GB2208364A - Production of fiber reinforced plastic article - Google Patents

Production of fiber reinforced plastic article Download PDF

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Publication number
GB2208364A
GB2208364A GB8818042A GB8818042A GB2208364A GB 2208364 A GB2208364 A GB 2208364A GB 8818042 A GB8818042 A GB 8818042A GB 8818042 A GB8818042 A GB 8818042A GB 2208364 A GB2208364 A GB 2208364A
Authority
GB
United Kingdom
Prior art keywords
fiber
mold
article
flexible tube
tube
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
GB8818042A
Other versions
GB2208364B (en
GB8818042D0 (en
Inventor
Ichiro Tominaga
Taketo Matsuki
Tetsuo Yamaguchi
Hiroomi Matsushita
Kunio Niwa
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Sumitomo Rubber Industries Ltd
Original Assignee
Sumitomo Rubber Industries Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from JP62193124A external-priority patent/JPS6436420A/en
Priority claimed from JP62193125A external-priority patent/JPH0622914B2/en
Application filed by Sumitomo Rubber Industries Ltd filed Critical Sumitomo Rubber Industries Ltd
Publication of GB8818042D0 publication Critical patent/GB8818042D0/en
Publication of GB2208364A publication Critical patent/GB2208364A/en
Application granted granted Critical
Publication of GB2208364B publication Critical patent/GB2208364B/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
    • B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
    • B29C70/28—Shaping operations therefor
    • B29C70/30—Shaping by lay-up, i.e. applying fibres, tape or broadsheet on a mould, former or core; Shaping by spray-up, i.e. spraying of fibres on a mould, former or core
    • B29C70/34—Shaping by lay-up, i.e. applying fibres, tape or broadsheet on a mould, former or core; Shaping by spray-up, i.e. spraying of fibres on a mould, former or core and shaping or impregnating by compression, i.e. combined with compressing after the lay-up operation
    • B29C70/347—Shaping by lay-up, i.e. applying fibres, tape or broadsheet on a mould, former or core; Shaping by spray-up, i.e. spraying of fibres on a mould, former or core and shaping or impregnating by compression, i.e. combined with compressing after the lay-up operation combined with compressing after the winding of lay-ups having a non-circular cross-section, e.g. flat spiral windings
    • A—HUMAN NECESSITIES
    • A63—SPORTS; GAMES; AMUSEMENTS
    • A63B—APPARATUS FOR PHYSICAL TRAINING, GYMNASTICS, SWIMMING, CLIMBING, OR FENCING; BALL GAMES; TRAINING EQUIPMENT
    • A63B49/00—Stringed rackets, e.g. for tennis
    • A63B49/02—Frames
    • A63B49/10—Frames made of non-metallic materials, other than wood
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
    • B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
    • B29C70/28—Shaping operations therefor
    • B29C70/40—Shaping or impregnating by compression not applied
    • B29C70/42—Shaping or impregnating by compression not applied for producing articles of definite length, i.e. discrete articles
    • B29C70/46—Shaping or impregnating by compression not applied for producing articles of definite length, i.e. discrete articles using matched moulds, e.g. for deforming sheet moulding compounds [SMC] or prepregs
    • B29C70/48—Shaping or impregnating by compression not applied for producing articles of definite length, i.e. discrete articles using matched moulds, e.g. for deforming sheet moulding compounds [SMC] or prepregs and impregnating the reinforcements in the closed mould, e.g. resin transfer moulding [RTM], e.g. by vacuum
    • A—HUMAN NECESSITIES
    • A63—SPORTS; GAMES; AMUSEMENTS
    • A63B—APPARATUS FOR PHYSICAL TRAINING, GYMNASTICS, SWIMMING, CLIMBING, OR FENCING; BALL GAMES; TRAINING EQUIPMENT
    • A63B2209/00—Characteristics of used materials
    • A63B2209/02—Characteristics of used materials with reinforcing fibres, e.g. carbon, polyamide fibres
    • A63B2209/023—Long, oriented fibres, e.g. wound filaments, woven fabrics, mats
    • A—HUMAN NECESSITIES
    • A63—SPORTS; GAMES; AMUSEMENTS
    • A63B—APPARATUS FOR PHYSICAL TRAINING, GYMNASTICS, SWIMMING, CLIMBING, OR FENCING; BALL GAMES; TRAINING EQUIPMENT
    • A63B49/00—Stringed rackets, e.g. for tennis
    • A63B49/02—Frames
    • A63B49/10—Frames made of non-metallic materials, other than wood
    • A63B49/11—Frames made of non-metallic materials, other than wood with inflatable tubes, e.g. inflatable during fabrication
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
    • B29K2105/00—Condition, form or state of moulded material or of the material to be shaped
    • B29K2105/04—Condition, form or state of moulded material or of the material to be shaped cellular or porous
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
    • B29L2031/00—Other particular articles
    • B29L2031/46—Knobs or handles, push-buttons, grips
    • B29L2031/463—Grips, handles
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
    • B29L2031/00—Other particular articles
    • B29L2031/52—Sports equipment ; Games; Articles for amusement; Toys
    • B29L2031/5245—Rackets

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Composite Materials (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Health & Medical Sciences (AREA)
  • General Health & Medical Sciences (AREA)
  • Physical Education & Sports Medicine (AREA)
  • Laminated Bodies (AREA)
  • Injection Moulding Of Plastics Or The Like (AREA)
  • Moulding By Coating Moulds (AREA)

Abstract

A process for preparing a fiber reinforced plastic article by a reaction injection molding method, comprising the following steps; (a) winding reinforcing fiber around a flexible tube, (b) placing it in a mold, (c) either pouring a foaming agent in said flexible tube followed by foaming and curing it, or pouring an uncured foam followed by curing it, and (d) injecting a reaction-injection-molding composition between said mold and said flexible tube to cure. The article may be a shaft of a golf club or a frame of a tennis raquet.

Description

PRODUCTION OF FIBER REINFORCED PLASTIC ARTICLE The present invention relates to a process for preparing a fiber reinforced plastic article which is useful for a frame of a tennis racket, a shaft of a golf club, a pipe-like structural member and the like.
A fiber reinforced plastic article, such as a frame of a tennis racket and a shaft of a golf club, is generally lightened by hollowing it.
In order to make the article hollow, it is subjected to a holing process, which, however, is time and cost consuming. The holding process also is difficult to apply an article having a complicated shape. Another method is also proposed wherein reinforcing fiber impregnated with a thermosetting resin is wound around a mandrel and put in a mold, and then after curing the resin the mandrel is pulled out. This method, however, is only applicable to a linear article and impossible for a complicated shaped article.
Further, there has been proposed a method wherein reinforcing fiber impregnated with a thermosetting resin, such as an epoxy resin, is wound around a foamed core and pressed in a mold while heating and curing. If this method is applied to reaction injection molding in which a reactive composition is injected into a mold including a fiber-wound core, it is difficult that the fiber-wound core is tightly put in the mold, thus occuring the problem of the salience of raw materials (such as fiber and the like). The salience causes leaking of the reactive composition. If the size of the wound core is small sufficient not to occur the salience of raw materials, the fiber does not align tightly and closely along with the shape of the mold and also the resin layer of the molded article becomes so thick that a fiber content is poor.Also, if the article has a complicated shape, the fiber does not align along with the mold and a thickness of the resin layer is uneven.
A method has also proposed wherein reinforcing fiber impregnated with a thermosetting resin is wound around a flexible tube, which is put in a mold and to which an air pressure is applied. If this method is applied to reaction injection molding, that is, if without using a thermosetting resin a reaction injection molding composition is injected between the tube and the mold, it is very difficult to keep a balance between a tube inside pressure and an injecting pressure due to flexibility of the air pressured tube, thus resulting in ununiformity of the resin thickness.
The present invention provides a process for preparing a fiber reinforced article having a resin layer of an uniform thickness. The process is applicable to an article having any complicated shape.
The present invention is to provide a process for preparing a fiber reinforced plastic article by a reaction injection molding method, comprising the following steps; (a) winding reinforcing fiber around a flexible tube, (b) placing it in a mold, (c) either pouring a foaming agent in said flexible tube followed by foaming and curing it, or pouring an uncured foam followed by curing it, and (d) injecting a reaction-injection-molding composition between said mold and said flexible tube to cure.
The reaction injection molding method (hereinafter referred to as "RIM method") is a method wherein at least two monomers which are reactive with each other are introduced into a mold and reacted at ambient temperature or an elevated temperature. The obtained resin type can be polyurethane, polyamide and the like. If the monomers employed for the RIM method are a polyisocyanate and a polyol, the obtained resin is a polyurethane type.
Selection of monomers for the RIM method are known to the art, depending upon the obtained resin type. Such a reaction injection molding composition are available.
Preferred for the present invention is UBE Nylon (UX-21) available from Ube Industries, Limited.
The reinforcing fiber employed in the present invention can be any one that is employed in this field.
Representative examples of the fibers are aramid fiber, carbon fiber, glass fiber and the like. Preferred is carbon fiber. The fiber can be any shape and may be either woven or unwoven. Preferred is woven.
The flexible tube used in the present invention can be made of nylon, cellophane, rubber, polyester, polyetherketone and the like.
The foaming agent of the present invention is one which foams and cures under a foaming condition. It is generally a liquid or solid resin impregnated with a foamable material. Preferred examples of the foaming agent are DIC RPll47B, DIC SP299 (both available from Dainippon Ink and Chemical Inc.) and a mixture thereof.
The uncured foam is one which has been foamed but which is not cured yet, for example syntactic foam composition. Preferred is those which impregnate an epoxy resin, a phenol resin, a polyester resin or a urethane resin with a foaming agent, such as UCAR phenolic microbloon BJO0930 available from Union Carbide Company and Expane Cell DE available from Nippon Philite Company.
According to the present invention, the flexible tube is wound with reinforcing fiber and then put in a mold. The foaming agent or uncured foam is poured into the tube to cure and then the reaction injection molding composition is injected between the tube and the mold to obtain a desirable fiber reinforced plastic article.
Another embodiment of the present invention, the fiber wound tube is further wound with unwoven fabric. This embodiment effectively inhibits defective molding or defective appearance, such as exposure of fibers to the surface. Also, it significantly enhances the colorability of the obtained articles to provide an article having excellent appearance.
According to the present invention, since the foam is cured inside of the tube and in the mold, the tube and reinforcing fiber is tightly shaped to the mold to enhance the accuracy of thickness of the resin layer. No deformation of the tube by an applied pressures, as is seen in case where air is filled in the tube, occurs and therefore ununifomity of the resin layer thickness is effectively prevented. The process of the present invention is very suitable for sports goods, such as tennis rackets, shafts of golf clubs and the like, because they require high accuracy of a resin layer thickness.
The invention will be described with reference to the drawings, in which Fig. i shows cut portions (I to IV) of the tennis racket of Exmple 2; and Fig. 2 shows measuring portions (1 to 4) of the cut portions of Example 2 Examples The present invention is illustrated by the following examples which, however, are not to be construed as limiting it to their details.
Example 1 Each of a cellophane tube and a nylon tube was covered with three carbon fiber woven sleeves and placed in a mold. A foaming agent (a 1 : 1 mixture of DIC RP 1147H and DIC SP 299, both of which are available from Dainippon Ink and Chemical Ltd.) was injected into the tube and, after closing the injected end of the tube, reacted at about 40 0C for 2 or 3 minutes. The other end was closed when foaming was bulged out therefrom. A 1 : 1 mixture (90 OC) of A and B liquids of UBE Nylon (UX-21) available from Ube Industries, Ltd. was injected at respectively 0.3 Kg/cm2 and 1.5 Kg/cm2 to the vacuumed mold of which temperature kept at 150 OC. Its molding properties are shown in Table 1.
Comparative Example 1 A carbon fiber reinforced article was obtained as generally described in Example 1, with the exception that air was injected at an inner pressure of 1.2 Kg/cm2 instead of the foaming agent. Its molding properties are shown in Table 1.
Table 1
Injecting pressure Example 1 Comparative Example 1 (Kg/cm Cellophane Nylon Cellophane Nylon 0.3 Usual per- Usual per- Tube Bad per meability meability bursting meability 1.5 Good per- Good per- Tube Tube meability meability bursting bursting Permeability was visually evaluated by observing a polished cut section through a light microscope.
Example 2 A nylon tube having a length of 160 cm and a diameter of 16.5 cm was covered with two ply of carbon fiber blades available from Toho Rayon Co., Ltd. as BC 7664-24 and placed in a mold of a tennis racket's frame. After elevating a temperature of the mold to 40 OCI 60 g of the same foaming agent mixture as Example 1 was injected to the tube and then a temperature of the mold was elevated to 150 CC. Then, the same reaction injection molding composition as Example 1 was injected to the fiber layer at an injection pressure of 3.0 Kg/cm2 to form a tennis racket's frame.
Thicknesses of the portions 1 to 4 (see Fig. 2) at I to IV (see Fig.l) were determined and shown in Table 2.
Table 2
I II III IV Average mm mm mm mm mm 1 1.0 1.1 0.9 1.2 1.1 2 1.3 1.0 1.0 1.2 1.1 3 1.0 0.9 0.9 1.1 1.98 4 ~ 1.4 1.1 1.1 1.0 1,2 Average 1.2 1.0 0.98 1.1 1.1 Deviation 0.18 0.083 0.083 0.096 0.067 Example 3 A tennis racket's frame was obtained as generally described in Example 2, with the exception that a fiber wound tube was further spirally wound with a 30 mm width glass fiber paper tape having a fiber density of 11 Vol % (available from Nippon Sheet Glass Co., Ltd. as UL4A 30) and that the RIM composition was injected at an injection pressure of 1.5 Kg/cm2. The molded article has good surface finish and therefore no buff or putty coat is needed.
Inserting the fiber paper layer significantly reduces the time for a puff or putty coating process.
Example 4 The molded article obtained in Example 3 was buffed by a # 360 sand paper and dyed at 90 0C for 20 minutes by using the following dye solution; Ingredients Parts by weight (%) Brown pigmentsl 2.0 Ammonia water 0.5 Ammonium sulfate 1.0 Water 96.5 1 Available from Sumitomo Chemical Industries, Inc.
as Lanyl Brown GR.
Thereafter, a urethane type clear paint was coated on the dyed article to obtain an article having a transparent and excellent color.
Example 5 A colored tennis racket's frame was obtained as generally described in Example 4, with the exception that Lanyl Blue 3G was employed instead of Lanyl Brown GR. The obtained article also has uniform color.
According to a conventional method, the molded article is black and is needed to be coated with white putty if it is necessary to change color. Dying is impossible, because the article is made of an epoxy resin. However, according to the present invention, since the unwoven fabric is employed, coloring can be easily carried out, thus obtaining tennis rackets having various colors. If the unwoven fabric is made of glass fiber, the color of an article can be widely selected. If the unwoven fabric is made of carbon fiber, the color of an article becomes transparent, deep and glossy dark color. If the unwoven fabric is not employed, its color became spotted.

Claims (1)

  1. What is claimed is
    1. A process for preparing a fiber reinforced plastic article by-a reaction injection molding method, comprising the following steps; (a) winding reinforcing fiber around a flexible tube, (b) placing it in a mold, (c) either pouring a foaming agent in said flexible tube followed by foaming and curing it, or pouring an uncured foam followed by curing it, and (d) injecting a reaction injection molding composition between said mold and said flexible tube to cure.
    2. The process according to Claim 1 wherein said reinforcing fiber is glass fiber or carbon fiber.
    3. The process according to Claim 1 wherein said flexible tube is made of nylon and cellophane.
    4. The process according to Claim 1 wherein in the step (a) said wound tube is further wound by unwoven fabric.
    5. The process according to Claim 4 wherein said unwoven fabric is made of glass fiber or carbon fiber.
    5. A process as claimed in claim 1 and -.
    substantially as hereinbefore described in anyone of the examples .
    7. An article prepared by the process according to anyone of the preceding clåims.
    8. An article according to Claim 7 which is a shaft of a golf club or a frame of a tennis racket.
GB8818042A 1987-07-31 1988-07-28 Production of fiber reinforced plastic article Expired - Fee Related GB2208364B (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP62193124A JPS6436420A (en) 1987-07-31 1987-07-31 Manufacture of fiber-reinforced plastic product
JP62193125A JPH0622914B2 (en) 1987-07-31 1987-07-31 Manufacturing method of fiber reinforced plastic products

Publications (3)

Publication Number Publication Date
GB8818042D0 GB8818042D0 (en) 1988-09-01
GB2208364A true GB2208364A (en) 1989-03-30
GB2208364B GB2208364B (en) 1990-09-19

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GB8818042A Expired - Fee Related GB2208364B (en) 1987-07-31 1988-07-28 Production of fiber reinforced plastic article

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0547330A2 (en) * 1991-10-19 1993-06-23 Sumitomo Rubber Industries Limited Method for manufacturing product made of fiber-reinforced resin and product manufactured by method
FR2716376A1 (en) * 1994-02-24 1995-08-25 Wilson Sporting Goods Resin transfer racket frame reinforced with continuous fibers.
FR2716378A1 (en) * 1994-02-24 1995-08-25 Wilson Sporting Goods Method of manufacturing a game racket frame in coiled filaments.
WO1996004124A1 (en) * 1994-08-01 1996-02-15 G. Schwartz Gmbh & Co. Kg Process for producing moulded parts by polymerisation of lactams in moulds
CN107344005A (en) * 2016-05-06 2017-11-14 黑德技术有限公司 Ball match racket with magnesium bridge portion

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109940904A (en) * 2019-01-28 2019-06-28 徐建昇 The forming method of high quality fibers pipe fitting

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1436755A (en) * 1972-06-08 1976-05-26 Fischer Gmbh Racket and a method for its production
GB2172238A (en) * 1985-03-12 1986-09-17 Diversified Prod Racquets

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1436755A (en) * 1972-06-08 1976-05-26 Fischer Gmbh Racket and a method for its production
GB2172238A (en) * 1985-03-12 1986-09-17 Diversified Prod Racquets

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0547330A2 (en) * 1991-10-19 1993-06-23 Sumitomo Rubber Industries Limited Method for manufacturing product made of fiber-reinforced resin and product manufactured by method
EP0547330A3 (en) * 1991-10-19 1993-10-13 Sumitomo Rubber Industries Limited Method for manufacturing product made of fiber-reinforced resin and product manufactured by method
FR2716376A1 (en) * 1994-02-24 1995-08-25 Wilson Sporting Goods Resin transfer racket frame reinforced with continuous fibers.
FR2716378A1 (en) * 1994-02-24 1995-08-25 Wilson Sporting Goods Method of manufacturing a game racket frame in coiled filaments.
WO1996004124A1 (en) * 1994-08-01 1996-02-15 G. Schwartz Gmbh & Co. Kg Process for producing moulded parts by polymerisation of lactams in moulds
US5980796A (en) * 1994-08-01 1999-11-09 G. Schwartz Gmbh & Co. Kg Process for producing molded parts by polymerization of lactams in molds
CN107344005A (en) * 2016-05-06 2017-11-14 黑德技术有限公司 Ball match racket with magnesium bridge portion

Also Published As

Publication number Publication date
GB2208364B (en) 1990-09-19
GB8818042D0 (en) 1988-09-01

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PCNP Patent ceased through non-payment of renewal fee

Effective date: 20050728