KR102339285B1 - Adhesive composition and method of temporarily fixing member using the same - Google Patents

Abstract

A photocurable adhesive composition is disclosed. The disclosed photocurable adhesive composition has at least one (meth)acrylate group at the terminal of the molecule, and includes an oligomer having a molecular weight of 1,000 to 9,000; a polyfunctional first acrylate compound having two or more (meth)acrylate groups and a hydrophilic group including at least one of a hydroxyl group (-OH) and a carboxyl group (-COOH); The oligomer and the first acrylate compound are different from each other, and a monofunctional second acrylate compound; photoinitiator; and a polymer bead comprising at least one compound of polymethyl methacrylate (PMMA) and polystyrene (PS), and has no glass transition temperature after curing under curing conditions of ^{80 mW and 1 J/cm 2 , 80 mW and} After curing under curing conditions of 6J/cm ² , the weight reduction rate is 1.0 or more when immersed in hot water at 90° C. for 10 minutes.

Description

Photocurable adhesive composition and method of temporarily fixing member using the same {Adhesive composition and method of temporarily fixing member using the same}

A photocurable adhesive composition and a method for temporarily fixing a member using the same are disclosed. More specifically, a photocurable adhesive composition comprising an acrylate compound having a hydrophilic group and a method for temporarily fixing a member using the same are disclosed.

As an adhesive for temporarily fixing optical lenses, prisms, arrays, silicon wafers, semiconductor mounting parts, etc., a hot melt adhesive (eg, a wax adhesive) is used, and a member bonded or laminated with such a hot melt adhesive is formed in a predetermined shape. After cutting with an adhesive, a method of manufacturing a processing member by removing the adhesive is being performed.

However, the hot melt adhesive is disadvantageous in terms of processability control because it is not easy to control the flow characteristics due to the change in viscosity during heating. It is also disadvantageous in terms of time reduction, and since the member has to be washed several times after dissolving the adhesive by immersing the member in an organic solvent or the like after processing is completed, the peeling and cleaning process is complicated.

In order to solve these problems, a photocurable adhesive is used as an adhesive for temporarily fixing. Since the photocurable adhesive is a liquid under a light-shielded environment, it is not necessary to heat-melt it and process it into a liquid like a hot-melt adhesive, but also has excellent applicability. In addition, after laminating a plurality of members, the laminated members may be impregnated with an adhesive, and the adhesive after impregnation can be instantaneously cured by irradiation with light, so that workability is excellent.

[Prior art literature]

[Patent Literature]

(Patent Document 1) Japanese Patent Laid-Open No. 2-88604

One embodiment of the present invention provides a photocurable adhesive composition comprising an acrylate compound having a hydrophilic group.

Another embodiment of the present invention provides a method of temporarily fixing a member using the photocurable adhesive composition.

One aspect of the present invention is

an oligomer having one or more (meth)acrylate groups at the end of the molecule and having a molecular weight of 1,000 to 9,000;

a polyfunctional first acrylate compound having two or more (meth)acrylate groups and a hydrophilic group including at least one of a hydroxyl group (-OH) and a carboxyl group (-COOH);

The oligomer and the first acrylate compound are different from each other, and a monofunctional second acrylate compound;

photoinitiator; and

A polymer bead comprising at least one compound of polymethyl methacrylate (PMMA) and polystyrene (PS),

It does not have a glass transition temperature after curing under the curing conditions of 80mW and 1J/cm ^{2 ,}

After curing under curing conditions of 80mW and 6J/cm ² , it provides a satisfactory photocurable adhesive composition having a weight reduction ratio of 1.0 or more when immersed in hot water at 90° C. for 10 minutes.

The photocurable adhesive composition is based on 100 parts by weight of the total content of the oligomer, the first acrylate compound, and the second acrylate compound, 30 to 70 parts by weight of the oligomer, 10 to 35 parts by weight of the first acrylate compound parts, and 20 to 35 parts by weight of the second acrylate compound, 5 to 15 parts by weight of the photopolymerization initiator, and 1 to 5 parts by weight of the polymer beads.

The polymer beads may not be foamed during UV curing.

The polymer beads may not include acrylonitrile-based beads.

Another aspect of the present invention is

It provides an adhesive comprising the photocurable adhesive composition.

Another aspect of the present invention is

forming a first laminate by bonding a plurality of members using the photocurable adhesive composition;

forming a second laminate including a primary cured product by primary curing the photocurable adhesive composition in the laminate;

forming a third laminate by processing the second laminate;

further curing the primary cured product in the third laminate to form a fourth laminate including the secondary cured product; and

It provides a method of temporarily fixing the member comprising the step of immersing the fourth laminate in water to remove the secondary cured product in the fourth laminate.

When the photocurable adhesive composition according to an embodiment of the present invention is used for temporarily fixing a member, it has excellent processability, it is possible to shorten the process time, and spontaneous peeling can be improved.

1 is a storage elastic modulus (storage modulus) changes, the loss elastic modulus (loss modulus) changes, and tangent delta (Tan of the photo-cured product of a curing adhesive composition (@ 80mW and curing conditions of 2J / cm ²⁾ prepared in Example 3 ( delta)) is a graph showing the change according to temperature.

Hereinafter, a photocurable adhesive composition according to an embodiment of the present invention will be described in detail.

In the present specification, "substituting a hydrophilic group of material A" means a material obtained by substituting a hydrophilic group for a hydrogen atom in material A.

In addition, in the present specification, "spontaneous peeling" refers to a fully cured product of the photocurable adhesive composition ( ^{UV-cured under curing conditions of 80mW and 6J/cm 2} ) is immersed in a temperature of 90° C., within a time of less than 10 minutes. It means peeling in the form of a film.

The photocurable adhesive composition according to an embodiment of the present invention includes an oligomer, a first acrylate compound, a second acrylate compound, a photopolymerization initiator, and polymer beads.

The oligomer, the first acrylate compound, and the second acrylate compound may be different from each other (eg, different chemical formulas).

After the photocurable adhesive composition is cured ( ^{UV cured under curing conditions of 80mW and 6J/cm 2} ), the weight reduction rate when immersed in hot water at 90° C. for 10 minutes may satisfy the following Equation 1:

[Equation 1]

Weight loss rate (%) = (Wi-Wf)/Wi * 100 ≥ 1.0

where Wi is the initial weight of the cured product of the photocurable adhesive composition, and Wf is the weight after immersing the cured product of the photocurable adhesive composition having an initial weight of Wi in hot water at 90° C. for 10 minutes and then taking it out and drying it

When the weight reduction ratio is 1.0% or more, the cured product of the photocurable adhesive composition may be spontaneously peeled off.

Coefficient of thermal expansion (Resin CTE) of the acrylate resin, which is a cured product of the oligomer, the first acrylate compound, the second acrylate compound, and the photopolymerization initiator ( ^{UV-cured under curing conditions of 80mW and 6J/cm 2 )} And the coefficient of thermal expansion (Bead CTE) of the polymer bead may satisfy the following Equation 2:

[Equation 2]

When the ratio (Bead CTE/Resin CTE) is less than 0.2, the cured product of the photocurable adhesive composition may be spontaneously peeled off.

The oligomer has one or more (meth)acrylate groups at the end of the molecule, and may have a molecular weight of 1,000 to 9,000.

For example, the oligomer is urethane (meth) acrylate, 1,2-polybutadiene-terminated urethane (meth) acrylate, 1,4-polybutadiene-terminated urethane (meth) acrylate, polyisoprene-terminated (meth) acrylate , polyester urethane (meth) acrylate, polyether urethane (meth) acrylate, polyester (meth) acrylate, bis A-type epoxy (meth) acrylate, their respective hydrophilic group substitutions, each of these hydrogens additives or combinations thereof.

The urethane (meth)acrylate may be prepared by reacting polyisocyanate, polyol, and (meth)acrylic acid.

The polyisocyanate is 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, m-phenylene diisocyanate, xylylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate. , lysine diisocyanate ester, 1,4-cyclohexylene diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, 3,3'-dimethyl-4,4'-biphenylene diisocyanate, or a combination thereof can do.

The polyol may include polyesterdiol, polyetherdiol, polycaprolactonediol, polycarbonate diol, or a combination thereof.

The content of the oligomer may be 30 to 70 parts by weight based on 100 parts by weight of the total content of the oligomer, the first acrylate compound, and the second acrylate compound. When the content of the oligomer is within the above range, the cured product of the photocurable adhesive composition may be peeled off in the form of a film, and workability may be improved by increasing the viscosity.

The first acrylate compound may have a hydrophilic group including at least one of a hydroxyl group (-OH) and a carboxyl group (-COOH). As such, when the first acrylate compound includes a hydrophilic group, when the photocurable adhesive composition is used for temporarily fixing a member, spontaneous peeling can be promoted.

In addition, the first acrylate compound may have two or more (meth)acrylate groups. For example, the first acrylate compound may include a polyfunctional (meth)acrylate. For example, the first acrylate compound may include a difunctional (meth)acrylate, a trifunctional (meth)acrylate, a tetrafunctional or more (meth)acrylate, or a combination thereof.

The bifunctional (meth)acrylate is 1,3-butylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexadiol di(meth)acrylate, 1 , 9-nonanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, dicyclopentanyl di (meth) acrylate, 2-ethyl-2-butyl-propanediol (meth) acrylate, neopentyl Glycol-modified trimethylolpropane di(meth)acrylate, stearic acid-modified pentaerythritol diacrylate, polypropylene glycol di(meth)acrylate, 2,2-bis(4-(meth)acryloxydiethoxyphenyl)propane , 2,2-bis(4-(meth)acryloxypropoxyphenyl)propane, 2,2-bis(4-(meth)acryloxytetraethoxyphenyl)propane, each hydrophilic group substituted or a combination thereof may include

The trifunctional (meth)acrylate may include trimethylolpropane tri(meth)acrylate, tris[(meth)acryloxyethyl]isocyanurate, a hydrophilic group substituted for each of these, or a combination thereof.

The tetrafunctional or higher (meth)acrylate is dimethylolpropanetetra(meth)acrylate, pentaerythritol tetra(meth)acrylate, pentaerythritol ethoxytetra(meth)acrylate, dipentaerythritol penta (meth)acrylate, dipentaerythritol hexa(meth)acrylate, each of these may include a hydrophilic group substitution, or a combination thereof.

The content of the first acrylate compound may be 10 to 35 parts by weight based on 100 parts by weight of the total amount of the oligomer, the first acrylate compound, and the second acrylate compound. When the content of the first acrylate compound is within the above range, there is no fear that the initial adhesiveness of the photocurable adhesive composition may be lowered, and the cured product may be peeled off in the form of a film.

The second acrylate compound may include a monofunctional (meth)acrylate.

The monofunctional (meth) acrylate is methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isooctyl ( Meth) acrylate, isodecyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, phenyl (meth) acrylate, cyclohexyl (meth) acrylate, dicyclopentanyl (meth) Acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, isobornyl (meth) acrylate, methoxylated cyclodecatriene (meth) acrylate, 2-hydroxy Ethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, glycidyl (meth) acrylate, caprolactone-modified tetrahydrofurfuryl (meth) acrylate, 3-chloro-2-hydroxypropyl (meth) Acrylate, N,N-dimethylaminoethyl (meth)acrylate, N,N-diethylaminoethyl (meth)acrylate, t-butylaminoethyl (meth)acrylate, ethoxycarbonylmethyl (meth)acryl Rate, phenol ethylene oxide modified acrylate, phenol (2 moles of ethylene oxide modified) acrylate, phenol (4 moles of ethylene oxide modified) acrylate, paracumylphenol ethylene oxide modified acrylate, nonylphenol ethylene oxide modified acrylate, nonylphenol (Ethylene oxide modified by 4 moles) acrylate, nonylphenol (modified by 8 moles of ethylene oxide) acrylate, nonylphenol (modified by 2.5 moles of propylene oxide) acrylate, 2-ethylhexyl carbitol acrylate, ethylene oxide modified phthalic acid (meth ) acrylate, ethylene oxide-modified succinic acid (meth) acrylate, trifluoroethyl (meth) acrylate, acrylic acid, methacrylic acid, maleic acid, fumaric acid, ω-carboxy-polycaprolactone mono (meth) acrylate , Monohydroxyethyl phthalate (meth) acrylate, (meth) acrylic acid dimer, β- (meth) acroyloxyethyl hydrogen succinate, n- (meth) to) acryloyloxyalkylhexahydrophthalimide, each of these hydrophilic group substitutions, or a combination thereof.

The content of the second acrylate compound may be 20 to 35 parts by weight based on 100 parts by weight of the total amount of the oligomer, the first acrylate compound, and the second acrylate compound. When the content of the second acrylate compound is within the above range, there is no fear that the initial adhesiveness of the photocurable adhesive composition is lowered, and the cured product may be peeled off in the form of a film.

The photoinitiator serves to promote photocuring of the photocurable adhesive composition.

For example, the photoinitiator is benzophenone or a derivative thereof, benzyl or a derivative thereof, anthraquinone or a derivative thereof, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, benzoin isobutyl ether, benzyl Benzoin derivatives such as dimethyl ketal, acetophenone derivatives such as diethoxyacetophenone and 4-t-butyltrichloroacetophenone, 2-dimethylaminoethylbenzoate, p-dimethylaminoethylbenzoate, diphenyldisulfide, thi Oxanthone and its derivatives, camphorquinone, 7,7-dimethyl-2,3-dioxobicyclo[2.2.1]heptane-1-carboxylic acid, 7,7-dimethyl-2,3-dioxobicyclo[2.2 .1]heptane-1-carboxy-2-bromoethyl ester, 7,7-dimethyl-2,3-dioxobicyclo[2.2.1]heptane-1-carboxy-2-methylester, 7,7-dimethyl camphorquinone derivatives such as -2,3-dioxobicyclo[2.2.1]heptane-1-carboxylic acid chloride; 2-Methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone- α-aminoalkylphenone derivatives such as 1, benzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, benzoyldiethoxyphosphine oxide, 2,4,6-trimethylbenzoyldimethoxyphenylphosphine acylphosphine oxide derivatives such as fin oxide and 2,4,6-trimethylbenzoyl diethoxyphenylphosphine oxide; or a combination thereof.

The content of the photoinitiator may be 5 to 15 parts by weight based on 100 parts by weight of the total amount of the oligomer, the first acrylate compound, and the second acrylate compound. When the content of the photoinitiator is within the above range, not only curing of the photocurable adhesive composition is promoted, but also the degree of crosslinking of the cured product is increased, so that positional misalignment during cutting does not occur, and peelability can be improved.

The polymer beads may not be foamed during UV curing.

In addition, the polymer beads may be foamed when in contact with water (eg, hot water of 90° C. or less).

In addition, the polymer beads may include beads including at least one compound of polymethyl methacrylate (PMMA) and polystyrene (PS), but may not include acrylonitrile-based beads.

The content of the polymer beads may be 1 to 5 parts by weight based on 100 parts by weight of the total content of the oligomer, the first acrylate compound, and the second acrylate compound. When the content of the polymer beads is within the above range, spontaneous peeling of the cured product of the photocurable adhesive composition is possible. In particular, when the content of the polymer beads exceeds 5 parts by weight based on 100 parts by weight of the total content of the oligomer, the first acrylate compound and the second acrylate compound, agglomeration of the polymer beads in the photocurable adhesive composition A phenomenon may occur and photocuring may be inhibited, thereby inhibiting spontaneous peeling.

The photocurable adhesive composition, if necessary, methylhydroquinone, hydroquinone, 2,2-methylene-bis(4-methyl-6-tertbutylphenol), catechol, hydro-8-quinone monomethyl ether, mono -tertbutylhydroquinone, 2,5-di-tertbutylhydroquinone, p-benzoquinone, 2,5-diphenyl-p-benzoquinone, 2,5-di-tertbutyl-p-benzoquinone, picric acid, polymerization inhibitors such as citric acid, phenothiazine, tertbutylcatechol, 2-butyl-4-hydroxyanisole and 2,6-di-tertbutyl-p-cresol; various elastomers such as acrylic rubber, urethane rubber, and acrylonitrile-butadiene-styrene rubber; inorganic fillers; solvent; extender; reinforcement; plasticizer; thickener; dyes; pigment; flame retardant; silane coupling agent; surfactants or combinations thereof.

In addition, the photocurable adhesive composition is characterized in that it does not have a glass transition temperature after curing under curing conditions ^{of 80mW and 1J/cm 2 .} Specifically, the photocurable adhesive composition does not have a Tg (glass transition temperature) because it forms a thermoset structure (thermosetting structure) after curing under curing conditions of 80 mW and 1 J/cm ^{2 .} These properties can make glass workability better than when it has Tg. The thermoset structure is presumed to be a phenomenon that occurs due to high compatibility between the oligomer and the monomers (ie, the first acrylate compound and the second acrylate compound).

Another embodiment of the present invention provides an adhesive comprising the photocurable adhesive composition or a cured product thereof.

Another embodiment of the present invention comprises the steps of bonding a plurality of members using the photocurable adhesive composition to form a first laminate (S10), primary curing of the photocurable adhesive composition in the laminate (for example, For example, curing under curing conditions of 80 mW and 1 J/cm ² ) to form a second laminate including the primary cured product (S20), processing the second laminate to form a third laminate (S30), further curing the primary cured product in the third laminate (for example, ^{curing under curing conditions of 80 mW and 6J/cm 2} ) to form a fourth laminate including the secondary cured product It provides a method of temporarily fixing a member comprising the step (S40), and the step (S50) of immersing the fourth laminate in water to remove the secondary cured product in the fourth laminate.

In the step (S10), the member may have UV transmittance.

For example, the member may include a quartz member, a glass member (eg, ultra thin glass), or a plastic member. Specifically, the member may include a crystal vibrator, a glass lens, a plastic lens, an optical disk, or a combination thereof.

Also, in the step (S10), in the first laminate, an appropriate amount of an adhesive (or photocurable adhesive composition) is applied to the adhesive surface of the member to be fixed, and then another member is placed on the member and then the adhesive is applied thereon It may be manufactured by repeating the process, or it may be manufactured by laminating a plurality of members to be temporarily fixed in advance and then applying an adhesive (or photocurable adhesive composition) by penetrating between the members.

The step (S20) may be performed by irradiating visible light or ultraviolet light to the first laminate. By the step (S20), the members in the first laminate may be temporarily fixed by the primary cured product. The primary cured product may include a partially cured product (eg, semi-cured material) of the photocurable adhesive composition.

The processing in step S30 may be cutting, grinding, grinding, and/or punching the member into a desired shape.

The step S40 may be performed by irradiating visible light or ultraviolet light to the third laminate. In step S40 , the secondary cured product in the fourth laminate may have improved peelability compared to the primary cured product in the third laminate. That is, the step S40 is a step for improving the peelability of the adhesive to the members. The secondary cured product may include a fully cured product of the photocurable adhesive composition.

The step (S50) may be performed by immersing the fourth laminate in water at a temperature of 90° C. or less (eg, 30-80° C. or 40-80° C.). In addition, in the step (S50), the secondary cured product swells within a short time to release the residual strain stress, so that the adhesive strength to the member is lowered, so that the secondary cured product can be removed from the member in a film form within a short time. In addition, it is recommended because the method of immersing the entire fourth laminate in hot water in the step (S50) is simple.

Temporarily fixing method of a member according to an embodiment of the present invention having the configuration as described above can process various members such as optical members with high processing precision without using an organic solvent.

In addition, in the temporary fixing method of the member, when the secondary cured product is removed after processing is completed, the secondary cured product is swollen in contact with hot water of 90° C. or less, so that it can be removed from the member in a film form within a short time, so that the workability is improved. It has excellent advantages.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

Examples 1 to 10 and Comparative Examples 1 to 15: Preparation of photocurable adhesive composition

A photocurable adhesive composition was prepared by mixing the oligomer (R1), the first acrylate compound (R2), the second acrylate compound (R3), the photopolymerization initiator (PI), and the polymer beads (PB). The types and contents of each component are summarized and shown in Table 1 below.

R1 R2 R3 PI PB R11 R12 R13 R21 R22 R31 R32 PB1 PB2 Example 1 0 30 0 0 35 35 0 10 0 3 Example 2 0 70 0 0 10 20 0 10 0 3 Example 3 0 50 0 0 20 30 0 10 0 3 Example 4 0 50 0 0 20 30 0 5 0 3 Example 5 0 50 0 0 20 30 0 15 0 3 Example 6 0 50 0 0 20 30 0 10 0 One Example 7 0 50 0 0 20 30 0 10 0 5 Example 8 50 0 0 0 20 30 0 10 0 3 Example 9 0 50 0 20 0 30 0 10 0 3 Example 10 0 50 0 0 20 0 30 10 0 3 Comparative Example 1 0 50 0 0 20 30 0 10 3 0 Comparative Example 2 0 25 0 0 40 35 0 10 0 3 Comparative Example 3 0 75 0 0 5 20 0 10 0 3 Comparative Example 4 0 25 0 0 35 40 0 10 0 3 Comparative Example 5 0 75 0 0 10 15 0 10 0 3 Comparative Example 6 0 50 0 0 35 15 0 10 0 3 Comparative Example 7 0 50 0 0 10 40 0 10 0 3 Comparative Example 8 0 50 0 0 20 30 0 0 0 3 Comparative Example 9 0 50 0 0 20 30 0 3 0 3 Comparative Example 10 0 50 0 0 20 30 0 20 0 3 Comparative Example 11 0 50 0 0 20 30 0 10 0 0 Comparative Example 12 0 50 0 0 20 30 0 10 0 0.5 Comparative Example 13 0 50 0 0 20 30 0 10 0 7 Comparative Example 14 0 0 50 0 15 35 0 10 0 3 Comparative Example 15 0 0 30 0 15 55 0 10 0 3

- R11 (BR-541S): Manufacturer (DYMAX), brand name (BOMAR?? BR-541S), compound name (polyether urethane acrylate oligomer), molecular weight (3,000), no hydrophilic group.

- R12 (BR-202): Manufacturer (DYMAX), brand name (BOMAR?? BR-202), compound name (aromatic polyether urethane dimethacrylate), molecular weight (5,000), no hydrophilic group.

- R13 (UV-3000B): Manufacturer (Mitsubishi Chemical), trade name (SHIKOH?? UV-3000B), compound name (aliphatic urethane acrylate oligomer), molecular weight (18000), no hydrophilic group.

- R21 (M500): Manufacturer (Miwon Specialty), brand name (M500), compound name (Dipentaerythritol Pentaacrylate), molecular weight (578), including hydrophilic group (-OH).

- R22 (M340): Manufacturer (Miwon Specialty), brand name (M340), compound name (Pentaerythritol Triacrylate), molecular weight (298), including hydrophilic group (-OH).

- R31 (M170): Manufacturer (Miwon Specialty), brand name (M170), compound name (Ethoxy ethoxy ethyl Acrylate), molecular weight (188), no hydrophilic group.

- R32 (M121): Manufacturer (Miwon Specialty), brand name (M121), compound name (Lauryl Methacrylate), molecular weight (254), no hydrophilic group.

- PI (Irgacure 651): Manufacturer (BASF), trade name (Irgacure 651), compound name (2,2-dimethoxy-2-phenyl acetophenone)

- PB1 (F-36D): manufacturer (Asahi Kasei Corporation), trade name (F-36D), thermally expandable microcapsule

- PB2 (MH40FD): Manufacturer (Kolon Industries), trade name (MH-40FD), PMMA Polymer Bead

evaluation example

Viscosity, adhesion, die shear strength (DSS), storage modulus, glass transition temperature, glass workability, weight reduction rate, peeling time, peeling of each photocurable adhesive composition prepared in Examples 1 to 10 and Comparative Examples 1 to 15 The status and commercialization potential were evaluated in the following manner, and the results are shown in Table 2 below.

In addition, the CTE (coefficient of thermal expansion) of each of the resin and polymer beads in the photocurable adhesive compositions prepared in Examples 1 to 10 and Comparative Examples 1 to 15 was evaluated in the following manner, and the results are shown in Table 2 below shown in Here, "resin" means a fully cured product of the first acrylate compound, the first acrylate compound, the second acrylate compound, and the photopolymerization initiator (except for polymer beads). In addition, the CTE ratio was calculated according to Equation 1' below, and the results are shown in Table 2 below.

[Equation 1']

CTE ratio = CTE of polymer beads/CTE of resin

<Viscosity Measurement>

According to the method of ASTM D 2196, a value was measured after 1 minute had elapsed after loading each of the photocurable adhesive compositions into the viscometer using a Brookfield DV-II+ Pro viscometer (#62 spindle, 100rpm).

<DSS Measurement>

Sample 1 was obtained by first UV curing each of the photocurable adhesive compositions ^{under curing conditions of 80 mW and 1J/cm 2 .} Subsequently, the sample 1 cured secondary UV cure in terms of 80mW and 6J / cm ² to obtain a sample 2. Thereafter, for each of Sample 1 and Sample 2, DSS was measured using a Dage4000 device by the method of MIL-STD-883E.

<Measurement of storage modulus>

The front side between the release film with the optical path of each of the coating and curing conditions, and 80mW and 2J / cm ² for curing adhesive composition in a thickness of 0.6mm so that air bubbles does not occur, the back of the UV curing and the curing conditions of 80mW and 2J / cm ² Samples were prepared by UV curing. The sample was cut to a length of 50 mm and a width of 5 mm, and the storage modulus for each temperature was measured. The storage modulus measured at 1 Hz and 25° C. is recorded in Table 2 below.

In addition, the change in storage modulus according to the temperature of the cured product of the photocurable adhesive composition prepared in Example 3 ( ^{curing conditions of @ 80mW and 2J/cm 2 ) was measured by the loss modulus change and tangent delta (} Tan (delta)) is shown in Figure 1 together with the change. Although not shown in the drawings, the cured products of the photocurable adhesive compositions prepared in Examples 1 to 2 and 4 to 10 ( ^{curing conditions of @ 80mW and 2J/cm 2} ) also have a storage modulus according to temperature in a pattern similar to that of FIG. 1 . , the loss modulus and tangent delta changes are shown.

* Measuring instruments and measuring conditions

① Measuring instrument: DMA 850, TA Instruments Inc.

② Force: 0.01N

③ Measurement temperature range: -50~150℃

④ Temperature sweep: 2℃/min

⑤ Measurement frequency: 1Hz

<Measurement of glass transition temperature (Tg)>

When measuring the storage modulus of each photocurable adhesive composition, the temperature of the region having the highest tan delta was confirmed, and this was recorded as the glass transition temperature (Tg). However, when it was impossible to measure the glass temperature, it was indicated as "no glass transition temperature" (simply, "none"). Referring to FIG. 1 with respect to the glass transition temperature, it was found that there is no characteristic peak in the tangent delta change curve according to the temperature, which means that the measurement of the glass temperature is impossible.

<Evaluation of Glass Machinability>

Each composition was coated on glass (100mmХ150mmХthickness 1mm) to a thickness of 70㎛, and then UV cured under ^{80mW and 1J/cm 2 conditions to prepare a sample.} When silicone carbide paper #220 was applied to the side of this sample and polished at 400rpm, if glass floatation, UV resin particles, or residues occurred, it was evaluated as “bad”, otherwise, it was evaluated as “good”.

<CTE measurement>

First, the first acrylate compound, the first acrylate compound, the second acrylate compound, and the photopolymerization initiator (except polymer beads) in each of the photocurable adhesive compositions are UV cured under curing conditions of ^{80mW and 1J/cm 2} A resin sample was obtained. Thereafter, CTE was measured for each of the resin sample and the polymer bead sample in the following manner. That is, by using a thermal mechanical analyzer (TMA Q400, TA Instruments) by the method of ASTM E831, the dimension change according to the temperature was measured at a temperature increase rate of 10 °C/min, and the CTE was calculated therefrom. Specifically, after measuring the length changed in the temperature range of 23 ~ 90 ℃, the average value was used as an actual measurement value.

<Measurement of weight loss rate>

First, each photocurable adhesive composition was UV-cured under curing conditions of ^{80mW and 6J/cm 2 to obtain a sample.} Thereafter, the weight reduction rate of each sample was evaluated according to Equation 2 below.

[Equation 2]

Weight loss rate (%) = (Wi-Wf)/Wi * 100

In the formula, Wi is the initial weight of each specimen, and Wf is the weight after each specimen having an initial weight of Wi is immersed in hot water at 90° C. for 10 minutes and then taken out and dried.

<Measurement of spontaneous peeling (peeling time and peeling state)>

First, each photocurable adhesive composition was UV-cured under curing conditions of ^{80mW and 6J/cm 2 to obtain a sample.} Thereafter, spontaneous peeling (peeling time and peeling state) was measured for each of the samples in the following manner. That is, each composition was applied to a thickness of 70 μm on glass (100 mm × 150 mm × thickness 1 mm) and UV cured under the conditions of ^{80 mW and 6 J/cm 2 to prepare a sample.} This sample was immersed in 90 degreeC warm water, the time for glass peeling was measured, and the peeling state was also observed.

<Evaluation of commercialization potential>

When measuring spontaneous peeling, if peeling occurs in advance before immersion in hot water after UV curing, polymer beads protrude over the surface of the film, or if the film is deformed over time after UV curing, it is evaluated as “impossible to commercialize”, otherwise The case was evaluated as "commercializable".

Example One 2 3 4 5 6 7 Viscosity (cPs) 110 2500 1130 1100 1200 1000 1250 DSS
(N/mm ² ) After 1st UV curing 1.4 4.3 3.1 2.1 3.5 3.4 3.0 After 2nd UV curing 1.0 2.5 1.8 2.0 2.0 2.2 2.1 Storage modulus (Pa) 9x10 ⁷ 2x10 ⁸ 2x10 ⁸ 2x10 ⁸ 3x10 ⁸ 2x10 ⁸ 3x10 ⁸ Tg(℃) none none none none none none none Glass Machinability Good Good Good Good Good Good Good CTE resin 370 355 436 390 450 436 436 polymer beads 70 70 70 70 70 70 70 CTE rate 0.18 0.19 0.16 0.18 0.15 0.16 0.16 Weight reduction (%) 1.1 1.0 1.5 1.0 2.4 1.7 1.7 Peeling time (min) 5 4 One 8 One One One peeling state on film on film on film on film on film on film on film Example comparative example 8 9 10 One 2 3 4 Viscosity (cPs) 1800 1230 1100 1250 250 2300 230 DSS
(N/mm ² ) After 1st UV curing 1.7 3.2 3.0 1.4 5.6 4.2 5.2 After 2nd UV curing 1.4 2.0 2.1 0.8 4.4 2.4 4.8 Storage modulus (Pa) 3x10 ⁷ 2x10 ⁸ 2x10 ⁸ 1x10 ⁸ 8x10 ⁷ 2x10 ⁸ 7x10 ⁷ Tg(℃) none none none 40 35 53 34 Glass Machinability Good Good Good error error error error CTE resin 523 488 412 436 261 340 274 polymer beads 70 70 70 not measurable 70 70 70 CTE rate 0.13 0.14 0.16 not measurable 0.26 0.2 0.25 Weight reduction (%) 1.7 1.8 1.9 not measurable 1.5 1.6 1.7 Peeling time (min) One One One not measurable 20 16 20 peeling state on film on film on film on film break on film break commercialization potential possible possible possible impossible possible possible possible comparative example 5 6 7 8 9 10 11 Viscosity (cPs) 2350 1400 980 1080 1100 1200 1120 DSS
(N/mm ² ) After 1st UV curing 4.6 5.4 3.6 not measurable 2.8 3.5 3.1 After 2nd UV curing 3.1 4.5 2.7 not measurable 2.1 1.4 1.5 Storage modulus (Pa) 3x10 ⁸ 3x10 ⁸ 9x10 ⁷ not measurable not measurable 2x10 ⁸ 2x10 ⁸ Tg(℃) 54 46 38 not measurable not measurable 42 41 Glass Machinability error error error error error error error CTE resin 324 320 333 not measurable 448 430 425 polymer beads 70 70 70 70 70 70 - CTE rate 0.21 0.21 0.21 not measurable 0.15 0.16 - Weight reduction (%) 1.7 1.6 1.8 not measurable 0.5 2.3 1.6 Peeling time (min) 17 12 14 not measurable 20 One ≥ 20 peeling state on film break on film not measurable on film on film on film commercialization potential possible possible possible impossible possible impossible possible comparative example 12 13 14 15 Viscosity (cPs) 1140 1270 960 110 DSS
(N/mm ² ) After 1st UV curing 3.2 3.0 2.9 2.2 After 2nd UV curing 1.7 2.1 3.1 2.1 Storage modulus (Pa) 2x10 ⁸ 3x10 ⁸ 6x10 ⁸ 7x10 ⁷ Tg(℃) 41 42 55 31 Glass Machinability error error error error CTE resin 340 440 410 333 polymer beads 70 70 70 70 CTE rate 0.2 0.15 0.17 0.21 Weight reduction (%) 1.5 1.7 1.6 1.8 Peeling time (min) 12 One One One peeling state on film on film on film on film commercialization potential possible impossible possible impossible

Referring to Table 2, the photocurable adhesive compositions prepared in Examples 1 to 10 showed similar viscosity, DSS, and storage modulus compared to the photocurable adhesive compositions prepared in Comparative Examples 1 to 15.

In addition, the photocurable adhesive composition prepared in Examples 1 to 10 has no glass transition temperature (Tg), a low CTE ratio (less than 0.2), a high weight reduction rate (1% or more), and a short peeling time (10 minutes) less), and the peeling state was excellent (film-like).

On the other hand, the photocurable adhesive compositions prepared in Comparative Examples 1 to 15 showed poor glass workability.

In addition, in the photocurable adhesive composition prepared in Comparative Example 1, the polymer beads (F-36D) were foamed after UV curing, and peeling occurred in advance before immersion in hot water, indicating that commercialization was impossible.

In addition, the photocurable adhesive compositions prepared in Comparative Examples 2 to 7, 9 and 12 had a high CTE ratio (0.2 or more), a low weight loss rate (less than 1%), and/or a long peeling time (10 minutes). above) was found.

In addition, the photocurable adhesive composition prepared in Comparative Example 8 lacks a photopolymerization initiator, and thus photopolymerization does not occur, indicating that commercialization is impossible.

In addition, the photocurable adhesive composition prepared in Comparative Example 10 was found to be impossible to commercialize due to deterioration over time (that is, the film shape was deformed over time after UV curing and hot water immersion).

In addition, it was found that the photocurable adhesive composition prepared in Comparative Example 11 lacked polymer beads, so that the peeling time was excessively long (20 minutes or more).

In addition, the photocurable adhesive composition prepared in Comparative Example 13 had an excessively high content of polymer beads, so that after UV curing, the polymer beads protrude to the surface of the film, making it impossible to control the thickness, so it was found that commercialization was impossible.

In addition, the photocurable adhesive composition prepared in Comparative Example 15 was also found to be impossible to commercialize.

Although the present invention has been described with reference to the embodiments, these are merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible therefrom. Accordingly, the true technical protection scope of the present invention should be determined by the technical spirit of the appended claims.

Claims (6)

an oligomer having one or more (meth)acrylate groups at the end of the molecule and having a molecular weight of 1,000 to 9,000;
a polyfunctional first acrylate compound having two or more (meth)acrylate groups and a hydrophilic group including at least one of a hydroxyl group (-OH) and a carboxyl group (-COOH);
The oligomer and the first acrylate compound are different from each other, and a monofunctional second acrylate compound;
photoinitiator; and
A polymer bead comprising at least one compound of polymethyl methacrylate (PMMA) and polystyrene (PS),
It does not have a glass transition temperature after curing under the curing conditions of 80mW and 1J/cm ^{2 ,}
After curing under curing conditions of 80mW and 6J/cm ² , the weight reduction rate when immersed in hot water at 90° C. for 10 minutes satisfies Equation 1 below,
Based on 100 parts by weight of the total amount of the oligomer, the first acrylate compound and the second acrylate compound, 30 to 70 parts by weight of the oligomer, 10 to 35 parts by weight of the first acrylate compound, and the second acrylic compound A photocurable adhesive composition comprising 20 to 35 parts by weight of a rate compound, 5 to 15 parts by weight of the photopolymerization initiator, and 1 to 5 parts by weight of the polymer beads:
[Equation 1]
Weight loss rate (%) = (Wi-Wf)/Wi * 100 ≥ 1.0
where Wi is the initial weight of the cured product of the photocurable adhesive composition, and Wf is the weight after immersing the cured product of the photocurable adhesive composition having an initial weight of Wi in hot water at 90° C. for 10 minutes and then taking it out and drying it . delete According to claim 1,
The polymer bead is a photocurable adhesive composition that does not foam during UV curing. 4. The method of claim 3,
The polymer bead is a photocurable adhesive composition that does not include acrylonitrile-based beads. An adhesive comprising the photocurable adhesive composition according to any one of claims 1, 3 and 4. The method of claim 1, 3 and 4, comprising: bonding a plurality of members using the photocurable adhesive composition according to any one of claims 1 to 4 to form a first laminate;
forming a second laminate including a primary cured product by primary curing the photocurable adhesive composition in the laminate;
forming a third laminate by processing the second laminate;
further curing the primary cured product in the third laminate to form a fourth laminate including the secondary cured product; and
Temporarily fixing the member comprising the step of immersing the fourth laminate in water to remove the secondary cured product in the fourth laminate.

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