JP2015193686A - Carrier tape for electronic material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a carrier tape having an adhesive layer using a synthetic rubber containing a styrene-isoprene block copolymer and suppressed adhesive residue, and to suppress bleeding-out characteristics.SOLUTION: There is provided a carrier tape for electronic material having an adhesive layer, a substrate layer, and a release layer, where the adhesive layer contains a styrene-isoprene block copolymer, the styrene-isoprene block copolymer has a styrene ratio of 20 to 40 mass% and 35 mass% or less of diblock component, and a weight average molecular weight of 70,000 to 200,000.

Description

  The present invention relates to a carrier tape used for packaging, storage, transportation and the like of electronic parts such as semiconductors and microchips.

  The carrier tape is a tape used for storage, transportation, etc. by connecting and fixing a plurality of electronic components such as semiconductors and microchips. The carrier tape is formed with an adhesive layer capable of adhesively fixing a lead portion attached to the electronic component, and a part of the electronic component is fixed to the adhesive surface. Then, in a state where a plurality of electronic components are aligned and fixed by this carrier tape, they are stored and transported in an electronic device manufacturing factory or the like.

  In general, the lead part of the electronic component is fixed with two carrier tapes.

  Conventionally, solvent-based natural rubber has been generally used as a raw material for an adhesive layer of a carrier tape. However, in the tape application process where the fixed parts such as the lead parts of many electronic parts are sandwiched between two carrier tapes, there is a problem such as glue adhering to the application equipment. -It is desired to use an adhesive layer using a synthetic rubber containing an isoprene block copolymer.

  However, in the case of a pressure-sensitive adhesive using a synthetic rubber containing a styrene-isoprene block copolymer, when there is even one defective electronic component in a carrier tape in which a plurality of electronic components are aligned and fixed, In some cases, the lead portions and the like of a plurality of electronic components are once removed from the carrier tape, and there is a problem that adhesive residue is generated in a fixing portion such as a lead portion of a normal electronic component.

JP 2010-274931 A

  This invention makes it a subject to provide the carrier tape which has the adhesive layer using the synthetic rubber containing a styrene-isoprene block copolymer, Comprising: The adhesive residue was suppressed. Another object of the present invention is to suppress the so-called oozing-out property, in which adhesive adhesion occurs in the application equipment in the tape application process.

  Under the circumstances as described above, the present inventors have intensively studied. As a result, by adding a specific amount of styrene to the styrene-isoprene block copolymer and a specific amount of diblock component, the adhesive residue of the pressure-sensitive adhesive layer is obtained. Has been found to be suppressed. The present inventors further studied various conditions such as the molecular weight of the styrene-isoprene block copolymer, and as a result, completed the present invention.

Accordingly, the present invention provides the following sections:
Item 1. An electronic material carrier tape comprising an adhesive layer, a base material layer and a release layer, wherein the adhesive layer contains a styrene-isoprene block copolymer, and the styrene-isoprene block copolymer is 20 to 40 masses. A carrier tape having a styrene ratio of 25%, containing a diblock component of 35% by mass or less, and having a weight average molecular weight of 70,000 to 200,000.

  Item 2. The carrier tape according to claim 1, wherein a blending ratio of the styrene-isoprene block copolymer in the pressure-sensitive adhesive layer is 30 to 50%.

  Item 3. The carrier tape according to claim 1 or 2, wherein the pressure-sensitive adhesive layer contains a tackifier, oil, and calcium carbonate.

  Item 4. The carrier tape according to any one of claims 1 to 3, wherein a base material strength (MD) of the base material layer is 55 N / 10 mm or more.

  Item 5. The carrier tape according to any one of claims 1 to 4, wherein the adhesive has an elastic modulus of 90 MPa or more at 20 ° C and a thickness of the adhesive layer of 10 to 50 µm.

  According to the present invention, a synthetic rubber containing a styrene-isoprene block copolymer having a predetermined molecular weight is used, and a specific amount of styrene is added to the styrene-isoprene block copolymer, and a specific amount of diblock component is added. By using the pressure-sensitive adhesive layer using, it is possible to provide a carrier tape in which adhesive residue and bleeding are suppressed.

The outline of the layer structure in one Embodiment of this invention is shown.

  The present invention is a carrier tape for electronic materials comprising an adhesive layer, a base material layer and a release layer, wherein the adhesive layer contains a styrene-isoprene block copolymer, and the styrene-isoprene block copolymer is Provided is a carrier tape having a styrene ratio of 20 to 40% by mass, containing a diblock component of 35% by mass or less, and having a weight average molecular weight of 70,000 to 200,000.

  The present invention is characterized in that a specific amount of diblock component and styrene are used in the pressure-sensitive adhesive layer, and a styrene-isoprene block copolymer having a specific weight average molecular weight is blended.

  In the present invention, the styrene ratio of the styrene-isoprene block copolymer is 20 to 40% by mass, preferably 20 to 30% by mass, and more preferably 22 to 28% by mass.

  In the present invention, the styrene ratio of the styrene-isoprene block copolymer can be determined according to JIS K6383.

  In the present invention, the styrene-isoprene block copolymer means a block copolymer comprising a styrene block and an isoprene block.

  In the present invention, the diblock component refers to a block component in which only one set of styrene block (hard segment) and isoprene block (soft segment) is present in the styrene block polymer. More specifically, when the styrene block is represented by S and the isoprene block is represented by I, a diblock component having only one set of styrene block and isoprene block, such as SSS ... SSSIII ... III That's it. In addition, a component having two sets of styrene blocks and one set of isoprene blocks, such as SSS... SSSIII.

  The amount of the diblock component can be determined by measuring the molecular weight of GPC or the like and calculating the ratio of (styrene-isoprene monomer) during styrene-isoprene copolymerization.

  In this invention, content of the diblock component in a styrene-isoprene block copolymer is 35 mass% or less, Preferably it is 15-35 mass%, More preferably, it is 23-30 mass%.

  In the present invention, the weight average molecular weight of the styrene-isoprene block copolymer is 70,000 to 200,000, preferably 90,000 to 180,000, more preferably 110,000 to 170,000. In the present invention, the weight average molecular weight means a value measured by GPC.

  In the present invention, the blending ratio of the styrene-isoprene block copolymer in the pressure-sensitive adhesive layer is not particularly limited, but is, for example, 30 to 50% by mass, preferably 30 to 450,000% by mass, and more preferably 32 to It can set suitably in the range of 40 mass%.

  In the present invention, the pressure-sensitive adhesive layer may optionally contain at least one selected from the group consisting of a tackifier, oil and calcium carbonate.

  Examples of the tackifier include petroleum resins, terpene phenol resins, rosin ester resins, and the like. These tackifiers can be used alone or in combination of two or more. The blending amount of the tackifier is not particularly limited, and is appropriately set in the range of, for example, 20 to 40% by mass, preferably 25 to 40% by mass, more preferably 28 to 32% by mass as the content ratio in the adhesive layer. can do.

  Examples of the softener oil include naphthenic and paraffinic oils. These oils can be used alone or in combination of two or more. The blending amount of the oil is not particularly limited, and the content ratio in the pressure-sensitive adhesive layer may be appropriately set within a range of, for example, 30% by mass or less, preferably 5 to 120% by mass, more preferably 7 to 13% by mass. it can.

  The blending amount of calcium carbonate is not particularly limited, and is appropriately set in the range of, for example, 10 to 30% by mass, preferably 5 to 28% by mass, more preferably 15 to 25% by mass as the content ratio in the pressure-sensitive adhesive layer. can do.

  In the present invention, the elastic modulus of the pressure-sensitive adhesive layer at 20 ° C. is preferably 90 MPa or more, and more preferably 90 to 150 MPa. Moreover, in this invention, it is preferable that the thickness of an adhesive layer is 10-50 micrometers, and it is more preferable that it is 20-45 micrometers.

  It does not specifically limit as a raw material of a base material layer, Polyester-type resins, such as a thermoplastic polyester-type resin, a nonwoven fabric, paper, a craft paper, etc. are mentioned. Examples of the base material layer include those obtained by subjecting these resins to a stretching treatment such as uniaxial stretching or biaxial stretching and further forming a storage portion.

  In the present invention, the substrate strength (MD) of the substrate layer is not particularly limited. For example, it is 55 N / 10 mm or more, preferably 55 to 100 N / 10 mm, more preferably 55 to 70 N / 10 mm. Can be set. The base material strength (MD) can be measured by a JISZ0237 tensile test.

  In the carrier tape of the present invention, a conductive resin layer may be laminated on a base material layer. The material for the conductive resin layer is not particularly limited. For example, a material in which a conductive powder such as carbon black is contained in a thermoplastic resin such as an acrylic resin, a polyester resin, or a polyurethane resin can be given. It is done. Carbon black includes furnace black, acetylene black, channel black, and the like.

  In the present invention, for example, a surface coat layer may be laminated on the conductive resin layer. Here, as a surface coat layer, what mix | blended the filler in the thermoplastic resin etc. are mentioned, for example.

  The thermoplastic resin contained in the surface coat layer is not particularly limited. For example, acrylic resin, methacrylic resin, polyester resin, polyurethane resin, polyester urethane resin, vinyl acetate resin, polyvinyl alcohol resin, epoxy Based resins and the like. These thermoplastic resins can be used individually by 1 type or in mixture of 2 or more types.

  Examples of the filler include inorganic particles and organic particles. Examples of the inorganic particles include particles of calcium carbonate, magnesium carbonate, silicon oxide, calcium silicate talc, mica, calcium phosphate, magnesium phosphate, and the like. Examples of the organic particles include particles such as polymers or copolymers of vinyl monomers such as styrene, acrylic acid, methacrylic acid, acrylic acid, and methacrylic acid.

  The surface coat layer may contain a wax. Examples of the wax include natural wax and hydrocarbon wax. Examples of natural waxes include animal waxes such as lanolin, vegetable waxes such as castor oil hydrogenated wax, and mineral waxes such as montan wax. Examples of the hydrocarbon wax include polyethylene wax and polypropylene wax.

  In the carrier tape according to the present invention, a release layer may be laminated on the base material layer. Examples of the release layer material include silicone release agents and long-chain alkyl release agents. These release layer materials can be used singly or in combination of two or more. FIG. 1 shows an outline of the layer structure of a carrier tape in an embodiment having a release layer.

  EXAMPLES Hereinafter, although this invention is demonstrated concretely using an Example, it cannot be overemphasized that this invention is not limited to this Example.

Production Example 1 of Carrier Tape
40 parts by mass of a styrene-isoprene block copolymer (trade name “Quintac 3280” manufactured by Nippon Zeon Co., Ltd.), 30 parts by mass of petroleum resin (trade name “Quinton A-100” manufactured by Nippon Zeon Co., Ltd.), As a softener, 10 parts by mass of process oil (trade name “Shelf Rex 702” manufactured by Shell Chemical Co., Ltd.) and 20 parts by mass of calcium carbonate were mixed to obtain an adhesive layer composition. The above pressure-sensitive adhesive layer composition was applied to a base material (length 15 cm × width 0.6 cm × thickness softening agent 0.1 cm, material: kraft paper) to a thickness of 25 μm, and a carrier tape was manufactured.

Example 2 and Comparative Examples 1-3
Carrier tapes of Example 2 and Comparative Examples 1 to 3 were produced in the same manner as in Example 1 except that the styrene-isoprene block copolymer was used as a raw material shown in the following table.

Evaluation Test The carrier tapes of Examples 1 and 2 and Comparative Examples 1 to 3 were evaluated by the method described later.

Retention after sticking Tape is applied to a 0.7mm sn-plated terminal, measuring shear force when the terminal is pulled out from the tape after 60 ° C x 10 days. To do.

Adhesive residue Affixed to a 0.7 mm sn-plated terminal, and after 60 ° C x 10 days, when the terminal is pulled out from the tape, observe the adhesion of the adhesive to the terminal, no adhesive residue "○", adhesive residue 1/2 Less than △,
The adhesive residue is 1/2 or more and “x”.

Exudation Cut the tape into 10 mm x 100 mm, observe paste exudation from the end of the tape after pressing at 6.3 kg / cm 2, no exudation “○”, exudation less than 1/2 “△”, exudation 1 / 2 or more “×”.

Base material fracture strength is measured by a JISZ0237 tensile test using a tensile tester, and it is set to 55 × 10 mm or more “◯” and less than 55 N / 10 mm “×”.

Comprehensive evaluation The carrier tape is required to have excellent performance in all of retention properties after sticking, adhesive residue, seepage, and substrate breakage. Therefore, a comprehensive evaluation was performed based on the following criteria:
○: All items of retention after sticking, adhesive residue, seepage and substrate breakage are ○. Δ: All the above 4 items are ○ or Δ, and at least one item is Δ. ×: The above 4 items Among these, at least one item is x.

  The results are shown in Table 2 below.

Claims (5)

An electronic material carrier tape comprising an adhesive layer, a base material layer and a release layer, wherein the adhesive layer contains a styrene-isoprene block copolymer, and the styrene-isoprene block copolymer is 20 to 40 masses. A carrier tape having a styrene ratio of 25%, containing a diblock component of 35% by mass or less, and having a weight average molecular weight of 70,000 to 200,000.   The carrier tape according to claim 1, wherein a blending ratio of the styrene-isoprene block copolymer in the pressure-sensitive adhesive layer is 30 to 50%.   The carrier tape according to claim 1 or 2, wherein the pressure-sensitive adhesive layer contains a tackifier, oil, and calcium carbonate.   The carrier tape according to any one of claims 1 to 3, wherein a base material strength (MD) of the base material layer is 55 N / 10 mm or more.   The carrier tape according to any one of claims 1 to 4, wherein an elastic modulus of the adhesive at 20 ° C is 90 MPa or more and a thickness of the adhesive layer is 10 to 50 µm.