Search

EP-4737530-A1 - ACTIVE ENERGY RAY-CURABLE ADHESIVE COMPOSITION AND ADHESIVE SHEET

EP4737530A1EP 4737530 A1EP4737530 A1EP 4737530A1EP-4737530-A1

Abstract

An active energy ray-curable pressure-sensitive adhesive composition contains no a compound having two or more reactive unsaturated bonds in one molecule, and contains an acrylic pressure-sensitive adhering polymer (A) having at least one selected from the group consisting of an ether group, a hydroxyl group, aliphatic tertiary carbon, a secondary amino group and a tertiary amino group in a side chain. The acrylic pressure-sensitive adhering polymer (A) includes a structural unit (U1) having a hydrogen abstraction type photopolymerization initiator structure. A content rate of the structural unit (U1) in the acrylic pressure-sensitive adhering polymer (A) is 0.1% by mass or more and 50% by mass or less relative to the entire structural unit of the acrylic pressure-sensitive adhering polymer (A), and a content of a crosslinking agent is 0 parts by mass or more and 3 parts by mass or less based on a content of the acrylic pressure-sensitive adhering polymer (A) of 100 parts by mass.

Inventors

  • TAKEYA, NOBUYUKI
  • OOFUSA, Kazuki
  • HASHIMOTO, YUUSUKE

Assignees

  • Toagosei Co., Ltd.

Dates

Publication Date
20260506
Application Date
20240624

Claims (12)

  1. An active energy ray-curable pressure-sensitive adhesive composition, comprising no a compound comprising two or more reactive unsaturated bonds in one molecule, and comprising an acrylic pressure-sensitive adhering polymer (A) comprising at least one selected from the group consisting of an ether group, a hydroxyl group, aliphatic tertiary carbon, a secondary amino group and a tertiary amino group in a side chain, wherein the acrylic pressure-sensitive adhering polymer (A) comprises a structural unit (U1) comprising a hydrogen abstraction type photopolymerization initiator structure, a content rate of the structural unit (U1) in the acrylic pressure-sensitive adhering polymer (A) is 0.1% by mass or more and 50% by mass or less relative to the entire structural unit of the acrylic pressure-sensitive adhering polymer (A), and a content of a crosslinking agent is 0 parts by mass or more and 3 parts by mass or less based on a content of the acrylic pressure-sensitive adhering polymer (A) of 100 parts by mass.
  2. The active energy ray-curable pressure-sensitive adhesive composition according to claim 1, wherein the acrylic pressure-sensitive adhering polymer (A) comprises a structural unit (U2) derived from a (meth)acrylic monomer comprising at least one selected from the group consisting of an ether group, a hydroxyl group, aliphatic tertiary carbon (except for carbon atoms constituting a carbon-carbon double bond in a methacryloyl group), a secondary amino group and a tertiary amino group, and a content rate of the structural unit (U2) in the acrylic pressure-sensitive adhering polymer (A) is 10% by mass or more relative to the entire structural unit of the acrylic pressure-sensitive adhering polymer (A).
  3. The active energy ray-curable pressure-sensitive adhesive composition according to claim 1, wherein the acrylic pressure-sensitive adhering polymer (A) comprises a structural unit derived from a monomer represented by the following formula (1): CH 2 =CR 1 -C(=O)O-(R 2 O) n -R 3 ... (1) wherein R 1 represents a hydrogen atom or a methyl group, R 2 represents a linear or branched alkylene group having 2 to 6 carbon atoms, R 3 represents a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms, and n represents an integer of 2 to 100.
  4. The active energy ray-curable pressure-sensitive adhesive composition according to claim 1, wherein a glass transition temperature of the acrylic pressure-sensitive adhering polymer (A) is -70°C or more and 0°C or less.
  5. The active energy ray-curable pressure-sensitive adhesive composition according to claim 1, wherein a weight average molecular weight of the acrylic pressure-sensitive adhering polymer (A) is 100,000 or more.
  6. The active energy ray-curable pressure-sensitive adhesive composition according to claim 1, wherein the acrylic pressure-sensitive adhering polymer (A) comprises 50% by mass or more of a structural unit derived from at least one monomer selected from the group consisting of a (meth)acrylic monomer having a boiling point at atmospheric pressure of 150°C or less and a (meth)acrylic monomer having a boiling point at atmospheric pressure of 200°C or more, relative to the entire structural unit of the acrylic pressure-sensitive adhering polymer (A).
  7. The active energy ray-curable pressure-sensitive adhesive composition according to claim 1, comprising the crosslinking agent.
  8. The active energy ray-curable pressure-sensitive adhesive composition according to claim 1, for a semiconductor manufacturing process.
  9. A pressure-sensitive adhesion sheet comprising a pressure-sensitive adhesive layer formed with the active energy ray-curable pressure-sensitive adhesive composition according to any one of claims 1 to 8.
  10. The pressure-sensitive adhesion sheet according to claim 9, wherein a gel fraction based on the acrylic pressure-sensitive adhering polymer (A) in the pressure-sensitive adhesive layer before attachment with an adherend is 90% or less.
  11. The pressure-sensitive adhesion sheet according to claim 9, wherein a weight loss rate at 200°C in the pressure-sensitive adhesive layer, as measured by thermogravimetric measurement in conditions of a rate of temperature rise of 20°C/min and a range of temperature rise of 25 to 350°C, is 5% by weight or less.
  12. The pressure-sensitive adhesion sheet according to claim 9, wherein a ratio (S2/S1) between a release strength (S1) before the pressure-sensitive adhesion sheet attached to an adherend is irradiated with an active energy ray, and a release strength (S2) after the pressure-sensitive adhesion sheet attached to an adherend is irradiated with an active energy ray to allow a gel fraction based on the acrylic pressure-sensitive adhering polymer (A) in the pressure-sensitive adhesive layer to be more than 90% is 0.7 or less.

Description

Technical Field [Cross Reference to Related Application] The present application claims the priority based on Japanese Patent Application No. 2023-108814 filed on June 30, 2023, the entirety of which is herein incorporated by reference. The present disclosure relates to an active energy ray-curable pressure-sensitive adhesive composition and a pressure-sensitive adhesion sheet. Background Art Pressure-sensitive adhesives are processed into various forms such as tapes or labels, and are utilized in a variety of applications. In recent years, in order to deal with advancement in electronic technology, pressure-sensitive adhesion sheets have also been used in manufacturing processes of semiconductor devices in order to improve handleability during semiconductor manufacturing, further increase performance of semiconductor elements, and the like (see, for example, Patent Literature 1 and Patent Literature 2). Patent Literature 1 discloses a pressure-sensitive adhesion tape for heat-resistant temporary bonding, in which a pressure-sensitive adhesive layer is formed which includes a material for pressure-sensitive adhesive layer formation, the material containing an acrylic polymer, an energy ray-polymerizable oligomer, a polymerization initiator, and a crosslinking agent, and the weight loss rate, as determined by thermogravimetric measurement of the polymerization initiator, is a predetermined value or less. Patent Literature 2 discloses a pressure-sensitive adhesion tape provided with a pressure-sensitive adhesive layer including a (meth)acrylic polymer and a photopolymerization initiator having a coefficient of molar absorbance at a wavelength of 385 nm, of a predetermined value or more. These pressure-sensitive adhesion tapes are used for the purposes of temporary fixation and surface protection of electronic components, and these are irradiated with an active energy ray at the time where such fixation and surface protection of electronic components are made unnecessary, and thus are weakened in adhesion strength and exhibit easy releasability. In recent years, as semiconductor devices have been increased in performance and decreased in thickness, there have been proposed FOWLP (Fan Out Wafer Level Package) technologies and three-dimensional stacked semiconductor (3D-IC) technologies as new semiconductor manufacturing technologies. FOWLP is a technology in which a re-wiring layer is formed on a semiconductor wafer to expand a terminal outside of a semiconductor chip, and thus can allow a semiconductor device to be further increased in performance and decreased in thickness. Citation List Patent Literature Patent Literature 1: Japanese Patent Laid-Open No. 2012-31316Patent Literature 2: Japanese Patent Laid-Open No. 2016-89045 Summary of Invention Technical Problem In a semiconductor manufacturing process according to FOWLP, a pressure-sensitive adhesion tape is attached on a support substrate such as glass, a semiconductor chip is placed on a pressure-sensitive adhesive layer of the pressure-sensitive adhesion tape and the semiconductor chip is temporarily fixed on the support substrate, thereafter various stacking steps are further performed to form a stacked body on the support substrate, and thereafter the stacked body including the semiconductor chip is released from the support substrate. Such a method not only allows handleability during semiconductor manufacturing to be improved, but also can allow a semiconductor device to be further decreased in thickness and increased in performance. As the method for releasing the stacked body including the semiconductor chip from the support substrate, a method including utilizing an active energy ray to weaken the adhesion force of the pressure-sensitive adhesive layer by irradiation with such an active energy ray can achieve simplification of a release step and is also industrially useful. The pressure-sensitive adhesion tape used in an application of the semiconductor manufacturing process is demanded to not only exhibit high adhesiveness to an adherend during formation of the stacked body on the support substrate, but also be easily releasable from the support substrate during release of the stacked body including the semiconductor chip, from the support substrate. A heat treatment at a high temperature of, for example, 200°C or more may be applied in the semiconductor manufacturing process, and the pressure-sensitive adhesion tape used in the semiconductor manufacturing process is demanded to hardly cause floating and foaming even against such a heat treatment at a high temperature and be excellent in heat resistance. The present disclosure has been made in view of the above circumstances, and one object thereof is to provide an active energy ray-curable pressure-sensitive adhesive composition capable of forming a pressure-sensitive adhesive layer which exhibits easy releasability due to irradiation with an active energy ray and which is excellent in heat res