EP2167412B1 - Core intended to act as a support for a reel of paper - Google Patents

Abstract

A core intended to be used as a support for a roll of paper, especially toilet paper, is formed by winding at least one strip made of tissue, the strip being impregnated, at least locally, with starch so as to improve its stiffness. Thus configured, a core is provided having both a mechanical strength suitable for the envisaged use and a greatly improved ability to disintegrate relative to a cardboard core so as to allow it to be able to be disposed of directly in a toilet bowl without risk of blocking the soil pipe.

Description

The invention relates to a mandrel for supporting a reel of paper, especially toilet paper.

In the field of papers intended for domestic use, especially toilet papers or paper towels, it is known to present them in the form of rolls or coils. Said rollers are formed by winding the paper around a mandrel generally made of cardboard.

The choice of the board results from the compromise sought by the manufacturers between the adaptation of the material to the mechanical constraints of manufacture and the desire to limit the cost of the product in the end. It turns out that these mandrels are subjected during the manufacture of the rollers to various mechanical stresses whether during the passage in the winder, when packing the rolls in the packages or when stacking the roll packets on the pallets intended for their transport. The constituent material of these mandrels must in particular have good rigidity characteristics to withstand the loads and forces to which the rollers are subjected throughout their production and distribution cycle. A material that does not have sufficient strength would indeed cause a deformation of the individual rolls or a collapse of the stacks of rollers on the pallets. This would therefore have particularly harmful consequences on the quality of the products obtained or on the overall production yield of these rollers.

Until now, cardboard has been a very suitable solution for this purpose. It also had the advantage of being relatively cheap.

However, this type of cardboard core is now unsuited to the new needs of consumers to have a readily disposable material, in particular can be thrown into the toilet bowls.

Indeed, the consumer has long been in the habit of throwing the toilet paper coupons, after use, in the toilet bowl and flush the flush to eliminate them in the exhaust duct. This usually results in no obstruction of the duct since the Tissue paper material constituting these coupons disintegrates easily and quickly in the presence of water.

The same operation is no longer applicable when it comes to removing the cardboard core, once used all the paper reserve. Indeed, cardboard, being a material much less absorbent than tissue paper, disintegrates very slowly and with great difficulty in the water. This results in a virtually secure closure of the toilet exhaust duct, if the flush is actuated just after throwing said mandrel into the bowl.

The only alternative is to favor elimination of the mandrel in an external bin. However, this solution has the major disadvantage of unnecessarily increasing the amount of waste produced by all consumers. In the absence of being separated from other domestic waste, these cardboard cores are often not recycled or recyclable. This results in a significant increase in the volume of waste to be destroyed or stored in landfills, which goes against the current ecological concerns of our modern societies.

The document WO 2007/030749 discloses a mandrel consisting in particular of a water-soluble material.

The present invention therefore aims to solve the problems raised by this prior art and, in particular, to propose a mandrel that can easily disintegrate in the toilet.

For this purpose and in accordance with the invention, there is provided a mandrel for supporting a reel of paper, especially toilet paper, characterized in that it is formed by the winding of at least one strip in cellulose wadding, said band being impregnated at least locally with starch so as to improve its rigidity.

According to a particular embodiment of the invention, the impregnation rate of the cellulose wadding strip is between 0.05 and 0.50 g of starch per gram of cellulose wadding.

According to a preferred embodiment of the invention, the impregnation rate of the cellulose wadding is between 0.25 and 0.45 g of starch per gram of cellulose wadding.

According to another particular embodiment of the invention, the mandrel has a lower flat compressive strength of 5% or less than that of a similar cardboard mandrel.

According to a preferred embodiment of the invention, the cellulose wadding strip comprises several layers of cellulose wadding separated from each other by adhesive layers.

According to another preferred embodiment of the invention, at least some of said adhesive layers contain a mixture of glue and starch.

According to a particular embodiment of the invention, the cellulose wadding strip comprises between 2 and 24 layers of cellulose wadding, and preferably between 4 and 16 layers of cellulose wadding.

1. a) fourniture d'une première bande en ouate de cellulose comportant un ou plusieurs plis,
2. b) fourniture d'une seconde bande en ouate de cellulose comportant un ou plusieurs plis,
3. c) dépôt d'une couche adhésive sur au moins une surface externe de la première bande, ladite couche adhésive améliorant la rigidité du complexe formé par l'assemblage de la première et de la seconde bandes une fois séchée,
4. d) assemblage et pressage simultanée de la première bande avec la seconde bande de manière à ce que la surface externe de la première bande recouverte d'une couche adhésive vienne en contact avec une surface externe de la seconde bande, l'assemblage obtenu constituant au final une troisième bande,
5. e) séchage de la troisième bande,
6. f) utilisation de la troisième bande en remplacement de la première et/ou de la seconde bande dans les étapes a) à d),
7. g) répétition des étapes a) à e) jusqu'à l'obtention d'une troisième bande possédant le nombre de plis désirés,
8. h) enduction éventuelle des faces externes de la troisième bande avec au moins une couche à base d'amidon,
9. i) enroulement hélicoïdal de la troisième bande sur elle-même ou avec une quatrième bande identique à la troisième bande sous forme d'un tube creux
10. j) découpe d'un tronçon dudit tube pour former le mandrin.

The invention also relates to a method for manufacturing a mandrel as defined above, comprising the following steps:

1. a) providing a first cellulose wadding band having one or more plies,
2. b) providing a second cellulose wadding web having one or more plies,
3. c) depositing an adhesive layer on at least one outer surface of the first strip, said adhesive layer improving the rigidity of the complex formed by assembling the first and second strips after drying,
4. d) assembling and simultaneously pressing the first web with the second web so that the outer surface of the first tape coated with an adhesive layer comes into contact with an outer surface of the second web, the resulting assembly constituting final a third band,
5. e) drying the third band,
6. f) using the third band to replace the first and / or second band in steps a) to d),
7. g) repeating steps a) to e) until a third strip having the desired number of plies is obtained,
8. h) optionally coating the external faces of the third strip with at least one starch-based layer,
9. i) helicoidal winding of the third band on itself or with a fourth band identical to the third band in the form of a hollow tube
10. j) cutting a section of said tube to form the mandrel.

Thus configured, the invention is capable of providing a mandrel having both a mechanical strength adapted to the intended use and a greatly improved deliability with respect to a cardboard mandrel so as to allow it to be directly disposable in a bowl. toilet without risk of clogging the exhaust duct.

• la figure 1 représente une vue schématique en coupe transversale d'une bande en ouate de cellulose constituant un mandrin selon l'invention, et
• la figure 2 représente de manière schématique une installation destinée à former la bande de ouate de cellulose de la figure 1.

Other advantages and features will become more apparent from the following description of an exemplary embodiment according to the invention, with reference to the drawings in which:

• the figure 1 represents a schematic cross-sectional view of a cellulose wadding strip constituting a mandrel according to the invention, and
• the figure 2 schematically represents an installation intended to form the cellulose wadding strip of the figure 1 .

Starch comprises natural products of vegetable origin such as starches of wheat, corn, potato, rice, tapioca, sorghum, and the like, constituted by polymers or polyholosides of high molecular weight. Starch also means products derived from natural starch, converted by physical treatment, for example heating, physico-chemical treatment or biological treatment for example enzymatic, and starches derived or modified such as cationic, anionic, amphoteric starches, nonionic or crosslinked.

The cellulose wadding web comprises several layers of cellulose wadding, each layer having a basis weight of from about 15 to about 80 g / m ² and preferably from about 20 to about 40 g / m ² .

With reference to the figure 1 , it is schematically represented the structure of a cellulose wadding strip intended to form the mandrel of the invention.

This structure consists of the stack of 12 Cn layers of cellulose wadding associated with each other by means of 11 C'n adhesive layers.

Each of the Cn layers of cellulose wadding has a basis weight of 20 g / m ² .

Each of the adhesive layers C'n is formed either of a mixture of glue based on polyvinyl alcohol and polyethylene glycol type SWIFT® L998 / 4 marketed by Forbo and potato starch type AMYLOGUM CLS® marketed by the company AVEBE, only potato starch type AMYLOGUM CLOS®.

The weight of glue and starch in each of the C'n layers is given in Table 1 below. TABLE 1: Layer Glue weight (in g / m ² ) Starch weight (in g / m ² ) C'1 0 1.5 C '2 0.04 1.66 C '3 0 1.5 C'4 0.05 2.04 C'5 0 1.56 C'6 0.04 1.66 C'7 0 1.5 C'8 0.05 2.01 C'9 0 1.5 C'10 0.04 1.66 C'11 0 1.5

Subsequently, each of the outer faces of this strip was coated twice with a starch solution of the same type as that used in the adhesive layers C'n.

Thus, on the C1 and C12 layers, respectively 3.9 g / m ² and 3.45 g / m ² of starch were deposited.

It was determined that the web was ultimately impregnated at a rate of 0.11 g of starch per gram of cellulose wadding.

Said strip was then wound with another exactly similar strip to form a mandrel. The mandrel obtained has been subjected to a series tests to evaluate its mechanical strength and its ability to break down.

Similar tests were carried out on a commercial cardboard mandrel having the same thickness and length as the mandrel of the invention and being formed of a single strip having a basis weight of about 280 g / m ² .

Compression test:

The compressive strength was measured at both flat and edge of the mandrel, using the following method.

The mandrel to be tested is first cut in a cylindrical portion delimited by two opposite faces, perpendicular to the axis of the cylinder, said portion having a length of 50 mm in a direction parallel to the axis.

This cylindrical portion is then positioned between the two metal plates of a dynamometer, said plates being parallel to one another and spaced apart at a distance slightly greater than the length of the cylindrical portion, in the case of measuring the compression on singing, or its diameter, in the case of measuring the flat compression.

In the compression measurement on edge, the cylindrical portion is arranged to orient the axis of the cylinder in a direction perpendicular to the plane formed by one or other of the trays.

In the flat compression measurement, the cylindrical portion is arranged to orient the axis of the cylinder in a direction parallel to the plane formed by one or other of the trays.

These cylindrical portions are then compressed between the two plates, the compression speed being 10 mm / min.

Concurrently, the resistance opposite the mandrel is measured up to its maximum Rmax, that is to say just before the mandrel is irreversibly destructuring.

Five measurements were taken each time and the average of these was calculated.

The results are summarized in Table 2 below. TABLE 2 Chuck of the invention Cardboard like chuck Relationship between the two values Flat compression Rmax = 4.89 N Rmax = 5.15 N 0.95 Singing compression Rmax = 153 N Rmax = 278 N 0.55

It is therefore found that the mandrel according to the invention has a flat compression resistance substantially equal to that of a similar cardboard mandrel.

Since the main constraints on the mandrel during its production and distribution cycle are essentially flat, we can consider that the mandrel of the invention fully meets the needs at this level.

Disintegration test:

The mandrel delicability was measured in accordance with NF Q34-020 with and without agitation.
The results are summarized in Table 3 below.
It is therefore found that the mandrel according to the invention is disintegrated at least 10 times faster than a similar cardboard core formed of a single strip of weight equal to 280 g / m ² , whether with stirring or without stirring.

It is also observed that the mandrel begins to disintegrate in water at least twenty times faster than a similar cardboard core obtained by winding a single strip of cardboard with a basis weight of 280 g / m ² .

By similar mandrel means a mandrel having substantially the same diameter and the same length as the mandrel of the invention. TABLE 3 Chuck of the invention Cardboard like chuck NF Q34-020 (with agitation) - the mandrel begins to disintegrate before 5 sec - the chuck begins to disintegrate at about 3 min the mandrel is completely disintegrated after about 60 seconds (fibrous suspension) - the mandrel is completely disintegrated after 10 min (pieces <= 1 cm ² ) NF Q34-020 (without agitation) - the mandrel is completely wet in 4 sec - the mandrel is completely wet in 160 sec - turns start to open after 30 sec - the turns start to open after 10 min

Evacuation test:

A mandrel is placed in a domestic evacuation system consisting of a toilet bowl connected to a pipe network with a total length of 18 m.

A certain amount of water is discharged by means of a conventional flushing device opening into the bowl so as to evacuate the mandrel out of the bowl and to cover the entire 18 m of pipes.

The amount of water required for this evacuation is measured for both a mandrel of the invention and for a similar cardboard mandrel formed of a single web of weight equal to 280 g / m ² .

In the case of the mandrel according to the invention, it takes about 6 I of water for the mandrel to be discharged from the bowl and travels the 18 m of pipes.

In the case of the similar cardboard mandrel, the mandrel does not travel all 18 m of pipelines even after spilling more than 50 I of water.

With reference to the figure 2 , it is shown schematically an installation for forming the cellulose wadding strip constituting the mandrel of the invention.

A first strip 10 of tissue paper having only a single fold is fed from a first coil 10A towards a sizing station. Said station comprises a screen roll 1 immersed in a gluing solution 2 based on glue and starch contained in a storage tank 3, said roll 1 subsequently transferring said gluing solution 2 onto an applicator roll 4.

During the passage of the first band 10, said applicator roll 4 is brought into contact with one of the outer surfaces of this band 10 so as to deposit an adhesive layer on said outer face.

Once glued, said first strip 10 is pressed with a second strip 20 of tissue paper fed from a second coil 20A, so that the adhesive layer is trapped between the two said strips 10 and 20. The pressing station is constituted a smooth steel roll and an elastomer roll 6 having a hardness of about 95 shore A, separated so as to create a nip 7 through which the assembly of the first and second webs 10 and 20.

This results in the formation of a third band 30 at the outlet of the pressing station, which comprises two outer folds of tissue paper and an adhesive inner layer.

Said third strip 30 is then heat-dried at 140 ° C., passing inside a calendering station 8 formed of two heated rolls and finally wound in the form of a third roll 30A.

Depending on the number of folds that the tissue paper web will eventually have, it may be necessary to use this third coil 30A in place of the first 10A and / or the second coil 20A and repeat again the previously mentioned steps. Thus, it will be possible to repeat as many times as necessary the operation below so as to obtain a tissue paper strip having exactly the desired number of plies.

Subsequently, and using an additional coating station (not shown), each of the outer faces of the resulting strip is coated with one or more starch-based layers, which will give it an improved rigidity.

The starched strip is the basic material used in forming the mandrel. This type of mandrel is generally formed by the helical winding of one or more strips around a shaft. The resulting hollow tube is then cut into sections of equal length, each of the sections forming a mandrel according to the invention.

In place of the method described above, it is also conceivable to operate a simultaneous winding of several strips of tissue paper by means of a winding device having as many feed stations as strips to wind, the number of bands corresponding to the number of layers of cellulose wadding that it is desired to integrate into the mandrel.

Depending on the mechanical strength, especially in compression, that one seeks to obtain for this mandrel, as well as its ability to disintegrate more or less easily and quickly, it is possible to vary the number of layers of tissue paper which will be formed each band and the total amount of starch impregnated each band.

In particular, it turns out that an ideal solution is to use between 2 and 24 layers of tissue paper, and preferably between 4 and 16 layers of tissue paper.

Furthermore, the strip will be impregnated with starch at a level of at least 0.1 g of starch per gram of cellulose wadding and preferably between 0.25 and 0.45 g per gram of cellulose wadding.

Claims (8)

1. Core intended to be used as a support for a roll of paper, especially toilet paper, characterized in that it is formed by winding at least one strip made of tissue paper, said strip being impregnated, at least locally, with starch so as to improve its stiffness.
2. Core according to the preceding claim, characterized in that the degree of impregnation of the tissue paper strip is between 0.05 and 0.50 g of starch per gram of tissue.
3. Core according to the preceding claim, characterized in that the degree of impregnation of the tissue paper strip is between 0.25 and 0.45 g of starch per gram of tissue.
4. Core according to any one of the preceding claims, characterized in that the strip comprises several layers of tissue paper (C1-C12) separated from each other by adhesive layers (C'1-C'11).
5. Core according to the preceding claim, characterized in that at least some of said adhesive layers (C'1-C'11) contain a mixture of adhesive and starch.
6. Core according to any one of the preceding claims, characterized in that the strip comprises between 2 and 24 layers of tissue paper.
7. Core according to the preceding claim, characterized in that the strip comprises between 4 and 16 layers of tissue paper.
8. Method of manufacturing a tissue core, comprising the following steps:

   a) supplying a first strip (10) made of tissue paper comprising one or more plies;

   b) supplying a second strip (20) made of tissue paper comprising one or more plies;

   c) depositing an adhesive layer on at least one outer surface of the first strip (10), said adhesive layer improving the stiffness of the complex formed by the assembly of the first (10) and the second strip (20) once dried;

   d) simultaneous assembly and pressing of the first strip (10) with the second strip (20) so that the outer surface of the first strip (10) covered with an adhesive layer comes into contact with an outer surface of the second strip (20), the assembly obtained forming, at the end, a third strip (30);

   e) drying the third strip (30);

   f) use of the third strip (30) in replacing the first (10) and/or the second strip (20) in steps a) to d);

   g) repetition of steps a) to e) until a third strip (30) having the desired number of plies is obtained;

   h) optional coating of the outer faces of the third strip (30) with at least one starch-based layer;

   i) spirally winding the third strip (30) around itself or with a fourth strip identical to the third strip (30) in the form of a hollow tube; and

   j) cutting a section of said tube to form the core.

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