JPH0718115A - Resin molding and its production - Google Patents

Abstract

PURPOSE:To produce a resin molding having a natural stone-like visual appearance excellent in design and exhibiting a sufficiently high mechanical strength and to provide a method for readily producing such a resin molding. CONSTITUTION:The resin molding containing 15 to 60wt.% binder resin composition and 40 to 85wt.% powdery artificial marble is produced by polymerizing and curing a mixture containing a binder resin composition such as a polymerizable syrup and a powdery artificial marble in a pressurized shaped state.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin molded product having a natural stone-like appearance and a method for producing the same, more specifically, a resin molded product having excellent design and capable of effectively utilizing waste material of artificial marble. The present invention relates to a product and a manufacturing method thereof.

[0002]

2. Description of the Related Art Natural marble is limited in its production area and is expensive, and the size and shape of the product is limited by the size and shape of the rough stone. Therefore, melamine decorative boards, gel-coated artificial marble, and acrylic are used as alternative materials. Various artificial materials such as artificial artificial marble and unsaturated polyester artificial marble have been used. Among them, acrylic artificial marble and unsaturated polyester artificial marble are composed of acrylic resin or unsaturated polyester resin and inorganic filler, and are excellent in strength, impact resistance and processability, and have an elegant texture. It is widely used for various purposes such as kitchen tops, vanities, wall materials and floor materials.

[0003]

When manufacturing artificial marble or molded products thereof, a large amount of waste materials such as scraps, powder particles, defective products, etc. are generated, and these waste materials are usually discarded. However, as the amount of artificial marble used increases, the amount of waste material also increases, and the problem of waste material treatment has also arisen from the viewpoint of environmental problems such as dust problems. In addition, similar problems have arisen in the processing of collected used items and the like. An object of the present invention is to provide a resin molded product having a natural stone-like appearance that is excellent in designability and a method for manufacturing the same, while effectively utilizing such waste materials and recovered products of artificial marble.

[0004]

That is, the resin molded article of the present invention is characterized by containing 15 to 60% by weight of a binder resin composition and 40 to 85% by weight of artificial marble powder. is there. In addition, the method for producing a resin molded product of the present invention comprises an acrylic polymerizable syrup 15 to 15 comprising a (meth) acrylic monomer and a (meth) acrylic polymer
It is characterized in that a mixture containing 60% by weight and 40 to 85% by weight of artificial marble powder is polymerized and cured in a state of being pressed.

The resin molded product of the present invention is obtained by molding and solidifying an artificial marble powder with a resin composition as a binder. By incorporating the artificial marble powder in the resin molded product, a natural stone-like appearance excellent in design is obtained. And a resin molded article having the above. In the present invention, the binder resin composition is 15 to 60% by weight, and the artificial marble powder is 4%.
By setting the content in the range of 0 to 85% by weight, a resin molded product having a natural stone-like appearance excellent in designability and sufficient mechanical strength can be obtained. This is because when the content of the artificial marble powder is less than 40% by weight, the appearance of the resin molded product is poor in design, and when it exceeds 85% by weight, the mechanical strength of the resin molded product decreases.

The composition of the artificial marble powder used in the present invention is not particularly limited, and the commonly used acrylic resin, unsaturated polyester resin, and other resin components are used as inorganic fillers. There is no particular limitation as long as it is obtained by crushing a normal artificial marble in which is mixed. Further, the particle size of the artificial marble powder is appropriately selected according to the appearance of the resin molded product, and it is possible to use only a coarsely pulverized product or a fine powder having a large particle size, or to mix the two or use them with an appropriate particle size distribution. However, it is particularly preferable to use artificial marble powder having a particle size of 150 mesh or less from the viewpoints of moldability and mechanical properties of the resin molded product.

As the resin component used in the artificial marble powder, an acrylic resin is particularly preferable in terms of processability, impact resistance, weather resistance and flame retardancy. As the acrylic resin, one containing 80% by weight or more of methyl methacrylate is preferable, and for example, a methyl methacrylate homopolymer consisting only of methyl methacrylate monomer, or methyl obtained by copolymerizing methyl methacrylate monomer and other copolymerizable monomer Examples thereof include methacrylate copolymers. As the copolymerizable monomer to be copolymerized with methyl methacrylate, vinyl acetate, styrene, methyl acrylate,
Α, β such as ethyl acrylate, butyl acrylate, cyclohexyl acrylate, ethyl methacrylate, butyl methacrylate, cyclohexane methacrylate
Examples thereof include ethylenically unsaturated compounds, and one or more of these can be copolymerized.

As inorganic fillers, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium silicate, calcium silicate, aluminum silicate, aluminum stearate, glass, talc, quartz, silica, mullite, diatomaceous earth, gypsum, colloidal asbestos , Clay minerals, chalk, peacock stone, marble, limestone, anhydrite, boraxite, borax, mica, obsidian powder, crushed stone, etc.,
These may be used alone or in combination of two or more. Among these, hydroxides such as aluminum hydroxide, calcium hydroxide, and magnesium hydroxide are preferable because they release crystal water at high temperature and effectively act to improve flame retardancy, and aluminum hydroxide is particularly preferable. is there. The particle size of these inorganic fillers is preferably in the range of 1 to 150 μm, more preferably 30 to 80 μm.
Is the range. Further, as the inorganic filler, those whose surface is treated with a silane coupling agent, a titanate coupling agent, stearic acid or the like can be used. In the present invention, the artificial marble powder preferably contains 20 to 85% by weight of a resin component and 15 to 80% by weight of an inorganic filler, and more preferably the resin component 20.
The range is ˜60 wt% and the inorganic filler is 40-80 wt%.

Examples of the binder resin composition used in the present invention include acrylic resins, vinyl ester resins, unsaturated polyester resins, phenol resins,
An epoxy resin, a melamine resin, etc. are mentioned. Among them, acrylic resins are particularly preferable from the viewpoint of weather resistance of molded products. Acrylic binder resins include homopolymers of (meth) acrylic acid esters such as methylmethacrylate, and (meth) methacrylates such as methylmethacrylate.
Examples thereof include copolymers of acrylic acid esters with α, β-ethylenically unsaturated compounds, polyfunctional (meth) acrylic acid esters and the like, and those containing 80% by weight or more of methyl methacrylate units are particularly preferable.

As the (meth) acrylic acid ester,
Methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, (meth)
(Meth) acrylic alkyl ester such as t-butyl acrylate, cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, nonyl (meth) acrylate, lauryl (meth) acrylate, and (meth) acrylic acid 2 -(Meth) acrylic acid hydroxyalkyl ester such as -hydroxyethyl, 2-hydroxypropyl (meth) acrylic acid, and 2-hydroxybutyl (meth) acrylic acid. Examples of the α, β-ethylenically unsaturated compound include vinyl acetate and styrene, in addition to the above (meth) acrylic acid ester.

Further, as the polyfunctional (meth) acrylic acid ester, ethylene glycol di (meth) acrylate, 1,2-propylene glycol di (meth) acrylate, 1,3-butylene glycol di (meth) acrylate, 1, Alkanediol di (meth) acrylate such as 6-hexanediol di (meth) acrylate, diethylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) ) Acrylate, polyoxyalkylene glycol di (meth) acrylate such as polyethylene glycol di (meth) acrylate, divinylbenzene,
Diallyl phthalate, triallyl cyanurate, triallyl isocyanurate, allyl (meth) acrylate,
Examples thereof include diallyl fumarate, trimethylolpropane tri (meth) acrylate, and pentaerythritol tetra (meth) acrylate.

In the resin molded product of the present invention, in addition to the binder resin composition and artificial marble powder described above, if necessary, a fibrous filler such as glass fiber, an inorganic filler, a pigment, a dye or the like is colored. Agent, UV absorber, flame retardant, release agent,
You may mix | blend additives, such as antioxidant. The resin molded article of the present invention can be formed by molding a mixture of the binder resin composition and artificial marble powder as described above by various molding methods such as heat pressure molding, room temperature pressure molding, injection molding, and pultrusion molding. However, it is preferably manufactured by heat pressure molding or room temperature pressure molding. Below, the manufacturing method of the resin molded product of this invention is demonstrated.

First, artificial marble composed of a resin component and an inorganic filler is crushed into particles of, for example, 150 mesh or less using a crusher such as a roll crusher, and if necessary, classified to obtain artificial marble powder having a desired particle size. obtain. The obtained artificial marble powder and the binder resin composition are uniformly mixed using a conventional ribbon blender, a rotary mixer or the like. Then, the mixture of the artificial marble powder and the binder resin composition is spontaneously flowed into the cavity of the molding die under pressure,
Fill by a method such as vibration filling. After the mixture is filled in the molding die, the molding die is pressed to mold the mixture and polymerize and cure to obtain a resin molded product. The pressure at this time is preferably 50 to 200 Kg / cm ² . The polymerization and curing may be carried out by leaving it at room temperature or by heating it. In the case of polymerizing and curing by heating, heating and pressurization can be simultaneously performed using a hot press device or the like. The heating and pressurizing conditions are a temperature of 50 to 150 ° C and a pressure of 50 to 200K.
The g / cm ² and the molding cycle are set to about 2 to 5 minutes.
Preferably, the temperature is 70 to 130 ° C and the pressure is 70 to 150K.
It is in the range of g / cm ² . The obtained resin molded product is taken out of the molding die and, if necessary, subjected to a treatment such as surface polishing. The resin molded product thus obtained has a natural stone-like appearance that is excellent in mechanical strength and the like and is excellent in design.

As the acrylic binder resin used as the binder resin composition in the present invention, an acrylic polymerizable syrup obtained by dissolving and containing a low molecular weight prepolymer in a polymerizable monomer is particularly preferable. Acrylic polymerizable syrup can be obtained by dissolving a preliminarily prepared prepolymer in a polymerizable monomer, or by immediately polymerizing the polymerizable monomer until a desired viscosity is reached, and then immediately stopping the polymerization. The viscosity is preferably adjusted to 10,000 cps or less, more preferably 50,000 cps or less. In particular, an acrylic polymerizable syrup composed of a (meth) acrylic acid ester monomer, a (meth) acrylic acid ester polymer, a multi-functional (meth) acrylic acid ester monomer and the like is preferable.

Examples of the (meth) acrylic acid ester monomer include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, and isobutyl (meth) acrylate. ,
(Meth) acrylic alkyl ester such as t-butyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, nonyl (meth) acrylate, and lauryl (meth) acrylate; 2-hydroxyethyl acrylate, 2-hydroxypropyl (meth) acrylate, 2- (meth) acrylic acid
Examples thereof include (meth) acrylic acid hydroxyalkyl esters such as hydroxybutyl, and these monomers can be used alone or in combination of two or more kinds.
These (meth) acrylic acid ester monomers are preferably used in the acrylic binder resin composition in the range of 60 to 95% by weight.

The (meth) acrylic acid ester polymer may be methyl acrylate, ethyl acrylate,
N-butyl acrylate, isobutyl acrylate, t-butyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, t-butyl methacrylate, Examples thereof include 2-ethylhexyl methacrylate and lauryl methacrylate, which are homopolymers or copolymers. Preferably, a polymer of methyl methacrylate or methyl methacrylate and methyl acrylate, ethyl acrylate, butyl acrylate, isobutyl acrylate, 2-ethylhexyl acrylate, n-butyl methacrylate, 2-ethylhexyl methacrylate,
It is a copolymer with lauryl methacrylate. These (meth) acrylic acid ester polymers are preferably used in the acrylic binder resin composition in an amount of 15 to 40% by weight.

As the polyfunctional (meth) acrylic acid ester monomer, ethylene glycol di (meth) is used.
Alkanediol di (meth) acrylates such as acrylate, 1,2-propylene glycol di (meth) acrylate, 1,3-butylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, diethylene glycol di ( (Meth) acrylate, dipropylene glycol di (meth) acrylate,
Polyoxyalkylene glycol di (meth) acrylate such as triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, divinylbenzene, diallyl phthalate, triallyl cyanurate, triallyl Isocyanurate, allyl (meta)
Examples thereof include acrylate, diallyl fumarate, trimethylolpropane tri (meth) acrylate, and pentaerythritol tetra (meth) acrylate. These can be used alone or in combination of two or more. These polyfunctional (meth) acrylic acid ester monomers are contained in the acrylic binder resin composition in an amount of 0.1 to 2
It is preferably used in the range of 0% by weight.

For such an acrylic binder resin composition, an appropriate polymerization catalyst is selected and used according to the method of curing the molded product. For example, in the case of the heat curing method, bis (4-tert-butylcyclohexyl) peroxydicarbonate, lauroyl peroxide, benzoperoxide, 2,2′-azobis-2,4-dimethylvaleronitrile, 2,2 Polymerization catalysts such as'-azobis- (2-amidinopropane) dihydrochloride, 2,2'-azobisisobutyronitrile, organic peroxides such as benzoyl peroxide and mercaptan compounds, azoisobutyronitrile, etc. A catalyst system in combination with the above chain transfer agent is used. Further, in the case of the room temperature or low temperature curing method, a catalyst system composed of benzoyl peroxide and dimethylpatatothiidine, a catalyst system composed of methyl ethyl ketone peroxide and cobalt naphthenate, a water-soluble organic peroxide such as hemiperester maleate. And a metal oxide, hydroxide, carbonate, a basic compound such as an organic acid salt, a catalyst system, methyl ethyl ketone peroxide,
A catalyst system composed of an organic peroxide such as methyl isobutyl ketone peroxide and cycloisane peroxide and a quaternary ammonium salt is used. These polymerization catalysts are preferably used in the acrylic binder resin composition in the range of 0.1 to 5% by weight.

[0019]

EXAMPLES The present invention will be specifically described below with reference to examples. Example 1 68 parts by weight of methyl methacrylate, 5 parts by weight of trimethylolpropane trimethacrylate, 26 parts by weight of a copolymer of methyl methacrylate and butyl acrylate, and 2,
An acrylic binder resin composition consisting of 1 part by weight of 2-azobis-2,4-dimethylvaleronitrile was prepared. On the other hand, an artificial marble piece consisting of 37% by weight of methyl methacrylate-based polymer containing methyl methacrylate as a main component and 63% by weight of aluminum hydroxide powder was pulverized with a roll crusher into 150 mesh or less to obtain artificial marble powder. .

A mixture of 80% by weight of the artificial marble powder and 20% by weight of the acrylic binder resin composition was mixed with a Henschel mixer at a rotation speed of 50 rpm for 5 minutes to obtain a uniform mixture. The obtained mixture was filled in the cavity of the mold of the hot press machine, and the temperature was adjusted to 10
300 mm x 300 mm x 10 m by heating and pressurizing at 0 ° C, pressure 100 Kg / cm ² , molding cycle 5 minutes, and releasing.
A plate-shaped resin molded product of m was obtained. The resin molded product obtained had a natural stone-like appearance with excellent design and had sufficient mechanical strength.

Example 2 36.9% by weight of acrylic polymerizable syrup consisting of 20% by weight of polymethylmethacrylate and 80% by weight of methylmethacrylate, artificial marble powder 6 used in Example 1
2.3 wt% and 2,2-azobis-2,4-dimethylvaleronitrile 0.8 wt% were mixed and vacuum degassed.
The obtained mixture was filled in the cavity of the mold of the hot press machine, and the temperature was 100 ° C. and the pressure was 100 Kg / cm.
^2. Heat and pressurize for 5 minutes in the molding cycle and release 300
A plate-shaped resin molded product having a size of mm × 300 mm × 10 mm was obtained.
The resin molded product obtained had a natural stone-like appearance with excellent design and had sufficient mechanical strength.

Example 3 36.9% by weight of acrylic polymerizable syrup consisting of 20% by weight of polymethylmethacrylate and 80% by weight of methylmethacrylate, artificial marble powder 6 used in Example 1
2.3% by weight, tertiary butyl peroxymaleic acid 0.15% by weight, ethylene glycol dimethacrylate 0.15% by weight and ethylene glycol dimethylcaptoacetate 0.15% by weight were mixed and vacuum degassed.
The resulting mixture was poured into a mold and pressure was 100 Kg /
It is shaped with cm ² and left at room temperature to cure, 300 mm ×
A 300 mm × 10 mm plate-shaped resin molded product was obtained. The obtained resin molded product had a natural stone-like appearance and sufficient mechanical strength.

Comparative Example 1 A mixture of 90% by weight of artificial marble powder used in Example 1 and 10% by weight of an acrylic binder resin composition was prepared.
A Henschel mixer was used to mix at a rotation speed of 50 rpm for 5 minutes to obtain a uniform mixture. The obtained mixture was filled in the cavity of the mold of the hot press machine, and the temperature was adjusted to 1
300 mm x 300 mm x 10 by heating and pressurizing at 00 ° C, pressure 100 kg / cm ² , molding cycle 5 minutes, and releasing.
A plate-shaped resin molded product of mm was obtained. The obtained resin molded product is
The powder remained on the surface as it was, the artificial marble powder was not completely bound, and it was very brittle.

Comparative Example 2 A mixture of 30% by weight of the artificial marble powder used in Example 1 and 70% by weight of the acrylic binder resin composition was used.
A Henschel mixer was used to mix at a rotation speed of 50 rpm for 5 minutes to obtain a uniform mixture. The obtained mixture was filled in the cavity of the mold of the hot press machine, and the temperature was adjusted to 1
300 mm x 300 mm x 10 by heating and pressurizing at 00 ° C, pressure 100 kg / cm ² , molding cycle 5 minutes, and releasing.
A plate-shaped resin molded product of mm was obtained. The obtained resin molded product is
A sufficient natural stone-like appearance was not obtained, and the design was poor.

[0025]

EFFECT OF THE INVENTION The resin molded product of the present invention has a natural stone-like appearance excellent in designability and sufficient mechanical strength by containing the artificial marble powder and the binder resin composition in a specific ratio. In addition to being able to effectively use the waste material of the artificial marble, it can be used for various purposes such as tiles and vases, and can be easily manufactured by the pressure molding method.

Claims (4)

[Claims] 1. Binder resin composition 15 to 60% by weight
And 40-85% by weight of artificial marble powder. 2. The binder resin composition comprises an acrylic resin as a main component and the artificial marble powder comprises an acrylic resin component 20.
The resin molded product according to claim 1, wherein the resin molded product contains ˜85 wt% and an inorganic filler of 15˜80 wt%. 3. Binder resin composition 15 to 60% by weight
A method for producing a resin molded article, which comprises polymerizing and curing a mixture containing 40 to 85% by weight of artificial marble powder under pressure. 4. The resin molding according to claim 3, wherein the binder resin composition is an acrylic polymerizable syrup composed of a (meth) acrylic polymerizable monomer and a (meth) acrylic polymer. Method of manufacturing goods.