Note: Descriptions are shown in the official language in which they were submitted.
KG - DND nF TUE INV~NTION
Ths pre~nt invention relate~ to improvement~ in insula~ion,
and in particular to the u~a of bonded mono-acrylic, ac.rylic
or polyamide, polyester and like synthetic or cellulose fibres
either alone or in combination with animal fibres and either
in batt form or a~ ' blow inl in~ulation.
With the pre~ent energy cost~, con~ervation of heat
is highly d~rabl~. One m~thod of con~erving heat in the
dome~ia scene i~ to insulate th~ dwelling. Fibregla~s in~ula-tion
l~ u~ed exten~lvely in thi~ ld, although it is hazardous
to health, and di~ficult *o handle in batts by reason of the
gla~s ~ibxe~. Use o~ chemlcala to ran~er 'blow in' ~ibreglass
fire-retarding i~ also h~alth hazardous.
BACKGROUND MT
In the Australian Patent No. 527,843 granted to Richard
L. Lewellin there is disclosed a me~hod o~ forming an insulation
batt of bonded fibres, at l~a~t 95% of which are wool fibres.
The method involves ragging and teasi~g wool ~ibres o~ waste
wool, wool ~econd~ and ~he like, and matting tha randomly dispersed
wool fibre~ to produae a b~tt o~ ~he required thickness. The
bat~ i3 then ~prayed wlth ~ira r~tardant, resin~, pe~ticides,
etc. a~d the rasin~ are ~t by cu~ing.
However, it l8 o~t0n di~ficult to obtain wa~te products
having a hiyh wool aont~nt. I~ ha~ ~ee~ found, however, that
other fibre~, whe~ ~ui~bly .troated and fo~med into a batt:,
will bond tvgether ~nd with wool ~ibre~ to ~nable a ~uitable
in~ulating batt to be ~oxmed.
.~acordingly, ~ a~ object o~ th0 i~ventlon to provide
an improved ~eth~d o~ producing an in~ulating b~t~ or an insulating
loose material formed o~ wa~te tex ile a~d o~her matarials
which do not nece~arll~ includ~ a high ~mount af wool fibres.
A ~urther obja¢t of the pre~ent invention i8 to provide
an in~ulation which i~ not hazardous ~o the health, but yet
has all the proper~ie~ o~ ~xisting ins~lation.
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S AE~Y OF THE :[NVENTIOM
According:Ly, the presen-t invention provides
a method of formi.ng a batt of bonded fibres for use
as insulation, said fibres comprising monoacrylic,
acrylic or other synthetic or cellulose fibres with
from 25 to 80~, wool fibres, said batt being formed by
ragging, teasing and o-therwise doffering the fibres
of was-te textile and other materials to form a
randomly dispersed ~ibre sliver, passing said sliver
through a lapper to ob-tain a mat of desired -thick-
ness, spraying said mat to impregnate it wi-th resin
or resins, which may comprise fireproofing resin or
resins, and, op-tionally, smoke re-tardants, and
pesticides, set-ting the resins by curing, preferably
in an oven, and cut-ting -the batt to the desired
lengths.
The bonded fibres have a plurality of air
pockets which assi.sts in -the insulation effec-ts. If
desired for a 'blow in' installation, the ba-tts may
be broken down into small balls of bonded fibre in
loose form.
Use of wool fibres in amoun-ts between 25%
and 80r~ of total fibres is preferred having regard to
the known fire-retardant properties of wool. In
addition, it is rot proof and vermin proof. As -the
insulation is not visible in the finished ins-talla-
tion, it i.s possible -to make use of wool 'seconds',
especially black fleeces, cuttings from the shearing
sheds and recycled woollen jumpers and other
garments.
Other fibres which are combined with the
wool fibres and which are particularly useful in -the
invention inclu~e monoacrylic, acrylic, polyamide and
polyester synthetic fibres as well as other natural
-3-
a~
~ibres such as cotton. These types oE Eibres, when
matted and bonded together in a bat-t, preferably wi-th
additionally wool fibres, resul-ts in an insulation
material which is extremely economical -to produce,
which can be formed of waste clothing and other waste
materials and which has excellent insula-ting proper-
ties wi-thout the hazards of o-ther known insulating
produc-ts.
Resins suitable for use in the present
invention include flame depressants such as modified
acrylic self-crosslinking polymers such as RHOPLEX
HA-20; trademark, available from Rohn & Haas. O-ther
additives -to the spray include Aluminium Trihydra-te
and
-3a-
23~L
Xem Gard (Trade Mark) (I.C.I~ smoke 4uppres~ant) and Perigen
(Trade ~ark) ~ p~ticide~ s~pecially ~uitable against clothe~
moths and carp~t baetle and available rom Burrough~ Wellcome.
The insulation o formed may be used in any location
i~e. in home, office, fac ory or ~ther building, for either
heat or acoustic insulatiQn~
In ordar ~hat the invsntion may be more clearly understood,
a preferred embodime~t the~eof will now be described.
DESC~IPTION OF PR~FERRED ~M~ODIMENT
A mi~ture of ragged acrylic and cotton garment~ and
new wool is fed to a doffex or carding machine which separates
the ~ibre~ a~d tease3 them to form a 31iver or web of randomly
dispersed fibr~s, comprising 50~ acrylic and c~tto~ fibres
and 50~ wool fibre~, which i~ ~ed out of the doffer or card
onto a horizontal lapper where the ~liver or web is lapped
Oll itself until a bat of desired thickne~s i8 ob~ained. The
batt i~ then sprayed with a mixture compri~ing Rhoplex Re~in,
Aluminium Trihydra~e and Perigen pesticide.
The batt i~ then;dried in an oven, at approximately
150~C. When the batt emerges frQm the oven, it is cut into
suitable leng~h~, or rolled~in a long length, as required.
A bat ~ormad in ~he above manner, gav~ the followiny
result~:-
Sample Deacription: .
Insulatio~ batt~ compositions
Wool - noMinal - 50~ W/W
Acryli~ a~d Cotton ~ Nominal 50~ WtW
Rhoplex Re~in ~ inal 25 - 42 g/m2
~ex Rhom & Haa~ - ~hoplex HA/20)
Fl~me retardant: Alu~inium Trihydrate lex Alcoa)
Thickne~r Nominal 68mm
Fira ~ating Te t - Standard Method
Australian Btandard 1530.3.1976
TEST DESCRIPTION RESULT U~IT
EAR~Y FIRE ~ZARD PROPER~IES
, . _
OF ~TERI~LS
Ign~tabili~y Index 0 Rangs 0-20
Test De~cription Result Unit
Spread of Fl~ne Index a Range 0-10
Heat Evolved Index 0 Ranye 0-10
Smoke Developed Index 6 ~ange 0-10
S Comments on T ts
For the tes~ each specimen had a backing of 4.5mm thick
Fire ~esl~ant board and wa~ res~rained by a layer of appro~.
O.~mm diameter square wire mesh having ~a spacing of approx.
12 mm in each direction.
Mea ureme~t of Thermal Re~stence
Thickne~ (~m) 53.5
Density ~kg/m3) ~ 25
Moi3ture content (~) 9
Hot plate temperature ~C) 35.6
Cold plate temperature ~C) 15.7
Temperature differenGe (kl 19.9
Mean temperature (~C) 25.7
Thermal re~i~tance ~m2ktw) 1.34
Thermal conductivity (W/~ 0.0400
From the foregoing it will be Reen that wool, synthetic
and other natural fibrPs are bonded together to form an insu1ation
batt which may then be installed in a desired location.
Alternatively, thq b~tt may be broken down into small balls
which are blown or otherwi~e spread over the de ired location,
again to provide insulation. ~y rea~on of the inherent insulating
propertios of the wool, synthetic a~d other natural fibres,
particularly when matte~, the batt thickness is considerably
le8~ than the thick~es~ of the ~ibreglas~ batt o~ comparable
heat .in~ulation.
Thus the pres~nt inventlon provides a means of insulation
~hat avoid~ the health hazard~ of the existing insulation,
which is able to UBe ~i~carded or second-grade wool fleeces,
thereby improving the farmer~' economic retur~ on his flock,
and yet the insulatlon so produced i8 squal to ~hat ~hich it
is to replac~. In addition, discarded wool, ~ynthetic and
other natural fibre~, or wool, ~ynthetic and other n~tural
fibre garments may be ragged and used in the present invention,
again reducing the co~$ of r~w m~terials.
Although use of an oven has been described for curing
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the sprayed re~ins ~o the fibre bat~, other cwring methods
may be u~ed, including elec~ron beam irradiation.
Similarly, although the preferred chemical reagents
and resin~ have b~en de~cri~ed, other reagents and resins may
be used, provided they are compatible with each other and wi~h
the fibres~
..
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StJL':PL,E~ENTARY D:[SCL.OSIJRE
_ __ _. _ __
Applicant has described in the principal
disclosure a method of producing a bondecl fibre
insula-tion batt by ragging, -teasing and otherwise
doffering fibres of wool and/or synthetic or o-ther
natural fibres such as monoacrylic, acrylic, poly-
amide, polyes-ter or cot-ton fibres, so as -to Eorm a
sliver Witll the fibres randomly dispersed and passing
-through a lapper which causes the sliver to lap on
itself to form a mat of desired thickness. The mat is
then impregnated wi-th a resin, such as a fireproofing
resin, and preferably with a pesti.cide and a smoke
retardant~ The impregnated mat is placed in an oven
to cure the resin thus forming the insulating batt
which can be cut to desired size.
It has now been found -that by spraying the
sliver with a resin-emulsion prior to lapping ensures
-that the resin completely penetrates the material so
that the mat subsecluently formed is completely
impregnated with resin.
Aceordingly, a feature of -the invention
with whieh this supplementary disclosure is concerned
resides in providing a method of forrning a batt of
bonded fibres for use as thermal insulation, which
eomprises the steps of:
(a) ragging, teasing and doffering fibres
which include from an amoun-t from Q to 95% wool,
-together with fibres selected from the group consist-
ing of monoacrylic, acrylic, pol.yamide, polyester and
natural fibres;
(b) forming a sliver of randomly dispersed
fibres;
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(c) Eeeding the sliver onto a lapper;
(cl) oscil].a-tiny the lapper at a rate which
will deliver the sliver to a conveyor on which the
sliver is lapped onto a multi-layered mat-t;
(e) oscill.ating a spray boom in sequence
wi-th -the oscillatiny sliver to maintain -the spray
boom at the same distance from -the sliver at all
times as the sliver is delivered from the lapper;
(f) providing a second boom, which emits a
cushion of air ayainst the sliver on the side of the
sliver opposi-te the spray boom to maintain the sliver
in correc-t alignment with the conveyor;
(y) supplyiny a resin-emulsion comprisiny a
fireproofiny resin, a smoke retardant and pesticide
to the spray boom;
(h) sprayiny -the osci:llatiny sliver with
the resin emulsion so that the matt formed by -the
lapped sliver is thorouyhly impreyna-ted with the
resin-emulsion;
(i) conveyiny the impregnated matt to a
dryiny means;
(j) evapora-ting or removiny up to 80% of
-the water conten-t of the mat-t while main-taininy the
tempera-ture of the rnatt below the minimum te~perature
at which the fibre is substan-tially unimpaired by
heat;
(k) curiny -the resin content of the matt to
form a substantially rigid matt; and
(1) cu-ttiny the matt to form batts of
desired length.
As indicated above, by sprayiny the resins
onto the relatively thin sliver of dispersed fibre
immediately the sliver passes from the lapper but
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before matting ensures that -the resins comple-tely
penetrate the material so that the ma-t subsequently
formed is completely impregnated.
According -to a preferred embodiment, -the
sliver is suppor-ted on an air cushion against the
force exer-ted on the sliver when spraying the resin-
emulsion onto the sliver.
Wool and other fibres are affected by heat
and become soft and less resilien-t. Because of the
water con-tent of the resin-emulsion, up to 75% by
weigh-t, and the heat required to cure the resins, the
impregnated mat may collapse and shrink when
subjected to the external hea-ting source required to
cure the resins. The mat is therefore treated prior
to the curing step to remove up to 80% preferably
50%, of the water in a manner which obvia-tes or
reduces the heating effect on the fibres and resin.
Preferably the water removal treatment is carried ou-t
by dielectric hea-ting; for example, -the mat can be
passed between spaced plate elec-trodes of a dielec-
tric dryer and applying an A.C. voltage to -the pla-tes
at a high frequency. ~lowever, other subs-tantially
non-heating -treatments may also be used. Where a
resin-emulsion containing between 35% and 60~ water
by weight is used, the water removal treatment is
preferabLy carried out to remove approximately 50% of
wa-ter from such an emulsion.
Use of wool fibres in amoun-ts be-tween 25%
and 60% of total fibres is preferred having regard -to
the known fire-retardant properties of wool. In some
forms of batt made with soft or light fibres or
fibres which have no resiliency, if the resins used
do not add sufficient stiffness to the ba-tt it is
likely to collapse inwardly over time thus reducing
the insulating properties. Accordingly, the resins
i,r~, 9
used should preferably be selec-ted -to ensure -the hatt
retains its bulk and structura] integrity. If
desired, a stiffening agent, such as starch, resin
stiffeners or similar agents, can be added to the
batt ei-ther by incorpora-ting the stiffening agent
in-to the resin-emulsion or by separately spraying the
sliver or the mat.
The following non-limiting example further
illustrates the invention.
EXAMPLE
A mixture of ragged acrylic and cot-ton
garments and new wool is fed to a doffer, or carding
machine, which separates the fibres and teases them
to form a sliver or relatively thin web of randomly
dispersed fibres, comprising 50% acrylic and co-tton
fibres and 50% wool fibres. The sliver has a -thick-
ness of about ~ inch. The sliver is fed from the
doffer, or carding machine, onto a horizon-tal lapper
which oscillates at a predetermined rate to deliver
the sliver to a conveyor where the sliver is lapped
onto itself to build up a mat of a predetermined
thickness.
Before -the sliver leaving the lapper
engages on -the conveyor, or on -to previously lapped
material on the conveyor, it issprayed wi-th an emul-
sion of resins comprising Rhoplex Resin, Aluminium
Trihydrate and Perigen pesticide. The water content
of the emulsion is approximately 54% by weight.
A spray boom having a plurality of spray
nozzles for spraying the resin-emulsion is moun-ted
adjacent the lapper and is connec-ted -there-to by a
linkage system which maintains the boom a predeter-
mined distance from the material sliver moving from
the lapper towards the conveyor. The linkage system
causes the boom to move with the lapper but through a
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~i~' !-,;
distance related to the actual sliver movemen-t which,
because of the oscilla-ting lapper movement and the
distance between the lower end of -the lapper and -the
conveyor, is different tha-t the ac-tual lapper move-
ment.
A second boom positioned on the opposite
side of the sliver to the spray boom is fed wi-th air
to produce an air cushion to thereby balance -the
forces produced by the resin-emulsion spray and main-
tain the sliver in its correct alignment with the
conveyor.
The mat formed of the lapped sliver, which
is -thoroughly impregnated with the resin-emulsion
sprayed onto the sliver, is conveyed to a dielectric
drying station and passes be-tween spaced plate
electrodes which are electrically charged by high
frequency a.c. poten-tialO The frequency and vol-tage
applied to the plate electrodes are chosen -to
optimize drying of the ma-t with minimum hea-ting of
-the fibres. Approximately 50~ of the water content is
removed at -the drying s-ta-tion.
The mat is then conveyed -to a curing oven
hea-ted to about 150C to complete -the drying and to
cure the resins to form a relativeLy rigid but
resilient insulating mat material. When the ba-t-t
emerges from -the oven, it is cu-t in-to sui-table
leng-ths, or rolled in a long length, as required.
A batt formed in the above manner, gave
essentially -the same results as reported in -the
principal disclosure.
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