KR101518777B1

KR101518777B1 - Loop antenna printed by electric conductive ink and manufacturing method thereof

Info

Publication number: KR101518777B1
Application number: KR1020140013785A
Authority: KR
Inventors: 정진용; 조영일
Original assignee: 주식회사 스마테크
Priority date: 2014-02-06
Filing date: 2014-02-06
Publication date: 2015-05-11

Abstract

The present invention relates to a loop antenna printed with a conductive ink for an RFID system and a manufacturing method thereof, the loop antenna manufactured by printing a pattern on one side of a base film with a conductive ink, plasticizing and peeling off the pattern. The a loop antenna printed with a conductive ink according to the present invention comprises: a glass or ceramic plate (30); a loop circuit (33) formed on one side of the glass or ceramic plate (30) with a conductive ink which contains silver (Ag) and comes in the electrically conductive paste form; a first terminal (31) connected to the loop circuit (33) and formed on one side of the glass or ceramic plate (30) with the conductive ink which contains silver (Ag) and comes in the electrically conductive paste form; and a second terminal (32) separated from the loop circuit (33) and formed on one side of the glass or ceramic plate (30) with the conductive ink which contains silver (Ag) and comes the in electrically conductive paste form. The loop circuit (33) and the first and second terminals (31, 32) formed with the conductive ink are plasticized in a plasticization furnace at 100 to 700°C for eight to eleven minutes, which includes the following steps: a first heat treatment step of preheating at 100 to 500°C for two to three minutes, a second heat treatment step of heating at 500 to 700°C for four to five minutes, a third heat treatment step of cooling at 500 to 100°C, and a step of cooling at room temperature.

Description

TECHNICAL FIELD [0001] The present invention relates to a loop antenna printed with a conductive ink, and a method of manufacturing the same.

The present invention relates to a loop antenna printed with a conductive ink and a method of manufacturing the same. More particularly, the present invention relates to a loop antenna used in an RFID system, which is printed with conductive ink on one side of a base film, The present invention relates to a loop antenna printed with a conductive ink and a method of manufacturing the same.

Generally, a loop antenna is a receiving antenna and includes a wire wound in a loop shape. Such a loop antenna has an eight-character sensitive receiving area parallel to the surface of the loop.

Recently, development of M-commerce (mobile commerce) for mobile commerce using mobile terminals has been focused on, and development of RFID antennas, RFID readers, RFID tags, It is also attracting attention.

RFID (Radio Frequency Identification) is a wireless recognition device developed as a data input device as one of automatic recognition technologies. RFID can read, manage, and track animals, objects, people, etc. tagged with a reader and an antenna by storing the ID of the object to be recognized in a tag. This RFID technology has the advantage of simultaneously reading, modifying and updating several information, so it can solve the various problems that barcode technology does not overcome or actively cope with it, so that explosive demand will increase in future in logistics and security fields do.

This RFID antenna is implemented as a loop antenna. The near field communication (NFC) loop antenna for electronic payment is an antenna of 13.56 MHz band and is distinguished from a voice communication or a DMB (Digital Multimedia Broadcasting) antenna.

The mobile terminal for M-commerce is equipped with an RFID reader capable of reading the information recorded in the RFID tag. When an RFID tag (passive tag) storing a unique ID and data enters the magnetic field while radiating a radio wave from the antenna of the RFID reader, the RFID tag is activated and transmits its own ID and Data to the RFID reader . The RFID reader processes the transmitted ID and data to provide necessary services.

[0007] In a mobile phone equipped with an RFID reader, an electronic chip for processing ID and Data transmitted from an RFID tag is installed in the main body, and the antenna is detachably mounted on the main body Respectively. The antenna can be made in various sizes and shapes, and the resistance value and the inductance value are determined according to the thickness of the copper wire, the number of turns, and the diameter of the antenna.

1 shows a general structure of a loop antenna used for RFID. 1, the loop antenna 10 generally includes a loop pattern 11, a first lead portion 12 extending from one end of the loop pattern 11, and a second lead portion 12 extending from the other end of the loop pattern 11 A second lead portion 13 and external connection terminals 14 and 15 for providing contact with an external integrated circuit such as a tag. Since the loop antenna must form at least one turn, the second lead portion 13 is interlayer-wired so as to be twisted at least once with the loop pattern 11.

Conventionally, a method of etching a copper foil laminated on a thin film substrate or forming a loop pattern by ultrasonic welding is used in order to reduce the volume occupied by an antenna in mounting a loop antenna to a mobile terminal.

A conventional method of etching a double-sided copper foil board to form a loop antenna is performed as follows. The loop pattern 11, the first lead portion 12 and the first external connection terminal 14 are formed on one side (for example, the surface) of the double-sided copper-clad substrate and the other side The second lead portion 13 and the second external connection terminal 15 are formed. The loop pattern 11 and the second lead portion 13 are formed for interlayer connection so that the loop pattern 11 on the front surface and the second lead portion 13 on the back surface are connected to each other with the substrate layer interposed therebetween. A through hole 16 is formed in the contact portion to which the connection is made.

According to the conventional method of manufacturing the loop antenna by the copper foil etching, the loop pattern 11 is formed by etching the copper foil pattern to form the loop pattern 11, the second lead portion 13 and the like, And the second lead portions 13 must be connected to each other.

In order to form the loop pattern 11, the lead portions 12 and 13 and the external connection terminals 14 and 15, the surface and the back surface of the double-sided copper foil board are etched, and the formation of the through holes 16 A complicated process such as etching treatment, electroless plating for forming a seed layer, and electrolytic plating for forming an electrically conductive layer are carried out, and it is possible to use a plating solution containing a toxic substance There is a problem that the risk of environmental pollution is large and the waste water treatment cost is excessively generated.

In addition, since a part of the double-sided copper foil pattern is removed and discarded by etching, the utilization efficiency of the material is low and the base film is limited to an ultra-high-priced polyimide film (PI film).

Meanwhile, a conventional method of manufacturing a loop antenna using ultrasonic welding is as follows. Flexible materials such as plastic films (PVC), polyester films (PET), and ABS (Acrylonitrile Butadiene Styrene) films have properties in which plastic deformation starts at 80 DEG C or below by ultrasonic vibration.

A loop pattern is formed by using an insulated copper wire on the soft material and the copper wire patterned by ultrasonic welding is fused to the soft material.

The loop antenna manufacturing method using ultrasonic welding is environmentally safe compared with the method using copper foil etching, but it is difficult to freely design circuit elements because it is not suitable for mass production and uses standardized copper wire because the loop pattern must be patterned one by one. . For example, it is very difficult to design any part of the loop pattern to have a different width than the other parts.

To solve these problems, Korean Patent No. 10-1301199 is proposed.

The prior art discloses a loop antenna 20 having a first metal pattern 21 on its surface and a second metal pattern 22 on its rear surface and connected to the first metal pattern 21, A through hole (23) is prepared at a position where the first metal pattern (21) and the second metal pattern (22) are to be connected. The first metal pattern (21) An intermediate film (24) on which a pattern (22) is transferred to the back side; An upper cover film (25) for covering the surface of the intermediate film (24) and the first metal pattern (21); And a lower cover film 26 for covering the back surface of the intermediate film 24 and the second metal pattern 22. Since the metal pattern necessary for the loop antenna 20 is formed by electroplating, The effect of environmental pollution is less and the waste water treatment cost is reduced.

However, in the prior patent, it is necessary to manufacture a pre-plated frame in which a first metal pattern 21 and a second metal pattern 22 are formed on the front and back surfaces, and the first metal pattern 21 and the second metal pattern 22 And an upper cover film 25 for covering the surface of the intermediate film 24 and the first metal pattern 21. The intermediate film 24 has a through hole 23 at a position to which the first metal pattern 21 is to be connected, And a lower cover film 26 for covering the rear surface of the intermediate film 24 and the second metal pattern 22 should be prepared and the first metal pattern 21 should be provided on the rear surface of the intermediate film 24 The second metal pattern 22 should be transferred to the rear surface of the intermediate film 24 and the upper cover film 25 and the lower cover film 26 should be transferred to the intermediate film 24, And the first metal pattern 21 and the second metal pattern 21 are connected through the through holes 23 through the through holes 23 There is a problem that is a complex process that should be necessary.

Further, there is a problem that the surface resistance value is high and the antenna performance is deteriorated.

1. Korean Patent No. 10-1301199 entitled " Loop Antenna, Method for Manufacturing Loop Antenna and Method for Manufacturing RF ID Card "(Registered on Mar. 2013. 22.)

Accordingly, it is an object of the present invention to solve the above problems, and it is an object of the present invention to provide a method of manufacturing a loop antenna in which a plating frame is not required, And it is an object of the present invention to provide a loop antenna printed with a conductive ink having a simple production process, easy shape change of the loop circuit, and low surface resistance, thereby improving antenna performance, and a manufacturing method thereof.

The loop antenna printed with the conductive ink according to the present invention comprises a glass plate or a ceramic plate; A loop circuit formed of a conductive ink which is a conductive paste containing silver (Ag) on one side of the glass plate or ceramic plate; A first terminal formed of a conductive ink which is a conductive paste containing silver (Ag) on one side of the glass plate or the ceramic plate and connected to the loop circuit; And a second terminal formed of a conductive ink which is a conductive paste containing silver (Ag) on one side of the glass plate or the ceramic plate and separated from the loop circuit; The loop circuit 33 and the first and second terminals 31 and 32 formed of the conductive ink are fired at a temperature of 100 to 700 ° C. for 8 to 11 minutes in a firing furnace, Heated to 500 to 700 ° C for 4 to 5 minutes in the second heat treatment section, cooled to 500 to 100 ° C in the third heat treatment section, and then naturally cooled at room temperature.

In addition, a method of manufacturing a loop antenna printed with a conductive ink according to the present invention includes the steps of preparing a glass plate or a ceramic plate; Pattern printing the first and second terminals and the loop circuit with a conductive ink, which is a conductive paste containing silver (Ag), on one side of the glass plate or the ceramic plate; Firing the pattern printed first and second terminals and the loop circuit; Peeling the first and second fired terminals from the glass plate or the ceramic plate by covering the loop circuit with a transparent adhesive film having adhesion property; Attaching the peeled first and second terminals and the transparent adhesive film to which the loop circuit is attached to the ferrite sheet so that the peeled first and second terminals and the loop circuit are attached to the ferrite sheet; Forming an insulating film on the loop circuit to connect the inner end of the loop circuit to the second terminal; And connecting a connection circuit of a flexible printed circuit board (FPCB) between an inner end of the loop circuit and the second terminal.

As described above, the loop antenna printed with the conductive ink according to the present invention and its manufacturing method do not require a plating frame manufacturing process, and do not use any hazardous materials during the etching process and the etching process during the mass production process, There is an advantage to be able to.

In addition, by baking the loop circuit formed of the conductive ink and the first and second terminals, the conductive ink is densified and densified, so that there is an advantage that it is not broken in bending.

Further, by baking the loop circuit formed of the conductive ink and the first and second terminals, there is an advantage that the surface resistance value is lowered and the antenna performance is improved.

Further, the thickness of the loop antenna can be reduced, and the manufacturing method thereof is also simple and the manufacturing cost is reduced.

1 and 2 are general structural diagrams of a loop antenna used for a conventional RFID.
Figs. 3A to 3E are diagrams showing a manufacturing process of a loop antenna printed with a conductive ink according to the present invention. Fig.
4 is a flowchart showing a manufacturing process of a loop antenna printed with a conductive ink according to the present invention.
5 is a schematic view of a loop circuit portion of a loop antenna printed with a conductive ink according to the present invention.
6 is a schematic view of an FPCB terminal portion of a loop antenna printed with a conductive ink according to the present invention.

Hereinafter, a loop antenna printed with the conductive ink according to the present invention and a method of manufacturing the same will be described in detail with reference to the drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear. The following terms are defined in consideration of the functions of the present invention, and they may vary depending on the intentions or customs of the client, the operator, the user, and the like. Therefore, the definition should be based on the contents throughout this specification.

Like numbers refer to like elements throughout the drawings.

4 is a flowchart illustrating a manufacturing process of a loop antenna printed with a conductive ink according to an embodiment of the present invention, FIG. 5 is a flowchart illustrating a manufacturing process of a loop antenna according to the present invention FIG. 6 is a schematic view of an FPCB terminal portion of a loop antenna printed with a conductive ink according to the present invention. FIG. 6 is a schematic view of a loop circuit portion of a loop antenna printed with conductive ink according to the present invention.

3A to 3E, the manufacturing process of the loop antenna printed with the conductive ink according to the present invention is such that first and second terminals 31 and 32 are formed on one side of a glass or ceramic plate 30, And a loop circuit 33 are formed. Here, the first and second terminals 31 and 32 and the loop circuit 33 are printed on one side of the glass plate or the ceramic plate 30 using conductive ink, which is a conductive paste containing silver (Ag). The first and second terminals 31 and 32 are connected to an external device by soldering or a connector so that a radio wave signal received through the loop circuit 33 can be supplied to an external device.

Thereafter, the loop circuit 33 and the first and second terminals 31 and 32 formed of the conductive ink are fired under the firing conditions as described below.

Thereafter, a transparent adhesive film 35 having adhesiveness is overlaid on the first and second terminals 31 and 32 printed on the glass plate or the ceramic plate 30 and the loop circuit 33, 1 and the second terminals 31 and 32 and the loop circuit 33 are peeled from the glass plate or the ceramic plate 30.

Thereafter, the transparent adhesive film 35 to which the peeled first and second terminals 31 and 32 and the loop circuit 33 are attached is cut to a proper size to be described later, and a ferrite sheet So that the peeled first and second terminals 31 and 32 and the loop circuit 33 are attached to the ferrite sheet.

Thereafter, on the loop circuit 33 to connect the inner terminal 34 of the loop circuit 33 and the second terminal 32 which is not connected to the loop circuit 33, without being electrically short- The insulating film 36 is formed.

A connecting circuit 37 of a flexible printed circuit board (FPCB) is connected to the insulating film 36 to connect the inner terminal 34 of the loop circuit 33 and the second terminal 32. [ And electrically connects the inner terminal 34 and the second terminal 32 of the loop circuit 33. [

The loop circuit 33 and the first and second terminals 31 and 32 formed of the conductive ink are fired at a temperature of 100 to 700 ° C. for 8 to 11 minutes in a firing furnace. In the first heat treatment section, for 2 to 3 minutes at 100 to 500 ° C, for 4 to 5 minutes at 500 to 700 ° C in the second heat treatment section, at 500 to 100 ° C in the third heat treatment section After cooling, it is naturally cooled at room temperature.

Now, the flow of the manufacturing process of the loop antenna printed with the conductive ink according to the present invention will be described with reference to FIG.

First, a glass plate or a ceramic plate 30 is prepared (S410).

Then, the first and second terminals 31 and 32 and the loop circuit 33 are pattern-printed with a conductive ink, which is a conductive paste containing silver (Ag), on one side of the glass plate or the ceramic plate 30 ).

Thereafter, the pattern printed first and second terminals 31 and 32 and the loop circuit 33 are fired (S430).

Thereafter, a transparent adhesive film 35 having adhesiveness to the fired first and second terminals 31 and 32 and the loop circuit 33 is covered and separated from the glass plate or the ceramic plate 30 (S440) . The transparent adhesive film 35 serves to peel off the first and second terminals 31 and 32 and the loop circuit 33 from the glass plate or the ceramic plate 30.

Thereafter, the transparent adhesive film 35 to which the peeled first and second terminals 31 and 32 and the loop circuit 33 are attached is attached to the ferrite sheet cut to a predetermined size, 1 and the second terminals 31 and 32 and the loop circuit 33 are attached to the ferrite sheet (S450). Here, the transparent adhesive film 35 is peeled off after the peeled first and second terminals 31 and 32 and the loop circuit 33 are attached to the ferrite sheet. In addition, the ferrite sheet is lower in price than a PI (polyimide) film or a PE (polyethylene) film which is conventionally used as a base film.

Thereafter, on the loop circuit 33 for connecting the inner terminal 34 of the loop circuit 33 and the second terminal 32 which is not connected to the loop circuit 33 without being short- An insulating film 36 is formed (S460). Here, the insulating layer 36 may be formed by applying an insulating material, but it is more preferable to use a film-like thin plate made of an insulating material.

Thereafter, the inner terminal 34 of the loop circuit 33 is connected to the second terminal 32, and the connection circuit 37 of the flexible printed circuit board FPCB passes over the insulating film 36 The inner terminal 34 of the loop circuit 33 is electrically connected to the second terminal 32 (S470). Since the connection circuit 37 is connected to the inner terminal 34 and the second terminal 32 in a superposed manner, the inner terminal 34 and the second terminal 32 of the loop circuit 33 are mutually connected But is not connected to the loop circuit 33 between the inner terminal 34 and the second terminal 32 of the loop circuit 33 because it is connected to pass through the insulating film 36. The loop circuit 33 between the inner terminal 34 and the second terminal 32 of the loop circuit 33 and the connection circuit 37 passing over the loop circuit 33 are connected to each other It may be of such a size as not to conduct.

In step S430, the loop circuit 33 and the first and second terminals 31 and 32 formed of the conductive ink are fired at a temperature of 100 to 700 ° C. for 8 to 11 minutes in a firing furnace. Due to rapid temperature rise and fall, In order to prevent the ink from being damaged, the ink is preheated at 100 to 500 ° C for 2 to 3 minutes in the first heat treatment section, heated at 500 to 700 ° C for 4 to 5 minutes in the second heat treatment section, After cooling to 100 캜, it is naturally cooled at room temperature.

Now, a loop circuit portion of a loop antenna printed with the conductive ink according to the present invention will be described with reference to FIG.

The loop circuit portion of the loop antenna printed with the conductive ink according to the present invention comprises a glass plate or a ceramic plate 30 and a loop circuit formed of a conductive ink which is a conductive paste containing silver (Ag) And an inner terminal 34 of the loop circuit 33 and a first connection part 51 connected to the loop circuit 33 and connected to an antenna circuit part A first terminal 31 and a second terminal 32 separated from the loop circuit 33 and having a first contact part 53 at one end and a second connection part 52 connected to the antenna circuit part at the other end, .

The inner terminal 34 serves as a connecting part for connecting the loop circuit 33 and the second terminal 32.

The FPCB terminal portion of the loop antenna printed with the conductive ink according to the present invention will now be described with reference to FIG.

The FPCB terminal portion of the loop antenna printed with the conductive ink according to the present invention is a connection circuit 37 of a flexible printed circuit board (FPCB). One end of the connection circuit 37 is connected to a second end And a third contact part 62 connected to the second terminal 32 is formed at the other end of the connection circuit 37. [

The connection circuit 37 passes over the insulating film 36 and is connected to the inner end 34 of the loop circuit 33 as described above.

The first terminal 31 and the second terminal 32 of the loop antenna printed with the conductive ink according to the present invention constructed as described above are connected to and operated by the antenna circuit portion. Since the antenna circuit portion is well known in the art Is omitted.

As described above, the loop antenna printed with the conductive ink according to the present invention and the manufacturing method thereof do not require a plating frame manufacturing process and do not use any hazardous materials during the etching process and the etching process during the mass production process. . Further, when the conductive ink is fired, the conductive ink is concentrated and densified, so that the conductive ink is not broken in bending. Further, by firing the conductive ink, the surface resistance value is lowered, and the antenna performance is improved. Further, the thickness of the loop antenna can be reduced, and the manufacturing method thereof is also simple and the manufacturing cost is low.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, Various changes, modifications or adjustments to the example will be possible. Therefore, the scope of protection of the present invention should be construed as including all changes, modifications, and adjustments that fall within the spirit of the technical idea of the present invention.

30: glass plate or ceramic plate 31: first terminal
32: second terminal 33: loop circuit
34: Inner end 35: transparent adhesive film
36: insulating film 37: connection circuit

Claims

A glass plate or ceramic plate (30);
A loop circuit 33 formed of a conductive ink, which is a conductive paste containing silver (Ag), on one side of the glass plate or the ceramic plate 30;
A first terminal 31 formed of conductive ink which is a conductive paste containing silver (Ag) on one side of the glass plate or the ceramic plate 30 and connected to the loop circuit 33;
And a second terminal (32) formed of a conductive ink, which is a conductive paste containing silver (Ag), on one side of the glass plate or the ceramic plate (30) and separated from the loop circuit (33);
The loop circuit 33 and the first and second terminals 31 and 32 formed of the conductive ink are fired at a temperature of 100 to 700 ° C. for 8 to 11 minutes in a firing furnace, Heated at 500 to 700 ° C for 4 to 5 minutes in the second heat treatment section, cooled to 500 to 100 ° C in the third heat treatment section, and then cooled naturally at room temperature. antenna.

The method according to claim 1,
Wherein the loop circuit (33) and the second terminal (32) are connected by a connection circuit (37) of a flexible printed circuit board (FPCB).

delete

Preparing a glass plate or a ceramic plate 30 (S410);
A step S420 of pattern printing the first and second terminals 31 and 32 and the loop circuit 33 with a conductive ink which is a conductive paste containing silver (Ag) on one side of the glass plate or the ceramic plate 30, Wow;
(S430) baking the pattern printed first and second terminals (31, 32) and the loop circuit (33);
A step S440 of peeling off the transparent adhesive film 35 having adhesion to the fired first and second terminals 31 and 32 and the loop circuit 33 from the glass or ceramic plate 30 ;
The transparent adhesive film 35 attached with the peeled first and second terminals 31 and 32 and the loop circuit 33 is attached to the ferrite sheet so that the peeled first and second terminals 31 and 32 ) And a loop circuit (33) to the ferrite sheet (S450);
A step (S460) of forming an insulating film (36) on the loop circuit (33) to connect the inner terminal (34) of the loop circuit (33) and the second terminal (32);
(S470) connecting a connection circuit (37) of a flexible printed circuit board (FPCB) between an inner end (34) of the loop circuit (33) and a second terminal (32) Gt; a < / RTI > printed loop antenna.

The method of claim 4,
The transparent adhesive film 35 is peeled off after the peeled first and second terminals 31 and 32 and the loop circuit 33 are attached to the ferrite sheet in step S450. A method of manufacturing a loop antenna printed with ink.

The method of claim 4,
The loop circuit 33 and the first and second terminals 31 and 32 formed of the conductive ink are fired at a temperature of 100 to 700 ° C. for 8 to 11 minutes in a firing furnace, Heated at 500 to 700 ° C for 4 to 5 minutes in the second heat treatment section, cooled to 500 to 100 ° C in the third heat treatment section, and then cooled naturally at room temperature. A method for manufacturing an antenna.