JP2015127386A - Tow prepreg, composite material reinforcing pressure container and method of producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tow prepreg that is excellent in storage stability, unwindability from a bobbin, process passability, and a drape property, and can be cured in a short time at low temperature, a composite material reinforcing pressure container with high pressure resistance, and a method of producing the same.SOLUTION: A tow prepreg is obtained by impregnating a reinforced fiber bundle with an epoxy resin composition comprising the following components (A) and (B), with the content of the component (B) being 8-25 pts.mass based on the component (A) 100 pts.mass, wherein the component (A) is an alicyclic epoxy resin component and (B) is a boron trifluoride amine complex.

Description

  The present invention relates to a tow prepreg, a composite material reinforced pressure vessel, and a manufacturing method thereof.

  Because of its light weight, natural gas and hydrogen gas storage tanks mounted on moving bodies such as automobiles have a composite material reinforced pressure vessel (hereinafter referred to as “liner”) reinforced with a fiber reinforced composite material. "Pressure vessel") is used. Examples of the reinforcing fiber used in the fiber reinforced composite material include glass fiber and carbon fiber. Among them, carbon fiber has a high specific strength and can reduce the weight of the pressure vessel. For this reason, carbon fibers are particularly preferably used in the production of hydrogen gas storage tanks that require higher pressure resistance than natural gas storage tanks.

The pressure vessel is generally manufactured by filament winding molding (hereinafter referred to as “FW molding”). The FW molding is a molding method in which a matrix resin composition is supplied and impregnated into a bundle of reinforcing fibers bundled one or more, and wound around a rotating tank liner at a desired tension and angle. In this case, the FW process is continuously performed following the process (impregnation process) of supplying and impregnating the matrix resin composition to the reinforcing fiber bundle.
Further, instead of supplying and impregnating the reinforcing fiber bundle with the matrix resin composition immediately before the FW step, a tow prepreg in which the reinforcing fiber bundle is impregnated with the matrix resin composition in advance can also be used. In this case, the tow prepreg is wound around the rotating tank liner at a desired tension and angle.
Moreover, various advantages can be obtained by using a tow prepreg in FW molding. For example, if a tow prepreg is used, it is not necessary to handle an uncured matrix resin composition in the manufacturing process of the pressure vessel, so that the working environment can be improved. In addition, since there is no impregnation step, the process speed of pressure vessel production can be improved. Moreover, a high-quality and high-performance pressure vessel can be obtained by using a tow prepreg in which the content of the matrix resin composition is controlled.

  As a matrix resin composition used for a fiber reinforced composite material that reinforces a pressure vessel, an epoxy resin composition having high physical properties and good handleability is generally used. The matrix resin composition is required to be impregnated into the reinforcing fiber bundle. In addition, when a tow prepreg is used in FW molding, it is necessary that the tow prepreg has good unwindability, processability, and drapeability from the bobbin (paper tube or the like). Therefore, the epoxy resin composition used for the fiber reinforced composite material that reinforces the pressure vessel needs to have a lower viscosity than the epoxy resin composition used for a general prepreg.

In order to lower the viscosity, acid anhydrides are widely used as curing agents for epoxy resin compositions (see, for example, Patent Documents 1 to 3). An acid anhydride is a low-viscosity liquid curing agent, and can lower the viscosity of the epoxy resin composition.
However, the epoxy resin composition using an acid anhydride has a short pot life, and the storage stability of the tow prepreg is lowered as well as the storage stability of the epoxy resin composition itself. Therefore, it is not suitable for use on an intermediate substrate such as tow prepreg.

An epoxy resin composition using dicyandiamide as a curing agent has also been proposed (see, for example, Patent Document 4). Dicyandiamide is a solid curing agent, and an epoxy resin composition having a longer pot life than when an acid anhydride is used can be obtained.
However, an epoxy resin composition using dicyandiamide tends to have a high viscosity. Therefore, the tow prepreg using the epoxy resin composition is inferior in unwinding from the bobbin, process passability, and drape.

Furthermore, in order to cure the tow prepreg using the general epoxy resin composition described above, it is usually necessary to heat at least about 130 ° C. In recent years, resin liners have begun to be used in place of metal liners for the purpose of further reducing the weight of pressure vessels. As the raw material for the resin liner, polyethylene that is inexpensive and easy to mold is widely used.
However, it was difficult for a polyethylene liner to withstand a high temperature of about 130 ° C. Therefore, a tow prepreg that can be cured at a low temperature is demanded.

JP-A-8-219393 JP 2012-56980 A JP 2012-63015 A JP 2011-157491 A

  The present invention has been made in view of the above circumstances, and has a tow prepreg that is excellent in storage stability, unwinding from a bobbin, process passability, drapeability, can be cured at low temperature in a short time, and has high pressure resistance. It is an object of the present invention to provide a composite material reinforced pressure vessel and a method for manufacturing the same.

The present invention has the following aspects.
[1] An epoxy resin composition containing the following component (A) and component (B) and having a content of component (B) of 8 to 25 parts by mass with respect to 100 parts by mass of component (A) is used as a reinforcing fiber bundle. An impregnated tow prepreg.
Component (A): Alicyclic epoxy resin Component (B): Boron trifluoride amine complex [2] The toe prepreg according to [1], wherein the epoxy resin composition has a viscosity at 30 ° C. of 300 Pa · s or less. .
[3] The tow prepreg according to [1] or [2], wherein the reinforcing fiber bundle is a carbon fiber bundle.

[4] A composite material reinforced pressure vessel manufactured using the tow prepreg according to any one of [1] to [3].
[5] The composite material reinforced pressure vessel according to [4], which is manufactured by winding the tow prepreg around a resin liner.
[6] An epoxy resin composition containing the following component (A) and component (B), wherein the content of the component (B) is 8 to 25 parts by mass with respect to 100 parts by mass of the component (A) in the reinforcing fiber bundle An impregnation step for impregnation, a filament winding step for winding the reinforcing fiber bundle impregnated with the epoxy resin composition around the liner, and a curing for heating the liner around the reinforcing fiber bundle to cure the epoxy resin composition impregnated in the reinforcing fiber bundle The manufacturing method of a composite material reinforcement | strengthening pressure vessel including a process.
Component (A): Alicyclic epoxy resin Component (B): Boron trifluoride amine complex

The tow prepreg of the present invention is excellent in storage stability, unwinding from a bobbin, process passability, and drapeability, and can be cured at a low temperature in a short time.
The composite material reinforced pressure vessel of the present invention has high pressure resistance.
According to the method for producing a composite material reinforced pressure vessel of the present invention, a composite material reinforced pressure vessel having high pressure resistance can be produced at a low temperature in a short time.

It is sectional drawing which shows an example of the composite material reinforcement pressure vessel of this invention.

Hereinafter, the present invention will be described in detail.
In the present invention, “toe prepreg” is a narrow width obtained by impregnating a resin composition into a reinforcing fiber bundle (tow) in which filaments of thousands to tens of thousands of reinforcing fibers are arranged in one direction. It is an intermediate substrate. Usually, it is obtained by impregnating a preheated tow with a resin composition, winding it on a bobbin such as a paper tube after cooling. When in use, the necessary amount is unwound from the bobbin.
In addition, the term “epoxy resin” is used as the name of one category of thermosetting resin and the name of the category of a chemical substance called compound having a plurality of epoxy groups in the molecule. Used in The term “epoxy resin composition” means a composition containing an epoxy resin and a curing agent, and optionally other additives.

"Epoxy resin composition"
The epoxy resin composition used for the tow prepreg of the present invention contains component (A): alicyclic epoxy resin and component (B): boron trifluoride amine complex.
Hereinafter, each component will be described.

<Component (A)>
Component (A) is an alicyclic epoxy resin. By using a component (A), the viscosity of an epoxy resin composition can be made low. Therefore, a tow prepreg excellent in unwinding from the bobbin, process passability, and drape is obtained. Moreover, since the viscosity of an epoxy resin composition can be made low, the handleability of an epoxy resin composition becomes easy and the impregnation property to a reinforcing fiber bundle increases.
In addition, when the component (A) is cured using the component (B) described later, the curing is performed in comparison with the case of curing the epoxy resin (other epoxy resin) other than the component (A) with the component (B). There is an advantage that the reaction starts from a low temperature and ends in a short time.

The alicyclic epoxy resin is a compound in which an epoxy ring is condensed to an aliphatic ring, and preferably a compound having an epoxycyclohexane ring or an epoxycyclopentane ring as a partial structure. As the alicyclic epoxy resin, a compound having an epoxycyclohexane ring as a partial structure is more preferable, and in particular, a compound having two epoxycyclohexane rings in one molecule and bonded by a divalent linking group is particularly preferable. preferable. Moreover, as a component (A), a liquid compound is preferable at normal temperature (about 25 degreeC).
As such a compound, compounds represented by the following structural formulas (1) to (8) are preferable. By using the compound shown by following Structural formula (1)-(8) as a component (A), the viscosity of the epoxy resin composition obtained becomes lower. In addition, the heat resistance of the cured product is improved. Furthermore, when a fiber reinforced composite material is produced, the effect which can adjust appropriately the adhesive strength of an epoxy resin composition and the surface of a reinforced fiber is also acquired.

  Among these, 3 ', 4'-epoxycyclohexanecarboxylate 3,4-epoxycyclohexylmethyl represented by the above structural formula (1) is preferable in terms of excellent balance between handleability and physical properties.

<Component (B)>
Component (B) is a boron trifluoride amine complex. By using the component (B), an epoxy resin composition having a long pot life can be obtained. Therefore, the tow prepreg obtained using the epoxy resin composition is excellent in storage stability. In addition, the fiber reinforced composite material produced using the component (B) as a curing agent has a strength suitable for expressing excellent tensile strength in the adhesive strength between the epoxy resin composition and the surface of the reinforced fiber. Can be obtained.

  The boron trifluoride amine complex is a complex composed of boron trifluoride and an organic amine. Examples of such complexes include boron trifluoride aniline complex, boron trifluoride p-chloroaniline complex, boron trifluoride ethylamine complex, boron trifluoride isopropylamine complex, boron trifluoride benzylamine complex, trifluoride. Examples thereof include boron dimethylamine complex, boron trifluoride diethylamine complex, boron trifluoride dibutylamine complex, boron trifluoride piperidine complex, and boron trifluoride dibenzylamine complex.

  Among these, a boron trifluoride isopropylamine complex is preferable in that the pot life of the obtained epoxy resin composition can be further extended and is easily available industrially. Further, the boron trifluoride isopropylamine complex is excellent in solubility in an epoxy resin. Therefore, if the boron trifluoride isopropylamine complex is used as a curing agent, void generation in the produced fiber-reinforced composite material can be suppressed, and therefore, a more excellent tensile strength expression effect of the fiber-reinforced composite material can be obtained.

  Content of a component (B) is 8 mass parts or more with respect to 100 mass parts of components (A) contained in an epoxy resin composition, Preferably it is 9 mass parts or more. Moreover, an upper limit is 25 mass parts or less, Preferably it is 20 mass parts or less, More preferably, it is 17 mass parts or less. When the content of the component (B) is more than the above upper limit value, the pot life of the epoxy resin composition tends to be short, and when it is less than the above lower limit value, the heat resistance of the cured product tends to be low.

<Optional component>
The epoxy resin component contained in the epoxy resin composition is preferably composed only of the alicyclic epoxy resin as the component (A), but the epoxy resin composition is a component (A) as long as the effects of the present invention are not impaired. Epoxy resins other than A) (other epoxy resins) may be included.
As described above, by reacting component (A) using component (B), it can be cured at a lower temperature and in a shorter time than other epoxy resins. Therefore, the epoxy resin composition containing the component (A) and the component (B) is cured at a low temperature in a short time. On the other hand, other epoxy resins, such as compounds in which an aromatic ring is bonded to a group containing an epoxy group such as a glycidyl group (specifically, a bisphenol A diglycidyl ether type epoxy which is a bifunctional epoxy resin having an aromatic ring) In order to cure resin, bisphenol F diglycidyl ether type epoxy resin, etc.) using component (B), it is necessary to react at a higher temperature. Therefore, it is preferable that an epoxy resin composition does not contain another epoxy resin. When the epoxy resin composition contains another epoxy resin, the upper limit of the content of the other epoxy resin varies depending on the type of the other epoxy resin, but is usually 10 masses per 100 parts by mass of the component (A). The amount is preferably 5 parts by weight or less, more preferably 5 parts by weight or less, and still more preferably 0 parts by weight (that is, no other epoxy resin is contained).

Moreover, it is preferable that the hardening | curing agent contained in an epoxy resin composition consists only of a boron trifluoride amine complex which is a component (B), but if it is a range which does not impair the effect of this invention, except a component (B) The curing agent (other curing agent) may be contained, and a curing accelerator may be used in combination to increase the curing activity.
However, when the component (B) and another curing agent (for example, an amine curing agent, a urea compound, an acid anhydride curing agent) are used in combination, or when the component (B) and a curing accelerator are used in combination, The curing reaction by (B) may be inhibited, and curing at a higher temperature may be required than when the epoxy resin composition contains only the component (B) as a curing agent. Therefore, it is preferable that the component (B) is not used in combination with another curing agent or a curing accelerator, that is, the epoxy resin composition does not contain a curing agent or a curing accelerator other than the component (B).

The epoxy resin composition may contain an additive as long as the effects of the present invention are not impaired.
Additives include rubber particles, silica powder, Aerosil (registered trademark), microballoons, inorganic particles such as antimony trioxide, alumina and titanium oxide, flame retardants such as phosphorus compounds, carbon particles such as carbon black and activated carbon, Examples include foaming agents and wetting agents. These additives are blended in the epoxy resin composition depending on the purpose.
In addition, it is preferable to mix | blend rubber particles with an epoxy resin composition at the point from which the effect of improving the toughness of cured resin is acquired. On the other hand, when rubber particles are added to the epoxy resin composition, the viscosity of the epoxy resin composition tends to increase. Therefore, when considering the impregnation property of the epoxy resin composition into the reinforcing fiber bundle and the possibility of void generation in the composite material layer of the resulting pressure vessel, the epoxy resin composition preferably does not contain rubber particles. .

<Manufacturing method>
The epoxy resin composition used for this invention can be manufactured in accordance with a well-known method, for example, should just manufacture according to the method as described in Unexamined-Japanese-Patent No. 2000-143939, international publication 2011/037239, etc.

<Physical properties>
The viscosity of the epoxy resin composition at 30 ° C. is preferably 300 Pa · s or less, and more preferably 150 Pa · s or less. When the viscosity exceeds 300 Pa · s, it may be difficult to impregnate the handleability and the reinforcing fiber bundle, or when the tow prepreg is used, the unwinding property from the bobbin, the process passability, and the draping property may be reduced. is there. The lower limit of the viscosity is usually about 0.1 Pa · s. If the viscosity is 0.1 Pa · s or more, the epoxy resin composition may fall off when the tow prepreg passes through the process, or after the reinforcing fiber bundle is impregnated with the epoxy resin composition and before the FW process. Can be suppressed. In addition, when a reinforcing fiber bundle (including a tow prepreg) impregnated with an epoxy resin composition is wound around a mandrel or liner by FW molding, dripping of the epoxy resin composition can be suppressed.

  The viscosity at 30 ° C. of the epoxy resin composition was measured using a viscoelasticity measuring device (for example, “AR-G2” manufactured by TA Instruments) using a 34 mmφ parallel plate, a plate gap of 500 μm, a measurement temperature of 30 ° C., It can be measured under measurement conditions of an angular velocity of 10 rad / s and a stress of 300 Pa.

"Toe prepreg"
The tow prepreg of the present invention is obtained by impregnating a reinforcing fiber bundle with the above-described epoxy resin composition, and is obtained by winding it on a bobbin after impregnation.

<Reinforced fiber bundle>
Although it does not restrict | limit especially as a diameter and the number of the filaments which comprise a reinforced fiber bundle, Usually, a diameter is about 3-100 micrometers and a number is about 1000-70000. When the diameter is less than 3 μm, the strength of the filament is small, and when the filament is moved in the lateral direction (direction perpendicular to the longitudinal direction; hereinafter the same), the filament may be cut or fluffed, and if it exceeds 100 μm, it will be hard There is a tendency that the flexibility becomes too low.
Here, the “diameter” is an equivalent area circle equivalent diameter of the cross section of the filament (that is, the diameter of a circle having the same area as the projected area of the cross section of the filament).

As the reinforcing fibers, reinforcing fibers used in ordinary fiber-reinforced composite materials such as glass fibers, carbon fibers, aramid fibers, graphite fibers, and boron fibers can be used. Among these, carbon fibers and graphite fibers having a strand strength of 3500 MPa or more in accordance with JIS R 7601 are preferable, carbon fibers and graphite fibers having a strand strength of 4500 MPa or more are more preferable, and carbon having a strand strength of 5000 MPa or more is more preferable. Fiber.
In addition, when a reinforcing fiber bundle is a carbon fiber bundle, it is preferable that the diameter of a filament is about 3-12 micrometers and a number is about 1000-70000.

<Content of epoxy resin composition>
The content of the epoxy resin composition contained in the tow prepreg is preferably 20% by mass or more and 40% by mass or less. If the content of the epoxy resin composition is 20% by mass or more, the epoxy resin composition can be sufficiently distributed in the reinforcing fiber bundle, and if it is 40% by mass or less, the fiber-containing volume ratio of the fiber-reinforced composite material is Since it becomes high, a mechanical characteristic can be expressed effectively. In order to express the mechanical characteristics more effectively, the content of the epoxy resin composition is more preferably 20% by mass or more and 30% by mass or less.

<Method for producing tow prepreg>
Although the tow prepreg of the present invention can be produced by a known production method, it is preferably produced through the following steps (1) to (6).
Step (1): A reinforcing fiber bundle (tow) wound on a bobbin such as a paper tube is placed on a creel and tension is applied, and then the reinforcing fiber bundle is unwound at a constant speed using a drive roll or the like.
Step (2): The reinforcing fiber bundle unwound from the creel at a constant speed is heated and widened as necessary.
Process (3): The epoxy resin composition heated as needed is supplied to at least one side of the widened reinforcing fiber bundle.
Step (4): The reinforced fiber bundle is uniformly impregnated with the supplied epoxy resin composition.
Step (5): When the epoxy resin composition has a temperature higher than room temperature, the temperature of the reinforcing fiber bundle impregnated with the epoxy resin composition is cooled to about room temperature.
Step (6): After impregnation with the epoxy resin composition, the reinforcing fiber bundle cooled as necessary is wound on a bobbin such as a paper tube.

The reinforcing fiber bundle is preferably widened and has a flat shape. If the reinforcing fiber bundle is widened and has a flat shape, the contact area with the epoxy resin composition becomes wide.
Examples of the method for widening the reinforcing fiber bundle include a method of rubbing with a cylindrical bar; a method of applying vibration; and a method of crushing. Further, when the reinforcing fiber bundle is widened, it is preferably heated, and depending on the type of sizing agent attached to the carbon fiber, it is usually more preferable to heat the reinforcing fiber bundle to about 50 to 150 ° C. Furthermore, preheating of the reinforcing fiber bundle is performed by increasing the temperature of the reinforcing fiber bundle in advance so that the temperature of the resin composition does not decrease when the epoxy resin composition penetrates into the reinforcing fiber bundle after contact with the epoxy resin composition. There is also a meaning to keep. As the heating method, any of contact heating with a heating body, and non-contact heating methods such as infrared heating and atmosphere heating can be used.

  The widening of the reinforcing fiber bundle may be performed inline or offline. For example, a commercially available widened tape-like reinforcing fiber bundle is regarded as a reinforcing fiber bundle widened off-line.

  As a method for supplying the epoxy resin composition to the reinforcing fiber bundle, there are a resin bath method, a rotating roll method, a paper transfer method, JP-A Nos. 09-176346, 2005-335296, and 2006-0663173. Examples of the nozzle dropping method described above include the resin contact and tow movement methods described in JP-A-08-073630, JP-A-09-031219, and JP-A-8-73630.

  Among these, the rotating roll method, the resin contact method, and the tow movement method are preferable as the epoxy resin composition supply method in terms of control of the supply amount of the epoxy resin composition and ease of implementation. In addition, the width of the reinforcing fiber bundle is usually not stable, and the way in which the reinforcing fiber bundle spreads varies. Therefore, as described in JP-A-8-73630, after the reinforcing fiber bundle is widened, it is effective to narrow and stabilize the tow width immediately before or at the time of contact with the epoxy resin composition. As a specific example, there is a method in which a groove having a predetermined width is provided at the resin discharge port portion or at a position just before the resin discharge port, and the reinforcing fiber bundle is caused to travel in the groove to narrow the width of the reinforcing fiber bundle.

  As a method for impregnating the reinforcing fiber bundle with the epoxy resin composition, a known impregnation method can be used. Among them, a method of rubbing against a heating body such as a heating roll or a hot plate; a method of passing through a heating furnace when the reinforcing fiber bundle supplied with the epoxy resin composition runs idle; heating by non-contact heating means such as infrared heating The method is preferred. In order not to lower the temperature of the reinforcing fiber bundle or the epoxy resin composition between the time when the epoxy resin composition is supplied to the reinforcing fiber bundle and the time when the epoxy resin composition is heated by the heating body and between the heating body and the heating body. It is still more preferable to heat with a contact heating means.

Further, in the step of impregnating the reinforcing fiber bundle with the epoxy resin composition, an external force is applied to the reinforcing fiber bundle to move the filaments constituting the reinforcing fiber bundle in the lateral direction and change the relative position between the filaments to change the epoxy resin composition. It is preferable to add a step of increasing the contact chance of the filament. Thereby, the uniform impregnation effect more than the impregnation effect by simple pressurization or a capillary phenomenon can be raised.
Specifically, it is performed by at least one means such as folding the reinforcing fiber bundle, widening the reinforcing fiber bundle, reducing the width of the reinforcing fiber bundle, or twisting the reinforcing fiber bundle. In these means, the folding means and the twisting means tend to narrow the width of the reinforcing fiber bundle in the same manner as the width reducing means. If the means for reducing the width of the reinforcing fiber bundle and the means for expanding the width of the reinforcing fiber bundle are used in combination, the effect of uniform impregnation becomes higher. The twisting may be performed at the time of impregnation with the epoxy resin composition, and when an untwisted state is necessary after the impregnation, the twisting may be performed after the impregnation. Further, if rubbing is applied simultaneously with or immediately after the twisting, the width of the reinforcing fiber bundle tends to increase, and the uniformity of the impregnation becomes higher due to the movement in the thickness direction of the resin.

  In uniform impregnation by moving the filaments in the transverse direction, it is useful for fluff accumulation, roll cleaning, etc. to contact the rubbing fiber bundle with a roll rotating at a peripheral speed less than the running speed of the reinforcing fiber bundle. is there. If rubbed, the reinforcing fiber bundle does not get tangled on the roll surface, and the roll is rubbed by the reinforcing fiber bundle and is rotated so that the surface in contact with the reinforcing fiber bundle is always cleaned, It is also useful for improving the manufacturing environment. However, the peripheral speed of the roll is preferably 50% or more and 99% or less of the traveling speed of the reinforcing fiber bundle, and more preferably 80% or more and 95% or less. When the peripheral speed of the roll is less than ½ of the traveling speed of the reinforcing fiber bundle, the reinforcing fiber bundle may become fluffy due to strong rubbing, and the tow wound around the bobbin or the tow wound around the bobbin Problems may arise when unpacking the prepreg.

  When the reinforcing fiber bundle is uniformly impregnated with the epoxy resin composition, the mechanical properties of the produced fiber reinforced composite material are improved, and the effects of the present invention are sufficiently obtained.

  The reinforcing fiber bundle uniformly impregnated with the epoxy resin composition is cooled to about room temperature by using a known cooling means such as rubbing against a cooling body or a non-contact cooling means before the bobbin winding process. It is preferable. If it is wound in a state where it is not sufficiently cooled, the epoxy resin composition has a low viscosity, so that slipping may occur during winding and the winding form may be disturbed. In addition, once wound up, heat is difficult to escape from the center, and the high temperature state continues for a relatively long time, so the pot life of the epoxy resin composition is shortened and the storage stability of the tow prepreg is reduced. Sometimes.

<Effect>
The above-described tow prepreg of the present invention is formed by impregnating a reinforcing fiber bundle with the above-described specific epoxy resin composition, so that it has excellent storage stability, unwinding from a bobbin, process passability, drapeability, and low temperature. And can be cured in a short time.
In addition, the tow prepreg of the present invention is suitable for filament winding molding, pultrusion molding, and the like because it has characteristics such as excellent unwinding from the bobbin, process passability, and drapeability.

By the way, as mentioned above, in order to harden the tow prepreg using the conventional general epoxy resin composition, it is necessary to heat at least about 130 ° C. However, when a resin liner (especially a polyethylene liner) is used when producing a composite material reinforced pressure vessel, it is difficult for the resin liner to withstand the curing temperature of the tow prepreg.
However, since the tow prepreg of the present invention can be cured in a short time at a temperature lower than 130 ° C., it can be suitably used for the production of a composite material reinforced pressure vessel using a resin liner such as polyethylene.

  In addition, since the epoxy resin composition used in the present invention and the fiber reinforced composite material produced from the tow prepreg of the present invention are excellent in tensile strength expression, it is suitable not only for composite material reinforced pressure vessels but also for tension material applications, for example. ing.

“Composite reinforced pressure vessel”
A composite material reinforced pressure vessel (hereinafter sometimes simply referred to as a “pressure vessel”) is usually formed by using a resin or metal liner for its inner layer and covering the outer surface of the liner with a composite material layer. ing.
Here, the term “composite material” means a fiber reinforced composite material. In the present invention, the tow prepreg of the present invention is heated (and pressurized if necessary) and cured, and then a cured product obtained by cooling or after impregnating an epoxy resin composition into a reinforcing fiber bundle. It means a cured product obtained by heating (and pressurizing as necessary) without passing through a tow prepreg (that is, without being wound around a bobbin such as a paper tube), and then cooling after curing.
The composite material can be used for general industrial applications such as sporting goods, automobiles, pressure vessels, aircraft, and tendons, but exhibits high performance particularly when used for pressure vessels and tendons. Especially when used as a pressure vessel for hydrogen storage or a moving body such as an automobile, sufficient performance as a pressure vessel can be obtained by reinforcement with a small amount of composite material, so a lighter pressure vessel is obtained. And the best of its strengths.

<Liner>
As the liner used in the pressure vessel of the present invention, a resin liner or a metal liner can be selected and used depending on the application. When the pressure vessel is used as a pressure vessel for hydrogen storage or mounted on a moving body such as an automobile, it is preferable to use a resin liner because the weight can be further reduced.
As the resin liner, a material obtained by shaping a thermoplastic resin such as high-density polyethylene into a container shape by rotational molding or blow molding and a metal base can be used. Since the resin liner has a relatively low heat resistance, it is necessary to suppress the reaction heat generated when the epoxy resin composition is cured. However, since the tow prepreg of the present invention generates little heat during the curing, the liner is made of resin. However, it can be suitably used.
On the other hand, the metal liner is obtained by giving a die shape after shaping a pipe shape or plate shape member made of aluminum alloy or steel into a container shape by spinning or the like.

<Production method of composite material reinforced pressure vessel>
The manufacturing method of the composite material reinforced pressure vessel of the present invention includes an impregnation step of impregnating a reinforcing fiber bundle with the above-described epoxy resin composition, and a filament winding step (FW step) of winding the reinforcing fiber bundle impregnated with the epoxy resin composition around a liner. And a curing step of heating the liner around which the reinforcing fiber bundle is wound to cure the epoxy resin composition impregnated in the reinforcing fiber bundle.

In the method for producing a composite material reinforced pressure vessel of the present invention, a reinforcing fiber bundle impregnated with an epoxy resin composition (hereinafter also referred to as “resin-impregnated reinforcing fiber bundle”) is impregnated between the impregnation step and the FW step. You may have the winding-up process wound up on a bobbin. The resin-impregnated reinforcing fiber bundle wound around the bobbin by the winding process is stored as a tow prepreg until wound around the liner.
When the manufacturing method of the composite material reinforced pressure vessel does not have a winding process, the resin-impregnated reinforcing fiber bundle is wound around the liner without passing through the tow prepreg. On the other hand, when the manufacturing method of the composite material reinforced pressure vessel includes a winding process, the resin-impregnated reinforcing fiber bundle is wound around the liner as a tow prepreg.

(Impregnation process)
The impregnation step is a step of impregnating the reinforcing fiber bundle with the epoxy resin composition.
When the manufacturing method of the composite material reinforced pressure vessel does not include a winding step, the method for supplying the epoxy resin composition to the reinforcing fiber bundle and the impregnation method are not particularly limited, and examples thereof include the following methods. That is, an epoxy resin composition having a certain thickness is applied to a cylindrical drum using a doctor blade, etc., and an epoxy resin composition is supplied by bringing a reinforcing fiber bundle into contact with the epoxy fiber composition. A method of impregnating the composition inside; a method of immersing the reinforcing fiber bundle in a container storing the epoxy resin composition, and then scraping off the unnecessary epoxy resin composition with a bar or a guide; Examples thereof include a method of feeding a resin composition and applying it to a reinforcing fiber bundle. A method of using a drum or a dispenser is preferable in that the excess resin is not supplied to the reinforcing fiber bundle, and the poxy resin composition can be applied to the reinforcing fiber bundle while accurately controlling the impregnation amount to a target value.

  On the other hand, even when the manufacturing method of the composite material reinforced pressure vessel has a winding step, the epoxy resin composition described above as a case of not having a winding step is used as the method for supplying and impregnating the epoxy resin composition to the reinforcing fiber bundle. Examples thereof include a method for supplying the composition and a method for impregnation.

(Winding process)
The winding process is a process of winding the resin-impregnated reinforcing fiber bundle around a bobbin such as a paper tube. The method for winding the resin-impregnated reinforcing fiber bundle around the bobbin is not particularly limited. The resin-impregnated reinforcing fiber bundle wound around the bobbin is stored as a tow prepreg.

(FW process)
The FW process is a process in which a resin-impregnated reinforcing fiber bundle (including a resin-impregnated reinforcing fiber bundle unwound from a tow prepreg) is wound around a liner by a filament winding method.
As described above, in the FW process, the resin-impregnated reinforcing fiber bundle may be wound around the liner without passing through the tow prepreg, or the resin-impregnated reinforcing fiber bundle (toe prepreg) wound around the bobbin such as a paper tube is bobbed. It may be wound around the liner while being pulled out from.

  As a filament winding machine (FW machine) used in the FW process, a conventionally known machine can be used. The FW machine may be capable of winding a single resin-impregnated reinforcing fiber bundle around a core metal or a liner fixed to the core metal, or a plurality of resin-impregnated reinforcing fiber bundles as a core metal or a core metal. It may be one that is simultaneously wound around a fixed liner.

When winding the resin-impregnated reinforcing fiber bundle around the liner, it is preferable to wind the resin-impregnated reinforcing fiber bundle so as to have a layer structure in order to take advantage of the characteristics of the anisotropic material of the resin-impregnated reinforcing fiber bundle. A layer composed of a resin-impregnated reinforcing fiber bundle or a cured layer is referred to as a composite material layer.
In the present invention, the composition and thickness of the composite material layer, and the angle and tension for winding the resin-impregnated reinforcing fiber bundle around the liner can be freely selected depending on the use and shape of the container, the type of contents, and the like.

As a method of winding the resin-impregnated reinforcing fiber bundle, hoop winding and helical winding are known. A layer formed by hoop-wrapping a resin-impregnated reinforcing fiber bundle around a liner is called a “hoop layer”, and a layer formed by helically winding is called a “helical layer”.
For example, in the composite material reinforced pressure vessel 10 shown in FIG. 1, a composite material layer 12 including a hoop layer 12 a and a helical layer 12 b is formed on the outer surface of the liner 11.

(Curing process)
The curing step is a step of heating the liner around which the resin-impregnated reinforcing fiber bundle is wound to cure the epoxy resin composition contained in the resin-impregnated reinforcing fiber bundle.
The curing temperature is determined according to the composition of the epoxy resin composition. The above-described epoxy resin composition used in the present invention can be cured at a temperature lower than that of a conventional epoxy resin composition (specifically, a temperature lower than 130 ° C.). Therefore, the curing temperature can be set to a temperature lower than 130 ° C., and the curing temperature can be endured even if the liner is made of resin.

<Effect>
The composite material reinforced pressure vessel of the present invention has sufficient pressure resistance as a pressure vessel and is lightweight by reinforcement with a small amount of composite material.
The composite material reinforced pressure vessel of the present invention is suitably used as a pressure vessel mounted on a moving body such as a pressure vessel for storing hydrogen or an automobile.
In the method for producing a composite material reinforced pressure vessel of the present invention, the epoxy resin composition can be cured by heating the liner around which the resin-impregnated reinforcing fiber bundle is wound at a temperature lower than 130 ° C. Therefore, according to the method for manufacturing a composite material reinforced pressure vessel of the present invention, a composite material reinforced pressure vessel having high pressure resistance can be manufactured at a low temperature in a short time.

Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited thereto.
The raw material of the epoxy resin composition used in each example is shown below.

"material"
<Component (A)>
2021P: 3,4-epoxycyclohexanecarboxylic acid 3,4-epoxycyclohexylmethyl HTMLCONTROL Forms.HTML: Hidden.1 (Dacel Co., Ltd., “Celoxide 2021P”, bifunctional alicyclic epoxy resin, epoxy equivalent: 137 g / eq)
2081: ε-caprolactone-modified 3 ′, 4′-epoxycyclohexanecarboxylic acid 3,4-epoxycyclohexylmethyl HTMLCONTROL Forms.HTML: Hidden.1 (Daicel Co., Ltd., “Celoxide 2081”, bifunctional alicyclic epoxy resin , Epoxy equivalent: 200 g / eq)
8000: (3,3 ′, 4,4′-diepoxy) bicyclohexyl HTMLCONTROL Forms.HTML: Hidden.1 (manufactured by Daicel Corporation, “Celoxide 8000”, bifunctional alicyclic epoxy resin, epoxy equivalent: 100 g / eq)

<Component (B)>
Anchor 1115: Boron trifluoride isopropylamine complex (manufactured by PTI Japan, "Anchor 1115")

<Epoxy resin other than component (A)>
jER828: bisphenol A type epoxy resin (manufactured by Mitsubishi Chemical Corporation, “jER828”, bifunctional epoxy resin having an aromatic ring, epoxy equivalent: 189 g / eq, 120 P / 25 ° C.)

<Curing agent other than component (B)>
DICY: Dicyandiamide (Mitsubishi Chemical Corporation, “jER Cure DICY7”)
DCMU99: 3, (3,4-dichlorophenyl) -1,1-dimethylurea (Hodogaya Chemical Co., Ltd., “DCMU99”)
XN1045: Tetrahydromethylphthalic anhydride (manufactured by Nagase ChemteX Corporation, “HARDNER XN1045”)

"Example 1"
<Preparation of epoxy resin composition>
Each raw material was weighed in a container according to the composition shown in Table 1, and then stirred and degassed using a stirrer (manufactured by Keyence Corporation, “Hybrid Mixer HM-500”) until the contents were uniform, and then epoxy. A resin composition was prepared.
In addition, the numerical value of each component in Table 1 represents the mass part number of each component mix | blended with an epoxy resin composition.

(Confirmation of curability of epoxy resin composition)
10 g of epoxy resin composition is weighed in an aluminum cup having a diameter of 50 mm and heated in a hot stove (“ETAC HT-310S” manufactured by Enomoto Kasei Co., Ltd.) under the following conditions to determine whether it can be cured at 100 ° C. confirmed. Whether or not curing is possible is determined by measuring the temperature rise DSC of the epoxy resin composition heated under the following conditions. When the total calorific value is 40 J / g or more, “× (cannot be cured)”, and the total calorific value is less than 40 J / g The case of was evaluated as “◯ (curable)”. The results are shown in Table 1.
Temperature rise condition: Temperature rise from room temperature to 2 ° C / min to curing temperature (100 ° C) Curing condition: Hold at 100 ° C for 2 hours Cooling condition: Natural cooling from curing temperature to 50 ° C or less DSC measuring device: Q-1000 ( TA Instruments)
Temperature increase rate: 10 ° C / min

<Production of toe prepreg>
Using the previously prepared epoxy resin composition and high-strength carbon fiber (“37-800”, manufactured by Graphile Co., Ltd., tensile strength: 5520 MPa, tensile elastic modulus: 255 GPa) as a reinforcing fiber, a tow prepreg was prepared as follows. Was made.
The reinforcing fiber bundle (tow) wound around the paper tube was placed on the creel and tension was applied, and then the reinforcing fiber bundle was unwound at a constant speed using a driving roll. The unfolded reinforcing fiber bundle was heated to 50 to 100 ° C. and widened to a width of 11 to 15 mm.
Using the epoxy resin composition supply device so that the content of the epoxy resin composition in the tow prepreg is 24% by mass in the widened reinforcing fiber bundle (hereinafter simply referred to as “reinforcing fiber bundle”), The epoxy resin composition adjusted to 45 ° C. was quantitatively supplied, and the reinforcing fiber bundle was uniformly impregnated with the epoxy resin composition using a resin impregnation apparatus constituted by a heating roll. As one of the impregnation means, a method of moving the above filaments in the lateral direction was adopted so that the reinforcing fiber bundle was uniformly impregnated with the epoxy resin composition.
The reinforcing fiber bundle impregnated with the epoxy resin composition (resin-impregnated reinforcing fiber bundle) was cooled to room temperature and then wound on a bobbin to obtain a tow prepreg.

(Evaluation of storage stability)
The storage stability of the obtained tow prepreg was evaluated using the epoxy resin composition contained in the tow prepreg as follows. When the thickening of the epoxy resin contained in the tow prepreg proceeds, the drapeability of the tow prepreg decreases and the tackiness increases. The lower the viscosity at 30 ° C. of the epoxy resin composition, the better the storage stability of the tow prepreg produced using the epoxy resin composition.
After holding the uncured epoxy resin composition at 23 ° C. and 50% RH for 1 week, the viscosity of the epoxy resin composition at 30 ° C. was confirmed. When the viscosity of the epoxy resin composition at 30 ° C. is more than 300 Pa · s, “× (poor storage stability)”, and when the viscosity is 300 Pa · s or less, “◯ (good storage stability)” It was evaluated. The results are shown in Table 1.
Viscoelasticity measuring device: AR-G2 (manufactured by TA Instruments)
Measurement temperature: 30 ° C
Media: 34mmφ parallel plate Plate gap: 500μm
Stress: 300Pa
Angular velocity: 10 rad / s

<Manufacture of composite material reinforced pressure vessel (pressure vessel)>
As shown in FIG. 1, the tow prepreg obtained previously was wound around an aluminum liner (capacity 9 L) 11 having an outer diameter of 160 mm and a length of 515 mm as shown in FIG. The aluminum liner 11 used was made of a material obtained by heat-treating an aluminum material defined in A6061-T6 of JIS H 4040, and the thickness of the body portion was about 3.3 mm.
The tow prepreg was unwound from the bobbin, adjusted in position via a guide roll, and then wound around the liner 11 as follows.
First, as a first layer in contact with the body portion of the liner 11, a hoop layer 12a having an angle of 88.6 ° with respect to the rotation axis direction of the liner 11 was formed on the body portion so that the thickness thereof was 0.63 mm. Then, the helical layer 12b which reinforces the mirror part of the liner 11 at an angle of 14 ° with respect to the rotation axis direction of the liner 11 was laminated, and wound so that the thickness of the composite material layer 12 of the trunk part was 2.5 mm. The thickness of the composite material layer 12 was determined by measuring the outer diameter with a caliper.
The liner 11 on which the composite material layer 12 is formed by the above procedure is removed from the filament winding apparatus and suspended in the hot air furnace, and the temperature in the furnace is increased at 2 ° C./min until the curing temperature shown in Table 1 is reached. It was. After confirming that the surface temperature of the composite material layer 12 reached the curing temperature, the temperature in the furnace was kept at the curing temperature for 2 hours to cure the epoxy resin composition. Then, the furnace temperature was cooled to 60 ° C. at 1 ° C./min to obtain a pressure vessel (9 L tank).

(Evaluation of unraveling properties)
When unwinding the tow prepreg from the bobbin, the single yarn (filament) of the reinforcing fiber bundle is entangled with the epoxy resin composition on the bobbin, causing problems such as single yarn breakage. "Poor)", and the case where no problem occurred was evaluated as "○ (good unraveling)". The results are shown in Table 1.

(Evaluation of process passability)
When manufacturing a pressure vessel, when the fuzz is confirmed on the tow prepreg surface due to rubbing with a guide roll or the like, “× (poor process passability)” is indicated, and when fuzz is not confirmed, “○ (process pass is indicated) ) ". The results are shown in Table 1.

(Drapability evaluation)
When manufacturing a pressure vessel, if the tow prepreg could not be wound sufficiently along the liner shape, “× (poor draping)”, sufficiently winding the tow prepreg along the liner shape Was evaluated as “◯ (good drape)”. The results are shown in Table 1.

(Measurement of burst pressure)
After setting the pressure vessel in the water pressure breaker and filling the pressure vessel with water, the water pressure was applied to the pressure vessel at a pressure increase rate of 15 MPa / min, and the water pressure when the pressure vessel ruptured was recorded, and the pressure vessel The measured burst pressure was used. The results are shown in Table 1.
As for the hoop stress, it is assumed that there is no resistance to the inner pressure of the liner, that is, the radial stress of the hoop layer in contact with the liner is equal to the inner pressure of the pressure vessel, and the elastic modulus in the circumferential direction of the helical layer is ignored. Assuming that the hoop stress on the outermost surface of the hoop layer is zero, the hoop stress in an arbitrary hoop layer is obtained from the calculation formula for the hoop stress of the thick-walled cylinder shown in equation (i). Can do.
σ = (P × r ₁ ² × (r ₂ ² + r ² )) / (r ² × (r ₂ ² −r ₁ ² )) (i)
[In formula (i), “σ” is the hoop stress (MPa) of the thick cylinder, “P” is the internal pressure (MPa) of the pressure vessel, and “r” is in a cross section perpendicular to the axis of the pressure vessel. Arbitrary radius (mm) from the center, “r ₁ ” is the radius (mm) from the center to the hoop layer in contact with the liner in the cross section perpendicular to the axis of the pressure vessel, and “r ₂ ” is the pressure vessel The radius (mm) from the center in the cross section perpendicular to the axis to the outer wall of the pressure vessel. ]

  Here, the fracture hoop stress of the hoop layer in contact with the liner calculated based on the actual burst pressure (actual measurement value) of the tank having the hoop layer thickness of 0.63 mm measured as described above, and the hoop thickness is 2. The tank internal pressure when the hoop stress of the hoop layer in contact with the 80 mm tank liner is equal is the burst pressure (converted value). The case where the burst pressure (converted value) exceeded 158 MPa obtained by multiplying 70 MPa, which is the specification of the composite material reinforced pressure vessel (9 L tank), by 2.25 times the safety factor, was determined to be acceptable. The results are shown in Table 1.

"Example 2"
<Preparation of epoxy resin composition>
Except for changing the formulation as shown in Table 1, an epoxy resin composition was prepared in the same manner as in Example 1, the curability was confirmed, and the viscosity at 30 ° C was measured. The results are shown in Table 1.

<Manufacture of composite material reinforced pressure vessel (pressure vessel)>
Using the epoxy resin composition prepared above and high-strength carbon fiber (“37-800”, manufactured by Graphile Co., Ltd., tensile strength: 5520 MPa, tensile elastic modulus: 255 GPa) as a reinforcing fiber, a pressure vessel is used as follows. Manufactured.
Supplying and impregnating the epoxy resin composition to the reinforcing fiber unwound from the paper tube using a touch roll so that the content of the epoxy resin composition in the resin-impregnated reinforcing fiber bundle is 24% by mass, and subsequently, Using a filament winding apparatus, it was wound around an aluminum liner as follows. The aluminum liner used was the same as in Example 1.
The reinforcing fiber bundle (resin impregnated reinforcing fiber bundle) supplied and impregnated with the epoxy resin composition during the manufacturing process of the pressure vessel is wound around the liner in the same manner as in Example 1 after adjusting the position via the guide roll. It was. Thereafter, the liner on which the composite material layer was formed was removed from the filament winding apparatus and suspended in the hot air furnace, and the epoxy resin composition was cured in the same manner as in Example 1 to obtain a composite material reinforced pressure vessel (9 L tank). . That is, in this example, a composite material reinforced pressure vessel was manufactured without using a tow prepreg.
The burst pressure was measured in the same manner as in Example 1 using the obtained pressure vessel. The results are shown in Table 1.

"Example 3"
<Preparation of epoxy resin composition>
Except for changing the formulation as shown in Table 1, an epoxy resin composition was prepared in the same manner as in Example 1, the curability was confirmed, and the viscosity at 30 ° C was measured. The results are shown in Table 1.

<Manufacture of composite material reinforced pressure vessel (pressure vessel)>
A composite material reinforced pressure vessel was produced in the same manner as in Example 2 except that the previously prepared epoxy resin composition was used.
The burst pressure was measured in the same manner as in Example 1 using the obtained pressure vessel. The results are shown in Table 1.

Example 4
<Preparation of epoxy resin composition>
Except for changing the formulation as shown in Table 1, an epoxy resin composition was prepared in the same manner as in Example 1, the curability was confirmed, and the viscosity at 30 ° C was measured. The results are shown in Table 1.

<Manufacture of composite material reinforced pressure vessel (pressure vessel)>
A composite material reinforced pressure vessel was produced in the same manner as in Example 2 except that the previously prepared epoxy resin composition was used.
The burst pressure was measured in the same manner as in Example 1 using the obtained pressure vessel. The results are shown in Table 1.

"Comparative Example 1"
<Preparation of epoxy resin composition>
All of the amounts of DICY and DCMU99 shown in Table 1 were uniformly dispersed in a part of the amount of jER828 shown in Table 1 using three rolls. JER828 in which DICY and DCMU99 were dispersed and the remaining jER828 were put into a flask and stirred until the contents became uniform while heating to 40 ° C. to 50 ° C. to prepare an epoxy resin composition.
About the obtained epoxy resin composition, sclerosis | hardenability was confirmed like Example 1, and the viscosity in 30 degreeC was measured. The results are shown in Table 1.

<Production of tow prepreg and production of composite material reinforced pressure vessel (pressure vessel)>
A tow prepreg was produced in the same manner as in Example 1 except that the obtained epoxy resin composition was used. A composite material reinforced pressure vessel (pressure vessel) was produced in the same manner as in Example 1 except that the tow prepreg was used and the curing temperature was changed to 135 ° C.
Using the obtained pressure vessel, the tow prepreg was evaluated for unwinding property, process passing property, and drape property in the same manner as in Example 1, and the burst pressure was measured. The results are shown in Table 1.

"Comparative Example 2"
<Preparation of epoxy resin composition>
Except for changing the formulation as shown in Table 1, an epoxy resin composition was prepared in the same manner as in Example 1, the curability was confirmed, and the viscosity at 30 ° C was measured. The results are shown in Table 1.

<Production of tow prepreg and production of composite material reinforced pressure vessel (pressure vessel)>
A tow prepreg was produced in the same manner as in Example 1 except that the obtained epoxy resin composition was used. A composite material reinforced pressure vessel (pressure vessel) was produced in the same manner as in Example 1 except that the tow prepreg was used and the curing temperature was changed to 150 ° C.
Using the obtained pressure vessel, the tow prepreg was evaluated for unwinding property, process passing property, and drape property in the same manner as in Example 1, and the burst pressure was measured. The results are shown in Table 1.

“Comparative Example 3”
<Preparation of epoxy resin composition>
Except for changing the formulation as shown in Table 1, an epoxy resin composition was prepared in the same manner as in Example 1, the curability was confirmed, and the viscosity at 30 ° C was measured. The results are shown in Table 1.

As is clear from the results in Table 1, the epoxy resin compositions prepared in Examples 1 to 4 could be cured at 100 ° C. Further, the viscosity at 30 ° C. was 300 Pa · s or less, and the storage stability was excellent. In the case of Examples 1 to 4, when producing the composite material reinforced pressure vessel, the epoxy resin composition could be cured at a lower temperature (specifically 110 ° C.) than Comparative Examples 1 and 2. Moreover, the composite material reinforced pressure vessel obtained in each Example had a higher breakdown pressure and higher pressure resistance than the composite material reinforced pressure vessels obtained in Comparative Examples 1 and 2.
Moreover, the tow prepreg obtained in Example 1 was excellent in storage stability, unzipping from the bobbin, process passability, and drapeability.

  The tow prepreg of the present invention can be used for general industrial applications such as sports equipment, automobiles, pressure vessels, aircraft, and tendons. Especially when used for pressure vessels and tendons, it exhibits high performance.

DESCRIPTION OF SYMBOLS 10 Composite material reinforced pressure vessel 11 Liner 12 Composite material layer 12a Hoop layer 12b Helical layer

Claims (6)

A reinforcing fiber bundle is impregnated with an epoxy resin composition containing the following component (A) and component (B), and the content of component (B) is 8 to 25 parts by mass with respect to 100 parts by mass of component (A). Become a tow prepreg.
Component (A): Alicyclic epoxy resin Component (B): Boron trifluoride amine complex   The tow prepreg according to claim 1, wherein the epoxy resin composition has a viscosity at 30 ° C. of 300 Pa · s or less.   The tow prepreg according to claim 1 or 2, wherein the reinforcing fiber bundle is a carbon fiber bundle.   A composite material reinforced pressure vessel manufactured using the tow prepreg according to any one of claims 1 to 3.   The composite material reinforced pressure vessel according to claim 4, which is manufactured by winding the tow prepreg around a resin liner. Impregnation for impregnating reinforcing fiber bundles with an epoxy resin composition containing the following component (A) and component (B), wherein the content of component (B) is 8 to 25 parts by mass with respect to 100 parts by mass of component (A) Process,
A filament winding step of winding a reinforcing fiber bundle impregnated with an epoxy resin composition around a liner;
A method of manufacturing a composite material reinforced pressure vessel, comprising heating a liner around which a reinforcing fiber bundle is wound, and curing an epoxy resin composition impregnated in the reinforcing fiber bundle.
Component (A): Alicyclic epoxy resin Component (B): Boron trifluoride amine complex

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