JP6703430B2 - Adhesive sheet for glass dicing and method for producing the same - Google Patents

Description

TECHNICAL FIELD The present invention relates to a pressure-sensitive adhesive sheet for glass dicing, which is used for dicing a glass plate to obtain a glass chip, and a method for producing the same.

Fine glass fragments are required to manufacture camera modules for mobile phones and smartphones. Such a glass piece can be obtained by dicing one glass plate using a dicing sheet. That is, after sticking a glass plate on a dicing sheet and then cutting the glass plate with a dicing blade, individualized glass (hereinafter sometimes referred to as “glass chip”) can be obtained. In recent years, as smartphones and the like have become thinner, and camera modules to be mounted have become smaller, it has become necessary to manufacture thinner and finer glass chips.

When dicing a brittle material such as glass, chipping easily occurs. Here, the chipping means that the end portion or the cut surface of the glass chip is chipped during dicing. The occurrence of chipping becomes more remarkable as the glass plate becomes thinner.

Further, the pressure-sensitive adhesive sheet for glass dicing is required not to cause a phenomenon in which the formed glass chips are peeled off from the pressure-sensitive adhesive sheet and scattered (hereinafter, may be referred to as “chip scattering”) during dicing. Be done.

Patent Document 1 discloses a pressure-sensitive adhesive sheet for glass substrate dicing in which a pressure-sensitive adhesive layer is provided on a base film. In this Patent Document 1, a film having a thickness of 130 μm or more and a tensile elastic modulus of 1 GPa or more is used as a base film, and the thickness of the pressure-sensitive adhesive layer is set to 9 μm or less. It is disclosed that the deformation can be reduced and the occurrence of chipping and chip scattering can be suppressed (paragraph 0010 of Patent Document 1).

Patent No. 3838637

By the way, in recent years, the size of the camera module has been reduced, and the size of the required glass chip has also become very small. The pressure-sensitive adhesive sheet disclosed in Patent Document 1 cannot sufficiently suppress chip scattering of such a glass chip having a very small size.

The present invention has been made in view of the above situation, and an object of the present invention is to provide a pressure-sensitive adhesive sheet for glass dicing in which chip scattering hardly occurs during dicing, and a method for manufacturing the same.

In order to achieve the above object, firstly, the present invention is a pressure-sensitive adhesive sheet for glass dicing, comprising: a base material; and a pressure-sensitive adhesive layer laminated on at least one surface of the base material. Provided is a pressure-sensitive adhesive sheet for glass dicing, which has a layer thickness of more than 9 μm and 40 μm or less (Invention 1).

In the above invention (Invention 1), since the pressure-sensitive adhesive layer has the above-mentioned thickness, the pressure-sensitive adhesive layer exhibits excellent tack, and the glass chip is favorably held on the pressure-sensitive adhesive sheet for glass dicing, resulting in dicing. At, chip scattering is suppressed.

In the said invention (invention 1), it is preferable that the said adhesive layer consists of an energy ray curable adhesive (invention 2).

In the above inventions (Inventions 1 and 2), the amount of energy in the pressure-sensitive adhesive layer measured with a probe tack under the condition that the peeling speed is changed to 1 mm/min in the method described in JIS Z0237: 1991 is 0. It is preferably 01 to 5 mJ/5 mmφ (Invention 3).

In the said invention (invention 1-3), it is preferable that the storage elastic modulus in 23 degreeC of the said adhesive layer is 30-100 kPa (invention 4).

In the above inventions (Inventions 1 to 4), the surface of the pressure-sensitive adhesive layer opposite to the substrate is attached to non-alkali glass, and the non-alkali of the pressure-sensitive adhesive sheet for glass dicing after standing for 20 minutes. The adhesive force to glass is preferably 5000 to 25000 mN/25 mm (Invention 5).

In the above invention (Invention 2), the surface of the pressure-sensitive adhesive layer opposite to the substrate is adhered to non-alkali glass, and the pressure-sensitive adhesive layer for glass dicing after irradiating the pressure-sensitive adhesive layer with energy rays. The adhesive strength of the sheet to the alkali-free glass is preferably 50 to 250 mN/25 mm (Invention 6).

In the above inventions (Inventions 1 to 6), the pressure-sensitive adhesive layer is formed from a pressure-sensitive adhesive composition containing a (meth)acrylic acid ester copolymer (A) having an energy ray-curable group introduced into a side chain. It is preferable that the pressure sensitive adhesive comprises an adhesive (Invention 7).

In the said invention (invention 7), it is preferable that the said adhesive composition further contains the energy ray-curable compound (B) other than the said (meth)acrylic acid ester copolymer (A) (invention 8).

In the above inventions (Inventions 1 to 6), the pressure-sensitive adhesive layer is an energy ray-curable resin other than an acrylic polymer (N) having no energy ray-curable property and the (meth)acrylic acid ester copolymer (A). It is preferable that the pressure-sensitive adhesive composition is formed of a pressure-sensitive adhesive composition containing the polymerizable compound (B) (Invention 9).

In the said invention (invention 7-9), it is preferable that the said adhesive composition further contains a crosslinking agent (C) (invention 10).

In the above invention (invention 1 to 10), a glass plate, it is preferable plane is for dicing glass tip having an area of ^{1 × 10 -6 mm 2 ~1mm 2} ( invention 11).

Secondly, the present invention relates to a method for producing the pressure-sensitive adhesive sheet for glass dicing (Inventions 7 and 8), which comprises at least a (meth)acrylic acid alkyl ester monomer (A1) and a functional group having a reactive functional group. Energy having an acrylic copolymer (AP) obtained by copolymerizing a monomer (A2), a functional group capable of reacting with the functional group of the functional group-containing monomer (A2), and an energy ray-curable carbon-carbon double bond. A step of reacting with a ray-curable group-containing compound (A3) to prepare a (meth)acrylic acid ester copolymer (A) having an energy ray-curable group introduced into a side chain, and the (meth)acrylic A method for producing a pressure-sensitive adhesive sheet for glass dicing, comprising the step of laminating a pressure-sensitive adhesive layer on at least one surface of a substrate using a pressure-sensitive adhesive composition containing an acid ester copolymer (A). (Invention 12).

In the above invention (Invention 12), the reaction between the acrylic copolymer (AP) and the energy ray-curable group-containing compound (A3) is performed by using an organic compound containing zirconium, an organic compound containing titanium and tin. It is preferable to carry out in the presence of at least one organic metal catalyst (D) selected from organic compounds containing (Invention 13).

According to the pressure-sensitive adhesive sheet for glass dicing according to the present invention and the pressure-sensitive adhesive sheet for glass dicing manufactured by the manufacturing method according to the present invention, chip scattering hardly occurs during dicing.

Hereinafter, embodiments of the present invention will be described.
The pressure-sensitive adhesive sheet for glass dicing according to the present embodiment (hereinafter, may be simply referred to as “pressure-sensitive adhesive sheet”) includes at least a base material and a pressure-sensitive adhesive layer laminated on one surface of the base material. It

In the pressure-sensitive adhesive sheet for glass dicing according to this embodiment, the thickness of the pressure-sensitive adhesive layer is more than 9 μm and 40 μm or less. Since the pressure-sensitive adhesive layer is relatively thick in this way, the pressure-sensitive adhesive layer can exhibit excellent tack. As a result, even when the formed glass chip is subjected to the impact of dicing, it is favorably held on the adhesive sheet, and as a result, chip scattering is suppressed during dicing.

1. Base Material The base material of the pressure-sensitive adhesive sheet for glass dicing according to the present embodiment is not particularly limited in its constituent material as long as it exhibits a desired function in the step of using the pressure-sensitive adhesive sheet. The base material may include a film (resin film) containing a resin-based material as a main material. Preferably, the base material consists of a resin film only. Specific examples of the resin film include ethylene-vinyl acetate copolymer films, ethylene-(meth)acrylic acid copolymer films, ethylene-(meth)acrylic acid ester copolymer films, and other ethylene-based copolymer films; polyethylene. Polyolefin films such as films, polypropylene films, polybutene films, polybutadiene films, polymethylpentene films, ethylene-norbornene copolymer films, norbornene resin films; polyvinyl chloride films such as polyvinyl chloride films and vinyl chloride copolymer films Examples of the film include polyester films such as polyethylene terephthalate film and polybutylene terephthalate film; polyurethane films; polyimide films; polystyrene films; polycarbonate films; fluororesin films. Examples of the polyethylene film include a low density polyethylene (LDPE) film, a linear low density polyethylene (LLDPE) film, a high density polyethylene (HDPE) film and the like. In addition, modified films such as crosslinked films and ionomer films are also used. The substrate may be a film made of one of these, or may be a laminated film in which two or more of these are combined. Among these, it is preferable to use a polyethylene terephthalate film from the viewpoint of easily achieving the storage elastic modulus described later. In addition, in this specification, "(meth)acrylic acid" means both acrylic acid and methacrylic acid. The same applies to other similar terms.

In the base material, various additives such as pigments, dyes, flame retardants, plasticizers, antistatic agents, lubricants and fillers may be contained in the film. Examples of pigments include titanium dioxide and carbon black. Examples of the filler include organic materials such as melamine resin, inorganic materials such as fumed silica, and metal materials such as nickel particles. Although the content of these additives is not particularly limited, it is preferably within a range in which the substrate exhibits desired functions and does not lose smoothness and flexibility.

When ultraviolet rays are used as the energy rays for irradiating to cure the pressure-sensitive adhesive layer, it is preferable that the substrate has transparency to ultraviolet rays. Further, when an electron beam is used as the energy beam, it is preferable that the base material be transparent to the electron beam.

The surface of the base material on the pressure-sensitive adhesive layer side may be subjected to a surface treatment such as a primer treatment, a corona treatment, a plasma treatment, and a surface roughening treatment (matting treatment) in order to enhance the adhesion to the pressure-sensitive adhesive layer. .. Examples of the surface-roughening treatment include an embossing method and a sandblasting method. Further, various coating films may be provided on the surface of the base material opposite to the pressure-sensitive adhesive layer.

In the pressure-sensitive adhesive sheet for glass dicing according to this embodiment, the storage elastic modulus of the base material at 23° C. is preferably 100 to 8000 MPa, particularly preferably 1500 to 7000 MPa, and further preferably 2000 to 6000 MPa. Is preferred. When the storage elastic modulus of the base material at 23° C. is 100 MPa or more, occurrence of shaking of the pressure-sensitive adhesive sheet in the dicing process is reduced, movement of the glass plate on the pressure-sensitive adhesive sheet is suppressed, and chipping and die shift are prevented. Can be suppressed. Note that the die shift means that the glass plate is displaced from its original position on the adhesive sheet during dicing. If the dicing is further advanced in the state where the die shift has occurred, the glass plate cannot be cut at the intended position, and as a result, the glass chip having the desired shape cannot be obtained. Moreover, when the storage elastic modulus of the base material at 23° C. is 8000 MPa or less, the pressure-sensitive adhesive sheet has an appropriate elastic modulus, and the glass chip after dicing can be picked up well. The storage elastic modulus at 23° C. of the base material was measured under the following conditions using a dynamic elastic modulus measuring device (manufactured by TA Instruments, product name “DMA Q800”). is there.
Test start temperature: 0℃
Test end temperature: 200℃
Temperature rising rate: 3°C/min Frequency: 11Hz
Amplitude: 20 μm

The thickness of the substrate is not limited as long as it can properly function in the step in which the pressure-sensitive adhesive sheet is used, but it is usually preferably 20 to 450 μm, particularly preferably 25 to 300 μm, and further 50 to 200 μm. Is preferred. When the thickness of the base material is 20 μm or more, the occurrence of breakage when handling the pressure-sensitive adhesive sheet is suppressed, and good handleability can be obtained. Further, the occurrence of shaking of the pressure-sensitive adhesive sheet in the dicing process is reduced, the movement of the glass plate on the pressure-sensitive adhesive sheet is suppressed, and the occurrence of chipping and die shift can be suppressed. On the other hand, when the thickness of the base material is 450 μm or less, the manufacturing cost can be suppressed. In addition, the pressure-sensitive adhesive sheet can be easily wound into a roll, and curling can be easily eliminated during use. That is, good handling properties can be obtained during production and use. Further, the base material is easily deformed according to the operation of the pickup, and it becomes possible to pick up without requiring excessive force. Therefore, the pickup process can be efficiently performed.

The thickness of the base material is preferably less than 130 μm from the viewpoints of further suppressing the manufacturing cost and obtaining more excellent handling properties. Specifically, it is preferably 50 μm or more and less than 130 μm, particularly preferably 70 μm or more and 120 μm or less, and further preferably 80 μm or more and 110 μm or less.

2. Pressure-sensitive adhesive layer (1) Thickness and physical properties of pressure-sensitive adhesive layer In the pressure-sensitive adhesive sheet for glass dicing according to this embodiment, the pressure-sensitive adhesive layer has a thickness of more than 9 μm and 40 μm or less, and more than 9 μm and 30 μm or less. Is preferred, and particularly preferably more than 9 μm and 20 μm or less. When the thickness of the pressure-sensitive adhesive layer is 9 μm or less, tack of the pressure-sensitive adhesive layer becomes insufficient, the glass chip cannot be sufficiently held on the pressure-sensitive adhesive sheet during dicing, and as a result, chip scattering can be prevented. Can not. If the thickness of the pressure-sensitive adhesive layer exceeds 40 μm, the pressure-sensitive adhesive layer is likely to shake during dicing, and as a result, chipping and die shift are likely to occur.

The amount of energy in the pressure-sensitive adhesive layer measured using probe tack (also referred to as “tack value” in this specification) is preferably 0.01 to 5 mJ/5 mmφ, and particularly 0.13 to 4 mJ/5 mmφ. Is more preferable, and 0.18 to 3.5 mJ/5 mmφ is more preferable. When the tack value is within the above range, it is possible to effectively suppress chip scattering during dicing. In addition, in this specification, when the pressure-sensitive adhesive layer is composed of an energy ray-curable pressure-sensitive adhesive described later, the tack value is a value measured before the energy ray irradiation. In addition, the tack value in the present specification is measured by the method described in JIS Z0237:2009 under the condition that the peeling speed is changed to 1 mm/min, and the details are as shown in the test examples described later.

The storage elastic modulus of the pressure-sensitive adhesive layer at 23° C. is preferably 30 to 100 kPa, particularly preferably 40 to 90 kPa, and further preferably 50 to 80 kPa. When the storage elastic modulus is in the above range, the pressure-sensitive adhesive sheet for glass dicing can exhibit good pressure-sensitive adhesive force, whereby the glass chip is satisfactorily held on the pressure-sensitive adhesive sheet, and chip scattering during dicing is effective. Can be suppressed to. In the present specification, when the pressure-sensitive adhesive layer is composed of an energy ray-curable pressure-sensitive adhesive described later, the storage elastic modulus is a value measured before the energy ray irradiation. The method for measuring the storage elastic modulus of the pressure-sensitive adhesive layer at 23° C. before irradiation with energy rays is as shown in Test Examples described later.

The storage elastic modulus at 100° C. of the pressure-sensitive adhesive layer is preferably 5 to 50 kPa, particularly preferably 7 to 40 kPa, and further preferably 10 to 30 kPa. Generally, in a pressure-sensitive adhesive sheet for glass dicing, frictional heat is generated during dicing, and the pressure-sensitive adhesive layer is in a high temperature state of about 100°C. Even in such a high temperature state, since the pressure-sensitive adhesive layer exhibits a storage elastic modulus of 5 kPa or more, occurrence of shaking during dicing is suppressed, and movement of the glass plate on the pressure-sensitive adhesive sheet is suppressed, resulting in chipping and Die shift is less likely to occur. Further, when the storage elastic modulus is 50 kPa or less, the elastic modulus of the pressure-sensitive adhesive layer does not become extremely high, and good adhesiveness can be obtained, and as a result, chip scattering during dicing is effectively suppressed. can do. In the present specification, when the pressure-sensitive adhesive layer is composed of an energy ray-curable pressure-sensitive adhesive described later, the storage elastic modulus is a value measured before the energy ray irradiation. The method for measuring the storage elastic modulus of the pressure-sensitive adhesive layer at 100° C. before irradiation with energy rays is as shown in the test example described later.

When the pressure-sensitive adhesive layer is composed of an energy ray-curable pressure-sensitive adhesive described below, the tensile elastic modulus at 23° C. of the pressure-sensitive adhesive layer after irradiation with energy rays is preferably 20 to 100 MPa, and particularly 25 to 90 MPa. Is preferable, and more preferably 25 to 85 MPa. When the tensile elastic modulus is 20 MPa or more, it is possible to favorably pick up the glass chip after irradiation with energy rays. Further, when the tensile elastic modulus is 100 MPa or less, the adhesive strength of the pressure-sensitive adhesive sheet for glass dicing is suppressed from being excessively reduced, and when the energy ray irradiation is performed before the expansion, the chips are separated during the expansion. Can be effectively suppressed. The method for measuring the tensile modulus of elasticity of the pressure-sensitive adhesive layer at 23° C. before irradiation with energy rays is as shown in the test example described later.

The gel fraction of the pressure-sensitive adhesive forming the pressure-sensitive adhesive layer is preferably 12.5 to 100%, particularly preferably 37.5 to 100%, and further preferably 50 to 95%. .. When the gel fraction of the pressure-sensitive adhesive is within the above range, it becomes easy to satisfy the above-mentioned physical properties of the pressure-sensitive adhesive layer. Moreover, when the gel fraction of the pressure-sensitive adhesive is 12.5% or more, the cohesive force of the pressure-sensitive adhesive becomes good, and the durability of the pressure-sensitive adhesive layer is maintained.

(2) Adhesive that constitutes the adhesive layer The adhesive that constitutes the adhesive layer may be a non-curable adhesive or a curable adhesive. The curable pressure-sensitive adhesive may be in a pre-cured state or a post-cured state. When the pressure-sensitive adhesive layer is composed of multiple layers, it may be a combination of a non-curable pressure-sensitive adhesive and a curable pressure-sensitive adhesive. Examples of non-curable adhesives include acrylic adhesives, rubber adhesives, silicone adhesives, urethane adhesives, polyester adhesives, polyvinyl ether adhesives, and the like. Examples of curable pressure-sensitive adhesives include energy ray-curable pressure-sensitive adhesives and thermosetting pressure-sensitive adhesives.

In the pressure-sensitive adhesive sheet for glass dicing according to this embodiment, the pressure-sensitive adhesive layer is preferably made of an energy ray-curable pressure-sensitive adhesive, and particularly preferably an energy ray-curable acrylic pressure-sensitive adhesive. When the pressure-sensitive adhesive layer is made of an energy ray-curable pressure-sensitive adhesive, it becomes possible to irradiate the pressure-sensitive adhesive layer with energy rays before the pickup step to cure the pressure-sensitive adhesive. As a result, the adhesive force of the adhesive sheet with respect to the glass chip is appropriately reduced, and the pickup can be favorably performed.

Generally, the energy ray-curable acrylic pressure-sensitive adhesive contains a (meth)acrylic acid ester copolymer (A) having an energy ray-curable group introduced into its side chain, Those formed from a pressure-sensitive adhesive composition containing no energy ray-curable compound (B) other than the ester copolymer (A) (hereinafter sometimes referred to as "X type" for convenience), and energy ray-curing. Formed from a pressure-sensitive adhesive composition containing an energy ray-curable compound (B) other than the acrylic polymer (N) having no property and the (meth)acrylic acid ester copolymer (A) (hereinafter, For convenience, it may be referred to as "Y type"), and a (meth)acrylic acid ester copolymer (A) having an energy ray-curable group introduced into its side chain and the (meth)acrylic acid ester copolymer. There are those formed from a pressure-sensitive adhesive composition containing an energy ray-curable compound (B) other than (A) (hereinafter sometimes referred to as “Z type” for convenience).

In the pressure-sensitive adhesive sheet for glass dicing according to this embodiment, the pressure-sensitive adhesive layer may be made of any of these types of pressure-sensitive adhesives. In particular, since a Y type adhesive easily obtains excellent tack, it is preferable to use a Y type adhesive from the viewpoint of effectively suppressing chip scattering during dicing. Further, since the X type adhesive has a higher elastic modulus in a high temperature state, it is preferable to use the X type adhesive from the viewpoint of suppressing chipping and die shift. Furthermore, when a Z type adhesive is used, the elastic modulus of the adhesive layer after irradiation with energy rays becomes higher. Therefore, from the viewpoint of good pickup, it is preferable to use a Z type adhesive.

The above-mentioned (meth)acrylic acid ester copolymer (A) having an energy ray-curable group introduced into the side chain and the acrylic polymer (N) having no energy ray-curability are contained in the pressure-sensitive adhesive layer as they are. Or may be contained as a crosslinked product by performing a crosslinking reaction with a crosslinking agent (C) described later.

(2-1) (Meth)acrylic acid ester copolymer (A) having an energy ray-curable group introduced into its side chain
The (meth)acrylic acid ester copolymer (A) having an energy ray-curable group introduced into the side chain is obtained by reacting the acrylic copolymer (AP) with the energy ray-curable group-containing compound (A3). It is preferably obtained by

The acrylic copolymer (AP) is preferably a copolymer of at least a (meth)acrylic acid alkyl ester monomer (A1) and a functional group-containing monomer (A2) having a reactive functional group.

The (meth)acrylic acid alkyl ester monomer (A1) preferably has an alkyl group with 1 to 18 carbon atoms, and particularly preferably has 1 to 4 carbon atoms. Specific examples of the (meth)acrylic acid alkyl ester monomer (A1) include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, n-butyl (meth)acrylate, and (meth). N-Pentyl acrylate, n-hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, n-decyl (meth)acrylate, lauryl (meth)acrylate, (meth) Examples include myristyl acrylate, palmityl (meth)acrylate, stearyl (meth)acrylate, and the like. These may be used alone or in combination of two or more.

The mass ratio of the structural portion derived from the (meth)acrylic acid alkyl ester monomer (A1) in the total mass of the acrylic copolymer (AP) is preferably 50 to 98 mass %, and particularly 60 to 95. It is preferably mass%, and more preferably 70 to 90 mass%.

As the functional group-containing monomer (A2), one having a reactive functional group capable of reacting with the functional group of the energy ray-curable group-containing compound (A3) is used. Examples of the functional group contained in the functional group-containing monomer (A2) include a hydroxyl group, a carboxy group, an amino group, a substituted amino group, and an epoxy group. Among them, a hydroxyl group and a carboxy group are preferable, and a hydroxyl group is particularly preferable. In addition, when using the crosslinking agent (C) mentioned later, the reactive functional group which the functional group containing monomer (A2) has may react with the said crosslinking agent (C).

When a monomer having a hydroxyl group (hydroxyl group-containing monomer) is used as the functional group-containing monomer (A2), examples thereof include (meth)acrylic acid hydroxyalkyl ester, and specific examples thereof include (meth)acrylic acid 2 -Hydroxyethyl, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, (meth)acrylic acid 4 -Hydroxybutyl and the like can be mentioned. Among these, 2-hydroxyethyl (meth)acrylate is preferable from the viewpoint of reactivity of hydroxyl group and copolymerizability. These may be used alone or in combination of two or more.

When a monomer having a carboxy group (carboxy group-containing monomer) is used as the functional group-containing monomer (A2), examples thereof include ethylenically unsaturated carboxylic acid, and specific examples thereof include acrylic acid, methacrylic acid, Examples thereof include crotonic acid, maleic acid, itaconic acid, citraconic acid and the like. Among these, acrylic acid is preferable from the viewpoint of reactivity of the carboxy group and copolymerizability. These may be used alone or in combination of two or more.

Note that different types of functional group-containing monomers (A2) may be used in combination. For example, the above-mentioned hydroxyl group-containing monomer and carboxy group-containing monomer may be used in combination.

The mass ratio of the functional group-containing monomer (A2)-derived structural portion to the total mass of the acrylic copolymer (AP) is preferably 5 to 40% by mass, and particularly 7 to 35% by mass. Is preferable, and more preferably 10 to 30% by mass. Energy to the (meth)acrylic acid ester copolymer (A) in which the energy ray-curable group is introduced into the side chain is set because the mass ratio of the structural portion derived from the functional group-containing monomer (A2) is within the above range. The introduction amount of the linear curable group-containing compound (A3) can be set within a suitable range. When the functional group-containing monomer (A2) and the cross-linking agent (C) are reacted with each other using the cross-linking agent (C) described below, the degree of cross-linking by the cross-linking agent (C), that is, the gel fraction. Can be adjusted to a suitable range, and physical properties such as cohesive force of the pressure-sensitive adhesive layer can be controlled.

The acrylic copolymer (AP) may contain other monomers as a monomer constituting the acrylic copolymer, in addition to the above-mentioned (meth)acrylic acid alkyl ester monomer (A1) and the functional group-containing monomer (A2).

Examples of the other monomer include an alkoxyalkyl group-containing (meth)acryl such as methoxymethyl (meth)acrylate, methoxyethyl (meth)acrylate, ethoxymethyl (meth)acrylate, and ethoxyethyl (meth)acrylate. Acid ester; (meth)acrylic acid ester having an aliphatic ring such as cyclohexyl (meth)acrylate; (meth)acrylic acid ester having an aromatic ring such as phenyl (meth)acrylate; Crosslinkable acrylamide; (meth)acrylic acid ester having non-crosslinkable tertiary amino group such as N,N-dimethylaminoethyl (meth)acrylate and N,N-dimethylaminopropyl (meth)acrylate; acetic acid Vinyl; styrene and the like can be mentioned. These may be used alone or in combination of two or more.

The acrylic copolymer (AP) may be polymerized in either a random copolymer or a block copolymer. The polymerization method is not particularly limited, and the polymerization can be performed by a general polymerization method.

The energy ray-curable group-containing compound (A3) has a functional group capable of reacting with the functional group of the functional group-containing monomer (A2), and an energy ray-curable carbon-carbon double bond.

Examples of the functional group capable of reacting with the functional group of the functional group-containing monomer (A2) include an isocyanate group and an epoxy group, and among them, an isocyanate group having high reactivity with a hydroxyl group is preferable.

As the curable group having an energy ray curable carbon-carbon double bond (energy ray curable group), a (meth)acryloyl group or the like is preferable. The energy ray-curable carbon-carbon double bond is preferably present in one molecule of the energy ray-curable group-containing compound (A3) in an amount of 1 to 5, particularly preferably 1 to 3.

Examples of the energy ray-curable group-containing compound (A3) include 2-methacryloyloxyethyl isocyanate, meta-isopropenyl-α,α-dimethylbenzyl isocyanate, methacryloyl isocyanate, allyl isocyanate, 1,1-(bisacryloyloxymethyl). ) Ethyl isocyanate; Acryloyl monoisocyanate compound obtained by reacting diisocyanate compound or polyisocyanate compound with hydroxyethyl (meth)acrylate; Reaction of diisocyanate compound or polyisocyanate compound, polyol compound, and hydroxyethyl (meth)acrylate And an acryloyl monoisocyanate compound obtained by the above. Among these, 2-methacryloyloxyethyl isocyanate is particularly preferable. The energy ray-curable group-containing compound (A3) may be used alone or in combination of two or more kinds.

In preparing the (meth)acrylic acid ester copolymer (A) having an energy ray-curable group introduced into its side chain, the preparation of the acrylic copolymer (AP) and the acrylic copolymer (AP) The reaction between the compound and the energy ray-curable group-containing compound (A3) can be carried out by a conventional method. In this reaction step, the reactive functional group derived from the functional group-containing monomer (A2) in the acrylic copolymer (AP) reacts with the functional group in the energy ray-curable group-containing compound (A3). To do. As a result, a (meth)acrylic acid ester copolymer (A) having an energy ray-curable group introduced into its side chain is obtained. In addition, as described later, the reaction between the acrylic copolymer (AP) and the energy ray-curable group-containing compound (A3) is preferably carried out in the presence of the organometallic catalyst (D).

In the (meth)acrylic acid ester copolymer (A) in which an energy ray-curable group is introduced into the side chain, the energy ray-curable group is contained with respect to the amount of the reactive functional group of the functional group-containing monomer (A2). The amount of the compound (A3) is preferably 30 to 100 mol %, particularly preferably 40 to 95 mol %, and further preferably 50 to 90 mol %.

The weight average molecular weight (Mw) of the (meth)acrylic acid ester copolymer (A) having an energy ray-curable group introduced into its side chain is preferably 100,000 to 2,500,000, and particularly 150,000 to 2,000,000. Is more preferable, and more preferably 300,000 to 1,500,000. In addition, the weight average molecular weight in this specification is the value of standard polystyrene conversion measured by the gel permeation chromatography (GPC) method. When the weight average molecular weight (Mw) of the (meth)acrylic acid ester copolymer (A) having an energy ray-curable group introduced into its side chain is within the above range, the coatability of the pressure-sensitive adhesive composition is ensured. At the same time, the cohesiveness of the pressure-sensitive adhesive layer becomes good, and thus physical properties suitable for dicing can be obtained.

(2-2) Acrylic polymer (N) having no energy ray curability
As the acrylic polymer (N) having no energy ray curability, a conventionally known acrylic polymer can be used as long as it has no energy ray curability. The acrylic polymer may be a homopolymer formed from one type of acrylic monomer, a copolymer formed from a plurality of types of acrylic monomers, or one type or It may be a copolymer formed from plural kinds of acrylic monomers and monomers other than acrylic monomers.

The specific type of the compound that becomes the acrylic monomer is not particularly limited, and specific examples thereof include (meth)acrylic acid, (meth)acrylic acid ester, and their derivatives (acrylonitrile, itaconic acid, etc.). More specific examples include the above-mentioned (meth)acrylic acid alkyl ester monomer (A1) and functional group-containing monomer (A2), and in addition, methoxymethyl (meth)acrylate and methoxy (meth)acrylate. Alkoxyalkyl group-containing (meth)acrylic acid esters such as ethyl, ethoxymethyl (meth)acrylate, ethoxyethyl (meth)acrylate; and (meth)acrylic acid esters having an aliphatic ring such as cyclohexyl (meth)acrylate; (Meth)acrylic acid ester having an aromatic ring such as phenyl (meth)acrylate; non-crosslinkable acrylamide such as acrylamide and methacrylamide; N,N-dimethylaminoethyl (meth)acrylate, (meth)acrylic acid (Meth)acrylic acid ester having a non-crosslinkable tertiary amino group such as N,N-dimethylaminopropyl; vinyl acetate; styrene and the like.

When the non-energy ray curable acrylic pressure-sensitive adhesive (N) has a reactive functional group derived from the functional group-containing monomer (A2), the acrylic polymer is used from the viewpoint of keeping the degree of crosslinking within a good range. The proportion of the mass of the structural portion derived from the functional group-containing monomer (A2) in the total mass is preferably about 1 to 20 mass %, more preferably 2 to 10 mass %.

The weight average molecular weight (Mw) of the acrylic polymer (N) having no energy ray curability is preferably 100,000 to 2,500,000, particularly preferably 150,000 to 2,000,000, and further 200,000. It is preferably ˜1.5 million. When the weight average molecular weight (Mw) of the acrylic polymer (N) having no energy ray curability is within the above range, the coatability of the pressure-sensitive adhesive composition is secured and the cohesiveness of the pressure-sensitive adhesive layer is ensured. Is favorable, physical properties suitable for dicing can be obtained.

(2-3) Energy ray curable compound (B)
The energy ray-curable compound (B) is a compound that polymerizes and cures when irradiated with energy rays such as ultraviolet rays and electron rays. Examples of the energy ray-curable compound (B) include low molecular weight compounds having an energy ray-polymerizable group (monofunctional or polyfunctional monomers and oligomers), specifically, trimethylolpropane triacrylate, Tetramethylolmethane tetraacrylate, pentaerythritol triacrylate, dipentaerythritol monohydroxypentaacrylate, dipentaerythritol hexaacrylate, 1,4-butylene glycol diacrylate, 1,6-hexanediol diacrylate and other acrylates, dicyclopentadiene dimethoxy Acrylate compounds such as acrylates containing a cycloaliphatic skeleton such as diacrylate and isobornyl acrylate, polyethylene glycol diacrylate, oligoester acrylate, urethane acrylate oligomer, epoxy modified acrylate, polyether acrylate and itaconic acid oligomer are used. Such a compound has an energy ray-curable double bond in the molecule, and usually has a molecular weight of 100 to 30,000, preferably about 300 to 10,000.

When the pressure-sensitive adhesive layer in the present embodiment is composed of the above-mentioned Y-type pressure-sensitive adhesive, the content of the energy ray-curable compound (B) in the pressure-sensitive adhesive composition is such that the energy ray-curable acrylic polymer ( N) With respect to 100 parts by mass, it is preferably 20 to 200 parts by mass, particularly preferably 40 to 160 parts by mass, and further preferably 40 to 150 parts by mass.

When the pressure-sensitive adhesive layer in the present embodiment is composed of the Z type pressure-sensitive adhesive described above, the content of the energy ray-curable compound (B) in the pressure-sensitive adhesive composition is such that an energy ray-curable group is introduced into the side chain. It is preferably 3 to 60 parts by mass, particularly preferably 5 to 50 parts by mass, and further 10 to 40 parts by mass with respect to 100 parts by mass of the (meth)acrylic acid ester copolymer (A). Preferably.

(3) Crosslinking agent (C)
The pressure-sensitive adhesive composition forming the pressure-sensitive adhesive layer in the present embodiment is a (meth)acrylic acid ester copolymer (A) having an energy ray-curable group introduced into a side chain or an acrylic resin having no energy ray-curability. It is preferable to contain a crosslinking agent (C) capable of crosslinking the polymer (N). In this case, the pressure-sensitive adhesive layer in the present embodiment is a cross-linked product obtained by a cross-linking reaction between the (meth)acrylic acid ester copolymer (A) or the acrylic polymer (N) and the cross-linking agent (C). Contains. By using such a cross-linking agent (C), it becomes easy to adjust the gel fraction of the pressure-sensitive adhesive forming the pressure-sensitive adhesive layer to a suitable range, and physical properties suitable for dicing can be obtained.

Examples of the type of the crosslinking agent (C) include epoxy compounds, polyisocyanate compounds, metal chelate compounds, polyimine compounds such as aziridine compounds, melamine resins, urea resins, dialdehydes, methylol polymers, metal alkoxides. , Metal salts and the like. Among these, an epoxy compound or a polyisocyanate compound is preferably used, and a polyisocyanate compound is particularly preferably used, because the crosslinking reaction is easily controlled.

Examples of the epoxy compound include 1,3-bis(N,N'-diglycidylaminomethyl)cyclohexane, N,N,N',N'-tetraglycidyl-m-xylylenediamine, ethylene glycol diglycidyl ether. , 1,6-hexanediol diglycidyl ether, trimethylolpropane diglycidyl ether, diglycidyl aniline, diglycidyl amine and the like.

The polyisocyanate compound is a compound having two or more isocyanate groups per molecule. Specific examples thereof include aromatic polyisocyanates such as tolylene diisocyanate, diphenylmethane diisocyanate, and xylylene diisocyanate; aliphatic polyisocyanates such as hexamethylene diisocyanate; alicyclic polyisocyanates such as isophorone diisocyanate and hydrogenated diphenylmethane diisocyanate. .. Furthermore, these biuret bodies, isocyanurate bodies, adduct bodies and the like can be mentioned. Examples of the adduct include a reaction product with a low molecular weight active hydrogen-containing compound such as ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane and castor oil.

As the crosslinking agent (C), one type may be used alone, or two or more types may be used in combination.

When the pressure-sensitive adhesive is of X type or Z type, the content of the cross-linking agent (C) in the pressure-sensitive adhesive composition forming the pressure-sensitive adhesive layer is (meth)acrylic acid having an energy ray-curable group introduced into its side chain. It is preferably 0.01 to 15 parts by mass, particularly preferably 0.05 to 10 parts by mass, and further preferably 0.1 to 2 parts by mass with respect to 100 parts by mass of the ester copolymer (A). Preferably. When the pressure-sensitive adhesive is of the Y type, the content of the crosslinking agent (C) in the pressure-sensitive adhesive composition forming the pressure-sensitive adhesive layer is 3 with respect to the acrylic polymer (N) having no energy ray curability. It is preferably ˜20 parts by mass, particularly preferably 5 to 17 parts by mass, further preferably 7-14 to 14 parts by mass.

(4) Organometallic catalyst (D)
In order to obtain a (meth)acrylic acid ester copolymer (A) in which an energy ray-curable group is introduced into a side chain, an acrylic copolymer (AP) and an energy ray-curable group-containing compound (A3) are combined. When the reaction is carried out, the reaction is preferably carried out in the presence of the organometallic catalyst (D). As the organometallic catalyst (D), it is particularly preferable to use at least one selected from an organic compound containing zirconium, an organic compound containing titanium, and an organic compound containing tin. The pressure-sensitive adhesive composition containing the (meth)acrylic acid ester copolymer (A) obtained by reacting in the presence of such an organometallic catalyst (D) has a more excellent tack. A layer can be formed, and chip scattering can be effectively suppressed during dicing. Among the above three kinds of organic compounds, the organometallic catalyst (D) is preferably at least one of an organic compound containing zirconium and an organic compound containing titanium, and particularly preferably an organic compound containing zirconium. Is preferred.

Examples of the form of the organic compound include an alkoxide compound, a chelate compound, an acylate compound and the like, and among these, the chelate compound is preferable.

Specific examples of the organometallic catalyst (D) include zirconium alkoxide, zirconium chelate, titanium alkoxide, titanium chelate, tin alkoxide and tin chelate. Of these, zirconium chelate is preferable. The organometallic catalyst (D) may be composed of one kind of these compounds, or may be composed of two or more kinds of these compounds.

The amount of the organometallic catalyst (D) used in the reaction for obtaining the (meth)acrylic acid ester copolymer (A) having an energy ray-curable group introduced into the side chain is not limited. The amount used is preferably 0.001 to 10 parts by mass, particularly 0.01 to 10 parts by mass, based on 100 parts by mass of the solid content of the (meth)acrylic acid ester copolymer (A). The amount is preferably 5 parts by mass, more preferably 0.05 to 3 parts by mass. In the present invention, the term “metal amount conversion” means a blending amount or a blending ratio calculated by the weight of the metal alone, excluding the weight corresponding to the molecular weight of the structure composed of an organic substance in the organometallic catalyst (D). Say.

(5) Other components The pressure-sensitive adhesive composition that forms the pressure-sensitive adhesive layer in the present embodiment includes, in addition to the above components, a photopolymerization initiator, a crosslinking accelerator, a coloring material such as a dye or a pigment, a flame retardant, and a filler. , And various additives such as antistatic agents may be contained.

Examples of the photopolymerization initiator include photoinitiators such as benzoin compounds, acetophenone compounds, acylphosphine oxide compounds, titanocene compounds, thioxanthone compounds and peroxide compounds, and photosensitizers such as amines and quinones. Specifically, α-hydroxycyclohexyl phenyl ketone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzyl diphenyl sulfide, tetramethyl thiuram monosulfide, azobisisobutyronitrile, dibenzyl, diacetyl, β-chlore. Examples thereof include anthraquinone and 2,4,6-trimethylbenzoyldiphenylphosphine oxide. When ultraviolet rays are used as energy rays, the irradiation time and irradiation amount can be shortened by incorporating a photopolymerization initiator.

When the pressure-sensitive adhesive composition forming the pressure-sensitive adhesive layer in the present embodiment contains the crosslinking agent (C), a suitable crosslinking accelerator may be contained depending on the type of the crosslinking agent (C) and the like.

(6) Irradiation with energy rays In the pressure-sensitive adhesive sheet for glass dicing according to the present embodiment, when the pressure-sensitive adhesive layer is made of an energy ray-curable pressure-sensitive adhesive, the energy rays for curing the pressure-sensitive adhesive are ionizing radiation. That is, examples thereof include ultraviolet rays, electron beams, and X-rays. Among these, ultraviolet rays, which are relatively easy to introduce irradiation equipment, are preferable.

When ultraviolet rays are used as the ionizing radiation, it is preferable to use near ultraviolet rays including ultraviolet rays having a wavelength of about 200 to 380 nm for easy handling. The amount of light may be appropriately selected according to the type of energy ray-curable component contained in the pressure-sensitive adhesive composition and the thickness of the pressure-sensitive adhesive layer, and is usually about 50 to 500 mJ/cm ² , and 100 to 450 mJ/ cm ² is preferable, and 200 to 400 mJ/cm ² is more preferable. The ultraviolet illumination is usually 50 to 500 mW / cm ² or so, preferably from ^{100~450mW / cm 2, 200~400mW / cm} 2 is more preferable. The ultraviolet source is not particularly limited, and for example, a high pressure mercury lamp, a metal halide lamp, a UV-LED, etc. can be used.

When an electron beam is used as the ionizing radiation, the accelerating voltage may be appropriately selected according to the type of energy ray-curable component contained in the pressure-sensitive adhesive composition and the thickness of the pressure-sensitive adhesive layer. The voltage is preferably about 10 to 1000 kV. The irradiation dose may be set in a range in which the pressure-sensitive adhesive is appropriately cured, and is usually selected in the range of 10 to 1000 krad. The electron beam source is not particularly limited, and for example, various electron beam accelerators such as Cockloft-Walton type, Van de Graft type, resonance transformer type, insulating core transformer type, linear type, dynamitron type, high frequency type, etc. are used. be able to.

3. Release film In the pressure-sensitive adhesive sheet for glass dicing according to this embodiment, a release film is laminated on the surface of the pressure-sensitive adhesive layer for the purpose of protecting the surface on the side opposite to the base material until the adherend is attached. May be. The structure of the release film is arbitrary, and examples include those obtained by subjecting a plastic film to release treatment with a release agent or the like. Specific examples of the plastic film include polyester films such as polyethylene terephthalate, polybutylene terephthalate and polyethylene naphthalate, and polyolefin films such as polypropylene and polyethylene. As the release agent, a silicone release agent, a fluorine release agent, a long chain alkyl release agent, or the like can be used. Of these, a silicone-based release agent that is inexpensive and that provides stable performance is preferable. The thickness of the release film is not particularly limited, but is usually about 20 to 250 μm.

4. Physical Properties of Pressure-Sensitive Adhesive Sheet for Glass Dicing The surface of the pressure-sensitive adhesive layer opposite to the substrate is attached to non-alkali glass, and the non-alkali glass of the pressure-sensitive adhesive sheet for glass dicing according to the present embodiment after standing for 20 minutes The adhesive strength to is preferably 5000 to 25000 mN/25 mm, particularly preferably 9000 to 22000 mN/25 mm, and further preferably 9500 to 18000 mN/25 mm. When the adhesive strength is within the above range, the glass chip can be favorably held on the adhesive sheet during dicing. As a result, chip scattering during dicing is effectively suppressed. Further, since the glass plate and the glass chips are favorably held on the adhesive sheet during dicing, the deviation of the glass plate and the glass chips on the adhesive sheet is suppressed, and die shift and chipping hardly occur. In the present specification, when the pressure-sensitive adhesive layer is composed of the energy ray-curable pressure-sensitive adhesive described above, the pressure-sensitive adhesive force is a value measured before irradiation with energy rays.

When the pressure-sensitive adhesive layer is composed of the energy ray-curable pressure-sensitive adhesive described above, after the surface of the pressure-sensitive adhesive layer opposite to the base material is attached to non-alkali glass, the pressure-sensitive adhesive layer is irradiated with energy rays. In, the adhesive force to the alkali-free glass of the pressure-sensitive adhesive sheet for glass dicing according to the present embodiment is preferably 50 to 250 mN/25 mm, particularly preferably 60 to 160 mN/25 mm, and further 70 to 130 mN/ It is preferably 25 mm. Since the adhesive force after irradiation with energy rays is 5000 mN/25 mm or more, it is possible to prevent the glass chip from being unintentionally peeled or displaced from the adhesive sheet in the stage before the glass chip is picked up from the adhesive sheet. .. On the other hand, when the adhesive force after irradiation with energy rays is 250 mN/25 mm or less, for example, when individually picking the cut glass chips, the glass chips can be picked up well without being damaged.

The adhesive force in the present specification is an adhesive force (mN/25 mm) measured by a 180° peeling method according to JIS Z0237:2009 using non-alkali glass as an adherend, and the details of the measuring method will be described later. It is as described in the test method.

5. Method for producing pressure-sensitive adhesive sheet for glass dicing The method for producing the pressure-sensitive adhesive sheet for glass dicing is not particularly limited as long as the pressure-sensitive adhesive layer formed from the above-mentioned pressure-sensitive adhesive composition can be laminated on one surface of the substrate.

As an example of the method for producing the pressure-sensitive adhesive sheet for glass dicing, first, the above-mentioned pressure-sensitive adhesive composition and, if desired, a coating composition further containing a solvent or a dispersion medium are prepared. Next, the coating composition is applied to one surface of the substrate by a die coater, a curtain coater, a spray coater, a slit coater, a knife coater or the like to form a coating film. Furthermore, the pressure-sensitive adhesive layer can be formed by drying the coating film. The property of the coating composition is not particularly limited as long as it can be applied. The component for forming the pressure-sensitive adhesive layer may be contained as a solute or a dispersoid in the coating composition.

When the coating composition contains a cross-linking agent (C), the above-mentioned drying conditions (temperature, time, etc.) may be changed in order to form a cross-linked structure with a desired existing density, or a heat treatment may be performed. It may be provided separately. In order to allow the crosslinking reaction to proceed sufficiently, after laminating the pressure-sensitive adhesive layer on the substrate by the above method or the like, the obtained pressure-sensitive adhesive sheet for glass dicing is placed in an environment of, for example, 23° C. and a relative humidity of 50% for 1 week. You may perform curing such as leaving it for about 2 weeks.

As another example of the method for producing the pressure-sensitive adhesive sheet for glass dicing, first, the coating composition is applied to the release-treated surface of the release film as described above to form a coating film. Next, the coating film is dried to form a laminate including the pressure-sensitive adhesive layer and the release film. Further, the surface of the pressure-sensitive adhesive layer of this laminate opposite to the release film is attached to a substrate. Through the above, a laminate of the pressure-sensitive adhesive sheet for glass dicing and the release film can be obtained. The release film in this laminate may be released as a process material, or the pressure-sensitive adhesive layer may be protected until it is attached to the adherend.

6. Method of Using Adhesive Sheet for Glass Dicing The adhesive sheet for glass dicing according to the present embodiment can be used for dicing a glass plate. The pressure-sensitive adhesive sheet for glass dicing according to this embodiment can also be used in a series of steps including dicing of a glass plate and subsequent pickup.

When used in a series of steps including dicing and subsequent pickup, first, the surface opposite to the base material in the adhesive layer of the adhesive sheet for glass dicing according to the present embodiment (hereinafter, referred to as “adhesive surface”). May be attached) to the glass plate. When the release film is laminated on the adhesive surface, the release film is removed and a glass plate is attached to the exposed adhesive surface. On the other hand, the peripheral portion of the adhesive surface is attached to an annular jig called a ring frame for transportation and fixing to the device. In addition, it is preferable to stand still for 10 to 120 minutes, especially to stand for 15 minutes to 60 minutes, and further 20 minutes to from the time of attaching the glass plate to the time of carrying out the subsequent dicing step. It is preferable to stand still for 40 minutes. By leaving still for such a period, the adhesion between the glass plate and the adhesive sheet can be made sufficient.

Then, a dicing process is performed. That is, the glass plate stuck on the pressure-sensitive adhesive sheet for glass dicing is cut using a dicing blade. Thereby, a plurality of glass chips attached on the pressure-sensitive adhesive sheet for glass dicing can be obtained. In the pressure-sensitive adhesive sheet for glass dicing according to this embodiment, since the pressure-sensitive adhesive layer is relatively thick as described above, excellent tack is exhibited. Thereby, the glass chip is favorably held on the adhesive sheet, and chip scattering during dicing is suppressed.

When the pressure-sensitive adhesive layer is composed of the energy ray-curable pressure-sensitive adhesive described above, after the dicing step, with respect to the pressure-sensitive adhesive sheet to which a plurality of glass chips are attached, the energy ray from the surface of the glass chip side or the surface of the base material side Irradiate. As a result, the polymerization reaction of the energy ray-curable group of the (meth)acrylic acid ester copolymer (A) proceeds, the adhesiveness is lowered, and the subsequent pickup step is facilitated.

The pickup step can be performed by a general-purpose means such as a suction collet. At this time, in order to facilitate the pickup, it is preferable to push up the target glass chip from the surface of the base material opposite to the pressure-sensitive adhesive layer with a pin or a needle.

An expanding step may be performed before the pickup step. In this case, the pressure-sensitive adhesive sheet for glass dicing is stretched in the plane direction. As a result, the gap between the glass chips is widened, and it becomes easier to pick up. The degree of extension may be set as appropriate in consideration of the preferable interval, the tensile strength of the base material, and the like. The expanding step may be performed before the energy ray irradiation.

In the case of dicing the glass plate using a glass dicing pressure-sensitive adhesive sheet according to the present embodiment, the area of the plane of the resulting glass tip is preferably ^{1 × 10 -6 mm 2 ~1mm 2} , 1 × more preferably 10 ^-4 mm ² ~0.25mm ^2, it is preferably particularly ^{2.5 × 10 -3 mm 2 ~0.09mm 2} , more in 0.01mm ² ~0.03mm ² Preferably. According to the pressure-sensitive adhesive sheet for glass dicing according to the present embodiment, the thickness of the pressure-sensitive adhesive layer is relatively large, and since good tack can be exhibited, even a small glass chip having an area in the above range, Chip scattering can be suppressed during dicing.

When a glass plate is diced using the pressure-sensitive adhesive sheet for glass dicing according to the present embodiment, the thickness of the glass plate used as a work is preferably 50 to 10000 μm, and particularly preferably 100 to 5000 μm. Is preferably 300 to 800 μm. In the present specification, the “work” refers to an adherend to which the pressure-sensitive adhesive sheet for glass dicing according to the present embodiment is attached, or a workpiece processed using the pressure-sensitive adhesive sheet.

The embodiments described above are described to facilitate the understanding of the present invention, and are not described to limit the present invention. Therefore, each element disclosed in the above-described embodiment is intended to include all design changes and equivalents within the technical scope of the present invention.

For example, another layer may be interposed between the base material and the pressure-sensitive adhesive layer in the pressure-sensitive adhesive sheet for glass dicing.

Hereinafter, the present invention will be described more specifically with reference to Examples and the like, but the scope of the present invention is not limited to these Examples and the like. In addition, the description of the mass part below is described as a solid content conversion value.

[Example 1]
(1) Preparation of (meth)acrylic acid ester copolymer (A) By copolymerizing 75 parts by mass of 2-ethylhexyl acrylate, 10 parts by mass of methyl methacrylate, and 15 parts by mass of 2-hydroxyethyl acrylate. An acrylic copolymer (AP) was obtained. When the molecular weight of the obtained acrylic copolymer (AP) was measured, the weight average molecular weight (Mw) was 700,000. The weight average molecular weight (Mw) in this example is a standard polystyrene equivalent weight average molecular weight measured (GPC measurement) using gel permeation chromatography (GPC).

Then, the obtained acrylic copolymer (AP) and 2-methacryloyloxyethyl isocyanate (MOI) as the energy ray-curable group-containing compound (A3) are combined with a zirconium chelate catalyst as the organometallic catalyst (D). (Matsumoto Fine Chemical Co., product name "ZC-700"). Thereby, a (meth)acrylic acid ester copolymer (A) having an energy ray-curable group (methacryloyl group) introduced into the side chain was obtained. At this time, both were reacted so that the MOI was 60 mol (60 mol %) per 100 mol of the 2-hydroxyethyl acrylate unit of the acrylic copolymer (AP). Moreover, the compounding quantity of the organometallic catalyst (D) was set to 0.1 part by mass with respect to 100 parts by mass of the acrylic copolymer (AP).

(2) Preparation of pressure-sensitive adhesive composition 100 parts by mass of (meth)acrylic acid ester copolymer (A) obtained in the above step (1), and α-hydroxycyclohexyl phenyl ketone as a photopolymerization initiator (BASF Corporation) (Product name "Irgacure 184") 3.0 parts by mass and trimethylolpropane-modified tolylene diisocyanate (manufactured by Tosoh Corporation, product name "Coronate L") 0.2 part by mass as a crosslinking agent (C) It mixed in, and the coating solution of the adhesive composition was obtained. An X-type pressure-sensitive adhesive can be obtained by using this pressure-sensitive adhesive composition.

(3) Preparation of pressure-sensitive adhesive sheet for glass dicing Release film obtained by subjecting the coating solution of the pressure-sensitive adhesive composition obtained in the above step (2) to a release treatment on one side of a polyethylene terephthalate film with a silicone-based release agent (manufactured by Lintec Co., Ltd., product The name "SP-PET381031", thickness: 38 [mu]m) was applied to a release-treated surface with a die coater. Then, it was treated at 100° C. for 1 minute to dry the coating film and allow the crosslinking reaction to proceed. In this way, a laminate including a release film and a pressure-sensitive adhesive layer having a thickness of 10 μm was obtained. Furthermore, a polyethylene terephthalate (PET) film (manufactured by Toyobo Co., Ltd., product name “A-4100”, thickness: 100 μm) was attached to the pressure-sensitive adhesive layer side surface of the laminate. Thus, a pressure-sensitive adhesive sheet for glass dicing was obtained in which the base material, the pressure-sensitive adhesive layer, and the release film were laminated in this order.

[Examples 2 to 11]
Of the material of the substrate, the thickness of the substrate, the amount of 2-methacryloyloxyethyl isocyanate (MOI) used to form the pressure-sensitive adhesive layer, and the organometallic catalyst (D) used to form the pressure-sensitive adhesive layer. A pressure-sensitive adhesive sheet for glass dicing was produced in the same manner as in Example 1 except that the type and the thickness of the pressure-sensitive adhesive layer were changed as shown in Table 1.

[Comparative Examples 1 and 2]
A pressure-sensitive adhesive sheet for glass dicing was prepared in the same manner as in Example 1, except that the type of the organometallic catalyst (D) used to form the pressure-sensitive adhesive layer and the thickness of the pressure-sensitive adhesive layer were changed as shown in Table 1. Manufactured.

Details of the abbreviations and the like described in Table 1 are as follows.
[Substrate material]
PET (thickness 100 μm): polyethylene terephthalate film (manufactured by Toyobo Co., Ltd., product name “A-4100”)
PET (thickness 50 μm): polyethylene terephthalate film (manufactured by Toyobo Co., Ltd., product name “A-4100”)
PO: Polyolefin film (manufactured by RIKEN TECHNOS, product name "ADN09-100T-M8")
PP: Polypropylene film (manufactured by Diamond Plus Film, product name "PL109")
PI: Polyimide film (manufactured by MPRTECH, product name “Mordohar PIF100”)
[Organometallic catalyst]
Zr: Zirconium chelate catalyst (manufactured by Matsumoto Fine Chemical Co., product name "ZC-700")
Sn: dibutyltin laurylate catalyst (manufactured by Toyochem, product name "BXX-3778")

[Test Example 1] (Measurement of Storage Elastic Modulus of Base Material)
With respect to the base materials used in the examples and comparative examples, the storage elastic modulus at 23° C. was measured by the following apparatus and conditions. The results are shown in Table 1.
Measuring device: Dynamic elastic modulus measuring device, manufactured by TA Instruments, product name "DMA Q800"
Test start temperature: 0℃
Test end temperature: 200℃
Temperature rising rate: 3°C/min Frequency: 11Hz
Amplitude: 20 μm

[Test Example 2] (Measurement of storage elastic modulus of pressure-sensitive adhesive layer before ultraviolet irradiation)
The coating solution of the pressure-sensitive adhesive composition used in Examples and Comparative Examples was applied onto the release-treated surface of a 38 μm-thick first release film (manufactured by Lintec Co., Ltd., product name “SP-PET381031”). The coating film was dried by holding the obtained coating film at 100° C. for 1 minute. As a result, a pressure-sensitive adhesive layer having a thickness of 40 μm was formed on the first release film. Further, a release-treated surface of a second release film having a thickness of 38 μm (manufactured by Lintec Co., product name “SP-PET381031”) is attached to the surface of the pressure-sensitive adhesive layer opposite to the first release film, A laminate was obtained by laminating the first release film, the adhesive layer having a thickness of 40 μm, and the second release film in this order. A plurality of pressure-sensitive adhesive layers obtained by the above procedure were laminated to a thickness of 800 μm. The laminate having a thickness of 800 μm was punched out into a circular shape having a diameter of 10 mm to obtain a sample for measurement. A viscoelasticity measuring device (TA Instruments, product name “ARES”) was applied to the sample to give a strain of frequency 1 Hz, and the storage elastic modulus at −50 to 150° C. was measured to determine the storage elastic modulus at 23° C. and 100° C. Got the value. The results are shown in Table 1. When a plurality of pressure-sensitive adhesive layers were laminated, the laminate used was one that had been left for one week in an environment of a temperature of 23° C. and a humidity of 50% after forming the pressure-sensitive adhesive layers.

[Test Example 3] (Measurement of Tensile Elastic Modulus of Adhesive Layer After UV Irradiation)
By the same procedure as in Test Example 2, a plurality of pressure-sensitive adhesive layers were laminated to have a thickness of 200 μm.

Subsequently, an ultraviolet ray irradiation device (manufactured by Lintec Co., Ltd., product name “RAD-2000”) is used to perform ultraviolet ray (UV) irradiation (illuminance: 230 mW/cm ² , light quantity: 190 mJ/cm ² ) to obtain an adhesive layer. Was cured. Further, it was cut into 15 mm×140 mm to obtain a test piece.

The release film was peeled from the obtained test piece, and the cured adhesive layer was measured for the tensile elastic modulus at 23° C. according to JIS K7161:1994 and JIS K7127:1999. Specifically, a tensile tester (manufactured by Shimadzu Corporation, product name "Autograph AG-IS 500N") was used to set a chuck distance of 100 mm, and then a tensile test was performed at a speed of 200 mm/min to obtain a tensile elastic modulus. (Pa) was measured. The results are shown in Table 1.

[Test Example 4] (measurement of tack value)
For the surface of the pressure-sensitive adhesive layer side of the pressure-sensitive adhesive sheets manufactured in Examples and Comparative Examples, a tack value was measured by a probe tack tester (Resc Co., product name “RPT-100”) using a probe having a diameter of 5 mm (5 mmφ). Was measured. The measuring method was the method described in JIS Z0237:2009, while the peeling speed was changed to 1 mm/min, the load was 100 gf/cm ² , and the contact time was 1 second, as described in the above JIS regulations. The measured energy amount (peak integrated value) was determined and used as the tack value (unit: mJ/5 mmφ). The results are shown in Table 1. In addition, the above-mentioned measurement used the adhesive sheet left for 1 week in the environment of temperature 23 degreeC and 50% of humidity after forming an adhesive layer.

[Test Example 5] (Measurement of adhesive strength before and after ultraviolet irradiation)
The release film was peeled from the pressure-sensitive adhesive sheet for glass dicing, which was manufactured at room temperature in Examples and Comparative Examples and left for 1 week in an environment of a temperature of 23° C. and a humidity of 50%. The exposed surface of the pressure-sensitive adhesive layer was superposed on one surface of a 6-inch alkali-free glass plate, and a load of 2 kg roller was reciprocated once to bond them together, and left for 20 minutes. After that, by a 180° peeling method according to JIS Z0237:2009, the pressure-sensitive adhesive sheet for glass dicing was peeled from a non-alkali glass plate at a peeling speed of 300 mm/min and a peeling angle of 180° to give an adhesive force (mN/25 mm). Was measured. This measured value was defined as the adhesive strength before ultraviolet irradiation. The results are shown in Table 1.

Further, in the same manner as above, the pressure-sensitive adhesive sheet for glass dicing and the 6-inch non-alkali glass plate produced in Examples and Comparative Examples were laminated and left for 20 minutes, then from the substrate side of the pressure-sensitive adhesive sheet for glass dicing. UV (UV) irradiation (illuminance: 200 mW/cm ² , light quantity: 180 mJ/cm ² ) was performed using an ultraviolet irradiation device (manufactured by Lintec Co., Ltd., product name “RAD-2000”) to cure the adhesive layer. .. Then, the adhesive force (mN/25 mm) was measured in the same manner as above. This measured value was used as the adhesive strength after ultraviolet irradiation. The results are shown in Table 1.

[Test Example 6] (Evaluation of chip scattering)
The release film was peeled off from the pressure-sensitive adhesive sheet for glass dicing, which was produced in Examples and Comparative Examples and left for 1 week in an environment of temperature 23° C. and humidity 50%, and a tape mounter (manufactured by Lintec Co., product name “Adwill RAD 2500 m/ 12”) was used to attach a 6-inch alkali-free glass plate having a thickness of 550 μm and a ring frame for dicing to the exposed surface of the pressure-sensitive adhesive layer. Then, the pressure-sensitive adhesive sheet for glass dicing was cut according to the outer diameter of the ring frame. Further, using a dicing device (manufactured by DISCO, product name “DFD-651”), dicing was performed from the glass plate side under the following dicing conditions to obtain a 0.6 mm square glass chip.

<Dicing conditions>
・Dicing device: Disco DFD-651
・Blade: NBC-2H 2050 27HECC manufactured by DISCO
・Blade width: 0.025 to 0.030 mm
・Blade amount: 0.640 to 0.760 mm
・Blade rotation speed: 30000 rpm
・Cutting speed: 80 mm/sec
・Substrate depth of cut: 20 μm
・Cutting water volume: 1.0 L/min
・Cutting water temperature: 20℃
・Dicing size: 0.6 mm square (plane area is 0.36 mm ² ).

By visually observing the pressure-sensitive adhesive sheet to which the glass chips obtained by the dicing process are attached, count the number of glass chips that have fallen off the pressure-sensitive adhesive sheet during the dicing process, and divide that number by the number of divisions in the dicing process. Then, the chip scattering rate (unit: %) was obtained. Based on the calculation result, chip scattering was evaluated based on the following criteria. The evaluation results are shown in Table 1.
A: The chip scattering rate is less than 0.1%.
◯: The chip scattering rate is 0.1% or more and less than 5%.
Δ: Chip scattering rate is 5% or more and less than 10%.
X: The chip scattering rate is 10% or more.

As can be seen from Table 1, the pressure-sensitive adhesive sheets according to the examples can suppress chip scattering during dicing.

The pressure-sensitive adhesive sheet for glass dicing according to the present invention is used in a glass dicing process, and particularly preferably used in a thin glass dicing process.

Claims (8)

A method for producing a pressure-sensitive adhesive sheet for glass dicing, comprising a base material and a pressure-sensitive adhesive layer laminated on at least one surface of the base material,
The thickness of the adhesive layer, 9 .mu.m than state, and are less 40 [mu] m,
The manufacturing method,
An acrylic copolymer (AP) obtained by copolymerizing at least a (meth)acrylic acid alkyl ester monomer (A1) and a functional group-containing monomer (A2) having a reactive functional group,
An energy ray-curable group-containing compound (A3) having a functional group capable of reacting with the functional group of the functional group-containing monomer (A2) and an energy ray-curable carbon-carbon double bond;
To prepare a (meth)acrylic acid ester copolymer (A) having an energy ray-curable group introduced into its side chain, and
A step of laminating a pressure-sensitive adhesive layer on at least one surface of a substrate using the pressure-sensitive adhesive composition containing the (meth)acrylic acid ester copolymer (A).
Including,
The reaction between the acrylic copolymer (AP) and the energy ray-curable group-containing compound (A3) is performed by at least one organometallic catalyst selected from an organic compound containing zirconium and an organic compound containing titanium. The method for producing a pressure-sensitive adhesive sheet for glass dicing, which is performed in the presence of (D) . In the pressure-sensitive adhesive layer, the amount of energy measured using a probe tack under the condition that the peeling speed is changed to 1 mm/min in the method described in JIS Z0237: 1991 is 0.01 to 5 mJ/5 mmφ. The method for producing a pressure-sensitive adhesive sheet for glass dicing according to claim 1 . The method for producing a pressure-sensitive adhesive sheet for glass dicing according to claim 1 or 2 , wherein the pressure-sensitive adhesive layer has a storage elastic modulus at 23°C of 30 to 100 kPa. The surface of the pressure-sensitive adhesive layer opposite to the substrate is attached to non-alkali glass, and the adhesive strength of the pressure-sensitive adhesive sheet for glass dicing to the non-alkali glass after standing for 20 minutes is 5000 to 25000 mN/. method of manufacturing a glass adhesive sheet according to any one of claim 1 to 3, characterized in that it is 25 mm. The surface of the pressure-sensitive adhesive layer opposite to the substrate is attached to non-alkali glass, and after irradiating the pressure-sensitive adhesive layer with energy rays, the pressure-sensitive adhesive sheet for glass dicing to the non-alkali glass is adhered. force, method of manufacturing a glass adhesive sheet according to any one of claims 1 to 4, characterized in that a 50~250mN / 25mm. The pressure-sensitive adhesive composition further contains an energy ray-curable compound (B) other than the (meth)acrylic acid ester copolymer (A) , according to any one of claims 1 to 5. A method for producing the pressure-sensitive adhesive sheet for glass dicing as described above. The method for producing a pressure-sensitive adhesive sheet for glass dicing according to any one of claims 1 to 6 , wherein the pressure-sensitive adhesive composition further contains a crosslinking agent (C). The adhesive sheet for glass dicing, a glass plate, either plane according to claim 1-7, characterized in that is for dicing glass tip having an area of 1 × 10 ^-6 mm ² ~1mm ² The method for producing a pressure-sensitive adhesive sheet for glass dicing according to any one of claims 1 to 5.