A soft package provided with a label chip

Abstract

The present invention relates to a flexible package provided with a label chip, wherein the flexible package comprises at least a heat-sealing layer and a barrier layer from the inside to the outside, wherein the barrier layer is the outermost layer of the flexible package, the barrier layer and the heat-sealing layer are stacked and connected, and the label chip is arranged between the barrier layer and the heat-sealing layer. The thickness of the barrier layer is 40-80 μm, and the thickness of the heat-sealing layer is not less than 30 μm. The average pore size of the barrier layer is 30-40 nm. The porosity of the barrier layer is 55-60%. The components for preparing the heat-sealing layer include ethylene-propylene copolymer, high-density polyethylene, and polyacrylate. The components for preparing the barrier layer include high-density polyethylene, poly(propylene-alt-ethylene), poly(butyl acrylate-styrene), and ultra-high molecular weight polyethylene. The tensile strength of the barrier layer and the heat-sealing layer are both 100 kgf / cm 2 The puncture strength of the barrier layer and the heat seal layer is 3.0N or more.

Description

Technical Field

[0001] The present invention relates to the field of soft packaging, in particular to a soft packaging provided with a label chip. Background Art

[0002] Ultra-high frequency radio frequency identification (RFID) technology is a contactless automatic identification technology. In the RFID system, the reader sends a radio frequency microwave signal to activate the RFID tag chip and receives the RFID signal returned from the tag to achieve the purpose of identification. The tag chip can be attached to various items. At present, ultra-high frequency RFID has been applied to various fields, such as wine anti-counterfeiting, clothing, electricity, etc.

[0003] The tag chip generally includes an RFID chip and an antenna assembly electrically connected to the RFID chip, the RFID chip contains data (such as an identification code of a product type and / or a product component), and the antenna assembly is used to transmit signals to a reader and / or receive signals from a reader.

[0004] At present, ultra-high frequency radio frequency identification (RFID) technology is widely used in the field of rigid packaging. For example, a tag chip is set on a rigid packaging container for packaging high-end products (such as alcohol, medicine, etc.). The data stored in the tag chip on the rigid packaging container can be read by a reader / writer, so that the information of the product inside the rigid packaging container (such as brand, production date, production address, etc.) can be identified without touching the rigid packaging container.

[0005] At present, the technical problems in applying ultra-high frequency radio frequency identification (RFID) technology in the field of flexible packaging are as follows: 1. When the tag chip is attached to the outside of the flexible packaging by adhesive, the tag chip is easy to be lost during the transportation of the flexible packaging container, and there is a possibility of artificial removal of the label; 2. Embedding the tag chip into the composite film of the flexible packaging can eliminate the risk of the tag chip being lost during the transfer and transportation of goods, but due to the electromagnetic wave reflection on the interface of different film layers of the composite film of the flexible packaging container, the electromagnetic wave energy absorption of the composite film, the interference and diffraction of the composite film to the electromagnetic wave, etc., the signal strength of the tag chip will be weakened, resulting in a significant decrease in the recognition performance and recognition rate of the tag chip. Summary of the invention

[0006] In view of the technical problems existing in the prior art, the present invention provides a flexible package provided with a label chip, wherein the label chip is embedded in a composite film of the flexible package container, and the recognition performance and recognition rate of the label chip will not be significantly reduced.

[0007] The tag chip described in the present invention includes an RFID chip that electronically communicates with one or more dipole-type antennas. The antenna component of the tag chip takes the form of a hybrid ring slot antenna or a slot ring hybrid antenna. The tag chip also includes an integrated circuit, and the RFID chip and the antenna component are both arranged on the integrated circuit.

[0008] The flexible package described in the present invention is a roll film or a packaging bag prepared from a composite film.

[0009] The flexible package described in the present invention includes at least a heat-sealing layer and a barrier layer from the inside to the outside, wherein the barrier layer is the outermost layer of the flexible package, the barrier layer and the heat-sealing layer are stacked and connected, and both the barrier layer and the heat-sealing layer are made of polyolefin materials. The barrier layer is used as a surface layer, and its function is to provide barrier properties, surface puncture resistance and tear resistance. The function of the heat-sealing layer is to provide a heat-sealing surface, and the two layers of heat-sealing surfaces can be attached to achieve heat-sealing connection or heat-sealing bag making.

[0010] The present invention provides a flexible package provided with a label chip, wherein the label chip is provided between a barrier layer and a heat-sealing layer. By embedding the label chip between the barrier layer and the heat-sealing layer of the flexible package, the label chip is not easily separated from the flexible package, and the flexible package can realize functions such as anti-counterfeiting, traceability, and big data analysis by providing the label chip.

[0011] In one embodiment, both sides of the label chip are coated with a functional adhesive, the barrier layer covers one side of the label chip, and the heat seal layer covers the other side of the label chip. The functional adhesive is one or more of polyvinyl alcohol compound glue, polyurethane two-component glue and modified polyolefin adhesive. The part where the barrier layer and the heat seal layer are in direct contact is connected by thermal bonding.

[0012] The wireless signal of the antenna component of the tag chip is sent in the form of waves. Therefore, in order to prevent the tag chip embedded between the barrier layer and the heat-sealing layer of the flexible package from experiencing a significant decrease in recognition performance and recognition rate, the barrier layer and the heat-sealing layer must at least meet the following requirements:

[0013] 1. Since the antenna component of the tag chip is made of metal, the puncture strength of the barrier layer and the heat seal layer must be high enough to prevent damage by the tag chip;

[0014] 2. The thickness of the barrier layer should be as thin as possible while maintaining a certain mechanical strength, and the barrier layer cannot be doped with metal ions or provided with a metal layer. A soft package is provided with a tag chip, and the tag chip supports short-range wireless communication. A non-contact type of communication between the tag chip and the reader generally occurs within about 10 cm. In the case where the tag chip is embedded between the barrier layer and the barrier layer of the soft package, if the barrier layer is doped with metal ions or provided with a metal layer, due to the conductivity of the metal ions / metal layer, the wireless signal generated by the antenna component of the tag chip cannot penetrate the barrier layer doped with metal ions or provided with a metal layer and travel outward. Therefore, if the barrier layer is doped with metal ions or provided with a metal layer, the effect of the antenna component of the tag chip may be deteriorated;

[0015] 3. The barrier layer is provided with holes while maintaining a certain barrier performance. The width of the holes can be relatively small. The diffraction of the wavelength will allow the antenna component of the tag chip to send the wireless signal through the holes with a sufficient wavelength. Preferably, the width of the hole is not greater than 1 / 2 of the wavelength of the wireless signal generated and / or received by the antenna component of the tag chip;

[0016] 4. The angle range in which the reader can identify the tag chip needs to be as wide as possible. Therefore, the porosity of the barrier layer should be within a certain range while maintaining a certain tear resistance.

[0017] The barrier layer may be a single-layer or multi-layer polyolefin porous film, such as a single-layer polyethylene porous film, a multi-layer polyethylene porous film, a single-layer polypropylene porous film, a multi-layer polypropylene porous film, a polyethylene / polypropylene composite multi-layer film (such as polyethylene / polypropylene composite film, polyethylene / polypropylene / polyethylene composite film, polypropylene / polyethylene / polypropylene composite film), etc. However, in order to make the thickness of the barrier layer as thin as possible, preferably, the barrier layer is a single-layer polyolefin porous film.

[0018] If the hole width and / or porosity of the barrier layer are too large, it will have a negative effect on the barrier performance and mechanical strength of the barrier layer. The barrier layer and the heat seal layer can both be doped with insulating materials to enhance the mechanical strength of the barrier layer. By controlling the width range and porosity range of the holes on the barrier layer, the uniformity of the magnetic field line distribution in the area surrounded by the antenna assembly of the tag chip can be improved, thereby improving the performance of the antenna assembly of the tag chip.

[0019] In the present invention, the inventor unexpectedly discovered through multiple experiments that when the following conditions are met at the same time:

[0020] 1. The thickness of the barrier layer is 40-80μm, and the thickness of the heat sealing layer is not less than 30μm;

[0021] 2. The average pore size of the barrier layer is 30-40nm;

[0022] 3. The porosity of the barrier layer is 55-60%;

[0023] 4. The components for preparing the heat seal layer include ethylene-propylene copolymer, high-density polyethylene, and polyacrylate;

[0024] 5. The components for preparing the barrier layer include high-density polyethylene, poly(propylene-alt-ethylene), poly(butyl acrylate-styrene), and ultra-high molecular weight polyethylene;

[0025] 6. The tensile strength of the barrier layer and the heat seal layer shall not be less than 100kgf / cm 2 ;

[0026] 7. The puncture strength of the barrier layer and the heat seal layer shall not be less than 3.0N;

[0027] At this time, the barrier layer and the heat-sealing layer have good mechanical strength, which prevents damage by the label chip embedded between the barrier layer and the heat-sealing layer, so that the flexible package provided with the label chip is not easily damaged during storage and transportation. The barrier layer will not cause a significant decrease in the recognition performance and recognition rate of the label chip while providing good barrier performance.

[0028] The following describes the invention in conjunction with specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The accompanying drawings further illustrate the present invention, but the embodiments in the accompanying drawings do not constitute any limitation to the present invention.

[0030] Figure 1 It is a structural diagram of a tag chip provided by an embodiment of the present invention.

[0031] Figure 2 It is a cross-sectional view of an antenna assembly of a barrier layer and a tag chip provided in one embodiment of the present invention.

[0032] The reference numerals are: 1. antenna; 2. RFID chip; 3. barrier layer; 31. hole. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] Unless otherwise specified, the raw materials and reagents used in the following examples are commercially available or can be prepared by known methods.

[0035] The average pore size involved in the following embodiments is tested by a PMI pore size analyzer according to the capillary flow method. The specific steps are: a barrier layer that is completely saturated with an infiltration liquid is placed in a closed sample chamber of a certain volume. Under a series of pressures, the gas overcomes the capillary action of the liquid in the pores and discharges the infiltration liquid in the pores until the pores are emptied. The gas pressure and flow rate are recorded, and then the pore size and distribution are calculated according to the corresponding formula.

[0036] The tensile strength in the following examples is measured in accordance with GB / T1040.1-2006 standard using a 25 mm wide strip barrier layer / heat sealing layer sample and a CMT4000 electronic testing machine from MTS.

[0037] The porosity in the following examples is based on the density of the test barrier layer (g / cm 3 ) = diaphragm weight / (thickness * area), and the theoretical value is 0.94g / cm 3 The porosity of the barrier layer is obtained by dividing the porosity of the barrier layer by the value of

[0038] The puncture strength in the following example is tested according to the test method in GB / T 36363-2018 using a CMT4000 electronic testing machine of MTS, and the maximum load is measured when a needle with a spherical front end (radius of curvature R: 0.5 mm) and a diameter of 1 mm is pierced into the barrier layer / heat sealing layer sample at a speed of 2 mm / s.

[0039] In the embodiment of the present invention, the heat sealing layer is a single-layer polyolefin film, and the heat sealing layer is prepared by a melt stretching method, and the specific steps are as follows:

[0040] S1. Extrusion casting: The components for preparing the heat seal layer are mixed and then extruded and cast to obtain a cast film;

[0041] S2. Annealing: subjecting the cast film to a high temperature annealing treatment to perfect the lamellae to obtain an annealed film;

[0042] S3. Stretching: cold drawing and hot drawing the annealed film to obtain a stretched film;

[0043] S4. Heat setting: heat setting the stretched film to obtain the heat sealing layer.

[0044] In the embodiment of the present invention, the barrier layer is prepared by a phase separation method, and the specific steps are as follows:

[0045] S1. Melt mixing: mixing the components of the barrier layer with the high boiling point pore former, heating, melt mixing, and obtaining a mixed melt;

[0046] S2. tableting: the mixed melt is tableted at high temperature to obtain a film;

[0047] S3 stretching: the membrane is cooled and then the pore-forming agent is removed, and biaxial stretching is performed to obtain a stretched porous membrane;

[0048] S4. Heat setting: heat setting the stretched porous film to obtain the barrier layer.

[0049] Example 1

[0050] An embodiment of the present invention provides a flexible package provided with a label chip. The flexible package has excellent flexibility relative to a rigid packaging container. The composite film layer of the flexible package includes a base layer, a printing layer, a heat sealing layer, and a barrier layer from the inside to the outside, wherein the base layer, the heat sealing layer, and the barrier layer 3 are all made of polyolefin materials, and the composite film layers are connected by heat sealing to obtain a sealed flexible package, and the label chip is arranged between the heat sealing layer and the barrier layer 3.

[0051] See also Figure 1 , Figure 1 is a structural diagram of a tag chip provided by an embodiment of the present invention, such as Figure 1 As shown, the tag chip includes: an antenna 1 and an RFID chip 2. The first end of the antenna 1 is connected to the first end of the RFID chip 2, and the second end of the antenna 1 is connected to the second end of the RFID chip 2. The antenna 1 includes a metal wire structure, and the metal wire is wound as follows Figure 1 The “U”-shaped structure shown can shorten the length of the antenna 1 in the soft package.

[0052] See also Figure 2 , Figure 2 2 is a cross-sectional view showing the barrier layer 3 and the antenna 1. The barrier layer 3 is provided with holes 31, and the average pore size range of the holes 31 is controlled so that the signal of the antenna 1 of the tag chip passes through the holes 31.

[0053] In the embodiment of the present invention, the components for preparing the heat seal layer include: 30-40 parts by mass of ethylene-propylene copolymer, 20-30 parts by mass of high-density polyethylene, 20-30 parts by mass of polyacrylate, 1-5 parts by mass of 1-butene, and 1-2 parts by mass of dioctyl terephthalate. The thickness of the heat seal layer is 30 μm, and the puncture strength of the heat seal layer is 3.5N. The average tensile strength at break of the heat seal layer is above 140 MPa, and the average tensile elongation at break is above 90%. The average tensile strength at break is the average of the tensile strength at break in the MD direction, i.e., the machine direction, and the tensile strength at break in the TD direction, i.e., the width direction, and the average tensile elongation at break is the average of the tensile elongation at break in the MD direction and the tensile elongation at break in the TD direction.

[0054] In the embodiment of the present invention, the porosity of the barrier layer is preferably 55% or more, which is preferred from the perspective of wireless signal transmission performance. As the upper limit of the porosity, it is preferably 60% or less from the perspective of ensuring mechanical strength. The porosity of the barrier layer can be adjusted by the component ratio, stretching temperature, and heat treatment conditions.

[0055] In the embodiment of the present invention, the average pore size of the barrier layer is preferably greater than 30 nm, and the upper limit is preferably less than 40 nm, and more preferably less than 35 nm. The average pore size of the barrier layer can be adjusted by component ratio, melt mixing, stretching ratio, and stretching method.

[0056] In an embodiment of the present invention, the upper limit of the film thickness of the barrier layer is preferably 80 μm or less, more preferably 70 μm or less, and further preferably 60 μm or less. The lower limit of the film thickness is 40 μm or more, more preferably 50 μm or more. By making the film thickness of the barrier layer less than 80 μm, the transmittance of the wireless signal can be improved. When the film thickness is less than 40 μm, the strength becomes low, the film is prone to cracking, or the resistance to foreign matter such as the antenna 1 becomes weaker, so it is not preferred. In addition, when the film is thicker, the effect of the antenna component of the tag chip may be deteriorated. The film thickness of the barrier layer can be adjusted by the width of the unstretched sheet, the film making speed, and the stretching ratio during stretching.

[0057] In the embodiment of the present invention, the components for preparing the barrier layer include: 40-50 parts by weight of high-density polyethylene, 20-30 parts by weight of poly(propylene-alt-ethylene), 20-30 parts by weight of poly(butyl acrylate-styrene), and 30-40 parts by weight of ultra-high molecular weight polyethylene.

[0058] Among them, ultra-high molecular weight polyethylene refers to ultra-high molecular weight polyethylene with a weight average molecular weight of 1.0×106 or more. High-density polyethylene refers to polyethylene with a density greater than 0.94g / cm 3 In addition, the barrier layer may contain various additives such as antioxidants, ultraviolet absorbers, pigments, dyes, etc. as needed within the range that does not impair the purpose of the present invention.

[0059] By controlling the component ratio of the barrier layer, the number and entanglement of the connecting molecular chains between the barrier layers can be controlled, and the connecting molecules can be highly oriented by stretching, thereby improving the mechanical strength of the barrier layer, such as puncture strength and tensile strength, without increasing the thickness.

[0060] Example 2 and Comparative Examples 1-3 all provide barrier layers of the same thickness (50 μm). The barrier layers are prepared using the same preparation process. The composition ratio of the barrier layers is shown in Table 1.

[0061] Table 1

[0062]

[0063] The porosity, tensile strength, puncture strength and average pore size of the barrier layers provided in Example 2 and Comparative Examples 1-3 were tested. The results are shown in Table 2.

[0064] Table 2

[0065] project Example 2 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Porosity (%) 58 45 52 50 50 <![CDATA[Tensile strength (kgf / cm 2 )]]> ≥200 160 180 180 120 Puncture strength (N) 5.5 4 3.2 3.5 4 Average pore size (nm) 32 40 35 40 35

[0066] According to the test results in Table 2, it can be judged that when any component of the barrier layer is missing, it will have a negative impact on the puncture strength and tensile strength of the barrier layer. The barrier layer provided in Example 2 has a small average pore size, a large porosity, good permeability to wireless signals, and can achieve barrier properties against microorganisms and dust. The excellent mechanical properties of the barrier layer can prevent the bag from being damaged.

[0067] It should be understood that the present invention provides a flexible package provided with a tag chip, and the tag chip is strategically designed to be covered by a heat seal layer and a barrier layer, ranging from, for example, simple point coverage to full coverage of the tag chip or partial coverage thereof, to achieve the desired results of various possible tag chip embedded in the flexible package design, configuration and structure. For example, the strategic design will vary between various radio frequency (RF) frequencies of UHF, HF or NFC. Moreover, the thickness of the heat seal layer and the barrier layer can vary according to the details of the tag chip and the intended application.

[0068] Without departing from the scope of the present disclosure, other embodiments may be employed in addition to those shown herein. For example, other means for attaching the tag chip to clothing or other fabric items or other flexible materials may be employed, such as sewing, pinning, or other connecting mechanisms. Further, tag chip construction variations may be employed. The relative sizes of the layers may vary depending on the intended use, including variations in the area of ​​the face sheet to fully extend beyond the internal components, and variations in the application area of ​​the functional or laminating adhesive to secure multiple components together.

[0069] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0070] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A flexible package provided with a label chip, characterized in that: The flexible package comprises at least a heat-sealing layer and a barrier layer from the inside to the outside, the barrier layer is the outermost layer of the flexible package, the barrier layer and the heat-sealing layer are stacked and connected, and the label chip is arranged between the barrier layer and the heat-sealing layer; The thickness of the barrier layer is 40-80 μm, and the thickness of the heat-sealing layer is not less than 30 μm; The average pore size of the barrier layer is 30-40 nm; The porosity of the barrier layer is 55-60%; The components for preparing the heat seal layer include 30-40 parts by mass of ethylene-propylene copolymer, 20-30 parts by mass of high-density polyethylene, 20-30 parts by mass of polyacrylate, 1-5 parts by mass of 1-butene, and 1-2 parts by mass of dioctyl terephthalate; The components for preparing the barrier layer include 40-50 parts by mass of high-density polyethylene, 20-30 parts by mass of poly(propylene-alt-ethylene), 20-30 parts by mass of poly(butyl acrylate-styrene), and 30-40 parts by mass of ultra-high molecular weight polyethylene; The ultra-high molecular weight polyethylene has a weight average molecular weight of 1.0×10 6 The ultra-high molecular weight polyethylene mentioned above, the high-density polyethylene refers to a polyethylene with a density greater than 0.94 g / cm 3 of polyethylene; The tensile strength of the barrier layer and the heat seal layer is not less than 100 kgf / cm 2 ; The puncture strength of the barrier layer and the heat-sealing layer is not less than 3.0N; Functional adhesives are coated on both sides of the label chip, the barrier layer covers one side of the label chip, and the heat sealing layer covers the other side of the label chip. The portions of the barrier layer and the heat sealing layer that are in direct contact are connected by thermal bonding, and the functional adhesive is one or more of polyvinyl alcohol compound glue, polyurethane two-component glue and modified polyolefin adhesive.

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