JP2013173876A - Adhesive tape - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an adhesive tape that can obtain stable adhesion characteristics and peeling characteristics and can keep contamination of an adherend to the minimum even in various environments.SOLUTION: An adhesive tape is obtained by forming a pressure-sensitive adhesive layer on one side of a thermoplastic resin film in which a methylenebis(fatty acid amide) and a fatty acid are contained in at least one of the thermoplastic resin film and the pressure-sensitive adhesive layer and a fatty acid monoamide as a byproduct during formation of the methylenebis(fatty acid amide) is not substantially contained.

Description

  The present invention relates to an adhesive tape.

Conventionally, a PVC film or the like has been used as a base layer of an adhesive tape that can be re-peeled in a semiconductor manufacturing process or the like. The pressure-sensitive adhesive tape is configured by applying a pressure-sensitive adhesive layer to one surface of a base material layer made of such a PVC film, and a fatty acid amide is added to the base material or the pressure-sensitive adhesive (Patent Document 1). Rewindability and adhesion to the adherend are controlled by appropriately bleeding the fatty acid amide on the surface.
Further, it has been proposed to obtain good peelability and contamination resistance by adding a urea compound and hydrotalcite to a vinyl chloride resin (Patent Document 2).

  However, under the present circumstances, the adhesive property is not stable, and the adherend to the adherend such as a semiconductor wafer when the adhesive tape is peeled off is large. In particular, when the adhesive tape is peeled off from the adherend due to the storage state of the adhesive tape, the storage state after bonding to the adherend, etc., it becomes difficult to peel off or contaminants such as an adhesive remain on the adherend. Etc. may occur.

JP 57-139163 A JP 07-276516 A

  The present invention has been made in view of the above problems, and can provide a stable adhesive property and peeling property even under various environments, and can minimize contamination on an adherend. The purpose is to provide.

  As a result of diligent research on the adhesive properties and release properties of the current re-peelable pressure-sensitive adhesive tape, the present inventors have found that methylene bis-fatty acid amide contained as an additive in the base material layer or pressure-sensitive adhesive layer of the pressure-sensitive adhesive tape The present inventors have found that there are many impurities derived from raw materials and by-products during synthesis, and that the amount of impurities in the commercial product has a large variation for each production lot. Therefore, by removing impurities of methylene bis fatty acid amide and adding it to the base material layer or pressure sensitive adhesive layer of the pressure sensitive adhesive tape, it is possible to unexpectedly stabilize the adhesive properties and to adhere to the adherend when peeled. It has been found that contamination can be significantly reduced. In addition, as a result of detailed examination of each component that becomes an impurity for methylene bis fatty acid amide, the fatty acid generated during the formation of methylene bis fatty acid amide effectively increases the time-dependent increase in adhesive strength after bonding of the adhesive tape to the adherend. It was newly found that it can be suppressed. As a result, by intentionally containing a predetermined amount of fatty acid in the methylene bis-fatty acid amide from which impurities have been removed, in various environments, the balance of storage of adhesive tape and pasting to adherend has been balanced and stabilized. The pressure-sensitive adhesive tape of the present invention capable of obtaining adhesive properties and peeling properties has been completed.

That is, the adhesive tape of the present invention is
A pressure-sensitive adhesive tape in which a pressure-sensitive adhesive layer is formed on one side of a thermoplastic resin film, and at least one of the thermoplastic resin film and the pressure-sensitive adhesive layer contains methylene bis fatty acid amide and a fatty acid, It is characterized by substantially not containing fatty acid monoamide, which is a by-product during the production of methylene bis fatty acid amide.
Such an adhesive tape preferably includes one or more of the following.
The methylene bis fatty acid amide is obtained by removing the fatty acid monoamide as the by-product by solvent extraction.
Methylene bis fatty acid amide is a compound represented by the formula (I).
_{^{R 1 -Am-CH 2 -Am-}} R 2 (I)
(In the formula, R ¹ and R ² each independently represents a saturated or unsaturated hydrocarbon group having 6 to 23 carbon atoms, and Am represents a secondary amide group.)
The fatty acid is contained in the range of 0.1 to 30 parts by weight with respect to 100 parts by weight of the methylene bis fatty acid amide.
Methylene bis-fatty acid amide and fatty acid are each contained in the range of 0.1 to 5.0 parts by weight with respect to 100 parts by weight of the thermoplastic resin.
The thermoplastic resin film is a film made of soft polyvinyl chloride containing a plasticizer.
The pressure-sensitive adhesive layer contains an acrylic polymer as a base polymer.
A release liner is disposed on the pressure-sensitive adhesive layer side of the adhesive tape.

  According to the pressure-sensitive adhesive tape of the present invention, stable adhesion characteristics and peeling characteristics can be obtained under various environments, and contamination on the adherend can be minimized.

〔Adhesive tape〕
The pressure-sensitive adhesive tape of the present invention is mainly formed by a thermoplastic resin film as a base material layer and a pressure-sensitive pressure-sensitive adhesive layer laminated on one surface of the thermoplastic resin film. Either one of the thermoplastic resin film and the pressure-sensitive adhesive layer contains methylene bis fatty acid amide and a fatty acid. These layers are substantially free of fatty acid monoamide. The methylene bis fatty acid amide and the fatty acid may be contained only in the thermoplastic resin film or the pressure sensitive adhesive layer, either one is contained in the pressure sensitive adhesive layer, and the other is contained in the thermoplastic resin film. One of them may be contained in the pressure-sensitive adhesive layer, the other may be contained in both the pressure-sensitive adhesive layer and the thermoplastic resin film, or one of them may be contained in the thermoplastic resin film and the other is sensitive. It may be contained in both the pressure-sensitive adhesive layer and the thermoplastic resin film, or may be contained in both the thermoplastic resin film and the pressure-sensitive adhesive layer.
As will be described later, when the thermoplastic resin film and / or the pressure-sensitive adhesive layer has a laminated structure, it may be contained in one of them, but at least the thermoplastic resin film and the pressure-sensitive adhesive layer Are preferably contained in layers in contact with each other.
The pressure-sensitive adhesive tape of the present invention is suitably provided with a release liner in contact with the pressure-sensitive pressure-sensitive adhesive layer as necessary.

[Methylene bis fatty acid amide]
The methylene bis fatty acid amide in the present invention can be represented by, for example, the formula (I).
_{^{R 1 -Am-CH 2 -Am-}} R 2 (I)
(In the formula, R ¹ and R ² each independently represents a saturated or unsaturated hydrocarbon group having 6 to 23 carbon atoms, and Am represents a secondary amide group.)

（式中、Ｒ¹及びＲ²は、それぞれ独立して、炭素数６〜２３の飽和又は不飽和炭化水素基を表す。） Examples of the compound represented by the formula (I) include compounds represented by the formula (II) or the formula (III).

(In the formula, R ¹ and R ² each independently represents a saturated or unsaturated hydrocarbon group having 6 to 23 carbon atoms.)

This methylene bis fatty acid amide may be contained alone or in combination of two or more. More specifically, the compounds represented by the formula (II) and the formula (III) may each be one kind, a mixture of two or more kinds, or the formula (II) It may be a mixture of the compound represented by the formula (III). In formulas (I) to (III), R ¹ and R ² may be different from each other, but are preferably the same.
Of these, the compound represented by the formula (II) is preferable.
Furthermore, as the compound represented by the formula (II), a compound represented by the formula (IV) is more preferable.
_{CH 3 - (CH 2) n} -CO-NH-CH 2 -NH-CO- (CH 2) m -CH 3 (IV)
(In the formula, n and m each independently represent an integer of 5 to 22.)

Here, the saturated or unsaturated hydrocarbon group includes any of linear, branched, cyclic, and combinations thereof.
Saturated hydrocarbon groups include methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, t-butyl, pentyl, hexyl, heptyl, octyl, decyl, dodecyl A chain alkyl group such as a group, tetradecyl group, hexadecyl group, octadecyl group;
Branched alkyl groups such as ethylhexyl, ethyloctyl, propylhexyl;
Examples thereof include cyclic alkyl groups such as a cyclopentyl group, a cyclohexyl group, and a cycloheptyl group.
Examples of the unsaturated hydrocarbon group include an alkenyl group such as a propenyl group, an isopropenyl group, a 2-propenyl group, a 9-octadecynyl group, a cyclopentenyl group, and a cyclohexenyl group, and a cycloalkenyl group.

In the formulas (I) to (III), the carbon number is preferably 8 to 20, and more preferably 10 to 18. Saturated hydrocarbons are preferred.
In the formula (IV), n and m preferably have 7 to 19 carbon atoms, more preferably 9 to 17 carbon atoms, and still more preferably 11 to 17 or 13 to 15 carbon atoms.
The secondary amide group in formula (I) means a divalent amide group, and the carbon atom in the amide group may be bonded to either R ¹ or R ² and a methylene group.

Specific compounds of formula (II) include
N, N′-methylenebiscapric amide,
N, N′-methylenebislauric acid amide,
N, N′-methylenebismyristic acid amide,
N, N′-methylenebispalmitic acid amide,
N, N′-methylenebisoleic acid amide,
N, N′-methylenebisstearic acid amide,
N, N'-methylenebisbehenamide,
N, N′-methylenebiserucic acid amide and the like can be mentioned.

Specific compounds of formula (III) include
N, N′-dicaprylmalonic acid amide,
N, N'-dilarylmalonamide,
N, N′-dimyristyl malonamide,
N, N′-dipalmitylmalonamide,
N, N′-dioleoylmalonic acid amide,
N, N′-distearylmalonic acid amide,
N, N′-dibehenylmalonic acid amide,
N, N′-diercarylmalonic acid amide and the like can be mentioned.

  Among them, N, N′-methylenebisstearic acid amide, N, N′-methylenebispalmitic acid amide and combinations thereof are preferable, and N, N′-methylenebisstearic acid amide and N, N′-methylenebisamide are preferable. More preferred is a mixture of palmitic amides. In the case of a mixture, the content ratios of N, N′-methylenebisstearic acid amide and N, N′-methylenebispalmitic acid amide are methylene bisstearic acid amide: methylene bispalmitic acid amide = 1 to 10: The content is preferably about 10 to 1, more preferably about 5 to 8: 2 to 5.

Normally, methylene bis fatty acid amide is produced by the reaction of fatty acid amide and formaldehyde as shown below. Moreover, fatty acid amide is industrially produced | generated by reaction of a fatty acid and ammonia.
2R—CO—NH ₂ + HCHO → R—CO—NH—CH ₂ —NH—CO—R
R—CO—NH ₂ + HCHO → R—CO—NH—CH ₂ OH
(Wherein R represents a saturated or unsaturated hydrocarbon group)
Further, a methylene bis fatty acid amide such as R—NH—CO—CH ₂ —CO—NH—R can be synthesized by utilizing a known synthesis method and / or conditions.

However, in the above-described production method, not only bis-fatty acid amide but also mono-fatty acid amide (also sometimes referred to as mono-fatty acid amide) is produced as a by-product (including the residue of what was used as a raw material). As the purity of the material fluctuates, it seems that its accuracy is not strictly controlled in industrial processes. Actually, when analyzing the purity of the commercially available methylene bis fatty acid amide, it was confirmed that it contains a large amount of impurity components and has a large variation among production lots as follows.
Methylene bis-stearic acid amide / methylene bis-palmitic acid amide together about 70%,
Stearamide 1-4%,
Palmitic acid amide 0.5-1.5%,
1-5% stearic acid,
Palmitic acid 0.5-1.5% and trisamide about 20%.

  Thus, in theory, methylene bis fatty acid amide obtained by the reaction of fatty acid amide and formaldehyde and having a very high purity by the purification can exist, but in reality, as an industrial product, impurities are substantially reduced. There is no methylene bis fatty acid amide not present.

In the pressure-sensitive adhesive tape of the present invention, the methylene bis fatty acid amide itself is contained with high purity, so that the intended properties can be exhibited and unintended effects can be suppressed as much as possible.
Therefore, the methylene bis fatty acid amide obtained by the reaction of the fatty acid amide and formaldehyde is preferably purified by being subjected to extraction with a predetermined solvent (including washing).
As the solvent here, it is suitable to use a solvent that dissolves the mono-fatty acid amide used as a raw material but does not dissolve the methylene bis-fatty acid amide. In order to further increase the purity of the methylene bis fatty acid amide obtained by the reaction between the fatty acid amide and formaldehyde, it is preferable to use a solvent that also dissolves the fatty acid used as the raw material of the fatty acid amide. Here, dissolving means that the amount of solvent necessary for dissolving 1 g of solute is 10 g or less, and not dissolving means that the amount of solvent necessary for dissolving 1 g of solute is 100 g or more. Means.
Specifically as this solvent, chloroform, ethanol, methanol, these heating solvents, etc. are mentioned. Of these, chloroform, heated ethanol, heated methanol and the like are preferable.

  Any known method can be used for extraction. Examples thereof include a method in which methylene bis fatty acid amide obtained by the reaction of fatty acid monoamide and formaldehyde is immersed in a solvent for washing, and a method in which the obtained methylene bis fatty acid amide is subjected to Soxhlet extraction using a solvent. The conditions at this time are not particularly limited. For example, a solvent having a volume of about 30 to 100 times or a weight of methylenebisfatty acid amide is added, and immersion, immersion, washing or extraction is performed for about 30 minutes to several hours. Do. Depending on the type of solvent used, the solvent may be heated to room temperature to about 100 ° C. Further, if necessary, such an operation may be repeated a plurality of times by changing the solvent type or using the same type of solvent. The obtained insoluble matter is separated by a known means such as filtration.

It is preferable to dry insoluble matter after extraction. Drying can utilize any method commonly performed in the art. The drying conditions and temperature are not particularly limited and are preferably adjusted as appropriate.
Specifically, in the case of chloroform extraction, for example, 40 ml of chloroform is added to about 1 g of commercially available methylene bis-fatty acid amide, soaked for 1 hour using a soaking machine, and then insoluble and soluble components by suction filtration. To separate. Optionally, the purified methylenebis fatty acid amide composition can be obtained by performing the same operation about the obtained chloroform-insoluble matter about twice more.
In the case of ethanol extraction, for example, 40 ml of ethanol is added to about 1 g of commercially available methylene bis fatty acid amide, and the mixture is extracted by heating at 80 ° C. (hot plate temperature) for 1 hour. Then, it isolate | separates into a supernatant liquid (soluble matter) and a precipitate (insoluble matter), and performs the same operation about the obtained ethanol insoluble matter twice further, and obtains the refined methylenebis fatty acid amide composition. be able to.

Thus, by solvent extraction of methylene bis fatty acid amide, by-product / residual fatty acid monoamide (preferably further fatty acid) can be removed during the production of methylene bis fatty acid amide, and a highly pure methylene bis fatty acid amide can be obtained. Can do.
The methylene bis fatty acid amide used in the present invention is substantially free from fatty acid monoamides. That is, even if a normal analytical instrument (liquid chromatograph, high performance liquid chromatograph, etc.) contains a fatty acid monoamide (preferably also a fatty acid) as a single species, it is less than 0.25% by weight, 0.0. Less than 2% by weight, less than 0.1% by weight, 0.05% by weight, even if measured below the detection limit or contained in multiple species, the total amount is less than 1% by weight, 0.8% by weight %, Less than 0.5 wt%, less than 0.4 wt%, less than 0.3 wt%, 0.05 wt%, preferably below the detection limit.
The fatty acid monoamide that is not substantially contained (removed) is not only a by-product that is produced during the production of methylene bis-fatty acid amide, but is also produced at least as a by-product after the production. It means that the fatty acid monoamide of the same kind, preferably, a different kind of fatty acid monoamide is not contained.

That is, the methylene bis-fatty acid amide used in the present invention is a fatty acid monoamide derived from the raw material / production method or the like / different fatty acid monoamides such as lauric acid monoamide, stearic acid monoamide, oleic acid monoamide, erucic acid monoamide, capric acid. Monoamide, palmitic acid monoamide, myristic acid monoamide, behenic acid monoamide;
N-oleyl stearic acid monoamide, N-oleyl oleic acid monoamide, N-stearyl stearic acid monoamide, N-stearyl oleic acid monoamide, N-oleyl palmitic acid monoamide, N-stearyl erucic acid monoamide, etc., especially stearic acid monoamide, palmitic It contains substantially no acid monoamide or the like.

  The methylene bis fatty acid amide used in the present invention is a fatty acid derived from the raw material or the like or a fatty acid of the same / different kind, such as capric acid, stearic acid, oleic acid, erucic acid, lauric acid, palmitic acid, myristic acid, It is preferable that behenic acid and the like, especially stearic acid, oleic acid, palmitic acid and the like are not contained, and it is more preferable that stearic acid and palmitic acid and the like are not contained. Alternatively, even if the methylene bis fatty acid amide contains a fatty acid derived from a raw material or the like, it is suitable to measure the content by analysis or the like. This is because, as will be described later, either one of the thermoplastic resin film and the pressure-sensitive adhesive layer contains a fatty acid with a specific content. The fatty acid in this case may be the same type of fatty acid as that constituting the methylene bis fatty acid amide, may be a different fatty acid, or a mixture of two or more of these. That is, the fatty acid is contained in at least one of the thermoplastic resin film and the pressure-sensitive pressure-sensitive adhesive layer, but the total amount is a combination of each component when producing the thermoplastic resin film or the pressure-sensitive pressure-sensitive adhesive layer. It is suitable to be controlled at times.

  As described above, the methylene bis fatty acid amide used in the present invention is substantially free of fatty acid amide (preferably substantially free of fatty acid). A minor component such as an amide tris may be contained. It is preferable that such a tris body is not substantially contained.

In the pressure-sensitive adhesive tape of the present invention, the amount of methylenebisfatty acid amide and fatty acid added to the thermoplastic resin film is, for example, about 0.1 to 5.0 parts by weight with respect to 100 parts by weight of the thermoplastic resin in the thermoplastic resin film, respectively. It is preferable that it is the range of this, and it is more preferable that it is about 0.1-3.0 weight part.
The amount of methylene bis fatty acid amide and fatty acid added in the pressure-sensitive adhesive layer is, for example, preferably in the range of about 0.1 to 5.0 parts by weight with respect to 100 parts by weight of the base polymer described later, More preferably, it is about 0.1 to 3.0 parts by weight.
When methylene bis-fatty acid amide and fatty acid are added to both the thermoplastic resin film and / or the pressure-sensitive adhesive layer, the total amount added is 0.1 to 5.0 with respect to 100 parts by weight of the thermoplastic resin. It is preferable to adjust appropriately in the range of about parts by weight, and more preferably about 0.1 to 3.0 parts by weight.

  In the adhesive tape of the present invention, the fatty acid is suitably contained in a range of about 0.1 to 30 parts by weight with respect to 100 parts by weight of methylenebisfatty acid amide, about 0.1 to 20 parts by weight, It is preferably contained in the range of about 0.1 to 10 parts by weight and about 0.1 to 5 parts by weight. In addition, even if the methylene bis fatty acid amide and the fatty acid are contained in different layers, the content described above means the total amount in each layer constituting the adhesive tape.

(Thermoplastic resin film)
The thermoplastic resin film of the present invention is not particularly limited, and for example, low density polyethylene, linear polyethylene, medium density polyethylene, high density polyethylene, ultra low density polyethylene, random copolymer polypropylene, block copolymer polypropylene, homopolypropylene. , Polyolefins such as polybutene and polymethylpentene; ethylene-vinyl acetate copolymer, ionomer resin, ethylene- (meth) acrylic acid copolymer, ethylene- (meth) acrylic acid ester (random, alternating) copolymer, ethylene -Polyolefin resins such as butene copolymer and ethylene-hexene copolymer; Polyester resins such as polyurethane, polyethylene terephthalate, and polyethylene naphthalate; (Meth) acrylic polymers, polystyrene, polycarbonate Polyimide, polyamide, polyamideimide, polyetherimide, polysulfone, polyether sulfone, polyvinyl chloride, polyvinylidene chloride, fluorine resins, films made of cellulose resins and thermoplastic resins such as a cross-linked product thereof. These thermoplastic resins may be used by blending several kinds as required. Of these, a vinyl chloride resin film is preferable.

The vinyl chloride resin includes polyvinyl chloride, a vinyl chloride copolymer, a graft copolymer onto polyvinyl chloride, and a mixture with other resins.
Examples of the comonomer in the vinyl chloride copolymer include vinyl esters such as vinyl acetate, vinyl ethers such as ethylene vinyl ether, α-olefins such as ethylene, propylene, and 1-butene, methyl acrylate, (Meth) acrylic acid esters such as ethyl acrylate, methyl methacrylate and butyl methacrylate, vinylidene chloride and the like.
In particular, when a vinyl chloride resin is used, a soft vinyl chloride resin to which a plasticizer described later is added is preferable.

The thermoplastic resin film preferably contains a plasticizer so that the pressure-sensitive adhesive tape obtained from the thermoplastic resin film exhibits appropriate flexibility. Further, if necessary, a stabilizer, a filler lubricant, a colorant, and an ultraviolet absorber. An additive such as an agent and an antioxidant may be included.
The plasticizer is not particularly limited, and for example, phthalate ester-based, trimellitic acid ester-based (Dainippon Ink Co., Ltd. W-700, trimellitic acid trioctyl, etc.), adipic acid ester-based ((Co., Ltd.) ) JPLUS D620, dioctyl adipate, diisononyl adipate, etc.), phosphate esters (such as tricresyl phosphate), adipic acid esters, citrate esters (acetylbutyl citrate, etc.), sebacic acid esters, aceleic acid esters , Maleic acid ester, benzoic acid ester, polyether-based polyester, epoxy-based polyester (epoxidized soybean oil, epoxidized linseed oil, etc.), polyester (low-molecular polyester composed of carboxylic acid and glycol, etc.) and the like. Among these, it is preferable to use an ester plasticizer. You may use these individually or in combination of 2 or more types.
The plasticizer is suitably used at a ratio of, for example, 10 to 60 parts by weight with respect to 100 parts by weight of the thermoplastic resin, and preferably 10 to 30 parts by weight.

The stabilizer is not particularly limited, and examples thereof include composite stabilizers such as barium-zinc, tin, calcium-zinc, and cadmium-barium.
Examples of the filler include inorganic fillers such as calcium carbonate, silica and mica, and metal fillers such as iron and lead.
Examples of the colorant include pigments and dyes.
Any other additive known in the art can be used.

The thermoplastic resin film may be a single-layer film, or may be a laminate of films (multilayer film) that is different in material or composition and takes advantage of each resin.
The thickness of the thermoplastic resin film can be adjusted depending on the physical properties of the adhesive tape to be obtained, for example, 30 to 1000 μm, preferably 40 to 800 μm, more preferably 50 to 500 μm, and particularly preferably 60 to 200 μm. Can be mentioned.
In order to improve the adhesiveness to the pressure sensitive adhesive on the front and back surfaces of the thermoplastic resin film, in particular, the top surface, that is, the surface on which the pressure sensitive adhesive layer is provided, a conventional surface treatment such as corona treatment, chromic acid treatment, Oxidation by a chemical or physical method such as ozone exposure, flame exposure, high-voltage impact exposure, or ionizing radiation treatment may be performed.

(Pressure-sensitive adhesive layer)
The pressure-sensitive adhesive (hereinafter sometimes simply referred to as “adhesive”) layer is formed of a pressure-sensitive adhesive. The pressure sensitive adhesive is not particularly limited. For example, depending on the type of base polymer constituting the adhesive, a rubber adhesive, an acrylic adhesive, a polyamide adhesive, a silicone adhesive, and a polyester adhesive. Although an adhesive, a urethane type adhesive, etc. are mentioned, It can select suitably from these well-known adhesives. Among these, acrylic pressure-sensitive adhesives are excellent in various properties such as heat resistance and weather resistance, and can exhibit desired properties by selecting the types of monomer components constituting the acrylic polymer. Can be preferably used.

The acrylic pressure-sensitive adhesive is usually formed of a base polymer composed mainly of an acrylic polymer such as (meth) acrylic acid alkyl ester.
Examples of the (meth) acrylic acid alkyl ester include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, (meth) Isobutyl acrylate, sec-butyl (meth) acrylate, t-butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, 2-Methylhexyl acrylate, isooctyl (meth) acrylate, nonyl (meth) acrylate, isononyl (meth) acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate, undecyl (meth) acrylate , Dodecyl (meth) acrylate, tridecyl (meth) acrylate, Alkyl esters of (meth) acrylic acid C1-C20 such as tetradecyl (meth) acrylate, pentadecyl (meth) acrylate, octadecyl (meth) acrylate, nonadecyl (meth) acrylate, eicosyl (meth) acrylate (preferably ( (Meth) acrylic acid C1-C12 alkyl ester, more preferably (meth) acrylic acid C1-C8 alkyl ester). One or more (meth) acrylic acid alkyl esters can be selected and used.

Acrylic polymers contain units corresponding to other monomer components copolymerizable with (meth) acrylic acid alkyl esters as necessary for the purpose of modifying cohesive strength, heat resistance, crosslinkability and the like. You may go out.
As such a monomer component, for example,
Carboxyl group-containing monomers such as acrylic acid, methacrylic acid, carboxyethyl acrylate, carboxypentyl acrylate, itaconic acid, maleic acid, fumaric acid, crotonic acid;
Hydroxybutyl (meth) acrylate, hydroxyhexyl (meth) acrylate, hydroxyoctyl (meth) acrylate, hydroxydecyl (meth) acrylate, hydroxylauryl (meth) acrylate, (4-hydroxymethylcyclohexyl) methyl methacrylate, etc. A hydroxyl group-containing monomer of
Sulphonic acid groups such as styrene sulfonic acid, allyl sulfonic acid, 2- (meth) acrylamide-2-methylpropane sulfonic acid, (meth) acrylamide propane sulfonic acid, sulfopropyl (meth) acrylate, (meth) acryloyloxynaphthalene sulfonic acid Containing monomers;

Phosphoric acid group-containing monomers such as 2-hydroxyethyl acroyl phosphate, (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N-butyl (meth) acrylamide, N-methylol (meth) acrylamide, N-methylolpropane (N-substituted) amide monomers such as (meth) acrylamide;
(Meth) acrylic acid aminoalkyl monomers such as (meth) acrylic acid aminoethyl, (meth) acrylic acid N, N-dimethylaminoethyl, (meth) acrylic acid t-butylaminoethyl;
(Meth) acrylic acid alkoxyalkyl monomers;
Maleimide monomers such as N-cyclohexylmaleimide, N-isopropylmaleimide, N-laurylmaleimide, N-phenylmaleimide;
Itaconimide monomers such as N-methylitaconimide, N-ethylitaconimide, N-butylitaconimide, N-octylitaconimide, N-2-ethylhexylitaconimide, N-cyclohexylitaconimide, N-laurylitaconimide;

Succinimide monomers such as N- (meth) acryloyloxymethylene succinimide, N- (meth) acryloyl-6-oxyhexamethylene succinimide, N- (meth) acryloyl-8-oxyoctamethylene succinimide;
Vinyl acetate, vinyl propionate, N-vinyl pyrrolidone, methyl vinyl pyrrolidone, vinyl pyridine, vinyl piperidone, vinyl pyrimidine, vinyl piperazine, vinyl pyrazine, vinyl pyrrole, vinyl imidazole, vinyl oxazole, vinyl morpholine, N-vinyl carboxylic acid amides, Vinyl monomers such as styrene, α-methylstyrene, N-vinylcaprolactam;

Cyanoacrylate monomers such as acrylonitrile and methacrylonitrile;
Epoxy group-containing acrylic monomers such as (meth) glycidyl acrylate;
Glycol-based acrylic ester monomers such as (meth) acrylic acid polypropylene glycol, (meth) acrylic acid methoxyethyl glycol, (meth) acrylic acid methoxypolypropylene glycol;
Acrylic acid ester monomers having a heterocyclic ring such as tetrahydrofurfuryl (meth) acrylate, fluorine (meth) acrylate, silicone (meth) acrylate, halogen atoms, silicon atoms, etc .;

Hexanediol di (meth) acrylate, (poly) ethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, pentaerythritol di (meth) acrylate, trimethylolpropane tri (meth) ) Polyfunctional monomers such as acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, epoxy acrylate, polyester acrylate, urethane acrylate, divinylbenzene, butyl di (meth) acrylate, hexyl di (meth) acrylate;
Olefin monomers such as isoprene, dibutadiene, isobutylene;
And vinyl ether monomers such as vinyl ether. These monomer components can be used alone or in combination of two or more.

The acrylic copolymer can be produced by subjecting the above (meth) acrylic acid alkyl ester and, if necessary, other monomers to polymerization by a known appropriate method.
The molecular weight of the acrylic copolymer is not particularly limited, and for example, those having a weight average molecular weight of 100,000 to 2,000,000, preferably 150,000 to 1,000,000, more preferably 300,000 to 1,000,000 can be used. The weight average molecular weight can be a value measured, for example, by gel permeation chromatography (GPC) using polystyrene as a molecular weight standard substance.

  The pressure sensitive adhesive can be made into an energy ray curable pressure sensitive adhesive by adding an energy ray polymerizable compound or introducing an energy ray polymerizable double bond into the base polymer. The pressure-sensitive adhesive layer using the energy ray-curable pressure-sensitive adhesive exhibits a sufficient adhesive force with the adherend before irradiation with the energy beam, but the adhesive strength significantly decreases after the irradiation with the energy ray, and is applied to the adherend. It can be easily peeled off without applying stress and without residual adhesive. Examples of energy rays include ultraviolet rays and electron beams.

As the energy ray polymerizable compound, a compound having two or more energy ray polymerizable carbon-carbon double bonds in the molecule can be used. Examples of such compounds include polyfunctional acrylate compounds.
Examples of polyfunctional acrylate compounds include 1,4-butylene di (meth) acrylate, 1,5-pentanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, and 1,9-nonanediol. (Meth) acrylates of linear aliphatic polyols such as di (meth) acrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate;
(Meth) acrylates of aliphatic polyols having an alicyclic group such as cyclohexanedimethanol di (meth) acrylate and tricyclodecane dimethanol diacrylate;
(Meth) acrylates of branched aliphatic polyols such as trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, and their condensates (ditrimethylolpropane tetraacrylate, And dipentaerythritol hexaacrylate). You may use these individually or in combination of 2 or more types.

As the energy ray polymerizable compound, for example, a polyfunctional acrylate oligomer such as a urethane acrylate oligomer may be used.
The urethane acrylate oligomer is obtained, for example, by reacting a urethane oligomer obtained by the reaction of a diisocyanate compound and a polyol compound with a (meth) acrylic acid alkyl ester having a hydroxyl group.
Examples of the diisocyanate compound include tolylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, phenylene diisocyanate, dicyclohexylmethane diisocyanate, xylene diisocyanate, tetramethylxylene diisocyanate, naphthalene diisocyanate, and isophorone diisocyanate.

Examples of polyol compounds include ethylene glycol, 1,4-butanediol, 1,6-hexanediol, diethylene glycol, trimethylolpropane, dipropylene glycol, polyethylene glycol, polypropylene glycol, pentaerythritol, dipentaerythritol, and glycerin. Polyester polyol compound obtained by condensation reaction of alcohols, polyhydric alcohols and aliphatic dicarboxylic acids such as adipic acid, sebacic acid, azelaic acid, maleic acid or aromatic dicarboxylic acids such as terephthalic acid and isophthalic acid ;
Polyether polyol compounds such as polyethylene ether glycol, polypropylene ether glycol, polytetramethylene ether glycol, polyhexamethylene ether glycol;
Lactone polyol compounds such as polycaprolactone glycol, polypropiolactone glycol, polyvalerolactone glycol;
Examples thereof include polycarbonate polyol compounds obtained by dealcoholization reaction of polyhydric alcohols such as ethylene glycol, propylene glycol, butanediol, pentanediol, octanediol, and nonanediol with diethylene carbonate, dipropylene carbonate and the like. Examples of hydroxyl group-containing (meth) acrylic acid alkyl ester compounds include 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, and (meth) acrylic. 6-hydroxyhexyl acid, 8-hydroxyoctyl (meth) acrylate, 10-hydroxydecyl (meth) acrylate, 12-hydroxylauryl (meth) acrylate, (4-hydroxymethylcyclohexyl) methyl (meth) acrylate, etc. Can be mentioned.

  The energy beam polymerizable compound can be used in an amount of, for example, 5 to 200 parts by weight, preferably 10 to 100 parts by weight, and more preferably 10 to 45 parts by weight with respect to 100 parts by weight of the base polymer.

  As a method for introducing an energy beam polymerizable double bond into a base polymer, for example, when preparing an acrylic polymer as a base polymer, a copolymer having a reactive functional group such as a carboxyl group, a hydroxyl group, and an amino group And a method of copolymerizing a functional monomer. Thereby, a functional group serving as a base point of reaction is introduced into the base polymer, and a polyfunctional monomer or oligomer having an energy ray polymerizable carbon-carbon double bond is bonded via the functional group serving as the base point of the reaction. And a base polymer having an energy beam polymerizable carbon-carbon double bond in the side chain can be obtained.

The energy ray-curable pressure-sensitive adhesive may contain a photopolymerization initiator as necessary. The photopolymerization initiator is excited and activated by irradiation with energy rays to generate radicals, and promotes an efficient polymerization and curing reaction of the pressure-sensitive adhesive layer.
As the photopolymerization initiator, for example,
Benzoin alkyl ether initiators such as benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether;
Benzophenone initiators such as benzophenone, benzoylbenzoic acid, 3,3′-dimethyl-4-methoxybenzophenone, polyvinylbenzophenone;
α-hydroxycyclohexyl phenyl ketone, 4- (2-hydroxyethoxy) phenyl (2-hydroxy-2-propyl) ketone, α-hydroxy-α, α'-dimethylacetophenone, methoxyacetophenone, 2,2-dimethoxy-2- Aromatic ketone-based initiators such as phenylacetophenone and 2,2-diethoxyacetophenone;
Aromatic ketal initiators such as benzyldimethyl ketal;
Thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2-ethylthioxanthone, 2-isopropylthioxanthone, 2-dodecylthioxanthone, 2,4-dichlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2, Thioxanthone initiators such as 4-diisopropylthioxanthone, benzyl initiators such as benzyl, benzoin initiators such as benzoin, α-ketol compounds (such as 2-methyl-2-hydroxypropiophenone), aromatic sulfonyl chlorides Compounds (such as 2-naphthalenesulfonyl chloride), photoactive oxime compounds (such as 1-phenone-1,1-propanedione-2- (o-ethoxycarbonyl) oxime), camphorquinone, halogenated ketones, Sill phosphino, dimethylsulfoxide, and the like acyl phosphonium isocyanate is. You may use these individually or in combination of 2 or more types.

The pressure sensitive adhesive uses a polymer having an acidic group such as a carboxyl group as a base polymer, and a hydrophilicity is imparted by adding a neutralizing agent to neutralize all or part of the acidic groups in the base polymer. It is good also as an adhesive. The hydrophilic adhesive generally has little adhesive residue on the adherend, and even when adhesive residue is generated, it can be easily removed by washing with pure water.
The polymer having an acidic group is obtained by copolymerizing a monomer having an acidic group such as the above-mentioned carboxyl group-containing monomer when preparing the base polymer.
Examples of the neutralizing agent include primary amines such as monoethylamine and monoethanolamine, secondary amines such as diethylamine and diethanolamine, triethylamine, triethanolamine, N, N, N′-trimethylethylenediamine, N-methyldiethanolamine, Examples thereof include organic amino compounds exhibiting alkalinity, such as tertiary amines such as N, N-diethylhydroxylamine.

The pressure-sensitive adhesive may contain a crosslinking agent as required.
Examples of the crosslinking agent include an epoxy crosslinking agent, an isocyanate crosslinking agent, a melamine crosslinking agent, a peroxide crosslinking agent, a metal alkoxide crosslinking agent, a metal chelate crosslinking agent, a metal salt crosslinking agent, and a carbodiimide crosslinking. Crosslinkers such as an agent, an oxazoline crosslinker, an aziridine crosslinker, and an amine crosslinker can be used, and an epoxy crosslinker, an isocyanate crosslinker, and the like can be preferably used. You may use these individually or in combination of 2 or more types.
Examples of the epoxy crosslinking agent include N, N, N ′, N′-tetraglycidyl-m-xylenediamine, diglycidylaniline, 1,3-bis (N, N-glycidylaminomethyl) cyclohexane, 1,6. -Hexanediol diglycidyl ether, neopentyl glycol diglycidyl ether, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, sorbitol polyglycidyl ether, glycerol polyglycidyl ether, pentaerythritol Polyglycidyl ether, polyglycerol polyglycidyl ether, sorbitan polyglycidyl ether, trimethylolpropane polyglycidyl ether Ter, adipic acid diglycidyl ester, o-phthalic acid diglycidyl ester, triglycidyl-tris (2-hydroxyethyl) isocyanurate, resorcin diglycidyl ether, bisphenol-S-diglycidyl ether, two epoxy groups in the molecule The epoxy resin which has the above is mentioned.

  Examples of the isocyanate crosslinking agent include lower aliphatic polyisocyanates such as 1,2-ethylene diisocyanate, 1,4-butylene diisocyanate, and 1,6-hexamethylene diisocyanate; cyclopentylene diisocyanate, cyclohexylene diisocyanate, and isophorone diisocyanate. , Aliphatic polyisocyanates such as hydrogenated tolylene diisocyanate and hydrogenated xylene diisocyanate; aromas such as 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4′-diphenylmethane diisocyanate, xylylene diisocyanate Group polyisocyanates and the like.

The pressure-sensitive adhesive layer preferably contains a plasticizer. Examples of the plasticizer include the same ones as described above. The addition amount of the plasticizer in this case is suitably used in a ratio of, for example, 10 to 100 parts by weight, preferably 10 to 100 parts by weight with respect to 100 parts by weight of the thermoplastic resin constituting the pressure-sensitive adhesive. 80 parts by weight, more preferably 10 to 60 parts by weight is preferred.
The pressure-sensitive adhesive layer may further contain additives such as a stabilizer, a filler lubricant, a colorant, an ultraviolet absorber, an antioxidant, and a colorant as necessary. These additives include the same ones as described above.

The pressure-sensitive adhesive layer can be formed by applying the above-mentioned pressure-sensitive adhesive on a substrate by an appropriate method such as a knife coater, a roll coater, a gravure coater, a die coater, or a reverse coater. Further, for example, an adhesive layer may be formed on an appropriate casting process sheet such as a film having a release treatment applied to the surface, and the adhesive layer may be transferred onto the thermoplastic resin film.
The thickness of the pressure-sensitive adhesive layer is not particularly limited, but is preferably 5 to 100 μm, more preferably 5 to 60 μm, and particularly preferably 5 to 30 μm. When the thickness of the pressure-sensitive adhesive layer is within the above range, the stress of the thermoplastic resin film can be reduced and the stress relaxation rate of the pressure-sensitive adhesive tape can be improved.

  The pressure-sensitive adhesive tape of the present invention preferably has, for example, a silicon wafer adhesive force that is suppressed to a fluctuation value within ± 0.5 N / 20 mm before and after storage regardless of the storage state. From another point of view, it is preferable to suppress the fluctuation range within ± 70% of the initial value, preferably within 65%, and more preferably within ± 63%. By setting the fluctuation within such a range, it is possible to prevent the adhesive force of the adhesive tape from being lowered regardless of the storage state, there is no adhesive remaining on the adherend, and the adhesion from the adherend. Peeling can be easily performed. Here, the term “before storage” and “initial value” means immediately after the pressure-sensitive adhesive tape is manufactured or immediately after the adhesive sheet is manufactured and the release liner is brought into contact with the pressure-sensitive adhesive layer side. The term “after storage” usually means after about one week or more has elapsed since the production or when the release liner was brought into contact with the pressure-sensitive adhesive layer side.

  This adhesive tape can be used for various applications. For example, various members such as optical devices or films, products having a plate shape or curved surface made of resin, glass, metal, etc., for fixing wafers in semiconductor processes, for semiconductor back grinding, for semiconductor dicing, semiconductor package, glass It can be used as a pressure-sensitive adhesive tape that is attached (further removed) for dicing ceramics, etc., and for protecting circuit surfaces during these processes. For this reason, the pressure-sensitive adhesive tape of the present invention can have various shapes and sizes such as a shape suitable for these applications, for example, a sheet shape and a strip shape.

  Thus, the pressure-sensitive adhesive tape of the present invention contains both methylene bis-fatty acid amide and fatty acid in at least one of the thermoplastic resin film and the pressure-sensitive pressure-sensitive adhesive layer, resulting from the raw material / production method of methylene bis-fatty acid amide, etc. By containing substantially no fatty acid monoamide, problems caused by using commercially available methylene bis fatty acid amide can be unexpectedly solved. Furthermore, by containing a fatty acid in addition to methylene bis-fatty acid amide, it is possible to further balance the storage of the adhesive tape and the bonding and storage to the adherend. In other words, a sufficient adhesive force can always be obtained regardless of the storage state (that is, even by storage or processing at a high temperature). Furthermore, even if it is stored at a temperature of about 60 ° C. in a state of being attached to an adherend such as a silicon wafer (that is, regardless of the storage state after the adherend is bonded), it tries to peel off from the adherend again. In this case, it is possible to effectively prevent such a problem that the adhesive force is increased and it is difficult to peel off or the adhesive remains on the adherend.

(Release liner)
In the pressure-sensitive adhesive tape of the present invention, in order to protect the pressure-sensitive adhesive layer, a release liner may be disposed on the pressure-sensitive adhesive layer side in contact with the pressure-sensitive adhesive layer.
As a release liner, if it is normally used in the said field | area, it can be used without being specifically limited. For example, paper, rubber, aluminum foil, copper foil, stainless steel foil, iron foil, duralumin foil, tin foil, titanium foil, various metal foils such as gold foil, and various resins such as polyethylene, polypropylene, polyvinyl chloride, polyester, polyamide Films, foams such as polyurethane foam, vinyl foam, polyethylene foam, styrene foam, non-woven fabrics, woven fabrics, felts, and films obtained by laminating these with polymer materials can be used as the substrate. The thickness of a base material is not specifically limited, For example, it is appropriate to set it as 5 micrometers-5 mm, Preferably about 30 micrometers-100 micrometers.
On the surface of such a substrate that is in contact with the pressure-sensitive adhesive layer, silicone resin, long chain alkyl resin, fluorine resin, low molecular weight polyethylene, polypropylene, rubber polymer, phosphate ester surfactant, etc. Examples include those subjected to a release treatment known in the art, such as applying a mold in a layer form.
The release liner has one or more straight, wavy, serrated, and jagged slits (so-called back cuts) in order to improve the sticking operability when sticking the adhesive tape to the adherend. Also good.

[Production method of adhesive tape]
The pressure-sensitive adhesive tape of the present invention uses a methylene bis fatty acid amide obtained by the reaction of a fatty acid amide and formaldehyde, preferably a solvent that dissolves the fatty acid monoamide and the fatty acid constituting it, but does not dissolve the methylene bis fatty acid amide. Obtained methylene bis fatty acid amide purified by extraction,
Adding the methylene bis-fatty acid amide and the fatty acid to the resin to form a thermoplastic resin film or a pressure-sensitive adhesive layer;
It can manufacture by laminating | stacking the said thermoplastic resin film and a pressure sensitive adhesive layer.

A method of forming a thermoplastic resin film or a pressure-sensitive adhesive layer by adding methylene bis fatty acid amide as an additive to a resin or the like, a method of forming a thermoplastic resin film or a pressure-sensitive adhesive layer by adding a fatty acid, Methods known in the art can be used.
In addition, you may perform sequentially formation and lamination | stacking of such a thermoplastic resin film or a pressure sensitive adhesive layer. That is, you may form a thermoplastic resin film and a pressure-sensitive adhesive layer independently by the method well-known in the said field | area. For this purpose, for example, a melt extrusion method (an inflation method, a T-die method, etc.), a melt casting method, a calendar method, or the like can be used. The pressure-sensitive adhesive layer may be separately formed by the method described above. Thus, when a thermoplastic resin film and a pressure sensitive adhesive layer are formed independently, both can be laminated | stacked by a well-known method in the said field | area.

The formation and lamination of the thermoplastic resin film or the pressure-sensitive adhesive layer may be performed simultaneously. That is, a thermoplastic resin film and a pressure-sensitive adhesive layer are multilayered by a co-extrusion method, a laminating method (extrusion laminating method, a laminating method using an adhesive, etc.), or a heat sealing method (external heating method, internal heating method, etc.). It may be formed as a structure.
The release liner can usually be obtained by forming a pressure-sensitive adhesive tape and then sticking it to the pressure-sensitive adhesive layer side to obtain a pressure-sensitive adhesive tape with a release liner.

(Preparation of purified methylene bis fatty acid amide)
A commercially available methylene bis fatty acid amide (manufactured by Nippon Kasei Co., Ltd.) was prepared.
About this methylene bis fatty acid amide, content of each component was measured on condition of the following using HPLC. The results are shown as “Before extraction: bisamide A” in Table 1.

About this methylene bis fatty acid amide, the fatty acid monoamide and the fatty acid constituting the fatty acid monoamide were removed.
Specifically, 40 ml of chloroform was added to about 1 g of methylene bis fatty acid amide, and the mixture was soaked for 1 hour using a soaking machine. Then, it isolate | separated into the insoluble part and the soluble part by suction filtration. About the obtained chloroform insoluble matter, the same operation was performed twice, respectively, and the high purity methylenebis fatty acid amide was obtained.
About the obtained methylenebis fatty acid amide, it analyzed under the following conditions using HPLC. The results are shown as “After extraction: Bisamide B” in Table 1.

Analysis by HPLC of methylene bis fatty acid amide and the like was performed as follows.
First, about 0.5 g of methylene bis-fatty acid amide was sampled and immersed in a mixed solvent of chloroform and acetonitrile for about 1 day, and then the supernatant was filtered through a 0.45 μm membrane filter to obtain an HPLC apparatus ( Waters, W2695 / W2420).
HPLC conditions Column: Inertsil C8-3 (4.6mm × 150mm, 5μm)
Flow rate: 1.0ml / min
Detector: ELS
Column temperature: 40 ° C
Injection volume: 30 μl
Grain: 30
Drift tube temperature: 50 ° C
Gas pressure: 40psi
Eluent component: Gradient (min) 0 → 20 → 40
A: 0.1% TFA aqueous solution A% 50 → 0 → 0
B: Acetonitrile B% 50 → 100 → 100

(Creation of adhesive tape)
The following raw materials were prepared and blended in advance with a Henschel mixer, and the plasticizer was soaked in the resin and dried up. Using a polyvinyl chloride mixture obtained by kneading this with a Banbury mixer, a thermoplastic resin film having a thickness of 110 μm was obtained by a calender film forming machine.
As the lubricant, methylene bis fatty acid amide and fatty acid shown in Table 2 were used. The lubricant was added when kneading the Banbury mixer.

Thermoplastic resin: Polyvinyl chloride resin (average polymerization degree 1050) 100 parts by weight Plasticizer: Diethylhexyl phthalate 30 parts by weight Stabilizer: Ba-Zn mixed stabilizer 3 parts by weight Lubricant 0.7 parts by weight

An adhesive was prepared with the following composition.
Acrylic polymer (butyl acrylate / acrylonitrile / acrylic acid = 84/14/2)
100 parts by weight Plasticizer: Diethylhexyl phthalate 20 parts by weight Crosslinking agent: Butylated melamine resin 10 parts by weight The obtained pressure-sensitive adhesive was diluted to 20% with toluene, and the thickness after drying was 10 μm. It apply | coated to the thermoplastic resin film, and wound up in roll shape through the drying process of 150 degreeC and 1 minute.
Thereafter, aging was performed at 50 ° C. for 24 hours, and the film was attached to a release liner (silicone-treated polyester film, MRF, 38 μm (manufactured by Mitsubishi Plastics)) and wound up.

The following evaluation was performed using the obtained adhesive tape.
1) Evaluation of heat storage adhesive strength after bonding silicon wafers A test piece cut to a width of 20 mm and a length of 100 mm was attached to a silicon wafer, stored for one week in a dryer at 60 ° C., and then left at room temperature for 1 hour. The adhesive strength was measured under the following conditions.
Measuring device: Instron type tensile tester AUTOGRAPH AG-IS made by Shimadzu Corporation
Measurement atmosphere: 23 ° C., 50% RH
Substrate: 8-inch mirror wafer Bonding condition: 1 reciprocation with 2 kg roller Measurement condition: 90 ° peel, 300 mm / min
Acceptance / rejection determination: A value within ± 0.5 N / 20 mm from the initial value was accepted.

2) Evaluation of wafer surface contamination after adhesion test (after storage at 60 ° C for 1 week)
The retrofit (contamination) on the wafer surface after the adhesion test was evaluated according to the following criteria.
5: No back-up 4: Lightly visible on the entire surface (not visible without staring)
3: Can be confirmed without staring (blackish back)
2: Appears to be cloudy in white 1: A clear white tail can be confirmed (to the extent that lump can be removed by rubbing)
A black contamination with an evaluation of 3 or more was accepted.
These results are shown in Table 2.

ステアリン酸：試薬グレード 95％以上
パルミチン酸：試薬グレード 95％以上
ステアリン酸モノアミド：試薬グレード 95％以上
パルミチン酸モノアミド：試薬グレード 95％以上

Stearic acid: Reagent grade 95% or higher Palmitic acid: Reagent grade 95% or higher Stearic acid monoamide: Reagent grade 95% or higher Palmitic acid monoamide: Reagent grade 95% or higher

  The pressure-sensitive adhesive tape of the present invention can be widely used as a surface protection tape or sheet for various adherends such as electronic parts, a processing tape for protection during dicing, or a protection tape or sheet.

Claims (8)

  A pressure-sensitive adhesive tape in which a pressure-sensitive adhesive layer is formed on one side of a thermoplastic resin film, and at least one of the thermoplastic resin film and the pressure-sensitive adhesive layer contains methylene bis fatty acid amide and a fatty acid, A pressure-sensitive adhesive tape characterized by substantially not containing a fatty acid monoamide, which is a by-product during the production of methylene bis-fatty acid amide.   The pressure-sensitive adhesive tape according to claim 1, wherein the methylene bis fatty acid amide is obtained by removing the fatty acid monoamide as the by-product by solvent extraction. The pressure-sensitive adhesive tape according to claim 1 or 2, wherein the methylene bis fatty acid amide is a compound represented by the formula (I).
_{^{R 1 -Am-CH 2 -Am-}} R 2 (I)
(In the formula, R ¹ and R ² each independently represents a saturated or unsaturated hydrocarbon group having 6 to 23 carbon atoms, and Am represents a secondary amide group.)   The pressure-sensitive adhesive tape according to any one of claims 1 to 3, wherein the fatty acid is contained in an amount of 0.1 to 30 parts by weight with respect to 100 parts by weight of methylene bis fatty acid amide.   The pressure-sensitive adhesive tape according to any one of claims 1 to 4, wherein the methylene bis-fatty acid amide and the fatty acid are each contained in an amount of 0.1 to 5.0 parts by weight with respect to 100 parts by weight of the thermoplastic resin.   The pressure-sensitive adhesive tape according to any one of claims 1 to 5, wherein the thermoplastic resin film is a film made of soft polyvinyl chloride containing a plasticizer.   The pressure-sensitive adhesive layer according to any one of claims 1 to 6, wherein the pressure-sensitive pressure-sensitive adhesive layer contains an acrylic polymer as a base polymer.   The pressure-sensitive adhesive tape according to any one of claims 1 to 7, wherein a release liner is disposed on the pressure-sensitive pressure-sensitive adhesive layer side of the pressure-sensitive adhesive tape.