JP5430887B2 - Cover tape - Google Patents

Description

  The present invention relates to a cover tape.

  In recent years, when storing, transporting, and mounting electronic components, carrier tapes that store electronic components in a concave electronic component storage unit at a constant pitch are widely used. After the electronic component is stored in the electronic component storage portion of the carrier tape, the cover tape serving as a lid member of the electronic component storage portion is sealed to prevent the electronic component from being contaminated and dropped off. The cover tape has a sealant layer containing a heat-sealable thermoplastic resin component and a pressure-sensitive adhesive and a base material layer for sealing the carrier tape. The cover tape is required to have transparency and an antistatic function, and many inventions have been reported for such a request (for example, Patent Document 1).

The cover tape is generally distributed as a so-called record winding body wound concentrically on a winding core. In many cases, the core of the cover tape is a plastic core such as ABS resin or polystyrene resin that matches the width of the cover tape.
JP 2005-126081 A

However, the wound body of the cover tape causes expansion and contraction of the cover tape and the winding core due to external factors such as temperature. In such expansion and contraction, since the degree and direction of expansion and contraction of the cover tape and the winding core are different, if the expansion and contraction is repeated during storage and transportation, a gap between the cover tapes in the shape of the record winding, so-called “ There was a case where a part of "" was generated and collapsed during storage and transportation. In particular, along with the lengthening of the carrier tape, the cover tape tends to be lengthened recently, and it is easily affected by external factors during transportation and storage. ”Is easy to collapse and sometimes difficult to handle. In addition, when the cover tape is extended, there is a problem that the cover tape collapses when rotated on the cover tape mounting shaft of the apparatus.
Then, this invention aims at the cover tape which can prevent winding collapse at the time of transport, storage, and use as a wound body.

  The cover tape of the present invention is a laminate in which a base material layer and a sealant layer containing a sealant material are positioned as surface layers, and the static friction coefficient between the surface of the base material layer and the surface of the sealant layer is 0.70 or less. It is characterized by being.

  The sealant layer preferably has substantially spherical particles (hereinafter sometimes referred to as spherical particles) having an average particle diameter of 0.01 to 20 μm, and the particles have a CV value represented by the following formula (1). Is preferably 45% or less, and 0.5 to 10 parts by mass of the particles are preferably added to 100 parts by mass of the sealant material in the sealant layer. The particles are preferably made of at least one selected from the group consisting of acrylic resins, styrene resins, melamine resins, and polyamide resins, and include indium tin oxide (ITO), antimony-doped tin oxide. It is preferably composed of at least one selected from the group consisting of (ATO: Antimony Tin Oxide) and zinc oxide, and is preferably silica.

  CV value (%) = (standard deviation of particle size distribution ÷ average particle size) × 100 (1)

  According to the cover tape of the present invention, it is difficult to cause collapse during transportation, storage, and use as a wound body.

The cover tape of the present invention is a laminate in which a base material layer and a sealant layer are positioned as surface layers, and the coefficient of static friction between the surface of the base material layer and the surface of the sealant layer is 0.70 or less. An example of an embodiment of the cover tape of the present invention will be described with reference to FIG. FIG. 1 is a cross-sectional view of the cover tape 10.
As shown in FIG. 1, the cover tape 10 is provided with a sealant layer 30 on one surface of a base material layer 20 via an intermediate layer 40. The sealant layer 30 is composed of spherical particles 34 and a sealant material. On the side surface 32 of the sealant layer, convex portions are formed by the spherical particles 34 exposed on the surface of the sealant layer 30 or the sealant material 36 covering the surfaces of the spherical particles 34.

(Base material layer)
The base material layer 20 is not particularly limited, but an insulating polymer film having high transparency, sufficient strength not to be cut when peeled from the carrier tape, and excellent dimensional stability against the environment and heat is suitable. Used for.
Examples of the insulating polymer film include polyethylene terephthalate, polyethylene naphthalate, polypropylene, polyethylene, polyamide, polycarbonate, polyimide, polyetherimide, polyamideimide, polyethersulfone, polysulfone, polyphenylene sulfide, and polyarylate. A laminated film in which is laminated. Among these, polyethylene terephthalate is preferable from the viewpoint of strength, heat resistance, and transparency. In addition, when laminating | stacking a film, well-known processes, such as a roughening process, a corona discharge process, a plasma discharge process, a primer process, an anchor coat process, may be given to the bonding surface previously.

  Although the thickness of the base material layer 20 is not specifically limited, 12-50 micrometers is preferable. If the thickness of the base material layer 20 is 12 μm or more, the cover tape is difficult to break, and if it is 50 μm or less, sufficient flexibility can be secured and heat conduction can be performed quickly at the time of sealing. Can be sealed.

(Sealant layer)
The sealant layer 30 is a layer that includes a sealant material 36 that can be sealed with the carrier tape, and spherical particles 34.

  The thickness of the sealant layer 30 is preferably 1 to 50 μm, and more preferably 5 to 30 μm. If the thickness of the sealant layer 30 is 1 μm or more, sufficient seal strength with the carrier tape can be secured, and if it is 50 μm or less, the seal strength when peeling from the carrier tape can be prevented from becoming too high, and the carrier The cover tape 10 can be easily peeled from the tape.

<Spherical particles>
By including the spherical particles 34, the sealant layer 30 can reduce the static friction coefficient between the sealant layer side surface 32 and the base material layer side surface 22 to 0.70 or less.
The spherical particles 34 have an average particle diameter of 0.01 to 20 μm, preferably 1 to 10 μm. If it is less than 0.01 μm, the convex portion formed on the side surface 32 of the sealant layer is too small, and the range in which the side surface 32 of the sealant layer 32 and the side surface 22 of the base material layer are in close contact with each other increases the static friction coefficient to 0.70 or less. There is a possibility that it cannot be adjusted. If the thickness exceeds 20 μm, the protruding portion protruding from the sealant layer 30 becomes too large, and the protruding portion may deeply bite into the base material layer 20 and the static friction coefficient may not be adjusted to 0.70 or less.

  The average particle diameter of the spherical particles 34 is a mass average particle diameter and is a value obtained by a Coulter counter method. For example, it can be measured by Multisizer 3 (manufactured by Beckman Coulter, Inc.).

  The spherical particles 34 are substantially spherical particles and include not only true spheres but also flat spherical particles. For example, the degree of flatness of the spherical particles 34 is preferably spherical in the range of 1/1 to 3/1 in the ratio expressed by the maximum diameter / minimum diameter.

  The spherical particles 34 preferably have a CV value represented by the following formula (1) of 45% or less, and more preferably 20% or less. If the CV value exceeds 45%, the variation in the size of the spherical particles 34 becomes too large, and the size of the convex portions on the side surface 32 of the sealant layer becomes uneven. For this reason, the location where the sealant layer side surface 32 and the base material layer side surface 22 are in close contact with the location where the convex portion is in contact with the base material layer side surface 22, and the static friction coefficient of the entire sealant layer side surface 32 is reduced to 0. This is because it becomes difficult to control to 70 or less.

  CV value (%) = (standard deviation of particle size distribution ÷ average particle size) × 100 (1)

  In the above formula (1), the standard deviation of the particle size distribution is a value obtained by the Coulter counter method. For example, it can be measured by Multisizer 3 (manufactured by Beckman Coulter, Inc.).

  The addition amount of the spherical particles 34 to the sealant layer 30 is not particularly limited, but is preferably 0.5 to 10 parts by mass, and 1 to 5 parts by mass with respect to 100 parts by mass of the sealant material 36. More preferred. When the amount is less than 0.5 parts by mass, there are too few convex portions formed on the side surface 32 of the sealant layer, and the range in which the side surface 32 of the sealant layer and the side surface 22 of the base material layer are in close contact with each other increases. The following adjustments may not be possible. If the amount exceeds 10 parts by mass, the number of convex portions protruding from the sealant layer 30 increases, and the number of portions where the convex portions bite into the base material layer 20 increases, and the static friction coefficient may not be adjusted to 0.70 or less. It is.

Examples of the material of the spherical particles 34 include organic particles, metal oxide particles, and inorganic particles. Among these, the organic particles can be made into a shape closer to a true sphere, and variations in individual shapes can be reduced, so that the static friction coefficient can be easily adjusted to 0.70 or less.
Examples of the organic particles include acrylic resins, styrene resins, melamine resins, polyamide resins, polyethylene waxes, fluororesins, and urethane resins. Among these, acrylic resins, styrene resins, melamine resins, and polyamide resins can be suitably used.
Examples of the metal oxide particles include ITO, ATO, zinc oxide, and magnesium oxide. Among these, ITO, ATO, and zinc oxide can be preferably used because they have conductivity and can impart an antistatic function.
Examples of inorganic particles include silica, feldspar, and silicate. Among these, silica can be preferably used.
These may be used individually by 1 type and may use multiple types together.

<Sealant material>
The sealant material 36 is preferably determined in consideration of the material of the carrier tape. For example, as the sealant material 36, polyamide, polyurethane, polyester, polystyrene, styrene thermoplastic elastomer such as styrene-butadiene-styrene block copolymer, acrylic copolymer, polyolefin such as polyethylene or polypropylene, ethylene / vinyl acetate copolymer, and the like. Polymer, ethylene / vinyl alcohol copolymer, ethylene / vinyl acetate / acrylate copolymer, ethylene / methyl (meth) acrylate copolymer, ethylene / ethyl acrylate copolymer, vinyl chloride, vinyl chloride-vinyl acetate copolymer And a mixture thereof, and a mixture thereof. These can be used alone or in combination of two or more.

(Middle layer)
The intermediate layer 40 is made of, for example, an elastic body having a shear modulus smaller than that of the base material layer 20 (specifically, polyethylene, ethylene / vinyl alcohol copolymer, styrene-based, amide-based, or ester-based thermoplastic elastomer) ). If the intermediate layer 40 made of such an elastic body is provided, the contact of the thermocompression bonding iron at the time of sealing is improved, so that heat sealing can be stably performed.
The thickness of the intermediate layer 40 is preferably 10 to 70 μm. If the thickness is less than 10 μm, the tear strength tends to be low, and if it exceeds 70 μm, the heat conduction at the time of sealing decreases, and the sealing property of the cover tape 10 to the carrier tape tends to decrease.

(Production method)
As a method for manufacturing the cover tape 10, for example, the intermediate layer 40 is formed on the base material layer 20, the sealant layer 30 is further formed on the intermediate layer 40, and slit to a predetermined width. Thereafter, for example, as shown in FIG. 2, there is a method of winding the slit cover tape 10 concentrically around the winding core 60 to obtain a wound body 50 of record winding.
Examples of the method for forming the intermediate layer 40 on the base material layer 20 include a dry lamination method and an extrusion lamination method. The extrusion lamination method is preferable because flexibility increases. As a method for forming the sealant layer 30 on the intermediate layer 40, for example, a coating liquid containing spherical particles 34 and the sealant material 36 is prepared, and the coating liquid is applied to the intermediate layer 40 and dried. A method is mentioned. Examples of the coating method for the coating liquid include gravure coating, comma coating, roll coating, and the like.
Alternatively, the intermediate layer 40 and the sealant layer 30 may be formed by coextrusion on the base material layer 20.

When the cover tape 10 is wound around a winding core to form a wound body 50 (FIG. 2), the wound body 50 is in a state where the sealant layer side surface 32 and the base material layer side surface 22 are layered. When the wound body 50 of the record-covered cover tape 10 is placed in a high-temperature environment for a long time, heat is absorbed from the environment and the cover tape 10 and the winding core 60 expand. Since the sealant layer 30 is a layer that is sealed by heating, the sealant layer 30 and the base material layer 20 tend to adhere to each other under a high temperature environment, and even after cooling, the sealant layer 30 tends not to slip. For this reason, when cooled, a part of the cover tape 10 that cannot follow the shrinkage of the adjacent cover tape 10 is distorted and becomes “smooth”, or the shrinkage of the cover tape 10 cannot follow the shrinkage of the core 60. In some cases, the winding core 60 may come off.
According to the present invention, the coefficient of static friction between the sealant layer side surface 32 and the base material layer side surface 22 is set to 0.70 or less, so that the sealant layer side surface 32 and the base material layer side surface 22 are easily slipped and expanded at a high temperature. In the contraction at the time of cooling, it is possible to follow the expansion and contraction of the adjacent cover tape 10 and the winding core 60. For this reason, the layer formation between the cover tapes 10 is disturbed, and it is difficult for “winding” to enter the wound body 50 or to loosen the degree of winding of the cover tape 10 around the winding core 60. As a result, it is possible to prevent collapse during storage / transport and when the cover tape 10 is used.

  Furthermore, by adding spherical particles 34 having an average particle diameter of 0.01 to 20 μm to the sealant layer 30, the spherical particles 34 are exposed from the sealant layer 30 to form convex portions, or the sealant material 36 is spherical. A convex portion is formed covering the surface of the particle 34. The surface of the convex portion thus formed is substantially spherical and has an appropriate size and number, so that adhesion between the sealant layer side surface 32 and the base material layer side surface 22 is prevented and the convex portion is formed on the base material layer 20. There is no strong bite. As a result, the static friction coefficient between the sealant layer side surface 32 and the base material layer side surface 22 can be set to 0.70, and the winding body 50 can be prevented from being collapsed during storage and transportation and use.

  In the above-described embodiment, the cover tape has the intermediate layer, but the present invention is not limited to this, and the intermediate layer may not be provided.

EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated concretely, it is not limited to an Example.
(Spherical particles)
The spherical particles used for the production of the cover tape are as follows.
(1) Acrylic resin particles (average particle diameter = 10 μm, CV value = 25%) In the table, described as acrylic 1. (2) Acrylic resin particles (average particle diameter = 10 μm, CV value = 45%) ... described as acrylic 2 in the table (3) acrylic resin particles (average particle diameter = 1 µm, CV value = 25%) ... described as acrylic 3 in the table (4) acrylic resin particles (average particle (Diameter = 20 μm, CV value = 45%)... Described in the table as acrylic 4 (5) acrylic resin particles (average particle diameter = 21 μm, CV value = 25%)... Described in the table as acrylic 5 (6) ATO (average particle size = 0.01 μm, CV value = 25%)... ATO1 in the table (7) ATO (average particle size = 0.02 μm, CV value = 45%) In the table, described as ATO2 (8) ATO (average particle size = 0.02 μm, CV = 46%) ... described as ATO3 in the table (9) Silica (average particle size = 10 µm, CV value = 25%) · described as silica 1 in the table (10) silica (average particle size = 20 µm) , CV value = 45%)... Described in the table as silica 2

(Examples 1 , 3 to 9, Reference Example , Comparative Examples 1 and 3)
As a base material layer, a biaxially stretched polyester film (thickness 16 μm, width 900 mm, S type, manufactured by Unitika Co., Ltd.), EL-510 (manufactured by Toyo Morton Co., Ltd.) as an anchor coating agent (AC agent) is applied and dried. Then, a base material layer film was obtained. According to the composition of Table 1, a spherical particle was added to 100 parts by mass of a sealant material (CMPS (registered trademark) V-201, manufactured by Mitsui DuPont Chemical Co., Ltd.). Then, the base layer film is coextruded so that the intermediate layer has a polyethylene resin (L-705, manufactured by Sumitomo Chemical Co., Ltd.) with a thickness of 30 μm, and the sealant layer includes spherical particles with a thickness of 20 μm. Lamination was performed to obtain a cover tape (Production Method 1). The obtained cover tape was subjected to a static friction coefficient test and a roll collapse evaluation, and the results are shown in Table 1.

(Example 10, comparative example 2)
As a base material layer, a biaxially stretched polyester film (thickness 16 μm, width 900 mm, S type, manufactured by Unitika Co., Ltd.) is coated with EL-510 (manufactured by Toyo Morton Co., Ltd.) as an AC agent, and dried. A film was obtained. According to the composition of Table 1, a coating liquid was prepared by adding spherical particles to 100 parts by mass of a sealant material (acrylic resin, LR-1065, manufactured by Mitsubishi Rayon Co., Ltd.). Then, a polyethylene resin (L-705, manufactured by Sumitomo Chemical Co., Ltd.) was extruded at a thickness of 30 μm as an intermediate layer on the surface of the base material layer film on which the AC agent was applied to obtain a laminate. The surface of the intermediate layer of the obtained laminate was subjected to corona treatment, and then the coating liquid was applied to the treated surface as a sealant layer by 10 μm and dried to obtain a cover tape having a 4 μm sealant layer (production method) 2). The obtained cover tape was subjected to a static friction coefficient test and a roll collapse evaluation, and the results are shown in Table 1.

(Static friction coefficient test)
The static friction coefficient test was performed according to JIS-K7125 “Plastic Film and Sheet Friction Coefficient Test Method”. Two test pieces obtained by cutting the cover tape into 80 mm × 20 mm were prepared and stored for 16 hours under the conditions of 23 ± 2 ° C. and 50 ± 6% RH. In addition, tribogear (HEIDON-14D, manufactured by Shinto Kagaku Co., Ltd.) was used for measurement, and the measurement was performed at a load of 100 g and a test speed of 100 mm / min.

(Rolling roll evaluation)
The cover tape was slit to 5.3 mm width × 480 m and wound to obtain a wound body. The obtained wound body was allowed to stand at 40 ° C. for 24 hours, then cooled at 25 ° C. for 12 hours, the state of the wound body was visually confirmed, and a roll collapse evaluation test was performed. The evaluation of the collapse was performed with “○” indicating that no “s”, which is the gap between the cover tapes in the wound body, was observed, and “×” indicating that even one “s” was observed. .

As shown in Table 1, in Examples 1 and 3 to 10 in which the static friction coefficient between the base material layer side surface and the sealant layer side surface of the cover tape was 0.70 or less, The occurrence of “su” was not observed between the layers of the tapes. On the other hand, in Comparative Examples 1 to 3 in which the coefficient of static friction between the base material layer side surface and the sealant layer side surface of the cover tape exceeded 0.70, occurrence of “su” was observed in the evaluation of collapse. From this, by setting the coefficient of static friction between the base material layer side surface and the sealant layer side surface of the cover tape to 0.70, the occurrence of “soot” is prevented, and storage, transportation, and use are in progress. It was found that the roll could be prevented from collapsing.

It is sectional drawing which shows an example of the cover tape of this invention. It is a perspective view which shows an example of the wound body of the cover tape of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Cover tape 20 Base material layer 22 Base material layer side surface 30 Sealant layer 32 Sealant layer side surface 34 Spherical particle 36 Sealant material 40 Intermediate layer 50 Winding body 60 Core

Claims (4)

The surface layer is a laminate in which a base material layer and a sealant layer containing a sealant material are positioned, and the sealant layer contains substantially spherical particles having an average particle diameter of 0.01 to 20 μm in 100 parts by mass of the sealant agent. The particle has 0.5 to 10 parts by mass, and the particles have a CV value represented by the following formula (1) of 45% or less, and the coefficient of static friction between the surface of the base material layer and the surface of the sealant layer is: Cover tape that is 0.70 or less.
CV value (%) = (standard deviation of particle size distribution ÷ average particle size) × 100 (1) The cover tape according to claim 1 , wherein the particles are one or more selected from the group consisting of acrylic resins, styrene resins, melamine resins, and polyamide resins. 2. The cover tape according to claim 1 , wherein the particles are made of at least one selected from the group consisting of indium tin oxide, antimony-doped tin oxide, and zinc oxide. The particles are silica, the cover tape according to claim 1.

Images