JPH0732386A - Continuous manufacture of cast molding and continuous casting device - Google Patents

Abstract

PURPOSE:To continuously mold a round rod, a plate, etc., without limiting its length by mixing a raw material for generating polyurethane by two-liquid reaction polymerization and continuously supplying it to a raw material supply unit having a belt for continuously moving molds to form a cylindrical shape and a heater for heating the mold and the belt, and continuously polymerizing it. CONSTITUTION:Isocyanate and mixture of polyhydroxy compound or polyhydroxy compound and chain length extending agent, catalyst are supplied from supply nozzles 1, 2 to a mixer 3, mixed, and supplied from a discharge nozzle 4 to a cast molding section (b). The section (b) has molds 6 having a fixed heater 13, and a cooler 14 at a cast molded form releasing side, and two rotatable endless belts 5 supported by a belt support 8 are, for example, passed through a space between the molds 6 and the cooler 4. At the time of starting, it is preferable to engage a plug 12 with a cast molding outlet. The molds 6 hold the belts 5 in a shape of the molding, and the heater 13 heats a mixture in the belts 5 through the molds 6 to be polymerized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for continuously producing a cast product having a rod (column) body, a hollow tubular body, and a plate body name by utilizing a two-liquid reaction polymerization of urethane. Is.

[0002]

2. Description of the Related Art Polyurethane has been widely applied and developed as a unique industrial material because of its characteristics such as high impact resilience, tough mechanical properties, and excellent wear resistance. Isocyanate, a method for producing polyurethane
A method for producing a cast product by utilizing the polymerization of a two-component reaction of a polyhydroxy compound with a phenolic compound is described in many documents and patents, for example, polyurethane resin (1969, Nikkan Kogyo Shimbun), JP-A-52-125598. Publication, JP-A-5
It is described in JP-A-3-22596 and JP-A-58-188643.

[0003]

However, all of these methods are batch processes and have the drawback of low production efficiency.

Therefore, the object of the present invention is to eliminate the above-mentioned drawbacks, and the present inventors have found that a high production yield can be achieved in the secondary processing and the casting length is not limited. The inventors have found that the product can continuously produce a round bar, a square bar, a pipe, a plate and the like by using a polymerized material for polyurethane, and reached the present invention.

[0005]

Means for Solving the Problems That is, the present invention is as follows: (1) Component A (isocyanate compound) and component B (polyhydroxy compound or a mixture of polyhydroxy compound, chain extender and catalyst) are passed through a mixer. A continuous moving belt having a portion that forms a tubular shape and continuously moves and a mold for maintaining the shape of a cast product, and the mold and the belt are heated by supplying the mixed liquid from a discharge nozzle of a mixer. A continuous heating device having a fixed heater for pouring into a raw material supply part, and continuously polymerizing and casting the components A and B in the casting part of the device, and then cooling the casting product. And (2) a nozzle for supplying components A and B separately to a mixer, and a mixer for mixing the components A and B, and mixing. A and B components in the machine Nozzle for supplying the mixture of the above to a continuous casting device, a continuous moving belt having a portion forming a cylinder and continuously moving, and a mold for maintaining the shape of the cast product, heating the mold and the belt. And a drive unit in which a belt supporting device for moving the continuously moving belt is installed.

The dimensions of the continuous castings produced according to the invention are:
Although not particularly limited, for example, when the cross-sectional shape is circular,
Usually, the diameter is 5 to 500 mmφ, and in the case of a prism, 5 to 500 × 5 to 500 mm square is preferably used. For those with complicated cross-sectional shapes,
It is possible to cast from a size that is the same as the case where the cross-sectional shape is circular. Further, there is no limitation on the length, and it is also possible to cut and arrange the pieces to have an appropriate length, and to cut the pieces to have an arbitrary length.

In the case of a continuous plate, the thickness is 1 to 1
Those having a width of 0 mm and a width of 10 to 500 mm are preferably used.

The cross-sectional shape of the continuous casting product of the present invention is not particularly limited, and various shapes can be easily obtained by changing the shape of the belt. Typical shapes are circle (including oval), triangle, quadrangle,
Examples include polygonal shapes, star shapes, heart shapes, and hollow products thereof.

As the isocyanate compound which is the component A used in the present invention, a generally known compound used in the polyurethane manufacturing industry can be used. A typical example is 2,4-tolylene diisocyanate (TDI-
4), 2,6-tolylene diisocyanate (TDI-
6), 4,4'-diphenylmethane diisocyanate (MDI), 4,4'-diphenylpropane diisocyanate, hexamethylene diisocyanate (HMD)
I), metaxylene diisocyanate (MXDI), lysine diisocyanate (LDI), 1,5-naphthalene diisocyanate (NDI), tolidine diisocyanate.
TODI, paraphenylene diisocyanate (p
-PDI), metaphenylene diisocyanate (m-P
DI), 2-chloro-1,4-phenyldiisocyanate-
(CPDI-2), 1-chloro-2,4-phenyl diisocyanate (CPDI-1), dianisidine diisocyanate, vitrylene diisocyanate and prepolymers of these isocyanate compounds. -And so on.

As the polyhydroxy compound used as the component B in the present invention, a generally known compound used in the polyurethane manufacturing industry can be used. It is roughly classified into so-called polyester polyols such as polyester, poly (oxypropylene ether) polyol, and poly (oxyethylene propylene ether) polyol, acrylic polyol, castor oil derivatives, and -Oil oil derivatives and other hydroxyl group-containing compounds. Typical examples of commonly used polyesters include organic acids such as phthalic acid, adipic acid, dimerized linoleic acid and maleic acid,
Glycols such as ethylene, propylene butylene and diethylene, triols, tetraols, etc., trimethylolpropane, hexanetriol, glycerin, trimethylolethane, pentaerythritol, neopentyl glycol It is a polyester produced from a polyol such as. The polyester having a molecular weight of 300 to 20,000, preferably 500 to 15,000, and the OH value of 10 to 10,000, preferably 20 to 8,000 are suitable. Typical examples of the polyetherpolyol include poly-1,4-oxymethylene glycol, polyoxypropylene glycol, poly (oxypropylene) poly (oxyethylene) glycol and poly (oxybutylene). ) Glycol,
Poly (oxytetramethylene) glycol, poly (oxypropylene) triol, poly (oxypropylene)
Examples thereof include poly (oxyethylene) triol, sorbitol, pentaerythritol, sucrose and starch. Polyetherpolyol has a molecular weight of 100-
The OH number is 10 to 5,000, preferably 20 to 300, preferably in the range of 10,000, preferably 300 to 6000.
A value in the range of 0 is suitable. Further, part or all of the terminal hydroxy groups of these polyhydroxy compounds may be aminated. Further, the above polyhydroxy compounds are used alone or in a mixture of two or more kinds. The mixing ratio of the isocyanate compound / polyol compound is generally 100/70 to 100/140 (weight). The temperatures of the components A and B are usually set to 20 to 100 ° C. A polymerization temperature of 30 to 140 ° C. is generally used.

As the chain length extender of the present invention, any known one can be used. Typical examples are amine compounds such as 1-amino-3,5-diethyl-2,4-diaminobenzene (diethyltoluenediamine), 1-methyl-3,5-diethyl-2,6-diaminobenzene. 1
-Methyl-3,5-diethyl-2,4-diaminobenzene, 1,3,5-triethyl-2,6-diaminobenzene, 3,5,3 ', 5'-tetraethyl-4,4'diaminodiphenylmethane and The derivative is mentioned.
Although an aromatic chain extender is shown here, an aliphatic chain extender is also included in the scope of the present invention. These compounds are used alone or as a mixture of two or more. The amount of the chain extender added is 1 to 50% by weight in the mixture with the polyol compound,
The amount added is preferably 2 to 40% by weight.

As the catalyst of the present invention, a generally known catalyst can be used. For example, amine-based triethylenediamine, N,
N-dimethylcyclohexylmethane, N, N-dimethyl-2-phenylamine, N, N, N ', N'-tetramethylbutanediamine, triethanolamine, methylmorpholine, ethylmorpholine, N-hexamethyltriethylenetetramine, N, N'-dimethylpiperazine and the like are stannous octoate, dibutyltin laurate, red octoate, dibutyltin dilaurate, dibutyltin diacetate, diethyltin diacetate, di-2 in the metallic system. Organotin compounds such as ethylhexyltinoxide, dioctyltin dioxide, stannas oleate are used. These compounds may be used alone or as a mixture of two or more kinds. The amount of the catalyst added is preferably 0.05 to 5 parts by weight with respect to 100 parts by weight of the isocyanate compound, the polyol compound, and the total length of the chain extender.

The method of injecting the component A and the component B into the casting mold of the present invention is not particularly limited, but usually, the solution of both components is injected into the casting mold through a mixer such as a static mixer or an intake mixing. be able to. It is also possible to mix and supply each in the same container.

In the present invention, for component A or B,
A foam can be produced by adding a foaming agent. Known foaming agents can be used, and examples thereof include methylene chloride, nitroalkanes, nitroureas, aldoximes, acid amides, foam compounds, boric acid, N, N-ethyleneurea compounds, 4-membered ring carbonyl compounds, tertiary alcohols, organic blowing agents such as oxalic acid hydrate, CCl ₃ F and CCl ₂ F ₂ , solid carbonic acid,
An inorganic foaming agent such as aluminum borate hydroxide may be used. A foam stabilizer is used as an additive used with the foaming agent. For example, a silicone-based dispersant (RSi [O-
(R ₂ SiO) _n- (oxyalkylene) _m R] ₃ ... In the formula, R is an alkyl group containing 1 to 4 carbon atoms, and n is 4 to
8 is an integer, m is an integer of 20 to 40, oxyalkylene group is derived from propylene oxide and ethylene oxide), paraffin dispersant (liquid paraffin, etc.)
Is usually used. The amount of the foaming agent added is 0.1 to 10% by weight, preferably 0.2 to 5 as the urethane raw material mixture.
A range of weight percent is suitable.

In the present invention, additives such as wax, inorganic filler, thermoplastic resin and thermosetting resin may be added to the cast product produced in the present invention in order to impart various properties. The addition method is not limited, and it is more convenient to add it by mixing or dispersing it with ingredient A or B of the raw material, but supply it to the casting part of the casting device separately from components A and B. You can also Wax is added to improve releasability and slidability, and animal and vegetable waxes, mineral waxes, petroleum waxes (paraffin waxes, microcrystalline waxes, petrolatums), and oxidation and saponification of these as raw materials, Chemical products produced by ester polymerization and other reactions, polyethylene wax, Fischer-Tropsch wax,
Other synthetic waxes and their processed products (for example,
Compounded wax, oxidized wax, hydrogenated wax, etc.). The amount of these waxes added is suitably in the range of 0 to 30% by weight, preferably more than 0 to 25% by weight, as the urethane raw material mixture, and the softening point thereof is 20 ° C to 20 ° C.
A wide range of temperatures at 220 ° C can be used.

In the present invention, a granular, powdery, or fibrous inorganic filler can be added to improve the mechanical properties of the cast product. As the inorganic filler that can be used here, silica, alumina, silica-alumina, talc,
Diatomaceous earth, clay, kaolin, quartz, glass (glass beads, glass balloon, glass fiber, milled fiber-glass, glass roving, glass cloth, glass mat, etc.), mica, gypsum, red iron oxide, graphite,
Titanium dioxide, molybdenum disulfide, zinc oxide, aluminum,
Examples thereof include copper, stainless steel, wollastonite, potassium titanate, manganese oxide, magnesium oxide, calcium carbonate, bentonite, montmorillonite, mica, copper iodide, potassium iodide and mixtures thereof. These inorganic fillers may be used alone,
You may use it as a mixture of 2 or more types. The inorganic filler may be surface-treated with a silane coupling agent. Particularly, aminosilane coupling agents, epoxysilane coupling agents, titanate coupling agents, etc. are effective. It is suitable that the amount of the inorganic filler added is 0 to 90% by weight, preferably more than 0 and 70% by weight as the urethane raw material mixture. The particle size of the granular or powdery form is not particularly specified, but it is generally preferable to be in the range of 0.2 μm to 1000 μm. The fibrous material has a diameter of 1 to 50 μm and a fiber length of 100.
Those having a thickness of μm to 10 mm are preferable.

The granular, powdery, and fibrous thermoplastic resins and thermosetting resins used in the present invention are not particularly limited as long as they have a shape that allows them to be mixed with raw materials. Specific examples include ethylene / acrylic acid copolymers, ethylene / methacrylic acid copolymers, and salts of some or all of the carboxylic acid moieties in these copolymers with sodium, lithium, potassium, zinc, and calcium. Things (ionomer-
Resin), ethylene / methyl acrylate copolymer, ethylene / ethyl acrylate copolymer, ethylene / ethyl acrylate-g-maleic anhydride copolymer (“g” represents graft, the same applies hereinafter), ethylene / Methyl methacrylate-g-maleic anhydride copolymer, ethylene / ethyl acrylate-g-maleimide copolymer, ethylene / ethyl acrylate-g-N-phenylmaleimide copolymer and partially saponified products of these copolymers , Ethylene / propylene copolymer, ethylene / propylene / 1,4-hexadiene copolymer, ethylene / propylene / dicyclopentadiene copolymer, ethylene / propylene / 2,5-norbornadiene copolymer, ethylene / butene copolymer Combined and these α, β-unsaturated carboxylic acids (eg maleic acid, maleic anhydride, Maleic anhydride, fumaric acid, itaconic acid, acrylic acid, methacrylic acid, acrylic acid ester (methyl methacrylic acid ester, glycidyl methacrylic acid ester, etc.), crotonic acid, etc.), maleimide modified copolymer, at least one Vinyl aromatic compounds (styrene, o-methylstyrene, p
-Methylstyrene, α-methylstyrene, 1,3-dimethylstyrene, vinylnaphthalene, etc.) and at least one conjugated diene compound (1,3-butadiene, 2-methyl-1,3-) A block copolymer composed of a polymer block mainly containing butadiene (isoprene), 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 1,3-hexadiene, and the block copolymer thereof Hydrogenated block copolymers thereof, as well as copolymers thereof modified with the above α, β-unsaturated carboxylic acids, polyethylene, polystyrene, polypropylene and heavy polymers modified with these α, β-unsaturated carboxylic acids. Combined, polyvinyl chloride, polyvinylidene chloride, vinyl acetate, polyvinyl acetate resin, polyester resin, poly Enylene ether resin, polyphenylene sulfide resin, polyacetal resin, polycarbonate resin, polyether sulfone, polyallyl sulfone, polybutadiene resin, polyketone resin,
Polyarylate resin, fluororesin, polyoxybenzoyl resin, polyimide resin, polyamide resin, A
BS resin, phenol resin, phenoxy resin, epoxy resin, silicone resin and the like can be mentioned. These resins may be added alone or as a mixture of two or more kinds. It is suitable that the addition amount of these resins is in the range of 0 to 70% by weight, preferably more than 0 and 50% by weight as a urethane raw material mixture. The particle size of granular or powder is not particularly specified, but is generally 0.
2 μm to 1000 μm is preferable, and fibrous ones have a diameter of 1 to 50 μm and a fiber length of 100 μm to 10
0 mm can be used.

In the present invention, those having a shape of continuous fibers (cloth, mat, roving, etc.) of inorganic fibers and / or organic fibers which are difficult to mix or disperse in the raw material components A and B are cast. It is also possible to manufacture a continuous fiber-containing cast product by directly supplying it to the apparatus and casting.

The continuous fibers of inorganic fibers of the present invention (cloth,
As mats, rovings, monofilaments and the like), continuous fibers such as glass fibers, carbon fibers and metal fibers are usually used.

A continuous fiber (cloth, organic fiber) of the present invention
Matte, roving, monofilament, etc.) as cotton fiber, aramid fiber, fluorine fiber, polyamide fiber,
Liquid crystal polyester fibers and other resin fibers can be used.
In order to improve the adhesiveness with these fibers, inorganic fibers that have been surface-treated with a silane coupling agent can also be used. Organic fibers modified with α, β-unsaturated carboxylic acids, epoxy compounds and the like can also be used.

The amount of the inorganic and organic continuous fibers added is 0 to
It is suitable to be in the range of 95% by weight. A fiber having a diameter of 1 μm to 3 mm is particularly preferable in terms of operability and mechanical properties of a cast product.

The method of supplying continuous fibers is not particularly limited. As the cloth and mat, it is also possible to continuously supply a product which has been previously processed into a cast product. It is also possible to supply a large number of rovings while knitting. Low
The bing is added to the casting product by aligning it from the roll so that the predetermined addition amount is obtained. The cloth, mat, and roving are added to the casting product in the casting machine at the start, and then automatically fed into the casting machine by the belt that moves the casting product.

The continuous casting product of the present invention may contain other components as long as it does not impair the polymerizability, such as internal release agents such as metal stearates of magnesium stearate and aluminum stearate, pigments, dyes, etc. Flame retardants, heat resistance agents, antioxidants, weathering agents, lubricants, release agents, antistatic agents, plasticizers, crystal nucleating agents, etc. can be added and introduced.

Next, the present invention will be described with reference to the drawings.

FIG. 1 is a conceptual sectional view of an endless belt type continuous casting apparatus preferably used in the present invention. The continuous casting device comprises a raw material supply part a and a casting part b. 2 is a partial perspective view of the casting portion b on the side of the raw material supply portion a, and FIG. 3 is a view of the casting portion b in FIG. The raw material supply part is a supply nozzle 1 for supplying the component A, a supply nozzle 2 for supplying the component B, a mixer 3 for mixing these, and a discharge nozzle 4 for further supplying the raw material mixed liquid to the casting part. Consists of. The casting part b is a mold 6 having a fixed heater 13 on the raw material supply side, and a cooler 1 having a cooling liquid inlet 15 on the casting product outlet side.
4 and two endlesss which are passed through the hollow portions of the mold 6 and the cooler 14, supported by the belt supporting device 8, and rotatable by the belt driving device 9, the roller 7 and the auxiliary roller 10. It consists of a belt 5. A removable plug 12 can be fitted in the vicinity of the casting product outlet. The stopper is necessary for holding the raw material mixture supplied to the casting device so as not to leak during the start. When the belt is driven and the cast product begins to be continuously taken out, it may be removed at that stage.

FIG. 4 is a conceptual sectional view of the casting device of the endless belt type casting device of FIG. 1 in which an endless belt 17 is used instead of the endless belt 5. Figure 4
The casting apparatus indicated by is also preferably used in the present invention.

Further, in the casting apparatus shown in FIGS. 1 and 4, the mold part may be placed horizontally. The belt may be made of any material as long as it has heat resistance and does not hinder polymerization, and steel, resin, rubber and the like, and combinations thereof may be used.

Further, when the cast product has a small size, for example, a round bar has a diameter of 30 mm or less, and a square or plate-shaped product has one side and a thickness of 30 mm or less, natural cooling is sufficient. For this reason, it is not necessary to install the cooler 14 when a cast product can be obtained without cooling.

The mold is necessary for holding the belt in the shape of the casting when the material of the belt is flexible. Further, the mold may be an integral one or a divided one or more depending on the shape of the belt.
The role of the mold can be replaced by a fixed heater, but changing the shape of the cast product by changing the shape of the mold is more advantageous in terms of economy than changing the shape of the fixed heater. is there.
The fixed heater is necessary to heat the raw material mixture injected into the belt through the mold and the belt to polymerize the raw material mixture to form a cast product. The fixed heater is usually used in pair with the mold. The length of the fixed heater in the casting movement direction is
It cannot be uniquely determined because it depends on the casting operation conditions such as the urethane polymerization rate and the belt take-up rate. Therefore, the fixed heater preferably has a heating zone divided into one or more.

A device for reducing the contact resistance between the belt and the mold, for example, always supplying a lubricant between the belt and the mold, and dividing the mold into a plurality of parts to reduce the contact area. To reduce the contact area by adding a spiral groove to the belt contact portion of the mold to reduce the contact area, to reduce the contact area by providing many vertical grooves in the belt contact portion of the mold, or to reduce the contact area. A device such as a belt movement assist device may be provided. It is also an important point of the present invention to apply a release agent between the belt and the surface of the cast product in order to facilitate the release of the belt and the cast product. The release agent is preferably applied to the inner surface of the belt in advance. For release agent application, except for the belt part inside the casting device,
You can go anywhere

The shape of the continuous casting product of the present invention is not particularly limited, but it may be a columnar product having various cross sections, a hollow product, a plate product or the like. As a specific example, an example thereof is shown in FIGS.
In the case of a hollow casting, it can be obtained by inserting a mandrel in the center. Various shapes of hollow products can be obtained by changing the shape of the mandrel.

The belt used in the present invention traces the shape of the inner wall of the mold by one or a plurality of belts, and plays a role of forming the shape in the casting product. It is necessary to prevent the liquid from leaking. Figure 6
An example of a cross-sectional view showing a joined state of a round bar belt is shown in FIG. 1, but the present invention is not limited to this example. FIG. 6 shows the sectional shape of the belt. The belt must have a broken shape so that the raw material mixture can be supplied.
As the seam, those shown in FIGS.
Here, the belt up to two divisions is shown, but it may be divided into three or more divisions. Further, it is possible to prevent leakage by a method other than the method shown here. Needless to say, it is necessary to consider the shape of the mold for the shape of c or f.

The polyurethane continuous casting product of the present invention obtained as described above can be cut and used as it is, or can be secondary processed to be used for various machine parts and the like.

[0034]

EXAMPLES The present invention will be described in more detail with reference to the following examples. The present invention is not limited to these examples.

Examples 1 and 2 Round bar castings were continuously manufactured under the conditions shown in Table 1.

A belt (made of fiber-reinforced special silicone rubber) at the bottom of the mold is capped, and the raw material is supplied to the heated belt portion of the casting apparatus up to 400 mm above the bottom of the mold, and once. The supply of the raw materials was stopped, and the raw materials in the casting apparatus were polymerized by heating for 5 minutes. Thereafter, the belt was continuously operated downward under the conditions shown in Table 1, and the raw materials were supplied under the conditions shown in Table 1 to continuously produce cast products of round bars.
The cast product had a good surface appearance and had no internal voids.

[0037]

[Table 1]

[0038]

According to the method of the present invention, it is possible to obtain a continuous molded product having various shapes without loss due to molding shrinkage at the time of molding and without internal defects in a high yield.

[Brief description of drawings]

FIG. 1 is a sectional view of a continuous manufacturing apparatus using an endless belt.

FIG. 2 is a partial perspective view of a casting portion B on a raw material supply portion A side.

FIG. 3 is a view of the casting portion of FIG. 1 taken along the line II ′.

FIG. 4 is a cross-sectional view of a continuous manufacturing apparatus using a belt having a constant length.

FIG. 5 is an example of a cross-sectional shape of a continuous molded product.

FIG. 6 is an example of a shape of a joint portion of a belt in a mold.

[Explanation of symbols]

 1 ... Supply nozzle 2 ... Supply nozzle 3 ... Mixer 4 ... Discharge nozzle 5 ... Endless belt 6 ... Mold 7 ... Roller 8 ... Belt support device 9 ... Belt drive device 10 ... Auxiliary roller 11 ... Casting product 12 ... Plug ( 13 ... Heating device 14 ... Cooler 15 ... Coolant outlet 16 ... Coolant inlet 17 ... Ended belt

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Claims (10)

[Claims] 1. Component A (isocyanate compound) and component B
(Polyhydroxy compound or a mixture of polyhydroxy compound and chain extender, catalyst) is fed through a mixer,
A continuous moving belt having a part that continuously moves by forming a cylindrical shape from the discharge nozzle of the mixer, a mold for maintaining the shape of the cast product, and a fixing for heating the mold and the belt. It is injected into a raw material supply section of a continuous casting apparatus having a heater, and the polymerization and casting of the components A and B are continuously carried out in the casting section of the apparatus, and then the casting product is cooled and continuously cast. A continuous production method of cast products, which is characterized in that 2. The continuous production method of a cast product according to claim 1, wherein the component A and / or the component B contains a granular, powdery or fibrous inorganic filler. 3. The component A and / or the component B further contains a granular, powdery, or fibrous thermoplastic resin and / or thermosetting resin.
A method for continuously producing a cast product according to any one of 1. 4. The continuous fiber-containing casting method according to claim 1, further comprising continuously supplying continuous fibers of inorganic fibers and / or organic fibers to a casting device. A continuous production method of cast products, which comprises producing products. 5. The continuous method for producing a cast product according to claim 1, wherein the cast product is a continuous columnar body or a continuous plate-like body. 6. The continuous method for producing a cast product according to claim 1, wherein the cast product is a hollow tubular body. 7. Component A (isocyanate compound), component B
A nozzle for feeding (a mixture of a polyhydroxy compound or a polyhydroxy compound and a chain extender, a catalyst) separately to the mixer and a mixer for mixing the components A and B,
And a discharge nozzle for supplying the mixture of the components A and B in the mixer to a continuous casting device, a continuous moving belt having a cylindrically formed portion and continuously moving, and for maintaining the shape of the casting product. A continuous casting device comprising a mold, a fixed heater for heating the mold and the belt, and a driving device provided with a belt supporting device for moving the continuously moving belt. 8. The continuous casting device according to claim 7, wherein the continuously moving belt is an endless belt. 9. The continuous casting device according to claim 7, wherein the continuous moving belt is an endless belt having a length of 1 m or more and 100 m or less. 10. The continuous casting device according to claim 7, wherein a cooling portion for cooling the cast product is provided on the opposite side of the fixed heater from the raw material supply port side.