U.S. patent application number 15/045286 was filed with the patent office on 2016-06-09 for method for the manufacture of fibrous yarn.
The applicant listed for this patent is SPINNOVA OY. Invention is credited to Harri KIISKINEN, Antti OKSANEN, Juha SALMELA.
Application Number | 20160160399 15/045286 |
Document ID | / |
Family ID | 44718790 |
Filed Date | 2016-06-09 |
United States Patent
Application |
20160160399 |
Kind Code |
A1 |
SALMELA; Juha ; et
al. |
June 9, 2016 |
METHOD FOR THE MANUFACTURE OF FIBROUS YARN
Abstract
Disclosed is a method for the manufacture of fibrous yarn
including the steps, where an aqueous suspension including fibers
and at least one rheology modifier is provided, followed by
directing the suspension through at least one nozzle, to form at
least one yarn, and then dewatering the yarn.
Inventors: |
SALMELA; Juha; (Jyvaskyla,
FI) ; KIISKINEN; Harri; (Jyvaskyla, FI) ;
OKSANEN; Antti; (Jyvaskyla, FI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SPINNOVA OY |
Jyvaskyla |
|
FI |
|
|
Family ID: |
44718790 |
Appl. No.: |
15/045286 |
Filed: |
February 17, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14984101 |
Dec 30, 2015 |
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15045286 |
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14727118 |
Jun 1, 2015 |
9200383 |
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14984101 |
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14343928 |
Jul 9, 2014 |
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PCT/FI2012/050877 |
Sep 10, 2012 |
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14727118 |
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Current U.S.
Class: |
428/373 ;
264/204 |
Current CPC
Class: |
B29K 2301/00 20130101;
B29K 2305/00 20130101; D10B 2201/00 20130101; D21F 11/16 20130101;
D10B 2503/00 20130101; B29C 48/05 20190201; D10B 2201/01 20130101;
D01D 5/04 20130101; D01F 2/24 20130101; D10B 2201/20 20130101; D02G
3/02 20130101; D10B 2401/12 20130101; B29K 2311/10 20130101; D10B
2101/06 20130101; B29C 48/885 20190201; D01F 2/28 20130101; D02G
3/04 20130101; D02G 3/045 20130101; D10B 2505/20 20130101; D01D
5/11 20130101; D10B 2101/20 20130101; D10B 2509/02 20130101; B29K
2105/06 20130101; D10B 2501/00 20130101; D01D 10/02 20130101; D02G
3/042 20130101; D02G 3/08 20130101; D02G 3/22 20130101; D01F 2/26
20130101; D01F 1/10 20130101; B29K 2309/08 20130101; B29L 2031/707
20130101 |
International
Class: |
D02G 3/04 20060101
D02G003/04; B29C 47/88 20060101 B29C047/88; B29C 47/00 20060101
B29C047/00 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 8, 2011 |
FI |
20115882 |
Claims
1. An extruded fibrous construction or composite yarn, comprising:
fibers oriented essentially in a direction of the yarn; and at
least one rheology modifier, wherein the extruded fibrous
construction or composite yarn was produced directly from a fiber
suspension by providing an aqueous suspension comprising the fibers
and the at least one rheology modifier; directing said suspension
through at least one nozzle, to form the fibrous construction or
composite yarn, the at least one nozzle has an inner diameter of an
outlet smaller than a maximum length weighed fiber length of the
fibers; and dewatering the fibrous construction or composite
yarn.
2. The extruded fibrous construction or composite yarn according to
claim 1, wherein said fibers originate from at least one plant
based raw material source.
3. The extruded fibrous construction or composite yarn according to
claim 2, wherein said plant based raw material source is a virgin
source or recycled source or any combination thereof.
4. The extruded fibrous construction or composite yarn according to
claim 1, wherein the suspension comprises virgin or recycled fibers
originating from synthetic materials, or from natural materials, or
combinations thereof.
5. The extruded fibrous construction or composite yarn fibrous
construction or composite yarn according to claim 1, wherein the
rheology modifier is selected from the group consisting of alginic
acid, alginates, pectin, carrageenan, nanofibrillar cellulose and
combinations thereof.
6. The extruded fibrous construction or composite yarn according to
claim 1, wherein an amount of the rheology modifier is from 0.1 to
20 weight %.
7. The extruded fibrous construction or composite yarn according to
claim 1, wherein the suspension comprises at least one dispersion
agent, an anionic long chain polymer or NFC or a combination
thereof.
8. The extruded fibrous construction or composite yarn according to
claim 1, wherein the suspension comprises additives selected from
the group consisting of surfactants, hydrophobicity agents,
hydrophilicity agents, colorants, strength modifiers, elasticity
modifiers, tensile strength modifiers, decorative pieces and metal
powder.
9. The extruded fibrous construction or composite yarn according to
claim 1, wherein the suspension comprises alginates, pectin or
carrageenan and at least one dispersion agent, and the yarn is
treated with an aqueous solution comprising at least one cation
prior to dewatering.
10. The extruded fibrous construction or composite yarn according
to claim 1, wherein the dewatering is carried out with at least one
method based on vacuum, mechanical pressing and/or thermal
drying.
11. The extruded fibrous construction or composite yarn according
to claim 1, wherein the at least one nozzle comprises an inner die
or orifice, and an outer die or orifice.
12. The extruded fibrous construction or composite yarn according
to claim 1, wherein the at least one nozzle comprises an inner die
or orifice for the suspension, and an outer die or orifice for an
aqueous solution containing at least one cation.
13. The extruded fibrous construction or composite yarn according
to claim 1, wherein the at least one nozzle is arranged vertically
to provide a continuous yarn of the suspension below each nozzle,
falling freely with the aid of gravitational force.
14. The extruded fibrous construction or composite yarn according
to claim 1, wherein the at least one nozzle deviates from a
vertical position and is arranged in a vicinity of a gutter which
acts as a supporting body to the yarn.
15. The extruded fibrous construction or composite yarn according
to claim 1, wherein there are a plurality of nozzles and gutters,
and the gutters are arranged spirally on a surface of cylindrical
drums.
Description
FIELD OF THE INVENTION
[0001] The invention relates to a new method for the manufacture of
fibrous yarn, and particularly for the manufacture of paper yarn.
Further, the invention relates to fibrous yarn obtainable by said
method, as well as uses of said fibrous yarn.
BACKGROUND
[0002] Many different types of yarns made of natural fibers are
known in the art. One well known example is paper yarn, which is
traditionally manufactured from paper sheets. The first and only
industrial method was developed in the late 19.sup.th century in
Germany. It has been refined over time but the basic principle has
remained the same and it is still in use today. Typically, paper
manufactured from chemical, mechanical or chemi-mechanical pulp is
slit to strips (width typically from 5 to 40 mm), which are twisted
to thread. Said thread may be subjected to dyeing and finishing.
The product (paper yarn) has limited applications because of
deficiencies in its properties, such as limited strength,
unsuitable thickness, layered or folded structure, and further, the
manufacturing method is inefficient.
[0003] Cotton is very widely used as raw material in the
manufacture of yarns and ropes. However, the cultivation of cotton
requires significant water resources and it is widely carried out
in regions where there is shortage of water and food. When
available water is used for the irrigation of cotton fields, the
situation with regard to food supply becomes worse. Thus the use of
cotton does not support sustainable development, and there is a
need for alternative sources of fiber, suitable for replacing
cotton at least partly.
SUMMARY
[0004] An object of the present invention is to provide a new
method for the manufacture of fibrous yarn.
[0005] A further object is to provide a sustainable source of
fibers for fibrous yarn.
[0006] A still further object is to provide fibrous yarn with
improved and adjustable properties, suitable for varying
applications of yarn.
[0007] Aspects of the invention are thus directed to a method for
the manufacture of fibrous yarn, said method comprising the steps
of providing an aqueous suspension comprising fibers and at least
one rheology modifier, directing said suspension through at least
one nozzle having an inner diameter of the outlet smaller than or
equal to the maximum length weighed fiber length of the fibers, to
form at least one yarn, and subjecting said yarn to dewatering.
[0008] Aspects of the invention are also directed to a yarn
comprising fibers and at least one rheology modifier. Said yarn is
obtainable by the method described above.
[0009] Aspects of the invention are also directed to the use and
method of use of the obtained yarn in decoration, interior decor,
furniture, clothes, bandages, dressings, textiles, in construction
materials etc.
[0010] Particularly, the ease of manufacture of the fibrous yarn,
applicability of the yarn to various sites of use, possibility to
design the properties of the yarn according to the intended use,
small water footprint, biodegradability are some examples of the
desired benefits achieved by the present invention.
[0011] The characteristic features of the invention are presented
in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 depicts one embodiment of the manufacturing method,
where the yarn is produced on rotating drums.
[0013] FIG. 2 illustrates one suitable nozzle used in this
method.
DEFINITIONS
[0014] Unless otherwise specified, the terms, which are used in the
specification and claims, have the meanings commonly used in the
field of paper and pulp manufacture, as well as in the field of
yarn manufacture. Specifically, the following terms have the
meanings indicated below.
[0015] The term "yarn" refers here to thread, yarn, chord,
filament, wire, string, rope and strand.
[0016] The term "rheology modifier" is understood to mean here a
compound or agent capable of modifying the viscosity, yield stress,
thixotropy of the suspension.
DETAILED DESCRIPTION OF THE INVENTION
[0017] It was surprisingly found that fibrous yarn can be
manufactured in a very simple and efficient way directly from a
suspension comprising fibres and at least one rheology modifier,
whereby it not necessary to manufacture first paper or other
fibrous product, which is sliced into strips and wound to a
yarn.
[0018] The method according to the invention, for the manufacture
of fibrous yarn comprises the steps, where an aqueous suspension
comprising fibers and at least one rheology modifier is provided,
followed by directing said suspension through at least one nozzle
having an inner diameter of the outlet smaller than or equal to the
maximum length weighed fiber length of the fibers, to form at least
one yarn, and then subjecting said yarn to dewatering.
[0019] Here "maximum length weighed fiber length of the fibers"
means length weighted fiber length where 90% of fibers are shorter
or equal to this length. Fiber length may be measured with any
suitable method used in the art.
[0020] The aqueous suspension in understood to mean any suspension
comprising water and fibers originating from any and at least one
plant based raw material source, including cellulose pulp, refined
pulp, waste paper pulp, peat, fruit pulp, or pulp from annual
plants. The fibers may be isolated from any cellulose containing
material using chemical, mechanical, thermo-mechanical, or
chemi-thermo-mechanical pulping processes.
[0021] The plant based raw material source may be a virgin source
or recycled source or any combination thereof. It may be wood or
non-wood material. The wood can be softwood tree such as spruce,
pine, fir, larch, douglas-fir or hemlock, or hardwood tree such as
birch, aspen, poplar, alder, eucalyptus or acacia, or a mixture of
softwoods and hardwoods. The non-wood material can be plant, such
as straw, leaves, bark, seeds, hulls, flowers, vegetables or fruits
from corn, cotton, wheat, oat, rye, barley, rice, flax, hemp,
manilla hemp, sisal hemp, jute, ramie, kenaf, bagasse, bamboo, reed
or peat.
[0022] Suitably virgin fibers originating from pine may be used.
Said fibers typically may have average length weighed fiber length
from 2 to 3 mm. Also combinations of longer fibers with shorter
ones may be used, for example fibers from pine with fibers from
eucalyptus.
[0023] The aqueous suspension may comprise from 0.1 to 10% w/w,
preferably from 0.2 to 2% w/w of fibers originating from any plant
based raw material source.
[0024] Additionally the suspension may optionally comprise virgin
or recycled fibers originating from synthetic materials, such as
glass fibers, polymeric fibers, metal fibers, or from natural
materials, such as wool fibers, or silk fibers.
[0025] The aqueous suspension may comprise at least one rheology
modifier that forms a gel by crosslinking the suspension, suitably
selected from alginic acid, alginates such as sodium alginate,
pectin, carrageenan, and nanofibrillar cellulose (NFC), or a
combination of rheology modifiers. In the presence of cations,
particularly divalent or multivalent cations, suitably such as
Ca.sup.2+, Mg.sup.2+, Sr.sup.2+ or Ba.sup.2+, alginate, pectin and
carrageenan (carrageenan cross-links also with K.sup.+) readily
form a stable and strong gel. In the cross-linking of these
polysaccharides calcium chloride is preferably used. The
concentration of salt solution may vary from 1% w/w to 10% w/w.
[0026] Typically the poly-L-guluronic acid (G-block) content of
alginate, poly-D-galacturonic acid content of pectin or carrageenan
and the amount of divalent or multivalent cations (calcium ions)
are regarded as being involved in determining gel strength.
[0027] The term "nanofibrillar cellulose" or "nanofibrillated
cellulose" refers to a collection of isolated cellulose
microfibrils or microfibril bundles derived from cellulose raw
material. Microfibrils have typically high aspect ratio: the length
might exceed one micrometer while the number-average diameter is
typically below 200 nm. The diameter of microfibril bundles can
also be larger but generally less than 1 .mu.m. The smallest
microfibrils are similar to so called elementary fibrils, which are
typically 2-12 nm in diameter. The dimensions of the fibrils or
fibril bundles are dependent on raw material and disintegration
method. The nanofibrillar cellulose may also contain some
hemicelluloses; the amount is dependent on the plant source.
Mechanical disintegration of microfibrillar cellulose from
cellulose raw material, cellulose pulp, or refined pulp is carried
out with suitable equipment such as a refiner, grinder,
homogenizer, colloider, friction grinder, ultrasound sonicator,
fluidizer such as microfluidizer, macrofluidizer or fluidizer-type
homogenizer. In this case the nanofibrillar cellulose is obtained
through disintegration of plant cellulose material and can be
called "nanofibrillated cellulose". "Nanofibrillar cellulose" can
also be directly isolated from certain fermentation processes. The
cellulose-producing micro-organism of the present invention may be
of the genus Acetobacter, Agrobacterium, Rhizobium, Pseudomonas or
Alcaligenes, preferably of the genus Acetobacter and more
preferably of the species Acetobacterxylinum or
Acetobacterpasteurianus. "Nanofibrillar cellulose" can also be any
chemically or physically modified derivate of cellulose nanofibrils
or nanofibril bundles. The chemical modification could be based for
example on carboxymethylation, oxidation, esterification, or
etherification reaction of cellulose molecules. Modification could
also be realized by physical adsorption of anionic, cationic, or
non-ionic substances or any combination of these on cellulose
surface. The described modification can be carried out before,
after, or during the production of microfibrillar cellulose.
[0028] The nanofibrillated cellulose can be made of cellulose which
is chemically premodified to make it more labile. The starting
material of this kind of nanofibrillated cellulose is labile
cellulose pulp or cellulose raw material, which results from
certain modifications of cellulose raw material or cellulose pulp.
For example N-oxyl mediated oxidation (e.g.
2,2,6,6-tetramethyl-1-piperidine N-oxide) leads to very labile
cellulose material, which is easy to disintegrate to microfibrillar
cellulose. For example patent applications WO 09/084566 and JP
20070340371 disclose such modifications. The nanofibrillated
cellulose manufactures through this kind of premodification or
"labilization" is called "NFC-L" for short, in contrast to
nanofibrillated cellulose which is made of not labilized or
"normal" cellulose, NFC-N.
[0029] The nanofibrillated cellulose is preferably made of plant
material where the nanofibrils can be obtained from secondary cell
walls. One abundant source is wood fibres. The nanofobrillated
cellulose is manufactured by homogenizing wood-derived fibrous raw
material, which may be chemical pulp. When NFC-L is manufactured
from wood fibres, the cellulose is labilized by oxidation before
the disintegration to nanofibrils. The disintegration in some of
the above-mentioned equipment produces nanofibrils which have the
diameter of only some nanometers, which is 50 nm at the most and
gives a clear dispersion in water. The nanofibrils can be reduced
to size where the diameter of most of the fibrils is in the range
of only 2-20 nm only. The fibrils originating in secondary cell
walls are essentially crystalline with degree of crystallinity of
at least 55%.
[0030] Said rheology modifier may be used in an amount from 0.1 to
20 weight %. Concentration of the rheology modifier, such as
alginate is preferably 0.5-20% w/w.
[0031] The suspension may comprise also at least onedispersion
agent that is typically anionic long chained polymer or NFC, or a
combination of dispersion agents. Examples of suitable dispersion
agents are carboxymethyl cellulose (CMC), starch (anionic or
neutral) and anionic polyacrylamides (APAM), having high molecular
weight. Dispersion agent modifies the suspension rheology to make
the suspension shear thinning. Preferably at high shear rates (500
l/s) shear viscosity is less than 10% of zero shear viscosity of
the suspension.
[0032] Said dispersion agent may be used in an amount from 0.1 to
20 weight %.
[0033] Optionally the aqueous suspension may be in the form of
foam, and in that case the suspension comprises at least one
surfactant selected from anionic surfactants and non-ionic
surfactants and any combinations thereof, typically in an amount
from 0.001 to 1% w/w.
[0034] Further, the suspension may comprise other additives
selected from hydrophobicity or hydrophilicity agents, colorants,
decorative agents, elasticity modifiers, tensile strength
modifiers, or strength modifiers, such as starch, gums or
water-soluble polyelectrolytes, decorative pieces such as metal
powder etc.
[0035] The aqueous suspension is obtained using any suitable mixing
method known in the art.
[0036] In the method suspension is directed through at least one
nozzle. Suitably the amount of nozzles is selected depending on the
manufacturing equipment used and on the product which is
manufactured.
[0037] Any nozzle or extruder suitable for liquids and viscous
fluids may be used. When the suspension contains alginates, pectin
or carrageenan, suitably a nozzle is used comprising an inner die
or orifice for the suspension and outer die or orifice for an
aqueous solution comprising at least one cation (as a salt, such as
calcium chloride or magnesium sulphite). Alternatively, the
solution comprising the cation(salt)may be provided as a spray or
mist when using nozzles with one orifice. The cation, when brought
with contact for example with alginate or alginic acid, effects
very rapid increase on the viscosity of the aqueous suspension
whereby the strength of the yarn is increased, making the
embodiment of the method utilizing gravitational force very
attractive.
[0038] The inner diameter of the outlet of the nozzle is smaller
than or equal to the maximum length weighed fiber length of the
fibers. This helps to orientate the fibers essentially in the
direction of the yarn and provides strength and flexibility to the
product.
[0039] The suspension is conducted through the nozzle(s), which is
arranged suitably vertically to provide a continuous yearn of the
suspension below each nozzle, falling freely with the aid of
gravitational force. In this embodiment it is preferable to use a
suspension comprising a rheology modifier selected from alginic
acid, sodium alginate, pectin and carrageenan, together with a
solution comprising a cation. Particularly preferably the
suspension comprises also a dispersion agent. The yarn has
sufficient strength and thus no supporting bodies are needed, it
can be dewatered and subjected to finishing and other optional
steps if needed.
[0040] The nozzle(s) may also be arranged in a direction deviating
from the vertical direction. The nozzle(s) may be arranged in the
vicinity of pieces comprising gutters, where the nozzle directs the
flow of the suspension in the gutters, acting as supporting bodies,
to provide the yarn. Suitably the gutters are arranged spirally on
the surface cylindrical drums as presented in FIG. 1. The number of
nozzles is preferably the same as the number of gutters.
[0041] After the nozzle the yarn is subjected to dewatering which
may include methods based on vacuum, mechanical pressing and/or
thermal drying. The dewatering may be carried out by methods
utilizing vacuum, mechanical pressing, convection, conduction or
radiation of heat, by any suitable heating means such as heated
airflow, IR, or contact with heated surface.
[0042] After the dry yarn is obtained, it may be subjected to
optional finishing selected from pressing, twisting, shredding,
pleating, coloring, waxing and any combinations thereof.
[0043] The yarn may also be treated with dyes, wax, or silicon oil
to provide transparent yarn.
[0044] In FIG. 1 one suitable embodiment of the method according to
the invention is presented. Fiber suspension (100) comprising
fibers and at least one rheology modifier is directed, for example
by pumping or feeding from container(s) (10), which may be a pulp
tank, using any means for transferring liquids, suitably a pump
(not shown in the figure) through nozzles (20a, 20b and 20c), (30a,
30b and 30c) and (40a, 40b and 40c) to gutters (22a, 22b and 22c),
(32a, 32b and 32c) and (42a, 42b and 42c), whereby a moist yarn is
formed. Said nozzles are arranged in the vicinity of cylindrical
and rotating pieces (21), (31) and (41), suitably grooved vacuum
cylinders where the grooves or gutters are perforated, and the
outlet of each nozzle (20a, 20b and 20c), (30a, 30b and 30c) and
(40a, 40b and 40c) is arranged to direct the spray from each nozzle
to a gutter (22a, 22b and 22c), (32a, 32b and 32c) and (42a, 42b
and 42c) on the cylindrical and rotating pieces (21), (31) and
(41). In this figure the number of cylindrical pieces is three,
however it may vary from one piece to tens and even hundreds of
pieces. The cylindrical pieces may be of any suitable material,
preferably of material which can be heated. The gutters (22a, 22b
and 22c), (32a, 32b and 32c) and (42a, 42b and 42c) are formed on
surface of the cylindrical pieces and each of them form a spiral on
said piece. The form, width and depth of the gutter may be chosen
upon the yarn or product which is manufactured. The cylindrical
pieces, suitably drums, are suitably rotated at constant speed. The
moist yarn is dewatered with suitable dewatering means, such as
drying means, with heated vacuum cylindrical drums (21, 31,41),
where the heating of the drums is carried out by methods known as
such, or by providing heated air flow (60), with IR, with vacuum
(70) or with any other suitable drying means or combinations
thereof. The dry yarn (51, 52, and 53) is transferred from the
cylindrical drums to optional finishing, twisting, dyeing etc or
use.
[0045] In FIG. 2 a cross-section picture of a nozzle (200), in this
embodiment a circular nozzle is shown. The fiber suspension (210)
is fed through the inner die or orifice (201) and if salt or other
chemicals (220) are used for crosslinking they may be fed through
outer die or orifice (202). Other cross-section geometries besides
circular may as well be used, such as elliptical or
rectangular.
[0046] Moist yarn obtained from the nozzle initially contains water
typically from 30 to 99.5% w/w. In the dewatering step the yarn may
be dried to desired water content.
[0047] The invention provides several advantages. The manufacturing
method is very simple and effective, and the equipment needed is
simple and relatively cheap. The yarn is produced directly from the
fiber suspension; it is not necessary to manufacture first paper.
Traditional paper yarn may be replaced with the product obtainable
by the method, for use as replacer for traditional yarns in
textiles, decorative products, construction and composite
materials. Thinner and thicker yarns may be produced ad the
properties of the yarns may be varied, such as strength,
flexibility, colour, hydrophobicity, hydrophilicity etc.
[0048] The rheology of the fiber suspension may be adjusted using
rheology modifiers to the viscosity and thixotropy range where the
fiber suspension can be pumped through the nozzle without clogging
it, but simultaneously to provide a moist yarn typically in gel
form, which has sufficient strength to maintain its form during the
drying step. Thus the rheology modifier gives shear thinning nature
and strength to the yarn; in the case alginate is used a dispersion
agent is typically also needed and the treatment of the moist yarn
with a salt solution to provide sufficient strength. The selection
of the inner diameter of the outlet of the nozzle to smaller than
or equal to the maximum length weighed fiber length of the fibers
achieves the fibers to orientate in the direction of the yarn,
which provides the final product flexibility and strength.
[0049] The water released after drying may be recovered by
condensing and recycled in the method, for example by using a
closed system, and thus practically no wastewater is formed. Also
the amount of water needed in the process is very limited,
particularly in the embodiment where the fiber suspension is
provided in the form of foam.
[0050] Very thin to very thick yarns and ropes may be produced,
which may be twisted together to provide products suitable for
weaving, knitting, manufacture of carpets, blankets, textiles,
dressings etc. Also very soft yarns may be produced for example
from bamboo with alginates, particularly suitable for the
manufacture or textiles and clothes. Further, very thick ropes may
be produced, which may be used for example in interior decoration
etc. purposes, as well as yarn and rope suitable for construction
industry and in the manufacture of composite structures where the
yarn is embedded in a matrix, such as a polymer. The composition of
the fiber suspension may be adjusted according to the product that
is manufactured.
[0051] The product is completely biodegradable if the starting
materials used are natural materials.
[0052] The need of cotton may be reduced with the method and
products of the present invention, where the fibers originate at
least partly from more ecological plant material, such as wood and
recycled paper.
[0053] Particularly, long fiber pulp, suitably manufactured from
Nordic pine, may be used in the method to provide a yarn having the
thickness of less than 0.1 mm and very good strength
properties.
[0054] While the invention has been described with respect to
specific examples presented in the figures, including presently
preferred modes of carrying out the invention, those skilled in the
art will appreciate that there are numerous variations and
permutations of the above described embodiments that fall within
the spirit and scope of the invention. It should be understood that
the invention is not limited in its application to the details of
construction and arrangements of the components set forth herein.
Variations and modifications of the foregoing are within the scope
of the present invention.
* * * * *