The present invention relates to the technical sector relating to packing flat articles, in particular ceramic articles, with particular reference to a packing method and the pack obtained with the method.

The invention concerns flat articles having a polygonal shape, in particular quadrangular, such as slabs and ceramic tiles, as well as materials which can also be arranged in stacks.

Methods are currently known for the packing of stacks of tiles having a square and/or rectangular geometry using prescored blanks that are slightly longer than the lateral extension of the stacks, comprising a central area to which four pairs of folds, lower and upper, are articulated by crease lines.

The central zone of the blank is wrapped on the lateral flanks of the stack and blocked at the ends by a "glue spot".

In phase relation with the folding of the central area on the sides of the stack, the lower and upper folds of the blank are folded on the lower and upper surfaces of the stack, for partial covering of the surfaces.

The folds which overlap at the corners of the stack are glued by as many "glue spots" in order to stabilise the configuration perpendicularly to the central area of the blank.

Thus, in this way a perimeter band is defined, for protection of the lateral sides of the stack and the corresponding corners, as well as of the edges of the upper and lower surfaces of the stack.

This method is not recommended for the packing of stacks of tiles of medium/large dimensions as the large longitudinal size of the blanks makes the operations for folding on the surfaces of the tiles extremely difficult.

In such a case, also extremely problematic is the adjusting of the central zone of the blanks during the step of superposing and closing them.

Also notable is the fact that the small thickness of the blanks can generate damage thereto during the folding step on the lateral flanks of the stack.

To this can be added the problems relating to tile format change, which requires a particularly large storage zone provided with a number of blank formats that is equal to the number of tile stack formats to be packed.

A no-less important problem concerns the limitation of maximum longitudinal dimensions of the blanks both as a result of the technical limitations of the packing plants and the difficulties of handling and storage of the blanks themselves.

Purely by way of example, for the packaging of a square tile side of 1000 mm and thickness 12 mm a blank of 4000 x 115 mm would be required, which with the plant engineering techniques available today would not be feasible because the maximum permissible dimensions are approximately 2500 mm .

Document WO2007/148183 discloses a method for the production of blanks with the aim of reducing the overall dimensions of the storage area.

This method provides for the predisposing of a structure in a packaging material provided with a series of weakened lines for folding about at least a plate-shaped article; the predisposition providing, in order, the following operational steps:

• preparation of at least a length of packing material for each side of the plate-shaped part to be packaged;
• weakening of each length along at least two predetermined fold lines;
• the consecutive joining of the lengths such as to define a frame having a polygonal shape, the shape of which reproduces the polygonal shape of the form of the article to be packaged.

In particular, the realization of each length comprises the following steps:

• providing two or more supply panels in series;
• consecutively connecting the panels to form a continuous strip which extends predominantly along a predetermined development direction;
• cutting the continuous strip transversally to the development direction thereof, according to a set measurement depending on the side of the polygonal shape of the article to be packaged.

Further operational steps are included, for realising tabs for connection between the various sections, and for the insertion of a protection insert for the sides of the article, along the lengths.

The method proposed by document WO2007/148183 essentially enables the reduction of the overall dimensions of the storage area; it is however not recommended in the case of packaging of relatively large tiles as it requires the assembly of a plurality of pieces of extremely small thickness.

In this case the squaring of the frame is extremely difficult and can adversely affect the realization of the perimeter protective band of the stack of tiles or the individual tile.

The absence of reference points for the squaring of the frame leads to serious problems during printing in the connecting areas of between lengths, especially in the case of the use of bar codes identifying the product, not to mention the damage to the commercial aspect of the package obtained.

Regardless of the size of the tiles, however, the perimeter frame obtained does not continuously protect the longitudinal edges of the stacked tiles due to the presence of corresponding slots resulting from the assembly method of the frame, obtained starting from a plurality of portions at least equal in number to the number of sides of the tiles.

Document EP 1 323 645 discloses a packaging for rigid articles in which the packaging covers only peripherally, and over a parital area of border, two or three sides of stacked packs of rigid bodies such as tiles. The packaging can be L-shaped, covering two sides, or U-shaped, covering three sides, with or without end flaps. The packaging can be overlaid and glued and may include safety straps, and can be glued between overlaid peripheral corners and bottom surfaces of a bottom-most tile of the stack of tiles.

Document FR 2 621 895 discloses a method of packaging objects such as, for example, dismantled furniture defining an assembly of parallelepiped shape comprising two main faces and four lateral faces surrounding the main faces, in such a way as to define a border of predetermined height. This method establish that the corners of the border are covered by means of cardboard angle bars whose branches, overlap in such a way as to define a frame around the assembly to be packaged, this frame being held by means of hooping ties, made of polypropylene in particular, and then a heat-shrink film is placed around the assembly thus framed and this film is then shrunk.

Document EP 0 994 043 discloses a package for packs of flat piled objects, in particular for ceramic tiles, comprising two half-blanks made of cardboard and identical, each of which comprises two flaps joined along a fold line. Each flap is destined in use to follow a profile of a flank of a pack of tiles. A top flap and a bottom flap are joined by fold lines to each flap and will in use be superposed on a perimetral part of, respectively, a topmost and bottom-most face of the pack of tiles. A tongue is joined by a fold line to one of the two flaps. The tongue of one half-blank is destined to be superposed on an end of another half-blank. A package of the type described enables a relatively simple and rapid packaging of tiles of varying formats.

The aim of the present invention is to obviate the above problems by providing a method for packaging flat articles, and a package obtained with the method, which enables extremely effective protection of the articles, as well as the corresponding edges, in particular during the steps of storage and/or transport.

A further aim is to provide a method and a pack capable of limiting the use of packing material and glue with respect to known methods.

Additionally a method is provided, and a pack obtained with the method, which can be applied to flat articles of relatively large dimensions, without limitation deriving from the blank-cutting plants.

The above-mentioned objects are obtained with a method for packing at least a flat article, according to claim 1.

According to further ways of carrying out the method of the invention, the method comprises one or more of the following characteristics, considered singly or in combination:

• stabilising of the superposing zones comprises binding the article by means of at least two first straps loop-wound on the covered lateral flanks of the central regions of the blanks, with each first strap interesting, for each surface of the article, two corner superposing zones and a second lateral superposing zone;
• stabilising of the superposing zones comprises binding the article by means of at least three second straps loop-wound on the lateral flanks not covered by the central regions of the blanks, with each second strap interesting, for each surface of the article, two corner superposing zones or two second laterally superposing zones;
• stabilising of the superposing zones comprises using adhesive means interposed between folds or flaps of the blanks nvolved in the superposing;
• during the step of supplying the blanks, each thereof comprises four cut lines, each of which separates an upper or lower flap from the corresponding upper folds or lower folds; the cut lines preferably diverging distancingly from the central region;
• the flat article comprises a tile or a ceramic slab, or a stack of tiles and/or ceramic slabs.

The aims of the invention are also attained by means of a pack, according to claim 7.

According to further embodiments the pack of the invention comprises one or more of the following characteristics, considered singly or in combination:

• the stabilising means comprise at least two first straps loop-wound on the covered lateral flanks of the central regions of the blanks with each first strap interesting, for each surface of the article, two corner superposing zones and a second lateral superposing zone;
• the stabilising means comprise at least three second straps, loop-wound on the lateral flanks not covered by the central regions of the blanks, with each second strap interesting, for each surface of the article, two corner superposing zones or two second laterally superposing zones;
• the stabilising means comprise adhesive means interposed between folds or flaps of the blanks involved in the superposing;
• each blank comprises four cut lines, each of which separates an upper or lower flap from the corresponding upper folds or lower folds, the cut lines preferably diverging distancingly from the central region;
• the flat article comprises a tile or a ceramic slab, or a stack of tiles and/or ceramic slabs.

The characteristics of the invention will be pointed out in the following are described by way of example some preferred but not exclusive embodiments, with reference to the accompanying drawings in which:

• figure 1 is a perspective view of a schematic sequence diagram of the method for packing of a stack of tiles;
• figure 2 shows, in enlarged scale, an exploded perspective view of the stack of tiles and the corresponding packing blanks;
• figures 3A, 3B show, in enlarged scale, corresponding perspective views of the packing blanks of figure 2;
• figure 4 illustrates a plan view of a blank shown in figures 3A, 3B;
• figures 5, 6 show, in enlarged scale, corresponding perspective views of two embodiments of the pack obtained with the present method;
• figures 5a, 5b illustrate, in an enlarged scale, details Y1, Y2 indicated in figure 5;
• figures 6a, 6b show, in enlarged scale, details Y3, Y4 shown in figure 6.

With reference to the above drawings, general references 3, 4 denote a pair of blanks made of a packaging material, e.g. cardboard, each comprising a central region 5; an upper flap 6 connected to a first side of the central region 5 by means of a first crease line; a lower flap 7 connected to a second side, opposite the first side, of the central region 5 by means of a second crease line; a first lateral flap 8, connected to a third side of the central region 5 by means of a third crease line, identifying a free end 8a opposite the third crease line; a pair of first folds, an upper fold 80 and a lower fold 81, connected by crease lines to two sides of the first lateral flap 8 which folds 80, 81 are opposite one another and perpendicular to the third crease line; a second lateral flap 9 connected to a fourth side, opposite the third side, of the central region 5 by means of a fourth crease line, identifying a free end 9a opposite the fourth crease line; a pair of second folds, an upper fold 90 and a lower fold 91, connected by crease lines to two sides of the second lateral flap 9, which folds 90, 91 are opposite one another and perpendicular to the fourth crease line.

The proposed method for packaging at least a flat article 2 comprising two opposing sides, upper and lower, in a quadrangular geometry and a plurality of lateral sides, to comprise the following steps:

• supplying the pair of blanks 3, 4;
• covering two opposite lateral flanks of the article 2 with the central region 5 of each blank 3, 4;
• partial covering of the opposite surfaces of the article 2 with the upper flap 6 and lower flap 7 of each blank 3, 4;
• covering the remaining lateral flanks of the article 2 with the first and second lateral flaps 8, 9 of each blank 3, 4 such as to superpose the free ends 8a,9a of the lateral flaps 8, 9 of a blank 3 with corresponding free ends 8a, 9a of the lateral flaps 8, 9 of the other blank 4, such as to identify two zones L₁ of first lateral superposing;
• partial covering of the opposite surfaces of the article 2 with the first folds 80, 81 and the second folds 90, 91 of each blank 3, 4, such as to define, for each surface of the article 2, four zones A of corner superposing in which one of the flaps, upper 6 and lower 7, is arranged superiorly or inferiorly of one of the first folds 80, 81 or the second folds 90, 91, and two zones L2 of a second lateral superposing, adjacent to the zones L₁ of first lateral superposing, in which the first folds 80, 81 and the second folds 90, 91 of a blank 3 are arranged superiorly or inferiorly of the corresponding first folds 80, 81 and second folds 90, 91 of the other blank 4;
• stabilising of the superposing zones L₁, L₂, A by stabilising means 10, 11.

The flat article 2 can comprise either, a ceramic tile or slab, or a stack of tiles and/or ceramic slabs.

In the step of supplying the blanks 3, 4, each thereof comprises four cut lines 12, each of which separates an upper or lower flap 6, 7 from the corresponding upper folds 80, 90 or lower folds 81, 91, as can be deduced from figures 3A and 3B.

As shown in detail in figure 4, the cut lines 12 are preferably divergent, distancingly from the central region 5 such as to facilitate realisation of the corner superposing zones A.

In a preferred embodiment, the stabilising of the superposing zones L₁, L₂, A comprises binding the article 2 by means of at least two first straps 10 for example plastic straps loop-wound on the lateral flanks not covered by the central regions 5 of the blanks 3, 4.

In this case each strap 10 interests, for each surface of the article 2, two corner superposing zones A or two second laterally superposing zones L₂, as shown in figure 5.

In a further embodiment, the stabilising of the superposing zones L₁, L₂, A comprises binding the article 2 by means of at least three second straps 11 for example plastic straps loop-wound on the lateral flanks not covered by the central regions 5 of the blanks 3, 4.

Consequently, each strap 11 interests, for each surface of the article 2, two corner superposing zones A or two second laterally superposing zones L₂, as shown in figure 6.

In particular a pair of straps 11 loop-closes on the flaps, upper 6 and lower 7, and on the flaps, first 8 and second 9, of the respective blanks 3, 4, while the remaining strap 11 loop-closes on the opposite surfaces of the article 2 and on the respective lateral superposing zones, first L₁ and second L₂.

In a further embodiment, the stabilising of the superposing zones L₁, L₂, A can comprise using spots of glue interposed between folds 80, 81, 90, 91 or flaps 6, 7 of the blanks 3, 4 involved in the superposing.

In the accompanying figures, reference is made to the packing of a stack 2 of ceramic tiles having a square geometry; it is understood that the proposed method can be applied to any flat quadrangular article that is also rectangular or has at least a pair of parallel sides, possibly two pairs of parallel sides.

The longitudinal extension of the pair of blanks 3, 4, evaluated along the longitudinal direction of the central region 5 and the adjacent side flaps, first 8 and second 9, may therefore be the same, identifying specular blanks; or they can be different.

However, in the latter case it is preferable to maintain the same longitudinal extension as the central region 5 of each blank 3, 4, to cover the two opposite lateral flanks 2 of the same longitudinal extension, thus appropriately modifying the longitudinal extension of the lateral flaps 8, 9 of each blank 3, 4.

In particular, a first blank 3 can be provided having side flaps 8, 9 exhibiting a same longitudinal extension, and a second blank 4 provided with lateral flaps 8, 9 having a same longitudinal extent, the latter, however, being different from the corresponding lateral flaps 8, 9 of the first blank 3.

In this case, depending on the extent of the lateral superposing zones, first L₁ and second L₂, due to the overlap of the side flaps 8, 9 and the corresponding upper flaps 80, 90 and lower 81, 91 of the blanks 3, 4, it is possible to use a same format of blanks 3, 4 for a wide range of sizes of articles 2.

According to requirements it is also possible to provide different longitudinal extensions to the lateral flaps 8, 9 of a blank 3, 4 or both.

The stabilising of the overlapping zones L₁, L₂, A can be achieved, in an advantageous way, with the help only of two or three plastic straps per pack, i.e. without any aid with the use of glue figures 5, 6.

From the foregoing it clearly emerges how the proposed method for packing flat articles, and the corresponding package obtained therewith, extremely effectively protects the articles and the corresponding edges, in particular in the of storage and/or transport steps.

Effective protection of the lateral flanks and the corners of the flat article is in fact ensured, together with extended portions of the surfaces, thanks to the coupling of a pair of blanks, which when suitably folded define corresponding half-shells having a "U"-shaped cross-section.

The proposed method and the associated package are particularly recommended also in the case of packing flat articles of relatively large dimensions, where the thicknesses of the articles and consequently of the corresponding blanks become extremely small.

Unlike the method disclosed in document WO2007/148183, the proposed method and the associated pack do not suffer from the problems caused, on the one hand, to the squaring of the frame formed by a plurality of portions of reduced thickness, and on the other hand to the difficulty of printing in the areas of connection of the lengths themselves.

Using blanks with different longitudinal extensions of the side flaps, by varying the extension of the lateral superposing areas due to the superposing of the lateral folds and the corresponding top and bottom folds, the blanks can be adapted to a wide range of sizes of articles to be packed.

The proposed method and the associated pack therefore enables limiting the use of packaging material and glue in comparison with the prior art.