RU2632494C1 - Production method of multilayer material by application of extruded polymer coating at calendering - Google Patents

Abstract

FIELD: packaging industry.

SUBSTANCE: provided the production method of sheet or rolled material, having polymeric layers and non-polymeric functional or decorative layer, which contains the application of the polymer coating to the initial film, having the support polymer layer and the binded with it non-polymeric functional or decorative layer. While the coating is applied, the molten extruded polymeric material is subsequently passed through two cooling calendering gaps, forming the coating polymer layer in the first gap with the thickness greater than the thickness of the initial film, and the initial film is fed into the second or subsequent gap, providing the binding of the coating polymer layer and the initial film. In the mentioned gap provide the initial film coverage of one of the calenders with the direct contact of the initial film first side with the surface of this calender and the second side of the initial film - with the covering polymer layer.

EFFECT: reduction of the initial film deformation, in particular the decorative or functional layer, the technology simplification and productivity increase.

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Description

Technical field

The invention relates to the field of polymeric materials for the production of packaging and other products, and in particular to a method for producing a rolled or sheet multilayer material.

State of the art

Polymer-based materials that have decorative or functional layers, in particular printed layers (ink layers), metallized and barrier layers, are widely used as materials for packaging production.

However, decoration (printing, metallization, dulling, etc.) of hard polymer films with a thickness of 150 microns or more is associated with the need to use special, expensive equipment. Printing on such thick films is not economically feasible. It is possible to apply inexpensive printing methods, for example flexoprinting. However, when it is used on films of the specified thickness, rapid wear of the equipment occurs. This raises technological difficulties in ensuring print quality.

Therefore, in the production of materials with a thickness of more than 150 microns, it is advisable to apply various technologies for joining a thin polymer film (10-100 microns) having a decorative or functional layer with a thicker polymer film (150-1000 microns).

Known technologies for joining films in which films are passed through calender gaps with simultaneous heating (see, for example, RF patent RU 2152339, July 10, 2000). Known methods for co-extrusion of films and their subsequent calendering (see, for example, RF patent RU 2202473, 04.20.2003). Also known are technologies for forming laminating layers by caching or extrusion of a material onto a substrate (see, for example, RF patent RU 2329187, July 20, 2008).

The technology of extrusion lamination is widely known, in which adhesive material is extruded between two joined films (see, for example, RF patent RU 2405676, December 10, 2010).

The above technologies are not suitable for producing thick films with a decorative or functional layer, since the layers are deformed during processing, which affects their consumer and operational qualities. In particular, when the printing layer is deformed, there is a distortion of the inscriptions and drawings made on the packaging material.

The in-mold labeling technology has found wide application for the production of packaging with printing (see, for example, US patent, US 7588157, September 15, 2009). According to this technology, an initial film (label) having a printing layer is melted into a finished product (for example, a container) during its formation. The disadvantage of this technology is its complexity, as well as the need to use expensive equipment. In addition, it is not suitable for roll and sheet materials.

As the closest analogue of the considered solution for the totality of the techniques used, the method for producing a multilayer material disclosed in Japanese patent JP 2600273, 10.24.1989, can be selected. According to this method, the original corrugated sheet material with a thickness of 20 to 500 μm having a printing layer is passed between calendars. At the same time, a second film obtained by extrusion is fed onto the printing layer, calendering the packet of layers, heating it and then compressing it to obtain a multilayer material with a thickness of 1 to 10 mm. The initial film is made of acrylic resin, and the covering layer is made of polyvinyl chloride or acrylic resin. This technology also has the disadvantage of deformation of the printed layer.

Disclosure of invention

The objective of the invention is to provide a simple technology for producing multilayer sheet or rolled materials based on polymers having a decorative or functional layer for the manufacture of packaging or other products.

The technical result of the invention is to reduce the deformation of the original film, in particular a decorative or functional layer, simplifying the technology (in particular, refusing to use an adhesive layer of glue), increasing the productivity of the technology, reducing cost, expanding the ability to apply layers of various materials.

The specified technical result is achieved due to the fact that the method of producing a multilayer sheet or roll material involves applying a polymer coating to the original film having at least one supporting polymer layer and at least one non-polymer functional or decorative layer associated with it, and when applying the coating the molten extruded polymer material is sequentially passed through at least two gaps of the cooling calendars, with the formation in the first gap covering its polymer layer with a thickness greater than the thickness of the original film, and in the second or subsequent gap serves the original film to ensure the connection of the coating polymer layer and the original film, while in the specified gap provide coverage of the original film of one of the calendars with direct contact of the first side of the original film with the surface of this calender, and the second side of the original film with a coating polymer layer.

In addition, there are private options for implementing the method, according to which:

- a coating polymer layer is applied from the side of the reference polymer layer of the original film,

- the coating polymer layer is applied from the non-polymer decorative or functional layer of the original film,

- the molten extruded polymer material is passed through at least three gaps of the cooling calendars, and an additional film is fed into the third or subsequent gap of these calendars to ensure its connection with the coating polymer layer,

- use three calendars placed vertically or at an angle, with the first calendaring gap formed by the upper and middle calendars, and the second calendaring gap formed by the middle and lower calendars, and when coating is applied, they cover the initial film of the lower calender,

- before feeding the original film into the second calender gap, provide it with a clamp to the covering polymer layer by means of a clamping shaft,

- use the original film, in which the reference polymer layer is made of polyethylene or polypropylene, or polyethylene terephthalate,

- use the original film, in which the non-polymer decorative or functional layer is a printing layer and / or a barrier layer, and / or a reflective layer,

- as a coating polymer layer, a layer of polyethylene or polypropylene, or polyethylene terephthalate, or polystyrene, or polyvinyl chloride is applied,

- use an additional film made of polyethylene or polypropylene, or polyethylene terephthalate,

- use the original film in which the thickness of the support layer is 10-100 μm,

- use the original film in which the thickness of the non-polymer functional or decorative layer is 1-50 microns,

- covering polymer layer is applied with a thickness of 150-1000 microns,

- when coating the temperature of the calendars (4, 5, 6) is 25-130 ° C,

- when coating the molten extruded polymer material has a temperature of 200-300 ° C, and the coating polymer layer when fed into the second calender gap has a temperature of 150-230 ° C.

In contrast to the known technologies, in the claimed method, the coating (lamination) of the film with a non-polymer decorative or functional layer in the calendars is carried out in such a way that it covers one of the calendars in contact with most of its surface, and a plastic coating layer formed of extruded polymer material , served on the other side of the original film, not in contact with the calender. Due to the calender cooling of the film in contact with it, the latter, upon contact with heated polymer material, does not heat up to the melting point or an unstable physical and mechanical state. Thus, this technique allows to reduce the deformation of the original film and preserve the geometry of the non-polymer functional or decorative layer.

Brief Description of the Drawings

The invention is illustrated by drawings, where:

- in FIG. 1 shows examples of the configuration of the original film,

- in FIG. 2 shows examples of the configuration of the obtained multilayer material,

- in FIG. 3 shows a line for implementing the claimed method.

The implementation of the invention

The initial film (1) for coating (lamination) (Fig. 1) is a roll or sheet material and contains at least one polymer support layer (2) and at least one non-polymer functional or decorative layer connected to it (3) . As the material of the support layer, in particular, polyethylene, polypropylene, polyethylene terephthalate, etc. can be used. As a decorative non-polymer layer (3), a printing layer (ink layer) can be used. As a functional non-polymer layer (3), a barrier and metallized layer can be used.

The initial film may have a supporting polymer layer (2) and a non-polymer layer (3) or two supporting polymer layers (2), between which there is a non-polymer functional or layer, deposited on one of its sides (see Fig. 1, a, 1, b) decorative layer (3).

The starting film (1) may include either one or several support layers connected by coextrusion with the addition of barrier layers within each layer. Variants of combining in the original film the functional and decorative layers located on separate supporting layers connected by an adhesive layer are possible. The thickness of each of the layers (2) and (3) is preferably from 1 to 50 microns.

The original film can be obtained by standard technology, which involves applying a decorative or functional layer to a polymer substrate (backing layer). In particular, flexo, rotogravure or offset printing, as well as other types of printing, can be used.

The line for implementing the inventive method (Fig. 3) includes at least three rotating calenders (4, 5, 6) (shafts), forming two or more gaps for sequentially passing the extruded material. The indicated calendars (4, 5, 6) can be arranged vertically one above the other, either horizontally or at an angle.

The line design includes a flat-slot extruder (7) with a die (8) for feeding the molten extruded material (9) into the first calender gap. In the case of three calendars arranged vertically (as shown in FIG. 3), the molten extruded material (9) is fed in such a way that the first gap is formed by the upper (4) and middle (5) calendars, and the second gap by the middle (5) and lower calendars (6).

The original film (1) can be fed into the second gap of the calendars (5) and (6), or in any of the subsequent gaps (third, fourth, etc.), if any. When using tape (roll material) as the initial film (1), it is fed through an unwinding unit (10), and the resulting multilayer material (11) enters the rewinder (12). To obtain individual sheets of material, instead of the winder, a knife for cutting the blade and a table for stacking sheets are installed.

In a particular embodiment of the invention, the line may further comprise a clamping shaft (13) for pressing the initial film to the material covering it before the second gap. Also, additional unwinding units may be provided in the line for supplying additional films to the third or subsequent calender clearances (not shown).

When implementing the inventive method, the extruded molten polymer material, with a temperature of about 200-300 ° C, is fed from above into the first (upper) gap between the upper (4) and middle (5) calendars, in which it is molded and partially cooled to form a plastic polymer coating layer (14) in the form of a web. Next, the covering layer (14) goes around the middle calender (6) and falls into the second gap formed by calendars (5) and (6). By means of the drum (10), the initial film (1) is fed into the specified second gap, so that it essentially covers the lower calender (6) in the specified gap and on one side directly contacts the surface of this calender (6). In this case, the coating layer (14) heated to a temperature of about 150-230 ° C is in contact with the other side of the specified film (1) (in particular, passes above it).

Thus, in the second calender gap, the polymer coating layer (14) is joined to the film surface (1) and smoothed out. In this case, due to the contact of the initial film (1) with the lower calender, which ensures its cooling, it does not overheat due to the coating layer (14), which prevents deformation of the film (1), in particular its functional or decorative layer (3). The temperature of the calendars is, as a rule, from 25 to 130 ° C and depends on the material of the starting film and the extrudable material.

To improve the adhesion of materials before feeding into the second gap, the original film (1) can additionally be pressed to the covering polymer layer (14) by means of a clamping shaft (13). In particular, the layer (14) and the film (1) can be clamped between said shaft (13) and the middle calender (5).

After passing through the second calender gap, the resulting material can be fed into one or more calender clearances for additional smoothing (not shown in the drawings). It is also possible that an additional film can be fed into the third or subsequent calender gap, which is connected by a coating polymer layer (14).

The finished multilayer material (11) is wound into a roll by means of a winder (12) or cut into sheets and stacked on a table.

As the materials of the coating layer (14), any polymer material having adhesion to the material of the starting film (1) can be used, in particular polypropylene (PP), polyethylene terephthalate (PET), polyethylene (PE), polystyrene (PS), polyvinyl chloride (PVC) ) and others. The thickness of the coating layer (14) is preferably from 150 to 1000 microns.

It should be noted that the coating layer (14) can be applied both to the surface of the support layer (2) of the original film (1) and to the surface of the non-polymer or functional layer (3) (see Fig. 2). In both cases, the geometry of the layer (3) will be preserved.

In addition, the claimed method can be applied several coating layers. You can also use a line with more calendars to increase the smoothness of the resulting multilayer material (11).

Example 1

According to the claimed method, a rolled laminate having the configuration shown in FIG. 2c, and containing sequentially placed layers:

1. The supporting layer (2) of high pressure polyethylene (LDPE) with a thickness of 40 microns.

2. The non-polymer decorative layer (3) in the form of a print (ink) layer is about 10 microns thick.

3. The support layer (2) of biaxially oriented polypropylene (BOPP) with a thickness of 25 μm.

4. The covering layer (14) of polypropylene with a thickness of 200 μm.

The material was characterized by good adhesion of the layers and the absence of deformation of the decorative printed layer (3).

Example 2

According to the claimed method, a sheet laminate having the configuration shown in FIG. 2, b, and containing sequentially placed layers:

1. The supporting layer (2) of high pressure polyethylene (LDPE) with a thickness of 40 microns.

2. Non-polymer functional layer (3) in the form of a metallization layer with a thickness of about 1 μm.

3. The covering layer (14) of polyethylene with a thickness of 300 μm.

The material was characterized by good adhesion of the layers and the absence of defects in the metallization layer (3).

It should be noted that the invention is not limited to the embodiments described in the description. Other modifications of the proposed method are also possible within the framework of the given set of essential features. In particular, it is possible to obtain other combinations of material layers and their application modes.

Claims (18)

1. A method of obtaining a multilayer sheet or roll material (11) having polymer layers and at least one non-polymer functional or decorative layer, comprising applying a polymer coating to the starting film (1) having at least one supporting polymer layer (2) and at least one non-polymer functional or decorative layer associated with it (3), moreover, when applying the coating, the molten extruded polymer material (9) is successively passed through at least two gaps of the cooling calendars, with the formation of a coating polymer layer (14) with a thickness greater than the thickness of the initial film in the first gap, and the initial gap is fed into the second or subsequent gap a film (1) with the connection of the coating polymer layer (14) and the original film (2), at the same time, in the specified gap, one of the calendars (6) is covered by the initial film (1) with direct contact of the first side of the initial film (1) with the surface of this calender (6), and the second side of the initial film (1) with a covering polymer layer ( fourteen). 2. The method according to p. 1, in which the coating polymer layer (14) is applied from the side of the supporting polymer layer (2) of the original film (1). 3. The method according to p. 1, in which the coating polymer layer (14) is applied from the non-polymer decorative or functional layer (3) of the original film (1). 4. The method according to p. 1, in which the molten extruded polymer material (9) is passed through at least three gaps of the cooling calendars, and an additional film is fed into the third or subsequent gap of these calendars to ensure its connection with the coating polymer layer (14). 5. The method according to claim 1, in which three calendars (4, 5, 6) are used, placed vertically or at an angle, the first calendaring gap is formed by the upper (4) and middle (5) calendars, and the second calendaring gap is the middle (5) and lower (6) calendars, moreover, when coating is applied, they provide coverage of the initial film (1) of the lower calender (6). 6. The method according to p. 1, in which, before feeding the original film (1) into the second calender gap, it is pressed against the coating polymer layer (14) by means of a clamping shaft (13). 7. The method according to any one of paragraphs. 1-6, in which the original film (1) is used, in which the supporting polymer layer (2) is made of polyethylene, or polypropylene, or polyethylene terephthalate. 8. The method according to any one of paragraphs. 1-6, in which a starting film (1) is used, in which the non-polymer decorative or functional layer (3) is a printing layer and / or a barrier layer and / or a reflective layer. 9. The method according to any one of paragraphs. 1-6, in which, as a coating polymer layer (14), a layer of polyethylene, or polypropylene, or polyethylene terephthalate, or polystyrene, or polyvinyl chloride is applied. 10. The method according to p. 4, which use an additional film made of polyethylene, or polypropylene, or polyethylene terephthalate 11. The method according to any one of paragraphs. 1-6, in which the original film (1) is used, in which the thickness of the support layer (2) is 10-100 μm. 12. The method according to any one of paragraphs. 1-6, in which the original film (1) is used, in which the thickness of the non-polymer functional or decorative layer (3) is 1-50 microns. 13. The method according to any one of paragraphs. 1-6, in which the coating polymer layer (14) is applied with a thickness of 150-1000 microns. 14. The method according to any one of paragraphs. 1-6, in which when applying the coating, the temperature of the calendars (4, 5, 6) is 25-130 ° C 15. The method according to any one of paragraphs. 1-6, in which when coating the molten extruded polymer material (9) has a temperature of 200-300 ° C, and the coating polymer layer (14) when fed into the second calender gap has a temperature of 150-230 ° C.

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