Title of Invention	A MAT AND METHODS FOR THE MANUFACTURE OF GLASS FIBER REINFORCED PLASTICS OR CARBON FIBER REINFORCED PLASTICS
Abstract	A method for manufacturing glass fiber reinforced plastics or carbon reinforced plastics, comprising: - applying a resin-impregnated laminate to a rotating mold; - winding the laminate around by a first gas-permeable and liquid-permeable peel-ply; and surrounding the peet-ply by a mat as a layer for the absorption of excess resin consisting of thermally bonded plastic fibers, with at least one side of the mat so that the solidified surface with the smaller pore size of the mat is arranged adjacent to the first peel-ply.

Title of Invention

A MAT AND METHODS FOR THE MANUFACTURE OF GLASS FIBER REINFORCED PLASTICS OR CARBON FIBER REINFORCED PLASTICS

Abstract

A method for manufacturing glass fiber reinforced plastics or carbon reinforced plastics, comprising: - applying a resin-impregnated laminate to a rotating mold; - winding the laminate around by a first gas-permeable and liquid-permeable peel-ply; and surrounding the peet-ply by a mat as a layer for the absorption of excess resin consisting of thermally bonded plastic fibers, with at least one side of the mat so that the solidified surface with the smaller pore size of the mat is arranged adjacent to the first peel-ply.

Full Text	A mat and methods for the manufacture of glass fiber reinforced plastics or carbon fiber reinforced plastics The invention relates to a mat for use in a method for the manufacture of glass fiber reinforced plastics or carbon fiber reinforced plastics and to methods for the manufacture of glass fiber reinforced plastics or carbon fiber reinforced plastics using this new mat. Various methocs of manufacture are known for glass fiber reinforced plastics or carbon fiber reinforced plastics. In addition to manual lamination in which unheated open molds, for example wooden molds, are used as the mold, vacuum processes or also centrifugal processes have gained acceptance. A centrifugal method in accordance with the prior art is explained schematically in Figure 1. Resin-impregnated laminate 12. which is surrounded by a peel-ply 14 which, as such, is permeable to gas and liquid, is there placed onto a drum 10 rotating in the direction of the arrow a. This first peel-ply 14 is surrounded by a second peel-ply 16 which consists of a polyamide fabric. When the drum 10 is spun in the direction of the arrow a, excess resin is expelled from the resin-impregnated laminate coating 12 and passes through the first peel-ply to penetrate into the second peel-ply 16. Due to the fabric structure of this fabric layer, consisting for example of polyamide, resin is expelled during the spinning and contaminates the vicnity of the centrifuge apparatus. After the hardening of the resin, it is usually very difficult to separate the peel-ply, which is in another respect rigid and less flexible, from the peel-ply 14 on the drum 10. In Figure 3, another manufacturing process for a glass fiber reinforced plastic or a carbon fiber reinforced plastic is shown schematically. A mold 102 is placed on a table 100 here and resin-impregnated laminate 104 has been layered onto or into it. A peel-ply 106 has been laid around the resin-impregnated laminate 104. The peel- ply 106 is surrounded by a permeable separating foil 108. This is in turn surrounded by means of an absorbing layer 110. The absorbing layer 110 is in turn enveloped by means of a gas-tight foil 112 which is sealed to the side via seals 114. Vacuum suction devices 116 are provided inside the gas-tight foil 112 and the vacuum can be applied via these. This vacuum is distributed uniformly through the absorbing layer 110 such that excess resin from the laminate 104 is transported into the absorbing layer 110 via the air-permeable and liquid-permeable peel-ply 106 and via the permeable separating foil 108. After hardening the glass fiber reinforced plastic or carbon fiber reinforced plastic, the individual foils can be separated from the laminate 104 comparatively easily in the present method, in particular due to the permeable separating foil 108. The assembly present here for the carrying out of the method is, however, comparatively complex and expensive since a series of different layers have to be applied to the laminate 104. It is the object of the invention to provide a new mat for use in a method for the manufacture of glass fiber reinforced plastics or carbon fiber reinforced plastics with which these methods can be simplified and made cheaper. Th s object is solved in accordance with the invention by a mat for use in a method for the manufacture of glass fiber reinforced plastics or carbon fiber reinforced plastics in accordance with claim 1. A mat is provided here as a layer for the absorption of excess resin expelled during the manufacturing process which consists of thermally bonded plastic fibers, with at least one side of the mat having a solidified surface with a smaller pore size in comparison to the remaining pore size of the mat. This mat has a series of advantages. It can be used either in a centrifugal method or in a vacuum method for the manufacture of glass fiber reinforced plastics or carbon fiber reinforced plastics. It has been found that the mats in accordance with the invention can store the discharged resin ideally when used in the centrifugal method. After hardening the resin, they can be easily separated from the peel-ply of the drum due to their solidified surface with a small pore size. Even with the absorbed and hardened resin, the mat in accordance with the invention is so flexible that it can be rolled up and so handled easily. When used in the vacuum method, the mat can replace two layers, namely the permeable separating foil and the absorbing layer arranged above this. The permeable separating film, which is to be provided separately, can be replaced due to the solidified surface properties of smaller pore sizes. This surface namely makes it possible to peel of the mat in a simple manner from the first peel-ply which is arranged directly over the resin-impregnated laminate. Particularly advantageous aspects of the mat in accordance, with the invention result from the dependent claims 2 to 9 following the main claim. Accordingly, the mat can have a basis weight from 50 g/m2 up to 1000 g/m2. A mat having a basis weight from 100 g/m2 up to 600 g/m2 is particularly preferred. !t furhermore has a preferable thickness from 0.3 mm up to 12 mm. Fir ally, the mat in accordance with the invention consists of polypropylene, polyester and/or polyamide fibers or of mixtures of these materials. If the fibers forming the mat have been manufactured in a melt-blown method , they advantageously have 0.01 dtex up to 0.5 dtex (microfibers). If they are manufactured in a different method, they preferably have 0.8 dtex up to 20 dtex. The mats can consist of fine fibers or the mats can consist either of thick fibers or of a mixture of thick and fine fibers. The fine fibers permit the manufacture of mats having a fine pore size, whereas the thick fibers serve for mats with a good absorption property. These properties can advantageously be combined in mat production, for instance for the manufacture of multi-ply mats, for example, with the individual layers consisting of fibers of different thicknesses. This invention further relates to a centrifugal method in accordance with claim 10 and to a vacuum method in accordance with claim 11. Details and advantages of the invention will be explained in more detail with reference to two embodiments shown in the drawing. There are shown: Figure 1: a schematic representation of a centrifugal method in accordance with the prior art; Figure 2: a schematic representation of a centrifugal method to illustrate a first embodiment of the present invention; Figure 3 a schematic representation of a vacuum method in accordance with the prior art; and Figure 4 a schematic representation of a vacuum method in accordance with a further embodiment of the present invention in accordance with the invention. A centrifugal process is shown schematically in Figure 2 which substantially corresponds to that already described in accordance with Figure 1. Here, however, a layer consisting of a mat 18 is provided instead of the outer layer of polyamide fabric 16 as is used in accordance with the prior art in accordance with Figure 1. The layer 18 consists of a mat which has been manufactured from thermally bonded plastic fibers, with at least one side of the mat having a solidified surface with a pore size which is smaller than the pore size of the remaining mat. This sol dified surface permits a particularly favorable interface property with respect to the first peel-ply 14 which, as such, is liquid permeable and gas permeable. Due to the correspondingly set pore size, the resin.is thus here held back in the laminate 12, on the one hand, and some is absorbed into the mat and stored there, on the other hand. On the other hand, due to the solidified surface with a small pore size, a removal of the mat 18 from the peel-ply 14 is possible without problem. Due to the properties of the mat, it can also be rolled up with the resin absorbed and stored in the mat and so can be easily disposed of. It is particularly advantageous that no unwanted resin edges form on the surface of the hardened glass fiber reinforced plastic 12 or carbon fiber reinforced plastic 12. The circular drum 10 shown in the representation 2 can also be another mold of any desired shape. A vacuum method is shown schematically in Figure 4 using the mat in accordance with the invention. This substantially corresponds to that in accordance with Figure 3, which was previously described as the prior art. However, the permeable separating foil 108 and the absorbing layer 110 are here replaced by the mat 120. On the one hand, the permeable separating foil 108 in accordance with Figure 3 and the absorbing layer 110 in accordance with Figure 3 are here replaced by a single layer, namely the mat 120. The handling is hereby substantially simplified, on the one hand. The new method is also more cost-favorable than the multi-ply method in accordance with the prior art. Due to the pore structure of the mat, a very good distribution of the vacuum over the whole laminate structure 104 is ensured, on the one hand. The excess resin is absorbed over an equal area, on the other hand. A smooth and regular surface without corners and edges or faults in the glass fiber reinforced plastic component or carbon fiber reinforced plastic component to be shaped is hereby ensured. The mat 120 or 18 is mainly manufactured from thermoplastic fibers made of polypropylene, polyester, polyamide and/or copolymers of these materials. Staple fibers, endless fibers, bicomponent fibers or mixtures thereof are used. The manufacturing method of the mat as such is known and will therefore not be explained again in detail here. A customary mat, a needle mat, a spun-bonded mat, a melt-blown mat, an air-laid mat can be used alone or in combination as the mat 120 or 18. It is important that one side of the mat has a solidified surface with a comparatively smaller pore size. This solidification can be created, for example, by heat treatment of the surface or also by other method steps. With the mat 120 or 18 in accordance with the invention, a very good flexibility results in the absorption capacity for the excess resin by adaptation of the basis weight of the mat 120 or 18 or by overlapping a plurality of layers of the mat. More absorption volume to accept the excess resin can thus be made available by the correspondingly selected basis weight or by a multiple layer of the mat. WE CLAIM: 1. A method for manufacturing glass fiber reinforced plastics or carbon reinforced plastics, comprising: applying a resin-impregnated laminate to a rotating mold; - winding the laminate around by a first gas-permeable and liquid-permeable peel-ply; and - surrounding the peel-ply by a mat as a layer for the absorption of excess resin consisting of thermally bonded plastic fibers, with at least one side of the mat so that the solidified surface with the smaller pore size of the mat is arranged adjacent to the first peel-ply. 2. A method for manufacturing glass fiber reinforced plastics or carbon reinforced plastics, comprising: - applying a resin-impregnated laminate to a mold; - surrounding the laminate by a liquid-permeable and gas- permeable peel-ply; - applying a mat as a layer for absorption of excess resin expelled during the manufacturing process consisting of thermally bonded plastic fibers, with at least one side of the mat having a solidified surface with a smaller pore size compared to the remaining pore size of the mat, such that the side of the mat with the solidified surface and the smaller pore sizes is arranged adjacent to the peel-ply; and - surrounding the mat by a vacuum-tight foil, with suction openings being provided in the latter via which a vacuum can be applied. 3. The method as claimed in claim 1 or 2, wherein the mat has a basis weight between 50 g/m2, up to 1000 g/m2 preferably 100 g/m2 up to 600 g/m2. 4. The method as claimed in claims 1 to 3, wherein the mat has a layer thickness of from 0.3 mm to 10 mm. 5. The method as claimed in claims 1 to 4 wherein the mat consists of at least one of polypropylene fibers, polyester fibers, polyamide fibers, and fibers of copolymers of the aforesaid materials. 6. The method as claimed in claims 1 to 5, wherein the microfibers forming the mat are manufactured in a melt-blown method and have 0.01 dtex upto 0.5 dtex. 7. The method as claimed in claims 1 to 6, wherein the fibers forming the mat have 0.8 dtex upto 20 dtex. 8. The method as claimed in claims 1 to 7, wherein the mat consists of fine fibers or thick fibers or of a mixture of thick and fine fibers. 9. The method as claimed in claims 1 to 8, wherein the fine fibers permit a fine pore size and wherein the thick fibers permit a good absorption property. 10. The method as claimed in claim 9, wherein the mat has at least one surface with a layer of fine fibers with a small pore size and attached thereto a layer with thick fibers with a good absorption property. A method for manufacturing glass fiber reinforced plastics or carbon reinforced plastics, comprising: - applying a resin-impregnated laminate to a rotating mold; - winding the laminate around by a first gas-permeable and liquid-permeable peel-ply; and surrounding the peet-ply by a mat as a layer for the absorption of excess resin consisting of thermally bonded plastic fibers, with at least one side of the mat so that the solidified surface with the smaller pore size of the mat is arranged adjacent to the first peel-ply.

Full Text

A mat and methods for the manufacture of glass fiber reinforced plastics or carbon
fiber reinforced plastics
The invention relates to a mat for use in a method for the manufacture of glass fiber
reinforced plastics or carbon fiber reinforced plastics and to methods for the
manufacture of glass fiber reinforced plastics or carbon fiber reinforced plastics
using this new mat.
Various methocs of manufacture are known for glass fiber reinforced plastics or
carbon fiber reinforced plastics. In addition to manual lamination in which unheated
open molds, for example wooden molds, are used as the mold, vacuum processes
or also centrifugal processes have gained acceptance.
A centrifugal method in accordance with the prior art is explained schematically in
Figure 1. Resin-impregnated laminate 12. which is surrounded by a peel-ply 14
which, as such, is permeable to gas and liquid, is there placed onto a drum 10
rotating in the direction of the arrow a. This first peel-ply 14 is surrounded by a
second peel-ply 16 which consists of a polyamide fabric. When the drum 10 is spun
in the direction of the arrow a, excess resin is expelled from the resin-impregnated
laminate coating 12 and passes through the first peel-ply to penetrate into the
second peel-ply 16. Due to the fabric structure of this fabric layer, consisting for
example of polyamide, resin is expelled during the spinning and contaminates the
vicnity of the centrifuge apparatus. After the hardening of the resin, it is usually very
difficult to separate the peel-ply, which is in another respect rigid and less flexible,
from the peel-ply 14 on the drum 10.
In Figure 3, another manufacturing process for a glass fiber reinforced plastic or a
carbon fiber reinforced plastic is shown schematically. A mold 102 is placed on a
table 100 here and resin-impregnated laminate 104 has been layered onto or into it.
A peel-ply 106 has been laid around the resin-impregnated laminate 104. The peel-
ply 106 is surrounded by a permeable separating foil 108. This is in turn surrounded
by means of an absorbing layer 110. The absorbing layer 110 is in turn enveloped
by means of a gas-tight foil 112 which is sealed to the side via seals 114. Vacuum
suction devices 116 are provided inside the gas-tight foil 112 and the vacuum can
be applied via these. This vacuum is distributed uniformly through the absorbing
layer 110 such that excess resin from the laminate 104 is transported into the
absorbing layer 110 via the air-permeable and liquid-permeable peel-ply 106 and
via the permeable separating foil 108. After hardening the glass fiber reinforced
plastic or carbon fiber reinforced plastic, the individual foils can be separated from
the laminate 104 comparatively easily in the present method, in particular due to the
permeable separating foil 108. The assembly present here for the carrying out of
the method is, however, comparatively complex and expensive since a series of
different layers have to be applied to the laminate 104.
It is the object of the invention to provide a new mat for use in a method for the
manufacture of glass fiber reinforced plastics or carbon fiber reinforced plastics with
which these methods can be simplified and made cheaper.
Th s object is solved in accordance with the invention by a mat for use in a method
for the manufacture of glass fiber reinforced plastics or carbon fiber reinforced
plastics in accordance with claim 1. A mat is provided here as a layer for the
absorption of excess resin expelled during the manufacturing process which
consists of thermally bonded plastic fibers, with at least one side of the mat having
a solidified surface with a smaller pore size in comparison to the remaining pore
size of the mat. This mat has a series of advantages. It can be used either in a
centrifugal method or in a vacuum method for the manufacture of glass fiber
reinforced plastics or carbon fiber reinforced plastics. It has been found that the
mats in accordance with the invention can store the discharged resin ideally when
used in the centrifugal method. After hardening the resin, they can be easily
separated from the peel-ply of the drum due to their solidified surface with a small
pore size. Even with the absorbed and hardened resin, the mat in accordance with
the invention is so flexible that it can be rolled up and so handled easily.
When used in the vacuum method, the mat can replace two layers, namely the
permeable separating foil and the absorbing layer arranged above this. The
permeable separating film, which is to be provided separately, can be replaced due
to the solidified surface properties of smaller pore sizes. This surface namely
makes it possible to peel of the mat in a simple manner from the first peel-ply which
is arranged directly over the resin-impregnated laminate.
Particularly advantageous aspects of the mat in accordance, with the invention
result from the dependent claims 2 to 9 following the main claim.
Accordingly, the mat can have a basis weight from 50 g/m2 up to 1000 g/m2. A mat
having a basis weight from 100 g/m2 up to 600 g/m2 is particularly preferred. !t
furhermore has a preferable thickness from 0.3 mm up to 12 mm.
Fir ally, the mat in accordance with the invention consists of polypropylene,
polyester and/or polyamide fibers or of mixtures of these materials.
If the fibers forming the mat have been manufactured in a melt-blown method , they
advantageously have 0.01 dtex up to 0.5 dtex (microfibers). If they are
manufactured in a different method, they preferably have 0.8 dtex up to 20 dtex.

The mats can consist of fine fibers or the mats can consist either of thick fibers or of
a mixture of thick and fine fibers. The fine fibers permit the manufacture of mats
having a fine pore size, whereas the thick fibers serve for mats with a good
absorption property. These properties can advantageously be combined in mat
production, for instance for the manufacture of multi-ply mats, for example, with the
individual layers consisting of fibers of different thicknesses.
This invention further relates to a centrifugal method in accordance with claim 10
and to a vacuum method in accordance with claim 11.
Details and advantages of the invention will be explained in more detail with
reference to two embodiments shown in the drawing.
There are shown:
Figure 1: a schematic representation of a centrifugal method in accordance with
the prior art;
Figure 2: a schematic representation of a centrifugal method to illustrate a first
embodiment of the present invention;
Figure 3 a schematic representation of a vacuum method in accordance with the
prior art; and
Figure 4 a schematic representation of a vacuum method in accordance with a
further embodiment of the present invention in accordance with the
invention.
A centrifugal process is shown schematically in Figure 2 which substantially
corresponds to that already described in accordance with Figure 1. Here, however,
a layer consisting of a mat 18 is provided instead of the outer layer of polyamide

fabric 16 as is used in accordance with the prior art in accordance with Figure 1.
The layer 18 consists of a mat which has been manufactured from thermally
bonded plastic fibers, with at least one side of the mat having a solidified surface
with a pore size which is smaller than the pore size of the remaining mat. This
sol dified surface permits a particularly favorable interface property with respect to
the first peel-ply 14 which, as such, is liquid permeable and gas permeable. Due to
the correspondingly set pore size, the resin.is thus here held back in the laminate
12, on the one hand, and some is absorbed into the mat and stored there, on the
other hand. On the other hand, due to the solidified surface with a small pore size, a
removal of the mat 18 from the peel-ply 14 is possible without problem. Due to the
properties of the mat, it can also be rolled up with the resin absorbed and stored in
the mat and so can be easily disposed of. It is particularly advantageous that no
unwanted resin edges form on the surface of the hardened glass fiber reinforced
plastic 12 or carbon fiber reinforced plastic 12. The circular drum 10 shown in the
representation 2 can also be another mold of any desired shape.
A vacuum method is shown schematically in Figure 4 using the mat in accordance
with the invention. This substantially corresponds to that in accordance with Figure
3, which was previously described as the prior art. However, the permeable
separating foil 108 and the absorbing layer 110 are here replaced by the mat 120.
On the one hand, the permeable separating foil 108 in accordance with Figure 3
and the absorbing layer 110 in accordance with Figure 3 are here replaced by a
single layer, namely the mat 120. The handling is hereby substantially simplified, on
the one hand. The new method is also more cost-favorable than the multi-ply
method in accordance with the prior art. Due to the pore structure of the mat, a very
good distribution of the vacuum over the whole laminate structure 104 is ensured,
on the one hand. The excess resin is absorbed over an equal area, on the other
hand. A smooth and regular surface without corners and edges or faults in the glass
fiber reinforced plastic component or carbon fiber reinforced plastic component to
be shaped is hereby ensured.

The mat 120 or 18 is mainly manufactured from thermoplastic fibers made of
polypropylene, polyester, polyamide and/or copolymers of these materials. Staple
fibers, endless fibers, bicomponent fibers or mixtures thereof are used. The
manufacturing method of the mat as such is known and will therefore not be
explained again in detail here. A customary mat, a needle mat, a spun-bonded mat,
a melt-blown mat, an air-laid mat can be used alone or in combination as the mat
120 or 18. It is important that one side of the mat has a solidified surface with a
comparatively smaller pore size. This solidification can be created, for example, by
heat treatment of the surface or also by other method steps.
With the mat 120 or 18 in accordance with the invention, a very good flexibility
results in the absorption capacity for the excess resin by adaptation of the basis
weight of the mat 120 or 18 or by overlapping a plurality of layers of the mat. More
absorption volume to accept the excess resin can thus be made available by the
correspondingly selected basis weight or by a multiple layer of the mat.
WE CLAIM:
1. A method for manufacturing glass fiber reinforced plastics or carbon
reinforced plastics, comprising:
applying a resin-impregnated laminate to a rotating mold;
- winding the laminate around by a first gas-permeable and
liquid-permeable peel-ply; and
- surrounding the peel-ply by a mat as a layer for the absorption
of excess resin consisting of thermally bonded plastic fibers,
with at least one side of the mat so that the solidified surface
with the smaller pore size of the mat is arranged adjacent to the
first peel-ply.
2. A method for manufacturing glass fiber reinforced plastics or carbon
reinforced plastics, comprising:
- applying a resin-impregnated laminate to a mold;
- surrounding the laminate by a liquid-permeable and gas-
permeable peel-ply;
- applying a mat as a layer for absorption of excess resin expelled
during the manufacturing process consisting of thermally bonded
plastic fibers, with at least one side of the mat having a solidified
surface with a smaller pore size compared to the remaining pore
size of the mat, such that the side of the mat with the solidified
surface and the smaller pore sizes is arranged adjacent to the
peel-ply; and

- surrounding the mat by a vacuum-tight foil, with suction openings
being provided in the latter via which a vacuum can be applied.
3. The method as claimed in claim 1 or 2, wherein the mat has a basis
weight between 50 g/m2, up to 1000 g/m2 preferably 100 g/m2
up to 600 g/m2.
4. The method as claimed in claims 1 to 3, wherein the mat has a layer
thickness of from 0.3 mm to 10 mm.
5. The method as claimed in claims 1 to 4 wherein the mat consists of at
least one of polypropylene fibers, polyester fibers, polyamide fibers, and
fibers of copolymers of the aforesaid materials.
6. The method as claimed in claims 1 to 5, wherein the microfibers forming
the mat are manufactured in a melt-blown method and have 0.01 dtex upto
0.5 dtex.
7. The method as claimed in claims 1 to 6, wherein the fibers forming the
mat have 0.8 dtex upto 20 dtex.
8. The method as claimed in claims 1 to 7, wherein the mat consists of fine
fibers or thick fibers or of a mixture of thick and fine fibers.
9. The method as claimed in claims 1 to 8, wherein the fine fibers permit a
fine pore size and wherein the thick fibers permit a good absorption property.
10. The method as claimed in claim 9, wherein the mat has at least one
surface with a layer of fine fibers with a small pore size and attached thereto
a layer with thick fibers with a good absorption property.
A method for manufacturing glass fiber reinforced plastics or carbon
reinforced plastics, comprising: - applying a resin-impregnated laminate to a
rotating mold; - winding the laminate around by a first gas-permeable and
liquid-permeable peel-ply; and surrounding the peet-ply by a mat as a layer
for the absorption of excess resin consisting of thermally bonded plastic
fibers, with at least one side of the mat so that the solidified surface with the
smaller pore size of the mat is arranged adjacent to the first peel-ply.

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Patent Number

225412

Indian Patent Application Number

00766/KOLNP/2004

PG Journal Number

46/2008

Publication Date

14-Nov-2008

Grant Date

12-Nov-2008

Date of Filing

04-Jun-2004

Name of Patentee

FIBERTEX A/S

Applicant Address

SVENDBORGVEJ 16 DK-9220 AALBORG OST

Inventors:

#	Inventor's Name	Inventor's Address
1	LAURIDSEN, KELD	HELIOSVEJ 22 9220 ALBORG

PCT International Classification Number

B29C 70/44

PCT International Application Number

PCT/EP02/13379

PCT International Filing date

2002-11-27

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	10160956	2001-12-12	Germany