JP2008004679A - Substrate film for dicing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate film for dicing which does not almost have occurrence of cut waste (waste of a thread shape or a whisker shape, which is caused from film after dicing) in a dicing process. <P>SOLUTION: The substrate film for dicing comprises thermoplastic elastomer composition where rubber particles bridged in thermoplastic resin are slightly dispersed. An average particle size of the bridged rubber particles is 0.1 to 50 μm. An average value of a ratio of an area of the bridged rubber particles is 1 to 75% with respect to an area of thermoplastic resin in a film face. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a dicing film for fixing a semiconductor wafer or the like when the semiconductor wafer or the like is diced into chips.

  The semiconductor wafer is made in advance with a large area, then diced into chips (cut and separated), and transferred to the mounting process. In the dicing, a dicing film is used for fixing the semiconductor wafer.

  The dicing film is basically composed of an adhesive layer for fixing the semiconductor wafer and a resin layer (a substrate film for dicing) that receives the cutting of the dicing cutter. The semiconductor wafer fixed to the dicing film is diced into chips.

  In the dicing process of the semiconductor wafer, the adhesive layer or a part of the substrate film for dicing is cut together with the wafer to generate cutting waste (dicing waste). Since this cutting waste contaminates the wafer and lowers the yield of chips, it is necessary to reduce it as much as possible.

  For example, the following dicing film has been reported mainly for the purpose of eliminating cutting waste in the dicing process.

  Patent Document 1 describes a polyolefin film such as polyethylene irradiated with 1 to 80 Mrad of an electron beam or γ-ray as a base film. However, since this film crosslinks the entire crosslinkable resin with an electron beam or the like, it becomes hard and sufficient expandability cannot be obtained.

  Patent Document 2 describes an ethylene / methyl methacrylate copolymer film as a base film. However, although this film can reduce a certain amount of cutting waste, it is not always sufficient.

  Patent Document 3 mainly discloses a resin layer B mainly composed of an ionomer resin obtained by crosslinking a terpolymer of ethylene, (meth) acrylic acid, and a (meth) acrylic acid alkyl ester with a metal ion, and an adhesive layer. A semiconductor wafer fixing adhesive tape laminated with A is described. However, since this film contains metal ions, contamination of the wafer becomes a problem.

  Patent Document 4 discloses a resin in which an adhesive coated layer, a thermoplastic elastomer layer, and a resin layer are laminated in this order, and the thermoplastic elastomer layer contains 70% by mass or more of a hydrogenated styrene-butadiene copolymer. An adhesive tape base material comprising a composition and having a layer thickness of 30% or more with respect to the base material thickness is described. However, this film does not always have a sufficient cutting scrap reduction effect.

By the way, in Patent Document 5, a softener, an olefin resin (polypropylene, etc.), a 1,2-polybutadiene elastomer (polybutadiene, SBS, etc.), and an organic peroxide are added to a polystyrene copolymer such as SEBS. A so-called dynamic cross-linkable elastomer composition is obtained. This elastomer composition has excellent heat resistance and oil resistance.
Japanese Patent Laid-Open No. 5-21234 JP-A-5-156214 Japanese Patent Laid-Open No. 9-8111 JP 2005-272724 A JP 2002-173574 A

  The main object of the present invention is to provide a substrate film for dicing that hardly generates cutting waste (thread-like or whisker-like waste generated from the film after dicing) in the dicing process.

  As a result of diligent research to solve the above-mentioned problems, the present inventor made a thermoplastic resin such as polyolefin resin and polystyrene resin as a matrix (sea phase), and the domain ( It was found that the film in which the island phase is dispersed hardly generates cutting waste during dicing. Based on this knowledge, further studies have been made and the present invention has been completed.

  That is, the present invention provides the following substrate film for dicing.

  Item 1. A substrate film for dicing comprising a thermoplastic elastomer composition in which rubber particles crosslinked in a thermoplastic resin are finely dispersed.

  Item 2. Item 2. The substrate film for dicing according to Item 1, wherein the average particle size of the crosslinked rubber particles is 0.1 to 50 μm.

  Item 3. Item 3. The substrate film for dicing according to Item 1 or 2, wherein the average value of the area ratio of the crosslinked rubber particles to the area of the thermoplastic resin is 1 to 75%.

  Item 4. Item 1-3, wherein the thermoplastic elastomer composition is a crosslinked composition obtained by dynamically crosslinking a resin composition containing a thermoplastic resin, a crosslinkable copolymer rubber, and a softening agent in the presence of a crosslinking agent. The substrate film for dicing according to any one of the above.

  Item 5. Item 5. The substrate film for dicing according to Item 4, wherein the crosslinkable copolymer rubber is an olefin copolymer rubber or a styrene copolymer rubber.

  Item 6. Item 6. The substrate film for dicing according to any one of Items 1 to 5, wherein the thermoplastic resin is a polyolefin resin and / or a polystyrene resin.

  Item 7. Item 7. The dicing product according to Item 6, wherein the polyolefin-based resin is at least one selected from the group consisting of branched low-density polyethylene, linear low-density polyethylene, high-density polyethylene, polypropylene, and propylene-α-olefin copolymer. Base film.

  Item 8. The polystyrene resin is at least one selected from the group consisting of a styrene homopolymer, a styrene-butyl acrylate copolymer, a styrene-conjugated diene block copolymer, and a hydrogenated styrene-conjugated diene block copolymer. Item 7. A substrate film for dicing according to Item 6.

  Item 9. Item 9. A dicing film further comprising an adhesive layer on the substrate film for dicing according to any one of Items 1 to 8.

Hereinafter, the present invention will be described in detail.
I. Dicing Substrate Film The dicing substrate film of the present invention comprises a thermoplastic elastomer composition (hereinafter referred to as “TPE”) in which domains (island phases) of crosslinked rubber particles are finely dispersed in a thermoplastic resin matrix (sea phase). Composition ”).

  This thermoplastic elastomer composition comprises (i) a thermoplastic resin, (ii) a crosslinkable copolymer rubber, and (iii) a softening agent, and (iv) dynamic crosslinking in the presence of a crosslinking agent. Is obtained.

The dynamic crosslinking means that a copolymerizable rubber is blended into a thermoplastic resin matrix and crosslinked while being kneaded in a molten state or a semi-molten state. Thereby, a thermoplastic elastomer composition in which crosslinked rubber particles are dispersed microscopically in a matrix is obtained.
(I) Thermoplastic resin The thermoplastic resin is not particularly limited as long as it can be used as a substrate for dicing, and examples thereof include polyolefin resins and / or polystyrene resins.

  Examples of the polyolefin-based resin include branched low-density polyethylene, linear low-density polyethylene, high-density polyethylene, polypropylene, and propylene-α-olefin copolymers. You may mix and use the above. Examples of the α-olefin include α-olefins having 2 or more carbon atoms (excluding 3 carbon atoms), such as ethylene, 1-butene, 1-hexene, 1-pentene, and 1-octene. 1-decene and the like.

  Examples of polystyrene resins include styrene homopolymers, styrene-butyl acrylate copolymers, styrene-conjugated diene block copolymers, and hydrogenated products of styrene-conjugated diene block copolymers. Each may be used alone or in combination of two or more. Examples of the conjugated diene include butadiene, isoprene, 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene, and the like, and butadiene and isoprene are particularly preferable.

Of the above thermoplastic resins, hydrogenated styrene-conjugated diene block copolymers are preferred.
(Ii) Crosslinkable copolymer rubber The crosslinkable copolymer rubber is not particularly limited as long as it can be finely dispersed in the matrix in the form of particles after crosslinking. For example, olefin copolymer rubber and styrene copolymer are usable. Rubber etc. are mentioned.
(Ii-1) Olefin copolymer rubber Examples of the olefin copolymer rubber include ethylene-α-olefin copolymer rubber, ethylene-α-olefin-nonconjugated diene copolymer rubber, isobutylene-isoprene copolymer rubber, and acrylonitrile. -Butadiene copolymer rubber, natural rubber, silicon rubber, isoprene rubber, polybutadiene, acrylic rubber, chloroprene rubber, and hydrogenated products, halides, and functional group-modified products of the above rubbers. Of these, isobutylene-isoprene copolymer rubber, ethylene-α-olefin copolymer rubber, ethylene-α-olefin-nonconjugated diene copolymer rubber, and acrylonitrile-butadiene copolymer rubber are preferable.

  Ethylene-α-olefin copolymer rubber and ethylene-α-olefin-nonconjugated diene copolymer rubber (hereinafter also referred to as “ethylene copolymer rubber”), which are preferably used as a crosslinkable copolymer rubber, are ethylene. And a random copolymer rubber obtained by copolymerizing an α-olefin having 3 or more carbon atoms and a non-conjugated diene with these. Examples of the α-olefin having 3 or more, preferably 3 to 10 carbon atoms copolymerized with ethylene include propylene, 1-hexene, 1-butene, 1-hexene, 1-pentene, 1-octene, 1-decene and the like. Can be mentioned. Two or more α-olefins having 3 or more carbon atoms may be used.

Specific examples of the non-conjugated diene include dicyclopentadiene, 1,4-hexadiene, 1,9-decadiene, cyclooctadiene, norbornadiene, methylene norbornene, ethylidene norbornene, and 7-methyl-1,6-octadiene. Can be mentioned. It is also possible to give a branched structure to the ethylene-α-olefin-nonconjugated diene copolymer by a known method. As preferred dienes for imparting a branched structure, 1,9-decadiene, norbornadiene and the like can be mentioned. The preferable content of the non-conjugated diene component in the ethylene-α-olefin-non-conjugated diene copolymer is 5 to 50, more preferably 10 to 45 in terms of iodine value.
(Ii-2) Styrenic copolymer rubber As the styrene copolymer rubber, for example, a block copolymer represented by the formula: A- (BA) n and / or the formula: (AB) n, Examples thereof include hydrogenated products. Here, A is a polymer block of vinyl aromatic hydrocarbon (hereinafter “A block”), B is an elastomeric polymer block (hereinafter “B block”), and n is an integer of 1 to 5. .

  In the block copolymer, the A block constitutes a hard segment and the B block constitutes a soft segment. Typical examples are formula: AB or formula: ABA, and a triblock of formula: ABA is particularly preferred. These are block copolymers in which the unsaturated double bond of the B block is hydrogenated.

  Examples of the vinyl aromatic hydrocarbon constituting the A block include styrene, α-methylstyrene, nucleus-substituted methylstyrene, 1,3-dimethylstyrene, vinylnaphthalene, vinylanthracene and the like. In particular, styrene alone or styrene as a main component is preferable. As the remaining component when styrene is a main component, α-methylstyrene, maleic anhydride, and the like are preferable.

  The B block is preferably a hydrogenated product of a conjugated diene homopolymer block or a hydrogenated polymer block containing a conjugated diene as a main component. Examples of the conjugated diene include butadiene, isoprene, 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene and the like. In particular, butadiene, isoprene or a mixture of both is preferred.

The B block hydrogenation rate of the styrene copolymer rubber is usually 80 to 99.9%, preferably 85 to 99.8%, and more preferably 90 to 99.6%. When the hydrogenation rate is less than the above range, there are too many unsaturated double bonds to be cross-linked, and a large amount of cross-linking agent is required. Is slightly improved in the crosslinking properties of the composition obtained by lack of unsaturated double bonds available for crosslinking.
(Iii) Softener In the present invention, a softener is added to adjust the hardness of the elastomer composition. Examples of the softening agent used include paraffinic and aromatic mineral oils, silicone oils, vegetable oils, and the like. The softening agent is added in an amount of about 20 to 350 parts by weight, preferably about 40 to 250 parts by weight, based on 100 parts by weight of the total copolymer rubber that can be crosslinked with the thermoplastic resin.
(Iv) Crosslinking agent Examples of the crosslinking agent include ketone peroxides, peroxyketals, hydroperoxides, dialkyl peroxides, diacyl peroxides, peroxyesters and other organic peroxides, N-phenylmaleimide, N- Examples thereof include monomaleimides such as (2-chlorophenyl) maleimide, sulfur, sulfur compounds, quinone derivatives, and epoxy compounds.

A crosslinking agent is added about 0.5-20 weight part with respect to 100 weight part of thermoplastic resins, Preferably about 1-10 weight part is added.
(V) Others In the present invention, a crosslinking aid may be used as necessary. As the crosslinking aid, not a monomer but a 1,2-polybutadiene elastomer is used. By using such a polymer cross-linking aid, the formation of cross-linking is performed gently, the composition can be uniformly kneaded, and the moldability is greatly improved.

  Examples of the 1,2-polybutadiene elastomer include styrene / butadiene / styrene block copolymer (SBS), styrene / butadiene rubber (SBR), 1,2-polybutadiene, 1,4-polybutadiene, and 1,2-polybutadiene. Examples thereof include a mixture with 1,4-polybutadiene. About 0.1 to 50 parts by weight of the crosslinking aid is added to 100 parts by weight of the thermoplastic resin.

  Further, various thermoplastic resins and rubbers other than the above, glass fiber, carbon fiber, potassium titanate fiber, talc, mica, silica, titania, calcium carbonate, carbon black, etc. within the range not impairing the object of the present invention Fillers, as well as antioxidants, heat stabilizers, light stabilizers, UV absorbers, neutralizers, lubricants, antifogging agents, petroleum resins, antiblocking agents, antistatic agents, dispersants, flame retardants, conductive It may contain a property-imparting agent, molecular weight modifier, antibacterial agent, antifungal agent, fluorescent whitening agent, colorant and the like. These can be preliminarily contained in any of the essential components (i) to (iv), or can be blended during uniform mixing, melt-kneading, or dynamic heat treatment.

  These components can be added, for example, about 0 to 5 parts by weight, preferably about 0 to 2 parts by weight, with respect to 100 parts by weight of the thermoplastic resin.

  A thermoplastic elastomer composition obtained by dynamically crosslinking (iv) a resin composition containing (i) a thermoplastic resin, (ii) a crosslinkable copolymer rubber, and (iii) a softening agent in the presence of a crosslinking agent. As a method for obtaining a product, for example, the following method is exemplified.

  To prepare the thermoplastic elastomer composition, melt and knead the thermoplastic resin, crosslinkable copolymer rubber, softener, and other components as necessary, and then add a crosslinking aid and melt knead. A method of kneading by adding a crosslinking agent, or melt-kneading a thermoplastic resin, a crosslinkable copolymer rubber, a softening agent, a crosslinking aid, and other components as necessary, and then adding a crosslinking agent. The method of kneading is mentioned. The melt kneading temperature is usually set to 180 to 220 ° C. Thus, by adding the cross-linking agent after melt-kneading the components other than the cross-linking agent first, the components other than the cross-linking agent are uniformly kneaded before the cross-linking reaction. A crosslinking reaction can be performed to prevent localization of the crosslinking reaction.

  As described above, a desired thermoplastic elastomer composition can be obtained by adjusting the blending amount of the crosslinkable copolymer rubber as a raw material at the stage of dynamic crosslinking, but once prepared, the thermoplastic elastomer composition or Commercially available dynamically crosslinked thermoplastic elastomers can be further blended with the same or different thermoplastic resins and diluted to adjust the content of the crosslinked rubber particles in the composition to a desired range. Examples of commercially available dynamic cross-linkable thermoplastic elastomers include, for example, Thermolan, Lavalon manufactured by Mitsubishi Chemical Corporation, EXCELLINK manufactured by JSR Corporation, and elastomer AR manufactured by Aron Kasei Co., Ltd. .

  The above melt-kneaded or blended thermoplastic elastomer composition is supplied to a screw extruder, extruded from a single-layer T-die at 200 to 225 ° C., and passed through a cooling roll at 50 to 70 ° C. While cooling, it is taken up substantially unstretched. Thereby, a substrate film for dicing is manufactured.

  Alternatively, the melt-kneaded or blended thermoplastic elastomer composition may be once obtained as pellets and then extruded as described above.

  The reason why the film is substantially unstretched at the time of taking is to effectively extend the film after dicing. This substantially non-stretching includes non-stretching or slight stretching that does not adversely affect the expansion of the dicing film. In general, the film may be pulled to such an extent that no sagging occurs during film take-up.

  The average particle size of the crosslinked rubber particles in the thermoplastic elastomer composition is about 0.1 to 50 μm, preferably about 0.1 to 10 μm. When the average particle diameter of the crosslinked rubber particles is 0.1 to 50 μm, cutting waste can be efficiently suppressed.

  The average value of the area ratio of the crosslinked rubber particles to the area of the thermoplastic resin on the film surface is 1 to 75%, preferably 2 to 60%. When the area ratio is smaller than 1, the effect of suppressing cutting waste is not exhibited, and when it is larger than 75%, film forming becomes difficult, which is not preferable.

  The average value of the average particle diameter of the rubber particles and the ratio of the area of the crosslinked rubber particles to the area of the thermoplastic resin can be measured by the method described in Test Example 2.

  The thickness of the substrate film for dicing may be at least thicker than the cutting depth of the dicer and can be easily wound in a roll shape, for example, about 60 to 300 μm, preferably 60 to It is adjusted to about 250 μm.

  Since the crosslinked rubber particles are finely dispersed in the matrix, the dicing substrate film of the present invention is a dicing substrate film in which cutting waste is hardly generated in the dicing process.

  As described above, the single-layer dicing substrate film containing the thermoplastic elastomer composition has been described. However, a multi-layer dicing substrate film in which other resins are laminated may be used. Examples of other resins include polyolefin resins such as polyethylene resins, polypropylene resins, polymethylpentene resins, and cyclic olefin resins, and polyethylene resins are particularly preferable. In addition, all of multilayering of a film can be performed using a well-known method.

  The thickness of the thermoplastic elastomer composition of the base film for multi-layer (two-layer) dicing should be at least thicker than the cut depth of the dicer and can be easily wound into a roll. It is adjusted to about ˜300 μm, preferably about 60 to 250 μm.

  In the base film for multi-layer dicing that includes the polyolefin resin as the outermost layer, the blocking resistance is remarkably improved. Therefore, it functions as an anti-blocking layer that prevents blocking when winding on a roll. Therefore, the thickness of the layer is not particularly limited as long as it exhibits blocking resistance without impairing the performance of the layer of the thermoplastic elastomer composition, and is adjusted to, for example, 10 to 100 μm, preferably 20 to 60 μm.

A multi-layer dicing substrate film is manufactured using a multi-layer coextrusion method. Specifically, the above-described dynamically crosslinked thermoplastic elastomer composition is dry blended or melt kneaded and uniformly mixed and dispersed. Further, other resins are dry blended or melt kneaded to uniformly mix and disperse. Next, each obtained mixture is supplied to a screw type extruder, extruded from a multilayer T die at 200 to 225 ° C., and cooled while passing through a cooling roll at 50 to 70 ° C. Take it unstretched. The above-described substantially non-stretching is also synonymous with the method for producing a single layer film.
II. Dicing film The substrate film for dicing obtained as described above is coated with a known pressure-sensitive adhesive on the film to form a pressure-sensitive adhesive layer, and a release layer is further formed on the pressure-sensitive adhesive layer. A film is produced. In the case of a multi-layer dicing substrate film, an adhesive layer and a release layer are formed on a layer containing a thermoplastic elastomer composition in which rubber particles crosslinked in a thermoplastic resin are finely dispersed.

  As the pressure-sensitive adhesive component used in the pressure-sensitive adhesive layer, known ones are used, and for example, the pressure-sensitive adhesive component described in JP-A No. 5-21234 can be used. A known release layer is also used.

The pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer is preferably an acrylic pressure-sensitive adhesive. Specifically, the pressure-sensitive adhesive layer was selected from a homopolymer and a copolymer having (meth) acrylic acid ester as a main constituent monomer unit. Acrylic polymers, copolymers with other functional monomers, and mixtures of these polymers are used. For example, (meth) acrylic acid ester includes ethyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, glycidyl methacrylate, 2-hydroxyethyl methacrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, Glycidyl acrylate, 2-hydroxyethyl acrylate and the like can be preferably used. The molecular weight of the acrylic polymer is ^{1.0 × 10 5 ~10.0 × 10 5} , ^{preferably, 4.0 × 10 5 ~8.0 × 10} 5.

  Further, by including a radiation polymerizable compound in the pressure-sensitive adhesive layer as described above, the adhesive strength can be reduced by irradiating the pressure-sensitive adhesive layer with radiation after the wafer is cut and separated. As such a radiation polymerizable compound, for example, a low molecular weight compound having at least two photopolymerizable carbon-carbon double bonds in a molecule that can be three-dimensionally reticulated by light irradiation is widely used (for example, JP JP-A-60-196,956, JP-A-60-223,139, etc.).

  Specifically, trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol monohydroxypentaacrylate, dipentaerythritol hexaacrylate or 1,4-butylene glycol diacrylate, 1,6-hexanediol diacrylate, polyethylene glycol diacrylate, commercially available oligoester acrylate, and the like are used.

  Furthermore, in addition to the acrylate compounds as described above, urethane acrylate oligomers can also be used as the radiation polymerizable compound. The urethane acrylate oligomer is obtained by reacting an acrylate or methacrylate having a hydroxyl group with a terminal isocyanate urethane prepolymer obtained by reacting a polyol compound such as a polyester type or a polyether type with a polyvalent isocyanate compound. This urethane acrylate oligomer is a radiation polymerizable compound having at least one carbon-carbon double bond.

  Further, in the pressure-sensitive adhesive layer, in addition to the above-mentioned pressure-sensitive adhesive and radiation-polymerizable compound, if necessary, a compound that is colored by radiation irradiation (such as a leuco dye), a light-scattering inorganic compound powder, abrasive grains (A particle size of about 0.5 to 100 μm), an isocyanate curing agent, a UV initiator, and the like can also be contained.

  The dicing film is usually obtained in a rolled state cut into a tape shape.

  Since the substrate film for dicing of the present invention contains rubber particles crosslinked in the substrate film, there is almost no generation of cutting waste in the dicing process, so there is no concern about contamination of the wafer.

  Hereinafter, the present invention will be described in more detail using Examples and Comparative Examples, but the present invention is not limited to these Examples.

Example 1
A styrene-butadiene block copolymer hydrogenated product (SEBS resin, Asahi Kasei Chemicals Corporation, Tuftec H1062) 95% by weight and a dynamically crosslinked elastomer (Aron Kasei Co., Ltd. elastomer AR 9060) 5% by weight were dry blended. This was supplied to a single-screw extruder having a barrel temperature of 180 to 220 ° C., extruded from a single-layer T die having a temperature of 230 ° C., cooled and solidified by a take-up roll having a set temperature of 60 ° C., and wound in an unstretched state. The thickness of the obtained film was 150 μm.

Example 2
A film was prepared in the same manner as in Example 1 except that 90% by weight of the hydrogenated styrene-butadiene block copolymer and 10% by weight of the dynamically crosslinked elastomer were used.

Example 3
A film was produced in the same manner as in Example 1 except that 80% by weight of a styrene-butadiene block copolymer hydrogenated product and 20% by weight of a dynamically crosslinked elastomer were used.

Example 4
A film was prepared in the same manner as in Example 1, except that 70% by weight of the hydrogenated styrene-butadiene block copolymer and 30% by weight of the dynamically crosslinked elastomer were used.

Comparative Example 1
A film was produced in the same manner as in Example 1 except that the hydrogenated styrene-butadiene block copolymer was 100% by weight.

Example 5
95% by weight of a polypropylene resin (PP resin, Sun Allomer PC412, manufactured by Sun Allomer Co., Ltd.) and 5% by weight of a dynamically crosslinked elastomer (Elastomer AR 9060, manufactured by Aron Kasei Co., Ltd.) were dry blended. This was supplied to a single-screw extruder having a barrel temperature of 180 to 220 ° C., extruded from a single-layer T die having a temperature of 230 ° C., cooled and solidified by a take-up roll having a set temperature of 60 ° C., and wound in an unstretched state. The thickness of the obtained film was 150 μm.

Example 6
A film was produced in the same manner as in Example 5 except that 90% by weight of the polypropylene resin and 10% by weight of the dynamically crosslinked elastomer (elastomer AR 9060) were used.

Example 7
A film was produced in the same manner as in Example 5 except that 80% by weight of polypropylene resin and 20% by weight of dynamically crosslinked elastomer (elastomer AR 9060) were used.

Example 8
A film was prepared in the same manner as in Example 5 except that 70% by weight of polypropylene resin and 30% by weight of dynamically crosslinked elastomer (elastomer AR 9060) were used.

Comparative Example 2
A film was produced in the same manner as in Example 5 except that the polypropylene resin was 100% by weight.

Example 9
47.5% by weight of polypropylene resin (PP resin, Sun Allomer PC412 manufactured by Sun Allomer Co., Ltd.), 47.5% by weight of amorphous polypropylene resin (Amorphous PP resin, Tough Selenium T3512 manufactured by Sumitomo Chemical Co., Ltd.) and dynamic crosslinking Type elastomer (Aron Kasei Co., Ltd. elastomer AR 9060) 5% by weight was dry blended. This was supplied to a single-screw extruder having a barrel temperature of 180 to 220 ° C., extruded from a single-layer T die having a temperature of 230 ° C., cooled and solidified by a take-up roll having a set temperature of 60 ° C., and wound in an unstretched state. The thickness of the obtained film was 150 μm.

Example 10
A film was prepared in the same manner as in Example 9 except that the content was 45% by weight of polypropylene resin, 45% by weight of amorphous polypropylene resin, and 10% by weight of dynamically cross-linked elastomer (elastomer AR 9060).

Example 11
A film was prepared in the same manner as in Example 9, except that the content was 40 wt% polypropylene resin, 40 wt% amorphous polypropylene resin, and 20 wt% dynamically cross-linked elastomer (elastomer AR 9060).

Example 12
A film was produced in the same manner as in Example 9 except that 35% by weight of polypropylene resin, 35% by weight of amorphous polypropylene resin, and 30% by weight of dynamically crosslinked elastomer (elastomer AR 9060).

Comparative Example 3
A film was produced in the same manner as in Example 9 except that 50% by weight of the polypropylene resin and 50% by weight of the amorphous polypropylene resin were used.

Example 13
A styrene-butadiene block copolymer hydrogenated product (SEBS resin, Asahi Kasei Chemicals Corporation, Tuftec H1062) 95% by weight and a dynamic cross-linkable elastomer (JSR Corporation Exelin 1600N) 5% by weight were dry blended. This was supplied to a single-screw extruder having a barrel temperature of 180 to 220 ° C., extruded from a single-layer T die having a temperature of 230 ° C., cooled and solidified by a take-up roll having a set temperature of 60 ° C., and wound in an unstretched state. The thickness of the obtained film was 150 μm.

Example 14
A film was prepared in the same manner as in Example 13, except that 90% by weight of the hydrogenated styrene-butadiene block copolymer and 10% by weight of the dynamically crosslinked elastomer (Excellin 1600N) were used.

Example 15
A film was prepared in the same manner as in Example 13 except that 80% by weight of a styrene-butadiene block copolymer hydrogenated product and 20% by weight of a dynamically crosslinked elastomer (Excellin 1600N) were used.

Example 16
A film was prepared in the same manner as in Example 13 except that 70% by weight of hydrogenated styrene-butadiene block copolymer and 30% by weight of dynamically crosslinked elastomer (Excellin 1600N) were used.

Example 17
A resin obtained by dry blending 95% by weight of a styrene-butadiene block copolymer hydrogenated product (SEBS resin Asahi Kasei Chemicals Co., Ltd. Tuftec H1062) and 5% by weight of a dynamically crosslinked elastomer (Elastomer AR 9060 made by Aron Kasei Co., Ltd.) The resin for layer (A) was used.

  Ethylene resin (ethylene-methyl methacrylate copolymer Arkema Co., Ltd. Rotoryl 9MA02) 100% by weight was used as the resin for the layer (B).

  The above two types of resins are respectively supplied to different single screw extruders, co-extruded from a two-layer T die so as to be (A) / (B), and cooled and solidified by a take-up roll having a set temperature of 60 ° C. And wound up in an unstretched state. In addition, the barrel temperature of each extruder at this time was 180-220 degreeC, and the temperature of 2 layer T dice | dies was 230 degreeC.

  The total thickness of the obtained two-layer film was 180 μm, the layer (A) was 150 μm, and the layer (B) was 30 μm.

Example 18
A two-layer film was prepared in the same manner as in Example 17 except that 90% by weight of a styrene-butadiene block copolymer hydrogenated product and 10% by weight of a dynamically crosslinked elastomer (elastomer AR 9060) were used.

Example 19
A two-layer film was prepared in the same manner as in Example 17 except that 80% by weight of a styrene-butadiene block copolymer hydrogenated product and 20% by weight of a dynamically crosslinked elastomer (elastomer AR 9060) were used.

Example 20
A two-layer film was prepared in the same manner as in Example 17 except that 70% by weight of a styrene-butadiene block copolymer hydrogenated product and 30% by weight of a dynamically crosslinked elastomer (elastomer AR 9060) were used.

Test Example 1 (Evaluation method for cutting waste)
A part of the film obtained in the above examples and comparative examples is cut into a circular shape with a diameter of 180 mm to obtain a measurement sample, which is then set in a grinding machine (AUTOMATIC DICING SAW DAD-2H / 6 manufactured by DISCO Corporation). Then, the substrate film was cut under the following conditions, and then the sample was removed from the grinding device and dried at room temperature in a clean booth for 24 hours, and then using a digital microscope (VHX-100) manufactured by Keyence Corporation, The presence or absence of cutting waste was evaluated at a magnification of 100 times.

The surface of the sample was arbitrarily observed at 10 locations, and “◯” was given when there was no cutting waste, and “X” was given when it was recognized that there was even a small amount of cutting waste. The results are summarized in Table 1.
(Cutting conditions)
Rotation speed: 30000rpm
Speed: 80mm / sec
Cut mode: Full-auto dicing of 10mm □ Cut depth: 100μm
Blade: Disco B1A801 SDC 400N50M51 (outer diameter 56mm x thickness 0.2mm x inner diameter 40mm)
Water volume: 1.2L / min
Test Example 2 (Method for Measuring Average Particle Diameter and Area of Crosslinked Copolymer Rubber)
A sample having a size of 5 mm × 5 mm was cut out from 20 arbitrary points of the film obtained in the above Examples and Comparative Examples to obtain a measurement sample. The sample for measurement was set on a scanning probe microscope (Scanning Probe Microscope SPM-9600) manufactured by Shimadzu Corporation so that the thermoplastic elastomer composition layer would be the measurement surface, measured under the following conditions, and the average particle diameter of the crosslinked rubber and The area ratio occupied by the particles was determined. The same measurement was performed on the remaining 19 measurement samples, and the area ratio was determined.

An average value was determined from the area ratio of the 20 points thus obtained, and the value was used as a representative value for each example. The results are summarized in Table 1.
(Measurement condition)
Pre-processing: None Observation mode: Phase (resonance mode)
Observation field: 20 μm
Analysis Processing: Particle Analysis For example, a scanning probe micrograph of the film of Example 1 is shown in FIG. In FIG. 3, SEBS resin forms a sea phase, and crosslinked rubber particles form an island phase.

  As shown in Table 1, the film of the example was good because the area ratio of the crosslinked rubber was in a predetermined range and there was no cutting waste after dicing. On the other hand, in the comparative example, cutting waste was observed.

  FIGS. 1 and 2 show photographs obtained by dicing the films of Example 1 and Comparative Example 1 and then observing the cutting portion at the beginning of dicing using a digital microscope (VHX-100) manufactured by Keyence Corporation.

2 is an enlarged photograph of a film dicing start portion in Example 1. FIG. 2 is an enlarged photograph of a film dicing start portion in Comparative Example 1. FIG. 2 is a scanning probe photomicrograph of the film of Example 1. FIG.

Claims (9)

  A substrate film for dicing comprising a thermoplastic elastomer composition in which rubber particles crosslinked in a thermoplastic resin are finely dispersed.   The substrate film for dicing according to claim 1, wherein the average particle diameter of the crosslinked rubber particles is 0.1 to 50 µm.   The substrate film for dicing according to claim 1 or 2, wherein the average value of the ratio of the area of the crosslinked rubber particles to the area of the thermoplastic resin is 1 to 75%.   The thermoplastic elastomer composition is a crosslinked composition obtained by dynamically crosslinking a resin composition containing a thermoplastic resin, a crosslinkable copolymer rubber, and a softening agent in the presence of a crosslinking agent. 4. The substrate film for dicing according to any one of 3 above.   5. The substrate film for dicing according to claim 4, wherein the crosslinkable copolymer rubber is an olefin copolymer rubber or a styrene copolymer rubber.   The substrate film for dicing according to any one of claims 1 to 5, wherein the thermoplastic resin is a polyolefin resin and / or a polystyrene resin.   The dicing according to claim 6, wherein the polyolefin resin is at least one selected from the group consisting of branched low-density polyethylene, linear low-density polyethylene, high-density polyethylene, polypropylene, and propylene-α-olefin copolymer. Base film for use.   The polystyrene resin is at least one selected from the group consisting of a styrene homopolymer, a styrene-butyl acrylate copolymer, a styrene-conjugated diene block copolymer, and a hydrogenated styrene-conjugated diene block copolymer. The substrate film for dicing according to claim 6.   The dicing film which further has an adhesive layer in the base film for dicing in any one of Claims 1-8.

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