Tray or carrier tape for electronic component transportation, and manufacturing method and regeneration method therefor

Abstract

To provide: a transport tray or a carrier tape for an electronic component whose base material can be recycled and reused; and a regeneration method therefor.SOLUTION: A transport tray or carrier tape for an electronic component of the present invention includes: a base layer that is a plastic sheet; a conductive ink layer disposed on at least a side of one surface of the base layer; and an intermediate layer which is disposed between the base layer and the conductive ink layer and is configured to remove the conductive ink layer in an alkali solution. A surface resistance value on the side of the conductive ink layer is 1×103 to ×1×1013 Ω / sq.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a carrier tray or carrier tape for electronic components, and a manufacturing method and a recycling method thereof. [Background technology]

[0002] 2. Description of the Related Art In response to the demand for smaller, lighter, and more functional electronic devices incorporating electronic components, the electronic components are transported on trays or carrier tapes and incorporated into electronic device products during the manufacture of the electronic devices.

[0003] An electronic component transport tray is a tray made of synthetic resin with multiple storage compartments for storing electronic components that consist of semiconductor elements such as semiconductor chips, liquid crystal modules, and hard disk components, which are formed by vacuum molding or other methods to match the shape of the components, and the carrier tape is also used for transporting and mounting the electronic components. Electronic component transport trays are stacked in multiple trays with electronic components inserted in the storage compartments, and the trays are wound up on the carrier tape together with the electronic components for transport or storage.

[0004] With such transport trays or carrier tapes for electronic components, static electricity can be generated during transportation, storage, or other handling due to friction between the transport tray or carrier tape and the electronic components, or between the transport trays or carrier tapes themselves. This static electricity can cause problems, so it is necessary to impart conductivity to the transport trays or carrier tapes for electronic components to suppress the generation of static electricity.

[0005] In order to suppress the generation of static electricity, methods have been considered in the past, such as coating the surface of a synthetic resin sheet that has rigidity, formability, shape retention, etc., and that serves as the base material for trays or carrier tapes for transporting electronic components, with carbon nanotubes (Patent Document 1) or a conductive ink containing a conductive polymer.

[0006] Currently, conductive ink-coated transport trays and carrier tapes for electronic components are discarded after use because the conductive ink cannot be easily removed. However, there is a demand for plastic recycling as an important initiative to realize a carbon-free society and curb global warming.

[0007] Conventionally, a technique proposed for removing a printed layer from a printed plastic sheet involves providing an intermediate layer between the plastic sheet and the printed layer, made of a release ink containing a resin composition that can swell or dissolve in an alkaline solution, and treating the printed plastic sheet in an alkaline solution to release and remove the printed layer and release layer (Patent Documents 2 to 6). [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Patent No. 6656450 [Patent Document 2] Patent No. 3934292 [Patent Document 3] Patent No. 6388131 [Patent Document 4] Patent No. 6631964 [Patent Document 5] Patent No. 6928766 [Patent Document 6] Patent No. 7100750 Summary of the Invention [Problem to be solved by the invention]

[0009] However, it is necessary to provide electrical conductivity to the carrier tray or carrier tape for electronic components to suppress the generation of static electricity, and there is a problem that the conductive ink layer cannot obtain the desired electrical conductivity if an intermediate layer that allows the conductive ink layer to be removed in an alkaline solution is provided.

[0010] The present invention has been made in consideration of the above-mentioned circumstances, and an object of the present invention is to provide a transport tray or carrier tape for electronic components whose base material can be recycled and reused, as well as a manufacturing method and a regeneration method thereof. [Means for solving the problem]

[0011] Although the ink itself that can be removed with an alkaline solution is an existing technology, combining it with a conductive ink layer has not been considered so far. The reason why the conductive ink layer does not have the desired conductivity when an intermediate layer is provided is thought to be due to the unevenness of the intermediate layer and stretching due to vacuum molding, etc. Therefore, the inventors conducted extensive research and found that by adjusting the thickness of the conductive ink layer, a conductive tray that has both conductivity and releasability can be obtained, which led to the completion of the present invention. That is, the carrier tray or carrier tape for electronic components of the present invention comprises a base layer which is a plastic sheet, A conductive ink layer provided on at least one side of the base layer; and an intermediate layer provided between the base layer and the conductive ink layer, which allows the conductive ink layer to be removed in an alkaline solution. 3 ~×1×10 13 It is characterized by its Ω / □. The transport tray or carrier tape for electronic components is preferably a molded product obtained by stretching a laminate sheet of the base layer, the conductive ink layer, and the intermediate layer. In this transport tray or carrier tape for electronic components, it is preferable that the thickness of the conductive ink layer is such that when the laminated sheet of the base layer, the conductive ink layer, and the intermediate layer is stretched to a stretch ratio of 2, calculated from the ratio of the thicknesses before and after stretching, the increase in resistance value of the stretched portion is within 80 times. In the transport tray or carrier tape for electronic components, the intermediate layer preferably contains a resin composition that is swellable or soluble in an alkaline solution. The method for producing a transfer tray or carrier tape for electronic components of the present invention is characterized by including a step of stretching and molding the laminated sheet of the base layer, the conductive ink layer, and the intermediate layer. The method for recycling a carrier tray or a carrier tape for electronic components of the present invention includes a step of immersing the carrier tray or the carrier tape for electronic components in an alkaline solution to swell or dissolve the intermediate layer provided between the base layer and the conductive ink layer, and removing at least the conductive ink layer from the carrier tray or the carrier tape for electronic components; The method is characterized by including a step of recycling the base material layer from which the conductive ink layer has been removed as a molding material. Effect of the Invention

[0012] According to the present invention, by providing an intermediate layer between the conductive ink layer and the substrate layer, which allows the conductive ink layer to be removed in an alkaline solution, the tray or carrier tape for transporting electronic components can be immersed in an alkaline solution to remove the conductive ink layer and the intermediate layer, and the substrate layer can be returned to an unprinted state, which makes it possible to recycle and reuse the substrate. [Brief description of the drawings]

[0013] [Figure 1] FIG. 2 is a longitudinal sectional view showing a schematic layer structure of the carrier tray or carrier tape for electronic components of the present invention. [Diagram 2] 1 is a graph showing the relationship between the coating thickness and the resistance value for test pieces in which the coating thickness of conductive ink was changed without providing an intermediate layer (detachment ink). [Diagram 3] 1 is a graph of a followability test showing the relationship between the elongation ratio in vacuum molding and the resistance value for test pieces in which the coating thickness of conductive ink is changed. [Figure 4] 1 is a graph showing the results of a tracking test in Examples and Comparative Examples. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present invention will be described.

[0015] The transport tray or carrier tape for electronic components of the present invention has a base layer which is a plastic sheet, a conductive ink layer provided on at least one side of the base layer, and an intermediate layer provided between the base layer and the conductive ink layer, which allows the conductive ink layer to be removed in an alkaline solution. 1 is a longitudinal sectional view showing a schematic layer structure of a carrier tray or carrier tape for electronic components according to the present invention. In this example, an intermediate layer 3 is provided between a base layer 1 and a conductive ink layer 2 provided on one side of the base layer 1, and the intermediate layer 3 allows the conductive ink layer 2 to be removed in an alkaline solution. The intermediate layer 3 and the conductive ink layer 2 may be provided on both sides of the base layer 1.

[0016] The base layer is a long plastic sheet, and imparts rigidity, moldability, shape retention, etc. to the carrier tray or carrier tape for electronic components. The base layer can be made of a resin material that is moldable. As the resin material, synthetic resins, especially thermoplastic resins, are preferable. Specific examples of the resin material include polyester resins such as amorphous polyethylene terephthalate resin (A-PET), polyolefin resins such as polypropylene resin, polystyrene resin, polyamide resin, polyvinyl chloride resin, polycarbonate resin, acrylonitrile-butadiene-styrene copolymer resin (ABS resin), etc. The base layer can be blended with other components, such as known additives that are usually blended with resin materials, within the range that does not impair the effects of the present invention.

[0017] In the case of a carrier tray for electronic components, the thickness of the base layer is preferably 0.2 to 2.0 mm, more preferably 0.4 to 1.4 mm, from the standpoint of strength and moldability. In the case of a carrier tape for electronic components, the thickness of the base layer is preferably 0.1 to 1.0 mm, more preferably 0.2 to 0.4 mm, from the viewpoints of strength and formability.

[0018] The conductive ink layer is a layer formed by applying and drying a conductive ink. The conductive ink is a dispersion liquid in which a conductive material is dispersed in a liquid, and contains the conductive material and a solvent such as water or an organic solvent, and may also contain other components such as a binder resin. For example, a known conductive ink or a commercially available conductive ink can be used. Examples of the conductive material include a conductive carbon material, a conductive polymer, metal particles, and conductive oxide particles. Examples of the conductive carbon material include conductive carbon black, carbon nanotubes, graphene, graphite, and conductive carbon fibers. Examples of the conductive polymer include polythiophenes, polypyrroles, polyanilines, polyazulenes, polyindoles, polycarbazoles, polyacetylenes, polyfurans, polyparaphenylenevinylenes, polyazulenes, polyparaphenylenes, polyparaphenylenes, polyparaphenylene sulfides, polyisothianaphthenes, and polythiazyls. Examples of polythiophenes include PEDOT / PSS (poly(styrenesulfonic acid)) containing PEDOT (poly(3,4-ethylenedioxythiophene)). Examples of metals or alloys include gold, platinum, silver, copper, nickel, rhodium, palladium, magnesium, chromium, titanium, iron, and alloys thereof. Examples of conductive oxide particles include indium tin oxide (ITO), indium zinc oxide (IZO), and the like.

[0019] The thickness of the conductive ink layer is preferably such that when the laminated sheet of the substrate layer, the conductive ink layer, and the intermediate layer is stretched to a stretch ratio of 2 times, calculated from the ratio of the thicknesses before and after stretching, the resistance value increase rate of the stretched portion is within 80 times, more preferably within 50 times, and even more preferably within 20 times. Here, the laminated sheet is a laminated sheet after drying in which the intermediate layer and the conductive ink layer are provided on the substrate by printing the release ink on the substrate and printing the conductive ink on the release ink. The substrate may be a substrate of a carrier tray or carrier tape for electronic components actually manufactured, but as a standard, the resistance value increase rate may be measured using an amorphous polyethylene terephthalate resin (A-PET) or polypropylene resin (PP) having a thickness of 0.5 mm. The method of stretching when measuring the resistance value increase rate is not particularly limited, but for example, the substrate may be processed by vacuum molding.

[0020] If the thickness of the conductive ink layer is within the above range, the increase in resistance value due to stretching can be suppressed, and the resistance value does not increase significantly from the target resistance value when the conductive ink is applied to a substrate without providing an intermediate layer to form a conductive ink layer.

[0021] The thickness of the conductive ink layer is preferably thicker than usual in order to reduce the resistance value increase rate and to reduce the resistance value after stretching, but if it is too thick, it takes a long time to dry and productivity is reduced. The thickness of the conductive ink varies depending on the type, shape, size, and original conductivity of the conductive material, but it is preferably within the range of 1.5 to 3.0 times the standard thickness at which the desired resistance value is obtained by applying the ink to the substrate without providing an intermediate layer according to the type of conductive material. For example, when the conductive material is a carbon nanotube ink, the thickness of the conductive ink layer is preferably within the range of 1.5 to 3.0 times with 0.3 μm as the standard. When the conductive material is a conductive polymer ink, the thickness of the conductive ink layer is preferably within the range of 1.5 to 3.0 times with 1.0 μm as the standard.

[0022] For the intermediate layer, a release ink is used, which is known as a technique for releasing and removing a printed layer from a printed substrate layer. Patent documents 2 to 6 disclose such release inks, and their descriptions are referred to. This release ink can easily remove the primer layer printed with the release ink and the printed layer printed thereon from the substrate layer with an alkaline solution. The release ink includes both cases where the intermediate layer is peeled off from the substrate without dissolving, and where the intermediate layer is dissolved and peeled off. The ink swells or dissolves in the alkaline solution, and the conductive ink layer can be released from the substrate layer. By providing an intermediate layer of release ink on the substrate layer surface of a plastic sheet, during recycling, the intermediate layer on which the conductive ink layer is formed is peeled off from the substrate layer by the alkaline solution, and the upper conductive ink layer (ink coating) is peeled off together with the intermediate layer without being broken into small pieces, making post-processing easy. Neutralization with an alkaline solution allows the treatment liquid to reach the intermediate layer, and the intermediate layer becomes hydrophilic as a result of neutralization, or loses its adhesiveness to the base layer as a result of swelling. The intermediate layer, together with the conductive ink layer, spontaneously falls off from the base layer in a film or lump state, making post-processing such as separation of the detached material easier.

[0023] The intermediate layer contains a resin composition that can swell or dissolve in an alkaline solution. The resin composition of the intermediate layer has, for example, an acidic functional group or a hydroxyl group whose charge characteristics change depending on the pH, and by adjusting the acid value or hydroxyl value in consideration of the releasability in an alkaline solution and the adhesion to the substrate, the conductive ink layer and the substrate layer are adhered to each other while being swelled or dissolved in the alkaline solution, and are peeled off. The acidic functional group refers to a functional group that can be neutralized with potassium hydroxide when measuring the acid value, and specifically includes a carboxyl group and a sulfonic acid group, and is preferably a carboxyl group.

[0024] Examples of resin skeletons that swell or dissolve in an alkaline solution include polyester resins, polyacrylic resins, acrylic-modified polyester resins, polyurethane resins, acrylic-modified polyurethane resins, polyolefin resins, rosin resins, and styrene-maleic acid copolymer resins. These may be used alone or in combination of two or more. Acidic functional groups or hydroxyl groups are introduced into these resin skeletons by, for example, using a polymerizable monomer having an acidic functional group or a hydroxyl group, and homopolymerizing or copolymerizing the monomer. In addition, the intermediate layer may be used by mixing a low molecular weight compound having an acidic functional group with a resin that is film-forming at room temperature, or may contain a resin having an ester structure that is easily decomposed in an alkaline solution.

[0025] The intermediate layer detachment ink can be produced by dissolving and / or dispersing a resin composition that is swellable or soluble in an alkaline solution in an aqueous or solvent-based solvent, and may contain other components such as known additives as necessary.

[0026] The thickness of the intermediate layer is preferably 1.5 to 4.0 μm, and more preferably 2.0 to 3.0 μm, from the viewpoints of releasability and followability of the conductive ink.

[0027] In the carrier tray or carrier tape for electronic components of the present invention, for example, a release ink is printed on the substrate, and a conductive ink is printed on the release ink, so that an intermediate layer and a conductive ink layer can be provided on the substrate. Printing may be on either one side or both sides. There is no particular limitation on the printing method, but for example, a gravure printer, a reverse gravure printer, a comma coater, a lip coater, or the like can be used. The release ink and the conductive ink can be printed and then dried to form an intermediate layer and a conductive ink layer.

[0028] The surface resistance of the surface on which the conductive ink layer is formed is set to 1×10 in consideration of the conductivity required for the transport tray or carrier tape for electronic components and the printability of short ink drying time. 3 ~×1×10 13 Ω / □ is preferred, 1×104 ~×1×10 12 Ω / □ is more preferable, 1×10 5 ~×1×10 11 is more preferred.

[0029] The carrier tray or carrier tape for electronic components of the present invention is preferably a molded product that involves stretching of a laminated sheet of a base layer, a conductive ink layer, and an intermediate layer. The molding method involving stretching is not particularly limited, but for example, known methods such as vacuum molding, press molding, pressure molding, and vacuum pressure molding can be used. Among these, the carrier tray or carrier tape for electronic components of the present invention is preferably processed by vacuum molding.

[0030] A sheet is molded to form a number of pocket-like storage sections in accordance with the size and shape of the electronic components to be placed on the tray. Electronic components, for example, semiconductor elements are inserted into the storage sections of the tray, and the trays are stacked in multiple layers to transport to the required location, store, and pick up from the tray for use in a subsequent process.

[0031] Carrier tapes for electronic components are formed from a sheet so as to form a number of storage sections that become pockets according to the size and shape of the electronic components to be mounted. For example, electronic components having semiconductor elements as elements are inserted into the storage sections, sealed with cover tape, and then wound up on a reel, transported to a required location, stored, and picked up from the tape for use in a subsequent process.

[0032] (Method of recycling carrier trays or carrier tapes for electronic components) The carrier tray or carrier tape for electronic components of the present invention can be recycled by a method including the following steps A and B. (Step A) A step of immersing a carrier tray or a carrier tape for electronic components in an alkaline solution to swell or dissolve an intermediate layer provided between a base layer and a conductive ink layer, and removing at least the conductive ink layer from the carrier tray or the carrier tape for electronic components. (Process B) The process of reusing the base layer after removing the conductive ink layer as a molding material.

[0033] In step A, the intermediate layer of the anchor coat swells or dissolves in the alkaline solution, causing the intermediate layer and the conductive ink layer to detach from the substrate. This includes both cases where the intermediate layer detaches due to neutralization and swelling, and cases where the intermediate layer detaches due to dissolution.

[0034] Since the purpose is to obtain the substrate after the detachment as a recycled substrate, it is preferable to remove as much of the intermediate layer and the conductive ink layer as possible from the substrate. Specifically, it is preferable that at least 50% by mass or more of the intermediate layer (100% by mass) is detached in the area or thickness direction. More preferably, it is 60% by mass or more, even more preferably 80% by mass or more, and particularly preferably 90% by mass or more.

[0035] The alkaline compound used in the alkaline solution is not particularly limited, and examples thereof include sodium hydroxide, potassium hydroxide, calcium hydroxide, ammonia, barium hydroxide, and sodium carbonate. Sodium hydroxide and potassium hydroxide are preferred. The solvent of the alkaline solution is not particularly limited, but a solvent mainly composed of water is preferred. From the viewpoint of maintaining sufficient basicity to swell or dissolve the intermediate layer and to detach the base material, the alkaline solution preferably contains an alkaline compound in an amount of 0.5 to 20% by mass, more preferably 1 to 15% by mass, and even more preferably 3 to 15% by mass, of the entire solution.

[0036] The alkaline solution penetrates from the edge of the laminated sheet of the base layer, intermediate layer, and conductive ink layer, contacts the intermediate layer, and swells or dissolves it, thereby separating the base layer from the intermediate layer and the conductive ink layer. Therefore, in order to efficiently proceed with the removal process, it is preferable that the transport tray or carrier tape for electronic components is cut or crushed so that the intermediate layer is exposed on the cross section when it is immersed in the alkaline solution. In such a case, the base layer can be removed in a shorter time.

[0037] The temperature of the alkaline solution when the carrier tray or carrier tape for electronic components is immersed is preferably 25 to 120° C., more preferably 30 to 120° C., and even more preferably 30 to 80° C. The immersion time in the alkaline solution is preferably 1 minute to 24 hours, more preferably 1 minute to 12 hours, and even more preferably 1 minute to 6 hours. In order to improve the desorption efficiency, it is preferable to stir or circulate the alkaline solution.

[0038] In step B, the substrate layer from which the intermediate layer and conductive ink layer have been removed is recycled as a molding material. The intermediate layer is peeled off from the substrate layer together with the conductive ink layer, and the substrate is detached and collected, and then the substrate is washed with water to remove the alkaline aqueous solution. If necessary, a drying step may be further included. This allows a recycled substrate to be obtained.

[0039] The obtained recycled substrate can be processed into pellets by an extruder or the like and reused as recycled resin. Specifically, for example, the process includes a step of melting and regenerating the substrate layer from which the intermediate layer and the conductive ink layer have been removed. Various additives are added as necessary, and a kneader, extruder, or the like is used to mix or melt-knead the resin composition in the form of pellets, powder, granules, beads, or the like can be obtained. Furthermore, a master batch may be mixed with the recycled resin to form a molding material. The master batch is not particularly limited as long as it is compatible with the recycled resin, and various thermoplastic resins can be used. The master batch may be kneaded with known additives such as colorants such as inorganic pigments and organic pigments. The obtained molding material can be molded by, for example, injection molding, extrusion molding, blow molding, compression molding, or the like to obtain a molded body. This molding material not only has a high recycling rate, but also has moldability, and since the recycled resin is light in color, it is possible to provide molded bodies that are uniformly colored in a range of colors from light to dark, regardless of the molding method mentioned above, and it can be used for recycling transport trays or carrier tapes for electronic components, as well as other molded products. EXAMPLES

[0040] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0041] (base material) As the plastic sheet, amorphous polyethylene terephthalate resin (A-PET) or polypropylene resin (PP) having a thickness of 0.5 mm was used.

[0042] (Conductive ink) CNT ink 32g of multi-walled carbon nanotubes (NC7000 manufactured by Nanocyl) and 100g of dispersant were dropped into 2400g of a mixed solvent of pure water:isopropanol = 5:1, and dispersed for 130 minutes using an ultrasonic disperser to prepare a CNT dispersion. 1620g of a water dispersion of thermoplastic saturated polyester resin (PES RESIN A-645GH manufactured by Takamatsu Oil Co., Ltd.) was mixed with this CNT dispersion to obtain a CNT ink.

[0043] Aniline ink 9g of polymethylmethacrylate resin (PMMA, Fujifilm Wako Pure Chemical Industries, Ltd.) was dissolved in 51g of a 1:1 mixed solvent of toluene and methyl ethyl ketone to prepare a PMMA solution. 225g of ion-exchanged water and 103g of ammonium persulfate were added dropwise to a mixture of 120g of ion-exchanged water, 15g of dodecylbenzenesulfonic acid, 34g of aniline, and 3g of sulfuric acid, and the water was removed to prepare a polyaniline pigment. This polyaniline pigment was mixed with the PMMA solution and dispersed in a high-speed stirrer for 30 minutes to obtain aniline ink.

[0044] (Desorption ink) The following release inks were used: Desorption ink 1: Oil-based anchor coating agent manufactured by Toyo Ink Co., Ltd. Desorption ink 2: Water-based anchor coating agent manufactured by Toyo Ink Co., Ltd. Desorption ink 3: PES RESIN A-680 (water dispersion of thermoplastic saturated polyester resin) manufactured by Takamatsu Oil Co., Ltd.

[0045] (Preparation of test specimens) The release ink was printed on a substrate using a bar coater, and then a conductive ink was printed on top of the release ink using the bar coater to prepare a test piece.

[0046] Test Method Detachability 3g of sodium hydroxide was added to 197g of pure water, and dissolved by stirring with a magnetic stirrer to prepare a 1.5% sodium hydroxide solution as an alkaline solution. The test pieces were stirred in the alkaline solution under the following conditions, and the ink releasability was confirmed. The judgment criteria were that the color difference ΔE*ab between the raw material and the test pieces from which the ink had been removed was measured using a spectrophotometer (Nippon Denshoku Industries Co., Ltd.), and if ΔE*(ab) was less than 3, it was marked as ◯, and if it was 3 or more, it was marked as ×. <Detachment test conditions> Test piece: 2.5cm square Stirring method: Magnetic stirrer Test temperature: 70℃ Test duration: 10 minutes

[0047] Followability After vacuum molding using a cylindrical mold, the resistance and thickness of each stretched part were measured. The resistance was measured using a surface resistance measuring device ULTRA MEGOHMMETER SM 8220 (manufactured by DKK Toa Corporation), and the thickness was measured using a DIGIMATIC MICROMETER (manufactured by Mitutoyo Corporation). The stretching ratio was calculated from the ratio of the thickness before and after stretching. The criteria for judgment were as follows: a substrate with a thickness of 0.5 mm was processed by vacuum molding, and the part stretched to 0.25 mm was stretched twice; if the resistance increase rate was within 50 times after 2 times stretching, it was marked as ◯; if the resistance increase rate was between 50 times and 80 times, it was marked as △; and if the resistance increase rate exceeded 80 times, it was marked as ×.

[0048] Productivity The decision was made based on factors such as printing suitability, such as ink drying time when printing on a production machine, and cost.

[0049] Evaluation of recycled pellets After the alkali desorption test, each test piece was cut into small pieces, extruded with a single screw extruder, and quenched with water to produce pellets. The color difference ΔE*ab between the produced pellets and pellets produced from the raw roll was measured using a spectrophotometer (Nippon Denshoku Industries Co., Ltd.) to confirm whether the pellets had been regenerated to the state of the raw roll. The judgment criteria were as follows: ◯ if ΔE*(ab) was less than 3, and × if ΔE*(ab) was 3 or more.

[0050] (1) Standard coating thickness of conductive ink Using CNT ink as the conductive ink, the coating thickness of the conductive ink was changed by changing the bar coater No. 2 to No. 24 used to coat the conductive ink on the substrate, and the resistance value was measured. The results are shown in Figure 2. The resistance value decreases as the coating thickness of the conductive ink increases. The resistance value of the transport tray or carrier tape using CNT ink was 1 x 10 7 The thickness of bar coater No. 4, which provides a sufficient resistance value, was used as the standard coating thickness.

[0051] (2) Thickness of the ink applied The above-mentioned releasability test was performed by changing the coating thickness of the detachable ink 1 and 2 by changing the bar coater No. 2 to No. 24 for coating the substrate with the detachable ink. The results are shown in Table 1. If the coating thickness of the detachable ink is thin, the film stress of the detachable ink layer is weak, so some parts do not detach cleanly as a film (Table 1 shows the color difference of both the part where the ink has not been detached and the part where the ink has been detached). However, if the coating thickness is too thick, the detachable ink does not stretch during sheet molding, resulting in poor followability and inhibiting the conductivity of the carrier tray or carrier tape for electronic components. Based on the above results, the coating thickness of the detachable ink is set to a range of 1.5 to 4.0 μm, and the coating thickness of the ink in the following tests is set to 2.0 μm. [Table 1]

[0052] (3) Coating thickness of conductive ink when intermediate layer (detachable ink) is included The above-mentioned followability test was performed by changing the thickness of the conductive ink applied by using CNT ink as the conductive ink and changing the bar coater No. 4 to No. 12 to apply the conductive ink to the substrate. The results are shown in Figure 3. When the conductive ink is applied on the release ink, the followability is worse than when only the conductive ink is applied. The followability is improved by increasing the thickness of the conductive ink applied. Since the surface of the release ink applied to the substrate surface has unevenness, if the conductive ink is thin, the connection of the conductive ink is likely to be broken by the unevenness when stretched, and the conductivity is thought to decrease. On the other hand, if the conductive ink is thick, the connection of the conductive ink remains even when stretched, and it is thought that the decrease in conductivity is suppressed. However, if the thickness of the conductive ink applied is too thick, it takes a long time for the ink to dry. From these points, it has become clear that, considering the required resistance value and productivity as a carrier tray or carrier tape for electronic components, it is preferable to apply the conductive ink with a thickness within 1.5 to 3.0 times the normal thickness. Normally, bar coater No. 4 was used as the standard coating thickness, but based on the above results, bar coater No. 6 was used as the standard in the following tests.

[0053] Example 1 Desorption ink 1 was printed on a 0.5 mm thick A-PET substrate with a bar coater to a thickness of 2 μm and dried for 30 minutes at 60° C. CNT ink was printed as a conductive ink on top of the desorption ink 1 with a bar coater to a thickness of 0.3 μm and dried for 30 minutes at 60° C. to prepare a test piece.

[0054] Example 2 A test piece was prepared in the same manner as in Example 1, except that the conductive ink was changed to aniline ink and printed to a thickness of 1.0 μm.

[0055] Example 3 A test piece was prepared in the same manner as in Example 1, except that the substrate was changed to a PP substrate.

[0056] Example 4 A test piece was prepared in the same manner as in Example 1, except that the release ink was changed to release ink 2.

[0057] Example 5 A test piece was prepared in the same manner as in Example 1, except that the release ink was changed to release ink 3.

[0058] Example 6 A test piece was prepared in the same manner as in Example 1, except that the thickness of the conductive ink was changed from 0.3 μm to 0.4 μm.

[0059] Example 7 A test piece was prepared in the same manner as in Example 1, except that the thickness of the conductive ink was changed from 0.3 μm to 0.6 μm.

[0060] Comparative Example 1 A test piece was prepared in the same manner as in Example 1, except that the conductive ink was directly printed on the substrate to a thickness of 0.2 μm without printing the release ink.

[0061] Comparative Example 2 A test piece was prepared in the same manner as in Example 2, except that the conductive ink was directly printed on the substrate to a thickness of 0.67 μm without printing the release ink.

[0062] Comparative Example 3 A test piece was prepared in the same manner as in Example 1, except that the thickness of the conductive ink was changed from 0.3 μm to 0.2 μm.

[0063] Comparative Example 4 Test pieces were prepared in the same manner as in Example 1, except that the thickness of the conductive ink was changed from 0.3 μm to 1.2 μm.

[0064] The test pieces of the above-mentioned Examples and Comparative Examples were subjected to tests of releasability and tracking ability, and productivity was confirmed. The results are shown in Table 2. In addition, the color difference values ​​measured using a spectrophotometer in the releasability tests in the Examples and Comparative Examples are shown in Table 3. Furthermore, as a result of evaluation of the recycled pellets, the color difference values ​​measured using a spectrophotometer are shown in Table 4.

[0065] [Table 2]

[0066] [Table 3]

[0067] [Table 4]

[0068] In Comparative Examples 1 and 2, the followability and productivity were good, but the ink releasability was not. In addition, in the evaluation of the recycled pellets, the ink was not released, so the color difference was larger than that of the recycled A-PET. In Comparative Example 3, the followability and productivity were good, but the followability was poor. On the other hand, in Examples 1 and 2, the followability and productivity were good, and the followability was also good by increasing the thickness of the conductive ink to 1.5 times the standard. In addition, in the evaluation of the recycled pellets, the color difference with the recycled A-PET was small, so it is considered that recycling can be performed without problems. In Examples 3 to 5, the followability, followability, and printability were also good. In Example 6, the followability was even better than Example 1 because the thickness of the conductive ink was 2.0 times the standard, and in Example 7, the followability was even better than Example 6 because the thickness of the conductive ink was 3.0 times the standard. In Comparative Example 4, the releasability was good, but the tracking ability did not change significantly even though the thickness of the conductive ink was twice that of Example 7. In addition, because the conductive ink was too thick, the ink took a long time to dry, and there was a concern that cracks would occur, resulting in poor productivity. [Explanation of symbols]

[0069] 1 Base material layer 2 Conductive ink layer 3. Middle tier

Claims

1. A base layer which is a plastic sheet; A conductive ink layer provided on at least one side of the base layer; and an intermediate layer provided between the substrate layer and the conductive ink layer, which allows the conductive ink layer to be removed in an alkaline solution. 3 ~×1×10 13 A carrier tray or carrier tape for electronic components having a resistance of Ω / □.

2. 2. The transport tray or carrier tape for electronic parts according to claim 1, which is a molded product obtained by stretching a laminate sheet of the base material layer, the conductive ink layer, and the intermediate layer.

3. 2. A transport tray or carrier tape for electronic components as described in claim 1, wherein the thickness of the conductive ink layer is such that when a laminated sheet of a base layer, a conductive ink layer, and an intermediate layer is stretched to a stretch ratio of 2, calculated from the ratio of the thicknesses before and after stretching, the resistance value increase rate of the stretched portion is within 80 times.

4. 2. The transport tray or carrier tape for electronic parts according to claim 1, wherein the intermediate layer contains a resin composition that is swellable or soluble in an alkaline solution.

5. The method for producing a transport tray or carrier tape for electronic components according to any one of claims 1 to 5, comprising a step of stretching and molding a laminated sheet of the base material layer, the conductive ink layer, and the intermediate layer.

6. A process of immersing the electronic component transport tray or carrier tape according to any one of claims 1 to 5 in an alkaline solution to swell or dissolve the intermediate layer provided between the base layer and the conductive ink layer, and removing at least the conductive ink layer from the electronic component transport tray or carrier tape; and A method for recycling a transport tray or carrier tape for electronic components, comprising a step of recycling the base material layer from which the conductive ink layer has been removed as a molding material.

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