JP5102538B2 - Water-dispersed acrylic adhesive tape or sheet for transporting electronic components - Google Patents

Description

  The present invention relates to an adhesive tape or sheet for transporting electronic components used for fixing radial / axial electronic components such as capacitors and resistors, and radial / axial electronic components such as capacitors and resistors. The present invention relates to an adhesive tape or sheet for transporting electronic components that contributes to transport.

  Where an axial or radical leaded electronic component such as a capacitor element, a capacitive element, a transistor element, or a resistor is manufactured, an adhesive tape or sheet for electronic component conveyance (electronic component process) is used to convey the electronic component intermediate product. Transport adhesive tape or sheet) (hereinafter, “tape or sheet” may be simply referred to as “tape” or “sheet”). In addition, the adhesive tape for transporting electronic components is used to transport electronic components to mounting plants that mount axial or radical-type electronic components with leads such as capacitor elements, capacitor elements, transistor elements, resistors, etc. Has been.

  Electronic parts and intermediate products are folded in a zigzag form after the lead wire is fixed on a mount (for example, kraft paper or resin liner) with an adhesive tape for transporting electronic parts. It is conveyed to the process. At this time, in order to maintain the alignment of the electronic component and the intermediate product in each environment, the lead part needs to be firmly fixed to the adhesive tape for transporting the electronic component in each environment. Moreover, when separating an electronic component and an intermediate product from the adhesive tape for conveying an electronic component, it is required that the lead wire does not shift to an adhesive.

  Conventionally, solvent-type pressure-sensitive adhesives (see Patent Document 1 and Patent Document 2) have been used for such applications, but these solvent-type pressure-sensitive adhesives are synthesized in an organic solvent. Volatilization is an environmental issue.

  In particular, in the case of a solvent-type acrylic pressure-sensitive adhesive, since the upper limit of the molecular weight is limited as a result of polymerization in an organic solvent, a sufficiently satisfactory pressure-sensitive adhesive tape for transporting electronic components could not be obtained. Therefore, conversion to a water-dispersed acrylic pressure-sensitive adhesive is expected. However, with an adhesive tape for transporting electronic parts using a water-dispersed acrylic pressure-sensitive adhesive, it is difficult to satisfy both the properties of the lead part (fixability) and the adhesive residue on the lead part.

  For these reasons, until now, no adhesive tape for transporting electronic components using an acrylic adhesive has existed in the world.

Japanese Patent Laid-Open No. 10-60394 Japanese Patent Laid-Open No. 11-349089

  Accordingly, the object of the present invention is to realize a water-dispersed pressure-sensitive adhesive that can be applied in an aqueous system, and particularly suitable for use as an electronic component process and a pressure-sensitive adhesive tape or sheet for transportation, An object of the present invention is to provide an acrylic pressure-sensitive adhesive tape or sheet excellent in both properties of adhesive residue on the lead part.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have selected both the components of the acrylic emulsion polymer and the physical property values, so that both the fixing property of the lead part and the adhesive residue on the lead part can be obtained. It has been found that an excellent water-dispersed acrylic pressure-sensitive adhesive tape or sheet can be obtained, and the present invention has been completed.

  That is, the present invention is an acrylic monomer containing (meth) acrylic acid ester as a main component and 0.3 to 4 parts by weight of a carboxyl group-containing monomer with respect to 100 parts by weight of all monomer components on at least one side of a substrate. A pressure-sensitive adhesive layer comprising an acrylic pressure-sensitive adhesive mainly comprising an acrylic emulsion-based polymer having a glass transition temperature of −30 to −15 ° C. obtained by emulsion polymerization of the mixture is provided. A water-dispersed acrylic pressure-sensitive adhesive tape or sheet for transporting electronic components is provided.

  The gel fraction of the acrylic emulsion polymer is preferably 50 to 70%, and the molecular weight of the sol content of the acrylic emulsion polymer is preferably 1,000,000 to 3,000,000.

  The acrylic pressure-sensitive adhesive preferably contains 1 to 50 parts by weight of a rosin-based or terpene-based tackifier having a softening point of 100 ° C. or higher with respect to 100 parts by weight of the acrylic emulsion-based polymer. The acrylic pressure-sensitive adhesive preferably contains 1 to 20 parts by weight of a tackifier having a softening point of 23 ° C. or less based on 100 parts by weight of the acrylic emulsion polymer.

Argument抜力is preferably 15 [N / 15mm] or more.

  According to the water-dispersed acrylic pressure-sensitive adhesive tape or sheet for transporting electronic components of the present invention, the water-dispersed pressure-sensitive adhesive that can be applied in water is realized, particularly for electronic component processes and transport, because it has the above-described configuration. It can be suitably used as a pressure-sensitive adhesive tape or sheet, and is excellent in both properties of the fixing property of the lead part and the adhesive residue on the lead part.

  The water-dispersed acrylic pressure-sensitive adhesive sheet for transporting electronic components according to the present invention comprises 0.3 to 4 parts by weight with respect to 100 parts by weight of (meth) acrylic acid ester as a main component and all monomer components on at least one side of the substrate. A pressure-sensitive adhesive comprising an acrylic pressure-sensitive adhesive mainly comprising an acrylic emulsion-based polymer obtained by emulsion polymerization of an acrylic monomer mixture containing a carboxyl group-containing monomer and having a glass transition temperature of −30 to −15 ° C. Layer (adhesive layer, pressure-sensitive adhesive layer, pressure-sensitive adhesive layer).

  In the water-dispersed acrylic pressure-sensitive adhesive sheet for transporting electronic components, the pressure-sensitive adhesive layer provided on one or both surfaces of the substrate is made of an acrylic pressure-sensitive adhesive mainly composed of an acrylic emulsion polymer. The acrylic emulsion polymer which is the main component of the acrylic pressure-sensitive adhesive has a glass transition temperature of -30 to -15 ° C (preferably -28 to -17 ° C, more preferably -25 to -15 ° C). When the glass transition temperature is lower than −30 ° C., there may be a problem that the adhesive remains on the lead part. On the other hand, when the glass transition temperature is higher than −15 ° C., the adhesiveness to the lead part is lowered, and electronic parts and intermediate products are produced. There may be a problem that cannot be held.

  Here, the glass transition temperature refers to a temperature at which the movement of the whole molecule becomes stronger than the interaction between the partial parts of the molecular structure and a large change in physical properties occurs. The glass transition temperature of the acrylic emulsion-based polymer was measured using a rheometric dynamic viscoelastic device (trade name “ARES”) with a sample thickness of about 1.5 mm and a φ7.9 mm parallel plate treatment. Using the tool, the temperature at the peak point of the obtained loss elastic modulus G ″ was measured at a frequency of 1 Hz and a heating rate of 5 ° C./min.

  The glass transition temperature of the acrylic emulsion polymer is an acrylic monomer mixture that forms an acrylic emulsion polymer by emulsion polymerization, and is at least (meth) acrylic acid ester as a main component and 100 parts by weight of all monomer components. On the other hand, it can be adjusted by selecting the composition of the acrylic monomer mixture containing 0.3 to 4 parts by weight of the carboxyl group-containing monomer. For example, select a combination of a (meth) acrylic acid ester and a carboxyl group-containing monomer, or select a combination of other monomers that can be copolymerized with the (meth) acrylic acid ester as the main monomer. It can be adjusted by.

  The acrylic monomer mixture is a mixture formed by emulsion polymerization of an acrylic emulsion polymer that is a main component of the acrylic pressure-sensitive adhesive used in the pressure-sensitive adhesive layer of the water-dispersed acrylic pressure-sensitive adhesive sheet for conveying electronic components, (Meth) acrylic acid ester as a component and a carboxyl group-containing monomer are contained.

As the (meth) acrylic acid ester, a (meth) acrylic acid alkyl ester can be suitably used. Examples of the (meth) acrylic acid alkyl ester include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, (meth) Isobutyl acrylate, s-butyl (meth) acrylate, t-butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, 2-Methylhexyl acrylate, isooctyl (meth) acrylate, nonyl (meth) acrylate, isononyl (meth) acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate, undecyl (meth) acrylate , Dodecyl (meth) acrylate, tridecyl (meth) acrylate, (me ) Tetradecyl acrylate, pentadecyl (meth) acrylate, hexadecyl (meth) acrylate, heptadecyl (meth) acrylate, octadecyl (meth) acrylate, nonadecyl (meth) acrylate, eicosyl (meth) acrylate (meta) ) Acrylic acid C _1-20 alkyl ester [preferably (meth) acrylic acid C _2-14 alkyl (linear or branched alkyl) ester].

  Moreover, as (meth) acrylic acid ester other than (meth) acrylic acid alkyl ester, for example, it has an alicyclic hydrocarbon group such as cyclopentyl (meth) acrylate, cyclohexyl (meth) acrylate, isobornyl (meth) acrylate ( And (meth) acrylic acid ester and (meth) acrylic acid ester having an aromatic hydrocarbon group such as phenyl (meth) acrylate.

  Such (meth) acrylic acid esters can be used alone or in combination of two or more. In addition, since the (meth) acrylic acid ester is used as a monomer main component of the acrylic monomer mixture, the ratio of the (meth) acrylic acid ester [particularly, the (meth) acrylic acid alkyl ester] is, for example, acrylic. It is important that the amount is 60% by weight or more (preferably 80% by weight or more) with respect to the total amount of monomer components in the monomer mixture.

  Examples of the carboxyl group-containing monomer include acrylic acid, methacrylic acid, maleic acid, crotonic acid, acrylic acid dimer, ω-carboxy-polycaprolactone monoacrylate, phthalic acid monohydroxyethyl acrylate, and the like. The carboxyl group-containing monomers can be used alone or in combination of two or more.

  In the acrylic monomer mixture, the carboxyl group-containing monomer is 0.3 to 4 parts by weight (preferably 0.5 to 2.5 parts by weight, more preferably 0 to 100 parts by weight of all monomer components of the acrylic monomer mixture. 0.5 to 2 parts by weight). When the amount of the carboxyl group-containing monomer is less than 0.3 parts by weight, the stability of the acrylic emulsion is lowered, and the acrylic emulsion-based polymer (acrylic emulsion-based polymer) is polymerized or acrylic containing the acrylic emulsion-based polymer as a main component. When applying the pressure sensitive adhesive, there may be a problem that aggregates are generated. If the amount is more than 4 parts by weight, the adhesion to the lead (lead part) will increase, making it difficult to separate from the water-dispersed acrylic pressure-sensitive adhesive sheet for transporting electronic components, and glue remaining on the lead (lead part). (Glue residue) may occur.

  In addition to the above monomer components, the acrylic monomer mixture can stabilize emulsion particles, improve the adhesion of the pressure-sensitive adhesive layer to the substrate, and improve the initial adhesion to the adherend. For the purpose, a copolymerizable monomer may be contained. The amount of the copolymerizable monomer used is 60% by weight or less (for example, 0.1 to 60% by weight), preferably 25% by weight or less (for example, 0.5 to 25% by weight) based on the total amount of monomer components in the acrylic monomer mixture. %) Can be appropriately selected according to the type of each monomer. In addition, a copolymerizable monomer can be used individually or in combination of 2 or more types.

  Examples of copolymerizable monomers include vinyl ester monomers such as vinyl acetate, styrene monomers such as styrene, epoxy group-containing monomers such as glycidyl acrylate and glycidyl methacrylate, 2-hydroxyethyl acrylate, and 2-hydroxypropyl acrylate. Hydroxyl group-containing monomers such as N, N-diethylacrylamide, amide group-containing monomers such as N-isopropylacrylamide, and amino group-containing monomers such as acryloylmorpholine.

  Moreover, in the acrylic monomer mixture, a polyfunctional monomer may be contained in order to adjust the gel fraction of the acrylic emulsion polymer described later. That is, a polyfunctional monomer may be copolymerized when an acrylic emulsion polymer is polymerized using an acrylic monomer mixture. Examples of such polyfunctional monomers include diethylene glycol diacrylate, diethylene glycol dimethacrylate, ethylene glycol diacrylate, ethylene glycol dimethacrylate, tetraethylene glycol diacrylate, tetraethylene glycol dimethacrylate, neopentyl glycol diacrylate, neopentyl glycol dimethacrylate. , 1,6-hexanediol diacrylate, 1,6-hexanediol dimethacrylate, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, pentaerythritol triacrylate, pentaerythritol trimethacrylate, dipentaerythritol hexamethacrylate, etc. (Meth) acrylates, divinyl base Polyfunctional aromatic vinyl compounds such as Zen, and the like. In addition, a polyfunctional monomer can be used individually or in combination of 2 or more types.

  The acrylic emulsion polymer is a polymer formed by emulsion polymerization of the acrylic monomer mixture, and has a glass transition temperature of −30 to −15 ° C. (preferably −28 to −17 ° C., more The polymer is preferably −25 to −15 ° C., and in the water-dispersed acrylic pressure-sensitive adhesive sheet for transporting electronic components, it is excellent in both the property of fixing the lead part and the adhesive residue on the lead part. It is the main component of the acrylic pressure-sensitive adhesive forming the pressure-sensitive adhesive layer that provides the pressure-sensitive adhesive surface.

  The acrylic emulsion polymer can be synthesized by an ordinary emulsion polymerization method by adding a polymerization initiator and an emulsifier to the acrylic monomer mixture. For emulsion polymerization, any method such as general batch polymerization, continuous dropping polymerization, and divided dropping polymerization can be used, and the method is not particularly limited. The polymerization can be performed at a temperature in the range of about 5 to 100 ° C., for example, depending on the type of initiator used.

  The emulsifier is not particularly limited as long as it is usually used in emulsion polymerization. For example, sodium lauryl sulfate, ammonium lauryl sulfate, sodium dodecylbenzenesulfonate, sodium polyoxyethylene lauryl sulfate, sodium polyoxyethylene alkyl ether sulfate, poly Anionic emulsifiers such as ammonium oxyethylene alkyl phenyl ether sulfate, sodium polyoxyethylene alkyl phenyl ether sulfate, sodium polyoxyethylene alkyl sulfosuccinate, polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene fatty acid ester, polyoxy Nonionic emulsifiers such as ethylene polyoxypropylene block polymer can be used. Further, as the emulsifier, various reactive emulsifiers having a radical polymerizable functional group such as vinyl group, propenyl group, isopropenyl group, vinyl ether group (vinyloxy group), allyl ether group (allyloxy group) may be used.

  The compounding quantity of an emulsifier is 1-10 weight part with respect to 100 weight part of acrylic monomer mixtures, Preferably it is about 0.5-5 weight part. If the blending amount of the emulsifier is less than 0.1 parts by weight, stable emulsification may not be maintained. On the other hand, if the blending amount of the emulsifier exceeds 5 parts by weight, the emulsifier may contaminate the adherend, It may become impossible to hold parts and intermediate products. In addition, an emulsifier can be used individually or in combination of 2 or more types.

  The polymerization initiator is not particularly limited as long as it is usually used for emulsion polymerization. For example, 2,2′-azobisisobutyronitrile, 2,2′-azobis (2-amidinopropane) dihydrochloride, Azos such as 2,2'-azobis (N, N'-dimethyleneisobutylamidine), persulphates such as potassium persulfate and ammonium persulfate, peroxides such as benzoyl peroxide and t-butyl hydroperoxide And redox polymerization initiators such as hydrogen peroxide solution and ascorbic acid, hydrogen peroxide solution and iron (II) salt, persulfate and sodium hydrogen sulfite.

  The amount of the polymerization initiator used is appropriately selected according to the type and type of acrylic monomer (for example, the (meth) acrylic acid alkyl ester). For example, for 100 parts by weight of the acrylic monomer mixture. About 0.001 to 0.1 parts by weight. In addition, a polymerization initiator can be used individually or in combination of 2 or more types.

  A chain transfer agent may be used to adjust the molecular weight of the acrylic emulsion polymer. Such a chain transfer agent is not particularly limited, and examples thereof include lauryl mercaptan, mercaptoacetic acid, 2-mercaptoethanol, 2-ethylhexyl thioglycolate, and 2,3-dimethylcapto-1-propanol. It is done. In addition, a chain transfer agent can be used individually or in combination of 2 or more types.

  Furthermore, in order to adjust the gel fraction of the acrylic emulsion polymer, a crosslinking agent may be added in addition to copolymerizing the polyfunctional monomer component when the acrylic emulsion polymer is polymerized. .

  Examples of the crosslinking agent include polyfunctional epoxy crosslinking agents, isocyanate crosslinking agents, aziridine crosslinking agents, melamine resin crosslinking agents, carbodiimide crosslinking agents, and the like. In addition, polyfunctional means a thing more than bifunctional.

  Specific examples of such a crosslinking agent include, for example, N, N, N ′, N′-tetraglycidyl-m-xylenediamine, 1,3-bis (N, N-glycidylaminomethyl) cyclohexane (commercial product). Name “Tetrad C” manufactured by Mitsubishi Gas Chemical Co., Ltd.), 1,6-hexanediol glycidyl ether, polyethylene glycol diglycidyl ether, polyglycerol polyglycidyl ether, and other epoxy-based crosslinking agents, trade name “Epocross WS-500” (Nippon Shokubai) Oxazoline-based crosslinking agents such as trade name “Chemite PZ-33” (manufactured by Nippon Shokubai Co., Ltd.), block isocyanate-based crosslinking agents such as tolylene diisocyanate (block), and trade name “Elastolon BN” -69 "(Daiichi Kogyo Seiyaku Co., Ltd.) , Trade name "Carbodilite V-02" (Nisshinbo Co., Ltd.), trade name "Carbodilite V-02-L02" (Nisshinbo Co., Ltd.), trade name "Carbodilite V-04" (Nisshinbo Co., Ltd.), trade name Examples thereof include carbodiimide crosslinking agents such as “Carbodilite E-01” (manufactured by Nisshinbo Industries, Inc.) and trade name “Carbodilite E-02” (manufactured by Nisshinbo Industries Inc.).

  Further, when the acrylic emulsion polymer is polymerized, a monomer having a carbonyl group (for example, diacetone acrylamide) may be copolymerized and further used in combination with a hydrazine crosslinking agent that reacts with the carbonyl group. Examples of such hydrazine-based cross-linking agents include hydrazine-based cross-linking agents such as adipic acid dihydrazide, trade names “Amicure VDH” and “Amicure UDH” (manufactured by Ajinomoto Fine Techno Co., Ltd.).

  These crosslinking agents are added in such an amount that the gel fraction of the acrylic emulsion polymer falls within a desired range depending on the composition and molecular weight of the acrylic emulsion polymer. For example, when adding a hydrazine type crosslinking agent as a crosslinking agent, it is about 0.1-3 weight part (preferably 0.3-1 weight part) with respect to 100 weight part of acrylic emulsion type polymers. Moreover, you may use a crosslinking agent individually or in combination of 2 or more types. In addition, in order to adjust the gel fraction, a crosslinking agent other than the above (for example, a hydrogen peroxide crosslinking agent) may be added to the acrylic monomer mixture forming the acrylic emulsion polymer.

  The gel fraction of the acrylic emulsion polymer is adjusted to 50 to 70%, preferably 55 to 68%, more preferably 60 to 65%. If the gel fraction is less than 50%, there may be a problem that the adhesive remains on the lead part (residue remaining on the lead part). If it becomes higher than 70%, the adhesion to the lead portion is lowered, and there may be a problem that electronic components and intermediate products cannot be held.

In the water-dispersed acrylic pressure-sensitive adhesive sheet for transporting electronic components of the present invention, in order to adjust the gel fraction of the acrylic emulsion polymer that is the main component of the acrylic pressure-sensitive adhesive, after providing the pressure-sensitive adhesive layer on the support, The gel fraction of the acrylic emulsion polymer can be increased by irradiating the adhesive layer with an active energy ray and performing a curing treatment. As active energy rays, ionizing radiation such as α rays, β rays, γ rays, neutron rays, electron rays, ultraviolet rays, and the like are used. The irradiation dose of active energy rays may be adjusted so that the gel fraction has a desired value, but ionizing radiation is usually 20 Mrad or less, preferably 10 Mrad or less, and ultraviolet rays are usually 3000 mJ / cm ² or less. . When there is too much irradiation amount, there exists a concern about deterioration of a base material.

  In addition, when irradiating an ultraviolet-ray, the ultraviolet-ray to be used has a preferable wavelength range of 180-460 nm, and it is preferable to use a mercury lamp and a metahalide lamp as the generation source. In addition, when the curing treatment is performed by irradiating with ultraviolet rays, it is preferable that a photoreaction initiator (photosensitizer) is included in the acrylic monomer mixture in advance. Examples of the photoreaction initiator include benzoin, benzoin methyl ether, benzoin ethyl ether, dibenzyl, and benzyldimethyl ketal.

The gel fraction of the acrylic emulsion polymer was determined by sampling about 0.1 g of a sample and precisely weighing it, and immersing it in about 50 ml of ethyl acetate at room temperature for 1 week. Is dried for about 1 hour and weighed, and calculated using the following formula.
Gel fraction of acrylic emulsion polymer (% by weight) = [(weight after immersion / drying) / weight of sample] × 100

  The sol molecular weight (weight average molecular weight of the sol) of the acrylic emulsion polymer is adjusted to 1 million to 2 million, preferably 1.2 million to 1.9 million, and more preferably 1.5 million to 1.8 million. If the molecular weight of the sol is less than 1 million, there may be a problem that the adhesive remains on the lead part. If the molecular weight exceeds 2 million, a problem such as a decrease in pulling force or a decrease in retention occurs. There is a case.

  The molecular weight of the acryl emulsion polymer sol can be adjusted, for example, depending on the polymer polymerization conditions such as the type and addition amount of the polymerization initiator and the polymerization temperature.

The molecular weight of the sol content of the acrylic emulsion polymer (weight average molecular weight of the sol) was obtained by sampling about 0.1 g of a sample and precisely weighing it, and immersing it in about 50 ml of ethyl acetate at room temperature for 1 week. Then, the ethyl acetate solution in which the insoluble component and the sol component are dissolved is separated. Ethyl acetate can be dried under reduced pressure at 30 ° C. from an ethyl acetate solution in which the sol is dissolved, and can be determined by GPC (gel permeation chromatography).
Apparatus: (Product name) HLC-8120GPC [manufactured by Tosoh Corporation]
Column: (column product number) TSKgel GMH _HR- H (S) [manufactured by Tosoh Corporation] × 2 (2-column connection)
Flow rate: 0.5ml / min
Injection volume: 100 μl
Column temperature: 40 ° C
Eluent: THF (tetrahydrofuran)
Injection sample concentration: 0.1% by weight
Detector: differential refractometer The weight average molecular weight is calculated in terms of polystyrene.

  The acrylic pressure-sensitive adhesive is a pressure-sensitive adhesive mainly composed of the acrylic emulsion polymer. In the water-dispersed acrylic pressure-sensitive adhesive sheet for transporting electronic components, both the fixability of the lead part and the adhesive residue on the lead part An adhesive layer that provides an adhesive surface with excellent properties is formed.

  The content of the acrylic emulsion polymer in the acrylic pressure-sensitive adhesive is not particularly limited as long as it exhibits both the property of fixing the lead part and the adhesive residue on the lead part on the pressure-sensitive adhesive surface, but at least 50% by weight (for example, 50 to 100% by weight), preferably 70% by weight or more (for example, 70 to 100% by weight). The acrylic pressure-sensitive adhesive may be composed only of an acrylic emulsion polymer, or may be composed of an acrylic emulsion polymer as a main component and other components.

  As other components contained in the acrylic pressure-sensitive adhesive, various known and commonly used additives are used as long as they exhibit both the property of fixing the lead part and the adhesive residue on the lead part on the adhesive surface. Examples thereof include tackifiers (tackifier resins), anti-aging agents, fillers, and colorants. In addition, these additives can be used individually or in combination of 2 or more types.

  In particular, the acrylic pressure-sensitive adhesive preferably contains a tackifier (tackifier resin) from the viewpoint of improving the adhesive residue on the lead part and improving the adhesion to the lead part during low temperature application.

  Examples of such tackifier resins include rosin tackifier resins, terpene tackifier resins, phenol tackifier resins, hydrocarbon tackifier resins, ketone tackifier resins, polyamide tackifier resins, and epoxy tackifiers. Examples include tackifying resins and elastomeric tackifying resins. Moreover, tackifying resin can be used individually or in combination of 2 or more types.

  As the softening point of the tackifying resin, for example, a value measured according to JIS K 2531 (ring and ball method) can be adopted.

  Examples of rosin-based tackifying resins include unmodified rosins such as gum rosin, wood rosin and tall oil rosin (raw rosin), and modified rosins modified by hydrogenation, disproportionation, polymerization, etc. of these unmodified rosins ( In addition to hydrogenated rosin, disproportionated rosin, polymerized rosin, and other chemically modified rosins), various rosin derivatives and the like are included. Examples of the rosin derivative include rosin ester compounds obtained by esterifying unmodified rosin with alcohols, and modified rosin esters obtained by esterifying modified rosins such as hydrogenated rosin, disproportionated rosin and polymerized rosin with alcohols. Rosin esters such as compounds; Unmodified rosin and modified rosin (hydrogenated rosin, disproportionated rosin, polymerized rosin, etc.) modified with unsaturated fatty acids; Unsaturated fatty acid modified rosins; Rosin esters modified with unsaturated fatty acids Unsaturated rosin, modified rosin (hydrogenated rosin, disproportionated rosin, polymerized rosin, etc.), unsaturated fatty acid modified rosins and unsaturated fatty acid modified rosin esters Rosin alcohols such as unmodified rosin, modified rosin and various rosin derivatives Oxazines (especially, rosin esters) and the like metal salts of.

  Examples of terpene-based tackifier resins include terpene resins such as α-pinene polymers, β-pinene polymers, dipentene polymers, and modified terpene resins (phenol-modified, aromatic-modified, hydrogenated-modified). And modified terpene resins such as terpene-phenol resins, styrene modified terpene resins, aromatic modified terpene resins, hydrogenated terpene resins, and the like.

  Examples of phenolic tackifier resins include condensates of various phenols with formaldehyde. Examples of the phenols include phenol, m-cresol, 3,5-xylenol, p-alkylphenol, resorcin and the like. Specifically, the phenolic tackifier resin includes, for example, an alkylphenolic resin, a xylene-formaldehyde resin, and the like. In addition, the phenolic tackifier resin includes resole obtained by addition reaction of the above phenols and formaldehyde with an alkali catalyst, novolak obtained by condensation reaction of the above phenols and formaldehyde with an acid catalyst, and rosin. A rosin phenol resin obtained by adding phenol to an acid (non-modified rosin, modified rosin, various rosin derivatives, etc.) with an acid catalyst and thermal polymerization can also be used.

  Examples of hydrocarbon-based tackifying resins include aliphatic hydrocarbon resins [olefins having 4 to 5 carbon atoms and dienes (olefins such as butene-1, isobutylene, pentene-1; butadiene, 1,3-pentadiene, isoprene). Aliphatic hydrocarbon polymers such as dienes, etc.], aliphatic cyclic hydrocarbon resins [so-called “C4 petroleum fraction” and “C5 petroleum fraction” after cyclization and dimerization and polymerization. Alicyclic hydrocarbon resins, polymers of cyclic diene compounds (cyclopentadiene, dicyclopentadiene, ethylidene norbornene, dipentene, etc.) or hydrogenated products thereof, the following aromatic hydrocarbon resins and aliphatic / aromatic systems Alicyclic hydrocarbon resins obtained by hydrogenating aromatic rings of petroleum resins, etc.], aromatic hydrocarbon resins [vinyl group-containing aromatic hydrocarbons having 8 to 10 carbon atoms] (Polymers of styrene, vinyltoluene, α-methylstyrene, indene, methylindene, etc.)], aliphatic / aromatic petroleum resins (such as styrene-olefin copolymers), aliphatic / alicyclic petroleum Various hydrocarbon resins such as resins, hydrogenated hydrocarbon resins, coumarone resins and coumarone indene resins can be used.

  Examples of the ketone tackifying resin include condensates of ketones such as methyl ethyl ketone, methyl isobutyl ketone, acetophenone, cyclohexanone and methylcyclohexanone with formaldehyde.

  Among these, from the viewpoint of improving the adhesive residue of the acrylic pressure-sensitive adhesive, a tackifying resin having a softening point of 100 ° C. or higher (eg 100 to 200 ° C.) [preferably 110 ° C. or higher (eg 110 to 170 ° C.)] is preferable. In particular, among tackifying resins having a softening point of 100 ° C. or higher, rosin-based tackifying resins and terpene-based tackifying resins having a softening point of 100 ° C. or higher are preferable.

  Examples of commercially available rosin tackifier resins and terpene tackifier resins having a softening point of 100 ° C. or higher include “Superester E720” (softening point: 100 ° C.), “Superester” manufactured by Arakawa Chemical Industries, Ltd. "E730-55" (softening point: 125 ° C), "Superester E865" (softening point: 160 ° C), "Superester NS120B" (softening point: 120 ° C), "Tamanol E-100" (softening point: 125 ° C) ); “Hariesta SK370N” (softening point: 100 ° C.), “Hariesta SK816E” (softening point: 145 ° C.), “Hariesta SK822E” (softening point: 170 ° C.) and the like manufactured by Harima Chemicals.

  In the acrylic pressure-sensitive adhesive, the addition amount of the tackifying resin having a softening point of 100 ° C. or higher is, for example, about 1 to 50 parts by weight (preferably 5 to 30 parts by weight) with respect to 100 parts by weight of the acrylic emulsion polymer. It is. In addition, when adding more than 50 weight part, the problem that the fixability of the lead part at the time of low temperature sticking falls may generate | occur | produce.

  Further, from the viewpoint of improving the adhesion to the lead part at the time of low-temperature application, a tackifying resin having a softening point of 23 ° C. or lower [a liquid tackifying resin at room temperature (23 ° C.)] is preferable, particularly the 23 ° C. or lower. Among the tackifying resins having the above softening point, rosin-based tackifying resins and terpene-based tackifying resins having a softening point of 23 ° C. or lower are preferable.

  Examples of commercially available tackifying resins having a softening point of 23 ° C. or lower include “Harriesta SK501NS” manufactured by Harima Chemical Co., Ltd .; “YS Polystar T” manufactured by Yashara Chemical Co., Ltd .; “Hercolin D” manufactured by Hercules Co .; Examples thereof include “Super Ester A18” manufactured by Chemical Industries.

  In the acrylic pressure-sensitive adhesive, the addition amount of the tackifying resin having a softening point of 23 ° C. or less is, for example, about 1 to 20 parts by weight (preferably 2 to 10 parts by weight) with respect to 100 parts by weight of the acrylic emulsion polymer. is there. In addition, when adding more than 20 weight part, the problem that the adhesiveness to a lead part etc. falls may generate | occur | produce.

  The tackifying resin is added as an optional component, and the acrylic pressure-sensitive adhesive may not contain the tackifying resin. The kind of tackifying resin to be added and the amount of addition are not particularly limited as long as both properties of the fixing property of the lead part and the adhesive residue on the lead part can be exhibited on the adhesive surface of the acrylic pressure-sensitive adhesive layer. Are appropriately selected. As the tackifier resin, a tackifier resin having a softening point of 100 ° C. or higher, or a tackifier resin having a softening point of 23 ° C. or lower may be used alone or in combination. Moreover, you may use together with tackifying resin whose softening point exceeds 23 degreeC and is less than 100 degreeC. Further, only a tackifying resin having a softening point of more than 23 ° C. and less than 100 ° C. may be used without using a tackifying resin having a softening point of 100 ° C. or higher and a tackifying resin having a softening point of 23 ° C. or lower. .

  The water-dispersed acrylic pressure-sensitive adhesive sheet for transporting electronic components is an acrylic monomer mixture containing (meth) acrylic acid ester as a main component and 0.3 to 4 parts by weight of a carboxyl group-containing monomer with respect to 100 parts by weight of all monomer components. And a pressure-sensitive adhesive layer made of an acrylic pressure-sensitive adhesive mainly composed of an acrylic emulsion-based polymer having a glass transition temperature of −30 to −15 ° C. is provided on at least one surface of the substrate. It has an adhesive layer made of an acrylic adhesive. For this reason, the water-dispersed acrylic pressure-sensitive adhesive sheet for transporting electronic components can exhibit both the fixing property of the lead portion and the adhesive residue on the lead portion on the pressure-sensitive adhesive surface of the pressure-sensitive adhesive layer made of the acrylic pressure-sensitive adhesive. It can be used for electronic component transport applications and electronic component process applications (for example, fixing of electronic components, processing of electronic components, etc.).

  The water-dispersed acrylic pressure-sensitive adhesive sheet for transporting electronic components may be in the form of a double-sided pressure-sensitive adhesive sheet whose both surfaces are pressure-sensitive adhesive surfaces, or may be in the form of a single-sided pressure-sensitive adhesive sheet in which only one surface is a pressure-sensitive adhesive surface. Good. When the water-dispersed acrylic pressure-sensitive adhesive sheet for transporting electronic components is in the form of a double-sided pressure-sensitive adhesive sheet, both pressure-sensitive adhesive surfaces may be pressure-sensitive adhesive surfaces of the pressure-sensitive adhesive layer made of the acrylic pressure-sensitive adhesive, or one of them. The pressure-sensitive adhesive surface may be a pressure-sensitive adhesive surface of a pressure-sensitive adhesive layer made of the acrylic pressure-sensitive adhesive, and the other pressure-sensitive adhesive surface may be a pressure-sensitive adhesive surface of a pressure-sensitive adhesive layer made of another pressure-sensitive adhesive.

  The water-dispersed acrylic pressure-sensitive adhesive sheet for transporting electronic components may be formed in a form wound in a roll shape, or may be formed in a form in which sheets are laminated. That is, the water-dispersed acrylic pressure-sensitive adhesive sheet for transporting electronic components can have a form such as a sheet form or a tape form. In addition, as a water-dispersed acrylic pressure-sensitive adhesive sheet for transporting electronic components in a state or form wound in a roll shape, a state or form wound in a roll shape with the adhesive surface protected by a release film (separator) It may have and has the state or form wound in the shape of a roll in the state protected by the exfoliation processing layer (back processing layer) formed in the other side of a substrate (support). It may be. In addition, as a release treatment agent (release agent) used when forming a release treatment layer (back treatment layer) on the surface of the substrate (support), for example, a silicone release agent, a long-chain alkyl release agent, or the like Is mentioned.

  The water-dispersed acrylic pressure-sensitive adhesive sheet for transporting electronic components is a single separator type having a configuration in which the pressure-sensitive adhesive surface is protected only by a single release film (release liner) that has been subjected to release treatment on both sides of the substrate. Alternatively, a double separator type having a configuration in which the adhesive surface is protected by two release films that have been subjected to a release treatment on at least one surface of the substrate may be used.

  The water-dispersed acrylic pressure-sensitive adhesive sheet for transporting electronic components may have a pressure-sensitive adhesive layer made of other pressure-sensitive adhesives in addition to the pressure-sensitive adhesive layer made of the acrylic pressure-sensitive adhesive. Furthermore, the water-dispersed acrylic pressure-sensitive adhesive sheet for transporting electronic components preferably has a release film (separator) on the pressure-sensitive adhesive layer for the purpose of protecting the pressure-sensitive adhesive surface. Furthermore, the water-dispersed acrylic pressure-sensitive adhesive sheet for transporting electronic components may have other layers (for example, an intermediate layer, an undercoat layer, etc.).

  The pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer by other pressure-sensitive adhesive is not particularly limited, and is a known pressure-sensitive adhesive (pressure-sensitive adhesive) (for example, acrylic pressure-sensitive adhesive, rubber pressure-sensitive adhesive, vinyl alkyl ether pressure-sensitive adhesive). Silicone adhesive, polyester adhesive, polyamide adhesive, urethane adhesive, fluorine adhesive, epoxy adhesive, etc.). The pressure-sensitive adhesive may be used alone or in combination of two or more.

  Examples of the intermediate layer include one or more intermediate layers provided between the base material and the pressure-sensitive adhesive layer. As such an intermediate layer, for example, a coating layer of a release agent for the purpose of imparting peelability, a coating layer of a primer for the purpose of improving adhesion, a layer for the purpose of imparting good deformability, Layer for the purpose of increasing the adhesion area to the adherend, layer for the purpose of improving the adhesion to the adherend, layer for the purpose of following the surface shape of the adherend well, heating Examples include a layer for the purpose of improving the processability for reducing the adhesive force due to the layer, and a layer for the purpose of improving the peelability after heating.

  Although it does not restrict | limit especially as a peeling film, For example, a conventional release paper etc. can be used. Specifically, as the release film, for example, in addition to a substrate having a release treatment layer (release treatment layer) with a release treatment agent (release treatment agent) on at least one surface, a fluorine-based polymer (for example, polytetra Low adhesive substrates made of fluoroethylene, polychlorotrifluoroethylene, polyvinyl fluoride, polyvinylidene fluoride, tetrafluoroethylene / hexafluoropropylene copolymer, chlorofluoroethylene / vinylidene fluoride copolymer, etc. A low-adhesive substrate made of an adhesive polymer (for example, an olefin resin such as polyethylene or polypropylene) can be used. In the case of a low-adhesive substrate, both surfaces can be used as a release surface, while in a substrate having a release treatment layer, the release treatment layer surface is used as a release surface (release treatment surface). can do.

  As the release film, for example, a release film (base material having a release treatment layer) in which a release treatment layer is formed on at least one surface of the release film substrate can be suitably used. Such release film substrates include polyester films (polyethylene terephthalate film, etc.), olefin resin films (polyethylene film, polypropylene film, etc.), polyvinyl chloride films, polyimide films, polyamide films (nylon films), rayon films. In addition to plastic base film (synthetic resin film) such as paper, paper (quality paper, Japanese paper, kraft paper, glassine paper, synthetic paper, top coat paper, etc.), these can also be laminated and co-extruded. Examples include layered materials (2 to 3 layer composites).

  The release treatment agent is not particularly limited, and for example, a silicone release treatment agent, a fluorine release treatment agent, a long-chain alkyl release treatment agent, or the like can be used. You may use a mold release processing agent individually or in combination of 2 or more types. The release film that has been subjected to the release treatment with the release treatment agent is formed by, for example, a known forming method.

  The thickness of the release film is not particularly limited, but can be selected from the range of, for example, 12 to 250 μm (preferably 20 to 200 μm) from the viewpoint of ease of handling and economy. The release film may have either a single layer or a laminated form.

  As a base material, it can select from a well-known base material suitably as a base material for adhesive tapes or a sheet | seat, and can use it. Specifically, the base material is not particularly limited. For example, a plastic base material (for example, a plastic base material such as a plastic film or a sheet), a metal base material (for example, a metal foil such as an aluminum foil or a nickel foil). And thin plates such as a paper base material, a fiber base material (for example, a base material made of cloth, non-woven fabric, net, aramid fiber, etc.).

  Among these, from the viewpoint of workability, a plastic base material and a paper base material are preferable, and a paper base material (paper base material) is particularly preferable.

  Examples of the plastic base material include olefins containing α-olefin as a monomer component such as polyethylene (PE), polypropylene (PP), ethylene-propylene copolymer, and ethylene-vinyl acetate copolymer (EVA). Resin; Polyester resin such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT); polyvinyl chloride (PVC); vinyl acetate resin; polyphenylene sulfide (PPS); polyamide (nylon), Amide resins such as wholly aromatic polyamide (aramid); polyimide resins; polyetheretherketone (PEEK) and the like. These materials can be used alone or in combination of two or more.

  The plastic base material may control deformability such as elongation by stretching treatment or the like.

  Moreover, as a paper-type base material (paper base material), it can select and use suitably from various paper-type base materials, for example, Japanese paper, a thin paper, a western paper, a fine paper, a glassine paper, a kraft paper, a Kurpack paper, Examples include crepe paper, clay coat paper, top coat paper, synthetic paper, mixed paper, and composite paper. The paper base material can be selected in a wide range according to the application within a range where the mechanical strength, handling property and the like are not impaired. Generally, a crepe paper having a thickness of about 0.05 to 0.2 mm is used.

  The surface of the substrate is chemically or chemically treated by conventional surface treatments such as corona treatment, chromic acid treatment, ozone exposure, flame exposure, high piezoelectric impact exposure, ionizing radiation treatment, etc. An oxidation treatment or the like by a physical method may be performed. Further, a coating treatment with an undercoat agent or a release agent may be applied.

  For example, on the surface of a paper-based substrate, known and commonly used surface treatments such as easy-to-slip treatment and antistatic treatment, primer coating to firmly bond the paper-based substrate and the adhesive layer, and an adhesive layer Ozone treatment, corona treatment, etc. may be applied to improve the anchoring performance (anchor effect).

  The primer is not particularly limited as long as it has affinity for both the paper-based substrate and the pressure-sensitive adhesive layer. For example, a known or commonly used adhesive can be used. Specifically, the primer is compatible with paper-based substrates such as SBR (styrene-butadiene rubber), MBR [MMA (methyl methacrylate) and BR (butadiene rubber) copolymer], acrylic polymers, and the like. A compound obtained by graft polymerization of a compatible compound and a compound having an affinity for the pressure-sensitive adhesive layer is preferably used.

  The primer can be applied onto a paper-based substrate by an impregnation treatment or a conventional coating method. In addition, when a paper-type base material and an adhesive layer can be laminated | stacked with high adhesive strength etc., it is not necessarily required to perform primer coating.

  The thickness of the substrate can be appropriately selected according to strength, flexibility, purpose of use, and the like, and is, for example, 1000 μm or less (for example, 1 to 1000 μm), preferably 1 to 500 μm, and more preferably about 3 to 300 μm. However, it is not limited to these. In addition, the base material may have any form of a single layer or a lamination.

  The water-dispersed acrylic pressure-sensitive adhesive sheet for transporting electronic components of the present invention has a base material and a pressure-sensitive adhesive layer formed of the acrylic pressure-sensitive adhesive, and a known or conventional method for forming a pressure-sensitive adhesive layer (for example, a coating method). , A transfer method, etc.) to form the pressure-sensitive adhesive layer on one side or both sides of the substrate.

  For example, when the water-dispersed acrylic pressure-sensitive adhesive sheet for transporting electronic parts of the present invention is a single-sided pressure-sensitive adhesive sheet with a base material provided with a pressure-sensitive adhesive layer made of the acrylic pressure-sensitive adhesive on one side of the base material, A method of applying a pressure-sensitive adhesive on one side (coating method) or a pressure-sensitive adhesive layer on a release film such as a release liner to form a pressure-sensitive adhesive layer. It can produce by the method (transfer method) which transcribe | transfers on a material and forms an adhesive layer on the single side | surface of a base material.

  The thickness of the pressure-sensitive adhesive layer made of the acrylic pressure-sensitive adhesive is not particularly limited, and can be selected, for example, from a range of about 10 to 400 μm, and preferably about 20 to 300 μm.

  The water-dispersed acrylic pressure-sensitive adhesive sheet for transporting electronic components is 15 [N / 15 mm] or more (for example, 15 to 30 [N / 15 mm]), preferably 18 [N / 15 mm] or more (for example, 18 to 30 [N / 15 mm]). If the pulling force is less than 15 [N / 15 mm], the fixation to the lead portion cannot be exhibited, and it may be difficult to transport the electronic component using the water-dispersed acrylic pressure-sensitive adhesive sheet for transporting the electronic component, If the pulling force exceeds 30 [N / 15 mm], it may be difficult to pull out the electronic component after transporting the electronic component.

  The pulling force is fixed by sandwiching both wire parts of the U-shaped tin-plated lead wire between the mount and the adhesive surface of the adhesive layer made of acrylic adhesive of the water-dispersed acrylic adhesive sheet for transporting electronic components. From the above, it is defined by the stress when the U-shaped tin-plated lead wire is pulled out in the direction of the U-shaped semicircle.

  As shown in FIG. 1, the pulling force is obtained by preparing a pulling force measurement sheet using a water-dispersed acrylic pressure-sensitive adhesive sheet for transporting electronic components to obtain the pulling force, and at a pulling speed of 300 mm / min in an atmosphere of 23 ° C. The lead wire is pulled out in the direction of the drawing direction a, the stress at the time of drawing is measured, the maximum value of stress (the maximum value excluding the peak top in the initial measurement) is read, and the maximum value of the stress is drawn It can be determined by setting the force (N / 15 mm).

  In FIG. 1, 1a shows the configuration of the drawing force measurement sheet, and 1b shows a cross section of the drawing force measurement sheet. Further, 11 is a lead wire, 12 is a water-dispersed acrylic pressure-sensitive adhesive sheet for transporting electronic components for which a pulling force is required, 13 is a mount, and a is the pulling direction. In FIG. 1, the water-dispersed acrylic pressure-sensitive adhesive sheet 12 for transporting electronic components has the form of a single-sided pressure-sensitive adhesive sheet with a base material composed of an acrylic pressure-sensitive adhesive layer 12 a and a base material 12 b. This is only one of the forms that the water-dispersed acrylic pressure-sensitive adhesive sheet for transporting electronic components can take.

  In the drawing force measurement sheet of FIG. 1, a U-shaped tin-plated lead wire [cross-sectional shape: circular shape with a diameter of 0.6 mm, full length: 100 mm, U-shaped width (interval): 5 mm] is used as the lead wire 11. As the mount 13, a mount made of kraft paper [for example, thick kraft paper (trade name “K liner” manufactured by Oji Paper Co., Ltd.)] is used.

  As shown in FIG. 1, the pull-out force measurement sheet is a water-dispersed acrylic adhesive for transporting electronic components under the conditions of 23 ° C., 0.5 MPa, 1 sec. It is produced by taping with a sheet (width 15 mm) (by pinching and fixing).

  The water-dispersed acrylic pressure-sensitive adhesive sheet for transporting electronic components according to the present invention is a water-dispersed acrylic pressure-sensitive adhesive sheet using a water-based coating-type pressure-sensitive adhesive that can be applied in water. It exhibits both properties of adhesive residue. And using such a characteristic, it is used for the conveyance use of an electronic component, the processing use of an electronic component, the fixation use of an electronic component, etc.

  Electronic components that can use water-dispersed acrylic pressure-sensitive adhesive sheets for transporting electronic components include, for example, lead wires; resistor elements; capacitor elements; circuit boards; capacitor elements, capacitor elements, transistor elements, resistors and other axial types or radical types Examples include leaded electronic components and intermediate components.

  In the electronic component, the material (for example, the material of the lead portion) to be fixed to the water-dispersed acrylic pressure-sensitive adhesive sheet for transporting the electronic component is not particularly limited, and various plastic materials (for example, olefin resin, polyester resin) In addition, various engineering plastics), metal materials, paper, glass fiber-containing composite materials, and the like. Moreover, the shape of the site | part fixed is not restrict | limited in particular, You may have various surface shapes, such as a plane, a rough surface, and a curved surface.

  Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples.

Example 1
Water: 180 parts by weight, n-butyl acrylate: 50 parts by weight, n-butyl methacrylate: 49 parts by weight, acrylic acid: 1 part by weight in a reaction vessel equipped with a cooling tube, a nitrogen introduction tube, a thermometer, and a stirring device Parts, and nonionic anionic surfactant (trade name “Hytenol LA16”, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.): 2 parts by weight of an emulsion solution obtained by emulsifying with an emulsifier was charged, and the atmosphere was purged with nitrogen for 1 hour with stirring. . Thereafter, the inner bath temperature during the polymerization was controlled at 55 ° C. A polymerization initiator aqueous solution composed of a polymerization initiator (trade name “V-50” manufactured by Wako Pure Chemical Industries, Ltd.): 0.05 part by weight and water: 2 parts by weight was added thereto to initiate polymerization. The reaction was completed 5 hours after the start of polymerization. Thereafter, the mixture was neutralized with 10% by weight of aqueous ammonia to prepare an acrylic emulsion polymer (sometimes referred to as “acrylic emulsion polymer (A)”).
Acrylic emulsion polymer (A): 0.1 parts by weight of 100 parts by weight of a crosslinking agent [1,3-bis (N, N-glycidylaminomethyl) cyclohexane; trade name “Tetrad C” manufactured by Mitsubishi Gas Chemical Co., Ltd.] Part (100 parts by weight solid content of the adhesive) was added to prepare an acrylic adhesive.
The prepared acrylic pressure-sensitive adhesive is placed on a crepe paper (trade name “C-30M” manufactured by Miki Paper Industries Co., Ltd., thickness: 0.125 mm) as a paper base so that the thickness after drying is 40 μm. It apply | coated and dried and the acrylic adhesive sheet was produced.

(Example 2)
The monomer component contained in the emulsion solution was formulated in the same manner as in Example 1 except that 2-ethylhexyl acrylate: 50 parts by weight, n-butyl methacrylate: 49 parts by weight, and acrylic acid: 1 part by weight. An acrylic emulsion polymer (sometimes referred to as “acrylic emulsion polymer (B)”) was prepared.
Subsequently, an acrylic pressure-sensitive adhesive was prepared using the acrylic emulsion polymer (B) with the same formulation as in Example 1, and then the same formulation as in Example 1 using the prepared acrylic pressure-sensitive adhesive. An acrylic pressure-sensitive adhesive sheet was prepared.

(Example 3)
The monomer component contained in the emulsion solution was prepared in the same manner as in Example 1, except that n-butyl acrylate: 60 parts by weight, n-butyl methacrylate: 39 parts by weight, and acrylic acid: 1 part by weight. An acrylic emulsion polymer (sometimes referred to as “acrylic emulsion polymer (C)”) was prepared.
Subsequently, after preparing an acrylic pressure-sensitive adhesive using the acrylic emulsion polymer (C) in the same formulation as in Example 1, the same formulation as in Example 1 using the prepared acrylic pressure-sensitive adhesive. An acrylic pressure-sensitive adhesive sheet was prepared.

Example 4
Acrylic emulsion polymer (A): 0.1 parts by weight of 100 parts by weight of a crosslinking agent [1,3-bis (N, N-glycidylaminomethyl) cyclohexane; trade name “Tetrad C” manufactured by Mitsubishi Gas Chemical Co., Ltd.] Part (100 parts by weight solid content of the adhesive), 10 parts by weight of rosin tackifier (trade name “Superester E730-55” manufactured by Arakawa Chemical Industries, softening point: 125 ° C.) Was made.
Subsequently, an acrylic pressure-sensitive adhesive sheet was prepared using the prepared acrylic pressure-sensitive adhesive in the same manner as in Example 1.

(Example 5)
Acrylic emulsion polymer (C): 0.1 parts by weight of 100 parts by weight of a crosslinking agent [1,3-bis (N, N-glycidylaminomethyl) cyclohexane; trade name “Tetrad C” manufactured by Mitsubishi Gas Chemical Co., Ltd.] An acrylic pressure-sensitive adhesive was prepared by adding 5 parts by weight (100 parts by weight of solid content with respect to the pressure-sensitive adhesive) and a tackifier (trade name “Haristar SK501NS” manufactured by Harima Chemicals, Inc .; liquid at 23 ° C.).
Subsequently, an acrylic pressure-sensitive adhesive sheet was prepared using the prepared acrylic pressure-sensitive adhesive in the same manner as in Example 1.

(Comparative Example 1)
The monomer component contained in the emulsion solution was prepared in the same manner as in Example 1 except that 2-ethylhexyl acrylate: 49 parts by weight, n-butyl acrylate: 49 parts by weight, and acrylic acid: 2 parts by weight. An acrylic emulsion polymer (sometimes referred to as “acrylic emulsion polymer (D)”) was prepared.
Subsequently, after preparing an acrylic pressure-sensitive adhesive using the acrylic emulsion polymer (D) in the same formulation as in Example 1, the same formulation as in Example 1 using the prepared acrylic pressure-sensitive adhesive. An acrylic pressure-sensitive adhesive sheet was prepared.

(Comparative Example 2)
The monomer components contained in the emulsion solution were the same as in Example 1 except that n-butyl acrylate: 27 parts by weight, n-butyl methacrylate: 72 parts by weight, and acrylic acid: 1 part by weight An acrylic emulsion polymer (sometimes referred to as “acrylic emulsion polymer (E)”) was prepared.
Subsequently, after preparing an acrylic pressure-sensitive adhesive using the acrylic emulsion polymer (E) in the same formulation as in Example 1, the same formulation as in Example 1 using the prepared acrylic pressure-sensitive adhesive. An acrylic pressure-sensitive adhesive sheet was prepared.

(Comparative Example 3)
The acrylic emulsion polymer (““ N-butyl acrylate: 50 parts by weight, n-butyl methacrylate: 50 parts by weight) was used in the same formulation as in Example 1 except that the monomer component contained in the emulsion solution was 50 parts by weight. Acrylic emulsion polymer (F) ”may be prepared).
Subsequently, after preparing an acrylic pressure-sensitive adhesive using the acrylic emulsion polymer (F) in the same formulation as in Example 1, the same formulation as in Example 1 using the prepared acrylic pressure-sensitive adhesive. An acrylic pressure-sensitive adhesive sheet was prepared.
However, Comparative Example 3 could not be used as a pressure-sensitive adhesive sheet due to aggregates produced in large quantities during the production of the polymer (F).

(Comparative Example 4)
The monomer component contained in the emulsion solution was prepared in the same manner as in Example 1 except that n-butyl acrylate: 50 parts by weight, n-butyl methacrylate: 45 parts by weight, and acrylic acid: 5 parts by weight. An acrylic emulsion polymer (sometimes referred to as “acrylic emulsion polymer (G)”) was prepared.
Subsequently, an acrylic adhesive was prepared using the acrylic emulsion polymer (G) in the same formulation as in Example 1, and then the same formulation as in Example 1 using the prepared acrylic adhesive. An acrylic pressure-sensitive adhesive sheet was prepared.

(Comparative Example 5)
Acrylic emulsion polymer (A): 1 part by weight of 100 parts by weight of a crosslinking agent [1,3-bis (N, N-glycidylaminomethyl) cyclohexane; trade name “Tetrad C” manufactured by Mitsubishi Gas Chemical Co., Ltd.] Acrylic pressure-sensitive adhesive was prepared by adding 100 parts by weight of the solid content to the pressure-sensitive adhesive.
Subsequently, an acrylic pressure-sensitive adhesive sheet was prepared in the same manner as in Example 1 using the prepared acrylic pressure-sensitive adhesive.

(Evaluation)
For the acrylic pressure-sensitive adhesive sheets of Examples and Comparative Examples, glass transition temperature, gel fraction, molecular weight of sol, fixability of lead part (pulling force), adhesive residue on the lead part by the following measuring method or evaluation method And low temperature characteristics were measured or evaluated. The measurement results and evaluation results are shown in Table 1.

(Glass-transition temperature)
In the acrylic pressure-sensitive adhesive sheets of Examples and Comparative Examples, the glass transition temperature of the acrylic emulsion-based polymer, which is the main component of the acrylic pressure-sensitive adhesive, is measured using a dynamic viscoelastic device (trade name “ARES”) manufactured by Rheometric. Using a jig with a φ7.9 mm parallel plate with a sample thickness of about 1.5 mm, the temperature at the peak point of the obtained loss elastic modulus was measured at a frequency of 1 Hz and a heating rate of 5 ° C./min. The temperature was taken as the glass transition temperature of the acrylic emulsion polymer.

(Gel fraction)
In the acrylic pressure-sensitive adhesive sheets of Examples and Comparative Examples, the gel fraction of the acrylic emulsion-based polymer, which is the main component of the acrylic pressure-sensitive adhesive, was sampled and weighed approximately 0.1 g, and this was approximately 50 ml. After soaking in ethyl acetate at room temperature for 1 week, the solvent-insoluble matter was taken out, dried at 130 ° C. for about 1 hour, weighed, and calculated using the following formula.
Gel fraction of acrylic emulsion polymer (% by weight) = [(weight after immersion / drying) / weight of sample] × 100
In the measurement of the gel fraction of the acrylic emulsion polymer, a solid content obtained by evaporating and drying the emulsion was used as a sample.

(Molecular weight of sol)
In the acrylic pressure-sensitive adhesive sheets of Examples and Comparative Examples, the weight average molecular weight (molecular weight of the sol) of the acrylic emulsion polymer that is the main component of the acrylic pressure-sensitive adhesive was obtained by sampling about 0.1 g of a sample. This is precisely weighed and immersed in about 50 ml of ethyl acetate at room temperature for 1 week, and then the ethyl acetate solution in which the insoluble component and the sol component are dissolved is separated. Ethyl acetate was dried under reduced pressure at 30 ° C. from an ethyl acetate solution in which the sol was dissolved, and measured by GPC (gel permeation chromatography).
Apparatus: (Product name) HLC-8120GPC [manufactured by Tosoh Corporation]
Column: (column product number) TSKgel GMH _HR- H (S) [manufactured by Tosoh Corporation] × 2 (2-column connection)
Flow rate: 0.5ml / min
Injection volume: 100 μl
Column temperature: 40 ° C
Eluent: THF (tetrahydrofuran)
Injection sample concentration: 0.1% by weight
Detector: differential refractometer The weight average molecular weight was calculated in terms of polystyrene. Moreover, in the measurement of the molecular weight of the sol content of the acrylic emulsion polymer, a solid content obtained by evaporating and drying the emulsion was used as a sample.

(Lead fixability)
U-shaped lead wire with a spacing of 5 mm on a mount (thick kraft paper, trade name “K liner” manufactured by Oji Paper Co., Ltd.) [cross-sectional shape: circular shape with a diameter of 0.6 mm, total length: 100 mm, U-shape Was pulled with an acrylic pressure-sensitive adhesive sheet (width: 15 mm) under the conditions of 23 ° C., 0.5 MPa, and 1 sec to produce a drawing force measurement sheet (see FIG. 1).
This pulling force measurement sheet was stored in a 120 ° C. atmosphere for 1 hour, and then stored in a 23 ° C. atmosphere for 1 hour. After storage, using a tensile tester in an atmosphere of 23 ° C., the lead wire was drawn in the drawing direction (U-shaped semicircle portion direction, corresponding to the drawing direction a in FIG. 1) at a drawing speed of 300 mm / min. The maximum value was taken as the pulling force.

(Adhesive residue on the lead)
Adhesion of the adhesive was observed on the lead wire separated from the pulling force measurement sheet after evaluating the above (fixability of the lead part). The case where no adhesive residue was observed was evaluated as “◯”, the case where adhesive residue was partially observed was “Δ”, and the case where adhesive residue was observed on the entire lead wire was evaluated as “X”.

(Low temperature characteristics)
In an atmosphere of 0 ° C., an acrylic adhesive sheet having a width of 15 mm was placed with the adhesive layer face up, and a U-shaped lead wire on the adhesive layer (glue layer) [cross-sectional shape: diameter 0 .6 mm circle, total length: 100 mm, U-shaped width (interval): 5 mm] [n = 5 (number of lead wires = 5)]. A pressure of 500 g was applied to these lead wires for 1 second. Then, the adhesive tape was pinched and the adhesive layer surface (glue surface) was turned upside down. When turned over, the adhesion between the adhesive layer and the lead wire is maintained without falling from the adhesive layer, and the number of lead wires (n) remaining on the adhesive layer is 4 or more (n Of 4 or more) was evaluated as good (◯), and 3 or less (n was 3 or less).

  In Table 1, “-” means that the evaluation was not achieved.

From Table 1, it can be confirmed that the acrylic pressure-sensitive adhesive sheets of the examples have a pulling force of 15 (N / 15 mm) or more, good low-temperature characteristics, and excellent lead part fixability. It was confirmed that the adhesive residue on the part was also good.
On the other hand, in the acrylic pressure-sensitive adhesive sheet of Comparative Example 1, since the glass transition temperature of the acrylic emulsion polymer, which is the main component of the acrylic pressure-sensitive adhesive, is low, adhesive residue was partially observed on the lead wires. In the acrylic pressure-sensitive adhesive sheet of Comparative Example 2, since the glass transition temperature of the acrylic emulsion polymer that is the main component of the acrylic pressure-sensitive adhesive is high, the low-temperature characteristics are poor and the fixability of the lead wire at low temperatures is poor. It was. Since the acrylic pressure-sensitive adhesive sheet of Comparative Example 3 did not contain a carboxyl group-containing monomer, the stability of the pressure-sensitive adhesive was poor and the evaluation was not achieved. In the acrylic pressure-sensitive adhesive sheet of Comparative Example 4, since the amount of the carboxyl group-containing monomer was large, an adhesive residue was observed on the entire surface of the lead wire, and the adhesive residue on the lead portion was poor. The acrylic pressure-sensitive adhesive sheet of Comparative Example 5 has a high gel fraction of the acrylic emulsion polymer that is the main component of the acrylic pressure-sensitive adhesive, and the sol content of the acrylic emulsion polymer that is the main component of the acrylic pressure-sensitive adhesive. Because of the low weight average molecular weight, the pulling force was low, the low-temperature characteristics were poor, and the lead wire was poor in fixability.

It is the schematic of a drawing force measuring sheet.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1a Structure of drawing force measurement sheet 1b Cross section of drawing force measurement sheet 11 Lead wire 12 Water-dispersed acrylic pressure-sensitive adhesive tape or sheet for conveying electronic parts 12a Acrylic pressure-sensitive adhesive layer 12b Base material 13 Mount a Mount direction

Claims (6)

Emulsion polymerization of an acrylic monomer mixture containing (meth) acrylic acid ester as a main component and 0.3 to 4 parts by weight of a carboxyl group-containing monomer with respect to 100 parts by weight of all monomer components on at least one side of a paper-based substrate Water for transporting electronic components, characterized in that an adhesive layer made of an acrylic adhesive mainly composed of an acrylic emulsion polymer having a glass transition temperature of -30 to -15 ° C is provided. Dispersed acrylic adhesive tape or sheet.   The water-dispersed acrylic pressure-sensitive adhesive tape or sheet for transporting electronic components according to claim 1, wherein the gel fraction of the acrylic emulsion-based polymer is 50 to 70%.   The water-dispersed acrylic pressure-sensitive adhesive tape or sheet for transporting electronic components according to claim 1 or 2, wherein the molecular weight of the sol of the acrylic emulsion polymer is 1 million to 3 million. Acrylic adhesive, rosin above 100 ° C. softening point or terpene tackifiers, claims 1 to 3 any one containing 1 to 50 parts by weight of the acrylic emulsion polymer 100 parts by weight A water-dispersed acrylic pressure-sensitive adhesive tape or sheet for transporting electronic components as described in 1. Acrylic adhesive, a softening point of 23 ° C. or less of a tackifier, electronic component conveying according to claim 1 any one containing 1 to 20 parts by weight of the acrylic emulsion polymer 100 parts by weight Water-dispersed acrylic pressure-sensitive adhesive tape or sheet. 6. The water-dispersed acrylic pressure-sensitive adhesive tape or sheet for transporting electronic components according to any one of claims 1 to 5, wherein a pulling force is 15 [N / 15 mm] or more.

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