KR20230123491A - Double-sided adhesive sheet for transfer - Google Patents

Abstract

An object of the present invention is to provide a double-sided pressure-sensitive adhesive sheet for transfer, in which displacement of electronic components is unlikely to occur even when irradiated with ultraviolet rays, and transfer accuracy can be maintained. The double-sided pressure-sensitive adhesive sheet for transfer of the present invention is a double-sided pressure-sensitive adhesive sheet for transfer in which a first pressure-sensitive adhesive layer, a base material, and a second pressure-sensitive adhesive layer are laminated in this order, wherein the first pressure-sensitive adhesive layer is composed of a low-adhesive pressure-sensitive adhesive layer , The second pressure-sensitive adhesive layer is composed of a peelable pressure-sensitive adhesive layer, and the first pressure-sensitive adhesive layer is lifted after irradiating an ultraviolet laser having a wavelength of 248 nm with a beam size of 130 × 105 μm, an output of 100 mJ / cm 2, a pulse width of 10 ns, and a frequency of 100 Hz. The ratio (R _{z1 /R z2 ) of the lifting height R z1 before irradiation to} the height R z2 is 0.2 to 1600.

Description

Double-sided adhesive sheet for transfer

The present invention relates to a double-sided pressure-sensitive adhesive sheet for transfer.

Conventionally, in the manufacturing process of a semiconductor device or the like, a semiconductor chip obtained by cutting a semiconductor wafer into pieces is received on a double-sided pressure-sensitive adhesive sheet for transfer on a carrier substrate and then transferred onto a mounting substrate (for example, patent literature One).

Japanese Unexamined Patent Publication No. 2005-263876

In the manufacturing process of a semiconductor device or the like, marking is sometimes performed on the double-sided pressure-sensitive adhesive transfer sheet to impart identification when transporting the pressure-sensitive adhesive transfer sheet from which semiconductor chips are received. However, when an ultraviolet laser is used for such marking, as shown in FIG. 5, the first pressure sensitive adhesive layer 12 peels off from the base material 10 and floats, thereby damaging the flatness of the double-sided pressure sensitive adhesive sheet for transfer and electronic parts. There was a problem that positional displacement of (21) would occur or transfer failure would easily occur.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a double-sided pressure-sensitive adhesive sheet for transfer that is resistant to misalignment of electronic parts even when irradiated with ultraviolet rays and can maintain transfer accuracy.

As a result of intensive examination to achieve the above object, the inventors of the present invention have a first pressure-sensitive adhesive layer for receiving minute electronic components such as semiconductor chips, and a second pressure-sensitive adhesive layer for temporarily fixing to a base material and a carrier substrate. Discovery of misalignment of electronic components and poor transfer even when marking with ultraviolet laser irradiation can be suppressed when a double-sided adhesive sheet for transfer having a ratio of lift height before irradiation to lift height after irradiation with ultraviolet laser is within a specified range did This invention was completed based on these knowledge.

That is, the present invention is a transfer double-sided pressure-sensitive adhesive sheet in which a first pressure-sensitive adhesive layer, a base material, and a second pressure-sensitive adhesive layer are laminated in this order,

The first pressure-sensitive adhesive layer is made of a low-adhesive pressure-sensitive adhesive layer,

The second pressure-sensitive adhesive layer is composed of a peelable pressure-sensitive adhesive layer,

The ratio of the lifting height R z1 before irradiation to the lifting height R _z2 after irradiating the first pressure-sensitive adhesive layer with an ultraviolet laser having a wavelength of 248 nm at a beam size of 130 × 105 μm, an output of 100 mJ / cm 2 , a frequency of 100 Hz, and a pulse width of 10 _ns ( A double-sided pressure-sensitive adhesive sheet for transfer, wherein R _z1 /R _z2 ) is 0.2 to 1600.

When the first pressure-sensitive adhesive layer was irradiated with an ultraviolet laser having a wavelength of 248 nm at a beam size of 130 × 105 μm, an output of 100 mJ/cm 2 , a frequency of 100 Hz, and a pulse width of 10 ns, the area ratio of the lifted area to the irradiated area was 20.0% or less. desirable.

The present invention is also a transfer double-sided pressure-sensitive adhesive sheet in which a first pressure-sensitive adhesive layer, a base material, and a second pressure-sensitive adhesive layer are laminated in this order,

The first pressure-sensitive adhesive layer is made of a low-adhesive pressure-sensitive adhesive layer,

The second pressure-sensitive adhesive layer is composed of a peelable pressure-sensitive adhesive layer,

When the first pressure-sensitive adhesive layer is irradiated with an ultraviolet laser having a wavelength of 248 nm at a beam size of 130 × 105 μm, an output of 100 mJ / cm 2 , a pulse width of 10 ns, and a frequency of 100 Hz, the area ratio of the lifted area to the entire irradiated area is 20.0% or less. , To provide a double-sided pressure-sensitive adhesive sheet for transfer.

It is preferable that the ratio (R _z2 /t ₁ ) of the lifting height R _z2 (μm) to the thickness t ₁ (μm) of the first pressure-sensitive adhesive layer is 1.0 or less.

Since the flatness of the double-sided pressure-sensitive adhesive sheet for transfer of the present invention is hardly damaged even when irradiated with an ultraviolet laser, misalignment of electronic components and transfer failure can be suppressed, and transfer accuracy can be maintained.

1 is a cross-sectional schematic diagram showing an embodiment of the double-sided pressure-sensitive adhesive sheet for transfer according to the present invention.
Fig. 2 is a cross-sectional schematic diagram showing another embodiment of the double-sided pressure-sensitive adhesive sheet for transfer according to the present invention.
FIG. 3 is a cross-sectional schematic diagram showing an embodiment of a first step in a method for mounting electronic components on a mounting substrate using the double-sided pressure-sensitive adhesive sheet for transfer shown in FIG. 1 .
FIG. 4 is a cross-sectional schematic diagram showing an embodiment of a second step in a method for mounting electronic components on a mounting board using the double-sided pressure-sensitive adhesive sheet for transfer shown in FIG. 1 .
Fig. 5 is a cross-sectional schematic view showing a double-sided pressure-sensitive adhesive sheet for transfer, in which flatness is damaged by irradiation with an ultraviolet laser and misalignment occurs in the received electronic parts.

[Double-sided adhesive sheet for transfer]

A double-sided pressure-sensitive adhesive sheet for transfer according to an embodiment of the present invention has a laminated structure in which a first pressure-sensitive adhesive layer, a base material, and a second pressure-sensitive adhesive layer are laminated in this order, and the first pressure-sensitive adhesive layer is provided with an ultraviolet laser having a wavelength of 248 nm. The ratio (R z1 /R z2 ) of the lifting height R _z1 before irradiation to the lifting height R z2 after irradiating with a beam size of 130 × 105 μm, an output of 100 mJ / cm 2, a frequency of 100 Hz, and a pulse width of 10 _{ns (R z1 /} R _z2 ) is 0.2 to 1600. . An embodiment of the double-sided pressure-sensitive adhesive sheet for transfer of the present invention may be described below with reference to the drawings, but the double-sided pressure-sensitive adhesive sheet for transfer of the present invention is not limited to the embodiment. 1 is a cross-sectional schematic diagram showing an embodiment of a double-sided pressure-sensitive adhesive transfer sheet according to the present invention, in which 1 is a double-sided pressure-sensitive adhesive sheet for transfer, 10 is a base material, 11 is a first pressure sensitive adhesive layer, and 12 is a second pressure sensitive adhesive layer. .

The configuration in which the ratio (R _z1 /R _z2 ) is 0.2 to 1600 is preferable from the viewpoint of the positional accuracy of the electronic component received in the first pressure-sensitive adhesive layer, 0.4 to 1500 is more preferable, and 0.5 to 1400 is furthermore. desirable. In addition, the lifting heights R _z1 and R _z2 are the maximum heights of the amount of expansion in the vertical direction (Z-axis direction) of the irradiation unit after laser irradiation, for example, a laser microscope (product name "VK-X100", manufactured by Keyence Corporation). It can be obtained by analyzing the surface observation image obtained using

In the double-sided pressure-sensitive adhesive sheet for transfer of the present invention, when the first pressure-sensitive adhesive layer was irradiated with an ultraviolet laser having a wavelength of 248 nm at a beam size of 130 × 105 μm, an output of 100 mJ / cm 2, a frequency of 100 Hz, and a pulse width of 10 ns, It is preferable that the area ratio of the floating area is 20.0% or less. The structure that the said area ratio is 20.0% or less is preferable from a viewpoint of the positional accuracy of the electronic component received in the said 1st adhesive layer, 15.0% or less is more preferable, and 10.0% or less is still more preferable. The lower limit of the area ratio is usually 0%. In addition, the lifting area is the area of the part where the said low-adhesion adhesive layer peeled off from the said base material and floated, and can obtain|require it by analyzing the surface observation image imaged using the microscope, for example.

In the double-sided pressure-sensitive adhesive sheet for transfer according to the present invention, the ratio (R _z2 /t ₁ ) of the lifting height R _z2 (μm) to the thickness t ₁ (μm) of the first pressure-sensitive adhesive layer is preferably 1.0 or less. The configuration that the ratio (R _z2 /t ₁ ) is 1.0 or less is preferable from the viewpoint of the positional accuracy of the electronic component received in the first pressure-sensitive adhesive layer, more preferably 0.5 or less, and even more preferably 0.4 or less.

The above-described lifting height _Rz2 after ultraviolet laser irradiation and the area ratio of the lifting area are the adhesive strength by adjusting the type, composition, degree of crosslinking, etc. of the pressure-sensitive adhesive constituting the first pressure-sensitive adhesive layer, and the type and amount of the ultraviolet absorber. It can be adjusted by controlling reaction suppression of the base material by adjusting or adjusting the adhesion between the pressure-sensitive adhesive and the base material.

A double-sided pressure-sensitive adhesive sheet for transfer according to another embodiment of the present invention has a laminated structure in which a first pressure-sensitive adhesive layer, a base material, and a second pressure-sensitive adhesive layer are laminated in this order, and the first pressure-sensitive adhesive layer is coated with an ultraviolet laser having a wavelength of 248 nm. is irradiated with a beam size of 130 × 105 μm, an output of 100 mJ/cm 2 , a frequency of 100 Hz, and a pulse width of 10 ns, the area ratio of the lifted area to the irradiated area is 20.0% or less. The positional accuracy of the electronic component can be maintained by the configuration in which the area ratio is 20.0% or less. 15.0 % or less is preferable and, as for the said area ratio, 10.0 % or less is more preferable.

<First pressure sensitive adhesive layer>

In the double-sided pressure-sensitive adhesive sheet for transfer according to the present invention, the first pressure-sensitive adhesive layer is a pressure-sensitive adhesive layer for receiving and holding electronic parts, and is composed of a low-adhesion pressure-sensitive adhesive layer. The structure that the 1st adhesive layer consists of a low-adhesion adhesive layer is suitable at the point which can reduce the force applied to an electronic component at the time of receiving, and can suppress damage to an electronic component. In addition, when the 1st adhesive layer receives an electronic component non-contact, for example, it presses an electronic component with a pin member from a dicing tape, makes it peel, and makes it fall on a 1st adhesive layer. However, when the 1st adhesive layer receives the electronic component which fell, it jumps up and cannot receive it with high precision in some cases. When the said phenomenon occurs, the positional accuracy of an electronic product may fall and a contact defect may arise. The configuration that the first pressure-sensitive adhesive layer is made of a low-adhesive pressure-sensitive adhesive layer is such that when the first pressure-sensitive adhesive layer receives electronic parts in a non-contact manner, the electronic parts do not bounce off and are easily caught on the first pressure-sensitive adhesive layer, and are received with high positioning precision. It is also suitable in terms of being able to do it. Furthermore, it is preferable also from the point where the electronic component can be peeled easily from the 1st adhesive layer when mounting the electronic component received by the double-sided adhesive sheet for transfer to a mounting board.

The first pressure-sensitive adhesive layer can be made into a low-adhesive pressure-sensitive adhesive layer by adjusting the type, composition, degree of crosslinking, etc. of the pressure-sensitive adhesive constituting the pressure-sensitive adhesive, or by forming a weak boundary layer (WBL) by blending a light release agent or plasticizer. there is.

The 180° peel adhesion at 25°C to the PET film of the first pressure-sensitive adhesive layer is not particularly limited, but it can be received with high position accuracy without damaging electronic parts, and from the viewpoint of good transferability to the mounting substrate. , It is preferably 100 mN/25 mm or less, more preferably 50 mN/25 mm or less, still more preferably 10 mN/25 mm. Further, from the viewpoint of the adhesiveness of the electronic component to the first pressure sensitive adhesive layer, the 180° peel adhesive strength of the first pressure sensitive adhesive layer to the glass plate at 25°C is preferably 0.1 mN/25 mm or more, more preferably 1 mN/25 mm. More than that.

180 ° peel adhesive force at 25 ° C. to the PET film of the first pressure-sensitive adhesive layer (hereinafter, sometimes referred to as “P1a” in the present specification). The ratio (P1b/P1a) of the 180° peel adhesive strength at 25° C. (hereinafter sometimes referred to as “P1b” in the present specification) of the first pressure-sensitive adhesive layer to the PET film is not particularly limited, 3.0 or less is preferable and 2.5 or less is more preferable. In the configuration in which P1b/P1a is 3.0 or less, the adhesive strength of the first pressure-sensitive adhesive layer to the electronic component increases when the electronic component received by the double-sided pressure-sensitive adhesive sheet for transfer of the present invention is transferred and mounted on a mounting substrate by thermal compression bonding. It is preferable in that it can be detached satisfactorily and transferred to the mounting substrate without removing it.

The 180 ° peel adhesive strength at 25 ° C. is obtained by bonding the second pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive sheet for transfer to a glass plate, and bonding the PET film to the adhesive surface of the first pressure-sensitive adhesive layer, under the condition of a 2 kg roller and one reciprocating compression. It is pressure-bonded and aged for 30 minutes in an atmosphere of 23°C and 50% RH. After aging, in accordance with JIS Z 0237, the double-sided pressure-sensitive adhesive sheet for transfer is peeled from the adherend under conditions of a tensile speed of 300 mm/min and a peel angle of 180 ° in an atmosphere of 25 ° C. and 50% RH, resulting in 180 ° peel adhesive strength (mN/25 mm) is measured. The PET film is not particularly limited as long as it is untreated PET. For example, a trade name "Lumiror #25-S10, thickness: 23 µm" (manufactured by Toray Industries, Ltd.) is exemplified.

The surface force of the first pressure-sensitive adhesive layer can be adjusted by the type or composition of the pressure-sensitive adhesive, crosslinking degree, and additives such as fatty acid esters and fluorine-based surfactants.

In the double-sided pressure-sensitive adhesive sheet for transfer of the present invention, the storage modulus (E'1a) of the first pressure-sensitive adhesive layer by AFM-DMA at a frequency of 1 Hz and 25°C is preferably 50 MPa or less. This configuration is preferable when the first pressure-sensitive adhesive layer reliably adheres the received electronic component. When the above E'1a is too high, the adhesiveness of the electronic component to the first pressure-sensitive adhesive layer may decrease, causing problems such as misalignment or falling of the electronic component. From the viewpoint of the adhesiveness of the electronic component to the first pressure-sensitive adhesive layer, E'1a is preferably 40 MPa or less, and more preferably 30 MPa or less. Moreover, 20 MPa or less and 10 MPa or less may be sufficient. On the other hand, from the viewpoint of transferability from the first pressure-sensitive adhesive layer to the circuit board, E'1a is preferably 0.1 MPa or more. When the E′1a is too low, the adhesiveness of the electronic component to the first pressure-sensitive adhesive layer is too high, and the transferability when mounted on a mounting substrate may be impaired. From the viewpoint of the transferability of the electronic component to the mounting substrate, E'1a is preferably 0.2 MPa or more, and more preferably 0.5 MPa or more.

In the double-sided pressure-sensitive adhesive sheet for transfer according to the present invention, the storage modulus (E'1b) of the first pressure-sensitive adhesive layer by AFM-DMA at a frequency of 1 kHz and 25°C is preferably 100 MPa or less. This configuration is preferable in that when the first pressure-sensitive adhesive layer receives the electronic component in a non-contact manner, the electronic component is not bounced off the surface of the first pressure-sensitive adhesive layer and the electronic component can be received with high positioning accuracy. If the E'1b is too high, when dropping and receiving the electronic component without contacting the surface of the first pressure-sensitive adhesive layer, the electronic component is flipped and displaced from a predetermined position or turned over, so that the positional accuracy is likely to decrease. lose From the viewpoint of the positional accuracy of the electronic component relative to the first pressure-sensitive adhesive layer, E'1b is preferably 90 MPa or less, and more preferably 80 MPa or less. Further, it may be 70 MPa or less, 60 MPa or less, 50 MPa or less, 40 MPa or less, 30 MPa or less, and particularly 20 MPa or less. On the other hand, from the viewpoint of transferability from the first pressure-sensitive adhesive layer to the mounting substrate, E'1b is preferably 0.5 MPa or more. When the E'1b is too low, the adhesiveness of the electronic component to the first pressure-sensitive adhesive layer increases, and when the electronic component falls, it is embedded in the first pressure-sensitive adhesive layer, and transfer when mounting on a mounting substrate Sex may be damaged. From the viewpoint of the transferability of the electronic component to the mounting substrate, E'1b is preferably 0.7 MPa or more, and more preferably 1.0 MPa or more.

In the double-sided pressure-sensitive adhesive sheet for transfer of the present invention, the frequency by AFM-DMA of the first pressure-sensitive adhesive layer is 1 Hz, the frequency by AFM-DMA of the first pressure-sensitive adhesive layer for the storage modulus (E'1a) at 25 ° C. It is preferable that the ratio (E'1b/E'1a) of the storage elastic modulus (E'1b) at 1 kHz and 25°C is greater than 1.00. This configuration is preferable in terms of good balance of adhesiveness of the electronic component to the first pressure-sensitive adhesive layer, positional accuracy, transferability to the mounting substrate, and the like. From the viewpoint of a balance of adhesiveness of electronic parts, positional accuracy, transferability to a mounting substrate, etc., E'1b/E'1a is preferably 1.05 or more, and more preferably 1.10 or more. The upper limit of E'1b/E'1a is not particularly limited, but is preferably 3.00 or less from the viewpoint of the above balance.

In the double-sided pressure-sensitive adhesive sheet for transfer of the present invention, the loss modulus (E" 1a) of the first pressure-sensitive adhesive layer by AFM-DMA at a frequency of 1 Hz and 25 ° C. is preferably 7 MPa or less. It is preferable from the viewpoint of excellent transferability to the mounting substrate. When the above E"1a is too high, the adhesiveness of the electronic component to the first pressure-sensitive adhesive layer becomes too high, and the transferability at the time of mounting on the mounting substrate may be damaged. From the viewpoint of the transferability of the electronic component to the mounting substrate, E"1a is preferably 5 MPa or less, and more preferably 3 MPa or less. If the E"1a is too low, the adhesiveness of the electronic component to the first pressure-sensitive adhesive layer This deterioration may cause problems such as misalignment or falling of electronic components. From the viewpoint of the adhesiveness of the electronic component to the first pressure-sensitive adhesive layer, E"1a is preferably 0.01 MPa or more, and more preferably 0.03 MPa or more.

Storage modulus (E'1a) of the first pressure-sensitive adhesive layer at a frequency of 1 Hz and 25° C. by AFM-DMA (Nano Dynamic Mechanical Analysis (nDMA)) , The storage elastic modulus (E'1b) at a frequency of 1 kHz and 25 ° C. and the loss elastic modulus (E" 1a) at a frequency of 1 Hz and 25 ° C. can be adjusted depending on the type, composition, degree of crosslinking, etc. of the constituting pressure-sensitive adhesive.

In the double-sided pressure-sensitive adhesive sheet for transfer of the present invention, it is preferable that the tack force of the first pressure-sensitive adhesive layer to the stainless steel plate (5 mm in diameter) is 10 to 250 gf/φ5 mmSUS. The structure that the said tack force is 10 gf / phi5mmSUS or more is preferable from the viewpoint of adhesiveness of the electronic component to the said 1st adhesive layer and positional accuracy, and 20gf / phi5mmSUS or more is more preferable. On the other hand, the configuration that the above tack force is 250 gf / Φ 5 mmSUS or less is preferable from the viewpoint of transferability to the mounting substrate of electronic parts, and 200 gf / Φ 5 mm SUS or less is more preferable.

The tack force of the first pressure-sensitive adhesive layer to the stainless steel plate (5 mm in diameter) can be adjusted by the type, composition, degree of crosslinking, and additives such as fatty acid esters and fluorine-based surfactants of the pressure-sensitive adhesive constituting the pressure-sensitive adhesive.

In the double-sided pressure-sensitive adhesive sheet for transfer of the present invention, it is preferable that the surface force of the first pressure-sensitive adhesive layer is -500 to -100 μN. The structure in which the said surface force is -500 microN or more is preferable from a viewpoint of adhesiveness of an electronic component to the said 1st adhesive layer and positional accuracy, and -400 microN or more is more preferable. On the other hand, the structure in which the surface force is -100 μN or less is preferable from the viewpoint of the transferability of the electronic component to the mounting substrate, and -150 μN or less is more preferable.

The surface force of the first pressure-sensitive adhesive layer can be adjusted by the type or composition of the pressure-sensitive adhesive, crosslinking degree, and additives such as fatty acid esters and fluorine-based surfactants.

In the double-sided pressure-sensitive adhesive sheet for transfer of the present invention, the thickness t ₁ of the first pressure-sensitive adhesive layer is not particularly limited, but is preferably 1 μm or more, and more preferably 3 μm or more. When the thickness is more than a certain level, the first pressure-sensitive adhesive layer makes it easier to receive electronic parts with high precision, which is preferable. The upper limit of the thickness t ₁ of the first pressure sensitive adhesive layer is not particularly limited, but is preferably 100 μm, more preferably 90 μm, and preferably 80 μm, 70 μm, 60 μm or 50 μm. Moreover, 45 micrometers, 40 micrometers, 35 micrometers, 30 micrometers, 25 micrometers, 20 micrometers, 15 micrometers, or 0 micrometers are more preferable. If the thickness is below a certain level, it is easy to transfer the electronic component to the mounting substrate with high precision, which is preferable.

In the double-sided pressure-sensitive adhesive sheet for transfer of the present invention, the haze (according to JIS K7136) of the first pressure-sensitive adhesive layer is not particularly limited, but is preferably 10% or less, and more preferably 5.0% or less. When the haze is 10% or less, excellent transparency is obtained, and for example, when the double-sided pressure-sensitive adhesive sheet for transfer is affixed to the carrier substrate, the pattern attached on the carrier substrate (for example, a marker indicating the transfer position of the electronic component) can be visually recognized, which is preferable. In addition, the haze is determined by, for example, forming the first pressure-sensitive adhesive layer on the separator and leaving it still in the state (23 ° C., 50% RH) for at least 24 hours, then peeling the separator and removing the slide glass (for example, total light transmittance). What was bonded to 91.8% and haze 0.4%) can be used as a sample, and can be measured using a haze meter (product name "HM-150", manufactured by Murakami Shikisai Kijutsu Genkyujo).

In the double-sided pressure-sensitive adhesive sheet for transfer of the present invention, the total light transmittance (according to JIS K7361-1) of the first pressure-sensitive adhesive layer in the visible light wavelength region is not particularly limited, but is preferably 85% or more, more preferably It is 88% or more. If the total light transmittance is 85% or more, excellent transparency is obtained. For example, when the double-sided pressure-sensitive adhesive sheet for transfer is affixed to the carrier substrate, the pattern attached on the carrier substrate (e.g., a marker indicating the transfer position of the electronic component) ) can be visually recognized, which is preferable. In addition, the above-mentioned total light transmittance is measured by, for example, forming the first pressure-sensitive adhesive layer on the separator and leaving it at least 24 hours in a state (23 ° C., 50% RH), then peeling the separator and sliding glass (for example, total light What was bonded to the thing of transmittance|permeability 91.8% and haze 0.4%) can be used as a sample, and it can measure using a haze meter (product name "HM-150", Murakami Shikisai Kijutsu Genkyujo product).

The pressure-sensitive adhesive composition constituting the first pressure-sensitive adhesive layer is not particularly limited, and examples thereof include silicone pressure-sensitive adhesives, urethane pressure-sensitive adhesives, acrylic pressure-sensitive adhesives, rubber pressure-sensitive adhesives, polyester pressure-sensitive adhesives, polyamide pressure-sensitive adhesives, epoxy pressure-sensitive adhesives, and vinylalkyl ethers. A pressure-sensitive adhesive, a fluorine-based pressure-sensitive adhesive, and the like may be included. Among these, from the viewpoint of being able to receive electronic components with high positioning accuracy without damaging them and having good transferability to a mounting board, silicone-based adhesives, urethane-based adhesives, and acrylic adhesives are preferred, A silicone-based adhesive and a urethane-based adhesive are more preferable, and a silicone-based adhesive is still more preferable.

(Silicone-based adhesive)

The silicone pressure-sensitive adhesive is not particularly limited, and known or commonly used silicone-based pressure-sensitive adhesives can be used, such as addition-type silicone-based pressure-sensitive adhesives, peroxide-curable silicone-based pressure-sensitive adhesives, and condensation-type silicone-based pressure-sensitive adhesives. The silicone pressure-sensitive adhesive may be one-component or two-component. A silicone type adhesive can be used individually or in combination of 2 or more types.

The addition-type silicone-based pressure-sensitive adhesive is generally an addition reaction (hydrosilylation reaction) of an organopolysiloxane having an alkenyl group such as a vinyl group on a silicon atom and an organopolysiloxane having a hydrosilyl group using a platinum compound catalyst such as chloroplatinic acid. ) to create a silicone-based polymer. A peroxide-curable silicone pressure-sensitive adhesive is generally a pressure-sensitive adhesive that cures (crosslinks) organopolysiloxane with a peroxide to form a silicone-based polymer. In addition, the condensation-type silicone-based pressure-sensitive adhesive is generally an pressure-sensitive adhesive that generates a silicone-based polymer by dehydration or dealcoholization between polyorganosiloxanes having a hydrolysable silyl group such as a silanol group or an alkoxysilyl group at the terminal.

Examples of the silicone pressure-sensitive adhesive include silicone pressure-sensitive adhesives containing silicone rubber and silicone resin, from the viewpoint of being easy to control with low tackiness and low tagging properties.

The silicone rubber is not particularly limited as long as it is a silicone-based rubber component, and organopolysiloxanes containing dimethylsiloxane, methylphenylsiloxane, and the like as main structural units can be used, for example. Further, depending on the type of reaction, a silicone rubber having an alkenyl group bonded to a silicon atom (alkenyl group-containing organopolysiloxane; addition reaction type), a silicone rubber having at least a methyl group (peroxide curing type), a silanol group at the end Alternatively, a silicone-based rubber having a hydrolysable alkoxysilyl group (in the case of a condensation type) or the like can be used. In addition, although the weight average molecular weight of organopolysiloxane in silicone rubber is 150,000 or more normally, Preferably it is 280,000 - 1 million, Especially 500,000 - 900,000 are suitable.

The silicone resin is not particularly limited as long as it is a silicone resin used for silicone pressure sensitive adhesives. For example, M units composed of the structural unit "R ₃ Si _1/2 " and Q units composed of the structural unit "SiO ₂ " , a silicone resin composed of an organopolysiloxane composed of a (co)polymer having at least one type of unit selected from a T unit composed of the structural unit "RSiO _3/2 " and a D unit composed of the structural unit "R ₂ SiO", etc. can be heard In addition, R in the said structural unit represents a hydrocarbon group or a hydroxyl group. Examples of the hydrocarbon group include aliphatic hydrocarbon groups (alkyl groups such as methyl and ethyl groups), alicyclic hydrocarbon groups (cycloalkyl groups such as cyclohexyl groups), and aromatic hydrocarbon groups (aryl groups such as phenyl and naphthyl groups). etc. can be mentioned. The ratio (ratio) of the M unit and at least one unit selected from the Q unit, T unit and D unit is, for example, the former/the latter (molar ratio) = 0.3/1 to 1.5/1 (preferably 0.5/1). 1 to 1.3/1) is preferred. Various functional groups, such as a vinyl group, may be introduce|transduced into the organopolysiloxane in this silicone resin as needed. In addition, the functional group to be introduced may be a functional group capable of generating a crosslinking reaction. As the silicone resin, an MQ resin composed of M units and Q units is preferable. Although the weight average molecular weight of organopolysiloxane in silicone resin is 1000 or more normally, Preferably it is 1000-20000, and 1500-10000 are especially suitable.

The mixing ratio of silicone rubber and silicone resin is not particularly limited, but from the viewpoint of low tackiness and low tackiness, it is easy to control, for example, 100 to 220 parts by weight of silicone resin relative to 100 parts by weight of silicone rubber (especially , 120 to 180 parts by weight) is preferred.

In addition, in the silicone pressure-sensitive adhesive containing silicone rubber and silicone resin, the silicone rubber and silicone resin may be in a mixed state in which they are simply mixed, and react with each other to form a condensate (particularly a partial condensate), a crosslinking reaction product, or an addition reaction product. etc.

In addition, silicone pressure-sensitive adhesives containing silicone rubber and silicone resin usually contain a cross-linking agent in order to form a cross-linked structure because of their low tackiness and low tackiness and easy control. Although not particularly limited as such a crosslinking agent, a siloxane-based crosslinking agent (silicone-based crosslinking agent) and a peroxide-based crosslinking agent can be suitably used. A crosslinking agent can be used individually or in combination of 2 or more types.

As the siloxane-based crosslinking agent, for example, a polyorganohydrogensiloxane having two or more hydrogen atoms bonded to silicon atoms in the molecule can be preferably used. In such polyorganohydrogensiloxane, various organic groups other than hydrogen atoms may be bonded to silicon atoms to which hydrogen atoms are bonded. As this organic group, Alkyl groups, such as a methyl group and an ethyl group; In addition to aryl groups such as phenyl groups, halogenated alkyl groups and the like are exemplified, but from the viewpoint of synthesis and handling, a methyl group is preferable. In addition, although the skeleton structure of polyorganohydrogensiloxane may have any of linear, branched, and cyclic skeleton structures, linear is preferable.

Examples of the peroxide-based crosslinking agent include diacyl peroxide, alkyl peroxy ester, peroxy dicarbonate, monoperoxy carbonate, peroxy ketal, dialkyl peroxide, hydroperoxide, ketone peroxide, and the like. can More specifically, for example, benzoyl peroxide, t-butylperoxybenzoate, dicumyl peroxide, t-butylcumyl peroxide, di-t-butyl peroxide, 2,5-dimethyl-2,5-di- t-Butylperoxyhexane, 2,4-dichloro-benzoyl peroxide, di-t-butylperoxy-diisopropylbenzene, 1,1-bis(t-butylperoxy)-3,3,5-trimethyl Cyclohexane, 2,5-dimethyl-2,5-di-t-butylperoxyhexyne-3, etc. are mentioned.

As addition-type silicone-based pressure-sensitive adhesives, for example, trade names "KR-3700", "KR-3701", "X-40-3237-1", "X-40-3240", "X-40-3291-1", " X-40-3306” (above, manufactured by Shin-Etsu Chemical Industry Co., Ltd.) is commercially available. In addition, as peroxide-curable silicone pressure-sensitive adhesives, for example, trade names "KR-100", "KR-101-10", "KR-130" (above, manufactured by Shin-Etsu Chemical Industry Co., Ltd.), etc. are commercially available. .

It is preferable that a curing catalyst such as a platinum catalyst is included in the addition type silicone pressure-sensitive adhesive. As a platinum catalyst, for example, brand name "CAT-PL-50T" (manufactured by Shin-Etsu Chemical Industry Co., Ltd.), brand name "DOWSIL NC-25 Catalyst", "DOWSIL SRX212 Catalyst" (above, Dow Toray Co., Ltd.) ) and the like are commercially available. From the viewpoint of the balance of acceptability of electronic parts of the first pressure sensitive adhesive layer, positional accuracy, transferability to a mounting substrate, tack force, etc., the content of the curing catalyst is a silicone-based polymer as a base polymer (including silicone rubber, silicone resin, etc.) ) is preferably about 0.1 to 10 parts by weight based on 100 parts by weight.

(urethane-based adhesive)

The urethane-based pressure-sensitive adhesive is not particularly limited, and known or conventional urethane-based pressure-sensitive adhesives can be used, and from the viewpoint of low tackiness and easy control, urethane-based pressure-sensitive adhesives containing polyols, polyfunctional isocyanate compounds, and catalysts are preferred. .

As the polyol, any suitable polyol can be employed as long as it is a polyol having two or more hydroxyl groups. Examples of such a polyol include a polyol (diol) having two hydroxyl groups, a polyol (triol) having three hydroxyl groups, a polyol (tetraol) having four hydroxyl groups, and a polyol having 5 hydroxyl groups. A polyol (pentaol) having one, a polyol (hexanol) having six hydroxyl groups, and the like are exemplified. A polyol can be used individually or in combination of 2 or more types.

As the polyol, it is preferable that the number average molecular weight (Mn) preferably includes a polyol of 400 to 20000. The proportion of the polyol having a number average molecular weight (Mn) of 400 to 20000 in the total amount of polyol is preferably 50 to 100% by weight, more preferably 70 to 100% by weight, still more preferably 90 to 100% by weight. % by weight, particularly preferably 95 to 100% by weight, and most preferably substantially 100% by weight. By adjusting the content ratio of the polyol having a number average molecular weight (Mn) of 400 to 20,000 in the polyol within the above range, for example, a urethane-based pressure-sensitive adhesive controlled to have low tackiness and low tackiness can be provided.

As said polyol, polyester polyol, polyether polyol, polycaprolactone polyol, polycarbonate polyol, a castor oil type polyol etc. are mentioned, for example.

As said polyester polyol, it can obtain by esterification reaction of a polyol component and an acid component, for example.

Examples of the polyol component include ethylene glycol, diethylene glycol, 1,3-butanediol, 1,4-butanediol, neopentyl glycol, 3-methyl-1,5-pentanediol, and 2-butyl-2-ethyl- 1,3-propanediol, 2,4-diethyl-1,5-pentanediol, 1,2-hexanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 2 -Methyl-1,8-octanediol, 1,8-decanediol, octadecanediol, glycerin, trimethylolpropane, pentaerythritol, hexanetriol, polypropylene glycol, etc. are mentioned.

Examples of the acid component include succinic acid, methylsuccinic acid, adipic acid, pimeric acid, azelaic acid, sebacic acid, 1,12-dodecanedioic acid, 1,14-tetradecanedioic acid, dimer acid, and 2-methyl-1 ,4-cyclohexanedicarboxylic acid, 2-ethyl-1,4-cyclohexanedicarboxylic acid, terephthalic acid, isophthalic acid, phthalic acid, isophthalic acid, terephthalic acid, 1,4-naphthalenedicarboxylic acid, 4,4 '-biphenyldicarboxylic acid, these acid anhydrides, etc. are mentioned.

Examples of the polyether polyol include water, low molecular weight polyols (propylene glycol, ethylene glycol, glycerin, trimethylolpropane, pentaerythritol, etc.), bisphenols (bisphenol A, etc.), dihydroxybenzene (catechol, resorcin , hydroquinone, etc.) as an initiator, and polyether polyols obtained by addition polymerization of alkylene oxides such as ethylene oxide, propylene oxide, and butylene oxide. Specifically, polyethylene glycol, polypropylene glycol, polytetramethylene glycol etc. are mentioned, for example.

Examples of the polycaprolactone polyol include caprolactone polyester diols obtained by ring-opening polymerization of cyclic ester monomers such as ε-caprolactone and σ-valerolactone.

Examples of the polycarbonate polyol include polycarbonate polyol obtained by subjecting the polyol component and phosgene to a polycondensation reaction; The polyol component and dicarbonate such as dimethyl carbonate, diethyl carbonate, dipropyl carbonate, diisopropyl carbonate, dibutyl carbonate, ethyl butyl carbonate, ethylene carbonate, propylene carbonate, diphenyl carbonate, dibenzyl carbonate, etc. polycarbonate polyols obtained by subjecting esters to transesterification condensation; Copolymerization polycarbonate polyol obtained by using together 2 or more types of the said polyol component; polycarbonate polyols obtained by subjecting the various polycarbonate polyols and carboxyl group-containing compounds to an esterification reaction; polycarbonate polyols obtained by subjecting the various polycarbonate polyols and hydroxyl group-containing compounds to an etherification reaction; Polycarbonate polyol obtained by carrying out the transesterification reaction of the said various polycarbonate polyol and ester compound; polycarbonate polyols obtained by subjecting the various polycarbonate polyols and hydroxyl group-containing compounds to a transesterification reaction; polyester-based polycarbonate polyols obtained by polycondensation of the various polycarbonate polyols and dicarboxylic acid compounds; copolymerized polyether-based polycarbonate polyols obtained by copolymerizing the above various polycarbonate polyols with alkylene oxide; etc. can be mentioned.

As said castor oil-type polyol, the castor oil-type polyol obtained by making castor oil fatty acid and the said polyol component react, for example is mentioned. Specifically, for example, castor oil-based polyols obtained by reacting castor oil fatty acids and polypropylene glycol are exemplified.

As the polyol, it is preferable to use a polyol (triol) having three hydroxyl groups as an essential component from the viewpoints of low tackiness, low tackiness, wettability, etc. to electronic parts of the first pressure-sensitive adhesive layer. The content of the polyol (triol) having three hydroxyl groups is preferably 50 to 100% by weight, more preferably 70 to 100% by weight, based on the total amount of the components constituting the polyol.

As said polyfunctional isocyanate type compound, aliphatic type polyisocyanate, alicyclic type polyisocyanate, aromatic type polyisocyanate compound etc. are mentioned, for example.

Examples of the aliphatic polyisocyanates include trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, pentamethylene diisocyanate, 1,2-propylene diisocyanate, 1,3-butylene diisocyanate, and dodecamethylene diisocyanate. , 2,4,4-trimethylhexamethylene diisocyanate, etc. are mentioned.

Examples of the alicyclic polyisocyanate include 1,3-cyclopentene diisocyanate, 1,3-cyclohexane diisocyanate, 1,4-cyclohexane diisocyanate, isophorone diisocyanate, hydrogenated diphenylmethane diisocyanate, Hydrogenated xylylene diisocyanate, hydrogenated tolylene diisocyanate, hydrogenated tetramethyl xylylene diisocyanate, etc. are mentioned.

Examples of the aromatic polyisocyanate include phenylene diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 2,2'-diphenylmethane diisocyanate, and 4,4'-diphenylmethane diisocyanate. , 4,4'-toluidine diisocyanate, 4,4'-diphenyl ether diisocyanate, 4,4'-diphenyl diisocyanate, 1,5-naphthalene diisocyanate, and xylylene diisocyanate.

Especially, aliphatic polyisocyanate and its modified form are preferable. Compared with other isocyanate-based crosslinking agents, aliphatic polyisocyanates and modified products thereof have a crosslinked structure rich in flexibility, low tackiness and low tackiness, and are easy to control. As aliphatic polyisocyanate and its modified body, hexamethylene diisocyanate and its modified body are especially preferable.

The polyfunctional isocyanate-based compound and the polyol are the isocyanate groups of the polyfunctional isocyanate-based compound and the hydroxyl groups of the polyol, from the viewpoint of low tackiness, low tackiness, and wettability for electronic parts of the first pressure-sensitive adhesive layer body. Equivalent ratio of (NCO/OH) is preferably 1 to 5, more preferably 1.1 to 3, still more preferably 1.2 to 2.

The urethane-based pressure-sensitive adhesive preferably contains a catalyst such as an iron-based compound and/or a tin-based compound. Specifically, tin catalysts such as dibutyltin dilaurate and dioctyltin dilaurate, tris(acetylacetonato)iron, tris(hexane-2,4-dionato)iron, tris(heptane-2,4- dionato)iron, tris(heptane-3,5-dionato)iron, tris(5-methylhexane-2,4-dionato)iron, tris(octane-2,4-dionato)iron, tris(6 -Methylheptane-2,4-dionato)iron, tris(2,6-dimethylheptane-3,5-dionato)iron, tris(nonane-2,4-dionato)iron, tris(nonane-4, 6-dionato)iron, tris(2,2,6,6-tetramethylheptane-3,5-dionato)iron, tris(tridecane-6,8-dionato)iron, tris(1-phenylbutane) -1,3-dionato) iron, tris (hexafluoroacetylacetonato) iron, tris (acetoacetate) iron, tris (acetoacetate-n-propyl) iron, tris (acetoacetate isopropyl) iron, tris (acetoacetate-n-butyl) iron, tris(acetoacetate-sec-butyl) iron, tris(acetoacetate-tert-butyl) iron, tris(methylpropionylacetate)iron, tris(ethylpropionylacetate)iron, Tris(propionylacetate-n-propyl)iron, tris(propionylisopropylacetate)iron, tris(propionylacetate-n-butyl)iron, tris(propionylacetate-sec-butyl)iron, tris(propionylacetate) Iron-acetate-tert-butyl), iron tris(benzylacetoacetate), iron tris(dimethylmalonate), iron tris(diethylmalonate), iron trimethoxy, iron triethoxy, iron triisopropoxy, chlorinating agents Iron-type catalysts, such as ferric iron, are mentioned.

The content (amount used) of the catalyst contained in the urethane-based pressure-sensitive adhesive is preferably 0.002 to 0.5 parts by weight, more preferably 0.005 to 0.3 parts by weight, and still more preferably 0.01 to 0.1 parts by weight, based on 100 parts by weight of the polyol. When it exists in this range, when forming an adhesive layer, the crosslinking reaction speed is fast and the pot life of an adhesive composition also becomes long, and it becomes a preferable aspect.

Further, as the urethane-based pressure-sensitive adhesive, a urethane-based pressure-sensitive adhesive containing a urethane prepolymer is also preferable from the point of being easy to control with low adhesiveness and low tackiness.

Examples of the urethane-based pressure-sensitive adhesive containing a urethane prepolymer include a pressure-sensitive adhesive containing a polyurethane polyol as a urethane prepolymer and a polyfunctional isocyanate-based compound. Urethane prepolymers can be used individually or in combination of 2 or more types. A polyfunctional isocyanate type compound can be used individually or in combination of 2 or more types.

The polyurethane polyol as the urethane prepolymer is preferably obtained by reacting a polyester polyol and a polyether polyol with an organic polyisocyanate compound in the presence or absence of a catalyst.

As the polyester polyol, any suitable polyester polyol can be used. As such a polyester polyol, the polyester polyol obtained by making an acid component and a glycol component react, for example is mentioned. As an acid component, terephthalic acid, adipic acid, azelaic acid, sebacic acid, phthalic anhydride, isophthalic acid, trimellitic acid etc. are mentioned, for example. As the glycol component, for example, ethylene glycol, propylene glycol, diethylene glycol, butylene glycol, 1,6-hexane glycol, 3-methyl-1,5-pentanediol, 3,3'-dimethylolheptane, polyoxy Examples of ethylene glycol, polyoxypropylene glycol, 1,4-butanediol, neopentyl glycol, butylethylpentanediol, and polyol components include glycerin, trimethylolpropane, and pentaerythritol. Other examples of the polyester polyol include polyester polyols obtained by ring-opening polymerization of lactones such as polycaprolactone, poly(β-methyl-γ-valerolactone), and polyvalerolactone.

As molecular weight of polyester polyol, it can use from low molecular weight to high molecular weight. As molecular weight of polyester polyol, number average molecular weight is preferably 500 to 5000. When the number average molecular weight is less than 500, the reactivity increases and there is a possibility that gelation becomes easy. When the number average molecular weight exceeds 5000, there is a possibility that the reactivity becomes low and the cohesive force of polyurethane polyol itself becomes small. The amount of polyester polyol used is preferably 10 to 90 mol% of the polyol constituting the polyurethane polyol.

As the polyether polyol, any suitable polyether polyol can be used. As such a polyether polyol, for example, water, propylene glycol, ethylene glycol, glycerin, low molecular weight polyol such as trimethylolpropane is used as an initiator, and ethylene oxide, propylene oxide, butylene oxide, tetrahydrofuran, etc. and polyether polyols obtained by polymerizing an oxirane compound. Specific examples of such polyether polyols include polyether polyols having two or more functional groups such as polypropylene glycol, polyethylene glycol, and polytetramethylene glycol.

As molecular weight of polyether polyol, it can use from low molecular weight to high molecular weight. As the molecular weight of the polyether polyol, the number average molecular weight is preferably 1000 to 5000. When the number average molecular weight is less than 1000, there is a possibility that the reactivity increases and gelation becomes easy. When the number average molecular weight exceeds 5000, there is a possibility that the reactivity becomes low and the cohesive force of polyurethane polyol itself becomes small. The amount of polyether polyol used is preferably 20 to 80 mol% of the polyol constituting the polyurethane polyol.

Polyether polyol, if necessary, partially contains glycols such as ethylene glycol, 1,4-butanediol, neopentyl glycol, butylethylpentanediol, glycerin, trimethylolpropane and pentaerythritol, ethylenediamine and N-amino It can be used in combination by substituting with polyhydric amines such as ethylethanolamine, isophoronediamine, and xylylenediamine.

As the polyether polyol, only a bifunctional polyether polyol may be used, and polyether polyols having a number average molecular weight of 1000 to 5000 and having at least 3 or more hydroxyl groups in one molecule may be partially or entirely used. As the polyether polyol, when a part or all of a polyether polyol having an average molecular weight of 1000 to 5000 and having at least 3 or more hydroxyl groups in one molecule is used, the balance between adhesive force and re-peelability can be improved. In such a polyether polyol, if the number average molecular weight is less than 1000, the reactivity increases and there is a possibility that gelation becomes easy. In addition, in such a polyether polyol, when the number average molecular weight exceeds 5000, there is a possibility that the reactivity becomes low and the cohesive force of polyurethane polyol itself becomes small. The number average molecular weight of such polyether polyol is more preferably 2500 to 3500.

As the organic polyisocyanate compound, any suitable organic polyisocyanate compound can be used. As such an organic polyisocyanate compound, aromatic polyisocyanate, aliphatic polyisocyanate, aromatic aliphatic polyisocyanate, alicyclic polyisocyanate, etc. are mentioned, for example.

As aromatic polyisocyanate, for example, 1,3-phenylene diisocyanate, 4,4'-diphenyl diisocyanate, 1,4-phenylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 2,4-tolyl Rendiisocyanate, 2,6-tolylene diisocyanate, 4,4'-toluidine diisocyanate, 2,4,6-triisocyanate toluene, 1,3,5-triisocyanate benzene, dianisidine diisocyanate, 4,4'- Diphenyl ether diisocyanate, 4,4', 4"-triphenylmethane triisocyanate, etc. are mentioned.

Examples of aliphatic polyisocyanates include trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, pentamethylene diisocyanate, 1,2-propylene diisocyanate, 2,3-butylene diisocyanate, and 1,3-butylene diisocyanate. Isocyanate, dodecamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, etc. are mentioned.

As aromatic aliphatic polyisocyanate, for example, ω,ω'-diisocyanate-1,3-dimethylbenzene, ω,ω'-diisocyanate-1,4-dimethylbenzene, ω,ω'-diisocyanate-1,4 -Diethylbenzene, 1,4-tetramethylxylylene diisocyanate, 1,3-tetramethylxylylene diisocyanate, etc. are mentioned.

As alicyclic polyisocyanate, for example, 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate, 1,3-cyclopentane diisocyanate, 1,3-cyclohexane diisocyanate, 1,4- Cyclohexane diisocyanate, methyl-2,4-cyclohexane diisocyanate, methyl-2,6-cyclohexane diisocyanate, 4,4'-methylenebis(cyclohexylisocyanate), 1,4-bis(isocyanato methyl)cyclohexane, 1,4-bis(isocyanatomethyl)cyclohexane, and the like.

As the organic polyisocyanate compound, a trimethylolpropane adduct, a biuret compound reacted with water, a trimer having an isocyanurate ring, and the like can be used together.

Arbitrary suitable catalysts can be used as a catalyst that can be used when obtaining polyurethane polyol. Examples of such catalysts include tertiary amine compounds and organometallic compounds.

Examples of the tertiary amine compound include triethylamine, triethylenediamine, and 1,8-diazabicyclo (5,4,0)-undecene-7 (DBU).

As an organometallic compound, a tin-type compound, a non-tin-type compound, etc. are mentioned, for example.

As a tin compound, for example, dibutyltin dichloride, dibutyltin oxide, dibutyltin dibromide, dibutyltin dimaleate, dibutyltin dilaurate (DBTDL), dibutyltin diacetate, dibutyl Tin sulfide, tributyl tin sulfide, tributyl tin oxide, tributyl tin acetate, triethyl tin ethoxide, tributyl tin ethoxide, dioctyl tin oxide, tributyl tin chloride, tributyl tin trichloroacetate , 2-ethyl hexanoate tin, etc. are mentioned.

Examples of non-tin compounds include titanium compounds such as dibutyl titanium dichloride, tetrabutyl titanate, and butoxy titanium trichloride; lead-based compounds such as lead oleate, lead 2-ethylhexanoate, lead benzoate, and lead naphthenate; iron-based compounds such as iron 2-ethylhexanoate and iron acetylacetonate; cobalt-based compounds such as cobalt benzoate and cobalt 2-ethylhexanoate; zinc-based compounds such as zinc naphthenate and zinc 2-ethylhexanoate; zirconium-based compounds such as zirconium naphthenate; etc. can be mentioned.

When a catalyst is used to obtain a polyurethane polyol, in a system in which two types of polyols, polyester polyol and polyether polyol exist, the reactivity is different, so in a single catalyst system, gelation or the reaction solution becomes cloudy. prone to problems Then, when obtaining a polyurethane polyol, by using two types of catalysts, it becomes easy to control the reaction rate, the selectivity of the catalyst, etc., and these problems can be solved. Examples of the combination of these two types of catalysts include tertiary amine/organometallic, tin-based/non-tin-based, and tin-based/tin-based catalysts, preferably tin-based/tin-based, and more preferably di It is a combination of butyltin dilaurate and 2-ethyltin hexanoate. The compounding ratio, in weight ratio, of tin 2-ethylhexanoate/dibutyltin dilaurate is preferably less than 1, more preferably 0.2 to 0.6. If the compounding ratio is 1 or more, there is a concern that gelation becomes easy due to the balance of catalytic activity.

When using a catalyst when obtaining polyurethane polyol, the amount of catalyst used is preferably 0.01 to 1.0% by weight relative to the total amount of polyester polyol, polyether polyol, and organic polyisocyanate compound.

When using a catalyst when obtaining polyurethane polyol, the reaction temperature is preferably less than 100°C, and more preferably 85°C to 95°C. When the temperature is 100°C or higher, there is a fear that control of the reaction rate and the crosslinking structure may become difficult, and it may become difficult to obtain a polyurethane polyol having a predetermined molecular weight.

When obtaining polyurethane polyol, it is not necessary to use a catalyst. In that case, the reaction temperature is preferably 100°C or higher, more preferably 110°C or higher. Moreover, when obtaining a polyurethane polyol in the absence of a catalyst, it is preferable to make it react for 3 hours or more.

As a method of obtaining polyurethane polyol, for example, 1) a method in which polyester polyol, polyether polyol, catalyst, and organic polyisocyanate are put into a flask, 2) polyester polyol, polyether polyol, and catalyst are put into a flask, The method of adding organic polyisocyanate dropwise is mentioned. As a method of obtaining polyurethane polyol, the method of 2) is preferable in controlling the reaction.

When obtaining polyurethane polyol, any suitable solvent can be used. As such a solvent, methyl ethyl ketone, ethyl acetate, toluene, xylene, acetone etc. are mentioned, for example. Among these solvents, toluene is preferred.

As a polyfunctional isocyanate type compound, what was mentioned above can be used.

As a method for producing a polyurethane-based composition obtained from a composition containing a urethane prepolymer, any suitable production method can be employed as long as it is a method for producing a polyurethane-based resin composition using a so-called "urethane prepolymer" as a raw material.

(Acrylic adhesive)

The acrylic pressure-sensitive adhesive is not particularly limited, and known or commonly used acrylic pressure-sensitive adhesives can be used. there is.

The acrylic polymer is a polymer containing a structural unit derived from an acrylic monomer (a monomer component having a (meth)acryloyl group in a molecule) as a structural unit of the polymer. It is preferable that the said acrylic polymer is a polymer containing the most structural unit derived from (meth)acrylic acid ester by weight ratio. In addition, an acryl-type polymer can be used individually or in combination of 2 or more types. In addition, in this specification, "(meth)acryl" shows "acryl" and/or "methacryl" (either one or both of "acryl" and "methacryl"), and the others are the same.

As said (meth)acrylic acid ester, hydrocarbon group containing (meth)acrylic acid ester is mentioned, for example. Examples of hydrocarbon group-containing (meth)acrylic acid esters include (meth)acrylic acid alkyl esters, (meth)acrylic acid cycloalkyl esters, and (meth)acrylic acid aryl esters. Examples of the (meth)acrylic acid alkyl ester include (meth)acrylic acid methyl ester, ethyl ester, propyl ester, isopropyl ester, butyl ester, isobutyl ester, s-butyl ester, t-butyl ester, pentyl ester, Isopentyl ester, hexyl ester, heptyl ester, octyl ester, 2-ethylhexyl ester, isooctyl ester, nonyl ester, decyl ester, isodecyl ester, undecyl ester, dodecyl ester (lauryl ester), tridecyl ester, Tetradecyl ester, hexadecyl ester, octadecyl ester, eicosyl ester, etc. are mentioned. Examples of the (meth)acrylic acid cycloalkyl ester include cyclopentyl ester and cyclohexyl ester of (meth)acrylic acid. Examples of the (meth)acrylic acid aryl ester include phenyl ester and benzyl ester of (meth)acrylic acid.

These hydrocarbon group-containing (meth)acrylic acid esters can be used alone or in combination of two or more. From the viewpoint that basic properties such as adhesiveness by hydrocarbon group-containing (meth)acrylic acid ester are appropriately expressed in the first adhesive layer and easily controlled with low adhesiveness and low tackiness, the total monomer components for forming the acrylic polymer The ratio of the hydrocarbon group-containing (meth)acrylic acid ester in the composition is preferably 40% by weight or more, and more preferably 60% by weight or more.

The acrylic polymer may contain structural units derived from other monomer components copolymerizable with the hydrocarbon group-containing (meth)acrylic acid ester for the purpose of modifying cohesive force, heat resistance, tackiness, and the like. Examples of the other monomer components include a carboxy group-containing monomer, an acid anhydride monomer, a hydroxyl group-containing monomer, a glycidyl group-containing monomer, a sulfonic acid group-containing monomer, a phosphoric acid group-containing monomer, a functional group-containing monomer such as acrylamide and acrylonitrile, and vinyl An ester type monomer etc. are mentioned. Examples of the carboxy group-containing monomer include acrylic acid, methacrylic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid. Examples of the acid anhydride monomer include maleic anhydride and itaconic anhydride. Examples of the hydroxy group-containing monomer include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, ( 8-hydroxyoctyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, 12-hydroxylauryl (meth)acrylate, (4-hydroxymethylcyclohexyl)methyl (meth)acrylate, and the like. . Examples of the glycidyl group-containing monomer include glycidyl (meth)acrylate and methylglycidyl (meth)acrylate. Examples of the sulfonic acid group-containing monomer include styrenesulfonic acid, allylsulfonic acid, 2-(meth)acrylamide-2-methylpropanesulfonic acid, (meth)acrylamidopropanesulfonic acid, sulfopropyl (meth)acrylate, (meth) Acryloyloxy naphthalene sulfonic acid etc. are mentioned. As said phosphoric acid group containing monomer, 2-hydroxyethyl acryloyl phosphate etc. are mentioned, for example. Examples of the vinyl ester monomer include vinyl acetate, vinyl propionate, vinyl butyrate, vinyl pivalate, vinyl cyclohexanecarboxylate, and vinyl benzoate. These other monomer components can be used alone or in combination of two or more. From the viewpoint that basic properties such as adhesiveness by hydrocarbon group-containing (meth)acrylic acid ester are appropriately expressed in the first adhesive layer and easily controlled with low adhesiveness and low tackiness, the total monomer components for forming the acrylic polymer The total proportion of the other monomer components in the composition is preferably 60% by weight or less, and more preferably 40% by weight or less.

The acrylic polymer may contain a structural unit derived from a polyfunctional monomer copolymerizable with a monomer component forming the acrylic polymer in order to form a crosslinked structure in the polymer backbone. Examples of the polyfunctional monomer include hexanediol di(meth)acrylate, (poly)ethylene glycol di(meth)acrylate, (poly)propylene glycol di(meth)acrylate, and neopentyl glycol di(meth)acrylate. rate, pentaerythritol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, epoxy(meth)acrylate ( For example, monomers having a (meth)acryloyl group and other reactive functional groups in the molecule, such as polyglycidyl (meth)acrylate), polyester (meth)acrylate, and urethane (meth)acrylate, etc. there is. These polyfunctional monomers can be used alone or in combination of two or more. From the viewpoint that basic properties such as adhesiveness by hydrocarbon group-containing (meth)acrylic acid ester are appropriately expressed in the first adhesive layer and easily controlled with low adhesiveness and low tackiness, the total monomer components for forming the acrylic polymer As for the ratio of the said polyfunctional monomer in, 40 weight% or less is preferable, More preferably, it is 30 weight% or less.

An acrylic polymer is obtained by subjecting one or more types of monomer components containing an acrylic monomer to polymerization. Examples of the polymerization method include solution polymerization, emulsion polymerization, bulk polymerization, and suspension polymerization.

The weight average molecular weight of the acrylic polymer is preferably 100,000 or more, more preferably 200,000 to 3,000,000. When the weight average molecular weight is 100,000 or more, there tends to be few low-molecular-weight substances in the pressure-sensitive adhesive layer, and contamination of electronic parts and the like can be further suppressed.

The acrylic pressure-sensitive adhesive composition forming the first pressure-sensitive adhesive layer may contain a crosslinking agent. For example, the low-molecular-weight substance in the first pressure-sensitive adhesive layer can be further reduced by crosslinking the acrylic polymer. Moreover, it is possible to increase the weight average molecular weight of the acrylic polymer and control it with low adhesiveness and low adhesiveness. Examples of the crosslinking agent include polyisocyanate compounds, epoxy compounds, polyol compounds (such as polyphenol compounds), aziridine compounds, and melamine compounds, and isocyanate crosslinking agents and/or epoxy crosslinking agents are preferable. When a crosslinking agent is used, the amount used is preferably about 10 parts by weight or less, more preferably 0.1 to 10 parts by weight, based on 100 parts by weight of the acrylic polymer.

As an isocyanate type crosslinking agent, aliphatic isocyanates, alicyclic isocyanates, and aromatic isocyanates are mentioned, for example. As aliphatic isocyanate, trimethylene diisocyanate, butylene diisocyanate, hexamethylene diisocyanate, and dimer acid diisocyanate are mentioned, for example. Examples of the alicyclic isocyanates include cyclopentylene diisocyanate, cyclohexylene diisocyanate, isophorone diisocyanate, and 1,3-bis(isocyanatomethyl)cyclohexane. As aromatic isocyanates, 2,4-tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, and xylylene diisocyanate are mentioned, for example. In addition, as an isocyanate-based crosslinking agent, a trimethylolpropane adduct of tolylene diisocyanate (trade name "Coronate L", manufactured by Tosoh Co., Ltd.) or an isocyanuric compound of hexamethylene diisocyanate (trade name "Coronate HX", Tosoh ( Note) can also be mentioned.

Examples of the epoxy-based crosslinking agent (polyfunctional epoxy compound) include N,N,N',N'-tetraglycidyl-m-xylenediamine, diglycidylaniline, and 1,3-bis(N,N- Diglycidylaminomethyl) cyclohexane, 1,6-hexanediol diglycidyl ether, neopentyl glycol diglycidyl ether, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, polyethylene glycol di Glycidyl ether, polypropylene glycol diglycidyl ether, sorbitol polyglycidyl ether, glycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, polyglycerol polyglycidyl ether, sorbitan polyglycidyl Dyl ether, trimethylolpropane polyglycidyl ether, adipic acid diglycidyl ester, o-phthalic acid diglycidyl ester, triglycidyl-tris (2-hydroxyethyl) isocyanurate, resorcin diglycidyl cydyl ether and bisphenol-S-diglycidyl ether, as well as epoxy resins having two or more epoxy groups in the molecule. As an epoxy-type crosslinking agent marketed, "Tetrade C" by Mitsubishi Gas Chemical Co., Ltd. is mentioned, for example.

It is preferable that the adhesive composition which comprises a 1st adhesive layer contains an easy peeling agent. By including the light release agent, a WBL (Weak Boundary Layer) is formed on the surface of the first pressure-sensitive adhesive layer, making it easy to control with low adhesiveness and low tackiness.

The easy-release agent is not particularly limited, and known easy-release agents can be used without limitation, and examples thereof include silicone-based release agents, fluorine-based surfactants, and aliphatic esters, which are used alone or in combination of two or more. can be used

Although it does not specifically limit as said silicone type release agent, For example, a thermosetting silicone type release agent, an ionizing radiation curable silicone type release agent, etc. are mentioned. Further, the silicone-based release agent may be either a non-solvent type that does not contain a solvent or a solvent type that is dissolved or dispersed in an organic solvent. In addition, a silicone type release agent can be used individually or in combination of 2 or more types.

Although it does not specifically limit as said thermosetting silicone type release agent, What contains organohydrogen polysiloxane and organopolysiloxane which has an aliphatic unsaturated group is preferable. In addition, the silicone-based release agent is preferably a heat-addition reaction-curable silicone-based release agent that is cured by crosslinking by a heat addition reaction.

The heat addition reaction-curable silicone-based release agent is not particularly limited, but includes a polysiloxane having a hydrogen atom (H) bonded to a silicon atom (Si) in the molecule (polysiloxane containing a Si-H group), and a Si-H bond (Si A release agent containing a polysiloxane (Si-H group-reactive polysiloxane) containing a functional group (Si-H group-reactive functional group) having reactivity with respect to a covalent bond between H and H) is preferably used. In addition, this release agent cures by crosslinking by addition reaction of the Si-H group and the Si-H group-reactive functional group.

In the Si-H group-containing polysiloxane, Si bonded to H may be either Si in the main chain or Si in the side chain. The Si-H group-containing polysiloxane is preferably a polysiloxane containing two or more Si-H groups in the molecule. As the polysiloxane containing two or more Si-H groups, dimethylhydrogensiloxane-based polymers such as poly(dimethylsiloxane-methylsiloxane) are preferably exemplified.

In addition, as the Si-H group-reactive polysiloxane, the Si-H group-reactive functional group or the side chain containing such a functional group is Si forming the main chain (skeleton) of the siloxane-based polymer (eg, Si at the main chain terminal, inside the main chain). The polysiloxane of the aspect bonded to Si) of is preferably mentioned. Among them, polysiloxanes in which a Si-H group-reactive functional group is directly bonded to Si in the main chain are preferred. Further, as the Si-H group-reactive polysiloxane, polysiloxanes containing two or more Si-H group-reactive functional groups in the molecule are also preferably used.

As a Si-H group-reactive functional group in the said Si-H group-reactive polysiloxane, alkenyl groups, such as a vinyl group and a hexenyl group, etc. are mentioned, for example. Further, as the siloxane-based polymer forming the main chain portion in the Si-H group-reactive polysiloxane, for example, polydialkylsiloxanes such as polydimethylsiloxane, polydiethylsiloxane, and polymethylethylsiloxane (two alkyl groups are the same may or may not be different); polyalkylarylsiloxanes; Poly(dimethylsiloxane methylsiloxane), a polymer obtained by polymerizing a plurality of Si-containing monomers, and the like are exemplified. Especially, as a siloxane type polymer which forms a principal chain part, polydimethylsiloxane is preferable.

In particular, the heat addition reaction curable silicone-based release agent is a heat addition reaction-curable silicone-based release agent containing polysiloxane containing two or more Si-H groups in its molecule and polysiloxane containing two or more Si-H group reactive functional groups in its molecule. it is desirable

Further, the ionizing radiation-curable silicone-based release agent is not particularly limited, but preferably includes a UV-curable silicone-based release agent that undergoes a crosslinking reaction and is cured by ultraviolet (UV) irradiation.

The UV-curable silicone-based release agent is a release agent that is cured by chemical reactions such as cationic polymerization, radical polymerization, radical addition polymerization, and hydrosilylation reaction by UV irradiation. The UV curable silicone release agent is particularly preferably a UV curable silicone release agent that is cured by cationic polymerization.

The cationic polymerization type UV-curable silicone release agent is not particularly limited, but at least two epoxy groups form the main chain (skeleton) of the siloxane-based polymer Si (eg, Si at the main chain terminal, Si inside the main chain), and / or a release agent containing an epoxy group-containing polysiloxane bonded to Si included in the side chain directly or through a divalent group (alkylene group such as methylene group and ethylene group; alkyleneoxy group such as ethyleneoxy group and propyleneoxy group, etc.) can be preferably mentioned. The bonding mode of these at least two epoxy groups to Si may be the same or different. That is, a release agent containing polysiloxane containing two or more epoxy group-containing side chains of one type or two or more types is preferably used. Examples of the epoxy group-containing side chain include glycidyl group, glycidoxy group (glycidyloxy group), 3,4-epoxycyclohexyl group, and 2,3-epoxycyclopentyl group. The epoxy group-containing polysiloxane may be linear, branched or a mixture thereof.

In particular, in the double-sided pressure-sensitive adhesive tape for transfer of the present invention, from the viewpoint of easy control of the first pressure-sensitive adhesive layer with low tackiness and low tackiness, it is preferable to include a thermosetting silicone-based release agent in the silicone-based pressure-sensitive adhesive, and a heat addition reaction curable silicone-based release agent. It is more preferable to include.

When the first pressure-sensitive adhesive layer in the double-sided pressure-sensitive adhesive tape for transfer of the present invention contains a silicone-based pressure-sensitive adhesive, the content of the silicone-based release agent is not particularly limited, but is 0.5 part by weight or more based on 100 parts by weight of the silicone-based polymer as the base polymer. It is preferably 100 parts by weight or less. When the content is 0.5 parts by weight or more, it is easy to obtain the effect of easily controlling the first pressure-sensitive adhesive layer with low tackiness and low tackiness, more preferably 1 part by weight or more, still more preferably 3 parts by weight or more. am. In addition, when the content is 100 parts by weight or less, it is easy to suppress the problem that sufficient adhesiveness is not obtained and the receipt of electronic parts becomes difficult, more preferably 30 parts by weight or less, and still more preferably 25 parts by weight. below

By using the above fluorine-based surfactant as an easy peeling agent, the light peeling effect due to the low surface free energy of the fluorine site can be exhibited.

Examples of the fluorine-based surfactant include, but are not particularly limited to, fluorine-based oligomers, perfluorobutanesulfonic acid salts, perfluoroalkyl group-containing carboxylate salts, hexafluoropentane trimer derivative-containing sulfonic acid salts, and hexafluoropentane trimer derivatives. carboxylic acid salts containing hexafluoropentane trimer derivatives, quaternary ammonium salts containing hexafluoropentane trimer derivatives, betaines containing hexafluoropentane trimer derivatives, polyoxyethylene ethers containing hexafluoropentane trimer derivatives, and the like. Among them, fluorine-based oligomers desirable. In addition, fluorochemical surfactants can be used individually or in combination of 2 or more types.

As a specific example of the said fluorochemical surfactant, for example, as a commercial item, a brand name "Megafac F-114", "Megafac F-410" (above, DIC Co., Ltd. product), a brand name "Suplon S-211", " Suplon S-221”, “Suplon S-231”, “Suplon S-232”, “Suplon S-233”, “Suplon S-241”, “Suplon S-242”, “Suplon S-242” S-243", "Suplon S-420" (above, manufactured by AGC Seimi Chemical Co., Ltd.), trade names "Ptergent 100", "Ptergent 100C", "Ptergent 110", "Ptergent 150", 「Phtergent 150CH」, 「Ptergent 300」, 「Ptergent 310」, 「Ptergent 320」, 「Ptergent 400SW」, 「Ptergent 251」, 「Ptergent 212M」, 「Ptergent 215M」, 「Ptergent 215M」 「Ptergent 250」, 「Ptergent 209F」, 「Ptergent 222F」, 「Ptergent 245F」, 「Ptergent 208G」, 「Ptergent 218GL」, 「Ptergent 240G」, 「Ptergent 212P」, 「Ptergent 220P ”, “Putergent 228P”, “Putergent FTX-218”, “Putergent DFX-18 (manufactured by Neos Co., Ltd.), and the like. These compounds may be used alone or in combination of two or more.

The weight average molecular weight (Mw) of the fluorine-based oligomer is preferably 3500 or more, more preferably 5000 or more, still more preferably 10000 or more, and particularly preferably 20000 or more. If the weight average molecular weight of the said fluorine-type oligomer is 3500 or more, it will become easy to control low adhesiveness and low adhesiveness. In addition, when the weight average molecular weight is 20000 or more, foaming at the time of blending of the pressure-sensitive adhesive (composition) can be suppressed and the appearance after application of the pressure-sensitive adhesive is excellent, so it is preferable. Moreover, as an upper limit of the weight average molecular weight (Mw) of the said fluorine-type oligomer, 200,000 is preferable and 100,000 or less are more preferable. By setting the upper limit to 200,000, the fluorine-based oligomer tends to be unevenly distributed on the surface, and the light peeling effect is more easily exhibited, which is preferable.

In addition, as the said fluorine-type oligomer, for example, as a commercial item, the trade name "Megafac F-251", "Megafac F-253", "Megafac F-281", "Megafac F-410", "Megafac F" -430”, “Megapack F-444”, “Megapack F-477”, “Megapack F-510”, “Megapack F-511”, “Megapack F-551”, “Megapack F-552” ”, “Megapack F-553”, “Megapack F-554”, “Megapack F-555”, “Megapack F-556”, “Megapack F-557”, “Megapack F-558”, “Megapack F-559”, “Megapack F-560”, “Megapack F-561”, “Megapack F-562”, “Megapack F-563”, “Megapack F-565”, “Megapack” "Megapack F-568", "Megapack F-569", "Megapack F-570", "Megapack F-571", "Megapack F-572 (above, manufactured by DIC Co., Ltd.), trade name "Suplon" S-611", "Suplon S-651", "Suplon S-386 (above, manufactured by AGC Seimi Chemical Co., Ltd.), trade names "Ptergent 610FM", "Ptergent 710FL", "Ptergent 710FM" , “Putergent 710FS”, “Putergent 730FL”, “Putergent 730LM (manufactured by Neos Co., Ltd.), and the like. These compounds may be used alone or in combination of two or more.

When the first pressure-sensitive adhesive layer in the double-sided pressure-sensitive adhesive tape for transfer according to the present invention contains a fluorochemical surfactant, the content of the fluorochemical surfactant is not particularly limited, but is 0.01 weight based on 100 parts by weight of the silicone polymer as the base polymer. It is preferable that it is 5 parts by weight or more and 5 parts by weight or less. When the content is 0.01 part by weight or more, it is easy to obtain the effect of easily controlling the first pressure-sensitive adhesive layer with low tackiness and low tackiness, more preferably 0.05 part by weight or more, still more preferably 0.1 part by weight or more. am. In addition, when the content is 5 parts by weight or less, it is easy to suppress the problem that sufficient adhesiveness is not obtained and the acceptance of electronic parts becomes difficult, and also from the viewpoint of suppressing a decrease in transparency, more preferably 3 parts by weight or less, and more preferably 2 parts by weight or less.

When the pressure-sensitive adhesive composition constituting the first pressure-sensitive adhesive layer contains a fatty acid ester, low-adhesion, low tackiness, and wettability to electronic parts of the first pressure-sensitive adhesive layer can be expected.

Examples of the fatty acid ester include polyoxyethylene bisphenol A laurate, butyl stearate, 2-ethylhexyl palmitate, 2-ethylhexyl stearate, monoglyceride behenate, and cetyl 2-ethylhexanoate. , isopropyl myristate, isopropyl palmitate, cholesteryl isostearate, lauryl methacrylate, methyl coconut fatty acid, methyl laurate, methyl oleate, methyl stearate, myristyl myristate, myristic acid Octyldodecyl, pentaerythritol monooleate, pentaerythritol monostearate, pentaerythritol tetrapalmitate, stearyl stearate, isotridecyl stearate, 2-ethylhexanoate triglyceride, butyl laurate, oleic acid Octyl, tridecyl isononanoate, etc. are mentioned. Fatty acid ester can be used individually or in combination of 2 or more types.

The content of the fatty acid ester contained in the urethane-based pressure-sensitive adhesive composition is, from the viewpoint of the low tackiness, low tackiness, wettability or staining property to the adherend to the electronic parts of the first pressure-sensitive adhesive layer, for example, relative to 100 parts by weight of polyol, 1 to 50 parts by weight is preferred, 2 to 40 parts by weight is more preferred, and 3 to 30 parts by weight is still more preferred.

When the pressure-sensitive adhesive composition constituting the first pressure-sensitive adhesive layer contains an easy-to-release agent, the content (total amount) of the first pressure-sensitive adhesive layer is from the viewpoint of low-adhesion, low tackiness, wettability and contamination to electronic parts of the first pressure-sensitive adhesive layer. , for example, with respect to 100 parts by weight of the base polymer, 0.1 part by weight or more is preferable, 1 part by weight or more is more preferable, and 3 parts by weight or more is still more preferable. From the viewpoint of preventing coloring of the first pressure sensitive adhesive layer, the amount is preferably 50 parts by weight or less, more preferably 30 parts by weight or less, and still more preferably 10 parts by weight or less.

Examples of the ultraviolet absorber include, but are not particularly limited to, triazine-based ultraviolet absorbers, benzotriazole-based ultraviolet absorbers, benzophenone-based ultraviolet absorbers, oxybenzophenone-based ultraviolet absorbers, salicylate-based ultraviolet absorbers, and cyanoacrylate-based ultraviolet absorbers. A water absorbent etc. are mentioned, These can be used individually or in combination of 2 or more types. Among these, a benzotriazole-based ultraviolet absorber and a triazine-based ultraviolet absorber are preferable from the viewpoint of having a high ability to absorb ultraviolet rays at a wavelength of around 250 nm.

As a triazine-based ultraviolet absorber having two or less hydroxyl groups in one molecule, specifically, 2,4-bis-[{4-(4-ethylhexyloxy)-4-hydroxy}-phenyl]-6- (4-methoxyphenyl)-1,3,5-triazine (trade name "Tinosorb S", manufactured by BASF), 2,4-bis[2-hydroxy-4-butoxyphenyl]-6-(2, 4-dibutoxyphenyl) -1,3,5-triazine (trade name "TINUVIN460", manufactured by BASF), 2-(4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine Reaction product of -2-yl)-5-hydroxyphenyl and [(C ₁₀ -C ₁₆ (mainly C ₁₂ -C ₁₃ )alkyloxy)methyl]oxirane (trade name “TINUVIN400” manufactured by BASF), 2-[ 4,6-bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl]-5-[3-(dodecyloxy)-2-hydroxypropoxy]phenol), 2 Reaction product of -(2,4-dihydroxyphenyl)-4,6-bis-(2,4-dimethylphenyl)-1,3,5-triazine and (2-ethylhexyl)-glycidic acid ester ( Trade name "TINUVIN405", manufactured by BASF), 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-[(hexyl)oxy]-phenol (trade name "TINUVIN1577", BASF manufactured), 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-[2-(2-ethylhexanoyloxy)ethoxy]-phenol (trade name “ADK STAB LA46”, manufactured by ADEKA), 2-(2-hydroxy-4-[1-octyloxycarbonylethoxy]phenyl)-4,6-bis(4-phenylphenyl)-1,3,5-triazine (trade name "TINUVIN479", manufactured by BASF); and the like.

In addition, as a benzotriazole-based ultraviolet absorber having one benzotriazole skeleton in one molecule, 2-(2H-benzotriazol-2-yl)-6-(1-methyl-1-phenylethyl)-4-( 1,1,3,3-tetramethylbutyl)phenol (trade name "TINUVIN 928", manufactured by BASF), 2-(2-hydroxy-5-tert-butylphenyl)-2H-benzotriazole (trade name "TINUVIN PS ", manufactured by BASF), benzenepropanoic acid and 3-(2H-benzotriazol-2-yl)-5-(1,1-dimethylethyl)-4-hydroxy (C _7-9 branched chain and straight chain alkyl) Ester compound (trade name "TINUVIN384-2", manufactured by BASF), 2-(2H-benzotriazol-2-yl)-4,6-bis(1-methyl-1-phenylethyl)phenol (trade name "TINUVIN900", BASF), 2-(2H-benzotriazol-2-yl)-6-(1-methyl-1-phenylethyl)-4-(1,1,3,3-tetramethylbutyl)phenol (trade name "TINUVIN928", manufactured by BASF), reaction product of methyl-3-(3-(2H-benzotriazol-2-yl)-5-t-butyl-4-hydroxyphenyl)propionate/polyethylene glycol 300 (trade name "TINUVIN1130", manufactured by BASF), 2-(2H-benzotriazol-2-yl)-p-cresol (trade name "TINUVIN P", manufactured by BASF), 2(2H-benzotriazol-2-yl)-4 -6-bis(1-methyl-1-phenylethyl)phenol (trade name "TINUVIN234", manufactured by BASF), 2-[5-chloro(2H)-benzotriazol-2-yl]-4-methyl-6- (tert-butyl)phenol (trade name "TINUVIN326", manufactured by BASF), 2-(2H-benzotriazol-2-yl)-4,6-di-tert-pentylphenol (trade name "TINUVIN328", manufactured by BASF), 2-(2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)phenol (trade name "TINUVIN329", manufactured by BASF), methyl 3-(3-(2H-benzo) Reaction product of triazol-2-yl)-5-tert-butyl-4-hydroxyphenyl)propionate and polyethylene glycol 300 (trade name "TINUVIN213", manufactured by BASF), 2-(2H-benzotriazole-2 -yl)-6-dodecyl-4-methylphenol (trade name "TINUVIN571", manufactured by BASF), 2-[2-hydroxy-3-(3,4,5,6-tetrahydrophthalimidemethyl)- 5-methylphenyl] benzotriazole (trade name "Sumisorb 250", manufactured by Sumitomo Chemical Industry Co., Ltd.); and the like.

Examples of the benzophenone-based ultraviolet absorbers (benzophenone-based compounds) and oxybenzophenone-based ultraviolet absorbers (oxybenzophenone-based compounds) include, for example, 2,4-dihydroxybenzophenone, 2-hydroxy-4- Methoxybenzophenone, 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid (anhydrous and trihydrate), 2-hydroxy-4-octyloxybenzophenone, 4-dodecyloxy-2-hydroxybenzo phenone, 4-benzyloxy-2-hydroxybenzophenone, 2,2',4,4'-tetrahydroxybenzophenone, 2,2'-dihydroxy-4,4-dimethoxybenzophenone, etc. can

Examples of the salicylic acid ester ultraviolet absorber (salicylic acid ester compound) include phenyl-2-acryloyloxybenzoate, phenyl-2-acryloyloxy-3-methylbenzoate, and phenyl-2-acryloyloxybenzoate. Iloxy-4-methylbenzoate, phenyl-2-acryloyloxy-5-methylbenzoate, phenyl-2-acryloyloxy-3-methoxybenzoate, phenyl-2-hydroxybenzoate, phenyl -2-hydroxy-3-methylbenzoate, phenyl-2-hydroxy-4methylbenzoate, phenyl-2-hydroxy-5-methylbenzoate, phenyl 2-hydroxy-3-methoxybenzoate, 2,4-di-tert-butylphenyl-3,5-di-tert-butyl-4-hydroxybenzoate (trade name "TINUVIN120", manufactured by BASF); and the like.

Examples of the cyanoacrylate-based ultraviolet absorber (cyanoacrylate-based compound) include alkyl-2-cyanoacrylate, cycloalkyl-2-cyanoacrylate, alkoxyalkyl-2-cyanoacrylate, Alkenyl-2-cyanoacrylate, alkynyl-2-cyanoacrylate, etc. are mentioned.

The said ultraviolet absorber may be used independently, and may mix and use 2 or more types.

The absorption spectrum maximum absorption wavelength of the ultraviolet absorber preferably exists in a wavelength range of 200 to 400 nm, more preferably in a wavelength range of 240 to 380 nm. As such an ultraviolet absorber, a brand name "Tinuvin384-2" (maximum absorption wavelength 345 nm, BASF Corporation make) etc. are mentioned, for example.

The ultraviolet transmittance TUV ₁ of the first pressure sensitive adhesive layer for ultraviolet rays having a wavelength of 248 nm varies depending on the thickness of the first pressure sensitive adhesive layer, but is 75% or less (more preferably 70% or less, still more preferably 50% or less, the lower limit is It is preferably 5%). In addition, the ultraviolet transmittance, for example, the transmittance obtained by perpendicularly incident ultraviolet rays having a wavelength of 248 nm into the first pressure-sensitive adhesive layer using a spectrophotometer (product name "U-4100"), manufactured by Hitachi High-Tech Science Co., Ltd. can be measured

In addition, the value obtained by dividing the ultraviolet transmittance TUV ₁ of the first pressure sensitive adhesive layer of ultraviolet rays having a wavelength of 248 nm by the thickness t ₁ of the first pressure sensitive adhesive layer (TUV ₁ /t ₁ ) is preferably 5.00 or less, more preferably It is 4.90 or less, more preferably 4.80 or less, and the lower limit is preferably 0.50, more preferably 0.70, still more preferably 1.00.

The content of the ultraviolet absorber in the pressure-sensitive adhesive composition constituting the first pressure-sensitive adhesive layer varies depending on the thickness of the first pressure-sensitive adhesive layer. For example, when it is set to 15 μm, it is 0.05 to 0.05 to 100 parts by weight of the pressure-sensitive adhesive. 1.5 parts by weight is preferred, more preferably 0.07 to 1.2 parts by weight, still more preferably 1.0 to 1.0 parts by weight.

The pressure-sensitive adhesive composition constituting the first pressure-sensitive adhesive layer may contain an antioxidant. By including an antioxidant, deterioration such as discoloration during storage of the double-sided pressure-sensitive adhesive sheet for transfer of the present invention can be suppressed, and workability can be improved, such as making the double-sided pressure-sensitive adhesive transfer sheet easy to cut.

Examples of the antioxidant include phenol-based, phosphorus-based, sulfur-based, and amine-based antioxidants, and at least one selected from these is used. Among these, phenolic antioxidants are preferable, and hindered phenolic antioxidants are particularly preferable.

Specific examples of the phenolic antioxidant include 2,6-di-t-butyl-p-cresol, 2,6-di-t-butyl-4-ethylphenol, and 2,6-dicyclohexyl- as monocyclic phenolic compounds. 4-methylphenol, 2,6-diisopropyl-4-ethylphenol, 2,6-di-t-amyl-4-methylphenol, 2,6-di-t-octyl-4-n-propylphenol, 2,6-dicyclohexyl-4-n-octylphenol, 2-isopropyl-4-methyl-6-t-butylphenol, 2-t-butyl-4-ethyl-6-t-octylphenol, 2- Isobutyl-4-ethyl-6-t-hexylphenol, 2-cyclohexyl-4-n-butyl-6-isopropylphenol, styrenated mixed cresol, DL-α-tocopherol, stearyl β-(3,5 -Di-t-butyl-4-hydroxyphenyl)propionate or the like as a bicyclic phenolic compound, 2,2'-methylenebis(4-methyl-6-t-butylphenol), 4,4'- Butylidenebis(3-methyl-6-t-butylphenol), 4,4'-thiobis(3-methyl-6-t-butylphenol), 2,2'-thiobis(4-methyl-6 -t-butylphenol), 4,4'-methylenebis(2,6-di-t-butylphenol), 2,2'-methylenebis[6-(1-methylcyclohexyl)-p-cresol], 2,2'-ethylidenebis(4,6-di-t-butylphenol), 2,2'-butylidenebis(2-t-butyl-4-methylphenol), 3,6-dioxaocta Methylenebis[3-(3-t-butyl-4-hydroxy-5-methylphenyl)propionate], triethyleneglycolbis[3-(3-t-butyl-5-methyl-4-hydroxyphenyl) propionate], 1,6-hexanediolbis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], 2,2'-thiodiethylenebis[3-( 3,5-di-t-butyl-4-hydroxyphenyl)propionate] etc. as a tricyclic phenolic compound, 1,1,3-tris(2-methyl-4-hydroxy-5-t- Butylphenyl) butane, 1,3,5-tris (2,6-dimethyl-3-hydroxy-4-t-butylbenzyl) isocyanurate, 1,3,5-tris [(3,5-di -t-butyl-4-hydroxyphenyl) propionyloxyethyl] isocyanurate, tris (4-t-butyl-2,6-dimethyl-3-hydroxybenzyl) isocyanurate, 1,3, 5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene and the like as tetrakis[methylene-3-(3,5- di-t-butyl-4-hydroxyphenyl) propionate] methane, etc. as a phosphorus-containing phenolic compound, bis(3,5-di-t-butyl-4-hydroxybenzylphosphonate ethyl) calcium, bis (3,5-di-t-butyl-4-hydroxybenzylphosphonic acid ethyl) nickel etc. are mentioned.

These antioxidants may be used alone or in combination of two or more. The content of the deterioration inhibitor contained in the pressure-sensitive adhesive composition is, for example, 0.01 to 10 parts by weight with respect to 100 parts by weight of the first pressure-sensitive adhesive composition, from the viewpoint of suppressing deterioration such as discoloration during storage and workability of the double-sided pressure-sensitive adhesive sheet for transfer. It is preferable, 0.03 to 5 parts by weight is more preferable, and 0.1 to 3 parts by weight is still more preferable.

The pressure-sensitive adhesive composition constituting the first pressure-sensitive adhesive layer may contain any appropriate other components within a range that does not impair the effects of the present invention. Examples of such other components include tackifiers, inorganic fillers, organic fillers, metal powders, pigments, thin materials, softeners, plasticizers, conductive agents, surface lubricants, leveling agents, heat-resistant stabilizers, polymerization inhibitors, lubricants, and solvents. etc. can be mentioned.

<Second pressure-sensitive adhesive layer>

In the double-sided pressure-sensitive adhesive sheet for transfer according to the present invention, the second pressure-sensitive adhesive layer is a pressure-sensitive adhesive layer for temporarily fixing to the carrier substrate, and is composed of a peelable pressure-sensitive adhesive layer. The configuration that the second pressure-sensitive adhesive layer is composed of a peelable pressure-sensitive adhesive layer is preferable in that the second pressure-sensitive adhesive layer can be peeled from the carrier substrate without contamination of adhesive residues and the like, and the reworkability can be improved. do.

The second pressure-sensitive adhesive layer can be made into a peelable pressure-sensitive adhesive layer by adjusting the adhesiveness by the type, composition, degree of crosslinking, etc. of the pressure-sensitive adhesive, or by reducing the adhesive force by physical stimulation such as heat or electromagnetic waves such as ultraviolet rays.

The 180° peeling adhesive strength of the second pressure-sensitive adhesive layer to the glass plate at 25° C. is not particularly limited, but can be peeled from the carrier substrate without contamination of adhesive residue or the like, and from the viewpoint of improving the reworkability, 5000 mN/ It is preferably 25 mm or less, more preferably 3000 mN/25 mm or less, still more preferably 1000 mN/25 mm or less. Further, from the viewpoint of the adhesiveness of the carrier substrate to the second pressure sensitive adhesive layer, the 180° peel adhesive strength of the second pressure sensitive adhesive layer to the glass plate at 25°C is preferably 1 mN/25 mm or more, more preferably 5 mN/25 mm or more. am.

The 180° peel adhesive strength of the second pressure sensitive adhesive layer to the glass plate at 25 ° C. The ratio (P2b/P2a) of the 180° peel adhesive force at 25° C. to the glass plate of the second pressure-sensitive adhesive layer (hereinafter sometimes referred to as “P2b” in the present specification) is not particularly limited, but is 3 or less is preferable, and 2.5 or less is more preferable. In the configuration that P2b/P2a is 3 or less, the adhesive strength of the second pressure-sensitive adhesive layer to the carrier substrate does not increase when the electronic component received by the double-sided pressure-sensitive adhesive sheet for transfer of the present invention is transferred and mounted on the mounting substrate by thermal compression bonding. It is preferable in terms of good peeling and excellent reworkability.

The 180° peel adhesive strength at 25°C of the second pressure-sensitive adhesive layer can be measured in the same way as for the first pressure-sensitive adhesive layer.

The adhesive strength of the second pressure-sensitive adhesive layer can be adjusted by adjusting the type, composition, degree of crosslinking, etc. of the constituting pressure-sensitive adhesive, or by forming a weak boundary layer (WBL) by blending a light release agent or plasticizer.

In the double-sided pressure-sensitive adhesive sheet for transfer of the present invention, the thickness of the second pressure-sensitive adhesive layer is not particularly limited, but is preferably 1 μm or more, and more preferably 3 μm or more. When the thickness is more than a certain level, the second pressure-sensitive adhesive layer becomes easy to stably fix to the carrier substrate, which is preferable. The upper limit of the thickness of the second pressure-sensitive adhesive layer is not particularly limited, but is preferably 30 μm, and more preferably 20 μm. If the thickness is below a certain level, the second pressure-sensitive adhesive layer can be easily peeled off from the carrier substrate, and the reworkability is improved, which is preferable.

In the double-sided pressure-sensitive adhesive sheet for transfer of the present invention, the haze (according to JIS K7136) of the second pressure-sensitive adhesive layer is not particularly limited, but is preferably 10% or less, and more preferably 5% or less. If the haze is 10% or less, excellent transparency is obtained. For example, when the double-sided pressure-sensitive adhesive sheet for transfer is affixed to the carrier substrate, the pattern attached on the carrier substrate (eg, marker indicating the receiving position of the electronic part) can be visually recognized, which is preferable. In addition, the haze is obtained by, for example, forming a second pressure-sensitive adhesive layer on the separator and leaving it still in the state (23 ° C., 50% RH) for at least 24 hours, then peeling the separator, sliding glass (for example, total light transmittance What was bonded to 91.8% and haze 0.4%) can be used as a sample, and can be measured using a haze meter (product name "HM-150", manufactured by Murakami Shikisai Kijutsu Genkyujo).

In the double-sided pressure-sensitive adhesive sheet for transfer of the present invention, the total light transmittance (according to JIS K7361-1) of the second pressure-sensitive adhesive layer in the visible light wavelength region is not particularly limited, but is preferably 85% or more, and more preferably It is 88% or more. When the total light transmittance is 85% or more, excellent transparency is obtained. For example, when the double-sided pressure-sensitive adhesive sheet for transfer is affixed to the carrier substrate, the pattern attached on the carrier substrate (for example, a marker indicating the receiving position of the electronic part) can be visually recognized, which is preferable. In addition, the above-mentioned total light transmittance is measured by, for example, forming a second pressure-sensitive adhesive layer on a separator and leaving it still in a state (23° C., 50% RH) for at least 24 hours, then peeling the separator and sliding glass (for example, What was bonded to the thing of transmittance|permeability 91.8% and haze 0.4%) can be used as a sample, and it can measure using a haze meter (product name "HM-150", Murakami Shikisai Kijutsu Genkyujo product).

The pressure-sensitive adhesive constituting the second pressure-sensitive adhesive layer is not particularly limited, but examples thereof include silicone-based pressure-sensitive adhesives, urethane-based pressure-sensitive adhesives, acrylic pressure-sensitive adhesives, rubber-based pressure-sensitive adhesives, polyester-based pressure-sensitive adhesives, and polyamide-based pressure-sensitive adhesives used in the first pressure-sensitive adhesive layer above. , epoxy-based adhesives, vinylalkyl ether-based adhesives, fluorine-based adhesives, and the like. Among these, it can be peeled off from the carrier substrate without contamination of adhesive residues, etc., and from the viewpoint of improving reworkability, silicone-based adhesives, urethane-based adhesives, and acrylic-based adhesives are preferable, and urethane-based adhesives and acrylic-based adhesives are more preferable, and acrylic adhesives An adhesive is more preferred.

The second pressure-sensitive adhesive layer in the double-sided pressure-sensitive adhesive sheet for transfer of the present invention is a pressure-sensitive adhesive layer capable of intentionally reducing the adhesive force by an external action in the process of using the double-sided pressure-sensitive adhesive sheet for transfer (a pressure-sensitive adhesive layer capable of reducing the adhesive force) ), or may be a pressure-sensitive adhesive layer (adhesive force non-reducing type pressure-sensitive adhesive layer) in which the adhesive force is hardly or not reduced depending on the action from the outside during the use process of the double-sided pressure-sensitive adhesive sheet for transfer. It can be appropriately selected according to the method or condition of transferring the electronic component using

When the second pressure-sensitive adhesive layer is a pressure-sensitive adhesive layer capable of reducing adhesive strength, the second pressure-sensitive adhesive layer exhibits a relatively high adhesive strength and a relatively low adhesive strength in the manufacturing process or use process of the double-sided pressure-sensitive adhesive sheet for transfer according to the present invention. It becomes possible to distinguish and use the state. For example, in the process of using the double-sided pressure-sensitive adhesive sheet for transfer according to the present invention, in the step of receiving the electronic component by the first pressure-sensitive adhesive layer, the second pressure-sensitive adhesive layer exhibits relatively high adhesive strength, so that the transfer from the carrier substrate is used. It becomes possible to suppress/prevent the lifting of the used double-sided adhesive sheet. On the other hand, in the process of peeling the double-sided pressure-sensitive adhesive sheet for transfer according to the present invention from the carrier substrate, the reworkability can be improved by reducing the adhesive force of the second pressure-sensitive adhesive layer.

Examples of the pressure-sensitive adhesive forming the pressure-sensitive adhesive layer capable of reducing adhesive force include radiation-curable pressure-sensitive adhesives and heat-foaming pressure-sensitive adhesives. The adhesive which forms the adhesive force reduction possibility type adhesive layer can be used individually or in combination of 2 or more types.

As the radiation-curable pressure-sensitive adhesive, for example, a type of pressure-sensitive adhesive that can be cured by irradiation with electron beams, ultraviolet rays, α-rays, β-rays, γ-rays, or X-rays can be used. adhesive) can be used particularly preferably.

Examples of the radiation-curable pressure-sensitive adhesive include additive-type radiation-curable pressure-sensitive adhesives containing a base polymer such as an acrylic polymer and a radiation-polymerizable monomer component or oligomer component having a functional group such as a radiation-polymerizable carbon-carbon double bond. .

As the base polymer, an acrylic polymer similar to that of the first pressure sensitive adhesive layer can be used. In all monomer components for forming the acrylic polymer, from the point where the basic properties such as adhesiveness by hydrocarbon group-containing (meth)acrylic acid ester are appropriately expressed in the second adhesive layer and the adhesiveness and peelability are easily controlled , The ratio of the hydrocarbon group-containing (meth)acrylic acid ester is preferably 40% by weight or more, more preferably 60% by weight or more.

The acrylic polymer may also contain a hydroxy group-containing monomer. When the acrylic polymer in the second pressure sensitive adhesive layer contains a hydroxyl group-containing monomer, appropriate cohesive force is easily obtained in the second pressure sensitive adhesive layer. From the viewpoint of realizing appropriate adhesiveness and cohesion in the second pressure-sensitive adhesive layer, the ratio of the hydroxy group-containing monomer in the acrylic polymer is, for example, 0.1 to 30% by weight, preferably 0.5 to 20% by weight. .

The acrylic polymer may also contain a carboxy group-containing monomer. When the acrylic polymer in the second pressure sensitive adhesive layer contains a carboxyl group-containing monomer, suitable adhesion reliability is easily obtained in the second pressure sensitive adhesive layer. From the viewpoint of realizing appropriate adhesion reliability in the second pressure-sensitive adhesive layer, the ratio of the carboxyl group-containing monomer in the acrylic polymer is, for example, 0.1 to 30% by weight, preferably 0.5 to 20% by weight.

The acrylic polymer may also contain a vinyl ester monomer. When the acrylic polymer in the second pressure sensitive adhesive layer contains a vinyl ester monomer, appropriate cohesive force is easily obtained in the second pressure sensitive adhesive layer. From the viewpoint of realizing appropriate cohesive force in the second pressure-sensitive adhesive layer, the ratio of the vinyl ester-based monomer in the acrylic polymer is, for example, 0.1 to 60% by weight, preferably 0.5 to 50% by weight.

The acrylic pressure-sensitive adhesive composition forming the second pressure-sensitive adhesive layer may contain a crosslinking agent. For example, the low-molecular-weight substance in the second pressure-sensitive adhesive layer can be further reduced by crosslinking the acrylic polymer. In addition, the weight average molecular weight of the acrylic polymer can be raised to control the low tackiness and peelability. Examples of the crosslinking agent include polyisocyanate compounds, epoxy compounds, polyol compounds (polyphenolic compounds, etc.), aziridine compounds, melamine compounds, etc., and an isocyanate crosslinking agent and/or an epoxy crosslinking agent are preferred. In this case, the amount used is preferably about 10 parts by weight or less, more preferably 0.1 to 10 parts by weight, based on 100 parts by weight of the acrylic polymer.

A crosslinking accelerator may be used for the acrylic pressure-sensitive adhesive composition forming the second pressure-sensitive adhesive layer. The type of crosslinking accelerator can be appropriately selected according to the type of crosslinking agent to be used. In addition, in this specification, a crosslinking accelerator refers to a catalyst that increases the speed of a crosslinking reaction by a crosslinking agent. Examples of such a crosslinking accelerator include tin (Sn) such as dioctyltin dilaurate, dibutyltin dilaurate, dibutyltin diacetate, dibutyltin diacetylacetonate, tetra-n-butyltin, and trimethyltin hydroxide. ) containing compounds; amines such as N,N,N',N'-tetramethylhexanediamine and triethylamine, and N-containing compounds such as imidazoles; etc. are exemplified. Among them, Sn-containing compounds are preferred. The use of these crosslinking accelerators is particularly effective when a hydroxyl group-containing monomer is used as the parent monomer and an isocyanate-based crosslinking agent is used as the crosslinking agent. The amount of the crosslinking promoter included in the pressure-sensitive adhesive composition may be, for example, about 0.001 to 0.5 parts by weight (preferably about 0.001 to 0.1 parts by weight) based on 100 parts by weight of the acrylic polymer.

Examples of the radiation polymerizable monomer component include urethane (meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipenta Erythritol monohydroxy penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, 1,4-butanedioldi(meth)acrylate, etc. are mentioned. Examples of the radiation-polymerizable oligomer component include various oligomers such as urethane-based, polyether-based, polyester-based, polycarbonate-based, and polybutadiene-based oligomers, and those having a molecular weight of about 100 to 30,000 are preferable. The content of the radiation-curable monomer component and oligomer component in the radiation-curable pressure-sensitive adhesive forming the second pressure-sensitive adhesive layer is, for example, 5 to 500 parts by weight, preferably 40 to 150 parts by weight, based on 100 parts by weight of the base polymer. is about In addition, as an addition-type radiation curable adhesive, you may use what was disclosed by Unexamined-Japanese-Patent No. 60-196956, for example.

Examples of the radiation-curable pressure-sensitive adhesive include an intrinsic radiation-curable pressure-sensitive adhesive containing a base polymer having a radiation-polymerizable functional group such as a carbon-carbon double bond at the polymer side chain or at the polymer main chain terminal in the polymer main chain. The use of such an intrinsic radiation-curable pressure-sensitive adhesive tends to suppress unintended changes with time in adhesive properties due to migration of low-molecular-weight components in the formed second pressure-sensitive adhesive layer.

As the base polymer contained in the internal type radiation curable pressure-sensitive adhesive, an acrylic polymer is preferable. As a method for introducing a radiation polymerizable carbon-carbon double bond into an acrylic polymer, for example, a raw material monomer containing a monomer component having a first functional group is polymerized (copolymerized) to obtain an acrylic polymer, and then reacted with the first functional group. A method of condensation or addition reaction of a compound having a second functional group and a radiation polymerizable carbon-carbon double bond to an acrylic polymer while maintaining radiation polymerizability of the carbon-carbon double bond is exemplified.

Examples of the combination of the first functional group and the second functional group include a carboxy group and an epoxy group, an epoxy group and a carboxy group, a carboxy group and an aziridyl group, an aziridyl group and a carboxy group, a hydroxy group and an isocyanate group, an isocyanate group and a hydroxy group, and the like. Among these, a combination of a hydroxyl group and an isocyanate group and a combination of an isocyanate group and a hydroxyl group are preferable from the viewpoint of easiness of reaction tracking. Among them, it is technically difficult to produce a polymer having a highly reactive isocyanate group, and on the other hand, from the viewpoint of the ease of production and availability of an acrylic polymer having a hydroxy group, the first functional group is a hydroxy group and the second functional group is an isocyanate Combinations of genes are preferred. Examples of the isocyanate compound having an isocyanate group and a radiopolymerizable carbon-carbon double bond, ie, a radiation polymerizable unsaturated functional group-containing isocyanate compound, include methacryloyl isocyanate, 2-methacryloyloxyethyl isocyanate, and m-isopropyl isocyanate. Phenyl- (alpha), (alpha)- dimethylbenzyl isocyanate etc. are mentioned. In addition, as the acrylic polymer having a hydroxy group, a structural unit derived from the above-mentioned hydroxyl group-containing monomer or an ether compound such as 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, or diethylene glycol monovinyl ether is included. can be heard doing

It is preferable that the said radiation-curable adhesive contains a photoinitiator. Examples of the photopolymerization initiator include α-ketol compounds, acetophenone compounds, benzoin ether compounds, ketal compounds, aromatic sulfonyl chloride compounds, photoactive oxime compounds, benzophenone compounds, and thiochic acid. tonic compounds, camphorquinones, halogenated ketones, acylphosphine oxides, acylphosphonates, and the like. As said α-ketol compound, for example, 4-(2-hydroxyethoxy)phenyl(2-hydroxy-2-propyl)ketone, α-hydroxy-α,α'-dimethylacetophenone, 2- Methyl-2-hydroxypropiophenone, 1-hydroxycyclohexylphenyl ketone, etc. are mentioned. As said acetophenone type compound, for example, methoxy acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy acetophenone, 2-methyl-1-[4-(methylthio) -Phenyl]-2-morpholinopropane-1 etc. are mentioned. As said benzoin ether type compound, benzoin ethyl ether, benzoin isopropyl ether, anisoin methyl ether etc. are mentioned, for example. As said ketal type compound, benzyl dimethyl ketal etc. are mentioned, for example. As said aromatic sulfonyl chloride type compound, 2-naphthalene sulfonyl chloride etc. are mentioned, for example. Examples of the photoactive oxime-based compound include 1-phenyl-1,2-propanedione-2-(O-ethoxycarbonyl)oxime and the like. As said benzophenone type compound, benzophenone, benzoyl benzoic acid, 3,3'- dimethyl- 4-methoxy benzophenone etc. are mentioned, for example. As said thioxanthone compound, for example, thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, 2,4-dichlorothio Oxanthone, 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, etc. are mentioned. The content of the photopolymerization initiator in the radiation-curable pressure-sensitive adhesive is, for example, 0.05 to 20 parts by weight with respect to 100 parts by weight of the base polymer.

The heat-expandable pressure-sensitive adhesive is a pressure-sensitive adhesive containing a component (foaming agent, heat-expandable microsphere, etc.) that expands or expands when heated. As said foaming agent, various inorganic type foaming agents and organic type foaming agents are mentioned. Examples of the inorganic foaming agent include ammonium carbonate, ammonium hydrogen carbonate, sodium hydrogen carbonate, ammonium nitrite, sodium borohydride, and azides. Examples of the organic foaming agent include hydrofluoric alkanes such as trichloromonofluoromethane and dichloromonofluoromethane; azo compounds such as azobisisobutyronitrile, azodicarbonamide, and barium azodicarboxylate; hydrazine compounds such as p-toluenesulfonylhydrazide, diphenylsulfone-3,3'-disulfonylhydrazide, 4,4'-oxybis(benzenesulfonylhydrazide), and allylbis(sulfonylhydrazide); semicarbazide compounds such as p-toluylenesulfonylsemicarbazide and 4,4'-oxybis(benzenesulfonylsemicarbazide); triazole-based compounds such as 5-morpholyl-1,2,3,4-thiatriazole; and N-nitroso-based compounds such as N,N'-dinitrosopentamethylenetetramine and N,N'-dimethyl-N,N'-dinitroso terephthalamide. Examples of the heat-expandable microspheres include microspheres having a configuration in which a substance that is easily gasified and expands by heating is sealed in a shell, for example. Examples of substances that easily gasify and expand by heating include isobutane, propane, and pentane. Thermally expandable microspheres can be produced by enclosing a substance that easily gasifies and expands when heated in a shell-forming substance by a coacervation method or an interfacial polymerization method. As the shell-forming material, a material exhibiting thermal melting properties or a material capable of being ruptured by the thermal expansion action of the encapsulating material may be used. Examples of such substances include vinylidene chloride/acrylonitrile copolymer, polyvinyl alcohol, polyvinyl butyral, polymethyl methacrylate, polyacrylonitrile, polyvinylidene chloride, and polysulfone.

As said adhesive force non-reducing type adhesive layer, a pressure-sensitive adhesive layer is mentioned, for example. In addition, the pressure-sensitive adhesive layer includes a pressure-sensitive adhesive layer having a constant adhesive force while previously curing the pressure-sensitive adhesive layer formed of the radiation-curable pressure-sensitive adhesive described above with respect to the pressure-sensitive adhesive layer by irradiation with radiation. The pressure-sensitive adhesive forming the adhesive force non-reducing type pressure-sensitive adhesive layer can be used alone or in combination of two or more. Further, the entirety of the second pressure-sensitive adhesive layer may be a non-adhesive pressure-sensitive adhesive layer, or a part thereof may be a non-adhesive pressure-sensitive adhesive layer. For example, when the second pressure-sensitive adhesive layer has a single-layer structure, the entire second pressure-sensitive adhesive layer may be a non-adhesive pressure-sensitive adhesive layer, a specific portion of the second pressure-sensitive adhesive layer is a non-adhesive pressure-sensitive adhesive layer, and other The site may be an adhesive layer capable of reducing adhesive force. Further, when the second pressure-sensitive adhesive layer has a laminated structure, all the pressure-sensitive adhesive layers in the laminated structure may be adhesive non-reducing type pressure-sensitive adhesive layers, or some of the pressure-sensitive adhesive layers in the laminated structure may be adhesive non-reduced type pressure-sensitive adhesive layers.

Even if the pressure-sensitive adhesive layer (radiation-curable pressure-sensitive adhesive layer that has been irradiated) has a reduced adhesive force by irradiation, Adhesion due to the contained polymer component is exhibited, and it is possible to exhibit the minimum necessary adhesive force for the double-sided pressure-sensitive adhesive sheet for transfer of the present invention. In the case of using an irradiated radiation-curable pressure-sensitive adhesive layer, the entire second pressure-sensitive adhesive layer may be an irradiated radiation-curable pressure-sensitive adhesive layer, or a part of the second pressure-sensitive adhesive layer is irradiated with radiation in the direction of surface expansion of the second pressure-sensitive adhesive layer. It is a radiation curable pressure-sensitive adhesive layer, and the other portion may be a radiation-curable pressure-sensitive adhesive layer not irradiated with radiation. In the present specification, "radiation curable pressure-sensitive adhesive layer" refers to a pressure-sensitive adhesive layer formed of a radiation-curable pressure-sensitive adhesive, and a radiation-curable pressure-sensitive adhesive layer having radiation curability and radiation curing after the pressure-sensitive adhesive layer is cured by irradiation with radiation. Both sides of the finished radiation curable pressure-sensitive adhesive layer are included.

As the pressure-sensitive adhesive forming the pressure-sensitive adhesive layer, a known or common pressure-sensitive adhesive can be used, and an acrylic pressure-sensitive adhesive having an acrylic polymer as a base polymer can be preferably used. When the second pressure-sensitive adhesive layer contains an acrylic polymer as a pressure-sensitive adhesive, the acrylic polymer is preferably a polymer containing the largest number of structural units derived from (meth)acrylic acid ester in terms of weight ratio. As the acrylic polymer, for example, an acrylic polymer described as an acrylic polymer that can be included in the above-mentioned additive-type radiation curable pressure-sensitive adhesive can be employed.

<Description>

The substrate in the double-sided pressure-sensitive adhesive sheet for transfer according to the present invention is an element that functions as a support in the first pressure-sensitive adhesive layer or the second pressure-sensitive adhesive layer. As a base material, a plastic base material (especially a plastic film) is mentioned, for example. The substrate may be a single layer or may be a laminate of the same or different types of substrates.

Examples of the resin constituting the plastic substrate include low-density polyethylene, linear low-density polyethylene, medium-density polyethylene, high-density polyethylene, ultra-low-density polyethylene, random copolymerized polypropylene, block copolymerized polypropylene, homopolyprolene, polybutene, and polypropylene. Methylpentene, ethylene-vinyl acetate copolymer (EVA), ionomer, ethylene-(meth)acrylic acid copolymer, ethylene-(meth)acrylic acid ester (random, alternating) copolymer, ethylene-butene copolymer, ethylene-hexene copolymer polyolefin resins such as polymers; Polyurethane; polyesters such as polyethylene terephthalate (PET), polyethylene naphthalate, and polybutylene terephthalate (PBT); polycarbonate; polyimide; polyether ether ketone; polyetherimide; polyamides such as aramid and wholly aromatic polyamide; polyphenylsulfide; fluororesins; polyvinyl chloride; polyvinylidene chloride; cellulose resin; A silicone resin etc. are mentioned. The double-sided pressure-sensitive adhesive sheet for transfer of the present invention exhibits good heat resistance that hardly causes expansion or contraction due to heat when the received electronic component is thermally compressed (for example, 150 ° C.) on a mounting substrate and transferred and mounted, and is mounted with high precision. From the viewpoint of being able to do this, the base material contains a heat-resistant resin such as polyimide (PI), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyamide (PA), and polyether ether ketone (PEEK) as a main component. It is preferable to do so, and it is more preferable to include polyimide as a main component. In addition, the main component of a base material is a component which occupies the largest weight ratio among constituent components. The said resin can be used individually or in combination of 2 or more types. When the second pressure-sensitive adhesive layer is a radiation-curable pressure-sensitive adhesive layer as described above, the base material preferably has radiation transparency.

When the base material is a plastic film, the plastic film may be non-oriented or oriented in at least one direction (uniaxial direction, biaxial direction, etc.), but non-orientation is preferable in view of less heat shrinkability.

The surface on the side of the first pressure-sensitive adhesive layer and/or the second pressure-sensitive adhesive layer of the base material is subjected to, for example, corona discharge treatment, plasma treatment, sand mat treatment, and ozone exposure treatment for the purpose of improving adhesion to the pressure-sensitive adhesive layer, retention, and the like. , flame exposure treatment, high-voltage electric shock exposure treatment, physical treatment such as ionizing radiation treatment; chemical treatment such as chromic acid treatment; coating agent (undercoat agent); Surface treatment such as adhesion facilitating treatment by silicone primer treatment may be performed. Further, in order to impart antistatic ability, a conductive polymer such as PEDOT-PSS may be coated in addition to providing a conductive vapor deposition layer containing metals, alloys, oxides thereof, and the like on the surface of the substrate. It is preferable that the surface treatment for improving adhesion is performed on the entire surface of the adhesive layer side in the base material.

The thickness of the substrate is preferably 5 μm or more, more preferably 10 μm or more, still more preferably 15 μm or more, from the viewpoint of securing strength for the substrate to function as a support in the double-sided pressure-sensitive adhesive sheet for transfer according to the present invention. μm or more, particularly preferably 20 μm or more. Further, from the viewpoint of realizing appropriate flexibility in the double-sided pressure-sensitive adhesive sheet for transfer of the present invention, the thickness of the substrate is preferably 200 μm or less, more preferably 180 μm or less, still more preferably 150 μm or less.

In the double-sided pressure-sensitive adhesive sheet for transfer of the present invention, the haze (according to JIS K7136) of the substrate is not particularly limited, but is preferably 10% or less, and more preferably 5.0% or less. If the haze is 10% or less, excellent transparency is obtained. For example, when the double-sided pressure-sensitive adhesive sheet for transfer is affixed to the carrier substrate, the pattern attached on the carrier substrate (eg, marker indicating the receiving position of the electronic part) can be visually recognized, which is preferable. In addition, the said haze can be measured using a haze meter (product name "HM-150", Murakami Shikisai Kijutsu Genkyuso make).

In the double-sided pressure-sensitive adhesive sheet for transfer of the present invention, the total light transmittance (according to JIS K7361-1) of the substrate in the visible light wavelength region is not particularly limited, but is preferably 85% or more, more preferably 88% or more. am. If the total light transmittance is 85% or more, excellent transparency is obtained. For example, when the double-sided pressure-sensitive adhesive sheet for transfer is affixed to the carrier substrate, the pattern attached on the carrier substrate (e.g., a marker indicating the receiving position of the electronic part) ) can be visually recognized, which is preferable. In addition, the said total light transmittance can be measured using a haze meter (product name "HM-150", Murakami Shikisai Kijutsu Genkyujo make).

<Separator>

The surface of the pressure-sensitive adhesive layer (adhesive surface of the first pressure-sensitive adhesive layer and/or the second pressure-sensitive adhesive layer) of the double-sided pressure-sensitive adhesive sheet for transfer according to the present invention may be protected by a release liner (separator) until use. The separator is used as a protective material for the pressure-sensitive adhesive layer, and is peeled off when the pressure-sensitive adhesive sheet is applied to an adherend. 2 is a cross-sectional schematic diagram showing an embodiment of a double-sided pressure-sensitive adhesive transfer sheet according to the present invention, in which 1 is a double-sided pressure-sensitive adhesive sheet for transfer, 10 is a base material, 11 is a first pressure sensitive adhesive layer, 12 is a second pressure sensitive adhesive layer, and 110 is a double-sided pressure sensitive adhesive sheet for transfer. , 120 denotes a separator. In addition, a separator does not necessarily need to be provided.

As the separator, a conventional release paper or the like can be used. Specifically, for example, in addition to a substrate having a release treatment layer by a release treatment agent on at least one surface, a fluorine-based polymer (e.g., polytetrafluoroethylene) , polychlorotrifluoroethylene, polyvinyl fluoride, polyvinylidene fluoride, tetrafluoroethylene-hexafluoropropylene copolymer, chlorofluoroethylene-vinylidene fluoride copolymer, etc.) A low-adhesive base material made of a polymer (eg, olefin-based resin such as polyethylene or polypropylene) can be used.

As the separator, for example, a separator in which a release treatment layer is formed on at least one surface of a separator substrate can be suitably used. Examples of such separator substrates include polyester films (polyethylene terephthalate films, etc.), olefinic resin films (polyethylene films, polypropylene films, etc.), polyvinyl chloride films, polyimide films, polyamide films (nylon films), and rayon films. (2 to 3 complex of layers) and the like.

The exfoliation treatment agent constituting the exfoliation treatment layer is not particularly limited, and examples thereof include a silicone-based exfoliation treatment agent, a fluorine-based exfoliation treatment agent, and a long-chain alkyl-based exfoliation treatment agent. A peeling agent can be used individually or in combination of 2 or more types. Moreover, since the 1st adhesive layer is comprised by the low-adhesion adhesive layer, it is also possible to use the base material which has not been treated with the peeling agent as a separator.

In the separator, an antistatic layer may be formed on at least one surface of the substrate for the separator in order to prevent adverse effects on electronic components. The antistatic layer may be formed on one surface (exfoliation treated surface or untreated surface) of the separator, or may be formed on both surfaces (peeling treated surface and untreated surface) of the separator.

Examples of the antistatic agent contained in the antistatic resin include quaternary ammonium salts, pyridinium salts, cationic antistatic agents having cationic functional groups such as primary, secondary, and tertiary amino groups, sulfonic acid salts, sulfate ester salts, and phosphophones. Anionic antistatic agents having anionic functional groups such as acid salts and phosphate ester salts, amphoteric antistatic agents such as alkylbetaine and its derivatives, imidazoline and its derivatives, alanine and its derivatives, amino alcohol and its derivatives, glycerin and its derivatives; derivatives, nonionic antistatic agents such as polyethylene glycol and derivatives thereof, and further ion conductive polymers obtained by polymerizing or copolymerizing the above cationic, anionic, or zwitterionic monomers having ionic conductive groups. These compounds may be used alone or in combination of two or more.

The thickness of the separator is not particularly limited, and may be appropriately selected in the range of 5 to 100 µm.

The method for producing the double-sided pressure-sensitive adhesive sheet for transfer according to the present invention varies depending on the composition of the pressure-sensitive adhesive composition, etc., and is not particularly limited, and a known formation method can be used. For example, the following (1) to (4), etc. method can be cited.

(1) coating (coating) the pressure-sensitive adhesive composition on a substrate to form a composition layer, and curing the composition layer (for example, curing by thermal curing or irradiation of active energy rays such as ultraviolet rays) to form an adhesive layer, How to make an adhesive sheet

(2) Forming a composition layer by applying (coating) the pressure-sensitive adhesive composition on a separator, and curing the composition layer (for example, curing by thermal curing or irradiation of active energy rays such as ultraviolet rays) to form an adhesive layer. and then transferring the corresponding pressure-sensitive adhesive layer onto a substrate to produce a pressure-sensitive adhesive sheet.

(3) A method of producing a pressure-sensitive adhesive sheet by applying (coating) the pressure-sensitive adhesive composition onto a substrate and drying the pressure-sensitive adhesive composition to form a pressure-sensitive adhesive layer.

(4) A method of manufacturing a pressure-sensitive adhesive sheet by applying (coating) the pressure-sensitive adhesive composition on a separator, drying the pressure-sensitive adhesive layer to form a pressure-sensitive adhesive layer, and then transferring the pressure-sensitive adhesive layer onto a substrate.

As the curing method in the above (1) to (4), a method of thermal curing is preferable from the viewpoint of being excellent in productivity and being capable of forming a homogeneous and smooth surface adhesive layer.

As a method of applying (coating) the pressure-sensitive adhesive composition on a predetermined surface, a known coating method can be employed, and is not particularly limited, but examples include roll coating, kiss roll coating, gravure coating, reverse coating, and roll coating. brush, spray coating, dip roll coating, bar coating, knife coating, air knife coating, curtain coating, lip coating, and extrusion coating methods using a die coater and the like.

The thickness (total thickness) of the double-sided pressure-sensitive adhesive sheet for transfer of the present invention is not particularly limited, but is preferably 10 μm or more, and more preferably 15 μm or more. If the thickness is more than a certain level, the first pressure-sensitive adhesive layer can easily receive the electronic component with high precision, which is preferable. The upper limit of the thickness (total thickness) of the double-sided pressure-sensitive adhesive sheet for transfer according to the present invention is not particularly limited, but is preferably 500 μm, and more preferably 300 μm. If the thickness is below a certain level, it is easy to transfer the electronic component to the mounting substrate with high precision, which is preferable. Note that the thickness of the separator is not included in the thickness of the double-sided pressure-sensitive adhesive sheet for transfer according to the present invention.

The haze (according to JIS K7136) of the double-sided pressure-sensitive adhesive sheet for transfer according to the present invention is not particularly limited, but is preferably 10% or less, and more preferably 5.0% or less. If the haze is 10% or less, excellent transparency is obtained. For example, when the double-sided pressure-sensitive adhesive sheet for transfer is affixed to the carrier substrate, the pattern attached on the carrier substrate (eg, marker indicating the receiving position of the electronic part) can be visually recognized, which is preferable. In addition, the haze is determined by leaving the double-sided adhesive sheet for transfer at least 24 hours (23° C., 50% RH) for at least 24 hours, then peeling off the separator, and removing the slide glass (e.g., total light transmittance). What was bonded to 91.8% and haze 0.4%) can be used as a sample, and can be measured using a haze meter (product name "HM-150", manufactured by Murakami Shikisai Kijutsu Genkyujo).

The total light transmittance (according to JIS K7361-1) in the visible light wavelength region of the double-sided pressure-sensitive adhesive sheet for transfer according to the present invention is not particularly limited, but is preferably 85% or more, and more preferably 88% or more. If the total light transmittance is 85% or more, excellent transparency is obtained. For example, when the double-sided pressure-sensitive adhesive sheet for transfer is affixed to the carrier substrate, the pattern attached on the carrier substrate (e.g., a marker indicating the receiving position of the electronic part) ) can be visually recognized, which is preferable. In addition, the above-mentioned total light transmittance is measured by, for example, leaving the double-sided pressure-sensitive adhesive sheet for transfer in a state (23° C., 50% RH) for at least 24 hours, then peeling off the separator, if it has one, and applying a slide glass (for example, What was bonded to the thing of transmittance|permeability 91.8% and haze 0.4%) can be used as a sample, and it can measure using a haze meter (product name "HM-150", Murakami Shikisai Kijutsu Genkyujo product).

The double-sided pressure-sensitive adhesive sheet for transfer of the present invention is suitably used for a method of mounting electronic parts on a mounting board. The method of mounting an electronic component on a mounting board using the double-sided pressure-sensitive adhesive sheet for transfer of the present invention preferably includes the following steps.

A step of receiving the diced electronic component into the first pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive sheet for transfer (first step)

A step of transferring the electronic component received by the first pressure-sensitive adhesive layer to a mounting substrate (second step)

Fig. 3 is a cross-sectional schematic diagram showing an embodiment of a first step in a method for mounting an electronic component on a mounting substrate using the double-sided pressure-sensitive adhesive sheet for transfer according to the present invention.

In (a) of FIG. 3 , the double-sided pressure-sensitive adhesive sheet 1 for transfer is bonded to the carrier substrate 22 on the adhesive side of the second pressure-sensitive adhesive layer 12 . The surface adhered to the second pressure sensitive adhesive layer 12 of the carrier substrate 22 may be provided with a marking pattern for arranging electronic components. Since the double-sided pressure-sensitive adhesive sheet 1 for transfer has high transparency, the marking pattern adhered to the carrier substrate 22 can be visually recognized.

On the top of the adhesive face of the first pressure sensitive adhesive layer 11 of the double-sided pressure sensitive adhesive sheet 1 for transfer, in a state where a plurality of electronic components 21 separated into pieces by dicing are adhered to the dicing tape 20, It faces the adhesive surface of the 1st adhesive layer 11, and is arrange|positioned apart.

In (b) of FIG. 3, the electronic component 21 is pierced and pressed with the pin member 23 from the surface on which the electronic component 21 of the dicing tape 20 is not adhered, and the electronic component 21 is removed. 1 The adhesive face of the 1st adhesive layer 11 is received by bringing it close to the adhesive face of the adhesive layer 11. Receiving may be performed by bringing the electronic component 21 into contact with the first pressure-sensitive adhesive layer 11, or may be performed in a non-contact manner. In the case of receiving in a non-contact manner, the electronic component 21 is pierced and pressed until the electronic component 21 peels off from the dicing tape 20, and the electronic component 21 is dropped onto the adhesive surface. In the case of contacting and receiving, the adhesive surface of the first pressure sensitive adhesive layer 11 has low adhesiveness and the stress applied when the electronic component 21 is received is weak, so damage to the electronic component 21 can be suppressed. In the case of receiving without contact, since the adhesive face of the first adhesive layer 11 is low-adhesive, the dropped electronic component 21 can be caught with high positioning accuracy. Alternatively, the electronic component 21 may be separated from the dicing tape 20 by irradiating radiation such as ultraviolet rays or laser beams instead of the fin member 23 .

Reception of the electronic component 21 to the first pressure-sensitive adhesive layer 11 may be performed individually, or a plurality of pieces may be collectively performed. 3(c) shows a state in which all electronic components 21 of the dicing tape 20 are received on the adhesive face of the first adhesive layer 11 of the double-sided adhesive sheet 1 for transfer. It is a cross-sectional schematic.

Fig. 4 is a cross-sectional schematic diagram showing a second step in a method for mounting electronic components using the double-sided pressure-sensitive adhesive sheet of the present invention on a mounting board.

As shown in FIG. 4(a), the first pressure sensitive adhesive layer of the double-sided pressure-sensitive adhesive sheet 1 for transfer ( 11), the arrayed electronic components 21 are placed on the adhesive surface. Next, as shown in FIG. 4(b), the circuit surface 31 of the mounting substrate 30 and the adhesive surface of the first adhesive layer 11 of the double-sided adhesive sheet 1 for transfer are arranged on the adhesive surface. The electronic component 21 is brought closer to bring the electronic component 21 into contact with the circuit surface 31 of the mounting board 30 .

The transfer of the electronic component 21 to the circuit surface 31 of the mounting board 30 may be performed by thermal compression bonding (for example, at 150° C. for 1 minute). Since the base material 10, the first pressure sensitive adhesive layer 11, and/or the second pressure sensitive adhesive layer 12 constituting the double-sided pressure sensitive adhesive sheet 1 for transfer have excellent heat resistance, they do not expand or contract by thermal compression bonding. , Since the adhesive force is difficult to change, it can be transferred to the circuit surface 31 of the mounting board 30 of the electronic component 21 with high precision.

Next, as shown in FIG. 4(c), the electronic component 21 is peeled from the first pressure sensitive adhesive layer 11 by separating the double-sided pressure sensitive adhesive sheet 1 for transfer and the mounting substrate 30, It is transferred to the circuit surface 31 of the mounting board 30 . Since the first adhesive layer 11 is composed of a low-adhesive adhesive layer, the electronic component 21 can be easily peeled off and the electronic component 21 can be efficiently mounted on the mounting board 30 without being damaged. there is.

After the electronic component 21 is mounted on the mounting board 30, the double-sided adhesive sheet 1 for transfer in FIG. 4(c) may be peeled off from the carrier board 22 (not shown). Since the second pressure sensitive adhesive layer 12 is composed of a peelable pressure sensitive adhesive layer, it can be peeled off without adhesive residue and has excellent reworkability, so that the carrier substrate 22 can be easily reused.

Although it does not specifically limit as an electronic component mounted on a mounting board, It can use suitably for a fine and thin semiconductor chip or LED chip.

Example

The present invention will be explained in more detail below by giving examples, but the present invention is not limited by these examples at all.

<Example 1>

Silicone adhesive (addition reaction type silicone adhesive, trade name "X-40-3306", manufactured by Shin-Etsu Chemical Industry Co., Ltd.) 100 parts by weight, platinum-based catalyst 1 (trade name "CAT-PL-50T", Shin-Etsu 1.4 parts by weight of Kagaku Kogyo Co., Ltd.), 5 parts by weight of silicone-based release agent 1 (addition reaction type silicone-based release agent containing dimethylpolysiloxane as a main component, trade name "KS-776A", manufactured by Shin-Etsu Chemical Industry Co., Ltd.) and 0.2 parts by weight of an ultraviolet absorber (trade name "Tinuvin384-2", maximum absorption wavelength 345 nm, manufactured by BASF), diluted with toluene so that the total solid content is 25% by weight, mixed with a disper, and silicone pressure-sensitive adhesive composition (1) was prepared.

Silicone-based pressure-sensitive adhesive composition (1) is dried on the silicone-primed surface of a base film (polyester film coated with silicone primer on one side, thickness: 75 μm, trade name “Diafoil MRF#75”, manufactured by Mitsubishi Jushi Co., Ltd.) It was applied so that the thickness of the paste after that would be 15 μm, and cured and dried under conditions of a drying temperature of 120° C. and a drying time of 5 minutes. In this way, a film having a silicone-based pressure-sensitive adhesive layer on the silicone primer-treated layer of the base film was obtained.

Further, on the adhesive side of the silicone-based adhesive film, a separator 1 (polyethylene terephthalate film, thickness 25 µm, trade name "Lumiror S10#25", manufactured by Toyobo Co., Ltd.) is bonded to the silicon-based adhesive film. The pressure-sensitive adhesive layer was protected, and a laminate 1 having a laminated structure of [separator (1) layer]/[silicone-based pressure-sensitive adhesive (1) layer]/[base film layer] was obtained.

Next, 100 parts by weight of 2-ethylhexyl acrylate (2EHA) (manufactured by Nippon Shokubai Co., Ltd.), 2-hydroxyethyl acryl 4 parts by weight of late (HEA) (manufactured by Toagosei Co., Ltd.), 0.02 part by weight of 2,2'-azobisisobutyronitrile (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a polymerization initiator, 180 parts by weight of ethyl acetate Part was introduced, nitrogen gas was introduced with gentle stirring, and polymerization was carried out for 6 hours while maintaining the liquid temperature in the flask at around 65 ° C., A solution of an acrylic copolymer having a weight average molecular weight of 560,000 (solid content: 35% by weight) was prepared. .

To the solution of the adjusted acrylic copolymer, 4.0 parts by weight of Coronate HX (manufactured by Tosoh Co., Ltd.) in terms of solid content as a crosslinking agent and Envirizer OL-1 (Tokyo Fine Chemical (Tokyo Fine Chemical) as a crosslinking catalyst) with respect to 100 parts by weight of the solid content. Note) agent) was added in 0.02 parts by weight in terms of solid content, diluted with toluene so that the total solid content was 25% by weight, and stirred with a disper. It is applied to the peeling treatment layer side of a thickness of 38 μm, trade name “MRF#38”, manufactured by Mitsubishi Chemical Co., Ltd. with a fountain roll so that the thickness after drying is 20 μm, and cured under conditions of a drying temperature of 130 ° C. and a drying time of 30 seconds. dried In this way, an acrylic pressure-sensitive adhesive layer was formed on the separator 2 .

Next, the base film side (non-silicone primer treated side) of the layered product 1 obtained above is bonded to the surface of the acrylic pressure-sensitive adhesive layer, [separator (1) layer] / [silicone-based pressure-sensitive adhesive (1) layer (first Pressure-sensitive adhesive layer)] / [base film layer] / [acrylic pressure-sensitive adhesive layer (second pressure-sensitive adhesive layer)] / [separator (2) layer] A double-sided pressure-sensitive adhesive sheet for transfer was obtained.

<Examples 2 to 6, Comparative Examples 1 and 2>

In the same manner as in Example 1, using a silicone-based pressure-sensitive adhesive composition in which an ultraviolet absorber (trade name "Tinuvin384-2, maximum absorption wavelength 345 nm, manufactured by BASF) was blended so as to have the compounding amount shown in Table 1, so that the thickness shown in Table 1 was first A pressure-sensitive adhesive layer was formed to obtain double-sided pressure-sensitive adhesive sheets for transfer, respectively.

<evaluation>

About the double-sided adhesive sheet for transcription|transfer obtained by the Example and the comparative example, the following measurement and evaluation were performed. The results are shown in Table 1.

(ultraviolet ray transmittance)

A thin slice was cut from the first pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive sheet for transfer using a microtome, and using a microtome, ultraviolet, visible, and near-infrared spectrophotometer (product name: "MSV-5200DGK", manufactured by Nippon Bunko), in the wavelength range of 200 to 800 nm. The transmittance was measured, and the value at a wavelength of 248 nm was defined as the ultraviolet transmittance TUV ₁ .

(excitation height)

The double-sided adhesive sheet for transfer from which the separator (1) layer was peeled off was irradiated with an ultraviolet laser (wavelength: 248 nm, laser beam spot cross-sectional area: 15300 μm ² , output: 100 mJ/cm 2 ) from the silicon-based adhesive layer side, pulse time: 10 nsec, frequency: 100 Hz, 1 It irradiated so that it might become 9 dots (average irradiation area 15300 micrometer ^<2> ) in mm<2>. For those 9 dots, a surface observation image obtained using a laser microscope (product name "VK-X100", manufactured by Keyence Corporation) was analyzed, and the lifting height _Rz2 after irradiation was taken as the average value of the maximum height for each dot. got it Moreover, about the double-sided adhesive sheet for transfer before irradiation with an ultraviolet laser, the lifting height _Rz1 before irradiation was similarly obtained from the surface observation image of the 9-dot equivalent location.

(excitation area)

An ultraviolet laser (wavelength: 248 nm, laser beam size: 130 × 105 μm (laser beam spot cross-sectional area: 13650 μm ² , output: 100 mJ/cm 2 ) was applied to the double-sided adhesive sheet for transfer from which the separator (1) layer was peeled off, from the side of the silicon-based adhesive layer. Pulse time of 10 nsec, frequency of 100 Hz, 9 dots (average irradiation area 15300 μm ² ) were irradiated in 1 mm 2 . For each dot of those 9 dots, a digital microscope (product name “VHX-700F”, Keyence Co., Ltd.) ) was used to take a surface observation image at an observation magnification of 200 times, analyze this with image processing software ImageJ, and find the area where lifting occurred (lifting area) as an average value of 9 dots. Silver was obtained as an area ratio of the lifting area to the laser irradiation area of 15300 μm ² .

(transfer precision)

The double-sided pressure-sensitive adhesive sheet for transfer from which the separator 1 is peeled is attached to a dicing ring so that the first pressure-sensitive adhesive layer is the surface, and diced to a depth of 10 μm on the surface of the double-sided pressure-sensitive adhesive sheet to obtain a plurality of 1 mm squares on one side. Markings were attached.

A semiconductor wafer that has been subjected to pretreatment with a laser beam so as to be cut to a size of 1 mm × 1 mm during expansion is polished to a thickness of 30 μm, and then bonded to a dicing die-bonding film to obtain a dicing die-bonding film with a semiconductor wafer got A dicing die-bonding film with a semiconductor wafer is held on a dicing ring of a die separator (product name "DDS2300", manufactured by Disco), and a cool expander unit expands the temperature at -15°C and expands at an expand speed of 200 mm/sec. Cool expand was performed under the conditions of an expand amount of 11 mm, the semiconductor wafer and the die bond layer were cut, and room temperature expand was performed under the conditions of an expand speed of 1 mm/sec and an expand amount of 7 mm at room temperature, and further, While maintaining the expanded state, the dicing tape at the outer periphery of the semiconductor chip is thermally shrunk under the conditions of a heat temperature of 200° C., an air volume of 40 L/min, a heat distance of 20 mm, and a rotation speed of 3°/sec to form a semiconductor wafer and A dicing die-bonding film having a semiconductor chip with a die-bonding layer in which the die-bonding layer was maintained in a split state was obtained.

A dicing die-bonding film with the surface having the semiconductor chip with the die-bonding layer facing downward, and a double-sided pressure-sensitive adhesive sheet for transfer having the marked first pressure-sensitive adhesive layer facing upward, while aligning the position of the semiconductor chip with the die-bonding layer and the marking. , Arranged so as to face each other with a clearance of 1 mm, pierced and pressed with a needle from the upper side (rear side) of the dicing die-bonding film, and accurately dropped 10 semiconductor chips with a die-bonding layer onto the adhesive surface of the first pressure-sensitive adhesive layer at the marking position, , to obtain a double-sided pressure-sensitive adhesive sheet for transfer from which the semiconductor chip was received.

With respect to the double-sided adhesive sheet for transfer to which the semiconductor chip was received, an ultraviolet laser (wavelength 248 nm, laser beam spot cross-section area 15300 μm ² , output 100 mJ/cm 2 , frequency 100 Hz, pulse width 10 ns) to form an alignment mark, and based on the alignment mark, a mounting substrate with a corresponding marking is installed and aligned, and a semiconductor chip having a die bond layer is transferred to the aligned mounting substrate, The semiconductor chip with the die bond layer was confirmed using a microscope, and the positioning accuracy was evaluated according to the following criteria.

○: A semiconductor chip with a die-bonding layer in which a misalignment occurred with respect to the marking position of the mounting substrate was not confirmed.

x: A semiconductor chip with a die-bonding layer was found to be displaced with respect to the marking position of the mounting substrate.

In all of the double-sided pressure-sensitive adhesive sheets for transfer of Examples 1 to 6 having the configuration of the present invention, displacement of the semiconductor chip due to ultraviolet laser irradiation was suppressed. On the other hand, in the double-sided pressure-sensitive adhesive sheets for transfer in Comparative Examples 1 and 2, in which the ratio (R _z1 /R _z2 ) deviated from the configuration of the present invention, displacement of the semiconductor chip occurred.

1: Double-sided adhesive sheet for transfer
10: registration
11: first pressure-sensitive adhesive layer
12: second pressure-sensitive adhesive layer
110, 120: separator
20: dicing tape
21: electronic components
22: carrier substrate
23: Pin member
30: mounting board
31: circuit plane

Claims (4)

A double-sided pressure-sensitive adhesive sheet for transfer in which a first pressure-sensitive adhesive layer, a base material, and a second pressure-sensitive adhesive layer are laminated in this order,
The first pressure-sensitive adhesive layer is made of a low-adhesive pressure-sensitive adhesive layer,
The second pressure-sensitive adhesive layer is composed of a peelable pressure-sensitive adhesive layer,
The ratio of the lifting height R _z1 before irradiation to the lifting height R _z2 after irradiating the first pressure-sensitive adhesive layer with an ultraviolet laser having a wavelength of 248 nm at a beam size of 130 × 105 μm, an output of 100 mJ / cm 2 , a pulse width of 10 ns, and a frequency of 100 Hz ( A double-sided pressure-sensitive adhesive sheet for transfer, wherein R _z1 /R _z2 ) is 0.2 to 1600. The method of claim 1, wherein the first pressure-sensitive adhesive layer is irradiated with an ultraviolet laser having a wavelength of 248 nm at a beam size of 130 × 105 μm, an output of 100 mJ / cm 2, a pulse width of 10 ns, and a frequency of 100 Hz, A double-sided pressure-sensitive adhesive sheet for transfer having an area ratio of 20.0% or less. A double-sided pressure-sensitive adhesive sheet for transfer in which a first pressure-sensitive adhesive layer, a base material, and a second pressure-sensitive adhesive layer are laminated in this order,
The first pressure-sensitive adhesive layer is made of a low-adhesive pressure-sensitive adhesive layer,
The second pressure-sensitive adhesive layer is composed of a peelable pressure-sensitive adhesive layer,
When the first pressure-sensitive adhesive layer is irradiated with an ultraviolet laser having a wavelength of 248 nm at a beam size of 130 × 105 μm, an output of 100 mJ / cm 2 , a pulse width of 10 ns, and a frequency of 100 Hz, the area ratio of the lifted area to the entire irradiated area is 20.0% or less. , Double-sided adhesive sheet for transfer. The method of claim 1 or 2, wherein the ratio (R _z2 /t ₁ ) of the lifting height R _z2 (μm) to the thickness t ₁ (μm) of the first pressure-sensitive adhesive layer is 1.0 or less, double-sided adhesion for transfer Sheet.

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