DE1511058A1 - Process for the production of water-resistant corrugated cardboard by gluing at least one cover to the corrugation clamp of a strip of corrugated paper - Google Patents

Description

National Starch and Chemicsal ■ 1511058

Corporation

New York, NVY., U.S .A. '.- _

Method of making water-resistant Corrugated cardboard by gluing at least one

Cover to the ridges of a strip of corrugated paper .

The invention relates to an improved manufacture | manufacturing process for corrugated cardboard and for used, novel Binder,

The main aspect of the invention is creation a process for the production of flat, warp-free Corrugated cardboard, which has an unusually high level of water resistance. This method should also be high-performance and considerably less apparatus and require more space than the previously used methods. The invention further aims to produce water-resistant corrugated cardboard novel, fast-hardening binding agent to use, which are comparatively low in water and in heated in condition to be applied to the cardboard to allow them harden on cooling, while in contrast the previously For corrugation, binders used the heat input for formation the adhesive bond. The invention further aims the ILi rs division- of heavier as well as lighter corrugated cardboard as well so-called two- and three-wall corrugated cardboard with higher machine speed, al3 it is possible according to the previous way of working int »

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In the production of corrugated cardboard one works normally according to a continuous process in which first a cardboard web is corrugated with the help of heated corrugated rollers, then the corrugated sheets are covered with an adhesive on one side of the corrugated sheet, followed by a "lining" 3, a flat sheet of cardboard is placed in contact with the combs and gluing is effected by applying heat and pressure; the product made in this way is known as "cardboard lined on one side" because it is only provided with a cover on one surface If, however, the above-described bonding process is repeated on the ¹ free line of the corrugated sheet of cardboard lined on one side, the so-called double-sided lined cardboard is obtained, which consists of an inner, corrugated layer enclosed between two covers -.

To this extent, this experience offers the practitioner - quite a bit difficult gluing problem than the pressure that you get for the purpose of connecting the much 1st tire with the flat outer layers or covers can apply, clearly in its extent is limited.

Obviously, the application of too much or too long pressure will crush the corrugation. To deal with this difficulty, Lord, the practitioner far -solcher adhesives has used that require only brief contact with the Heizeiementen the corrugating machine in order to form the

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Strong viscose is required for a firm and permanent bond itMtser'höhurig to experience, which are very sohitell aiuös * da-dle-high cardboard production speed no longer Heating allows. .-- ■ "" -,

Originally, in the manufacture of corrugated cardboard, aqueous sodium-11icate solutions with a solids content of around 35% by weight were used as the binding agent, since this reagent has an adhesive effect due to the rapid increase in viscosity when only a little water is removed from it by the action of heat. However, its use had certain disadvantages, such as its high alkalinity, the tendency to discolour certain articles, and the extremely high brittleness of the resulting films, which "often broke when the cardboard was bent." These disadvantages, in turn, led to the use of starch mixtures, which consisted of the suspension of an adhesive portion of ungelated raw starch in a viscous carrier, which usually was accompanied by a fine aqueous dispersion of cooked starch. A total solids content of 20 ÖeW .- $ "was shown. In these approaches, the high strength was considered to be the sticky part, since it gelatinizes when exposed to heat for about 0.1 to 10 seconds and thus causes the required viscosity to increase, which in turn allows the adhesive bond Γor aqueous Trägerantfc11 other hand, is primarily used for .Heranbringung the non-cooked starch to the interface, where the täer Locally-gelatinization and liability ge ahead |... ier ^ - _(J ^ sol, ..-

Thus the above are sequentially:., I, ■ described adhesive approaches from the loss of water in the case of sodium silicate

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or dependent on in-situ gelatinization of the raw starch granules; Both known systems therefore require the absorption of large amounts of water by the cardboard and the action of heat on it, so that binding occurs. These requirements in turn lead to a number of rather serious disadvantages. This applies on most and in particular with regard to the production of cardboard clad on both sides for the compulsion to a comparatively longer drying and conditioning program to which the fresh produced cardboards have to be subjected to in order to prevent them from being discarded a few minutes after gluing has taken place. This discarding is of course caused by the moisture or, more precisely, by the bug in the moisture content one layer of the composite assembly and accompanying it Causes dimensional changes.

The tendency of the freshly glued cardboard to warp follows from the fact that normally during the Bonding process heat and excessive moisture only on one surface or cover of the double-sided covered one Soak in the cardboard. As a result, the two cardboards experience different rates of expansion when they cool down and / or contraction, especially as their moisture levels differ greatly. No special explanation is required that these different rapid expansion and / or Contraction is exacerbated by the fact that the more moist covering paperboard also adds more heat

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became. As a result, the freshly glued cardboard must be dried - or at least in terms of their moisture content, corpse Distribution to be brought. Dien happens in the way that the cardboard is stacked in such a special order that counteracted their natural tendency to distort; s'iird.

in these dry stacks the cardboard is roughly

Groups of ten or twelve placed on top of one another in such a way that "

within each group, the dry cover of the one ■ tap adjoins d'ei · the moist cover of the neighboring cardboard. The cardboard groups are then stacked on top of one another in such a way that the concave areas η of two neighboring groups face each other in order to achieve the final leveling zn . As easy to imagine, this drying and confectionery program takes up a lot of storage space in the corrugated cardboard factory and considerable. Expenditure of expensive "manual labor for da. ^C , unloading, stacking and loading and unloading of the cardboard in this .. a area. The total rate is also reduced by this", da, sr. The freshly glued ϊappan iingienugend stoif tsIiicl "and natüt'lijh cannot be printed or otherwise processed before the final conditioning, i'o v / ustisnielaweise every attempt to a verivru.uiiite pappe" to b-idruokc-n, ^rx> '/, u. lead to their crushing. AunnerOOiu, many of the today-O ₃ used- further processing autoiries fail, if, they with

ββ verkrüi.ii / iter cardboard are fed,

⁰ ^! Jin worldwide disadvantage, this time due to the heat requirement

the curling process currently used is caused, consists in the fact that they the listing of expensive and plat-

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!. ve "consumption end systems, such as the large steam generator AbcleokpaOpen-Voc'-vjärinet · and require the large hot plate sections, which .l.iit on Locally-solidification of Natriumsillkat - or ^r; täL'kal :: leb3tof The purchase and subsequent maintenance of these systems represent a high capital and labor investment.

. ', another undesirable peculiarity of the earlier

binders used in the manufacture of corrugated cardboard, which

from their high water content and their need for application of heat to the Verklebungspunkten results, is that the Gesamttiias'3hinendurchoar,: ate u ", which can be erpappe achieve, under these circumstances, and particularly in the production of SChv / something untei ¹ to V is -.n''t., the desired alah of practitioners. While you can work fairly quickly so the other stations of the corrugated board production, the machines must speed where the bonding takes place, \ duress are so greatly reduced, that the reached high temperatures, which are necessary for the expulsion of the water from the sodium silicate or the on-site gelatinization of the raw starch granules Covering cardboard is naturally a bit thicker and denser and therefore requires longer heating times.

From what has been discussed above, it is clear that the working methods currently used for corrugated cardboard manufacture and

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Binder from the point of view of performance and economy, but also of course from the quality of the finished board leave a lot to be desired.

According to the invention it has now been found that with the help of an improved mode of operation, ie. using novel binder systems, can produce corrugated cardboard that is completely flat and free from any tendency to warp. In addition, the method according to the invention works in comparison to %. the known Arbe its show with significantly higher performance, with lower costs and with higher machine speeds. In addition, it was surprisingly found that the paperboard obtained according to the invention is much stronger than the paperboard produced by known processes and, moreover, is much more water-resistant.

In short, there is what is improved by the invention Corrugated cardboard manufacturing process in which one or both sides of the corrugated or corrugated strip with the cover glued using a binder in the form of an aqueous dispersion, which when cooled a fairly considerable Able to go through an increase in viscosity. This dispersion brings one in a heated state on the wave crest on one side or both sides of the corrugated sheet and then covers the so. ■ looked at "a;, _ combs with the associated cover. The binder has the property that it solidifies immediately when it cools down and therefore does not require any polygamy "VJ poor supply results in the desired bonding. This new way of working is of course in stark contrast to the well-known

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with binders based on sodium silicate or starch working processes in which the binder consists essentially of an aqueous system that is poor in binder solids, which is applied in a comparatively cold state and itself solidified only by the addition of heat.

Accordingly, the invention consists of a method for producing water-resistant corrugated cardboard by gluing at least one cover on the crests of a corrugated paper strip, the peculiarity of the work step sequence consists in that one is on the crests of the waves on at least one surface of the Wrapping paper strip applies a binder at a higher temperature, which consists of an aqueous dispersion of an "amylose product." consists of applying at least one cover to the corrugated crests covered with adhesive and cooling the resulting corrugated cardboard, whereby when the heated binder cools down, the Forms a water-resistant adhesive bond between the cover and the corrugated strip. ■ '

Of course, numerous advantages result from the fact that the method according to the invention involves gluing the corrugated cardboard without adding a lot of water to the cardboard or adding any heat for the purpose of solidifying the binder needs to become. First and foremost, however, it is important to note that the inventive method is completely flat and warp-free corrugated cardboard · delivers and thus the complete Elimination of time and space consuming drying and conditioning measures made possible by the well-known

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Process manufactured corrugated cardboard had to be subjected to »■ The finished corrugated cardboard no longer needs to be dried and conditioned, because when using a gluing process in which the cardboard uses very little water during the actual gluing and no additional heat other than that contained in the binding agent itself receives, the warping problem is actually, completely eliminated. Polglich the practitioner can now g kostbare.Grundfläche which has been claimed by the drying up cardboards., Better utilized. In addition, the. lOperation of the time loss previously caused by the cardboard storage possible, automatic devices for loading and unloading the cardboard as well as their transfer from the production line to the others. Bedru © k> - uöd further processing stations on the one hand the overall production process and on the other hand the costly work by hand etnsuspareia * die.fois & er Eum an. and removal, the cardboard

Storage required were »" 1

- iSbeaso .bedeufeuags ^ all is with the Verder according to the invention Loss of Jedweden. Heat requirement besides that for the corrugation deformation of the file * i ^ alglloh the practitioner can nowmeiir the oil ag © under .'bet rSoht 1 lohe ä? .Saving from previous ■

s Abdeokungsvorwarfflera and .Heiss- »Baduroh occurs a substantial saving Fiat? Win capital eia »■ - ■■■ · =. ■. ^: - .: - ■■■

is also noteworthy * that mwa with '■ proceed both with severe and with

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drive lighter cardboard with a higher rate of rotation ' ^Ci \ because you can. no longer costly UTID 'spend more time consuming way heat on Verklebungsorfc needs what' previously · "; tion in the water-rich binders for the purpose weitgehender'Entwisse- ■ was inevitable and, in particular, as already mentioned, in heavy cardboard took a lot of time ■ ■ ''. '■■■

The pf for the e indungsgeraässe corrugating process suitable binder can be described as AJByloseproäÄte, the aqueous dispersions, so colloidal sols "are able to form, which in the temperature range about 88 ^east urn a viscosity of between at least about 100 and not more than about 2000 oP, but after Cooling to about 58 ⁰ C such a ψ®η is estimated to have about 1,000,000 cP »

Amylose products with these properties are used in the form of hot, aqueous dispersions for the transfer of substances. '■ used with about 15 to 60% by weight solids content. I) ispersionen but köimen 30 to 65 and iisse order to best Srge &'about 30 to% 0 öew "- ^ total solids" ie · Anglos efest st off besides ^·': sonstigeia fillers and additives, contains / em Ösat ^r e r! to resolve

to be the latter behave like Binöemittel eJtae 'solid', ie € only cooled ^ needs to © ine to foewiirken less immediate bond.

Known lent strength consists of two Fraktiönersi, one of which is called a linear and the other branches @ine © MoIeMiIs tructure has '' Only ere "to ääi ^ loose wß &

. " .Procedure for dividing the Sfc & rfee in the «lies ©

well known. «Starch orfeen

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differ in the proportions between amylose and amylopectin. , Common starches contain, for example about 1% to? 4 wt .- ^ Ämylose portion. However, certain types of starch, for example from maize, have also been genetically developed; the peculiarity of which is that one of the two factions largely predominates.

, The term used to identify an invention

"Arqylose product" thus refers both to the amylose, which Q is obtained by dividing whole starch into the amylose and amylopectin fractions, as well as to amylose-like materials, such as native starch, which as a result of genetic modification has an amylose content of at least 50% by weight. - has $. These amylose products can be of numerous different origins, for example. come from maize, wheat, potato, tapioca, sago, rice or the like; they can also be converted into . '' »So-called thin-boiling products are treated with heat and / or acids or, in order to create oxidized products, with oxidizing agents. It should be mentioned that, for the purposes of the invention, oxidized modifications are preferred to the thin-boiling ones, as the latter are likely to provide somewhat less stable adhesive products. :. For the purpose of producing a binder mixture according to the invention, the selected amylose product is normally dispersed in cold or warm water, since starches rich in amylose gelatinize only at temperatures which cannot be achieved with water at normal pressure. The amylose dispersion formed in this way must then be subjected to a boiling temperature of at least about 157 ° C. in order to work effectively according to the invention.

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One must note that hot melt systems that are par; with lower cooking temperatures by about. 120 ° C are obtained have excellent adhesive properties even _f, but only a very short

Have batch durability. Therefore, in order to achieve a sufficiently long shelf life, the amylose product dispersions should be subjected to the preferred minimum boiling temperature of about 157 ° C.
P To-the batch durability and tack properties

The practitioner can improve it even further, if desired. _; still, based on the weight of the Amy.loseproduktes contained in the dispersion, add about 0.5 to 5 fo borax or about 0.5 to 3% sodium hydroxide j. But in any case the resulting mixture after the Heissverkochen and prior to application to the Wellenkämrae the corrugated web to about 6o ° bit 96 ⁰ C and are preferably maintained at about 71 ° to 96 ⁰ C must. The low temperatures apply particularly to binders based on oxidized amylose. ' _f ,

It should be noted that when using amylose fractionated from whole starch as a binder base Measures must be taken to counteract the higher viscosity and the shorter make-up life of this type of binder. The best way to do this is to focus on one weight

^ ₃ partially fractionated amylose up to at most. 1 part by weight low

to viscous starch or dextrin or preferably an amylopectinto rich starch admixes. This achieves a viscosity

^ - decrease to around βΟΟ to 700 cP. However, the low-

^ 'viscous addition in 95 ⁰ C hot water to no more than about

25% by weight dissolve, so that the solids content is correct and higher

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Water resistance can be achieved.

The gluing process according to the invention can be carried out with the systems previously used for the production of corrugated cardboard, the only changes being, on the one hand, the omission of the heating system that is no longer required, ie. boilers, Abdeckungsvorwärmer, hot plates - etc, and on the other hand, in the installation of heating coils in the binder pan and a heater are made for the binder applicator roll to the ™ binder before application to the crests of the corrugated web to about 70 ° to 95 ⁰ C hold. .

The actual application of the binding agent to these corrugated crests can be carried out with the aid of the application rollers used in most corrugated cardboard machines, but if desired also by other methods, which possibly enable a more economical distribution of the binding agent. After gluing, the corrugated sheet can immediately be brought into contact with the covering cardboard, which of course does not need to be preheated because of the gluing . a is done by simply cooling the binder to about 32 ° to 5 ^ ° C. This cooling triggers a considerable increase in viscosity and thus an immediate solidification again. As a result, one only needs to apply the cover cardboard tightly to the binder-covered, corrugated web with the application of appropriate pressure and thereby achieve their mutual gluing within 0.1 to 1 second or even faster, if one by applying cooling plates to the cover cardboard the cooling and the resulting binder solidification are accelerated.

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The inventive method can be used for the production can be used for corrugated cardboard that is only lined on one side and on both sides. You can do it with any ■ known methods or binders combine by, for example, the first corrugated cardboard cover with the help of a in-situ-gelatinizing starch binder and the usual Apparatus for corrugated cardboard lined on one side and then the second cover according to the method of the invention and using the usual apparatus for corrugated cardboard lined on both sides. This embodiment is for the Practitioners are of particular interest because it is well known that when the second cover is applied using adhesive methods that have been customary up to now numerous problems occur while the application of the first cover is comparatively uncomplicated is.

The excellent advantage of the inventive hergefc corrugated cardboard is its exceptionally high water resistance, which they immerse in water for 24 hours and can hold out even longer. The novel 'corrugated cardboard tolerates So not only the moisture that occurs during normal use, but also excess and fluctuations in moisture> with which one has to calculate in the open air.

In the following examples, in which part details, unless otherwise stated, based on weight, the invention is explained in more detail.

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example 1

This example shows the use of the invention Process in addition to novel binders for the production of both one-sided and two-sided cladding Corrugated cardboard. ,

'A binder approach from 8o parts .Water and 20 parts was carried Dauerdruckkochung at 121 ⁰ C ainylosereicher ^f Maisstärlce (liiit 70 wt ?; amylose) prepared by the cooked product filled into the binder pan of the well apparatus and held in it to 88 ⁰ C . While this product was found to be a useful binder, it was found to have been found _; only extremely short shelf life, as it gelled so strongly in less than 30 minutes that the corrugation process is interrupted .

Corresponding attempts were made with the same approach, but with a gradual increase in the continuous cooking temperature around 5 * 6 ° C and showed that only from one

J high temperature of 157 ° C from a batch stability achieved ^

which allowed uninterrupted operation. By further temperature increase they came to the optimum Koehteinperaturbereich con 157 ° to 169 ⁰ C, which one uiit with simultaneous observance of Bindemxttelarbeitstemperatur Q to about 71 ° C ⁰ 96 bi.s derai't a good stability or neck support -barite i "; achieved that you can use the Zusainmenverbindmasohine in

«Ο Work continuously and without having to take breaks from cleaning

can leave. But if the binder is colder than about ο. ~. - ■

Q 6θ ° α leaves the animal, then it "gels" or solidifies very much 'ε ".line 11, and -isn :: usi3 stop with öe-.Susa seed sticking process .

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The binder mixture, which was kept at 88 ⁰ G and a viscosity of 250 cP after pressure cooking, was divided into two portions which, depending on the arfindurigs regulation, were used to produce one-sided or Corrugated cardboard clad on both sides was used. The corrugated cardboard lined on one side was produced with the help of a conventional sinfachabdeckmaschine with hot rollers for the web corrugation, while for the production of the two-sided lined corrugated cardboard a conventional double covering machine was used, which was equipped with cooling plates to accelerate the gluing process. Both types of corrugated cardboard were produced with excellent bonding at throughput speeds of around βθ m / min.

The above method of operation was fundamentally under otherwise The same conditions are repeated with the modification that the basic binding agent is one of potato starch ionized ainyloas was used according to the following recipe: j.

Amylose I5 parts

Amylopectin (by means of HOL on the hand

• fluid it ät 85 acid ino-- ". ■

differentiated) 10 parts

Water 100 parts

After boiling at 163 ⁰ C the binder mixture showed a viscosity of 450 cP, and a total solids content of 2C by weight '. When used in practice in the manner described above, it exhibited adhesive properties that were generally comparable with the approach described above.

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; . : ^{; :} Example 2 . . '■'

This example illustrates the high grade water - resistance of corrugated cardboard, which is made using the new, binder systems according to the invention was prepared.

The binder approach used for this consisted of:

high-arylose corn starch

(20 wt -.% amylose) 20 parts

- j _: water ^: - 80 "■

■ The water resistance of the cardboard gluing was determined in the following way:

The cardboard was first immersed for 24 hours in 22 ⁰ Ω warm water and then as follows for peeling and fiber tear.

Layer separation : The edges of the corrugated cardboard were bent with thumb pressure - to such an extent that it could just overcome the surface tension of the water, whereby the individual layers of lilac should not separate more than 6 mm from the edge of the sample. ■ f

Fiber tearing : In the previous layer separation test, tearing the individual fiber boards or the inside of the fiber was not considered a layer separation. After physical Schichtauftrennung but samples of Gesamtverklebungsfläohe Fas ^ ^ March rreissung existed were again tested and although it> on welchein share. The result was _| then expressed as percent fiber tear.

The hiifc the inventive Bindemittelsystern corrugated board prepared 'was then aged for and eingetälioht in 22 ° C water viarmes 2 ^J f hours. Up to ■ ' % ® \ s | tirtd! Göip Tauohzeiti "-zf ^ igibe" .- ,. ^{v Λ} >: | ö983ff / 0070 ⁱ - ^{;: ^:} - ^ - ^

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there is no voluntary class separation. There was also no delamination during bending and kinking. Then the individual layers were separated by hand, resulting in such deep fiber tearing that the layers were completely destroyed, so the fiber tearing was 100 % .

So the results of this example clearly prove _ the superior water resistance of bondings and corrugations.

paperboard as a whole, if they are made with the help of the novel Binder systems are produced.

Example 3

This example explains the production of a binder system according to the invention, this time with a modified one Recipe and the high level of water resistance with it manufactured corrugated cardboard bonds.

15 parts of high-amylose corn starch (with 55 wt .- $ amylose) were white, with the addition of 5 parts of commercial ^ to 25% soluble dextrin and - on Dextringewicht based - 10 fa suspended in Borax 8o parts of water. This Bohansatz with a viscosity of 270 cP and 23 wt ..- ^ total ^{solids content was pressure cooked at 157 0} C and then for the production of corrugated cardboard using cold plates instead of hot plates

Q. Throughput total? used by oil m / min, In Oil & medium pan0n'1nr4fe kainö trace of pre-thickening, and the Wellpappenheri? ^ | 3, u'o4 ran for about 2 hours - trouble-free. During the WeliUttAo process this BinöetnifcfcelA *

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"» - '* ■ - ■ - yni ^ v ^ i ι «-win» λ »IM» «■; -

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approach, a viscosity of 300 cP at 88 ° C and 120,000 cP at 38 ⁰ C. The corrugated board prepared with it showed after 24 stUndigem watering no layer separation and yielded 75 $> strength Faserzerrelssung with forced Schichtauftrennung. * Example 4

This example explains the production of another, novel binder approach and its use in the multi-board production according to the method according to the invention and also the water resistance of the corrugated cardboard bonds produced with it.

In this example, 20 parts of high-amylose corn starch (with 70 wt .- ^ amylose content), 10 parts of a dUnnkochenden to 100 parts by weight? I from ^r Amj lopektin existing stae ^ rle, which was acid-modified at the HändeIsfluidität 85 by means of HCl, and 10 parts of ^m on dispersed in 60 ^r reilen Viasser. The aim of adding amylopectin and clay was to increase the solids content in the finished starch dispersion.

This suspension was druckverkocht at 163 ⁰ C, viobei they aufviies a Gesanitfeststoffgehalt of 37.2 wt .- ^, held in the binder pan of the multi lungs mas chine entered and in it to more than 83 ° 0 and a ■ .Viskosität of 350 op. It was used to glue both heavy and light corrugated cardboard without steam application at the connection station at throughput speeds VOiT 107 m / min each. After 24 hours of watering, both showed no separation of the layers and, when the layers were forced to separate, resulted in tears in the skin.

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The above summarized results clearly show that one can use the binder systems according to the invention can produce faster when the solids content is increased without suffering any loss of water resistance.

Example 5

This example illustrates the preparation of yet another binder formulation according to the invention, this time an oxidized, amylose-rich corn starch as a binding agent is used, and also the high level of water resistance of the corrugated cardboard bonds made with it.

In βθ Wassersuspendiert parts - in this example, 40 parts of an oxidized by treatment with sodium hypochlorite, high amylose corn starch (amylose with 55% wt.). This starch dispersion was druckverkocht at 157 ° C to a total solids content of 38.5 wt .- ^ is input to the binder of the pan and held WeIlungsmaschine 88 ⁰ C and a viscosity of 290 cP in its over. With it both heavy and light corrugated at throughput speeds of each 107 m / min glued .. was without steam supply to the hot plates of the connecting station Both showed after 24 stundigem waters no layer separation and resulted in forced Schichtauftrennung 100 fo owned Faserzerreissung.

In summary, then, the invention provides the practitioner with novel binder approaches for use in a improved manufacturing process for corrugated board, which is characterized by outstanding water resistance.

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Claims (3)

Patent claims \ 1)) \ rexperienced in the production of water resistant Corrugated cardboard by gluing at least one cover to the Wave crests of a strip of corrugated paper, characterized in that the wave crests on at least one surface of the Corrugated paper strip applies a binder at a higher temperature, which consists of an aqueous dispersion of an amylose ■ product consists, on the corrugated combs covered with adhesive at least one cover and the resulting corrugated cardboard cools down, while cooling down the heated binder the water-resistant adhesive connection between the cover and the corrugated strip trains. . ■■■ ' 2) The method according to claim 1, characterized in that the amylose product is boiled at at least 157 ° C and kept at at least 60 ⁰ O during application to the corrugated paper strip. . . .. 3) The method according to claim 1 or 2, characterized in that "an aqueous dispersion of the amylose product is used which - based on dispersion weight - has about 15 to 60 f and of estimated about 100,000 cP according to Aokühluap; to about 38 ⁰ O, Ί) Method according to one of claims 1 to 3, characterized in that an oxidized amylose product is used. 0 9 838/0070 BATH ORIGINAL