IT8348547A1 - PROCEDURE FOR THE PRODUCTION OF MINERAL, REFRACTORY, QUILTED FIBER CARPETS AND PRODUCT OBTAINED - Google Patents

Description

DOCUMENTATION

BOUND

( w ?

FEDERAL REPUBLIC OF GERMANY 1 / 0 o

_M_Il^H^M_

. (COAT OF ARMS)

CERTIFIED

11?11_h- U_11_

The company DIDIER-WERKE AG in 6200 Wiesbaden has filed a patent application entitled:

"PROCEDURE FOR THE PRODUCTION OF NEEDLE-PUNCHED CARPETS OF MINERAL FIBERS, IN PARTICULAR REFRACTORY FIBERS, AND FIBER CARPETS PRODUCED ACCORDING TO THIS PROCEDURE" dated 12 July 1982 at the German Patent Office.

The attachments constitute exact and faithful copies of the original documents of this patent application.

? The application has been granted provisionally by the German Patent Office with the Symbols D 04 H 1/4f SS

and D 04 H 1/42 of the International Patent Classification.

Monaco, add? June 22, 1983

The President of the German Patent Office Representing Signed: Wagner

(SEAL)

No. of Proceedings: P 3226 041.5

D I D I E R - W E R K E A . G.

6200 Wiesbaden

_ The _ The _ The _ H _ The ^ The _

July 12, 1982

the ii ir the ir u n the n ?? li ?i n ^

"Procedure for the production

of needled carpets of mineral fibres, in particular refractory and fibre carpets produced

according to this procedure."

the it the the i? n u ?? ?? ?? ?? _ ?? ?? ^ ?? _ ?? _ n _

The invention concerns a process for _ _

! ?

;the production of needle-punched carpets of mineral fibres, _ !in particular refractory ones, by needle-punching

a sheet of fibres provided with a sliding medium,

? - :

as well as fiber carpets produced according to this process? r

In the production of fibre mats, mineral fibres are used, especially refractory ones, which during their production process are provided with a sliding medium and respectively with a lubricant. These sliding mediums and respectively with lubricants are:

;ficants, are usually mineral oils? The production of such mineral fibres takes place according to well-known processing methods, for example according to the extraction method, the centrifugal method, the blowing method, the blowing/extraction method or the centrifugal/blowing method. These processing methods are described in more detail, for example, in Ullmann, Enzyklopaedie der Technischen Chemie, 4th Ediz?, Vol. 11, pp. 365-369.

If these glass fibres, provided with a sliding medium or lubricating products, are folded in the form of a veil of glass fibres in a disorderly manner on a belt and subsequently needled, a needled carpet of glass fibres is obtained. In this case it is necessary to subject the

such fiber mats, after the needling process "", are still subjected to heat treatment at high temperatures, for example from 300 to 600?C, so that a decrease in the tension of the fibers takes place and with this a cancellation of their elastic recovery,_ ;_ so that the needled fiber mat remains stable_ ! ' 'in shape and does not change. over time, its {shape, in particular its thickness as a consequence? ' : ? ?

'of an increase in volume due to such elastic recovery of the fibers. Another consequence of such a high-temperature heat treatment is the removal, that is, the complete burning of the sliding medium or of the lubricating product. In many cases, however, T ~? . ; 7 '

.such a complete burning of the sliding medium

!or of the lubricating product is not necessary, since..such needled carpets of mineral fibres and in particular refractory ones are normally subjected to high temperatures in their use, in

in which the sliding medium and the lubricating product respectively are eliminated in any case

From the French patent FR-PS 2462 648 it is already known to produce a complex insulating material, which is made up of several mats of fibres, which are joined together by needle-punching. As illustrated in figure 1 and in the related example of this French patent, a mat of mineral fibres is joined to a second mat of thermally stable material, for example a glass fibre fabric, by needle-punching, where between these two mats there is a

layers are inserted into the needled material, a veil of nylon fibers with a high softening point.

J_ _ Also from US patent_.US-PS .

* j !3._081_207 ? It is known to spray glass fiber mats ? 1 ! ? i with a solution of a formaldehyde resin as a binder, to obtain better adhesion of the fibers? * I

glass between them? In this: way of proceeding ?of the US patent ? is necessary, to? perform, ! following the application of the binding solution-_ ?

you, a heat treatment to activate the binder, that is, to activate the setting of this, also for the elimination of the solvent for the binder?

The aim of the present invention is to provide an improved process for the production of needle-punched fibre mats, in which it is no longer necessary to subject the needle-punched fibre mats after their production to a heat treatment at high temperatures, for example 300 to 600°C, respectively above the stretching temperature of mineral fibres, in order to achieve shape stability of the needle-punched fibre mats, i.e. to avoid a subsequent change in shape during deposition and in particular an increase in the thickness of the fibre mats.

To solve this task, the inventive process of the type described above is used, which is characterized in that after the folding of the fibre web to the desired thickness and before the needling process, a layer of mineral fibres is applied to the fibre web.

"j

synthetic, in particular polyethylene fibres, polyvinyl alcohol, polyacrylates or polyamyl

-midi?

i

? Preferred embodiments of the process according to the invention are described in more detail.

.in patent claims 2 to 9? > 1 The invention also relates to carpets of |

I

needled fibres, mineral, in particular refractory, which have been produced according to the following process:

do you agree with the invention? |

? . . . I

As mineral fibres, all the usual mineral fibres known per se can be used in the process according to the invention, in particular fibres with a high content of alumina (Al^O^), zircon, quartz, kaolin and kyanite.

.1- .. I These fibres are provided with a sliding medium and respectively with a lubricating product i

are folded in the form of a continuous ribbon in the form of a veil on a suitable base, to be subsequently subjected to the needling process. In the pr?-' [ Yield according to the invention, on this folded veil of fibres is applied, before the needling process? ?

application, a layer of synthetic fibers. This application of the synthetic fiber layer can be done, for example, by means of a current of air. Synthetic fibers used in particular are fibers made of polyethylene, polyvinyl alcohol, and polyamides. The synthetic fibers are advantageously applied in a quantity of 0.5 to 10 1/2 by weight, preferably 1.0 to 4.0 by weight, in each case related to the weight of the mineral fibers. The term "weight of the mineral fibers" used here is to be understood as meaning both the weight of the mineral fibers including the weight of the sliding medium applied above. Since the sliding piece is normally used in a quantity of 0.2 to 1.0 by weight compared to the mineral fibers, its quantity is insignificant.

In the needling process, the synthetic fibers are felted with the mineral fibers. This eliminates the need to heat-treat the finished, needled fiber mat at high temperatures to devitrify the mineral fibers and thereby eliminate their spring-back properties and the slip medium. Since the fiber mats produced according to the invention are normally subjected to heat during their use, they are also heated to a high temperature.

re, the failure to eliminate the sliding medium does not create any problems, since in this use of fibre mats the elimination of the sliding medium occurs anyway. _ _ _

In another advantageous embodiment of the process according to the invention, several fibre fleece strips are folded over one another, whereby a layer of synthetic fibre is applied to each fibre fleece strip after they have been folded before the next fibre fleece strip is folded. In this way, thicker fibre mats can be produced, for example with thicknesses of up to 150 mm. These fibre mats also have, in particular, a higher tensile strength. In another advantageous embodiment of the process according to the invention, thicker fibre mats are produced by folding the fibre fleece strip in two or more layers. ?

Layers before the needling process with the applied layer of synthetic fibers. Even with this

What is the working method for the production of carpets made of fibre?

definitely possible in thicknesses up to 150 mm.

{ | i In another advantageous form of implementation i

of the process according to the invention, subsequently to the needling process a heat treatment is carried out at a moderate temperature, for example between 100 and 200°C, i.e. a heat treatment at a temperature ur^p? higher than the softening temperature of the synthetic fibre material, whereby a fusion of the mineral fibres and the

' . . ' of synthetic fibers? Eventually, it is possible to carry out at the same time this heat treatment at moderate temperatures a compression treatment by means of which it is possible to produce carpets of ,? \

compact and possibly also already formed fibre mats, the density of which can amount to up to 400 kg/cm ? . . f ; jSuch a heat treatment with simultaneous compression treatment is advantageously carried out between appropriate forming tools? i In another preferred embodiment of the process according to the invention, a reinforcement in the form of a glass fibre fabric, a ceramic fibre fabric or a synthetic fibre fabric is inserted between individual layers of fibre webs before the needling process. In this way, it is possible to further improve particular characteristics of the fibre mats. Such reinforcements can also be used as

bottom or top outer layer?

In another preferred embodiment of the process according to the invention, in which several layers of fiber mats are used, a layer of clay or alumina is applied between the individual layers as a filler. In this way, the thickness of the fiber mats thus produced can be varied; for example, higher densities can be achieved. The amount can amount to 5 to 10 μg by weight of mineral fibers.

?

In another preferred embodiment, in addition to the synthetic fiber layer, another powdered formaldehyde resin is applied as a binder in a dry manner to the fiber veil web before j ? ^ ? . What are the advantages of the needling process? Can a formaldehyde-melamine resin, a urea formaldehyde resin and, in particular, a phenol-formaldehyde resin be used as a formaldehyde resin binder? Is this formaldehyde resin binder applied in powder form, for example by pulverizing or with the aid of a suitable sieve? Using the formaldehyde resin binder simultaneously with the synthetic fibers results in an even better bonding of the different fibers together; moreover, such a fiber mat, which has been produced with the additional use of a formaldehyde resin binder, does not have to be heated after the production process to remove any solvents. How are synthetic resin solutions used according to the state of the art? Can a colloidal silica solution be used in the same way? Another advantage of the_prj)cession according_ . . .

the invention consists in the fact that the fibre veil _

"f ,can it be produced from uncut fibres?

zi, that is, it is not necessary to use short fibres, : i 1 ;but mineral fibres cannot be used either, i.

do not cut into pieces with average lengths between 30 and 50 cm? ? ? ? "* ". ' ? . " 7 ? ! The invention is illustrated in more detail-|

?mente_with reference to the following examples;

Example 1

In this example, ceramic fibers with an Al^O content of 47$? were used. These ceramic fibers were folded into a loose fiber web with a surface weight of 1000 g/m and a width of 1320 mm after exiting the collection chamber of a spinning device and fed into a cross-folding device.

In the opposite direction of this device, a layer of loose acrylic fibers with a surface weight of 20 g is simultaneously introduced onto a feeder.

The device for cross-folding the strips was operated in such a way that a strip having a width of 1100 mm was obtained, consisting of four layers of each material, where the last lower layer of this strip is made of ceramic fibres and the last upper layer is made of acrylic fibres.

The ribbon thus produced was fed into a pre-needling machine with 4.5 stitches/cm and subsequently fed through a needle loom with 1 40 stitches/cm operating on two sides.

After cutting the edges to size, a needled fibre carpet was obtained with a thickness of 10 mm, a density of 400 kg/nr as well as a 5% glow loss and greater mechanical resistance.

Example 2

A web of loose ceramic fibres, as used in example 1, corresponding to the processing method described, was produced with a surface weight of 600 g/m and a width of 1320 mm and this web of loose fibres was fed into a device for cross-folding the strips.

This device was operated in such a way that a tape of two layers of ceramic fibers with a width of 1000 mm was obtained.

Underneath this tape, a glass fibre fabric with a width of 1200 mm was inserted, on the upper side of the fibre tape, a layer of polyamide fibres with a surface weight of 80 g/cm2 was folded, this is

1st layer covered by a glass fibre fabric with a surface weight of 300 g/m2? I{ : | : By following the working method described in example 1, a carpet of reinforced fibres was obtained

!zato with excellent properties?

j Example 3

the ?

\- Was a veil of loose mineral fibers with a surface weight of 1200 g/cm and a width of 1200 mm folded over a glass fiber mesh? On the upper side of the veil of mineral fibers were folded polyethylene fibers with a surface weight of 40 g/m^, on this in turn a glass fiber mesh? Subsequently, corresponding to the working method of example 1 -I

!? Was the needling treatment and edge cutting performed? _ _ _ The fiber mat obtained here was impregnated with a colloidal silica solution in a 1% dilution and hot compressed at a temperature of 250?C?

i In this case, a carpet of fibres with excellent properties was obtained?

1* Process for the production of needle-punched carpets of mineral fibres, in particular refractory ones, with needles of a web of fibres provided with a sliding medium, characterised in that after the web of fibres has been folded to the desired thickness and before the needling process, a layer of synthetic fibres, in particular polyethylene fibres, polyvinyl alcohol, polyacrylates or polyamolides, is applied to the web of mineral fibres.

2? Process according to claim 1, characterized in that the synthetic fibers are applied in an amount of 0.5 to 10.0% by weight, relative to the weight of the mineral fibers?

3? A method according to one of claims 1 or 2, characterised in that two or more fibre webs are folded over one another and in that a layer of synthetic fibres is applied to each fibre web before folding the next fibre web?

4? Process according to one of claims 1 or 2, characterised in that the fibre web is folded with the attached layer of synthetic fibres before the needling process in two or more layers?

5? Process according to one of the preceding claims, characterised in that . - - " j following the needling process a heat treatment is carried out, possibly with a simultaneous compression treatment?

6? A method according to one of claims 3 to 5, characterised in that a reinforcement in the form of a glass fibre fabric, a ceramic fibre fabric or a synthetic fibre fabric is inserted as the last lower layer or as the last upper layer between the individual layers?

7? Process according to one of claims 3 to 5, characterised in that a layer of clay or alumina is applied as a filler between individual layers?

- there? -

? - 8? Process according to one of claims 1 to 7, characterized in that on the fiber veil strip, in addition to the layer of synthetic fibers, a powdered formaldehyde resin is applied as a dry binder, or a colloidal silica solution? - 9? Process according to one of the preceding claims, characterized in that a veil of uncut fibers is used.

10? Carpet made of needled fibres, mineral, in particular refractory, produced according to the process of one of claims 1 to 9. _ L_

For compliant translation

/zf for oneself and for others

Enrico Toschi

or -,

re

?3

DESCRIPTION 48547 a83 accompanying a patent application for invention

from the title;

"Process for the production of carpets made of fibres

minerals, refractory, quilted and product obtained" GL CO

in the name of: DIDIER-WERKE A<.G.. o - ?l ACQUITTED CoS A proceeding is proposed for the pr?-_

production of needled carpets made of mineral fibres, in_j_

( ?)articular_r?refractory, by needle-punching a single & OQ layer of fibres provided with a sliding medium, characterised by the fact that after the folding of the veg

of fiber in the desired thickness and before the needling process, on the veil of mineral fibers is-__

a layer of synthetic fibres is applied, in particular polyethylene fibres, polyvinyl alcohol, polyacrylates or polyamides

I ? ? iO

The invention concerns a process for|

the production of needled carpets made of mineral fibres,

in particular refractory ones, by needle-punching}

a web of fibers provided with a sliding medium,j

!

as well as fibre carpets produced according to this process.

In the production of fibre mats, mineral fibres are used, especially refractory ones, which are provided with a sliding medium and a lubricant during their production process. These sliding mediums and lubricants

a. cyj ficanti, normally they are mineral oils. The production of such mineral fibres takes place according to well-known processing methods, for example according to the extraction method, the centrifugal method, the blowing method, the blowing/extraction method or!

the centrifugal/blowing method/ These processing methods are described in more detail, for example, in Ullmann, Enzyklopaedie der Technischen

i

Chemie, 4* Ediz?, Voi? 11, pages? 365-369?

If such glass fibers provided with medium;

of sliding or lubricating products ven-!

are folded^ in the form of a vel.? of fibres of ]

glass in a disorderly manner on a ribbon and then needled, you get a needled carpet of

fibers? In this case it is necessary to? submit

such carpets of fibers, after the needle-punching process

ra, still to a heat treatment at high tempe-. - . .?~ -. j

temperature, for example from 300 to 600?C, so that? have i

l

place a decrease in the tension of the fibers and j

with this? a cancellation of their elastic return,

so the needled carpet of_fibres remains stable

in shape and does not change with the passage of time. its

shape, in particular its thickness as a consequence?

of an increase in volume due to such an ejaculatory return of the fibers? Another consequence of such a

High-temperature heat treatment? Is it possible to completely burn the sliding medium or the lubricating product? In many cases, however,

or such a complete burning of the sliding medium

or the lubricating product is not necessary, from <?

-J =?3 since such needled carpets of mineral fibres! O < and in particular refractory ones are normally subjected to high temperatures in their use, in

j or in which the sliding medium and respectively the lubricating product are eliminated in any case?

From the French patent FR-PS 2 462 648 and already?

known to produce a complex insulating material, which is

made up of several fibre mats, which are

joined together by needle-punching? As illustrated in figure 1 and in the related example of this

French patent, a mat of mineral fibres vie-4

joined to a second mat of thermally stable material, for example a fibre fabric

glass, by needle punching, in which between these two

layers are inserted, added to a veil material.

_of_ nylon ^ fibers with_a_high softening pinate? _

._ Inoitre.dal breve11p americano_US-PS. 1

3 081 207 ? It is known to spray glass fiber mats ?4

-them with a solution of a formaldehyde resin such as

or binder, to obtain a better adhesion of the glass fibers or fibres between them? In this way of proceeding according to the -<t 3?r -r<-j? of the US patent it is necessary to perform,

or following the application of the binder solution, a heat treatment to activate the binder,?_

that is, to activate the setting of this, also for the elimination of the solvent for the binder? _

The aim of the present invention is to provide an improved process for the production of needle-punched carpets, in which it is no longer necessary to subject

needled fibre carpets after their production

'to a high temperature heat treatment, e- pRZNGA 1,. example from 300 to 600?C, and above respectively

of the temperature of relaxation of the mineral fibres,

in order to obtain shape stability of the needled fibre mats, i.e. to avoid a subsequent change in shape during deposition and in particular an increase in the thickness of the fibre mats?

. . .

i . :

I To solve this task, the method according to the invention of the type described is needed.

forward? which is characterized by the fact that after

the folding of the fibre web to the desired thickness and before the needling process, on the web of _

mineral fibers a layer of fibers is applied

synthetic, in particular polyethylene fibres, of

polyvinyl alcohol, polyacrylates_or polyamides 31

ZD

a? Preferred embodiments of the process according to the invention are described in more detail in claims 2 to 9?

O X

The invention also concerns carpets of j *3

-a -<t needled fibres, mineral, in particular refractory, so-called CI3 which:1,have been produced according to?the?-'procedure if?*?i

according to the invention?

As mineral fibres, all conventional mineral fibres known per se can be used in the process according to the invention, in particular fibres

high in alumina (??,,?^), zircon, quartz, kaolin and kyanite?

These fibres are provided with a sliding medium and a lubricating product respectively.

they are folded in the form of a continuous ribbon in the form

of a fleece on a suitable base, to be subsequently subjected to the needling process? In the process according to the invention, a layer of synthetic fibres is applied to this folded fibre web before the needling process. This application of the synthetic fibre layer can take place, for example, by means of an air current.

As synthetic fibres, fibres made of polyethylene, polyvinyl alcohol,

polyamide Synthetic fibres are advantageously applied in quantities of 0.5 to 10 ?? by weight, preferably 1.0 to 4.0 ?? by weight, of

referred to the weight of the mineral fibers. v The expression "weight of the mineral fibers" used here means both the weight of the 3 mineral fibers including the weight of the sliding medium applied above. Since the sliding piece is normally used in a quantity of

0.2 to 1.0 # by weight compared to mineral fibers, its quantity is insignificant.

In the needling process, the synthetic fibres are felted with the mineral fibres.

In this way it is no longer necessary to submit

the finished fiber carpet, needled, undergoes a heat treatment at high temperatures to devitrify

|the mineral fibers and thereby to eliminate its elastic return properties and to eliminate the medium

of sliding. Since the fiber carpets produced

according to the invention, during their use they are normally subjected to heat, the failure to eliminate the sliding medium

ex does not create any disturbances, since in this use C/? of the fibre carpets the elimination occurs anyway

of the sliding medium?_ _ Or "S -*x" _ In jm 'altra_ form of_ advantageous execution ??.

r-J and? of the process according to the invention, _more? tapes of

the layers of fibres are folded one on top of the other, so that there is a layer of fibre on each layer of fibre, after they have been folded.

ra, a layer of synthetic fibers is applied

before folding the next veil ribbon

of fibers? In this way it is possible to produce carpets

of thicker fibres, for example with thicknesses up to

150 mm0 These fibre carpets feature in parti-^

also provide greater tensile strength?

According to another advantageous embodiment of the process according to the invention,

thicker carpets made of fibers because

I

the fiber veil ribbon is folded in two or more?

layers before the needling process with the applied layer of synthetic fibers? Even with this

Working method The production of fiber carpets is certainly possible in thicknesses up to 150 m².

j

In another advantageous form of execution

of the process according to the invention, subsequently

in the needle-needling process a heat treatment is performed at moderate temperature, for example between_

100 and 200?C, that is, a heat treatment at a temperature slightly higher than the softening temperature of the synthetic fibre material, so

a fusion of the mineral fibres and the

synthetic fibers? If necessary, it can be done at the same time

at the same time with this heat treatment at moderate temperature a compression treatment by

which can be produced carpets of more fibres?

compact and possibly also carpets of already existing fibres?

formats, the density of which can amount to up to 400 kg/cm?

Such a heat treatment with simultaneous compression treatment is performed advantageously.

between appropriate utensils?

In another preferred form of execution? $l\ IG Mt\ ZAOH BANRDAZ?Rl &" ;..

the process according to the invention, between individual

layers of fiber veil tapes before the process

of needling an armature is placed underneath

form of glass fiber fabric, of a fabric of

ceramic fibers or a synthetic fiber fabric?

tics. In this way it is possible to further improve particular characteristics of the fi-r tapes?

bre? Such armor can also be used as

outer lower or upper layer.

In another preferred form of execution

of the process according to the invention, in which several layers of fibre veil tapes are used, between

single layers a layer of clay is applied

or alumina as a filler. In this way it is possible to adjust both special thermal properties and

the thickness of the fiber mats thus produced,

3 example? It is possible to achieve higher densities. The

3 quantities can amount from 5 to 10 $ in weight of fiber

minerals.

-a In another preferred embodiment,

*-4 Qa -in addition-.to?.the?.layer..of,.synthetic,,fibers,,2Q O is applied

another formaldehyde resin powder such as leganje

dryly on the fibre veil tape first

of the needling process0 As a resin binder

of formaldehyde? a formaldehyde-melamine resin, a urea formaldehyde resin can be used:

and in particular a phenol-formaldehyde resin. This formaldehyde resin binder is applied

in powder form, for example by pulverization or with the aid of a suitable sieve. By using the formaldehyde resin binding medium together with the synthetic fibers, one obtains

- [ -an even better union of the different fibres between the

r.P5_furthermore,_such_a_fiber_carpet,_which_has_been_produced_with_the_additional_use_of_a_formaldehyde_resin_binder,_must_not_be_reheated_after_the_production_process_to_eliminate_any_solvent

as synthetic resin solutions used according to ?-4 c in the state of the art* In the same way can a colloidal silica solution be used? ........ s Another advantage of the process according to s32? the invention consists in the fact that the fibre web -?&?--o can be produced on the basis of fibres that are not cut into pieces, i.e. the use of short fibres is not necessary, gCQ CD

but mineral fibres cannot be used either,

not cut into pieces with average lengths between 30 and 50 cm? _ The invention is illustrated in more detail with reference to the following examples:_

Example 1

In this example, ceramic fibers with an Al^O^ content of 47$ were used. These ceramic fibers were folded in the form of a veil of _

loose fibers with a surface weight of 1000 g/m

and a width of 1320 mm after its exit from the

collection chamber of a spinning device and

they are inserted into a folding device

cross-shaped

Dance opposite direction of this device?

tive? layer introduced simultaneously onto a feed belt un_velo_based on loose acrylic fibres with a surface weight of . 20 g/m 2 .

The device for the cross-folding of the

The tapes were operated in such a way that a tape having a width of 1100 mm was obtained, consisting of four layers of each material, in which

z> the last-.lower layer of this tape? constitutes- ^?

??^ ?^ to from ceramic fibers and the last upper layer'?

?3 made of acrylic fibers. -t>

The tape thus produced was introduced

in a pre-needling machine with 4.5 stitches/cm and subsequently fed through a needle loom with

40 stitches/cm operating on two sides,

After cutting the edges to size, is it?

obtained a carpet of needled fibres having a thickness

thickness of 10 mm, a density of 400 kg/m as well as a

5$ glow loss, as well as a resistance

greater mechanical strength.

Example 2

A layer of ceramic fibers was produced

loose, as used in example 1, corresponding to the processing method described therein,

with a surface weight of 600 g/m2 and a width of ?

_?

of 1320 mm and this veil of loose fibers was ih

introduced into a cross-folding device

some ribbons?

This device was operated in a

in such a way that a two-layer tape was obtained

of ceramic fibers with a width of 1000 mm?

Underneath this tape, a glass fibre fabric with a width of 1200 mm was inserted, on the upper side of the fibre tape.

Cer?miche ? a veil of polyamide fibers with a surface weight of 80 g/cm has been folded, this ?

3 was covered with a glass fibre fabric with a surface weight of 300 g/m² or fX LZi - ? By following the working method described in example 1, a reinforced fibre mat with excellent properties was obtained.

Example 3

A layer of mineral fibres has been folded

loose with a surface weight of 1200 g/cm^ and a

1200 mm width on a knitted fibre fabric

j of glass? On the upper side of the fiber veil miner?-? . ' " f

polyethylene fibres with a surface weight of 40 g/m were laid on them, and on this in turn a te-' ?.. . ~ . . "". ~~l

fiberglass mesh? Subsequently, corresponding to the working method of example 1j

Needling treatment was performed and the

cutting edges,

The fibre carpet obtained here was

impregnated with a colloidal silica solution

a 10% dilution and compressed under heat at a temperature of 250?C?

In this case, a carpet of d was obtained.

fibers with excellent properties or cL CLAIMS 35 oc 1e Process for the production of needled stages O oc mineral fibers, in particular refr?t

r-J tarie, with needles of a veil of fibers provided with half o3

CD

sliding zone, characterized by the fact that after 2E OC

?a folding??of the fibre veil in the thickness, desired OD CD

rat and before the needling process, on the veil

a layer of synthetic fibres, in particular polyethylene fibres, is applied to the mineral fibres

of polyvinyl alcohol, polyacrylates or polyamides.

2. Process according to claim

1, characterized in that the synthetic fibers

They are applied in an amount of 0.5 up to 10.0$

?-in weight, compared to the weight of mineral fibers#

3# Process according to one of claims 1 or 2, characterised in that two

or more ribbons of fibre veil are folded one after the other

on the other and from the fact that on each ribbon of veil there is

fibers a layer of synthetic fibers is applied

before folding the next veil ribbon

of fibers

4th Method according to one of claims 1 or 2, characterised in that the

with a fibre veil tape is folded, with the layer -3

O

applied, of synthetic fibers, before the c cc process.1

Needling in two or more layers?

-3 ?-4 5? Procedure according to one of the claims

-O previous cations, characterized by the fact that ir}

After the needling process, Cd CD is performed

a hot treatment, possibly with simultaneous compression treatment

_ _ 6? Process according to one of claims 3 to 5, characterised in that an infec-- -- -- - ~j is inserted as the last layer between the individual layers

upper or as a final upper layer an armour in the form of a glass fibre fabric, a textile

ceramic fiber fabric or synthetic fiber fabric?

'7? Process according to one of claims 3 to 5, characterised in that among the

single layers a layer of clay is applied

or alumina as a filler?

Claims (1)

8* .Procedure according to one of the retailers! - cations . from 1 to 7, characterized by the fact that on the ; . -- .veil-ribbon _of-fibers ?_-in-addition- to- the-layer .synthetic fibers, a resin is also applied _ _di_fermaldehyde ..in .powder as a .dry binder-I iS) jfco_.or._a.- silica _solution, .colloidal? _ i_ 32 or _9.e_Procedure._according to_one.. of the claims. oc O ? . previous cations, _characterized? -by the . fact, that... a _veil_of __fibers_is_used_not cut into pieces?' _ r-J i -O _ __ 10*_Carpet_of_. needled fibers, minerals,! _ you _ .. in particular ..refractory, ..produced.. according to, the pr? ~ or failure of_one_of_claims_1 to .9.? _ z i Bt?ift*. " ?? ???&? ? : .. "?- .. . . ? . : p. : DIDIER-WERKE A . Yes? _ _ _ UbL MA N DATERY J - 1. ?J? C?O) KC/9.2.47 n ??? and?9 4 >8 ? $-tc? Vi ss p5 O ? 'O & & Qm