Double easy-to-tear opening structure of multi-layer composite packaging tin for fresh dough products

Abstract

The utility model relates to a double easy-to-tear opening structure of a multi-layer composite packaging tin for fresh dough products. The multi-layer composite packaging tin is provided with an inner composite sealing layer, a middle reinforcing layer, an outer opening layer and an outer sleeve label layer from inside to outside, the inner layer, the middle layer and the outer layer are spirally rolled, bonded and cut into a multi-layer composite cylindrical pipe in a staggered mode in the same direction, end covers are sealed at the two ends of the multi-layer composite cylindrical pipe, the outer sleeve label layer is sleeved on the two ends of the multi-layer composite cylindrical pipe, and the multi-layer composite packaging tin for the fresh dough products is formed. The inner composite sealing layer is spirally overlapped, the middle reinforcing layer is spirally butted, and the outer opening layer is also of a spirally overlapped rolled structure. An inclined sharp corner easy-to-tear opening for opening the outer opening layer is formed in the spiral overlapping convex part of the outer opening layer and close to the sealing end cover in the circumferential direction; the surface of the outer sleeve label layer is respectively provided with a row of through holes along the two sides of the whole palm sealing seam, so that the through hole perforation easy-to-tear strip for opening the outer sleeve label layer is formed. The utility model is the improvement and update of the prior art, and has the advantages of simple and feasible process, lower processing cost, more convenience for consumers to open, and the like.

Description

Technical Field

[0001] The utility model belongs to the category of packaging containers, and particularly applies to the opening structure of a multi-layer composite packaging can for "fresh fermented dough" products. Specifically, "oblique sharp-angle easy-to-tear openings" and "perforated and butt-jointed easy-to-tear strips" are respectively arranged on the outer opening layer and the outer jacket label layer of the packaging can. Background Art

[0002] The prior art relatively close to the utility model is a Chinese patent previously applied for by the inventor himself, namely, "a spiral pop-top can packaging structure of a composite material", with the patent number: ZL201720992995.3, the authorization announcement date: August 10, 2018, and the authorization announcement number: CN207712469U. However, during the pilot test of the fresh fermented dough product, the inventor of the prior art found that there are some defects in the above prior art that need to be improved and updated. For example: 1) In the prior art, the inner, middle, and outer layers of the packaging can body are all spirally wound in a butt-jointed form. However, if the outer opening layer is also spirally wound in a butt-jointed form, it is not only difficult to form an opening during production, but also difficult for consumers to tear such an opening, and such an opening does not have an easy-to-tear opening effect; 2) In the prior art, a longitudinal tear strip is integrated on a heat-shrinkable sleeve. However, since the material strength of the tear strip is much lower than that of the heat-shrinkable sleeve, two problems will occur: one is that the tear strip itself is broken when the heat-shrinkable sleeve is opened, which will cause difficulties for consumers to open; the other is that the tear strip is likely not to be neatly torn along the expected position on the outer jacket label layer during opening, which will result in consumers being unable to normally read the printed graphic and text content on the outer jacket label layer.

[0003] All the above practical problems revealed during the pilot test of the fresh fermented dough product await the inventor of the prior art to further improve and update the easy-to-tear opening structure of the multi-layer composite packaging can for this product. Summary of the Invention

[0004] The purpose of the utility model is to make improvements and updates in view of the defects such as difficult production and inconvenient opening of the multi-layer composite packaging can in the prior art, and to provide a double-easy-to-tear opening structure for the multi-layer composite packaging can of the fresh fermented dough product. The double-easy-to-tear opening structure of the multi-layer composite packaging can is more reasonable, easy to implement in production, and has a lower cost. When consumers open the multi-layer composite packaging can, it is not only more convenient, but also does not damage the readability of the printed graphic and text content on the outer jacket label layer.

[0005] The double-easy-tear opening structure of a multi-layer composite packaging can for a fresh fermented dough product according to the present utility model. The multi-layer composite packaging can includes, from the inside to the outside: an inner composite sealing layer, a middle reinforcing layer, an outer opening layer, and an outer sleeve label layer. The inner, middle, and outer layers are mutually offset. After being spirally wound, bonded, and slit in the same direction with offset, a multi-layer composite cylindrical tube is formed. Sealing end caps are provided at both ends of the multi-layer composite cylindrical tube, and a tubular outer sleeve label layer is heat-shrunk thereon to jointly form the multi-layer composite packaging can for the fresh fermented dough product.

[0006] The inner composite sealing layer of the main structure of the multi-layer composite packaging can is formed by spirally laminating and winding 4 - 6 layers of plastic film, aluminum foil (or aluminized), and kraft paper. The overlapping parts of the lamination are bonded by heat melting or sizing; the middle reinforcing layer is formed by spirally winding a single layer of high-grammage kraft card with butt joint; the outer opening layer is formed by spirally laminating and winding a single layer of low-grammage kraft paper or coated paper, and the overlapping parts of the lamination are bonded by sizing; on the spirally laminated convex part of the outer opening layer, an opening mechanism of an "oblique sharp-angle easy tear" is provided along the circumferential direction on one side close to the sealing end cap; on the surface of the outer sleeve label layer, graphic and text content related to the fresh fermented dough product is printed to serve as a product packaging label. To enable consumers to easily and neatly tear the outer sleeve label layer without affecting the readability of the printed graphic and text content on the outer sleeve label layer, a row of perforations is respectively provided on both sides of the entire clasp seam of the outer sleeve label, forming an opening mechanism of a "perforated stitch easy tear strip".

[0007] The double-easy-tear opening structure of a multi-layer composite packaging can for a fresh fermented dough product according to the present utility model has the following effects compared with the prior art after improvement and update:

[0008] 1. The technology described in the present utility model improves and updates the opening structure of the prior art. It not only maintains good characteristics such as good sealing performance, effective prevention of bacterial or microbial penetration, and strong antioxidant ability, but also is more convenient for consumers to open the packaging.

[0009] 2. The technology of the present utility model abandons the method of integrating a longitudinal tear strip on the heat shrinkable sleeve in the prior art. This method has two problems: one is that the tear strip itself will be broken, causing difficulties for consumers to open; the other is that the tear strip will damage the readability of the printed graphic content on the outer label layer for consumers. The technology of the present utility model adopts an opening mechanism of arranging two rows of perforated and butt-jointed easy tear strips on the outer label layer, and the positions of the two rows of perforated and butt-jointed easy tear strips are respectively on both sides of the palm joint seam of the outer label layer. Due to the existence of the perforated and butt-jointed easy tear strips, combined with the characteristic that the tensile strength of the double-layer material at the palm joint seam is doubled, when consumers open the outer label layer, they can very easily tear the outer label layer in the expected direction and position. Not only is the easy tear effect good, but the perforated and butt-jointed easy tear strips themselves will not be broken, and at the same time, the printed graphic content on the outer label layer can be completely retained for consumers to read and view;

[0010] 3. The technology of the present utility model abandons the butt-jointed spiral rolling method adopted by the outer opening layer of the multi-layer composite packaging can in the prior art. This method has two problems: one is that it is extremely difficult to achieve automation and precise positioning for pre-cutting the easy tear opening on the outer opening layer; the other is that it is also extremely difficult for consumers to open the easy tear opening prefabricated on the outer opening layer by the butt-jointed spiral rolling method. In the technology of the present utility model, the outer opening layer adopts the method of overlapping spiral rolling, which can not only very easily achieve an opening mechanism of precisely positioning and cutting an inclined sharp-angle easy tear opening at the convex part of the spiral overlap; at the same time, it also overcomes the problem that the easy tear opening of the outer opening layer in the prior art is not easy to open.

[0011] Therefore, after improvement and update, the present utility model has the advantages of simple and feasible manufacturing process, low production and processing cost, and more convenient opening of the packaging can for consumers. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] FIG Figure 1 : Schematic diagram of the double easy tear opening structure of the multi-layer composite packaging can for a fresh dough product described in the present utility model;

[0013] FIG Figure 2a : Schematic diagram of the spiral butt-jointed structure of the middle reinforcing layer of the multi-layer composite packaging can;

[0014] FIG Figure 2b : Schematic diagram of the spiral overlapping structure of the inner composite sealing layer and the outer opening layer of the multi-layer composite packaging can;

[0015] FIG Figure 3 : Enlarged schematic diagram of the palm joint seam and the perforated and butt-jointed easy tear strips on the outer label layer.

[0016] In the attached drawings: 1. Inner composite sealing layer; 2. Middle reinforcing layer; 3. Outer opening layer; 4. Outer sleeve label layer; 5. Sealing end cap; 6. Kraft paper edge on the face of the outer opening layer; 6'. Kraft paper edge at the bottom of the outer opening layer; 7. Oblique sharp-cornered tear notch; 8. Clasp seam; 9. Perforated stitch tear strip; 10. Opening of the perforated stitch tear strip. Detailed implementation mode

[0017] The following further describes the double-easy-tear opening structure of the multi-layer composite packaging can for fresh dough products according to the present utility model in conjunction with the attached drawings and embodiments.

[0018] Attached Figure 1 is a schematic diagram of the double-easy-tear opening structure of a multi-layer composite packaging can for a fresh dough product according to the present utility model. It is composed of an inner composite sealing layer 1, a middle reinforcing layer 2, an outer opening layer 3, and a tubular outer sleeve label layer 4 to form a multi-layer composite cylindrical tube, and a sealing end cap 5. In this embodiment, the inner composite sealing layer 1, the middle reinforcing layer 2, and the outer opening layer 3 are wound in a spiral manner with the same direction, and the splicing seams need to be staggered pairwise during the winding process; in this embodiment, the inner composite sealing layer 1 is spirally laminated and wound by 4 - 6 layers of plastic-aluminum composite paper (100 - 130 grams per square meter) (as Figure 2b shown), and heat fusion or sizing fusion is performed at the laminated part to achieve the sealing effect; in this embodiment, the middle reinforcing layer 2 is spirally butt-wound by high-gram-weight kraft card (350 - 450 grams per square meter) (as Figure 2a shown); in this embodiment, the outer opening layer 3 is spirally laminated and wound by low-gram-weight kraft paper or coated paper (120 - 170 grams per square meter) (as Figure 1 、 Figure 2b shown); in this embodiment, for the outer opening layer 3, since a raised part will be generated on the surface of the laminated part during spiral lamination and winding, both sides of this raised part are the kraft paper edge 6 on the face of the laminated part of the outer opening layer 3 and the kraft paper edge 6' at the bottom (i.e., Figure 1 、 Figure 2b the solid line 6 and the dotted line 6' shown), near the raised part of the outer opening layer 3 close to the sealing end cap 5, an oblique sharp-cornered tear notch 7 is pre-cut along the circumferential direction (as Figure 1 shown), the depth of this oblique sharp-cornered tear notch 7 is not less than the kraft paper thickness of the outer opening layer 3, and the distance from the oblique sharp-cornered tear notch 7 to the sealing end cap 5 is between 5 - 25 millimeters; in this embodiment, the sealing end cap 5 is a metal sealing end cap, for example, a sealing end cap 5 made of tinplate material.

[0019] In the present utility model, the spiral winding of the inner composite sealing layer 1 and the outer opening layer 3 adopts a laminated structure (as Figure 2b shown); the spiral winding of the middle reinforcing layer 2 adopts a butt-joint structure (asFigure 2a As shown). Such a structure has the following functions: First, the inner composite sealing layer 1 must adopt a spiral overlapping structure to achieve hot melt sealing or adhesive sealing at the overlapping part of the spiral winding. Otherwise, if the inner composite sealing layer 1 adopts a spiral flat overlapping structure, it will be impossible to achieve hot melt sealing or adhesive sealing at the splicing part of the spiral winding; Second, the outer opening layer 3 must adopt a spiral overlapping structure to pre-cut an inclined sharp corner easy-to-tear opening 7 at the convex part of the spiral overlapping, so that consumers can tear the outer opening layer 3. Otherwise, if the outer opening layer 3 adopts a spiral butt joint structure, it will be difficult to pre-cut the inclined sharp corner easy-to-tear opening 7; Third, the middle reinforcing layer 2 must adopt a spiral butt joint structure. When the consumer tears the outer opening layer 3 along the inclined sharp corner easy-to-tear opening 7, under the air pressure in the composite packaging can, the plastic-aluminum composite paper of the inner composite sealing layer 1 may be neatly torn at the gap of the spiral butt joint structure, so that the composite packaging can has a real easy-to-tear opening effect. Otherwise, if the middle reinforcing layer 2 adopts a spiral overlapping structure, not only will the convex part at the spiral overlapping be too high due to the relatively thick kraft card of the middle reinforcing layer 2, but also when the consumer expects to tear the outer opening layer 3 along the inclined sharp corner easy-to-tear opening 7, it is impossible to achieve the opening effect of completely tearing the composite packaging can at the spiral overlapping in any case.

[0020] Appendix Figure 3 is an enlarged schematic view of the jacket label layer 4 along the palm joint seam 8 and the perforated saddle-stitch easy-to-tear strip 9 in the present utility model. Figure 3 At least 5 implementation manners are given in, for example, in Figure 3 a, the above describes the saddle-stitch easy-to-tear strip 9 with oval perforations, and the following describes the saddle-stitch easy-to-tear strip 9 with circular perforations. This does not mean that both sides of the palm joint seam 8 on the jacket label layer must be oval perforations and circular perforations. It can also be all circular perforations or all oval perforations; Figure 3 b describes two forms of the perforated saddle-stitch easy-to-tear strip 9 with rectangular perforations and diamond-shaped perforations; Figure 3 c describes the saddle-stitch easy-to-tear strip 9 with triangular perforations. The present utility model does not exclude the saddle-stitch easy-to-tear strip 9 composed of other perforation forms, but they are all within the protection scope of the present utility model. The several saddle-stitch easy-to-tear strips 9 given above can be used alone, or combined in pairs to form two rows of saddle-stitch easy-to-tear strips 9 with two different hole shapes.

[0021] In this embodiment, the outer label layer 4 is a printed plastic sleeve with a palm-joined shape (thickness: 0.03 - 0.05 mm), which is wrapped around the outer surface of the outer opening layer 3 in a heat-shrinkable manner. Considering that uneven shrinkage of the outer label layer 4 during heat shrinkage may cause stretching deformation, a bottom-wrapping heat-shrinkage method is adopted, that is, the length of the outer label layer is the same as that of the multi-layer composite packaging can, or 3 - 8 mm longer than that of the multi-layer composite packaging can, so as to form a "bottom-wrapping" shape at both ends of the multi-layer composite packaging can during heat shrinkage. To enable consumers to conveniently open the outer label layer 4 at the set position and direction, and at the same time, the graphic content printed on the outer label layer 4 can be completely retained for reference, a row of continuous perforations is respectively arranged on both sides of the palm-joined seam 8 to form a perforated stitch-ride easy-tear strip 9; the end of the perforated stitch-ride easy-tear strip 9 corresponds to the opening 10 of the perforated stitch-ride easy-tear strip on the outer label layer 4. Taking advantage of the fact that the strength of the double-layer material at the palm-joined seam 8 on the outer label layer is doubled, and combined with the prefabricated stitch-ride holes on both sides of the palm-joined seam 8 on the outer label layer respectively, consumers can very easily open the outer label layer 4 at the set position and direction, achieving an easy-tear effect. The width of the palm-joined seam 8 on the outer label layer is 2 - 6 mm, and the width between the two rows of perforated stitch-ride easy-tear strips 9 on both sides of it is 3 - 20 mm.

[0022] The two rows of holes of the perforated stitch-ride easy-tear strip 9 can be in the form of continuous round holes, or in other hole forms such as continuous oval, rectangular, diamond-shaped or triangular holes; that is, the two rows of perforated stitch-ride easy-tear strips 9 have continuous round holes, or continuous oval holes, or continuous rectangular holes, or continuous diamond-shaped holes, or continuous triangular holes. The two rows of holes on both sides of the perforated stitch-ride easy-tear strip 9 can also be combined in pairs to form two rows of two different hole shapes; that is, the two rows of holes on both sides of the perforated stitch-ride easy-tear strip can be a combination of any two of the above hole shapes.

Claims

1. A double easy-tear opening structure of a multi-layer composite packaging can for fresh dough products, the multi-layer composite packaging can comprising from inside to outside: The inner composite sealing layer, the middle reinforcement layer, the outer opening layer and the outer label layer are mutually staggered, and are formed into a multi-layer composite cylindrical tube through staggered spiral rolling, bonding and slitting. The end caps are sealed at both ends of the multi-layer composite cylindrical tube and a tubular outer label layer is put on, which together constitute a multi-layer composite packaging can for fresh dough products. The characteristic is that the inner composite sealing layer is rolled in a spiral overlapping form, the middle reinforcement layer is rolled in a spiral opposite form, and the outer opening layer is rolled in a spiral overlapping form; at the spiral overlapping raised part of the outer opening layer, an opening mechanism of an "oblique sharp angle easy tearing opening" is arranged along the circumferential direction close to the sealing end cap, and a row of opening mechanisms of "perforated riding seam easy tearing strips" are respectively arranged on both sides of the entire palm seam of the outer label layer.

2. The double easy-tear opening structure of the multi-layer composite packaging can for fresh dough products according to claim 1, characterized in that: The inner composite sealing layer, the middle reinforcement layer and the outer opening layer in the composite packaging can are staggered and rolled in the same direction spirally to form a multi-layer composite cylindrical tube.

3. The double easy-tear opening structure of the multi-layer composite packaging container for fresh dough products according to claim 1, characterized in that: The depth of the oblique sharp-angle easy-tear opening is not less than the thickness of the outer opening layer of kraft paper.

4. The double easy-tear opening structure of the multi-layer composite packaging can for fresh dough products according to claim 1, characterized in that: The outer coat label layer adopts a printed plastic sleeve, which is wrapped on the surface of the multi-layer composite cylindrical tube in a heat shrinking manner.

5. The double easy-tear opening structure of the multi-layer composite packaging can for fresh dough products according to claim 1 or 4, characterized in that: The length of the outer label layer is consistent with that of the multi-layer composite packaging can, or is 3-8 mm longer than that of the multi-layer composite packaging can, so as to form a "bottom-wrapped" shape at both ends of the multi-layer composite packaging can during heat shrinkage.

6. The double easy-tear opening structure of the multi-layer composite packaging container for fresh dough products according to claim 1 or 4, characterized in that: The ends of the two rows of perforated tear strips correspond to the openings of the perforated tear strips on the outer coat label layer.

7. The double easy-tear opening structure of the multi-layer composite packaging container for fresh dough products according to claim 1, characterized in that: The width of the seam on the outer coat label layer is 2-6 mm, and the width between the two rows of perforations of the riding seam tear strips on both sides of the seam is 3-20 mm.

8. The double easy-tear opening structure of the multi-layer composite packaging container for fresh dough products according to claim 6, characterized in that: The width of the seam on the outer coat label layer is 2-6 mm, and the width between the two rows of perforations of the riding seam tear strips on both sides of the seam is 3-20 mm.

9. The double easy-tear opening structure of the multi-layer composite packaging container for fresh dough products according to claim 1, characterized in that: The two rows of perforated tear strips have continuous circular holes, or continuous elliptical holes, or continuous rectangular holes, or continuous diamond holes, or continuous triangular holes; the two rows of holes on both sides of the perforated tear strip can be combined in pairs to form two rows of two different hole shapes.

10. The double easy-tear opening structure of the multi-layer composite packaging container for fresh dough products according to claim 6, characterized in that: The two rows of perforated tear strips have continuous circular holes, or continuous elliptical holes, or continuous rectangular holes, or continuous diamond holes, or continuous triangular holes; the two rows of holes on both sides of the perforated tear strip can be combined in pairs to form two rows of two different hole shapes.

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