CN103827241A

CN103827241A - Heat-releasable adhesive sheet for cutting electrical component and electrical component cutting method

Info

Publication number: CN103827241A
Application number: CN201280045943.5A
Authority: CN
Inventors: 平山高正; 下川大辅; 木内一之
Original assignee: Nitto Denko Corp
Current assignee: Nitto Denko Corp
Priority date: 2011-09-20
Filing date: 2012-09-20
Publication date: 2014-05-28
Also published as: JPWO2013042698A1; TW201319207A; JP6000958B2; TWI586783B; KR20140068972A; WO2013042698A1; KR101950051B1

Abstract

The present invention makes it possible to prevent the appearance of protrusions caused by heat-expandable microspheres atop a heat-releasable adhesive agent layer, using an energy ray-curable elastic layer and the heat-releasable adhesive agent layer. Further, causing the heat-expandable microspheres to be present across both the energy ray-curable elastic layer and the heat-releasable adhesive agent layer and thinning the heat-releasable adhesive agent layer allows for highly precise machining and prevents faulty machining caused by displacement of the electrical component during machining of the electrical component. Moreover, close adhesion between the base material and the energy ray-curable elastic layer is enhanced and adhesive peeling onto the work piece following release, i.e., adhesive deposition is prevented. In order to resolve the foregoing problems, provided is a heat-releasable adhesive sheet obtained by providing the heat-releasable adhesive agent layer containing heat-expandable microspheres to at least one side of the base material, with the energy ray-curable elastic layer interposed therebetween, wherein the heat-releasable adhesive sheet is characterized in including an organic coating layer between the base material and the energy ray-curable elastic layer.

Description

Electronic unit cuts off with heat-peelable pressure-sensitive adhesive sheet and electronic unit cutting-off method

Technical field

The present invention relates to electronic unit cuts off with heat-peelable pressure-sensitive adhesive sheet and electronic unit cutting-off method.

Background technology

Follow electronic unit in recent years, semi-conductive miniaturization, more in the past than the working accuracy of more pursuing machined object.Use in the working method of existing heat-releasable pressure-sensitive adhesive sheet, binder layer softness, and thick, therefore can not get sufficient working accuracy owing to adding the moving of tackiness agent that the stress in man-hour causes.

On the other hand, attenuate binder layer is effective, but when excessive thinning binder layer, the adhesive layer surface causing due to the particle of heat-expandable microsphere concavo-convex, produce the bad order of nipping and causing by bubble etc., and cannot obtain sufficient cementability, cannot bring into play as the fixing function with adhesive sheet.

Therefore, as recorded in patent documentation 1, known following method: utilize and clip the energy ray-curable thermally strippable adhesive sheet that the stacked thermal expansivity bonding coat that contains heat-expandable microsphere of energy ray-curable elastic layer forms on base material, electronic unit, semiconductor crystal wafer are fixed, add man-hour by energy ray-curable elastic layer solidify, thereby reduce the movement of the tackiness agent that adds man-hour, improve thus working accuracy, after processing, peel off parts are easily reclaimed by heating.

Prior art document

Patent documentation

Patent documentation 1: TOHKEMY 2002-121505 communique

Summary of the invention

the problem that invention will solve

But, about the existing energy ray-curable thermally strippable adhesive sheet using in the method, energy ray-curable elastic layer after solidifying and the adaptation of base material are insufficient, sometimes between energy ray-curable elastic layer and base material, local generation peeled off (fastening destruction), sometimes on adherend, produce cull, in addition, the cross section sometimes being obtained by cut-out operation, with respect to surperficial non-vertical, cannot cut off exactly.

for the scheme of dealing with problems

The inventor etc. peel off and conduct in-depth research for the anchoring of existing energy ray-curable thermally strippable adhesive sheet, result recent findings, utilize the chemically compatible method that improves between binder layer and base material and form the fine concavo-convex method that increases both contacts area etc. at substrate surface, be generally used for the method for adhesive sheet, cannot effectively prevent that above-mentioned anchoring from peeling off etc.In addition,, about the formation that can suppress efficiently for the thermally strippable adhesive sheet of the fastening destruction of this adhesive sheet, repeatedly experienced test and mistake, thereby completed the present invention.

, heat-releasable pressure-sensitive adhesive sheet of the present invention is as follows:

1. a heat-peelable pressure-sensitive adhesive sheet, it is characterized in that, its at least one side at base material clips the thermally strippable binder layer that the setting of energy ray-curable elastic layer contains heat-expandable microsphere and forms, and described heat-peelable pressure-sensitive adhesive sheet disposes organic coating between aforementioned substrates and energy ray-curable elastic layer.

2. heat-peelable pressure-sensitive adhesive sheet according to claim 1, aforementioned organic coating is formed by carbamate based polymer.

3. heat-peelable pressure-sensitive adhesive sheet according to claim 1 and 2, is characterized in that, the thickness of thermally strippable binder layer is below 50 μ m.

4. according to the heat-peelable pressure-sensitive adhesive sheet described in any one in claim 1～3, it is characterized in that, the thickness of energy ray-curable elastic layer is 3～150 μ m.

5. a cutting-off method for electronic unit, is characterized in that, utilizes in 1～4 the heat-peelable pressure-sensitive adhesive sheet described in any one that electronic unit is temporary fixed and cut off this electronic unit.

the effect of invention

According to the present invention, obtain as follows adhesive sheet: being caused by heat-expandable microsphere of producing concavo-convex fitted in for improving soft energy ray-curable elastic layer before the solidifying of working accuracy its absorption on the thin heat-releasable binder layer of the maximum particle diameter than adding heat-expandable microsphere, thereby manufacture the adhesive sheet with good outward appearance and surface smoothness, then the adhesive sheet of thickness of soft bonding coat (being now heat-releasable tackiness agent) that or be attached at after machined object energy ray-curable elastic layer is solidified, can obtain attenuate.And then, by using this adhesive sheet processing machined object, can process small parts with high precision.

In addition, according to the present invention, can suppress suppression process, cut off tackiness agent when operation skew, roll, fragmentation, can vertically cut off with this machined object surface.

And, after cut-out, the cut off machine cutting off after processing easily can be peeled off to recovery with high precision.Therefore, operability and the workability of the peeling off of cut off machine, recovery process can be significantly improved, and then the productivity of the cut off machine of semi-conductor chip, the cascade capacitor chip etc. of small-sized or thin layer can be significantly improved.

Accompanying drawing explanation

Fig. 1 is the schematic diagram that an example of heat-peelable pressure-sensitive adhesive sheet of the present invention is shown.

Fig. 2 is the schematic diagram that another example of heat-peelable pressure-sensitive adhesive sheet of the present invention is shown.

Fig. 3 is the schematic diagram that the operation that uses heat-peelable pressure-sensitive adhesive sheet processing electronic unit of the present invention is shown.

description of reference numerals

1 base material

2 organic coatings

3 energy ray-curable elastic layers

3a energy-ray irradiate after fixing elastic layer

4 heat-releasable binder layers

Heat-releasable binder layer after 4a heat treated

5 barrier films

6 bond layers

7 barrier films

8 adherends (being cut off body)

8a cut off machine

9 energy-rays

10 cut off line

Embodiment

Conduct in-depth research in order to address the above problem, its result, by using the adhesive sheet between base material and the heat-releasable binder layer that comprises heat-expandable microsphere with the elastic layer of energy ray-curable, can improve these problems.

In addition find, in order to improve working accuracy, process machined object with following adhesive sheet, by using this working method, can process small parts with high precision, thereby complete the present invention, wherein said adhesive sheet is: being caused by heat-expandable microsphere of producing on the heat-releasable binder layer thinner than the maximum particle diameter of heat-expandable microsphere concavo-convex fitted to soft energy ray-curable elastic layer before solidifying etc., thereby by its stacked absorption, manufacture thus the adhesive sheet with good outward appearance and surface smoothness, then or after being attached at machined object energy ray-curable elastic layer is solidified, attenuate the adhesive sheet of thickness of soft bonding coat (being now heat-releasable binder layer).

Below, according to Fig. 1, the structure of heat-peelable pressure-sensitive adhesive sheet of the present invention is described.

The thermally strippable sheet that adds of the present invention is characterised in that, its at least one side at base material clips the heat-releasable binder layer that the setting of energy ray-curable elastic layer contains heat-expandable microsphere and forms, and between base material and energy ray-curable elastic layer, disposes organic coating.This energy ray-curable elastic layer and this heat-releasable binder layer can be arranged at the one side of this base material, also can be arranged at two sides.

While being arranged at one side, also can form bond layer at the another side of this base material, when processing electronic unit, this heat-peelable pressure-sensitive adhesive sheet with this heat-releasable binder layer that is fixed with electronic unit is loaded to the Stage microscope in processing unit (plant), can utilize this base material another side bond layer and be fixed on Stage microscope.

Certainly, might not form this bond layer at the another side of base material, now, this heat-peelable pressure-sensitive adhesive sheet with this heat-releasable binder layer that is fixed with electronic unit is arranged to the fixing means of the Stage microscope of processing unit (plant), for example utilizes vacuum chuck etc. to be fixed to be also fine.

Then, each layer that forms heat-peelable pressure-sensitive adhesive sheet of the present invention is described.

[base material]

Base material 1, as the support substrate of organic coating 2, energy ray-curable elastic layer 3 etc., uses and has the stable on heating material that can not damage because of the heat treated of heat-releasable binder layer 4 level of mechanical properties.

As this base material 1, for example, can list plastics film, the sheet of polyester, ethylene series resin, polyvinyl chloride etc., but be not limited to them.

The cut-out means of the cutter that base material 1 preferably uses when cutting off adherend etc. have cuttability.In addition, use flexible polyolefins film or sheet etc. to possess in the situation of base material of thermotolerance and retractility as base material 1, when the cut-out operation of adherend, if cutting knife enters in the middle of base material, can expand thereafter base material, therefore be applicable between cut off machine, to produce the cut off machine way of recycling in gap.

And then, when being solidified, energy ray-curable elastic layer 3 uses energy-ray, and therefore base material 1, organic coating 2 (or heat-releasable binder layer 4 etc.) need to be made up of the material that can see through energy-ray more than specified amount.Base material 1 can be individual layer, can be also polylayer forest.In addition, the stripper that base material 1 use aftermentioned is suitable is implemented to surface treatment, at its treated side forming energy ray curing elastic layer, to the energy ray-curable thermal expansivity adhesive sheet irradiation energy ray obtaining, after this energy ray-curable elastic layer is solidified, base material 1 is peeled off, thus also can be by this energy ray-curable thermal expansivity adhesive sheet self thin layer.

The thickness of base material 1 can suitably be selected in the scope of not damaging the operability of each operations such as the peeling off of the cut-out of the laminating of adherend, adherend, cut off machine, recovery, workability, be generally 500 μ m following, be preferably 3～300 μ m left and right, 5～250 μ m left and right more preferably.

For the surface of base material 1, for improve with adjacency layer adaptation, retentivity etc., also can implement chemical treatment or the physical treatments such as usual surface treatment, such as chromic acid processing, ozone exposure, fire exposure, high-voltage electric shock exposure, ionizing rays processing, utilize the coating processing of silane coupling agent (such as aftermentioned adhesive substance) etc.

[organic coating]

Organic coating 2 need to be sealed at base material 1 well, and heating is peeled off rear energy ray-curable elastic layer fastening destruction is not occurred.

Whether fastening destruction occurs for example can be evaluated by the method for recording in following embodiment.By not there is not fastening destruction, thereby base material clips organic coating 2 by bonding more firmly with heating removable adhesive layer, therefore, while using heat-peelable pressure-sensitive adhesive sheet of the present invention, add thermally strippable good, can bring into play not producing that glue strips off, i.e. the effect of cull.

As long as organic coating 2 has these characteristics, use which kind of material all can.

For example, can use the various coating materials shown in document (plastics are coated with material (プラスチックハードコート material) II firmly, and CMC publishes, (2004)).Wherein, preferred carbamate based polymer.This is because carbamate based polymer shows excellent adaptation to base material, and energy ray-curable elastic layer (after especially solidifying) is shown to excellent anchoring.Especially, more preferably polyacrylic carbamate and polyester-polyurethane, their precursor.The coating of these materials on base material 1/be coated with easy grade, practicality, industrially can select multiple material, can obtain at an easy rate.

As polyacrylic carbamate and polyester-polyurethane, also (plastics are coated with material (プラスチックハードコート material) II, P17-21 firmly can to use document, CMC publishes,) and document (up-to-date polyurethane material and utilisation technology (up-to-date Port リウレタ Application material と ying Ji Intraoperative) (2004), CMC publish, (2005)) shown in any materials.They are by isocyanate-monomer and the polymkeric substance for example, forming containing the reaction mixture of alcohol hydroxyl group monomer (hydroxy acryl acid compounds or hydroxyl ester cpds).As further composition, can also comprise the chainextenders such as polyamines, anti-aging agent, oxidation stabilizer etc.

Polyacrylic carbamate and polyester-polyurethane can use the material by prepared by above-mentioned monomer reaction, also usually can use the material (reference literature: up-to-date polyurethane material and utilisation technology (up-to-date Port リウレタ Application material と ying Ji Intraoperative) that resin glue as coating material or China ink, coating is commercially available or use, P190, CMC publishes (2005)).As this urethane, can list " NB300 ", " ADECABONTITER (registered trademark) ", the commercially available product such as " TAKELAC (registered trademark) A/TAKENATE (registered trademark) A ", " the UC sealer " that DIC GRAPHICS CORPORATION manufactures that Mitsui Chemicals, Inc manufactures that ADEKA Co., Ltd. manufactures that the Co., Ltd. that refines large day manufactures.

Also can in this polymkeric substance, add pigment etc., make China ink, be printed in thin film layer and use.Now, for example, can use the polyurethane-modified resins such as polyurethane series vinyl-acetic ester-vinyl chloride copolymer (NB300 of Co., Ltd. refines large day), utilize this printing, can also improve the designability of adhesive sheet.

Especially, as polyacrylic carbamate and polyester-polyurethane, base material is shown the reason of good adaptation, can consider it is because the isocyanate prepolymer composition comprising as monomer and the hydroxyl, the carboxyl isopolarity functional group reactions that are present in substrate surface, form firmly key.

In addition, especially, the reason improving as the anchoring of solidifying rear and energy ray-curable elastic layer at energy-ray, supposition be because, when the irradiations such as ultraviolet ray, react with the free radical species that generate in energy ray-curable elastic layer near the free radical species that generate amino-formate bond, form firmly key (document: the structure/physical property of urethane and multifunction and application start (Port リウレタ Application Agencies divine force that created the universe と Gao Machine can change and び ying Zhan Open), p191-194, the (Ji Intraoperative Qing Reported Association of technical intelligence association meeting) (1999)).

Thickness to organic coating is not particularly limited, and for example, 0.1～10 μ m left and right is applicable to, and is preferably 0.1～5 μ m left and right, more preferably 0.5～5 μ m left and right.

[energy ray-curable elastic layer]

Energy ray-curable elastic layer 3 is containing being useful on the energy ray-curable compound (or energy ray-curable resin) of giving energy ray-curable, and has the visco-elasticity (with reference to the enlarged view of Fig. 1) that can relax the concavo-convex level of heat-expandable microsphere in the time of crimping heat-releasable binder layer 4.In addition, energy ray-curable elastic layer 3 preferably becomes elastomerics after energy-ray irradiates.From this point of view, preferably, energy ray-curable elastic layer 3 use utilize energy-ray reactive functional groups chemical modification female agent (tackiness agent), or by energy ray-curable compound (or energy ray-curable resin) compounding is formed to having the composition forming in elastic female agent.

As aforementioned female agent, for example, can use natural rubber, synthetic rubber or use them and the rubber series tackiness agent, silicon rubber or its tackiness agent that obtain; For example, by (methyl) alkyl acrylate [, C such as (methyl) acrylic acid methyl esters, ethyl ester, propyl ester, isopropyl ester, butyl ester, isobutyl ester, own ester, monooctyl ester, 2-ethylhexyl, different monooctyl ester, isodecyl ester, dodecyl ester _1-20alkyl ester etc.] homopolymer or multipolymer, should (methyl) alkyl acrylate [for example, vinylformic acid, methacrylic acid, methylene-succinic acid, toxilic acid, fumaric acid, maleic anhydride etc. contain the monomer of carboxyl or anhydride group with other monomer; The hydroxyl monomers such as (methyl) vinylformic acid 2-hydroxyl ethyl ester; Styrene sulfonic acids etc. are containing sulfonic group monomer; The phosphorous acidic group monomers such as 2-hydroxyethyl acryl phosphoric acid ester; The amide-containing monomers such as (methyl) acrylamide; The emulsion stabilities such as (methyl) acrylic-amino ethyl ester; (methyl) vinylformic acid methoxyl group ethyl esters etc. are containing alkoxyl group monomer; N-N-cyclohexylmaleimides etc. are containing imide monomer; The vinyl esters such as vinyl-acetic ester; NVPs etc. are containing vinyl heterocyclic compound; The styrenic monomers such as vinylbenzene, alpha-methyl styrene; The cyano-containing monomers such as vinyl cyanide; (methyl) glycidyl acrylates etc. are containing epoxy group(ing) acrylic monomer; The vinyl ether such as vinyl ether are monomer etc.] multipolymer form acrylic resin or its tackiness agent; Polyurethane series resin, its tackiness agent; Vinyl-vinyl acetate copolymers etc. have suitable viscoelastic organic viscoelastic body.In addition, as this mother's agent, use or congener composition identical with the tackiness agent that forms aftermentioned heat-releasable binder layer 4, thus can be by stacked well to energy ray-curable elastic layer 3 and heat-releasable binder layer 4 adaptations.In preferred female agent, comprise the adhesive substances such as acrylic adhesives.Female agent can be made up of a kind of composition, also can be made up of two or more compositions.

As the energy-ray reactive functional groups for chemical modification, for example, can list acryl, methacryloyl, vinyl, allyl group, alkynyl etc. and there is functional group of carbon-to-carbon multiple bond etc.These can use separately or combine two or more uses.About these functional groups, thereby generate free radical by the irradiation carbon-to-carbon multiple bond cracking of energy-ray, this free radical becomes cross-linking set, can form three-dimensional net structure.

Wherein, (methyl) acryl, from energy-ray being shown to higher reactivity, can the viewpoint of Selection and Constitute use isoreactivity, workability be preferred from multiple acrylic adhesives.

As by energy-ray reactive functional groups chemical modification the representational example of female agent, can list following polymkeric substance: by the monomer that comprises hydroxyl and/or carboxyl isoreactivity functional group [for example, (methyl) vinylformic acid 2-hydroxyl ethyl ester, (methyl) vinylformic acid etc.] and (methyl) alkyl acrylate copolymer, make to obtain thus containing in reactive functional groups acrylic polymers and molecule, have can with the group (isocyanate group of previous reaction functional group reactions, epoxy group(ing) etc.) and energy-ray reactive functional groups (acryl, methacryloyl etc.) compound [for example, (methyl) acryloxy ethylidene isocyanic ester ((meth) acryloyloxy ethylene isocyanate) etc.] reaction, thereby the polymkeric substance obtaining.

The aforementioned ratio containing the monomer that comprises reactive functional groups in reactive functional groups acrylic polymers is with respect to whole monomers, for example, be 5～40 % by weight, be preferably 10～30 % by weight.

In molecule, have and can with the consumption of the compound of the group of previous reaction functional group reactions and energy-ray reactive functional groups with respect to containing the reactive functional groups (hydroxyl, carboxyl etc.) in reactive functional groups acrylic polymers with aforementioned containing when reactive functional groups acrylic polymers reacts, for example, be 20～100 % by mole, be preferably 40～95 % by mole.In addition, for promote to have in molecule can with reacting the addition reaction of the compound of the group of previous reaction functional group reactions and energy-ray reactive functional groups and the reactive functional groups containing in reactive functional groups acrylic polymers, can also compounding organotin, the catalyzer such as organo-metallic based compound, amine compound such as organic zirconium.

As for making the curing energy ray-curable compound of energy ray-curable elastic layer 3 energy-rays, as long as can utilize visible ray, ultraviolet ray, electron beam homenergic ray to be just cured and to be not particularly limited, preferably can make the good material of three-dimensional network efficiency of the energy ray-curable elastic layer 3a after energy radiation exposure.Energy ray-curable compound can use separately one or combine two or more uses.

As the object lesson of energy ray-curable compound, for example can list Viscoat 295, tetramethylol methane tetraacrylate, pentaerythritol triacrylate, tetramethylol methane tetraacrylate, Dipentaerythritol monohydroxy five acrylate, dipentaerythritol acrylate, 1,4-butylene glycol diacrylate, 1,6 hexanediol diacrylate, polyethyleneglycol diacrylate etc.

As energy ray-curable compound, also can use energy ray-curable resin, as energy ray-curable resin, for example can list ester (methyl) acrylate that molecular end has (methyl) acryl, carbamate (methyl) acrylate, epoxy (methyl) acrylate, trimeric cyanamide (methyl) acrylate, acrylic resin (methyl) acrylate, molecular end has allylic mercaptan-alkene add-on type resin, light-initiated cationic polymerization type resin, poly-vinyl cinnamates etc. are containing cinnamoyl polymkeric substance, diazotization amino novolac resin and/or acid/acrylic amide type polymkeric substance etc. containing the polymkeric substance of photosensitivity reactive group or containing the oligopolymer of photosensitivity reactive group etc.And then, as the polymkeric substance that utilizes high-energy rays to react, can list epoxidized polybutadiene, unsaturated polyester, poly (glycidyl methacrylate), polyacrylamide, polyvinyl siloxane etc.It should be noted that, while using energy ray-curable resin, aforementioned female agent is not necessarily essential.

The compounding amount of energy ray-curable compound is for example 5～500 weight parts left and right, is preferably 15～300 weight parts, the scope of 20～150 weight parts left and right more preferably with respect to the female agent of 100 weight parts.In addition, about the postradiation dynamic elastic modulus of energy-ray of energy ray-curable elastic layer 3, be 5 × 10 20 ℃ of down cut storage moduluss ⁶～1 × 10 ¹⁰when Pa (frequency: 1Hz, sample: thickness 1.5mm film like), can have excellent cut-out workability concurrently and add thermally strippable.This storage modulus can be adjusted by the kind of suitable selection energy ray-curable compound, compounding amount, energy-ray illuminate condition etc.

In addition, can also be used in combination energy-ray polymerization promotor as required together with aforementioned energy-ray polymerization starter.

In energy ray-curable elastic layer 3, except mentioned component, compounding is for making the curing energy-ray polymerization starter of energy ray-curable compound and obtain the suitable additive such as suitable viscoelastic thermal polymerization, linking agent, tackifier, vulcanizing agent and then weighting agent, anti-aging agent, antioxidant, tinting material before and after solidifying at energy-ray as required.

As energy-ray polymerization starter, can suitably select known and/or usual polymerization starter according to the kind of used energy-ray.

While carrying out polymerizable/curable as energy-ray with ultraviolet ray, comprise Photoepolymerizationinitiater initiater in order to be cured.As Photoepolymerizationinitiater initiater, be not particularly limited, for example can list benzoin methylether, benzoin iso-propylether, 2,2-dimethoxy-1, the benzoin ether such as 2-diphenylethane-1-ketone; Phenylmethylethers etc. replace benzoin ether; 2,2-diethoxy acetophenone, 2, the substituted acetophenones such as 2-dimethoxy-2-phenyl methyl phenyl ketone, 1-hydroxyl-cyclohexyl-phenyl ketone; 2-methyl-2-hydroxypropiophenonepreparations etc. replace α keto-alcohol; The aromatic sulfonyl such as 2-naphthalic sulfonic chloride; 1-phenyl-1,1-propanedione-2-(O-ethoxy carbonyl)-photolytic activity oximes such as oxime; The acylphosphine oxides such as 2,4,6-trimethylbenzoyl-phenylbenzene-phosphine oxide, two (2,4,6-trimethylbenzoyl)-phenyl phosphine oxide etc.

Energy ray-curable elastic layer 3 for example can form by following conventional process: the coating fluid that comprises energy ray-curable resin or female agent, energy-ray polymerizable compound and energy-ray polymerization starter and additive, solvent etc. is as required applied to the method on base material 1; At the aforementioned coating fluid of the upper coating of suitable barrier film (interleaving paper etc.), forming energy ray curing elastic layer 3, by its transfer printing (transfer) to the method on base material 1 etc.

When this energy ray-curable elastic layer is solidified, in the time that worry can produce caused by oxygen polymerization retardation, can on the mixture of coating urethane polymer on barrier film and free radical polymerization monomer, load the sheet that lift-off processing crosses and block oxygen, also base material can be put in the container that is filled with non-active gas and reduced oxygen concentration.

The kinds of the lamp that can suitably select the kind of energy-ray etc., use in irradiating etc., can be used the high-voltage lamps such as the low-voltage lamps such as fluorescence chemical lamp, black lamp, germicidal lamp, metal halide lamp, high voltage mercury lamp etc.And then the irradiation dose of ultraviolet ray etc. can be set arbitrarily according to the characteristic of required energy ray-curable elastic layer.

The viewpoint such as concavo-convex, the vibration that caused by rotating blade while preventing from cutting off adherend of contained heat-expandable microsphere from relax heat-releasable binder layer 4, the thickness of energy ray-curable elastic layer 3 is 3～150 μ m left and right, be preferably 5～150 μ m, more preferably 10～150 μ m left and right, 15～100 μ m left and right more preferably.

[heat-releasable binder layer]

Heat-releasable binder layer 4 comprises for giving fusible adhesive material and for giving the heat-expandable microsphere of thermal expansivity.

Heat-releasable binder layer 4 be the foaming of the heat-expandable microsphere by being caused by heat reduce bond area make to peel off become be easy to layer.Heat-expandable microsphere can use separately or combine two or more uses.The median size of heat-expandable microsphere is preferably 1 μ m～25 μ m left and right.More preferably 5 μ m～15 μ m, are particularly preferably 10 μ m left and right.In addition, the maximum particle diameter of heat-expandable microsphere is greater than its median size.

As heat-expandable microsphere, can in the middle of known heat-expandable microsphere, suitably select.As heat-expandable microsphere, the heat-expandable microsphere of micro encapsulation cannot stably not show good separability sometimes, therefore, can use micro encapsulation aptly heat-expandable microsphere.

In addition, as the enlarged view shown in the right figure of Fig. 1, the surface smoothing of heat-releasable binder layer 4 and the concavo-convex of shape without the contained heat-expandable microsphere of reflection is desirable.Even in the time that heat-expandable microsphere due to compared with large exists in the thickness of the layer that makes heat-expandable microsphere cannot be accommodated in thermally strippable binder layer 4, be desirable by the protuberance of this heat-expandable microsphere is embedded into making the surface smoothing of thermal expansion type bonding coat 4 in the layer of energy ray-curable elastic layer.

As aforementioned adhesion material, use and there is the elastic material that allows and do not restrict the foaming of heat-expandable microsphere and/or the level of expansion in the time of heating.Therefore, can use existing known pressure adhesive (tackiness agent) etc.As pressure adhesive, for example, can exemplify the rubber series such as natural rubber, various synthetic rubber pressure adhesive; Silicon-type pressure adhesive; (methyl) alkyl acrylate and can for example, with the acrylic acid or the like pressure adhesive such as the multipolymer of other unsaturated monomer of this ester copolymerization (acrylic adhesives of, recording as female agent of aforementioned energy ray-curable elastic layer 3 etc.) etc.In addition, in heat-releasable binder layer 4, can also use energy ray-curable tackiness agent.Now, about the postradiation dynamic elastic modulus of energy-ray, in the temperature range that starts to expand at heat-expandable microsphere, storage shear modulus is 1 × 10 ⁵～5 × 10 ⁷when Pa (frequency: 1Hz, sample: thickness 1.5mm film like), can obtain good separability.

As heat-expandable microsphere, for example, can be that Trimethylmethane, propane, pentane etc. are easily gasified and are contained in and have the microballoon obtaining in elastic shell in the material expanding because of heating.Aforementioned shell conventionally by thermoplastic material, thermally melting material, the material that breaks because of thermal expansion etc. forms.As the material that forms aforementioned shell, for example, can list vinylidene chloride-acrylonitrile copolymer, polyvinyl alcohol, polyvinyl butyral, polymethylmethacrylate, polyacrylonitrile, polyvinylidene dichloride, polysulfones etc.Heat-expandable microsphere can utilize customary way, such as coacervation, interfacial polymerization etc. to manufacture.As heat-expandable microsphere, for example, also can utilize the commercially available products such as Matsumoto Microsphere (trade(brand)name, Matsumoto Yushi-Seiyaku Co., Ltd. manufactures).

The median size of heat-expandable microsphere, from viewpoints such as dispersiveness, thin layer formatives, is generally 1～80 μ m left and right, is preferably 3～50 μ m left and right.In addition, as heat-expandable microsphere, in order to reduce well the bounding force of the heat-releasable binder layer that comprises tackiness agent by heat treated efficiency, preferably have until cubical expansivity reaches 5 times of above, microballoons of 10 times of appropriate intensity of still not breaking above particularly preferably.In addition,, use the heat-expandable microsphere breaking under low thermal expansion time, while using the thermal expansion agent of micro encapsulation not, heat-releasable binder layer 4 cannot fully reduce with the bond area of adherend, is difficult to obtain good separability.

The consumption of heat-expandable microsphere is according to its kind and difference, with respect to tackiness agent basis polymkeric substance 100 weight parts that form heat-releasable binder layer 4, for example, is 10～200 weight parts, is preferably 20～125 weight parts left and right.When less than 10 weight part, efficient bounding force reduction after heat treated easily becomes insufficient, in addition, while exceeding 200 weight part, easily produce the interfacial failure of cohesive failure, energy ray-curable elastic layer 3 and the heat-releasable binder layer 4 of heat-releasable binder layer 4.

In heat-releasable binder layer 4, except tackiness agent, heat-expandable microsphere, all right compounding linking agent (for example, isocyanate-based linking agent, epoxy are linking agent etc.), the suitable additive such as tackifier (for example, multi-functional epoxy compounds or isocyanate compound, aziridine cpd, melamine resin, urea resin, anhydrous compound, polyamines, carbonyl bearing polymer etc.), softening agent, pigment, weighting agent, anti-aging agent, tensio-active agent, static inhibitor.

The formation of heat-releasable binder layer 4 can utilize following method to carry out: for example, the coating fluid that comprises tackiness agent, heat-expandable microsphere and additive, solvent etc. is as required coated directly onto on energy ray-curable elastic layer 3, clips the method that barrier film 5 carries out crimping; On suitable barrier film (interleaving paper etc.) 5, be coated with aforementioned coating fluid, form heat-releasable binder layer 4, by its crimping transfer printing (transfer) to suitable methods such as the methods on energy ray-curable elastic layer 3.

This barrier film 5 is to form peeling agent layer as required and the sheet that obtains in the one side of base material film, be also upper layer the sheet being stripped from for upper layer is exposed before use of protection heat-peelable pressure-sensitive adhesive sheet of the present invention and while forming heat-releasable binder layer 4 as the sheet of substrate.

As the base material film of barrier film, can use known film, for example can be from polyether-ether-ketone, polyetherimide, polyarylester, PEN, polyethylene film, polypropylene film, polybutene film, polyhutadiene film, poly-methyl pentene film, polyvinyl chloride film, vinyl chloride copolymer film, pet film, polybutylene terephthalate film, polyurethane film, vinyl-vinyl acetate copolymer film, ionomer resin film, ethene-(methyl) acrylic copolymer film, ethene-(methyl) acrylate copolymer film, polystyrene film, and select in the plastics film such as polycarbonate film etc.

Operable peeling agent layer is to select to contain the layer that the known strippers such as the silicone resin series stripping agent fluoridized, fluoro-resin series stripping agent, silicone resin series stripping agent, polyvinyl alcohol resin, polypropylene-based resin, long chain alkyl compound form according to the resin of binder layer.

The reduction performances of the bounding force that the thickness of heat-releasable binder layer 4 can obtain according to the application target of adhesive sheet, utilization heating etc. are suitably definite, in order to improve the processibility of machined object, and preferably its thin thickness.Therefore, the thickness of heat-releasable binder layer 4 is below 50 μ m, is preferably below 25 μ m, more preferably below 10 μ m.The thickness of heat-releasable binder layer 4 is 50 μ m when following, and the deflection of binder layer reduces, and processibility precision improves.And then, during by processing electronic unit, pressing force, shearing force are applied in this electronic unit, these power also can be conducted by thermotropism removable adhesive layer 4, but the thin thickness of heat-releasable binder layer 4, therefore can resist the power that this is applied in, thereby heat-peelable pressure-sensitive adhesive sheet of the present invention can keep this electronic unit reliably.

The thickness of heat-releasable binder layer 4 is that 50 μ m are when following, to utilizing the machined object that heat-peelable pressure-sensitive adhesive sheet of the present invention has been fixed to add man-hour, can not make the distortion quantitative change of binder layer large because of the pressing force for being caused with member by processing such as cutting knifes etc., can prevent the position of this machined object, towards even slightly change, result can be processed exactly.

In addition, the thickness of heat-releasable binder layer 4 be made as 1 μ m above, be preferably made as that 3 μ m are above, to be further preferably made as 5 μ m be preferred above.Be more than 1 μ m by the thickness of thermally strippable binder layer 4, there is the bounding force that can fix fully adherend, therefore for example can in the time cutting off, chip can not occur and process with dispersing.

As barrier film 5, for example, can use by the base material that utilizes the plastics film, the paper etc. that have carried out surface coated take silicon-type resin, chain alkyl acrylic ester resin, fluorine resin etc. as the stripper of representative to form; Or the base material that the binding property being made up of the non-polar polymer such as polyethylene, polypropylene is little etc.

Barrier film 5 as mentioned above can be as temporary support when crimping transfer printing (transfers) heat-releasable binder layer 4 on energy ray-curable elastic layer 3, in addition can be as protecting heat-releasable binder layer 4 until for practical protecting materials.

In addition, energy ray-curable elastic layer 3 and the heat-releasable binder layer 4 arranging thereon not only can form in the one side of base material 1, can also form on two sides.In addition, also can set gradually energy ray-curable elastic layer 3 and heat-releasable binder layer 4 at of base material 1 face, at another face, common bond layer is set.In addition, for prevent heat tracing process time heat-releasable binder layer 4 deformation of unevenness and small cohesive failure that occur and bonding interface adherend place also can further arrange bonding coat on this heat-releasable binder layer 4.As the adhesive substance of this bonding coat, can use the tackiness agent of recording in aforementioned hot removable adhesive layer 4.The thickness of this bonding coat is from the viewpoint of minimizing and even the forfeiture of the bounding force to adherend, is preferably 0.1～8 μ m, is especially 1～5 μ m, can utilize according to the method for thermal expansivity bonding coat 4 and form.

Fig. 2 is the schematic cross-section that another example of heat-peelable pressure-sensitive adhesive sheet of the present invention is shown.In this example, stack gradually organic coating 2, energy ray-curable elastic layer 3, heat-releasable binder layer 4 and barrier film 5 at a face of base material 1, and be laminated with bond layer 6 and barrier film 7 at another face of base material 1.This adhesive sheet base material 1 be formed with energy ray-curable elastic layer 3 and on the face of the contrary side of face of heat-releasable binder layer 4 on be provided with bond layer 6 and barrier film 7, only different from the adhesive sheet of Fig. 1 on the one hand at this.

Bond layer 6 comprises adhesive material.As this adhesive material, can use the material same with adhesive material (tackiness agent) in aforementioned hot removable adhesive layer 4, compounding linking agent (for example as required, isocyanate-based linking agent, epoxy are linking agent etc.), the suitable additive such as tackifier (for example, rosin derivative resin, polyterpene resin, petroleum resin, soluble phenolic resin etc.), softening agent, weighting agent, anti-aging agent, tensio-active agent.But use or interpolation obviously hinder and make the material seeing through of the curing energy-ray of energy ray-curable elastic layer 3 is not preferred.

The thickness of bond layer 6 can suitably be set in the scope of operability etc. of not damaging the peeling off of the cut-out of the crimping of heat-releasable binder layer 4 to adherend, adherend and cut off machine, recovery etc., is generally 1～50 μ m, is preferably 3～30 μ m left and right.

The formation of bond layer 6 can utilize according to the method for heat-releasable binder layer 4 to be carried out.As barrier film 7, can use the barrier film same with barrier film 5 on aforementioned hot removable adhesive layer 4.This adhesive sheet, by utilizing bond layer 6, can be fixed on seat surface and use.

[manufacture method of heat-peelable pressure-sensitive adhesive sheet]

Be provided with organic coating 2 at the one or both sides of base material 1, utilize any means to be coated with equably the composition before solidifying of the above-mentioned energy ray-curable elastic layer 3 of formation thereon.And, when the above-mentioned energy ray-curable elastic layer 3 forming in the one side of the base material obtaining contains the solvent beyond reactive solvents, for utilizing the dry state of having removed this solvent, make this energy ray-curable elastic layer 3 for utilizing the front state that solidifies of energy-ray.But, as long as possess sufficient mobility, also can make it partly solidified.

Be formed on separately the dry heat-releasable binder layer 4 forming of coating on the barrier film of preparation.The surface of this heat-releasable binder layer 4, the face of non-barrier film side is because contained heat-expandable microsphere is not embedded in this heat-releasable binder layer 4 completely, and therefore a part for this heat-expandable microsphere is outstanding and form protuberance from the teeth outwards.

Then, on the surface of this energy ray-curable elastic layer 3 before above-mentioned solidifying, be formed at stacked this heat-releasable binder layer 4 of the surperficial mode that is formed with protuberance of this heat-releasable binder layer 4 on above-mentioned barrier film with laminating, from this base material and this barrier film side, this energy ray-curable elastic layer 3 and this heat-releasable binder layer 4 are pressed each other, made this protuberance be embedded into the inside of this uncured energy ray-curable elastic layer 3.

Its result, can obtain this base material 1, organic coating 2, uncured this energy ray-curable elastic layer 3, this heat-releasable binder layer 4 and barrier film to stack gradually the sheet forming.

And then, for this this uncured energy ray-curable elastic layer 3, from base material 1 side and/or barrier film side irradiation energy ray, thereby this uncured energy ray-curable elastic layer 3 is solidified, can obtain thus heat-peelable pressure-sensitive adhesive sheet of the present invention.

The manufacture method of this heat-peelable pressure-sensitive adhesive sheet is the method that energy ray-curable elastic layer 3 and heat-releasable binder layer 4 are set in the one side of base material 1, when energy ray-curable elastic layer 3 and heat-releasable binder layer 4 are set on the two sides of base material 1, the method can be implemented every one side of base material successively, also can be implemented the two sides of base material simultaneously.

In addition, in the time that the another side of base material 1 arranges bond layer, can carry out the formation of this bond layer in any stage of front and back of the operation that energy ray-curable elastic layer 3 and heat-releasable binder layer 4 are set.

[using method of heat-peelable pressure-sensitive adhesive sheet]

Fig. 3 is the schematic flow sheet that an example of the manufacture method of the cut off machine that uses heat-peelable pressure-sensitive adhesive sheet of the present invention is shown.More specifically, Fig. 3 is the schema representing with the sectional view of following series of processes: crimping laminating adherend (being cut off body) 8 on the surface of the heat-releasable binder layer 4 of the energy ray-curable thermally strippable adhesive sheet (peeling off the state after barrier film 5) of Fig. 1, after according to circumstances utilizing the irradiation of energy-ray 9 that energy ray-curable elastic layer 3 is solidified, cut into specified dimension along cutting off line 10, make cut off machine, then utilize heat treated that the heat-expandable microsphere in heat-releasable binder layer 4 is expanded and foaming, peel off and reclaim cut off machine 8a.In addition, also can be after the irradiation that utilizes energy-ray 9 be solidified energy ray-curable elastic layer 3, crimping laminating adherend (being cut off body) 8 on heat-releasable binder layer 4 surfaces, cuts off along cutting off line 10.

In addition, be not limited to this cut-out, the purposes of heat-peelable pressure-sensitive adhesive sheet of the present invention has the manufacturing procedure such as grinding, punching conventionally.

In Fig. 3,1 represents base material, 3a represent energy-ray irradiate after fixing energy ray-curable elastic layer, 4a represent after energy-ray irradiates further to utilize heating to make the heat-releasable binder layer after heat-expandable microsphere expands.

The heat-releasable binder layer 4 of energy ray-curable thermally strippable adhesive sheet and the crimping of adherend 8 for example can be undertaken by the mode etc. of utilizing the suitable means of pressing such as rubber rollers, laminating roll, pressing unit to carry out crimping processing.Wherein, when crimping is processed, if the need arises, also can be according to the type of adhesive material, in the not dilatable temperature range of heat-expandable microsphere, heat, or be coated with water distribution, organic solvent and make adhesive material activation.

As energy-ray 9, can use visible ray, ultraviolet ray, electron beam etc.The irradiation of energy-ray 9 can utilize suitable method to carry out.But, make sometimes heat-expandable microsphere start to expand because of the irradiation heat of energy-ray 9, therefore it is desirable to, be limited in the irradiation of short period of time as far as possible, thereby or heat-peelable pressure-sensitive adhesive sheet is carried out to air cooling etc. remain on heat-expandable microsphere and can not start the temperature expanding.

The cut-out of adherend 8 can utilize the usual cut-out means such as cutting to carry out, for example, as cutting off shown in line 10 in Fig. 3, form and cut off line 10.

Heating condition can suitably be set according to the thermal capacity of the thermotolerance of the kind of the condition of surface of adherend 8 (or cut off machine 8a), thermotolerance, heat-expandable microsphere, adhesive sheet, adherend (being cut off body) etc., common condition optimization is temperature below 350C, treatment time below 30 minutes, is particularly preferably 80～200 ℃ of temperature, about 1 second～15 minutes treatment time.In addition, as type of heating, can list Hot-blast Heating mode, the hot plate way of contact, infrared heating mode etc., be not particularly limited.

In addition, the base material of heat-peelable pressure-sensitive adhesive sheet 1 uses while having the base material of retractility, extension process for example can by use by sheet class two-dimensional the usual expansion means used while expanding carry out.

Heat-peelable pressure-sensitive adhesive sheet of the present invention is owing to having the heat-releasable binder layer 4 that comprises adhesive material (tackiness agent), therefore bonding maintenance adherend 8 securely, and the vibration that such as adherend 8 can be when not carrying etc. is peeled off.In addition, heat-releasable binder layer 4 can form thinly, and, owing to by irradiation energy ray, energy ray-curable elastic layer 3 being solidified before cut-out operation, therefore compared with existing thermal expansivity adhesive sheet, can significantly reduce the fragmentation of following the movement of the rolling of the bond layer that caused by cutting knife, bond layer etc. and produce etc. when operation cutting off, and cut into the size of regulation.And then, heat-releasable binder layer 4 comprises heat-expandable microsphere, there is thermal expansivity, therefore by cutting off the heat treated after operation, heat-expandable microsphere promptly foams or expands, result is aforementioned hot removable adhesive layer 4 volume change as shown in the right figure of Fig. 3, form concavo-convex three-dimensional structure on surface, significantly reduces or lose with bond area and/or the bonding strength of the cut off machine 8a having cut off.

Therefore, by utilizing solidifying and utilizing obvious reduction or the forfeiture of the bonding strength of heat treated of energy ray-curable elastic layer 3 that energy-ray irradiates, operability and the workability of the peeling off of the cut-out operation of adherend 8, cut off machine 8a, recovery process are greatly improved, and production efficiency also can significantly improve.

Although energy ray-curable thermally strippable adhesive sheet of the present invention also can be for making permanently bonding purposes of adherend, be suitable within prescribed period of time bonding adherend and reaching the purposes that needs or wish to remove its adhering state after bonding object.As the object lesson of this purposes, can list in the assembling procedure of the immobilization material of semiconductor crystal wafer, ceramic layer lamination and various electrical means, electronic installation, display unit etc. for component feed, carrier band, temporary fixed material or immobilization material for temporary fixed etc., metal sheet, plastic plate, sheet glass etc. to prevent from polluting surface protecting material or the masking material etc. of damage as object.Especially in the manufacturing process of electronic unit, can be aptly for manufacturing process of semi-conductor chip, the cascade capacitor chip etc. of little or thin layer etc.

Embodiment

Then, according to embodiment, the present invention is described in detail.It should be noted that, the present invention is not subject to any restriction of these examples.

The making of the base material 1 with organic coating

As base material, prepare PET film.By Toray Industries, (thickness 50 μ are m) as this PET film for LUMIRROR S105 that Inc. manufactures, that one side corona treatment is crossed.Mode in the corona treatment face side of this base material take dry film thickness as 1～2 μ m is coated with organic coating with intaglio plate coating machine, dry, obtains the base material 1 with organic coating.In this organic coating, use light blue printing ink NB300 (Co., Ltd. refines large day).Wherein, in NB300, comprise polyurethane series vinyl-acetic ester-vinyl chloride copolymer as resin glue, utilize IR to confirm to be considered to the intensity peak of carbamate.

The making of the base material 2 with organic coating

As base material, prepare PET film.By Toray Industries, (thickness 50 μ are m) as this PET film for LUMIRROR S105 that Inc. manufactures, that one side corona treatment is crossed.Mode in the corona treatment face side of this base material take dry film thickness as 1～2 μ m is coated with organic coating with intaglio plate coating machine, dry, obtains the base material 2 with organic coating.In this organic coating, use not the printing ink NB300 containing nattier blue pigment (Co., Ltd. refines large day).Wherein, in NB300, comprise polyurethane series vinyl-acetic ester-vinyl chloride copolymer as resin glue, utilize IR to confirm to be considered to the intensity peak of carbamate.

The making of the base material 3 with organic coating

As base material, prepare PET film.By Toray Industries, (thickness 50 μ are m) as this PET film for LUMIRROR S105 that Inc. manufactures, that one side corona treatment is crossed.Mode in the corona treatment face side of this base material take dry film thickness as 1～2 μ m is coated with organic coating with intaglio plate coating machine, dry, obtains the base material 3 with organic coating.In this organic coating, be used as ADECABONTITER U500 (manufacture of ADEKA Co., Ltd.) 71 weight parts of polyurethane series silane coupling agent and the ethyl acetate solution as CORONATE HL (Nippon Polyurethane Industry Co., Ltd.'s manufacture) 28 weight parts of isocyanate resin.

The making of the base material 4 with organic coating

Drop into as 50.0 parts of the tert-butyl acrylates of acrylic monomer, 30.0 parts, vinylformic acid, 20.0 parts of butyl acrylates, as 1.0 parts of the Viscoat 295s of polyfunctional monomer, as 1-[4-(2-the hydroxyl-oxethyl)-phenyl of Photoepolymerizationinitiater initiater]-2-hydroxy-2-methyl-1-propane-1-ketone (trade(brand)name: IRGACURE2959, Ciba Specialty Chemicals Inc. manufactures) 0.1 part, as the polyoxygenated tetramethylene glycol (molecular weight 650 of polyvalent alcohol, Mitsubishi chemical Co., Ltd manufactures) 73.4 parts, as 0.05 part of the dibutyl tin laurate of urethane reaction catalyzer, stir while drip 26.6 parts of Xylene Diisocyanate, at 65 ℃, make its reaction 2 hours, obtain urethane polymer-acrylic monomer mixture.The consumption of polyisocyanates composition and polyhydroxy reactant is NCO/OH (equivalence ratio)=1.25.

Urethane polymer-acrylic monomer the mixture obtaining is applied to the pet film (trade(brand)name: S-10 of thickness 38 μ m take the thickness after solidifying as the mode of 3～4 μ m, Toray Industries, Inc. manufactures) on.(thickness 38 μ, m) by its coating, use high voltage mercury lamp radiation ultraviolet ray (illumination 163mW/cm to the PET pellicular front after this coating to the PET film that overlapping lift-off processing is crossed thereon ², light quantity 2100mJ/cm ²) it is solidified, obtain polyethylene terephthalate/acrylic acid or the like-carbamate lamination sheets.

The making of the base material 5 with organic coating

As base material, prepare PET film.By Toray Industries, (thickness 38 μ are m) as this PET film for LUMIRROR S105 that Inc. manufactures, that one side corona treatment is crossed.Mode in the corona treatment face side of this stiffness films layer take dry film thickness as 1～2 μ m is coated with organic coating with intaglio plate coating machine, dry, obtains the base material 5 with organic coating.In this organic coating, use blue printing ink CVL-PR (DICGRAPHICS CORPORATION manufacture).In CVL-PR, comprise hydroxyl vinyl-acetic ester-vinyl chloride copolymer as resin glue, the intensity peak to being considered to carbamate unconfirmed in IR.

The making of the base material 6 with organic coating

As base material, prepare PET film.By Toray Industries, (thickness 50 μ are m) as this PET film for LUMIRROR S105 that Inc. manufactures, that one side corona treatment is crossed.Mode in the corona treatment face side of this base material take dry film thickness as 1～2 μ m is coated with organic coating with intaglio plate coating machine, dry, obtains the base material 6 with organic coating.In this organic coating, use the saturated copolymer polyester resin of amorphism (LTD. manufactures for trade(brand)name: Vylon200, TOYOBO CO.).

The making of energy ray-curable binder layer

Will be at 2-EHA: morpholinyl acrylate: be added with the toluene solution copolymerization of polymerization starter benzoyl peroxide 0.2 weight part in vinylformic acid 2-hydroxyl ethyl ester=75:25:20 (mol ratio) mixture 100 weight parts, obtain acrylic polymers (weight-average molecular weight 700,000).In the aforementioned acrylic polymers obtaining, compounding is derived from the methacryloxyethyl isocyanic ester of 50 % by mole (methacrylic acid-2-isocyanato ethyl) of the hydroxyl of vinylformic acid 2-hydroxyl ethyl ester and is the addition reaction catalyst dibutyl tin laurate of 0.03 weight part with respect to the aforementioned acrylic polymers of 100 weight part, under air atmosphere, at 50 ℃, make its reaction 24 hours, manufacture side chain and there is methacrylate based acrylic polymers.The acrylic polymers obtaining with respect to 100 weight parts, add 3 functional acrylic photopolymerization monomers (Viscoat 295 (trade(brand)name: ARONIX M320, Toagosei Co., Ltd manufactures)) 15 weight parts, free base system Photoepolymerizationinitiater initiater (IRGACURE651,2,2-dimethoxy-1,2-diphenylethane-1-ketone, Nihon Ciba-Geigy K.K. manufactures) 1 weight part, isocyanate compound (trade(brand)name: CORONATE L, Nippon Polyurethane Industry Co., Ltd. manufactures) 1 weight part, obtain mixture.

Use mould to be coated with on machine is applied to the PET film MRF38 (manufacture of polyester Co., Ltd. of Mitsubishi) that lift-off processing crosses lift-off processing face take dry film thickness as the mode of 30 μ m in the mixture that obtains.Wherein, the PET film MRF38 that lift-off processing is crossed is as barrier film.

The making of heat-releasable binder layer

With respect to 00 part of the copolymer 1 being formed by ethyl propenoate-2-EHA-vinylformic acid 2-hydroxyl ethyl ester (80 parts-20 parts-5 parts), compounding " CORONATE L " (linking agent, Nippon Polyurethane Industry Co., Ltd. manufactures) 1 part, heat-expandable microsphere " Matsumoto Microsphere the F-50D " (heat-expandable microsphere of 120 ℃ of foaming and intumescing types, this grease of pine is manufactured) 30 parts, modulation mixed solution.This mixed solution is applied on the lift-off processing face of the PET film MRF38 (manufacture of polyester Co., Ltd. of Mitsubishi) that lift-off processing crosses, is dried, obtain the heat-releasable binder layer of 10 μ m.

Embodiment 1

At the organic coating side of the base material 1 with the organic coating above-mentioned energy ray-curable binder layer of fitting, the above-mentioned heat-releasable binder layer of then fitting, thus make heat-peelable pressure-sensitive adhesive sheet.

Embodiment 2

At the organic coating side of the base material 2 with the organic coating above-mentioned energy ray-curable binder layer of fitting, the above-mentioned heat-releasable binder layer of then fitting, thus make heat-peelable pressure-sensitive adhesive sheet.

Embodiment 3

At the organic coating side of the base material 3 with the organic coating above-mentioned energy ray-curable binder layer of fitting, the above-mentioned heat-releasable binder layer of then fitting, thus make heat-peelable pressure-sensitive adhesive sheet.

Embodiment 4

At the organic coating side of the base material 4 with the organic coating above-mentioned energy ray-curable binder layer of fitting, the above-mentioned heat-releasable binder layer of then fitting, thus make heat-peelable pressure-sensitive adhesive sheet.

Comparative example 1

At Toray Industries, (thickness 50 μ are the above-mentioned energy ray-curable binder layer of upper laminating m), the above-mentioned heat-releasable binder layer of then fitting, thereby making heat-peelable pressure-sensitive adhesive sheet for the PET film LUMIRROR S10 that Inc. manufactures.

Comparative example 2

At Toray Industries, Inc. (thickness 50 μ are the above-mentioned energy ray-curable binder layer of upper laminating m) for the LUMIRROR S105 manufacturing, one side corona treatment is crossed, then the above-mentioned heat-releasable binder layer of fitting, thus heat-peelable pressure-sensitive adhesive sheet made.

Reference example 1

At the organic coating side of the base material 5 with the organic coating above-mentioned energy ray-curable binder layer of fitting, the above-mentioned heat-releasable binder layer of then fitting, thus make heat-peelable pressure-sensitive adhesive sheet.

Reference example 2

At the organic coating side of the base material 6 with the organic coating above-mentioned energy ray-curable binder layer of fitting, the above-mentioned heat-releasable binder layer of then fitting, thus make heat-peelable pressure-sensitive adhesive sheet.

Energy-ray irradiates

The UV irradiating machine NEL UM810 (high voltage mercury lamp light source, the 20mW/cm that use Dong Jing machine Co., Ltd. to manufacture to the heat-peelable pressure-sensitive adhesive sheet obtaining ²) carry out 300mJ/cm ²uviolizing, make energy ray-curable elastic layer solidify.

On the tackiness agent face of above-mentioned heat-peelable pressure-sensitive adhesive sheet, attach the ceramic plate before the roasting of 120mm × 100mm × thickness 0.5mm, entirely cut into the chip of 0.4mm × 0.2mm.Then, on hot plate, carry out the heat treated of 120 ℃ × 3 minutes, cooling after, chip is reclaimed in the vibration of being overturn.

Add thermally strippable evaluation

When chip is reclaimed in the vibration of being overturn after heat treated, the chip-count of not peeling off in counting 100 chips.

Glue exfoliative is evaluated

Ceramic plate is cut entirely, use observation by light microscope to carry out the tackiness agent face that adds thermally strippable adhesive sheet after heat treated, the quantity that the glue in counting 100 chips strips off.The degree that its glue strips off is also illustrated in the degree of the cull on chip surface.

Cut off precision

In order to obtain cut-out precision, adopt following method.

The cross section of the chip after cutting off with observation by light microscope, obtains the angle of cross section with respect to ceramic plate surface, sets it as cut-out precision.This angle more approaches 90 ° and means that cut-out precision is more excellent.

By the various embodiments described above and comparative example and the results are shown in following table 1.

[table 1]

While using the heat-peelable pressure-sensitive adhesive sheet of embodiment 1～6 entirely to cut ceramic plate, when the chip that obtains in recovery, there is no unstripped chip, add thermally strippable good.

In addition, there is not glue and strip off in the adhesive face that adds thermally strippable adhesive sheet after full cutting.

From these results, according to the present invention, the skew of the tackiness agent can suppress to cut off operation time, roll, fragmentation, and after cut-out can by cut off with high precision processing after cut off machine easily peel off recovery.Now known, can obviously improve operability and the workability of the peeling off of cut off machine, recovery process, significantly improve thus precision or improve the productivity of the cut off machine of semi-conductor chip, the cascade capacitor chip etc. of small-sized or thin layer.

On the other hand, known, use while not being provided with the heat-peelable pressure-sensitive adhesive sheet of comparative example 1 and 2 of organic coating, adding thermally strippable and glue strips off all bad, according to comparative example 3, add the result that thermally strippable, glue strip off good, but it is low to cut off precision, the processibility when ceramic plate of having fixed is cut entirely worsens.

And then, the heat-peelable pressure-sensitive adhesive sheet of reference example 1 and 2 be as organic coating adopt is formed by the material beyond carbamate based polymer layer example, similarly add thermally strippable with comparative example 1 and 2 and glue strips off all bad.

In addition, according to reference example 3, add thermally strippable good, do not have glue to strip off, cut off precision also good, but thin thickness to the 0.8 μ m of thermally strippable binder layer, therefore keeps the binding property deficiency of adherend, produces the new problem that in processing, adherend is peeled off.

From the result of these embodiment and comparative example, reference example, in heat-peelable pressure-sensitive adhesive sheet of the present invention, adopt the organic coating being formed by carbamate based polymer, thereby be not the significant effect of performance compared with such situation.

Claims

1. a heat-peelable pressure-sensitive adhesive sheet, it is characterized in that, its at least one side at base material clips the heat-releasable binder layer that the setting of energy ray-curable elastic layer contains heat-expandable microsphere and forms, and described heat-peelable pressure-sensitive adhesive sheet disposes organic coating between described base material and energy ray-curable elastic layer.

2. heat-peelable pressure-sensitive adhesive sheet according to claim 1, wherein, described organic coating is formed by carbamate based polymer.

3. heat-peelable pressure-sensitive adhesive sheet according to claim 1 and 2, is characterized in that, the thickness of heat-releasable binder layer is below 50 μ m.