The invention relates to a roll provided with a lightproof packaging, which roll consists of, for example, a web of light-sensitive material, such as a web of photographic paper, which is wound around a core, which lightproof packaging consists of two discs, means for the lightproof sealing of the outer lateral circumferential edges of the roll and a starting strip or leader, which starting strip or leader is made of a lightproof material and which star¬ ting strip is fastened in line with the web at the free end of the web, which two discs are likewise made of a light¬ proof material, which discs each cover one of the circular side faces of the roll, and which sealing means for the lightproof sealing of the outer lateral circumferential edges of the roll are made of an elastic, opaque sheet of material and which sealing means are arranged in a stret¬ ched state, so that the transition at the two outer circum¬ ferential edges on either side of the roll, where one of the edges of the starting strip and one of the circular discs approach one another, is covered, specifically such that a part of the sealing means covers the outer surface of the roll and another part of the sealing means covers the side faces of the roll.

Rolls of light-sensitive material, such as for example photographic paper, need to be surrounded by a lightproof packaging in order to prevent the material being inadver¬ tently exposed to light prematurely during storage and/or transportation, resulting in it becoming unusable or not readily usable for the photographic industry in this man- ner.

European Patent Application EP-0,599,001 discloses a roll of light-sensitive material which is packaged in lightproof material, discs whose diameters essentially correspond to

the diameter of the roll to be packaged covering the side ^" faces of the roll. In this packaging, the transition be¬ tween the lightproof leader and the discs is covered with the aid of strips. These are first of all prestretched before they are applied to the leader. However, the pres¬ tretched strips are only applied to the leader after the leader has been wrapped around the roll. This has the disadvantage that an extra operation has to be carried out during packaging. Also, the strips have to continue over the end of the leader, since otherwise the packaging could be detached too easily. A drawback of this, however, is that the packaging cannot be broken easily, especially not if the strips are wrapped around the outer face of the roll a number of times. For this purpose, the strips have to be provided with weakened portions in order to be able to tear the strip. Another drawback of this known packaging is that the strips can only be made of a material which permits little elasticity. If the elasticity were to be too high, then the seal or the strips would seek to return to the initially unstretched state when broken, as a result of which the leader, with the strips stuck thereto, would curl up and would no longer be able to be pulled through the narrow outlet opening in the cartridge in which the roll of photographic paper is held and enclosed before the packa- ging can be removed from it. When the possible elasticity of the strips is only low, they can also only be folded a short distance over the edge of the roll, since otherwise they will not lie smoothly against the side face of the roll. With a possible elasticity of approximately 10%, the strip can only project 5 mm over the edge with a roll diameter of 10 cm, as a result of which it is not possible to ensure sufficient exclusion of light. With a roll diame¬ ter of 1 cm, the strip can barely project 0.5 mm over the edge.

The invention also relates to a method for the lightproof packaging of a roll of light-sensitive material, which roll of material consists of a web of a- specific width, which web is or has been rolled up around a core to form a roll.

the lightproof packaging consisting of two discs, a star- ^" ting strip or leader and sealing means for the lightproof sealing of the outer lateral circumferential edges of the roll, by which sealing means the two edges of the roll which correspond to the transition from the discs to the leader are sealed so as to be lightproof, in which case the starting strip or leader is made of a lightproof material and is or has been fastened at the end in line with the web, the two discs, which are likewise made of lightproof material, each also being placed against one of the side faces of the roll, whereupon the sealing means, which are made of an elastic, lightproof material, are partially fastened onto the starting strip such that parts of the sealing means project on either side of the roll, whereupon the leader is wrapped around the roll with the sealing means.

A method of this kind is known from another European Patent Application EP-A-0, 488, 738. The packaging described in this patent consists, inter alia, of discs which cover the side faces of the roll which is to be packaged. The diameter of these discs is greater than the diameter of the roll. A leader of essentially the same width as the roll is wrapped around the roll. Two strips made of an elastic material, of which part of the strips projects at the side of the lea¬ der, are fastened onto the side edges of the leader. These projecting edges will fold elastically around the projec¬ ting edges of the discs when the leader is wrapped around the roll together with the strips which have been stuck to it in the unstretched state.

A disadvantage is that the packaging can be damaged by the projecting edges of the discs after this known packaging has been applied around a roll of material in this manner. When the roll is or has been unrolled, the overlapping elastic strips on the edges of the discs are subjected to heavy loads and light may pass through. These disc-shaped projecting parts will also become damaged very rapidly during transportation, especially since the strips are

stretched at the most vulnerable locations. Because the projecting edges of the discs have to be surrounded by the strips, a relatively large amount of material is required for the strips. Also, a roll of this kind contains less photographic material than is possible with regard to the lateral discs, while the cartridge in which they are placed needs to have more space than is necessary. The cartridge has to be large enough for the large circular discs to be able to be placed therein.

The object of the invention is a roll provided with a lightproof packaging and a method for applying a lightproof packaging around a roll of light-sensitive material which do not exhibit the abovementioned disadvantages of the known packaging and methods.

This object is achieved using the invention in that the part of the surface of the sealing means which covers the leader is essentially covered by fixing means. This measure means that circumferential edges of a roll of photographic material of this kind can be covered by one or more strips of a very elastic material, because as a result of the fixing means the elastic sealing strips will not immediate- ^' ly spring back to the original unstretched state when the packaging is broken and shortly thereafter. As a result, after the packaging has been broken, the leader can be pulled out of the cartridge, in which case the leader will still remain in the original flat position.

In a preferred embodiment, the fixing means are made of a sheet of nonelastic material. This can easily be applied in the same operation, for example by means of gluing. Due to the fact that the material is nonelastic, the material will considerably delay the return of the prestretched elastic strips to their original shape.

In a preferred embodiment of the lightproof packaged roll according to the invention, the sealing means consist of a single strip of elastic material, the two lateral edges of

which on either side of the roll project outwards, and which strip is fastened onto the outwardly directed surface of the leader by means of adhesives, and in that the fixing means consist of a single band of nonelastic material, which is fastened onto the outwardly directed surface of the strip of elastic material by adhesives. This measure means that the sealing means cover the entire roll, as a result of which the roll is packaged not only by the leader or starting strip but also by the sealing means, so that an even better packaging is obtained. Due to the fact that the sealing means consist of a single sheet, this can be ap¬ plied around the roll quickly and easily in a single opera¬ tion.

In another preferred embodiment of the invention, the sealing means consist of two strips of elastic material, the two edges of the roll each being covered with one of the strips such that part of each strip projects outwards over the edge of the roll, which strip is fastened onto the outwardly directed surface of the leader by means of adhe¬ sives, the fixing means consisting of a band of nonelastic material, which is fastened onto the outwardly directed surface of the strip of elastic material by adhesives. This means that a sufficiently lightproof covering is obtained for the transition region between the discs at the side faces of the roll and the packaging of the casing of the roll using a minimum amount of material.

Preferably, the elastic strip of elastic material is made of an opaque material, which material can be stretched elastically by at least 10% or more, such as for example polyolefin. This high limit of elasticity means that a broad edge of the material curls firmly around the circum¬ ferential edge of the discs.

The elastic strip preferably ends before the end of the leader, so that a small piece of the leader still projects The bands preferably are made of a material which is non¬ elastic but easy to tear, such as paper. As a result, the

bands will not impede the removal of the packaging unneces ^" - sarily. The band of nonelastic material preferably continu¬ es past the end of the starting strip and the elastic strip, so that the band is applied over the entire circum- ference of the roll. In this case, the band preferably starts at or near the start of the elastic strip, as a result of which the band and the strip can be applied at the same time.

The starting strip is preferably made of a material which is difficult to stretch, such as for example medium-density polyethylene. As a result, the prestretched strip is enclo¬ sed between two layers which are nonelastic or of low elasticity, as a result of which the strip cannot easily return to its original shape.

In a further preferred embodiment, the lightproof means are provided with a weakened line or an easy-to-break border near the edge of the roll, so that the packaging can be removed easily and without any great effort. The strip tears at the predetermined location of the weakened line, so that undesirably large residues- are prevented from remaining on the lateral discs. This weakened line prefera¬ bly comprises perforations, since these can be applied easily. The weakened line is preferably applied such that it is situated at the side face of the roll. The residues which remain on the lateral discs are as a result smaller and, consequently, will not be in the way when the roll is unwound and rewound.

The object of a roll of photographic material packaged in such a manner is also achieved according to the invention using a method, in that the sealing means, before being fastened onto the starting strip or leader, are stretched and are fastened onto the starting strip in a stretched state, in which case the parts of the sealing strips which project laterally from the roll will be folded against the side face of the roll, after which fixing means are then arranged on the outwardly directed surface of the sealing

means more or less simultaneously with the application of ^" the sealing means.

According to this method, a roll of photographic material can be packaged entirely automatically in one operation, in which case all parts of the packaging can be applied ap¬ proximately simultaneously. This also means that the pro¬ jecting parts or edges of the strips fold a relatively large distance over the edge of the roll and thus over the discs when the starting strip is wound around the roll.

Very thick and very elastic material can be used for packa¬ ging rolls of photographic material according to the method of the invention, as a result of which a very lightproof exclusion of light is obtained, because the sealing strips can extend a distance of a few centimetres over the edge of the roll if the roll has a diameter of 100 mm. Even with a roll diameter of only 2 cm, it is still possible for the strip to project a few millimetres over the edge if the possible elasticity of the sealing strip is more than 30%.

In a preferred embodiment of this method, the fixing means consist of a band of a sheet of nonelastic material. Since the material is nonelastic, the return of the prestretched elastic strips to their original shape will be considerably delayed. The bands can be wound around the roll in a rapid and simple manner.

The elastic sealing strips are preferably fastened onto the starting strip or leader with the aid of adhesives which remain plastic, such as a plastic adhesive. This measure means that the prestretched strips can creep slowly back into their original form after the removal of the packaging without the starting strip becoming wrinkled in the pro¬ cess. The starting strip can consequently be reused for rewinding the roll, as a result of which the roll can be rewound if desired.

The sealing strips and fixing bands are preferably arranged on the roll at the same time as the starting strip is

rolled up around the roll. As a result, a simple method which can be carried out rapidly and can be easily automa¬ ted is obtained.

Preferably, the adhesives are applied to the strip. It is then impossible for any glue to be inadvertently placed on the roll where the strip is not fastened and glue is also prevented from getting onto the light-sensitive material.

The fixing bands are preferably provided with a layer of adhesive, as a result of which they can be applied easily.

The starting strip is preferably provided at the end with a narrowed portion, the strips ending before the narrowed portion of the leader. The starting strip consequently has a gripping point by which the user can quickly and easily pull away the starting strip from the roll. The bands preferably end past the narrowed portion of the leader, so that they completely cover the strips.

The side faces of the roll are preferably covered or have been covered by a single circular disc of lightproof mate¬ rial, before the leader is rolled up on the roll, a second cylindrical disc being arranged concentrically with respect to the first disc after the leader has been rolled up on the roll using sealing strips and fixing bands. As a re¬ sult, the folded-over edge of the strip is sufficiently and firmly enclosed between the two discs, so that the strip is fixed better and a good light seal is obtained.

The cylindrical second disc is preferably arranged such that the edge of the second disc projects over the edge of the strip, the second disc being fastened onto the side face of the roll with the aid of adhesives, so that the folded-over edge of the strip is correctly enclosed between the two discs.

The start of the elastic strip, after it has been stretched with the aid of auxiliary means, for example a small adhe-

sive strip, is preferably fastened onto the leader and is ^" then fastened over a portion of the outwardly directed surface of the leader using adhesives.

The prestretched strips are preferably fastened onto the starting strip with the aid of a very high bonding glue. Since the stretched strips seek to spring back to their original length, very high shear forces are exerted on the glued joint. Very high bonding glues are known, inter alia, from the aircraft industry and can withstand high forces and are consequently particularly suitable for fastening the stretched lightproof means onto the unstretched star¬ ting strip.

The starting strip does not have to be exactly as wide as the web of light-sensitive material. Since the lightproof means seal the edges of the roll against light over its entire circumference, the width of the starting strip can deviate within broad limits and may be up to 10 mm narrower than the web of light-sensitive material.

The invention will be explained in more detail with refe¬ rence to the drawings, in which:

Figure 1 shows a view of a roll of material with an elastic sheet fastened to one side thereof;

Figure 2 shows a view of a disc for covering the side face of the roll; Figure 3 shows a roll of material packaged according to the invention; Figure 4 shows a detail of the top of the roll where the disc and the elastic sheet overlap one another; Figure 5 shows a detail of the manner in which a supporting or closure cap is fastened in the hollow core;

Figure 6 A, B, C, D, E, F and G show the method for packaging a roll according to the invention; Figure 7 shows another possible embodiment of a packaging according to the invention consis-

ting of two sheets of an elastic film; Figure 8 shows a roll in accordance with Figure 7 with fixing means; Figure 9 shows a roll in accordance with Figure 7 and 8 after packaging;

Figure 10 shows a roll according to another possible embodiment of the invention; Figure 11 shows a roll in accordance with Figure 10, the packaging having been applied; Figure 12 shows a front view of a roll in accordance with Figures 10 and 11 with projecting side flanges .

Figure 1 shows a roll 1 consisting of a hollow core 2 around which a web 3 of photographic material has been wound. A starting strip or leader 4 is fastened at the end of the web 3. The starting strip 4 consists of a web of plastic of low elasticity, for example polyethylene, such as medium-density polyethylene, to which carbon has been added to make the material sufficiently lightproof. A sheet 6 of an elastic, opaque material whose width is greater than the width of the roll 1 is fastened at a location 5 over the entire width of the starting strip. The extra width of the sheet 6 with respect to the starting strip 4 is approximately 1 cm on either side. After the sheet has been stretched slightly, the sheet 6 is fastened to the starting strip 4, at the location indicated by the referen¬ ce numeral 5, across the entire width of the starting strip 4 and over a length of approximately 1 to 2 cm, using an easy peel layer.

Figure 2 shows a disc 7 such as can be placed against the side faces of the roll 1 in order to seal the side faces of the roll 1 in a lightproof manner. In this instance, the disc 7 consists of a plurality of layers. The first and third or outer layers consist of an annular disc 8 made of a rigid, opaque plastic, and the second layer or middle layer consists of a disc 9 which is made of an opaque plastic which is readily deformable. The three discs 8, 9

are sealed, stuck or connected in some other manner to one another along the entire circumference by the edges 10 in the vicinity of the circumference.

Figure 3 shows a roll of material 1 after it has been packaged according to the invention. The sheet 6 has been wound around the roll 1 after having been tensioned and after a disc 7 has been applied against the side faces of the roll 1 on either side. Due to the tensioning of the sheet 6, the sheet 6 lies taut around the roll, while the laterally projecting edges 11 of the sheet 6 press on the two discs which have been placed against the side faces of the roll. The sheet 6 consequently seals the transition region between the circumferential edges of the discs 7, on the one hand, and the lateral edges of the starting strip 4, on the other hand, in a lightproof manner.

Figure 4 shows a detail of the roll in cross-section. A disc or flange 7 consisting of two annular discs 8, between which a disc 9 of a material which is readily deformable is placed, is placed against the side face of the rolled-up web 3 of photographic material. The three discs 8, 9 and 8 are sealed together in the vicinity of the circumference and the elastic disc 9 is provided in the vicinity of the circumference with a perforated edge 12 which can be broken or stretched easily. The starting strip 4 is long enough to be wrapped around the roll of photographic material twice, so that the photographic material can be well protected from light. One end of the elastic sheet 6 is fastened to the starting strip 4 with the aid of an easily detachable glue or layer of adhesive 13, for example a so-called easy peel layer. The elastic sheet 6 is then tensioned and wrapped once around the roll 1 and, at the same location 5 where the start of the sheet 6 is fastened to the starting strip, is likewise fastened tensioned to the outer edge of the starting strip across the entire width of the roll with the aid of a layer of adhesive 14. The lateral edges 11 of the prestretched sheet 6 then press against the discs 7.

Figure 5 shows in more detail the way in which a supporting cap 15 is placed in the core, which cap presses the readily deformable layer 9 inwards, this layer being torn off at the perforated edge 12 (see Figure 4).

Figures 6 A, B, C, D, E, F and G show the method of apply¬ ing the elastic sheet 6 around the roll 1 consisting of a web of photographic material 3 with a starting sheet or leader 4 fastened in line with it. Figure 6A shows the roll 1 with the leader 4. Subsequently an easy peel layer (Figu¬ re 6B) is applied over the width of the leader 4 at the location 5. Then (Figure 6C), one end of the elastic sheet 6 is fastened to the leader on the easy peel layer 13 after the sheet has been stretched slightly. The leader 4 is then wrapped around the roll 1 (Figure 6D), followed by the elastic sheet 6 (Figure 6D). For this purpose, adhesives are initially applied on the outer edge of the leader of the roll at the location 5, as a result of which the elas¬ tic sheet 6 will adhere to the leader at that position. The excess 16 of the elastic sheet 6 is then removed. Figure 6G shows the roll after it is unrolled by means of the projec¬ ting portion 17 of the leader 4, for example after the roll has been placed in a lightproof cartridge 18.

Preferably, the starting strip or leader is made of materi¬ al which consists of from 4% to 6% of high-density polye¬ thylene, 4% to 6% of soot, 0% to 5% of polybutylene and the remainder made up to 100 per cent by weight with low-densi¬ ty polyethylene. The packaging is preferably made of a material consisting of from 15 to 25 per cent by weight of ethylene/vinyl acetate, 4 to 6 per cent by weight of soot, 3 per cent by weight of polybutylene, 3 per cent by weight of antistatic agent, and the rest made up with low-density polyethylene.

Figure 7 shows another possible embodiment of the packaging of a roll 1 of light-sensitive material according to the invention. The roll 1 consists of a hollow core 2, around which a sheet or a web 3 of a light-sensitive material is

wound. A starting strip or leader 4 is fastened at the end of the web 3. Near the two side edges 19 of the starting strip 4, on the outwardly directed surface, two elastic sheets or strips 20 of an elastic synthetic film, such as polyolefin, are fastened to the starting strip 4. The parts 21 in this case project over the side faces of the roll 1, while the parts 22 are arranged on the starting strip 4 in a prestretched state. In order to package the roll 1 in a lightproof manner, the side faces are covered with the aid of circular, lightproof discs, after which the starting strip 4 is wrapped around the roll, whereupon the projec¬ ting parts 21 of the strips 20 fold around the circumferen¬ tial edges of the discs as a consequence of the prestret¬ ched state of the strips 20.

Figure 8 shows the roll 1 from Figure 7, the packaging having been partly applied and the two strips 20 having been stretched. The side faces of the roll are covered with the aid of circular, lightproof discs 7. The projecting parts 21 of the strips 20 are in this case, as a result of the stretching of the film or elastic sheets 21, curled around the edge of the roll along the flange arranged there and pressed against the side face of the roll 1 and option¬ ally glued or fastened in another manner. A nonelastic paper band 23 is arranged over the parts 22 of the strips 20 which are fastened onto the starting strip 4, as a result of which the prestretched strip is enclosed between two layers which are nonelastic or of limited elasticity, specifically, on the one hand, the starting strip 4 of limited elasticity and, on the other hand, the paper band 23. The paper band 23 has a greater length than the pres¬ tretched strip 20. The paper band 23 consequently fixes the prestretched state of the strip 20. The parts 21 of the strips 20 which curl around the circumferential edge of the roll 1 are provided with perforations 24, which form a weakened line along which the packaging can be detached.

Figure 9 shows the roll 1 from Figures 7 and 8, after the packaging has been applied. The end of the starting strip 4

is provided with a tapering end or narrowed portion 25 which is fastened onto the outer surface of the roll 1 by a small piece of adhesive tape 26.

Figure 10 shows a roll 1 which is packaged in a manner which is particularly suitable for the lightproof packaging of rolls of relatively small dimensions. A starting strip 4 of limited elasticity is fastened at the end of the rolled- up web. One end of a sheet 27 of elastic material is arran- ged near the location where the starting strip 4 is faste¬ ned to the web of light-sensitive material. This elastic sheet 27 is wider than the roll 1 and projects with respect to the roll 1 and to the starting strip 4 at both side faces. The sheet 27 is shorter than the starting strip 4 and can be wound around the roll 1 just once. On top of the sheet 27 of elastic material, a sheet 28 of a nonelastic material, for example paper, is arranged at approximately the same location as where this sheet 27 is fastened onto the starting strip 4. Firstly, the ^' starting strip 4 is wrapped around the roll 1, whereupon the sheet 27 is pres¬ tretched and is wrapped around the roll 1, the nonelastic sheet 28 being fastened onto the prestretched sheet in order to fix the sheet 27 in the prestretched state. The nonelastic sheet 28 and the starting strip are approximate- ly of the same width as the roll 1 to be packaged. The prestretched sheet 27 which is situated between these sheets is wider and is arranged such that it projects at both ends of the roll 1. The projecting lateral edges 29 of the sheet 27 are not fixed by the sheet 28 and will seek to return to the unstretched state. When the sheet 27 is wound around the roll 1, the projecting parts 29 will consequent¬ ly fold around the circumferential edges of the roll 1, as is shown in Figure 11, the side faces of the roll being covered, for example with the aid of lightproof discs 7. The starting strip 4 is terminated by a tapering end or narrowed portion 25. The nonelastic sheet 28 is shorter than the starting strip 4 and has a length which is such that it overlaps the entire elastic sheet 27 but leaves the outer end of the narrowed portion 25 of the starting strip

4 free, so that it is simple for the user to grip the narrowed portion and to remove the packaging by pulling on the narrowed portion 25.

Figure 12 shows a front view of the roll 1 packaged in this way, the side faces being covered with the aid of flanges 30 which have a larger diameter than the roll 1. Due to the pretensioning, the projecting parts 29 of the prestretched sheet 27 will bend over the projecting diameter of the flanges 30, ensuring a lightproof seal in that area. The flanges 30 are in this exemplary embodiment provided with concentric bush-like projections 31, by means of which the packaged roll 1 can be placed in existing cartridge sys¬ tems. Other suitable flanges can be used for other cartrid- ge systems, in which case the diameter may be greater than, less than or equal to the roll diameter. A disc 32 of paper, for example, is arranged over the folded-over edges 29 of the prestretched sheet 27, which disc fixes the edges 29.