KR200286909Y1 - Laminate tube having plastic multi-layer sheet structure - Google Patents

Abstract

The present invention relates to a plastic multilayer sheet structure formed by laminating a plurality of thermoplastic synthetic resins having different physical properties by a coextrusion method, and more specifically, a surface layer and a tube composed of a tube inner surface layer forming an inner surface of a tube and an outer surface layer forming an outer surface of a tube. A laminate tube consisting of a gas barrier layer for preventing gas permeation into a layer, and an adhesive layer for adhering the surface layer and the gas barrier layer, wherein the gas barrier layer is a polyolefin and its derivatives, polyvinylidene chloride, ethylene vinyl alcohol copolymer and A laminate tube particularly suitable for toothpaste tubes, characterized in that it is made of a plastic material selected from the group consisting of nylon MXD6. In the laminated tube of the plastic multi-layer sheet of the present invention, a plastic material having excellent gas barrier properties and aroma barrier properties, and a gas and aroma barrier and oxygen absorption function at the same time, instead of the aluminum sheet used in conventional tubes as a gas barrier layer. By using materials or plastic material with excellent moisture barrier properties, gas and fragrance barrier properties and moisture barrier properties can be maintained at a similar level as that of conventional laminate tubes, while having excellent resilience that conventional tubes do not have. It is convenient to use and eliminates the rigidity due to the thin aluminum sheet to provide a high quality, environmentally friendly laminate tube that is soft to the touch.

Description

Laminate tube of plastic multilayer sheet structure {LAMINATE TUBE HAVING PLASTIC MULTI-LAYER SHEET STRUCTURE}

The present invention relates to a laminate tube of a multi-layer sheet structure composed only of a plastic material. More specifically, the present invention is a group consisting of polyolefins and derivatives thereof, polyvinylidene chloride, ethylene vinyl alcohol copolymers and nylon MXD6 (Meta Xylene Diamine) without using aluminum foil as a gas barrier layer, unlike conventional laminate tubes. Plastic material selected from among them, more preferably ethylene vinyl alcohol (EVOH) copolymer or nylon MXD6, ethylene vinyl alcohol or nylon MXD6 with oxygen absorbent, or other polyolefin material, and such a gas barrier layer, Provided is a laminate tube manufactured by laminating a polyolefin-based film or an aluminum vapor-deposited PET film on a coextruded multilayer sheet, or coextruded each layer using only a plastic material as a surface layer, an adhesive layer, or the like. The laminate tube according to the present invention has gas and fragrance barrier properties and water barrier properties similar to those of conventional tubes, and has excellent resilience that conventional tubes do not have. The present invention relates to an environmentally friendly laminate tube having a plastic multilayer sheet structure.

Early tubes have been used for a long time as a single layer of metal foil made of thick iron or the like. However, these metal tubes have a number of disadvantages such as high price compared to other tubes, easy recesses, little restoring force, difficult bending and damage to proper bending. Recently, a laminate tube having a certain restoring force is generally used by using a thin aluminum layer as a barrier layer and stacking a plurality of polymer layers as a tube to compensate for these disadvantages.

As an example, Korean Patent No. 1991-0008844 discloses a multilayer flexible sheet structure in the form of a flexible tube commonly used for filling paste-type products, and the use of these sheet structures. According to this patent, a thin aluminum sheet layer is used as the barrier layer, and in addition, a plurality of polymer layers are bonded to provide a multilayer sheet structure having improved chemical resistance and enhanced strength and bending stability.

The structure of the laminate tube used in this way is mainly composed of an ethylene acrylic acid copolymer (EAA) having high adhesion to the inner layer (13) and the outer layer (11) using an aluminum sheet as shown in FIG. After coating with the back and the like, the outermost 10 and the inner 14 are generally bonded to each other with a polyethylene film, and in some cases, a copolymer layer mixed with a pigment may be added.

In more detail, the aluminum thin plate was used as a blocking layer to suppress gas permeation and moisture permeation, and to bond polyethylene films to inner and outer layers to add chemical resistance, as well as to compensate to a certain extent that metals do not have resilience.

However, until now, laminated tubes use aluminum foil as a barrier layer, which is excellent in gas and moisture barrier properties, but is not easy to dent due to reduced restoring force due to aluminum metal, and is bent when the tube is bent. The parts may be cut or broken, and the contents may leak, the rigidity of the metal may be stiff, and the environmental pollution may be caused.

Therefore, the present inventors conducted an intensive study to find a new material that can avoid the above-mentioned disadvantages while utilizing the advantages of the existing aluminum sheet. As a result, the aluminum tube is replaced with a plastic material having excellent gas and fragrance barrier, or a plastic material having a function of oxygen absorption and a plastic barrier having excellent moisture barrier property, thereby making the existing tube have the greatest advantage. After confirming that one problem can be solved, the present invention was completed.

Therefore, the object of the present invention is to construct a laminated tube of a multi-layer sheet structure, by replacing the aluminum thin plate with a plastic material which has excellent gas and fragrance barrier properties and also has the function of oxygen absorption at the same time, gas and fragrance barrier properties and water barrier properties A plastic that can maintain the similarity of laminate tube and has excellent resilience that conventional laminate tube does not have, making it convenient for consumers to use, providing bending stability, and eliminating the rigidity of the tube to have a soft touch. An environmentally friendly laminate tube having a multilayer sheet structure is provided.

1 is a cross-sectional view of a conventional laminate tube.

2 is a cross-sectional view of one embodiment of a laminate tube according to the present invention.

3 is a cross-sectional view of another embodiment of a laminate tube according to the present invention.

<Explanation of symbols for the main parts of the drawings>

<Figure 1>

10: tube outer surface layer 11: adhesive layer

12: gas and odor barrier layer 13: adhesive layer

14: inner surface layer of the tube

<FIG. 2>

15: Tube outer outer surface layer 16: Tube inner outer surface layer

17: adhesive layer 18: gas and odor barrier layer or functional barrier layer

19: adhesive layer 20: inner surface layer inside the tube

21: tube outer inner surface layer

3

22: moisture barrier layer 23: coating layer

24: tube outer outer surface layer 25: tube inner outer surface layer

26: adhesive layer 27: gas and odor barrier layer or functional barrier layer

28: adhesive layer 29: inner surface layer inside the tube

30: tube outer inner surface layer

In order to achieve the above object, the laminate tube of the present invention melts a plurality of thermoplastic synthetic resins having different physical properties from different extruders, and each resin flows out in a feed block to form a desired layer structure. It consists of a multi-layered sheet (sheet) structure manufactured by the co-extrusion method to form a plate through. For example, the laminate tube of the present invention blocks the gas inner and outer fragrances of the tube inner surface layers 20 and 21 forming the inner surface of the tube and the tube outer surface layers 15 and 16 forming the outer surface, as shown in FIG. And a barrier layer 18 added up to the function of oxygen absorption, and adhesive layers 17 and 19 for adhering each layer. The tube inner surface layer is again composed of an outer inner surface layer 21 and an inner inner surface layer 20, and the outer surface layer is again composed of an outer outer surface layer 15 and an inner outer surface layer 16.

As the material of the inner and outer surface layers of the tube, polyolefin-based resins such as polyethylene and polypropylene having excellent chemical resistance and moisture barrier properties may be used, and among them, particularly, the thermal adhesiveness is excellent, the restoring power is excellent, and the soft touch Preference is given to polyethylene having. More particularly, it is preferable to use low density polyethylene (LDPE), linear low density polyethylene (LLDPE) or copolymers thereof, which have excellent heat adhesion and chemical resistance, and linear low density polyethylene having a bending strength of 110 kg / cm 2 or less. Most preferred. This requires a sealing strength to prevent the adhesive site from bursting due to any impact after thermal bonding, and to prevent the deterioration of the contents by blocking moisture from the outside. Especially in the case of the inner surface layer of the tube, the gas barrier layer is damaged by inhibiting chemical activity of the contents. This is because you have to use a material that doesn't work. In addition, the thickness of the inner and outer surface layers is preferably about 40-150 μm, which may have appropriate sealing strength and restoring force.

In addition, the tube inner surface layer should not be added any other chemical components other than the polyolefin resin used as the surface layer material for the stability and hygiene of the contents. For example, antioxidants, UV stabilizers, slips, antistatics, or master batches (colors processed by dispersing salts and pigments in high concentrations in resins) to add color to the tubes, for example. Synthetic resin additives such as pigments are preferably added to the outer surface layer of the tube. The content of the master batch is preferably at least 8-25 wt% of the total weight of the sheet, because when the content of the master batch is less than 5 wt%, the concealment is reduced and the toothpaste contents are reflected out.

As the adhesive layer of the tube, a polyolefin-based material such as polypropylene or polyolefin may be used, but an admer that provides adhesion with a gas barrier layer using a linear low density polyethylene used as a surface layer as a base resin is preferable. Do.

As such, the adhesive strength of the adhesive layer that bonds the surface layer and the gas barrier layer should be unpeelable. As used herein, the term "non-peelable" means that substantially no exfoliation is caused by external stress applied to the tube during use of the tube, including bending, folding, and the like.

Characterized in the laminate tube of the present invention, the barrier layer for blocking the gas permeated from the outside of the tube is polyolefin or derivatives thereof, polyvinylidene chloride (PVDC), ethylene vinyl alcohol (EVOH) copolymer, nylon MXD6, etc. Can be used. The gas permeability of these gas barrier layers is preferably 10 μs / 20 μm · m 2 · atm · 24 hr or less because it prevents deterioration of the contents and enhances long-term storage. In addition, it is particularly preferable that the gas barrier layer has a gas permeability of 1 Pa / 20 μm · m 2 · atm · 24 hr or less under 35 ° C. and dry conditions.

In addition, the gas barrier layer in the laminate tube of the present invention may be applied as a functional barrier layer having not only a gas barrier function but also a function of oxygen absorption. The gas permeated from the outside of the tube may be blocked to some extent through the barrier layer, but there is some gas which is not blocked and permeated. Over time, the performance of the barrier layer decreases little by little, and the amount of gas permeated gradually increases, especially oxygen permeability. Increasing decreases the retention of the contents. In addition, ethylene vinyl alcohol shows a great vulnerability to moisture, and when a lot of moisture is present, its barrier property tends to be greatly reduced.

Therefore, the present inventors include a functional barrier layer having both a gas barrier function and an oxygen absorption function to absorb oxygen remaining in the tube and the contents as well as the gas permeated from the outside, thereby minimizing the damage caused by oxygen, thereby reducing the preservation of the contents. Greatly improved. As the functional barrier layer, a thermoplastic resin containing an oxygen absorbent such as an iron-based composition, a polyhydric phenol compound, an organometallic compound, or a food additive system can be used. The oxygen permeability of the functional barrier layer is preferably 0.05 Pa / 20 μm · m 2 · atm · 24hr or less at 35 ° C. and 85% RH.

Although the thickness of this functional barrier layer will vary depending on the amount of oxygen absorption required, it is preferable to set it to at least 10-30 µm or more, because if the thickness of the oxygen absorption layer is less than 8 µm, it is difficult to maintain the oxygen absorption performance for a long time. Because there is. In addition, the content of the oxygen absorbent contained in this layer is preferably about 10-50 wt% because the oxygen absorption performance may be lowered when the content of the oxygen absorbent is less than the above range.

As another embodiment of the laminate tube according to the present invention, the moisture barrier layer 22 may be laminated by the extrusion lamination method in the multilayer sheet structure of FIG. 2 as shown in FIG. 3 for complete moisture barrier. As the moisture barrier layer, polyolefin polymer, aluminum vapor-deposited PET, or a composite thereof may be used. The water barrier layer preferably has a water permeability of 10 g / 30 μm · m 2 · atm · 24 hr or less, more preferably 0.5 g / 30 μm · m 2 · atm · 24 hr.

The laminated tube according to the present invention configured as described above may be used as a tube for packaging various paste-like materials, and in particular, for packaging toothpaste, ointment, and the like.

The present invention is described in more detail by the following examples, but the present invention is not limited in any way by these examples.

Example 1

A plastic multilayer sheet having a seven-layered layer structure having the thickness and material as described below was manufactured by coextrusion using five extruders.

(Inside) A: B: C: D: E: F: G (outside) = 66: 76: 17: 22: 17: 76: 66

A: tube outer inner surface layer

Material: linear low density polyethylene

Melt index: 2.7g / 10min

Flexural Strength: 110 kg / ㎠

Heat Deflection Temperature: 107 ℃

Moisture permeability: 2 g / 30 μm · m 2 · atm · 24hr

B: inner surface layer inside the tube

Material: linear low density polyethylene (85 wt%)

Melt index: 2.7g / 10min

Flexural Strength: 110 kg / ㎠

Heat Deflection Temperature: 107 ℃

Moisture permeability: 2 g / 30 μm · m 2 · atm · 24hr

Antimicrobial and Masterbatch White (15 wt%)

C, E: adhesive layer

Material: linear low density polyethylene

Adhesive Strength: Non-peelable (not torn)

D: gas barrier layer

Material: Ethylene Vinyl Alcohol (EVOH)

Oxygen permeability: 0.5 kPa / 20 μm · m 2 · atm · 24hr (35 ° C., dry)

E: tube inner outer surface layer

Material: linear low density polyethylene (85 wt%)

Melt index: 2.7g / 10min

Flexural Strength: 110 kg / ㎠

Heat Deflection Temperature: 107 ℃

Moisture permeability: 2 g / 30 μm · m 2 · atm · 24hr

Antimicrobial and Masterbatch White (15 wt%)

G: tube outer outer surface layer

Material: linear low density polyethylene (85 wt%)

Melt index: 2.7g / 10min

Flexural Strength: 110 kg / ㎠

Heat Deflection Temperature: 107 ℃

Moisture permeability: 2 g / 30 μm · m 2 · atm · 24hr

Antimicrobial and Masterbatch White (15 wt%)

Example 2

Except for adding a functional barrier layer having the function of gas barrier and oxygen absorption at the same time instead of the gas barrier layer was prepared as in Example 1 using the same process and material.

(Inside) A: B: C: S: E: F: G (outside) = 66: 76: 17: 22: 17: 76: 66

S: functional barrier layer

Material: Ethylene Vinyl Alcohol (EVOH) + Ascorbic Acid (Oxygen Absorber)

Moisture permeability: 0.5 kPa / 20 µm · m2 · atm · 24hr (35 ° C, 85% RH) or less

Example 3

Using the same process and material as in Example 1 to prepare a multi-layered sheet having a seven-layer layer structure and then laminated the moisture barrier layer on the outer surface by an extrusion lamination method.

(Inside) A: B: C: D: E: F: G: H: I (outside) = 66: 76: 17: 22: 17: 76: 66: 15: 52

H: coating layer

Material: Polyethylene

I: moisture barrier

Material: Aluminum Evaporated PET / Linear Low Density Polyethylene (LLDPE)

Moisture permeability: 0.5 g / 30 μm · m 2 · atm · 24hr or less

According to the laminated tube of the plastic multi-layer sheet of the present invention, instead of using an aluminum sheet as the gas barrier layer, a plastic material having excellent gas barrier properties and aroma barrier properties or a plastic material having moisture and gas barrier properties and oxygen absorption at the same time Gas and fragrance barrier and moisture barrier are maintained at the same level as that of conventional laminate tube, while having excellent resilience that conventional tube does not have, and it is convenient for consumers to use. It is possible to manufacture a high quality environmentally friendly laminate tube having a soft touch by eliminating the rigidity due to the aluminum sheet.

Claims (5)

A laminate tube comprising a surface layer consisting of a tube inner surface layer forming an inner surface of a tube and a tube outer surface layer forming an outer surface, a gas barrier layer for preventing gas permeation into the tube, and an adhesive layer for adhering the surface layer and the gas barrier layer, Laminate tube, characterized in that the gas barrier layer is made of a plastic material selected from the group consisting of polyolefins and derivatives thereof, polyvinylidene chloride, ethylene vinyl alcohol copolymers and nylon MXD6. The gas barrier layer of claim 1, wherein the gas barrier layer further contains an oxygen absorbent selected from the group consisting of iron-based compositions, polyhydric phenol compounds, organometallic compounds, and food additives to prevent gas permeation into the tube as well as to permeate or to Laminate tube, characterized in that it further has the ability to absorb the remaining oxygen. The laminate tube according to claim 1, wherein the inner and outer surface layers of the tube are made of polyolefin resin such as polypropylene, low density polyethylene (LDPE), linear low density polyethylene (LLDPE), or a copolymer thereof. The laminate tube according to claim 1, wherein a moisture barrier layer is further laminated on the outer surface layer of the tube by an extrusion lamination method. 5. The laminate tube of claim 4, wherein the moisture barrier layer is selected from the group consisting of polyolefin polymers, aluminum deposited PET, or composites thereof.