Preformed in-mold label and production equipment thereof

Abstract

The present invention relates to the technical field of food packaging production, and specifically to a preformed in-mold label and its production equipment. The preformed in-mold label includes an adhesive layer, a barrier layer and a printing layer. The adhesive layer, the barrier layer and the printing layer are all made into preformed shapes. The adhesive layer, the barrier layer and the printing layer are distributed in sequence from the inside to the outside. The production equipment includes a preforming device and a laminating device. The laminating device includes a machine base, a pressure head, a plurality of heating coils, a pressure head driving mechanism and a reverse mold. The outer wall of the pressure head is bonded to the inner wall of the adhesive layer, and a vent hole is opened on the top of the pressure head. The inner wall of the reverse mold is bonded to the outer wall of the printing layer. The pressure head is connected to the pressure head driving mechanism, and a plurality of heating coils are arranged in sequence in the pressure head. The substantial effect of the present invention is that the adhesive layer can facilitate the bonding of the in-mold label to the food packaging, the printing layer is convenient for printing, and the barrier layer between the adhesive layer and the printing layer can effectively block oxygen and water, protect the food therein, and keep it fresh for a longer time.

Description

Technical Field

[0001] The invention relates to the technical field of food packaging production, and in particular to a preformed in-mold label and production equipment thereof. Background Art

[0002] The so-called in-mold label is to put the printed trademark label image sheet (with hot melt adhesive on the back) directly into the mold area of ​​the plastic molding machine, and combine the label and the container through blow molding or injection molding to form a complete packaging container. The biggest feature of using in-mold label containers is that the label and the bottle body are on the same surface, and the color image of the label feels like it is directly printed on the surface of the bottle body. As a new form of label packaging, in-mold labels have been popular in developed countries in Europe and the United States for many years. In recent years, they have also been favored by more and more printing substrate suppliers, label manufacturers and end consumers in China. In-mold labels play an important role in food logistics, anti-counterfeiting, identification and other aspects. However, the functions of current in-mold labels are still relatively simple and cannot meet the food packaging requirements for food preservation. In the hot pressing process, it is easy to affect the packaging sealing of the food itself. Resulting in a decrease in the water and oxygen barrier properties of the packaging. Therefore, it is necessary to improve the in-mold label to solve the problem of low sealing and barrier properties of food packaging. Summary of the invention

[0003] The technical problem to be solved by the present invention is that the water and oxygen barrier performance of food packaging currently using in-mold labels is not high. A preformed in-mold label and its production equipment are proposed, and a barrier layer is used to improve the water and oxygen barrier performance of food packaging.

[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is: a preformed in-mold label, including an adhesive layer, a barrier layer and a printing layer, wherein the adhesive layer, the barrier layer and the printing layer are all made into a preformed shape, and the adhesive layer, the barrier layer and the printing layer are distributed in sequence from the inside to the outside.

[0005] Preferably, the barrier layer is made of polyvinylidene chloride, ethylene-vinyl alcohol copolymer, polyester resin, polyethylene naphthalate or aluminum oxide.

[0006] Preferably, the adhesive layer is made of hot melt adhesive, and a label is printed on the outer wall of the printing layer.

[0007] A device for producing preformed in-mold labels as described above, comprising a preforming device and a laminating device, wherein the preforming device respectively forms an adhesive layer, a barrier layer and a printing layer into preformed shapes, wherein the preformed shapes allow gaps between the adhesive layer, the barrier layer and the printing layer, and the laminating device comprises a machine base, a pressure head, a plurality of heating coils, a pressure head driving mechanism and a reverse mold, wherein the outer wall of the pressure head is in contact with the inner wall of the adhesive layer, an air hole is provided on the top of the pressure head, the inner wall of the reverse mold is in contact with the outer wall of the printing layer, the reverse mold is mounted on the machine base, the pressure head driving mechanism is mounted on the machine base, the pressure head is connected to the pressure head driving mechanism, and a plurality of the heating coils are arranged in sequence in the pressure head.

[0008] Preferably, it also includes a hydraulic pump, a liquid tank, a liquid supply pipe, a solenoid valve and a controller. The inverted mold includes a mold body, a leakage hole, a liquid cavity, a liquid supply port, an air outlet, an air valve and a pressure sensor. The front part of the mold body has a mold cavity, the rear part of the mold body has a hollow liquid cavity, the inner wall of the mold cavity is in contact with the outer wall of the barrier layer or the printing layer, a plurality of leakage holes are opened at the bottom of the mold cavity, the leakage holes connect the mold cavity and the liquid cavity, the pressure sensor is installed on the mold body to detect the liquid pressure in the liquid cavity, the rear part of the mold body has a liquid supply port, the liquid supply port connects the liquid supply pipe and the liquid cavity, the liquid supply pipe is connected to the hydraulic pump through the solenoid valve, the hydraulic pump is connected to the liquid tank, and the solenoid valve and the pressure sensor are both connected to the controller.

[0009] Preferably, the adhesive layer is put into the pressure head, and then the barrier layer is put into the adhesive layer, the mold cavity is placed vertically, the mold cavity is pre-filled with liquid, and when the printing layer is gradually put into the mold cavity, the controller controls the air valve to open, and the controller controls the solenoid valve to open a first opening, pushing the printing layer so that the liquid flows into the liquid tank through the liquid supply pipe. When the printing layer is completely put into the mold cavity, the controller controls the air valve to close, and after the controller turns on the hydraulic pump to extract part of the liquid, the inverted mold is placed horizontally, and the pressure head driving mechanism drives the pressure head to push the adhesive layer and the barrier layer into the printing layer, and makes the top of the pressure head pass through the adhesive layer, the barrier layer and the printing layer to press against the bottom of the mold cavity, and use the hydraulic pump to fill the liquid until the pressure increase detected by the pressure sensor exceeds the set threshold, and then close the solenoid valve, and turn on the heating coils in sequence from the top to the bottom of the pressure head, so that the adhesive layer expands in sequence from the bottom to the top and presses the barrier layer and the printing layer, and then closes the heating coil, and the pressure head driving mechanism drives the pressure head to withdraw the mold to complete the production of the in-mold label. The prefabricated shape allows gaps between the bonding layer, the barrier layer and the printing layer. When the top of the pressure head passes through the bonding layer, the barrier layer and the printing layer and presses against the bottom of the mold cavity, the bottoms of the bonding layer, the barrier layer and the printing layer are tightly attached, and there are gaps on the sides, so that the heating coils are opened in sequence from the top to the bottom of the pressure head, so that the part of the bonding layer close to the bottom expands first and presses the barrier layer and the printing layer, so that the small amount of air remaining on the side can be gradually squeezed out, so that the bonding layer, the barrier layer and the printing layer are tightly attached.

[0010] The substantial effects of the present invention are: the adhesive layer can facilitate the bonding of the in-mold label to the food packaging, the printing layer is convenient for printing, and the barrier layer between the adhesive layer and the printing layer can effectively block oxygen and water, protect the food therein, and keep it fresh for a longer time. Through the production equipment provided by the present invention, the adhesive layer, the barrier layer and the printing layer of the in-mold label produced are tightly fitted, no air is left, and the aesthetics of the label is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is a schematic diagram of the preformed in-mold labeling structure of Example 1;

[0012] Figure 2 This is a schematic diagram of the cross-sectional structure of a preformed in-mold label in Example 1;

[0013] Figure 3 This is a schematic diagram of the partial structure of the preformed in-mold labeling in Example 1;

[0014] Figure 4 It is a partial schematic diagram of the preformed in-mold labeling production equipment of Example 1;

[0015] Figure 5 This is a schematic diagram of the cross-sectional structure of the inverted mold of Example 2.

[0016] Among them: 11, bonding layer, 12, barrier layer, 13, printing layer, 20, pressure head, 21, air vent, 30, reverse mold, 31, mold cavity, 32, liquid leakage hole, 33, pressure sensor, 34, air outlet, 35, liquid supply port, 36, liquid cavity. DETAILED DESCRIPTION

[0017] The specific implementation of the present invention will be further described below through specific examples in conjunction with the accompanying drawings.

[0018] Embodiment 1:

[0019] A preformed in-mold label, see attached Figure 1 and attached Figure 2 , including an adhesive layer 11, a barrier layer 12 and a printing layer 13, the adhesive layer 11, the barrier layer 12 and the printing layer 13 are all made into a prefabricated shape, and the adhesive layer 11, the barrier layer 12 and the printing layer 13 are arranged in sequence from the inside to the outside. The barrier layer 12 is made of polyvinylidene chloride, ethylene-vinyl alcohol copolymer, polyester resin, polyethylene naphthalate or aluminum oxide. Please refer to the attached Figure 3 The adhesive layer 11 is made of hot melt adhesive, and a label is printed on the outer wall of the printing layer 13 .

[0020] An apparatus for producing preformed in-mold labels as described above, see attached Figure 4, including a preforming device and a laminating device. The preforming device respectively forms the adhesive layer 11, the barrier layer 12 and the printing layer 13 into preformed shapes. The preformed shapes allow the adhesive layer 11, the barrier layer 12 and the printing layer 13 to have gaps. The laminating device includes a machine base, a pressing head 20, a plurality of heating coils, a pressing head driving mechanism and a reverse mold 30. The outer wall of the pressing head 20 is in contact with the inner wall of the adhesive layer 11. An air hole 21 is provided on the top of the pressing head 20. The inner wall of the reverse mold 30 is in contact with the outer wall of the printing layer 13. The reverse mold 30 is installed on the machine base. The pressing head driving mechanism is installed on the machine base. The pressing head 20 is connected to the pressing head driving mechanism. A plurality of heating coils are arranged in sequence in the pressing head 20.

[0021] The beneficial technical effects of this embodiment are: the adhesive layer 11 can facilitate the bonding of the in-mold label to the food packaging, the printing layer 13 is convenient for printing, and the barrier layer 12 between the adhesive layer 11 and the printing layer 13 can effectively block oxygen and water, protect the food therein, and keep it fresh for a longer time.

[0022] Embodiment 2:

[0023] A device for producing preformed in-mold labels as described above. This embodiment is based on the first embodiment, and the structure of the reverse mold 30 is specifically improved. Please refer to the attached Figure 5 The present embodiment further includes a hydraulic pump, a liquid tank, a liquid supply pipe, a solenoid valve and a controller. The inverted mold 30 includes a mold body, a leakage hole 32, a liquid cavity 36, a liquid supply port 35, an air outlet 34, an air valve and a pressure sensor 33. The front of the mold body has a mold cavity 31, and the rear of the mold body has a hollow liquid cavity 36. The inner wall of the mold cavity 31 is in contact with the outer wall of the barrier layer 12 or the printing layer 13. A plurality of leakage holes 32 are opened at the bottom of the mold cavity 31, and the leakage holes 32 connect the mold cavity 31 and the liquid cavity 36. The pressure sensor 33 is installed on the mold body to detect the liquid pressure in the liquid cavity 36. The rear of the mold body has a liquid supply port, and the liquid supply port connects the liquid supply pipe and the liquid cavity 36. The liquid supply pipe is connected to the hydraulic pump through the solenoid valve, and the hydraulic pump is connected to the liquid tank. The solenoid valve and the pressure sensor 33 are both connected to the controller.

[0024] The method of using the present embodiment is as follows: insert the adhesive layer 11 into the pressure head 20, and then insert the barrier layer 12 into the adhesive layer 11, place the mold cavity 31 vertically, pre-fill the mold cavity 31 with liquid, and when the printing layer 13 is gradually placed in the mold cavity 31, the controller controls the air valve to open, and the controller controls the solenoid valve to open a first opening, pushing the printing layer 13 so that the liquid flows into the liquid tank through the liquid supply pipe. When the printing layer 13 is completely placed in the mold cavity 31, the controller controls the air valve to close, and after the controller turns on the hydraulic pump to extract part of the liquid, the reverse mold 30 is placed horizontally, and the air remaining in the liquid cavity will float to the side and break away from the contact with the printing layer, and the pressure is pressed. The head driving mechanism drives the pressure head 20 to push the adhesive layer 11 and the barrier layer 12 into the printing layer 13, and makes the top of the pressure head 20 pass through the adhesive layer 11, the barrier layer 12 and the printing layer 13 to press against the bottom of the mold cavity 31, and uses a hydraulic pump to fill the liquid until the pressure increase detected by the pressure sensor 33 exceeds the set threshold, and then closes the solenoid valve, and opens the heating coils in sequence from the top to the bottom of the pressure head 20, so that the adhesive layer 11 expands in sequence from the bottom to the top and presses the barrier layer 12 and the printing layer 13, and then closes the heating coils, and the pressure head driving mechanism drives the pressure head 20 to withdraw from the mold to complete the production of the in-mold label. The prefabricated shape allows a gap between the adhesive layer 11, the barrier layer 12 and the printing layer 13. When the top of the pressure head 20 passes through the adhesive layer 11, the barrier layer 12 and the printing layer 13 and presses against the bottom of the mold cavity 31, the bottoms of the adhesive layer 11, the barrier layer 12 and the printing layer 13 are tightly attached, and there is a gap on the side, so that the heating coil is turned on in sequence from the top to the bottom of the pressure head 20, so that the part of the adhesive layer 11 close to the bottom first expands and presses the barrier layer 12 and the printing layer 13, so that the small amount of air remaining on the side can be gradually squeezed out, so that the adhesive layer 11, the barrier layer 12 and the printing layer 13 are tightly attached. The rest of the structure is the same as that of the first embodiment.

[0025] The new technical effect of this embodiment compared to the first embodiment is that the production equipment provided by the present invention makes the produced in-mold label adhesive layer 11, barrier layer 12 and printing layer 13 closely fit each other without air residue, thereby improving the aesthetics of the label.

[0026] The above-described embodiment is only a preferred solution of the present invention and does not limit the present invention in any form. There are other variations and modifications without exceeding the technical solution described in the claims.

Claims

1. A device for producing preformed in-mold labels, characterized in that: It includes a preforming device and a laminating device, wherein the preforming device respectively forms the bonding layer, the barrier layer and the printing layer into preformed shapes, wherein the preformed shapes allow the bonding layer, the barrier layer and the printing layer to have gaps, wherein the laminating device includes a machine base, a pressing head, a plurality of heating coils, a pressing head driving mechanism and a reverse mold, wherein the outer wall of the pressing head is in contact with the inner wall of the bonding layer, an air hole is provided on the top of the pressing head, the inner wall of the reverse mold is in contact with the outer wall of the printing layer, the reverse mold is mounted on the machine base, the pressing head driving mechanism is mounted on the machine base, the pressing head is connected to the pressing head driving mechanism, and a plurality of the heating coils are sequentially arranged in the pressing head; It also includes a hydraulic pump, a liquid tank, a liquid supply pipe, a solenoid valve and a controller. The inverted mold includes a mold body, a liquid leakage hole, a liquid cavity, a liquid supply port, an air outlet, an air valve and a pressure sensor. The front part of the mold body has a mold cavity, the rear part of the mold body has a hollow liquid cavity, the inner wall of the mold cavity is in contact with the outer wall of the barrier layer or the printing layer, the bottom of the mold cavity is provided with a plurality of liquid leakage holes, the liquid leakage holes connect the mold cavity and the liquid cavity, the pressure sensor is installed on the mold body to detect the liquid pressure in the liquid cavity, the rear part of the mold body is provided with a liquid supply port, the liquid supply port connects the liquid supply pipe and the liquid cavity, the liquid supply pipe is connected to the hydraulic pump through the solenoid valve, the hydraulic pump is connected to the liquid tank, and the solenoid valve and the pressure sensor are both connected to the controller; The adhesive layer is put into the pressure head, and then the barrier layer is put into the adhesive layer, the mold cavity is placed vertically, the mold cavity is pre-filled with liquid, and when the printing layer is gradually put into the mold cavity, the controller controls the air valve to open, and the controller controls the solenoid valve to open a first opening, push the printing layer to make the liquid flow into the liquid tank through the liquid supply pipe, when the printing layer is completely put into the mold cavity, the controller controls the air valve to close, and after the controller turns on the hydraulic pump to extract part of the liquid, the inverted mold is placed horizontally, and the pressure head driving mechanism drives the pressure head to push the adhesive layer and the barrier layer into the printing layer, and makes the top of the pressure head pass through the adhesive layer, the barrier layer and the printing layer to press against the bottom of the mold cavity, and use the hydraulic pump to fill the liquid until the pressure increase detected by the pressure sensor exceeds the set threshold, close the solenoid valve, and turn on the heating coils in sequence from the top to the bottom of the pressure head, so that the adhesive layer expands in sequence from the bottom to the top to press the barrier layer and the printing layer, then turn off the heating coil, and the pressure head driving mechanism drives the pressure head to withdraw the mold, and the production of the in-mold label is completed.

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