WO2000055050A2

WO2000055050A2 - Packaging elements

Info

Publication number: WO2000055050A2
Application number: PCT/EP2000/002226
Authority: WO
Inventors: Catia Bastioli; Vittorio Bellotti; Maurizio Buono
Original assignee: Novamont S.P.A.
Priority date: 1999-03-15
Filing date: 2000-03-14
Publication date: 2000-09-21
Also published as: WO2000055050A3; ITTO990196A1; IT1308431B1; AU3811000A

Abstract

A packaging element in which an object to be packaged is located, comprising blocks or inserts of biodegradable expanded material caused to adhere to a sheet in positions such as to ensure, when the box is closed, the formation of protection and retaining regions for holding the object to be packaged, the said blocks being located on the outside and/or inside the box when the box is closed.

Description

Packaging elements

Field of the invention

The present invention relates to packaging elements which can be composted or pulped, provided with shock-protection inserts or blocks, and packages obtained utilising such elements .

State of the art

Disposable packages have been used for decades to protect fragile objects such as glass, electronic equipment and related ancillaries during transport and handling. The type of material used for packaging has evolved over the years . Packaging materials for the protection of fragile objects have included woodchips, used paper and synthetic materials such as polystyrene and polyurethane .

Two kinds of packaging have found wide use: pre-formed packages and packages which acquire the shape of the package at the time of packaging. A widely used package of this latter type uses foamed small potato pieces in the form of granules or other shapes made of polystyrene . A conventional system widely used for packaging includes blocks, sheets and cubes cut and/or moulded to the shape of the fragile structures to be packaged. Packages produced in the various shapes are able to guarantee excellent cushioning properties due to the excellent characteristics of polystyrene. For both types of packaging using polystyrene the major disadvantage is the difficulty of recycling the packaging after having arrived at the final consumer, taking into account the low weight and high volume occupied and the fact that the product is not biodegradable and can only be recycled at high cost.

Anothe negative aspect lies in the high energy content of polystyrene in that it is derived from petroleum, with respect to products from renewable resources . Because of their biodegradability, anti-static properties and low energy content, and capacity not to contribute to the greenhouse effect, materials from renewable resources, and in particular materials based on starch, represent a valid alternative.

Loose fillers based on expanded starch or agglomerates obtained from particles of expanded starch are commonly used as protective materials in packages for fragile objects. A disadvantage of this packaging system is due mainly to the fact that loose fillers, or similar shapes, being mobile, are not able to prevent possible relative movements of the object within the package, with consequent possible breakage thereof . The quantity of expanded material to be utilised is moreover significant .

European Patent Application EP-0 696 611-A2 describes the preparation of loose fillers, sheets, injected products and agglomerable particles of particularly low density and with high strength. European Patent Application EP-0 667 396-A1 and EP-0 696 612-A2 relate to the agglomeration of extrusions of starch of different shape and dimensions by the use of a ccooaattiinngg ooff wwaatteerr aanndd//oorr hheeaatt ttoo oobbttaaii:n preformed expanded structures which are connected together.

Description of the invention

The object of the present invention is to simplify packaging systems by the use of composite systems which involve the coupling of materials of different nature, which are biodegradable and recyclable with the same technology in such a way as to simplify disposal, and connected in such a way as to make the packaging process simple and economic and to minimise the quantity of packaging material utilised.

In view of this object the packaging elements of the invention are constituted by a sheet of ribbed cardboard having a shape such as to develop into a closed box by folding, into which the object to be packaged is to be placed and, adhering to the cardboard sheet, blocks or inserts of expanded material based on polysaccharides , preferably starch and its mixtures , and synthetic or natural thermoplastic polymers , and having shapes and dimensions such that when located in position and the box closed, they provide protection zones for holding the object to be packaged in position. i

Expanded blocks are located outside or inside the box, when closed, and possibly in both positions.

The blocks are made to adhere to the cardboard sheet utilising adhesive agents constituted by water, aqueous adhesive emulsions and/or by applying heat.

The blocks can be obtained according to various methods by cutting them, for example, from a sandwich of several layers of expanded strands connected together by means of water and in which the first layer is fixed to the moistened cardboard support . The blocks can be obtained from cubes by agglomerating, hot, several layers of expanded sheets or expanded particles surface treated with a melt based on aliphatic polyesters, or moistened with water, or other known methods .

The particles can be obtained by treating with microwaves, or with infra red, as well as using conventional extrusion methods . The blocks can have different geometric shapes such as, for example, cubic, rectangular or prismatic shapes. The shape is chosen essentially in dependence on the shape and dimensions of the object to be packaged. The blocks are fixed to the surface of the card, before closure of the box, utilising a manual or, preferably, robotic system with the inserts being located at the points of greatest stress for the item to be packaged.

In Figures 1 to 3 there are shown various examples of elements according to the invention.

The packaging of the article can thus be obtained in a completely automatic manner simultaneously with the closure of the box.

The packaging line may include the production of expanded blocks or inserts by means of: extrusion, sintering, microwaves, infra-red, wafer, injection or by agglomeration of expanded particles to produce finished pieces or cubes from which the inserts can be formed or by means of injection of the finished inserts themselves .

The inserts are of dimensions and density, and relative rigidity and mass such as to ensure damping of vibrations due to external or internal forces of an impulsive, cyclic or otherwise unpredictable character both as far as frequency and intensity is concerned. Moreover, the inserts are fixed to the cardboard support in positions such as to permit the product to be held in. place by friction against relative movement with respect to the package .

The application of the inserts to the open cardboard box can take place via a loader which contains the inserts already pre-arranged for application. During deposition of the inserts or before this stage it has to have an adhesive agent such as water, aqueous or other emulsions applied by spraying, and/or heat.

Subsequently or simultaneously it is possible to provide a pressure stage sufficient to guarantee adhesion of the inserts to the cardboard in a permanent manner, and a possible air-blowing stage if it is necessary to obtain rapid drying. The box can then be closed about the structure to be packaged.

By varying the shape of the inserts it is possible also to create with the inserts themselves, in the case of boxes which are not particularly deep, actual dividers if the product to be packaged is not made of one piece.

As far as disposal after use is concerned there are various possibilities. The inserts are potentially soluble or at any rate dispersible in water. They can be pulped together with the cardboard of the box, becoming an adhesive for the cardboard itself . As far as transport of /the packaging materials after use is concerned, this can become extremely simple by spraying a small amount of water onto the inserts in such a way as to cause collapse of the expanded inserts . However, since the expanded inserts are easily cut and glued with water they can become a material for construction more versatile than Lego. The package can therefore contain within it a tool for removing the inserts and a leaflet of instructions. Moreover, the product may easily be disposed of down the drain or, better, via a container for moisture and composting.

The inserts are constituted by modified and unmodified polysaccharides of various type (for example modified cellulose such as esters and ethers of cellulose) and preferably, by starch or its mixtures with natural or synthetic thermoplastic polymers containing possible plasticisers, fire retardants, animal repellent, lubricant, natural fibres such as cellulose, woodchips, rice husks, agricultural waste of fibrous nature, jute, straw etc, synthetic fibres such as polyester and polyamide preferably biodegradable or inorganic fibres such as glass etc . and fillers of various nature up to a total of 70% by weight. The expanded elements as such or agglomerates thereof may be combined in sandwich structures with wood, paper, cardboard, fabrics, or plastics all of which may be biodegradable, soluble, or insoluble. During agglomeration, moreover, the expanded elements may be agglomerated together with cellulose fibres, woodchips or other natural and/or synthetic fibres. The sandwich systems may be formed using layers of different material to form blocks. When using paper and/or card intercalated with layers of expanded material it is possible to construct elements having very different properties by cutting the elements in the longitudinal or transverse direction of the sheet. Moreover, the cardboard elements may have different profiles such as saw tooth, trapezoidal or rounded where each saw tooth, trapezoidal or rounded channel can receive a strand of expanded starch. In this way it is possible to construct panels which if cut transversely have an alveolar form.

It is also possible, although this constitutes a less preferred alternative, to fix the blocks of expanded material to a pre-formed box by inserting them into positions where the object to be packaged is stressed, so as to avoid possible movement thereof in the package .

In this case, too, whenever the blocks are fixed at least in part to the outside of the box, they will be fitted into a second box with the blocks in contact with the walls of this latter.

Several embodiments of the packaging elements according to the invention will now be described, purely by way of example .

Example 1

Strands obtained by extrusion are cut during the expansion process by means of a shear type cutter head so as to obtain expanded cylinders having a length of about two metres and a diameter of about 10 mm. These are guided, once outside the extruder, by a transport system constituted by a tube with an ejector at the end so as to create a depression downstream thereof . The extrusions are then collected in a hopper which constrains them along their length. From this site, via a controlled aperture positioned in the lower part of the hopper, the strands are caused to adhere to damp cardboard to form a first layer. By means of spray nozzles the surface is lightly wetted. A second layer is then formed and a new phase of surface moistening performed. Finally an expanded sandwich is obtained constituted by individual strands joined together by water which utilises cardboard as a support . With this process sheets and corner blocks for packaging are obtained.

Example 2

(A) Packaging of an object in the form of a parallelepiped utilising prismatic blocks of suitable dimensions as protective elements, made up of expanded strands connected together using water and obtained by cutting a single agglomerate of strands previously formed according to the procedure already described in example 1.

The packaging of a casing of a desktop type computer is considered. Taking a sheet of reinforced ribbed cardboard the expanded elements are applied according to the diagram of Figures 1 and 2. The computer is placed onto the support bases and the system closed. All is then put into a box.

(B) As, for example (A) but, in place of the parallelepiped of strands, parallelepipeds cut into cubes obtained from expanded particles of dimensions 2 mm in diameter and 3 cm in average length are used, surface treated by hot agglomeration with hot melt based on aliphatic polyester.

(C) As example (A) but the parallelepipeds are derived from several layers of ribbed expanded sheet .

Example 3

As example 2 but replacing the blocks obtained from expanded strands with blocks obtained by sintered particles . Example 4

As example 2 but replacing the blocks obtained from expanded strands with expanded blocks obtained using microwaves .

Example 5

As example 2 but replacing the blocks obtained from expanded strands with blocks expanded using IR techniques .

Example 6

As example 2 but replacing the blocks obtained from expanded strands with blocks expanded by injection moulding.

Example 7

Two sheets of cardboard are joined by a thin sheet of expanded starch. The laminated cardboard can be used in a manner similar to that of ribbed cardboard.

Example 8

As for example 7 but, in place of expanded sheets, expanded particles of 2 mm in diameter are joined to the cardboard. The cardboard thus has improved structural properties .

Example 9

Creation of a packaging corner starting from /biodegradable blocks as from example 2. This is relevant (Figure 3) to the packaging of an electrical domestic machine which necessitates eight corners at the ends so as to be manipulated by machine hooks . The box will have the blocks disposed internally according to the configuration of the drawing. The blocks will be adhered to the cardboard using water. In the drawing only the blocks relating to the corners are shown for clarity and not the other protective parts .

Example 10

Blocks of sintered particles mechanically worked by removal of material for the purpose of obtaining protective transit packaging pads are used (Figure 4) as in the. drawing.

Claims

1. A packaging element constituted by a sheet of ribbed card with a shape which can be developed by folding into a closed box, in which the object to be packaged is placed, including blocks or inserts of biodegradable expanded material having such shape and dimensions and being caused to adhere to the sheet in such positions as to form, when the box is closed, protection and fixing zones for the object to be packaged, the said blocks being located outside and/or inside the box when the box is closed.

2. An element according to Claim 1 , in which the blocks or inserts of biodegradable expanded material are made of a material based on polysaccharides .

3. An element according to Claims 1 and 2 , in which the blocks or inserts are located at the points of greatest stress on the objects to be packaged.

4. An element according to Claims 1 to 3 , in which the expanded blocks or inserts are formed by a sandwich of layers of expanded strands formed together using water.

5. An element according to Claim 4, in which the first layer of strands is adhered to a sheet of moistened card.

6. An element according to Claims 1 to 3 , / in which the expanded blocks or inserts are formed into cubes by agglomerating expanded particles or several layers of expanded sheets .

7. An element according to Claims 1 to 6, in which the expanded inserts or blocks are formed by injection moulding.

8. An element according to Claims 1 to 7, in which the expanded inserts or blocks are formed from particles expanded by means of microwaves or by infra-red radiation.

9. An element according to Claims 1 to 8 , in which the expanded blocks or inserts have a cubic, parallelepiped or prismatic shape .

10. An element according to Claims 1 to 9, in which the expanded blocks or inserts are caused to adhere to the cardboard sheet by using adhesive agents chosen from water, aqueous emulsions and/or the application of heat.

11. An element according to Claims 1 to 10, in which the shape of one or more of the expanded blocks or inserts is varied in such a way as to form divider elements .

12. An element according to Claims 1 to 11, in which the material of the expanded inserts or blocks is chosen from starch and its mixtures with synthetic or natural thermoplastic polymers, esters and ethers of cellulose.

13. Packaging including an element according to Claims 1 to 12, folded to form a closed box containing the object to be packaged, in which the expanded blocks or inserts are located outside the box, the said box being enclosed in a second box.

14. A box for packaging including blocks of expanded material based on polysaccharides, fixed to the interior and/or exterior of the box in positions where the object to be packaged is stressed, and acting as retainers to hold it in its position against possible movements within the package .

15. A box according to Claim 14 , in which when at least some of the blocks of expanded material are fixed into the box, the box is inserted into a second box with the blocks in contact with the walls of this latter.

16. A box according to Claims 14 or 15., in which the material forming the blocks is chosen from starch and its mixtures thereof with natural and synthetic thermoplastic polymers and esters and ethers of cellulose .

17. A process for the disposal after use of packages formed from elements according to Claims 1 to 10 , in which the package is treated with water for the purpose of dissolving or dispersing the expanded blocks in water, and the aqueous solution or dispersion thus obtained is pulped together with the cardboard of the box.

18. A process for the recovery after use of expanded blocks comprising the elements of Claims from 1 to 12, in which the blocks are cut from the elements and utilised as structural materials for play.