JP7365321B2 - Carrier tape mount for chip-shaped electronic components - Google Patents

Description

The present invention relates to a carrier tape mount for chip-shaped electronic components. Specifically, the present invention relates to a carrier tape mount for chip-shaped electronic components that has low density and flexibility and is less likely to generate paper dust when forming a recessed or perforated loading portion for loading chip-shaped electronic components.

Conventionally, chip-shaped electronic components have been automatically attached to printed circuit boards in order to automatically produce various electronic devices. In the process of automatically mounting chip-shaped electronic components, chip-shaped electronic components are supplied one by one onto a printed wiring board using a chip component mounting machine or the like, and are automatically mounted onto the printed wiring board. In this automatic mounting process, in order to easily handle the chip-shaped electronic components, a taping package in which each chip-shaped electronic component is wrapped in a tape-shaped carrier is used.

The taping package has concave or perforated loading parts (hereinafter sometimes simply referred to as "loading parts") for loading chip-shaped electronic components formed at regular intervals on a carrier tape mount, and the loading parts It is formed by loading a predetermined chip-shaped electronic component into a container and then enclosing it with a cover tape. Note that the loading section is generally provided in a rectangular shape and is sometimes called a press pocket, cavity, or the like. The loading portion is formed using a mold (see, for example, Patent Document 1 or 2).

The taping package loaded with chip-shaped electronic components is conveyed in a reel shape, and the cover tape is continuously peeled off by an automatic machine that attaches chip-shaped electronic components, and the chip-shaped electronic components are sequentially taken out from the carrier tape mount. It is automatically attached to a predetermined position on the printed wiring board.

The carrier tape mounts used here are broadly classified into those made of plastic and those made of paper. Paper is considered desirable in terms of manufacturing cost, non-static properties, and ease of disposal after use. As carrier tape mounts made of paper, those made of single-layer or multi-layer paperboard are known (see, for example, Patent Documents 3 to 5).

In paper carrier tape mounts such as those disclosed in Patent Documents 3 to 5, the shape of the loading portion is required to be formed accurately. Here, a mold is used to form the loading section. However, the molds wear out, which increases paper dust, and it is necessary to polish or renew the molds. Therefore, there are problems such as significantly deteriorating operability and increasing costs. In order to minimize mold wear and suppress the generation of paper dust, a carrier tape mount that is more flexible and strong is required.

Japanese Patent Application Publication No. 2002-211507 Japanese Patent Application Publication No. 10-218281 Japanese Patent Application Publication No. 09-188385 Japanese Patent Application Publication No. 2005-313946 Japanese Patent Application Publication No. 2008-230651

In view of such operational problems, the present disclosure proposes a carrier tape mount for chip-shaped electronic components. More specifically, it is an object of the present invention to provide a carrier tape mount for chip-shaped electronic components that has low density and flexibility, and is less likely to generate paper dust when forming a recessed or perforated loading portion for loading chip-shaped electronic components. purpose.

Other objects and effects of the present invention will be easily understood by those skilled in the art by referring to the following description.

In order to solve the above problems, the carrier tape mount for chip-shaped electronic components according to the present invention is made of multilayer paper having three or more layers of base paper mainly composed of pulp, and 1) has a density of 0.88 g/cm ³ or less. and
2) Contains 5% by mass or more of softwood bleached kraft pulp (NBKP) in the pulp,
3) Contains a rosin-based sizing agent, the content of which is 0.15% or less based on 100 parts by mass of pulp,
4) The straight chain fatty acid content is 1600 ppm or less. With this configuration, despite having a low density, the carrier tape mount for chip-shaped electronic components is unlikely to generate paper dust when forming a recessed or perforated loading section for loading chip-shaped electronic components. can do.

Among the layers of the base paper, the layer placed on one surface is referred to as the surface layer, the layer placed on the other surface is referred to as the back layer, and the layer placed between the surface layer and the back layer is referred to as the intermediate layer. In this case, it is preferable that 5% by mass or more of the pulp contained in the intermediate layer is NBKP. By setting the content to 5% by mass or more, the strength in the accelerated load test becomes high, and even if NBKP, which easily comes off, is blended, the content of the rosin-based sizing agent is below the desired content and the content of straight chain fatty acids is below the desired content. For example, paper dust is less likely to be generated when forming a recessed or perforated loading portion for loading chip-shaped electronic components.

It is preferable that the straight chain fatty acid has a carbon number selected from the group consisting of 24, 26, and 28, and has a content of 1200 ppm or less. Within this range, paper dust is less likely to be generated when forming a recessed or perforated loading portion for loading chip-shaped electronic components.

According to the present disclosure, there is provided a carrier tape mount for chip-shaped electronic components that is less likely to generate paper dust when forming a recessed or perforated loading portion for loading chip-shaped electronic components, despite its low density. I can do it.

Next, the present invention will be described in detail by showing embodiments, but the present invention should not be interpreted as being limited to these descriptions. The embodiments may be modified in various ways as long as the effects of the present invention are achieved.

The carrier tape mount of the present invention is required to have a low density because the mount needs to be soft in order to prevent delamination, but it also needs to be resistant to accelerated loads. In the present invention, an accelerated load test using a roll is employed as one of the indicators serving as a standard for such resistance. In the accelerated load test, the material is wrapped in a single layer around a roll with a small radius, and the roll is moved back and forth repeatedly to observe delamination and measure the strength against delamination. In order to prevent delamination between layers, the mount needs to be soft, so lower density is required. On the other hand, since various strengths tend to decrease when the density is lowered, NBKP is blended to compensate for this. However, with a multilayer carrier tape mount, when forming the loading part, distortion occurs between the layers, and when NBKP is mixed, which is difficult to fibril and has a large fiber length, it is pulled out without being cut, generating paper dust. cause it to happen. Therefore, the present invention requires a carrier tape mount that has sufficient strength against accelerated load tests and is less likely to generate paper waste, despite its low density. Accelerated load testing is performed by moving the carrier tape mount wrapped around a roll back and forth to squeeze (handle) the space between the roll and the mount, that is, by creating friction due to acceleration, until the gap between the layers opens. The number of times is the number of times, and the number of times is an index of resistance to delamination. Note that the greater the number of times, the stronger the resistance to delamination.

The carrier tape mount for chip-shaped electronic components according to the present embodiment is a multilayer paper-made chip-shaped electronic component having three or more layers of base paper arranged in the order of a surface layer, an intermediate layer, and a back layer mainly composed of pulp. In the carrier tape mount for
1) The density is 0.88 g/cm ³ or less,
2) Contains 5% by mass or more of softwood bleached kraft pulp (NBKP) in the pulp,
3) Contains a rosin-based sizing agent, the content of which is 0.15% or less based on 100 parts by mass of pulp,
4) Straight chain fatty acid content is 1600 ppm or less. As used herein, ppm is parts per million by mass.

The carrier tape mount for chip-shaped electronic components of this embodiment has a base paper whose main component is pulp. Here, the main component refers to the component having the highest content on a mass basis among the components constituting the base paper. In this embodiment, pulp is preferably 80% by mass or more, more preferably 90% by mass or more, and even more preferably 100% by mass among the components constituting the base paper. As the raw material pulp used for the base paper, softwood bleached kraft pulp (NBKP) and hardwood bleached kraft pulp (LBKP) are preferable. Chemical pulps such as hardwood unbleached kraft pulp (LUKP), softwood unbleached kraft pulp (NUKP), mechanical pulps such as ground wood pulp (GP) and thermomechanical pulp (TMP), and waste paper pulps such as deinked pulp contain lignin and foreign substances. It is preferable to minimize or not use it when using it. It is preferable that the pulp has bleached hardwood kraft pulp (LBKP) as a main component, and the bleached hardwood kraft pulp (LBKP) accounts for 75% by mass or more, preferably 80% by mass or more, or 85% by mass or more of the total pulp. do it. For example, in the total pulp, hardwood bleached kraft pulp (LBKP) may be 85 to 95% by mass, and softwood bleached kraft pulp (NBKP) may be 5 to 15% by mass. In the present invention, since the mount needs to be soft, a lower density is required. On the other hand, since various strengths tend to decrease when the density is lowered, NBKP is blended to compensate for this. It is preferable to mix NBKP in an amount of 5% by mass or more in the pulp in each layer. By setting the content to 5% by mass or more, the strength against accelerated load tests will be high, and even if NBKP, which easily comes off from the paper, is blended, the content of the rosin-based sizing agent will be less than the desired content, and the content of the straight chain fatty acids will be the desired content. If it is below, paper dust will be less likely to be generated when forming a recessed or perforated loading portion for loading chip-shaped electronic components. Adding NBKP to the intermediate layer is more effective in improving strength in accelerated load tests. Furthermore, it is preferable that 5 parts by mass or more of the resin be added to the pulp in the intermediate layer. For example, it is preferable that NBKP is not blended in the surface layer and the back layer, but is blended in the intermediate layer in an amount of 5 parts by mass or more, for example 5 to 25 mass %, based on the pulp. When NBKP is blended only in the intermediate layer, there is an advantage that the adhesive force of the tape is less likely to be inhibited by NBKP when used as a mount.

The wood chips used to make LBKP are mainly acacia wood and eucalyptus wood. Acacia wood includes Acacia mangium, Acacia auricarformis, Acacia catechu, Acacia decalance, Acacia holoselicia, Acacia leptocarpa, Acacia maydeniai, Acacia melanthi, Acacia melanoxylon, Acacia neriphora, Acacia sylivest. Squirrel, Acacia peregrinalis, etc., and hybrids thereof can be mentioned, and it is preferable to use at least one tree species among these. Acacia wood has a low specific gravity, is easy to obtain, and is inexpensive, while containing a large amount of straight chain fatty acids, especially straight chain fatty acids with a carbon number selected from the group consisting of 24, 26, and 28. In order to reduce the amount of straight chain fatty acids, it is preferable not to incorporate too much acacia wood. In the case of Japan, when importing from relatively nearby countries such as Southeast Asia such as Vietnam or Australia, the amount of straight chain fatty acids tends to be high because the seasoning period is short due to the short distance. As a result, there are large differences depending on the production area, so it is important to control the amount of straight chain fatty acids in the produced carrier tape mount for chip-shaped electronic components.

Examples of eucalyptus wood include Eucalyptus camaldrensis, Eucalyptus deglupta, Eucalyptus globulus, Eucalyptus grandis, Eucalyptus maculata, Eucalyptus punctata, Eucalyptus sarigna, Eucalyptus telenicornis, Eucalyptus europhylla, Acacia auracocarpa, or Acacia classicala. etc. and their hybrids. Since eucalyptus wood contains a small amount of straight chain fatty acids whose carbon number is selected from the group consisting of 24, 26, and 28 carbon atoms, it is preferable to blend a large amount of eucalyptus wood in order to reduce the amount of straight chain fatty acids. In the carrier tape mount of the present invention, the content of straight chain fatty acids must be 1600 ppm or less, but the ratio of acacia wood and eucalyptus wood, the production area, etc. may be adjusted appropriately, and the processing process of the pulp raw material may be adjusted as appropriate. By this, the straight chain fatty acid content can be adjusted. For example, the mass ratio of acacia wood and eucalyptus wood may be 10:90 to 55:45, preferably 20:80 to 40:60.

Coniferous materials for making NBKP are not particularly limited, but spruce or fir trees, fir trees, pine trees, cedar trees, and the like are preferably used. In NBKP obtained from these tree species, the amount of straight chain fatty acids having a carbon number selected from the group consisting of 24, 26, and 28 is small, for example, 400 ppm or less.

If there is a large amount of straight chain fatty acids, the bonds between fibers will be inhibited and the fibers will become slippery, making it easier for NBKP to be pulled out. Therefore, in the carrier tape mount of the present invention, the content of straight chain fatty acids is 1600 ppm or less, preferably 1300 ppm or less. Although there are various straight chain fatty acids, the straight chain fatty acids with carbon numbers of 24, 26 and 28, which are contained in large quantities in acacia, have the greatest influence, and it is preferable to reduce these. For example, the content of the straight chain fatty acids is preferably 1200 ppm or less, more preferably 1000 ppm or less. Furthermore, if there is a large amount of straight chain fatty acids, penetration of the size press liquid is inhibited and the paper tends to become uneven, which may make it difficult to impart strength using paper strength agents such as starches and polyvinyl alcohol contained in the liquid.

The raw material pulp is made into pulp slurry having an appropriate degree of beating using a disintegrator and a beater. In the present invention, it is preferable that the CSF is 300 to 800 ml according to the Canadian standard freeness (JIS P 8121:1995 pulp freeness test method). More preferably 350 to 650 ml of CSF, still more preferably 500 to 580 ml of CSF.

Pulp slurry adjusted to an appropriate degree of beating is used as a raw material slurry, and paper is made using a paper machine to form the base paper of the carrier tape mount. A known paper machine can be used as the paper machine. That is, paper can be made using a Fourdrinier paper machine, a cylinder paper machine, a hybrid former, a gap former, or the like. The structure of the base paper is preferably multilayer paper having three or more layers. When the paper is made of three or more layers, starch or an aqueous polyacrylamide solution may be sprayed between each layer for the purpose of improving the interlayer strength.

A rosin-based sizing agent is added to the raw material slurry in an amount of 0.15% by mass or less. For example, 0.03 to 0.15% by mass of a rosin-based sizing agent is added to 100 parts by mass of pulp. NBKP is more difficult to pull out if no sizing agent is added, but if no sizing agent is added, all the sizing press liquid will be absorbed into the base paper and will not remain on the surface, resulting in insufficient surface strength and fuzzing that will be a problem when removing the top tape. coming out. If it exceeds 0.15% by mass, slipping occurs and the NBKP is easily pulled out and becomes paper dust. Sizing agents used for internal addition include alkyl ketene dimer (AKD) and alkenyl succinic anhydride (ASA), but AKD has a friction coefficient that is too low and causes slippage during processing, which is a problem, while ASA has an adverse effect on the rise in size. Because the size is not developed before the size press, all the size press liquid is absorbed by the base paper and does not remain on the surface, resulting in a problem of insufficient surface strength and fluffing that causes the top tape to peel off. Examples of rosin-based sizing agents include rosin sizing agents, reinforced rosin sizing agents, and rosin emulsion sizing agents. In particular, an emulsion sizing agent that exhibits sizing properties in a small amount is preferable, and depending on the pH range in which it is used, there are acidic, weakly acidic, or neutral emulsion sizing agents, but it is preferable to use it in the recommended pH range. It is preferable to use a neutral rosin emulsion sizing agent because the carrier tape mount for chip-shaped electronic components is manufactured in a neutral region to prevent chip corrosion.

Paper-making additives such as fillers, paper strength agents, retention improvers, coloring dyes, and coloring pigments may be added to the raw material slurry as appropriate within a range that does not impair the intended effects of the present invention. In order to reduce wear of the carrier tape, the amount of filler, particularly inorganic filler, in the carrier tape mount is preferably 1% by mass or less, more preferably 0.5% by mass or less. In this specification, the inorganic filler includes ash derived from the raw material pulp and mixed in unintentionally. The lower limit of the content of the inorganic filler contained in the carrier tape mount is not particularly limited, but may be 0.1% by mass or more, taking into consideration this unintentionally mixed ash content. Furthermore, a surface paper strength enhancer can be applied to the surface of the base paper, if necessary. The method of coating the base paper is not limited, and coating machines such as a two-roll size press, a gate roll size press, and a metering size press can be used to coat the base paper. Among these, it is preferable to use a two-roll size press from the viewpoint of manufacturing efficiency, processing suitability, improvement of surface strength, and improvement of paper layer strength. The coating amount of the surface paper strength enhancer is preferably in the range of 0.5 to 5 g/m ² in terms of solid content per both sides of the base paper, and more preferably in the range of 1 to 3.5 g/m ² .

In this embodiment, the base paper after drying may be smoothed if necessary. The smoothing method is not particularly limited, and a machine calender, soft calender, super calender, etc. can be used.

Although the thickness of the base paper varies depending on the size of the chip-shaped electronic component to be loaded, it is preferably 400 to 1200 μm, more preferably 800 to 1100 μm. Further, the basis weight of the entire base paper is preferably 160 to 1000 g/m ² , more preferably 600 to 1000 g/m ² . The density of the base paper is 0.88 cm ³ /g or less, preferably 0.85 cm ³ /g or less. Setting it to 0.88 cm ³ /g or less makes the paper soft and increases the strength in accelerated load tests, and even if the density is low, the content of the rosin-based sizing agent is below the desired content and the straight chain fatty acid is the desired content. If the content is less than or equal to 1, paper dust will be less likely to be generated when forming a recessed or perforated loading portion for loading chip-shaped electronic components.

Further, the carrier tape mount may contain various known papermaking additives. Examples of papermaking additives include sizing agents, internal paper strength enhancers such as wet paper strength enhancers, bulking agents, retention improvers, freeness improvers, colored dyes, colored pigments, optical brighteners, and fluorescent agents. There are decolorizing agents, pitch control agents, etc. Furthermore, water-soluble polymers such as starch, polyvinyl alcohol, and polyacrylamide may be coated. For example, after making a 5-layer paper with a surface layer (first layer), middle layer (2nd to 4th layer), and back layer (5th layer) as a base paper, 2 to 10% by mass of oxidized starch and It is preferable to apply a mixed size liquid containing 2 to 10% by mass of polyvinyl alcohol to both sides of the base paper. This is because the strength of the paper is enhanced.

The carrier tape mount for chip-shaped electronic components of this embodiment has loading sections for loading chip-shaped electronic components formed at regular intervals, and after loading the chip-shaped electronic components into the loading sections, they are sealed with a cover tape. , used as a carrier tape for chip-shaped electronic components. The loading portion may be either a bottomed recess formed by embossing or a through hole formed by punching. When using a through hole, a bottom tape is attached to one surface of the carrier tape mount to close one of the through holes to form a loading section.

Next, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples. Further, "parts" and "%" in the examples indicate "parts by mass" and "% by mass", respectively, unless otherwise specified. Note that the number of parts added is a value in terms of solid content.

<Example 1>
A 5-layer paper consisting of a surface layer (1st layer), an intermediate layer (2nd to 4th layer), and a back layer (5th layer) was made as a base paper as follows. A pulp slurry consisting of 90 parts of LBKP (mass ratio of acacia wood: eucalyptus wood is 30:70) and 10 parts of NBKP was beaten and adjusted to 525 ml of Canadian Standard Freeness (CSF), and 0.2 parts of sulfate and cationic starch (product) were added. Name: Neotac #30T/manufactured by Nihon Shokuhin Kako Co., Ltd.) 0.7 parts, amphoteric polyacrylamide (product name: Hermide RB234/manufactured by Harima Kasei Co., Ltd.) 0.3 parts, rosin emulsion sizing agent (product name: CC-1404/ 0.1 part of Seiko PMC Co., Ltd.) was added, and the raw material slurry was made into five layers of wet paper consisting of a surface layer, an intermediate layer, and a back layer using a cylinder paper machine to obtain a base paper. After that, the water was reduced in a press part, and after drying, oxidized starch (SK-20/manufactured by Nippon Corn Starch Co., Ltd.) 5.3% and polyvinyl alcohol (Gosenal T-350/manufactured by Nippon Gosei Kagaku Kogyo Co., Ltd.) were added using a two-roll size press. ) A 4.0% mixed size liquid was applied to the base paper at a rate of 3 g/ ^m2 per both sides, dried with a cylinder dryer to a moisture content of 9%, and smoothed using a multi-stage calender. The desired carrier tape mount for chip-shaped electronic components was obtained. The basis weight of each layer was 160 g/m ² for the surface layer, 3 layers of 160 g/m ² for the middle layer, and 160 g/m ² for the back layer, and the basis weight of the entire base paper was 800 g/m ² . The ash content in the carrier tape mount for chip-shaped electronic components was 0.4% by mass.

<Example 2>
A carrier tape mount for chip-shaped electronic components was obtained in the same manner as in Example 1 except that 0.1 part of the rosin emulsion sizing agent was changed to 0.05 part.

<Example 3>
A carrier tape mount for a chip-shaped electronic component was obtained in the same manner as in Example 1 except that 0.1 part of the rosin emulsion sizing agent was changed to 0.15 part.

<Example 4>
By adjusting the wood chips during pulp production, we changed the mass ratio of acacia wood to eucalyptus wood in LBKP to 15:85, and changed the amount of linear fatty acids (carbon numbers 24, 26, 28 ) A carrier tape mount for chip-shaped electronic components was obtained in the same manner as in Example 1 except that the concentration was changed from 1000 ppm to 700 ppm.

<Example 5>
We adjusted the wood chips during pulp production, changed the mass ratio of acacia wood to eucalyptus wood in LBKP to 40:60, and changed the amount of linear fatty acids (carbon numbers 24, 26, 28 ) A carrier tape mount for chip-shaped electronic components was obtained in the same manner as in Example 1 except that the concentration was changed from 1000 ppm to 1200 pm.

<Example 6>
A carrier tape mount for chip-shaped electronic components was obtained in the same manner as in Example 1, except that the pulp composition of the surface layer and back layer was changed from 90 parts of LBKP and 10 parts of NBKP to 100 parts of LBKP.

<Example 7>
The chip-shaped electronic component was manufactured in the same manner as in Example 1, except that the pulp composition of the surface layer and back layer was changed from 90 parts of LBKP and 10 parts of NBKP to 100 parts of LBKP, and the pulp composition of the middle layer was changed from 90 parts of LBKP and 10 parts of NBKP to 80 parts of LBKP and 20 parts of NBKP. A carrier tape mount was obtained.

<Comparative example 1>
A carrier tape mount for chip-shaped electronic components was obtained in the same manner as in Example 1 except that 0.1 part of the rosin emulsion sizing agent was changed to 0.2 part.

<Comparative example 2>
By adjusting the wood chips during pulp production, we changed the mass ratio of acacia wood to eucalyptus wood in LBKP to 60:40, and changed the amount of linear fatty acids (carbon numbers 24, 26, 28) in the carrier tape mount for chip-shaped electronic components. ) A carrier tape mount for chip-shaped electronic components was obtained in the same manner as in Example 1 except that the concentration was changed from 1000 ppm to 1500 pm.

<Paper powder evaluation>
The carrier tape mount for chip-shaped electronic components was slit into a tape shape with a width of 8 mm, and in accordance with JIS C 0806-3: 2014 "Packaging of automatic mounting components - Part 3: Packaging of surface mount components with continuous tape", Using a press pocket type loading part molding machine (TWA-6507, manufactured by Tokyo Wells Co., Ltd.), a concave loading part measuring 0.7 mm in the width direction x 0.4 mm in the flow direction was molded for 10 million shots at 2 mm intervals. Evaluation was made based on the amount of paper powder that fell at the exit of the molding process. The evaluation criteria are as follows.
◎: The amount of paper powder is 0 to 0.5 g, which is good and passed (practical level).
○: Paper powder amount is 0.5 to 1.0 g, passing (practical level).
△: Amount of paper powder is 1.0 to 2.0 g, lower limit of acceptance (lower practical level).
×: The amount of paper powder was 3.0 g, the wear was large, and it was rejected (practical unsuitable level).

<Accelerated load test>
A carrier tape mount for chip-shaped electronic components is slit into a tape shape of 8 mm width x 1800 mm, and handled by applying a load of 1580 g and winding it around a roll with a diameter of φ20 mm. Evaluation was made based on the number of times the film was handled until the distance between the layers became 5 mm. The evaluation criteria are as follows.
◎: No peeling even after handling 200 times or more. (Practical level)
○: Peeling occurred after 150 to 200 times. (Practical level)
△: Peeling occurred after 100 to 150 times. (lower practical level)
×: Peeling occurred less than 100 times. (Unpractical level)

<Determination of fatty acid amount>
The pulp obtained by disintegrating and redrying the carrier tape mount for chip-shaped electronic components was methylated with tetramethylammonium hydrate (TMAH) and subjected to GCMS. The analysis conditions were ICP590°C pyrofoil, heating for 15 seconds, and analysis using a gas chromatograph mass spectrometer GCMS-QP2010 Ultra (manufactured by Shimadzu Corporation). Each standard substance was determined in advance from the peak areas of tetracosanoic acid (C24) with a retention time of 24.32 minutes, hexacosanoic acid (C26) with a retention time of 25.73 minutes, and octacosanoic acid (C28) with a retention time of 27.07 minutes. It was quantified using the calibration curve. Straight chain fatty acids with other carbon numbers were similarly quantified from the corresponding retention times.

As shown in Table 1, the carrier tape mounts for chip-shaped electronic components obtained in Examples 1 to 7 are less likely to generate paper dust when forming a concave or perforated loading section for loading chip-shaped electronic components. It was available for use. On the other hand, in the carrier tape mount for chip-shaped electronic components obtained in Comparative Example 1, since the blended amount of the rosin-based sizing agent was large, NBKP fibers fell off and a large amount of paper dust was generated. Since the carrier tape mount for chip-shaped electronic components obtained in Comparative Example 2 contained a large amount of straight chain fatty acids, NBKP fibers fell off and a large amount of paper dust was generated.

Claims (4)

In a carrier tape mount for chip-shaped electronic components made of multilayer paper having three or more layers of base paper arranged in the order of a surface layer mainly composed of pulp, an intermediate layer, and a back layer,
1) The density is 0.88 g/cm ³ or less,
2) Contains 5% by mass or more of softwood bleached kraft pulp (NBKP) in the pulp,
3) Contains a rosin-based sizing agent, the content of which is 0.15% or less based on 100 parts by mass of pulp,
4) A carrier tape mount for chip-shaped electronic components, characterized by having a straight chain fatty acid content of 1600 ppm or less. The carrier tape mount for chip-shaped electronic components according to claim 1, wherein 5% by mass or more of the pulp contained in the intermediate layer is NBKP. The chip-shaped electron according to claim 1 or 2, wherein the straight chain fatty acid has a carbon number selected from the group consisting of 24, 26, and 28, and has a content of 1200 ppm or less. Carrier tape mount for parts. In the total pulp, hardwood bleached kraft pulp (LBKP) is 85 to 95% by mass, softwood bleached kraft pulp (NBKP) is 5 to 15% by mass, and as LBKP, acacia wood and eucalyptus wood are mixed at a mass ratio of 10: The carrier tape mount for chip-shaped electronic components according to any one of claims 1 to 3, which is used at a ratio of 90 to 55:45.