The present invention relates to a package in which a plate-shaped composite material is loaded on a mounting board, and a method of manufacturing the package.
In recent years, in the technical field of machinery, so-called plate-shaped fiber-reinforced composite materials containing thermoplastic resins and carbon fibers is noticed (for example, Patent Document 1). For example, in Patent Document 1, the plate-shaped composite materials are excellent in tensile modulus or tensile strength, impact resistance, and the like because fibers are dispersed in the thermoplastic resin, and are considered as a structural member such as an automobile. These plate-shaped composite materials can be press-molded into a target shape by using compression molding or the like, but when a distance from a manufacture position to a press molding position of the composite materials is far, the composite materials need to be conveyed over a long distance.
On the other hand, various packages or holding devices for mounting articles, which are used when various materials such as industrial products and various components are transported, are known in the related art. For example, Patent Document 2 proposes an article mounting device including an article mounting board in which a plurality of fitting holes are formed in advance such that various forms can be mounted on the article mounting board, and an article holding member that is detachably attached on the mounting board and holds articles mounted on the article mounting board.
Patent Document 1: WO 2012/105080
Patent Document 2: JP-A-2002-145268
The shapes of the composite materials to be packed is not only simple shapes such as a square or a rectangle but also a shape that is cut into a target shape in advance according to a shape to be press-molded (hereinafter, the shape of the composite material cut into the target shape may be referred to as a pattern cut shape). When these composite materials each having such a pattern cut shape are packed, it is necessary to prepare holding members and a mounting board for holding the composite materials in accordance with the pattern cut shape, but a large amount of cost and labor is generated to prepare all packing materials in accordance with all pattern cut shapes.
Therefore, it is necessary to use the mounting board corresponding to a plurality of pattern cut shapes in advance such that the composite materials having any pattern cut shape can be packed. However, in the article holding device described in Patent Document 2, a contact surface is formed in a linear shape such that the shape of the holding member conforms to the article, and when the contact surface holds the linear composite materials by using such a holding member, the composite materials are peeled off by the holding member, and the carbon fibers fall off and generate fluff. Such fluff may lead to a serious accident such as a conflagration due to power supply short when such fluff is stirred up in a factory during conveyance or after conveyance.
Accordingly, an object of the present invention is to solve a problem of transport of the composite materials, and to provide a package and a method of manufacturing the package that is capable of transporting the composite materials without generating fluff by suppressing shedding of carbon fibers from the composite materials while holding the composite materials in a fixed position during transport.
In order to solve the above problems, the present invention provides the following solutions.
1. A package including:
a mounting board including a plurality of fitting holes;
a plurality of plate-shaped composite materials loaded on the mounting board, the composite materials including carbon fibers and a thermoplastic resin; and
a plurality of holding membersdetachably attached to the fitting holes and holding the composite materials,
wherein, at contact surfaces between the composite materials and the holding members, one of the contact surfaces of either the composite materials or the holding members is curved, and the other contact surface is flat or curved.
2. The package according to the above 1, wherein the contact surface of the holding members are curved surfaces, and the contact surfaces of the composite materials are flat surfaces or curved surfaces.
3. The package according to the above 2, wherein curvature radii of the curved surfaces of the holding members are 15 mm to 30 mm.
4. The package according to any one of the above 1 to 3, wherein the number of the holding members is smaller than the number of the fitting holes.
5. The package according to any one of the above 1 to 4,
wherein the carbon fibers are discontinuous fibers having a weight average fiber length of 1 mm to 100 mm,
an orientation state of the carbon fibers is a two-dimensional random arrangement in which the carbon fibers are arranged randomly in an in-plane direction,
the composite materials have end surfaces including cross sections of the carbon fibers observed thereon, and
surface roughness (Rz) of the end surfaces of each composite material in contact with the holding members is 5 μm or more and 50 μm or less.
6. The package according to the above 5, wherein a carbon fiber fluff amount in the package is 0.5 g/m2 or less.
7. The package according to any one of the above 1 to 5, further including a covering board including insertion holes at positions corresponding to the fitting holes of the mounting board,
wherein the plurality of the plate-shaped composite materials are sandwiched and packed between the mounting board and the covering board, and
the holding members are inserted into the insertion holes detachably.
8. The package according to the above 7, wherein the covering board and the mounting board have the same shape.
9. The package according to any one of the above 7 or 8, further including:
a frame-shaped side wall in which the mounting board and the covering board are fitted; and
a cushioning provided in at least a part of a gap between: outer surroundings of the holding members and the composite members; and the side wall, in between the mounting board and the covering board.
10. The package according to any one of the above 1 to 9, wherein shapes of the plate-shaped composite materials are pattern cut shapes.
11. A method of manufacturing a package, including:
loading a plurality of plate-shaped composite materials including carbon fibers and a thermoplastic resin on a mounting board including a plurality of fitting holes; and
detachably attaching one end portions of a plurality of holding members to the fitting holes to hold the composite materials,
wherein, at contact surfaces between the composite materials and the holding members, one of the contact surfaces of either the composite materials or the holding members is curved, and the other contact surface is flat or curved.
Generation of fluff caused by falling off of the carbon fibers contained in the composite material can be suppressed.
[Carbon Fibers]
Composite materials used in the present invention are not particularly limited, but preferably contain carbon fibers and a thermoplastic resin. Hereinafter, a case where the composite materials contain carbon fibers will be described as a preferred aspect. A type of the carbon fibers can be appropriately selected depending on a type of the thermoplastic resin and a use of the composite materials, and is not particularly limited.
Among them, polyacrylonitrile (PAN) based carbon fibers are preferably used in terms of excellent tensile strength. When the PAN carbon fibers are used as the carbon fibers, the tensile modulus is preferably in a range of 100 GPa to 600 GPa, more preferably in a range of 200 GPa to 500 GPa, and still more preferably in a range of 230 GPa to 450 GPa. The tensile strength is preferably in a range of 2000 MPa to 6000 MPa, and more preferably in a range of 3000 MPa to 6000 MPa.
A fiber length of the carbon fibers can be appropriately selected depending on a type of the carbon fibers or a type of the thermoplastic resin, an orientation state of carbon fibers in the composite material, and the like, and is not particularly limited. Accordingly, continuous fibers or discontinuous fibers may be used depending on the purpose. When the discontinuous fibers are used, a weight average fiber length is preferably in a range of 1 mm to 100 mm. The carbon fibers whose fiber lengths are different from each other may be used together. In other words, the carbon fibers may have a single peak on an average fiber length, or a plurality of peaks.
When the carbon fibers are cut into a certain length by a rotary cutter or the like and used, the cut length corresponds to the average fiber length of the carbon fibers, which is a number average fiber length and a weight average fiber length. When the fiber length of each carbon fiber is Li and the number of measurement is j, the number average fiber length (Ln) and the weight average fiber length (Lw) are calculated by the following formulas (1) and (2) (or the weight average fiber length (Lw) is calculated with the calculation formula (1) of the number average fiber length (Ln) in a case of the certain cut length).
Ln=ΣLi/j Formula (1)
Lw=(ΣLi2)/(ΣLi) Formula (2)
Examples of the orientation state of the carbon fibers in the composite material may include a unidirectional arrangement in which long axis directions of the carbon fibers are arranged in one direction, and a two-dimensional random arrangement in which the long axis directions are randomly arranged in an in-plane direction of the composite material. The in-plane direction is an XY direction shown in
The orientation state of the carbon fibers is preferably a two-dimensional random arrangement randomly arranged in the in-plane direction. In addition, an irregular arrangement (an arrangement state in which the long axis directions of reinforced fibers are not completely arranged in one direction and are not completely random) between the unidirectional arrangement and the two-dimensional random arrangement may be used.
An orientation state of the carbon fibers in the composite material can be confirmed by, for example, performing a tensile test in an arbitrary direction of the composite material and a direction perpendicular thereto, measuring tensile moduli, and then measuring a ratio (Eδ) obtained by dividing a larger one by a smaller one of the measured tensile elastic modulus values. As the ratio of the moduli is closer to 1, it can be evaluated that the carbon fibers are arranged randomly in two dimensions. It is evaluated as isotropic when the ratio obtained by dividing the larger one with the smaller one of modulus values in two orthogonal directions does not exceed 2, and it is evaluated that the isotropy is excellent when the ratio does not exceed 1.3.
As a preferred aspect, when the composite material contains carbon fibers and a thermoplastic resin, a carbon fiber volume fraction (Vf) contained in the composite material defined by a formula (3), which is not particularly limited, is preferably 5% to 80%, more preferably 10% to 80%, furthermore preferably 10% to 70%, still more preferably 20% to 50%, and most preferably 30% to 40%.
100×(carbon fiber volume)/((carbon fiber volume)+(thermoplastic resin volume)) Formula (3)
If the carbon fiber volume fraction (Vf) is 5% or more, a reinforcing effect is liable to appear sufficiently. On the contrary, if Vf is 80% or less, a void is less likely to occur in the obtained composite material, and physical properties are liable to be improved.
[Thermoplastic Resin]
The thermoplastic resin in the present invention is not particularly limited as long as a composite material having desired strength can be obtained, and can be appropriately selected and used depending on use and the like of the composite material.
The thermoplastic resin having a desired softening point or a melting point can be appropriately selected and used, and those having a softening point in a range of 180° C. to 350° C. are used in general, but the thermoplastic resin is not limited thereto.
Examples of the thermoplastic resin can include a polyolefin resin, a polystyrene resin, a thermoplastic polyamide resin, a polyester resin, a polyacetal resin (polyoxymethylene resin) and a polycarbonate resin, a (meth)acrylic resin, a polyarylate resin, a polyphenylene ether resin, a polyimide resin, a polyether nitrile resin, a phenoxy resin, a polyphenylene sulfide resin, a polysulfone resin, a polyketone resin, a polyetherketone resin, a thermoplastic urethane resin, a fluororesin, a thermoplastic polybenzimidazole resin, and a vinyl resin.
Examples of the polyolefin resin can include a polyethylene resin, a polypropylene resin, a polybutadiene resin, and a polymethylpentene resin.
Examples of the vinyl resin can include a vinyl chloride resin, a vinylidene chloride resin, a vinyl acetate resin, and a polyvinyl alcohol resin.
Examples of the polystyrene resin can include a polystyrene resin, an acrylonitrile-styrene resin (AS resin), and an acrylonitrile-butadiene-styrene resin (ABS resin).
Examples of the polyamide resin can include a polyamide 6 resin (nylon 6), a polyamide 11 resin (nylon 11), a polyamide 12 resin (nylon 12), a polyamide 46 resin (nylon 46), a polyamide 66 resin (nylon 66), and a polyamide 610 resin (nylon 610).
Examples of the polyester resin can include a polyethylene terephthalate resin, a polyethylene naphthalate resin, a polybutylene terephthalate resin, a polytrimethylene terephthalate resin, and liquid crystal polyester. Examples of the (meth)acrylic resin can include polymethyl methacrylate.
Examples of the polyphenylene ether resin can include modified polyphenylene ether. Examples of the thermoplastic polyimide resin can include a thermoplastic polyimide, a polyamidimide resin, and a polyetherimide resin. Examples of the polysulfone resin can include a modified polysulfone resin and a polyether sulfone resin.
Examples of the polyether ketone resin can include a polyether ketone resin, a polyether ether ketone resin, and a polyether ketone ketone resin. Examples of fluororesin can include polytetrafluoroethylene.
The thermoplastic resin used in the present invention may be only one type or two or more types. Examples of an aspect in which two or more types of the thermoplastic resin are used in combination can include an aspect in which thermoplastic resins having a different softening point or melting point from each other are used in combination or an aspect in which thermoplastic resins having different average molecular weight from each other are used in combination, but are not limited thereto.
[Other Agents]
The composite material used in the present invention may contain additives such as various fibrous or non-fibrous fillers, flame retardants, UV-resistant agents, stabilizers, release agents, pigments, softening agents, plasticizers, and surfactants of organic fibers or inorganic fibers in a scope that does not impair the object of the present invention.
[Method of manufacturing composite material]
The composite material used in the present invention can be manufactured by using a generally known method, and for example, an isotropic substrate described in WO 2012/105080 Pamphlet and US 2013/0317161 is preferably used. In the composite material using the isotropic substrate, carbon fibers are not oriented in a specific direction in a plane of the composite material, but are dispersed in a random direction.
[Shapes of Composite Materials]
The shapes of the composite materials in the present invention are preferably pattern cut shapes.
In the present specification, a shape of the composite material obtained by cutting into a target shape in advance to facilitate molding is referred to as a pattern cut shape. In addition to a simple shape such as a square or a rectangle, the composite material is cut into a target shape in advance in accordance with a shape to be press-molded.
The molded article is easily molded into a target shape by cutting the composite material into the target shape in advance. For example, when a box type molded article 102 as shown in
[Package]
A plurality of plate-shaped composite materials are loaded on a mounting board including a plurality of fitting holes.
1. Mounting Board
A raw material of the mounting board and the holding members is not particularly limited, but is preferably a cardboard from the aspect of cost. For example, the plurality of fitting holes 202 are formed in the mounting board 201 in
2. Fitting Hole and Holding Member
A plurality of holding members are detachably attached to the fitting holes 202 in the present invention. As shown in
As shown in
In order to load and hold the composite material on the mounting board for a purpose of transporting the composite material, for example, as shown in
After the composite material 501 is loaded on the upper surface of the mounting board 201, the attachment regions 302 of the plurality of holding members 301 may be fitted into the fitting holes 202 to hold the composite material 501 by the holding members 301.
As a specific example,
As shown in the specific example of
3. Shape of Holding Member
In the package in the present invention, in contact surfaces between the composite material and the holding member, a contact surface of either the composite material or the holding member is a curved surface, and the other contact surface is a flat surface or a curved surface. The “contact surfaces between the composite material and the holding member” referred to herein have at least one contact surface of a plurality of contact surfaces, in which the contact surface of either the composite material or the holding member may be a curved surface, and the other contact surface may be a flat surface or a curved surface. Accordingly, the carbon fibers do not fall off from the composite material, the fluff of the carbon fibers is stirred up in a factory during conveyance or after conveyance, and a possibility leading to a serious accident, such as a conflagration due to a power supply short can be suppressed.
The contact surface in the present invention is illustrated in
In the contact surface between the composite material and the holding member in the present invention, the contact surface of the holding member is preferably a curved surface, and the contact surface of the composite material is preferably a flat surface or a curved surface. As shown in
When the contact surface of the holding member 301 is a curved surface, a curvature radius of the curved surface is more preferably 15 mm to 30 mm, and the holding member 301 even more preferably has a cylindrical shape (shape in
4. Covering Board
As shown in
Although an appropriate aspect can be used as the covering board 701, in the package in the present invention, it is preferable that a plurality of plate-shaped composite materials are sandwiched between the covering board 701 and the mounting board 201 and packed, and that the covering board 701 has insertion holes 702 at positions corresponding to the fitting holes 202 of the mounting board 201 and the holding members 301 are detachably inserted into the insertion holes 702. Incidentally, it is the other end portion on a side opposite to one end portion of the holding member 301 attached to the fitting hole 202 that is inserted into the insertion hole 702. Accordingly, the covering board 701 can be easily and accurately attached to an upper portion of the holding member 301. When the covering board 701 and the mounting board 201 have the same shape, it is preferable to manufacture the package.
5. Cushioning
The package in the present invention preferably includes cushioning 1001. The cushioning 1001 is preferably provided in at least a part of a gap between: outer surroundings of the holding member 301 and the composite members 601; and the side wall 901 of the box, in between the mounting board 201 and the covering board 701 as shown in
The cushioning 1001 may be an elastic member made of, for example, rubber or soft resin, or an air cushion such as a bubble-containing cushioning.
When such a cushioning 1001 is provided, for example, even the package is oblique when the package is transported, the holding member 301 and the composite members 601 are supported by the side wall 901 via the cushioning 1001, stress is not concentrated on the holding member 301, stress is relieved by the cushioning 1001, and a defect that the composite material 601 is scratched can be prevented.
6. Fluff Amount of Carbon Fibers
A fluff amount of carbon fibers in the package in the present invention is preferably 0.5 g/m2 or less, more preferably 0.3 g/m2 or less, and even more preferably 0.1 g/m2 or less.
In the composite material in the present invention, surface roughness (Rz) of an end surface of the composite material in contact with the holding member is preferably 5 μm or more and 50 μm or less. The end surface of the composite material is preferably excellent in surface property, particularly smoothness in view of preventing generation of a fluff amount of the carbon fibers. The surface roughness (Rz) of the composite material is 50 μm or less, so that peeling off and burrs are hardly generated on the end surface, and the fluff generation of the carbon fibers due to friction with the holding member can be prevented. The surface roughness (Rz) is preferably 30 μm or less, more preferably 25 μm or less, still more preferably 15.0 μm or less. Conversely, for example, if the surface roughness is larger than 5 μm, the adhesive is liable to penetrate into the end surface when the end surface is bonded to another member using an adhesive, so that an anchoring effect of the adhesive surface (end surface) can often be sufficiently exhibited.
7. Package
The package in the present invention refers to a package in which the stacked composite materials are held on the mounting board via the holding members, and therefore, for example, that shown
However, as a preferred embodiment, that provided with a covering board (for example,
[Transport of Package]
When the package is transported, for example, forks of a forklift can be inserted from a downside of the mounting board, and the package can be raised and conveyed by placing the package on a truck or the like. At this time, since the composite materials on the mounting board are held by the plurality of holding members in their surroundings, the composite materials can be transported in a stable state.
After the composite materials are transported to a conveyance destination, the holding members can be separated and returned to original places after the composite materials are arrived, and when the mounting board, the holding members, or the like is produced with a cardboard, they can be discarded at the conveyance destination.
As described above, the package of the present invention includes a mounting board in which the plurality of fitting holes are formed and holding members detachably attached to the fitting holes to hold the composite materials. Therefore, whatever the size or form of the composite materials is, the fitting holes are selected in accordance therewith, and the holding members are attached to the fitting holes, so that surroundings of the composite materials even having various pattern cut shapes can be held by the holding members.
Further, as shown in
In the example shown in
[Compression Molding]
The composite material in the present invention is taken out from the package and then press-molded to form a press molded article. As a preferable molding method, compression molding using a cold press or a hot press is used.
(Cold-Press Method)
In a cold-press method, for example, the composite material heated to a first predetermined temperature is put into molds at a second predetermined temperature, and then pressurized and cooled. That is, the cold-press method includes at least the following step A-1) to step A-3).
Step A-1): A step of heating the composite material to a softening temperature or higher of the thermoplastic resin contained in the composite material.
Step A-2): A step of disposing the heated composite material obtained in the above step A-1) in molds in which a temperature of the thermoplastic resin is adjusted lower than a softening temperature.
Step A-3): A step of pressurizing and molding the composite material disposed in the molds in the above step A-2).
By performing these steps, molding of the composite material can be completed.
(Hot-Press Method)
A hot-press method includes at least the following step B-1) to step B-3).
Step B-1): A step of disposing the composite material in molds Step B-2): A step of heating the molds to a softening temperature or higher of the thermoplastic resin and pressurizing the molds
Step B-3): A step of adjusting a temperature of the molds to be lower than the softening point of the thermoplastic resin to mold the molds
(With Regard to Common Items for Both Press Methods)
When the composite material is put into the molds, the composite material is used alone (one piece) or a plurality of pieces in accordance with a plate thickness of a target molded article. When a plurality of pieces are used, the plurality of pieces may be laminated and heated in advance, the heated composite material may be put into the molds after being laminated, or the heated composite material may be laminated in order in the molds. It is good that a temperature difference between the lowermost composite material and the uppermost composite material when laminated is small, and in view of this, it is preferable to laminate them before putting them into the molds.
The above steps needs to be performed in the above order, but may include other steps between the steps. Other steps include, for example, a preliminary shaping step of shaping the composite material into a shape of a cavity of the molds in advance by using the molds used in the step A-3) or the step B-2) and other shaping devices before the step A-3) or the step B-2).
The step A-3) or step B-2) is a step of obtaining a molded article having a desired shape by applying pressure to the composite material. A molding pressure at the step is not particularly limited, and is preferably less than 30 MPa, more preferably 20 MPa or less, and even more preferably 10 MPa or less with respect to a cavity projection area of the molds.
As a matter of course, various steps may be performed between the above steps during press molding, and vacuum compression molding in which press molding is performed, for example, under vacuum may be used.
[Methods for Evaluation and Analysis]
Examples are shown below, but the present invention is not limited thereto. Values in this example were determined according to the following method.
[Preparation of Raw Materials]
Raw materials used in the present invention are as follows.
Except that: carbon fibers “Tenax” (registered trademark) ST40-24KS (average fiber diameter: 7 μm) manufactured by Toho Tenax which was treated with a nylon sizing agent was used as reinforced fibers; and nylon 6 resin A1030 (melting point: 230° C.) manufactured by Unitika Ltd. was used as a thermoplastic resin, an isotropic material was produced based on a method described in Example 1 of WO 2012/105080 Pamphlet (US 2013/0317161). The isotropic material was preheated at 240° C. for 90 s and then hot-pressed at 240° C. for 180 s while applying a pressure of 2.0 MPa. Next, the composite material was cooled to 50° C. in a pressurized state to obtain a flat plate having a carbon fiber volume fraction Vf of 35%, a weight average fiber length of carbon fibers of 20 mm, and a plate thickness of 2 mm
(Cut into Pattern Cut Shape)
The obtained composite material was cut into a pattern cut shape as 501 in
(Mounting Board)
A mounting board provided with circular fitting holes as shown in
(Holding Members)
Six cylindrical paper tubes as shown in 301 of
(Covering Board)
Another one similar to the mounting board was prepared and used as a covering board.
As shown in
The package was transported with a truck for five kilometers in a factory. and when the package was opened, an amount of carbon fiber fluff contained in the package was measured to be 0.10 g. Since a size of the mounting board is 1.5 m×0.7 m (1.05 m2), when divided with this value, the fluff amount of carbon fibers contained in the package is 0.095 g/m2.
The package and the method of manufacturing the same according to the present invention can be suitably used for transporting plate-shaped composite materials containing carbon fibers and a thermoplastic resin.
Although the embodiments and examples of the present invention have been described in detail, this is only an example, and the present invention can be implemented in an aspect in which various modifications are applied in a scope not departing from the spirit. The present application is based on Japanese Patent Application No. 2016-211749 filed on Oct. 28, 2016, contents of which are incorporated herein as reference.
Number | Date | Country | Kind |
---|---|---|---|
2016-211749 | Oct 2016 | JP | national |
This is a U.S. National Phase Application under 35 U.S.C. § 371 of International Application No. PCT/JP2017/030376, filed Aug. 24, 2017, which claims priority to Japanese Application 2016-211749 filed Oct. 28, 2016, and which was published Under PCT Article 21(2), the entire contents of which are incorporated herein by reference.
Filing Document | Filing Date | Country | Kind |
---|---|---|---|
PCT/JP2017/030376 | 8/24/2017 | WO | 00 |