of a particle diameter of 50% under a sieve measured by a laser light scattering method. Examples of the measuring instrument include Microtrac HRA particle size analyzer 9320-X100 (manufactured by Nikkiso Co., Ltd.).

The slush molding urethane resin particles (C) of the present invention contain a urethane resin (D) and an additive (N) as essential components. Additive (N) is an additive (N1) that is added before the step of granulating the urethane resin (D), and an additive that is added after the urethane resin (D) is granulated into urethane resin particles (P). There is an agent (N2), and the additive (N) is used as the additive (N1) or additive (N2). Examples of the additive (N1) include inorganic fillers, pigment particles (E), plasticizers, mold release agents, organic fillers, stabilizers, and dispersants. Examples of the additive (N2) include pigments and plasticizers. , Mold release agents, organic fillers, antiblocking agents, stabilizers and dispersants.
As for the addition amount (weight%) of an additive (N), 0.01-50 are preferable with respect to the weight of (D), More preferably, it is 1-30.

Inorganic fillers are kaolin, talc, silica, titanium oxide, calcium carbonate, bentonite, mica, sericite, glass flake, glass fiber, graphite, magnesium hydroxide, aluminum hydroxide, antimony trioxide, barium sulfate, zinc borate , Alumina, magnesia, wollastonite, zonotlite, whisker, metal powder and the like. Of these, kaolin, talc, silica, titanium oxide and calcium carbonate are preferable from the viewpoint of promoting crystallization of the thermoplastic resin, and kaolin and talc are more preferable.
The volume average particle diameter (μm) of the inorganic filler is preferably from 0.1 to 30, more preferably from 1 to 20, particularly preferably from 5 to 10, from the viewpoint of dispersibility in the thermoplastic resin.

It does not specifically limit as pigment particle (E), A well-known organic pigment and / or an inorganic pigment can be used, (C) 10 weight part or less normally per 100 weight part, Preferably it is 0.01-5 weight Partly formulated. Examples of the organic pigment include insoluble or soluble azo pigments, copper phthalocyanine pigments, quinacridone pigments, and inorganic pigments include chromate, ferrocyan compounds, metal oxides (titanium oxide, iron oxide, Zinc oxide, aluminum oxide, etc.), metal salts [sulfates (barium sulfate, etc.), silicates (calcium silicate, magnesium silicate, etc.), carbonates (calcium carbonate, magnesium carbonate, etc.), phosphates (calcium phosphate, magnesium phosphate, etc.) Etc.], metal powder (aluminum powder, iron powder, nickel powder, copper powder, etc.), carbon black, and the like. Although there is no limitation in particular about the average particle diameter of pigment particle (E), it is 0.05-5.0 micrometers normally, Preferably it is 0.2-1 micrometer.

Examples of plasticizers include phthalate esters (dibutyl phthalate, dioctyl phthalate, dibutylbenzyl phthalate, diisodecyl phthalate, etc.); aliphatic dibasic acid esters (di-2-ethylhexyl adipate, 2-ethylhexyl sebacate, etc.) ); Trimellitic acid ester (trimellitic acid tri-2-ethylhexyl, trimellitic acid trioctyl, etc.); fatty acid ester (butyl oleate, etc.); benzoic acid esters [polyethylene glycol (degree of polymerization 2-10) dibenzoic acid Ester, polypropylene glycol (degree of polymerization 2-10), etc.]; aliphatic phosphate ester (trimethyl phosphate, triethyl phosphate, tributyl phosphate, tri-2-ethylhexyl phosphate and tributoxy phosphate) Aromatic phosphates (triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, cresyl diphenyl phosphate, xylenyl diphenyl phosphate, 2-ethylhexyl diphenyl phosphate and tris (2,6-dimethylphenyl) phosphate, etc.) A halogen aliphatic phosphate ester (such as tris (chloroethyl) phosphate, tris (β-chloropropyl) phosphate, tris (dichloropropyl) phosphate and tris (tribromoneopentyl) phosphate); and a mixture of two or more of these Can be mentioned.

As the mold release agent, known mold release agents can be used, and fluorine compound type mold release agents (triperfluoroalkyl phosphate (8 to 20 carbon atoms) ester such as triperfluorooctyl phosphate and triperfluorododecyl phosphate). Etc.); silicone compound mold release agents (dimethylpolysiloxane, amino-modified dimethylpolysiloxane, carboxyl-modified dimethylpolysiloxane, etc.), fatty acid ester mold release agents (mono- or polyhydric alcohol esters of fatty acids having 10 to 24 carbon atoms, For example, butyl stearate, hydrogenated castor oil, ethylene glycol monostearate, etc.); aliphatic acid amide type mold release agents (mono- or bisamides of fatty acids having 8 to 24 carbon atoms such as oleic acid amide, palmitic acid amide, stearic acid Of amide and ethylenediamine Metal soap (such as magnesium stearate and zinc stearate); natural or synthetic wax (such as paraffin wax, microcrystalline wax, polyethylene wax and polypropylene wax); and mixtures of two or more thereof Is mentioned.

It does not specifically limit as an antiblocking agent, A well-known inorganic type antiblocking agent, an organic type antiblocking agent, etc. can be used. Examples of the inorganic blocking inhibitor include silica, talc, titanium oxide and calcium carbonate. Organic blocking inhibitors include thermosetting resins with a particle size of 10 μm or less (thermosetting polyurethane resins, guanamine resins, epoxy resins, etc.) and thermoplastic resins with a particle size of 10 μm or less (thermoplastic polyurethane urea resin and poly ( (Meth) acrylate resin, etc.).

A stabilizer is a carbon-carbon double bond (such as an ethylene bond which may have a substituent) in the molecule (excluding a double bond in an aromatic ring), a carbon-carbon triple bond (with a substituent). A compound having an acetylene bond which may be present can be used, and an ester (ethylene glycol di (meth) acrylate) of (meth) acrylic acid and a polyhydric alcohol (2 to 10 valent polyhydric alcohol, the same shall apply hereinafter). , Trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate and dipentaerythritol tri (meth) acrylate); esters of (meth) allyl alcohol and divalent to hexavalent polycarboxylic acids (diallyl phthalate) And trimellitic acid triallyl ester); poly (meth) allyl ether of polyhydric alcohol (pentaerythritol) Poly (meth) allyl ether, etc.); polyhydric alcohol polyvinyl ether (ethylene glycol divinyl ether, etc.); polyhydric alcohol polypropenyl ether (ethylene glycol dipropenyl ether, etc.); polyvinyl benzene (divinyl benzene, etc.) and their 2 A mixture of seeds or more may be mentioned. Among these, from the viewpoint of stability (radical polymerization rate), an ester of (meth) acrylic acid and a polyhydric alcohol is preferable, and trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate and more preferably Dipentaerythritol penta (meth) acrylate.

As a mixing device used when the additive (N2) is added to and mixed with the urethane resin particles (P), a known powder mixing device can be used, a container rotating mixer, a fixed container mixer, and a fluid motion. A type mixer can be used. Among these mixing devices, a fixed container type mixer is preferable, and a high-speed flow type mixer, a double-shaft paddle type mixer, a high-speed shear mixing device (Hensiel mixer (registered trademark), etc.), a low-speed mixing device ( Planetary mixers, etc.) and conical screw mixers (Nauta mixer (registered trademark), etc.), more preferably double-shaft paddle type mixers, low speed mixing devices (planetary mixers, etc.) and conical screw mixers (Nauta mixer (registered trademark)) , The following is omitted)). The mixing is preferably dry blended.

The slush molding urethane resin particles (C) of the present invention are preferably granulated particles. Examples of the method for producing the urethane resin particles (C) include the following methods.

There is a method of obtaining the urethane resin particles (C) of the present invention by synthesizing the primary particles (p1) containing the urethane resin (D) as a main component, drying them as necessary, and then granulating them.

In this case, the primary particles (p1) have a particle size of 0.3 to 50 μm, preferably 1 to 30 μm, and more preferably 3 to 10 μm. Moreover, as a method of granulating, primary particles (p1) are heat-fused on the surface and granulated, a binder component is added to the primary particles (p1), and primary particles (p1) are added by a binder. The method of bonding and granulating each other is mentioned.

As a manufacturing method of primary particles (p1),
(I) An organic solvent solution of urethane resin (D) or a precursor (d0) of urethane resin (D) or an organic solvent solution thereof, a dispersion stabilizer, an aqueous dispersion containing a surfactant, or a dispersion stabilizer In the case of the precursor (d0) after being dispersed in an organic solvent in which the urethane resin (D) or its precursor (d0) is not dissolved, the polymer is polymerized, and then this is solid-liquid separated and dried. How to get.
(Ii) A method of obtaining a lump or pellet resin of urethane resin (D) and then powdering it.
When the precursor (d0) is used, it becomes a urethane resin (D) after primary particle formation. The particleizer is not particularly limited as long as it is generally commercially available as an emulsifier or a disperser. For example, a homogenizer (manufactured by IKA), polytron (manufactured by Kinematica), TK auto homomixer (manufactured by Primics) ) Etc. batch type emulsifier, Ebara milder (manufactured by Ebara Seisakusho), TK fill mix, TK pipeline homomixer (manufactured by Primics), colloid mill (manufactured by Shinko Pantech), thrasher, trigonal wet pulverizer (Mitsui Miike Kako Co., Ltd.), Capitolon (Eurotech Co., Ltd.), fine flow mill (Pacific Kiko Co., Ltd.), etc. High-pressure emulsifier such as APV Gaurin (manufactured by Gaurin), membrane milk such as membrane emulsifier (manufactured by Chilling Industries) Machine, Vibro Mixer (Hiyaka Kogyo) vibrating emulsifier such as, ultrasonic emulsifier such as an ultrasonic homogenizer (manufactured by Branson Co., Ltd.). Among these, preferred from the viewpoint of particle size distribution are APV Gaurin, homogenizer, TK auto homomixer, Ebara milder, TK fill mix, and TK pipeline homomixer.

As a solid-liquid separation method, a known centrifugal separation, belt press, filter press, or the like can be applied.
Furthermore, primary particles (p1) can be obtained by drying by a known method.
A known granulator can be used as a granulator used when the obtained primary particles (p1) are made into urethane resin particles (P) by granulation. For example, there are a kneader, a paddle mixer, a rotary drum type mixer, a ribbon dryer, and a disk dryer. Henschel Mixer (Mitsui Miike Chemical), Nauta Mixer (Hosokawa Micron), TURBO SPHERE Mixer (Sumitomo Heavy Industries), Ribbon Blender (Hosokawa Micron), Turbulizer (Hosokawa Micron), Solid Air (Hosokawa Micron) ) And the like. As temperature in the granulation tank in the case of implementing the manufacturing method which concerns on this invention, 0-200 degreeC, Preferably 70-150 degreeC is preferable.

The method for producing the bulk or pellet urethane resin (D) can be obtained, for example, by a batch type kneader such as a kneader or a screw type extruder equipped with a side feeder. The lump or pellet thermoplastic polyurethane is cooled by liquid nitrogen and pulverized using an impact type pulverizer such as a turbo mill, pin mill, hammer mill, etc., to obtain primary particles (p1).

Using the above granulator, granulation by heat fusion of the primary particle (p1) surface, adhesion granulation by adding a binder, and swelling and fusion of the primary particle (p1) surface by an organic solvent. There is a granulation method. Examples of the binder used in this case include the plasticizers mentioned in the description of the additive. Moreover, as an organic solvent, the well-known thing with affinity with a urethane resin (D) is mentioned.

As another method, an organic solvent solution of the urethane resin (D) or a precursor (d0) of the urethane resin (D) or an organic solvent solution thereof is used as an aqueous dispersion containing a dispersion stabilizer, a surfactant, or dispersion stability. After granulating into primary particles (p2) in an organic solvent that does not dissolve the urethane resin (D) or its precursor (d0) containing the agent, the particles (p2) are aggregated in the dispersion and granulated. To obtain a dispersion slurry of urethane resin particles (C). In this case, the primary particles have a particle size of 0.3 to 50 μm, preferably 1 to 30 μm, more preferably 3 to 10 μm. It is. As a method of agglomerating particles, an organic solvent, salt, acid, base, or the like that lowers the dispersion stability of the primary particles (p2) is added to the aqueous dispersion in advance. Examples thereof include a method of adding an organic solvent, salt, acid or base, a method of using a dispersant having low dispersion stability, and a method of reducing the concentration of the dispersant. When the precursor (d0) is used, it becomes urethane resin (D) after granulation. In this case, as the particleizing apparatus, the same one as described above can be used, and the solid-liquid separation and drying steps can also be performed by the same method as described above.

Among these methods, a method is preferred in which the primary particles that can be formed in three steps of granulation, solid-liquid separation, and drying of the urethane resin particles (C) are granulated in a dispersion. The formation of the concavo-convex shape by granulation exemplified above is a build-up type process in which the concavo-convex shape is formed by a combination of particles smaller than the final particle size. In addition to this, the method for forming irregularities also includes a method for forming irregularities by physically scraping or chemically treating particles on a smooth surface. It is disadvantageous in that it is necessary to remove the abrasive after shaving and the debris of the shaved particles, and that chemical treatment requires post-treatment of the chemical solution. Also, from the viewpoint of resources, a part to be scraped off and a part to be dissolved by chemical treatment are generated, so that the process is wasteful. Therefore, it can be said that a method of forming irregularities on the particle surface by granulation of primary particles is preferable.

The urethane resin (D) constituting the urethane resin particles (C) of the present invention has a urea group concentration of 0.5 to 10% by weight and a total of the urethane group concentration and the urea group concentration of 4 to 20% by weight. It is preferable that the melting point is 160 to 260 ° C and the glass transition temperature is -65 to 0 ° C.
Since the urea group remarkably improves the strength, solvent resistance, and wear resistance of the urethane resin (D), when the urea group is contained, the performance of the urethane resin particles (C) can be greatly improved. When the urea group is in the range of 0.5 to 10% by weight, the effect of improving the strength, solvent resistance, and abrasion resistance due to the urea group is remarkable, and when the urethane resin particles (C) are molded, Since the melting point and melt viscosity can be kept low, the thermal energy required during molding can be reduced. The urea group concentration is preferably 0.5 to 10% by weight, more preferably 1.0 to 7.0% by weight, and most preferably 1.5 to 5.0% by weight.
At the same time, the urethane group is improving the performance of the urethane resin (D) in the same manner as the urea group, and the total of the urethane group concentration and the urea group concentration is preferably 4 to 20% by weight, more preferably 6 to 15% by weight. Preferably, 8 to 12% by weight is most preferable. The urethane group concentration and urea group concentration in the present invention are the weight percent concentrations of urethane groups and urea groups with respect to the urethane resin (D).

The melting point of the urethane resin (D) constituting the urethane resin particles (C) of the present invention is preferably 160 to 260 ° C, and more preferably 210 to 250 ° C. If melting | fusing point is 160-260 degreeC, it is excellent in the blocking property of particle | grains in a general preservation | save environment, and can reduce the thermal energy at the time of shaping | molding. The glass transition temperature of (D) is preferably −65 to 0 ° C., more preferably −50 to −10 ° C. If the glass transition temperature is −65 to 0 ° C., it can have impact resistance even at a lower temperature.

Examples of the urethane resin (D) in the present invention include aliphatic diisocyanate (a1), monool (a2), high molecular diol (a3) having a number average molecular weight of 500 to 10,000, and optionally low molecular diol (a4). And those obtained by reacting an alicyclic diamine and / or an aliphatic diamine (b) with the isocyanate group-terminated urethane prepolymer (a) derived from
As the aliphatic diisocyanate (a1) constituting the above (a), (i) an aliphatic diisocyanate having 2 to 18 carbon atoms (excluding carbon in the NCO group, the same shall apply hereinafter) [ethylene diisocyanate, tetramethylene diisocyanate, hexa Methylene diisocyanate (HDI), dodecamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, 2,6-diisocyanatomethyl caproate, bis (2-isocyanatoethyl) fumarate, bis (2-isocyanate) Natoethyl) carbonate, 2-isocyanatoethyl-2,6-diisocyanatohexanoate, etc.]; (ii) alicyclic diisocyanate having 4 to 15 carbon atoms [isophorone diisocyanate (IPDI), dicyclohexylmethane-4,4 '− Diisocyanate (hydrogenated MDI), cyclohexylene diisocyanate, methylcyclohexylene diisocyanate (hydrogenated TDI), bis (2-isocyanatoethyl) -4-cyclohexene, etc.]; (iii) an aromatic aliphatic group having 8 to 15 carbon atoms Diisocyanates [m- and / or p-xylylene diisocyanate (XDI), α, α, α ′, α′-tetramethylxylylene diisocyanate (TMXDI), etc.]; (iv) modified products of these diisocyanates (carbodiimide groups, A diisocyanate-modified product having a uretdione group, a uretoimine group, a urea group, etc.); and a mixture of two or more of these. Of these, preferred are aliphatic diisocyanates or alicyclic diisocyanates, and particularly preferred are HDI, IPDI, and hydrogenated MDI.

Examples of the monool (a2) include aliphatic monools having 1 to 8 carbon atoms [linear monool (methanol, ethanol, propanol, butanol, pentanol, hexanol, octanol, etc.), monool having a branched chain ( Isopropyl alcohol, neopentyl alcohol, 3-methyl-pentanol, 2-ethylhexanol, etc.]; monools having a cyclic group having 6 to 10 carbon atoms [alicyclic group-containing monools (cyclohexanol, etc.), aromatic rings Containing monools (such as benzyl alcohol)] and mixtures of two or more thereof. Of these, preferred are aliphatic monools. Examples of the polymer monool include polyester monool, polyether monool, polyether ester monool, and a mixture of two or more thereof.

Examples of the polymer diol (a3) having a number average molecular weight of 500 to 10,000 include polyester diol, polyether diol, polyether ester diol, and a mixture of two or more thereof. Examples of the polyester diol include (i) a low molecular diol and a dicarboxylic acid or an ester-forming derivative thereof [an acid anhydride, a lower alkyl (carbon number 1 to 4) ester, an acid halide, etc.] or a dialkyl carbonate (carbon number of an alkyl group). 1 to 4) by condensation polymerization; (ii) ring-opening polymerization of a lactone monomer using a low molecular diol as an initiator; (iii) a dicarboxylic acid anhydride and an alkylene oxide are reacted using a low molecular diol as an initiator. And mixtures of two or more thereof.

Specific examples of the low molecular diols (i), (ii) and (iii) above include aliphatic diols having 2 to 8 carbon atoms [linear diols (ethylene glycol, diethylene glycol, 1,3-propanediol, 1, 4-butanediol, 1,5-pentanediol, 1,6-hexanediol, etc.), branched diols (propylene glycol, neopentyl glycol, 3-methyl-1,5-pentanediol, 2,2-diethyl) -1,3-propanediol, 1,2-, 1,3- or 2,3-butanediol, etc.]]; diols having a cyclic group [an alicyclic group-containing diol having 6 to 15 carbon atoms [1, 4-bis (hydroxymethyl) cyclohexane, hydrogenated bisphenol A, etc.], aromatic ring-containing diol having 8 to 20 carbon atoms (m- or p- Silylene glycol, etc.), oxyalkylene ethers of bisphenols (bisphenol A, bisphenol S, bisphenol F, etc.), oxyalkylene ethers of polynuclear phenols (dihydroxynaphthalene, etc.), bis (2-hydroxyethyl) terephthalate, etc.]; Examples thereof include oxide adducts (molecular weight less than 500) and mixtures of two or more thereof. Of these, preferred are aliphatic diols and alicyclic group-containing diols.

As the alkylene oxide, ethylene oxide (EO), propylene oxide (PO), 1,2-, 1,3-, 1,4- or 2,3-butylene oxide, styrene oxide, carbon number 5-10 or More α-olefin oxide, epichlorohydrin and combinations of two or more of these (block or random addition) can be mentioned.

Specific examples of the dicarboxylic acid or the ester-forming derivative thereof (i) include, as specific examples of the dicarboxylic acid or the ester-forming derivative thereof, an aliphatic dicarboxylic acid having 4 to 15 carbon atoms [succinic acid, adipic acid, Sebacic acid, glutaric acid, azelaic acid, maleic acid, fumaric acid, etc.], aromatic dicarboxylic acids having 8 to 12 carbon atoms [terephthalic acid, isophthalic acid, etc.], and ester-forming derivatives thereof [acid anhydride (phthalic anhydride) , Maleic anhydride, etc.), lower alkyl esters (dimethyl ester, diethyl ester, etc.), acid halides (acid chloride, etc.) and the like, and mixtures of two or more thereof.

Examples of the lactone monomer (ii) include lactones having 4 to 12 carbon atoms, such as γ-butyrolactone, γ-valerolactone, ε-caprolactone, and mixtures of two or more thereof.

The polyether diol is a polyether diol obtained by dehydration reaction of two hydroxyl group-containing compounds (for example, the low molecular diol, divalent phenols, etc.), and a structure in which an alkylene oxide is added to the two hydroxyl group-containing compounds. The compound of this is mention | raise | lifted. Examples of the divalent phenols include bisphenols [bisphenol A, bisphenol F, bisphenol S, etc.], monocyclic phenols [catechol, hydroquinone, etc.], and the like.
Among these, preferred are polytetramethylene glycol and dihydric phenols to which alkylene oxide is added, and more preferred are those obtained by adding EO to dihydric phenols.

Further, as the polyether ester diol, the polyester diol in which the polyether diol is used instead of the low molecular diol of the raw material, for example, one or more of the polyether diol and the dicarboxylic acid exemplified as the raw material of the polyester diol Or what is obtained by polycondensation with 1 or more types of the ester-forming derivative is mentioned. Among these polymer diols (a3), preferred are polyester diols, and more preferred are polycondensates of low-molecular diols and dicarboxylic acids.

As the low molecular diol (a4) used together with the above (a2) and (a3) as needed, the low molecular diol exemplified as the starting material for the above-mentioned poester diol can be used. Preferred as (a4) is an aliphatic diol. The amount of (a4) used is usually 20% by weight or less, preferably 10% by weight or less, based on the weight of (a3).

The reaction temperature for producing the isocyanate group-terminated urethane prepolymer (a) may be the same as that usually employed for urethanization, and is usually 20 ° C to 100 ° C when a solvent is used. When not used, it is usually 20 ° C to 220 ° C, preferably 80 ° C to 200 ° C. In the prepolymerization reaction, a catalyst usually used for polyurethane can be used if necessary to accelerate the reaction. Examples of the catalyst include amine-based catalysts [triethylamine, N-ethylmorpholine, triethylenediamine, etc.], tin-based catalysts [trimethyltin laurate, dibutyltin dilaurate, dibutyltin malate, etc.]. When (a) is produced, by using (a1) so as to be an excess mole of isocyanate groups with respect to the total moles of terminal hydroxyl groups of (a2), (a3) and (a4), the isocyanate group ends can be obtained. can do.

Among the alicyclic diamine and / or the aliphatic diamine (b) used for the reaction with (a), the alicyclic diamine includes an alicyclic diamine having 6 to 18 carbon atoms [4,4′-diamino-3. , 3′-dimethyldicyclohexylmethane, 4,4′-diaminodicyclohexylmethane, diaminocyclohexane, isophoronediamine, etc.]; As the aliphatic diamine, an aliphatic diamine having 2 to 12 carbon atoms [ethylenediamine, propylenediamine, hexamethylenediamine, etc. And C8-15 aromatic aliphatic diamines [xylylenediamine, α, α, α ′, α′-tetramethylxylylenediamine, etc.], and the above compound is one kind or two or more kinds thereof. Can be used as a mixture of Of these, preferred are isophorone diamine and hexamethylene diamine.

The urethane resin particles (C) are most effective when the additive (N) contains at least the pigment particles (E) and is colored.
That is, in the urethane resin particles (C) composed of the urethane resin particles (P) and the pigment particles (E), the surface of the urethane resin particles (P) is obtained by mixing the urethane resin particles (P) and the pigment particles (E). The slush molding urethane resin particles (C) having pigment particles (E) attached thereto can be obtained. In the urethane resin particles (C), most of the mixed (E) adheres to the surface of (P), particularly the indented portion, so there is almost no aggregation of pigment particles, and 100 urethane resin particles (P). The hit has a feature that the particle diameter is 20 to 140 μm and the number of particles (F) which are aggregates of pigment particles (E) is 1 or less.

The urethane resin particles (C) of the present invention have a particle size of 20 to 140 μm per 100 urethane resin particles (P) and 1 or less particles (F) that are aggregates of pigment particles (E). It is desirable. The particles (F) are not limited to those produced by sliding or agglomerating the pigment particles (E) from the surface of the urethane resin particles (P), but are the stage before mixing with the urethane resin particles (P), that is, coloring. Those already agglomerated at the time, such as agent paste, pigment powder, and the like are also included. If the number of particles (F) is 1 or less per 100 urethane resin particles (P), the pigment will have good color development. Therefore, the urethane resin particles (C) themselves will develop color or when they are melt-molded. Is preferable because the amount of pigment used is small.

As a coloring method of the urethane resin particles (C) for slush molding in which the urethane resin particles (P) and the pigment particles (E) are mixed and the pigment particles (E) are adhered to the surfaces of the urethane resin particles (P), for example, a melting point Pigment dispersion (G) and urethane resin in which pigment particles (E) are dispersed in an organic compound (H) containing at least one ester group in a molecule having a boiling point of 0 ° C. or lower and a boiling point of 170 ° C. or higher A method of mixing the particles (P) is preferable. By performing this method, the urethane resin particles (C) can be colored efficiently and with good color reproducibility.

Since the organic compound (H) has good dispersion stability of the pigment particles (E), the pigment dispersion (G) can store the pigment (E) for a long time without causing aggregation of the pigment. . In addition, the pigment dispersion (G) composed of the organic compound (H) and the pigment particles (E) has a high affinity with the urethane resin particles (P). Therefore, the urethane resin particles (P) are obtained only with the pigment particles (E). ) On the particle surface in a short time and uniformly.

Examples of the organic compound (H) include the same compounds as those exemplified as the plasticizer.
Of these, preferred are benzoates, and particularly preferred is a dibenzoate of polyethylene glycol.

The slush molding urethane resin particles (C) of the present invention can be slush molded into a resin molded body. For slush molding, the box containing the resin powder composition of the present invention and a heated mold are both vibrated and rotated, the resin powder composition is melted and flowed in the mold, cooled and solidified, and molded. A method for producing a body (skin etc.) can be applied.
The temperature (° C.) of the mold is preferably 200 to 280 ° C.

The resin molding obtained by slush molding the resin powder composition of the present invention is suitable as an automobile interior material (instrument panel, door trim, etc.). For example, the thickness of the resin molded body (skin) molded with the resin powder composition of the present invention is preferably 0.3 to 1.2 mm. The molded body (skin) can be made into a resin molded product by setting the surface so as to be in contact with the foaming mold, pouring urethane foam, and forming a foam layer of 5 mm to 15 mm on the back surface.

In the case of a smooth surface with no irregularities on the surface, the generation of particles (F) that are aggregates of pigment particles (E) is remarkable, but the urethane resin particles (C) of the present invention have irregularities on the particle surface. Therefore, the pigment particles attached to the surface of the resin particles do not slide off from the surface or aggregate between the pigment particles on the particle surface due to the shear at the time of stirring and mixing in the coloring step or the subsequent step. Therefore, the color developability is good, and the problem that particles (F) that are aggregates of pigments are mixed in the product does not occur. Further, compared with a process of mixing with a pigment at the stage of a liquid raw material before particle formation, it is not necessary to carefully clean the production equipment for each color change of the product, so that productivity can be improved.

EXAMPLES Hereinafter, although an Example demonstrates this invention further more concretely, this invention is not limited to this. In the following, parts indicate parts by weight, and% indicates% by weight.

Production Example 1
A polybutylene adipate (575 parts) having a number average molecular weight (hereinafter referred to as Mn) of 1000 in a reaction vessel equipped with a production thermometer, a stirrer and a nitrogen blowing tube for the prepolymer solution (U-1), Mn 900 polyhexamethylene isophthalate (383 parts), 1-octanol (16.8 parts), kaolin (18.6 parts) with a volume average particle size of 9.2 μm were charged, and after nitrogen substitution, 110 ° C. with stirring. And then melted and cooled to 60 ° C. Subsequently, hexamethylene diisocyanate (242 parts) was added and reacted at 85 ° C. for 6 hours. Subsequently, after cooling to 60 ° C., tetrahydrofuran (217 parts) and a stabilizer (2.5 parts) [Irganox 1010 manufactured by Ciba Specialty Chemicals Co., Ltd.], an ultraviolet absorber (1.91 parts) [Ciba Specialty Chemicals, Inc .; Tinuvin 571] was added and mixed uniformly to obtain a prepolymer solution. The obtained prepolymer solution (U-1) had an NCO content of 2.2%.

Production Example 2
Production of MEK ketimine product of diamine Hexamethylenediamine and excess MEK (methyl ethyl ketone; 4-fold molar amount with respect to diamine) were refluxed at 80 ° C. for 24 hours, and the generated water was removed from the system. Thereafter, unreacted MEK was removed under reduced pressure to obtain a MEK ketiminate.

Production Example 3
Preparation of prepolymer solution (U-2) In a reaction vessel equipped with a thermometer, a stirrer and a nitrogen blowing tube, polybutylene adipate (1214 parts) with Mn of 1000, polyethylene phthalate with Mn of 900 (terephthalic acid / isophthalate) Acid = 50/50 (weight ratio)) (304 parts), 1-octanol (27.6 parts), kaolin (18.6 parts) having a volume average particle diameter of 9.2 μm, charged with nitrogen, and stirred. While being heated to 110 ° C., the mixture was melted and cooled to 60 ° C. Subsequently, hexamethylene diisocyanate (313.2 parts) was added and reacted at 85 ° C. for 6 hours. Next, after cooling to 60 ° C., tetrahydrofuran (425 parts), stabilizer (2.7 parts) [Irganox 1010], UV absorber (1.91 parts) [manufactured by Ciba Specialty Chemicals, Inc .; Tinuvin 571] was added and mixed uniformly to obtain a prepolymer solution. The NCO content of the obtained prepolymer solution (U-2) was 1.6%.

Example 1
Production reaction vessel for urethane resin particles (C-1) The prepolymer solution (U-1) (100 parts) obtained in Production Example 1 and the MEK ketimine compound (5.6 parts) are charged and mixed, and dispersed therein. 340 parts (amount of organic solvent in the aqueous solution: 20 weights) in which the agent (Sunspear PS-8 (1.3 parts) manufactured by Sanyo Chemical Industries, Ltd.) and tetrahydrofuran (dielectric constant: 8.2) (68 parts) are dissolved %) Was added and mixed for 1 minute at a rotational speed of 9000 rpm (peripheral speed: 15 m / s) using an ultradisperser manufactured by Yamato Scientific Co., Ltd. This mixture was transferred to a reaction vessel equipped with a thermometer, a stirrer and a nitrogen blowing tube, purged with nitrogen, and then reacted at 50 ° C. for 10 hours with stirring. After completion of the reaction, filtration and drying were performed to produce urethane resin particles (P-1). Mn of (P-1) was 25,000, the center particle size was 151 μm, and the 90% particle size / 10% particle size was 2.7.
100 parts of the obtained urethane resin particles (P-1), 1.0 part of carbon black as a colorant, 1.0 part of a dibenzoic acid ester of polyethylene glycol (degree of polymerization 2 to 10) (manufactured by Sanyo Chemical Industries) Pigment dispersion (G-1) (2.7 parts) dispersed in an organic compound (H-1) that is Sunsoft EB300, melting point: 0 ° C. or lower, boiling point: 300 ° C. or higher) is charged into a Henschel mixer. And stirred for 1 minute at a rotational speed of 700 min ⁻¹ . Next, the mixture was transferred to a 100 L Nauter mixer, and dipentaerythritol pentaacrylate (4.0 parts), a UV stabilizer (0.3 parts) [manufactured by Ciba Specialty Chemicals Co., Ltd .; For 4 hours. After 4 hours of impregnation, two types of internally added release agents {dimethylpolysiloxane (0.06 parts) [manufactured by Nippon Unicar Co., Ltd .; Kei L45-10000], carboxyl-modified silicon (0.05 parts) [Shin-Etsu Chemical Co., Ltd. X-22-37710]} was added and mixed for 1 hour, and then cooled to room temperature. Finally, an anti-blocking agent (0.5 part) [Gantz Kasei Co., Ltd .; Gantz Pearl PM-030S] (0.5 part) was added and mixed, passed through a 48 mesh sieve, and then a 200 mesh sieve. The slush-molding urethane resin particles (C-1) were obtained except for those that passed through.

Example 2
Production of urethane resin particles (C-2) Urethane resin particles (P-2) were produced by the same operation as in Example 1 except that 15 parts of sodium chloride was added to the aqueous solution instead of tetrahydrofuran. Mn of (P-2) was 25,000, the center particle size was 180 μm, and the 90% particle size / 10% particle size was 3.0.
Using (P-2) instead of (P-1) in Example 1, the same procedure as in Example 1 was carried out to obtain urethane resin particles for slush molding (C-2).

Example 3
An oil phase in which the prepolymer solution (U-1) (100 parts) obtained in Production Example 1 and a MEK ketimine compound (5.6 parts) were charged and mixed into a production reaction container for urethane resin particles (C-3), An aqueous solution in which a dispersing agent polyvinyl alcohol (manufactured by Kuraray Co., Ltd. (5.3 parts)) is dissolved is operated at a flow rate of 100 kg / hr and 400 kg / hr, respectively, while operating a TK pipeline homomixer (manufactured by Primix) at 3600 rpm The solution was fed to the dispersion. This mixture was transferred to a reaction vessel equipped with a thermometer, a stirrer and a nitrogen blowing tube, purged with nitrogen, and then reacted at 50 ° C. for 10 hours with stirring. After completion of the reaction, filtration and drying were performed to produce urethane primary particles (p-3). The thermal softening temperature of the primary particles (p-3) was 140 ° C., and the center particle size was 20 μm. Primary particles (p-3) were granulated by placing in a Henschel mixer (Mitsui Miike Chemical Co., Ltd.) and stirring at 40 m / sec. 15 minutes after the start of stirring, the temperature reached 140 ° C., and the operation was stopped at this stage to obtain urethane resin particles (P-3). Mn of (P-3) was 25,000, the center particle size was 180 μm, and the 90% particle size / 10% particle size was 2.9.
(P-3) was used instead of (P-1) in Example 1, and the others were carried out in the same manner as in Example 1 to obtain urethane resin particles for slush molding (C-3).

Example 4
Production Example 3 of Urethane Resin Particles (C-4) In Example 3 except that 1-4 butanediol (2.6 parts) was used instead of the MEK ketimine compound (5.6 parts), Urethane primary particles (p-4) were produced. The thermal softening temperature of the primary particles (p-4) was 91 ° C., and the center particle size was 3 μm.
The primary particles (p-4) were granulated by putting in a Henschel mixer (Mitsui Miike Chemical Co., Ltd.) and stirring at 40 m / sec. The temperature reached 90 ° C. 15 minutes after the start of stirring, and the operation was stopped at this stage to obtain urethane resin particles (P-4). Mn of (P-4) was 25,000, the center particle size was 20 μm, and the 90% particle size / 10% particle size was 3.0.
Using (P-4) instead of (P-1) in Example 1, omitting the process of “except for those passing through a 200-mesh sieve”, and otherwise performing in the same manner as in Example 1, urethane for slush molding Resin particles (C-4) were obtained.

Example 5
Production of Urethane Resin Particles (C-5) Urethane resin particles (P-5) were obtained by performing the same operations as in Example 3 except that the operation time of the Henschel mixer was changed to 25 minutes. Mn of (P-5) was 25,000, the center particle size was 500 μm, and the 90% particle size / 10% particle size was 3.0.
(P-5) is used instead of (P-1) in Example 1, and “26 mesh is used instead of the process of“ excluding those passing through a 48-mesh sieve after passing through a 48-mesh sieve ”” The other process was carried out in the same manner as in Example 1 to obtain slush molding urethane resin particles (C-5).

Example 6
Production reaction vessel for urethane resin particles (C-6) The prepolymer solution (U-2) (100 parts) obtained in Production Example 3 and the MEK ketimine compound (4.1 parts) are charged and mixed, and dispersed therein. 340 parts of aqueous solution (Sanyo Kasei Kogyo Co., Ltd. Sunspearl PS-8 (1.3 parts)) and methyl ethyl ketone (dielectric constant: 15.5) (68 parts) dissolved (amount of organic solvent in aqueous solution: 20 weight) %) Was added and mixed for 1 minute at a rotational speed of 9000 rpm (peripheral speed: 15 m / s) using an ultradisperser manufactured by Yamato Scientific Co., Ltd. This mixture was transferred to a reaction vessel equipped with a thermometer, a stirrer and a nitrogen blowing tube, purged with nitrogen, and then reacted at 50 ° C. for 10 hours with stirring. After completion of the reaction, filtration and drying were performed to produce urethane resin particles (P-6). Mn of (P-6) was 18,000, the center particle size was 143 μm, and the 90% particle size / 10% particle size was 2.8.
(P-6) was used instead of (P-1) in Example 1, and the others were carried out in the same manner as in Example 1 to obtain urethane resin particles for slush molding (C-6).

Example 7
An oil phase in which the prepolymer solution (U-1) (100 parts) obtained in Production Example 1 and the MEK ketimine compound (5.6 parts) were charged and mixed in a reaction vessel for producing urethane resin particles (C-7), An aqueous solution in which a dispersant (sodium dodecyl diphenyl ether disulfonate) (5.3 parts) was dissolved was added to a DISPAX-REACTOR (manufactured by IKA) at a flow rate of 100 kg / hr and 400 kg / hr at 12000 rpm. The solution was fed and dispersed. This mixture was transferred to a reaction vessel equipped with a thermometer, a stirrer and a nitrogen blowing tube, purged with nitrogen, and then reacted at 50 ° C. for 10 hours with stirring. After completion of the reaction, filtration and drying were performed to produce urethane primary particles (p-7).
The primary particles (p-7) had a heat softening temperature of 141 ° C. and a center particle size of 3 μm. Primary particles (p-7) were granulated by putting in a Henschel mixer (Mitsui Miike Chemical Co., Ltd.) and stirring at 40 m / sec. The temperature reached 140 ° C. 15 minutes after the start of stirring, and continued for 15 minutes and stopped after operation to obtain urethane resin particles (P-7). Mn of (P-7) was 25,000, the center particle size was 350 μm, and the 90% particle size / 10% particle size was 2.7.
(P-7) was used instead of (P-1) in Example 1, and the others were carried out in the same manner as in Example 1 to obtain urethane resin particles for slush molding (C-7).

Example 8
Production reaction vessel for urethane resin particles (C-8) The prepolymer solution (U-2) (100 parts) obtained in Production Example 3 and MEK ketimine compound (4.1 parts) are charged and mixed, and dispersed therein. 300 parts of an aqueous solution in which an agent (Sunspear PS-8 (1.3 parts) manufactured by Sanyo Chemical Industries, Ltd.) is dissolved is added and mixed for 1 minute at a rotation speed of 6000 rpm using an ultradisperser manufactured by Yamato Scientific Co., Ltd. did. This mixture was transferred to a reaction vessel equipped with a thermometer, a stirrer and a nitrogen blowing tube, purged with nitrogen, and then reacted at 50 ° C. for 10 hours with stirring. After completion of the reaction, filtration and drying were performed to produce urethane resin primary particles (p-8). The primary particles (p-8) had a heat softening temperature of 140 ° C. and a center particle size of 40 μm. Primary particles (p-8) were granulated by putting in a Henschel mixer (Mitsui Miike Chemical Co., Ltd.) and stirring at 40 m / sec. By stopping the operation when the temperature reached 140 ° C. 15 minutes after the start of stirring, urethane resin particles (P-8) were obtained. Mn of (P-8) was 25,000, the center particle size was 110 μm, and the 90% particle size / 10% particle size was 3.0.
(P-8) was used instead of (P-1) in Example 1, and the others were carried out in the same manner as in Example 1 to obtain urethane resin particles for slush molding (C-8).

Example 9
Production of Urethane Resin Particles (C-9) By performing the same operation as in Example 1 except that the amount of tetrahydrofuran used was changed to 34 parts (amount of organic solvent in aqueous solution: 10% by weight), urethane resin particles (P -9) was obtained. Mn of (P-9) was 25,000, the center particle size was 120 μm, and the 90% particle size / 10% particle size was 2.0.
(P-9) was used instead of (P-1) in Example 1, and the others were carried out in the same manner as in Example 1 to obtain urethane resin particles for slush molding (C-9).

Example 10
Production of urethane resin particles (C-10) Primary particles of urethane can be obtained by performing the same operation as in Example 7 except that the amount of dispersant (dodecyl diphenyl ether disulfonate sodium salt) used is changed to 7.5 parts. (P-10) was produced. The thermal softening temperature of the primary particles (p-10) was 141 ° C., and the center particle size was 2 μm. Furthermore, by performing the same operations as in Example 7, urethane resin particles (P-10) were obtained. Mn of (P-10) was 25,000, the center particle size was 250 μm, and the 90% particle size / 10% particle size was 3.0.
(P-10) was used instead of (P-1) in Example 1, and the others were carried out in the same manner as in Example 1 to obtain urethane resin particles for slush molding (C-10).

Example 11
Manufacture of polyurethane resin particles (C-11) Mn obtained from 1,4-BD and polyester glycol 243.5 parts of 1,000 Mn obtained from 1,4-BD and adipic acid, 1,4-BD, ethylene glycol and adipic acid 243.5 parts of a polyester diol of 2600 and 324.7 parts of a polyester diol of 1500 Mn obtained from 1,6-HG and isophthalic acid were mixed with 39.3 parts of 1,6-HG. A uniform glycol component was obtained. This glycol component and HDI were mixed and supplied from a hopper of a twin-screw extruder adjusted to a temperature of about 190 ° C. at a flow rate ratio of 100: 17.5, and resinification was performed simultaneously with kneading to obtain a polyurethane resin.

The polyurethane resin obtained in the above step is applied to a pelletizer, and 100 parts of the pelleted polyurethane resin is 0.25 parts of Irganox 245 (manufactured by Ciba Specialty Chemicals) as an antioxidant, and Tinuvin 213 as an ultraviolet absorber. 0.15 parts (manufactured by Ciba Specialty Chemicals), 0.15 part of tinuvin 765 (manufactured by Ciba Specialty Chemicals) as light stabilizer, and SH200-1,000CS (Toray Dow Corning) as internal release agent Was added from a hopper of a twin screw extruder whose temperature was adjusted to about 200 ° C., and kneaded to obtain a polyurethane resin.

The polyurethane resin to which the additive was added as described above was cooled to −150 ° C. with liquid nitrogen, and made into a fine powder by an impact pulverizer. In order to impart fluidity to this, 0.4 part of the dusting agent “MP-1451” is added to 100 parts of the resin, and stirred and mixed so as to uniformly adhere to the surface of the polyurethane resin. The sieve was passed through to obtain polyurethane resin primary particles (p-11). (P-11) had a heat softening temperature of 110 ° C. and a center particle size of 50 μm. Primary particles (p-11) were granulated by putting in a Henschel mixer (Mitsui Miike Chemical Co., Ltd.) and stirring at 40 m / sec. 15 minutes after the start of stirring, the temperature reached 110 ° C., and the operation was stopped at this stage to obtain urethane resin particles (P-11). Mn of (P-11) was 25,000, the center particle size was 180 μm, and the 90% particle size / 10% particle size was 3.0.
(P-11) was used instead of (P-1) in Example 1, and the others were carried out in the same manner as in Example 1 to obtain urethane resin particles for slush molding (C-11).

Comparative Example 1
Production of polyurethane resin particle C′-1 <Synthesis of thermoplastic polyurethane resin>
In a reaction vessel equipped with a nitrogen introduction tube, a thermometer, a cooling tube and a stirrer, 75.2 parts Takelac U-2024 (Mitsui Chemical Polyurethane, Polyester Polyol) as a polyol and Irganox 245 (Ciba Specialty) as an antioxidant Chemicals) 0.05 parts, monool 2-ethylhexyl alcohol (Wako Pure Chemical Industries, Ltd.) 0.49 parts, isocyanate 4,4'-methylenebis (cyclohexyl isocyanate) (Sumika Bayer Urethane Co., Ltd.) , Trade name: Death Module W) 21.6 parts was charged, the temperature was raised to 80-85 ° C. with good stirring, and the reaction was continued for about 3.5 hours, after which the NCO wt% was 3.6 wt%. It was confirmed that it was lowered to an isocyanate group-terminated prepolymer.
Thereafter, 0.45 part of the dispersion stabilizer (I) and 29.2 parts of n-heptane, which had been mixed in advance, were charged all at once into the reaction vessel, and the isocyanate group-terminated prepolymer was dispersed over 1 hour. .

Then, 58.4 parts of n-heptane was charged at a rate of 30 ml / min, and then the reaction temperature was lowered to 25 ° C. A chain extender prepared by previously dispersing 2.7 parts of a 70% by weight aqueous solution of 1,6-hexamethylenediamine in 0.06 part of dispersion stabilizer (I) and 3.86 parts of n-heptane. The dispersion was charged all at once.
After completion of the charging, the reaction was carried out at 25 to 35 ° C. for 30 minutes, then the temperature was raised to 45 ° C., then the reaction was continued for 30 minutes at the same temperature, and finally the reaction temperature was raised to 80 to 85 ° C. By reacting for a time, a dispersion of a thermoplastic polyurethane resin was obtained.
After mixing so that styrene and methyl methacrylate become 60% by weight and 40% by weight, respectively, α-methylstyrene dimer that becomes 0.5 parts is added to 100 parts of these monomers, and further mixed uniformly. And 100 parts by weight of the total monomer (total amount of styrene and methyl methacrylate), dimethyl 2,2′-azobis (2-methylpropionate) (trade name, manufactured by Wako Pure Chemical Industries, Ltd.) as a radical polymerization initiator. : V-601) was added to prepare a monomer solution.
The monomer liquid was charged all together at a reaction temperature of 30 ° C. into the dispersion of the thermoplastic polyurethane resin obtained above so that the total amount of the monomer was 20 parts by weight with respect to 100 parts by weight of the thermoplastic polyurethane resin. . Thereafter, the temperature was gradually raised, and finally, an aging reaction was performed at a reaction temperature of 80 ° C. for 12 hours.
Thereafter, 0.5 parts of TINUVIN 213 (manufactured by Ciba Specialty Chemicals) as a benzotriazole-based ultraviolet absorber and 0.5 part of TINUVIN 765 (manufactured by Ciba Specialty Chemicals) as a hindered amine light-resistant stabilizer were added to 100 parts of a thermoplastic polyurethane resin. 5 parts, 6 parts of a mixture of dipentaerythritol hexaacrylate and dipentaerythritol pentaacrylate (trade name: Kayarad DPHA, manufactured by Nippon Kayaku Co., Ltd.) as a heat-crosslinkable monomer, p-methoxyphenol as a polymerization inhibitor, heat-crosslinkable The thermoplastic polyurethane resin dispersion was charged so as to be 1 part with respect to 100 parts of the monomer and mixed for 30 minutes.

Subsequently, the dispersion was cooled to 30 ° C. or lower, and a solid content was collected by filtration.
Next, 100 parts of a solid content, 0.5 part of TSF-451-3000 (GE Toshiba Silicone Silicone Oil) and 0.3 part of an antiblocking agent are charged into a Nauter mixer dryer. The mixture was dried at 40 ° C. for 3 hours with stirring under reduced pressure. Then, after cooling the content to 25 degrees C or less, it discharged | emitted and the particulate polyurethane resin composition (P'-1) was obtained. The central particle size of (P′-1) was 135 μm.
100 parts of the obtained particulate polyurethane resin composition, 0.6 parts of carbon black / calcium carbonate dispersion (manufactured by Sumika Color Co., Ltd., trade name: PV-817) and 0.4 parts of carbon black / A calcium carbonate dispersion (manufactured by Sumika Color Co., Ltd., trade name: PV-801) was put into a Henschel mixer and stirred at a rotational speed of 700 min ⁻¹ for 1 minute. After passing through a 48-mesh sieve, a particulate polyurethane resin composition (C′-1) was obtained except for those passing through a 200-mesh sieve.

Comparative Example 2
Production of Polyacrylic Resin Particle C′-2 The following operation was performed to obtain an acrylic block copolymer precursor. After replacing the inside of the 500 L pressure-resistant reactor with nitrogen, 692 parts (4.82 mol) of copper bromide, 77800 parts (607 mol) of BA and 3470 parts (27.1 mol) of TBA were charged, and stirring was started. Thereafter, a solution prepared by dissolving 965 parts (2.68 mol) of diethyl 2,5-dibromoadipate in 7140 parts of acetonitrile (nitrogen bubbling) was charged, and the inner solution was heated to 75 ° C. for 30 minutes. Stir. When the internal temperature reached 75 ° C., 83.6 parts (0.482 mol) of a ligand pentamethyldiethylenetriamine was added to initiate polymerization of the acrylic polymer block.
During polymerization, the polymerization rate was controlled by adding pentamethyldiethylenetriamine as needed. Pentamethyldiethylenetriamine was added twice in total (168 parts in total) during the acrylic polymer block polymerization.
When the conversion rate of BA was 99.0% and the conversion rate of TBA was 99.3%, MMA 49600 parts (495 mol), EA 8050 parts (80.4 mol), copper chloride 478 parts (4.82 mol), The polymerization of the methacrylic polymer block was started by adding 83.6 parts (0.482 mol) of pentamethyldiethylenetriamine and 106900 parts of toluene (nitrogen bubbled). During polymerization, the polymerization rate was controlled by adding pentamethyldiethylenetriamine as needed. Pentamethyldiethylenetriamine was added a total of 6 times (a total of 502 parts) during methacrylic polymer block polymerization. When the conversion rate of MMA was 96.1%, 250,000 parts of toluene was added, and the reactor was cooled to complete the reaction. The number average molecular weight Mn of the obtained block copolymer was 77500.
Toluene was added to the resulting reaction solution to make the polymer concentration 25% by weight. 2200 parts of p-toluenesulfonic acid was added to this solution, the inside of the reactor was purged with nitrogen, and the mixture was stirred at 30 ° C. for 3 hours. The reaction solution was sampled to confirm that the solution was colorless and transparent, and 6630 parts of Radiolite # 3000 manufactured by Showa Chemical Industry Co., Ltd. was added. Thereafter, the reactor was pressurized to 0.1 to 0.4 MPaG with nitrogen, and the solid content was separated using a pressure filter equipped with a polyester felt as a filter medium (filtration area 0.45 m ² ).

To about 450,000 parts of the obtained block copolymer solution after filtration, 675 parts of an antioxidant (manufactured by Ciba Specialty Chemicals Co., Ltd., Irganox 1010) was added and dissolved. The inside of the machine was purged with nitrogen, stirred at an internal temperature of 150 ° C. for 2 hours, and then cooled to 60 ° C. 1310 parts of Kyoward 500SH was added, the inside of the reactor was purged with nitrogen, and the mixture was stirred at 30 ° C. for 2 hours. The reaction solution was sampled to confirm that the solution was neutral, and the reaction was completed. Thereafter, the reactor was pressurized to 0.1 to 0.4 MPaG with nitrogen, and the solid content was separated using a pressure filter (filter area 0.45 m ² ) equipped with polyester felt as a filter medium to obtain a polymer solution. It was. 200000 parts of the obtained polymer solution was reduced in pressure to 0.03 MPa while controlling the temperature of the solution at 70 ° C. to 75 ° C. in a 500 L pressure-resistant reactor with a condenser to remove the whole amount of acetonitrile and a part of toluene. As a result, the polymer solution concentration was adjusted to 50% by weight.

26250 parts of the obtained polymer solution, 26750 parts of toluene, epoxy group-containing acrylic polymer ((Toagosei Co., Ltd., ARUFON XG4010; containing 4 epoxy groups on average per molecule (calculated from catalog data)) 1310 parts, plasticizer (manufactured by Asahi Denka Co., Ltd., RS700), 1310 parts, lubricant (manufactured by Nippon Oil & Fats Co., Ltd., beef tallow extremely hardened oil) 131 parts, pure water 10500 parts and polyvinyl alcohol surfactant (Nippon Synthetic Chemical) KH-17 (manufactured by Kogyo Co., Ltd.), 131 parts (4380 parts added as a 3% aqueous solution) was charged into a 200 L pressure stirrer, and the temperature was increased by blowing steam from the bottom of the stirring tank while stirring at 250 rpm. The solvent gas was introduced into the condenser and the solvent was sequentially recovered, and the steam injection was stopped 5 minutes after the liquid temperature reached 95 ° C. By passing water through the jacket, the liquid temperature was cooled to 60 ° C., followed by centrifugal dehydration, and after dehydration, a spherical powder with an average particle size of 210 μm and a moisture content of 20% was obtained. 120 g of organic particles (Nippon Shokubai Co., Ltd., Epostor MA1002) 120 g were added to 3750 g of 20% powder by hand blending, dried in a batch fluid dryer at a resin temperature of up to 50 ° C. P′-2) was obtained.

100 parts of the obtained particulate polyacrylic resin powder (P′-2), 0.6 parts of carbon black / calcium carbonate dispersion (manufactured by Sumika Color Co., Ltd., trade name: PV-817) and 0. 4 parts of carbon black / calcium carbonate dispersion (manufactured by Sumika Color Co., Ltd., trade name: PV-801) was put into a Henschel mixer and stirred at a rotational speed of 700 min ⁻¹ for 1 minute. Next, after passing through a 48-mesh sieve, particulate polyacrylic resin particles (C′-2) were obtained except for those passing through a 200-mesh sieve.

Comparative Example 3
The prepolymer solution (U-1) (100 parts) obtained in Production Example 1 and the MEK ketimine compound (5.6 parts) are charged and mixed in a reaction vessel for production of polyurethane resin particles (C′-3). 300 parts of an aqueous solution in which a dispersing agent (Sanyo Pearl PS-8 (1.3 parts) manufactured by Sanyo Chemical Industries, Ltd.) is dissolved is added, and 1 minute at a rotational speed of 5000 rpm using an ultradisperser manufactured by Yamato Scientific Co., Ltd. Mixed. This mixture was transferred to a reaction vessel equipped with a thermometer, a stirrer and a nitrogen blowing tube, purged with nitrogen, and then reacted at 50 ° C. for 10 hours with stirring. After completion of the reaction, filtration and drying were performed to produce urethane resin particles (P′-3). Mn of (P′-3) was 25,000, the center particle size was 150 μm, and the 90% particle size / 10% particle size was 3.5.
Using (P′-3) instead of (P-1) in Example 1, the same procedure as in Example 1 was carried out to obtain urethane resin particles for slush molding (C′-3).

Comparative Example 4
Production of polyurethane resin particles (C′-4) From 243.5 parts of polyester diol having a Mn of 1,000 obtained from 1,4-BD and adipic acid, 1,4-BD, ethylene glycol and adipic acid 243.5 parts of a polyester diol having an Mn of 2,600, 324.7 parts of a polyester diol having an Mn of 1,500 obtained from 1,6-HG and isophthalic acid, A uniform glycol component was prepared by mixing with 6-HG. This glycol component and HDI were mixed and supplied from a hopper of a twin-screw extruder adjusted to a temperature of about 190 ° C. at a flow rate ratio of 100: 17.5, and resinification was performed simultaneously with kneading to obtain a polyurethane resin.

The polyurethane resin obtained in the above step is applied to a pelletizer, and 100 parts of the pelleted polyurethane resin is 0.25 parts of Irganox 245 (manufactured by Ciba Specialty Chemicals) as an antioxidant, and Tinuvin 213 as an ultraviolet absorber. 0.15 parts (manufactured by Ciba Specialty Chemicals), 0.15 part of tinuvin 765 (manufactured by Ciba Specialty Chemicals) as light stabilizer, and SH200-1,000CS (Toray Dow Corning) as internal release agent Was added from a hopper of a twin screw extruder whose temperature was adjusted to about 200 ° C., and kneaded to obtain a polyurethane resin.

The polyurethane resin to which the additive was added as described above was cooled to about −150 ° C. with liquid nitrogen and made into a fine powder by an impact pulverizer. In order to impart fluidity to this, 0.4 part of the dusting agent “MP-1451” is added to 100 parts of the resin, and the mixture is stirred and mixed so as to uniformly adhere to the surface of the polyurethane resin. After passing through a sieve, polyurethane resin particles (P′-4) were obtained except for those passing through a 200-mesh sieve. The central particle size of (P′-4) was 180 μm, and the 90% particle size / 10% particle size was 6.5.

Furthermore, by performing the same operation as in Example 1, urethane resin particles for slush molding (C′-4) were obtained.

Comparative Example 5
Manufacture of vinyl chloride resin particles (C'-5) 100 parts of vinyl chloride resin (ZEST1000Z manufactured by Shin Daiichi Vinyl Co., Ltd.), 2.7 parts of pigment dispersion (G-1), epoxidized soybean oil (Corporation) 5 parts of ADEKA O-130P), 5 parts of hydrotalcite (Alkamizer 5 manufactured by Kyowa Chemical Industry Co., Ltd.), 1 part of zeolite (Mizusawa DS manufactured by Mizusawa Chemical Industry Co., Ltd.), stearoyl benzoylmethane (Showa Denko ( Karenz DK-1) 0.3 part was added to a Henschel mixer, mixed at a rotational speed of 700 min ⁻¹ , and when the temperature of the mixture rose to 80 ° C., a plasticizer (Trimerix manufactured by Kao Corporation) After adding 80 parts of NSK), the plasticizer was absorbed into the vinyl chloride resin and mixed until the above mixture further increased to obtain vinyl chloride resin particles (C′-5).

Comparative Example 6
Production of urethane resin particles (C′-6) The same procedure as in Example 7 was carried out except that the amount of dispersant used (sodium dodecyl diphenyl ether disulfonate) was changed to (11.0 parts). Primary particles (p′-6) were produced. The central particle diameter of the primary particles (p′-6) was 1 μm. Furthermore, by performing the same operations as in Example 7, urethane resin particles (P′-6) were obtained. Mn of (P′-6) was 25,000, the center particle size was 190 μm, and the 90% particle size / 10% particle size was 2.7.
100 parts of the obtained urethane resin particles (P′-6) and the pigment dispersion (G-1) (2.7 parts) as a colorant were put into a Henschel mixer and stirred at a rotational speed of 700 min ⁻¹ for 1 minute. did. Next, after passing through a 48-mesh sieve, except for those passing through a 200-mesh sieve, urethane resin particles for slush molding (C′-6) were obtained.

Comparative Example 7
Production of Urethane Resin Particles (C′-7) By performing the same operation as in Example 5 except that the peripheral speed of the Henschel mixer is changed to 0.4 m / s, urethane resin particles (P′-7) are obtained. It was. Mn of (P′-7) was 25,000, the center particle size was 180 μm, and the 90% particle size / 10% particle size was 4.0.
100 parts of the obtained urethane resin particles (P′-7) and the pigment dispersion (G-1) (2.7 parts) as a colorant were put into a Henschel mixer and stirred at a rotational speed of 700 min ⁻¹ for 1 minute. did. Next, after passing through a 48-mesh sieve, except for those passing through a 200-mesh sieve, urethane resin particles for slush molding (C′-7) were obtained.

Production of Resin Molded Product (Q) Slush molding was performed as follows. In Comparative Examples 1 and 2, the slush molding resin particles (C1) of Examples 1 to 11 and Comparative Examples 1 to 7 were applied to a Ni electromold having a wrinkle pattern heated to 270 ° C. in the other cases and 230 ° C. otherwise. (C11), (C′1) to (C′7) are filled, and after 10 seconds, the excess resin powder composition is discharged. After cooling for 60 seconds, the product was cooled with water and demolded from the Ni electroforming mold to obtain resin moldings (Q1) to (Q11) and (Q′1) to (Q′7) as skins.

By the method described below, the physical properties of the resin particles (C) and the number of particles (F) that are aggregates of the pigment particles (E), color fading, and skin are evaluated. I wrote.

<Shape factors SF1, SF2>
The shape factors SF1 and SF2 are measured with a scanning electron microscope (S-800: manufactured by Hitachi, Ltd.). Particles were photographed 80 times, particles of 150 μm or more and less than 300 μm at a magnification of 40 times, particles of 300 μm or more were photographed at 25 times, and 80 particles were randomly selected from the obtained image (resolution: 1280 × 1024 pixels). This was selected and introduced into an image analyzer (LUSEX3: manufactured by Nireco) for analysis, and average SF1 and SF2 values were calculated.

<Center particle size>
Using a Microtrac HRA particle size analyzer 9320-X100 (manufactured by Nikkiso Co., Ltd.), the particle size of 50% under sieving was measured by a laser light scattering method to obtain the central particle size.

<Glass transition temperature>
A film was prepared using the resin particles (C) under the same conditions as in the following color fading test. The dynamic viscoelasticity of the film was raised at a constant speed under the following conditions using a dynamic viscoelasticity measuring device Rheogel-E4000 manufactured by UBM Co., Ltd., and the peak top temperature of the loss elastic modulus E ″ was adjusted. The glass transition temperature was taken.
Measurement conditions: Frequency: 10Hz
Temperature range: -90 to 140 ° C
Temperature increase rate: 5 ° C / min

<Melting point>
The melting point was a constant temperature increase under the following conditions using a flow tester CFT-500 manufactured by Shimadzu Corporation, and the melting point was defined as the temperature at which the outflow amount was halved.
Load: 5kg
Die: 0.5mmΦ-1mm
Temperature increase rate: 5 ° C./min.

<Flow time>
Using a bulk specific gravity measuring instrument (JIS-K6720 compliant) manufactured by Tsutsui Rika Co., Ltd., the time required for 100 cm ³ of material to flow down the funnel was measured and used as an indicator of powder flowability. The flow-down time ≦ 20 seconds was regarded as acceptable powder flowability.

<Number of particles (F) that are aggregates of pigment particles (E)>
Using a microscope, the surface of a total of 400 resin particles is observed at a magnification of 100 times, and particles (F) that are aggregates of pigment particles (E) that are visually observed on a monitor projected at 100 times. ).

<Color fading>
After the surface temperature of the A4 size iron plate placed on the hot plate was set to 250 ° C., 50 g of the obtained resin particles were placed, the surface was leveled so that the film thickness was uniform, and 90 ° C. after 90 seconds. It cooled in the water bath, and the leveled resin film was peeled off from the iron plate. A test piece having a width of about 40 mm and a length of about 200 mm is cut out from the film and attached to a flat surface wear tester (model number FR-T, manufactured by Suga Test Instruments), and a white cotton cloth is placed on the friction element and fixed. The test piece was reciprocated 100 times with a load of 300 g of the friction element, and the color fading was evaluated. A white cotton cloth with no color was evaluated as ◯, and an attached one was evaluated as ×.

<Pinhole property>
The surface of the molded product (Q) was observed with a microscope (magnification: 10 times) to examine the occurrence of pinholes. It evaluated as pinhole property (circle) by 20 pinholes or less in the area | region of 10 cm x 10 cm.

Tables 1 and 2 show the evaluation results. In general, the fluidity of the powder depends on the center particle diameter and the particle shape. However, when Example 3 and Comparative Example 5 are compared, when compared with the same center particle diameter, the urethane resin is the same as the PVC resin particles. Compared to the large shape factor SF1, it became clear that the powder fluidity was equivalent. In addition, since the urethane resin particles of the present invention generate very little particles (F) that are pigment aggregates, when the particles are used as a molding material, the color developability is good and foreign matter can be reduced. In addition, since the dispersibility of the pigment is good, a high-quality molded product with less color transfer can be obtained even when the molded product is wiped with a cloth or the like.
When the slush molding is performed using the urethane resin particles for slush molding of the present invention, a high quality molded body with less defects such as pinholes and undercuts can be obtained.

The present invention relates to slush molded urethane resin particles. It can be suitably used as a material useful for slush molding, which is excellent in powder flowability, heat melting property, flexibility and durability.

Claims (10)

Urethane resin particles containing urethane resin (D) and additive (N), wherein the urethane resin particles have a shape factor SF1 of 101 to 200, a shape factor SF2 of 120 to 240, and a central particle Urethane resin particles for slush molding (C) having a diameter of 20 to 500 μm. The resin particles (C) according to claim 1, which are granulated. The urea group concentration of the urethane resin (D) is 0.5 to 10% by weight, the total of the urethane group concentration and the urea group concentration is 4 to 20% by weight, and the melting point is 160 to 260 ° C., and The urethane resin particles (C) according to claim 1 or 2, wherein the glass transition temperature is -65 to 0 ° C. Isocyanate in which urethane resin (D) is derived from aliphatic diisocyanate (a1), monool (a2), high molecular diol (a3) having a number average molecular weight of 500 to 10,000, and optionally low molecular diol (a4) The urethane according to any one of claims 1 to 3, which is a thermoplastic urethane resin obtained by reacting a group-terminal urethane prepolymer (a) with an alicyclic diamine and / or an aliphatic diamine (b). Resin particles (C). It contains urethane resin particles (P) and pigment particles (E) as an additive (N). The pigment particles (E) are adhered to the surfaces of the urethane resin particles (P), resulting in resin particles (P) 100. The resin particle (C) according to any one of claims 1 to 4, wherein the resin particle (C) has a particle size of 20 to 140 µm per particle and contains no more than one particle (F) that is an aggregate of pigment particles (E). . Pigment particles in an organic compound (H) containing at least one ester group in the molecule having a melting point of 0 ° C. or lower and a boiling point of 170 ° C. or higher as urethane resin particles (P) and additives (N) The pigment dispersion (G) in which (E) is dispersed, and the pigment dispersion (G) is adhered to the surface of the urethane resin particles (P). Resin particles (C). The urethane resin particles (C) according to any one of claims 1 to 6, comprising the urethane resin particles (P) and the pigment particles (E) as additives (N), wherein (P) and (E) And coloring the urethane resin particles for slush molding (C), wherein (E) is adhered to the surface of (P). The urethane resin particles (C) according to any one of claims 1 to 6, which contains pigment particles (E) as urethane resin particles (P) and additives (N), and have a melting point of 0 ° C or lower. In addition, a pigment dispersion (G) in which (E) is dispersed in an organic compound (H) containing at least one ester group in a molecule having a boiling point of 170 ° C. or higher is mixed with (P). A method for coloring urethane resin particles (C) for slush molding, wherein (G) is adhered to the surface of the slush. A urethane resin molded product obtained by slush molding the urethane resin particles (C) according to any one of claims 1 to 8. The molded article according to claim 9, which is a skin and has a thickness of 0.3 to 1.2 mm.