JP5565173B2 - Heat-resistant temporary adhesive tape - Google Patents

Description

  The present invention relates to a heat-resistant temporary wearing adhesive tape used for temporarily fixing or protecting a component having a polyimide resin surface in an electronic component manufacturing process.

  Generally, adhesive tapes such as dicing tapes and back grind tapes are used in the manufacturing process of electronic components. Since these adhesive tapes are used for fixing and protecting parts, they have strong adhesive strength that can withstand environmental conditions in each manufacturing process, eliminating the need for fixing and protection. It is desirable that can be easily peeled off.

  As an adhesive tape having such properties, Patent Document 1 discloses one in which a radiation curable adhesive layer and an adhesive layer having a storage elastic modulus in a specific range are provided on one surface of a base film. ing. Patent Document 2 discloses a re-peelable pressure-sensitive adhesive composition comprising a water-affinity acrylic pressure-sensitive adhesive, an active energy ray-curable compound, a photopolymerization initiator, and a crosslinking agent. These show strong adhesive strength before irradiating with energy rays, etc., and fix and protect the adherend appropriately, but when irradiated with energy rays etc., the adhesive strength decreases significantly and can be easily peeled off from the adherend. It becomes that.

JP 2002-53819 A JP 2000-345131 A

  By the way, in recent years, in the manufacturing process of an electronic component, the component with the adhesive tape attached is often exposed to a high temperature. For this reason, the pressure-sensitive adhesive tape used in the manufacturing process of electronic components is also required to have heat resistance that can withstand high temperature conditions. However, the pressure-sensitive adhesive tape used to temporarily fix or protect the components has a low adhesive strength when exposed to high temperatures, and peels off during the process, or adheres firmly to the adherend after the process, There was a problem that adhesive residue was generated.

  The present invention has been made in view of the above problems, and is an adhesive tape used for temporarily fixing or protecting an electronic component, particularly a component having a polyimide resin surface, and is an initial stage for the polyimide resin surface. Adhesive strength is high, and even when exposed to high temperatures, the adhesive strength is difficult to decrease, and it has the adhesive strength necessary for fixation and protection. An object is to provide a heat-resistant temporary adhesive tape that can be peeled off.

  As a material for forming the pressure-sensitive adhesive layer constituting the pressure-sensitive adhesive tape, the present inventor has conducted intensive research to solve the above-mentioned problems. As a material for forming the pressure-sensitive adhesive layer, an acrylic polymer, an energy beam polymerizable oligomer, By selecting a polymerization initiator and a crosslinking agent, and further adjusting the mass ratio of the hydroxyl group-containing monomer and the carboxyl group-containing monomer constituting the acrylic polymer, the polymer was exposed to a high temperature while being stuck to the polyimide resin surface. Even in such a case, it was found that the adhesive strength is difficult to decrease, and an adhesive tape that does not cause adhesive residue upon peeling and removal is obtained, and the present invention has been completed.

  Specifically, the present invention provides the following.

  (1) A heat-resistant temporary adhesive tape used for temporarily fixing or protecting a component having a polyimide resin surface in a manufacturing process of an electronic component, the acrylic polymer on the heat-resistant substrate, An adhesive layer made of an adhesive layer forming material containing an energy ray polymerizable oligomer, a polymerization initiator, and a crosslinking agent is formed, and the acrylic polymer is mainly composed of an acrylate ester, Copolymerized with acrylic acid ester and copolymerizable hydroxyl group-containing monomer, or copolymerized with acrylic acid ester and copolymerizable hydroxyl group and carboxyl group-containing monomer based on acrylic ester The mass ratio of the hydroxyl group-containing monomer to the carboxyl group-containing monomer is 51:49 to 100: 0, The initiator is characterized by having a weight reduction rate of 50% or less by thermogravimetry when the temperature is increased from 30 ° C. to 190 ° C. at a temperature increase rate of 10 ° C./min and maintained at 190 ° C. for 30 minutes. Heat-resistant temporary wearing adhesive tape.

(2) 180 ° peeling adhesive strength of the pressure-sensitive adhesive layer on the polyimide resin surface having a surface free energy of 30 to 50 mJ / m ² and an arithmetic average roughness Ra of 0.4 to 0.6 μm (JIS Z0237) is 0.8 to 15 N / 25 mm after 20 minutes have passed from the polyimide resin surface, and 0.8 to 20 N / 25 mm after heating at 150 ° C. for 90 minutes, And after hardening by the energy ray irradiation after the said heating, the heat-resistant temporary attachment adhesive tape as described in (1) which is 0.4 N / 25mm or less.

  (3) The heat shrinkage ratio (based on JIS C2151) of the heat-resistant substrate is 1.0% or less in the MD direction and 1.0% or less in the TD direction, as described in (1) or (2) Heat-resistant temporary wearing adhesive tape.

  (4) A temporary adherend to which the heat-resistant temporary wearing adhesive tape according to any one of (1) to (3) is attached.

  According to the heat-resistant temporary wearing pressure-sensitive adhesive tape of the present invention, the initial adhesive strength to the polyimide resin surface is high, and even when exposed to high temperatures, the adhesive strength is unlikely to decrease, and the adhesive strength necessary for fixing and protection is obtained. It can be easily peeled off without leaving glue when it is removed and removed.

It is sectional drawing which showed typically the adhesive tape which concerns on one Embodiment of this invention.

  Hereinafter, specific embodiments of the present invention will be described in detail. However, the present invention is not limited to the following embodiments, and may be implemented with appropriate modifications within the scope of the object of the present invention. be able to.

  The heat-resistant temporary wearing pressure-sensitive adhesive tape of the present invention (hereinafter referred to as pressure-sensitive adhesive tape) is a heat-resistant temporary wearing pressure-sensitive adhesive tape used for temporarily fixing or protecting a component having a polyimide resin surface in the manufacturing process of electronic components. In addition, an adhesive layer made of an adhesive layer forming material containing an acrylic polymer, an energy ray polymerizable oligomer, a polymerization initiator, and a crosslinking agent is formed on the heat-resistant substrate, The acrylic polymer has an acrylic ester as a main component, and is obtained by copolymerization of the acrylic ester with a copolymerizable hydroxyl group-containing monomer, or has an acrylic ester as a main component, and the acrylic ester. Obtained by copolymerization with a copolymerizable hydroxyl group and carboxyl group-containing monomer. The mass ratio of the polymer is 51:49 to 100: 0, and the polymerization initiator was heated from 30 ° C. to 190 ° C. at a temperature rising rate of 10 ° C./min and maintained at 190 ° C. for 30 minutes. The weight reduction rate by thermogravimetry is 50% or less. In the manufacturing process of electronic components, conventional adhesive tapes used to temporarily fix or protect the components have a reduced adhesive strength when exposed to high temperatures and peel off during the process, or after the process is completed, The adhesive adheres firmly to the kimono, and adhesive residue is generated. In view of such problems, the present invention provides an acrylic polymer, an energy ray polymerizable oligomer, a polymerization initiator stable under high temperature conditions, a crosslinking agent as a material for forming an adhesive layer constituting an adhesive tape. And further adjusting the mass ratio of the hydroxyl group-containing monomer and the carboxyl group-containing monomer constituting the acrylic polymer, thereby enabling the pressure-sensitive adhesive tape suitable for fixing and protecting components having a polyimide resin surface, that is, polyimide resin The initial adhesive strength to the surface is high, and even when exposed to high temperatures, the adhesive strength is difficult to decrease, and has adhesive strength necessary for fixation and protection. It has been found for the first time that an easily peelable pressure-sensitive adhesive tape can be obtained.

  First, the structure of the adhesive tape of this invention is demonstrated using drawing. FIG. 1 is a cross-sectional view schematically showing an adhesive tape 10 according to an embodiment of the present invention. In FIG. 1, the pressure-sensitive adhesive tape 10 has a pressure-sensitive adhesive layer 2 and a release layer 3 sequentially formed on a substrate 1, but is not limited thereto. Hereinafter, the substrate 1, the pressure-sensitive adhesive layer 2, the release layer 3, and the pressure-sensitive adhesive tape 10 will be described in this order.

[Base material]
In the pressure-sensitive adhesive tape of the present invention, a base material having heat resistance is used. In the present invention, a heat-resistant substrate refers to a substrate having a melting point higher than 120 ° C. that can withstand use at an assumed heating temperature (120 ° C.) in the manufacturing process of electronic components. A base material having a melting point higher than 180 ° C. is preferable. In the pressure-sensitive adhesive tape of the present invention, the base material preferably has a heat shrinkage ratio (conforming to JIS C2151, 150 ° C. × 30 min) of 1.0% or less for both MD and TD, and 0.5% or less. Is more preferable. Furthermore, the base material is preferably a base material that does not hinder the transmission of energy rays and has the necessary strength and flexibility. For example, a polyester resin, a polypropylene resin, a polyvinyl chloride resin, a fluorine resin, a polystyrene resin Resins, poly (meth) acrylic resins, cellulose resins, polycarbonate resins, polyamide resins, polyolefin resins, polyester resins, polyvinyl alcohol resins, polyimide resins, phenol resins, polyurethane resins, etc. A synthetic resin film made of resin is used. These can be used alone or in combination of two or more. Moreover, a single layer may be sufficient and the laminated body of two or more layers may be sufficient. From the viewpoint of mechanical strength, a uniaxially stretched or biaxially stretched film is preferred. Since the adhesive tape of the present invention is used to temporarily fix and / or protect an electronic component in the manufacturing process of the electronic component, the heat resistance, dimensional stability, energy ray permeability, flexibility, In addition to strength and the like, it is preferable to use a polyester-based resin that is excellent in rigidity, extensibility, suitability for lamination, and chemical resistance.

  Examples of the polyester resin include polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, polybutylene naphthalate, polyarylate, polytetramethylene terephthalate, etc. Among these, the viewpoint that it is easy to handle and is inexpensive. Therefore, polyethylene terephthalate is particularly preferable.

  Although the thickness of a base material is not specifically limited, It is preferable that it is 30-300 micrometers, and it is more preferable that it is 50-100 micrometers. If it is the said range, since the form of an adhesive tape can be maintained, workability | operativity, such as sticking and peeling of an adhesive tape, will become favorable. In addition, since warp, slack, breakage and the like hardly occur and sufficient mechanical strength is exhibited, it is also possible to supply and process in a continuous belt shape. Furthermore, in the manufacturing process of the electronic component, the surface of the electronic component that is the adherend can be well protected. If the thickness exceeds the above-mentioned thickness, excessive performance may increase the cost.

  In addition, when an energy ray is a light ray, it is preferable that the light transmittance of 400 nm or less of a base material is 80% or more. The light transmittance can be measured using a commercially available spectrophotometer, for example, MPC2200 manufactured by Shimadzu Corporation.

  The formation method of a base material is not specifically limited, For example, conventionally well-known film forming methods, such as a solution casting method, a melt-extrusion method, and a calendar method, can be used. Moreover, you may use the commercially available base material previously formed into a film form by the said method.

  In order to improve the wettability with the pressure-sensitive adhesive, the substrate has a known ease such as corona treatment, plasma treatment, ozone treatment, flame treatment, primer treatment, vapor deposition treatment, alkali treatment, etc. on one side or both sides. An adhesion treatment may be performed.

[Adhesive layer]
In the pressure-sensitive adhesive tape of the present invention, the pressure-sensitive adhesive layer is formed on the heat-resistant substrate. The pressure-sensitive adhesive layer is made of a material for forming a pressure-sensitive adhesive layer containing an acrylic polymer, an energy beam polymerizable oligomer, a polymerization initiator, and a crosslinking agent. The acrylic polymer mainly contains an acrylate ester. As a component, obtained by copolymerization of the above-mentioned acrylic acid ester and a copolymerizable hydroxyl group-containing monomer, or the main component of the acrylic acid ester and a copolymerizable hydroxyl group and carboxyl group-containing monomer. The mass ratio of the hydroxyl group-containing monomer to the carboxyl group-containing monomer is 51:49 to 100: 0, and the polymerization initiator is from 30 ° C. at a temperature rising rate of 10 ° C./min. The weight reduction rate by thermogravimetry when the temperature is raised to 190 ° C. and maintained at 190 ° C. for 30 minutes is 50% or less.

(Acrylic polymer)
In the pressure-sensitive adhesive tape of the present invention, the pressure-sensitive adhesive layer is made of a material for forming a pressure-sensitive adhesive layer containing an acrylic polymer as a main ingredient which is excellent in transparency, heat resistance, heat and humidity resistance, durability, coating suitability, and the like. Become. The acrylic polymer is not particularly limited, and examples thereof include an acrylic ester copolymer obtained by copolymerizing an acrylic ester and another monomer. Examples of the acrylate ester include ethyl acrylate, n-butyl acrylate, 2-ethylhexyl acrylate, isooctyl acrylate, isononyl acrylate, hydroxylethyl acrylate, propylene glycol acrylate, acrylamide, and glycidyl acrylate. It is done. These can be used alone or in combination of two or more. In the present invention, among the above acrylate esters, in particular, n-butyl acrylate and 2-ethylhexyl acrylate are excellent in transparency, heat resistance, moist heat resistance, durability, suitability for coating, etc. This is preferable in terms of cost.

  Other monomers include, for example, methyl acrylate, methyl methacrylate, styrene, acrylonitrile, vinyl acetate, acrylic acid, methacrylic acid, itaconic acid, hydroxylethyl acrylate, hydroxylethyl methacrylate, propylene glycol acrylate, acrylamide Methacrylamide, glycidyl acrylate, glycidyl methacrylate, dimethylaminoethyl methacrylate, tert-butylaminoethyl methacrylate, and n-ethylhexyl methacrylate. These can be used alone or in combination of two or more. In the present invention, methacrylic acid-n-ethylhexyl is preferable among the other monomers.

  In the pressure-sensitive adhesive tape of the present invention, the acrylic polymer has an acrylic ester as a main component and is obtained by copolymerization of the acrylic ester with a copolymerizable hydroxyl group-containing monomer, or an acrylic ester as a main component. And obtained by copolymerization of the acrylic acid ester with a copolymerizable hydroxyl group- and carboxyl group-containing monomer, and the mass ratio of the hydroxyl group-containing monomer to the carboxyl group-containing monomer is 51:49 to 100: 0. It is preferable that it is 75: 25-100: 0. If it is in the said range, generation | occurrence | production of adhesive residue can be prevented and the fall of the effective adhesive force by energy ray irradiation can be anticipated. In the present invention, the main component means that the copolymerization ratio is 51% by mass or more, and preferably 65% by mass or more.

  The copolymerizable hydroxyl group-containing monomer is not particularly limited as long as it has a copolymerizable polymerizable group and a hydroxyl group in its structure. For example, 2-hydroxyethyl acrylate, 2-hydroxyacrylate Examples thereof include hydroxypropyl, 2-hydroxybutyl acrylate, 3-chloro-2-hydroxypropyl acrylate, polyethylene glycol acrylate, and the like.

  The copolymerizable carboxyl group-containing monomer is not particularly limited as long as it has a copolymerizable polymerizable group and a carboxyl group in its structure. For example, acrylic acid, methacrylic acid, carboxyethyl ( Examples include meth) acrylate, carboxypentyl (meth) acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid.

  In the pressure-sensitive adhesive tape of the present invention, the mass average molecular weight (Mw) of the acrylic polymer is preferably in the range of 100,000 to 1,100,000, and more preferably in the range of 200,000 to 900,000. If it is the said range, it has sufficient initial stage adhesive force and sufficient intensity | strength with respect to a polyimide resin surface. The mass average molecular weight is a value in terms of polystyrene when measured by gel permeation chromatography (GPC).

(Energy beam polymerizable oligomer)
The pressure-sensitive adhesive tape of the present invention contains an energy ray polymerizable oligomer as the pressure-sensitive adhesive layer forming material. The energy ray-polymerizable oligomer is not particularly limited as long as it can be polymerized by irradiation with energy rays, and examples thereof include oligomers such as photoradical polymerizability, photocationic polymerizability, and photoanion polymerizability. . Among these, a photo-radically polymerizable oligomer is preferable. This is because the curing speed is high, and a wide variety of compounds can be selected. Furthermore, physical properties such as adhesiveness before curing and peelability after curing can be easily controlled to desired ones. . Examples of the radical photopolymerizable oligomer include urethane (meth) acrylate, polyester (meth) acrylate, epoxy (meth) acrylate, polyol (meth) acrylate, polyether (meth) acrylate, melamine (meth) acrylate, and silicone-based. (Meth) acrylate etc. are mentioned, and these may be used alone or in combination of two or more.

  The mass average molecular weight (Mw) of the energy beam polymerizable oligomer is not particularly limited, but is preferably 250 to 5000, and more preferably 250 to 1500. If it is in the said range, a desired adhesive force will be shown before energy beam irradiation, and it can peel easily, without adhesive residue remaining after energy beam irradiation. The mass average molecular weight is a value in terms of polystyrene when measured by gel permeation chromatography (GPC).

  The content of the energy ray polymerizable oligomer in the pressure-sensitive adhesive layer forming material is preferably 10 to 60 parts by mass, and more preferably 20 to 50 parts by mass with respect to 100 parts by mass of the acrylic polymer. By adjusting the amount of the energy beam polymerizable oligomer, it is possible to control the adhesive strength after irradiation with the energy beam. If it exists in the said range, since the crosslinking density after energy beam irradiation will become sufficient, appropriate peelability can be implement | achieved. In addition, it is difficult for adhesive residue to adhere to the adherend due to a decrease in cohesion.

  The pressure-sensitive adhesive layer forming material may contain an energy ray polymerizable monomer that can be polymerized by irradiation with energy rays, in addition to the energy ray polymerizable oligomer. As the radical photopolymerizable monomer, a polyfunctional acrylate or a polyfunctional methacrylate is preferable. For example, trimethylol methane tri (meth) acrylate or trimethylol ethane tri having three or more (meth) acryloyl groups in one molecule. (Meth) acrylate, trimethylolpropane tri (meth) acrylate, tetramethylolmethanetetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, dipentaerythritol penta (meth) acrylate, pentaerythritol tri (meth) acrylate Of these, an ethylene oxide or a propylene oxide adduct is preferred. When these are irradiated with energy rays, the pressure-sensitive adhesive layer-forming material is cured by three-dimensional crosslinking to reduce the pressure-sensitive adhesive force, and the pressure-sensitive adhesive cohesive force is increased so as not to transfer to the adherend surface. It is because it has a function.

  When the energy ray polymerizable oligomer and the energy ray polymerizable monomer are contained in the pressure-sensitive adhesive layer forming material, the total content is 10 to 60 masses per 100 mass parts of the acrylic polymer. Parts, preferably 20 to 50 parts by mass. By adjusting these total contents, it becomes possible to control the adhesive strength after irradiation with energy rays. If it exists in the said range, since the crosslinking density after energy beam irradiation will become sufficient, appropriate peelability can be implement | achieved. In addition, it is difficult for adhesive residue to adhere to the adherend due to a decrease in cohesion.

  Examples of energy rays include rays such as far ultraviolet rays, ultraviolet rays, near ultraviolet rays, and infrared rays, electromagnetic waves such as X-rays and γ rays, electron beams, proton rays, and neutron rays. In view of the curing speed, the availability of the irradiation device, the price, etc., curing by ultraviolet irradiation is preferable.

(Polymerization initiator)
The pressure-sensitive adhesive tape of the present invention contains a polymerization initiator as the pressure-sensitive adhesive layer forming material. According to the polymerization initiator, the sensitivity of the energy beam polymerizable oligomer is enhanced, so that it is possible to reduce the polymerization curing time by the energy beam and the energy beam irradiation amount. In the pressure-sensitive adhesive tape of the present invention, the polymerization initiator has a weight reduction rate by thermogravimetry when the temperature is increased from 30 ° C. to 190 ° C. at a temperature increase rate of 10 ° C./min and maintained at 190 ° C. for 30 minutes. It is characterized by being 50% or less, and preferably the weight reduction rate is 20% or less. According to the pressure-sensitive adhesive tape having a pressure-sensitive adhesive layer made of a material for forming a pressure-sensitive adhesive layer containing such a polymerization initiator, even if the adherend is exposed to a high temperature in a state of being stuck, the pressure-sensitive adhesive force is hardly lowered. . In addition, the said weight decreasing rate can be calculated | required by measuring a weight using commercially available thermogravimetry apparatus, for example, DTG-60A by Shimadzu Corporation. Specifically, the polymerization initiator is analyzed (atmosphere gas: nitrogen, gas flow rate: 50 ml / min, temperature range: 30 to 190 ° C., temperature rising condition: 10 ° C./min), and the polymerization initiator at 30 ° C. , And the weight (W2) of the polymerization initiator after 30 minutes from reaching 190 ° C. can be measured and applied to the following equation.
Weight reduction rate (%) = [(W1 (g) −W2 (g)) / W1 (g)] × 100

  In addition, as a commercial item of the said polymerization initiator, IRGACURE754 (made by BASF Japan), IRGACURE2959 (made by BASF Japan), etc. are mentioned, for example.

  The content of the polymerization initiator in the pressure-sensitive adhesive layer forming material is preferably 0.01 to 10 parts by mass with respect to 100 parts by mass in total of the acrylic polymer and the energy ray polymerizable oligomer. It is more preferable that it is 5-3 mass parts. If it exists in the said range, the said energy beam polymerizable oligomer will fully harden | cure. When the amount is less than 0.01 parts by mass, the polymerization initiation reaction is not sufficient, the adhesive strength after irradiation with energy rays becomes excessively high, and proper peelability may not be realized. If it exceeds 10 parts by mass, the energy beam reaches only in the vicinity of the energy beam irradiation surface, and curing may be insufficient. In addition, the cohesive force is reduced, which may cause adhesive residue on the adherend. When the pressure-sensitive adhesive layer forming material contains the energy beam polymerizable oligomer and the energy beam polymerizable monomer, the acrylic polymer, the energy beam polymerizable oligomer, and the energy beam polymerizable monomer are used. It is preferable that it is 0.01-10 mass parts with respect to a total of 100 mass parts, and it is more preferable that it is 0.5-3 mass parts.

(Crosslinking agent)
In the adhesive tape of this invention, a crosslinking agent is contained as an adhesive layer forming material. A crosslinking agent is not specifically limited, For example, an isocyanate type crosslinking agent, an epoxy-type crosslinking agent, etc. are mentioned. As an isocyanate type crosslinking agent, for example, a polyisocyanate compound, a trimer of a polyisocyanate compound, a urethane prepolymer having a terminal isocyanate group obtained by reacting a polyisocyanate compound and a polyol compound, 3 of the urethane prepolymer Examples include a polymer. Examples of the polyisocyanate compound include 2,4-tolylene diisocyanate, 2,5-tolylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, diphenylmethane-4,4′-diisocyanate, 3 -Methyldiphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, dicyclohexylmethane-2,4'-diisocyanate, lysine isocyanate and the like.

  Examples of the epoxy-based crosslinking agent include sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, diglycerol polyglycidyl ether, glycerol polyglycidyl ether, trimethylolpropane polyglycidyl ether, neopentyl glycol diester. Examples include polyfunctional epoxy compounds such as glycidyl ether, 1,6-hexanediol diglycidyl ether, hydrogenated bisphenol A diglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, and polybutadiene diglycidyl ether.

  The crosslinking agent can be used alone or in combination of two or more, and may be appropriately selected according to the type of the acrylic polymer.

  In addition, as a commercial item of the said isocyanate type crosslinking agent, L45 (made by Soken Chemical Co., Ltd.), TD75 (made by Soken Chemical Co., Ltd.), BXX5627 (made by Toyo Ink Manufacturing Co., Ltd.), X-301-422SK (Siden), for example. (Made by Kagaku Co., Ltd.) etc. can be used suitably. Moreover, as a commercial item of the said epoxy-type crosslinking agent, E-5XM (made by Soken Chemical Co., Ltd.), E-5C (made by Soken Chemical Co., Ltd.) etc. can be used suitably, for example.

  The content of the crosslinking agent in the pressure-sensitive adhesive layer forming material varies depending on the type of the crosslinking agent. For example, in the case of an isocyanate-based crosslinking agent, 0.01 to 15 with respect to 100 parts by mass of the acrylic polymer. It is preferable that it is a mass part, and it is more preferable that it is 0.01-10 mass parts. If it is the said range, the adhesiveness of an adhesive layer and a base material can be improved. When less than 0.01 parts by mass, the adhesiveness between the pressure-sensitive adhesive layer and the substrate becomes insufficient, or it becomes difficult for the pressure-sensitive adhesive layer to have sufficient strength, and when it peels from the adherend In some cases, the pressure-sensitive adhesive layer causes cohesive failure to cause adhesive residue. If it exceeds 15 parts by mass, it remains as an unreacted monomer in the pressure-sensitive adhesive layer, and the cohesive force may be reduced.

  Moreover, in the case of an epoxy type crosslinking agent, it is preferable that it is 0.01-15 mass parts with respect to 100 mass parts of said acrylic polymers, and it is more preferable that it is 0.01-10 mass parts. If it is the said range, the adhesive force and cohesion force before energy ray irradiation can be controlled to desired intensity | strength. If it is less than 0.01 parts by mass, it is difficult for the pressure-sensitive adhesive layer to have sufficient strength, and the pressure-sensitive adhesive layer may cause cohesive failure when peeled off from the adherend, resulting in adhesive residue. If it exceeds 15 parts by mass, the adhesive strength before irradiation with energy rays is reduced, so that the chemical solution may permeate between the pressure-sensitive adhesive layer and the non-adherent or air may enter. Further, the adherend cannot be sufficiently held during cutting, and a defective product may be generated.

  In addition, the pressure-sensitive adhesive composition of the present invention includes a silane coupling agent, a tackifier, a metal chelating agent, a surfactant, an antioxidant, and an ultraviolet absorber as long as the object of the present invention is not impaired. Various additives such as pigments, dyes, colorants, antistatic agents, preservatives, antifoaming agents, and wettability adjusting agents can be blended.

  The thickness of the pressure-sensitive adhesive layer is usually 5 to 50 μm, preferably 10 to 30 μm. If it is in the said range, adhesive physical property will be stabilized. If the thickness is less than 5 μm, sufficient adhesive strength may not be obtained. If the thickness exceeds 50 μm, the energy rays are not sufficiently transmitted to the inside of the pressure-sensitive adhesive layer, and the adhesive strength is reduced by irradiation with energy rays. It may not decrease. In addition, excessive performance may increase costs.

When a 10 μm-thick pressure-sensitive adhesive layer made of the pressure-sensitive adhesive layer forming material is formed on a heat-resistant substrate having a thickness of 50 μm, the surface free energy is 30 to 50 mJ / m ² , and the arithmetic average After 20 minutes have passed since the 180 ° peel-off adhesive strength (based on JIS Z0237) of the pressure-sensitive adhesive layer to the polyimide resin surface having a roughness Ra of 0.4 to 0.6 μm is pasted on the polyimide resin surface, 0 0.8 to 15 N / 25 mm, 0.8 to 20 N / 25 mm after heating at 150 ° C. for 90 minutes, and 0.4 N / 25 mm or less after curing by irradiation with energy rays after the heating. It is preferable that it is 0.8 to 10 N / 25 mm after 20 minutes have elapsed after being pasted on the polyimide resin surface, and 0.8 to 15 N / 2 after heating at 150 ° C. for 90 minutes. It is more preferably 0.4 N / 25 mm or less after curing by irradiation with energy rays after heating.

  If it is within the above range, the initial adhesive strength to the polyimide resin surface is sufficiently high, and it does not peel off from the adherend even under high temperature conditions during the manufacturing process of the electronic component. Can be easily peeled off without any adhesive residue. In addition, a universal material testing machine (type 5565, manufactured by Instron Japan) can be used as the measuring device.

  In addition, the surface free energy of a polyimide resin surface first measures the contact angle of ethylene glycol, water, and a methylene iodide by the method based on JISK2396 using a contact angle meter. And surface free energy is computed from the obtained value and the theory of Kitazaki-Hata. As the contact angle meter, for example, a FACE contact angle meter CA-D type manufactured by Kyowa Interface Science Co., Ltd. can be suitably used.

  In addition, the arithmetic average roughness (Ra) of the polyimide resin surface is measured by a method based on JIS B0601-2001 using an atomic force microscope. As the atomic force microscope, for example, Nanopics-1000 manufactured by Seiko Instruments Inc. can be suitably used.

When using ultraviolet rays as energy rays, for example, using a high-pressure mercury lamp, ultrahigh-pressure mercury lamp, carbon arc lamp, metal halide lamp, xenon lamp, chemical lamp, etc. Irradiation may be performed so as to be 50 mJ / cm ² or more, preferably 200 mJ / cm ² or more.

[Peeling layer]
The pressure-sensitive adhesive tape of the present invention preferably has a release layer. A peeling layer means the peeling sheet which consists of a peeling member which has peelability, and has the function to protect the surface of an adhesive layer. The release member is not particularly limited as long as it has the required strength and flexibility, and generally a synthetic resin film subjected to silicone release treatment is used. As a material for the synthetic resin film, for example, polyester resins such as polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, polybutylene naphthalate, polyarylate, polytetramethylene terephthalate are preferable. Although the thickness of a peeling layer is not specifically limited, Preferably it is 25-100 micrometers.

  The manufacturing method of the adhesive tape of this invention is not specifically limited, A conventionally well-known method can be used. For example, the pressure-sensitive adhesive can be obtained by dissolving or dispersing the acrylic polymer, the energy beam polymerizable oligomer, the polymerization initiator, the crosslinking agent, and, if necessary, the various additives in an organic solvent. A layer forming coating solution is obtained. Next, the entire surface of the coating solution is coated on the heat-resistant substrate with an applicator or the like to form an adhesive layer. Thereafter, the pressure-sensitive adhesive layer is dried, and a peelable synthetic resin film or the like is laminated, whereby the pressure-sensitive adhesive tape of the present invention can be formed. Although it does not specifically limit as an organic solvent, For example, toluene, methyl ethyl ketone, ethyl acetate, dimethylacetamide, these mixed solutions, etc. can be used conveniently.

  The method for coating the coating solution on the heat-resistant substrate is not particularly limited, and a conventionally known method can be used. Examples of the forming method by printing include a gravure printing method, a flexographic printing method, and an offset printing method. Examples of the coating method include roll coating, reverse coating, comma coating, knife coating, die coating, and gravure coating.

  Although the thickness of the adhesive tape of this invention is not specifically limited, It is preferable that it is 80-350 micrometers, and it is more preferable that it is 90-140 micrometers. If it is the said range, since it has moderate softness | flexibility, handling becomes easy.

  The sticking target of the adhesive tape of the present invention is an electronic component such as a semiconductor or a substrate having a polyimide resin surface, and includes an electronic component made of polyimide resin. According to the adhesive tape of the present invention, the initial adhesive force on the polyimide resin surface is high, and even when exposed to high temperatures, the adhesive force is not easily lowered, and has an adhesive force necessary for fixation and protection, Furthermore, when removing and removing, since it can be easily peeled off without leaving any glue by a simple operation of irradiating energy rays, appropriate fixing and protection are required during the process. It is suitable as a process tape that involves use under high temperature conditions for peeling off. Specifically, it is suitable as an adhesive tape used for temporarily fixing or surface-protecting components in a printed wiring board manufacturing process. As a method for using the pressure-sensitive adhesive tape of the present invention, for example, the pressure-sensitive adhesive tape of the present invention is attached to the polyimide resin surface of an electronic component to be attached. The adhesive tape is then cured by irradiating it with energy rays such as ultraviolet rays from the substrate side of the adhesive tape when it is no longer necessary to be fixed or protected after steps such as heat treatment, processing, and chemical treatment. Is removed from the polyimide resin surface of the electronic component.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention does not receive a restriction | limiting at all by these description.

<Example 1>
UV curable acrylic pressure-sensitive adhesive (trade name: N-4498, acrylic polymer + energy ray polymerizable oligomer, mass average molecular weight of acrylic polymer: about 400,000, energy ray polymerizable oligomer: polyurethane acrylate oligomer, acrylic polymer The polymerization initiator (trade name: IRGACURE 754, photoradical generator) with respect to 100 parts by mass of the hydroxyl group-containing monomer and carboxyl group-containing monomer in mass: 30/1, solid content: 40%, manufactured by Nippon Synthetic Chemical Co., Ltd. , Solid content: 100%, manufactured by BASF Japan) 1.4 parts by mass, and 1.5 parts by mass of a crosslinking agent (trade name: Coronate L, isocyanate-based crosslinking agent, solid content: 75%, manufactured by Nippon Polyurethane Co., Ltd.) Part of the mixture, toluene and methyl ethyl ketone mixed solvent (trade name: KT11, mass ratio 1: 1, manufactured by DIC Graphics Corporation) was diluted with 180 parts by mass and sufficiently dispersed to prepare a coating solution for forming an adhesive layer.

The above polymerization initiator was analyzed using a thermogravimetric measuring device (product name: DTG-60A, manufactured by Shimadzu Corporation) (atmosphere gas: nitrogen, gas flow rate: 50 ml / min, temperature range: 30 to 190 ° C., Temperature rise condition: 10 ° C./min, measurement sample amount: 32.5 mg), the weight of the polymerization initiator at 30 ° C. (W1), and the polymerization initiator after 30 minutes from reaching 190 ° C. The weight reduction rate was calculated from the weight (W2) by the following formula, and the value was 12%.
Weight reduction rate (%) = [(W1 (g) −W2 (g)) / W1 (g)] × 100

  Next, the base material (biaxially stretched polyester film, trade name: Lumirror S56, heat shrinkage (conforming to JIS C2151, 150 ° C. × 30 min): MD is 0.5%, TD is 0.3%, film thickness: 50 μm, The pressure-sensitive adhesive layer-forming coating solution was coated on the entire surface with an applicator so that the film thickness after drying was 10 μm. Then, it was made to dry and the peeling sheet (PET separator, brand name: SP-PET-01, film thickness: 38 micrometers, the product made by Tosero) was laminated, and the adhesive tape of Example 1 was obtained.

<Example 2>
UV curable acrylic pressure-sensitive adhesive (trade name: N-7257, acrylic polymer + energy ray polymerizable oligomer, mass average molecular weight of acrylic polymer: about 400,000, energy ray polymerizable oligomer: polyurethane acrylate oligomer, acrylic polymer The polymerization initiator (trade name: IRGACURE 754, photoradical generator) with respect to 100 parts by mass of the hydroxyl group-containing monomer and carboxyl group-containing monomer in mass: 3/1, solid content: 41%, manufactured by Nippon Synthetic Chemical Co., Ltd. , Solid content: 100%, manufactured by BASF Japan) 1.4 parts by mass, and 2 parts by mass of crosslinking agent (trade name: Coronate L, isocyanate-based crosslinking agent, solid content: 75%, manufactured by Nippon Polyurethane) And a mixed solvent of toluene and methyl ethyl ketone (trade name: KT11, mass ratio 1: 1) , Manufactured by DIC Graphics Co., Ltd.) The pressure-sensitive adhesive tape of Example 2 was prepared in the same manner as in Example 1 except that it was diluted with 186 parts by mass and sufficiently dispersed to prepare a coating solution for forming an adhesive layer. Got.

<Comparative Example 1>
Acrylic adhesive (trade name: SK Dyne SW-2B, acrylic polymer, mass average molecular weight of acrylic polymer: about 200,000, mass ratio of hydroxyl group-containing monomer to carboxyl group-containing monomer in acrylic polymer: 1/10 , Solid content: 45%) 12 parts by mass of an energy ray polymerizable oligomer (trade name: UV7600B, polyurethane acrylate oligomer, solid content: 100%, manufactured by Nippon Synthetic Chemical Co., Ltd.) Product name: IRGACURE 184, photoradical generator, solid content: 100%, BASF Japan Ltd.) 1.3 parts by mass, and crosslinking agent (trade name: E-5XM, epoxy-based crosslinking agent, solid content: 5%, 7 parts by mass of Soken Chemical Co., Ltd., and crosslinking agent (trade name: L-45, isocyanate crosslinking agent, solid content 45%, day 2.7 parts by mass of polyurethane), diluted with 100 parts by mass of a mixed solvent of toluene and methyl ethyl ketone (trade name: KT11, mass ratio 1: 1, manufactured by DIC Graphics), and sufficiently dispersed. A pressure-sensitive adhesive tape of Comparative Example 1 was obtained in the same manner as in Example 1 except that the pressure-sensitive adhesive layer-forming coating solution was prepared. In addition, when the weight reduction rate (measurement sample amount: 14.2 mg) of the polymerization initiator was determined by the same method as in Example 1, it was 100%.

<Comparative example 2>
Acrylic adhesive (trade name: SK Dyne SW-2B, acrylic polymer, mass average molecular weight of acrylic polymer: about 200,000, mass ratio of hydroxyl group-containing monomer to carboxyl group-containing monomer in acrylic polymer: 1/10 , Solid content: 45%) 12 parts by mass of an energy ray polymerizable oligomer (trade name: UV7600B, polyurethane acrylate oligomer, solid content: 100%, manufactured by Nippon Synthetic Chemical Co., Ltd.) Product name: IRGACURE184, photoradical generator, solid content: 100%, BASF Japan Ltd.) 1.3 parts by mass, crosslinking agent (trade name: E-5XM, epoxy crosslinking agent, solid content: 5%, Soken 7 parts by mass of Chemical Co., Ltd., and a crosslinking agent (trade name: L-45, isocyanate crosslinking agent, solid content 45%, Nippon 7 parts by mass of Urethane Co., Ltd., diluted with 100 parts by mass of a mixed solvent of toluene and methyl ethyl ketone (trade name: KT11, mass ratio 1: 1, manufactured by DIC Graphics), fully dispersed, and adhesive A pressure-sensitive adhesive tape of Comparative Example 2 was obtained in the same manner as in Example 1 except that the layer-forming coating solution was prepared.

  The adhesive tapes obtained in Examples 1 and 2 and Comparative Examples 1 and 2 were evaluated for adhesive strength and checked for the presence of adhesive residue.

[Adhesive strength evaluation]
The adhesive tapes obtained in Examples 1 and 2 and Comparative Examples 1 and 2 were cut into a width of 25 mm and a length of 100 mm to prepare test pieces. For the evaluation of adhesive strength, a polyimide film (trade name: Kapton 200H, film thickness: 50 μm, manufactured by Toray DuPont) was used. First, the surface free energy and arithmetic average roughness (Ra) of the polyimide film were measured.

The surface free energy of the polyimide film is measured with a contact angle meter (product name: FACE contact angle meter CA-D type, manufactured by Kyowa Interface Science Co., Ltd.) for ethylene glycol, water, and methylene iodide (JIS K2396 compliant). And calculated from the measured value and the theory of Kitazaki-Hata. As a result, the surface free energy of the polyimide film was 47.4 mJ / m ² .

  In addition, the arithmetic average roughness (Ra) of the polyimide film was measured by a method based on JIS B0601-2001. Specifically, the measurement was performed under the following conditions. As a result, the arithmetic average roughness (Ra) of the polyimide film was 0.53.

<Measurement conditions>
Equipment used: Atomic force microscope (Product name: NanoScope V MultiMode, probe: MPP-11100-10, manufactured by Veeco)
Used scanner: J-scanner
Measurement mode: TM-AFM
Scanning range: 1.0 × 1.0μm
Resolution: 1024 × 1024
Scan rate: 0.5 Hz

(Initial adhesion measurement)
The release sheet of the test piece was peeled off, laminated to the polyimide film using a 2 kg roller, and allowed to stand at room temperature and humidity for 20 minutes. Then, using a universal material testing machine (model 5565, manufactured by Instron Japan), the initial adhesive strength was measured (JIS Z0237 compliant, peeling speed: 300 mm / min, peeling distance: 50 mm, peeling angle: 180 °). . The results are shown in Table 1.

  In addition, the evaluation criteria of initial adhesive strength are as follows. ○: Within the range of 0.8 to 15 N / 25 mm, x: less than 0.8 N / 25 mm, or more than 15 N / 25 mm.

(Measurement of adhesive strength after heat treatment)
The release sheet of the test piece was peeled off, laminated to the polyimide film using a 2 kg roller, and allowed to stand at room temperature and humidity for 20 minutes. Next, after heating at 150 ° C. for 90 minutes, the adhesive strength after the heat treatment is measured using a universal material testing machine (model 5565, manufactured by Instron Japan) (JIS Z0237 compliant, peeling rate: 300 mm / min). , Peeling distance: 50 mm, peeling angle: 180 °). The results are shown in Table 1.

  In addition, the evaluation criteria of the adhesive force after heat processing are as follows. ○: Within the range of 0.8 to 20 N / 25 mm, x: less than 0.8 N / 25 mm, or more than 20 N / 25 mm.

(Measurement of adhesive strength after UV irradiation)
The release sheet of the test piece was peeled off, laminated on the polyimide film using a 2 kg roller, left at room temperature and humidity for 20 minutes, and then heated at 150 ° C. for 90 minutes. Next, after irradiating ultraviolet rays (integrated light amount: 200 mJ / cm ² ) using a fusion H / bulb lamp as a light source from the substrate side, a universal material testing machine (model 5565, manufactured by Instron Japan) was used. Then, the adhesive strength after ultraviolet irradiation was measured (according to JIS Z0237, peeling speed: 300 mm / min, peeling distance: 50 mm, peeling angle: 180 °). The results are shown in Table 1.

  In addition, the evaluation criteria of the adhesive strength after ultraviolet irradiation are as follows. ○: 0.4 N / 25 mm or less, ×: more than 0.4 N / 25 mm.

[Check for adhesive residue]
The adhesive tapes obtained in Examples 1 and 2 and Comparative Examples 1 and 2 were cut into a width of 25 mm and a length of 100 mm to prepare test pieces.
The release sheet of the test piece was peeled off, laminated on the polyimide film using a 2 kg roller, left at room temperature and humidity for 20 minutes, and then heated at 150 ° C. for 90 minutes. Next, after irradiating ultraviolet rays using a H / bulb lamp manufactured by Fusion as a light source from the substrate side (integrated light amount: 200 mJ / cm ² ), the test piece was peeled off (peeling speed: 300 mm / min, peeling distance: 50 mm, Peeling angle: 180 °) and the adhesive residue (width 1 mm or more) on the polyimide film surface was confirmed with an optical microscope (VHX-600, manufactured by Keyence Corporation, magnification 200). The results are shown in Table 1.

The adhesive tapes of Examples 1 and 2 showed good initial adhesive strength, and even when heat-treated, the adhesive strength did not decrease, and when peeled and removed, the adhesive tape was easily peelable. . Further, no adhesive residue was generated after peeling. From these results, it was confirmed that the adhesive tapes of Examples 1 and 2 have preferable physical properties as a tape for fixing or protecting an adherend having an etched polyimide resin surface.
On the other hand, the adhesive tapes of Comparative Examples 1 and 2 had low initial adhesive strength, and exhibited undesirable physical properties as a tape for fixing or protecting an adherend having a polyimide resin surface.

DESCRIPTION OF SYMBOLS 1 Base material 2 Adhesive layer 3 Release layer 10 Adhesive tape

Claims (3)

In the manufacturing process of electronic parts, a heat-resistant temporary wearing adhesive tape used for temporarily fixing or protecting a part having a polyimide resin surface,
A pressure-sensitive adhesive layer made of a pressure-sensitive adhesive layer-forming material containing an acrylic polymer, an energy beam polymerizable oligomer, a polymerization initiator, and a crosslinking agent is formed on the heat-resistant substrate,
The acrylic polymer has an acrylic ester as a main component and is obtained by copolymerization of the acrylic ester with a copolymerizable hydroxyl group-containing monomer, or has an acrylic ester as a main component, and the acrylic ester. , Obtained by copolymerization with a copolymerizable hydroxyl group and carboxyl group-containing monomer, the mass ratio of the hydroxyl group-containing monomer and the carboxyl group-containing monomer is 51:49 to 100: 0,
The polymerization initiator is allowed to warm from 30 ° C. at a heating rate 10 ° C. / min up to 190 ° C., Ri der weight reduction rate of 50% or less by thermogravimetry when maintained for 30 minutes at 190 ° C.,
Surface adhesive energy is 30-50 mJ / m ² and arithmetic average roughness Ra is 0.4-0.6 μm. 180 ° peeling adhesive strength of the adhesive layer to the polyimide resin surface (according to JIS Z0237) ) Is 0.8 to 15 N / 25 mm after 20 minutes have passed from the polyimide resin surface, 0.8 to 20 N / 25 mm after heating for 90 minutes at 150 ° C., and the cured by energy ray irradiation after heating, heat temporary wearing adhesive tape, characterized in der Rukoto below 0.4 N / 25 mm.   2. The heat-resistant temporary adhesive tape according to claim 1, wherein the heat-shrinkable base material has a heat shrinkage ratio (conforming to JIS C2151) of 1.0% or less in the MD direction and 1.0% or less in the TD direction. Claim 1 or the temporary adherend heat temporary wearing pressure-sensitive adhesive tape according becomes affixed to the 2.

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