Exhaust backseal bag
By incorporating isolation strips and vents into the packaging bag, the design of the vented back-sealed bag solves the problems of bag breakage and aesthetics, achieving high load-bearing capacity, compressive strength, and effective sealing of powder materials, thus improving the convenience of transportation and stacking.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- ZHEJIANG CHOVYTING MASCH CO LTD
- Filing Date
- 2025-08-30
- Publication Date
- 2026-07-14
AI Technical Summary
Existing packaging bags contain a large amount of gas after filling, which makes the bags prone to breakage, stacking, and transportation inconvenient. In addition, the outer venting holes affect the appearance and are easily damaged.
Design an exhaust back-sealed bag with an isolation strip inside the bag cavity, an air inlet and an exhaust outlet located at the transverse sealing edge, the isolation strip sealed with the back cover, and the exhaust outlet located at the unsealed part of the transverse sealing edge. Use the same film material to increase the load-bearing capacity and compressive strength of the bag, and divide the airflow channel through the channel sealing group to reduce the loss of powder material.
It achieves high load-bearing and compressive strength of the bag, reduces the chance of breakage, maintains its aesthetic appeal, and reduces the discharge of powder materials through a meandering airflow channel, improving the convenience of transportation and stacking.
Smart Images
Figure CN224492050U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of packaging bags, specifically a vented back-sealed bag. Background Technology
[0002] The sealed packaging bags contain a large amount of gas, which is not only detrimental to the stacking, storage, and transportation of the bags, but also makes them prone to rupture under external pressure. Publication number CN208264892U describes a single-channel venting FFS packaging bag with venting function. It utilizes the overlapping area of the inner and outer layers to form a single venting channel, allowing gas inside the bag to escape through venting holes in both layers. However, the outer venting holes are located on a flat side, i.e., the front or back of the bag, and are knife-edge type venting holes. This significantly reduces the load-bearing capacity and compressive strength of the bag surface, making the outer venting holes prone to damage and affecting the bag's aesthetics. Utility Model Content
[0003] In view of the technical problems existing in the background art, the technical problem solved by this utility model is to provide a venting back-sealing bag that not only has a venting function, but also has high load-bearing and compressive strength, reducing the probability of packaging bag damage.
[0004] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: the exhaust back-sealing bag is characterized by comprising a front bag surface, a back cover, an isolation strip, and a bag cavity;
[0005] The front bag and the back cover are connected to form a bag cavity. The front bag does not have a longitudinal seal, while the back cover has a longitudinal seal. The top and bottom ends of the front bag and the back cover have transverse seals.
[0006] The isolation strip is set inside the bag cavity. The two ends of the isolation strip extend longitudinally and are fixed by transverse sealing. The isolation strip and the back cover form an exhaust cavity. The isolation strip is provided with an air inlet for the gas in the bag cavity to enter the exhaust cavity. Each of the two transverse sealing edges is provided with at least one exhaust port for the gas in the exhaust cavity to be discharged.
[0007] The isolation strip of this utility model is sealed with the back cover, and the front of the bag remains intact, making it more aesthetically pleasing. At the same time, the vent is located at the horizontal sealing edge, that is, the part where the isolation strip and the back cover are not sealed at the horizontal sealing edge is the vent. In this way, the bag itself will not be damaged, and the bag has high load-bearing and compressive strength.
[0008] Preferably, the front bag cover, back cover, and isolation strip are integrated into one piece, which is the main material of the film.
[0009] The main film material has a first end and a second end at its two transverse ends. The first end covers the second end, and the end of the first end is longitudinally sealed to the outer surface of the second end to form a longitudinal seal. The part of the second end inside the bag body serves as an isolation strip. Using the same main film material facilitates processing and reduces material waste.
[0010] Preferably, the end of the second end is longitudinally sealed to the inner surface of the first end, forming the first sealing edge;
[0011] The space between the longitudinal sealing edge and the first sealing edge is an exhaust chamber.
[0012] Preferably, the second end is folded inside the bag cavity and along the edge of the longitudinal sealing edge. The second end is divided into an external second end outside the bag body and a folded second end inside the bag body. The folded second end is longitudinally sealed with the inner surface of the external second end, which is the second sealing edge.
[0013] The space between the longitudinal sealing edge and the second sealing edge is an exhaust chamber.
[0014] Preferably, the front bag cover and the back cover are integrated as a single piece of film material, and the isolation strip is made of film material.
[0015] The two transverse ends of the main film material are the first end and the second end, respectively. The first end and the second end are longitudinally sealed with one end of the auxiliary film material to form two longitudinal sealing edges, namely the first longitudinal sealing edge and the second longitudinal sealing edge. The other end of the auxiliary film material is longitudinally sealed with the inner surface of the first end to form the third sealing edge. The space between the third sealing edge and the first longitudinal sealing edge is an exhaust cavity.
[0016] Preferably, the front bag cover and the back cover are integrated as a single piece of film material, and the isolation strip is made of film material.
[0017] The two transverse ends of the main film material are the first end and the second end, which are longitudinally sealed together to form a longitudinal sealing edge. The two ends of the auxiliary film material are longitudinally sealed with the first end of the main film material, or the two ends of the auxiliary film material are longitudinally sealed with the second end of the main film material, or the two ends of the auxiliary film material are longitudinally sealed with the first end and the second end of the main film material respectively to form a fourth sealing edge and a fifth sealing edge. The space between the fourth sealing edge and the fifth sealing edge is an exhaust cavity.
[0018] Preferably, the isolation strip and the back cover are provided with at least one set of channel sealing groups, which divide the exhaust chamber into at least two communicating airflow channels, and the channel sealing groups stagger the air inlet and the exhaust outlet.
[0019] A set of channel sealing edges is provided with at least two longitudinally spaced channel sealing edges, and there is a vent between adjacent channel sealing edges in the same set;
[0020] The gas entering through the inlet enters an airflow channel, passes through a vent and another airflow channel, and finally exits through the exhaust port. Powder material inside the bag is easily discharged with the airflow. By setting a channel seal, not only is the length of gas flow increased, but the airflow is also blocked by the channel seal, causing the powder to remain inside the bag and reducing powder discharge from the packaging bag.
[0021] Preferably, the channel sealing assembly is provided in at least two sets, with an airflow channel between adjacent channel sealing assemblies, and the air vents of adjacent sets are longitudinally staggered. The airflow channel is meandering, which provides better blocking effect for powder materials. Attached Figure Description
[0022] Figure 1 This is a schematic diagram of the present invention.
[0023] Figure 2 This is a schematic diagram of Embodiment 1 of the present utility model.
[0024] Figure 3 This is a cross-sectional schematic diagram of Embodiment 1 of the present utility model.
[0025] Figure 4 This is a cross-sectional schematic diagram of Embodiment 2 of the present invention.
[0026] Figure 5 This is a cross-sectional schematic diagram of Embodiment 3 of the present invention.
[0027] Figure 6 This is a cross-sectional schematic diagram of Embodiment 4 of this utility model.
[0028] Reference numerals: 1. Front of bag; 2. Back cover; 3. Bag cavity; 4. Insulation strip; 5. Exhaust chamber; 6. Longitudinal seal; 7. Transverse seal; 8. Air inlet; 9. Exhaust outlet; 10. Channel seal; 11. First airflow channel; 12. Second airflow channel; 13. Third airflow channel; 14. Vent; 15. First seal; 16. Second seal; 17. Third seal; 18. Fourth seal; 19. Fifth seal; 20. Main film material; 21. First end; 22. Second end; 23. Detailed Implementation
[0029] The following description, in conjunction with the accompanying drawings, details the embodiments and working principles of this utility model. A back-sealed bag, also known as a center-sealed bag, is a packaging method where the back of the bag is sealed; that is, the front of the bag is seamless, while the back sides are sealed.
[0030] This type of vented back-sealed bag includes a front bag face 1, a back cover 2, an isolation strip 4, and a bag cavity 3, with the bag cavity 3 located between the front bag face and the back cover. The front bag face 1 does not have a longitudinal seal, while the back cover 2 has a longitudinal seal 6. The top and bottom ends of the front bag face and the back cover have transverse seals 7. The front bag face remains intact and can be used for printing patterns and product markings. If the front bag face 1 is made of transparent material, the material inside the bag can be fully seen. The isolation strip 4 is disposed inside the bag cavity 3, extending longitudinally at both ends and fixed by the transverse seals 7. The isolation strip 4 and the back cover 2 form a venting cavity 5. The isolation strip 4 has an air inlet 8 for gas from the bag cavity 3 to enter the venting cavity 5. Each of the two transverse seals 7 has at least one vent 9 for gas from the venting cavity 5 to exit. At least one part of the isolation strip 4 and the back cover 2 at the transverse seal 7 is not sealed; this unsealed part is the vent 9. Except for the unsealed vent 9, the front bag face, back cover, and isolation strip at the transverse seals are all sealed. Figure 1 In this invention, both transverse sealing edges 7 are provided with an exhaust port 9. Gas inside the bag cavity 3 enters the exhaust chamber 5 through the air inlet 8, and gas inside the exhaust chamber is discharged through the exhaust port 9. To prevent the material in the bag from pressing the isolation strip 4 and the back cover 2 together and affecting the exhaust, the filled and sealed bags should be stacked with the back cover 2 facing upwards, which facilitates the exhaust of gas inside the bag. The transverse sealing edges 7, longitudinal sealing edges 6, and the sealing method described in this invention can be heat-sealed with a sealing knife, glued, or ultrasonically sealed. Because the isolation strip 4 is sealed to the back cover 2, regardless of whether the sealing edge is heat-sealed with a sealing knife, ultrasonically sealed, or glued, it will not affect the front of the bag, and the front of the bag will remain intact. At the same time, the exhaust port 9 is located at the transverse sealing edge 7, so the bag itself will not be damaged, and the bag has high load-bearing and compressive strength.
[0031] If the material filled in the packaging bag is powder, some powder will follow the gas from the air inlet 8 into the exhaust chamber 5, and then be discharged from the exhaust port 9, causing powder loss. The discharged powder will also affect the processing environment. To reduce powder discharge, the isolation strip 4 and the back cover 2 are provided with at least one set of channel sealing groups. The channel sealing groups divide the exhaust chamber into at least two communicating airflow channels, and the air inlet and exhaust port are staggered. Each set of channel sealing groups has at least two longitudinally spaced channel sealing edges 10, with vents between adjacent channel sealing edges in the same group, and the airflow channels are connected through the vents. There are at least two sets of channel sealing groups, with airflow channels between adjacent channel sealing groups. The vents of adjacent groups are longitudinally staggered, and the channel sealing groups form a meandering airflow channel. After the gas enters from the air inlet 8, it cannot be discharged directly from the exhaust port 9, but passes through the airflow channel and then is discharged from the exhaust port 9, thus reducing the discharge of powder.
[0032] Figure 1In the design, the air inlet 8 is located on the right side, and the exhaust outlets 9 are located at both ends on the left. Two sets of channel sealing groups are provided between the air inlet 8 and the exhaust outlets 9. The exhaust chamber 5 is divided into three airflow channels: the first airflow channel 11, the second airflow channel 12, and the third airflow channel 13, from right to left. Gas inside the bag cavity 3 enters the first airflow channel 11 through the air inlet 8. Due to the obstruction of the first set of channel sealing groups, it can only enter the second airflow channel 12 between the two sets of channel sealing groups through the vent 14, and then enter the third airflow channel 13 through the vent 14 of the second set of channel sealing groups, before being discharged from the exhaust outlets 9 at both ends. Even if powdered material inside the bag enters the exhaust chamber 5 through the air inlet 8, it is blocked by the detour of the channel sealing groups and remains within the airflow channels, thus preventing contamination of the packaging environment.
[0033] The isolation strip 4 can be integrated with the front bag 1 and the back cover 2, or they can be separate parts. The preferred embodiment will be further described below with reference to the accompanying drawings.
[0034] See attached Figure 2 and 3 Example 1: The front bag face 1, back cover 2, and isolation strip 4 are integrated into a single unit, forming the main film material 20. The main film material 20 has a first end 21 and a second end 22 at its two transverse ends. The first end covers the second end, and the end of the first end 21 is longitudinally sealed to the outer surface of the second end 22 to form a longitudinal seal 6. The portion of the second end 22 inside the bag body forms the isolation strip 4. The side with the longitudinal seal 6 is the back cover 2, and the side without the longitudinal seal 6 is the front bag face 1. The end of the second end 22 is longitudinally sealed to the inner surface of the first end 21 to form a first seal 15. An exhaust chamber 5 is located between the longitudinal seal 6 and the first seal 15.
[0035] See attached Figure 4 In Embodiment Two, similarly, the front bag face 1, back cover 2, and isolation strip 4 are integrated into a single unit, forming the main film material 20. The two transverse ends of the main film material 20 are a first end 21 and a second end 22, respectively. The first end covers the second end, and the end of the first end 21 is longitudinally sealed to the outer surface of the second end 22 to form a longitudinal seal edge 6. The portion of the second end 22 inside the bag body forms the isolation strip 4. The side with the longitudinal seal edge 6 is the back cover 2, and the side without the longitudinal seal edge 6 is the front bag face 1. The second end 22 is folded within the bag cavity 3 along the edge of the longitudinal seal edge 6. The second end 22 is divided into an external second end outside the bag body and a folded portion inside the bag body. The folded portion of the second end is longitudinally sealed to the inner surface of the external second end, forming a second seal edge 16. An exhaust cavity 5 is located between the longitudinal seal edge 6 and the second seal edge 16.
[0036] See attached Figure 5In embodiment three, the front bag face 1 and the back cover 2 are integrated as a single piece, forming the main film material 20, while the isolation strip is made of a secondary film material. The main film material 20 has two transverse ends, a first end 21 and a second end 22, which are longitudinally sealed to one end of the secondary film material to form two longitudinal sealing edges 6, namely the first longitudinal sealing edge and the second longitudinal sealing edge. The other end of the secondary film material is longitudinally sealed to the inner surface of the first end 21, forming a third sealing edge 17. A venting cavity 5 is located between the third sealing edge 17 and the first longitudinal sealing edge. Here, the secondary film material serves partly as the back cover and partly as the isolation strip 4. Similarly, this part within the bag body is the isolation strip 4. The side with the longitudinal sealing edge 6 is the back cover 2, and the side without the longitudinal sealing edge 6 is the front bag face 1.
[0037] See attached Figure 6 In Example 4, the front bag face 1 and the back cover 2 are integrated as a single piece, forming a main film material 20. The insulating strip 4 is made of a secondary film material. The two transverse ends of the main film material 20 are a first end 21 and a second end 22, which are longitudinally sealed together to form a longitudinal sealing edge 6. The two ends of the secondary film material are longitudinally sealed to the first end of the main film material, or the two ends of the secondary film material are longitudinally sealed to the second end of the main film material, or the two ends of the secondary film material are longitudinally sealed to the first and second ends of the main film material respectively, forming a fourth sealing edge 18 and a fifth sealing edge 19. An exhaust chamber 5 is located between the fourth sealing edge 18 and the fifth sealing edge 19. (Appendix) Figure 6 In this process, the two ends of the film auxiliary material are longitudinally sealed to the first end of the film main material to form a fourth sealing edge 18 and a fifth sealing edge 19. Here, the film auxiliary material is the isolation strip 4, the side with the longitudinal sealing edge 6 is the back cover 2, and the side without the longitudinal sealing edge 6 is the front bag side 1.
Claims
1. A vented back-sealed bag, characterized in that: It includes the front cover, back cover, isolation strips, and bag cavity; The front bag and the back cover are connected to form a bag cavity. The front bag does not have a longitudinal seal, while the back cover has a longitudinal seal. The top and bottom ends of the front bag and the back cover have transverse seals. The isolation strip is set inside the bag cavity. The two ends of the isolation strip extend longitudinally and are fixed by transverse sealing. The isolation strip and the back cover form an exhaust cavity. The isolation strip is provided with an air inlet for the gas in the bag cavity to enter the exhaust cavity. Each of the two transverse sealing edges is provided with at least one exhaust port for the gas in the exhaust cavity to be discharged.
2. The exhaust back-sealing bag according to claim 1, characterized in that: The front bag surface, back cover, and isolation strip are integrated into one piece, which is the main material of the film. The two transverse ends of the main film material are a first end and a second end, respectively. The first end covers the second end, and the end of the first end is longitudinally sealed with the outer surface of the second end to form a longitudinal sealing edge. The part of the second end inside the bag is the isolation strip.
3. The exhaust back-sealing bag according to claim 2, characterized in that: The end of the second end is longitudinally sealed to the inner surface of the first end, forming the first sealing edge; The space between the longitudinal sealing edge and the first sealing edge is an exhaust chamber.
4. The exhaust back-sealing bag according to claim 2, characterized in that: The second end is folded inside the bag cavity and along the edge of the longitudinal sealing edge. The second end is divided into an external second end outside the bag body and a folded second end inside the bag body. The folded second end is longitudinally sealed with the inner surface of the external second end, which is the second sealing edge. The space between the longitudinal sealing edge and the second sealing edge is an exhaust chamber.
5. The exhaust back-sealing bag according to claim 1, characterized in that: The front and back covers are integrated as a single piece of film material, while the isolation strip is made of film material. The two transverse ends of the main film material are the first end and the second end, respectively. The first end and the second end are longitudinally sealed with one end of the auxiliary film material to form two longitudinal sealing edges, namely the first longitudinal sealing edge and the second longitudinal sealing edge. The other end of the auxiliary film material is longitudinally sealed with the inner surface of the first end to form the third sealing edge. The space between the third sealing edge and the first longitudinal sealing edge is an exhaust cavity.
6. The exhaust back-sealing bag according to claim 1, characterized in that: The front and back covers are integrated as a single piece of film material, while the isolation strip is made of film material. The two transverse ends of the main film material are the first end and the second end, which are longitudinally sealed together to form a longitudinal sealing edge. The two ends of the auxiliary film material are longitudinally sealed with the first end of the main film material, or the two ends of the auxiliary film material are longitudinally sealed with the second end of the main film material, or the two ends of the auxiliary film material are longitudinally sealed with the first end and the second end of the main film material respectively to form a fourth sealing edge and a fifth sealing edge. The space between the fourth sealing edge and the fifth sealing edge is an exhaust cavity.
7. The exhaust back-sealing bag according to any one of claims 1-6, characterized in that: The isolation strip and the back cover are provided with at least one set of channel sealing groups, which divide the exhaust chamber into at least two communicating airflow channels, and the channel sealing groups stagger the air inlet and the exhaust outlet.
8. The exhaust back-sealing bag according to claim 7, characterized in that: A set of channel sealing edges is provided with at least two longitudinally spaced channel sealing edges, and there is a vent between adjacent channel sealing edges in the same set; The gas entering through the air inlet enters an airflow channel, passes through the vent and another airflow channel, and is finally discharged through the exhaust port.
9. The exhaust back-sealing bag according to claim 8, characterized in that: The channel sealing group is provided in at least two groups, and there is an airflow channel between adjacent channel sealing groups. The air vents of adjacent groups are longitudinally staggered.