Dual-cure adhesive composition

Abstract

The present invention provides a dual-cure adhesive composition comprising: (A) at least one isocyanate-terminated polyurethane prepolymer; (B) at least one radically polymerizable compound; (C) at least one photoinitiator; and (D) at least one moisture-cure catalyst, wherein the composition exhibits a loss factor value of greater than 0.6 at room temperature, as measured according to ASTM D4440-15, after 60 seconds of irradiation with ultraviolet light having a wavelength of 375 nm and an intensity of 50 mW / cm.

Description

[Technical Field]

[0001] Technical Field The present invention relates to a dual-cure adhesive composition and its use. In particular, the present invention relates to a dual-cure adhesive composition that exhibits significant compressibility after exposure to ultraviolet light and its use. [Background technology]

[0002] Background of the Invention Ultraviolet (UV) curable adhesives are widely used for structural bonding in consumer electronics due to their fast curing speed and high adhesive strength, but typically require UV-transparent substrates.

[0003] Alternative bonding technologies, such as moisture-curing polyurethane adhesives, two-component structural adhesives, and heat-curing epoxy adhesives, have been adopted to bond substrates that are opaque to UV light. However, these technologies have various drawbacks. For example, moisture-curing adhesives cannot achieve the fast curing speeds required to meet the demand for improved production assembly efficiency in the electronics industry. Furthermore, two-component structural adhesives complicate the assembly process. Furthermore, heat-curing epoxy adhesives are not suitable for bonding heat-sensitive substrates because high temperatures can cause deformation of the substrate material.

[0004] Dual-cure adhesives containing both UV-curable and moisture-curable compositions have been proposed in the prior art as a viable method for achieving fast curing in bonding non-UV-transparent substrates. These dual-cure adhesives generally consist of a polyurethane prepolymer as the moisture-curable compound, a (meth)acrylate as the polymerizable group, and a photoinitiator. To activate UV-curable adhesive components, UV irradiation is required before laminating the UV-opaque substrate to the adhesive composition as part of the assembly process. However, if the "semi-cured" adhesive (where the UV portion has cured but the moisture-curable portion has not yet begun to cure) does not have sufficient compressibility, it can be difficult to work with and make lamination difficult. The prior art does not address this technical problem. Summary of the Invention [Problem to be solved by the invention]

[0005] In view of the above, there remains a need for the development of dual-cure adhesive compositions that exhibit significant compressibility after UV irradiation without compromising fast cure speed and adhesive strength during simultaneous curing. [Means for solving the problem]

[0006] Summary of the Invention According to a first aspect of the present invention, there is provided herein a method for producing a medicament for a medicament comprising: (A) at least one isocyanate-terminated polyurethane prepolymer; (B) at least one radically polymerizable compound; (C) at least one photoinitiator, and (D) at least one moisture-cure catalyst; A dual cure adhesive composition comprising: Here, the wavelength is 375 nm and the intensity is 50 mW / cm 2 and a dual-cure adhesive composition, wherein the composition has a loss factor value of greater than 0.6 as measured at room temperature according to ASTM D4440-15 after 60 seconds of exposure to ultraviolet light.

[0007] According to a second aspect of the present invention, there is provided a laminate comprising a first substrate, a second substrate, and an adhesive layer disposed therebetween, wherein the first and second substrates are independently selected from glass, resin, and metal, and preferably at least one of the two substrates is non-UV transparent, and the adhesive layer is formed by curing the adhesive composition of the present invention.

[0008] According to a third aspect of the present invention there is provided an electronic device comprising a laminate of the present invention or manufactured using an adhesive composition according to the present invention.

[0009] According to a fourth aspect of the present invention, there is provided the use of an adhesive composition according to the present invention or a laminate according to the present invention in the manufacture of an electronic device.

[0010] Other features and aspects of the subject matter are described in more detail below. [Brief explanation of the drawings]

[0011] Brief description of the diagram [Figure 1] FIG. 1 shows the rheological curves of Example 1 and Comparative Example 1 measured using an Anton Paar modular compact rheometer MCR 302e. DETAILED DESCRIPTION OF THE INVENTION

[0012] Detailed Description of the Invention Those skilled in the art will appreciate that the present invention is merely a description of exemplary embodiments and is not intended to limit the broader aspects of the present invention. Each aspect so described may be combined with other aspects unless expressly indicated to the contrary. In particular, any feature indicated as being preferred or advantageous may be combined with any other feature indicated as being preferred or advantageous.

[0013] Unless otherwise specified, in the context of the present invention, the terms used shall be construed in accordance with the following definitions.

[0014] Unless otherwise specified, the terms "a," "an," and "the" as used herein include both the singular and the plural.

[0015] As used herein, the terms "comprising" and "comprises" are synonymous with "including," "includes," or "containing," and "contains," and are inclusive or open-ended and do not exclude additional, unrecited members, elements, or process steps.

[0016] The terms "at least one" or "one or more" used herein to define a component refer to the type of component, not the absolute number of molecules. For example, "one or more polyols" refers to one type of polyol or a mixture of multiple different polyols.

[0017] The term "ultraviolet rays (irradiation)" used here means ultraviolet rays (irradiation) with a wavelength of 200 to 410 nm.

[0018] As used herein, "amorphous" means the absence of a melting transition as measured by differential scanning calorimetry (DSC).

[0019] As used herein, the term "crystalline" means having a melting transition as measured using differential scanning calorimetry (DSC).

[0020] As used herein, the term "room temperature" refers to a temperature of about 20°C to about 25°C, preferably about 25°C.

[0021] As used herein, the term "oligomer" refers to a low molecular weight polymer containing 10 to less than 100 repeating units of the same or different types.

[0022] The term "polymer" refers to a polymeric compound composed of repeating units of the same or different types. The term "polymer" includes homopolymers and copolymers. The term "copolymer" should be understood as a polymer derived from two or more monomers; that is, the term "copolymer" includes bipolymers, terpolymers, tetrapolymers, etc. Additionally, the term "monomer" in this disclosure is distinguished from polymers and refers to a compound having a weight average molecular weight (Mw) of 2,000 or less.

[0023] Unless otherwise specified, the recitation of numerical endpoints includes not only the recited endpoint but also all numerical values ​​and fractions within each range. Molecular weights refer to number average molecular weights (Mn) unless otherwise stated. Unless otherwise specified (e.g. according to DIN 55672), all molecular weight data refer to values ​​obtained by gel permeation chromatography (GPC).

[0024] All references cited herein are incorporated by reference in their entirety.

[0025] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the meaning commonly understood by one of ordinary skill in the art to which this invention belongs.

[0026] In one aspect, the present disclosure generally comprises: (A) at least one isocyanate-terminated polyurethane prepolymer; (B) at least one radically polymerizable compound; (C) at least one photoinitiator, and (D) at least one moisture-cure catalyst; wherein the composition after 60 seconds of irradiation with ultraviolet light having a wavelength of 375 nm and an intensity of 50 mW / cm2 has a loss factor of greater than 0.6, as measured at room temperature according to ASTM D4440-15.

[0027] Loss Factor Value According to the present invention, the wavelength is 375 nm and the intensity is 50 mW / cm 2 The dual cure adhesive composition after 60 seconds of exposure to UV light has a loss factor value of greater than 0.6 when measured at room temperature according to ASTM D4440-15.

[0028] Within the above ranges, the adhesive composition after irradiation is easy to compress and its mechanical properties further improve during the subsequent moisture curing period of several hours, thus ensuring a wide time window of workability.

[0029] In the present invention, the loss factor (i.e., damping value) tan δ is obtained by a rheological curve measured with a rheometer equipped with a UV light source according to the dynamic oscillation test of ASTM D4440-15, where the rheometer can be a Modular Compact Rheometer MCR 302e or other types of rheometers from Anton Paar, and the UV light source can be a Lumen Dynamics Omnicure Series 1000. The measurement is carried out at a frequency of 10 rad / s.

[0030] Supplementary measurements in accordance with ASTM D4440-15 are carried out as follows: First, a dual-cure adhesive composition sample is held using a plate clamp with a diameter of 25 mm and a thickness of 1 mm, and rheological measurements are carried out in vibration mode at room temperature with a frequency of 10 rads and a strain of 0.01% or less for a period of time to stabilize the sample. Then, a LUMEN DYNAMICS OmniCure SERIES 1000 is used to measure the rheological properties of the adhesive composition at a wavelength of 375 nm and an intensity of 50 mW / cm. 2UV irradiation is started for 60 seconds, and then stopped. The storage modulus G' and loss modulus G'' within the time range can be obtained. Furthermore, the loss factor value (i.e., damping value) tanδ at each time point is calculated from the storage modulus G' and loss modulus G'' according to the following equation. tan δ=G'' / G'

[0031] The measurement process described above records a series of time-dependent loss factor values, forming a rheological curve that may vary over time because the moisture curing process lags behind the UV curing. Note that the loss factor in this context refers to the value of the loss factor immediately after UV exposure has ended.

[0032] Preferably, the dual-cure adhesive composition of the present invention is applied at a wavelength of 375 nm and an intensity of 50 mW / cm 2 After 60 seconds of exposure to UV light, the loss factor measured in accordance with ASTM D4440-15 at room temperature is 0.7 or greater but less than 1.1, and the cured product has excellent cross tensile strength.

[0033] (A) Isocyanate-terminated polyurethane prepolymer In accordance with the present invention, a dual-cure adhesive composition comprises (A) at least one isocyanate-terminated polyurethane prepolymer.

[0034] The specific type of isocyanate-terminated polyurethane prepolymer is not particularly limited, and may be a reaction mixture containing at least one polyether polyol and at least one polyisocyanate having at least two isocyanate groups per molecule.

[0035] In terms of the primary reactants, useful polyether polyols are derived from oxide monomers (e.g., ethylene oxide, propylene oxide, 1,2-butylene oxide, 1,4-butylene oxide, tetrahydrofuran, and combinations thereof) and polyol initiators (e.g., ethylene glycol, propylene glycol, butanediol, hexanediol, glycerol, trimethylolethane, trimethylolpropane, pentaerythritol, and combinations thereof). Preferably, the polyether polyols have a molecular weight (Mn) of 100 g / mol to 8000 g / mol, 200 g / mol to 4000 g / mol, or even 200 g / mol to 2000 g / mol.

[0036] In a preferred embodiment, at least two polyether polyols having molecular weights (Mn) of 200 g / mol to 2000 g / mol can be used as reactants to prepare component (A). In the present invention, when two or more polyether polyols are used as a mixture in the reaction, the molecular weights (Mn) of each polyether polyol may be within the above range.

[0037] In a preferred embodiment, at least one polyhydrofuran is used as the polyether polyol to prepare the isocyanate-terminated polyurethane prepolymers used in the present invention. The term "polyhydrofuran" is interchangeable with poly(tetramethylene ether) glycol (PTMEG), which has the chemical formula HO-(-(CH2)4O-). n Polytetrahydrofuran can be produced by cationic ring-opening polymerization of tetrahydrofuran. Polytetrahydrofuran is available, for example, from PTG Co., Ltd. in Korea under the trade names PTMEG 1000, PTMEG 1800, PTMEG 2000, and PTMEG 3000, and from BASF under the trade name PolyTHF TM 2000, PolyTHF TM 1000, PolyTHF TM It is sold commercially as the 650S.

[0038] In a particularly preferred embodiment, the polyether polyol can be present in an amount of 10 to 85%, preferably 20 to 75% by weight, based on the total weight of the isocyanate-terminated polyurethane prepolymer.

[0039] With respect to other primary reactants, polyisocyanates useful in the present invention include the following: aliphatic polyisocyanates, such as hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), hydrogenated diphenylmethane diisocyanate, 1,6-diisocyanato-2,4,4-trimethylhexane, 1,4-cyclohexane diisocyanate (CHDI), 1,4-cyclohexanebis(methyleneisocyanate) (BDI), 1,3-bis(isocyanatomethyl)cyclohexane (H6XDI), dicyclohexylmethane diisocyanate (H12 MDI; aromatic polyisocyanates, such as diphenylmethane diisocyanate compounds (MDI) and their isomers (e.g., diphenylmethane 4,4'-diisocyanate, diphenylmethane-2,2'-diisocyanate, diphenylmethane-2,4'-diisocyanate, oligomeric methylene isocyanates having the formula: JPEG2025541927000001.jpg2980

[0040] (wherein n is an integer from 0 to 5, and mixtures thereof), carbodiimide-modified MDI, naphthalene diisocyanate and its isomers (e.g., 1,5-naphthalene diisocyanate (NDI)), triphenylmethane triisocyanate isomers (e.g., triphenylmethane-4,4',4''-triisocyanate), toluene diisocyanate compounds (TDI) and its isomers, 1,3-xylylene diisocyanate (XDI), tetramethylxylylene diisocyanate (TMXDI) (e.g., p-1,1,4,4-tetramethylxylylene diisocyanate (p-TMXI), m-1,1,3,3-tetramethylxylylene diisocyanate (m-TMXDI)), and mixtures thereof.

[0041] Preferably, the molar ratio of isocyanate groups to hydroxy groups in the composition used to prepare the polyurethane prepolymer is from 1.5 to 2.8, preferably from 1.8 to 2.3.

[0042] In a particularly preferred embodiment, the polyisocyanate can be present in an amount of from 15% to 90%, preferably from 20 to 80% by weight, based on the total weight of the isocyanate-terminated polyurethane prepolymer.

[0043] In addition to the two main reactants, a trace amount of amorphous polyester polyol can be optionally contained as a co-reactant for forming the polyurethane prepolymer of the present invention. This can also be expressed as the amorphous polyester polyol being optionally contained in a trace amount in the polyurethane prepolymer. For example, the amorphous polyester polyol can be optionally contained in the polyurethane prepolymer in an amount of less than 30 wt %, preferably 0 to 20 wt %, based on the total weight of the isocyanate-terminated polyurethane prepolymer.

[0044] When the amorphous polyester polyol is used as one of the reactants, the molecular weight (Mn) may be 500 g / mol to 10,000 g / mol, 600 g / mol to 7000 g / mol, or 700 g / mol to 6000 g / mol. In the present invention, when two or more amorphous polyester polyols are used as a mixture in the reaction, the molecular weight (Mn) of each amorphous polyester polyol may be in the above range.

[0045] When used as one of the reactants, the amorphous polyester polyol can be liquid or solid. When a solid one is used, it preferably has a softening point of 80°C or less, preferably 60°C or less, for example, 60°C, 80°C, or 100°C.

[0046] As used herein, amorphous polyester polyols are or include the reaction product of one or more polyacids and one or more polyols.

[0047] The one or more polyacids can be selected from terephthalic acid (TPA), isophthalic acid (IPA), phthalic acid (PA), methylhexahydrophthalic acid, methyltetrahydrophthalic acid, hexahydrophthalic acid, tetrahydrophthalic acid, maleic acid, succinic acid, glutaric acid, adipic acid (AA), pimelic acid, suberic acid, azelaic acid, sebacic acid, chlorendic acid, 1,2,4-butanetricarboxylic acid, decanedicarboxylic acid, octadecanedicarboxylic acid, dimer acid, dimer fatty acid, trimer fatty acid, fumaric acid, 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, anhydrides of the above acids, and combinations thereof. Preferably, the one or more polyacids can be selected from terephthalic acid, isophthalic acid, phthalic acid, adipic acid, and anhydrides thereof.

[0048] The one or more polyols may be ethylene glycol (EG), propanediol (including 1,2- or 1,3-propanediol), butanediol (including 1,2- or 2,3- or 1,3- or 1,4-butanediol), butenediol (including 1,3- or 2,3- or 1,4-butenediol), butynediol (including 1,4-butynediol), pentanediol (including 1,2-, 1,3-, 1,4-, 1,5-pentanediol), pentenediol, pentynediol, hexanediol (HD) (including 1,2- or 1,3- or 1,4- or 1,5- or 1,6- or 2,3- or 2,4- or 2,5- or 2,6- or 3,4-hexanediol), octanediol (including 1,2-, 1,3-, 1,4-, 1,5-, ...3- or 2,4- or 2,5- or 2,6- or 3,4- 1,7-, 1,8-hexanediol), nonanediol, decanediol, neopentyl glycol (NPG), diethylene glycol (DEG), triethylene glycol, tetraethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, cyclohexanedimethanol, cyclohexanediol, dimer diol, bisphenol A, bisphenol F, hydrogenated bisphenol A, hydrogenated bisphenol F, glycerol, tetramethylene glycol, polytetramethylene glycol, 3-methyl-1,5-pentanediol, 2-methyl-1,8-octanediol, trimethylolpropane, pentaerythritol, sorbitol, glucose, and combinations thereof. Preferably, the one or more polyols may be selected from hexanediol (including 1,2- or 1,3- or 1,4- or 1,5- or 1,6- or 2,3- or 2,4- or 2,5- or 2,6- or 3,4-hexanediol), ethylene glycol, neopentyl glycol, diethylene glycol.

[0049] Furthermore, a trace amount of polycarbonate polyol can be optionally contained as a co-reactant for forming the polyurethane prepolymer of the present invention. For example, the polycarbonate polyol can be contained in the polyurethane prepolymer in an amount of less than 30% by weight, preferably 0 to 20% by weight, based on the total weight of the isocyanate-terminated polyurethane prepolymer.

[0050] The term "polycarbonate polyol" is understood to have the repeating unit -OC(=O)-O- and terminated with one or more, preferably two, hydroxyl groups. Polycarbonate polyols can be solid or liquid at room temperature.

[0051] Polycarbonate polyols can be prepared, for example, by reacting an aliphatic polyol such as propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexenediol, diethylene glycol, triethylene glycol, or mixtures thereof, with a diaryl carbonate or dialkyl carbonate, such as dimethyl carbonate.

[0052] Polycarbonate polyols are commercially available, for example, Duranoll from Asahi Kasei Corporation. TM It is sold as a product series under the trade name "Duranol". TM T5652, Duranol TM T5651, Duranol TM T5650J, Duranol TM T5650E, Duranol TM T4672, Duranol TM T4671, Duranol TM T4692, Duranol TM T4691, Duranol TM T6001, Duranol TM T6002, Duranol TM G3452, and Duranol TM One example is the G3450J.

[0053] In a particularly preferred embodiment, the reaction mixture for preparing component (A) comprises, based on the total weight of the reaction mixture: 10 to 85% by weight, preferably 20 to 80% by weight, of a polyether polyol; 0 to 30% by weight, preferably 0 to 20% by weight, of an amorphous polyester polyol; 0 to 30% by weight, preferably 0 to 20% by weight, of polycarbonate diol, and 15% to 90% by weight, preferably 20% to 80% by weight, of a polyisocyanate having at least two isocyanate groups per molecule.

[0054] Particularly preferably, component (A) may be present in an amount of 5% to 90% by weight, preferably 10% to 80% by weight, based on the total weight of the adhesive composition.

[0055] (B) Free radical polymerizable compound In accordance with the present invention, the dual-cure adhesive composition includes (B) at least one free-radically polymerizable compound.

[0056] There are no particular limitations on the specific type of free-radically polymerizable compound. The free-radically polymerizable group component (B), i.e., the component that undergoes polymerization initiated by free radicals, is a useful free-radically polymerizable component. Useful free-radically polymerizable components are (meth)acrylate or (meth)acrylamide monomers, oligomers, and / or polymers; these may be monofunctional or polyfunctional materials, i.e., have 1, 2, 3, 4, 5, 6, 7, 8, 9, 10...20...30...40...50...100 or more functional groups that are polymerizable by free radical initiation, and may include aliphatic, aromatic, alicyclic, arylaliphatic, heterocyclic moieties, or combinations of these groups. The term "monofunctional" refers to the inclusion of one photoreactive acrylate functional group, and the term "polyfunctional" refers to the inclusion of two or more photoreactive acrylate functional groups. The free radical polymerizable compound can be selected from (meth)acrylate monomers, (meth)acrylamide monomers, (meth)acrylate oligomers, (meth)acrylamide oligomers, (meth)acrylate polymers, (meth)acrylamide polymers, and combinations thereof, and preferably can be selected from monofunctional (meth)acrylate monomers, monofunctional (meth)acrylamide monomers, monofunctional urethane (meth)acrylate oligomers, difunctional urethane (meth)acrylate oligomers, and combinations thereof.

[0057] In some embodiments, component (B) can have at least one (meth)acrylate or (meth)acrylamide monomer, which can include an aliphatic, aromatic, cycloaliphatic, arylaliphatic, heterocyclic moiety, or any combination thereof.

[0058] In the present invention, "(meth)acrylate" means both or either of acrylate and methacrylate, "(meth)acrylic" means both or either of acrylic and methacrylic, "(meth)acryloyl" means both or either of acryloyl and methacryloyl, and "(meth)acrylamide" means both or either of acrylamide and methacrylamide.

[0059] In the present invention, preferably, a monofunctional (meth)acrylate monomer and / or a monofunctional (meth)acrylamide monomer can be used. Compared to difunctional or higher functional (meth)acrylate monomers and (meth)acrylamide monomers, monofunctional (meth)acrylate monomers and (meth)acrylamide monomers have a low crosslink density, and the adhesive composition after irradiation is easily compressed. In one embodiment of the present invention, the weight average molecular weight (Mw) of the (meth)acrylate monomer or (meth)acrylamide monomer is 2,000 or less.

[0060] More preferably, alicyclic (meth)acrylate monomers and / or alicyclic (meth)acrylamide monomers can be used in the present invention. Adhesive compositions containing alicyclic (meth)acrylate monomers and / or alicyclic (meth)acrylamide monomers are easily compressed after UV irradiation and have higher lap shear strength when cured.

[0061] The type of (meth)acrylate monomer or (meth)acrylamide monomer is not particularly limited, and those commonly used in adhesives can be used. Preferably, the (meth)acrylate monomer or (meth)acrylamide monomer is selected from the group consisting of butyl (meth)acrylate, isodecyl acrylate, phenoxyethyl acrylate, 3,3,5-trimethylcyclohexyl acrylate, 2-[[(butylamino)carbonyl]oxy]ethyl acrylate, and mixtures thereof.

[0062] In some embodiments, component (B) can have at least one urethane (meth)acrylate oligomer, which may include an aliphatic, aromatic, cycloaliphatic, arylaliphatic, heterocyclic moiety, or any combination thereof.

[0063] As used herein, the term "urethane acrylate oligomer" refers to an acrylate oligomer containing at least one urethane bond. The general structure of a urethane group is -O-(CO)-NR-, where (CO) defines a carbonyl group C=O and R is hydrogen or an alkyl group.

[0064] According to an exemplary embodiment of the present invention, the dual-cure adhesive composition includes a polycarbonate-based urethane (meth)acrylate oligomer. The polycarbonate-based (meth)urethane acrylate oligomer is an oligomer that has both a polycarbonate chemical structure and a urethane chemical structure, and can be produced, for example, by reacting a polycarbonate polyol with an isocyanate compound having a (meth)acrylate group. As described above, by using an oligomer having both a polycarbonate structure and a urethane structure, the dual-cure adhesive composition can exhibit superior adhesive strength compared to oligomers that do not have both a polycarbonate chemical structure and a urethane chemical structure.

[0065] Preferably, the urethane (meth)acrylate oligomer may be monofunctional and / or difunctional. In one embodiment of the present invention, the urethane acrylate oligomer has a weight average molecular weight (Mw) of 800 to 100,000 g / mol.

[0066] The type of urethane (meth)acrylate oligomer is not particularly limited, and those generally used in adhesives can be used. Preferred examples of the urethane (meth)acrylate oligomer include, but are not limited to, polybutadiene urethane acrylate oligomer, polyester-based urethane acrylate oligomer, polyether-based urethane acrylate oligomer, polycarbonate-based urethane acrylate oligomer, and polycaprolactone urethane acrylate oligomer.

[0067] The above free radical polymerizable compounds may be used alone or in combination of two or more.

[0068] Commercially available examples of component (B) include urethane (meth)acrylate oligomers such as polycarbonate-based urethane diacrylate oligomer under the trade name CN8888NS, polyester / polyether urethane diacrylate oligomer under the trade name CN981, polyester-based urethane diacrylate oligomers under the trade names CN991, CN964, CN965, CN962, and CN966J75, and (meth)acrylate or (meth)acrylamide monomers such as SR339NS, SR395, SR420, SR268, and SR259, manufactured by Sartomer, and Photomer 4184, manufactured by IGM.

[0069] Particularly preferably, component (B) may be present in an amount of 5% to 90% by weight, preferably 10% to 80% by weight, based on the total weight of the adhesive composition.

[0070] (C) Photoinitiator According to the present invention, the dual-cure adhesive composition includes (C) at least one photoinitiator, which can initiate and promote crosslinking of component (B) upon exposure to ultraviolet light. The use of a photoinitiator allows the composition of the present invention to cure rapidly, in less than one minute, preferably in a few tens of seconds, and more preferably in 1 to 10 seconds.

[0071] The photoinitiator used in the present invention is not particularly limited as long as it can promote free radical polymerization, crosslinking, or both. The photoinitiator and the amount thereof are preferably selected to achieve uniform reaction conversion as a function of thickness of the cured composition, and a total degree of conversion high enough to achieve the desired initial handling strength.

[0072] Useful photoinitiators include, for example, "alpha-cleavage" photoinitiators including benzil dimethyl ketal, benzoin ether, hydroxyalkyl phenyl ketone, benzoylcyclohexanol, dialkoxyacetophenone, 1-hydroxycyclohexyl phenyl ketone, trimethylbenzoylphosphine oxide, methylthiophenylmorpholinoketone, morpholinophenylaminoketone, and the like; hydrogen abstraction photoinitiators including photoinitiators and coinitiators based on benzophenone, thioxanthone, benzil, camphorquinone, and ketocoumarin; and combinations thereof.

[0073] Preferred photoradical polymerization initiators include, for example, acylphosphine oxides such as bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, bis(2,6-dimethoxybenzoyl)-(2,4,4-trimethylpentyl)-phosphine oxide, and 2,4,4-trimethylbenzoyldiphenylphosphine oxide.

[0074] These photoradical polymerization initiators can be used alone or in combination of two or more thereof.

[0075] Useful commercially available photoradical polymerization initiators are available under the following trade names: Omnirad 369 morpholinophenyl amino ketone, Omnirad 819 bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide and its preferred form CGI 819XF, Omnirad CGI 403 bis(2,6-dimethoxybenzoyl)-(2,4,4-trimethylpentyl)phosphine oxide, Omnirad 651 benzil dimethyl ketal, Omnirad 184 benzoylcyclohexanol, Omnirad 1173 hydroxyalkyl phenyl ketone, Omnirad 4265 a 50:50 blend of 2-hydroxy-2-methyl-1-phenylpropan-1-one and 2,4,6-trimethylbenzoyldiphenylphosphine oxide, and CGI 1700 a 25:75 blend of bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine and 2-hydroxy-2-methyl-1-phenylpropan-1-one; and Speedcure TPO-L, ethyl phenyl (2,4,6-trimethylbenzoyl)phosphinate, all available from IGM.

[0076] Generally, when a photoradical polymerization initiator is present in the composition, these compositions are cured at room temperature in less than 120 seconds, preferably less than 60 seconds, at wavelengths ranging from 200 nm to 410 nm, followed by the heat cure process described herein. As will be appreciated, the time and wavelength cure profile of each curable adhesive composition will vary, and different compositions can be designed to provide a cure profile suitable for a particular industrial manufacturing process.

[0077] Particularly preferably, when component (C) is present, its amount may be from 0.01% to 10%, preferably from 0.3% to 5%, by weight of the total composition.

[0078] (D) Moisture curing catalyst In accordance with the present invention, the dual-cure adhesive composition includes (D) at least one moisture-cure catalyst.

[0079] The moisture curing catalyst used in the present invention is not particularly limited as long as it can accelerate the moisture curing process. Useful catalysts here include compounds with ether and morpholine functional groups, such as 2,2'-dimorpholinoethyl ether, di(2,6-dimethylmorpholinoethyl)ether, and 4,4'-(oxydi-2,1-ethanediyl)bis-morpholine; metal catalysts include, but are not limited to, catalysts based on tin (e.g., dibutyltin dilaurate and dibutyltin acetate), bismuth, zinc, potassium, and combinations thereof.

[0080] Useful commercially available moisture cure catalysts are available under the trade names Jeffcat DMDEE, Catalyst CC, T9, BiCAT 8, and mixtures thereof.

[0081] Particularly preferably, the dual cure adhesive composition can be present in an amount of 0.01 wt % to 5 wt %, or even 0.05 wt % to 3 wt %, to promote moisture cure.

[0082] additives The dual cure adhesive composition may optionally include a variety of additives such as, for example, thermoplastic polymers, tackifiers, plasticizers, waxes, stabilizers, antioxidants, fillers, pigments, fluorescent agents, odor maskers, adhesion promoters (i.e., silane-based adhesion promoters), surfactants, defoamers, and combinations thereof.

[0083] Useful thermoplastic polymers include, for example, ethylene vinyl acetate, copolymers of ethylene vinyl acetate and vinyl alcohol, ethylene vinyl butyrate, ethylene acrylic acid, ethylene methacrylic acid, ethylene acrylamide copolymers, ethylene methacrylamide, acrylate copolymers (e.g., methyl acrylate, ethyl acrylate, methyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, methoxyethyl methacrylate, methoxyethyl acrylate, ethylene ethyl acrylate, ethylene n-butyl acrylate, ethylene hydroxyethyl acrylate), ethylene n-butyl acrylate carbon monoxide terpolymers, polyolefins (e.g., polypropylene, polyethylene), thermoplastic polyurethanes, butylene / poly(alkylene ether) phthalates, thermoplastic polyesters, and combinations thereof. The dual-cure adhesive composition optionally comprises from 0 to 4% by weight or less, or from 0.1 to 4% by weight or less, of the thermoplastic polymer.

[0084] Useful tackifiers include, for example, aromatic, aliphatic, and cycloaliphatic hydrocarbon resins, mixed aromatic and aliphatic modified resins, aromatic modified hydrocarbon resins, and their hydrogenated versions; terpenes, modified terpenes, and their hydrogenated versions; rosin esters (e.g., glycerol rosin ester, pentaerythritol rosin ester, and their hydrogenated versions); and combinations thereof. Useful aromatic resins include, for example, aromatic modified hydrocarbon resins, alpha-methylstyrene resins, styrene, polystyrene, cuminolone, indene, vinyltoluene, and styrenated terpene resins, polyphenols, polyterpenes, and combinations thereof. Useful aliphatic and cycloaliphatic petroleum hydrocarbon resins include, for example, branched and unbranched C5-C9 resins and their hydrogenated derivatives. Useful polyterpene resins include copolymers and terpolymers of natural terpenes (e.g., styrene-terpene, alpha-methylstyrene-terpene, and vinyltoluene-terpene).

[0085] Examples of useful antioxidants include hindered phenolic antioxidants, phosphite antioxidants, thioether antioxidants, etc. Commercially available examples include Omnirad 565, 1010, 1076, and Ernox 10 available from BASF. The dual-cure adhesive composition optionally contains up to 2 wt.% of an antioxidant.

[0086] An example of a useful stabilizer is 4-methylbenzenesulfonyl isocyanate, available as PTSI from Borchers.

[0087] Fillers can take a variety of forms, such as particles (spherical particles, beads, elongated particles), fibers, and combinations thereof. Examples of useful fillers include particulates including talc, clay, fumed silica and surface-treated versions thereof, carbon black, and mica, as well as microspheres selected from glass microspheres, polymeric microspheres, and combinations thereof. A commercially available example is RY300 manufactured by Evonik. The dual-cure adhesive composition optionally contains up to 5 wt. % of a filler.

[0088] Examples of useful pigments include inorganic pigments, organic pigments, reactive pigments, non-reactive pigments, and combinations thereof.

[0089] Suitable silane-based adhesion promoters include, for example, epoxyglycidoxypropyltrimethoxysilane, octyltriethoxysilane, methyltrimethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, methacryloxypropyltrimethoxysilane, alkyloxyiminosilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinylmethyldimethoxysilane, aminopropyltrimethoxysilane, aminopropyltriethoxysilane, N-phenylaminopropyltrimethoxysilane, bis-(trimethoxysilylpropyl)amine, N-β-(aminopropyltrimethoxysilane), Examples of suitable dual-cure adhesive compositions include N-beta-(aminoethyl)-aminopropyltrimethoxysilane, N-beta-(aminoethyl)-aminopropyltrimethoxysilane, N-beta-(aminoethyl)-aminopropyltrimethoxysilane, N-beta-(aminoethyl-aminopropyl-methyldimethoxysilane, ureidopropyltrimethoxysilane, tris[3-(trimethoxysilyl)propyl]isocyanurate, 4-amino-3,3-dimethylbutyldimethoxymethylsilane, and its ethoxy and methoxy / ethoxy versions, mercaptopropyltrimethoxysilane, and mixtures thereof. Commercially available examples include Silquest A-189 available from Momentive. The dual-cure adhesive composition optionally contains up to 2 wt. % of a silane adhesion promoter.

[0090] The total additives may comprise up to 15% by weight of the adhesive composition of the present invention, preferably up to 10% by weight.

[0091] adhesive composition In a particularly preferred embodiment, the dual cure adhesive composition comprises, based on the total weight of the adhesive composition: 5% to 90% by weight, preferably 10% to 80% by weight, of at least one isocyanate-terminated polyurethane prepolymer, 5% to 90% by weight, preferably 10% to 80% by weight, of at least one radically polymerizable compound, 0.01% to 10% by weight, preferably 0.3% to 5% by weight, of at least one photoinitiator, and 0.01% to 15% by weight, preferably 0.01% to 10% by weight of at least one additive.

[0092] Preparation method Dual cure adhesive compositions according to the present invention can be prepared by mixing all of the components according to the present invention until a homogeneous mixture is obtained.

[0093] The equipment used to perform the mixing, stirring, dispersion, etc. is not particularly limited. Examples of equipment that can be used include an automatic mortar equipped with a stirrer and a heating device, a Henschel mixer, a three-roll mill, a ball mill, a planetary mixer, and a bead mill. These equipment may also be used in combination as appropriate. The method for producing the dual-cure adhesive composition is not particularly limited, as long as the composition is a uniform mixture of the above components.

[0094] Laminate and electronic device According to a second aspect of the present invention, there is provided a laminate comprising a first substrate, a second substrate, and an adhesive layer disposed therebetween, wherein the first and second substrates are independently selected from glass, resin, and metal, preferably at least one of the two substrates is non-UV transparent, and the adhesive layer is formed by curing the adhesive composition of the present invention.

[0095] The first substrate and / or the second substrate can be composed of a single material and a single layer, or multiple layers of the same or different materials. The layers can be continuous or discontinuous.

[0096] The substrate of the articles described herein can have a variety of properties, including rigidity (e.g., a stiff substrate, i.e., the substrate cannot be bent using both hands, or the substrate breaks when an attempt is made to bend it using both hands), flexibility (e.g., a flexible substrate, i.e., the substrate can be bent with less than the strength of both hands), porosity, electrical conductivity, lack of electrical conductivity, and combinations thereof.

[0097] The substrate of the article can be in a variety of forms, such as, for example, a fiber, a thread, a yarn, a woven fabric, a nonwoven fabric, a film (e.g., a polymeric film, a metalized polymeric film, a continuous film, a discontinuous film, and combinations thereof), a foil (e.g., a metal foil), a sheet (e.g., a metal sheet, a polymeric sheet, a continuous sheet, a discontinuous sheet, and combinations thereof), and combinations thereof.

[0098] In a preferred embodiment, at least one of the substrates can be selected from non-UV-transparent materials such as metal fired paste, aluminum, tin, molybdenum, silver, conductive metal oxides such as indium tin oxide (ITO), fluorine-doped tin oxide, and aluminum-doped zinc oxide, glasses such as ink-glass and bare glass, and resins such as polycarbonate, polybutylene terephthalate, and polyamide. Further suitable metals include copper, gold, palladium, platinum, aluminum, indium, silver-plated copper, silver-plated aluminum, tin, and tin-plated copper. Preferably, the substrate is selected from any of the aforementioned materials.

[0099] The dual-cure adhesive composition of the present invention can be cured for 3 to 60 seconds with ultraviolet light having a wavelength of 200 to 410 nm, preferably 320 to 400 nm, and then further cured at room temperature in the range of 15°C to 35°C and a relative humidity of 50% for 1 to 7 days.

[0100] As will be appreciated, the time and temperature cure profile of each dual cure adhesive composition will vary, and different compositions can be designed to provide a cure profile suited to a particular industrial manufacturing process.

[0101] According to a third aspect of the present invention there is provided an electronic device comprising a laminate of the present invention or manufactured using an adhesive composition according to the present invention.

[0102] The dual-cure adhesive composition of the present invention can be applied to a substrate using any suitable application method, including automated fine line application, jet application, slot die coating, roll coating, gravure coating, transfer coating, pattern coating, screen printing, spray coating, filament coating, extrusion, air knife, trailing blade, brushing, dipping, doctor blade, offset gravure coating, gravure coating, and combinations thereof. The dual-cure adhesive composition can be applied as a continuous or discontinuous coating, in single or multiple layers, and combinations thereof.

[0103] use According to a fourth aspect of the present invention, there is provided the use of an adhesive composition according to the present invention or a laminate according to the present invention in the manufacture of an electronic device.

[0104] Suitable electronic devices include, but are not limited to, wearable electronic devices (e.g., watches and eyeglasses), handheld electronic devices (e.g., phones (e.g., cell phones and smartphones), cameras, tablets, e-readers, monitors (e.g., monitors used in hospitals, medical professionals, athletes, and individuals), watches, calculators, mice, touchpads, joysticks), computers (e.g., desktop computers and laptop computers), computer monitors, televisions, media players, or other electronic components. [Example]

[0105] example The following examples are intended to help those skilled in the art better understand and practice the present invention. The scope of the present invention is not limited by the examples, but is defined by the appended claims. Unless otherwise specified, all parts and percentages are by weight.

[0106] raw materials: PolyTHF TM 2000 is a polytetrahydrofuran polyol with a molecular weight (Mn) of 2000 g / mol available from BASF.

[0107] PolyTHF TM 1000 is a polytetrahydrofuran polyol with a molecular weight (Mn) of 1000 g / mol available from BASF.

[0108] PolyTHF TM 650S is a polytetrahydrofuran polyol with a molecular weight (Mn) of 650 g / mol available from BASF.

[0109] Voranol 2110 is a polyether polyol with a molecular weight (Mn) of 1000 g / mol available from Dow.

[0110] Desmodur TM 44C is monomeric diphenylmethane-4,4'-diisocyanate available from Covestro Polymers (China) Co., Ltd.

[0111] Evernox 10 is pentaerythritol tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] as an antioxidant, available from Everspring Chemical Company.

[0112] PTSI is 4-methylbenzenesulfonyl isocyanate as a stabilizer, available from Borchers.

[0113] CN8888NS is a polycarbonate-based urethane diacrylate oligomer available from Sartomer.

[0114] Photomer 4184 is a monofunctional 2-[[(butylamino)carbonyl]oxy]ethyl acrylate monomer available from IGM.

[0115] SR 339NS is a monofunctional phenoxyethyl acrylate monomer available from Sartomer.

[0116] SR 395 is a monofunctional isodecyl acrylate monomer available from Sartomer.

[0117] SR 420 is a monofunctional 3,3,5-trimethylcyclohexyl acrylate monomer available from Sartomer.

[0118] SR 268 is a tetraethylene glycol diacrylate monomer available from Sartomer.

[0119] SR 259 is an ethylene diacrylate monomer available from Sartomer.

[0120] Speedcure TPO-L is ethyl phenyl (2,4,6-trimethylbenzoyl) phosphinate, available from IGM.

[0121] Jeffcat DMDEE is 2,2-dimorpholinodiethyl ether, available from Huntsman.

[0122] Silquest A 189 is a silane-based adhesion promoter available from Momentive.

[0123] RY 300 is a fumed silica filler available from Evonik.

[0124] Preparation method: Preparation of Component (A) Isocyanate-Terminated Polyurethane Prepolymer: A reactor was charged with 78.68 g of PolyTHF™ 2000 and 0.47 g of Evernox 10. The mixture was stirred at 150°C for 2 hours under a 30 mbar vacuum to remove moisture. The mixture was then cooled to 110°C, and 20.85 g of Desmodur™ 44C was added. The mixture was stirred at 110°C for 10 minutes, then held at 120°C for 1 hour under a 30 mbar vacuum to obtain isocyanate-terminated polyurethane PU-09.

[0125] A reactor was charged with 9.33 g of Voranol 2110, 9.33 g of PolyTHF™ 1000, 55.95 g of PolyTHF™ 2000, and 0.47 g of Evernox 10. The mixture was stirred at 150°C for 2 hours under a 30 mbar vacuum to remove moisture. The mixture was then cooled to 110°C, and 24.45 g of Desmodur 44C was added. The mixture was stirred at 110°C for 10 minutes, then held at 120°C for 1 hour under a 30 mbar vacuum. 0.47 g of PTSI was added and the mixture was stirred at 120°C for 15 minutes to yield isocyanate-terminated polyurethane PU-43.

[0126] A reactor was charged with 9.09 g of PolyTHF™ 650S, 9.09 g of PolyTHF™ 1000, 54.47 g of PolyTHF™ 2000, and 0.47 g of Evernox 10. The mixture was stirred at 150°C for 2 hours under 30 mbar vacuum to remove moisture. The mixture was then cooled to 110°C, and 26.41 g of Desmodur 44C was added. The mixture was stirred at 110°C for 10 minutes, then held at 120°C for 1 hour under 30 mbar vacuum. 0.47 g of PTSI was added, and the mixture was stirred at 120°C for 15 minutes to yield isocyanate-terminated polyurethane PU-44.

[0127] Preparation of Dual Cure Adhesive Compositions of Examples and Comparative Examples: Comparative Example 1 (CEx.1) 5.0g of Photomer 4184, 25.0g of SR 420, 15.0g of SR 259, 0.5g of Silquest A 189, 2.0g of Speedcure TPO-L, and 49.5g of PU-09 were mixed in a planet mixer under a nitrogen atmosphere. 2.5g of RY 300 was then added to the mixer and stirred for 30 minutes. After mixing at 70°C, 0.5g of Jeffcat DMDEE was added to the mixer and degassed for 30 minutes to obtain the sample.

[0128] Comparative Example 2 (CEx.2) 5.0g of Photomer 4184, 10.0g of SR 420, 15.0g of SR 268, 0.5g of Silquest A 189, 2.0g of Speedcure TPO-L, 20.0g of CN8888NS, and 45.0g of PU-09 were mixed in a planet mixer under a nitrogen atmosphere. 2.0g of RY 300 was then added to the mixer and stirred for 30 minutes. After mixing at 70°C, 0.5g of Jeffcat DMDEE was added to the mixer and degassed for 30 minutes to obtain the sample.

[0129] Example 1 10.0g of SR 420, 20.0g of SR 339NS, 0.5g of Silquest A 189, 2.0g of Speedcure TPO-L, 15.0g of CN8888NS, and 51.0g of PU-43 were mixed in a Planet Mixer under a nitrogen atmosphere. 1.0g of RY 300 was then added to the mixer and stirred for 30 minutes. After mixing at 70°C, 0.5g of Jeffcat DMDEE was added to the mixer and degassed for 30 minutes to obtain a sample.

[0130] Example 2 10.0g of SR 420, 20.0g of SR 339NS, 0.5g of Silquest A 189, 2.0g of Speedcure TPO-L, 15.0g of CN8888NS, and 51.0g of PU-44 were mixed in a planet mixer under a nitrogen atmosphere. 1.0g of RY 300 was then added to the mixer and stirred for 30 minutes. After mixing at 70°C, 0.5g of Jeffcat DMDEE was added to the mixer and degassed for 30 minutes to obtain a sample.

[0131] Example 3 15.0g of SR 420, 25.0g of SR 395, 0.5g of Silquest A 189, 2.0g of Speedcure TPO-L, and 55.0g of PU-09 were mixed in a planet mixer under a nitrogen atmosphere, followed by 3g of RY 300 and stirring for 30 minutes. After mixing at 70°C, 0.5g of Jeffcat DMDEE was added to the mixer and degassed for 30 minutes to obtain a sample.

[0132] Example 4 15.0g of SR 420, 25.0g of Photomer 4184, 0.5g of Silquest A 189, 2.0g of Speedcure TPO-L, and 55.0g of PU-09 were mixed in a planet mixer under a nitrogen atmosphere, and 2.5g of RY 300 was added to the mixer and stirred for 30 minutes. After mixing at 70°C, 0.5g of Jeffcat DMDEE was added to the mixer and degassed for 30 minutes to obtain the sample.

[0133] Example 5 25.0g of SR 420, 10.0g of Photomer 4184, 0.5g of Silquest A 189, 2.0g of Speedcure TPO-L, and 60.0g of PU-09 were mixed in a planet mixer under a nitrogen atmosphere, followed by 3.0g of RY 300 and stirring for 30 minutes. After mixing at 70°C, 0.5g of Jeffcat DMDEE was added to the mixer and degassed for 30 minutes to obtain the sample.

[0134] Example 6 25.0g of SR 420, 15.0g of Photomer 4184, 0.5g of Silquest A 189, 2.0g of Speedcure TPO-L, and 55.0g of PU-09 were mixed in a planet mixer under a nitrogen atmosphere, followed by 3.0g of RY 300 and stirring for 30 minutes. After mixing at 70°C, 0.5g of Jeffcat DMDEE was added to the mixer and degassed for 30 minutes to obtain the sample.

[0135] Example 7 25.0g of SR 339NS, 15.0g of SR 395, 0.5g of Silquest A 189, 2.0g of Speedcure TPO-L, and 55.0g of PU-09 were mixed in a planet mixer under a nitrogen atmosphere, followed by 3g of RY 300 and stirring for 30 minutes. After mixing the mixture at 70°C, 0.5g of Jeffcat DMDEE was added to the mixer and degassed for 30 minutes to obtain a sample.

[0136] Test Method: Loss factor value tan δ The loss factor values ​​of each sample were measured using an Anton Paar modular compact rheometer MCR 302e in accordance with the dynamic oscillation test of ASTM D4440-15, where a sample of the adhesive composition was clamped with a plate clamp of 25 mm diameter and 1 mm thickness, and rheological measurements were carried out in oscillation mode at room temperature with a frequency of 10 rads and a strain of 0.01% or less for 60 seconds to allow stabilization, followed by rheological measurements using a LUMEN DYNAMICS OmniCure SERIES 1000 at a wavelength of 375 nm and an intensity of 50 mW / cm. 2 The sample was further irradiated with radiation for 60 seconds to obtain the storage modulus G' and loss modulus G'', and the loss factor value tanδ was calculated from the storage modulus G' and loss modulus G'' according to the following formula: tan δ=G'' / G'

[0137] The loss factor value, tan δ, can also be calculated automatically from the MCR 302e. As can be seen from Figure 1, the rheology curves for Example 1 (solid line) and Comparative Example 1 (dotted line) from 0 to 5 minutes were measured with the MCR 302e, and the loss factor values ​​at 120 seconds were 0.76 and 0.51, respectively (immediately after UV exposure ended). Each sample was tested, and the loss factor values ​​at 120 seconds were recorded in Table 1.

[0138] Compressibility after UV exposure The compression ratio of each sample after UV irradiation was evaluated by the following procedure: First, each sample was applied to an ink-coated glass sheet measuring (101.6 mm x 25.4 mm x 2 mm) and irradiated with UV light at a wavelength of 375 nm and an intensity of 150 mW / cm. 2 The sample was irradiated with an LED lamp for 20 seconds; the adhesive bead width was then observed under an optical microscope, measured accordingly, and recorded as the initial adhesive bead width after UV irradiation. A polycarbonate substrate was then laminated to the adhesive sample under a compression load of 2 kilograms for 15 seconds, and the adhesive bead width was observed and measured under an optical microscope and recorded as the adhesive bead width after compression. The compressibility of the adhesive composition sample after UV irradiation was calculated according to the following formula: JPEG2025541927000002.jpg24165

[0139] Samples with a high compression rate indicate that they are easy to compress and demonstrate their applicability for the intended purpose. Specifically, samples with a compression rate of 20% or higher were rated as "Good," samples with a compression rate of more than 0% but less than 20% were rated as "Good," and samples with a compression rate of 0% or lower were rated as "Poor."

[0140] Cross Tensile Strength Sample preparation: i. First, a polycarbonate substrate measuring 101.6 mm x 25.4 mm x 2 mm and an ink-glass substrate measuring 101.6 mm x 25.4 mm x 3 mm were prepared. The substrates were washed with isopropanol and left to idle at ambient conditions for several minutes to ensure the surfaces were completely dry. The first and second substrates were arranged in a cross shape, and an adhesive layer was formed between them where they overlapped.

[0141] ii. Next, to control the thickness of the adhesive layer, two spacers with a diameter of 0.1 mm were placed on the edge of the first substrate, 5 mm from the edge of the overlapping area, before the adhesive composition was dispersed.

[0142] iii. The adhesive composition was then dispensed at room temperature using a Loctite 400D dispenser. A 19# needle was used to apply the adhesive composition to the surface of the ink-glass. During the dispensing process, two adhesive lines were formed by adhesive beads dispensed through the needle. The two adhesive lines were applied parallel to each other, each 5.0 mm from the edge of the overlapping area of ​​the two substrates. Furthermore, the distance between each adhesive bead was controlled to 15.4 mm.

[0143] iv. After dispensing, the adhesive beads were illuminated with a 375nm LED lamp at an intensity of 150mw / cm 2 The laminate was then cured by irradiating at 400 K for 20 seconds. The polycarbonate substrates were pressed against the bead line to form a sandwich structure of overlapping portions, while the ends of each substrate were left free. Next, the laminate was prepared.

[0144] v. A 2 kilogram weight was applied to the overlapping sandwich structure for 15 seconds, after which the weight was removed and the resulting sample was left at 23°C and 50% relative humidity for 24 hours to allow the adhesive composition to cure.

[0145] Sample test: To measure the tensile strength at break of the adhesive layer, the cross tensile strength of the sample was measured using an Instron tensile tester at a test speed of 10 mm / min. The load at break was recorded accordingly. The adhesive composition was considered acceptable if the tensile strength was 75 N or more, preferably 100 N or more.

[0146] [Table 1]

[0147] As can be seen from Table 1, dual-cure adhesive compositions with loss factor values ​​greater than 0.6 at 120 seconds exhibit significant compressibility and excellent cross tensile strength upon cure, compared to comparative examples with loss factor values ​​outside the claimed range.

[0148] While several preferred embodiments have been described, many modifications and variations are possible in light of the above teachings. It is therefore understood that the invention can be practiced otherwise than as specifically described without departing from the scope of the appended claims.

Claims

1. (A) at least one isocyanate-terminated polyurethane prepolymer; (B) at least one radically polymerizable compound; (C) at least one photoinitiator, and (D) at least one moisture-cure catalyst; A dual cure adhesive composition comprising: Wavelength 375nm, intensity 50mW / cm ２ 1. A dual-cure adhesive composition, wherein the composition after 60 seconds of exposure to ultraviolet light has a loss factor of greater than 0.6 as measured at room temperature according to ASTM D4440-15.

2. 10. The dual-cure adhesive composition of claim 1, wherein component (A) is the reaction product of a reaction mixture comprising at least one polyether polyol and at least one polyisocyanate having at least two isocyanate groups per molecule.

3. The dual cure adhesive composition of claim 2 wherein the polyether polyol is polyhydrofuran.

4. The dual-cure adhesive composition of claim 2 , wherein the reaction mixture further comprises at least one amorphous polyester polyol and / or polycarbonate polyol.

5. The reaction mixture may contain, based on the total weight of the reaction mixture: 10 to 85 wt. %, preferably 20 to 80 wt. %, of a polyether polyol; 0 to 30 wt. %, preferably 0 to 20 wt. %, of an amorphous polyester polyol; 0 to 30 wt. %, preferably 0 to 20 wt. %, of a polycarbonate polyol, and 15 to 90% by weight, preferably 20 to 80% by weight, of a polyisocyanate having at least two isocyanate groups in one molecule; 3. The dual cure adhesive composition of claim 2, comprising:

6. 10. The dual-cure adhesive composition of claim 1, wherein component (B) is selected from (meth)acrylate monomers, (meth)acrylamide monomers, (meth)acrylate oligomers, (meth)acrylamide oligomers, (meth)acrylate polymers, (meth)acrylamide polymers, and combinations thereof, preferably selected from monofunctional (meth)acrylate monomers, monofunctional (meth)acrylamide monomers, monofunctional urethane (meth)acrylate oligomers, difunctional urethane (meth)acrylate oligomers, and combinations thereof.

7. 10. The dual-cure adhesive composition of claim 1, wherein component (C) is selected from benzil dimethyl ketal, benzoin ether, hydroxyalkyl phenyl ketone, benzoylcyclohexanol, dialkoxyacetophenone, 1-hydroxycyclohexyl phenyl ketone, trimethylbenzoylphosphine oxide, methylthiophenyl morpholinoketone, morpholinophenyl aminoketone, benzophenone, thioxanthone, benzil, camphorquinone, ketocoumarin, and combinations thereof.

8. 10. The dual-cure adhesive composition of claim 1, wherein component (D) is selected from compounds having ether and morpholine functional groups, metal catalysts based on tin, bismuth, zinc, and potassium, and combinations thereof, preferably 2,2′-dimorpholinoethyl ether, di(2,6-dimethylmorpholinoethyl)ether, 4,4′-(oxydi-2,1-ethanediyl)bis-morpholine, dibutyltin dilaurate, and dibutyltin acetate, and combinations thereof.

9. 10. The dual-cure adhesive composition of claim 1, further comprising at least one additive selected from thermoplastic polymers, tackifiers, plasticizers, waxes, stabilizers, antioxidants, fillers, pigments, fluorescent agents, odor maskers, adhesion promoters, surfactants, defoamers, and combinations thereof.

10. 10. The dual-cure adhesive composition of claim 1, wherein component (A) is present in an amount of 5 to 90 weight percent, preferably 10 to 80 weight percent, of the total weight of the composition.

11. 10. The dual-cure adhesive composition of claim 1, wherein component (B) is present in an amount of 5 to 90 weight percent, preferably 10 to 80 weight percent, of the total weight of the composition.

12. 10. The dual-cure adhesive composition of claim 1, wherein component (C) is present in an amount of 0.01 to 10 weight percent, preferably 0.3 to 5 weight percent, of the total weight of the composition.

13. 10. The dual-cure adhesive composition of claim 1, wherein component (D) is present in an amount of 0.01 to 5 weight percent, preferably 0.05 to 3 weight percent, of the total weight of the composition.

14. A laminate comprising a first substrate, a second substrate, and an adhesive layer sandwiched therebetween, wherein the first and second substrates are independently selected from glass, resin, and metal, and preferably at least one of the two substrates is non-ultraviolet transparent, and the adhesive layer is formed by curing the adhesive composition according to any one of claims 1 to 13.

15. An electronic device comprising the laminate of claim 14.

16. Use of the adhesive composition according to any one of claims 1 to 13 in the manufacture of an electronic device.

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