KR100338523B1 - A cover tape for carrier tape - Google Patents

Abstract

The present invention relates to a transparent cover tape for a carrier tape used in small chip packaging. The present invention provides a carrier tape comprising a support on which a chip-shaped electronic component is mounted, a transparent cover tape covering an upper portion of the support, and a bottom tape of the support, wherein the transparent cover tape is an ethylene-based polymer selected from low density polyethylene and ethylene copolymer having a specific softening point. It is characterized by containing a resin as a base resin and rosin-based petroleum resin and a modified polyethylene resin substituted with lime in the rosin. According to the present invention, since the adhesive strength is enhanced by the use of rosin-based petroleum resin, it is easy to mount a small chip and exhibits excellent peelability not to be caused by biting the ground layer during peeling, and provides antistatic property without a separate conductive layer. By recycling the pulp of the cardboard, which is the material of the carrier tape, even if the physical properties of the ground layer is reduced, it can be easily used for packaging small chip parts.

Description

Transparent cover tape for carrier tape used for small chip packaging {A COVER TAPE FOR CARRIER TAPE}

The present invention relates to a transparent cover tape for a carrier tape used in small chip packaging.

In general, when assembling electronic components such as semiconductor chips, a method of surface mounting by simple manual operation is widely used.

However, in recent years, in order to improve the inconvenience of the surface mounting method by manual work and to ensure the speed of the work line, the packaging process is changing to an automated process. Accordingly, the development of the material of the carrier tape for small chip packaging used in the automated process is also parallel.

The carrier tape is composed of a ground layer serving as a support for mounting the chip-shaped electronic components so that the chip-shaped electronic components can be packaged without shaking, a transparent cover tape configured to cover the upper portion of the support, and a bottom tape covering the bottom of the support. have.

In addition, the ground layer serving as a support is formed with a hole for mounting a small chip-type electronic component, which is perforated to move automatically during transportation. Here, the transparent cover tape is composed of a sealant layer and a transparent film layer made of a general heat adhesive resin composition, and a conductive layer is included as necessary.

The process of packaging a small chip in an automated process using the carrier tape configured as described above will be described below.

First, heat-press the heat-adhesive tape on one side of the support, and then store the chip-shaped electronic component in an open hole on the other side, and heat and press another heat-adhesive tape thereon, whereby the cardboard carrier on which the chip-shaped electronic component is placed Is packaged to have a sandwich shape. Subsequently, in the surface mounting process for assembling electronic components, the heat-compressed tape layer is peeled off, and the exposed chip components are vacuum-sucked and mounted on a circuit board.

Such a carrier tape requires the following characteristics.

First, the transparent cover tape of the carrier tape is bonded to pack the chip parts and then peeled off for the surface mounting of the chip parts. However, if the thermal adhesive strength is too low, the area wound on the reel after packaging may be detached, whereas if the thermal adhesive strength is too high, a problem arises in that the layer is bited and separated when used in the mounting process, so that the thermal adhesive peel strength is 20 to 20. It is preferable to maintain at 60 g / mm and manufacture. In addition, it is important that the peeling of the cover tape from the cardboard carrier in which the chip is stored does not occur when peeling the cover tape from the cardboard carrier in which the chip is stored so as not to damage the chip.

Second, there should be an antistatic property for controlling the generation of static electricity generated by the interaction of the chip-shaped electronic component and the cover tape. If there is no antistatic property, there is a risk of damaging the electronics chip by popping out a small chip due to the repulsive force during the packaging process. Therefore, a surface specific resistance value of less than 10 ¹³ Ω / □ is required.

Third, the transparency of the tape is required to check the chip-type electronic components mounted for the packaging quality management, and particularly, the blocking resistance is required to smoothly unwind the tape wound on the reel. In addition, when the tape of the softening point or the adhesive layer has a sticky property, there may be a problem that the small chip component sticks to the tape.

Therefore, various methods have been developed as a means for satisfying the characteristics required for the heat-adhesive cover tape for the carrier tape. Among them, methods for improving the antistatic property and methods for improving thermal adhesiveness have been mainly studied by changing the composition of the sealant layer constituting the cover tape of the carrier tape.

As a method of improving the antistatic property, a method of incorporating an antistatic agent into the sealant layer (Japanese Utility Model Publication No. 63-149868, Japanese Patent Application Laid-open No. Hei 5-8339) is known, but the transparency of the carrier tape is known as this method. It is difficult to control damage and adhesive strength, and quality control is difficult.

In addition, a method of dispersing the conductive powder in an aqueous solution together with a water-soluble binder and applying it to a sealant layer is disclosed in Japanese Patent Application Laid-Open Nos. 4-367457 and 7-251860. In this method, coating and drying of an aqueous dispersion solution are known. Since the process must be added, the manufacturing cost is increased, which is uneconomical.

In addition, as a method of improving the heat adhesiveness of the carrier tape for changing the composition of the sealant layer, a high softening point tackifier is used to improve environmental resistance and to improve adhesiveness by using a sealant having a relatively high softening point and a low melting point. [Japanese Patent Laid-Open No. 60-105260].

In addition, a method of using an ethylene copolymer as an adhesive layer [JP-A-7-130899] and a method of applying the adhesive layer to an organic solution in which styrene butadiene and hydrogenated styrene butadiene-based rubber are dissolved [JP-A-4] 139287] and the like are known.

However, all of the above methods involve an increase in manufacturing cost and a cause of environmental problems.

In addition, there is a method of manufacturing a cover tape after corona treatment using a low density polyethylene and an ethylene copolymer in the sealant layer as in Korean Patent No. 0174328, but this method is used by recycling the pulp of the cardboard which is a material of the carrier tape As a result, the tearing strength of the strata becomes weak, but a problem occurs when the tape is thermally bonded and then peeled off, causing the strata to bite.

Accordingly, the present invention was devised to solve the problems caused by manufacturing cost increase caused by the conventional carrier tape and the problem of biting the ground layer when peeling off the transparent cover tape of the carrier tape as described above. Excellent Carrier Tape suitable for packaging small chips with excellent anti-blocking property that prevents the tape from being wound on the reel and prevents the antistatic property. The purpose is to provide a transparent cover tape.

In order to achieve the above object, the present invention provides a support tape on which a chip-shaped electronic component is mounted, a transparent cover tape configured to cover an upper portion of the support, and a carrier tape composed of a bottom tape of the support, wherein the transparent cover tape has a specific softening point. The low-density polyethylene and the ethylene copolymer having an ethylene-based resin, characterized in that the rosin-based petroleum resin, a modified polyethylene resin substituted with a lime (lime) to the rosin.

In addition, the present invention is a transparent cover tape for a carrier tape configured to cover the upper portion of the carrier tape, the transparent cover tape is an ethylene copolymer having a low density polyethylene and comonomer content of 0 to 30% by weight of 90 ~ 110 ℃ softening point Modified polyethylene grafted with 5 to 15 parts by weight of rosin-based petroleum resin in which rosin is substituted with a lime based on 100 parts by weight of the ethylene-based resin selected from among the base resins. It is produced by containing 1 to 5 parts by weight of resin.

According to the present invention, the tearing strength of the layer of the carrier tape is weakened by recycling the raw material of the cardboard, which is the material of the carrier tape, it is possible to prevent the phenomenon of biting the layer. That is, by using a rosin-based petroleum resin can have an antistatic property without forming a separate conductive layer, it is possible to provide a transparent cover tape that has excellent peeling property and does not bite the ground layer due to enhanced adhesion. .

1 is an exploded perspective view of a carrier tape according to the present invention.

Explanation of symbols on the main parts of the drawings

1: Support for mounting chip type electronic parts 2: Transparent cover tape

3: bottom tape 4: perforation for transportation

5: Hole for mounting chip type electronic parts

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

As shown in FIG. 1, a general carrier tape is composed of a support 1 on which a chip-shaped electronic component is mounted, a transparent cover tape 2 configured to cover an upper portion of the support, and a bottom tape 3 of the support. . Here, the transparent cover tape 2 is composed of a heat adhesive layer resin composition and a transparent film layer.

The transparent cover tape 2 should be manufactured to have a strong adhesive force when packaging a small chip, and to have an excellent peelability that does not occur when biting the ground layer during peeling.

Therefore, an ethylene-based resin selected from low-density polyethylene and an ethylene copolymer resin having a softening point of 90 to 110 ° C. is used as a base resin of the heat-adhesive layer resin composition of the transparent cover tape 2 to have an adhesive force with the support 1 layer.

In this case, the low-density polyethylene resin is to use not only the characteristics having the softening point, but also exhibits the characteristics of less neck in during extrusion coating. And, it is preferable to use the ethylene copolymer having a content of comonomer of 0 to 30% by weight. As the comonomer of the ethylene copolymer, one selected from vinyl acetate, acrylic acid, ethylene acrylate and methacrylate is used.

On the other hand, when only the resin selected from the low-density polyethylene and ethylene copolymer is used, since the problem of the rupture of the support remains, in the present invention, the resin having excellent chargeability as well as excellent peelability without rupturing the ground layer during the mounting process. A rosin petroleum resin is used in which rosin is substituted with a rosin to obtain a composition.

The rosin petroleum resin used in the present invention is a rosin petroleum resin having an acid value of 70 to 90 and a softening point of 100 to 115 ° C., which increases adhesion to a polyester film, which is a transparent thermoplastic film layer used in manufacturing a carrier tape. At the same time, it is not only to strengthen the adhesion to the strata, it is a major drug that can solve the problem caused by biting the strata especially when peeling can achieve the desired effect without adding a separate antistatic agent.

In the present invention, rosin-based petroleum resin is used in 5 to 15 parts by weight based on 100 parts by weight of the base resin. At this time, if the use content is set below the above range, the problem of rupture of the stratum arises, and if it is used in excess of the above range, the sticky property is generated and the blocking occurs, so it is necessary to use the appropriate amount with caution.

The present invention also uses 1 to 5 parts by weight of a modified polyethylene resin having a softening point of 90 to 110 ° C based on 100 parts by weight of the base resin to enhance the miscibility with the base resin and the rosin petroleum resin. As the modified polyethylene resin, maleic anhydride or fumaric acid is grafted. For example, 3% maleic anhydride may be grafted onto polyethylene resin using a twin screw extruder. At this time, if the use content of the modified polyethylene resin is out of the above range causes a problem that the ground layer rupture, pay attention to the advantage.

After applying the resin composition of the cover tape for a carrier tape composed of the above components to a transparent film, preferably a polyester transparent film with a thickness of 10 to 30㎛, after forming a cover tape, it is bonded to the ground layer of the support (1) and the bottom The carrier tape is manufactured by heating and pressing the tape 3.

When the carrier tape manufactured as described above is used in the automated process for packing small chip parts, the small chip is easily mounted by strengthening the adhesive strength of the rosin petroleum resin used as the resin composition of the cover tape, and the transparent cover tape of the carrier tape is chipped. When peeling off, the desired peel strength (20 to 60 gf / mm) can be obtained without rupture of the strata, and will not occur by biting the strata. It also has a surface intrinsic resistance of 10 ¹³ Ω / □.

As described above, by using the rosin-based petroleum resin substituted with the ethylene-based basic resin as the resin composition of the cover tape for a carrier tape according to the present invention, not only the adhesion to the ground layer was greatly enhanced by the characteristics of the rosin, In particular, it exhibits excellent peelability not to be caused by biting the strata and at the same time antistatic property, so it is effective for use in small chip capacitor and resistor manufacturers.

Examples 1-7 and Comparative Examples 1-22

Next, after obtaining a heat-adhesive resin using a Benbury mixer with the discharge temperature set to 150 ° C based on the composition and content as shown in Table 1, the coating layer was coated on a polyester film (SCA Co., Ltd., SP65) with a thickness of 25 μm. It was formed to prepare a transparent cover tape, and a carrier tape was prepared by a conventional method.

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1) Low Density Polyethylene: Samsung General Chemicals LDPE (MI 3, Density 0.920)

2) Ethylene Copolymer: Samsung General Chemicals EVA (MI 1.2, Density 0.938)

3) Petroleum resin: Acid value 70 ~ 90, Softening point 100 ~ 115 ℃, F-110 of Doi Chemical

4) Modified polyethylene: Self-manufactured by twin screw extruder (97 parts by weight of LDPE (MI 3, density 0.920), 3 parts by weight of maleic anhydride)

Classification (parts by weight) Low density polyethylene ¹⁾ Ethylene copolymer ²⁾ Petroleum Resin ³⁾ Modified polyethylene ⁴⁾ Example One 100 0 10 3 2 100 0 10 5 3 100 0 20 3 4 100 0 20 5 5 0 100 15 3 6 0 100 15 5 7 0 100 30 5 Comparative example One 100 0 0 0 2 0 100 0 0 3 100 0 One 0 4 100 0 5 0 5 100 0 10 0 6 100 0 15 0 7 100 0 20 0 8 100 0 10 One 9 100 0 10 6 10 100 0 20 One 11 100 0 20 6 12 100 0 20 7 13 0 100 One 0 14 0 100 5 0 15 0 100 10 0 16 0 100 20 0 17 0 100 30 0 18 0 100 15 9 19 0 100 15 10 20 0 100 30 7 21 0 100 30 10

Experimental Example: Measurement of Properties

The physical properties of the carrier tapes prepared in Examples 1 to 7 and Comparative Examples 1 to 22 were measured by the following method, and the results are shown in Table 2 below.

[Test Methods]

① Miscibility: Determined whether resin temperature rises up to set point temperature in Benbury mixer.

② Film formation degree: It is judged whether or not the resin flowing out of the extrusion coater maintains the film shape.

③ 180 ° peeling strength: Cut to 5.2mm width and thermo-compression bonding with 8mm wide cardboard carrier with Tokyo Wells TWA-6000 equipment (heating temperature 150 ℃, pressure 2 Kg / ㎠, speed 4 m / min.) After peeling at 23 ° C. for 24 hours, the peel strength was measured using a tensile strength meter (INSTRON, UTM) at 300 mm / min.

④ Strata rupture: Peel strength was measured and visually observed.

⑤ Environmental test: After packing the chip-type electronic parts, the change of transportation and storage process was aging test at constant temperature, and the adhesion between chip and tape was observed.

⑥ Blocking resistance: After manufacturing the cover tape, it was tested whether the blocking occurred due to the environmental change received during the storage and transportation in the rolled state, and thus the workability could be impaired because it was not freed in the establishment process.

⑦ Surface intrinsic resistance: measured after leaving at 50% relative humidity and 60 ℃ for 24 hours. The marking should be Ω / □.

division Miscibility Film Formation Peel Strength (gf / mm) Cardboard burst Environmental resistance Blocking resistance Surface specific resistance (10 ^x Example One Good Good 20 Good Good Good 12 2 Good Good 25 Good Good Good 12 3 Good Good 26 Good Good Good 11 4 Good Good 30 Good Good Good 11 5 Good Good 23 Good Good Good 12 6 Good Good 27 Good Good Good 12 7 Good Good 35 Good Good Good 11 Comparative example One Good Good - rupture - - 14 2 Good Good - rupture - - 14 3 Good Good - rupture - - 14 4 Good Good 10 Good Good Good 14 5 Good Good 12 Good Good Good 12 6 Good Good 14 Good Good Good 12 7 Good Bad - - - - - 8 Good Good 10 Good Good Good 12 9 Good Good - rupture - - 12 10 Bad - - - - - - 11 Good Good - rupture - - 11 12 Good Good - rupture - - 11 13 Good Good - rupture - - 14 14 Good Good - rupture - - 12 15 Good Good 15 Good Good Good 11 16 Bad - - - - - - 17 Bad - - - - - - 18 Good Good - rupture - - 12 19 Good Good - rupture - - 12 20 Good Good - rupture - - 11 21 Good Good - rupture - - 11

Note) 1. When tearing of cardboard occurs, it is not tearing strength of the layer rather than peeling strength, so it is not dataized.

2. The order in which data is measured from the left to the right in Table 2 in the order of manufacturing process. If the previous data is bad, it cannot be tested until the data is not made.

As described above, the transparent cover tape of the carrier tape of the present invention has an ethylene-based resin having a specific softening point as a base resin and contains a rosin-based petroleum resin and modified polyethylene to increase the adhesion to the ground layer due to the properties of the rosin. In addition, in particular, it is possible not only to prevent a phenomenon caused by biting the ground layer during peeling, but also to achieve the effect without prescribing a separate antistatic agent, which is suitable for manufacturing a carrier tape for packaging a semiconductor small chip.

Claims (1)

A transparent cover tape for a carrier tape configured to cover an upper portion of a carrier tape, The transparent cover tape is a low-density polyethylene at a softening point of 90 to 110 ℃ and an ethylene-based resin selected from the ethylene copolymer of 0 to 30% by weight of comonomer as a base resin, 5 to 15 parts by weight of rosin-based petroleum resin substituted with lime (lime) in rosin, 1 to 5 parts by weight of modified polyethylene resin grafted with maleic anhydride or fumaric acid, and organic compound based charge A transparent cover tape for a carrier tape for use in small chip packaging, characterized by containing 0.1 to 1 parts by weight of an inhibitor.