EP0664357B1 - Water resistant and repulpable compact material from broken cellulose and process of preparation thereof - Google Patents

Abstract

A novel compact, water-resistant material (I), based on ground cellulosic material, is repulpable and contains: (A) an organic binder selected from starch (or derivs.), flour, proteins, starch mfr. by-products, cellulose (or derivs.), hemicellulose (or derivs.) and mixts.; and (B) an organosilicon or fluorinated acrylic copolymer hydrophobic agent to provide water resistance.

Description

The subject of the invention is a compact material "repulpable" and water resistant, obtained from crushed cellulosic materials.

It also relates to a process for preparing this material.

By the expression "compact material" is meant, at sense of the present invention, a material having a sufficient cohesion and mechanical strength to be able to be used for example in the industry of furniture, in the construction industry (for example example for the manufacture of panels or partitions), in the horticultural industry (e.g. for manufacturing trays for potted plants) or in the packaging (for example for manufacturing pallets, supporting elements, shims, elements spacing ...).

By the expression "plumpable" is meant, always within the meaning of the present invention, the property which the can be used directly after a possible grinding, as a raw material in manufacturing paper, without requiring any sorting or physical, mechanical, or physico-chemical separation, and without generate waste other than waste normally produced during the production of paper. Such a material repulpable can therefore be introduced directly at the pulp from the paper machine, without sorting operation prior.

We know that many activities are consumers of wood or wood-based materials. he this is particularly so in the manufacture and use wood or particle board panels, pallets, wooden presentation trays, boards, holds, etc ... A major problem, and that goes elsewhere growing, lies in the difficulty of valuing wood waste generated by these activities. So if we take wooden pallets for example, commonly used in industry and in distribution, it it appears that it is more and more difficult to recover them and recover them after use. Their recovery is indeed difficult, in particular because of their relationship high volume / weight and due to the need to remove the nails used in their manufacture. In addition, wood as well recovered can hardly be used for anything other than destruction by fire.

There is also a major problem disposal, and a fortiori recovery, waste paper and cardboard. In Germany, for example, the incineration of old paper was banned. It is indeed polluting and causes fouling of the boilers used for their combustion.

In order to try to reduce the consumption of this an eminently ecological resource of wood, and in order to try to recover large quantities of waste of paper and cardboard generated by the various activities mentioned above, it has already been offered to make, from old paper or cardboard, insulating materials and building materials analogous to wood.

But the materials thus produced are not satisfactory.

On the one hand indeed, they do not always present the water resistance that is necessary for some uses.

And on the other hand and above all, they cannot be recycled directly into the manufacturing circuit of a paper machine. Even when performing sorting operations recycling them can therefore cause serious difficulties in making paper or in subsequent use of paper (problems printability, or problems sticking the groove in the case of the manufacture of corrugated cardboard, by example). Huge losses in paper production are thus incurred in case of pollution of the circuit by said materials. Various treatments (skimming, treatments minimize these risks, but they are very expensive and not necessarily entirely reliable.

The Applicant Company, after becoming aware of these difficulties, had the merit of completely redefining the technical problem and establish that a solution really satisfactory could only be found at the condition to manufacture, using cellulosic materials such as waste from old paper and cardboard, compact materials which, while being resistant to water, offered a particular property, namely a total and entire "repulpability".

Besides this complete redefinition of the problem technique, the invention consists in selecting, for the manufacture of the compact materials according to the invention, products which prove compatible with this property of total repulpability. In particular, in accordance with the invention, binding agents are selected on the one hand, and agents capable of imparting some resistance to water on the other hand, which are perfectly compatible with said repulpability property.

The presence of binding agents is necessary in order to allow the production of compact materials with a sufficient strength and cohesion, in particular high compressive and flexural strengths.

The presence of agents capable of imparting some water resistance is desirable because the compact materials targeted by the invention can be used in very humid atmospheres, or be placed in contact with damp soil.

Various types of binders, possibly associated with agents capable of imparting some resistance to water, have already been used or offered in art for the manufacture of compact materials of the kind of those targeted by the present invention.

So binders such as alcohols polyvinyl and their derivatives, celluloses and their derivatives, lignosulfonates, starches and their derivatives, alkali silicates, clays, tars, pitches and bitumens have already been offered.

It was more particularly proposed to have use, as a binding agent, of starch which, used alone or mixed with other binders, as taught for example the patents EP 4 135 330, DE 4 141 864 and DE 3,627,255 has many advantages.

However, and this is a major drawback, even prohibitive in most applications, materials linked together with starch, just like elsewhere those linked with bentonite, have a sensitivity extremely marked with water, making it impossible to storage in the open air and even their storage in a humid atmosphere.

It has therefore been proposed, to try to remedy this essential drawback of associating starch with pitch, asphalt or bitumen, or even insolubilize starch with urea-formaldehyde, phenol-formaldehyde resins, melamine-formaldehyde, ketone-formaldehyde or mixtures thereof, or also to associate starch with plastics or hot melt resins.

None of these solutions are found satisfactory because none provides, in economically and ecologically acceptable conditions, compact materials based on finely cellulosic material crushed with characteristics simultaneously high mechanical properties, sufficient water resistance, and above all total repulpability.

Indeed, all the solutions proposed up to present used binders and / or adjuvants which make the compact materials obtained non-repulpable and these cannot therefore be easily recycled without pre-sorting operation, and without creating any problem for the subsequent production or use of paper and / or cardboard.

Due to the adequate reformulation of the problem technical and thanks to the selection of certain binding agents and certain water resistance agents, the Company The plaintiff therefore had the merit of remedying the disadvantages of the prior art and offer a solution entirely advantageous to the problems raised by the consumption of wood or wood derivatives and by the recovery and recovery of wood waste, paper or cardboard, allowing the manufacture of compact, water-resistant and repulpable materials, based on cellulosic materials.

• d'une part une quantité efficace d'un liant organique choisi dans le groupe comprenant les amidons, les dérivés d'amidon, les farines, les protéines, les sous-produits d'amidonnerie et de féculerie, les celluloses et leurs dérivés, les hémicelluloses et leurs dérivés, ainsi que les mélanges de ces produits et,
• d'autre part une quantité efficace d'un agent de résistance à l'eau choisi parmi les agents hydrofugeants organosiliciques et les copolymères acryliques fluorés.

In accordance with the invention, the materials in question are characterized in that they comprise:

• on the one hand, an effective amount of an organic binder chosen from the group comprising starches, starch derivatives, flours, proteins, starch and starch by-products, celluloses and their derivatives, hemicelluloses and their derivatives, as well as mixtures of these products and,
• on the other hand, an effective amount of a water resistance agent chosen from organosilicon waterproofing agents and fluorinated acrylic copolymers.

The effective quantity is the quantity sufficient to achieve the desired effect.

According to an advantageous embodiment of the material compact according to the invention, the organic binder is chosen from starches, starch derivatives, and / or starch or starch by-products.

• en ce qui concerne l'amidon, les amidons de toute origine, naturels ou hybrides, provenant par exemple de la pomme de terre, du manioc, du maïs, du maïs cireux, du maïs à haute teneur en amylose, du blé et des coupes qui peuvent en être faites, de l'orge et de sorgho,
• en ce qui concerne le dérivé d'amidon, les amidons modifiés par voie physique et/ou chimique.

When the organic binder forming part of the compact material in accordance with the invention is a starch or a starch derivative, the following terms are used:

• with regard to starch, starches of all origins, natural or hybrid, originating for example from potatoes, cassava, maize, waxy maize, maize with a high amylose content, wheat and cuts that can be made of it, barley and sorghum,
• as regards the starch derivative, the starches modified physically and / or chemically.

Advantageously, the organic binder is chosen among native starches, possibly made soluble in cold water using physical treatment of baking-extrusion and / or gelatinization on a drum.

When the organic binder entering the constitution of the compact material according to the invention is chosen from the by-products of starch and starch, preferably waste water is used deprotein from a starch protein factory, particular potato starch. Water deproteinized waste in question can be obtained in various ways, and in particular to result from potato starch effluent treatment known to those skilled in the art as "water from vegetation "or" red water ", the general principle of which production is described in French patent FR 2 256 727.

dans laquelle R et R₁, qui peuvent être identiques ou différents l'un de l'autre sont de l'hydrogène ou des radicaux organiques choisis dans le groupe comprenant les radicaux méthyle, alcoyle, fluoroalcoyle, phényle éventuellement substitué, vinyle ou leurs dérivés chlorés, alcoxy, alcoylamino, ledit composé étant avantageusement choisi dans le groupe comprenant les huiles silicones non réactives, les résines silicones, les huiles silicones réactives notamment hydroxylées, alcoylées, arylées, hydroalcoylées, hydroarylées ainsi que les mélanges de ces produits et les émulsions qui peuvent être préparées à partir de ces produits.According to another advantageous embodiment of the compact material according to the invention, the water-resistance agent is chosen from organosilicon water-repellants, the structural unit of which corresponds to the formula:

in which R and R ₁ , which may be the same or different from each other, are hydrogen or organic radicals chosen from the group comprising methyl, alkyl, fluoroalkyl, optionally substituted phenyl, vinyl or their derivatives chlorinated, alkoxy, alkyllamino, said compound being advantageously chosen from the group comprising non-reactive silicone oils, silicone resins, reactive silicone oils, especially hydroxylated, alkylated, arylated, hydroalkylated, hydroarylated as well as mixtures of these products and the emulsions which can be prepared from these products.

dans laquelle

• R₂ est un groupement alcoyle (C₁-C₁₀), alkényle (C₁-C₁₀) ou aryle (C₆-C₁₀)
• X est un atome de métal alcalin ou alcalino-terreux et
• 1 ≤ n ≤ 10

le siliconate de potassium étant particulièrement préféré.According to a particularly advantageous embodiment of the compact material according to the invention, the organosilicon water-repellent agent is chosen from the group of siliconates of general formula:

in which

• R ₂ is an alkyl group (C ₁ -C ₁₀ ), alkenyl (C ₁ -C ₁₀ ) or aryl (C ₆ -C ₁₀ )
• X is an alkali or alkaline earth metal atom and
• 1 ≤ n ≤ 10

potassium siliconate being particularly preferred.

a) 35 à 98 %, de préférence 69 à 93 %, d'un ou plusieurs monomères polyfluorés de formule générale :

dans laquelle Rf représente un radical perfluoro-alkyle à chaíne droite ou ramifiée, contenant 2 à 20 atomes de carbone, de préférence 4 à 16 atomes de carbone, Q représente un atome d'oxygène ou de soufre, B représente un enchaínement bivalent lié à Q par un carbone et pouvant comporter un ou plusieurs atomes d'oxygène, de soufre et/ou d'azote, l'un des symboles R représente un atome d'hydrogène et l'autre un atome d'hydrogène ou un radical alkyle contenant 1 à 4 atomes de carbone ;

b) 1 à 15 %, de préférence 5 à 11 % et surtout 7 à 10 %, d'un ou plusieurs monomères de formule générale :

dans laquelle B' représente un radical alkylène linéaire ou ramifié, contenant 1 à 4 atomes de carbone, R' représente un atome d'hydrogène ou un radical alkyle contenant 1 à 4 atomes de carbone, R₁ représente un radical alkyle contenant 1 à 18 atomes de carbone, hydroxyéthyle ou benzyle, R₂ représente un atome d'hydrogène ou un radical alkyle contenant 1 à 18 atomes de carbone, hydroxyéthyle ou benzyle ou R₁ et R₂ ensemble avec l'atome d'azote forment un radical morpholino, pipéridino ou pyrrolidinyle-1 ;

c) 1 à 50 %, de préférence 2 à 20 %, d'un ou plusieurs monomères de formule générale

dans laquelle R₃, R'₃, R₄ et R₅ sont identiques ou différents et représentent chacun un atome d'hydrogène ou un radical alkyle contenant 1 à 4 atomes de carbone ; et éventuellement

d) jusqu'à 10%, de préférence moins de 5 %, d'un monomère quelconque autre que les monomères de formules (I), (II) et (III).

According to another embodiment of the compact material according to the invention, the water resistance agent is chosen from fluorinated copolymers as described in European patent 0 034 527. These copolymers, optionally salified or quaternized, comprise in weight :

a) 35 to 98%, preferably 69 to 93%, of one or more polyfluorinated monomers of general formula:

in which Rf represents a perfluoroalkyl radical with a straight or branched chain, containing 2 to 20 carbon atoms, preferably 4 to 16 carbon atoms, Q represents an oxygen or sulfur atom, B represents a divalent chain linked to Q by a carbon and possibly comprising one or more oxygen, sulfur and / or nitrogen atoms, one of the symbols R represents a hydrogen atom and the other a hydrogen atom or an alkyl radical containing 1 to 4 carbon atoms;

b) 1 to 15%, preferably 5 to 11% and especially 7 to 10%, of one or more monomers of general formula:

in which B 'represents a linear or branched alkylene radical containing 1 to 4 carbon atoms, R' represents a hydrogen atom or an alkyl radical containing 1 to 4 carbon atoms, R ₁ represents an alkyl radical containing 1 to 18 carbon, hydroxyethyl or benzyl atoms, R ₂ represents a hydrogen atom or an alkyl radical containing 1 to 18 carbon, hydroxyethyl or benzyl atoms or R ₁ and R ₂ together with the nitrogen atom form a morpholino radical, piperidino or pyrrolidinyl-1;

c) 1 to 50%, preferably 2 to 20%, of one or more monomers of general formula

wherein R ₃ , R ' ₃ , R ₄ and R ₅ are the same or different and each represents a hydrogen atom or an alkyl radical containing 1 to 4 carbon atoms; and eventually

d) up to 10%, preferably less than 5%, of any monomer other than the monomers of formulas (I), (II) and (III).

According to a particularly embodiment advantageous of the compact material according to the invention, the water-repellent agent is chosen from copolymers fluorinated products such as those sold by ELF ATOCHEM under the name FORAPERLE, and in particular under the name FORAPERLE 321.

• une proportion de 0,5 à 40 %, de préférence de 1 à 25 %, et plus préférentiellement encore de 2 à 20 % en poids de liant organique,
• une proportion de 0,005 à 10 %, de préférence de 0,025 à 6 %, et plus préférentiellement encore de 0,05 à 4 % en poids d'agent hydrofugeant.

Relative to the weight of milled cellulosic materials forming part of the compact material according to the invention, the latter advantageously comprises:

• a proportion of 0.5 to 40%, preferably from 1 to 25%, and more preferably still from 2 to 20% by weight of organic binder,
• a proportion of 0.005 to 10%, preferably from 0.025 to 6%, and more preferably still from 0.05 to 4% by weight of water-repellent agent.

The proportion of water repellent is, ultimately, calculated to give the compact material a hold satisfactory water, knowing that the main objective by the invention is to ensure the repulpability of the material got.

The compact material according to the invention can possibly include other constituents such as by example of hardening agents, present in a proportion from 0.5 to 25%, preferably from 1 to 5% by weight relative to by weight of crushed cellulosic materials.

The curing agents in question may be selected from the group of alkaline agents, plus particularly in the group of hydroxides and oxides of alkali or alkaline earth metals, or in the group of salts of strong bases or weak bases, and in particular among carbonates of alkali or alkaline earth metals. The preferred hardening agent is lime hydrated.

The compact material according to the invention can also include other constituents such as, for example, bactericides, fungicides, rat poisons ...

• que l'on sélectionne un matériau cellulosique broyé, un liant organique du groupe précédemment défini, un agent hydrofugeant organosilicique ou un copolymère fluoré, et éventuellement un agent durcisseur,
• que l'on mélange l'agent hydrofugeant avec soit le matériau cellulosique, soit le liant organique, soit avec l'un et l'autre de ces produits ou leur mélange,
• et que l'on soumet le mélange ainsi obtenu à un traitement de mise en forme, par exemple par pression, compression, agglomération, compactage ou extrusion.

The process according to the invention for preparing the compact material according to the invention is characterized by the fact:

• that a ground cellulose material, an organic binder from the group defined above, an organosilicon water repellant or a fluorinated copolymer, and possibly a hardening agent, are selected,
• that the water-repellent agent is mixed with either the cellulosic material or the organic binder, or with both of these products or their mixture,
• and that the mixture thus obtained is subjected to a shaping treatment, for example by pressure, compression, agglomeration, compacting or extrusion.

According to this process, the water-repellent agent is therefore distributed in the heart of the compact material, which allows to obtain excellent water resistance. Eventually, this water resistance can be further enhanced by applying an additional amount of water repellent on the surface of the compact material already formed, by any known technique, for example by coating, impregnation, immersion, spraying or brushing.

• que l'on sélectionne un matériau cellulosique finement broyé, un liant organique du groupe précédemment défini, et éventuellement un agent durcisseur,
• que l'on mélange le matériau cellulosique, le liant organique et éventuellement le durcisseur,
• que l'on soumet le mélange ainsi obtenu à une mise en forme, par exemple par pression, compression, agglomération, compactage, ou extrusion.
• que l'on applique une quantité choisie d'agent hydrofugeant en surface du matériau compact ainsi obtenu, par exemple par enduction, imprégnation, immersion, pulvérisation ou brossage.

However, for certain uses, it is sufficient to apply only the water-repellent agent to the compact material already formed and the process according to the invention is then characterized by the fact:

• that a finely ground cellulosic material is selected, an organic binder from the group defined above, and optionally a hardening agent,
• that the cellulosic material, the organic binder and possibly the hardener are mixed,
• that the mixture thus obtained is subjected to shaping, for example by pressure, compression, agglomeration, compaction, or extrusion.
• that a selected quantity of water-repellent agent is applied to the surface of the compact material thus obtained, for example by coating, impregnation, immersion, spraying or brushing.

According to another embodiment, a composition of matter comprising the organic binder and minus part of the water repellent. We make a intimate blend of finely ground cellulosic materials and this composition of matter, and we submit this mixture to a shaping treatment, the possible part of water-repellent agent not included in the composition of material being for example applied to the product resulting from shaping treatment.

The nature and proportions of the constituents are selected in such a way that the compact material obtained has characteristics of mechanical resistance, water resistance and repulpability indicated previously.

According to an advantageous embodiment of the method in accordance with the invention, the compact material obtained is subjected at the end of the shaping treatment to a treatment steaming under generally temperature conditions between about 80-100 ° C and about 200-220 ° C. The duration of this parboiling treatment depends on the temperature, but is usually between 15 minutes and 5 hours, preferably between 30 minutes and 3 hours.

When the waterproofing agent used is a siliconate and in particular a potassium siliconate, this parboiling treatment is optional and does not constitute essential step of the process which is the subject of the invention. Unlike the different techniques of the prior art, compact materials according to the present invention present in this case, by simple treatment with ambient temperature, the required physical characteristics and in particular a high mechanical resistance; steaming does not only accelerates the drying of compact materials obtained.

In the case of the use of another agent water repellent and especially in the case of the use of fluorinated copolymers, it is generally preferable to subject the compact material obtained at the end of the treatment formatting in the above steaming treatment.

The compact material according to the invention has variable mechanical characteristics depending on the pressure which is exercised during the shaping treatment.

Thus, if a low pressure is exerted, we obtains a "mattress" made of cellulosic materials which is flexible and elastic. Such a material may be suitable for example in calibration operations or as a product anti-shock or anti-vibration.

Conversely, if strong pressure is exerted, the compact material obtained has resistance to very high bending, tensile and compression and can be advantageously used as a cushioning material, or as a reel core. He can also serve as material for making pallets biodegradable and plumpable. This is an advantage essential of the present invention.

Another essential advantage of the present invention is that by selecting binding agents and water repellents including contact with food food is allowed, we can get materials compacts that can be used for example as cushioning materials in product packaging food or as a packing material for packaging of toys, for example.

The invention can be understood even better. using the examples which follow and which relate to advantageous embodiments.

EXAMPLE 1

In a mixer of the Robot coupe type, 1000 g of crushed waste paper having a particle size of less than 1 cm is introduced on the one hand, and 100 g of AGGLOFROID ^R 009 (pregelatinized starch sold by the company ROQUETTE FRERES) on the other hand - (62-LESTREM) and 250 g of drinking water containing 30 g of potassium siliconate The mixture obtained is then kneaded for 5 minutes, then it is agglomerated by molding in the form of square panels 6 cm wide and 1 cm high, at a pressure of 3432 10 ⁴ pascals The test pieces thus obtained have sufficient green cohesion to undergo transport.

• en flexion :
  • à vert   : 500 N
  • après 48h de séchage à température ambiante   : 1000 N
  • après 2h de séchage à 100°C   : 1200 N
• compression sur champs :
  • après 72h de séchage à température ambiante   : 4000 N

The resistance of these test pieces, determined using a PERRIER brand compression tester, has the following values:

• in flexion:
  • green: 500 N
  • after 48 hours of drying at room temperature: 1000 N
  • after 2 hours of drying at 100 ° C: 1200 N
• compression on fields:
  • after 72 hours of drying at room temperature: 4000 N

These test pieces are then placed in an atmosphere humid, at 100% relative humidity and at 25 ° C. He is not observed disintegration, even after several weeks. The mechanical strength of test pieces remains unchanged after this stay in wet storage. The interior of the test specimens does shows no trace of moisture.

On the other hand, if one of these plates is placed in a beaker of cold water with gentle stirring for 4 at 5 a.m., we see that it starts to swell slightly then to disintegrate. After 6 to 7 hours, we thus obtain a coarse paper, which can be directly worked in a stationery pulper.

• en flexion :
  • à vert   : 100 N
  • après 48h de séchage à température ambiante   : 150 N
  • après 1/2h de séchage à 80°C   : 150 N
• en compression sur champs :
  • après 72h de séchage à température ambiante   : 800 N

If paper waste of the same composition is compacted under the same conditions but in the absence of any binder, samples are obtained having the following mechanical strengths, always determined using the PERRIER compression tester:

• in flexion:
  • green: 100 N
  • after 48 hours of drying at room temperature: 150 N
  • after 1/2 hour of drying at 80 ° C: 150 N
• in compression on fields:
  • after 72 hours of drying at room temperature: 800 N

These test pieces then being placed in an atmosphere humid, at 100% relative humidity and at 25 ° C, swelling of the platelets after 24 hours. After 96h, the material no longer has any cohesion.

• en flexion :
  • à vert   : 500 N
  • après 48h de séchage à température ambiante   : 1000 N
  • après 2h de séchage à 100°C   : 1200 N
• en compression sur champs :
  • après 72h de séchage à température ambiante   : 4000 N

If paper waste of the same composition is now compacted with the same amount of binder and water but without the addition of potassium siliconate, test tubes with the following resistances are obtained, determined using the PERRIER compression tester:

• in flexion:
  • green: 500 N
  • after 48 hours of drying at room temperature: 1000 N
  • after 2 hours of drying at 100 ° C: 1200 N
• in compression on fields:
  • after 72 hours of drying at room temperature: 4000 N

These test pieces being placed in a humid atmosphere, at 100% relative humidity and at 25 ° C, there is a swelling of platelets after 24h. After 72 hours, the material no longer has any cohesion.

This example shows that the addition of 10% of AGGLOFROID ^R 009 and 3% of potassium siliconate by dry weight relative to the weight of paper waste makes it possible to obtain compact materials satisfying the requirements of the technique, namely having sufficient mechanical resistance and resistance to humidity while remaining plumpable in a stationery pulper.

EXAMPLE 2

In a mixer of the Robot coupe type, on the one hand, 1000 g of crushed corrugated cardboard having a particle size of less than 0.5 cm are introduced and, on the other hand, 150 g of waste water from potato starch protein production, consisting of vegetable water, or red water, partially deproteinized, with 55% dry matter, sold under the name FONDLYS ^R 55007 by the company ROQUETTE FRERES. The mixture obtained is kneaded for 3 minutes, then 50 g of hydrated lime is introduced into it and the kneading is continued for 2 minutes. The mixture is then agglomerated by molding in the form of pallets with a side of 5 cm and a thickness of 1 cm under a pressure of 3432 10 ⁴ pascals.

The test pieces thus obtained have a cohesion to green sufficient to undergo transport.

• en flexion :
  • à vert   : 800 N
  • après 72h de séchage à température ambiante   : 1500 N
  • après 2h de séchage à 80°C   : 1500 N
• en compression sur champs :
  • après 72h de séchage à température ambiante   : 1500 N

The resistance of these test pieces, determined using a PERRIER compression tester, has the following values:

• in flexion:
  • green: 800 N
  • after 72 hours of drying at room temperature: 1500 N
  • after 2 hours of drying at 80 ° C: 1500 N
• in compression on fields:
  • after 72 hours of drying at room temperature: 1500 N

After drying for 72 hours at room temperature, the test pieces are immersed in a siliconate solution 10% potassium.

The test pieces absorb 5% of said solution. After drying at room temperature, they have a "beading" effect, that is to say a repellent effect vis-à-vis water, very marked.

These test pieces are then placed in an atmosphere humid, at 100% relative humidity and at 25 ° C. Any disintegration is not observed, even after several weeks. The mechanical strengths of these test pieces remain unchanged after this stay in a humid atmosphere. Likewise, the "sparkling" effect is preserved.

On the other hand, if an entire test tube is placed in cold water with stirring, it begins to disintegrate after 4 to 5h. If this plate is broken in several pieces before being placed in water, we get, after only two hours, a coarse pulp, sufficiently dispersed to be subjected to the work of a stationery disintegrator.

This example shows that the addition of 15% of FONDLYS ^R 55007 and 5% of hydrated lime by dry weight relative to the weight of waste paper waste, as well as the immersion in a potassium siliconate solution, make it possible to obtain compact materials with satisfactory mechanical strength and sufficient water resistance so that the compact material can be stored in a humid place. On the other hand, the compact material in question has a property of total repulpability.

EXAMPLE 3

In a mixer of the Robot coupe type, 500 g of paper waste having a particle size less than 2 mm and 500 g of paper waste having a particle size between 1 cm and 2 cm are introduced on the one hand, and on the other hand share, 200 g of a modified corn starch glue sold by the company ROQUETTE FRERES under the name AMILYS ^R 100, the dry matter of this glue being 35% by weight. The mixture is kneaded for 5 minutes and then 20 g of water-repellent product sold under the name HYDROFUGE 68 by RHONE POULENC are added. After two minutes of kneading, the mixture is agglomerated by molding in the form of rectangles 30 cm long, 12 cm wide, and 2 cm thick, under a pressure of 3432 10 ⁴ pascals. The samples thus obtained have a very high green cohesion, allowing all useful manipulations.

• en flexion :
  • à vert   : 2000 N
  • après 72h à température ambiante   : 4000 N
  • après 2h de séchage à 120°C   : 5000 N
• en compression sur champs :
  • après 72h à température ambiante   : 80000 N
  • après séchage 2h à 120°C   : 100000 N

The resistance of these test pieces, determined using a PERRIER compression tester, has the following values:

• in flexion:
  • green: 2000 N
  • after 72 hours at room temperature: 4000 N
  • after 2 hours of drying at 120 ° C: 5000 N
• in compression on fields:
  • after 72 hours at room temperature: 80,000 N
  • after drying for 2 hours at 120 ° C: 100,000 N

These test pieces are then placed in an atmosphere humid, at 100% relative humidity and at 25 ° C. Any disintegration is not observed, even after several weeks. The mechanical resistance of the test pieces remains unchanged after this stay in a humid atmosphere. The interior of test pieces show no trace at observation humidity.

On the other hand, if a test tube is placed in a beaker of cold water with gentle stirring for 4 to 5 hours, observe that the test tube begins to swell slightly and then that it disintegrates. After 6 to 7 hours, a paste is obtained. coarse paper, sufficient to be worked in a stationery refiner.

• en flexion :
  • à vert   : 500 N
  • après 72h à température ambiante   : 800 N
  • après 2h de séchage à 120°C   : 1000 N
• en compression sur champs :
  • après 72h à température ambiante : 2000 N
  • après 2h à 120°C : 5000 N

If paper waste of the same nature and of the same composition is compacted under the same conditions but in the absence of any binder, samples are obtained having the following resistances, determined using a PERRIER compression tester:

• in flexion:
  • green: 500 N
  • after 72 hours at room temperature: 800 N
  • after 2 hours of drying at 120 ° C: 1000 N
• in compression on fields:
  • after 72h at room temperature: 2000 N
  • after 2h at 120 ° C: 5000 N

These test pieces are then placed in an atmosphere humid at 100% relative humidity and at 25 ° C. There is a swelling of these test tubes after only 24 hours. After 96h, the compact material thus obtained no longer has no cohesion.

This example shows that the addition of 7% of AMILYS ^R 100 (in the form of an adhesive obtained by steaming) and 2% of WATER-REPELLENT 68 by weight relative to the weight of paper waste makes it possible to '' obtain agglomerates satisfying in all respects the requirements of the technique.

EXAMPLE 4

In a mixer of the Robot coupe type, 1000 g of crushed old paper with a particle size of less than 5 mm is introduced on the one hand and 100 g of AGGLOFROID ^R 313E and 250 g of drinking water containing 30 g of liquid on the other hand a fluorinated acrylic copolymer, marketed by the company ELF ATOCHEM under the brand FORAPERLE 321. The mixture obtained is kneaded for 5 minutes, then it is agglomerated by molding in the form of square panels 6 cm wide and 1 cm thick, under a pressure of 3432 10 ⁴ pascals. The samples thus obtained have sufficient green cohesion to undergo transport.

• en flexion :
  • à vert   : 500 N
  • après 48h à température ambiante   : 900 N
  • après 2h de séchage à 100°C   : 1300 N
• en compression sur champs :
  • après 72h à température ambiante   : 3500 N

The resistance of these test pieces is determined using a PERRIER compression tester and has the following values:

• in flexion:
  • green: 500 N
  • after 48 hours at room temperature: 900 N
  • after 2 hours of drying at 100 ° C: 1300 N
• in compression on fields:
  • after 72h at room temperature: 3500 N

These test pieces are placed in a humid atmosphere at 100% relative humidity and at 25 ° C. There is a swelling of these test tubes after 96 hours. After 144 hours, these test pieces have only a weak cohesion.

EXAMPLE 5 :

Test tubes, prepared under the same conditions that in example 4 above, are immersed in a FORAPERLE 321 solution at 50%. We see that the test tubes absorb 10% of the solution. After drying at room temperature, they have a slight effect "beading". However, after drying for 2 hours at 120 ° C, we notes that the "beading" effect obtained is very marked.

EXAMPLE 6

Test pieces, prepared under the same conditions as in Example 4 above, are immersed in a solution of pregelatinized potato starch with 5% dry matter, mixed with 20% calcium carbonate and 10% of FORAPERLE ^R 321. The test pieces thus absorb 5% of the solution. After drying at room temperature, these test pieces show practically no "beading" effect. On the other hand, after drying at 120 ° C for 2 hours, the "beading" effect is very marked.

Claims (10)

1. A compact water-resistant material made with crushed cellulose materials and characterised in that it is repulpable and in that it comprises:

   an effective quantity of an organic binder chosen from the group comprising the starches and the starch derivatives, flours, proteins, the by-products of starch production and extraction, the celluloses and their derivatives, the hemicelluloses and their derivatives as well as the mixtures of these products, and

   an effective quantity of a water-resistant agent chosen from the organosilicic waterproofing agents and fluorinated acrylic copolymers.
2. A compact material according to Claim 1, characterised in that the water-resistant agent is chosen from among the organosilicic waterproofing agents having a structural unit which satisfies the formula:

   

   in which R and R₁ which may be identical to or different from each other, are hydrogen or organic radicals chosen from the group comprising the methyl, alcoyl, fluoroalcoyl, possibly substituted phenyl, vinyl or their chlorinated, alcoxy, alcoylamino derivatives, the said compound being advantageously chosen from the group comprising non-reactive silicone oils, the silicone resins, the reactive silicone oils, in particular those which are hydroxylated, alcoylated, arylated, hydroalcoylated, hydroarylated, as well as mixtures of these products and the emulsions which may be prepared on a basis of these products.
3. A compact material according to Claim 1, characterised in that the organosilicic waterproofing agent is chosen from the group of siliconates to the general formula:

   

   in which

   R₂ is an alcoyl (C₁-C₁₀), alkenyl, (C₁-C₁₀) or aryl (C₆-C₁₀) group

   X is an atom of alkaline or alkaline earth metal and

   1 ≤ n ≤ 10,

   potassium siliconate being particularly preferred.
4. A compact material according to Claim 1, characterised in that the water-resistant agent is chosen from the possibly salified or quaternised fluoronated copolymers comprising by weight:

   a) 35 to 98% and preferably 69 to 93% of one or a plurality of polyfluoronated monomers to the general formula:

   

   in which Rf represents a straight chain or ramified perfluoro-alkyl radical containing 2 to 20 carbon atoms and preferably 4 to 16 carbon atoms, Q represents an atom of oxygen or sulphur, B represents a bivalent sequence linked to Q by a carbon atom and possibly comprising one or more atoms of oxygen, sulphur and/or nitrogen, one of the symbols R represents a hydrogen atom while the other represents a hydrogen atom or an alkyl radical containing 1 to 4 carbon atoms;

   b) 1 to 15% and preferably 5 to 11% and above all 7 to 10% of one or more monomers to the general formula:

   

   in which B' represents a linear or branched alkylene radical containing 1 to 4 carbon atoms, R' represents a hydrogen atom or an alkyl radical containing 1 to 4 carbon atoms, R₁ represents an alkyl radical containing 1 to 18 carbon atoms, hydroxy ethyl or benzyl, R₂ represents a hydrogen atom or an alkyl radical containing 1 to 18 carbon atoms, hydroxyethyl or benzyl or R₁ and R₂ together with the nitrogen atom form a morpholin, piperidin or pyrrolidinyl-1 radical;

   c) 1 to 50% and preferably 2 to 20% of one or more monomers to the general formula:

   

   in which R₃, R'₃, R₄ and R₅ are identical or different, each representing a hydrogen atom or an alkyl radical containing 1 to 4 carbon atoms and possibly

   d) up to 10% and preferably less than 5% of any monomer other than the monomers to formulae (I), (II) and (III).
5. A compact material according to any one of Claims 1 to 4, characterised in that the organic binder is chosen from among the starches, starch derivatives and/or the by-products of starch production or extraction.
6. A compact material according to any one of Claims 1 to 5, characterised in that it comprises:

   a proportion of 0.5 to 40% and preferably 1 to 25% and even more preferably 2 to 20% by weight of organic binder

   a proportion of 0.005 to 10%, preferably 0.025 to 6% and even more preferably 0.05 to 4% by weight of water-resistant agent, the percentages being expressed by weight in relation to the weight of crushed cellulose materials.
7. A compact material according to any one of Claims 1 to 6, characterised in that it comprises a proportion of 0.5 to 25% and preferably 1 to 5% of a hardening agent, the percentages being expressed by weight in relation to the weight of crushed cellulose materials.
8. A method of preparing a compact material according to one of Claims 1 to 7, characterised in that

   a) a crushed cellulose material, an organic binder from the previously defined group, an organosilicic waterproofing agent or a fluorinated copolymer and possibly a hardening agent are chosen;

   b) the waterproofing agent is mixed with a premixture containing the cellulose material and the organic binder, possibly in the presence of the hardening agent

   or the cellulose material, the organic binder and possibly the hardening agent are mixed;

   or the organic binder is mixed with at least one part of the waterproofing agent, the resulting composition being mixed with the cellulose material;

   c) the mixture thus obtained is subjected to a shaping treatment, for example by pressure, compression, agglomeration, compacting or extrusion;

   d) the remaining quantity or all of the waterproofing agent is applied to the surface of the compact product obtained at the end of stage c) above.
9. A method of producing a compact material according to any one of Claims 1 to 7, characterised in that

   a finely crushed cellulosic material, an organic binder from the previously defined group and possibly a hardening agent are selected,

   the cellulosic material, the organic binder and possibly the hardening agent are mixed,

   the resulting mixture is subjected to a shaping, for example by pressure, compression, agglomeration, compacting or extrusion,

   a chosen quantity of waterproofing agent is applied to the resulting compact material, for example by coating, impregnation, immersion, spraying or brushing.
10. A method according to one of Claims 8 or 9, characterised in that the material obtained at the end of the shaping treatment is subjected to an oven treatment in temperature conditions comprised between about 80-100°C and about 200-220°C.