TATSUTA Spinning offers a new approach to the circular economy for carbon fiber.
Recycled carbon fiber (rCF) is recovered from end-of-life vehicles, aircraft, and other products.
Conventional recycling methods mill recycled carbon fiber into fine powder.
However, once carbon fiber loses its length, its reinforcing effectiveness in composite materials is significantly reduced.
Moreover, when fibers become too short, they cannot be recycled into high-performance materials again.
With our proprietary spinning technology, recycled carbon fiber can be reused repeatedly in a sufficiently long form.
This enables true circulation of carbon fiber while maintaining high material performance.
Have you ever heard of the circular economy?
It is an economic system based on minimizing waste and continuously utilizing resources by keeping materials in use for as long as possible.
Instead of the traditional “produce-use-dispose” model, resources are recovered, regenerated, and reused to create sustainable value.
Roving made with carbon fiber has been produced before. However, roving made entirely from carbon fiber had not been achieved.
Producing roving with a high carbon fiber content is difficult. Carbon fiber has no crimp and, unlike cotton used in conventional spinning, does not easily entangle with other fibers. For this reason, roving has generally been produced by blending in crimped synthetic fibers.
TATSUTA Spinning has succeeded in producing roving made from 100% carbon fiber, without any additional materials.
Plain weave fabric can be produced using carbon fiber roving.
Plain weave is a basic weaving structure in which warp (lengthwise) and weft (crosswise) yarns cross alternately in an over-and-under pattern.
Carbon fiber roving can also be used to produce knitted fabrics.
Carbon fiber in filament form is too stiff to be knitted, but when it is made into roving, it becomes soft enough for knitting.
It can also be processed into braided cord.
Braiding is a structure created by intertwining three or more yarns diagonally to form a tubular shape.
Sliver is the material stage before roving.
Carbon fibers, either used alone or blended with synthetic fibers, are evenly mixed and aligned in one direction.
The fibers are not tightly bound and remain in a soft, fluffy state. For this reason, sliver is considered to have good resin impregnation.
Sliver has good resin impregnation.
However, during press molding, the fibers may flow out together with the resin when pressure is applied.
To address this issue, needle punching is used to fix the sliver into a thin nonwoven sheet.
The backing material of the sliver sheet can be changed according to the application, such as to a resin mat or a glass mat.
Carbon fibers with a length of approximately 50mm are opened and mixed with thermoplastic resin fibers of the same length (e.g., PA6, PA66, PP, PET).
The fiber mixing ratio can be adjusted according to customer requirements. This process can also be applied to carbon fibers alone, without thermoplastic resin fibers.
The fibers prepared in step 1 are processed using a carding machine to separate fiber bundles, promote fiber alignment, and form them into a continuous fiber assembly.
The fibers are oriented predomnantly in the longitudinal direction and collected into string like bundles referred to as slivers.
Multiple slivers produced in the carding process are combined and drawn using a drawing machine.
This process improves fiber straightness, enhances alignment, and reduces thickness irregularities, resulting in a more uniform drawn sliver.
The drawn sliver is further attenuated using a roving frame, then lightly twisted to provide cohesion.
The twisted fiber bundle is subsequently wound onto a bobbin as roving.