JP6164997B2 - Prepreg sheet, method for producing prepreg sheet, and laminate - Google Patents

Description

  The present invention relates to a prepreg sheet, a method for producing a prepreg sheet, and a laminate.

  Conventionally, a prepreg sheet has been used for repairing, reinforcing, or lining various structural materials such as reinforcing and repairing a member made of fiber reinforced plastic (FRP) and repairing a corroded portion of a steel sheet (see, for example, Patent Document 1). ). When a prepreg sheet is used, for example, a prepreg sheet of a desired size can be bonded to the repair location and then cured by curing, so a curable resin solution (varnish) is applied to the repair location. The repair work is simpler than the case where it is cured by hardening.

JP 2002-88176 A

  However, the conventional prepreg sheet contains many volatile organic compounds (VOC), especially styrene, and there is a possibility that styrene volatilizes and diffuses from the cured product obtained after the work. For this reason, the conventional prepreg sheet cannot be used indoors, and there has been a demand for an improvement that enables indoor construction.

  This invention is made | formed in view of such a situation, Comprising: It aims at providing the prepreg sheet which can prevent volatilization of styrene from the molded object after hardening. Another object of the present invention is to provide a laminate having such a prepreg sheet and a method for producing a prepreg sheet capable of easily producing the prepreg sheet.

In order to solve the above problems, according to one embodiment of the present invention, after impregnating a fiber base material with a liquid composition containing the following (a) to (d), the liquid composition is heat-treated to increase the viscosity: In the following (d), the viscosity when measured under the following measurement conditions is 40000 mPa · s or more, and the lower limit of quantification is 0.005 mg based on Japan Water Works Association Standard JWWA K-149 (2004). A prepreg sheet in which styrene is not detected from the molded product after complete curing in the measurement of / L.
(A) one or more curable resins selected from the group consisting of vinyl ester resins, unsaturated polyester resins, acrylic resins, urethane resins (b) monomers (c) photopolymerization initiators (d) uncrosslinked acrylic resin powders A certain thickening material: 1 mass% or more and 50 mass% or less (measurement conditions) when (a) + (b) + (c) is 100 mass%
90 g of a mixture having the following blends (a1) to (c1) and (d) was heated to 85 ° C. and held at 85 ° C. using a Brookfield B-type viscometer (spindle: No. 7, rotation speed: 100 rpm). Measure viscosity with
(A1) Vinyl ester resin (bisphenol A type vinyl ester resin): 60 g
(B1) Monomer (methacrylic acid ester): 40 g ((a1) + (b1) = 100 g)
(C1) Photopolymerization initiator (2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide): 1 g
(D) Thickener that is an uncrosslinked acrylic resin powder: 10.1 g

  In one embodiment of the present invention, a structure in which light in a wavelength band of 365 nm to 410 nm is absorbed and cured can be used.

One aspect of the present invention includes a step of impregnating a fiber base material containing a liquid composition containing the following (a) to (d) and then heat-treating the liquid composition to increase the viscosity, and the following (d) Provides a method for producing a prepreg sheet having a viscosity of 40,000 mPa · s or more within a retention time of 20 minutes when measured under the following measurement conditions.
(A) one or more curable resins selected from the group consisting of vinyl ester resins, unsaturated polyester resins, acrylic resins, urethane resins (b) monomers (c) photopolymerization initiators (d) uncrosslinked acrylic resin powders A certain thickening material: 1 mass% or more and 50 mass% or less (measurement conditions) when (a) + (b) + (c) is 100 mass%
90 g of a mixture having the following blends (a1) to (c1) and (d) was heated to 85 ° C. and held at 85 ° C. using a Brookfield B type viscometer (spindle: No. 7, rotation speed: 100 rpm). Measure viscosity with
(A1) Vinyl ester resin (bisphenol A type vinyl ester resin): 60 g
(B1) Monomer (methacrylic acid ester): 40 g ((a1) + (b1) = 100 g)
(C1) Photopolymerization initiator (2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide): 1 g
(D) Thickener that is an uncrosslinked acrylic resin powder: 10.1 g

  In one aspect of the present invention, the thickener may be a production method in which the viscosity when measured under the above measurement conditions is 40000 mPa · s or more within 10 minutes of the retention time.

  In one aspect of the present invention, the thickening material may be a production method of a core-shell polymer.

  One embodiment of the present invention provides a laminate including the prepreg sheet or the prepreg sheet manufactured by the method for manufacturing the prepreg sheet, and a pair of protective films covering both surfaces of the prepreg sheet.

  One embodiment of the present invention may be configured such that at least one of the pair of protective films transmits light in a wavelength band that cures the prepreg sheet.

  One embodiment of the present invention may include a light-shielding film that covers a protective film that transmits light in the wavelength band and does not transmit light in the wavelength band, out of the pair of protective films.

  ADVANTAGE OF THE INVENTION According to this invention, the prepreg sheet | seat which can prevent volatilization of styrene from the molded object after hardening can be provided. Moreover, the laminated body which has such a prepreg sheet, and the manufacturing method of the prepreg sheet which can manufacture a prepreg sheet | seat easily can be provided.

It is sectional drawing which shows the prepreg sheet and laminated body of this embodiment. It is process drawing which shows the manufacturing method of the prepreg sheet | seat of this embodiment.

A prepreg sheet according to an embodiment of the present invention is obtained by impregnating a fiber base material with a liquid composition containing the following (a) to (d) and then heat-treating the liquid composition to increase the viscosity. (D) has a viscosity of 40000 mPa · s or more when measured under the following measurement conditions, and the lower limit of quantification is 0.005 mg / L based on Japan Water Works Association Standard JWWA K-149 (2004). In the measurement, styrene is not detected from the molded product after complete curing.
(A) one or more curable resins selected from the group consisting of vinyl ester resins, unsaturated polyester resins, acrylic resins, urethane resins (b) monomers (c) photopolymerization initiators (d) uncrosslinked acrylic resin powders A certain thickening material: 1 mass% or more and 50 mass% or less (measurement conditions) when (a) + (b) + (c) is 100 mass%
90 g of a mixture having the following blends (a1) to (c1) and (d) was heated to 85 ° C. and held at 85 ° C. using a Brookfield B-type viscometer (spindle: No. 7, rotation speed: 100 rpm). Measure viscosity with
(A1) Vinyl ester resin (bisphenol A type vinyl ester resin): 60 g
(B1) Monomer (methacrylic acid ester): 40 g ((a1) + (b1) = 100 g)
(C1) Photopolymerization initiator (2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide): 1 g
(D) Thickener that is an uncrosslinked acrylic resin powder: 10.1 g

  In the above measurement conditions, the amount of “(d) thickening material that is uncrosslinked acrylic resin powder” is an amount that becomes 10% by mass when (a1) + (b1) + (c1) is 100% by mass. It is.

Moreover, the manufacturing method of the prepreg sheet which concerns on one Embodiment of this invention, after impregnating the liquid base material containing the following (a)-(d) in a fiber base material, the said liquid composition is heat-processed and thickened. The following (d) has a viscosity of 40,000 mPa · s or more within a holding time of 20 minutes.
(A) one or more curable resins selected from the group consisting of vinyl ester resins, unsaturated polyester resins, acrylic resins, urethane resins (b) monomers (c) photopolymerization initiators (d) uncrosslinked acrylic resin powders A certain thickening material: 1 mass% or more and 50 mass% or less (measurement conditions) when (a) + (b) + (c) is 100 mass%
90 g of a mixture having the following blends (a1) to (c1) and (d) was heated to 85 ° C. and held at 85 ° C. using a Brookfield B type viscometer (spindle: No. 7, rotation speed: 100 rpm). Measure viscosity with
(A1) Vinyl ester resin (bisphenol A type vinyl ester resin): 60 g
(B1) Monomer (methacrylic acid ester): 40 g ((a1) + (b1) = 100 g)
(C1) Photopolymerization initiator (2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide): 1 g
(D) Thickener that is an uncrosslinked acrylic resin powder: 10.1 g

Moreover, the laminated body which concerns on one Embodiment of this invention has a prepreg sheet manufactured by the manufacturing method of the above-mentioned prepreg sheet or the above-mentioned prepreg sheet, and a pair of protective films which cover both surfaces of the said prepreg sheet. Is.
Hereinafter, it demonstrates in order.

[Prepreg sheet, laminate]
FIG. 1 is a cross-sectional view showing a prepreg sheet and a laminate having a prepreg sheet according to an embodiment of the present invention. As shown in the figure, the laminate 1 includes a prepreg sheet 2 and protective films 3 and 4 that are a pair of protective films covering both surfaces of the prepreg sheet 2.

((A) curable resin)
The prepreg sheet 2 contains a curable resin as a main component. As the curable resin, vinyl ester resin, unsaturated polyester resin, acrylic resin, and urethane resin can be used. These may be used alone or in combination of two or more.

  Examples of the vinyl ester resin include a reaction product of an epoxy resin and an unsaturated monobasic acid such as acrylic acid or methacrylic acid. Examples of the epoxy resin contained in the vinyl ester resin include bisphenol type epoxy resin, phenol novolac type epoxy resin, and cresol novolac type epoxy resin. Examples of the bisphenol type epoxy resin include bisphenol A type, bisphenol AD type, bisphenol S type, and bisphenol F type.

  As an unsaturated polyester resin, the reaction material by the condensation reaction of a polyhydric alcohol and unsaturated polybasic acid (and saturated polybasic acid as needed) can be mentioned, for example.

  The curable resin to be used is preferably one in which the raw material monomer does not contain styrene. The curable resin not using styrene as a raw material does not include unreacted styrene, and styrene is hardly released from the obtained prepreg sheet.

((B) monomer)
The prepreg sheet 2 contains a monomer. The monomer functions as a solvent that dissolves the curable resin (a) and adjusts the viscosity, and also functions as a crosslinking agent that polymerizes and crosslinks the curable resin (a).

  It is preferable that the monomer in this embodiment does not contain styrene. Thereby, it becomes difficult to release styrene from the obtained prepreg sheet.

  As a monomer in this embodiment, 1 or more types chosen from the group which consists of acrylic acid, methacrylic acid, and these ester ((meth) acrylic acid ester) can be used conveniently.

  (Meth) acrylic acid esters include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, and isobutyl (meth) acrylate. And cyclohexyl (meth) acrylate.

  Further, as (meth) acrylic acid esters, hydroxy group-containing monomers such as hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol (meth) Polyfunctional monomers such as acrylate, triethylene glycol di (meth) acrylate, butylene glycol di (meth) acrylate, trimethylolpropane di (meth) acrylate, and trimethylolpropane tri (meth) acrylate can also be used.

  (B) The monomer may be commercially mixed with the (a) curable resin in advance, and even in such a form, the monomer is preferably used as a raw material for the prepreg sheet 2 of the present embodiment. be able to.

  The ratio of (b) monomer to the total amount of (a) curable resin and (b) monomer is preferably 20% by mass or more, and more preferably 30% by mass or more. Moreover, it is preferable that it is 80 mass% or less, and it is more preferable that it is 70 mass% or less. The upper limit value and the lower limit value of the ratio of (b) monomer to (a) curable resin + (b) monomer can be arbitrarily combined.

((C) Photopolymerization initiator)
The prepreg sheet 2 contains a photopolymerization initiator. As the photopolymerization initiator, those capable of generating radicals by light irradiation and initiating radical polymerization are used.

  As a photoinitiator, well-known things, such as an acetophenone series, a benzophenone series, and an acyl phosphine oxide series, can be used, for example. Specifically, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 1-phenyl-2-hydroxy-3-methylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1 -Phenylpropan-1-one etc. can be mentioned. These polymerization initiators may be used alone or in combination of two or more.

  When the photopolymerization initiator is a solution dissolved in a solvent, the solvent preferably does not contain styrene. Thereby, it becomes difficult to release styrene from the obtained prepreg sheet.

  As the photopolymerization initiator, one that has an absorption wavelength band of 365 nm or more and 410 nm or less and that generates light by absorbing light in the wavelength band of this range can be suitably used. Since the light in such a wavelength band is shifted from the ultraviolet absorption region of the curable resin, it is possible to effectively absorb the light energy necessary for the radical generation reaction of the photopolymerization initiator.

  The absorption wavelength band of the photopolymerization initiator may not be included in the wavelength band of 365 nm or more and 410 nm or less. In that case, it is preferable to use a photosensitizer having an absorption wavelength band in a wavelength band of 365 nm or more and 410 nm or less.

((D) thickener)
The prepreg sheet 2 includes a thickener. The thickener is an uncrosslinked acrylic resin powder.

As the thickener in the present embodiment, a material having a viscosity of 40000 mPa · s or more when measured under the following measurement conditions can be suitably used.
(Measurement condition)
90 g of a mixture having the following blends (a1) to (c1) and (d) was heated to 85 ° C. and held at 85 ° C. using a Brookfield B-type viscometer (spindle: No. 7, rotation speed: 100 rpm). Measure viscosity with
(A1) Vinyl ester resin (bisphenol A type vinyl ester resin): 60 g
(B1) Monomer (methacrylic acid ester): 40 g ((a1) + (b1) = 100 g)
(C1) Photopolymerization initiator (2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide): 1 g
(D) Thickener that is an uncrosslinked acrylic resin powder: 10.1 g

  As the methacrylic acid ester used as the “(b1) monomer”, the same methacrylic acid ester exemplified as the “(b) monomer” described above can be used. A polyfunctional monomer can also be used as the methacrylic acid ester.

  The thickening material having a viscosity of less than 40000 mPa · s under the above measurement conditions causes stringing when the protective films 3 and 4 are peeled from the prepreg sheet 2, which causes appearance defects and breakage. On the other hand, the thickening material having a viscosity of 40000 mPa · s or more under the above measurement conditions can suppress the above problems when the prepreg sheet 2 is produced.

  The thickener preferably has an average degree of polymerization of 10,000 or more. The average degree of polymerization of the thickener is preferably 50000 or less.

  If the average polymerization degree of the thickener is less than 10,000, the viscosity when heat-treated and thickened is difficult to increase. Therefore, when the protective films 3 and 4 are peeled from the prepreg sheet 2, stringing occurs, resulting in poor appearance and Cause damage. On the other hand, when the average degree of polymerization of the thickener is 10,000 or more, the viscosity when heat-treated and thickened can be increased to a desired value, and the above problems can be suppressed.

  The thickener used is preferably one that does not contain styrene in the raw material. A thickener that does not use styrene as a raw material does not contain unreacted styrene, and styrene is hardly released from the obtained prepreg sheet. As the thickener, a polymer of acrylic acid or methacrylic acid or an ester thereof can be suitably used. For example, a polymer of methyl methacrylate (MMA) can be suitably used.

  The average degree of polymerization of the thickener can be appropriately adjusted by generally known methods such as polymerization temperature, polymerization time, amount of polymerization initiator, and rate of addition of monomers into the polymerization system.

(Fiber base)
The prepreg sheet 2 has a fiber substrate that is impregnated with the liquid composition containing the above (a) curable resin, (b) monomer, (c) photopolymerization initiator, and (d) a thickener.

  Examples of fibers (constituent fibers) constituting the fiber base material include inorganic fibers such as glass fibers, carbon fibers, and ceramic fibers, and resin fibers such as aramid fibers, acrylic fibers, polyester fibers, polyethylene fibers, and nylon fibers. . Among them, glass fibers that are excellent in terms of light transmittance and strength and are inexpensive can be suitably used. These constituent fibers may be used alone or in combination of two or more.

  The fiber substrate may be a woven fabric (woven fabric), a knitted fabric, or a non-woven fabric. The thing of 0.01 mm or more and 10 mm or less can be used preferably.

  In the prepreg sheet 2 of this embodiment, when the total amount of (a) curable resin and (b) monomer is 100 parts by mass, (c) the content of the photopolymerization initiator is 0.01 parts by mass or more. It is preferable that it is 0.1 mass part or more. Moreover, it is preferable that content of (c) photoinitiator is 5 mass parts or less, and it is more preferable that it is 1 mass part or less. The upper limit value and the lower limit value of the content (parts) of the photopolymerization initiator (c) can be arbitrarily combined.

  Similarly, when the total amount of (a) curable resin, (b) monomer, and (c) photopolymerization initiator is 100 parts by mass, the content of (d) thickener is 1 part by mass or more. Is preferable, and more preferably 5 parts by mass or more. Moreover, it is preferable that content of (d) thickener is 50 mass parts or less, and it is more preferable that it is 30 mass parts or less. The upper limit value and the lower limit value of the content (parts) of the (d) thickener can be arbitrarily combined.

  Moreover, the ratio of the thickened body after thickening the liquid composition containing (a) curable resin, (b) monomer, (c) photopolymerization initiator, and (d) thickener relative to the entire prepreg sheet 2 Can be considered to be the same as the ratio of the liquid composition to the total amount of the liquid composition and the fiber substrate.

  The ratio of the fiber base material to the total amount of the liquid composition and the fiber base material is preferably 3% by mass or more, and more preferably 5% by mass or more. Moreover, it is preferable that it is 80 mass% or less, and it is more preferable that it is 50 mass% or less. The upper limit value and lower limit value of the ratio of the liquid composition to the total amount of the liquid composition and the fiber substrate can be arbitrarily combined.

  The prepreg sheet 2 may contain other components such as pigments and fillers as long as the effects of the present invention are not impaired.

(Protective film)
The protective films 3 and 4 are films that protect the surface of the prepreg sheet 2 during storage of the prepreg sheet 2.

  As the protective films 3 and 4, a polyester film such as a polyethylene terephthalate (PET) film, a nylon film, a vinylon film, a polycarbonate film, a polyethylene film, a polypropylene film, a polyvinyl chloride film, or the like can be used.

  If styrene is not used as a raw material contained in the prepreg sheet 2 or styrene is not contained, even a film made of a resin that swells with styrene can be suitably used as the protective films 3 and 4. .

  The protective films 3 and 4 may have a strip shape extending in one direction, or may be obtained by cutting the strip-shaped protective film into a predetermined size according to the form of the product.

  At least one of the protective films 3 and 4 substantially transmits light in the absorption wavelength band of the photopolymerizable initiator or photosensitizer contained in the prepreg sheet 2 so as to transmit light in the absorption wavelength band. It is preferably transparent. Accordingly, when the prepreg sheet 2 is irradiated with light and cured, at least one of the pair of protective films can remain bonded to the prepreg sheet 2, and repair work using the prepreg sheet 2 is easy. It becomes.

  As described above, when the protective films 3 and 4 are substantially transparent to light in the absorption wavelength band of the photopolymerizable initiator or the photosensitizer, the laminate 1 is a protective film 3 that is transparent. 4 may be further provided so as to have a light shielding film that does not transmit light in the wavelength band. By having such a light shielding film, the prepreg sheet 2 can be shielded from light during storage. Therefore, the prepreg sheet 2 can be stored well without being cured.

[Method for producing prepreg sheet]
FIG. 2 is a process diagram showing the method for producing the prepreg sheet of this embodiment.
First, as shown in FIG. 2A, the above-described liquid composition (represented by reference numeral 21) is applied on the protective film 3.

  Examples of the method for applying the liquid composition 21 onto the protective film 3 include a die coating method, a roller coating method, a spray coating method, a curtain coating method, a slot coating method, a comma coating method, a gravure coating method, a reverse coating method, Examples thereof include a bar coating method and a screen printing method. In FIG. 2A, the liquid composition 21 is illustrated as being applied from the die 100.

  Next, as shown in FIG. 2B, the fiber base material 22 is superimposed on the coating film of the liquid composition 21 applied on the protective film 3, and the fiber base material 22 is impregnated with the liquid composition 21.

  Next, as shown in FIG. 2C, after the protective film 4 is overlaid on the fiber base material 22, the liquid composition 2 is thickened by heat treatment.

  In the present invention, the “heat treatment” is intended to increase the viscosity of the liquid composition 21. The heat treatment may be performed using a heating device such as a heater, or may be performed by irradiating infrared rays. In the figure, it is shown that infrared IR is irradiated.

The temperature of heat processing is 30 degreeC or more and 180 degrees C or less, for example. The temperature of the heat treatment is preferably 40 ° C. or higher, and more preferably 60 ° C. or higher. In addition, the heat treatment temperature is preferably 160 ° C. or lower, and more preferably 140 ° C. or lower. The upper limit value and the lower limit value of these heat treatment temperatures can be arbitrarily combined.
Moreover, the time of heat processing is 60 minutes or less, for example.
The temperature and time of these heat treatments are appropriately set according to the configuration of the manufacturing apparatus used, the product standard of the prepreg sheet 2, and the like.

In the method for producing a prepreg sheet of the present embodiment, the liquid composition 21 includes the above-mentioned (d) thickening material that is an uncrosslinked acrylic resin powder. The thickener has a viscosity of 40000 mPa · s or more within 20 minutes when measured under the following measurement conditions.
(Measurement condition)
90 g of a mixture having the following blends (a1) to (c1) and (d) was heated to 85 ° C. and held at 85 ° C. using a Brookfield B-type viscometer (spindle: No. 7, rotation speed: 100 rpm). Measure viscosity with
(A1) Vinyl ester resin (bisphenol A type vinyl ester resin): 60 g
(B1) Monomer (methacrylic acid ester): 40 g ((a1) + (b1) = 100 g)
(C1) Photopolymerization initiator (2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide): 1 g
(D) Thickener that is an uncrosslinked acrylic resin powder: 10.1 g

  In the above measurement conditions, the thickener having a viscosity of 40,000 mPa · s within 20 minutes of holding time can rapidly increase the viscosity to a desired value during heat treatment, and suppress an increase in manufacturing time. it can. In addition, a thickener having a viscosity of 40,000 mPa · s within 10 minutes under the above measurement conditions is preferable because it can further suppress the production time.

The thickener preferably has an average degree of polymerization of 10,000 to 50,000. When the average polymerization degree of the thickener is 10,000 or more, it can be suitably increased to a desired viscosity during the heat treatment. A thickener whose average degree of polymerization is not included in the above range cannot be increased to a desired viscosity.
Thus, the prepreg sheet 2 of this embodiment can be manufactured.

  The prepreg sheet 2 of the present embodiment thus obtained is molded after being completely cured in a measurement with a lower limit of quantification of 0.005 mg / L based on the Japan Water Works Association Standard JWWA K-149 (2004). Styrene is not detected from the body.

  In the present invention, “completely cured” means that the curable resin and monomer contained in the prepreg sheet 2 are reacted with a photopolymerization initiator at the time of use of the prepreg sheet 2 to polymerize the prepreg sheet 2 in a normal use application. Indicates to cure to a degree.

Specifically, styrene is detected by the following method.
First, a prepreg sheet 2 prepared by impregnating two glass fiber mats of EM450 defined in JIS R3411 with the above liquid composition was impregnated with a light-irradiated molded body, which was 120 mm × Cut to 70 mm and a thickness of 2.3 mm or more to create a test piece. The test piece is used for the test after being held in a constant temperature and humidity chamber at a temperature of 20 ± 1 ° C. and a humidity of 65 ± 5% for 7 days.

  The obtained test piece is placed in a hard glass container (beaker) and then washed with tap water at a flow rate of 5 L / min to 6 L / min for 1 hour. Thereafter, the inside of the beaker is filled with tap water, and after confirming that the test piece is completely immersed in tap water, it is sealed with a polyethylene film and allowed to stand at room temperature (20 ± 15 ° C.) for 24 hours.

On the other hand, the test water used for the dissolution test is prepared as follows.
First, a calcium hydroxide solution is added to purified water so that the calcium hardness is about 30 mg / L, and then the pH is adjusted to 7.5 to 8.0 through carbon dioxide. Take 1/5 to 1/10 of this solution in a separate container, and make a solution with a low pH value through carbon dioxide. The obtained solution having a low pH value is added to the original solution little by little to adjust the pH to 7.0 ± 0.2 to prepare test water.

  Next, the tap water in the beaker is discarded, and the test piece is rinsed once with the test water, and then 2 L of the test water is put into the beaker. Seal with water-washed polyethylene film, leave at 20 ± 1 ° C for 24 hours, protected from light. This immersion water is used as test water.

  At the same time, 2 L of test water is put into a beaker of the same type, sealed with a polyethylene film washed with water, and left in the same place as the test water at 20 ± 1 ° C. for 24 hours with light shielding. The obtained water is used as control water.

  Regarding the obtained test water and control water, “4. Water quality test method” of Annex 1 (normative) “Elution test method of FRP lining material on the inner surface of water tank concrete water tank” of Japan Water Works Association Standard JWWA K-149 (2004) Measured by the method described in “4.11 Styrene” to detect styrene contained in the test water. The lower limit of quantification is 0.005 mg / L.

  The prepreg sheet of this embodiment can be easily used by making it the laminated body 1 by which a pair of protective film was bonded on both surfaces, as shown in FIG. That is, after the laminate 1 is cut to a desired size, one of the protective films is peeled off, the prepreg sheet 2 is bonded to the repaired portion, and the prepreg sheet 2 is irradiated with light and cured. Can be repaired. When the protective film has light transparency, after the prepreg sheet 2 is bonded to the repaired portion, the prepreg sheet 2 can be irradiated with light through the protective film, so that the operation becomes easy. .

  Since the prepreg sheet of this embodiment is one in which styrene is not detected even by the above measurement, it can be used indoors and can be applied indoors.

The prepreg sheet and laminate of this embodiment are configured as described above.
Moreover, the manufacturing method of the prepreg sheet of this embodiment has the above configuration.

  According to the prepreg sheet having the above configuration, it is possible to prevent styrene from volatilizing from the molded body after curing. Moreover, the manufacturing method of such a prepreg sheet and the laminated body which has a prepreg sheet can be provided.

According to the prepreg sheet having the above-described configuration, it is possible to provide a prepreg sheet capable of preventing styrene from volatilizing from the molded body after curing.
Moreover, according to the laminated body of the above structures, the repair work using a prepreg sheet can be performed easily.
Moreover, according to the manufacturing method of the prepreg sheet of the above structure, a prepreg sheet can be manufactured easily.

  The preferred embodiments of the present invention have been described above with reference to the accompanying drawings, but it goes without saying that the present invention is not limited to such examples. Various shapes, combinations, and the like of the constituent members shown in the above-described examples are examples, and various modifications can be made based on design requirements and the like without departing from the gist of the present invention.

[Example]
EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

[1. Confirmation of speed of thickening]
Example 1
100 g of monomer (methacrylic acid ester) solution (60% by mass) of vinyl ester resin (bisphenol A type vinyl ester resin), 1 g of photopolymerization initiator (2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide), Each was weighed and mixed. 10.1 g of thickener 1 (average polymerization degree 20000, acrylic resin, uncrosslinked, core-shell structure) that is 10% by mass when the mixture is 100% by mass with respect to the obtained mixture is added. The mixture was stirred at 300 rpm to 500 rpm for 10 minutes at room temperature using a stirrer (Three-One Motor, manufactured by Shinto Kagaku Co., Ltd.) to obtain a liquid composition.

  90 g of the obtained liquid composition was weighed in a sample bottle, placed in a 85 ° C. hot water bath and heated and held.

  The viscosity of the liquid composition was measured at 85 ° C. using a Brookfield B-type viscometer (digital viscometer DV-II + Pro, Eihiro Seiki Co., Ltd.) at an interval of 1 minute from the start of heating. The measurement conditions were as follows: spindle: no. 7. The rotation speed was 100 rpm.

(Example 2)
The viscosity of the liquid composition was measured in the same manner as in Example 1 except that the thickener 2 (average polymerization degree 30000, acrylic resin, uncrosslinked, core-shell structure) was used.

(Comparative Example 1)
The viscosity of the liquid composition was measured in the same manner as in Example 1 except that the thickener 3 (average polymerization degree 4000, manufactured by Aika Industry Co., Ltd., F-325, uncrosslinked, core-shell structure) was used.

(Comparative Example 2)
The viscosity of the liquid composition was measured in the same manner as in Example 1 except that thickener 4 (average polymerization degree 300000, manufactured by Soken Chemical Industry Co., Ltd., MR-5C, uncrosslinked PMMA) was used.

(Comparative Example 3)
The viscosity of the liquid composition was measured in the same manner as in Example 1 except that the thickener 5 (Soken Chemical Industry Co., Ltd., Chemisnow MX-500, cross-linked acrylic resin) was used.

(Reference Example 1)
The viscosity of the liquid composition was measured in the same manner as in Example 1 except that the thickener 1 was used and styrene was used as the monomer contained in the liquid composition.

(Reference Example 2)
The viscosity of the liquid composition was measured in the same manner as in Example 1 except that the thickener 2 was used and styrene was used as the monomer contained in the liquid composition.

  The results for Examples 1 and 2 are shown in Table 1, and the results for Comparative Examples 1 to 3 and Reference Examples 1 and 2 are shown in Table 2, respectively.

  In the evaluation, on the basis of the viscosity being 40000 mPa · s or more, it was judged that a thickener having a viscosity of 40000 mPa · s or more was usable and a thickener not reaching 40000 mPa · s was unusable.

  As a result of the evaluation, in Examples 1 and 2 using the thickeners 1 and 2, the viscosity of the liquid composition became 40000 mPa · s or more by heat treatment. In a separate confirmation experiment, thickeners 1 and 2 were used to produce a prepreg sheet, which was successfully manufactured without stringing. Therefore, it turned out that the thickeners 1 and 2 can be used as a thickener of this invention.

  In addition, as Reference Examples 1 and 2, when the same thickeners 1 and 2 as in Examples 1 and 2 were used and the liquid composition in which the monomer type was styrene was evaluated, both were more than the corresponding Examples 1 and 2. The viscosity became 40000 mPa · s or more in a short time. For this reason, it was confirmed that the viscosity increase rate was affected when the styrene was not used as the monomer species for the purpose of reducing styrene volatilized from the molded product after the prepreg sheet was completely cured.

  In Examples 1 and 2, the viscosity became 40000 mPa · s or more within 10 minutes of the holding time. Therefore, it was found that the thickeners 1 and 2 can reduce the load on the manufacturing process when applied to the manufacturing method of the present invention.

  On the other hand, it was found that the thickener 3 in Comparative Example 1 was unusable because the viscosity after the heat treatment reached a peak at about 20000 mPa · s and no further increase was observed.

  Moreover, it turned out that the thickener 4 in the comparative example 2 was also unusable since the viscosity after heat processing reached a peak at about 23000 mPa · s and no further increase was observed.

  Further, in Comparative Example 3, the thickener 6 which is a crosslinked polymer was used, but it was found that the viscosity did not increase even when heat treatment was performed, and it was not usable.

(2. Measurement of styrene content)
A liquid composition having the same formulation as in Example 2 was prepared and impregnated into a laminate of two glass fiber mats of EM450 specified in JIS R3411, to prepare a prepreg sheet. The obtained prepreg sheet was light-irradiated and completely molded to obtain a test piece by cutting to 120 mm × 70 mm and a thickness of 2.3 mm. The test piece was used for the test after being held in a constant temperature and humidity chamber at a temperature of 20 ± 1 ° C. and a humidity of 65 ± 5% for 7 days.

  The obtained test piece was placed in a hard glass container (beaker), and then washed with tap water at a flow rate of 5 L / min to 6 L / min for 1 hour. After confirming that the inside of the beaker was filled with tap water, it was sealed with a polyethylene film and allowed to stand at room temperature (20 ± 15 ° C.) for 24 hours.

  On the other hand, after adding a calcium hydroxide solution to purified water so that the calcium hardness is about 30 mg / L, after adjusting the pH to 7.5 to 8.0 through carbon dioxide, 1/5 to 1 of this solution / 10 amount was put in another container, and a solution having a low pH value was obtained through carbon dioxide. The obtained low pH solution was added to the original solution little by little to adjust the pH to 7.0 ± 0.2 to prepare test water.

  Next, the tap water in the beaker was discarded, and the test piece was rinsed once with the test water, and then 2 L of the test water was put into the beaker. It was sealed with a polyethylene film washed with water, allowed to stand at 20 ± 1 ° C. for 24 hours, protected from light. This immersion water was used as test water.

  At the same time, 2 L of test water was put in the same type of beaker, sealed with a polyethylene film washed with water, and shielded from light and left at 20 ± 1 ° C. for 24 hours in the same place as the test water. The obtained water was used as control water.

  Regarding the obtained test water and control water, “4. Water quality test method” of Annex 1 (normative) “Elution test method of FRP lining material on the inner surface of water tank concrete water tank” of Japan Water Works Association Standard JWWA K-149 (2004) The amount of styrene contained in the test water was measured by the method described in “4.11 Styrene”.

  When the amount of styrene was measured for the obtained test water with a lower limit of quantification of 0.005 mg / L, styrene was not detected.

  From the above results, the usefulness of the present invention was confirmed.

  DESCRIPTION OF SYMBOLS 1 ... Laminated body, 2 ... Prepreg sheet | seat, 3, 4 ... Protective film, 21 ... Liquid composition, 22 ... Fiber base material

Claims (8)

After impregnating a fiber base material containing a liquid composition containing the following (a) to (d), the liquid composition is heat treated to increase the viscosity:
In the following (d), the viscosity when measured under the following measurement conditions is 40,000 mPa · s or more within 20 minutes exceeding the retention time of 6 minutes ,
A prepreg sheet in which styrene is not detected from a molded article after complete curing in measurement with a lower limit of quantification of 0.005 mg / L based on Japan Water Works Association Standard JWWA K-149 (2004).
(A) one or more curable resins selected from the group consisting of vinyl ester resins, unsaturated polyester resins, acrylic resins, urethane resins (b) monomers (c) photopolymerization initiators (d) uncrosslinked acrylic resin powders A certain thickening material: 1 mass% or more and 50 mass% or less (measurement conditions) when (a) + (b) + (c) is 100 mass%
90 g of a mixture having the following blends (a1) to (c1) and (d) was heated to 85 ° C. and held at 85 ° C. using a Brookfield B-type viscometer (spindle: No. 7, rotation speed: 100 rpm). Measure viscosity with
(A1) Vinyl ester resin (bisphenol A type vinyl ester resin): 60 g
(B1) Monomer (methacrylic acid ester): 40 g ((a1) + (b1) = 100 g)
(C1) Photopolymerization initiator (2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide): 1 g
(D) Thickener that is an uncrosslinked acrylic resin powder: 10.1 g   The prepreg sheet according to claim 1, wherein the prepreg sheet is cured by absorbing light in a wavelength band of 365 nm or more and 410 nm or less. After impregnating a fiber base material with the liquid composition containing the following (a) to (d), the liquid composition is heat-treated and thickened;
The following (d) is a method for producing a prepreg sheet in which the viscosity when measured under the following measurement conditions exceeds 6 minutes and becomes 40,000 mPa · s or more within 20 minutes.
(A) one or more curable resins selected from the group consisting of vinyl ester resins, unsaturated polyester resins, acrylic resins, urethane resins (b) monomers (c) photopolymerization initiators (d) uncrosslinked acrylic resin powders A certain thickening material: 1 mass% or more and 50 mass% or less (measurement conditions) when (a) + (b) + (c) is 100 mass%
90 g of a mixture having the following blends (a1) to (c1) and (d) was heated to 85 ° C. and held at 85 ° C. using a Brookfield B type viscometer (spindle: No. 7, rotation speed: 100 rpm). Measure viscosity with
(A1) Vinyl ester resin (bisphenol A type vinyl ester resin): 60 g
(B1) Monomer (methacrylic acid ester): 40 g ((a1) + (b1) = 100 g)
(C1) Photopolymerization initiator (2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide): 1 g
(D) Thickener that is an uncrosslinked acrylic resin powder: 10.1 g 4. The method for producing a prepreg sheet according to claim 3, wherein the thickening material has a viscosity when measured under the above measurement conditions, and the retention time exceeds 6 minutes and becomes 40000 mPa · s or more within 10 minutes. 5.   The method for producing a prepreg sheet according to claim 4, wherein the thickening material is a core-shell polymer. And the prepreg sheet according to claim 1 or 2,
And a pair of protective films covering both surfaces of the prepreg sheet.   The laminate according to claim 6, wherein at least one of the pair of protective films transmits light in a wavelength band that cures the prepreg sheet. The laminate according to claim 7, further comprising a light shielding film that covers a protective film that transmits light in the wavelength band of the pair of protective films and does not transmit light in the wavelength band.

Images