FI103269B - Closure bag with deaeration - Google Patents

Description

103269

TECHNICAL FIELD WITH SHUTCHING

The invention relates to paper bags and relates to a valve bag with a sealing film, its manufacture and use. The sacks according to the invention can be used in particular for storing products which have to be packaged as tightly as possible.

TECHNICAL BACKGROUND

In the manufacture of paper multilayer valve bags, a paper hose is formed from the paper strips, cut into lengths of the desired length and closed at its mouths by first folding inwardly narrower end tabs and wider side tabs over them. Other than the valve ends, the side strips are attached to the main strips. A separate paper shaped valve body can be added to the valve end. In addition, the valve may have a sealing tag which, after filling the bag, is pivoted and secured over the mouth of the valve to the bottom of the bag.

Moisture-proof valve bags are made of plastic-coated paper or by placing a loose plastic film between the paper layers. In particular, polyethylene has been used as the plastic.

One problem with valve sacks is that when filling the sack, air must be allowed to leave the sack. A particular problem with this is in bags with barrier films. In these cases, the barrier film has generally had to be peeled off, which substantially compromises the barrier properties of the film.

The multilayer sack can also be made permeable to air as it is disclosed in FI-A-945831. The inner layer is then highly permeable to air and has grooves on the outer surface. When filling the sack, air entering between layers passes through grooves to and from the ends of the sack. The mouth ends of the sack blank are aligned in this sack. However, this structure is not tight enough for all applications. In addition, this bag always requires a separate bottom pad in practice.

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GENERAL DESCRIPTION OF THE INVENTION

A valve bag according to claim 1 has now been invented. Preferred embodiments of the invention are set forth in the other claims.

In the bag according to the invention, a completely air and moisture-impermeable barrier membrane can be used, but when the bag is filled, the air is effectively removed from the bag. However, the bottom of the sack is also very tight due to the lime structure.

DRAWINGS

The accompanying drawings are part of a specific description of the invention. In the drawings 10 - Figure 1 shows the sack blank before forming the bottoms, - Figure 2 shows the blank with the valve body inserted, - Figure 3 shows the blank with the end strips folded, - Figure 4 shows the blank with the bottom sizing, - Figure 5 shows the blank the incoming side tabs are folded 15 - Figure 6 shows the finished sack.

DETAILED DESCRIPTION

The bag shown in the figures is made of a three-layer material. The inside has a paper inner layer 1, an outer air-impermeable barrier layer 2 and the outermost 20 a paper outer layer 3. The flattened tubular blank (Fig. 1) is provided at each end with cuts 4 to obtain side strips 5 and end strips 6. at end strips 6. Also shown in the figures are transverse side openings 7 and diagonal end openings 8 along which the flat base is formed by folding, and folding openings 9 along which the bottom is folded against the diaper.

The inner layer 1 and outer layer 3 may be suitable sack paper (e.g., 95 g / m 2). The barrier layer 2 may be a suitable plastic film (e.g., HDPE).

The barrier layer 2 is secured at each end to the inner layer 1 by transverse point gluing 10 and to the outer layer 3 by transverse point gluing 11, here also 30 point point gluing. Adhesives help to align the layers, and they also strengthen the sack as strain is applied more evenly to all layers.

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At the side strips 5, the ends of the layers are staggered so that the top of the blank has an inner layer 1 longest and an outer layer 3 shortest and a back side has an inner layer shortest and an outer layer longest. the longest and the shortest outer layer 5. The stepping of the material allows the joining of each material in the base structure.

At the end strips 6, at the top end, the inner layer 1 is slightly longer than the barrier film 2 and the outer layer 3. At the lower end, the inner layer 1 is slightly shorter than the barrier layer 2 and the outer layer 3.

10 In the next step (Fig. 2), a paper valve body 12 is attached to one end of the upper end of the blank. Its lower edge is at the side opening 7 and the upper edge extends slightly above the side strips 5. The valve body 12 is glued to the end strip 6 on both sides slightly outside the cut 4 by a longitudinal adhesive strip 13. The lower end of the valve body 12 has a fold on the inside. Its upper edge 15 is flush with the upper edge of the outer layer 3 of the end strip 6. The valve body 12 is further marked with a line 13 along which the valve body is folded along the side strip 5 along the side opening 7.

In the next step (Fig. 3), the front side flaps 5 are folded along the folding nibbling 9, while the end flaps 6 are folded inwardly along the end flaps 20 8. In addition, the sides of the valve body 12 are folded inwardly and laterally over the folded sides. In the region of the double end edge of the valve body 12, the adhesive strip 15 is: slightly wider. The side edges of the valve body 12 are then pivoted backwards and adhered tightly to the inner layer of the side strips 5 of the end strip 6.

In the next step (Fig. 4), adhesive strips are formed by means of which the bottoms are closed. On the side-facing side strip 5.1, where the inner layer 1 is the longest, end-strips 16.1 extend from the outer surface of the end strip 6 to the inner surface of the side strip 16.1. On the incoming side strip 5.2, where the inner layer 1 is the shortest, similar shorter end adhesive strips 16.2 are formed. Further, the end adhesive strips 16.2 are joined along the edge of the inner layer 1 with a narrower inner side adhesive strip 17. At the end of the outer layer 3, a narrow end to end outer adhesive strip 18 is formed on the inner side.

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In the next step (Fig. 5), the side strips 5.1 coming down from the bottom are folded, whereby the inner surface of the inner layer 1 tightly adheres to the end strips 6 and the valve body 12, respectively, 5.1 to the outer layer by the outer side adhesive strip 18 and the inner layer 1 to the end strip 6, at the valve angle to the valve body 12, and the lower side strip to the inner layer by the end adhesive strips 16.2 and the inner side strip 17.

Thus, in the base structure, each paper layer 1 and 3 is glued sack lengthwise it-10 against the wall (staggering) by glue seams 17 and 18. The stepped barrier layer 2 is longitudinally unglued but cross-glued to the paper layers. In this way, the free non-adhesive well structure allows air to escape from the ends of the base, but interleaved to form a moisture barrier to the base structure. The barrier layer can be glued with cheap process sizing; expensive and 15 specialty stains are not needed.

Gluing the corners of the soles with seams 16.1 and 16.2 seals and seals the structure, but allows dust-free air to escape between the layers 1 and 2 at the ends of the sole.

The bottom structure is completely sealed inward with the exception of the valve having a filling opening 20 between the outer layer of the end strip 6 and the valve body. Inside the filled sack, the material inside presses the end strip 6 tightly against the valve body 12. If desired, the valve mouth may be further separately closed with an orifice closure over the bottom. Due to the overlapping of materials, the bottom has an intact barrier film 2 at each point.

When filling the sack, air passes from the sack between the inner layer 1 and the barrier layer 2, from where it comes out of their ends at the bottom of the sack. In the soles, air passes between the side strips 5.1 and 5.2 to the ends from which it exits (Fig.5). In order to facilitate the passage of air, the outer surface of the inner layer 1 may be grooved, but even a smooth surface paper will work.

30 Venting is very effective when air passes through both sides of the sack at each end.

A bottom plate is not required to form the exhaust air duct or to increase the strength of the bag.

5 103269 The sacks can be made on hose and bottom machines of a conventional bag making line with inserts to make the necessary cuts, overlaps and gluing. No extra material is needed.

The sack is especially suitable for materials that need to be protected as much as possible from the outside air (eg cocoa) or to prevent leakage from the sack (eg chemicals harmful to the environment).

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Claims (6)

6 103269 1. A closure bag having a tubular jacket having an air-permeable but dust-filterable paper inner layer (1), a separate air-impermeable barrier layer (2), and one or more outer paper layers (3) 5 on each end having flat base having inwardly folded end strips (6) and folded over side strips (5.1, 5.2), characterized in that in the bottom side strip (5.1) the inner layer (1) is longer than the barrier layer and the outer layer (3) is shorter than the barrier layer (2) and in the top side strip (5.2) the inner layer (1) is shorter than the barrier layer (2) and the outer layer (3) is longer than the barrier layer (2) so that the inner surface of the inner layer (1) of the top side strip (5.2) is glued the outer surface of the inner layer (1) of the lower side strip (5.1) with an inner side strip (17) that the inner surface of the outer layer (3) of the upper side strip (5.2) is glued against the outer surface of the side strip (5.1) in the outer side adhesive strip (18), whereby between the inner layer (1) and the barrier layer (2), air 15 can escape from the bottom between the side strips (5.1, 5.2). 2. Säck enligt patentkrav 1, pseudnetnk av att luft avgär genom bottnens var-20 dera tendon. A sack according to claim 1, characterized in that air can escape from both ends of the sole. 3. Säck enligt patentkrav 1 eller 2, the strain gonad av att luft avgär genome säckens vardera gang. ; 4. Säck enligt patentkrav 3, a turnbuckle av att luft kan passera mellan det ime skiktet (1) and a spärrskiktet (2) on the crotch strap to the crotch strap. A sack according to claim 1 or 2, characterized in that air can be expelled from each end of the sack. A sack according to claim 3, characterized in that air passes between the inner layer (1) of the ground and the barrier layer (2) on each side of the sack. 5. Säck enligt face av patent kraven 1-4, kanknetecknad av att spärrskiktet (2) limmats vid det ime skiktet (1) eller det yttre skiktet (3) i manteländen med tvär-30 gäende point lymph (10/11). A sack according to any one of claims 1 to 4, characterized in that the barrier layer (2) is glued to the inner layer (1) or outer layer (3) by transverse spot gluing (10/11). A sack according to any one of claims 1 to 5, characterized in that the bottom has no end help. 7 103269 ^ 1. Förslutningssäck med en slangfonnad mantel som har ettim skikt (1) av papper som släpper genome luftmen filtrerar Damm, utanför detta et skilt luftogenom-5 trängligt spärrskikt (2), och utanför detta ett eller flera y. skikt (3) av papper, varnishes i darder änden har en plan botten med inätvänän ändflikar (6) och sidoflikar (5.1, 5.2) vikta head, reversing tongue av att i den underliggande sidofli-ken (5.1) i bottnen är det ime skiktet (1) länre än spärrskiktet och det yttre skiktet (3) kartare än spärrskiktet (2) och i den ovanpä belägna sidofliken (5.2) and det ime 10 skiktet (1) kartare än spärrskiktet (2) och det yttre skiktet (2) 3) the slacker (2), the inner skeleton (1), the oval belgium sidofliken (5.2), the lim-mats mot ytterytan av the skeletal skeleton (5.1), the medieval skeleton (5.1) limremsa (17), att innerytan av det yttre skiktet (3) av den ovanpä belägna sidofliken (5) .2) lymphatic motility of the skin (5.1), medication of 15 ytre limremsa (18), coloring of the skull (1) and spärrskiktet (2) in the bottom of the account of the breast (5.1, 5.2) och därifrän ut genom bottnens tendon. 6. Säck enligt face av patentkraven 1-5, folds of the face av att bottnen inte har face.