JP7421498B2 - Film adhesive, laminate sheet, composite sheet, and method for producing laminate - Google Patents

Description

The present invention relates to a method for producing a film adhesive, a laminated sheet, a composite sheet, and a laminated body.
This application claims priority based on Japanese Patent Application No. 2018-246838 filed in Japan on December 28, 2018, the contents of which are incorporated herein.

BACKGROUND ART When manufacturing or processing various parts that constitute electronic devices, various film adhesives are used depending on the purpose.
For example, when attaching a semiconductor chip to the circuit forming surface of a board, a film adhesive is pasted on the back side of the semiconductor chip, and the semiconductor chip is attached to the circuit forming surface of the board through this film adhesive. Adhesion (die bonding). In addition, when protecting the circuit-forming surface of a chip such as a sensor, the circuit-forming surface is covered with a light-transmissive cover via a film-like adhesive having light-transmissive properties.

On the other hand, components provided with such a film adhesive may be exposed to high temperatures during a heating process such as a solder reflow process. In that case, deterioration of the film adhesive due to the influence of heat may become a problem. For example, if a film-like adhesive that is transparent to light changes color, it becomes difficult to read information through the film-like adhesive. Film adhesives contain resin components to exhibit adhesive properties, and in some cases contain thermosetting components to impart thermosetting properties. Some are unstable to heat. That is, conventional film adhesives tend to change color when heated.

As a film-like adhesive having light transparency, for example, a die bonding film is disclosed which is used for die bonding of semiconductor chips and has a light transmittance of 80% or more at a wavelength of 1065 nm (see Patent Document 1).

Japanese Patent No. 6310748

However, Patent Document 1 does not disclose physical properties after heating, such as the color of the die-bonding film after heating.

The present invention provides a film adhesive that has light transmittance before and after heating and suppresses discoloration after heating, a laminated sheet and a composite sheet using the film adhesive, and a film adhesive that uses the film adhesive. The purpose of the present invention is to provide a method for manufacturing a laminate.

The present invention provides a film adhesive for bonding a circuit-forming surface of a chip and a light-transmitting cover, wherein one surface of the film adhesive before being heated at 260°C is exposed to X-rays. The surface of the film-like adhesive on which the V _{1 was} measured after being analyzed by photoelectron spectroscopy to measure the phosphorus concentration V ₁ and heating at 260° C. for 10 minutes. When the phosphorus concentration V ₂ is measured by X-ray photoelectron spectroscopy, the V ₁ is 0.1 atomic % or more, and the phosphorus concentration calculated from the V ₁ and V ₂ decreases. The present invention provides a film adhesive having an adhesive ratio of 25% or less.
In the film adhesive of the present invention, the film adhesive has a linear transmittance of 90% or more for light having a wavelength of 400 to 800 nm before being heated at 260°C, and the film adhesive is heated at 260°C for 10 minutes. The film adhesive may have a linear transmittance of 85% or more for light having a wavelength of 400 to 800 nm, and a thickness of the film adhesive may be 10 to 40 μm.
The film adhesive of the present invention may contain an aliphatic epoxy compound.
The film adhesive of the present invention contains a phenolic resin (b2), and the content ratio of the phenolic resin (b2) to the total mass of the film adhesive in the film adhesive is 10% by mass. % or less.

The film adhesive of the present invention may contain an aliphatic phosphite as an antioxidant.
In the film adhesive of the present invention, the film adhesive contains an acrylic resin and an aliphatic polyvalent isocyanate crosslinking agent, and the acrylic resin contains a functional group capable of bonding with the crosslinking agent. It may have a group.
The present invention provides a laminated sheet including the film adhesive and a resin film provided on one surface of the film adhesive.
The present invention includes the film adhesive and a dicing sheet provided on one surface of the film adhesive, and the dicing sheet includes a base material and one surface of the base material. and an adhesive layer provided thereon, the adhesive layer being disposed between the base material and the film adhesive.
In the present invention, the circuit-forming surface of the chip is bonded to one surface of the film-like adhesive, and a light-transmitting cover is bonded to the other surface of the film-like adhesive. The present invention provides a method for producing a laminate, which obtains a laminate in which a film adhesive and the light-transmitting cover are laminated in this order.

The film adhesive of the present invention has light transmittance before and after heating, and coloration after heating is suppressed.
By using the laminated sheet or composite sheet of the present invention provided with the film adhesive of the present invention, the film adhesive can be provided on the component to which it is applied.
According to the method for manufacturing a laminate of the present invention, a laminate including a chip, a film adhesive, and a light-transmitting cover can be manufactured in this order.

FIG. 1 is a cross-sectional view schematically showing an example of a film adhesive and a laminated sheet according to an embodiment of the present invention. FIG. 3 is a cross-sectional view schematically showing another example of a laminated sheet according to an embodiment of the present invention. FIG. 1 is a cross-sectional view schematically showing an example of a composite sheet according to an embodiment of the present invention. FIG. 1 is a cross-sectional view schematically showing an example of a laminate manufactured using a film adhesive according to an embodiment of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view schematically illustrating an example of how to use a composite sheet according to an embodiment of the present invention.

◇Film-like adhesive The film-like adhesive according to one embodiment of the present invention is a film-like adhesive for bonding the circuit-forming surface of a chip and a light-transmitting cover, and is heated at 260°C. One surface of the film adhesive was analyzed by X-ray photoelectron spectroscopy (herein sometimes abbreviated as "XPS"), and the phosphorus concentration (herein, sometimes abbreviated as "XPS") was analyzed. (sometimes abbreviated as "P concentration") _V1 was measured, and the surface of the film adhesive after measuring _V1 and heating at 260°C for 10 minutes, where _V1 was measured. When the phosphorus concentration (P concentration) _V2 was measured by X-ray photoelectron spectroscopy (XPS), the _V1 was 0.1 atomic% or more, and it was calculated from the _V1 and _V2. The rate of decrease in the concentration of phosphorus (herein sometimes abbreviated as "rate of decrease in P concentration") is 25% or less.

Examples of film adhesives that satisfy the conditions of V ₁ , V ₂ and the above-mentioned reduction rate include those containing a trivalent phosphorus compound. Such a film-like adhesive suppresses turbidity and coloring before and after heating at 260°C, etc., and allows light with a wavelength of 400 to 800 nm (hereinafter referred to as "light (400 to 800 nm)"). (sometimes abbreviated) has high in-line transmittance.

The film-like adhesive of this embodiment can be used for adhering objects during manufacturing or processing of various parts constituting electronic devices.
For example, the circuit-forming surface of a chip such as a sensor can be covered with a light-transmissive cover (protective cover) via the film adhesive. That is, the film adhesive can be used as a film for bonding the cover to the circuit forming surface of the chip.
In that case, as mentioned above, the film adhesive has high light transmittance before and after heating, and coloring is suppressed, so the visual field that exists on the circuit forming surface of the chip can be seen through the light transmitting cover and the film adhesive. Information can be viewed stably and with high precision.

Examples of the sensor to be covered with the light-transmissive cover (protective cover) include a fingerprint sensor. However, this is just an example of a sensor.

In this specification, the surface of the substrate and the chip on which the circuit is formed is referred to as the "circuit formation surface."
Note that in this specification, the term "chip" does not mean only semiconductor chips, but also includes chips other than semiconductor chips.

The film adhesive of this embodiment preferably has thermosetting properties, and preferably has pressure-sensitive adhesive properties. For example, a film adhesive having both thermosetting and pressure-sensitive adhesive properties can be applied to various adherends by lightly pressing it in an uncured state. Further, the film adhesive may be one that can be applied to various adherends by heating and softening it. When the film adhesive is cured, it ultimately becomes a cured product with high impact resistance, and this cured product can maintain sufficient adhesive properties even under severe high temperature and high humidity conditions.

The linear transmittance of light (400 to 800 nm) of the film adhesive of this embodiment before heating at 260°C (herein sometimes abbreviated as "in-line transmittance before heating") is: It is preferably 90% or more, more preferably 91.5% or more, even more preferably 93% or more, and particularly preferably 94.5% or more. When the in-line transmittance before heating is equal to or higher than the lower limit value, the film adhesive before heating has a property that allows the image to be correctly recognized when viewed through the film adhesive (hereinafter referred to as (sometimes abbreviated as "image recognizability") is high.

The upper limit of the in-line transmittance of light (400 to 800 nm) before heating is not particularly limited, and may be 100%.
For example, a film adhesive having an in-line transmittance before heating of 99.8% or less is easier to manufacture.

The in-line transmittance of light (400 to 800 nm) before heating can be adjusted as appropriate within a range set by any combination of any of the above lower limit values and upper limit values. For example, in one embodiment, the linear transmittance before heating is preferably 90 to 99.8%, more preferably 91.5 to 99.8%, and more preferably 93 to 99.8%. It is more preferably 94.5% to 99.8%. However, these are examples of the linear transmittance before heating.

Linear transmittance of light (400 to 800 nm) of the film adhesive of this embodiment after heating at 260 ° C. for 10 minutes (in this specification, it may be abbreviated as "linear transmittance after heating") is preferably 85% or more, and may be, for example, 87.5% or more, 90% or more, or 92% or more. When the in-line transmittance after heating is equal to or greater than the lower limit value, the film-like adhesive after heating has high image recognizability.

The upper limit of the linear transmittance of light (400 to 800 nm) after heating is: It is not particularly limited, and may be 100%.
For example, a film adhesive having an in-line transmittance of 99.8% or less after heating is easier to manufacture.

The linear transmittance of light (400 to 800 nm) after heating can be adjusted as appropriate within a range set by any combination of any of the lower and upper limits described above. For example, in one embodiment, the linear transmittance after heating is preferably 85 to 99.8%, such as 87.5 to 99.8%, 90 to 99.8%, and 92 to 99.8%. It may be either 8%. However, these are examples of the linear transmittance after heating.

The linear transmittance of light (400 to 800 nm) before heating and after heating can be measured by a known method using a spectrophotometer.

The heating conditions for the film adhesive of 260° C. and 10 minutes when defining the linear transmittance after heating are set in consideration of the conditions in a heating process such as a solder reflow process.

The shear strength of the film adhesive of this embodiment is not particularly limited, but is preferably 20N/2mm□ or more, for example, 50N/2mm□ or more, 60N/2mm□ or more, 70N/2mm□ or more, and It may be 80N/2mm□ or more. When the shear strength of the film adhesive is greater than or equal to the lower limit, the adhesive force to the object to which it is applied becomes stronger.
In addition, in this specification, the unit "N/2mm□" is synonymous with "N/(2mm×2mm)".

The upper limit of the shear strength of the film adhesive is also not particularly limited.
For example, a film adhesive having a shear strength of 300 N/2 mm□ or less is easier to manufacture.

The shear strength of the film-like adhesive can be adjusted as appropriate within a range set by arbitrarily combining any of the above lower limit values and upper limit values. For example, in one embodiment, the shear strength is preferably 20 to 300N/2mm□, such as 50 to 300N/2mm□, 60 to 300N/2mm□, 70 to 300N/2mm□, and 80 to 300N/2mm□. It may be either 300N/2mm□. However, these are examples of the shear strength.

In this embodiment, the shear strength of the film adhesive was measured by the method shown below.
(Method for measuring shear strength of film adhesive)
Using a film adhesive with a size of 2 mm x 2 mm and a thickness of 20 μm, a copper plate with a size of 30 mm x 30 mm and a thickness of 300 μm, and a silicon chip, A test piece is prepared in which the entire surface of one side is attached to the surface of the silicon chip and the entire surface of the other side is attached to the surface of the copper plate. On at least one side of this test piece, the film adhesive and the silicon chip are aligned.
Under a temperature condition of 23° C., on the side surface of the test piece where the alignment was performed, for both the film adhesive and the silicon chip, and for the other surface of the film adhesive. A force is applied at a speed of 200 μm/s in the parallel direction, and the maximum value of the force applied until the film adhesive breaks is determined as the shear strength of the film adhesive (N/2 mm □ ).

When XPS analysis was performed on one side of the film adhesive before heating at 260° C. and the P concentration V ₁ was measured, V ₁ was 0.1 atomic % or more, and 0.12 atomic % or more. The content is preferably 0.14 atomic % or more, more preferably 0.14 atomic % or more, and may be either 0.2 atomic % or more, or 0.3 atomic % or more, for example. When V ₁ is equal to or greater than the lower limit, the effect of suppressing coloring of the film adhesive before heating (for example, heating at 260° C.) becomes high.

The upper limit of _V1 is not particularly limited.
For example, a film adhesive having a V ₁ of 0.5 atomic % or less is easier to manufacture.

_V1 can be adjusted as appropriate within a range set by arbitrarily combining any of the above lower limit values and upper limit values. For example, in one embodiment, V ₁ is preferably from 0.1 to 0.5 atomic %, more preferably from 0.12 to 0.5 atomic %, and more preferably from 0.14 to 0.5 atomic %. %, and may be, for example, either 0.2 to 0.5 atomic % or 0.3 to 0.5 atomic %.

After measuring V ₁ and heating at 260° C. for 10 minutes, XPS analysis was performed on the measurement surface of V ₁ and the P concentration V ₂ was measured. V ₂ was , preferably 0.1 atomic % or more, more preferably 0.12 atomic % or more, even more preferably 0.14 atomic % or more, for example, 0.2 atomic % or more, and 0 .3 atomic% or more. When V ₂ is equal to or greater than the lower limit, the effect of suppressing coloring of the film adhesive after heating (for example, heating at 260° C.) becomes higher.

The upper limit of _V2 is not particularly limited.
For example, a film adhesive with a V ₂ of 0.5 atomic % or less is easier to manufacture.

_V2 can be adjusted as appropriate within a range set by arbitrarily combining any of the above lower limit values and upper limit values. For example, in one embodiment, V ₂ is preferably from 0.1 to 0.5 atomic %, more preferably from 0.12 to 0.5 atomic %, and more preferably from 0.14 to 0.5 atomic %. %, and may be, for example, either 0.2 to 0.5 atomic % or 0.3 to 0.5 atomic %.

V ₁ and V ₂ can be measured by survey scanning an area of 0.1 mm x 1 mm on one side of a film adhesive having a thickness of 20 μm and performing XPS analysis. At this time, the measurement angle is 45° and the beam diameter is 18 μm. For example, aluminum can be used as the X-ray source.

The P concentration reduction rate calculated from the V ₁ and V ₂ is 25% or less, preferably 20% or less, more preferably 15% or less, for example, 10% or less, 7.5 % or less, or 5% or less. When the P concentration reduction rate is below the upper limit value, the effect of suppressing coloring of the film adhesive after heating (for example, heating at 260° C.) becomes high.

The lower limit of the P concentration reduction rate is not particularly limited.
For example, a film adhesive whose P concentration decrease rate is 1% or more is easier to manufacture.

The P concentration reduction rate can be adjusted as appropriate within a range set by arbitrarily combining the above-mentioned lower limit value and any of the upper limit values. For example, in one embodiment, the P concentration reduction rate is preferably 1 to 25%, more preferably 1 to 20%, even more preferably 1 to 15%, for example, 1 to 10%. %, 1 to 7.5%, and 1 to 5%.

The P concentration reduction rate can be calculated using the following formula.
P concentration decrease rate = (V ₁ - V ₂ )/V ₁ ×100

In the film adhesive, at least one surface thereof satisfies the above-mentioned conditions of V ₁ , V ₂ and P concentration reduction rate, and both surfaces satisfy the above-mentioned conditions of V ₁ , V ₂ and P concentration reduction rate. It is preferable to meet the requirements.
The single-layer film adhesive usually has no deviation in its composition and has a high compositional uniformity. Therefore, there is no significant difference in the type and content of the components on both sides of the single-layer film adhesive, or even if there is, the effect brought about by it is negligible. Minor.
In the single-layer film adhesive, if at least one surface thereof satisfies the above-mentioned conditions of V ₁ , V ₂ and P concentration reduction rate, any cross section of the film adhesive and the other surface It can also be determined that the above-mentioned conditions of V ₁ , V ₂ and P concentration reduction rate are satisfied.

The film-like adhesive may be composed of one layer (single layer) or may be composed of two or more layers, and when it is composed of multiple layers, these multiple layers may be the same as each other. However, they may be different, and the combination of these multiple layers is not particularly limited.

Note that in this specification, "the multiple layers may be the same or different from each other" refers to "all the layers may be the same or all the layers may be the same or different", not only in the case of film adhesives. "The layers may be different, or only some of the layers may be the same." Furthermore, "the layers are different from each other" means "at least one of the constituent materials and thicknesses of each layer may be different from each other." It means "different".

The thickness of the film adhesive is preferably 10 to 40 μm, for example, it may be any of 10 to 35 μm, 10 to 30 μm, and 10 to 25 μm, or 13 to 40 μm, and 16 to 40 μm. , and 19 to 40 μm, or may be 13 to 35 μm, 16 to 30 μm, and 19 to 25 μm. When the thickness of the film adhesive is equal to or greater than the lower limit, the adhesive force of the film adhesive to the object to be bonded becomes stronger. When the thickness of the film adhesive is equal to or less than the upper limit value, the linear transmittance of light (for example, light (400 to 800 nm)) of the film adhesive becomes high regardless of the presence or absence of heating.
Here, the "thickness of a film adhesive" means the thickness of the entire film adhesive. For example, the thickness of a film adhesive consisting of multiple layers refers to the total thickness of the film adhesive. means the total thickness of the layers.

Preferably, the film adhesive has, for example, a linear transmittance of light (400 to 800 nm) before heating of 90% or more, and a linear transmittance of light (400 to 800 nm) after heating of 85% or more. and the thickness of the film adhesive is 10 to 40 μm.

The above-mentioned physical properties of the film adhesive (the linear transmittance of light (400 to 800 nm) before heating, the linear transmittance of light (400 to 800 nm) after heating, shear strength, V ₁ and V ₂ ) are as follows: For example, it can be adjusted by adjusting the type and content of the components contained in the film adhesive.

Preferable examples of the film adhesive include one or two selected from the group consisting of an acrylic resin (a), an epoxy compound (b1), and a phosphorus antioxidant (z). Examples include those containing the above.

<<Adhesive composition>>
The film adhesive is made of one or two constituent materials selected from the group consisting of an acrylic resin (a), an epoxy compound (b1), and a phosphorus antioxidant (z). It can be formed using an adhesive composition containing the above). For example, by applying an adhesive composition to the surface on which the film adhesive is to be formed and drying it as necessary, the film adhesive can be formed at the target site.
The content ratio of components that do not vaporize at room temperature in the adhesive composition is usually the same as the content ratio of the components in the film adhesive. In this specification, "normal temperature" means a temperature that is not particularly cooled or heated, that is, a normal temperature, and includes, for example, a temperature of 15 to 25°C.

The adhesive composition may be applied by a known method, such as an air knife coater, blade coater, bar coater, gravure coater, roll coater, roll knife coater, curtain coater, die coater, knife coater, or screen coater. , a method using various coaters such as a Meyer bar coater and a kiss coater.

The drying conditions for the adhesive composition are not particularly limited, but when the adhesive composition contains a solvent described below, it is preferable to dry the adhesive composition by heating. The adhesive composition containing a solvent is preferably dried at, for example, 70 to 130° C. for 10 seconds to 5 minutes.
Hereinafter, the components contained in the film adhesive and the adhesive composition will be explained in detail.

<Acrylic resin (a)>
The acrylic resin (a) is a component that can be considered to be formed by a polymerization reaction of one or more selected from the group consisting of (meth)acrylic acid, (meth)acrylic acid ester, and derivatives thereof. be.
Note that the term "derivative" as used herein means a structure in which one or more groups of the original compound are substituted with other groups (substituents), unless otherwise specified. Here, the term "group" includes not only an atomic group formed by bonding a plurality of atoms, but also a single atom.
The acrylic resin (a) is a resin component that imparts film-forming properties, flexibility, etc. to the film adhesive, and improves adhesion (applicability) to an object to be bonded such as the chip.

In this specification, "(meth)acrylic acid" is a concept that includes both "acrylic acid" and "methacrylic acid." The same applies to terms similar to (meth)acrylic acid.

The adhesive composition and the film adhesive may contain only one type of acrylic resin (a), or two or more types, and in the case of two or more types, the combination and ratio thereof can be arbitrarily selected. .

Examples of the acrylic resin (a) include known acrylic polymers.
The weight average molecular weight (Mw) of the acrylic resin (a) is preferably from 10,000 to 2,000,000, more preferably from 100,000 to 1,500,000. When the weight average molecular weight of the acrylic resin (a) is within such a range, it becomes easy to adjust the adhesive force between the film adhesive and the adherend to a preferable range.
On the other hand, when the weight average molecular weight of the acrylic resin (a) is greater than or equal to the lower limit, the shape stability (stability over time during storage) of the film adhesive is improved. In addition, since the weight average molecular weight of the acrylic resin (a) is less than or equal to the above upper limit, the film adhesive can easily follow the uneven surface of the adherend, and there is a gap between the adherend and the film adhesive. This further suppresses the occurrence of voids, etc.
In this specification, the "weight average molecular weight" is a polystyrene equivalent value measured by gel permeation chromatography (GPC) unless otherwise specified.

The glass transition temperature (Tg) of the acrylic resin (a) is preferably -60 to 70°C, more preferably -30 to 50°C. When the Tg of the acrylic resin (a) is equal to or higher than the lower limit value, the adhesive force between the film adhesive and the adherend is suppressed, and for example, when picking up the adhesive, the adhesive force between the film adhesive and the adherend is suppressed. The chips can be more easily separated from the dicing sheet, which will be described later. When the Tg of the acrylic resin (a) is below the upper limit, the adhesive force between the film adhesive and the adherend is improved.

Examples of the (meth)acrylic ester constituting the acrylic resin (a) include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, and isopropyl (meth)acrylate. , n-butyl (meth)acrylate, isobutyl (meth)acrylate, sec-butyl (meth)acrylate, tert-butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, ( Heptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, n-octyl (meth)acrylate, n-nonyl (meth)acrylate, isononyl (meth)acrylate, (meth) Decyl acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate (lauryl (meth)acrylate), tridecyl (meth)acrylate, tetradecyl (meth)acrylate (myristyl (meth)acrylate), (meth)acrylate ) Alkyl constituting an alkyl ester such as pentadecyl acrylate, hexadecyl (meth)acrylate (palmityl (meth)acrylate), heptadecyl (meth)acrylate, octadecyl (meth)acrylate (stearyl (meth)acrylate), etc. (meth)acrylic acid alkyl ester in which the group has a chain structure having 1 to 18 carbon atoms;
(meth)acrylic acid cycloalkyl esters such as isobornyl (meth)acrylate and dicyclopentanyl (meth)acrylate;
(meth)acrylic acid aralkyl esters such as benzyl (meth)acrylate;
(meth)acrylic acid cycloalkenyl ester such as (meth)acrylic acid dicyclopentenyl ester;
(meth)acrylic acid cycloalkenyloxyalkyl ester such as (meth)acrylic acid dicyclopentenyloxyethyl ester;
(meth)acrylic acid imide;
Glycidyl group-containing (meth)acrylic esters such as glycidyl (meth)acrylate;
Hydroxymethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, (meth)acrylate ) Hydroxyl group-containing (meth)acrylic acid esters such as 3-hydroxybutyl acrylate and 4-hydroxybutyl (meth)acrylate;
Examples include substituted amino group-containing (meth)acrylic esters such as N-methylaminoethyl (meth)acrylate. Here, the term "substituted amino group" means a group having a structure in which one or two hydrogen atoms of the amino group are substituted with groups other than hydrogen atoms.

The acrylic resin (a) may be, for example, one or two selected from (meth)acrylic acid, itaconic acid, vinyl acetate, acrylonitrile, styrene, N-methylolacrylamide, etc. in addition to the (meth)acrylic acid ester. A resin obtained by copolymerizing the above monomers may also be used.

The number of monomers constituting the acrylic resin (a) may be one, or two or more, and when there are two or more, the combination and ratio thereof can be arbitrarily selected.

In addition to the above-mentioned hydroxyl group, the acrylic resin (a) may have a functional group capable of bonding with other compounds, such as a vinyl group, (meth)acryloyl group, amino group, carboxy group, or isocyanate group. These functional groups, including the hydroxyl group of the acrylic resin (a), may be bonded to other compounds via the crosslinking agent (f) described below, or may be bonded to other compounds without the crosslinking agent (f). It may be directly combined with When the acrylic resin (a) is bonded to other compounds through the functional group, the reliability of the package obtained using the film adhesive tends to be improved.

Preferred examples of the acrylic resin (a) include those having a functional group capable of bonding with the crosslinking agent (f) described below.

In the adhesive composition, the ratio of the content of the acrylic resin (a) to the total content of all components other than the solvent (i.e., the ratio of the content of the acrylic resin (a) to the total mass of the film adhesive in the adhesive composition) The content ratio of a) is preferably 10 to 90% by mass, more preferably 15 to 70% by mass, even more preferably 20 to 65% by mass, for example, 30 to 65% by mass. It may be mass %. When the ratio is equal to or higher than the lower limit, the structure of the film adhesive becomes more stable. When the ratio is below the upper limit, it becomes easy to increase the amount of components other than the acrylic resin (a), such as the epoxy compound (b1) and the phosphorus antioxidant (z), and The effects of using components other than resin (a) can be obtained more easily.

<Epoxy compound (b1)>
The epoxy compound (b1) may be either a resin component or a non-resin component.
Examples of the epoxy compound (b1) include known ones, such as polyfunctional epoxy resins, biphenyl compounds, bisphenol A diglycidyl ether and hydrogenated products thereof, orthocresol novolak epoxy resins, dicyclopentadiene type epoxy resins, Examples include epoxy compounds having two or more functionalities, such as biphenyl type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenylene skeleton type epoxy resin, and triazine type alicyclic epoxy compound.

As the epoxy compound (b1), an epoxy compound having an unsaturated hydrocarbon group may be used. An epoxy compound having an unsaturated hydrocarbon group has higher compatibility with the acrylic resin (a) than an epoxy compound having no unsaturated hydrocarbon group. Therefore, by using the epoxy compound (b1) having an unsaturated hydrocarbon group, the reliability of the package obtained using the film adhesive is improved.

Examples of the epoxy compound (b1) having an unsaturated hydrocarbon group include a compound having a structure in which a part of the epoxy group of a polyfunctional epoxy compound is converted into a group having an unsaturated hydrocarbon group. Such a compound can be obtained, for example, by adding (meth)acrylic acid or a derivative thereof to an epoxy group.

Examples of the epoxy compound (b1) having an unsaturated hydrocarbon group include compounds in which a group having an unsaturated hydrocarbon group is directly bonded to an aromatic ring constituting the epoxy compound.
The unsaturated hydrocarbon group is a polymerizable unsaturated group, and specific examples thereof include ethenyl group (vinyl group), 2-propenyl group (allyl group), (meth)acryloyl group, (meth) Examples include an acrylamide group, and an acryloyl group is preferred.

The number average molecular weight of the epoxy compound (b1) (in other words, the epoxy resin (b1)) that is the resin component is not particularly limited, but it depends on the curability of the film adhesive and the strength and heat resistance of the cured product of the film adhesive. From this point of view, it is preferably 300 to 30,000, more preferably 400 to 10,000, and particularly preferably 500 to 3,000.
The epoxy equivalent of the epoxy compound (b1) is preferably 100 to 1000 g/eq, more preferably 120 to 600 g/eq.

The adhesive composition and the film adhesive may contain only one type of epoxy compound (b1), or two or more types, and in the case of two or more types, the combination and ratio thereof can be arbitrarily selected.

The epoxy compound (b1) is preferably an aliphatic compound. That is, the film adhesive preferably contains an aliphatic epoxy compound.
As used herein, the term "aliphatic compound" means a compound having an aliphatic group and no aromatic group. Further, the "aliphatic group" includes a chain aliphatic group and an aliphatic cyclic group (also known as an alicyclic group). Moreover, the "aromatic group" includes an aromatic hydrocarbon group and an aromatic heterocyclic group.
When the adhesive composition and the film adhesive contain an aliphatic compound as the epoxy compound (b1), the effect of suppressing coloring of the film adhesive after heating (e.g., heating at 260°C) is suppressed. By containing only aliphatic compounds (in other words, not containing aromatic compounds), the above-mentioned effect of suppressing coloring becomes significantly higher.

The epoxy compound (b1) is selected from the group consisting of triple bonds between carbon atoms (C≡C), double bonds between carbon atoms (C=C), cyano groups (-C≡N) and aromatic groups. It is preferable not to have one or more types.
When the adhesive composition and the film adhesive contain an epoxy compound (b1) that does not have these bonds or groups, the film adhesive can be colored after heating (e.g., heating at 260°C). By containing only those that do not have these bonds or groups (in other words, not containing those that have these bonds or groups), the above-mentioned coloring suppressing effect becomes significantly higher.

The epoxy compound (b1) is an aliphatic compound, and is composed of a triple bond between carbon atoms (C≡C), a double bond between carbon atoms (C=C), and a cyano group (-C≡N). It is preferable not to have one or more selected from the group consisting of: That is, the film adhesive contains an aliphatic epoxy compound that does not have one or more selected from the group consisting of triple bonds between carbon atoms, double bonds between carbon atoms, and cyano groups. It is preferable.
When the adhesive composition and the film adhesive contain an aliphatic compound that does not have these bonds or groups as the epoxy compound (b1), the film adhesive can be heated (e.g., heated at 260°C). By containing only aliphatic compounds that do not have these bonds or groups (in other words, not containing aliphatic compounds that have these bonds or groups), the effect of suppressing the subsequent coloring becomes higher. The inhibitory effect of

In the adhesive composition and the film adhesive, the content of the epoxy compound (b1) is preferably 5 to 500 parts by mass based on 100 parts by mass of the acrylic resin (a), for example, It may be any one of 5 to 200 parts by weight, 5 to 150 parts by weight, 5 to 110 parts by weight, and 5 to 100 parts by weight. When the content of the epoxy compound (b1) is within such a range, it becomes easier to adjust the adhesive force between the film adhesive and the resin film or dicing sheet described below.

<Phosphorous antioxidant (z)>
Since the film adhesive contains the phosphorus antioxidant (z), coloring before and after heating is further suppressed.
The phosphorus-based antioxidant (z) is not particularly limited as long as it has a phosphorus atom as a constituent atom and has an antioxidant effect.
Examples of the phosphorus-based antioxidant (z) include compounds in which the oxidation number of phosphorus is 3.

The adhesive composition and film adhesive may contain only one kind of phosphorus antioxidant (z), or two or more kinds, and when they are two or more kinds, the combination and ratio thereof can be arbitrarily determined. You can choose.

The phosphorus antioxidant (z) is preferably an aliphatic compound.
When the adhesive composition and the film adhesive contain an aliphatic compound as the phosphorus antioxidant (z), coloring of the film adhesive after heating (e.g., heating at 260°C) is reduced. The suppressing effect becomes higher, and by containing only aliphatic compounds (in other words, not containing aromatic compounds), the above-mentioned coloring suppressing effect becomes significantly higher.

The phosphorus antioxidant (z) is a group consisting of a triple bond between carbon atoms (C≡C), a double bond between carbon atoms (C=C), a cyano group (-C≡N), and an aromatic group. It is preferable not to have one or more selected from.
When the adhesive composition and the film adhesive contain a phosphorus antioxidant (z) that does not have these bonds or groups, the film adhesive can be heated (e.g., heated at 260°C). By containing only those that do not have these bonds or groups (in other words, not containing those that have these bonds or groups), the effect of suppressing the coloring mentioned above becomes remarkable. It gets expensive.

The phosphorus antioxidant (z) is an aliphatic compound, and contains a triple bond between carbon atoms (C≡C), a double bond between carbon atoms (C=C), and a cyano group (-C≡ It is preferable not to have one or more selected from the group consisting of N).
When the adhesive composition and the film adhesive contain an aliphatic compound that does not have these bonds or groups as the phosphorus antioxidant (z), the film adhesive can be heated (e.g., at 260°C). By containing only aliphatic compounds that do not have these bonds or groups (in other words, not containing aliphatic compounds that have these bonds or groups), the effect of suppressing coloring after heating is higher, The above-mentioned effect of suppressing coloring is significantly enhanced.

The phosphorus-based antioxidant (z) is preferably a phosphite ester because it stably exhibits an antioxidant effect.
Among these, the phosphorus antioxidant (z) is more preferably an aliphatic phosphite, and even more preferably an aliphatic phosphite trialkyl ester.
That is, the film adhesive preferably contains a phosphite as an antioxidant, more preferably contains an aliphatic phosphite, and preferably contains an aliphatic phosphite trialkyl ester. It is even more preferable to contain it.

Examples of aliphatic phosphite trialkyl esters include triethyl phosphite ((C ₂ H ₅ O) ₃ P), tris(2-ethylhexyl) phosphite ((CH ₃ CH ₂ CH ₂ CH ₂ CH(CH ₂ CH ₃ )CH ₂ O) ₃ P), tridecyl phosphite ((C ₁₀ H ₂₁ O) ₃ P), trilauryl phosphite ((C ₁₂ H ₂₅ O) ₃ P), tris(tridecyl) phosphite ((C ₁₃ H ₂₇ O) ₃ P), tristearylphosphite ((C ₁₈ H ₃₇ O) ₃ P), bis(decyl)pentaerythritol diphosphite (C ₁₀ H ₂₁ OP(OCH ₂ ) ₂ C( _CH2O ) _2POC10H21 ), _bis (tridecyl)pentaerythritol diphosphite ( _{C13H27OP ( OCH2 ) 2C} ( _CH2O ) _{2POC13H27 )} , _{distearylpentaerythritol} diphosphite Phite (C ₁₈ H ₃₇ OP(OCH ₂ ) ₂ C(CH ₂ O) ₂ POC ₁₈ H ₃₇ ), hydrogenated bisphenol A-pentaerythritol phosphite polymer (formula “-(OC ₆ H ₁₂ C(CH ₃ ) ₂ C ₆ H ₁₂ OP(OCH ₂ ) ₂ C(CH ₂ O) ₂ P)-” and the like.

In the adhesive composition, the ratio of the content of the phosphorus antioxidant (z) to the total content of all components other than the solvent (i.e., the ratio of the phosphorus antioxidant (z) to the total mass of the film adhesive in the adhesive composition) The content ratio of the antioxidant (z) is preferably 0.1 to 5% by mass, more preferably 0.2 to 3% by mass, and 0.3 to 1.5% by mass. % is more preferable. When the ratio is equal to or higher than the lower limit, the effect of using the phosphorus antioxidant (z) can be more significantly obtained. When the ratio is equal to or less than the upper limit, excessive use of the phosphorus antioxidant (z) is suppressed.

In order to improve various physical properties of the film adhesive, in addition to the acrylic resin (a), the epoxy compound (b1), and the phosphorus antioxidant (z), any of these may be added as necessary. It may also contain other components that do not fall under this category.
Other components contained in the film adhesive include, for example, a phenol resin (b2), a curing accelerator (c), a filler (d), a coupling agent (e), a crosslinking agent (f), and an energy beam. Curable resin (g), photopolymerization initiator (h), antioxidant (y) other than phosphorus antioxidant (z) (herein abbreviated as "other antioxidant (y)") ), thermoplastic resins (x) other than acrylic resins (a) (sometimes abbreviated as "thermoplastic resins (x)" in this specification), general-purpose additives (i), etc. can be mentioned.

<Phenol resin (b2)>
The phenol resin (b2) functions as a thermosetting agent for the epoxy compound (b1).
In this embodiment, when the epoxy compound (b1) and the phenol resin (b2) are used together, the combination functions as an epoxy thermosetting resin. In this embodiment, such an epoxy thermosetting resin may be referred to as "epoxy thermosetting resin (b)."

The phenol resin (b2) may have two or more phenolic hydroxyl groups in one molecule as a functional group capable of reacting with an epoxy group.

Examples of the phenolic resin (b2) include polyfunctional phenolic resins, novolac-type phenolic resins, dicyclopentadiene-type phenolic resins, aralkyl-type phenolic resins, and the like.

The phenol resin (b2) may have an unsaturated hydrocarbon group.
Other phenolic resins (b2) having an unsaturated hydrocarbon group include, for example, compounds having a structure in which a part of the hydroxyl groups of the phenol resin are substituted with groups having an unsaturated hydrocarbon group, and aromatic rings of the phenol resin. Examples include compounds having a structure in which a group having an unsaturated hydrocarbon group is directly bonded.
The unsaturated hydrocarbon group in the phenol resin (b2) is the same as the unsaturated hydrocarbon group in the above-mentioned epoxy compound having an unsaturated hydrocarbon group.

The phenol resin (b2) preferably has a high softening point or glass transition temperature, since it becomes easy to adjust the adhesive strength of the film adhesive.

The number average molecular weight of the phenol resin (b2) is preferably 300 to 30,000, more preferably 400 to 10,000, particularly preferably 500 to 3,000.

The adhesive composition and the film adhesive may contain only one type of phenolic resin (b2), or two or more types. When there are two or more types, the combination and ratio thereof can be arbitrarily selected.

When using the phenolic resin (b2), in the adhesive composition, the ratio of the content of the phenolic resin (b2) to the total content of all components other than the solvent (i.e., the ratio of the content of the phenolic resin (b2) in the adhesive composition The ratio of the content of phenolic resin (b2) to the total mass of is not particularly limited, but is preferably 10% by mass or less, more preferably 7.5% by mass or less, and 5% by mass or less. It is more preferable that When the ratio is below the upper limit, the effect of suppressing coloring of the film adhesive after heating (for example, heating at 260° C.) becomes higher.
That is, as a preferable example of the film adhesive containing the phenolic resin (b2), the ratio of the content of the phenolic resin (b2) to the total mass of the film adhesive in the film adhesive is , 10% by mass or less.

When using the phenolic resin (b2), in the adhesive composition, the ratio of the content of the phenolic resin (b2) to the total content of all components other than the solvent (i.e., the ratio of the content of the phenolic resin (b2) in the adhesive composition The lower limit of the ratio of the content of phenolic resin (b2) to the total mass of is not particularly limited.
For example, the ratio is preferably 0.5% by mass or more in order to obtain more remarkable effects by using the phenol resin (b2).

When using the phenol resin (b2), the ratio can be adjusted as appropriate within a range set by arbitrarily combining the above-mentioned lower limit and any upper limit. For example, in one embodiment, the proportion is preferably 0.5 to 10% by weight, more preferably 0.5 to 7.5% by weight, and more preferably 0.5 to 5% by weight. is even more preferable.

When using the phenolic resin (b2), the content of the phenolic resin (b2) in the adhesive composition and the film adhesive is, for example, 3 to 30 parts by mass per 100 parts by mass of the epoxy compound (b1). Parts by mass, 3 to 25 parts by mass, and 3 to 20 parts by mass, or 5 to 30 parts by mass, 10 to 30 parts by mass, and 15 to 30 parts by mass. The amount may be either 5 to 25 parts by mass or 10 to 20 parts by mass.

<Curing accelerator (c)>
The curing accelerator (c) is a component for adjusting the curing speed of the adhesive composition and film adhesive.
Preferred curing accelerators (c) include, for example, tertiary amines such as triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, and tris(dimethylaminomethyl)phenol; 2-methylimidazole, 2-phenylimidazole; , 2-phenyl-4-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, and other imidazoles (where one or more hydrogen atoms are other than hydrogen atoms) (imidazole substituted with a group of Examples include tetraphenylboron salts such as tetraphenylborate; clathrate compounds having the imidazoles mentioned above as a guest compound, and the like.

The curing accelerator (c) contained in the adhesive composition and the film adhesive may be one type or two or more types, and when there are two or more types, the combination and ratio thereof can be arbitrarily selected. .

When using the curing accelerator (c), the content of the curing accelerator (c) in the adhesive composition and film adhesive is 100 parts by mass of the total content of the epoxy compound (b1) and the phenolic resin (b2). The amount is preferably 0.01 to 7 parts by weight, more preferably 0.1 to 4 parts by weight. When the content of the curing accelerator (c) is at least the lower limit, the effect of using the curing accelerator (c) can be more significantly obtained. By setting the content of the curing accelerator (c) below the above-mentioned upper limit, for example, the highly polar curing accelerator (c) will not interact with the adherend in the film adhesive under high temperature and high humidity conditions. The effect of suppressing migration to the adhesive interface side and segregation becomes higher, and the reliability of the package obtained using the film adhesive is further improved. In addition, when the phenol resin (b2) is not used, the total content of the epoxy compound (b1) and the phenol resin (b2) means the content of the epoxy compound (b1).

<Filler (d)>
By containing the filler (d), the film adhesive can easily adjust its thermal expansion coefficient, and by optimizing this thermal expansion coefficient for the object to which the film adhesive is attached, the film adhesive can be easily adjusted. The reliability of packages obtained using adhesives is further improved. Moreover, when the film adhesive contains the filler (d), the moisture absorption rate of the cured product of the film adhesive can be reduced and the heat dissipation property can be improved.

The filler (d) may be either an organic filler or an inorganic filler, but is preferably an inorganic filler.
Preferred inorganic fillers include, for example, powders of silica, alumina, talc, calcium carbonate, titanium white, red iron, silicon carbide, boron nitride, etc.; beads formed by spheroidizing these inorganic fillers; surface modification of these inorganic fillers. products; single crystal fibers of these inorganic fillers; glass fibers and the like.
Among these, the inorganic filler is preferably silica or a surface-modified product thereof.

The average particle diameter of the filler (d) is not particularly limited, but is preferably 10 to 100 nm, more preferably 10 to 80 nm, and even more preferably 10 to 60 nm. When the average particle diameter of the filler (d) is below the upper limit, turbidity of the film adhesive is highly suppressed, and the straight line of the film adhesive before heating with light (400 to 800 nm) is suppressed. The transmittance and in-line transmittance after heating are improved, and as a result, the image recognition properties of the film adhesive before and after heating are improved. When the average particle diameter of the filler (d) is equal to or larger than the lower limit, the effect of using the filler (d) can be more significantly obtained.
In addition, in this specification, the "average particle diameter" means the value of the particle diameter (D ₅₀ ) at 50% of the integrated value in the particle size distribution curve determined by laser diffraction scattering method, unless otherwise specified. .

The adhesive composition and the film adhesive may contain only one type of filler (d), or two or more types, and when they are two or more types, the combination and ratio thereof can be arbitrarily selected.

When using the filler (d), in the adhesive composition, the ratio of the content of the filler (d) to the total content of all components other than the solvent (i.e., the ratio of the content of the filler (d) to the total content of all components other than the solvent) The content ratio of the filler (d) to the total mass is preferably 7.5 to 50% by mass, more preferably 10 to 45% by mass, and 12.5 to 40% by mass. It is particularly preferable that there be. When the content of the filler (d) is within this range, the above-mentioned coefficient of thermal expansion can be adjusted more easily.

<Coupling agent (e)>
By containing the coupling agent (e), the film adhesive improves adhesiveness and adhesion to the adherend. Further, since the film adhesive contains the coupling agent (e), the cured product thereof has improved water resistance without impairing heat resistance. The coupling agent (e) has a functional group capable of reacting with an inorganic compound or an organic compound.

The coupling agent (e) is preferably a compound having a functional group capable of reacting with the functional group of the acrylic resin (a), the epoxy thermosetting resin (b), etc., and is a silane coupling agent. It is more preferable.
Preferred examples of the silane coupling agent include 3-glycidyloxypropyltrimethoxysilane, 3-glycidyloxypropylmethyldiethoxysilane, 3-glycidyloxypropyltriethoxysilane, 3-glycidyloxymethyldiethoxysilane, and 2-glycidyloxypropyltriethoxysilane. (3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-(2-aminoethylamino)propyltrimethoxysilane, 3-(2-amino ethylamino)propylmethyldiethoxysilane, 3-(phenylamino)propyltrimethoxysilane, 3-anilinopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylmethyl Examples include dimethoxysilane, bis(3-triethoxysilylpropyl)tetrasulfane, methyltrimethoxysilane, methyltriethoxysilane, vinyltrimethoxysilane, vinyltriacetoxysilane, imidazolesilane, oligomer type or polymer type organosiloxane, etc. .

The coupling agent (e) is preferably an aliphatic compound.
When the adhesive composition and the film adhesive contain an aliphatic compound as the coupling agent (e), the effect of suppressing coloring of the film adhesive after heating (for example, heating at 260° C.) By containing only aliphatic compounds (in other words, not containing aromatic compounds), the above-mentioned effect of suppressing coloring becomes significantly higher.

The coupling agent (e) is selected from the group consisting of triple bonds between carbon atoms (C≡C), double bonds between carbon atoms (C=C), cyano groups (-C≡N), and aromatic groups. It is preferable not to have one or more types.
When the adhesive composition and the film adhesive contain a coupling agent (e) that does not have any of these bonds or groups, the adhesive composition and the film adhesive can be heated (e.g., heated at 260°C). The effect of suppressing coloring becomes higher, and by containing only those that do not have these bonds or groups (in other words, not containing those that have these bonds or groups), the above-mentioned effect of suppressing coloring becomes significantly higher. .

The coupling agent (e) is an aliphatic compound, and has a triple bond between carbon atoms (C≡C), a double bond between carbon atoms (C=C), and a cyano group (-C≡N). It is preferable not to have one or more selected from the group consisting of:
When the adhesive composition and the film adhesive contain an aliphatic compound that does not have these bonds or groups as the coupling agent (e), heating of the film adhesive (for example, heating at 260° C. ) By containing only aliphatic compounds that do not have these bonds or groups (in other words, not containing aliphatic compounds that have these bonds or groups), the above-mentioned The effect of suppressing coloring is significantly increased.

Among the coupling agents (e), more specifically examples of aliphatic compounds (aliphatic coupling agents) include 3-glycidyloxypropyltrimethoxysilane, 3-glycidyloxypropylmethyldiethoxysilane, 3-glycidyloxypropyltriethoxysilane, 3-glycidyloxymethyldiethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-(2-aminoethylamino)propyltrimethoxysilane, 3-(2-aminoethylamino)propylmethyldiethoxysilane, 3-ureidopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylmethyl Examples include dimethoxysilane, bis(3-triethoxysilylpropyl)tetrasulfane, methyltrimethoxysilane, methyltriethoxysilane, vinyltrimethoxysilane, vinyltriacetoxysilane, and oligomeric or polymeric organosiloxanes.

The adhesive composition and the film adhesive may contain only one type of coupling agent (e), or two or more types, and in the case of two or more types, the combination and ratio thereof can be arbitrarily selected. .

When using the coupling agent (e), the content of the coupling agent (e) in the adhesive composition and film adhesive is the total amount of the acrylic resin (a) and the epoxy thermosetting resin (b). The content is preferably 0.03 to 20 parts by weight, more preferably 0.05 to 10 parts by weight, and particularly preferably 0.1 to 5 parts by weight. When the content of the coupling agent (e) is at least the lower limit, the dispersibility of the filler (d) in the resin is improved, the adhesiveness of the film adhesive to the adherend is improved, etc. , the effect of using the coupling agent (e) is more noticeable. When the content of the coupling agent (e) is less than or equal to the upper limit, the generation of outgas is further suppressed.

<Crosslinking agent (f)>
When using an acrylic resin (a) having a functional group such as a vinyl group, (meth)acryloyl group, amino group, hydroxyl group, carboxy group, or isocyanate group that can bond with the other compounds mentioned above, the adhesive composition The product and the film adhesive may contain a crosslinking agent (f) for bonding the functional group with another compound and crosslinking it. By crosslinking using the crosslinking agent (f), the initial adhesive force and cohesive force of the film adhesive can be adjusted.

Examples of the crosslinking agent (f) include organic polyvalent isocyanate compounds, organic polyvalent imine compounds, metal chelate crosslinking agents (crosslinking agents having a metal chelate structure), aziridine crosslinking agents (crosslinking agents having an aziridinyl group), etc. can be mentioned.

Examples of the organic polyvalent isocyanate compounds include aromatic polyvalent isocyanate compounds, aliphatic polyvalent isocyanate compounds, and alicyclic polyvalent isocyanate compounds (hereinafter, these compounds are collectively referred to as "aromatic polyvalent isocyanate compounds, etc.") trimer, isocyanurate, and adduct of the aromatic polyvalent isocyanate compound, etc.; terminal isocyanate urethane prepolymer obtained by reacting the aromatic polyvalent isocyanate compound, etc. with a polyol compound etc. The "adduct" is an adduct of the aromatic polyvalent isocyanate compound, aliphatic polyvalent isocyanate compound, or alicyclic polyvalent isocyanate compound and a lower compound such as ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane, or castor oil. Molecularly refers to a reactant with an active hydrogen-containing compound. Examples of the adducts include xylylene diisocyanate adducts of trimethylolpropane, isophorone diisocyanate adducts of trimethylolpropane, tolylene diisocyanate adducts of trimethylolpropane, and hexamethylene diisocyanate adducts of trimethylolpropane, as described below. etc. Further, the term "terminated isocyanate urethane prepolymer" means a prepolymer having a urethane bond and an isocyanate group at the end of the molecule.

More specifically, the organic polyvalent isocyanate compound includes, for example, 2,4-tolylene diisocyanate; 2,6-tolylene diisocyanate; 1,3-xylylene diisocyanate; 1,4-xylylene diisocyanate; diphenylmethane- 4,4'-diisocyanate; diphenylmethane-2,4'-diisocyanate; 3-methyldiphenylmethane diisocyanate; hexamethylene diisocyanate; isophorone diisocyanate; dicyclohexylmethane-4,4'-diisocyanate; dicyclohexylmethane-2,4'-diisocyanate; Compounds in which one or more of tolylene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, and xylylene diisocyanate are added to all or some of the hydroxyl groups of a polyol such as methylolpropane; examples include lysine diisocyanate.

Examples of the organic polyvalent imine compound include N,N'-diphenylmethane-4,4'-bis(1-aziridinecarboxamide), trimethylolpropane-tri-β-aziridinylpropionate, and tetramethylolmethane. -tri-β-aziridinylpropionate, N,N'-toluene-2,4-bis(1-aziridinecarboxamide)triethylenemelamine, and the like.

When using an organic polyvalent isocyanate compound as the crosslinking agent (f), it is preferable to use a hydroxyl group-containing polymer as the acrylic resin (a). When the crosslinking agent (f) has an isocyanate group and the acrylic resin (a) has a hydroxyl group, the crosslinked structure can be easily created in the film adhesive by the reaction between the crosslinking agent (f) and the acrylic resin (a). It can be introduced to

The crosslinking agent (f) is preferably an aliphatic compound.
When the adhesive composition and the film adhesive contain an aliphatic compound as the crosslinking agent (f), the effect of suppressing coloring of the film adhesive after heating (e.g., heating at 260°C) can be improved. By containing only aliphatic compounds (in other words, not containing aromatic compounds), the above-mentioned effect of suppressing coloring becomes significantly higher.

The crosslinking agent (f) is selected from the group consisting of triple bonds between carbon atoms (C≡C), double bonds between carbon atoms (C=C), cyano groups (-C≡N) and aromatic groups. It is preferable not to have one or more types.
When the adhesive composition and the film adhesive contain a crosslinking agent (f) that does not have these bonds or groups, the film adhesive can be colored after heating (e.g., heating at 260°C). By containing only those that do not have these bonds or groups (in other words, not containing those that have these bonds or groups), the above-mentioned coloring suppressing effect becomes significantly higher.

The crosslinking agent (f) is an aliphatic compound, and is formed from a triple bond between carbon atoms (C≡C), a double bond between carbon atoms (C=C), and a cyano group (-C≡N). It is preferable not to have one or more selected from the group consisting of:
When the adhesive composition and the film adhesive contain an aliphatic compound that does not have these bonds or groups as the crosslinking agent (f), heating of the film adhesive (e.g., heating at 260° C.) By containing only aliphatic compounds that do not have these bonds or groups (in other words, not containing aliphatic compounds that have these bonds or groups), the effect of suppressing the subsequent coloring becomes higher. The inhibitory effect of

The crosslinking agent (f) is an aliphatic organic polyvalent isocyanate compound (aliphatic polyisocyanate crosslinking agent) in that it has a particularly high effect of suppressing the above-mentioned coloration and has excellent properties as a crosslinking agent. is preferred.
More specifically, the aliphatic polyisocyanate crosslinking agent includes, for example, 2,4-tolylene diisocyanate; 2,6-tolylene diisocyanate; hexamethylene diisocyanate; isophorone diisocyanate; dicyclohexylmethane-4,4'- Diisocyanate; Dicyclohexylmethane-2,4'-diisocyanate; A compound in which one or more of tolylene diisocyanate, isophorone diisocyanate, and hexamethylene diisocyanate is added to all or some of the hydroxyl groups of a polyol such as trimethylolpropane. ; Examples include lysine diisocyanate.

When focusing on the acrylic resin (a) and the crosslinking agent (f), the film adhesive has a particularly high effect of suppressing the above-mentioned coloring, and has excellent properties. It is preferable that the acrylic resin (a) contains the aliphatic polyisocyanate crosslinking agent and has a functional group capable of bonding with the aliphatic polyisocyanate crosslinking agent.

The adhesive composition and the film adhesive may contain only one type of crosslinking agent (f), or two or more types. When there are two or more types, the combination and ratio thereof can be arbitrarily selected.

When using the crosslinking agent (f), the content of the crosslinking agent (f) in the adhesive composition and film adhesive is 0.3 to 100 parts by mass of the acrylic resin (a). The amount is preferably 12 parts by weight, more preferably 0.3 to 3.5 parts by weight, and even more preferably 0.3 to 2 parts by weight. When the content of the crosslinking agent (f) is at least the lower limit, the effect of using the crosslinking agent (f) can be more significantly obtained. Moreover, excessive use of the crosslinking agent (f) is suppressed because the content of the crosslinking agent (f) is equal to or less than the upper limit value.

<Energy ray curable resin (g)>
The adhesive composition and the film adhesive may contain an energy ray curable resin (g). Since the film adhesive contains the energy ray curable resin (g), its properties can be changed by irradiation with energy rays.

As used herein, the term "energy ray" refers to electromagnetic waves or charged particle beams that have energy quanta, examples of which include ultraviolet rays, radiation, electron beams, and the like.
The ultraviolet rays can be irradiated using, for example, a high-pressure mercury lamp, a fusion lamp, a xenon lamp, a black light, an LED lamp, or the like as an ultraviolet source. The electron beam can be generated by an electron beam accelerator or the like.
In this specification, "energy ray curable" means a property that hardens by irradiation with energy rays, and "non-energy ray curable" means a property that does not harden even when irradiated with energy rays. do.

The energy ray curable resin (g) is obtained by polymerizing (curing) an energy ray curable compound.
Examples of the energy ray-curable compound include compounds having at least one polymerizable double bond in the molecule, and acrylate compounds having a (meth)acryloyl group are preferred.

Examples of the acrylate compounds include trimethylolpropane tri(meth)acrylate, tetramethylolmethanetetra(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, and dipentaerythritol monohydroxypenta( Chain aliphatic skeleton-containing (meth)acrylates such as meth)acrylate, dipentaerythritol hexa(meth)acrylate, 1,4-butylene glycol di(meth)acrylate, and 1,6-hexanediol di(meth)acrylate; Cycloaliphatic skeleton-containing (meth)acrylates such as cyclopentanyl di(meth)acrylate; polyalkylene glycol (meth)acrylates such as polyethylene glycol di(meth)acrylate; oligoester (meth)acrylates; urethane (meth)acrylate oligomers ; epoxy-modified (meth)acrylates; polyether (meth)acrylates other than the polyalkylene glycol (meth)acrylates; itaconic acid oligomers and the like.

The weight average molecular weight of the energy ray curable resin (g) is preferably 100 to 30,000, more preferably 300 to 10,000.

The adhesive composition may contain only one kind of energy ray-curable resin (g), or two or more kinds. When there are two or more kinds, the combination and ratio thereof can be arbitrarily selected.

When using the energy ray curable resin (g), the content ratio of the energy ray curable resin (g) to the total mass of the adhesive composition in the adhesive composition must be 1 to 95% by mass. The content is preferably from 5 to 90% by mass, more preferably from 10 to 85% by mass.

<Photopolymerization initiator (h)>
When the adhesive composition and film adhesive contain an energy ray curable resin (g), a photopolymerization initiator (h) is added in order to efficiently advance the polymerization reaction of the energy ray curable resin (g). May contain.

Examples of the photopolymerization initiator (h) include benzoin compounds such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzoin benzoic acid, benzoin methyl benzoate, and benzoin dimethyl ketal; acetophenone; Acetophenone compounds such as 2-hydroxy-2-methyl-1-phenyl-propan-1-one, 2,2-dimethoxy-1,2-diphenylethan-1-one; bis(2,4,6-trimethylbenzoyl) Acylphosphine oxide compounds such as phenylphosphine oxide and 2,4,6-trimethylbenzoyldiphenylphosphine oxide; Sulfide compounds such as benzylphenyl sulfide and tetramethylthiuram monosulfide; α-ketols such as 1-hydroxycyclohexylphenyl ketone Compounds; azo compounds such as azobisisobutyronitrile; titanocene compounds such as titanocene; thioxanthone compounds such as thioxanthone; peroxide compounds; diketone compounds such as diacetyl; benzyl; dibenzyl; benzophenone; 2,4-diethylthioxanthone; 1, Examples include 2-diphenylmethane; 2-hydroxy-2-methyl-1-[4-(1-methylvinyl)phenyl]propanone; quinone compounds such as 1-chloroanthraquinone and 2-chloroanthraquinone;
Examples of the photopolymerization initiator (h) include photosensitizers such as amines.

The photopolymerization initiator (h) is preferably an aliphatic compound.
By containing an aliphatic compound as a photopolymerization initiator (h) in the adhesive composition and film adhesive, coloring of the film adhesive after heating (for example, heating at 260°C) is suppressed. The effect becomes higher, and by containing only an aliphatic compound (in other words, not containing an aromatic compound), the above-mentioned effect of suppressing coloring becomes significantly higher.

The photopolymerization initiator (h) is selected from the group consisting of triple bonds between carbon atoms (C≡C), double bonds between carbon atoms (C=C), cyano groups (-C≡N), and aromatic groups. It is preferable not to have one or more selected types.
When the adhesive composition and film adhesive contain a photopolymerization initiator (h) that does not have these bonds or groups, after heating the film adhesive (for example, heating at 260 ° C.) By containing only those that do not have these bonds or groups (in other words, not containing those that have these bonds or groups), the above-mentioned coloring suppressing effect is significantly higher. Become.

The photopolymerization initiator (h) is an aliphatic compound, and contains a triple bond between carbon atoms (C≡C), a double bond between carbon atoms (C=C), and a cyano group (-C≡N ) It is preferable not to have one or more selected from the group consisting of:
When the adhesive composition and the film adhesive contain an aliphatic compound that does not have these bonds or groups as a photopolymerization initiator (h), the film adhesive can be heated (e.g., at 260°C). By containing only aliphatic compounds that do not have these bonds or groups (in other words, not containing aliphatic compounds that have these bonds or groups), the above-mentioned The effect of suppressing coloring is significantly increased.

Among the photopolymerization initiators (h), more specifically, as aliphatic compounds (aliphatic photopolymerization initiators), for example, acylphosphine oxide compounds; sulfide compounds such as tetramethylthiuram monosulfide; Examples include azo compounds such as bisisobutyronitrile; peroxide compounds; diketone compounds such as diacetyl; photosensitizers such as amines.
Among the compounds exemplified here, they are aliphatic compounds, and have triple bonds between carbon atoms (C≡C), double bonds between carbon atoms (C=C), and cyano groups (-C≡N). Examples of the photopolymerization initiator (h) that does not contain one or more selected from the group consisting of: compounds other than azobisisobutyronitrile;

The adhesive composition and the film adhesive may contain only one kind of photopolymerization initiator (h), or two or more kinds, and when there are two or more kinds, the combination and ratio thereof can be selected arbitrarily. can.

When using a photopolymerization initiator (h), in the adhesive composition, the content of the photopolymerization initiator (h) is 0.1 with respect to 100 parts by mass of the energy ray curable resin (g). It is preferably from 1 to 20 parts by weight, more preferably from 1 to 10 parts by weight, and particularly preferably from 2 to 5 parts by weight.

<Other antioxidants (y)>
The adhesive composition and film adhesive may contain the other antioxidant (y) as long as the effects of the present invention are not impaired.
The other antioxidant (y) is not particularly limited as long as it is an antioxidant other than the phosphorous antioxidant (z), and may be either an organic compound or an inorganic compound.

The adhesive composition and the film adhesive may contain only one kind of other antioxidant (y), or two or more kinds, and when they are two or more kinds, the combination and ratio thereof can be arbitrarily selected. You can choose.

When using another antioxidant (y), in the adhesive composition and film adhesive, the content of the other antioxidant (y) is 100 parts by mass of the phosphorus antioxidant (z). The amount is preferably 10 parts by mass or less, more preferably 5 parts by mass or less, and even more preferably 1 part by mass or less. When the content of the other antioxidant (y) is at most the upper limit, coloring of the film adhesive before and after heating is further suppressed.

It is preferable that the adhesive composition and film adhesive do not contain other antioxidants (y).

<Thermoplastic resin (x)>
The adhesive composition and film adhesive may contain the thermoplastic resin (x) to the extent that the effects of the present invention are not impaired.
By using the thermoplastic resin (x), for example, when picking up the chip, it becomes easier to separate the chip with the film adhesive from the dicing sheet, which will be described later, or the film can be applied to the uneven surface of the adherend. This makes it easier for the film-like adhesive to follow, and the generation of voids and the like between the adherend and the film-like adhesive may be further suppressed.

The thermoplastic resin (x) is not particularly limited as long as it is a thermoplastic resin other than the acrylic resin (a).
Examples of the thermoplastic resin include polyester, polyurethane, phenoxy resin, polybutene, polybutadiene, polystyrene, and the like.

The weight average molecular weight of the thermoplastic resin (x) is preferably from 1,000 to 100,000, more preferably from 3,000 to 80,000.

The glass transition temperature (Tg) of the thermoplastic resin (x) is preferably -30 to 150°C, more preferably -20 to 120°C.

The adhesive composition and the film adhesive may contain only one type of thermoplastic resin (x), or two or more types, and in the case of two or more types, the combination and ratio thereof can be arbitrarily selected. .

When using a thermoplastic resin (x), the content of the thermoplastic resin (x) in the adhesive composition and film adhesive is 10 parts by mass per 100 parts by mass of the acrylic resin (a). It is preferably at most 5 parts by weight, more preferably at most 5 parts by weight, even more preferably at most 1 part by weight. When the content of the thermoplastic resin (x) is equal to or less than the upper limit value, the effect of using the acrylic resin (a) can be more significantly obtained.

It is preferable that the adhesive composition and the film adhesive do not contain the thermoplastic resin (x).

<General purpose additive (i)>
The general-purpose additive (i) may be a known one, can be arbitrarily selected depending on the purpose, and is not particularly limited. Preferred general-purpose additives (I) include, for example, plasticizers, antistatic agents, colorants (dyes, pigments), gettering agents, and the like.

When the general-purpose additive (i) is an organic compound, such general-purpose additive (i) (herein abbreviated as "organic general-purpose additive") is preferably an aliphatic compound. .
By containing an aliphatic compound as an organic general-purpose additive in the adhesive composition and film adhesive, the effect of suppressing coloring after heating the film adhesive (e.g., heating at 260°C) can be improved. By containing only aliphatic compounds (in other words, not containing aromatic compounds), the above-mentioned effect of suppressing coloring becomes significantly higher.

The organic general purpose additive is selected from the group consisting of triple bonds between carbon atoms (C≡C), double bonds between carbon atoms (C=C), cyano groups (-C≡N) and aromatic groups. It is preferable not to have one or more types.
When the adhesive composition and film adhesive contain additives that do not have these bonds or groups as organic general-purpose additives, coloring of the film adhesive after heating (e.g., heating at 260°C) is reduced. The suppressing effect on coloring becomes higher, and by containing only those that do not have these bonds or groups (in other words, not containing those that have these bonds or groups), the above-mentioned coloring suppressing effect becomes significantly higher.

The organic general-purpose additive is an aliphatic compound and consists of a triple bond between carbon atoms (C≡C), a double bond between carbon atoms (C=C), and a cyano group (-C≡N). It is preferable not to have one or more selected from the group.
By containing an aliphatic compound that does not have these bonds or groups as an organic general-purpose additive in the adhesive composition and film adhesive, the film adhesive can be heated (e.g., heated at 260°C). By containing only aliphatic compounds that do not have these bonds or groups (in other words, not containing aliphatic compounds that have these bonds or groups), the above coloring can be suppressed. The suppressive effect becomes significantly higher.

The adhesive composition and the film adhesive may contain only one type of general-purpose additive (i), or two or more types, and in the case of two or more types, the combination and ratio thereof can be arbitrarily selected. .
The content of the general-purpose additive (i) in the adhesive composition and film adhesive is not particularly limited, and may be appropriately selected depending on the purpose.

<Solvent>
It is preferable that the adhesive composition further contains a solvent. An adhesive composition containing a solvent has good handling properties.
The solvent is not particularly limited, but preferable examples include hydrocarbons such as toluene and xylene; alcohols such as methanol, ethanol, 2-propanol, isobutyl alcohol (2-methylpropan-1-ol), and 1-butanol. ; esters such as ethyl acetate; ketones such as acetone and methyl ethyl ketone; ethers such as tetrahydrofuran; and amides (compounds having an amide bond) such as dimethylformamide and N-methylpyrrolidone.
The number of solvents contained in the adhesive composition may be one, or two or more, and when there are two or more, the combination and ratio thereof can be arbitrarily selected.

The solvent contained in the adhesive composition is preferably methyl ethyl ketone or the like, since the components contained in the adhesive composition can be mixed more uniformly.

<<Method for manufacturing adhesive composition>>
The adhesive composition is obtained by blending the constituent components.
The order in which each component is added when blending is not particularly limited, and two or more components may be added at the same time.
When using a solvent, it may be used by mixing the solvent with any component other than the solvent and diluting this component in advance, or by diluting any component other than the solvent in advance. The solvent may be used by mixing it with these ingredients without keeping it in place.

The method of mixing each component at the time of compounding is not particularly limited, and may be any known method, such as mixing by rotating a stirrer or stirring blade; mixing by using a mixer; or mixing by applying ultrasonic waves. You can select it as appropriate.
The temperature and time during addition and mixing of each component are not particularly limited as long as each component does not deteriorate, and may be adjusted as appropriate, but the temperature is preferably 15 to 30°C.

FIG. 1 is a cross-sectional view schematically showing a film adhesive according to an embodiment of the present invention. Note that the figures used in the following explanation may show important parts enlarged for convenience in order to make the features of the present invention easier to understand, and the dimensional ratio of each component may be the same as the actual one. Not necessarily.

The film adhesive 13 shown here includes a first release film 151 on one surface (sometimes referred to as "first surface" in this specification) 13a, and the first surface 13a is different from the first surface 13a. A second release film 152 is provided on the other surface (sometimes referred to as "second surface" in this specification) 13b on the opposite side. Here, reference numeral 109 is given to a laminated sheet configured by laminating the first release film 151, the film adhesive 13, and the second release film 152 in this order in the thickness direction. ing.
Such a film adhesive 13 (laminated sheet 109) is suitable for storage as a roll, for example.

The film adhesive 13 has the above-mentioned light transmittance. For example, at least one of the first surface 13a and the second surface 13b of the film adhesive 13 satisfies the above-mentioned conditions of V ₁ , V ₂ and P concentration reduction rate.
The thickness of the film adhesive 13 is preferably 10 to 40 μm.
The film adhesive 13 can be formed using the above adhesive composition.

Both the first release film 151 and the second release film 152 may be known ones.
The first release film 151 and the second release film 152 may be the same or different from each other, such as having different peeling forces when peeling from the film adhesive 13. Good too.

In the film adhesive 13 shown in FIG. 1, either the first release film 151 or the second release film 152 is removed, and the resulting exposed surface becomes the surface to be applied to the object. Here, examples of the object to be pasted include the above-mentioned chip and the like. In the case of the chip, the surface to which the film adhesive 13 is applied is the circuit forming surface of the chip.

A preferred embodiment of the film-like adhesive is, for example, a film-like adhesive for bonding a circuit-forming surface of a chip and a light-transmitting cover, comprising:
One side of the film-like adhesive before heating at 260°C was analyzed by X-ray photoelectron spectroscopy to measure the phosphorus concentration V ₁ , and the phosphorus concentration V ₁ was measured. Of the film adhesive after heating for 1 minute, the side on which V ₁ was measured was analyzed by X-ray photoelectron spectroscopy, and when the phosphorus concentration V ₂ was measured, it was found that V ₁ was 0.1 atomic. % or more, and the reduction rate of the phosphorus concentration calculated from the V ₁ and V ₂ is 25% or less,
Using the film-like adhesive with a size of 2 mm x 2 mm and a thickness of 20 μm, a copper plate with a size of 30 mm x 30 mm and a thickness of 300 μm, and a silicon chip, , a test piece configured such that one entire surface is attached to the surface of the silicon chip and the other surface is attached to the surface of the copper plate, and the side surfaces of the film adhesive and the silicon chip are aligned. was prepared, and under a temperature condition of 23°C, on the aligned side surface of the test piece, the other side of the film adhesive was applied to both the film adhesive and the silicon chip. A force is applied at a speed of 200 μm/s in a direction parallel to the surface, and the maximum value of the force applied until the film adhesive breaks is determined as the shear strength (N /2mm□), the shear strength is 20N/2mm□ or more.

A preferred embodiment of the film-like adhesive is, for example, a film-like adhesive for bonding a circuit-forming surface of a chip and a light-transmitting cover, comprising:
One side of the film-like adhesive before heating at 260°C was analyzed by X-ray photoelectron spectroscopy to measure the phosphorus concentration V ₁ , and the phosphorus concentration V ₁ was measured. The surface of the film-like adhesive after heating for 1 minute, on which V ₁ was measured, was analyzed by X-ray photoelectron spectroscopy, and when the phosphorus concentration V ₂ was measured, it was found that V ₁ was 0.1 atomic. % or more, and the rate of decrease in the phosphorus concentration calculated from the V ₁ and V ₂ is 25% or less,
The film adhesive contains a phosphorus antioxidant (z),
The phosphorus antioxidant (z) is an aliphatic compound, and one type selected from the group consisting of a triple bond between carbon atoms, a double bond between carbon atoms, and a cyano group. Or one that does not have two or more types.

A preferred embodiment of the film-like adhesive is, for example, a film-like adhesive for bonding a circuit-forming surface of a chip and a light-transmitting cover, comprising:
One side of the film-like adhesive before heating at 260°C was analyzed by X-ray photoelectron spectroscopy to measure the phosphorus concentration V ₁ , and the phosphorus concentration V ₁ was measured. The surface of the film-like adhesive after heating for 1 minute, on which V ₁ was measured, was analyzed by X-ray photoelectron spectroscopy, and when the phosphorus concentration V ₂ was measured, it was found that V ₁ was 0.1 atomic. % or more, and the rate of decrease in the phosphorus concentration calculated from the V ₁ and V ₂ is 25% or less,
The film adhesive contains an epoxy compound (b1),
The epoxy compound (b1) is an aliphatic compound, and one or two selected from the group consisting of a triple bond between carbon atoms, a double bond between carbon atoms, and a cyano group. Examples include those that do not have the above.

A preferred embodiment of the film-like adhesive is, for example, a film-like adhesive for bonding a circuit-forming surface of a chip and a light-transmitting cover, comprising:
One side of the film-like adhesive before heating at 260°C was analyzed by X-ray photoelectron spectroscopy to measure the phosphorus concentration V ₁ , and the phosphorus concentration V ₁ was measured. Of the film adhesive after heating for 1 minute, the side on which V ₁ was measured was analyzed by X-ray photoelectron spectroscopy, and when the phosphorus concentration V ₂ was measured, it was found that V ₁ was 0.1 atomic. % or more, and the reduction rate of the phosphorus concentration calculated from the V ₁ and V ₂ is 25% or less,
The film adhesive contains an acrylic resin (a) and a crosslinking agent (f),
The acrylic resin (a) has a functional group capable of bonding with the crosslinking agent (f),
The crosslinking agent (f) is an aliphatic compound, and one or two selected from the group consisting of a triple bond between carbon atoms, a double bond between carbon atoms, and a cyano group. Examples include those that do not have the above.

A preferred embodiment of the film-like adhesive is, for example, a film-like adhesive for bonding a circuit-forming surface of a chip and a light-transmitting cover, comprising:
One side of the film-like adhesive before heating at 260°C was analyzed by X-ray photoelectron spectroscopy to measure the phosphorus concentration V ₁ , and the phosphorus concentration V ₁ was measured. Of the film adhesive after heating for 1 minute, the side on which V ₁ was measured was analyzed by X-ray photoelectron spectroscopy, and when the phosphorus concentration V ₂ was measured, it was found that V ₁ was 0.1 atomic. % or more, and the reduction rate of the phosphorus concentration calculated from the V ₁ and V ₂ is 25% or less,
The film adhesive contains a filler (d),
The filler (d) has an average particle diameter of 10 to 100 nm.

◇Laminated Sheet and Composite Sheet A laminated sheet according to an embodiment of the present invention includes the film adhesive and a resin film provided on one surface of the film adhesive. .
Further, a composite sheet according to an embodiment of the present invention includes the film adhesive and a dicing sheet provided on one surface of the film adhesive, and the dicing sheet is a base material. and an adhesive layer provided on one surface of the base material, and the adhesive layer is disposed between the base material and the film adhesive.

The laminated sheet only needs to have a resin film provided on at least one surface of the film adhesive, and may have a resin film provided only on one surface, or may have a resin film provided on both surfaces (i.e., one surface of the film adhesive). A resin film may be provided on the surface and the other surface on the opposite side.

In the laminated sheet, when the resin films are provided on both sides of the film adhesive, these resin films may be the same or different from each other, and the combination of these resin films is not particularly limited.

The resin film may be composed of one layer (single layer) or may be composed of two or more layers, and when composed of multiple layers, these multiple layers may be the same or different from each other. The combination of these multiple layers is not particularly limited.

The resin film may be a sheet containing only resin as a constituent material, or may be a sheet containing resin and other components as constituent materials, with resin as the main constituent material.

Examples of the resin that is a constituent material of the resin film include polyethylene such as low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), and high-density polyethylene (HDPE); polypropylene, polybutene, polybutadiene, and polymethylpentene. , polyolefins other than polyethylene such as norbornene resin; ethylene such as ethylene-vinyl acetate copolymer, ethylene-(meth)acrylic acid copolymer, ethylene-(meth)acrylic acid ester copolymer, ethylene-norbornene copolymer, etc. system copolymers (copolymers obtained using ethylene as a monomer); vinyl chloride resins such as polyvinyl chloride and vinyl chloride copolymers (resins obtained using vinyl chloride as a monomer); polystyrene; Polycycloolefins; polyesters such as polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, polyethylene isophthalate, polyethylene-2,6-naphthalene dicarboxylate, fully aromatic polyesters in which all constituent units have an aromatic cyclic group; Copolymers of two or more of the above polyesters; poly(meth)acrylates; polyurethanes; polyurethane acrylates; polyimides; polyamides; polycarbonates; fluororesins; polyacetals; modified polyphenylene oxides; polyphenylene sulfides; polysulfones; polyether ketones, etc. It will be done.
Examples of the resin include polymer alloys such as mixtures of the polyester and other resins. The polymer alloy of the polyester and other resin preferably has a relatively small amount of resin other than the polyester.
In addition, examples of the resin include, for example, a crosslinked resin obtained by crosslinking one or more of the resins exemplified above; modified ionomers using one or more of the resins exemplified above; Also mentioned are resins.

The resin film may be a release film or a base material described below. The base material will be explained in detail separately.

Examples of the release film include a plurality of layers including a resin layer and a release treatment layer provided on one surface of the resin layer.

The release film can be manufactured by subjecting one surface of the resin layer to a release treatment.
The resin layer can be produced by molding or coating a resin composition containing a resin, and drying it if necessary.

The resin that is the constituent material of the resin layer is the same as the resin that is the constituent material of the resin film.
The resin layer can be peeled off using various known release agents such as alkyd-based, silicone-based, fluorine-based, unsaturated polyester-based, polyolefin-based, or wax-based.
The release agent is preferably an alkyd-based, silicone-based, or fluorine-based release agent in terms of heat resistance.

The resin layer may be composed of one layer (single layer) or may be composed of two or more layers, and when composed of multiple layers, these multiple layers may be the same or different from each other, The combination of these multiple layers is not particularly limited.

An example of a laminated sheet configured by providing the release film as a resin film on both sides of the film adhesive is the laminated sheet 109 shown in FIG. 1, for example.

An example of a laminated sheet in which a resin film is provided on only one side of the film-like adhesive is a laminated sheet 108 shown in FIG. 2, for example.
In the figures after FIG. 2, the same components as those shown in the already explained figures are given the same reference numerals as in the already explained figures, and detailed explanation thereof will be omitted.

The laminated sheet 108 shown here includes a resin film 19 on the first surface 13a of the film adhesive 13.
The resin film 19 is as described above, and may be a release film (for example, the first release film 151 or the second release film 152 in FIG. 1), or may be a base material described below.

The thickness of the resin film can be arbitrarily set depending on the purpose and is not particularly limited.
The thickness of the resin film may be, for example, 10 to 200 μm.

The laminated sheet of this embodiment is not limited to that shown in FIG. 2, but may be one in which a part of the structure is changed or deleted from that shown in FIG. 2, or one that has been previously described. It is also possible to add other configurations to the above. More specifically, it is as follows.

For example, the laminated sheet of this embodiment does not need to have anything on the second surface of the film adhesive, but the laminated sheet is provided in the area near the peripheral edge of the second surface of the film adhesive. A jig adhesive layer for fixing to a jig such as a ring frame may be provided.
The adhesive layer for the jig may have, for example, a single layer structure containing an adhesive component, or a multilayer structure in which layers containing an adhesive component are laminated on both sides of a sheet serving as a core material. It may be of.

For example, when the laminate sheet is viewed from above on the film adhesive side or the resin film side, the surface areas of the film adhesive and the resin film may be the same or almost the same. In the laminated sheet of this embodiment, the surface area of the film-like adhesive is smaller than the surface area of the resin film, and a partial region of the resin film may be exposed. In that case, for example, at least the peripheral edge of the resin film in the width direction may be exposed without being covered with the film adhesive. Such a laminated sheet may include the above-mentioned jig adhesive layer on the exposed surface of the resin film.

FIG. 3 is a cross-sectional view schematically showing an example of a composite sheet according to an embodiment of the present invention.
The composite sheet 101 shown here includes a film adhesive 13 and a dicing sheet 10 provided on the second surface 13b of the film adhesive 13, and the dicing sheet 10 includes a base material 11, An adhesive layer 12 provided on one surface (sometimes referred to as "first surface" in this specification) 11a of the base material 11, and the adhesive layer 12 is provided on one surface 11a of the base material 11. 11 and a film adhesive 13.
In other words, the composite sheet 101 is constructed by laminating the base material 11, the adhesive layer 12, and the film adhesive 13 in this order in the thickness direction.
The surface 10a of the dicing sheet 10 on the film adhesive 13 side (herein sometimes referred to as the "first surface") is the surface of the adhesive layer 12 on the opposite side to the base material 11 (the main surface). In the specification, this is the same as 12a (sometimes referred to as the "first surface").

The composite sheet 101 further includes a release film 15 on the film adhesive 13.
In the composite sheet 101, an adhesive layer 12 is laminated on the first surface 11a of the base material 11, and a film-like adhesive 13 is laminated on the entire surface or almost the entire surface of the first surface 12a of the adhesive layer 12. A release film 15 is laminated on the entire surface or substantially the entire surface of the first surface 13a of the adhesive 13.

The dicing sheet 10 may be a known one.
The base material 11 and adhesive layer 12 in the dicing sheet 10 will be explained in order.

The base material 11 in the dicing sheet 10 is in the form of a sheet or a film, and its constituent materials include, for example, various resins. Examples of the resin that is a constituent material of the dicing sheet 10 include the same resin that is a constituent material of the resin film in the laminated sheet.

The number of resins constituting the base material may be one type, or two or more types, and when there are two or more types, the combination and ratio thereof can be arbitrarily selected.

The base material may be composed of one layer (single layer) or may be composed of two or more layers, and when composed of multiple layers, these multiple layers may be the same or different from each other. The combination of these multiple layers is not particularly limited.

The thickness of the base material 11 is preferably 50 to 300 μm, more preferably 60 to 150 μm. When the thickness of the base material 11 is within such a range, the flexibility of the composite sheet 101 and the adhesion to the object to be applied are further improved.
Here, the "thickness of the base material" means the thickness of the entire base material. For example, the thickness of a base material consisting of multiple layers refers to the total thickness of all the layers that make up the base material. means.

The base material 11 is preferably one with high accuracy in thickness, that is, one in which variations in thickness are suppressed regardless of the location. Among the above-mentioned constituent materials, materials that can be used to construct the base material with such high precision in thickness include, for example, polyethylene, polyolefins other than polyethylene, polyethylene terephthalate, ethylene-vinyl acetate copolymer, etc. can be mentioned.

In addition to the main constituent materials such as the resin, the base material 11 contains various known additives such as fillers, colorants, antistatic agents, antioxidants, organic lubricants, catalysts, and softeners (plasticizers). You can leave it there.

The base material 11 may be transparent or opaque, may be colored depending on the purpose, or may have other layers deposited thereon.

The base material 11 is subjected to roughening treatment such as sandblasting, solvent treatment, corona discharge treatment, and electron beam treatment in order to improve the adhesion with other layers (in this case, the adhesive layer 12) provided thereon. The surface may be subjected to oxidation treatment such as irradiation treatment, plasma treatment, ozone/ultraviolet irradiation treatment, flame treatment, chromic acid treatment, hot air treatment, etc.
Further, the surface of the base material 11 may be subjected to primer treatment.
The base material 11 also has an antistatic coating layer; a layer that prevents the base material 11 from adhering to other sheets or from adhering to a suction table when the composite sheets are stacked and stored. etc. may be used.

The base material 11 can be manufactured by a known method. For example, the base material 11 containing resin can be manufactured by molding a resin composition containing the resin.

The adhesive layer 12 in the dicing sheet 10 is in the form of a sheet or a film, and contains an adhesive.
Examples of the adhesive include adhesive resins such as acrylic resin, urethane resin, rubber resin, silicone resin, epoxy resin, polyvinyl ether, polycarbonate, and ester resin, with acrylic resin being preferred. .

In addition, in this specification, the "adhesive resin" includes both resins having adhesive properties and resins having adhesive properties. For example, the above-mentioned adhesive resins include not only resins that are adhesive themselves, but also resins that exhibit adhesiveness when used in combination with other components such as additives, and resins that exhibit adhesiveness due to the presence of triggers such as heat or water. It also includes resins that show .

The adhesive layer 12 may be composed of one layer (single layer) or may be composed of two or more layers, and when it is composed of multiple layers, these multiple layers may be the same or different from each other. They may be different, and the combination of these multiple layers is not particularly limited.

The thickness of the adhesive layer 12 is not particularly limited, but is preferably 1 to 100 μm, more preferably 1 to 60 μm, and particularly preferably 1 to 30 μm.
Here, the "thickness of the adhesive layer" means the thickness of the entire adhesive layer. For example, the thickness of an adhesive layer consisting of multiple layers is the total thickness of all the layers that make up the adhesive layer. means the thickness of

The adhesive layer 12 may be formed using an energy ray curable adhesive or may be formed using a non-energy ray curable adhesive. That is, the adhesive layer 12 may be either energy ray curable or non-energy ray curable. The energy ray-curable adhesive layer 12 can easily adjust its physical properties before and after curing. For example, by curing the energy ray-curable adhesive layer 12, the adhesion to the object to which it is applied can be easily adjusted.

The adhesive layer 12 can be formed using an adhesive composition containing an adhesive. For example, the adhesive layer 12 can be formed at the desired site by applying an adhesive composition to the surface on which the adhesive layer 12 is to be formed and drying it if necessary. The content ratio of components that do not vaporize at room temperature in the adhesive composition is usually the same as the content ratio of the components in the adhesive layer 12. As used herein, "normal temperature" means a temperature that is not particularly cooled or heated, that is, a normal temperature, and includes, for example, a temperature of 15 to 25°C.

The adhesive composition may be applied by a known method, such as an air knife coater, blade coater, bar coater, gravure coater, roll coater, roll knife coater, curtain coater, die coater, knife coater, or screen coater. , a method using various coaters such as a Meyer bar coater and a kiss coater.

When providing the adhesive layer 12 on the base material 11, for example, the adhesive layer 12 is formed on the base material 11 by coating an adhesive composition on the base material 11 and drying it as necessary. All you have to do is laminate them. In addition, when providing the adhesive layer 12 on the base material 11, for example, by coating the adhesive composition on the release film and drying it as necessary, the adhesive layer 12 is formed on the release film. By bonding the exposed surface of the adhesive layer 12 to one surface (here, the first surface 11a) of the base material 11, even if the adhesive layer 12 is laminated on the base material 11. good. In this case, the release film may be removed during either the manufacturing process or the usage process of the composite sheet 101.

When the adhesive layer 12 is energy ray curable, the energy ray curable adhesive composition may be, for example, non-energy ray curable adhesive resin (I-1a) (hereinafter referred to as "adhesive resin (I-1a)"). A pressure-sensitive adhesive composition (I-1) containing an energy ray-curable compound (sometimes abbreviated as "-1a)"; Adhesive composition (I-2) containing introduced energy ray-curable adhesive resin (I-2a) (hereinafter sometimes abbreviated as "adhesive resin (I-2a)"); Examples include an adhesive composition (I-3) containing an adhesive resin (I-2a) and an energy ray-curable compound.

When the adhesive layer 12 is non-energy ray curable, examples of the non-energy ray curable adhesive composition include the adhesive composition (I-4) containing the adhesive resin (I-1a). etc.

The film adhesive 13 has the above-mentioned light transmittance. For example, at least one of the first surface 13a and the second surface 13b of the film adhesive 13 satisfies the above-mentioned conditions of V ₁ , V ₂ and P concentration reduction rate.
The thickness of the film adhesive 13 is preferably 10 to 40 μm.
The film adhesive 13 can be formed using the above adhesive composition.

The release film 15 is similar to the first release film 151 or the second release film 152 shown in FIG.

Not only in the case of the composite sheet 101, but also in the composite sheet of this embodiment, the release film (for example, the release film 15 shown in FIG. 3) may have any configuration, and the composite sheet of this embodiment may include a release film. You may or may not have one.

The composite sheet 101 is used with the release film 15 removed and an object (for example, the circuit-forming surface of a chip) attached to the first surface 13a of the film adhesive 13.

The composite sheet of this embodiment is not limited to that shown in FIG. 3, but may be one in which a part of the structure is changed or deleted from that shown in FIG. 3, or one that has been previously described. It is also possible to add other configurations to the above. More specifically, it is as follows.

Up to this point, a composite sheet including a dicing sheet configured by laminating a base material and an adhesive layer has been described, but the composite sheet of this embodiment may include a dicing sheet consisting only of a base material. . That is, the composite sheet includes a base material and a film adhesive provided on one surface of the base material, and an adhesive layer is provided between the base material and the film adhesive. It may be configured without being arranged. Such a composite sheet includes a laminated sheet 108 shown in FIG. 2 in which the resin film 19 is a base material (for example, the base material 11 shown in FIG. 3).

Up to this point, a composite sheet including a dicing sheet configured by laminating a base material and an adhesive layer has been described, but the composite sheet of this embodiment includes an intermediate layer in addition to the base material and adhesive layer. The dicing sheet may include a structured dicing sheet. Such a dicing sheet includes, for example, a base material, an adhesive layer provided on one surface of the base material, and a surface of the adhesive layer provided on the opposite side of the base material. An example of this is an intermediate layer with an intermediate layer. When such a dicing sheet is used, an intermediate layer is disposed between the pressure-sensitive adhesive layer and the film adhesive in the composite sheet.

For example, the composite sheet of the present embodiment may include only the release film on the first surface of the film-like adhesive; A jig adhesive layer for fixing the composite sheet to a jig such as a ring frame may be provided.
The jig adhesive layer in this case is the same as that described above.

For example, when the composite sheet is viewed from above on the film adhesive side or the dicing sheet side, the surface areas of the film adhesive and the dicing sheet may be the same or almost the same. In this composite sheet, the surface area of the film adhesive may be smaller than the surface area of the dicing sheet, and a partial region of the dicing sheet (for example, the adhesive layer) may be exposed. In that case, for example, at least the peripheral edge of the dicing sheet in the width direction may be exposed without being covered with the film adhesive. Such a composite sheet may include the above-mentioned jig adhesive layer on the exposed surface of the dicing sheet.

Up to this point, the base material, adhesive layer, intermediate layer, film adhesive, jig adhesive layer, and release film have been shown as constituents of the composite sheet, but the composite sheet of this embodiment includes: It may also include other layers that do not fall under any of these.
When the composite sheet includes the other layer, the location thereof is not particularly limited.

In the composite sheet of this embodiment, the size and shape of each layer can be arbitrarily selected depending on the purpose.

◇How to use the laminated sheet (film adhesive)<<Laminated body and its manufacturing method>>
The film adhesive in the laminated sheet of this embodiment can be used, for example, as a film for adhering a light-transmissive cover to the circuit-forming surface of a chip such as a sensor.
More specifically, by using the film adhesive, the chip, the film adhesive provided on the circuit forming surface of the chip, and the surface of the film adhesive opposite to the chip side. A laminate including a light-transmitting cover provided thereon can be manufactured. In the laminate, one or both of the chip-side surface of the film adhesive and the light-transmissive cover-side surface satisfy the above-mentioned conditions of V ₁ , V ₂ and P concentration reduction rate, It is preferable that both satisfy the above-mentioned conditions of V ₁ , V ₂ and P concentration reduction rate.

FIG. 4 is a cross-sectional view schematically showing an example of the laminate.
The laminate 801 shown here includes a chip 8, a film adhesive 13 provided on the circuit forming surface 8a of the chip 8, and a surface (first surface) of the film adhesive 13 on the opposite side to the chip 8 side. and a light-transmissive cover 7 provided on the cover 13a.

In the laminate 801, the opposing surfaces of the chip 8 and the film adhesive 13, that is, the circuit forming surface 8a of the chip 8, and the surface (second surface) 13b of the film adhesive 13 on the chip 8 side. , are in direct contact. Further, the opposing surfaces of the film adhesive 13 and the light-transmitting cover 7, that is, the first surface 13a of the film-like adhesive 13 and the surface of the light-transmitting cover 7 on the film-like adhesive 13 side (main 7b (sometimes referred to as the "second surface" in the specification) are in direct contact with each other.
In this way, in the laminate 801, the chip 8, the film-like adhesive 13, and the light-transmitting cover 7 are laminated in this order in the thickness direction, and the circuit-forming surface 8a of the chip 8 is layered in the film-like direction. It is arranged and configured on the adhesive 13 side.

The film adhesive 13 in the laminate 801 is, for example, the laminate sheet 109 shown in FIG. 1 with the first release film 151 and the second release film 152 removed, or the laminate sheet 108 shown in FIG. The resin film 19 is removed.
In the laminate 801, one or both of the first surface 13a and the second surface 13b of the film adhesive 13 satisfy the above-mentioned conditions of V ₁ , V 2 and P concentration reduction rate, and both satisfy the above-mentioned conditions of V 1 , V ₂ and P concentration reduction rate. It is preferable to satisfy the conditions of V ₁ , V ₂ and P concentration reduction rate.

Note that in FIG. 4, illustration of the circuit of the chip 8 is omitted. Further, the reference numeral 7a indicates a surface of the light-transmissive cover 7 opposite to the second surface 7b (in this specification, it may be referred to as a "first surface").

The light-transmitting cover 7 protects the circuit forming surface 8a of the chip 8, and makes the outside of the second surface 7b visible from the outside of the first surface 7a.
On the other hand, the film adhesive 13 has the above-mentioned light transmittance. Therefore, in the laminate 801, visual information present on the circuit forming surface 8a of the chip 8 is transmitted through the light-transmitting cover 7 and the film-like adhesive 13 (over the light-transmitting cover 7 and the film-like adhesive 13). is visible.
Furthermore, as described above, the film adhesive 13 has high light transmittance before and after heating, and coloration is suppressed. Therefore, the laminate 801 allows the visual information on the chip 8 to be viewed stably and with high precision.

For example, a fingerprint sensor can be used as the chip 8, and in that case, the laminate 801 can be used as a fingerprint sensor module.

The laminate using the film adhesive is not limited to the one shown in FIG. 4, and may be one in which a part of the structure is changed or deleted from the one shown in FIG. 4 without impairing the effects of the present invention. , other configurations may be added to those described above.

In the laminate, for example, a circuit forming surface of a chip is bonded to one surface (second surface) of the film adhesive, and a light-transmitting surface is attached to the other surface (first surface) of the film adhesive. It can be manufactured by pasting together a plastic cover.

◇How to use the composite sheet <<Laminated body and its manufacturing method>>
The composite sheet of this embodiment can be used in the same manner as known composite sheets.
FIG. 5 is a sectional view schematically illustrating an example of how to use the composite sheet of this embodiment. Here, a case is shown in which the composite sheet 101 shown in FIG. 3 is used.

As shown here, the composite sheet 101 is used by attaching the first surface 13a of the film adhesive 13 to the circuit forming surface 8a of the chip 8 after removing the release film 15.

After the composite sheet 101 is attached to the chip 8, for example, the chip 8 is diced into individual pieces, and the film adhesive 13 is cut along the outer periphery of the individual chip 8. At this time, cutting the chip 8 into pieces and cutting the film adhesive 13 can be performed by a known method. For example, these may be done at the same time, or separately after cutting the chip 8 into pieces. , the film adhesive 13 may be cut.

Next, the diced chips 8 are separated from the dicing sheet 10 together with the cut film adhesive 13 and picked up. When the adhesive layer 12 is energy ray-curable, the adhesive layer 12 is cured with energy rays to reduce its adhesive strength to the film adhesive 13 before being picked up, thereby making it easier to pick up. It can be carried out.

Next, the laminate (for example, the laminate 801 shown in FIG. 4) can be manufactured by laminating a light-transmitting cover to the second surface of the film-like adhesive 13 after cutting and picking up.
In the laminate, either one or both of the first surface and the second surface of the film adhesive satisfies the conditions of the above-mentioned V ₁ , V ₂ and P concentration reduction rate, and both of the above-mentioned V ₁ , It is preferable to satisfy the conditions of _V2 and P concentration reduction rate.

Here, in this way, the film adhesive in the composite sheet is attached to the chip, and after the chips are separated into individual pieces and the film adhesive is cut, a light-transmitting cover is attached to the cut film adhesive. Although the case of bonding has been described, the order of bonding the chip and the light-transmitting cover to the film adhesive may be reversed. That is, after pasting the first side of the film-like adhesive on the second side of the light-transmitting cover, the light-transmitting cover is diced into pieces, the film-like adhesive is cut, and the film-like adhesive is cut into pieces. After curing the adhesive layer with energy rays, the light-transmissive cover after being cut into pieces is separated from the dicing sheet and picked up together with the cut film-like adhesive, and then the film-like adhesive after cutting and picking up is separated from the dicing sheet and picked up. The laminate (for example, the laminate 801 shown in FIG. 4) can also be manufactured by bonding a chip to the first surface of the agent.

Hereinafter, the present invention will be explained in more detail with reference to specific examples. However, the present invention is not limited to the examples shown below.

<Raw materials for manufacturing adhesive composition>
In the present examples and comparative examples, the raw materials used for manufacturing the adhesive compositions are shown below.

[Acrylic resin (a)]
(a)-1: Acrylic resin (weight average molecular weight 800,000, glass transition temperature 6° C.) obtained by copolymerizing methyl acrylate (85 parts by mass) and 2-hydroxyethyl acrylate (15 parts by mass).
(a)-2: Acrylic resin (weight average molecular weight 800,000, glass transition temperature 9°C) obtained by copolymerizing methyl acrylate (95 parts by mass) and 2-hydroxyethyl acrylate (5 parts by mass).
[Epoxy compound (b1)]
(b1)-1: Cresol novolak type epoxy resin to which an acryloyl group has been added (“CNA147” manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent: 518 g/eq, number average molecular weight: 2100, content of unsaturated groups and content of epoxy groups) (equivalent amount)
(b1)-2: Hydrogenated bisphenol A type epoxy resin (“Epolite 4000” manufactured by Kyoeisha Chemical Co., Ltd., epoxy equivalent 310 to 340 g/eq)
[Phenol resin (b2)]
(b2)-1: Aralkyl type phenol resin (“HE100C-10” manufactured by Air Water Chemical Company)
[Curing accelerator (c)]
(c)-1: Triphenylphosphine (manufactured by Hokuko Chemical Industry Co., Ltd.)
[Filler (d)]
(d)-1: Spherical silica modified with methacrylic group (“YA050C-MJE” manufactured by Admatex, average particle diameter 50 nm)
(d)-2: Spherical silica modified with epoxy group (“YA050C-MKK” manufactured by Admatex, average particle size 50 nm)
(d)-3: Silica filler modified with epoxy group (“SC2050MA” manufactured by Admatex, average particle diameter 500 nm)
[Crosslinking agent (f)]
(f)-1: Tolylene diisocyanate trimer adduct of trimethylolpropane (“Coronate L” manufactured by Tosoh Corporation)
(f)-2: Isophorone diisocyanate trimer adduct of trimethylolpropane (“D-140N” manufactured by Mitsui Chemicals)
[Phosphorous antioxidant (z)]
(z)-1: Bis(decyl)pentaerythritol diphosphite (JPE-10 manufactured by Johoku Kagaku Kogyo Co., Ltd., aliphatic phosphite)

[Example 1]
<<Manufacture of film adhesive>>
<Manufacture of adhesive composition>
Acrylic resin (a)-1 (57.2 parts by mass), epoxy compound (b1)-1 (18 parts by mass), phenolic resin (b2)-1 (3 parts by mass), curing accelerator (c)-1 (0.5 parts by mass), filler (d)-1 (20 parts by mass), crosslinking agent (f)-1 (0.5 parts by mass), and phosphorus antioxidant (z)-1 (0.8 parts by mass). Part by mass) was dissolved or dispersed in methyl ethyl ketone and stirred at 23°C to obtain an adhesive composition in which the total concentration of all components other than methyl ethyl ketone was 32% by mass. It should be noted that all the blending amounts of components other than methyl ethyl ketone shown here are the blending amounts of the target product without solvent components.

<Manufacture of film adhesive>
A release film ("SP-PET381031" manufactured by Lintec Corporation, thickness 38 μm), in which one side of a polyethylene terephthalate (PET) film has been subjected to release treatment by silicone treatment, was used, and the adhesive obtained above was applied to the release treatment surface. A film adhesive having a thickness of 20 μm is formed by applying the agent composition and heating and drying it at 100° C. for 2 minutes, and the release film and film adhesive are laminated in the thickness direction. A structured adhesive sheet was obtained.

<<Evaluation of film adhesive>>
<Measurement of shear strength>
Using a tape mounter ("Adwill RAD2500 m/12" manufactured by Lintec Corporation), a dicing sheet ("Adwill D-678" manufactured by Lintec Corporation) was placed on a 6-inch silicon wafer ("Adwill D-678" manufactured by Lintec Corporation) under conditions of a sticking temperature of 23°C and a sticking speed of 20 mm/s. 350 μm thick), and the laminate of the dicing sheet and silicon wafer was fixed to a ring frame.
Next, dicing was performed using a dicing device (“DFD6362” manufactured by DISCO) and a dicing blade (“NBC-ZH2050-SE27HECC” manufactured by DISCO) at a blade rotation speed of 30,000 rpm and a cutting speed of 40 mm/s to determine the size. A plurality of silicon chips (hereinafter sometimes referred to as "silicon chip group") measuring 2 mm x 2 mm were obtained.The above-mentioned dicing sheet is composed of a base material and an adhesive layer laminated, and the dicing sheet Occasionally, cuts were made with a dicing blade to a depth of 20 μm in the base material in this dicing sheet.

Next, the adhesive sheet obtained above was attached to the group of silicon chips obtained above while heating it to 60° C. using the film adhesive therein. At this time, the adhesive sheet was attached to the surface (exposed surface) of the silicon chips in the silicon chip group opposite to the side to which the dicing sheet was attached. The attached adhesive sheet was then cut along the outer periphery of the silicon chip.
Through the above process, a laminate having a size of 2 mm x 2 mm was obtained, in which the dicing sheet, the silicon chip, and the adhesive sheet were laminated in this order in the thickness direction.

Next, the release film was removed from the film adhesive in this laminate, and using a manual die bonder, the newly formed exposed surface of the film adhesive was cut to a size of 30 mm x 30 mm and a thickness of 300 μm. It was attached to the surface of a certain copper plate. At this time, the film adhesive was attached by pressing it against the copper plate while applying a force of 2.45 N (250 gf) while heating it to 125°C. Furthermore, a test piece was obtained by heating these bonded materials at 175° C. for 5 hours.

Next, using a universal bond tester ("DAGE4000" manufactured by Nordson Advanced Technologies), a film-like adhesive was formed on the side surface of the test piece at a speed of 200 μm/s with a shear tool at a temperature of 23°C. A force was applied to both the adhesive and the silicon chip in a direction parallel to the surface of the film adhesive that was attached to the copper plate. Then, the maximum value of the force applied until the film adhesive was destroyed was confirmed, and this was adopted as the shear strength (N/2 mm□) of the film adhesive. The results are shown in Table 1.

<Measurement of linear transmittance of light (400 to 800 nm) before heating>
The film adhesive obtained above was attached to one side of a glass preparation (thickness: 0.9 mm) while heating at 40°C. The film adhesive was not heat-treated immediately after its manufacture until it was applied.
Next, cut off the part of the film-like adhesive that protrudes from the glass preparation after pasting, and with the film-like adhesive and glass preparation of the same size aligned with their peripheral edges, A test piece (hereinafter referred to as a "pre-heating test piece") constructed by laminating these in the thickness direction was obtained.

Regarding the glass preparation used to prepare the pre-heated test piece, before preparing the pre-heated test piece, a straight line of light (400 to 800 nm) was measured using a spectrophotometer ("UV-3101PC" manufactured by Shimadzu). Transmittance (hereinafter referred to as "standard in-line transmittance") was measured.
The linear transmittance of light (400 to 800 nm) was also measured for the pre-heated test piece obtained above using the same method.
The value obtained by subtracting the measured value of the standard in-line transmittance at the same wavelength from the measured value of the in-line transmittance of light (400 to 800 nm) at each wavelength of the test piece before heating is calculated as It was adopted as the linear transmittance of light (400 to 800 nm) of the adhesive (ie, the linear transmittance before heating). The results are shown in Table 1.

<Measurement of linear transmittance after heating of light (400 to 800 nm)>
Using an electric furnace, the test piece after measuring the linear transmittance of the light (400 to 800 nm) before heating was heated at 260° C. for 10 minutes.
Next, the heated test piece was allowed to cool to the same temperature as room temperature.
Next, for this test piece after heating and cooling (hereinafter referred to as "test piece after heating"), the linear transmittance of light (400 to 800 nm) was measured in the same manner as in the case of the test piece before heating described above. did.
The value obtained by subtracting the measured value of the standard in-line transmittance at the same wavelength from the measured value of the in-line transmittance of light (400 to 800 nm) at each wavelength of the test piece after heating is calculated as It was adopted as the linear transmittance of light (400 to 800 nm) of the adhesive (ie, the linear transmittance after heating). The results are shown in Table 1.

<Evaluation of fingerprint recognition before heating using RGB>
Place a digital camera ("IXY650" manufactured by Canon) in front of the pad of your left index finger, adjust the distance between the pad of your left index finger and the surface of the camera lens to 50 mm, and hold it in this state. Imaging data of the fingerprint of the index finger of the left hand (hereinafter referred to as "reference imaging data") was acquired in macro mode.
While maintaining the positional relationship between the left index finger and the digital camera, the pre-heated test piece was further placed between the pad of the left index finger and the digital camera. At this time, the straight line connecting the pad of the index finger of the left hand and the digital camera is aligned with the exposed surface of the glass preparation in the pre-heated test piece (i.e., the surface opposite to the surface to which the film adhesive is attached). The test piece before heating was arranged so that the test pieces were perpendicular to each other and the exposed surface faced the digital camera side. Under these conditions, imaging data of the fingerprint of the index finger of the left hand (hereinafter referred to as "transmission imaging data before heating") was acquired in macro mode using the same method as when acquiring the reference imaging data.

Using graphic software ("Paint" manufactured by Microsoft Corporation), the reference imaging data and pre-heating transmission imaging data obtained above are expanded, and the colors of the peaks and valleys of the fingerprint are extracted from each data. Quantified in RGB.
The value obtained by subtracting the R value of the fingerprint peak obtained from the standard imaging data from the R value of the fingerprint peak obtained from the transmission imaging data before heating is calculated as the R value of the fingerprint peak at the time of pre-heating evaluation. adopted as the value. In a similar manner to this, the G value and B value of the ridges of the fingerprint at the time of pre-heating evaluation were determined.
In the same manner as above, the value obtained by subtracting the R value of the fingerprint valley obtained from the standard imaging data from the R value of the fingerprint valley obtained from the pre-heating transmission imaging data is calculated at the time of pre-heating evaluation. was adopted as the R value of the valley of the fingerprint. In the same manner as this, the G value and B value of the troughs of the fingerprint at the time of pre-heating evaluation were determined.
Furthermore, the absolute value of the difference between the R value of the peak part and the R value of the valley part (hereinafter sometimes referred to as "absolute value ΔR") is calculated, and the G value of the peak part and the R value of the valley part are calculated. The absolute value of the difference between the G value (hereinafter sometimes referred to as "absolute value ΔG") of (sometimes referred to as "absolute value ΔB") was calculated.

Based on these calculated values, the fingerprint recognizability of the RGB film adhesive before heating was evaluated according to the following criteria. The results are shown in Table 1.
(Evaluation criteria)
A: At least one of the absolute value ΔR, absolute value ΔG, and absolute value ΔB is 10 or more.
B: Absolute value ΔR, absolute value ΔG, and absolute value ΔB are all less than 10, and at least one of absolute value ΔR, absolute value ΔG, and absolute value ΔB is 5 or more.
C: Absolute value ΔR, absolute value ΔG, and absolute value ΔB are all less than 5.

<Evaluation of fingerprint recognition after heating using RGB>
The fingerprint of the film adhesive after heating using RGB was evaluated using the same method as in the above-mentioned "evaluation of fingerprint recognition before heating" except that the post-heating test piece was used instead of the pre-heating test piece. Recognizability was evaluated.
More specifically, during this evaluation, "post-heating transmission imaging data" was acquired in place of the pre-heating transmission imaging data. In addition, using this post-heating transmission imaging data, in place of the R value, G value, and B value of the fingerprint peak part during the pre-heating evaluation, the R value, G value, and B value of the fingerprint peak part during the post-heating evaluation. The B value was determined, and instead of the R value, G value, and B value of the fingerprint valley at the time of pre-heating evaluation, the R value, G value, and B value of the fingerprint valley at the time of post-heating evaluation were determined. Furthermore, from these R value, G value, and B value, in place of the above-mentioned absolute value ΔR, absolute value ΔG, and absolute value ΔB at the time of pre-heating evaluation, the absolute value ΔR, absolute value ΔG, and absolute value ΔB at the time of post-heating evaluation. was calculated. The results are shown in Table 1.

<Visual evaluation of fingerprint recognition before heating>
Five observers were selected at random, and each person visually observed the fingerprints using the method described below.
That is, one observer is placed in front of the pad of the left index finger, the distance between the pad of the left index finger and the observer's eye is adjusted to 150 mm, and in this state the distance between the pad of the left index finger is adjusted to 150 mm. Fingerprints were directly visually observed.
While maintaining the positional relationship between the left index finger and the observer, the pre-heated test piece was further placed between the pad of the left index finger and the observer. The arrangement of the pre-heated test piece at this time was the same as that of the pre-heated test piece in the above-mentioned "RGB evaluation of fingerprint recognition before heating". Under these conditions, the fingerprint of the index finger of the left hand was visually observed through the pre-heated test piece in the same manner as in the case of direct visual observation as described above.

Using this method, all five observers visually observed the fingerprints directly and through the unheated test piece, and compared the way the fingerprints looked through the unheated test piece and the way they looked directly. From the comparison of , the fingerprint recognizability of the film adhesive before heating was visually evaluated according to the following criteria. The results are shown in Table 1. The number in parentheses in the "Fingerprint Recognizability" column of Table 1 indicates "the number of observers who determined that there was no difference in the visibility of the fingerprints."
A: All five observers judged that there was no difference in the appearance of the fingerprints.
B: Four out of five observers judged that there was no difference in the appearance of the fingerprints.
C: Two or more out of five observers judged that the colors of the fingerprints were different from each other and that there was a difference in appearance.

<Visual evaluation of fingerprint recognition after heating>
The film adhesive was visually inspected after heating using the same method as in the above-mentioned "Visual evaluation of fingerprint recognition before heating" except that the post-heating test piece was used instead of the pre-heating test piece. The fingerprint recognition was evaluated. The results are shown in Table 1.

<Measurement of _V1 >
Using an X-ray photoelectron spectrometer (“Quantera SXM” manufactured by ALBAC PHI), one side of the film adhesive obtained above (hereinafter referred to as “film adhesive before heating”) was XPS analysis was performed by survey scanning an area of 1 mm x 1 mm at a measurement angle of 45° and a beam diameter of 18 μm, and the P concentration V ₁ on this surface was measured. At this time, a peak detected in the binding energy range of 123 to 143 eV was determined to be a P2p spectrum. Aluminum was used as the X-ray source. The film adhesive was not heat-treated immediately after its manufacture until this measurement. The results are shown in Table 1.

<Measurement of _V2 >
Using an electric furnace, the unheated film adhesive after measuring _V1 was heated at 260° C. for 10 minutes.
Next, the heated film adhesive was allowed to cool to the same temperature as room temperature.
Next, of the film adhesive after heating and cooling (hereinafter referred to as "film adhesive after heating"), the measurement surface of _V1 was the same as in the case of the film adhesive before heating described above. According to the method, XPS analysis was performed to measure the P concentration _V2 . The results are shown in Table 1.

<Calculation of P concentration reduction rate>
The P concentration reduction rate was calculated from V ₁ and V ₂ obtained above. The results are shown in Table 1.

<<Manufacture and evaluation of film adhesive>>
[Examples 2 to 5]
The point that either or both of the types and amounts of the ingredients in the adhesive composition were changed at the time of manufacturing the adhesive composition so that the types and amounts of the ingredients in the adhesive composition were as shown in Table 1. Except for this, a film adhesive was produced and evaluated in the same manner as in Example 1. The results are shown in Table 1.

[Comparative Examples 1-2]
Changed either or both of the types and amounts of the ingredients when manufacturing the adhesive composition so that the types and amounts of the ingredients contained in the adhesive composition are as shown in Table 2. Except for this, production and evaluation of a film adhesive was attempted in the same manner as in Example 1. The results are shown in Table 2.

In addition, the description "-" in the column of contained components in Tables 1 and 2 means that the adhesive composition does not contain that component.
In addition, "-" in the evaluation results column in Tables 1 and 2 indicates that the item could not be evaluated (if the data could not be obtained, or if the data was below the detection limit). ), or the data could not be calculated.

As is clear from the above results, in Examples 1 to 5, the film adhesives before and after heating at 260° C. all had high light transmittance, suppressed coloring, and had high fingerprint recognizability. In Examples 1 to 5, the linear transmittance of light (400 to 800 nm) of the film adhesive before heating at 260°C was 95% or more (95 to 97%), and the film adhesive after heating at 260°C The linear transmittance of the adhesive for light (400 to 800 nm) was 85% or more (85 to 94%).

In Examples 1 to 5, the shear strength of the film adhesive was 48 N/2 mm square or more (48 to 95 N/2 mm square), and the adhesive strength of the film adhesive was sufficiently strong.

In Examples 1 to 5, V ₁ is 0.15 atomic % or more (0.15 to 0.40 atomic %), and V ₂ is 0.14 atomic % or more (0.14 to 0.39 atomic %). ), and the P concentration reduction rate was small at 14.3% or less (2.5 to 14.3%).
Thus, in Examples 1 to 5, the concentration of phosphorus in the film adhesive before and after heating was high, and the film adhesive after heating also had a sufficient amount to exhibit sufficient antioxidant effect. It was confirmed that it contained a phosphorus antioxidant (z).

On the other hand, in Comparative Example 1, although the film adhesive before heating at 260°C had high light transmittance and coloring was suppressed, the film adhesive after heating at 260°C The coloring was not suppressed, and the fingerprint recognition was low.
In Comparative Example 1, since the film adhesive did not contain an antioxidant, it was assumed that coloring due to heating was not suppressed.
In Comparative Example 1, V ₁ and V ₂ were naturally below the detection limit values, and the P concentration reduction rate could not be calculated.

In Comparative Example 2, the film adhesive before heating at 260° C. already had low light transmittance, was cloudy white, and had low fingerprint recognition. Therefore, the film adhesive after heating at 260° C. also remained cloudy and had low fingerprint recognizability.
In Comparative Example 2, it was assumed that the film adhesive became cloudy because filler (d)-3 having a large average particle diameter was used. This is clear from the comparison between the film adhesive of Example 4 and the film adhesive of Comparative Example 2, which have very similar compositions except for the difference in the type of filler (d) used. Met.
In Comparative Example 2, it was not possible to confirm whether coloring due to heating was suppressed due to the influence of this turbidity, but since the film adhesive did not contain an antioxidant, naturally coloring due to heating was not suppressed. It was speculated that.
In Comparative Example 2, V ₁ and V ₂ were naturally below the detection limit values, and the P concentration reduction rate could not be calculated.

Furthermore, in Comparative Example 1, the shear strength of the film adhesive was 44 N/2 mm□, and the adhesive strength of the film adhesive was weaker than in Examples 1 to 5.

The present invention can be used as an adhesive when manufacturing or processing various parts constituting electronic equipment.

101... Composite sheet, 108, 109... Laminated sheet, 10... Dicing sheet, 11... Base material, 11a... First surface of base material, 12... Adhesive layer, 13 ... Film adhesive, 13a... First surface of film adhesive, 13b... Second surface of film adhesive, 151... First release film, 152... Second release Film, 19... Resin film, 7... Light-transmissive cover, 8... Chip, 8a... Circuit forming surface of chip, 801... Laminate

Claims (8)

A film adhesive for bonding a circuit forming surface of a chip and a light-transmitting cover,
Contains an acrylic resin (a), an epoxy compound (b1), a phosphorus antioxidant (z), and an aliphatic polyvalent isocyanate crosslinking agent,
The acrylic resin (a) has a functional group capable of bonding with the aliphatic polyvalent isocyanate crosslinking agent,
In the film adhesive, the content ratio of the acrylic resin (a) to the total mass of the film adhesive is 30 to 65% by mass,
The content of the epoxy compound (b1) is 5 to 100 parts by mass with respect to 100 parts by mass of the acrylic resin (a),
In the film adhesive, the content ratio of the phosphorus antioxidant (z) to the total mass of the film adhesive is 0.3 to 1.5% by mass,
One side of the film adhesive before heating at 260 ° C. is analyzed by X-ray photoelectron spectroscopy to measure the phosphorus concentration _V1 ,
After measuring the V ₁ and heating at 260° C. for 10 minutes, the surface of the film adhesive on which the V ₁ was measured was analyzed by X-ray photoelectron spectroscopy to determine the phosphorus concentration V ₂ When measuring
The V ₁ is 0.1 atomic % or more,
A film adhesive, wherein the rate of decrease in phosphorus concentration calculated from the above V ₁ and V ₂ is 25% or less. The film adhesive before heating at 260° C. has a linear transmittance of 90% or more for light having a wavelength of 400 to 800 nm,
The linear transmittance of the film adhesive after heating at 260° C. for 10 minutes for light having a wavelength of 400 to 800 nm is 85% or more,
The film adhesive according to claim 1, wherein the film adhesive has a thickness of 10 to 40 μm. The film adhesive according to claim 1 or 2, wherein the film adhesive contains an aliphatic epoxy compound as the epoxy compound (b1) . The film adhesive contains a phenolic resin (b2),
According to any one of claims 1 to 3, in the film adhesive, the content ratio of the phenolic resin (b2) to the total mass of the film adhesive is 10% by mass or less. Film adhesive. The film adhesive according to any one of claims 1 to 4, wherein the film adhesive contains an aliphatic phosphite as the phosphorus antioxidant (z) . A laminated sheet comprising the film adhesive according to any one of claims 1 to 5 and a resin film provided on one surface of the film adhesive. The film adhesive according to any one of claims 1 to 5 , and a dicing sheet provided on one surface of the film adhesive,
The dicing sheet includes a base material and an adhesive layer provided on one surface of the base material,
A composite sheet, wherein the adhesive layer is disposed between the base material and the film adhesive. A circuit forming surface of a chip is bonded to one surface of the film-like adhesive according to any one of claims 1 to 5 , and a light-transmitting cover is bonded to the other surface of the film-like adhesive. A method for producing a laminate, wherein the chip, the film adhesive, and the light-transmitting cover are laminated in this order to obtain a laminate.

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