GB2331042A

GB2331042A - Reels of adhesive wrapper blanks

Info

Publication number: GB2331042A
Application number: GB9824404A
Authority: GB
Inventors: Alberto Laghi; Alessandro Minarelli
Original assignee: GD SpA
Current assignee: GD SpA
Priority date: 1997-11-07
Filing date: 1998-11-09
Publication date: 1999-05-12
Anticipated expiration: 2018-11-09
Also published as: GB9824404D0; ITBO970662A0; GB2331042B; IT1296543B1; DE19851089A1; ITBO970662A1

Abstract

A method for making reels 10 of light sheet material, in particular for the production of soft wrappers, starting with a band 1 which has at least one longitudinal strip 2 of adhesive applied along one lateral edge of the band 1, envisages the application, along the lateral edge of the band 1 opposite that to which the longitudinal strip 2 was applied, of a corresponding longitudinal strip 4 of thickening material; where the strip of thickening material 4 is designed to balance the thickness of the band 1 for winding into a reel 10. The thickening material 4 may be the same adhesive as the longitudinal strip 2. The method achieves a reel of wrapper blanks having a cylindrical shape, preventing the reel from becoming bell-shaped.

Description

i 2331042 1 A method for making reels of light sheet material, in

particular for the production of soft wrappers, and a reel made according to this method The present invention relates to a method for making reels of light sheet material, in particular for the production of soft wrappers.

The use of soft wrappers, obtained from a band of paper, is known and widespread, for example, for making soft packets for cigarettes and other similar products.

Such wrappers are made by automatic machines which use reels of readyprinted paper. The band of paper unwound from the reels is cut to size and folded in such a way that it envelops the product to be packaged; the wrapper obtained in this way is sealed using special adhesives already applied to the band of paper.

in accordance with a known technique, localised doses of a suitable vinyl glue are applied to the band of paper as it is unwound from the reel. However, vinyl glues are relatively slow-drying and the packaging machines must be fitted with long conveyor means, which allow the band of paper to ,, 1---\ 2 is which the adhesive was applied sufficient transit time for the adhesive to reach the desired dryness. Thus,, machines which use this technique for application of the adhesive are very large.

In accordance with another known technique, the necessary localised doses of a so-called "hot melt" glue are applied to the band of paper before it is wound into a reel. During use, that is to say, when the reel is unwound, the adhesive is heated in order to bring it to a suitable adhesive state.

The adhesive is applied in segments along a longitudinal strip on the band of paper, located near one of the lateral edges of the band, and along a transversal strip on each portion of the band which will be used to form an, individual wrapper. The above-mentioned longitudinal strip of adhesive causes asymmetry in the thickness of the band of paper, which is obviously thicker along the lateral edge to which the adhesive was applied.

When the reel is made, the marginal thickness of the band of paper causes a gradual increase in the diametral size of the reel wound at the lateral edge to which the adhesive was applied. Therefore, in this case, the reel becomes bell-shaped, the phenomenon increasing with the diametral size of -1 - ---1 3 the reel.

The phenomenon which sees the reel of paper to which adhesive was applied become bell-shaped leads to significant disadvantages during use. Such reels tend to unwind during transport and lose their coils when handled. Moreover, as the reel is unwound, there are centring problems which may compromise the correct execution of processing.

The aim of the present invention is to provide a method which allows the simple, efficient production of reels of light sheet material, such as paper, to which adhesive has been applied, but which are cylindrical in shape.

In accordance with the present invention, a method is provided for making reels of light sheet material, in particular for the production of soft wrappers, starting with a band which has at least one longitudinal strip of adhesive along one lateral edge, characterised in that it envisages the application, along the lateral edge of the band opposite that to which said longitudinal strip was applied, of a corresponding longitudinal strip of a thickening material, designed to balance the thickness of the band when it is wound into a reel. The present invention also relates to a reel of _1 4 is light sheet material, in particular for the production of soft wrappers.

In accordance with the present invention, a reel of light sheet material is made, in particular for the production of soft wrappers, obtained starting with a band which has at least one longitudinal strip of adhesive along one lateral edge, characterised in that the lateral edge of the band opposite that to which said longitudinal strip was applied also has a longitudinal strip, consisting of a thickening material and designed to balance the thickness of the band.

The invention is described below with reference to the accompanying drawings, which illustrate an embodiment of the invention, without llmiting its scope of application, and in which:

Figure 1 is a plan view of a portion of a band of paper to be used to make a reel in accordance with the method disclosed; Figure 2 is a schematic cross-section of a reel made in accordance with the method disclosed, using the band of paper in Figure 1; Figure 3 is a schematic cross-section of a conventional reel.

With reference to the accompanying drawings, the numeral 1 indicates a band of sheet material, in particular paper, for the formation a reel 10 for the production of soft wrappers, not illustrated. in the known way, the band of paper 1 has a longitudinal strip 2 of adhesive on one side, applied in segments along one lateral edge of the band 1, and a transversal strip 3 of adhesive, on successive portions of the band 1, for the formation of an individual wrapper. The adhesive is preferably a glue of the "hot melt" type.

The band of paper 1 has a longitudinal strip 4 of a thickening material, applied in segments along the lateral edge opposite that to which the strip of adhesive 2 was applied. The longitudinal strip of thickening material 4 is designed to balance the thickness of the band 1 for its subsequent winding into a reel.

The strip of thickening material 4 may be produced using the same adhesive as was used for the longitudinal strip 2 and transversal strips 3. obviously, when the band of paper 1 is used, the thickening strip 4 is not subjected to the heating which activates the "hot melt" glue of the strips of adhesive 2, 3.

When the reel 10 is formed, the longitudinal strip 6 is 2 of the band of paper 1 causes a gradual increase in the diametral size of the reel wound, at the lateral edge to which the adhesive was applied. Therefore, if the thickening strip 4 were not present, the reel would become bell-shaped, as illustrated by way of example in Figure 3, in which the numeral 11 indicates the reel made starting with a band of paper 1.

The presence of the thickening strip 4 allows the thickness of the band of paper 1 to be balanced, equalling the marginal increase in thickness caused by the longitudinal strip 2 of adhesive.

Therefore, as it is wound, the reel 10 made using the band 1 thus prepared is perfectly cylindrical, as illustrated in Figure 2. The cylindrical shape of the reel 10 is maintained constant as the diametral size of the reel increases, as indicated by the dashed line 10a again in Figure 2.

The method described, therefore, achieves the aim of providing a reel of paper and similar materials, to which adhesive has been applied, having a perfectly cylindrical shape, preventing the reel from becoming bellshaped, as occurs in the case of conventional reels.

it should be emphasised that said result i 7 achieved in a simple, economical manner, in particular because the same adhesive as was applied to the band of paper 1 to seal the wrappers may be used as the thickening material.

8

Claims

Claims

A method for making reels of light sheet material, in particular for the production of soft wrappers, starting with a band having at least one longitudinal strip of adhesive along one lateral edge of the band, the method being characterised in that it envisages the application, along the lateral edge of the band opposite that to which the longitudinal strip was applied, of a corresponding longitudinal strip of thickening material, the latter being designed to balance the thickness of the band for winding into a reel.

2) 3) The method according to claim 1, characterised in that it envisages the creation of the longitudinal strip of thickening material using the same adhesive as was applied along the longitudinal strip on the band.

A reel of light sheet material, in particular for the production of soft wrappers, obtained starting with a band having at least one longitudinal strip of adhesive along one lateral 9 edge of the band, the reel being characterised in that it envisages the application, along the lateral edge of the band opposite that to which the longitudinal strip was applied, of a longitudinal strip of thickening material, the latter being designed to balance the thickness of the band.

4) 6) The reel according to claim 3, characterised in that the thickening material consists of the same adhesive as was applied along the longitudinal strip on the band.

The method for making reels of light sheet material, in particular for the production of soft wrappers, substantially as described with reference to any of the accompanying drawings.

The reel of light sheet material, in particular for the production of soft wrappers, substantially as described with reference to any of the accompanying drawings.