JPS5952062B2 - roll of web material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a roll of web material, such as paper, plastic film, fabric or the like, wound around a core.

The well-known core (around which the web material is wrapped) is a preformed cylinder, generally made of glued cardboard or glued paper.

However, other types of wicks are also available. For example, two cardboard rings or two wooden plugs in the shape of a truncated cone with a central hole are used in many rolls.
These rings or plugs are placed at each end of the roll to ensure that the roll is wound correctly and has the correct shape, similar to the case with glued cardboard and paper cylinders. However, they still act as a type of hub on the roll as the web material is unwound from the periphery of the roll. However, in rolls of the type where the web material is unwound from the center of the roll, i.e. from the center hole of the roll, the core, usually in the form of a cardboard ring, is first removed so that the free end of the web at the center hole of the roll is removed. The web material can then be unwound from the inner periphery of the roll. Rolls of web material that are completely coreless, with the web material being unwound from the center of the roll, are of course well known, but rolls of this type have been found to be very susceptible to crushing, and therefore this Rolls are increasingly used, especially if the free end of the web material in the center of the roll is compacted, since it closes the central hole of the roll to such an extent that its free end cannot be pulled out. This is becoming less common. Roll cores that are solid are also known. These have a wide variety of shapes. Some take the form of wooden dowels, while others take the form of elongated discs of varying thickness. What solid cores have in common is that they cannot be used in rolls where the web material is unwound from the center of the roll. These cores are very difficult to remove from the roll as a result of the high friction against the web material. This friction makes it virtually impossible to pull the core axially out of the roll. These two advantages do not outweigh the disadvantages of these cores, even though the use of well-known preformed cores consistently produces stable rolls that do not collapse. Preformed cores, whether hollow or solid, have the shape of a tubular cylinder or ring, or are in the form of a dowel, disc or plug, and are relatively expensive. Additionally, they generally require constant storage space and require manual handling during use. This makes their use even more expensive. In addition, as mentioned above, they are not suitable for use in rolls of the type that unwind the web material from a central hole in the roll. The object of the present invention is to eliminate the drawbacks of the known preformed roll cores and to produce a new type of roll that does not require expensive storage space and manual handling.

According to an aspect of the invention, there is provided a cylindrical roll of web material having a central opening and forming a supply of said web material and having a cylindrical core within said central opening. the core has sufficient stiffness to support the roll against axial and radial crushing, characterized in that the core is stiff enough to support the roll against axial and radial crushing; a fixing agent is applied to at least one surface of the web material to solidify the core roll into a substantially rigid core, and the web material forming the core is integral with the web material forming the roll. the fixing agent has an adhesive strength lower than that of the web material, such that the roll of material on the core is in the same manner as the material of the cylindrical roll. In order to use it in the industry, it is rewound so that no core remains.

In this type of roll, there is no need to use a preformed core. Since the core is formed in series with the material of the roll during the initial winding operation of the roll itself, all the handling and space required for the known preformed cores is eliminated. The turns of material on the core are unwound from both the inside and outside of the core, along with the material wound around the core.

Therefore, the roll of the present invention is not limited to one type of unwinding, ie, from the outside or from the inside, as is the case with known rolls. In contrast, the roll of the present invention is designed to be unrolled equally from the outer periphery and from the inner periphery. The fact that the material in the core can be used in the same manner as the rest of the material in the roll makes it generally not economically viable to reuse this core compared to using known cores. This represents a direct savings, as it can be thrown away after use.

In a particularly preferred embodiment for the roll according to the invention, the core is tubular.

To facilitate unwinding of the web material from the center, this type of core can be provided with a free end of the web material on its inside. This free end is provided to facilitate gripping in order to facilitate unwinding from the inner periphery of the roll. The present invention will be explained in more detail below using preferred specific examples.

Rolls of web material made of crepe paper are made with a so-called central opening.

The paper is wound around a core inside the roll. According to the invention, the core is made in series with the web material wound thereon and is comprised of multiple turns of this web material. Each turn of this winding body is fixed to each other. For this purpose,
The first end of the crepe paper web is conventionally placed around a well-known, preferably expandable, rolling spindle.
During the formation of the roll, the rolling spindle is coated with water or a binder such as starch, CMC, etc. to form the roll core. PVA or 0 depending on the desired adhesive effect
．． The first plurality of windings are fixed to each other with a mixture of other water-soluble binders at a concentration of 0.05 to 2%,
Make it possible to rotate.

If the binder or fixative is water only,
The amount should be kept low so that the paper web is not wetted out. Preferably, the binder or fixative should be applied to the side of the web that is not in direct contact with the rolling spindle.

And if the fixative is an adhesive mixed with water, its viscosity should be kept low to ensure uniformity and good distribution. Should. Application of the fixative can be carried out in various ways.

For example, it can be applied by spraying or coating onto the web, or by press, groupless or other mechanical equipment to produce proper distribution on or in the web. By such application of fixative, the amount of fixative is adjusted so that the paper in the core of the roll is not adversely affected in practical use, and the entire roll including the core can be used.
If it is desired that the core be a virtually rigid and rigid tubular sleeve, the amount of fixative may be increased, or a water-free fixative or a hot melt of wax or glue may be used to achieve a similar effect. used.

Of course, a similar effect could be achieved by using the original fixative and instead increasing the number of turns on the core. By choosing a stronger adhesive, such as glue, and increasing the number of paper wraps, a harder and stronger core or cylinder can be obtained.

In practical tests using starch as a fixing agent on crepe paper, good results were obtained without the innermost layers of paper forming the core of the roll sticking together directly.

It is also possible to heat or cool the core during the manufacturing process.

In the production of rolls of other web materials, the fixative is
They are individually selected to secure the core in order to produce adequate strength in combination with the web material in question to form a functional core in the roll.

The present invention is not limited to the specific examples described above.

Claims (1)

[Scope of Claims] 1. A cylindrical roll of web material having no or little inherent stiffness, such as paper, plastic foil, fabric or the like, having a central opening. A cylindrical roll of web material having a cylindrical core within said central opening forming a supply of web material and having sufficient strength to support the roll against axial and reflective crushing; comprising a plurality of turns of said web material and a fixing agent applied onto at least one side of the web material forming the core to solidify the core turns into a substantially rigid core; The web material forming the roll is integrally continuous with the web material forming the roll, and the fixing agent has an adhesive strength lower than that of the web material such that the winding of the web material on the core A cylindrical roll of web material, characterized in that the body is unwound for use in the same manner as the material of the cylindrical roll, so that no residual core remains. 2. A cylindrical roll of web material according to claim 1, wherein the web is paper and the fixative is a mixture of water and a water-soluble binder. 3. A tubular roll of web material according to claim 2, wherein the binder is selected from the group consisting of starch, CMC and PVA. 4. A tubular roll of web material according to claim 2 or 3, wherein the binder is in a concentration between 0.5% and 2%. 5. Claims 1, 2 or 3, wherein the fixative is applied to the outer surface of the web material to avoid direct contact with the spindle on which the core is formed. A cylindrical roll of the web material described in paragraphs. 6. A cylindrical roll of web material according to claim 1, wherein the fixative is a water-free fixative. 7. A cylindrical roll of web material according to claim 1, wherein the turns on the core are unwound from the inner periphery of the core together with the material wound around the core. 8. A cylindrical roll of web material according to claim 7, wherein the core is cylindrical and has a free end on the inside, the free end being of the same material as the roll.