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Knowledge on Glass fiber

What is Glassfiber?

Glass fiber is the first inorganic fiber produced industrially,
and is used in a wide range of industries due to its characteristics such as strength, heat resistance,
nonflammability, electrical insulation and chemical resistance.
In recent years, it has expanded to various applications such as building materials,
FRP (fiber reinforced plastic), and electrically insulating cloth for printed wiring boards.
Therefore, it is widely recognized by the world's industry
and is an important material indispensable to the industry.

As the name implies, glass fiber is a fiber made from glass,
but it has various shapes such as long fibers like threads (long fibers)
and those with a soft feel like glass wool (short fibers)...
These products are used properly according to their purpose.

  • Long Glass fiber

    • Yarn, roving, glass cloth, mat, powder, etc.
    • Main applicationsInsulating material, reinforcing material, shaving material, etc.

  • Short Glass fiber

    • glass wool
    • Main applicationsInsulation materials, sound absorbing materials, heat insulating materials, etc.
Glass fiber manufacturing method (raw fiber)Glass fiber manufacturing method (raw fiber)
Glass fiber manufacturing method (Glass cloth)Glass fiber manufacturing method (Glass cloth)

Knowledge on Resin materials & Molding methods

What are thermosetting resins and thermoplastic resins? Thermosetting resin flows when heat is applied, and cures when heat is continued. It does not flow even if it is recooled or reheated.
On the other hand, thermoplastic resins soften and flow when heated, and harden when cooled. When this is reheated, it softens and flows again.
Among thermoplastic resins, the resin mainly used for industrial parts is called engineering plastic.

thermosetting resins

etc.

Molding of thermosetting resin

etc.

thermoplastic resins

Molding of thermoplastic resin

etc.

  • Unsaturated polyester resin

    Unsaturated polyester resin is a condensation of unsaturated dibasic acid such as maleic anhydride and saturated dibasic acid such as phthalic anhydride and glycols.
    There are many applications for FRP (Fiber Reinforced Plastics) that make molded products by impregnating glass fibers with thermosetting resin. There are also non-FRP applications that are used without fiber reinforcement such as casting and paint.

  • Vinyl ester resin

    Vinyl ester resin is a thermosetting resin in which a polymer obtained by reacting an epoxy resin with (meth) acrylic acid is dissolved with a crosslinkable monomer or the like.
    Due to its excellent acid resistance, alkali resistance, and mechanical properties, it is used in corrosion-resistant applications such as pipes and septic tanks, and in structural members of automobiles.

  • Epoxy resin

    Epoxy resin is a general term for resins that have an epoxy group in the molecule. The most common type is the phenolic glycidyl ether type, and the most typical and most frequently used type is the epoxy resin obtained by the condensation of bisphenol A and epichlorohydrin.
    It has electrical insulation, heat resistance, and adhesiveness, and is used in applications such as electrical parts, paints, civil engineering, and adhesives.

  • Urethane resin

    Urethane resin is a reaction of a compound having two or more isocyanate groups in the molecule and a compound having two or more hydroxyl groups.
    There are thermosetting type and thermoplastic type.
    It is used in applications such as foams, paints, adhesives, elastomers, and elastic fibers.

  • Phenol resin

    Phenol resin is based on the addition polymerization reaction of phenols and aldehydes, and there are two types: novolak type with acid catalyst and resol type with alkali catalyst.
    It has excellent electrical insulation and is used for electrical appliances and vehicle electrical components.

  • Polyethylene resin

    Polyethylene has a structure in which ethylene is polymerized, and has various properties such as low-density polyethylene and high-density polyethylene depending on the manufacturing method and molecular weight.
    It is used for applications such as films and containers.

  • Polypropylene resin

    Polypropylene is a thermoplastic resin obtained by polymerizing propylene in which one hydrogen of ethylene is substituted with a methyl group.
    Cold resistance, transparency, and mechanical properties vary depending on the type of polymerization catalyst and copolymer composition. Among general-purpose resins, it boasts the highest heat resistance, has the lowest specific gravity, and floats on water.
    As a general-purpose resin, it has excellent chemical resistance and good heat resistance and water resistance.
    It is used in a wide range of applications such as stationery, home appliances, automobile parts, packaging materials, and textile products.

  • Polystyrene resin

    Polystyrene includes transparent general-purpose polystyrene obtained by polymerizing styrene in which one hydrogen of ethylene is replaced by a benzene ring, and milky white High-impact polystyrene whose impact resistance is improved by adding styrene-butadiene rubber.
    It is used in packaging films, home appliances such as televisions, and office equipment. Foamed polystyrene is used for blocks and fish boxes.

  • Polyvinylchloride resin

    Polyvinyl chloride is a thermoplastic resin obtained by substituting one hydrogen of ethylene with chlorine and polymerizing it. Vinyl chloride resin is classified according to the amount of plasticizer added, and there are two types, hard and soft.
    For hard plasticizer, the amount of plasticizer added is small. A large amount of plasticizer is added to the soft material. A typical plasticizer is DOP, but the type of plasticizer is changed according to the required performance.
    It is often used for housing construction and civil engineering, and is used for pipes and gutters for hard materials, and for flooring and hoses for soft materials.

  • Acrylonitrile-Butadiene-Styrene resin

    ABS resin is an acrylonitrile, butadiene, and styrene copolymer resin with excellent design, mechanical properties, and chemical resistance.
    There are various impact grades depending on the blending ratio of butadiene.
    It is used for vehicles, sports equipment, leisure equipment, toys and other miscellaneous goods, vacuum cleaners and other home appliances, and OA equipment.

  • Acrylonitrile-Ethylene-Styrene resin

    AES resin uses ethylene propylene rubber instead of butadiene rubber, has the same basic characteristics as ABS, and has improved weather resistance.
    It is used in applications such as automobile parts, OA equipment, and housing parts.

  • Acrylonitrile-Styrene resin

    AS resin is a copolymer resin of acrylonitrile and styrene.
    A transparent non-crystalline plastic with excellent rigidity and impact resistance like ABS resin.
    Although it is sensitive to heat, it is easy to process.
    It is used in home appliances such as refrigerator trays, automobile parts, and daily necessities that take advantage of its transparency and impact resistance.

  • Thermoplastic elastomer

    Thermoplastic elastomer is a general term for polymers that have elastic and stretchable properties such as rubber.
    It is molded by injection molding and extrusion molding because it softens when heat is applied and returns to a rubber shape when cooled.
    There are various types of elastomers such as styrene type and olefin type.
    It is not suitable for applications that require heat resistance because it is easily deformed by heat. However, due to its nature, it is used in a wide range of applications from automobiles to daily necessities.

  • Polyethylene terephthalate

    Polyethylene terephthalate is a polyester obtained by polycondensation terephthalic acid or dimethyl terephthalate with ethylene glycol.
    Although it has the property of slow crystallization rate, it becomes easier to make it transparent by cooling it rapidly so that it does not develop a crystal structure.
    It is used for fiber, films, PET bottles, etc.

  • Polycarbonate

    Polycarbonate is a general term for polymers that have a carbonic acid ester structure in their molecular structure. It has strengths such as transparency, weather resistance, impact resistance, and heat resistance.
    It is possible to make polymers of any molecular weight from high molecular weight with high fluidity to high molecular weight with impact characteristics.
    It is used for optical discs such as DVDs, lens barrels made of glass fiber reinforced grade, various automobile parts such as headlamp lenses, and glass replacement.

  • Polybutylene terephthalate

    Polybutylene terephthalate is a type of thermoplastic polyester that has an ester integration in the molecule. Many grades contain glass fiber due to the glass transition temperature.
    It has low hygroscopicity and water absorption, and has little change in dimensions, mechanical properties, and electrical properties.
    It is used in the fields of electrical and electronic parts such as connectors and the field of automobiles for switch parts.

  • Modified polyphenylene ethers

    Modified polyphenylene ethers are available in PPE(excellent in heat resistance, mechanical properties, and electrical properties) alloyed grades of PS(completely compatible), PA(high heat resistance) and PP(low hygroscopicity and low specific gravity).
    It has excellent electrical properties such as dielectric properties and electrical insulation, and is used in applications in the automobile field such as hubcaps and in the electrical and electronic fields such as adapters.

  • Polyphenylene sulfide

    Polyphenylene sulfide is a crystalline synthetic resin with a structure in which benzene rings and sulfur are repeated alternately. There are oxidative cross-linked PPS that is thermally cross-linked in the presence of oxygen and linear PPS that has a high molecular weight only in the polymerization process.
    Filler reinforced (glass fiber, etc.) grades are often used.
    It has heat resistance, high rigidity, electrical properties, and flame retardancy, and is used as an electrical component in the electronic and electrical fields such as connectors and in the automobile field.

  • Polyamide

    Polyamide is a resin that has an amide bond in the main chain, and there are various types depending on the type of monomer and its combination. The most used are PA6 and PA66.
    Due to the glass transition temperature, composite grades containing glass fibers are used under high temperature and high stress.
    The moisture absorption rate and water absorption rate are large, and the changes in dimensions and mechanical properties are large.
    It has excellent chemical resistance, impact resistance, and wear resistance, and is used in applications such as gears and coil bobbins that are subject to heat resistance and high load.

injection molding

Injection molding is a molding method that uses an injection molding machine and a mold to inject molten resin into a mold at high pressure and cool it to manufacture a product.
The general flow is to melt the material, inject it into the mold, cool the material with the mold, remove it from the mold, and fine-tune the product. Products with complicated shapes are also possible, and it is also possible to continuously mass-produce them, and they are being developed in various fields.

injection moldinginjection molding
Extrusion moldingExtrusion molding

Extrusion molding

Extrusion molding is a molding method that uses an extrusion molding machine and a mold to extrude and cool the molten resin from the mold that has the desired shape.
It is suitable for manufacturing long and mass products of various shapes by using a mold.

Blow molding

Blow molding is a molding method that uses an extrusion molding machine and a mold to sandwich the molten resin in the mold and blow compressed air to cool it to manufacture the product.
Suitable for molding bottle shapes.

Blow moldingBlow molding
Vacuum formingVacuum forming

Vacuum forming

Vacuum forming is the process of using a sheet-shaped material and a mold, placing the heated and softened sheet-shaped material on the mold, and creating a shape by creating a vacuum between the sheet and the mold and cooling it. It is a molding method to manufacture products with.

Knowledge on FRP

FRP (fiber reinforced plastic) is the material which has strengthened the resin
by a glass fiber and a carbon fibre or aramid fiber, etc..
The size shape of the end product, mechanical characteristics and the cost, etc.
fluctuate by a molding method. We'll introduce a production technique of typical glassfiber reinforced plastic here.

FRP(Hand layup)

Hand layup moldingHand layup molding is a molding method in which resin is manually impregnated into glass fibers with a brush or roller, and the glass fibers are laminated to a specified thickness while defoaming. This molding method is the most common molding method.

  • Strengths

    • It's suitable for high-variety low-volume manufacturing.
    • There is little investment in plant and equipment.
    • It's possible to form a complicated product.

  • Weakness

    • The working environment is bad.
    • Fibre content is low because it's formation pressure-lessly.
    • Product quality depends on the skill of the worker.
FRP(Hand layup)FRP(Hand layup)
Spray up mouldingSpray up moulding

Spray up moulding

Spray up moulding is the way to blow resin into shaping dies at the same time and mold while cutting roving in the suitable length using a spray up machine.

  • Strengths

    • Compared with hand layup molding, the cutting process of glass material can be reduced.
    • The production efficiency is excellent to that of the hand layup moulding.

  • Weakness

    • Spray-up molding requires capital investment.
    • The quality control by which it's for fiber content is difficult.
    • The working environment is bad.

Filament Winding

Filament winding molding is a molding method in which multiple rovings are drawn, wrapped around a rotating mold while impregnated with resin, cured, and then demolded. This molding method is the molding method for which the strength of the fibre reinforcement was used most effectively in the molding method of glass fiber reinforced plastic (fiber reinforced plastic).

  • Strengths

    • Among FRP, high strength can be obtained because the glass content is high.
    • Quality is stable due to machine molding.
    • Highly productive because it can be automated.

  • Weakness

    • Investment in plant and equipment is needed.
    • Mainly cylindrical and spherical, limited to rotating bodies, and there are restrictions on the shape. (Application examples: pipes, pressure vessels, fishing rods, golf club shafts, etc.)
Filament WindingFilament Winding
SMC moldingSMC molding

SMC molding

The material used for SMC molding method is SMC (Sheet Molding Compound).
SMC is a sheet-like material in which a chopped strand is impregnated with a resin paste containing a resin, a curing agent, a thickener, an internal mold release agent, a filler, etc., and both sides are covered with a film.
SMC molding is a molding method in which an SMC sheet is cut, filled in a mold, and heated under pressure to cure.

  • Strengths

    • Suitable for mass production.
    • Good working environment
    • Ribs, bosses, inserts, screws, etc. can be molded at the same time, with high dimensional accuracy and excellent quality due to machine molding.

  • Weakness

    • Expensive investment to the equipment (Presses, Mold, Heating equipment, etc.)
    • The strength is low relatively.

BMC molding

BMC (Bulk Molding Compound) is a pellet-like material made by mixing chopped strands and resin.
Compression, transfer, and injection molding are used as molding methods.

  • Strengths

    • Suitable for mass production of complex shapes.
    • Since a large amount of filler can be used, dimensional accuracy is improved.
    • It's possible to automate whole process flow.

  • Weakness

    • The reinforcement effect of fiber is small relatively.
    • Expensive investment to the equipment.
BMC moldingBMC molding
Pultrusion moldingPultrusion molding

Pultrusion molding

In pultrusion, the reinforcing fiber material is impregnated with resin and passed through a heated mold to cure the resin.
A hardened composite is produced as it out the mold.
After then, it can be cut to the specified length to obtain a molded product with the same cross section.

  • Strengths

    • Suitable for molding continuous cross sections.
    • I Suitable for mass production.
    • Excellent strength characteristics.

  • Weakness

    • Multi-product low-volume production is not suitable.
    • Expensive investment to the equipment.

About the safety of Glass fiber

What happens if you smoke glass fiber?
QWhat happens if you inhale glass fiber?
AGlass fiber is an artificially manufactured amorphous fiber.
Even if it breaks, the thickness of the fiber does not change.
It is difficult to reach deep into the lungs, and even if it gets inside, it will be expelled from the body by the body's defense mechanism.
What is the effect on the skin?
QWhat is the effect on the skin?
AGlass fiber is an inert substance.
You may feel itchy when you touch the surface of the skin.
However, there are few cases of dermatitis or allergies.
In rare cases, if inflammation occurs in people with sensitive skin, it can be eliminated by removing the glass fibers.
Difference between asbestos and fiberglass
QDifference between asbestos and fiberglass
AAsbestos is a natural crystalline mineral fiber, which is an aggregate of extremely fine fibers of 1 micron or less.
In addition, it breaks further into fine fibers in the body, and stays in the body as foreign matter without being discharged while being stuck in the alveoli.
It causes a variety of illnesses.
On the other hand, glass fiber is an artificially manufactured amorphous fiber (non-crystalline fiber), and even if it breaks, the thickness of the fiber does not change, so it is difficult for it to be absorbed by the body. Even if inhaled, they would not remain in the body. If you would like to confirm the details regarding safety, please refer to the website of the Glass Fiber Association.