JP5701350B2 - Bottom cover tape for transporting electronic components - Google Patents

Description

  The present invention relates to a bottom cover tape for transporting electronic components, which is a component of an electronic component transport body used for transporting electronic components such as chip-type electronic components.

  When transporting an electronic component such as a chip-type electronic component, a bottom cover tape for transporting an electronic component (hereinafter referred to as a bottom cover tape) is provided on one surface (lower surface) of a carrier tape in which a plurality of punched holes are formed at regular intervals in the length direction. ) Is heat-sealed, and an electronic component transport body that uses the punched holes as storage pockets for electronic components is often used. An electronic component such as a chip-type electronic component (hereinafter sometimes simply referred to as “chip component”) is inserted into a storage pocket of the electronic component carrier, and a top cover tape is further heat-sealed on the upper surface of the carrier tape. Thus, the electronic component is enclosed in the electronic component carrier. Thus, the electronic component transport body is transported while being wound in a reel shape.

However, recently, a phenomenon that electronic components stored in a storage pocket of an electronic component transport body cannot be sucked by an air nozzle often occurs, and a decrease in suction rate has become a problem. The reasons are as follows: (1) As electronic parts become lighter, thinner and smaller, the electronic parts adhere to the bottom cover tape thermal adhesive layer surface due to static electricity and external force, and (2) the carrier tape thickness varies, resulting in air more than usual. Adhesion of electronic parts to the heat-bonded surface due to the nozzle being pressed, (3) Bottom cover tape thermal adhesive layer as the time from bonding the bottom cover tape to the carrier tape to inserting the electronic parts into the storage pocket is shortened It can be considered that the chip component is attached to the thermal adhesive layer when the chip component is not sufficiently solidified. Furthermore, when a solution is attempted by using a kneaded antistatic agent, there is a problem that the electrode part of the chip part is corroded due to contact with the adhesive layer surface of the chip part.

  Several proposals have been made for the purpose of solving the above-mentioned problems caused by such adhesion or fusion of electronic components. For example, Patent Documents 1 and 2 propose that the thermal adhesive layer is made of a specific resin or the like. In the proposal of patent document 1, it is set as the structure which contains the polyolefin resin as a base polymer, a petroleum resin, and a cationic antistatic agent in a predetermined ratio, respectively, and in the proposal of patent document 2, as a base polymer, And a saturated saturated hydrocarbon resin, an amphoteric surfactant and / or a nonionic surfactant at a predetermined ratio.

Further, in Patent Document 3, an antistatic agent in which a resin mainly composed of a solated oxide layer and an anionic water-based acrylic urethane resin is dispersed in water is applied to a support base material layer or added to a thermal adhesive layer. Propose to do. Patent Document 4 proposes a laminated body of Japanese paper or a hydrophilic polymer base material and a thermoplastic resin base material, and Patent Document 5 proposes a plastic film as a supporting base material layer. .

JP 2001-3014 A JP 2002-211677 A JP 2005-178811 A JP 2002-114267 A JP 2008-265787 A

  However, the proposals of the patent documents have the following problems. First, in the proposals of Patent Documents 1 and 2, electronic components may adhere in a harsh environment. In this case, the adhesion of electronic components can be effectively suppressed by using polypropylene having a surface hardness higher than that of polyethylene as the base polymer, but the sealing strength of the bottom cover tape itself against the carrier tape is lowered.

  In the case of the proposal of Patent Document 3, it is effective to adhere parts caused by static electricity under general environmental conditions, but in a high humidity environment or a special environment such as pressing an air nozzle unrelated to the generation of static electricity. There is no effect on the adhesion of parts under certain conditions. In addition, when the antistatic agent is applied to the support base material layer or added to the thermal adhesive layer, the adhesion of the electronic component cannot be solved, and in the latter case, contamination due to the antistatic agent bleed occurs as a disadvantage, There may be a demerit that makes it difficult to control the amount of bleed. Further, as proposed in Patent Documents 4 and 5, even if a specific resin or the like is used as the support base material, it is expected that the adhesion of the electronic components cannot be solved similarly. Furthermore, in addition to the characteristics of the thermal adhesive layer itself and the effect of the additive, the electronic component adhesion mechanism also affects the thermal adhesive layer in the storage pocket in a direction in which unevenness is reduced by heating during sealing. Also, it is necessary to consider the possibility that the contact area with the electronic component becomes large.

SUMMARY OF THE INVENTION An object of the present invention is to provide a bottom cover tape that can prevent adhesion of electronic components due to generation of static electricity or pressing of an air nozzle in a high humidity environment.

  The inventors of the present invention have made extensive studies to solve the above problems, and provided an antistatic layer containing fine particles on the surface of the thermal adhesive layer, forming irregularities on the surface of the antistatic layer, It has been found that each of the above problems can be solved by reducing the contact area, and the present invention has been completed.

  That is, according to the present invention, the object is that a support base layer, a thermal adhesive layer, and an antistatic layer are sequentially laminated, and the antistatic layer contains at least an antistatic agent and fine particles, The content of the fine particles is 40% by weight or more when the total amount of the constituent materials in the antistatic layer is 100% by weight.

The fine particles can be composed of an organic material, an inorganic material, or a combination thereof, and preferably have an average particle size of 1 μm or less. The antistatic agent may be a surfactant type antistatic agent or a polymer type antistatic agent. The fine particles and the antistatic agent are preferably set to have a weight ratio of fine particles: antistatic agent solid content = 1 to 8: 1.

The method for forming the antistatic layer on the surface of the thermal adhesive layer is not particularly limited, but is preferably by coating. The surface resistivity of the antistatic layer thus obtained is preferably 9.9 × 10 ¹² Ω / □ or less.

  Since the bottom cover tape of the present invention is further provided with an antistatic layer containing a predetermined amount of fine particles on the surface of the thermal adhesive layer, the chip component is not in a state where the thermal adhesive layer of the bottom cover tape is sufficiently solidified. Even when it is inserted, the electronic component stored in the storage pocket of the electronic component carrier adheres to the bottom cover tape in a high humidity environment. It can suppress adhering to a cover tape.

It is a cross-sectional side view which shows the structure of one Embodiment of the bottom cover tape for electronic component conveyance of this invention.

  Next, embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a cross-sectional side view schematically showing a configuration of an embodiment of a bottom cover tape for conveying an electronic component according to the present invention. As shown in this figure, the bottom cover tape 1 for conveying an electronic component according to this embodiment includes a support base layer 10, a thermal adhesive layer 11, an antistatic agent 12, and fine particles 13 having a predetermined average particle diameter. The antistatic layers 15 are sequentially laminated.

[Supporting substrate layer 10]
The supporting base material layer 10 can be composed of at least one supporting base material made of paper or hydrophilic polymer (hereinafter referred to as a paper base material or a hydrophilic polymer base material, respectively).

Examples of the paper substrate include various papers such as Japanese paper, mixed paper, thin paper, cardboard, kraft paper, crepe paper, clay coated paper, fine paper, glassine paper, kurpack paper, synthetic paper, and composite paper. Such paper substrates, the range of basis weight 5 to 50 g / ^{m 2,} preferably suitably selected from the range of 10 to 30 g / ^{m 2.}

Examples of the hydrophilic polymer in the hydrophilic polymer substrate include polyvinyl alcohol; polyvinyl acetal such as polyvinyl butyral; nitrocellulose, regenerated cellulose (cellophane), carboxymethylcellulose, hydroxyethylcellulose, cellulose acetate, cationized cellulose, methylcellulose, hydroxy Examples include hydrophilic cellulose compounds such as ethyl methyl cellulose, hydroxypropyl methyl cellulose, hydroxypropyl cellulose; polyethylene oxide; polyethylene glycol; polyethylene imine; sodium polyacrylate; sodium polystyrene sulfonate. In the case of using a hydrophilic polymer substrate, among the hydrophilic polymers, polyvinyl alcohol, polyvinyl acetal, and a hydrophilic cellulose compound can be suitably used.

The paper substrate and hydrophilic polymer substrate may be used alone or in combination of two or more. In the case of the hydrophilic polymer, one layer or a laminate of those formed into a film shape is used as a hydrophilic polymer substrate. In this case, the film thickness can be appropriately set in the range of 5 to 100 μm, preferably 10 to 50 μm.

Further, when the paper substrate and the hydrophilic polymer substrate are used in combination, for example, the support substrate layer 10 can be configured by laminating a paper substrate and a hydrophilic polymer substrate. In this case, the supporting substrate layer 10 is formed by, for example, a method of extrusion laminating a hydrophilic polymer substrate on a paper substrate, a solution containing a hydrophilic polymer, or a molten hydrophilic polymer resin on a paper substrate. It can form by the method of apply | coating to. In the present invention, a paper substrate may be impregnated with a hydrophilic polymer. By combining the paper base and the hydrophilic polymer base in this manner, the adsorption of moisture in the air by the support base 10 can be further enhanced, and the generation of static electricity can be further suppressed. In this case, it is possible to suppress or prevent adhesion of the electronic component to the thermal adhesive layer due to static electricity.

  In addition, the support base material layer 10 can be added with commonly used additives as necessary. Examples of such additives include antioxidants, ultraviolet absorbers, softeners, rust inhibitors, antistatic agents (described later), conductive metal powders, organic conductive polymer agents, silane coupling agents, and the like. Can be mentioned. Further, the surface of the support base layer 10 can be subjected to corona treatment for the purpose of modifying the surface.

[Thermal bonding layer 11]
For the thermal adhesive layer 11, a polyolefin resin, an ethylene-unsaturated carboxylic acid copolymer, an ethylene- (meth) acrylic acid ester copolymer, an ethylene-vinyl acetate copolymer (EVA), or the like is used as a base polymer. it can. Examples of the polyolefin resin include low density polyethylene, linear low density polyethylene, metallocene catalyzed polyethylene, medium density polyethylene, high density polyethylene, polypropylene, α-olefin copolymer (ethylene-propylene copolymer, ethylene-butene-1). Copolymer, propylene-butene-1 copolymer, etc.). Examples of the ethylene-unsaturated carboxylic acid copolymer include an ethylene-acrylic acid copolymer (EAA) and an ethylene-methacrylic acid copolymer (EMAA). Examples of the ethylene- (meth) acrylic acid ester copolymer include an ethylene-methyl acrylate copolymer, an ethylene-ethyl acrylate copolymer (EEA), and an ethylene-methyl methacrylate copolymer. These may be used alone or in combination of two or more. Of these base polymers, polyolefin resins can be suitably used.

  The thermal adhesive layer 11 further includes, for example, an antioxidant, an ultraviolet absorber, a softener, a rust inhibitor, an antistatic agent (described later), a conductive metal powder, an organic conductive polymer agent, and a silane as necessary. Conventionally known additives such as coupling agents can be added. Specific examples of the conductive metal powder include gold, silver, nickel, aluminum, copper, and metal oxide powders such as tin oxide, zinc oxide, and titanium oxide. Specific examples of the organic conductive polymer agent include Si-based organic compounds, polypyrrole, polyaniline, polythiophene, and the like. These may be added alone or in combination of two or more.

A colorant and a light blocking agent may also be added to the thermal adhesive layer 11. Such colorants and light blocking agents include, for example, inorganic materials such as carbon black, titanium oxide, zinc oxide, iron oxide, aluminum oxide, cyanine blue, cyanine green, miloli blue, selenium blue, cadmium red, cadmium yellow, cadmium orange. And pigments such as petals, ultramarine blue, and phthalocyanine blue. These may be added directly, but it is preferable to use a master batch from the viewpoint of workability. The base resin of the master batch is preferably LDPE or PP. Moreover, stabilizers, such as antioxidant, a deterioration inhibitor, and an ultraviolet absorber, can be added as needed.

  The thickness of the thermal bonding layer 11 is not particularly limited and can be appropriately set in consideration of the adhesiveness with the electronic component carrier, etc., but is usually in the range of 5 to 100 μm, preferably 5 to 50 μm, more preferably 10 to 40 μm. It is said. When the thickness of the heat bonding layer 11 is less than 5 μm, the adhesiveness with the carrier tape as the adherend is deteriorated, and the mechanical strength of the bottom tape itself is remarkably lowered. Also, if the thickness of the thermal adhesive layer 11 exceeds 100 μm, the total thickness of the bottom cover tape increases, resulting in poor sealing due to insufficient heat transfer, and handling properties due to weight increase in the case of reel winding. Problems such as lowering.

  A method for forming the thermal bonding layer 11 is not particularly limited. For example, a conventional method such as an extrusion lamination method or a dry lamination method can be used.

[Antistatic layer 15]
As shown in FIG. 1, the antistatic layer 15 contains at least an antistatic agent and fine particles. Below, the fine particle 13 is demonstrated first.

(Fine particles 13)
The content of the fine particles 13 contained in the antistatic layer 15 is 40% by weight or more when the total amount of the constituent materials in the layer is 100% by weight.

The fine particles 13 can have an average particle diameter of 1 μm or less, preferably 0.005 to 0.5 μm, more preferably 0.02 to 0.2 μm. This is because if the average particle size of the fine particles exceeds 1 μm, the surface roughness (Ra) of the antistatic layer 15 is increased due to the presence of these extraneous fine particles, and the adhesion to the carrier tape is hindered. The influence on the adhesiveness becomes smaller as the average particle size of the fine particles becomes smaller in the above range.

The fine particles 13 can be appropriately selected from various organic materials and inorganic materials. Specific examples of the organic fine particles include fine particles made of an organic material such as an acrylic resin; fine particles made of an organic conductive polymer such as a Si-based organic compound, polypyrrole, polyaniline, and polythiophene. . Examples of the fine particles of inorganic materials include silica particles; carbon black; metal fine particles such as gold, silver, nickel, aluminum and copper; metal oxides such as tin oxide, zinc oxide and titanium oxide; Conductive fine particles imparted with conductivity; conductive fine particles imparted with conductivity to sulfides such as zinc sulfide, copper sulfide, cadmium sulfide, nickel sulfide and palladium sulfide. Preferably, the fine particles 13 are formed of an organic material. As is clear from these examples, the fine particles 13 may be conductive or insulating.

(Antistatic agent 12)
As the antistatic agent 12, a polymer type antistatic agent or a surfactant type antistatic agent can be used. The polymer type antistatic agent is, for example, a polymer type antistatic agent called a persistent antistatic agent or a permanent antistatic agent. Specifically, for example, ionomers such as polyethylene oxide, polypropylene oxide, polyethylene glycol, polyester amide, polyether ester amide, polyether polyolefin, ethylene-methacrylic acid copolymer, polyethylene glycol methacrylate copolymer, etc. In one or a mixture of two or more selected from quaternary ammonium salts of the above, a copolymer of two or more, and a copolymer thereof with another resin such as polypropylene, etc., a molecular chain Examples thereof include resins having a polar group and capable of complexing or solvating an inorganic salt or a low molecular weight organic protonic acid salt, wherein the inorganic salt or organic protonic acid salt is complexed or solvated. Also good. Of these, polyether polyolefin and polyether ester amide are preferred, and polyether polyolefin is particularly preferred from the viewpoint of compatibility with polypropylene resin and cyclic polyolefin resin and antistatic performance.

  The surfactant type antistatic agent is not particularly limited, and conventionally known cationic surfactants, anionic surfactants, nonionic surfactants, amphoteric surfactants, and the like can be used. Examples of the cationic surfactant include quaternary ammonium salts and pyridine derivatives. Examples of the quaternary ammonium salt include a tetraalkylammonium salt and a trialkylbenzylammonium salt. Among these, it is more preferable to use a quaternary ammonium salt type acrylic copolymer resin. Specific examples thereof include “Bondip PA100” (manufactured by Altec).

Examples of the anionic surfactant include alkyl sulfate ester salts, alkyl aromatic sulfonates, succinate sulfonates, and phosphate ester salts.

Nonionic surfactants include, for example, alcohol type (polyethylene glycol, etc.), ether type (polyoxyethylene alkyl ether, polyoxyalkylene alkyl ether, polyoxyethylene alkylphenyl ether, etc.), ester type (sorbitan fatty acid ester). , Polyoxyethylene sorbitan fatty acid ester, polyoxyethylene sorbitol fatty acid ester, glycerin fatty acid ester, etc.), amine type (polyoxyethylene alkylamine, alkyldiethanolamine, hydroxyalkylamine monoethanolamine, etc.), glycerin type (polyoxyethylene glyceride, etc.) ), Amide type (alkyl alkanolamide, alkyldiethanolamide, polyoxyethylene alkylamide, etc.) It is.

Furthermore, examples of amphoteric surfactants include alkyl betaines, alkyl imidazolium betaines, hydroxyalkyl imidazoline sulfates, betaine carboxylic acid derivatives, and imidazoline derivatives.

These antistatic agents may be used alone or in a cationic surfactant, an anionic surfactant, a nonionic surfactant and an amphoteric surfactant, or a surfactant 2 different from each other. Can be used in combination with more than one species.

The blending ratio of the antistatic agent 12 and the fine particles 13 with respect to the solid content of the antistatic agent 12 is not particularly limited and can be appropriately set, but preferably the fine particles: antistatic agent = 1-8: 1. More preferably, the blending ratio (all by weight) is 1 to 6: 1, and particularly preferably 1 to 4: 1. This blending ratio can be set as appropriate depending on the type of the fine particles 13 so that suitable adhesion prevention of electronic components can be achieved. When the blending ratio of the fine particles 13 is less than the preferable blending ratio, the prevention of adhesion of the electronic component to the bottom cover tape is not sufficient, and when the blending ratio exceeds the preferable blending ratio, the sealing property to the carrier tape is inhibited.

In the present invention, if necessary, a colorant and a light blocking agent can be added to the antistatic layer 15 as long as the properties thereof are not affected. Such colorants and light blocking agents include, for example, inorganic materials such as carbon black, titanium oxide, zinc oxide, iron oxide, aluminum oxide, cyanine blue, cyanine green, miloli blue, selenium blue, cadmium red, cadmium yellow, cadmium orange. And pigments such as petals, ultramarine blue, and phthalocyanine blue. These may be added directly, but it is preferable to use a master batch from the viewpoint of workability. The base resin of the master batch is preferably LDPE or PP. Further, if necessary, stabilizers such as an antioxidant, an anti-degradation agent, and an ultraviolet absorber can be added within a range that does not affect the properties of the antistatic layer 15.

  The antistatic layer 15 can be formed on the surface of the thermal adhesive layer 11 by an appropriate method. For example, the antistatic agent and fine particles may be mixed and then laminated on the surface of the thermal adhesive layer by a method such as extrusion. The antistatic agent and fine particles may be mixed in an organic solvent such as alcohol. The dispersed liquid dispersion may be applied to the surface of the thermal adhesive layer 11 to form. The latter is preferably formed by application. The surface (exposed surface) of the antistatic layer 15 may be subjected to corona treatment to improve the surface.

  There is no restriction | limiting in particular in the thickness of the antistatic layer 15, It can set suitably. When applied, the thickness is usually about 0.5 μm.

  The surface of the antistatic layer 15 thus formed is formed as an uneven surface due to the presence of contained fine particles. There is no particular limitation on the surface roughness (Ra) of the uneven surface conforming to JIS B0601, but it is usually about 0.1 μm. The surface roughness (Ra) is measured by a method defined by JIS standards.

The surface resistivity of the antistatic material layer 15 in accordance with JIS B0601 is preferably 9.9 × 10 ¹² Ω / □ or less. When the surface resistivity exceeds the above value, it is difficult to flow the generated static electricity, and the possibility that electronic components due to static electricity adhere to the bottom cover tape increases.

[Raw materials used]
(1) Thin paper (thickness 40 μm, basis weight 18 g / m ² )
(2) Low density polyethylene (LPDE, trade name: Petrocene P203, manufactured by Tosoh Corporation)
(Density 0.919g / cm ³ , MFR 8g / 10min)
(3) Polypropylene (trade name: Novatec FL02A, manufactured by Nippon Polypro)
Density 0.90g / cm ³ , MFR 20g / 10min
(4) Antistatic agent (trade name: Bondip (registered trademark) PA100, manufactured by Altec)
(5) Cationic surface active antistatic agent (trade name: Electro Stripper (registered trademark) TS-7B, manufactured by Kao Corporation)
(6) Acrylic fine particles (trade name Advancel (registered trademark) NS, manufactured by Sekisui Chemical Co., Ltd.)
Average particle size 150nm
(7) Fine silica particles (trade name Snowtex (registered trademark) ST-ZL, manufactured by Nissan Chemical Industries, Ltd.)
Average particle size 100nm
(8) Silica particles (trade name NIPSEAL (registered trademark) SS-70 manufactured by Tosoh Silica)
Average particle size 4.1μm
(9) Methanol reagent special grade (Wako Pharmaceutical Co., Ltd.)

(Example 1)
A thin paper was used as a support substrate, and a low-density polyethylene was extruded thereon by an extrusion laminator to laminate a 25 μm thick thermal adhesive layer. Next, a dispersion in which 2% by weight of acrylic fine particles are dispersed in methanol with respect to 1% by weight of the solid content of the antistatic agent (the total amount of the dispersion is 100% by weight) is prepared. After coating with a gravure roll so that the coating amount after drying was 0.5 g / m ² to form an antistatic layer, the bottom cover tape of Example 1 was obtained by slitting to a predetermined width. .

(Example 2)
A bottom cover tape of Example 2 was obtained in the same manner as in Example 1 except that silica fine particles were used in place of the acrylic fine particles.

(Example 3)
A bottom cover tape of Example 3 was obtained in the same manner as in Example 1 except that the amount of the acrylic fine particles in the alcohol dispersion was changed to 4% by weight.

(Comparative Example 1)
A bottom cover tape of Comparative Example 1 was obtained in the same manner as in Example 1 except that in the alcohol dispersion, the amount of the acrylic fine particles was changed to 0.5% by weight.

(Comparative Example 2)
In the composition of Example 1, a bottom cover tape of Comparative Example 2 was obtained by the same method as Example 1 except that silica particles having an average particle diameter of 4.1 μm were used instead of acrylic fine particles having an average particle diameter of 150 nm. It was.

(Comparative Example 3)
After laminating a thermal adhesive layer made of low density polyethylene to a thickness of 25 μm on a thin paper as a supporting substrate by an extrusion laminator, a bottom cover tape of Comparative Example 3 was obtained by slitting to a predetermined width. .

(Comparative Example 4)
On a thin paper as a supporting substrate, low-density polyethylene was extruded by an extrusion laminator, and a thermal adhesive layer having a thickness of 25 μm was laminated. Next, 1% by weight of a solid content of an antistatic agent (manufactured by Altec: Bondip PA100) was diluted with alcohol to obtain a predetermined liquid. The obtained liquid was coated with a gravure roll so that the coating amount after drying was 0.5 g / m ^2, and then slit processing was performed to a predetermined width to obtain a bottom cover tape.

(Comparative Example 5)
After laminating an adhesive layer made of polypropylene to a thickness of 25 μm on a thin paper as a supporting substrate using an extrusion laminator, a bottom cover tape of Comparative Example 5 is obtained by slitting to a predetermined width. It was.

(Comparative Example 6)
On a thin paper as a supporting substrate, a mixture of 0.5% by weight of a cationic surfactant type antistatic agent with 100% by weight of low-density polyethylene was extruded and extruded by a laminator, and heat of 25 μm thickness was obtained. After laminating the adhesive layer, the bottom cover tape of Comparative Example 6 was obtained by slitting to a predetermined width.

[Evaluation method]
After bonding the bottom cover tapes of Examples 1 to 3 and Comparative Examples 1 to 6 to one side of the carrier tape in the following manner, the following evaluation methods were used. These evaluation results are shown in Table 2. In Table 2, for each measurement result, a two-step evaluation of ○ (good) and × (bad) or a three-step evaluation of ○ (good), △ (generally good), and × (bad) was made. Is described in the “judgment result” column.

1. Adhesive force Each of the above examples and comparative examples was applied to the lower surface of a paper carrier tape (made by Hokuetsu Paper Co., Ltd., trade name: HOCTO-60) using a heat sealing machine (taping machine manufactured by Tokyo Wells, model TWA-6903). The bottom cover tape obtained in (1) was heat-sealed under sealing conditions of 150 ° C. and a iron pressure of 1.5 kgf. Then, the adhesive strength of the sample that was allowed to stand for 24 hours in an environment of 23 ° C. and 50% RH was measured using a peel tester under conditions of a peel speed of 300 mm / min and a peel angle of about 180 °.

Determination about the measurement result of adhesive force was performed based on the following criteria.
○: 50 gf / 15 mm or more ×: less than 50 gf / 15 mm

2. Surface resistivity After manufacturing, each bottom cover tape was allowed to stand in a 23 ° C., 50% RH environment for 24 hours and then subjected to surface resistance using Hiresta UP (manufactured by Mitsubishi Chemical Corporation) in a 23 ° C., 50% RH environment The rate was measured. The measuring method was based on JIS K6911.

The determination of the measurement result of the surface resistivity was made based on the following criteria.
○: Less than 9.9 × ^{10 10} Ω / □ Δ: 9.9 × ^{10 10} or more and less than 9.9 × ^{10 12} Ω / □ ×: 9.9 × 10 ¹² Ω / □ or more

3. Chip Adhesion Each bottom cover tape is heat-sealed under the condition of 170 ° C. on the lower surface of the paper carrier tape using the heat sealing machine to produce an electronic component transport body, and 24 ° C. in an environment of 23 ° C. and 50% RH. Cured for hours. Thereafter, three electronic component carriers each storing 20 chip components of 1005 size (1.0 mm × 0.5 mm) in a square hole-shaped storage pocket were prepared. Then, these three electronic component carriers were fixed to the glass plate in such a manner that the surface on the bottom cover tape side was brought into close contact with the glass plate surface. The electronic component carrier was set at a predetermined position on the lower portion of the pressing tester (manufactured by Shimadzu Corporation) with the glass plate facing down, and only the glass plate was set at a predetermined position on the upper portion of the pressing tester. The upper part was lowered and pressed at a speed of 1 mm / min from a state in which the lower surface of the glass plate and the upper surface of the electronic component carrier set on the lower part were in contact with each other until a predetermined pressing depth was reached. The pressing depth at this time was set to two levels of 0.15 mm and 0.50 mm. Thereafter, the lower part of the electronic component carrier was removed from the testing machine together with the glass plate, and immediately inverted to count the number of electronic components adhered.

This chip adhesion determination was performed according to the following criteria.
○: Less than 5 Δ: 5 or more and less than 10 ×: 10 or more

  From the results in Table 2, it is clear that the bottom cover tapes of Examples 1 to 3 exhibit very good adhesion and surface resistivity. Further, it has been found that the chip part adhesion results are generally good to good in proportion to the amount of fine particles added to the antistatic layer.

  On the other hand, in Comparative Example 1, since the blending amount of fine particles was reduced, the adhesion to parts was inferior. Moreover, in the comparative example 2, although general-purpose silica particles are used instead of fine particles, adhesion to parts is excellent, but adhesion is inferior. In Comparative Example 3, since the antistatic layer is not provided on the surface of the thermal adhesive layer, the adhesion to the carrier tape is good, but the surface resistivity and chip adhesion are poor. In Comparative Example 4, an antistatic layer is provided on the surface of the thermal adhesive layer. Since the antistatic layer does not contain fine particles, the adhesion to the carrier tape and the surface resistivity are good. , Chip adhesion is poor. Further, in Comparative Example 5, since the thermal adhesive layer was formed with polypropylene instead of the low density polyethylene and the antistatic layer was not provided, the chip adhesion was good, but the adhesion with the carrier tape and the surface The resistivity is inferior. Furthermore, in Comparative Example 6, an antistatic layer made of a cationic surface active antistatic agent is provided on the surface of the thermal adhesive layer in place of the antistatic agent of Example 1, and the antistatic layer contains fine particles. Since the structure is not, the adhesion to the carrier tape is good and the surface resistivity is generally good, but the chip adhesion is poor. Further, the bleed material of the surfactant type antistatic agent easily contaminates the component and easily causes corrosion of the component.

  As described above, the bottom cover tape of the present invention is used in a high humidity environment or when static electricity is generated even when the chip component is inserted in a state where the thermal adhesive layer of the bottom cover tape is not sufficiently solidified. And an excellent effect that the electronic component stored in the storage pocket of the electronic component transport body can be prevented from adhering to the bottom cover tape by pressing the air nozzle.

DESCRIPTION OF SYMBOLS 1 ... Bottom cover tape for electronic component conveyance, 10 ... Support base material layer, 11 ... Thermal adhesive layer, 12 ... Antistatic agent, 13 ... Fine particle, 15 ... Antistatic Layer, Ra ... surface roughness

Claims (8)

A support base material layer, a thermal adhesive layer, and an antistatic layer are sequentially laminated. The antistatic layer contains at least an antistatic agent and fine particles, and the total amount of the constituent materials in the antistatic layer is 100 wt. The bottom cover tape for transporting electronic parts, wherein the content of the fine particles is 40% by weight or more.   The electron transport bottom cover tape according to claim 1, wherein the fine particles have an average particle size of 1 μm or less.   The bottom cover tape for electron transport according to claim 1 or 2, wherein the fine particles are made of an organic material, an inorganic material, or a combination thereof. The bottom cover tape for transporting electronic components according to claim 1, wherein the antistatic agent is a surfactant type antistatic agent or a polymer type antistatic agent. 5. The electron transport according to claim 1, wherein a mixing ratio of the fine particles and the antistatic agent is, as a weight ratio, fine particles: solid content of the antistatic agent = 1 to 8: 1. Bottom cover tape. The bottom cover tape for electron conveyance according to any one of claims 1 to 5, wherein the antistatic layer is applied to a surface of the thermal adhesive layer. The bottom cover tape for electron conveyance according to any one of claims 1 to 6, wherein a surface of the antistatic layer is subjected to corona treatment. The surface resistivity of the antistatic layer is 9.9 × 10 ¹² Ω / □ or less. The bottom cover tape for electron transport according to any one of claims 1 to 7.

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