JP2000327813A - Photo-curing sheet material, molded laminate material and reinforcing method using same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photo-curing sheet material which can use a variety of monomers as a reactive diluent and which has a short thickening time and which is excellent in handling properties, photo-curing properties and productivity and which can be cured by ultraviolet ray and visible light, a molded laminate section and a reinforcing method using the same. SOLUTION: A photo-curing sheet material comprises (a) a polymerizable unsaturated polymer which is compatible with polymer (b) or which swells polymer (b), (b) polymethyl methacrylate or a high molecular weight polymer containing methyl methacrylate as a main component, (c) a photo-curing agent and (d) a fiber reinforcement. A molded laminate material is obtained by laminating a thermoplastic resin sheet and this sheet material. A reinforcing method is using the photo-curing sheet material on the surface of a molded article.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a light curable by ultraviolet light and visible light which can use various kinds of monomers as a reactive diluent, has a short thickening time, and has excellent handleability, photocurability and productivity. The present invention relates to a curable sheet material, a laminated molding material, and a reinforcing method using the same.

[0002]

2. Description of the Related Art Conventionally, when an unsaturated polyester resin or the like is used as a sheet-shaped molding material, the resin composition is thickened to form a B-stage. For the B-stage, for example, a metal oxide such as magnesium oxide is used as a thickener, or isocyanate is thickened, a photopolymerization initiator is added to increase the viscosity by partial polymerization, or a thickened by a crystalline polyester. Methods are known.

[0003] Examples of photocurable materials include JP-A-63-186744 and JP-A-3-106942 using magnesium oxide. JP-A-60-123538 and the like are disclosed as sheet-like materials using isocyanates. A method of forming a sheet by photopolymerizing a part by irradiating ultraviolet rays is disclosed in JP-B-58-21927, JP-A-56-1.
No. 39535, Japanese Patent Application Laid-Open No. Sho 57-111322, and the like are disclosed. Methods for thickening with a crystalline polyester are disclosed in JP-A-58-67709 and JP-A-5-1123.

Further, as a specific example of thickening using acrylic resin fine powder, which has been studied in recent years, as a thickening material using acrylic fine powder with an unsaturated polyester resin,
JP-A-5-171022, JP-A-9-95519
JP, JP-A-9-174698, JP-A-9-19-1
No. 74781, JP-A-9-176331, and the like. For acrylic resin, JP-A-5-32720, JP-A-5-171022, JP-A-6-298883, JP-A-6-313
No. 019, JP-A-7-188505, JP-A-8-225705, JP-A-10-67906, JP-A-10-265639, JP-A-10-2
JP-A-79765, JP-A-10-287716 and the like are disclosed. These do not describe the photocurable sheet material. These are used for the purpose of improving moldability, low shrinkage, preventing cracks during molding, improving appearance, thickening stability, kneading properties, and handleability.

[0005]

In the conventional thickening method, for example, a metal oxide hardly dissolves in a polymerizable monomer such as styrene and an acrylic monomer. The resin composition used is turbid and inferior in transparency, so that it is inferior in photocurability as a photocurable material. In addition, the viscosity increase requires an active OH group or a COOH group in the polymer component, and there is a limit that it cannot be used for a resin having no COOH group such as a vinyl ester resin. It has a drawback that control for obtaining a sheet-like material is difficult.

[0006] In the case of isocyanate thickening, although solubility is good, it is difficult to control thickening because it is more susceptible to inhibition of thickening by moisture than metal oxides. Furthermore, if there is residual isocyanate, rash may be caused, and the handleability cannot be said to be good.

[0007] In the case of thickening by photopolymerization, light is sometimes used for final curing, and it is difficult to control the steps of thickening and curing, resulting in poor storage stability.

Further, when the viscosity is increased by using an acrylic resin powder as disclosed in Japanese Patent Application Laid-Open No. Hei 5-171022, turbidity remains because insoluble portions remain, and photocuring occurs because of poor transparency. It has drawbacks such as reduced properties.

It is an object of the present invention to provide a sheet material which can use various kinds of monomers as a reactive diluent, has a short thickening time, and is excellent in handleability and photocurability.

[0010]

Means for Solving the Problems The present inventors have made intensive studies on these problems and as a result have completed the present invention.

That is, the present invention relates to (a) a polymerizable unsaturated monomer which is compatible with the polymer (b) or swells the polymer (b);
Polymethyl methacrylate, or a high molecular weight polymer having methyl methacrylate as a main component, (c) a photocuring agent, and
(d) a photocurable sheet-like material characterized by containing a fiber reinforcement, preferably a high molecular weight polymer (b),
A powder having a weight average molecular weight of 100,000 or more and a polymerizable unsaturated monomer (a) is an acrylic polymerizable monomer. Formula 1 [SP =
The compatibilization parameter (hereinafter abbreviated as SP) calculated by Σ (G) / molecular weight ”is 8.1 to 10.0, and further a (meth) acrylic polymer, an unsaturated polyester,
Vinyl ester, containing at least one radical curable polymer resin (e) selected from urethane acrylate, based on 100 parts by weight of polymerizable unsaturated monomer (a),
The polymer (b) contains 1 to 100 parts by weight, further,
A laminated molding material obtained by laminating a thermoplastic resin sheet and the photocurable sheet material, and a method for providing a reinforcing method characterized by using the photocurable sheet material on the surface of a molded product It is.

Next, the present invention will be described in detail.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The polymerizable unsaturated monomer (a) of the present invention is compatible with the polymer (b) or swells the polymer (b). This property can be obtained when the compatibilization parameter (hereinafter referred to as SP, abbreviated as SP value) of (a) is substantially from 8.1 to 10.0. Compatibilization parameter (SP value)
Is obtained by applying the molar traction constant G in Tables 1 and 2 to <Equation 1>, and calculating the polymerizable monomer (a) alone or
It is a calculated value of a mixture of the polymerizable monomer (a). An example of the calculation of the value is specifically shown below.

<Equation 1> SP = Σ (G) / molecular weight

[0015]

[Table 1] Molar traction constant G

[0016]

[Table 2] G by structure type

<Example of calculating SP value> In the case of methyl methacrylate (MMA): Since SP = Σ (G) / molecular weight, ΣG (MMA) = 148.3 × 2 ((CH3-) × 2) + 126.54 × 1 ((CH2 =)
× 1) + 84.51 × 1 ((> C =) × 1) + 326.58 × 1 ((-COO-) × 1)
= 834.23 Therefore, SP: SP = ΣG (MMA) / molecular weight = 834.23 / 100 = 8.34

In the case of a mixture: SP (MMA) = 8.34 SP (NPGDMA) = 8.18 SP (IBMA) = 7.93 If MMA / NPGDMA / IBMA = 100/50/50, SP (mixture) = 8.34 x (100/200) ) + 8.18 × (50/200) +
7.93 x (50/200) = 8.20

In the present invention, the SP of the polymerizable monomer (a)
It is important that the value be in the range of 8.1 to 10.0.
If it is out of this range, the material cannot be sufficiently thickened.

Examples of the polymerizable monomer (a) include methacrylic acid esters and acrylic acid esters (for example, methyl, ethyl, propyl, n-, iso-, or tert-butyl methacrylate or acrylate), Ethylhexyl, dodecyl, tridecyl or stearyl, as well as those containing aliphatic alcohol groups).

Also, vinyl esters such as vinyl acetate, vinyl pivalate, vinyl neononanoate, vinyl neodecanoate, vinyl laurate, vinyl stearate and vinyl benzoate can be used.

Further, as an α, β-unsaturated diester,
For example, dimethyl maleate, diethyl maleate, dibutyl maleate, dicyclohexyl maleate, and fumarate having similar residues can be used.

Further, vinyl aromatic compounds such as styrene, vinyltoluene, and 4-t-butylstyrene can also be used.

Polyfunctional polymerizable monomers can also be used in combination, for example, ethylene glycol, 1,2- and 1,3-propylene glycol, 1,3- and 1,
Acrylic or methacrylic acid of 4-butanediol, 1,6-hexanediol, neopentyl glycol, trimethylolpropane, pentaerythritol, or OH-terminated polyethers (such as polyethylene glycol, polypropylene glycol or polytetramethylene glycol) And aromatic monomers such as divinylbenzene.

Other suitable compounds include hydroxyalkyl acrylate and / or hydroxyalkyl methacrylate, di- or polyglycidyl ether,
Examples include reaction products of dicarboxylic acids, oligoesters, polyesters, di- or triisocyanates, isocyanate group-functional polyurethane prepolymers, and reaction products of acrylic acid or methacrylic acid with di- or polyglycidyl ether.

Among these polymerizable monomers (a), those having an SP calculated from the molar traction constant G of 8.1 to 10.0 can be used alone. Even for monomers having a value smaller than 8.1 and a monomer having a value larger than 10.0, the sum of the product of the weight fraction of each monomer and SP is 8.8.
Two or more types of polymerizable monomers (a) can be used as a mixture, provided that the condition is 1 to 10.0.

The polymer (b) is obtained as a powder of polymethyl methacrylate or a polymer containing methyl methacrylate as a main component, and preferably has a weight average molecular weight of 100,000 or more, and more preferably 100,000 to 3,000,000. It is. The polymer (b) functions as a thickener by slowly dissolving in the polymerizable monomer (a) in the material of the present invention.

Examples of the acrylate and methacrylate as monomers constituting the polymer (b) include, for example, ethyl (meth) acrylate, n-butyl (meth) acrylate, methyl methacrylate, butyl (meth) acrylate, and n -Propyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-
Decyl methacrylate, isobutyl (meth) acrylate, n-amyl (meth) acrylate, isoamyl (meth) acrylate, n-hexyl (meth) acrylate, n-octyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, and the like. Can be Also,
As diene monomers, butadiene, isoprene,
Conjugated diene compounds such as 1,3-pentadiene, cyclopentadiene and dicyclopentadiene, and non-conjugated diene compounds such as 1,4-hexadiene and ethylidene norbornene can also be used.

The monomers copolymerizable therewith include, for example, aromatic vinyl compounds such as styrene, α-methylstyrene, vinyltoluene, pt-butylstyrene and chlorostyrene, acrylamide, N-methylol Acrylamide, acrylamide-based compounds such as N-butoxymethylacrylamide, methacrylamide,
Examples thereof include methacrylamide compounds such as N-methylol methacrylamide and N-butoxymethyl methacrylamide, and glycidyl acrylate, glycidyl methacrylate, and allyl glycidyl acrylate.

As the polymer (b), a crosslinkable monomer having at least two or more radically polymerizable double bonds together with an acrylate or methacrylate monomer can be used. Specific examples of the crosslinkable monomer include ethylene glycol diacrylate, butylene glycol diacrylate, trimethylolpropane diacrylate, trimethylolpropane triacrylate hexanediol diacrylate, oligoethylene diacrylate, ethylene glycol dimethacrylate,
Di (meth) such as butylene glycol dimethacrylate, trimethylolpropane dimethacrylate, trimethylolpropane trimethacrylate, hexanediol dimethacrylate, and oligoethylene dimethacrylate
Acrylates; aromatic divinyl monomers such as divinylbenzene, triallyl trimellitate, triallyl isocyanurate and the like. The amount of the crosslinkable monomer should not exceed 0.5% by weight in the copolymer. Because the degree of crosslinking is too high, it does not swell in the matrix resin,
This is because reducing the transparency of the sheet also reduces the photocurability.

The method for producing the polymer (b) is not limited, but is usually produced as an emulsion by an emulsion polymerization method. That is, a monomer as a component is subjected to emulsion polymerization using a radical polymerization initiator such as a peroxide initiator or a redox initiator as a polymerization initiator in the presence of an emulsifier to obtain an emulsion. Such emulsion polymerization produces an emulsion containing a particulate polymer having a particle size of preferably 300 to 5000 Å.

The emulsion comprising the copolymer obtained by the emulsion polymerization method is usually spray-dried by a multi-blade type rotating disk type, a disk type rotating disk type, a nozzle type or the like to obtain a powdery polymer (b). Is obtained. For this drying,
Generally, the polymer will agglomerate in units of spray droplets, preferably 2
Agglomerated particles of about 0 to 100 μm are formed. The degree of agglomeration depends on the drying conditions, and a step of pulverizing and loosening after drying may be provided. After the emulsion polymerization, latex particles may be coagulated and separated by a salting out method or a freezing method, and the wet cake prepared by dehydration may be dried in a fluidized bed or the like to obtain aggregated particles.

The amount of the polymer (b) is preferably in the range of 1 to 100 parts by weight based on 100 parts by weight of the monomer (a) or the mixture of the monomers (a). More preferably 10-5
The range is 0 parts by weight. If the amount is less than 1 part by weight, the viscosity will be insufficient, and there will be a problem in handleability such as stickiness.If the amount is more than 100 parts by weight, the viscosity will increase immediately after the addition, making kneading difficult, or This is because, even when kneading is possible, the polymer remains as an insoluble component after thickening, which not only impairs the transparency of the sheet but also lowers the bending strength and impact strength of the molded article after photocuring.

The polymer (b) must not only dissolve or swell in the polymerizable unsaturated monomer (a), but also must not be solidified during and immediately after mixing and stirring. Its thickening rate at 25 ° C.
Should not exceed 1000 poise within a minute. Because, in the step of impregnating the fiber reinforced material (d), which is one of the constituent components, if it exceeds 1000 poise within 10 minutes, the adhesive force at the interface with the fiber reinforced material (d) is lost, and the strength is reduced. Another reason is that the voids remaining at the interface cause the entire body to be clouded and the light transmittance to be greatly reduced, so that the photocurability of the photocurable sheet material of the present invention is greatly delayed.

Further, in addition to the above conditions, the polymer must have a viscosity at 25 ° C. exceeding 1000 poise within 24 hours. Because fiber reinforcement (d)
When the sheet is held in a sheet form after impregnation, the content and unit weight of the fiber reinforcement (d) cannot be controlled, and desired performance cannot be obtained.

The photo-curing agent (c) is a compound which can be decomposed by light having a specific wavelength in the ultraviolet to visible region to generate radicals, such as diacetyl, benzophenone, benzoin, benzyl, benzoin ether, acetophenone,
One or a mixture of organic compounds classified as diethoxyacetophenone, dichlorophenoxyacetophenone, hydroxyl isobutyl ketone, benzyldimethyl ketal, chlorothioxanthone, ethylanthraquinone, benzophenone, thioxanthone, ketal, onium salt, and the like. What mixed the cocatalysts, such as this, is used. The amount added is preferably 0.001 to the total amount of the monomer (a) and the polymer (b).
To 1% by weight, more preferably 0.01 to 0.5% by weight.

As the fiber reinforcing material (d), those usually used as reinforcing (reinforcing) materials may be used. Examples thereof include glass fiber, polyester fiber, phenol fiber, polyvinyl alcohol fiber, aromatic polyamide fiber, nylon fiber,
Carbon fiber. Examples of these forms include chopped strands, chopped strand mats, rovings, and woven fabrics. These fiber reinforcing materials (d) are selected in consideration of the viscosity of the resin composition and the strength of the obtained molded product. The amount of the fiber reinforcing material (d) to be used is preferably 10 to 100 parts by weight based on 100 parts by weight of the total of the monomer (a) and the polymer (b).

In the present invention, it is preferable to add a radical-curable polymer resin (e) in consideration of the physical properties of a molded article. Examples of the polymer resin (e) include unsaturated polyester, vinyl ester resin, urethane (meth) acrylate resin, and (meth) acrylic polymer. These resins (e) are usually compositions containing a polymerizable unsaturated monomer (a), and the mixing ratio thereof is as follows:
Preferably, polymer resin: polymerizable monomer = 30 to 80% by weight: 70 to 20% by weight. The amount of the monomer
It is preferably 0 to 80 parts by weight based on 100 parts by weight of the total of (a) and the polymer powder (b). At this time, the SP value is 8.
It must be in the range of 1 to 10.

The unsaturated polyester of the present invention is preferably obtained by a condensation reaction between a dibasic acid containing an α, β-unsaturated dibasic acid and a polyhydric alcohol, and if necessary, a dicyclopentadiene compound. And a monobasic acid, a monohydric alcohol, a monoepoxy compound and the like can be used as necessary. Preferably number average molecular weight 500 to 5
000.

The vinyl ester resin of the present invention is also called an unsaturated polyester (meth) acrylate resin,
An unsaturated polyester (meth) acrylate obtained by reacting a (meth) acrylic compound at the terminal of the unsaturated polyester.

Further, the vinyl ester resin of the present invention is
An epoxy (meth) acrylate resin, a bisphenol-type epoxy resin alone or a mixture of a bisphenol-type epoxy resin and a novolak-type epoxy resin, is reacted with an unsaturated monobasic acid in the presence of an esterification catalyst. Means what can be obtained.

The urethane (meth) acrylate resin of the present invention is preferably a resin obtained by reacting a polyisocyanate with a polyol such as polyether polyol, polyester polyol or polybutadiene polyol and a hydroxyalkyl (meth) acrylate compound.
For example, a mixture obtained by reacting a polyisocyanate in which polypropylene glycol and tolylene diisocyanate (TDI) are reacted in a molar ratio of 1: 2 and 2-hydroxyethyl methacrylate in a molar ratio of 1: 2 is exemplified.

The composition ratio of the polymerizable unsaturated monomer (a) of the present invention to the polymer (b) is preferably (a) :( b) = 95-1.
0% by weight: 5 to 90% by weight. More preferably 95
５０50% by weight: 5 to 50% by weight. Light curing agent (c)
Is preferably 0.001 to 0.003 to the total amount of these (a) and (b).
1% by weight, the fiber reinforcing material (d) is 1% of these (a) and (b)
It is preferably 10 to 100 parts by weight with respect to 00 parts by weight. The amount of the polymer resin (e) is preferably 0 to 80 parts by weight based on 100 parts by weight of the total of (a) and (b).

When the viscosity of the composition is high, a viscosity reducing agent may be used. The viscosity reducing agent is not particularly limited as long as it can reduce the viscosity of the obtained composition. As such a thickener, specifically, for example, a saturated polyester compound,
BYK (BYK Chemie products, product names W900, W90
5, W960, W965, W980, W990, W99
5, W996, W9010). These thinners may be used alone or in combination of two or more.

The process for producing the photocurable sheet material of the present invention is carried out by adding a polymerizable unsaturated monomer (a) or a monomer mixture (a) having an SP value of preferably 8.1 to 10 at room temperature, for example, to a planetarium. Using a known mixer such as a Lee mixer or a kneader, the photocuring agent (c) is mixed and dissolved. Finally, a compound is produced by adding polymethyl methacrylate or a powdery polymer (b) containing methyl methacrylate as a main component as a thickener and mixing and stirring.

The compound prepared by this mixer is
One or both of the two release films (which may be a light-shielding release film) are applied by a flow coater or a doctor knife to a constant thickness of preferably 0.3 to 5 mm, and preferably fiber reinforced thereon. The material (d) is cut with a chopper and sprayed, or the chopped strand mat is sandwiched between them, and then bonded together with the coated surface inward, preferably rolled by a rolling mill, preferably with a thickness of 0.5 to 7 mm. Obtain a sheet material. If the release film is not light-shielding, a step of storing it in a dark box or covering both sides of the material with a light-shielding film is required. Finally, the material is wound or folded by a roller with both sides covered with a release film. Also, especially SM
When the C machine is not used, for example, a chopped strand mat may be impregnated with the above mixture using a roll or the like.

In the thickening step, the temperature varies depending on the type and amount of the polymer (b) as a thickener.
(5 ° C.) for 1 hour and heating at 45 ° C. for about 30 minutes. The release property of the release film of the obtained photocurable sheet material is good.

The method of using the sheet-like material of the present invention is as follows. The light-shielding film and / or the release film of the material is peeled off outdoors or indoors, and after shaping according to the shape of the object to be coated, If left for about 3 hours, a molded article or an object can be covered. The application of this sheet material is
Examples include a pipe rectifying protection material, a coating material, a lining material, and a fixing material.

Examples of the method of using the sheet material of the present invention include a method for producing a molded product as a laminated molding material with a thermoplastic resin sheet, and a laminated molded product as a reinforcing layer of an existing molded product.

The thermoplastic resin sheet of the present invention includes, for example, polyvinyl chloride, polyethylene, polypropylene and copolymers thereof, acrylic (PMMA and other) resins, AB
It is obtained from S, polystyrene, polycarbonate resin, thermoplastic polyurethane resin, AS (acrylonitrile / styrene copolymer), acryl / vinyl chloride copolymer, etc., and its thickness is preferably 0.1 to 5 mm.

The photocurable sheet material of the present invention is preferably B-staged (prepregged) at a temperature of 80 ° C. or less.
The prepreg-prepared photocurable fiber-reinforced resin sheet material (hereinafter referred to as fiber-reinforced resin sheet material) which is preferably thickened by heating from room temperature to 50 ° C., more preferably at 30 ° C. to 45 ° C. ). In laminating and molding the fiber-reinforced resin sheet material after the thickening, a primer is optionally applied to the back surface of the thermoplastic resin sheet heated to the softening temperature in advance, and then the one-side fixing film is peeled off and exposed. The photocurable fiber-reinforced resin sheet-like material surface of the present invention was pressed and adhered, or, at room temperature, a thermoplastic resin sheet and a fiber-reinforced resin sheet-like material were similarly pressed and adhered to each other to form a laminated molding material of a thermoplastic resin sheet. Heat to the softening temperature, fix this in a vacuum forming mold with the surface of the thermoplastic resin sheet facing the mold surface,
The laminated material is shaped into the shape of the mold surface by suctioning or auxiliaryly pressurizing / pressing from the surface of the fiber reinforced resin sheet material on the back surface of the laminated material. After shaping, irradiate the fiber-reinforced resin sheet-like material surface with ultraviolet light or visible light,
The sheet is cured.

In this case, the light irradiation may be performed while the laminated material is attached to the vacuum forming mold, or may be performed after the laminated material is removed from the mold and the thermoplastic resin is cooled and solidified.
The film left on the back of the fiber reinforced resin sheet material does not hinder light transmission, and if it is a soft thin transparent film,
You can leave it on until this operation is complete.

The pressure is preferably 0.1 to 10
The shaping is performed by a pressure of kg / cm ² . Similarly, when laminating the prepreg-formed sheet material after thickening, a primer may be applied on the back surface of the thermoplastic resin sheet heated to the softening temperature in advance, and then the one-side fixing film is peeled off. The exposed surface of the prepreg-formed fiber-reinforced resin sheet-like material is pressed and adhered, or a laminate obtained by similarly pressing and adhering a thermoplastic resin sheet and a fiber-reinforced resin sheet material at room temperature is subjected to the softening temperature of a thermoplastic resin sheet. After heating, the surface of the thermoplastic resin sheet is fixed to a molding die such as an FRP mold or a metal mold so that the surface of the thermoplastic resin sheet is opposed to the mold surface, and is shaped by heating and compression. After shaping, one side of the mold is removed, and the surface of the mold is irradiated with ultraviolet light or visible light to cure the fiber reinforced resin sheet material. Also in this case, light irradiation may be performed while the laminate is attached to the molding die, or may be performed after the laminate is removed from the mold and the thermoplastic resin sheet is cooled and solidified.

The light irradiation lamp is not particularly limited, but a commercially available high-pressure mercury lamp is preferable.

The photocurable fiber-reinforced resin sheet material of the present invention has a moderate tackiness, and its viscosity decreases when heated.
Flow under low pressure becomes easy. Furthermore, it has flexibility even at room temperature, and has extremely good followability with a thermoplastic resin sheet. The adhesiveness is easy to adhere to the thermoplastic resin sheet and easy to integrate with the thermoplastic resin sheet. In spite of such adhesiveness, when the sheet-like material holding film is peeled off, there is no adhesion of the resin to the film at all, and the workability is excellent and the economical advantage is obtained.

Further, since the sheet-like material is provided in a form sandwiched between films, it is easy to handle such as cutting and stacking before molding, and it is convenient because ultraviolet irradiation is not hindered so much.

The fiber-reinforced resin sheet material can be made of a thermoplastic resin, since various kinds of resins, additives, or types of the fiber reinforcing material (d), or their contents, and the overall thickness can be manufactured. A fiber-reinforced resin sheet material suitable for the thickness, rigidity, feel, etc. of the sheet or the reinforced composite material of the product can be selected. In addition, during the production of the sheet, the degree of thickening can be changed by changing the amount of the polymer (b) added as a thickener, and the tackiness and handleability can be changed.

In order to manufacture a laminated molded product using the sheet material of the present invention as a reinforcing layer of an existing molded product, the fiber-reinforced resin sheet material of the present invention is laminated and pressed on the front surface (back surface) of the molded product. Then, the surface of the fiber-reinforced resin sheet material is irradiated with ultraviolet light or visible light to cure the fiber-reinforced resin sheet material as a reinforcing layer.

The molded product has a movable shape, and is made of a thermoplastic resin or a thermosetting resin (unsaturated polyester resin, epoxy resin, vinyl ester resin, phenol resin, etc.). FRP etc.), metal (for example, rolled steel plate, ED steel plate, stainless steel plate, zinc steel plate, aluminum steel plate, etc.), inorganic material (for example, natural stone material such as concrete, glass, ceramic, marble, etc.), paper, wood products And so on.

[0060]

EXAMPLES The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. Further, “parts” in the text indicates parts by weight.

(Synthesis Example: Synthesis of Polymer Powder) 80 parts of methyl methacrylate were charged into a reactor equipped with a stirrer, 1 part of a polymer emulsifier comprising a methyl methacrylate / methacrylic acid copolymer as an emulsifier, and a catalyst were used. 0.1 part of potassium persulfate was added, and the mixture was stirred at a polymerization temperature of 80 ° C. for 180 minutes in 150 parts by weight of water, and then polymerized until the polymerization conversion reached 98%. The average particle diameter of each of the obtained latexes was in the range of 0.2 to 0.5 μm. The obtained latex was spray-dried at 150 ° C. by spray drying to obtain a polymer powder. Weight average molecular weight is 40
It was 10,000.

(Example 1: Prepreg) A mixture of 100 g of methyl methacrylate having an SP value of 8.3 and 100 g of neopentyl glycol dimethacrylate having an SP value of 8.2 calculated from the molar traction constant was obtained as SP as a mixture.
The value is 8.3. To this, 0.5 g of an ultraviolet curing agent (Irgacure 651, Ciba Specialty Chemicals) is added and stirred and dissolved. Then, the practical synthesis example 1
40 g of the acrylic polymer powder prepared in the above was added and stirred.
This is mixed with 450 g / m ² chopped strand mat 5
Impregnate 0 cm x 30 cm. The thickening compound is
It exhibits a thickening rate of more than 1000 poise in 20 minutes at 25 ° C. The obtained prepreg was covered with a light-shielding film and stored to obtain a sheet material.

The material is a transparent, solid sheet with some tack. Curability was cured only by irradiation with an ultraviolet lamp for 5 seconds.

Example 2 Prepreg: 100 g of methyl methacrylate having an SP value calculated from the molar traction constant of 8.3, 50 g of neopentyl glycol dimethacrylate of 8.2 and isobornyl methacrylate of 7.9 50 g of the mixture has an SP value of 8.18 as a mixture. UV curing agent (Irgacure 651, Ciba Specialty Chemicals)
Add 5 g and dissolve with stirring. Thereafter, 40 g of the acrylic polymer powder prepared in the practical synthesis example is added and stirred. This is 450g / m ² chopped strand mat 50cm
Impregnate × 30 cm. The thickening compound is 25 ° C
Showed a rapidly increasing viscosity exceeding 1000 poise within 20 minutes. The obtained sheet material (prepreg) is covered with a light-shielding film and stored. The obtained sheet material was transparent. The material was cured only by irradiating an ultraviolet lamp for 5 seconds.

(Example 3: Pre-preg) 80 g of styrene
-Containing unsaturated polyester resin (Polylite FR-20)
0: A mixture (SP value) obtained by mixing 200 g of Dainippon Ink and Chemicals, Inc. and 20 g of methyl methacrylate.
8.4) After production, an ultraviolet curing agent (Irgacure 651,
0.5 g of Ciba Specialty Chemicals) and dissolve with stirring. Thereafter, 40 g of the acrylic polymer powder prepared in the practical synthesis example is added and stirred. This is 45
0g / m ² of chopped strand mat 50cm × 30cm
Impregnated. The thickening compound showed a fast thickening of more than 1000 poise within 30 minutes at 25 ° C. The obtained molding material was covered with a light-shielding film and stored.

The prepreg was curable only by irradiating an ultraviolet lamp for 10 seconds.

Example 4 Vinyl Ester Prepreg
A photocurable sheet material was prepared in the same manner as in Example 3, except that a vinyl ester resin synthesized from 1 mol of bisphenol A and 2 mol of methacrylic acid was used instead of the unsaturated polyester resin. The thickening of the compound is 100 poise or less during stirring for 1 minute, and 1000
Poise. The obtained sheet is wrapped in a light-shielding aluminum vapor-deposited film and heated at 40 ° C. for 5 minutes to form a prepreg sheet having good handleability. The obtained sheet material was transparent and was cured by irradiating an ultraviolet lamp for 8 seconds.

Comparative Example 1 Prepreg 200 g of isobornyl methacrylate having an SP value of 7.9 calculated from the molar traction constant was added to an ultraviolet curing agent (Irgacure 65).
1) Add 0.5 g and dissolve with stirring. Thereafter, 40 g of the acrylic polymer powder prepared in the practical synthesis example is added and stirred. This is impregnated into a 450 g / m ² chopped strand mat 50 cm × 30 cm, but the compound is 4 g.
Even at 5 ° C., there was almost no increase in viscosity, and the prepreg could not be used.

(Example 5) The sheet material (prepreg) obtained in Example 3 was overlaid on a polymethyl methacrylate sheet having a thickness of 3 mm, pressed with a roller, and cut into a predetermined area. After heating the laminated material in an air bath at 150 ° C. for 5 minutes, the polymethyl methacrylate surface was placed on the FRP mold so as to face the mold, and suction was performed at a reduced pressure of 30 mmHg from the hole of the mold. . In order to sufficiently shape the laminated material, the mold was covered with an iron lid provided with a hole at the center, and air was pressed at 5 kg / cm ² . After complete shaping, remove the lid, irradiate the sheet-like material (prepreg) surface with a sun lamp SSL250A (manufactured by Stanley Electric) for 20 minutes with the release film attached, and remove the cured laminate from the mold. did. Curing and interlayer adhesion were sufficient.

Example 6 100 parts by weight of a polyester resin (propylene glycol / fumaric acid), 200 parts by weight of calcium carbonate, 2 parts by weight of zinc stearate as an internal release agent, 2 parts by weight of magnesium oxide, and 1 part as a fiber reinforcing material / 2 inch glass fiber, 5 parts by weight, perbutyl O
(Nippon Oil & Fats Co., Ltd. curing agent) Bulk molding compound obtained by thickening a compound consisting of 2 parts by weight was heated and compression molded at 125 ° C. for 10 minutes at 80 kg / cm ² to form a 5 mm thick bathtub. Product was obtained. Dioba-CP-70 as a primer at the bottom and corner of the bathtub
0 (vinyl ester resin, Dainippon Ink and Chemicals)
Was applied, the release film was peeled off only on one side of the sheet-like material (prepreg) obtained in Example 4, and the material was pressed by a roll. Next, the prepreg surface was irradiated with a sun lamp SSL250A (manufactured by Stanley Electric Co., Ltd.) for 20 minutes with the release film attached to one side to obtain a bathtub molded product having a reinforcing layer. Curing and interlayer adhesion were sufficient.

[0071]

The present invention comprises (a), (b), (c), and (d) components, so that various types of monomers can be used as a reactive diluent, the thickening time is short, and the handling is easy. A photocurable sheet material having excellent photocurability and productivity can be obtained. This sheet-like material can be used for the production of laminated molded products and the formation of a backup layer (reinforcement layer) for molded products.
It is a useful material for use as a coating material, a lining material, a fixing material, and the like.

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) C08F 265/06 C08F 265/06 290/06 290/06 C08K 3/00 C08K 3/00 7/04 7/04 C08L 33 / 12 C08L 33/12

Claims (7)

[Claims] (1) A polymer (b) compatible with or a polymer (b)
A polymerizable unsaturated monomer that swells, (b) polymethyl methacrylate, or a high molecular weight polymer having methyl methacrylate as a main component, (c) a photocuring agent, and (d) a fiber reinforcing material. Photo-curable sheet material. 2. The photocurable sheet material according to claim 1, wherein the high molecular weight polymer (b) has a weight average molecular weight of 100,000 or more and is in a powder form. 3. The polymerizable unsaturated monomer (a) is an acrylic polymerizable monomer, and a compatibilization parameter (SP) calculated by the formula “SP = 引 (G) / molecular weight” using a molar traction constant G. 3. The photocurable sheet material according to claim 1, wherein the material is 8.1 to 10.0. 4. The composition according to claim 1, further comprising at least one radical-curable polymer resin (e) selected from (meth) acrylic polymers, unsaturated polyesters, vinyl esters, and urethane acrylates. The photocurable sheet material according to any one of 1 to 3 above. 5. The photocurable composition according to claim 1, wherein the polymer (b) is contained in an amount of 1 to 100 parts by weight based on 100 parts by weight of the polymerizable unsaturated monomer (a). Sheet material. 6. A laminated molding material obtained by laminating a thermoplastic resin sheet and the photocurable sheet material according to claim 1. 7. A reinforcing method comprising using the photocurable sheet material according to claim 1 on the surface of a molded product.