JP5553539B2 - Embossed carrier tape and manufacturing method thereof - Google Patents

Description

  The present invention relates to an embossed carrier tape for electronic components and a method for producing the carrier tape.

Conventionally, as carrier tapes for mounting electronic components on electronic devices, embossed sheets are made of thermoplastic resin such as vinyl chloride resin, styrene resin, polyethylene terephthalate resin, and polycarbonate resin. Carrier tape is used.
Such an embossed carrier tape requires measures for preventing static electricity damage to electronic components. For example, when used for electronic components that require high antistatic properties such as ICs and LSIs, A sheet made of a resin composition containing a conductive filler such as carbon black in a plastic resin, or a generally opaque sheet in which a conductive paint or the like is applied to the surface of the resin sheet has been used.

On the other hand, for the embossed carrier tape that stores electronic components that are less likely to be damaged by electrostatic failure, such as connectors, the details of the electronic components in the contents are checked visually or with an inspection machine. In addition, since it is advantageous in terms of detecting characters written on the parts, conventionally, a transparent embossed carrier tape based on a thermoplastic resin having a relatively good transparency among the resins described above has been used. Used, the demand is increasing.
Furthermore, since these electronic components are being miniaturized, this type of transparent type carrier tape has a small thickness and excellent shape accuracy and buckling strength in addition to the transparency described above. It has been required to have an embossed portion (also referred to as an electronic component storage pocket or a cavity).

As a sheet for such a transparent embossed carrier tape, for example, as a styrene resin sheet, a sheet obtained by mixing a general-purpose polystyrene resin and a styrene-butadiene block copolymer (see Patent Document 1 or 2), styrene A sheet made of a rubber-modified styrene polymer containing a monomer unit and a (meth) acrylic acid ester monomer unit is known (see Patent Document 3 or 4).
Examples of methods for forming these sheets include press molding, vacuum forming, pressure forming, rotary vacuum forming, etc. In any of the forming methods, as described above, any of transparency, shape accuracy, and buckling strength can be used. It was difficult to obtain an excellent fine embossed part.

JP 2002-332392 A JP 2003-055526 A Japanese Patent Laid-Open No. 10-279755 JP 2003-253069 A

 An object of the present invention is to provide an embossed carrier tape having an embossed portion having good transparency and excellent shape accuracy and buckling strength, and a method for producing the same.

 In the method for producing an embossed carrier tape according to the present invention, (a) a step of slitting a sheet formed by biaxial stretching of a styrene resin composition into a tape shape, and (b) slitting by a rotating cylindrical heater. A step of winding the tape and partially heating only a portion where the embossed portion of the tape is formed; and (c) winding the tape heated by a rotating cylindrical molding die and embossing the portion by rotary vacuum forming. Forming the step.

 According to one aspect of the present invention, in the manufacturing method, in steps (b) and (c), the embossed portion of the tape is formed so that the embossed portion is formed in a partially heated portion of the tape. A cylindrical heater in which a partial heating part for heating the part to be heated is arranged on the outer periphery of the cylinder, and an embossed molding part for forming an embossed part by vacuum-sucking the tape in the direction of the molding die The cylindrical molding die arranged in the part rotates in synchronization.

 According to another aspect of the present invention, in the manufacturing method, a tape made of a biaxially stretched sheet having a sheet thickness of 0.15 to 0.5 mm is heated to 110 to 180 ° C. having a shape corresponding to an embossed portion. It heats by making it contact for 0.5 to 5.0 second with the cylindrical heater which has the heating part made. Moreover, the area of the heating part pressed against the tape is 90 to 120% with respect to the area of the part where the embossed part is formed.

 Moreover, according to one aspect of the present invention, in the manufacturing method, the orientation relaxation stress value measured according to ASTM D1504 of the biaxially stretched sheet is 0.2 to 0.8 MPa. Further, the styrene-based resin composition comprises 7 to 79.5% by mass of the polystyrene resin (A), 0.5 to 3% by mass of the high-impact polystyrene resin (B), and the styrene-conjugated diene block copolymer. 20-90 mass% of unification | combination (C) is contained. The styrene-conjugated diene block copolymer (C) is a copolymer containing 70 to 90% by mass of styrene and 10 to 30% by mass of conjugated diene.

 Further, according to the present invention, a sheet formed by biaxially stretching a styrene-based resin composition is slit into a tape shape, and the slit tape is wound by a rotating cylindrical heater to form an embossed portion of the tape. An embossed carrier tape is provided in which only a portion to be heated is partially heated, and then the tape heated by a rotating cylindrical molding die is wound and an embossed portion is formed by rotary vacuum forming.

 According to an aspect of the present invention, the embossed carrier tape is partially heated to heat a portion where the embossed portion of the tape is formed so that the embossed portion is formed in the partially heated portion of the tape. Cylindrical molding in which the embossed part for forming the embossed part by vacuum-sucking the tape in the direction of the mold and the embossed part is arranged on the cylindrical outer peripheral part. The mold rotates synchronously.

 Moreover, according to one aspect of the present invention, the embossed carrier tape is a tape made of a biaxially stretched sheet having a sheet thickness of 0.15 to 0.5 mm, and having a shape corresponding to an embossed portion at 110 to 180 ° C. It heats by making it contact for 0.5 to 5.0 second with the cylindrical heater which has the heated heating part. Moreover, according to 1 aspect of this invention, the area of a heating part is 90 to 120% with respect to the area of the part in which an embossing part is formed.

 Moreover, according to one aspect of the present invention, the orientation relaxation stress value measured according to ASTM D-1504 of the biaxially stretched sheet is 0.2 to 0.8 MPa. Further, the styrene-based resin composition comprises 7 to 79.5% by mass of the polystyrene resin (A), 0.5 to 3% by mass of the high-impact polystyrene resin (B), and the styrene-conjugated diene block copolymer. 20-90 mass% of unification | combination (C) is contained. The styrene-conjugated diene block copolymer (C) is a copolymer containing 70 to 90% by mass of styrene and 10 to 30% by mass of conjugated diene.

 According to the present invention, it is possible to provide an embossed carrier tape having an embossed portion with excellent transparency and excellent shape accuracy and buckling strength, and a method for producing the same.

It is the schematic for demonstrating the manufacturing method of the embossed carrier tape which concerns on this invention. It is the schematic for demonstrating the manufacturing method of the embossed carrier tape which concerns on this invention.

The embossed carrier tape according to an embodiment of the present invention is obtained by biaxially stretching a styrene resin composition into a sheet, and further slitting the sheet into a tape shape to form an embossed portion.
Here, the styrene resin means a homopolymer or copolymer of a styrene monomer, a general type polystyrene resin (hereinafter referred to as “GPPS resin”) having a styrene unit as a main component, and a high impact. It refers to various resins such as polystyrene resin (hereinafter referred to as “HIPS resin”), styrene-conjugated diene block copolymer, styrene- (meth) acrylate copolymer, and one or more mixtures thereof.

 In one embodiment, GPPS and HIPS are particularly used among the styrene resins as a raw material for the styrene resin for producing the sheet, and in some cases, a styrene-conjugated diene block copolymer is used as an optional component resin. A resin comprising a coalescence is used in combination.

When the example of a resin composition is given, GPPS resin (A) 7-79.5 mass%, HIPS resin (B) 0.5-3 mass%, and styrene-conjugated diene block copolymer (C) 20- 90% by mass.
Thus, in a representative embodiment, the embossed carrier tape comprises GPPS resin (A) 7-79.5 mass%, HIPS resin (B) 0.5-3 mass%, and a styrene-conjugated diene block copolymer ( C) Manufactured using a resin composition containing 20 to 90% by mass as a raw material.

 In the above, the GPPS resin (A) is a resin basically composed of styrene units, and is not particularly limited. However, in order to maintain the strength and transparency of the embossed carrier tape, its weight average molecular weight is used. Is, for example, 200,000 to 400,000, preferably 220,000 to 350,000, particularly preferably 220,000 to 260,000 in terms of polystyrene by gel permeation chromatography (GPC).

Moreover, HIPS (B) is a resin generally called “high impact polystyrene resin” as described above, and includes a resin obtained by graft polymerization of styrene in the presence of a rubber component such as diene rubber.
From the viewpoint of transparency and strength, the rubber content is preferably 4 to 10% by mass when the HIPS is 100% by mass, the rubber particle diameter is preferably 0.5 to 4 μm, and the resin fluidity is 5 g / 10 min or more. Those having excellent fluidity are preferred. More preferably, it is 5-10 g / 10min.
The rubber particle diameter means a volume-based average particle diameter, and the fluidity is a value measured according to JIS K7210.

 The styrene-conjugated diene block copolymer (C) is an optional resin component as described above, and a polymer block mainly composed of a styrene monomer and a heavy polymer mainly composed of a conjugated diene monomer in its structure. A polymer containing a combined block.

Styrene monomers include styrene, o-methylstyrene, p-methylstyrene, p-tert-butylstyrene, 1,3-dimethylstyrene, α-methylstyrene, vinylnaphthalene, vinylanthracene, 1,1-diphenyl There are ethylene and the like, and among them, styrene is preferable. One or more styrenic monomers can be used. The conjugated diene monomer is a compound having a conjugated double bond in its structure, for example, 1,3-butadiene (butadiene), 2-methyl-1,3-butadiene (isoprene), 2,3-dimethyl. There are -1,3-butadiene, 1,3-pentadiene, 1,3-hexadiene, 2-methylpentadiene, etc., among which butadiene and isoprene are preferable. One type or two or more types of conjugated diene monomers can be used.
The styrene-conjugated diene block copolymer can be used alone or in combination of two or more, and a commercially available product can be used as it is. Particularly preferred is a styrene-butadiene block copolymer.

Further, as the block structure of the styrene-conjugated diene block copolymer (C), styrene-conjugated diene block copolymers having various block structures can be adopted as long as the transparency and workability of the embossed carrier tape are not impaired. The embossed carrier tape has good transparency, strength, chip control in the slitting process, punching process, punching process, etc. of the sheet, so that the styrene content is 70 to 90% by mass and the butadiene content is 10 to 10. Examples thereof include 30% by mass and a copolymer having a styrene block part with a molecular weight of 10,000 to 130,000.
Here, if the molecular weight of a styrene block part is 10,000 or more, the transparency of an embossed carrier tape will fall and the external appearance in a molded article will not be impaired. Moreover, if the molecular weight of a styrene block part is 130,000 or less, the fluidity | liquidity in an extrusion molding process is favorable, it is not necessary to raise extrusion temperature to high temperature, and a high moldability can be obtained. Furthermore, since an extrusion process at a high temperature is not necessary, an embossed carrier tape having a low stretching temperature and a preferable strength can be obtained.

In the present invention, the molecular weight of the styrene block part means the ozonolysis of the block copolymer [Y. TANAKA, et al. , RUBBER CHEMISTRY AND TECHNOLGY, 59, 16 (1986)] In the GPC measurement of the obtained vinyl aromatic hydrocarbon polymer component (using an ultraviolet spectroscopic detector set at a wavelength of 254 nm as a detector), each peak Is obtained from a calibration curve prepared using standard polystyrene and styrene oligomer.
Here, in the block copolymer including a plurality of styrene block parts having different molecular weights, the molecular weight of the plurality of styrene block parts is obtained for each block. In this case, any styrene block portion may have a molecular weight of 10,000 to 130,000, but it is preferable that all styrene block portions have a molecular weight of 10,000 to 130,000.

Therefore, the biaxially stretched styrene resin sheet is a HIPS (B) containing 7 to 79.5 mass% of GPPS (A) and 4 to 10 mass% of a rubber component among styrene resins as a resin raw material. A styrene resin composition containing 0.5 to 3% by mass and 20 to 90% by mass of a styrene-conjugated diene block copolymer (C) having a molecular weight of 10,000 to 130,000 in a styrene block part is used.
In the above, if the content of GPPS (A) is 7% by mass or more, the tensile elastic modulus of the sheet is high, and sufficient buckling strength of the embossed part can be obtained when formed into a carrier tape. On the other hand, as described later, since containing 0.5 mass% of HIPS (B) is important in the biaxially stretched sheet of styrene resin, the styrene-conjugated diene block copolymer (C) is used. When 20% by mass is contained, the maximum content of GPPS (A) is 79.5% by mass.
The content of HIPS (B) in the resin raw material is preferably at least 0.5% by mass from the viewpoint of the slipperiness of the surface of the embossed carrier tape, and at most 3% by mass from the viewpoint of transparency and strength. preferable. In particular, from the viewpoint of obtaining good transparency, 0.5 to 2% by mass is preferable.

On the other hand, the styrene-conjugated diene block copolymer (C) is an optional resin component and may not be contained. However, when GPPS (A) and HIPS (B) are reduced, the styrene-conjugated diene block copolymer (C) should be contained up to 90% by mass. Can do.
And from a viewpoint of satisfying all the above-mentioned problems of the present invention, a styrene resin having 20 to 90% by mass of the styrene-conjugated diene block copolymer (C) is preferable, and more preferably 40 to 90% by mass. Correspondingly, the GPPS (A) content is preferably 7 to 79.5 mass%, more preferably 7 to 59.5 mass%.
By setting it as such a range, the punching process performed when this sheet | seat is shape | molded on a carrier tape, and the cutting powder generate | occur | produced when this sheet | seat is slit in tape shape can be suppressed to a low level.

 The resin composition has various additives such as stabilizers (phosphorus-based, sulfur-based or hindered phenol-based antioxidants, ultraviolet absorbers, heat absorbers, etc., as long as the object of the present invention is not impaired. Stabilizers, etc.), plasticizers (mineral oil, etc.), antistatic agents, lubricants (stearic acid, fatty acid esters, etc.), mold release agents and the like can be added. Furthermore, inorganic particles (calcium phosphate, barium sulfate, talc, zeolite, silica, etc.) can also be used.

 The biaxially stretched styrene resin sheet can be produced from the resin composition by a conventional method. For example, in one embodiment, the raw resin composition is melt-kneaded (for example, kneaded at a temperature of 170 to 240 ° C.) and extruded from a die (particularly a T die) by an extruder, and then, for example, 85 to 135 ° C. The film can be formed by sequential or simultaneous biaxial stretching at a stretching ratio of 1.5 to 5 times, preferably 1.5 to 4 times, and more preferably 2 to 3 times in the biaxial direction.

If the draw ratio is 1.5 times or more, the strength of the embossed carrier tape, particularly toughness is good, and if it is 5 times or less, the uneven thickness of the container formed by a thermoforming process such as vacuum forming / pressure forming. Can be suppressed.
Therefore, it is preferable to set the biaxially stretched sheet to be stretched almost uniformly over the entire sheet while suppressing the stretching ratio to 5 times or less. As a sequential biaxial stretching method, for example, a raw sheet extruded by using a T die or a calendar is stretched at a magnification of 1.5 to 4 times in a uniaxial direction in a heating state of 90 to 135 ° C., and then And a method of stretching at a magnification of 1.5 to 4 times in a direction perpendicular to the stretching direction in a heated state of 90 to 135 ° C.

 The orientation relaxation stress of the biaxially stretched sheet for carrier tape obtained as described above varies depending on the composition of the styrenic resin composition used, the stretching temperature, the stretching ratio, etc., and these conditions are adjusted. By doing this, a sheet having a predetermined orientation relaxation stress (shrinkage stress) can be obtained.

That is, in the biaxially stretched sheet for carrier tape according to one embodiment of the present invention, the orientation relaxation stress (shrinkage stress at 130 ° C.) measured in accordance with ASTM D-1504 after adjusting these conditions. Is 0.2 to 0.8 MPa, preferably 0.3 to 0.6 MPa.
If the orientation relaxation stress is 0.2 MPa or more, sufficient transparency can be obtained, and if it is 0.8 MPa or less, it can be easily formed into a carrier tape.

 In addition, the thickness of the biaxially stretched sheet for the carrier tape obtained as described above, in the rotary vacuum forming of the present invention, from the viewpoint of the transparency, strength, formability, chip control and burr suppression effect of the sheet, It is the range of 0.15-0.5 mm, Preferably, it is 0.16-0.4 mm, More preferably, it is 0.18-0.3 mm.

 An embossed carrier tape manufacturing method according to an embodiment of the present invention includes (a) a step of slitting a sheet formed by stretching a styrene resin composition into a tape shape, and (b) a rotating cylindrical heater. Winding the slit tape, partially heating only the part where the embossed portion of the tape is formed, and (c) winding the heated tape with a rotating cylindrical mold, and by rotary vacuum forming Forming an embossed portion.

 As shown in FIG. 1, an embossed portion is formed by heating a tape 1 slit in a biaxially stretched sheet with a cylindrical heater 2 and then performing rotary vacuum molding with a cylindrical molding die 3. .

In the cylindrical heater 2, a partial heating unit 4 is disposed along the outer periphery of the cylinder, and when the heater 2 rotates, the tape 1 is wound up, and the tape 1 is partially heated, A highly accurate embossed carrier tape 5 can be formed.
The cylindrical molding die 3 winds up the tape partially heated by the heater 2 and vacuum-sucks it by the embossing molding unit 5 to form an embossing part on the tape.

The tape 1 made of a biaxially stretched sheet is continuously fed into the heater 2 and the molding die 3. The tape feeding structure may be based on winding by a reel or the like, or may be conveyed by feeding holes provided on both sides or one side in the tape longitudinal direction, for example.
At this time, the embossing part 5 comes to be located in the part heated partially of the tape by the rotation synchronizer 6.

The area where the partial heating unit 4 of the heater 2 is in contact with the tape depends on the size of the embossed part, but is substantially the same shape as the opening surface of the embossed part, and is in the range of 90 to 120% of the embossed opening area. Moreover, it is preferable that the contact surface with the tape of the partial heating part 4 is provided in the curved surface shape which draws a plane or the concentric circle with the heater 2. FIG. Within this range, an embossed carrier tape having an embossed portion with excellent shape accuracy and buckling strength can be obtained.
The area where the partial heating unit 4 comes into contact with the tape is preferably 95 to 118%, more preferably 98 to 115% of the embossed opening area. If it is this range, a highly accurate process will be attained.

 In the embossed part forming step, as shown in FIG. 1, the inside of the embossed molded part 5 of the molding die 3 (inside of the recessed mold) is evacuated to draw the heated portion of the tape into the recessed mold, An embossed part is formed.

Further, as shown in FIG. 2, the heated portion of the tape is surrounded by the vacuum around the embossed portion 5 by vacuum-sucking the tape through the vacuum holes provided around the convex embossed portion 5 of the molding die 3. The embossed portion may be formed by shaping.
In addition, you may pass through a cooling process after formation of the embossing part by rotary vacuum forming.

 The embossed carrier tape of the present invention is formed by slitting the biaxially stretched sheet for the carrier tape into a narrow tape shape, and partially forming the embossed portion of the tape at a predetermined temperature and a predetermined time. By carrying out rotary vacuum forming after heating, it is possible to form an embossed portion that houses small electronic components that are continuous in the length direction of the tape.

 In general, rotary vacuum forming has the big feature that there is no cumulative error of continuous cavities and sprockets because the same forming is repeated every rotation by rotating the rotating drum, and embossed carrier tape that requires high accuracy is required. Although it is suitable for molding, the biaxially stretched styrene resin sheet used in the present invention has a tendency to heat shrink when thermoformed as described above, and thus requires high precision like a carrier tape. It was not used for molding.

 However, by heating only the part where the embossed part of the embossed carrier tape is formed, it is possible to perform the highly accurate molding required for the carrier tape. Here, the part where the embossed part is formed corresponds to the opening of the embossed part of the embossed carrier tape formed by vacuum forming.

 The heater used for heating has a cylindrical shape, and has a partial heating part (protrusion part) in a shape substantially similar to the opening of the embossed part of the embossed carrier tape on the circumferential part thereof. The surface in contact with the tape is provided in a planar shape or a curved shape that draws a concentric circle with the heater 2.

By partially heating a tape made of a biaxially stretched sheet with a heater having such a partial heating unit, it is possible to perform highly accurate molding required for a carrier tape.
When the entire surface of the tape is heated by a heater that does not have such a partial heating section, a tape made of a biaxially stretched styrene resin sheet tends to thermally shrink. It becomes difficult.

The partial heating is preferably performed in a predetermined area so as to include a portion where the embossed portion is formed. Therefore, if the partial heating part has a shape similar to the shape of the opening, it is preferable that the area is 90 to 120% when the area formed by the opening is 100%.
If the area of the said partial heating part is 90% or more, it is enough as a heating range required for shaping | molding, and an embossing part is shape | molded in the shape which is calculated | required. Moreover, if the area of the said partial heating part is 120% or less, the above heat shrinks will be suppressed and the highly accurate shaping | molding requested | required of a carrier tape will be attained.
Moreover, the area of the said partial heating part becomes like this. Preferably it is an area of 95-118% with respect to the area which the said opening part shape comprises, More preferably, it is an area of 98-115%. By setting it in such a range, it is possible to perform molding with higher accuracy required for the carrier tape.

The heating by the heater having the partial heating unit is preferably adjusted to a predetermined heating temperature and time with respect to the thickness of the biaxially stretched sheet. Specifically, it is preferable that a heater heated to 110 to 180 ° C. is brought into contact with the sheet for 0.5 to 5.0 seconds and heated.
If the heating by the heater is 110 ° C. or more, it becomes easy to form the tape because it has sufficient flexibility for rotary vacuum forming, and if it is 180 ° C. or less, the tape can be welded to the heater. Can be prevented.

 The heating time for contact with the tape varies depending on the thickness of the biaxially stretched sheet and the heating temperature. Generally, the heating time needs to be longer as the sheet thickness is thicker, and the heating time needs to be longer as the heating temperature is lower. It is necessary to adjust while observing the molding state. The contact heating time to the tape can be set by adjusting the tape feed speed, that is, the drum rotation speed.

 If the heating time of the tape is 0.5 seconds or more, a sufficient amount of heat for rotary vacuum forming can be given in the thickness direction of the tape, giving the tape sufficient flexibility for rotary vacuum forming, The embossed part can be formed with high accuracy. Moreover, if heating time is 5 second or less, the heating by the radiant heat from a heater to parts other than a partial heating part can be suppressed, and thermal contraction can be suppressed.

 In the rotary vacuum forming process, the molding die is cylindrical, and has an embossed molding part for forming an embossed part on the tape on the circumferential part. The embossed portion has a substantially concave female shape (FIG. 1) and a substantially concave shape toward the rotation axis (center) direction of the cylindrical molding die. There is a male mold (FIG. 2).

The tape partially heated by the heater is wound around the circumferential part of the molding die, and the embossed molding part is brought into a vacuum state, so that in the female mold, the vacuum provided in the substantially concave mold part. Since the inside of the substantially concave mold portion is depressurized by the holes, the tape is drawn into the embossed molded portion to form the embossed portion.
Further, in the male mold, since the pressure around the substantially convex part is reduced by the vacuum holes provided around the substantially convex part, the tape is drawn to the substantially convex part to form the embossed part.

 The female mold is suitable for forming a deep emboss. On the other hand, the male mold is not suitable for forming a deep emboss, but has a feature that the dimensional accuracy of the embossed inner surface (side on which electronic components are stored) can be obtained with high accuracy. Therefore, the male mold is preferably used for embossing for storing electronic parts having a thickness of about 1 mm or less, and the female mold is preferably used for embossing for storing larger electronic parts.

 After the embossed part is formed, the tape partially heated by the temperature-controlled mold is cooled, and when the tape is peeled from the mold, the shape of the formed embossed part can be maintained. it can.

 In order to maintain the shape of the embossed part of the mold and to improve the temperature control accuracy of the mold, a material having a high thermal conductivity is used. For example, the material of the mold is aluminum, copper, iron, stainless steel. However, it is preferable to use a metal such as brass, as long as it can maintain the shape of the embossed portion of the mold and has a thermal conductivity for improving the temperature control accuracy of the mold. .

 When the tape on which the embossed portion is formed is peeled from the mold, a peeling jig that assists in peeling can be used. In this case, for example, a resin peeling jig that does not damage the mold and the tape is preferably used, but this is not a limitation. Also, the shape of the peeling jig may be a substantially wedge shape, for example, and the tape can be gradually peeled from the mold, but this is not a limitation.

 Further, for the purpose of assisting the emboss formation, the roller can also be applied in contact with the circumferential portion other than the embossed molded portion. In this case, the size and number of rollers are not limited, and the material of the rollers is not particularly limited as long as the tape is not damaged. The temperature of the roller can also be adjusted. The temperature control temperature of the roller is the same as the temperature control temperature of the mold.

 In addition, the cylindrical heating by which the partial heating part for heating the part in which the embossed part of a tape is formed is arrange | positioned in the cylindrical outer peripheral part so that an embossed part is formed in the part heated partially of the tape It is preferable that an embossing part for forming an embossed part by vacuum-sucking the tape in the direction of the molding die is synchronously rotated with a cylindrical molding die arranged on the outer peripheral part of the cylinder.

There are no particular restrictions on the method of synchronization, but a method of synchronizing using a gear, a method of synchronizing using a timing belt, and a signal obtained from a sensor (such as a rotary encoder) that detects the rotation provided in the mold. Any method can be used such as a method of controlling the rotation of the heater based on the above.
Further, the diameter of the molding die and the diameter of the heater are not particularly limited as long as they are a combination of diameters that can be synchronized.

Regarding the arrangement of the molding die and the heater, the sheet heated by the heater is not cooled to a temperature at which rotary vacuum molding is impossible until the sheet is separated from the heater and is vacuum-formed by contacting the molding die. As close as possible.
If this is not possible, pass the heat-insulated sheet through a tube surrounded by heat insulating material or remove a far-infrared heater so that the tape is not cooled until the heated sheet leaves the heater and contacts the mold. It is necessary to devise such as irradiation.

Further, after the heating of the tape by the heater is completed, rotary vacuum molding is performed quickly by the molding die, and the temperature of the molding die is preferably in the range of 40 ° C to 100 ° C.
If the temperature of the molding die is 40 ° C. or higher, the temperature of the tape does not decrease during rotary vacuum forming, and sufficient flexibility is given to the tape for rotary vacuum forming. Further, if the temperature of the molding die is 100 ° C. or less, after the vacuum vacuum forming sheet is taken out from the molding die, the post-shrinkage of the tape, including the embossed portion, can be suppressed, which is required for the carrier tape. Accurate moldability is improved.

Since the embossed carrier tape of the present invention is manufactured from a biaxially stretched styrene resin, the embossed carrier tape has high transparency so that it can be confirmed also from examples described later. Therefore, the difference in transparency due to the thickness difference between the molded part and the non-molded part in the packaging container can be reduced, and the visibility of the contents can be improved.
In addition, since the embossed carrier tape of the present invention has a predetermined sheet thickness and orientation relaxation stress, it can be thinned, and at the time of post-processing such as sheet slitting process, punching of molded products, punching processing, etc. The production of swarf (resin powder) can be greatly suppressed.

The biaxially stretched sheet may be a single layer or a plurality of layers.
For example, when obtaining a biaxially stretched sheet having a plurality of layers, the resin composition used for each constituent layer is formed by a plurality of extruders, and the obtained sheet is manufactured by a heat lamination method in which the sheets are heated and laminated to be integrated. Alternatively, the resin composition for each constituent layer may be manufactured by a method of co-extrusion using a general-purpose die with a feed block, a multi-manifold die, or the like. The co-extrusion method is preferable because a thin surface layer can be obtained and is excellent in mass productivity. The biaxially stretched laminated sheet of the present invention can also be obtained by biaxially stretching the thus laminated sheet by the above method.

 When an electronic component that is easily destroyed by static electricity, such as an IC, is stored, it is desirable to apply an antistatic treatment to the surface of the carrier tape. The antistatic treatment can be performed, for example, by applying an antistatic agent to the surface of the carrier tape sheet.

 The carrier tape sheet can be wound around a roll by applying a surface treatment agent such as a release agent or an antistatic agent to obtain a drying step. Before applying the surface treatment agent, it is preferable to perform a corona treatment or the like in order to enhance the suitability of the surface treatment agent. In addition, as described above, an antistatic agent can be added to the resin composition to carry out an antistatic treatment.

 The electronic component housed in the carrier tape of the present invention is not particularly limited. For example, IC, LED (light emitting diode), resistor, liquid crystal, capacitor, transistor, piezoelectric element register, filter, crystal oscillator, crystal resonator, There are diodes, connectors, switches, volumes, relays, inductors, etc. The format of the IC is not particularly limited. For example, there are SOP, HEMT, SQFP, BGA, CSP, SOJ, QFP, PLCC and the like.

 The carrier tape and the manufacturing method thereof according to the present invention have been described with reference to the embodiment, but the present invention is not limited to these.

 Examples and Comparative Examples are shown below, but the present invention is not limited to these Examples.

 In the following examples, comparative examples, and experimental examples, the following resins 1 to 6 were used as raw materials as styrenic resins. Here, the resin 1 is a GPPS resin (A), the resin 2 is a HIPS resin (B), the resins 3 to 5 are resins containing a styrene-conjugated diene block copolymer (C), and the resin 6 is a (meth) acrylic acid ester. It is a resin containing a rubber-modified styrenic polymer containing a monomer unit.

Resin 1 GPPS resin with a weight average molecular weight of 240,000 (Toyostyrene GP HRM61 manufactured by Toyo Styrene Co., Ltd.)
Resin 2 .. HIPS resin (Toyostyrene HI H370 manufactured by Toyo Styrene Co., Ltd.) having a styrene / rubber mass ratio of 95/5, a rubber particle size of 2.9 μm, and a fluidity of 7.0 g / 10 min.
Resin 3 .. Resin containing a styrene / butadiene block copolymer having a styrene / butadiene mass ratio of 85/15 and a styrene block molecular weight of 24,000 and 125,000 (Clurelen 850L manufactured by Denki Kagaku Kogyo Co., Ltd.)
Resin 4 .. Resin containing styrene / butadiene block copolymer having a styrene / butadiene mass ratio of 75/25 and styrene block molecular weights of 48,000 and 76,000 (Clurelen 730L manufactured by Denki Kagaku Kogyo Co., Ltd.)
Resin 5 .. Resin containing a styrene / butadiene block copolymer having a styrene / butadiene mass ratio of 76/24 and styrene block molecular weights of 15,000 and 71,000 (Clurelen 210M, manufactured by Denki Kagaku Kogyo Co., Ltd.)
Resin 6 .. Styrene monomer unit and (meth) acrylic acid ester having a mass ratio of styrene / butadiene / methyl methacrylate / n-butyl acrylate of 50.5 / 6.0 / 36.5 / 7.0 Including a rubber-modified styrenic polymer containing a monomer unit

[Examples 1 to 8]
Resin 1 is used as the GPPS resin (A), and resin 2 is used as the HIPS resin (B), and the resin containing the styrene-butadiene block copolymer (C) is a resin 3 having a different styrene / butadiene mass ratio and molecular weight of the styrene block part. ~ 5 were selected and mixed at the compounding ratio shown in Table 1 to prepare various resin compositions.

 Next, each resin composition was melt-kneaded with an extruder and extruded from a T-die to obtain an unstretched sheet. Next, this unstretched sheet was stretched 2.3 times in the longitudinal direction in a heated state at 90 to 135 ° C. by a longitudinal stretching machine, and then in the transverse direction in a heated state at 90 to 135 ° C. using a lateral stretching machine. The biaxially stretched sheet according to Examples 1 to 8 was obtained by stretching 2.3 times.

 Subsequently, the orientation relaxation stress, haze, tensile elastic modulus, sheet impact, and folding strength of the obtained sheet were measured by the measurement method described later.

 Further, the obtained biaxially stretched sheet was slit into a tape shape having a width of 16 mm. Next, the tape is supplied to a company-made rotary vacuum molding machine equipped with a cylindrical heater having a partial heating section and a cylindrical molding die having an embossed molding section, and heat molding is performed under the molding conditions shown in Table 1. After that, a sprocket hole was punched out, and an embossed carrier tape provided with an embossed portion of 3 mm in length (longitudinal direction of tape) × 2 mm in width (in the same width direction) × 1.5 mm in depth and a sprocket hole was prepared.

Here, the heater and the embossed molded part are arranged at equal intervals around the cylindrical outer peripheral part so that the embossed part is formed on the outer peripheral part of the cylinder. The mold was placed in a synchronized manner and rotated.
While evaluating the moldability and buckling strength of these embossed carrier tapes according to the evaluation method described later, the state of generation of chips in the sprocket hole portion, the heat resistance of the molded product, and the like were examined. The results are also shown in Table 1.

[Example 9]
In the same manner as in Example 1, an unstretched sheet having the same sheet thickness and comprising a resin composition having the same resin composition, resin blending ratio, and sheet thickness as in Example 1 was prepared.
Next, this is stretched 1.5 times in the longitudinal direction in a heated state at 90 to 135 ° C. using a longitudinal stretching machine, and then 1.5 times in the transverse direction in a heated state at 90 to 135 ° C. using a transverse stretching machine. The biaxially stretched sheet according to Example 9 was obtained by stretching.
Next, various physical properties of the obtained sheet were measured by the measurement methods described later. Moreover, it shape | molded to the embossed carrier tape by the method similar to Examples 1-8, and investigated the moldability. The results are also shown in Table 1.

[Example 10]
In the same manner as in Example 1, an unstretched sheet having the same sheet thickness and comprising a resin composition having the same resin composition, resin blending ratio, and sheet thickness as in Example 1 was prepared.
Next, this is stretched 4.5 times in the longitudinal direction in a heated state at 90 to 135 ° C. with a longitudinal stretching machine, and then 4.5 times in the transverse direction in a heated state at 90 to 135 ° C. with a transverse stretching machine. The biaxially stretched sheet according to Example 10 was obtained by stretching.
Next, various physical properties of the obtained sheet were measured by the measurement methods described later. Moreover, it shape | molded to the embossed carrier tape by the method similar to Examples 1-8, and investigated the moldability. The results are also shown in Table 1.

[Comparative Example 1]
In the same manner as in Example 1, an unstretched sheet having the same sheet thickness and comprising a resin composition having the same resin composition and resin blending ratio as in Example 1 was prepared. Next, this was stretched in the longitudinal direction by a longitudinal stretching machine and then in the lateral direction by a lateral stretching machine in the same manner as in Example 1 to obtain a biaxially stretched sheet according to Comparative Example 1. Next, various physical properties of the obtained sheet were measured by the measurement methods described later.
Moreover, it shape | molded to the embossed carrier tape by the method similar to Example 1, and investigated the moldability etc. The results are also shown in Table 2.
However, in Comparative Example 1, the portion corresponding to the embossed portion was not partially heated, but was heated by a method of heating the entire tape with a heater having a shape in which the partial heating portion in the heater was eliminated. .

[Comparative Example 2]
In the same manner as in Example 1, an unstretched sheet having the same resin composition, resin blending ratio, and sheet thickness as in Example 1 was prepared, and a sheet according to Comparative Example 2 was obtained. Next, various physical properties of the obtained sheet were measured by the measurement methods described later.
Moreover, it shape | molded to the embossed carrier tape by the method similar to Example 1, and investigated the moldability etc. The results are also shown in Table 2. In Comparative Example 2, the sheet was not stretched.

[Comparative Example 3]
In the same manner as in Example 1, an unstretched sheet having the same sheet thickness and comprising a resin composition having the same resin composition and resin blending ratio as in Example 1 was prepared. Next, this was stretched in the longitudinal direction by a longitudinal stretching machine and then in the lateral direction by a lateral stretching machine in the same manner as in Example 1 to obtain a biaxially stretched sheet according to Comparative Example 3. Next, various physical properties of the obtained sheet were measured by the measurement methods described later.
In Comparative Example 3, the sheet was formed by a normal pressure forming machine. In this compressed air molding machine, after heating the entire tape with an infrared heater, a plurality of concave embossed molding parts are sent to a molding die part arranged on a flat surface, and have a dent so as to cover the embossed molding part. After being held by the upper die, pressurized air is supplied from a pressurized air supply hole having an opening in the recess of the upper die, and the embossed portion is formed. The results of examining the moldability and the like are also shown in Table 2.

Various performances of the carrier tape sheet and the embossed carrier tape were evaluated by the following methods.
1. Orientation relaxation stress MD and TD orientation relaxation stresses of the sheet were measured according to ASTM D-1504. MD is the sheet winding direction, and TD is the sheet width direction.
2. Haze The haze of the sheet was measured using a haze meter NDH2000 manufactured by Nippon Denshoku Industries Co., Ltd. according to JIS K 7105.
3. Tensile modulus The tensile modulus of the sheet was measured according to JIS K 7127 using a tensile testing machine.
4). Sheet Impact Tester A sheet impact strength was measured using a tip impactor (R10) using a film impact tester manufactured by Sangyo Sangyo Co., Ltd.
5. Folding strength Using a folding strength measuring machine, the number of reciprocal bendings until the sheet specimen was cut was measured according to JIS P8115.
6). State of chips generated during drilling The sprocket hole was drilled by the sprocket hole drilling section attached to our company's rotary vacuum forming machine, and the sprocket hole was observed with a measuring microscope (Mitutoyo). . The ratio of the area of the chip occupied in the sprocket hole was calculated by setting the state without the chip as 0%.
7). Evaluation of Formability Each carrier tape sheet of each Example and Comparative Example was slit to 16 mm width, and longitudinal (tape longitudinal direction) 3 mm × horizontal (tape width direction) 2 mm × depth by the above-described rotary vacuum forming machine. An embossed carrier tape having an embossed portion with a thickness of 1.5 mm was molded, and the formability of the sheet was visually observed. The evaluation of formability is a three-step evaluation with ○ having good formability, △ that has low formability but can be embossed, and x that cannot be embossed due to punching, sheet shrinkage, etc. went.
8). Buckling strength of molded product The embossed carrier tape obtained by the above molding was compressed from the bottom surface of the embossed portion using a tensile tester, and the buckling strength at which the embossed portion buckled was measured.
9. Heat resistance of the molded product Measure the amount of change (21 mm) in length of 21 sprocket holes drilled at 4 mm intervals before and after storing in an oven at 60 ° C. for 24 hours. did. If the amount of change was not 0.3 mm, it was marked as ◯, and if it was larger than 0.3 mm, it was marked as x.

 As can be seen from the results in the above table, the sheet thickness and orientation are produced from a resin composition containing a predetermined amount of GPPS resin (A), HIPS resin (B), and optionally styrene-butadiene block copolymer (C). Embossing obtained by partial vacuum heating of biaxially stretched sheets according to Examples 1 to 10 whose relaxation stress value is controlled within a desired range while controlling the heating temperature, heating time, etc. within the desired range, and then rotary vacuum forming Carrier tape is excellent in haze (transparency), tensile elastic modulus, sheet impact strength, folding strength, and excellent in formability and buckling strength of the embossed part of the molded product. Is also suppressed.

[Other experimental examples]
Next, another experimental example is shown. In this experimental example, for the biaxially stretched sheet of Example 1, the resin composition, the sheet thickness, the heating temperature for partial heating of the tape, the contact time during heating for partial heating of the tape, and the orientation relaxation stress value were changed. It was. For Experimental Example 10, a resin composition was prepared using only the resin 6.

 From the above table, it can be seen that the properties of the resulting carrier tape are affected by the sheet thickness and various conditions when the tape is partially heated.

DESCRIPTION OF SYMBOLS 1 Tape 2 Heater 3 Molding die 4 Partial heating part 5 Embossing molding part 6 Rotation synchronizer 7 Embossed carrier tape

Claims (10)

(A) A styrenic resin composition is biaxially stretched, the orientation relaxation stress value measured according to ASTM D-1504 is 0.2 to 0.8 MPa, and the thickness is 0.15 to 0 Slitting a single-layer sheet having a thickness of 5 mm into a tape shape;
(B) winding up the slit tape with a rotating cylindrical heater and partially heating only the portion where the embossed portion of the tape is formed;
(C) winding a heated tape with a rotating cylindrical mold, and forming an embossed part by rotary vacuum forming ,
The styrene-based resin composition comprises 7-79.5% by mass of polystyrene resin (A), 0.5-3% by mass of high-impact polystyrene resin (B), and styrene-conjugated diene block copolymer (C). The manufacturing method of the embossed carrier tape containing 20-90 mass% . In steps (b) and (c)
A cylindrical heater in which a partial heating portion for heating a portion where the embossed portion of the tape is formed is arranged on the outer peripheral portion of the tape so that the embossed portion is formed in a partially heated portion of the tape; The embossing molding part for vacuum-sucking a tape in the direction of a molding die and forming an embossing part rotates synchronously with the cylindrical molding die arranged at the cylinder outer peripheral part. Manufacturing method of embossed carrier tape. The tape which consists of the said single layer sheet is heated by making it contact for 0.5 to 5.0 second with the cylindrical heater which has a heating part heated to 110-180 degreeC which has the shape corresponded to an embossing part. Item 3. A method for producing an embossed carrier tape according to Item 1 or 2. The method for producing an embossed carrier tape according to claim 2 or 3, wherein the area of the heating part pressed against the tape is 90 to 120% with respect to the area of the part where the embossed part is formed. The embossed carrier according to any one of claims 1 to 4, wherein the styrene-conjugated diene block copolymer (C) is a copolymer containing 70 to 90% by mass of styrene and 10 to 30% by mass of conjugated diene. Tape manufacturing method. A styrenic resin composition is biaxially stretched, the orientation relaxation stress value measured in accordance with ASTM D1504 is 0.2 to 0.8 MPa, and the thickness is 0.15 to 0.5 mm. A single layer sheet is slit into a tape shape, and the slit tape is wound up by a rotating cylindrical heater, and only the portion where the embossed portion of the tape is formed is partially heated, and then the cylindrical shape is rotated. An embossed carrier tape in which a tape heated by a mold is wound and an embossed part is formed by rotary vacuum forming ,
The styrene-based resin composition comprises 7-79.5% by mass of polystyrene resin (A), 0.5-3% by mass of high-impact polystyrene resin (B), and styrene-conjugated diene block copolymer (C). Embossed carrier tape containing 20 to 90% by mass . A cylindrical heater in which a partial heating portion for heating a portion where the embossed portion of the tape is formed is arranged on the outer peripheral portion of the tape so that the embossed portion is formed in a partially heated portion of the tape; , according to claim 6, a cylindrical forming die embossing unit for forming the embossed portion by vacuum sucking the tape in the direction of the molding die is disposed in the cylindrical outer peripheral portion rotates synchronously Embossed carrier tape. The tape which consists of the said single layer sheet is heated by making it contact for 0.5 to 5.0 second with the cylindrical heater which has a heating part heated to 110-180 degreeC which has the shape corresponded to an embossing part. Item 8. The embossed carrier tape according to Item 6 or 7 . The embossed carrier tape according to claim 7 or 8 , wherein the area of the heating part is 90 to 120% with respect to the area of the part where the embossed part is formed. The embossed carrier according to any one of claims 6 to 9, wherein the styrene-conjugated diene block copolymer (C) is a copolymer containing 70 to 90% by mass of styrene and 10 to 30% by mass of conjugated diene. tape.

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