KR101109694B1 - adhesive - Google Patents

Abstract

The present invention relates to an adhesive containing a spiro compound

(a) at least one spiro compound selected from compounds represented by the following formula (1) and (2);

(b) thermoplastic resins; And

(c) Adhesive containing crosslinkable component which consists of crosslinkable resin and crosslinking agent or initiator.

The adhesive of the present invention adds a compound containing a spirorthocarbonate (“SOC”) group of Formula 1 and / or a spirorthosilicate (“SOS”) group of Formula 2 to control hardening shrinkage to minimize residual stress. . This action is achieved by expanding and opening the spiro compound by opening and closing the spiro compound in the crosslinking reaction of the adhesive crosslinkable component, thereby suppressing curing shrinkage of the entire adhesive. Therefore, the adhesive of the present invention can control the volume shrinkage at the time of curing without deterioration of other physical properties and reliability compared to the method of alleviating the curing shrinkage and residual stress depending on the content of the existing thermoplastic resin.

Spiro compounds, interconnects, crosslinkable resins, thermal expansion coefficients

Description

Adhesive {adhesive}

The present invention relates to a spiro compound-containing adhesive.

In electronic devices, various adhesives are used for the purpose of joining elements and respective members. Such adhesives require high adhesion, high heat resistance, low hygroscopicity, low coefficient of thermal expansion, high modulus, and excellent reliability, and epoxy or acrylate-based thermosetting resins are widely used to satisfy these various characteristics. (Japanese Patent Laid-Open Publication No. Hei 1-13480, Japanese Patent Laid-Open Publication No. 2002-203427). However, if the adhesive is manufactured using only a thermosetting resin, the hardening process for the circuit connection is performed, and if a defect occurs, the repair is impossible, which causes a problem that the entire device must be discarded, which is not cost effective. . In addition, the thermosetting resin is cured shrinkage of about 3 to 15% by the curing reaction of the adhesive resin in the curing process for the circuit connection, and the resulting curing shrinkage phenomenon generates residual stress in the adhesive resin, resulting in reduced adhesive strength and microcracks. It causes a decrease in reliability due to such problems.

In order to improve hydraulic properties and effectively disperse residual stresses, electronic adhesives are often used in combination with thermosetting resins and thermoplastic resins (especially rubber resins). However, in order to reduce the curing shrinkage to a satisfactory level, a considerable amount (more than about 60%) of thermoplastic resin should be used, and therefore, thermo-mechanical characteristics such as thermal stability, thermal expansion coefficient, and modulus of the entire adhesive by adding a large amount of thermoplastic resin This deterioration and the deterioration of these thermo-mechanical properties are important factors that lower the reliability of the electronic device. In particular, when an adhesive is used to electrically connect a driver IC or a memory chip of a semiconductor device or a display device, such thermo-mechanical properties have a great influence on reliability. For example, an increase in the coefficient of thermal expansion and a decrease in the modulus due to the use of thermoplastic resins cause warpage in the circuit connection process and this warpage degrades the reliability of the module. Korean Patent No. 10-0651323 describes the problem of such warpage (warpage) in detail.

An object of the present invention is to avoid the existing method of controlling the curing shrinkage depending on the content of the thermoplastic resin, and to provide a highly reliable adhesive while functioning as a connecting material by controlling the curing shrinkage effectively without deteriorating other physical properties.

According to the present invention,

(a) at least one spiro compound selected from compounds represented by the following formula (1) and (2);

(b) thermoplastic resins; And

(c) An adhesive comprising a crosslinkable component comprising a crosslinkable resin and a crosslinking agent or an initiator is provided.

In Formula 1, R 1 and R 2 are each a hydrocarbylene or a substituted hydrocarbylene bridge group having two or more bridge carbon atoms, and substituted functional groups are, for example, halo, ether-containing alkoxy, hydroxyl, and the like. . R 1 and R 2 are preferably each independently of the formula -CR 3 R 4 -CR 5 R 6-(CR 7 R 8) n-(wherein n is 0 or 1 and each of R 3, R 4, R 5, R 6, R 7 and R 8 are hydrogen, hydrocarbyl or substituted hydrocarbyl, provided that R 3, R 4, R 5, R 6, R 7 adjacent or paired with each other And two groups of R 8 may together form a ring). R 1 and R 2 are more preferably the same. R 3, R 4, R 5, R 6, R 7 and R 8 are more preferably independently hydrogen, alkyl, in particular alkyl containing 1 to 10 carbon atoms, more preferably methyl, ethyl or hydroxide Hydroxyalkyl, especially hydroxymethyl. In addition, one or more of R1 and R2 may form part of the polymer or oligomer structure or may be linked to the polymer or oligomer structure. "Hydrocarbylene" consists of one or more hydrogen atoms and one or more carbon atoms and represents a divalent moiety (optionally bonded to one or more other moieties) whose free atoms are not bonded to a double bond. That is, hydrocarbylene can be formed by removing two hydrogen atoms from the hydrocarbon (eg, forming alkylene from alkanes).

In Formula 2, X and Y independently represent a linear or branched hydrocarbylene each having a reactive group. Preferably, the hydrocarbylene may have from 2 to 80 carbon atoms, preferably from 2 to 20 carbon atoms, most preferably from 2 to 10 carbon atoms. The hydrocarbylene is one or more hetero-atoms, optionally selected from the group consisting of oxygen, nitrogen, sulfur and phosphorus, and / or amides, thioamides, thioesters, urethanes, ureas, sulfones, sulfoxy, ethers, esters, Epoxy, cyano, halogen, amino, thiol, hydroxyl, nitro, phosphorus, sulfoxy, amido, ether, ester, urea, urethane, thioester, thioamide, amide, carboxyl, carbonyl, aryl, acyl and It may be substituted with one or more groups selected from the group consisting of olefinically unsaturated groups. X and Y, respectively, or X and Y together may form part of a polymer or oligomer structure, or may be linked to a polymer or oligomer structure.

The adhesive of the present invention is for connecting or packaging between electronic components in an electronic device, and the connection and packaging may be electrically or thermally conductive or insulating. Although representatively expressed as an adhesive, the term "adhesive" in the present invention, depending on the purpose of use, sealant, an encapsulant, an encapsulant, an underfill and an opposing circuit for the purpose of protecting the circuit electrode in an electronic device including a display and a semiconductor device. Non-conductive adhesive (NCF) for the electrical connection of the present invention, and also includes anisotropic conductive adhesive (ACF) and isotropic conductive adhesive (ICA) including conductive particles. .

The adhesive of the present invention is preferably based on 100 parts by weight of the thermoplastic resin as component (b), and 50 to 220 parts by weight of the crosslinkable resin component and 0.5 to 50 parts by weight of the initiator or crosslinking agent and spiro as the component (a). It contains 1 to 200 parts by weight of the compound. The spiro compound as the component (a) is most preferably 20 to 100 parts by weight. When there is little addition amount, the reduction of hardening shrinkage is insignificant, but there exists a possibility that the volume may expand | swell more and may inhibit electrical connection. (c) The amount of the crosslinkable resin component added in the curable component is more preferably 70 to 140 parts by weight, more preferably 2 to 20 parts by weight of the initiator or the crosslinking agent. When excessive amount of crosslinkable resin component is used, the adhesive force decreases due to internal stress, and when the initiator is 0.5 parts by weight or less, the curing density is significantly lowered. Therefore, it is not sufficient to secure physical properties, mechanical properties, and thermo-mechanical properties after curing. When the amount is 50 parts by weight or more, problems such as deterioration in storage stability may occur.

The thermoplastic resin (b) used in the present invention may be a known one without particular limitation as long as it is inert with the crosslinking agent of the (C) curable component. For example, there are polyurethane resins, polyimide resins, polyamide resins, polyethylene resins, polypropylene resins, poly (meth) acrylate resins, polyvinyl butyral resins, and resins containing hydroxyl groups, elastomers, and acrylics. Group-containing resins, elastomers and the like may be more preferably used in view of compatibility with other components. Although the molecular weight of a thermoplastic resin does not have a restriction | limiting in particular, Generally, a weight average molecular weight is between 3,000-5,000,000, It is suitable, More preferably, it is especially preferable from the viewpoint of compatibility that it is about 15,000-1,000,000. The spiro compound-containing adhesive of the present invention may be suitably blended with a thermoplastic resin for adjusting the viscosity and wettability in the case of liquid adhesive, and for film formation in the case of a film adhesive.

In the present invention, (c) a crosslinkable component, broadly, an oligomer and prepolymer having two or more reactors as a reactor selected from polymerizable double bonds, epoxy, oxetane, (meth) acryloyl, urethane and urea groups, and the like Accordingly crosslinking agents (curing agents) or initiators can be used. If necessary, a monomer with or without a reactor may be added as a viscosity regulator or a curing regulator.

As the preferred (c) crosslinkable component in the present invention, the crosslinkable resin is an acrylic modified resin having two or more polymerizable double bonds, an initiator or a crosslinking agent, and a thermal initiator and a photoinitiator are used. At this time, the polymerizable double bond is mainly at the terminal of the acrylic modified resin. Examples of acrylic modified resins include acrylic modified resins derived from vinyl copolymers, polyether polyacrylates, polybutadiene diacrylate polyester polyacrylates, polyurethane polyvalent acrylates and polyepoxy polyacrylates. The acrylic modified resin is an oligomer, a prepolymer, and optionally a monomer, for example, glycerol diacrylate, glycerol triacrylate, ethylene glycol diacrylate, diethylene glycol diacrylate, triethylene glycol dimethacrylate. , 1,3-propanediol diacrylate, 1,3-propanediol dimethacrylate, trimethanol triacrylate, 1,2,4-butanetriol trimethylacrylate, 1,4-cyclohexanediol diacryl Latex, pentaerythritol triacrylate, pentaerythritol tetraacrylate, pentaerythritol tetramethacrylate, di-trimethylolpropane tetraacrylate, ethoxylated (4) pentaerythritol tetraacrylate, pentaerythritol Tetraacrylate, dipentaerythritol pentaacrylate, low viscosity dipentaerythritol pentaacrylate , Methacrylate ester, sorbitol hexaacrylate, bis [l- (2-acryloxy)]-p-ethoxyphenyl dimethylmethane, bis [1- (3-acryloxyyl-2-hydroxy)]-p -Propoxyphenyl-dimethylmethane, tris-hydroxyethyl isocyanurate trimethacrylate), bis-acrylates and bis-methacrylates of polyethylene glycol, copolymerizable mixtures of acrylated monomers, acrylated oligomers, polybutadienedi There are 20 or less polyhydric acrylates of acrylate, urethane diacrylate, epoxy diacrylate, and polyester, and single or two or more kinds can be used simultaneously. If necessary, it may further have a vinyl monomer or oligomer type acrylate or methacrylate as a viscosity regulator or a curing regulator.

As an initiator of the said acrylic modified resin, a diacyl peroxide derivative, a peroxy dicarbonate derivative, a peroxy ester derivative, a peroxy ketal derivative, a dialkyl peroxide derivative, a hydroperoxide derivative, a benzoin type compound, acetophenones, for example , Benzophenones, thioxanthones, anthraquinones, α-acyl oxime esters, phenylglyoxylates, benzyls, azo compounds, diphenyl sulfide compounds, acylphosphine oxide compounds, organic pigments A compound, an iron-phthalocyanine type compound, etc. are mentioned. These initiators can be used individually or in mixture of 2 or more components as needed.

The curing agent activated by heat and the curing agent activated by light irradiation can be used individually or in combination, and especially when used in combination, the curing reaction proceeds at the same time by light irradiation and heat. have.

Another preferable (c) crosslinkable component of this invention is a hardening | curing agent of an epoxy resin and an epoxy resin. Examples of the epoxy resins include bisphenol-A epoxy resins, bisphenol-F epoxy resins, bisphenol-S epoxy resins, phenol novolac epoxy resins, cresol novolac epoxy resins, bisphenol-A novolac epoxy resins, Bisphenol-F novolac epoxy resin, cycloaliphatic epoxy resin, glycidyl ester epoxy resin, glycidylamine epoxy resin, hydantoin epoxy resin, isocyanate epoxy resin, aliphatic epoxy resin, and the like. . These epoxy resins can also be substituted with halogen or hydrogen, can be used alone or two or more kinds at the same time.

The crosslinking agent (curing agent) of the epoxy resin has the potential to crosslink or cure the epoxy resin by heat and / or light irradiation, and anionic or cationic polymerizable catalytic crosslinking agents and polyaddition crosslinking agents alone or two kinds thereof. It can be used as a mixture of the above.

As an anion or cationically polymerizable catalytic crosslinking agent, tertiary amines, imidazoles, hydrazide compounds, boron trifluoride-amine complexes, onium salts (sulfonium salts, ammonium salts), phosphonium compounds, amineimides, diaminomals Rheonitrile, melamine (derivatives), polyamine salts, dicyandiamide, and the like, and modified substances thereof can also be used. Examples of the polyaddition type crosslinking agent include polyamines, polymer captans, polyphenols, and acid anhydrides. In particular, cationic polymerizable catalyzed crosslinking agents such as onium salts (aromatic diazonium salts, aromatic sulfonium salts, etc.) can crosslink epoxy resins by light irradiation, thereby enabling rapid crosslinking at low temperatures.

Epoxy resin crosslinking agent activated by heat and epoxy resin crosslinking agent activated by light irradiation can be used either individually or in combination. Especially, when used in combination, the crosslinking reaction proceeds at the same time by light irradiation and heat, so that rapid crosslinking is possible at low temperature. Therefore, it is more preferable.

The crosslinking agent which crosslinks epoxy resin is coated with a high molecular compound such as polyurethane or polyester and microencapsulated to ensure stable potential.

In the present invention (c) as a crosslinkable component, acrylic modified resin and epoxy resin may be used in combination, and other initiators or crosslinking agents may be used simultaneously. In this case, the slow crosslinking speed, which is a disadvantage of the epoxy resin, can be supplemented with a radical polymerizable material, and an epoxy resin can be obtained in terms of process and reliability by supplementing the thermo-mechanical properties, which are a disadvantage of the radical polymerizable material. There is an advantage. Thermal initiators are generally 80-200 The photoinitiator at 占 폚 is activated by light irradiation at 150 to 750 nm.

The conductive particles used in the present invention may be applied according to the purpose that the average particle diameter is 2 ~ 30 micrometers, generally using metal particles such as gold, silver, nickel, copper, solder, or on the organic or inorganic particles The electroconductive particle which coated the metal thin film, and the electroconductive particle which coated the insulating layer further can be used. It is preferable that the said electroconductive particle uses 1-30 volume parts of the said electroconductive particle with respect to 100 volume parts of adhesive compositions.

In addition, additives, phosphorus adhesion promoters, antioxidants, and coupling agents for improving processability, such as known adhesion enhancers, inorganic pigments, and organic dyes, which are not particularly limited in order to function as circuit connecting materials having proper processability and excellent reliability for various substrates. Additives such as and the like may be further used, and the amount of the additive is preferably less than 5 parts by weight based on 100 parts by weight of the total adhesive composition.

In the present invention, the adhesive, depending on the application method, may be formed in a liquid or film form and may have a multilayer structure of one or more layers and the thickness of each layer may vary depending on the purpose of use, but preferably 5 ~ 50um to be. When forming the film-like multilayer structure, the layer including the conductive particles and the layer not containing the conductive particles may be mixed and formed. In the present invention, the adhesive is different depending on the application method, but is preferably made under a pressure of 10 seconds or less, a heating temperature of 80 to 200 degrees, and a pressure of 0.1 to 5 MPa. The maximum value of the connection resistance value between the said circuit electrodes after heat crimp is preferably 3 times or less with respect to the minimum value.

The adhesive of the present invention adds a compound containing a spirorthocarbonate (“SOC”) group of Formula 1 and / or a spirorthosilicate (“SOS”) group of Formula 2 to control hardening shrinkage to minimize residual stress. . This action is achieved by expanding and opening the spiro compound by opening and closing the spiro compound in the crosslinking reaction of the adhesive crosslinkable component, thereby suppressing curing shrinkage of the entire adhesive. Therefore, the adhesive of the present invention can control the volume shrinkage at the time of curing without deterioration of other physical properties and reliability compared to the method of alleviating the curing shrinkage and residual stress depending on the content of the existing thermoplastic resin.

The invention can be better understood by the following examples, the following examples are intended to illustrate the invention and should not be construed as limiting the protection scope of the invention.

Example 1.

(a) spirorthocarbonate (SOC): 10 parts by weight of 1,6-dioxaspiro [4,4] nonane-2,7-dione (Aldrich), (b) thermoplastic resin: phenoxy resin (YP-50, Kukdo Chemical 25 parts by weight and 15 parts by weight of acrylic rubber (SG-80H, Nagase Chemtex), (c) crosslinkable resin: 20 parts by weight of epoxy resin (RKB 4110, Regina Chemical), crosslinking agent (hardener): latent thermal activity 5 parts of hardener (HX-3932HP, Asahi Chemical) 20 parts by weight, and (d) conductive particles: 10 parts by weight of Au / Ni coated resin balls (AUL-704, Sekisui), toluene (80%) and methylethyl The mixture was uniformly mixed with ketone (20%) in a solid content of 60%, coated on a white PET film subjected to release and antistatic treatment, and dried in an 80 ° C. dryer to prepare an adhesive having a thickness of 25 micrometers.

Example 2.

(a) spirorthocarbonate (SOC): 10 parts by weight of 3,9-divinyl-2,4,8,10-tetraoxaspiro [5,5] undecane (Aldrich), (b) thermoplastic resin: phenoxy resin (YP- 50, Kukdo Chemical) 25 parts by weight and 15 parts by weight of acrylic rubber (SG-80H, Nagase Chemtex), (c) crosslinkable resin: 20 parts by weight of urethane dimethacrylate resin (CN-1963, Satomer), crosslinking agent (Hardening agent 0: 2 parts by weight of a thermally active radical initiator (benzoyl peroxide, Aldrich), and (d) conductive particles: 10 parts by weight of Au / Ni coated resin ball (AUL-704, Sekisui) toluene ( 80%) and methyl ethyl ketone (20%), uniformly mixed with 60% solids, coated on a white PET film that is releasing and antistatic, and then dried in an 80 ° C dryer to a thickness of 25 micrometers. Was prepared.

Example 3.

(a) spirorthocarbonate (SOC): 5 parts by weight of 1,6-dioxaspiro [4,4] nonane-2,7-dione (Aldrich) and 3,9-divinyl-2,4,8,10-tetraoxaspiro [ 5,5] undecane (Aldrich) 5 parts by weight, (b) thermoplastic resin: 25 parts by weight of phenoxy resin (YP-50, Kukdo Chemical) and 15 parts by weight of acrylic rubber (SG-80H, Nagase Chemtex), (c ) Crosslinkable Resin: 10 parts by weight of epoxy resin (RKB 4110, Regina Chemical) and 10 parts by weight of urethane dimethacrylate resin (CN-1963, Satomer), initiator or crosslinking agent: thermally active cationic initiator (WPI-113, Waco) 2 parts by weight and 2 parts by weight of a photoactive radical initiator (Irgacure 250, Chivas Specialty Chemical), and (d) conductive particles: Au / Ni coated resin balls (AUL-704, Sekisui) 10 parts by weight of toluene ( 80%) and methyl ethyl ketone (20%) uniformly mixed with 60% solids, coated on a white PET film subjected to release and antistatic treatment, and then dried in a dryer at 80 ° C. To prepare a 25-micrometer adhesive.

Comparative Example 1.

An adhesive was prepared in the same manner as in Example 1 except that no spirortocarbonate (SOC) compound was added.

Comparative Example 2

A connection material was prepared in the same manner as in Example 1 except that the spirortocarbonate (SOC) compound was replaced with silicone rubber particles (TOSPEARL T-120, particle size 2 micrometer, Momentive performance materials).

Comparative Example 3

An adhesive was prepared in the same manner as in Example 2 except that no spirortocarbonate (SOC) compound was added.

Comparative Example 4

An adhesive was prepared in the same manner as in Example 2 except that the spirortocarbonate (SOC) compound was replaced with silicone rubber particles (TOSPEARL T-120, particle size 2 micrometer, Momentive performance materials).

Comparative Example 5

An adhesive was prepared in the same manner as in Example 3 except that no spirortocarbonate (SOC) compound was added.

Comparative Example 6.

A connection material was prepared in the same manner as in Example 3 except that the spirortocarbonate (SOC) compound was replaced with silicone rubber particles (TOSPEARL T-120, particle size 2 micrometer, Momentive performance materials).

The circuit connection materials prepared in Examples and Comparative Examples were evaluated for curing shrinkage, adhesion, connection resistance, thermal expansion coefficient, modulus, and the like. In particular, the adhesion and connection resistance of the fabricated circuit connection material were evaluated using an ITO coated glass substrate and FPC (PI 75 μm, Au finished Cu 35 μm, 250 μm pitch). After the connection material was temporarily fixed at 80 ° C., 2 seconds, and 1 MPa on ITO glass, in Example 1, Comparative Examples 1 and 2, the conditions of Example 2, Comparative Example 3, and 180 ° C., 10 seconds, and 3 MPa were used. In the case of 4, the conditions of 150 ℃, 5 seconds, 3 MPa, and finally in Example 3, Comparative Examples 5 and 6 in the case of thermocompression bonding at 150 ℃, 5 seconds, 3 MPa and irradiated with 365nm ultraviolet light The connection process was performed.

Table 1 below summarizes the evaluation results of the circuit connection materials of the respective comparative examples and examples.

Table 1.

Process conditions Experimental Example Hardening shrinkage
(%) Adhesion
(kgf / cm) Connection resistance
(Ω) Coefficient of thermal expansion
(ppm / ℃) Modulus
(GPa at 20 ℃) 180 ° C., 10 seconds, 3 MPa Example 1 0.2 1332 0.35 67 1.8 Comparative Example 1 2.1 1123 0.31 81 1.4 Comparative Example 2 0.4 1392 0.49 112 0.9 150 ° C., 5 seconds, 3 MPa Example 2 0.9 1021 0.47 71 1.6 Comparative Example 3 1.8 983 0.35 98 1.2 Comparative Example 4 0.8 1121 0.52 134 0.8 150 ℃ heating + 365nm UV irradiation, 5 seconds, 3 MPa Example 3 0.6 1056 0.39 77 1.2 Comparative Example 5 1.9 981 0.31 94 1.3 Comparative Example 6 0.8 1123 0.57 153 0.8

As shown in Table 1, in Examples 1, 2, and 3 containing a spirortocarbonate (SOC) compound, the curing shrinkage rate compared to Comparative Examples 1, 3, and 5 that do not contain a spirortocarbonate (SOC) compound It can be seen that this is significantly reduced. In addition, compared with Comparative Examples 2, 4, and 6 in which silicone rubber particles were added instead of spirortocarbonate (SOC) compounds, when the silicone rubber particles were added, the residual stress due to the decrease in curing shrinkage rate could be expected, but thermal expansion was expected. While it is not preferable in terms of thermo-mechanical properties such as modulus and modulus, the addition of spirortocarbonate compounds can effectively reduce hardening shrinkage without deteriorating thermo-mechanical properties to secure adhesion and connection resistance. It will be possible to produce adhesives that function as interconnects.

Claims (11)

delete delete delete delete delete delete delete (a) 1 to 200 parts by weight of one or more spiro compounds selected from compounds represented by Formula 1 and Formula 2 below; (b) 100 parts by weight of thermoplastic resin; And (c) Adhesive used as an electrical connection material further containing 1-30 volume parts of electroconductive particle with respect to 100 volume parts of adhesive agents which consist of 50-200 weight part of crosslinkable resins, and a crosslinking component which consists of 0.5-50 weight part of crosslinking agents or an initiator.

R 1 and R 2 in formula 1 are each a hydrocarbylene or substituted hydrocarbylene bridge group having two or more bridge carbon atoms. In Formula 2, X and Y are each independently a linear or branched hydrocarbylene having 2 to 80 carbon atoms having a reactive group. The adhesive according to claim 8, further comprising at least one additive selected from the group consisting of a coupling agent, an organic filler and an inorganic filler, and a polymerization inhibitor. delete delete