CN1005470B - Laminated material and method for manufacturing the same - Google Patents

Abstract

The presnt invention relates to a laminated material which comprises a carrier layer of paper or cardboard and an outside layer of extruded polythene applied to one side of the carrier layer. To the other side of the carrier layer is applied a first binder layer of polythene and a layer of aluminium foil placed against the binder layer. A second binder layer of EAA is provided for the bonding together of the aluminium foil with an inner polythene layer which has been produced by blowing and which has a substantially higher modulus of elasticity and strength than the slot-extru-ded polythene layer . The invention also relates to a method ~or the manufacture of the laminate by making use of the heat content of the first slot-extruded binder layer of polythene for heating up the second binder layer of EAA to such a temperature that an effective bonding on the aluminium foil is obtained.

Description

Laminated foil and its manufacture method

The present invention is relevant a kind of laminated material that has mechanical properties strength and available heating power soldering and sealing and have anti-oily characteristic and neutral taste.

Aspect packing technique, can often use the laminated material of labyrinth, for utilizing the optkmal characteristics of each homogenous material, and these characteristics are integrated, make to be packaged to be optimum combined material, or make special goods obtain optimum packing.Therefore; we know that paper, cardboard, rigidity foaming plastic plate etc. all can make packing that rigidity is arranged, as long as these materials Zhe song; just can obtain the packing container of permanent shape, they can provide the favorable mechanical protection to the article that are kept at the inside.But, as everyone knows, paper stock and cardboard be all non-watertight, grease resistance and ventilative not, so paper material needs and other material is laminated just can obtain ideal effect.

The laminated foil of Zhi Zaoing in this way, its structure can be quite complicated, because above-mentioned laminated thin sector-meeting contains a lot of thin layers, because these thin layers need superposition, manufacturing expense just can not be cheap.We also know, can push plastic material simultaneously, can obtain material cohesive preferably so on the one hand, on the other hand, can be in same manufacture process, produce and contain the plastic sheeting of moulding layer more than two-layer or two-layer.

Need to produce paper, cardboard in the present circumstance or play foamed polystyrene etc. and be the packing of carrying layer laminated foil, this illustrates that the packing box by this laminated foil manufacturing can be become permanent shape by Zhe, provides the favorable mechanical protection to the article of the inside.In addition, laminated foil must not can transflective liquid, can not absorb the moisture and the liquid that contacts with packing box outside, the inside of packing box also should antiseepage liquid, and can adopt heating with pressure method the plastic layer hot weld to be in the same place, formation has the integral body of mechanical strength.When sheathing foodstuff, with food directly contact in mould layer, its special odor should be very low.Moulding layer in this must have enough intensity and toughness, and its toughness when standing fold and being shaped to the pressure of material, unlikelyly cause breaking of plastics.Also have laminated foil that one gas barrier should be arranged, that is to say it is the material that one deck prevents gas penetration, and only be exactly aluminium foil layer.Therefore, using different adhesive layers adheres to each other various material.

The present invention also is simultaneously the manufacture method of relevant a kind of laminated foil material, and the inside and outside two sides of this material has one deck aluminium foil and one deck thermoplasticity artificial resin respectively.Traditionally, when making this laminated foil material (the lamination scraps of paper), two kinds of methods are arranged in a broad sense.

A kind of method is called as dried laminating, at layered material (sublevel), and for example on the film that artificial resin or similar substance are made, coated with adhesive, in addition dry, again this sublevel is sticked on the surface of main stor(e)y or other layered materials.

Another kind method as shown in Figure 3, is called the extruded layer platen press, and the film of synthetic resin of 300 ℃ of molten conditions of being drawn by extrusion mould A is injected, and the synthetic resin material of this injection forms a coat of synthetic resin on the surface of aluminium foil.

When coming connection with wrapping of piece with the laminated foil material of conventional method manufacturing, can make article that very abnormal smell is arranged, or destroy the taste of article, this variation takes place to packing long preservation or the food packed through regular meeting in this unsuitable change under higher temperature.

This is because this class with doing the thin slice that laminating is made, between the aluminium foil layer and synthetic resin layer on the packing container inner surface, has layer of adhesive by wash-out.

On the other hand, use the extruded layer platen press, can make synthetic resin material itself produce oxidation product (carboxyl group), form another synthetic resin layer, this material can produce unusual odor and destroy food taste.

When making the packing container of preserving drink, itself must have sufficient intensity this packing container, and this synthetic resin layer will stick on the inner surface of aluminium foil securely simultaneously, and the laminated foil container can be out of shape, and the drink that is packaged in the inside can not leak out yet.In order to make synthetic resin stick on the aluminium foil securely, just need when reaching more than 300 ℃, it be injected into as polyvinyl resin, the resin that high temperature injects down can closely stick to aluminium foil surface, before aluminium foil surface forms shallow layer, can contact with air relatively for a long time, therefore produce a large amount of oxidation products.On the contrary, prevent to produce oxidation material if reduce the temperature of synthetic resin material, then adhesion will weaken, and the service behaviour of packing container can reduce.

Oxidation product in the synthetic resin layer can infiltrate in the packaged article gradually by wash-out, particularly under high-temperature condition, can accelerate elution speed.

Because this reason, use packing container not heat, and the packing container with such defective want long preservation then rather difficult to the food of aroma and flavor sensitivity by the laminated foil material of conventional method manufacturing.

According to the inventive method that above-mentioned variety of issue proposes, make film of synthetic resin stick to the surface of aluminium foil securely, and when manufacturing is suitable for the laminated foil material of sheathing foodstuff, will reduce a large amount of oxidation products generations.

The present invention proposes a kind of rational method of producing this material and having this material of feature described in claims.

Be to description that the present invention did below with reference to each accompanying drawing.

Fig. 1 represents how variant material synusia combines togather.

Fig. 2 is the simplified schematic diagram of manufacture process.

Fig. 3 represents how to blow the method for being made of film polyethylene and ethylene acrylic acid (EAA).

Fig. 4 is a sketch, and expression belongs to the process of the manufacturing laminated foil material of the inventive method.

Fig. 5 is a profile, illustrates the manufactured goods of the laminated foil material that is used for sheathing foodstuff.

Fig. 6 is a profile, illustrates the production process of conventional production methods, the 1st, and main stor(e)y, the 2nd, aluminium foil, the 3rd, synthetic resin, the 4th, mould, 5 and 6 is cylinders, the 7th, film of synthetic resin.

Laminated foil with the inventive method is made can be constituted by several different materials, introduces the combination of producing a kind of material that is suitable for packing liquid food below.Fig. 1 illustrates the method for laminated foil of the present invention.Fig. 1 represents to scribble in advance the paper of polyethylene layer 2 or the carrying layer 1 of the scraps of paper, walks around cylinder 8, enters two " folder mouth " districts that work in coordination between the chilling roll 9 and 8 that compresses downwards.Aluminium foil 4 is introduced between these two cylinders simultaneously basically corresponding to sheet 1.Between the aluminium foil of introducing 4 and carrying layer 1, be the plastic sheeting that is squeezed out by groove, its production method is plastic molting, and the groove by mould pushes out (groove extrusion) again.Uncured thermal plastic film 3 is pressed between carrying layer 1 and the aluminium foil 4 by cylinder 8 and 9, and between plastic sheeting 3 and the carrying layer 1 and produced mechanical adhesion power between plastic sheeting 3 and aluminium foil 4, meanwhile, plastic sheeting 3 coolings also are fixed up.But, in this case, the mixing extrusion film 5(that is made up of two layers of plastic is the plastic layer 7 and the plastic layer 6 formed of polyethylene layer by blowing of ethylene acrylic acid (EAA) class in advance) also be introduced between cylinder 9 and 8.Plastic layer 6 and 7 mixes when pushing out, and it is exactly to make between blowing plastic outer layer 6 and the aluminium foil 4 in same lamination production process that good adhesiveness remaining issues is arranged each other, also good adhesion will be arranged.Under described situation, plastic sheeting 3 by the groove extruding is bonded on the carrying layer 1 aluminium foil layer 4, because the thermal conductivity of aluminium foil is better than the paper stock of carrying layer 1, so in this lamination process, the plastic sheeting 3 contained most of heats that push through groove send aluminium foil 4 to.When plastic sheeting 3 coolings and solidifying, aluminium foil layer 4 is heated, and the transfer of heat of plastic layer 3 is to the EAA layer 7 that mixes extruding plastic film 5, about 93 ℃ of its seam temperature.Could go out the extruding plastic film extrusion because at least also will be heated to 300 ℃, so the heat that need be dispersed is just quite big.If extruding plastic layer 3 selected temperature and thickness are correct, the heat that reaches EAA layer 7 is with enough seam, and the temperature of EAA layer 7 rises to and is higher than 93 ℃, melts surfacewise towards the one side of aluminium foil layer 4, just be bonded in above the aluminium foil layer 4 after cooling.Therefore, whole laminated foil combination is to finish in same lamination process, and having only carrying layer 1 is to use the special procedure plastic-coated in advance; Also have another operation of film 5 usefulness to mix in addition to push and blowing is made.Very reasonable with method of the present invention, so can obtain excellent economic, reason is the heat that the present invention utilizes unique extruded lamination lamella 3, and the top layer 7 of mixing extrusion film is heated to the seam temperature, has avoided two kinds of different lamellose extruding.

According to the method for the regular manufacturing laminated foil of the present invention, be included on the aluminium foil layer 4 and be coated with plastic layer, in other words, come the nexine of ironed of producing zone with a groove extrusion of separating.Knew already, and, just must come extruded polyethylene in the temperature that is not less than 300 ℃ if polyethylene layer is sticked on the aluminium foil securely, and material meeting polarity oxidation under this temperature, in other words, run into liquid or by what method got wet as fruit polyethylene, that just can not carry out hot weld.

The modern packaging method is by the fluid column seam, if therefore there is polar substances in packing container inside, just seam in this way.Ways of addressing this issue, be the polyethylene layer outside that squeezes out at high temperature, squeeze out layer of polyethylene with lower temperature again, if the temperature of this low temperature extruding remains on below 290 ℃, outmost polyethylene layer will not have polarity, also just can come hot weld to close with liquid.

This plastic substance that makes earlier melts, use flute profile mould extruded polyethylene layer and so-called blown film (polyethylene that has melted to be squeezed into tubulose via a circular die again, with compressed air its inflation is got up again, its diameter is increased greatly) polyethylene layer made of method relatively, its mechanical property has suitable difference.The difference of these manufacture methods is that in the blowing process temperature of extruding plastic is 140-180 ℃, and in corresponding groove extrusion process, the about 250-325 of temperature ℃.Then blow by pipe, produced directionality effect in the plastic substance, molecular orientation is arranged, and the various mechanical properties of material greatly increase.In principle, modulus of elasticity doubles, and as the polyethylene film of groove extruding, modulus of elasticity approximately is 100Mpa, and the blowing polyethylene film, modulus of elasticity but is about 200Mpa.Also have, and though the fracture strength of blown film be directly to or laterally all high much (the fracture strength value of blown film has approximately improved 15-30%).Another sizable advantage is that the taste that blown film is overflowed is light, and this packing to food is crucial.

The seam characteristic of blown film is good especially, especially aspect those the hot food or the food (for example drink) that need heat in packing box, known road blowing polyethylene film is caused much slighter than the polyethylene film of groove extruding to the taste-affect of product.

Therefore, this internal layer is compared with the laminated foil of the polyethylene film that contains the groove extruding that uses so far with the laminated foil of blowing polyethylene film, has sizable advantage.Packing is subject to the food of smell influence, those food that need in packing box, heat particularly, when for example selling the coffee of disposable packaging box packing or teas drink automatically, machine can be sent packaged through warmed-up food, and the benefit of this new packing box is just more outstanding.Point out that blowing polyethylene film and groove extruded polyethylene film compare, various mechanical performances all improve a lot.Make the packing box of making again behind the pipe by the laminated thin slice, positive this advantage of good utilisation.This class packing box need entirely fold when making parallelepiped container, the double-walled bead of each dihedral triangularity of packing box, and seam more inwardly folds.In the process that folds, many places point all can have " dual folding " the laminated plastics material to occur, and in other words, ductile bed can elongate and bear sizable tensile stress.These stress can make the internal layer of packing box break usually or damage; produce little seepage, the liquid in the packing box may penetrate interior ductile bed as a result, makes each layer disintegration of laminated foil; or the fiber papery that is carried layer partially absorbs, and makes its drenched and lose mechanical strength fully.Those so-called aseptic packaging boxes the insides are a kind of sterile liquids, and leakage will contaminated food products like this, makes it lose aseptic.Avoid ductile bed folding place break the damage method be to use the blowing polyethylene film make internal layer, because of it has better tensile strength and expansion characteristics than groove extrusion film, especially modulus of elasticity doubles.The high resiliency modulus means that also this internal layer can bear mechanicalness concussion better, and for example packing box falls etc.

So we we can say, will have various outstanding advantages according to the laminated foil of Fig. 1 method manufacturing, unique inconvenient place is the operating process that needs to increase in addition the blowing polyethylene film.

In order to produce this laminated foil in this manner, still make its expense similar again with the plastic layer of the groove extruding of adopting at present, just need a rational coating process as shown in Figure 2.One automatic reel 11 is arranged among Fig. 2, and the carrying layer material of rolling up can be paper stock, cardboard and foamed polystyrene.Carry material sheet 1 and walk around the guiding reel by automatic reel 11 and be rolled onto coating place, thin slice 1 is introduced into " folder mouthful " position between cylinder 14 and 13, and cylinder 13 is cooled simultaneously.Squeezer 12 is bonded on the whole width of thin slice 1 after squeezing out the sealed polyethylene plastic 2 of molten state through the flute profile mould.Polyethylene film 2 is to push down in quite high temperature (about 300 ℃), so can be bonded in above the scraps of paper 1 securely; Because plastic sheeting 2 can constitute the skin of laminated thin slice, so can be used for protection against the tide fully, this one deck can be very thin, gets final product as 5-20 gram/rice.Cooling by chilling roll 13 settles out the plastic sheeting 2 of fusing, and the thin slice of making 15 comprises the skin of carrying layer 1 and polyethylene film thereof.Then thin slice 15 being caused second coating place with the groove extruding plastic film 3 that is extruded by squeezer 10 promptly is incorporated between pressure roller and chilling roll 8 and 9.Also having one deck aluminium foil 4 and one deck by outer layer of polyethene and EAA(ethylene acrylic acid) blown film formed of internal layer also is introduced between cylinder 8 and 9.Described blown film is to push through mixing in advance, and concrete grammar as described later.The molten plastic film 3 that is squeezed out by squeezer 10 constitutes aluminium foil 4 and thin slice 15 and is not coated with lamella or adhesive layer between laminated.When laminated together, aluminium foil 4 can be bonded on the carrying layer 1 of thin slice 15 cylinder 8 and 9 effectively thin slice 15 and aluminium foil 4 and the melting polyethylene layer between them 3.Chilling roll 9 is with plastic layer 3 coolings, being discharged heat by plastic sheeting 3 when, by aluminium foil layer 4 that heated and the EAA layer that heat energy is passed to blown film 5 through the heat conduction.The seam temperature be low to moderate about 93 ℃ EAA layer be heated to softening, when this two-layer thin slice during pressing, promptly is bonded on the aluminium foil layer 4 between cylinder 8 and 9.Then, heat energy is released to chilling roll, but the temperature of the outer layer of polyethene of heated film can not significantly improve, and reason is that the polyethylene layer of blown film 5 only directly contacts with the surface of chilling roll.

As above-mentioned method, by the polyethylene film 3 of groove extruding, the blown film 5 of thin slice 15, aluminium foil 4 and mixing extruding is laminated on together in same process, and the laminated foil of making is then gone up automatic reel 17 by volume.

As mentioned above, the production of laminated foil 16 needs the extruding plastic of blowing mixing in advance film, and it is made up of a polyethylene layer and an EAA layer.Film is pressed the method manufacturing of Fig. 3, and all extrusion die 22 Colaesces are together together for two so-called squeezers 20 and 21.That send squeezer 20 to is the EAA of particle or powdery, and melted by heat in squeezer is pushed by one or more screws simultaneously, and Rong Hua plastic substance is subject to a high pressure like this.Same polyethylene is melted in squeezer 21, in extrusion die 22, bear high pressure, in extrusion die 22, two kinds of molten plastic material are introduced into separated circular passage parallel to each other, can join in annular mouth or its vicinity of mould 22 then, make these two kinds of plastic substances form seamless pipe 24, it simultaneously is the EAA layer, and another side is a polyethylene layer.With the compressed air that is supplied to extrusion die 22,, its diameter is increased greatly these pipe 24 inflations that just formed.By means of ring-type cooling device 23 cold air is blown skin and/or internal layer at pipe, make tubular being fixed up, and check its diameter.For plastic material is fixed up, by blowing into cold air, make plastic substance extend attenuation, produce certain molecular orientation and arrange, plastic substance cooling back is fixing.Be full of the pressure roller 26 that compressed-air actuated pipe 24 upwards leads to two cooperations, plastic tube is driven plain between cylinder 26.Before the EAA internal layer is stable or be cooled to the seam temperature that is lower than plastic substance and can not flatten when following, otherwise in applanation process, can get up in the inside of plastic tube in seam.Yet when pipe 24 upwards guided, pipe 24 and its EAA internal layer cooled down, and were introduced near between the contraction guide plate 25 that cooperates cylinder 26.Pipe 24 flattens back (label among the figure is 27), shifts to cutter sweep 28 by flattening cylinder, and the cutting knife here cuts the flattened tube marginal portion, forms two thin slices that separate 31 and 32, is rolled by automatic reel 30 and 29 respectively.Therefore, thin slice 31 and 32 mixes extrusion film by blowing respectively and constitutes, and the one side of film is a polyethylene, and another side is EAA.This mixes extrusion film and is used to produce laminated foil, i.e. label among Fig. 25.Also might in the range of definition of the present invention, be applied to the combination of above-mentioned material in addition.For example, the rigidity foaming plastics that can use expanded polystyrene (EPS) one class replace paper or cardboard as carrying layer.The plastic outer layer of laminated foil and blowing inner plastic are without polyethylene, and with other polyolefin, as mixing the polypropylene that pushes with EAA or Surlyn A (Surlyn), and first adhesive layer of extruding can for example can be used instead without polyethylene: combination, EAA, Surlyn A and the LDPE of low density polyethylene (LDPE) (LDPE) and LLDPE (LLDPE) or Surlyn and LDPE or independent Surlyn.The thermoplastic that constitutes second adhesive layer also is a kind of bond plastic, and wherein most important typical material is the hydroxy acid co-polymer of carboxyl acid copolymer compound or part neutralization.Wherein, EAA is the most frequently used now polymer.

Accompanying drawing 4,5 and 6 can illustrate the formation and the operational scenario of second kind of embodiment of the present invention.

As shown in Figure 6,, inject melting of synthetic resin material 103, main stor(e)y 101 and aluminium foil 102 are pressurizeed from the two sides, they are bonded together by a pair of cylinder 105 and 106 from mould 104 traditionally for main stor(e)y 101 and aluminium foil 102 are combined into an integral body.In this case, even at high temperature Huo Hua synthetic resin material contains a large amount of oxidation products, but because aluminium foil the article of resin and packing are kept apart, so do not worry having in the article that oxidation product is eluted to packing.

In view of this, the present invention has adopted such arrangement, when soon the film of melting of synthetic resin material 103 injects between main stor(e)y 101 and the aluminium foil 102, the thermoplasticity film of synthetic resin of producing separately 107 is delivered to the inner surface (surface of aluminium foil is bonded on the main stor(e)y) of aluminium foil 102, make above-mentioned main stor(e)y 101, melting of synthetic resin material 103, aluminium foil 102 and film of synthetic resin 107, be pressed in a pair of cylinder 105 and 106, thereby melting of synthetic resin is bonded in aluminium foil on the main stor(e)y, and the heat energy of melting of synthetic resin material is attached to film of synthetic resin on the inner surface of aluminium foil simultaneously.

One of benefit of laminated foil material is that paper can be used as main stor(e)y, and optionally prints on the surface of paper.In this case, the surface that will the print outer surface of main stor(e)y just can be coated with last layer synthetic resin material usually.

Embodiment shown in Figure 4, the outer surface of main stor(e)y 101 is executed the processing method of application layer and inner surface thereof, and new distinctive feature is all arranged.

Guide pulley 108 is sent main stor(e)y 101 continuously, and the first step of process is an outer surface of melting of synthetic resin 110 being annotated main stor(e)y by mould 109, by cylinder 111 and 112, they are forced together mutually, thereby form synthetic resin layer 110 at the outer surface of main stor(e)y 101.

Then, the main stor(e)y 101 of formation is delivered to following one lamination operation of thin slice inner surface.

Main stor(e)y 101 enters a pair of cylinder 105 and 106, main stor(e)y is wrapped in above the guide pulley 113 simultaneously, aluminium foil 102 is delivered on the main stor(e)y 101 and is stacked mutually, simultaneously film of synthetic resin 107 is also delivered on the aluminium foil 102, and melting of synthetic resin material 103 is infused in position between main stor(e)y 101 and the aluminium foil 102 by mould 104 simultaneously.

Polyethylene as synthetic resin material 103 is being coated in aluminium foil on the main stor(e)y under the molten state more than 300 ℃.

Therefore, when high temperature synthetic resin material is injected between aluminium foil 102 and the main stor(e)y 101, its heat can pass aluminium foil at once, pass to the outer surface of aluminium foil, the part of the film of synthetic resin 107 of packing container inner surface just, the surface temperature of film of synthetic resin 107 is increased suddenly, and continue the very short time, make the surface of film softening after, they by force feed between cylinder 105 and 106, make main stor(e)y 101, aluminium foil 102 and built up membrane 107 tightly force together, and form the sheeting of laminar structure as shown in Figure 2, and sheeting ceaselessly is wrapped on its reel like this.

What be referred to as to press from both sides mouthful cylinder is a pair of cylinder 105 and 106, and its intermediate roll 105 is made of metal, as chilling roll, and another cylinder 106 of making by rubber, as pressing roller.Because this reason, main stor(e)y 101, melting of synthetic resin material 103, aluminium foil 102, film of synthetic resin 107, pressurize very short time by two cylinders, film of synthetic resin is painted on the surface of aluminium foil at this moment, then film of synthetic resin is by cylinder 105 coolings, so do not have the chance that a large amount of oxidation products form before its temperature descends.

Compare with the conventional method of the melting of synthetic resin material being annotated sticking to the aluminium foil surface on the main stor(e)y in advance, the inventive method promptly is coated with the method for film of synthetic resin, can reduce and produce a large amount of oxidation products, reason is: the synthetic resin material is coated in the required condition of high temperature of aluminium foil surface, only needs to continue the very short time; The surface temperature of aluminium foil is lower in the conventional method, but the effective temperature that is coated with synthetic resin is also lower than the temperature of synthetic resin itself, and in contrast to this, effective temperature of the present invention is higher.

In other words, although traditional extruded layer platen press needs the temperature of highland raising synthetic resin material as far as possible, but this effect that the present invention produces is pushed working procedure of coating under the temperature conditions that is higher than the actual generating surface of film of synthetic resin, therefore believes that overlay can be firm and solid as far as possible.

The film of synthetic resin of delivering to aluminium foil surface is to blow under the lower temperature that does not produce oxidation product, and its quality can change as required, decides according to the food species of purposes and packaging.In this case, the optimum temperature that guarantees the film of synthetic resin quality is to be injected into aluminium foil and to be between the main stor(e)y of softening temperature under its temperature of being heated, and they are bonded together.

Here allow to use blown film, film outpours two or more synthetic resin materials by a mould, adopts sandwich construction.If use this material shown in Figure 2, then the best combination of synthetic resin material is: towards the one side of aluminium foil, bonding low density polyethylene (LDPE) 7 ', one side towards food, bonding high density polyethylene (HDPE) 7 "; the newly synthetic thin slice of result all has excellent properties aspect the food resembling to adhere to main stor(e)y intensity and preserve, and therefore can obtain high-quality laminated sheeting.

Though the foregoing description concentrated discussion laminated foil material, the lamination paper can be used as main stor(e)y, in actual applications can be different but main stor(e)y itself is the synthetic resin material, for example the synthetic resin material can be polyethylene sheets material or the synthetic resin of foaming (effectiveness of the present invention).

Make the method for the sheeting that sheathing foodstuff uses according to the present invention, do not worry that fully the synthetic resin material layer that is pressed together on the aluminium foil inner surface can see through film of synthetic resin by elution, reason is not use the dried laminating adhesive that uses traditionally fully.

In addition, different with traditional extruded layer platen press, can't be under the high temperature for a long time towards the synthetic resin material layer of food, so it is quite little to produce the chance of oxidation product.

Because this reason, though traditional manufacture method is subjected to the influence of oxidation product in adhesive and the synthetic resin material, taste and smell are changed, but but can minimize the influence of packing container food according to the sheeting of the inventive method manufacturing.In other words, method of the present invention can not influence the quality of food, can preserve food long-time as far as possible and keeps finely, and is very effective to packing those food that are subject to smell and taste influence simultaneously, for example various beverages etc.

The temperature of oxidation product is high more, and is also remarkable more by the variation of the taste of its caused food and smell.For this reason, heating milk and coffee that this laminated foil material of employing conventional method manufacturing is used to pack and sell on market are impossible, yet this laminated foil material packaged food that adopts the inventive method to make, even heat again when needing, but can not cause the change of the taste and the smell of food, and on market, sell also and can keep for a long time, all can obtain gratifying effect for the sale of variety of way.

In addition, according to method of the present invention, the quality of aluminium foil and built up membrane can not change, more can be bonded to each other securely than conventional method, very big retractility is arranged again, can bear fold, do not have the crack at inflection point yet, the intensity of packing box is increased, therefore, in transportation, also reduced the chance of the damage and the distortion of packing box.

Other characteristics of the inventive method are to simplify production equipment, lower production cost.Specifically, the present invention, when aluminium foil surface is coated the synthetic resin material, do not need to supply in addition the device of heat and injection, these equipment are essential in the conventional extruded laminating method, in addition, coating process does not need coating and drying equipment are installed yet, and these equipment also are essential in dried laminating; The present invention can effectively utilize the heat of the synthetic resin material of high temperature melting, is injected between aluminium foil and the main stor(e)y, and synthetic resin can be bonded on the surface of aluminium foil.

Use method of the present invention, can produce laminated foil rationally, cheaply, its characteristic is more more superior than the laminated foil of producing now, and particularly the inner face of laminated foil is made up of the polyethylene film of blowing, thereby has been replaced traditional groove extrusion film.

Claims (9)

1. But 1, wrapping have a laminated foil material that good mechanical strength and grease resistance and hot weld are closed, and it is characterized in that it comprises:
2. A) but the carrying layer of rigidity fold (1) is for example used paper, cardboard or rigidity foaming plastics,
3. B) execute the heat resistant plastice skin (2) that applies in carrying layer (1) one side,
4. C) execute polyethylene first adhesive layer (3) that applies at carrying layer (1) another side,
5. D) be bonded in aluminium foil layer (4) on polyethylene first adhesive layer,
6. E) be bonded in surperficial EAA second adhesive layer (7) of aluminium foil (4),
7. F) be combined in blowing polyethylene film internal layer (6) on second adhesive layer (7).
8. 2, according to the laminated foil material of claim 1, the modulus of elasticity and the intensity that it is characterized in that blowing the internal layer (6) of heat resistant plastic material are significantly higher than the skin (2) that groove pushes.
9. 3, make the method for the laminated foil material of claim 1 or 2, wherein, the material sheet (1) that carries of paper or cardboard is coated the outer layer of polyethene (2) of being pushed by groove in advance, then by means of extruded polyethylene adhesive layer (3), press known method lamination aluminium foil (4), above-mentioned thin slice (1) and the aluminium foil (4) of carrying brought into simultaneously and cooperated pressure roller (8,9) in, it is characterized in that the thin slice (5) that also has a mixing made from blowing method in advance to push is introduced into above-mentioned pressure roller (8,9), the mixing sheet extrusion is a polyethylene layer in the face of the one side of pressure roller (9), and its one side in the face of aluminium foil is ethylene acrylic acid (EAA) coating, the selection of the extrusion bonded layer of polyethylene (3) institute heat content should make adhesive layer (3) itself be bonded on carrying layer (1) and the aluminium foil layer (4) on the one hand, make the heat energy on the adhesive layer (3) be transmitted on the EAA coating (7) of mixing extruded layer (5) by aluminium foil layer (4) on the other hand, become the laminate with mechanical strength when whole when EAA layer (7) touches aluminium foil layer (4), its temperature rises to more than 93 ℃.

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