JP2008159743A - Sealing material, and formation method and apparatus thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sealing material and a sealing material for electronic components that are improved in shock resistance, moisture resistance, and productivity, and also to provide a formation method and a forming apparatus of the sealing material. <P>SOLUTION: The sealing material is made of a cured product formed by curing at least two kinds of compositions containing a photopolymerization compound. The sealing material comprises: a first resin curing section where the tensile elastic modulus of the cured product after curing the first composition ranges from 1 to 500 MPa; and a second resin curing section where the percentage of water absorption of the cured product after curing the second composition, ranges from 0 to 1%. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a sealing material, a sealing material for electronic components, a method for forming a sealing material, and a sealing material forming apparatus.

  Conventionally, there are electronic components in which electronic component elements such as semiconductor chips and capacitors are arranged on a circuit board. Such an electronic component has an electronic component element mounted on a ceramic circuit board, a paste-like electronic component encapsulant is applied from the top, and the coating film is thermally cured to form an electronic component encapsulant film. Was. The sealing material film protects the wiring pattern formed on the electronic component element and the circuit board from external impacts, moisture, and the like.

  Patent Document 1 discloses a method of sealing by dropping a sealing material from a syringe nozzle onto a joint portion of a semiconductor element. In this method, since the specified material of one liquid is dropped, the position accuracy and productivity are difficult, and since it is a potting apparatus for one liquid, it is difficult to make the sealing material multifunctional.

  In particular, the necessary functions of a sealing material for electronic parts are impact resistance and moisture resistance. However, Patent Document 2 discloses a technique for improving impact resistance, moisture resistance and the like using a thermosetting resin. ing. However, the thermosetting resin has a problem in that the reliability and productivity with respect to the electronic component are poor because high temperature treatment is required and the reaction time (tact time) is long.

Therefore, Patent Document 3 discloses an inkjet head using a photocurable resin as a sealing material from the viewpoint of mass productivity. In the method disclosed in Patent Document 3, a room temperature curable sealing material and a photocurable sealing material are used. Since these are a sealing material that is cured by heat at room temperature and a sealing material that is cured by photoexcitation, the curing mechanism is different and the curing (reaction) time is different. Therefore, the manufacturing method is limited. Due to these factors, the production efficiency was poor and was a problem.
Japanese Patent No. 2983267 JP 2005-146008 A JP-A-8-58078

  The present invention has been made in view of the above-described problems, and its solution is to provide a sealing material and an electronic component sealing material that are excellent in impact resistance, moisture resistance, etc., and excellent in productivity. It is. Moreover, it is providing the formation method and formation apparatus of the said sealing material.

  The above-mentioned problem according to the present invention is solved by the following means.

  1. A sealing material comprising a cured product formed by curing at least two kinds of compositions containing a photopolymerizable compound, and the cured product after the first composition is cured has a tensile modulus of 1 Sealing comprising: a first resin cured portion of ˜500 MPa; and a second resin cured portion having a water absorption of 0 to 1% after cured of the second composition Wood.

  2. 2. The sealing material according to 1 above, which is used as a sealing material for electronic parts.

  3. 3. The sealing material according to 1 or 2, wherein the at least two kinds of compositions containing the photopolymerizable compound are at least two kinds of inkjet inks.

  4). 4. The method for forming a sealing material according to claim 1, wherein the sealing material is formed by an inkjet method.

  5. The sealing material according to 4 above, wherein the temperature of the ink for forming the sealing material and the inkjet recording head is heated to 35 to 100 ° C., and then the ink is discharged and cured to form the sealing material. Forming method of the stop material.

  6). 6. The method for forming a sealing material according to 4 or 5, wherein after the ink has landed on the object to be sealed, the ink is irradiated with light and cured to form a sealing material.

  7. A sealing material forming apparatus used in the method for forming a sealing material according to any one of 4 to 6 above, wherein the light irradiation means, the means for measuring ink temperature, the means for heating ink, and the recording head A sealing material forming apparatus comprising: means for controlling the temperature of the ink; means for detecting position information of an electronic component; and means for controlling ejection of ink from the recording head in accordance with the position information.

  8). 8. The sealing material forming apparatus according to claim 7, comprising: means for heating the electronic component; and means for controlling the temperature of the electronic component.

  By the above means of the present invention, it is possible to provide a sealing material and an electronic component sealing material which are excellent in impact resistance, moisture resistance and the like and excellent in productivity. Moreover, the formation method and formation apparatus of the said sealing material can be provided.

  In other words, important functions and performance as a sealing material are impact resistance, moisture resistance and productivity, etc., but in the present invention, for improvement of impact resistance and moisture resistance, special photopolymerizable compounds having different performances are used. It can achieve by using 2 or more types of compositions to contain. In addition, to improve the productivity (tact time) problem, by unifying the curing mechanism using a composition containing a polymerizable compound that is cured by light, problems due to differences in the curing mechanism are avoided. Can be achieved. Furthermore, a sealing material can be formed on an electronic component with high positional accuracy by a method using an inkjet method and a sealing material forming apparatus using the composition (for example, an ink composition for inkjet). Accordingly, it is possible to provide an electronic component that is protected by a sealing material that is excellent in impact resistance, moisture resistance, and the like and that is excellent in productivity, and whose performance is stabilized.

  The encapsulant of the present invention is an encapsulant comprising a cured product formed by curing at least two kinds of compositions containing a polymerizable compound, and curing after curing the first composition. A first resin cured part having a tensile modulus of 1 to 500 MPa, and a second resin cured part having a water absorption of 0 to 1% after the second composition is cured. It is characterized by that. This feature is a technical feature common to the inventions according to claims 1 to 8.

  In the present application, the “cured product” refers to a composition (including a resin) obtained by curing a composition containing a photopolymerizable compound, a polymerization initiator and other compounds by polymerization or a crosslinking reaction with light. Say. Here, the “photopolymerizable compound” includes those having a chemical structure such as a monomer, an oligomer, and a polymer (resin) as described later.

  Moreover, the tensile elasticity modulus of the hardened | cured material of the composition based on this invention is a measured value obtained by the measurement based on a "JISK7127" test method. The water absorption is a measured value obtained by measurement based on the “JIS K 6911” test method.

  Hereinafter, the present invention and its components will be described in detail.

(Photopolymerizable compound-containing composition used in the present invention)
In the present invention, at least two kinds of compositions containing a photopolymerizable compound are used, and the first cured resin having a cured product having a tensile elastic modulus of 1 to 500 MPa after curing the first composition. Part and the 2nd resin hardening part whose water absorption of the hardened | cured material after hardening a 2nd composition is 0 to 1%, It is characterized by the above-mentioned.

  The composition used in the present invention is a composition in which when the composition is irradiated with light, the composition initiates a polymerization reaction by the irradiated light and cures to form a cured product (resin). It needs to be.

  In addition, it is preferable that the said composition is a composition containing the various photopolymerizable compounds mentioned later. In particular, the composition is preferably an inkjet ink (also referred to as “inkjet ink composition” or simply “ink composition”).

  Here, as light to irradiate, it is preferable to select the light of a suitable wavelength range according to the light absorption characteristic of the said composition. In the present invention, particularly preferred light is so-called “active light”. That is, light in the ultraviolet to visible light region having a wavelength of 180 to 500 nm is preferable.

  Examples of the light source include a low-pressure mercury lamp, a high-pressure mercury lamp, an ultrahigh-pressure mercury lamp, a metal halide lamp, a chemical lamp, a black light lamp, a mercury-xenon lamp, an excimer lamp, a short arc lamp, a helium / cadmium laser, an argon laser, and an excimer. A laser, a light emitting diode (LED), and sunlight are mentioned.

  The composition according to the present invention comprises a monomer, oligomer or polymer of a photopolymerizable compound such as a radical polymerizable compound or a cationic polymerizable compound, or a mixture thereof, a photo radical polymerization initiator, and a photo cation described in detail below. It is necessary to contain a polymerization initiator or the like as a component.

  As the photopolymerizable composition, a photo-radical polymerizable composition that is polymerized by a radical reaction upon light irradiation, and a cationic polymerizable composition that is polymerized by a cationic chemical species as a reactive species are known. Yes. These are described in, for example, JP-A-7-159983, JP-B-7-31399, JP-A-8-224982, and JP-A-10-863. In addition, recently, photocationic polymerization type photocurable resins sensitized to a long wavelength region longer than visible light are also disclosed in, for example, JP-A-6-43633 and JP-A-8-324137.

  Japanese Patent Application Laid-Open No. 2005-153386 discloses a photocured polyvinyl alcohol derivative polymer. As maleimide derivatives, JP-A-61-250064, JP-A-62-79243, JP-A-6-298817, JP-A-11-124403 and the like are disclosed. In the present invention, any material can be used as long as the above requirements are satisfied.

  In the present invention, the influence of the material on the human body (skin irritation, etc.), a cationic polymerization system, a photocurable polyvinyl alcohol derivative, maleimide and the like are preferable. More preferably, a low viscosity is essential for inkjet applications, and since it is difficult to receive polymerization inhibition by oxygen and chemical resistance, water resistance, and high surface strength that are desired to be increased in molecular weight can be expected, a cationic polymerization system and a photocurable polyvinyl alcohol derivative are used. preferable.

  Hereinafter, various components of the composition according to the present invention will be described.

<Radically polymerizable compound>
A preferable compound as the radical polymerizable compound is a compound having an ethylenically unsaturated bond capable of radical polymerization and any compound having at least one ethylenically unsaturated bond capable of radical polymerization in the molecule. Good. Those having chemical structural forms such as monomers, oligomers, polymers and the like are included. Only one kind of radically polymerizable compound may be used, or two or more kinds thereof may be used in combination at an arbitrary ratio in order to improve desired properties.

  Examples of compounds having an ethylenically unsaturated bond capable of radical polymerization include unsaturated carboxylic acids such as acrylic acid, methacrylic acid, itaconic acid, crotonic acid, isocrotonic acid, maleic acid and their salts, esters, urethanes, amides. And radically polymerizable compounds such as unsaturated monomers, acrylonitrile, styrene, various unsaturated polyesters, unsaturated polyethers, unsaturated polyamides, and unsaturated urethanes.

  Specifically, 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, butoxyethyl acrylate, carbitol acrylate, cyclohexyl acrylate, tetrahydrofurfuryl acrylate, benzyl acrylate, bis (4-acryloxypolyethoxyphenyl) propane, neopentyl glycol Diacrylate, 1,6-hexanediol diacrylate, ethylene glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, polypropylene glycol diacrylate, pentaerythritol triacrylate, pentaerythritol Tetraacrylate, dipentaery Acrylic acid derivatives such as lithol tetraacrylate, trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate, oligoester acrylate, N-methylol acrylamide, diacetone acrylamide, epoxy acrylate, methyl methacrylate, n-butyl methacrylate, 2-ethylhexyl methacrylate , Lauryl methacrylate, allyl methacrylate, glycidyl methacrylate, benzyl methacrylate, dimethylaminomethyl methacrylate, 1,6-hexanediol dimethacrylate, ethylene glycol dimethacrylate, triethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, polypropylene glycol dimethacrylate, trimethylol Methacryl derivatives such as tan trimethacrylate, trimethylolpropane trimethacrylate, 2,2-bis (4-methacryloxypolyethoxyphenyl) propane, and other derivatives of allyl compounds such as allyl glycidyl ether, diallyl phthalate, triallyl trimellitate More specifically, Yamashita Junzo, “Crosslinker Handbook”, (1981 Taiseisha); Kato Kiyomi, “UV / EB Curing Handbook (Materials)” (1985, Polymer Publication) ); Rad-Tech Study Group, “Application and Market of UV / EB Curing Technology”, p. 79, (1989, CMC); Eiichiro Takiyama, “Polyester Resin Handbook”, (1988, Nikkan Kogyo Shimbun) Commercially available products described in the above, or radically polymerizable or crosslinkable monomers known in the industry Oligomers and polymers can be used.

  Examples of other radical polymerization compounds include derivatives of allyl compounds such as allyl glycidyl ether, diallyl phthalate, and triallyl trimellitate. More specifically, Shinzo Yamashita, “Crosslinker Handbook”, (1981 Taiseisha); Kato Kiyosumi, “UV / EB Curing Handbook (Materials)” (1985, Polymer Publications); Radtech Study Group, “Application and Market of UV / EB Curing Technology”, p. 79, (1989, CMC); written by Eiichiro Takiyama, “Polyester Resin Handbook”, (1988, Nikkan Kogyo Shimbun) Also known radically polymerizable or crosslinkable monomers, oligomers and polymers can be used.

  The addition amount of the radical polymerizable compound to the photocurable composition (inkjet ink composition or the like) according to the present invention is preferably 1 to 97% by mass.

<Cationically polymerizable compound>
As the cationically polymerizable compound, for example, an epoxy type ultraviolet curable prepolymer or a monomer containing two or more epoxy groups in one molecule can be used, which is a type in which polymerization is caused by cationic polymerization. Examples of such prepolymers include alicyclic polyepoxides, polyglycidyl esters of polybasic acids, polyglycidyl ethers of polyhydric alcohols, polyglycidyl ethers of polyoxyalkylene glycols, and polyglycidyls of aromatic polyols. Examples include ethers, hydrogenated compounds of polyglycidyl ethers of aromatic polyols, urethane polyepoxy compounds, and epoxidized polybutadienes. These prepolymers and monomers can be used alone or in a mixture of two or more.

  Other examples of the cationic polymerizable composition contained in the cationic polymerization photocurable resin include (1) styrene derivatives, (2) vinyl naphthalene derivatives, (3) vinyl ethers, and (4) N-vinyl compounds described below. (5) Oxetanes and the like.

(1) Styrene derivatives For example, styrene, p-methylstyrene, p-methoxystyrene, β-methylstyrene, p-methyl-β-methylstyrene, α-methylstyrene, p-methoxy-β-methylstyrene, etc. (2) Vinyl naphthalene derivatives For example, 2-vinyl naphthalene, α-methyl-2-vinyl naphthalene, β-methyl-2-vinyl naphthalene, 4-methyl-2-vinyl naphthalene, 4-methoxy-2-vinyl naphthalene, etc. (3) Vinyl ether For example, ethylene glycol divinyl ether, diethylene glycol divinyl ether, triethylene glycol divinyl ether, propylene glycol divinyl ether, dipropylene glycol divinyl ether, butanediol divinyl ether, hexanediol divinyl ether , Di- or trivinyl ether compounds such as cyclohexanedimethanol divinyl ether and trimethylolpropane trivinyl ether, ethyl vinyl ether, n-butyl vinyl ether, isobutyl vinyl ether, octadecyl vinyl ether, cyclohexyl vinyl ether, hydroxybutyl vinyl ether, 2-ethylhexyl vinyl ether, cyclohexane dimethanol mono Examples thereof include monovinyl ether compounds such as vinyl ether, n-propyl vinyl ether, isopropyl vinyl ether, isopropenyl ether-O-propylene carbonate, dodecyl vinyl ether, diethylene glycol monovinyl ether, and octadecyl vinyl ether.

(4) N-vinyl compounds For example, N-vinylcarbazole, N-vinylpyrrolidone, N-vinylindole, N-vinylpyrrole, N-vinylphenothiazine, N-vinylacetanilide, N-vinylethylacetamide, N-vinylsuccinimide , N-vinylphthalimide, N-vinylcaprolactam, N-vinylimidazole, etc. (5) Oxacene compounds Means compounds having an oxetane ring, and are described, for example, in JP-A Nos. 2001-220526 and 2001-310937. Known oxetane compounds can be used. When the compound having 5 or more oxetane rings is used as the oxetane compound according to the present invention, the viscosity of the ink composition becomes high, so that handling becomes difficult, and the glass transition temperature of the ink composition becomes high. The resulting cured product will not be sufficiently sticky. The oxetane compound is preferably a compound having 1 to 4 oxetane rings.

  Although the specific example of an oxetane compound is demonstrated, it is not limited to these. An example of the compound having one oxetane ring is a compound represented by the following general formula (1).

In the general formula (1), R ¹ is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms such as a methyl group, an ethyl group, a propyl group, or a butyl group, a fluoroalkyl group having 1 to 6 carbon atoms, an allyl group, or an aryl group. , Furyl group or thienyl group. R ² is an alkyl group having 1 to 6 carbon atoms such as methyl group, ethyl group, propyl group, butyl group, 1-propenyl group, 2-propenyl group, 2-methyl-1-propenyl group, 2-methyl- C2-C6 alkenyl group such as 2-propenyl group, 1-butenyl group, 2-butenyl group, 3-butenyl group, phenyl group, benzyl group, fluorobenzyl group, methoxybenzyl group, phenoxyethyl group, etc. A group having an aromatic ring, an alkylcarbonyl group having 2 to 6 carbon atoms such as an ethylcarbonyl group, a propylcarbonyl group, and a butylcarbonyl group, an alkylcarbonyl group having 2 to 6 carbon atoms such as an ethoxycarbonyl group, a propoxycarbonyl group, and a butoxycarbonyl group; Alkoxycarbonyl group, ethylcarbamoyl group, propylcarbamoyl group, butylcarbamoyl group, pentylcarbamoyl Is N- alkylcarbamoyl group having a carbon number of 2-6 and the like. As the oxetane compound used in the present invention, it is particularly preferable to use a compound having one oxetane ring because the resulting composition has excellent tackiness, low viscosity and excellent workability.

  An example of a compound having two oxetane rings includes a compound represented by the following general formula (2).

In the general formula (2), R ¹ is the same group as that in the general formula (1). R ³ is, for example, a linear or branched alkylene group such as an ethylene group, a propylene group or a butylene group, a linear or branched poly (alkyleneoxy) such as a poly (ethyleneoxy) group or a poly (propyleneoxy) group. ) Group, propenylene group, methylpropenylene group, butenylene group or other linear or branched unsaturated hydrocarbon group, alkylene group containing carbonyl group or carbonyl group, alkylene group containing carboxyl group, alkylene containing carbamoyl group Group.

Moreover, as R < ³ >, the polyvalent group selected from the group shown by the following general formula (3), (4) and (5) can also be mentioned.

In the general formula (3), R ⁴ represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, a propyl group, or a butyl group, a methoxy group, an ethoxy group, a propoxy group, or a butoxy group. An alkoxy group having 1 to 4 carbon atoms, a halogen atom such as a chlorine atom or a bromine atom, a nitro group, a cyano group, a mercapto group, a lower alkyl carboxyl group, a carboxyl group, or a carbamoyl group.

In the general formula (4), R ⁵ represents an oxygen atom, a sulfur atom, a methylene group, NH, SO, SO 2, C (CF ₃ ) ₂ , or C (CH ₃ ) ₂ .

In General formula (5), R < ⁶ > is a C1-C4 alkyl group, such as a methyl group, an ethyl group, a propyl group, a butyl group, or an aryl group. n is an integer of 0-2000. R ⁷ is a methyl group, an ethyl group, a propyl group, a butyl group having 1 to 4 carbon atoms, or an aryl group. R ⁷ may further include a group selected from the group represented by the following general formula (6).

In General formula (6), R < ⁸ > is a C1-C4 alkyl group, such as a methyl group, an ethyl group, a propyl group, a butyl group, or an aryl group. m is an integer of 0-100.

  Specific examples of the compound having two oxetane rings include the following exemplified compounds 1 and 2.

Illustrative compound 1 is a compound in which R ¹ is an ethyl group and R ³ is a carbonyl group in general formula (2). Exemplary compound 2 is a compound in which, in the general formula (2), R ¹ is an ethyl group, R 3 is the general formula (5), R ⁶ and R ⁷ are methyl groups, and n is 1.

Among the compounds having two oxetane rings, preferred examples other than the above compounds include compounds represented by the following general formula (7). In general formula (7), R ¹ has the same meaning as R ¹ in the general formula (1).

  An example of a compound having 3 to 4 oxetane rings is a compound represented by the following general formula (8).

In the general formula (8), R ¹ is the same meaning as R ¹ in the general formula (1). As R ⁹ , for example, a branched alkylene group having 1 to 12 carbon atoms such as groups represented by the following A to C, a branched poly (alkyleneoxy) group such as a group represented by the following D, or the following E And branched polysiloxy groups such as those shown. j is 3 or 4.

In the above A, R ¹⁰ is a lower alkyl group such as a methyl group, an ethyl group or a propyl group. Moreover, in said D, p is an integer of 1-10.

  Illustrative compound 3 is an example of a compound having four oxetane rings.

  Furthermore, examples of the compound having 1 to 4 oxetane rings other than those described above include compounds represented by the following general formula (9).

In the general formula (9), R ⁸ has the same meaning as R ⁸ in the general formula (6). R ¹¹ is an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, a propyl group or a butyl group or a trialkylsilyl group, and r is 1 to 4. R ¹ has the same meaning as R ¹ in the general formula (6).

  Preferred specific examples of the oxetane compound used in the present invention include the exemplified compounds 4, 5, and 6 shown below.

  The production method of each compound having an oxetane ring described above is not particularly limited, and may be a conventionally known method, for example, Pattison (DB Pattison, J. Am. Chem. Soc., 3455, 79). (1957)) discloses a method for synthesizing an oxetane ring from a diol. In addition to these, compounds having 1 to 4 oxetane rings having a high molecular weight of about 1000 to 5000 are also included. Examples of these specific compounds include the following compounds.

  The addition amount of the cationic polymerizable composition to the photocurable ink is preferably 1 to 97% by mass.

<Photocurable polyvinyl alcohol derivative>
Photocuring polyvinyl alcohol derivatives include saponified polyvinyl acetate, polyvinyl acetal, polyethylene oxide, polyalkylene oxide, polyvinyl pyrrolidone, polyacrylamide, hydroxyethyl cellulose, methyl cellulose, hydroxypropyl cellulose, or a derivative of the hydrophilic resin, and It is at least one selected from the group consisting of these copolymers, or the hydrophilic resin is modified with a modifying group such as a photodimerization type, a photodecomposition type, a photopolymerization type, a photo-denaturation type, or a photodepolymerization type It is a thing.

  As the photodimerization-type modifying group, those having a diazo group, a cinnamoyl group, a styrylpyridinium group, or a stilquinolium group introduced are preferable, and a resin dyed with a water-soluble dye such as an anionic dye after photodimerization is preferable. Examples of such resins include resins having a cationic group such as a primary amino group or a quaternary ammonium group, such as JP-A Nos. 62-283339, 1-198615, and 60-252341. Photosensitive resins (compositions) described in JP-A-56-67309, JP-A-60-129742, etc., resins that become cationic after curing, such as azide groups that become amino groups by curing treatment, such as Examples thereof include photosensitive resins (compositions) described in JP-A-56-67309.

  The addition amount of the photocurable polyvinyl alcohol derivative to the photocurable ink is preferably 1 to 97% by mass.

<Maleimide derivative>
A known compound can be used as the maleimide derivative. For example, JP 61-250064, JP 62-64813, JP 62-79243, JP 6-298817, JP 11-124403, JP 11-292874, JP 11-11 -302278, JP 2000-264922, "Polymer Materials Science and Engineering" Vol. 72, 470-472 (1995), "Polymer Preprints" Vol. 37, 348-349 (1996), "The 4th Fusion UV Technology Seminar", pages 43-77 (1996), "Polymer Letters", Volume 6, pages 883-888 (1998), "The 9th Fusion UV Technology Seminar", pages 5-20 (2001) etc. are used Kill.

  The amount of maleimide added to the photocurable ink is preferably 1 to 97% by mass.

  In the present invention, the cationic polymerizable compound and the radical polymerizable compound may be used alone in a photocurable ink or may be mixed.

<Photocuring accelerator: photopolymerization initiator, etc.>
It is necessary to add a photopolymerization initiator, an initiation aid, and a photocuring acceleration aid for initiating the polymerization reaction of the polymerizable composition by light irradiation to the composition according to the present invention (inkjet ink composition, etc.). .

  As the photopolymerizable composition, those suitable for each of a radically polymerizable composition, a cationic polymerizable composition, a polymerized composition made of a photocurable polyvinyl alcohol derivative, and a polymerizable composition made of a maleimide derivative are applied.

  Although there is no restriction | limiting in particular about the photoinitiator to apply, As an example, benzophenone, hydroxybenzophenone, bis-N, N-dimethylamino benzophenone, bis-N, N-diethylamino benzophenone, 4-methoxy-4'- dimethylamino benzophenone And thioxanthones such as thiophenone, 2,4-diethylthioxanthone, isopropylthioxanthone, chlorothioxanthone, and isopropoxychlorothioxanthone. Anthraquinones such as ethyl anthraquinone, benzanthraquinone, aminoanthraquinone and chloroanthraquinone, and acetophenones. Benzoin ethers such as benzoin methyl ether, 2,4,6-trihalomethyltriazines, 1-hydroxycyclohexyl phenyl ketone, 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer, 2- (o- Chlorophenyl) -4,5-di (m-methoxyphenyl) imidazole dimer, 2- (o-fluorophenyl) -4,5-phenylimidazole dimer, 2- (o-methoxyphenyl) -4,5 -Phenylimidazole dimer, 2- (p-methoxyphenyl) -4,5-diphenylimidazole dimer, 2, -di (p-methoxyphenyl) -5-phenylimidazole dimer, 2- (2, 2,4,5-triarylimidazole dimer of 4-dimethoxyphenyl) -4,5-diphenylimidazole dimer, N-dimethylketal, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-1- Propanone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propan-1-one , Phenanthrenequinone, 9,10-phenanthrenequinone, methylbenzoin, benzoins such as ethylbenzoin, 9-phenylacridine, acridine derivatives such as 1,7-bis (9,9'-acridinyl) heptane, titanocene, bisacyl Phosphine oxide, diazonium, ammonium, iodonium, sulfonium, phosphonium and Onium salt consisting of benzophenone ammonium salts, sulfonated, halides, iron Aalen compounds, titanocene compounds, and the like. The above may be used alone or in combination.

  As photopolymerization initiators, in addition to the above-mentioned compounds, “Application and Market of UV / EB Curing Technology” (CMC Publishing Co., Ltd., edited by Yoneho Tabata, edited by Radtech Study Group), “Organic Materials for Imaging” ( It is good also as applying the compound known by literatures, such as the description on pages 187-192 of an organic electronics material study group edition, Bunshin publication, 1993).

  Initiating aids and photocuring accelerators can also be used to advance the photopolymerization (curing) reaction.

  Here, the “initiating aid” is a sensitizing dye that improves the generation efficiency of radicals or acids of the initiator by donating energy to the initiator by light irradiation, electron donation, electron attraction, heat generation, etc. Is applied in combination with an initiator.

  Examples of the initiator include xanthene, thioxanthone dye, ketocoumarin, thioxanthene dye, cyanine, phthalocyanine, merocyanine, porphyrin, spiro compound, ferrocene, fluorene, fulgide, imidazole, perylene, phenazine, phenothiazine, polyene, azo compound, diphenylmethane , Triphenylmethane, polymethine acridine, coumarin, ketocoumarin, quinacridone, indigo, styryl, pyrylium compound, pyromethene compound, pyrazolotriazole compound, benzothiazole compound, barbituric acid derivative, thiobarbituric acid derivative and the like can be applied.

  In addition to the above-mentioned compounds, it is well known that the initiator acts as a sensitizing dye in documents such as “Development technology of polymer additives” (CMC Publishing Co., Ltd., supervised by Junichi Daikatsu). The substance may be applied. The initiation assistant can also be regarded as a constituent element that forms part of the initiator.

  In addition to these photoinitiators, an accelerator aid may be added to accelerate the photopolymerization (curing) reaction. Examples of these include ethyl p-dimethylaminobenzoate, isoamyl p-dimethylaminobenzoate, ethanolamine, diethanolamine, triethanolamine and the like.

  The photopolymerization (curing) accelerator is preferably added in an addition amount of 0.1 to 10% by mass. When the addition amount of the initiator is less than 0.1% by mass, the photocurable ink that has landed on the electronic component does not cure quickly, which causes a problem that it becomes difficult to control the dot diameter and the dot shape.

  The composition according to the present invention (inkjet ink composition, etc.) is shaped in consideration of impact strength, moisture resistance, etc., for bonding reliability of electronic parts and surface protection (humidity dependency, strength, etc.). Yes. In general, there is no material for a composition (ink composition or the like) satisfying both the bonding reliability and the surface protection, which is a problem.

  Therefore, in the present invention, a photocurable ink jet ink having the following specific physical properties was prepared, and the object of the present invention could be achieved.

  (1) The tensile modulus of the cured product (resin) of the ink composition according to the present invention is from the viewpoint of mechanical strength such as impact resistance, bonding reliability of electronic parts, surface protection characteristics (strength), and the like. Although it is required to be 1 to 500 MPa, it is preferably 1 to 300 MPa. If it is less than 1 Mpa or more than 500 Mpa, mechanical strength such as bonding reliability and surface protection characteristics (strength) of electronic components deteriorates, which becomes a problem.

  In order to set the tensile elastic modulus of the cured product (resin) of the ink composition to 1 to 500 MPa, in addition to the photopolymerizable compound, an epoxy compound, a urethane compound, a silicon compound, a polyester compound, cyano Synthetic rubber compounds such as acrylate compounds, nitrile rubbers, thermoplastic elastomers, urethane compounds, alicyclic compounds, long chain alkyl compounds, rubber compounds, and the like can be used. That is, these can be adjusted to a desired tensile modulus by using one or more of them. The compound is preferably a photopolymerizable (curable) compound in order to increase the curing rate.

  Moreover, a commercially available polymerizable compound can be used as the polymerizable compound. For example, as the radical polymerizable compound, urethane (meth) acrylate such as NK Oligo UA-160TM, NK Oligo U-108A, NK Oligo UA-4200 (Shin Nakamura Chemical Co., Ltd.), NK Ester A-DCP, NK Ester Alkyl (meth) acrylates such as A-IB, NK ester A-BEPD (Shin Nakamura Chemical Co., Ltd.), light acrylate 1.6HX-A (Kyoeisha Chemical Co., Ltd.), NK ester A-PTMG65, NK ester A -TMPT-3EO (Shin Nakamura Chemical Co., Ltd.), light acrylate PTMGA-250 (Kyoeisha Chemical Co., Ltd.) glycol-type (meth) acrylates, etc. can be used. As the cationic polymerizable compound, oxetane compounds such as OXT212, OXT101 (Toagosei Co., Ltd.), exemplified compound 6 and the like can be used.

<Tensile modulus>
The tensile modulus of the cured product (resin) of the ink composition according to the present invention can be measured according to the test method defined in “JIS K 7127” or “ASTM D638”. Measured according to the “K 7127” test method.

  When an external force is applied to the cured product (resin) to deform it, the stress caused by the external force and the strain caused by the deformation are proportional to each other in a range where the deformation is not so great (Hooke's law). The tensile elastic modulus of the cured product (resin) is obtained by using the proportional constant at this time as the elastic modulus. That is, the elastic modulus C is expressed by C = (stress) / (strain).

  (2) The water absorption rate of the cured product (resin) of the ink composition according to the present invention needs to be 0 to 1% from the viewpoint of moisture resistance and the like, but is preferably 0 to 0.5%. . In addition, the said water absorption is a measured value obtained by measuring based on a "JIS K 6911" test method.

  In order to set the water absorption rate of the cured product (resin) of the ink composition to 0 to 1%, a resin material that is generally used such as the polymerizable compound is used as long as it does not violate the gist of the present invention and the above requirements. Can be used without limitation.

  In addition to the photopolymerizable compounds, for example, polyester compounds, cyanoacrylate compounds, nitrile rubber, thermoplastic elastomers and other synthetic rubber compounds, acrylic compounds, epoxy compounds, olefin compounds, polycarbonate compounds, norbornene compounds Compounds, silicon compounds, alicyclic compounds, long-chain alkyl compounds, paraffin waxes, olefin waxes, polyethylene waxes, polypropylene waxes, carnauba waxes, and the like can be used. That is, these can be adjusted to a desired water absorption rate by using one or more of them. In order to increase the curing rate, it is necessary to be a photopolymerizable (curable) compound. The compound is preferably a photopolymerizable (curable) compound in order to increase the curing rate.

  Moreover, a commercially available polymerizable compound can be used as the polymerizable compound. For example, as a radically polymerizable compound, NK ester A-DCP, NK ester A-IB, NK ester A-BEPD (Shin Nakamura Chemical Co., Ltd.), light acrylate 1.6HX-A (Kyoeisha Chemical Co., Ltd.), etc. Glycol (meth) acrylates such as NK ester A-PTMG65, NK ester A-TMPT-3EO (Shin Nakamura Chemical Co., Ltd.), light acrylate PTMGA-250 (Kyoeisha Chemical Co., Ltd.) Etc. can be used. As the cationic polymerizable compound, oxetane compounds such as OXT212, OXT101 (Toagosei Co., Ltd.), exemplified compound 6 and the like can be used.

In the present invention, it is necessary to satisfy the requirements for the tensile elastic modulus and the water absorption rate. However, ink jet ink having other functions and characteristics may be put in an ink tank of another unit and discharged from the recording head. For example, in order to obtain endurance reliability in a high temperature and high humidity environment, an ink whose linear thermal expansion coefficient of the cured product (resin) of the ink composition is 1.0 × 10 ⁻⁴ / K or less is used in combination. There is no particular limitation, and an ink or the like considering the adhesion may be used in order to improve the adhesion between the cured inks.

  To the ink-jet ink according to the present invention, a basic compound, a polymer dispersant, a viscosity modifier, a polymerization inhibitor, an antioxidant, a surfactant, a leveling additive, an organic solvent, and the like are added as necessary. Also good.

  When preparing ink jet ink, in order to obtain a uniform dispersion, ball mill, sand mill, attritor, roll mill, agitator, Henschel mixer, colloid mill, ultrasonic homogenizer, pearl mill, wet jet mill, paint shaker, etc. Can be used.

<Discharge conditions for inkjet ink>
In the present invention, it is preferable from the viewpoint of ejection stability that the ink for forming the sealing material and the temperature of the inkjet recording head are heated to 35 to 100 ° C. and then the ink is ejected. Actinic radiation curable ink has a large viscosity fluctuation range due to temperature fluctuation, and the viscosity fluctuation directly affects the droplet size and droplet ejection speed, thereby deteriorating the positional accuracy to electronic parts and the target function. It becomes a problem. It is necessary to keep the temperature constant while raising the ink temperature. The control range of the ink temperature is set temperature ± 5 ° C., preferably set temperature ± 2 ° C., more preferably set temperature ± 1 ° C.

  In the present invention, it is preferable that the minimum amount of liquid droplets discharged from each nozzle is 2 to 30 pl. Originally, in order to form a high position accuracy, it is necessary for the amount of droplets to be within this range, but when discharging with this amount of droplets, the aforementioned discharge stability becomes particularly severe.

<Curing conditions for inkjet ink>
In the present invention, after the ink has landed on an object to be sealed such as an electronic component, the ink is irradiated with light after 0.001 to 5.0 seconds and cured to form a sealing material. preferable.

Moreover, it is preferable that the illumination intensity in the base-material (electronic component) surface of the light ray irradiated from a light source part for ink hardening exists in the range of 0.1-1000 mW / cm < ² >. The ink satisfying the above-mentioned requirements according to the present invention is preferable for shortening the production time because it is rapidly cured and can be used at an illuminance of 0.1 to 500 mW / cm ² .

  In the present invention, there is no particular limitation as long as the total ink film thickness after the ink lands on the electronic component and is cured by irradiating light (active light) has the necessary function on the electronic component. However, since excessively forming on the electronic component affects the shape and thickness of the electronic component itself, it is not preferable to eject ink with an excessive film thickness.

  A basic method of actinic ray irradiation is disclosed in JP-A-60-132767. According to this, the light source is provided on both sides of the head unit, and the head and the light source are scanned by the shuttle method. Irradiation is performed after a certain period of time after ink landing. Further, the curing is completed by another light source that is not driven.

  In US Pat. No. 6,145,979, as an irradiation method, a method using an optical fiber or a method of irradiating a recording unit with UV light by applying a collimated light source to a mirror surface provided on the side surface of the head unit is disclosed. Has been. In the present invention, any of these irradiation methods can be used.

(Encapsulant forming device)
The method for forming a sealing material of the present invention is a method for forming a sealing material by an ink jet method. As a sealing material forming apparatus used for that purpose, a light irradiation means (also referred to as a “light irradiation apparatus”), Means for measuring ink temperature, means for heating ink, means for controlling the temperature of the ink for each recording head, means for detecting position information of an electronic component, and controlling ink ejection from the recording head according to the position information It is preferable from the viewpoint of producing the sealing material of the present invention. Furthermore, it is preferable from the same point of view to include means for heating the electronic component and means for controlling the temperature of the electronic component.

  The “inkjet method” refers to a printing / image forming method of a printer that records by discharging ink from nozzles.

  Hereinafter, an encapsulant forming apparatus according to the present invention will be described with reference to the drawings as appropriate. Note that the sealing material forming apparatus shown in the drawings is an embodiment of a sealing material forming apparatus that can be preferably used in the present invention, and the present invention is not limited to the sealing material forming apparatus exemplified here.

  In addition, although the sealing material of this invention and its formation method can apply various articles | goods as a sealing target object, below, the sealing material of this invention is applied suitably as a sealing target object. An apparatus for forming an encapsulant by selecting an electronic component, landing the ink on the electronic component using the ink-jet ink according to the present invention, irradiating the ink with ultraviolet rays, and curing the ink. And a method for forming a sealing material using the same.

  FIG. 1 is a front view showing an example of a configuration of a main part used in a serial printing method in a sealing material forming apparatus (without an electronic component heater) according to the present invention. FIG. 2 is a side view of the apparatus.

  The sealing material forming apparatus 1 includes an electronic component position detector (means for detecting position information of an electronic component) 11, a transport member 99 that transports the sealing surface of the electronic component 4 upward, a head carriage 14, a recording head 5, and the like. 6, 7, 8, light irradiation means 9, 10, and flat platen part 2. Before and after the platen 2, conveying rollers 3a and 3b are disposed as a conveying mechanism. Each of the transport rollers 3a and 3b is rotated in a predetermined direction around the axis before and after the platen 2, and the transport member 99 is moved along the transport direction A along with the rotation of the transport rollers 3a and 3b. Is supposed to be transported. In the present invention, the electronic component 4 and the conveying member 99 are separately configured. However, in order to improve the conveying accuracy, a base material in which the conveying member and the electronic component are integrated may be used.

  As shown in FIG. 1, the sealing material forming apparatus 1 has a rod-shaped guide rail 12, and a carriage 14 is supported on the guide rail 12. The carriage 14 reciprocates along the guide rail 12 in the scanning direction B by a carriage drive mechanism 22 (see FIG. 5).

  Mounted on the carriage 14 are four recording heads 5, 6, 7, and 8 for ejecting the ink-jet ink according to the present invention toward the recording surface on the electronic component, respectively. 7 and 8 can be moved by the reciprocating movement of the carriage 14 at the same time. In addition, a plurality of nozzles (not shown) for ejecting ink as droplets are respectively provided below the recording heads 5, 6, 7, and 8. Each nozzle discharges 2 pl to 30 pl for each ejection. Ink is ejected. It should be noted that the amount of liquid droplets ejected from each nozzle per ejection may be from 2 pl to 30 pl, and the amount of liquid droplets larger than that may be ejected.

  Note that the recording heads 7 and 8 in FIG. 1 are preliminary recording heads when further necessary functions are provided, and the recording heads are not limited to four as shown in FIG.

  Further, two ultraviolet irradiation devices 9 and 10 for irradiating ultraviolet rays are respectively mounted on the left and right sides of the carriage 14. The ultraviolet irradiation devices 9 and 10 are also mounted on the carriage 14 in the same manner as the recording heads 5, 6, 7, and 8. It is possible to move by reciprocating movement. Each ultraviolet irradiation device 9, 10 is provided with an ultraviolet light source 9 a, 10 a (shown in FIG. 3), and each ultraviolet irradiation device 9, 10 is mounted on an electronic component by turning on the ultraviolet light source 9 a, 10 a. Each recording surface can be irradiated with ultraviolet rays. As the ultraviolet light source, a high-pressure mercury lamp, a metal halide lamp, black light, a hot cathode tube, a cold cathode tube, an LED (Light Emitting Diode), or the like is applied.

  In the present embodiment, the ink discharge speed, carriage movement speed, etc. are adjusted, and after the ultraviolet curable ink discharged from the recording heads 5, 6, 7, 8 has landed on the electronic component 4, 1 Within seconds, the ink is irradiated with ultraviolet rays from the ultraviolet irradiation devices 9 and 10.

  The electronic component 4 is a general electronic component and represents an electronic component in which an electronic component element such as a bare chip or a chip capacitor is arranged on a circuit board.

  Next, the control part in the sealing material formation apparatus 1 is demonstrated with reference to FIG. FIG. 3 is a block diagram showing a schematic control configuration of the sealing material forming apparatus 1.

  As shown in FIG. 3, the sealing material forming apparatus 1 is provided with a control unit 30 that controls each driving unit. The control unit 30 includes an electronic component position detection 11, an ink heater 21 (means for heating ink), a transport mechanism 3 ′ of the electronic component 4, recording heads 5, 6, 7, 8, and ultraviolet rays of the ultraviolet irradiation devices 9, 10. Input for inputting instructions at the time of sealing formation, such as the light sources 10a and 10b, the carriage drive mechanism 22 of the carriage 14, the storage unit 31 for storing information necessary for the operation of the sealing material forming apparatus 1, and the type of the electronic component 4. The part 32 and the like are electrically connected. In addition to the above, each drive unit of the sealing material forming apparatus 1 is connected to the control unit 30.

  And by such a structure, the control part 30 is the position information of each electronic component obtained by the electronic component position detection 11, the position of the sealing formation material from the input part 32, the material kind used, ink temperature, etc. On the basis of these instructions, various devices are controlled in accordance with a control program and control data written in the storage unit 31.

  In particular, the control unit 30 adjusts the pressure and the ink temperature in the recording heads 5, 6, 7, 8, etc. Control is performed so that the droplet volume is 2 pl to 30 pl per discharge.

  Further, the amount of sealing material on the electronic component 4 is controlled by adjusting the moving speed of the carriage 14, the ink ejection timing, and the like.

  Further, the ink ejection speed, carriage movement speed, and the like are adjusted, and control is performed so that ultraviolet rays are irradiated from the ultraviolet irradiation devices 9 and 10 to the ink landing location within one second after the ink has landed on the electronic component 4. is doing.

Next, operation | movement of the sealing material formation apparatus 1 in this Embodiment is demonstrated.
First, when an instruction at the time of sealing formation such as the type of electronic component 4 in the sealing material forming apparatus 1 is input from the input unit 32, the control unit 30 extracts information necessary for image formation from the storage unit 31. Then, the sealing forming operation in the sealing material forming apparatus 1 is performed.

  During the sealing forming operation of the sealing material forming apparatus 1, while the electronic component position information is detected, the transport rollers 3 a and 3 b are operated and rotated, so that the electronic component 4 has a sealing formation surface by the platen 2. It is conveyed along the conveyance direction A from the rear to the front in the state of being an upper surface. On the other hand, the carriage 14 is actuated to reciprocate along the scanning direction B directly above the electronic component, and the four recording heads 5, 6, 7, 8 and the two ultraviolet irradiation devices 9, mounted on the carriage 14, 10 also moves by the reciprocating movement of the carriage 14.

  During the movement of the carriage 14, the four recording heads 5, 6, 7, and 8 eject ink from the nozzles toward the recording surface of the electronic component 4, and the two ultraviolet irradiation devices 9 and 10 are electronic components. 4 is irradiated with ultraviolet rays toward the recording surface. In particular, while the carriage 14 is moving from left to right in FIG. 1, the ultraviolet light source 9a of the left ultraviolet irradiation device 9 is turned on, and the carriage 14 is moved from right to left in FIG. During the operation, the ultraviolet light source 10a of the ultraviolet irradiation device 10 is turned on. That is, the ultraviolet light source 9a of the ultraviolet irradiation device 9 or the ultraviolet light source 10a of the ultraviolet irradiation device 10 on the downstream side of the recording heads 5, 6, 7 and 8 in the moving direction of the carriage 11 is turned on to irradiate ultraviolet rays.

Further, by controlling the control unit 30, the pressure in the recording heads 5, 6, 7, 8, the moving speed of the carriage 11, the ink discharge timing, and the like are changed to change each of the recording heads 5, 6, 7, 8. The minimum droplet amount of ink ejected from the nozzle is set to 2 pl to 30 pl per ejection, and controls the amount of sealing material on the electronic component 4. By adjusting the carriage moving speed and the like, the ultraviolet irradiation devices 9 and 10 are configured to irradiate ultraviolet rays on the corresponding portion within one second after the ink has landed on the electronic component 4. As a result, the ink ejected from each of the recording heads 5, 6, 7, 8 is irradiated with ultraviolet rays immediately after landing on the electronic component 4, is immediately cured, and is fixed on the recording surface of the electronic component 4.

  Thereafter, the sealing material forming apparatus 1 repeats each of the above-described operations, selects each ink-jet ink with a desired ink amount and type consisting of one dot or a plurality of dots, and sequentially records them on the recording surface of the electronic component 4. Thereafter, the electronic component 4 is transported by a transport device and discharged to a discharge tray (not shown).

  In this embodiment, the serial type sealing material forming apparatus is described. However, the present invention is not limited to this, and can be applied to, for example, a line type sealing material forming apparatus. is there.

  FIG. 4 is a front view showing an example of the configuration of the main part used in the serial printing method in the sealing material forming apparatus 1 (with built-in electronic component heater) that can be used in the present invention. FIG. 5 is a side view of the apparatus.

  The sealing material forming apparatus 1 includes an electronic component position detector 11, an electronic component non-contact thermometer 13, a transport member 99 that transports the sealing surface of the electronic component 4 upward, a head carriage 14, recording heads 5, 6, and 6. 7 and 8, light irradiation means 9 and 10, and a flat platen part (built-in heater: means for heating electronic components) 2. Before and after the platen 2, conveying rollers 3a and 3b are disposed as a conveying mechanism. Each of the transport rollers 3a and 3b is rotated in a predetermined direction around the axis before and after the platen 2, and the transport member 99 is moved along the transport direction A along with the rotation of the transport rollers 3a and 3b. Is supposed to be transported. In the present invention, the electronic component 4 and the conveying member 99 are separately configured. However, in order to improve the conveying accuracy, a base material in which the conveying member and the electronic component are integrated may be used.

  Although the heating amount for the electronic component 4 by the flat platen part (with built-in heater) 2 is adjusted, the method for adjusting the heating amount is not limited to this. For example, the applied voltage to the flat platen part (with built-in heater) 2 or The applied voltage width may be changed. Further, the flat platen portion (with built-in heater) 2 may be a function of only the heat plate. You may make it use the warm air apparatus which blows a far infrared ray and warm air for a heater.

  In the present embodiment, the heating amount for the electronic component 4 by the heater 11 is adjusted according to the environmental humidity. However, the heating amount may be adjusted according to the environmental temperature.

  As shown in FIG. 4, the sealing material forming apparatus 1 has a rod-shaped guide rail 12, and a carriage 14 is supported on the guide rail 12. The carriage 14 reciprocates along the guide rail 12 in the scanning direction B by a carriage drive mechanism 22 (see FIG. 5).

  Mounted on the carriage 14 are four recording heads 5, 6, 7, and 8 for ejecting the ink-jet ink according to the present invention toward the recording surface on the electronic component, respectively. 7 and 8 can be moved by the reciprocating movement of the carriage 14 at the same time. In addition, a plurality of nozzles (not shown) for ejecting ink as droplets are respectively provided below the recording heads 5, 6, 7, and 8. Each nozzle discharges 2 pl to 30 pl for each ejection. Ink is ejected. It should be noted that the amount of liquid droplets ejected from each nozzle per ejection may be from 2 pl to 30 pl, and the amount of liquid droplets larger than that may be ejected.

  Note that the recording heads 7 and 8 in FIG. 4 are preliminary recording heads when further necessary functions are provided, and the recording heads are not limited to four as shown in FIG.

  Further, two ultraviolet irradiation devices 9 and 10 for irradiating ultraviolet rays are respectively mounted on the left and right sides of the carriage 14. The ultraviolet irradiation devices 9 and 10 are also mounted on the carriage 14 in the same manner as the recording heads 5, 6, 7, and 8. It is possible to move by reciprocating movement. Each ultraviolet irradiation device 9, 10 is provided with an ultraviolet light source 9a, 10a (shown in FIG. 6), and each ultraviolet irradiation device 9, 10 is mounted on an electronic component by turning on the ultraviolet light source 9a, 10a. Each recording surface can be irradiated with ultraviolet rays. As the ultraviolet light source, a high-pressure mercury lamp, a metal halide lamp, black light, a hot cathode tube, a cold cathode tube, an LED (Light Emitting Diode), or the like is applied.

  In the present embodiment, the ink discharge speed, carriage movement speed, etc. are adjusted, and after the ultraviolet curable ink discharged from the recording heads 5, 6, 7, 8 has landed on the electronic component 4, 1 Within seconds, the ink is irradiated with ultraviolet rays from the ultraviolet irradiation devices 9 and 10.

  The electronic component 4 is a general electronic component and represents an electronic component in which an electronic component element such as a bare chip or a chip capacitor is arranged on a circuit board.

  Next, the control unit in the sealing material forming apparatus 1 will be described with reference to FIG. FIG. 6 is a block diagram showing a schematic control configuration of the sealing material forming apparatus 1.

  As shown in FIG. 6, the sealing material forming apparatus 1 is provided with a control unit 30 that controls each driving unit. The control unit 30 includes an electronic component position detection 11, an electronic component non-contact thermometer 13, an ink heater 21, a transport mechanism 3 ′ of the electronic component 4, recording heads 5, 6, 7, and 8, and ultraviolet irradiation devices 9 and 10. UV light sources 10a and 10b, carriage drive mechanism 22 of carriage 14, storage unit 31 for storing information necessary for the operation of sealing material forming apparatus 1, and instructions at the time of sealing formation such as the type of electronic component 4 are input. The input unit 32 and the like are electrically connected. In addition to the above, each drive unit of the sealing material forming apparatus 1 is connected to the control unit 30.

  With such a configuration, the control unit 30 allows the position information of each electronic component obtained by the electronic component position detection 11, the information obtained by the electronic component temperature detection 13, the position information of each electronic component, and the input unit 32. Various devices are controlled according to the control program and control data written in the storage unit 31 based on the position of the seal forming material, the type of material used, the ink temperature, and the like.

  In particular, the control unit 30 includes a temperature control mechanism (which controls the temperature of the ink for each recording head) in which the pressure, the ink temperature, and the electronic component temperature in the recording heads 5, 6, 7, and 8 are incorporated in the conveying member 2 and the ink carriage. The minimum droplet amount of ink ejected from each nozzle of the recording heads 5, 6, 7 and 8 is adjusted by means of control means, means for controlling the temperature of electronic components, etc.) Control is performed to be 2 pl to 30 pl.

  Further, the amount of sealing material on the electronic component 4 is controlled by adjusting the moving speed of the carriage 14, the ink ejection timing, and the like.

  Further, the ink ejection speed, carriage movement speed, and the like are adjusted, and control is performed so that ultraviolet rays are irradiated from the ultraviolet irradiation devices 9 and 10 to the ink landing location within one second after the ink has landed on the electronic component 4. is doing.

  Next, the operation of the sealing material forming apparatus 1 (built-in electronic component heater) in the present embodiment will be described.

  First, when an instruction at the time of sealing formation such as the type of electronic component 4 in the sealing material forming apparatus 1 is input from the input unit 32, the control unit 30 extracts information necessary for image formation from the storage unit 31. Then, the sealing forming operation in the sealing material forming apparatus 1 is performed.

  During the sealing forming operation of the sealing material forming apparatus 1, the electronic roller 4 is operated and rotated while detecting the electronic component position information and further controlling the temperature of the electronic component. The platen 2 is transported along the transport direction A from the rear to the front with the sealing formation surface being the top surface. On the other hand, the carriage 14 is actuated to reciprocate along the scanning direction B directly above the electronic component, and the four recording heads 5, 6, 7, 8 and the two ultraviolet irradiation devices 9, mounted on the carriage 14, 10 also moves by the reciprocating movement of the carriage 14.

  During the movement of the carriage 14, the four recording heads 5, 6, 7, and 8 eject ink from the nozzles toward the recording surface of the electronic component 4, and the two ultraviolet irradiation devices 9 and 10 are electronic components. 4 is irradiated with ultraviolet rays toward the recording surface. In particular, while the carriage 14 is moving from left to right in FIG. 1, the ultraviolet light source 9a of the left ultraviolet irradiation device 9 is turned on, and the carriage 14 is moved from right to left in FIG. During the operation, the ultraviolet light source 10a of the ultraviolet irradiation device 10 is turned on. That is, the ultraviolet light source 9a of the ultraviolet irradiation device 9 or the ultraviolet light source 10a of the ultraviolet irradiation device 10 on the downstream side of the recording heads 5, 6, 7 and 8 in the moving direction of the carriage 11 is turned on to irradiate ultraviolet rays.

Further, by controlling the control unit 30, the pressure in the recording heads 5, 6, 7, 8, the moving speed of the carriage 11, the ink discharge timing, and the like are changed to change each of the recording heads 5, 6, 7, 8. The minimum droplet amount of ink ejected from the nozzle is set to 2 pl to 30 pl per ejection, and controls the amount of sealing material on the electronic component 4. By adjusting the carriage moving speed and the like, the ultraviolet irradiation devices 9 and 10 are configured to irradiate ultraviolet rays on the corresponding portion within one second after the ink has landed on the electronic component 4. As a result, the ink ejected from each of the recording heads 5, 6, 7, 8 is irradiated with ultraviolet rays immediately after landing on the electronic component 4, is immediately cured, and is fixed on the recording surface of the electronic component 4.

  Thereafter, the sealing material forming apparatus 1 repeats each of the above-described operations, selects each ink-jet ink with a desired ink amount and type consisting of one dot or a plurality of dots, and sequentially records them on the recording surface of the electronic component 4. Thereafter, the electronic component 4 is transported by a transport device and discharged to a discharge tray (not shown).

  In this embodiment, the serial type sealing material forming apparatus is described. However, the present invention is not limited to this, and can be applied to, for example, a line type sealing material forming apparatus. is there.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

  The following experiments were conducted using various inks containing the photopolymerizable compounds shown in Table 1. When the ink was a mixture of photopolymerizable compounds, it was put in a stainless beaker, stirred and mixed for 1 hour while being heated on a hot plate at 40 ° C., and dissolved.

"Encapsulant formation method"
Each of the ink sets 1 to 7 prepared above was loaded into a sealing material forming apparatus shown in FIGS. 1 and 4 equipped with a piezo-type inkjet nozzle and sealed. The ink supply system was composed of an ink tank, a supply pipe, a front chamber ink tank immediately before the head, a pipe with a filter, and a piezo head. The ink was insulated from the front chamber tank to the head portion and heated at 50 ° C. The piezo head was driven so that 2 to 30 pl multi-size dots could be ejected, and each ink was ejected continuously. After landing, it was cured instantaneously (less than 0.5 seconds after landing) with a metal halide lamp (MAL400NL 3 kW power source manufactured by Nippon Battery Co., Ltd.) on both sides of the carriage. After recording, the total ink film thickness was measured and found to be in the range of 2.0 to 20 μm.

  As shown in Table 2, when the sealing material forming apparatus of FIG. 4 was used, the electronic material temperature was kept at 40 ° C. to form the sealing material.

  Table 1 summarizes the contents of the inkjet ink and the tensile modulus and water absorption rate of the cured product (resin). In addition, the tensile elasticity modulus of hardened | cured material is a measured value obtained by the measurement based on a "JISK7127" test method. Further, the water absorption is a measured value obtained by measurement based on the “JIS K 6911” test method. The numerical value which shows the addition amount of the compounds 1-7 described in Table 1 represents the mass%.

<< Evaluation of inkjet sealing material >>
The electronic component shown in FIG. 7 was sealed with inkjet ink, and the following evaluations were performed.

<Moisture resistance>
After the finished electronic component was stored in a 40 ° C./80% environment for 3 days, the electrical conductivity of the electronic component was evaluated. Evaluation evaluated n50.
×: Not functioning 50% or more Δ ×: Deteriorating function with 50% frequency Δ; Degrading function with 30% frequency ○ Δ; Degrading function with 10% frequency ○: No change

<Impact resistance (sealing position reliability) evaluation>
The finished electronic component was firmly fixed, and a weight (S45C steel) having a tip diameter of 20 mm and a weight of 50 g was freely dropped onto the electronic component connecting portion from the height of 10 cm onto the electronic component connecting portion at the center of the cradle. The conductivity was confirmed after the test. Evaluation evaluated n50.
×: Not functioning 50% or more Δ ×: Deteriorating function with 50% frequency Δ; Degrading function with 30% frequency ○ Δ; Degrading function with 10% frequency ○: No change

  The evaluation results are shown in Table 2.

  As is clear from the results shown in Table 2, it can be seen that the sealing material formed using the ink according to the present invention is excellent in moisture resistance and impact resistance.

  In consideration of the above-described method of forming the sealing material and the description of the apparatus, the present invention provides a sealing material and electronic component sealing excellent in impact resistance, moisture resistance, etc., and excellent in productivity. It can be seen that the material can be provided. Moreover, it turns out that the formation method and formation apparatus of the said sealing material can be provided.

The front view which shows an example of a structure of the principal part of a sealing material formation apparatus (no electronic component heater) Side view showing an example of a configuration of a main part of a sealing material forming apparatus (without an electronic component heater) Block conceptual diagram showing control configuration of sealing material forming device (without electronic component heater) The front view which shows an example of a structure of the principal part of the sealing material formation apparatus (built-in electronic component heater) Side view showing an example of the configuration of the main part of a sealing material forming apparatus (with built-in electronic component heater) Block conceptual diagram showing control configuration of sealing material forming device (built-in electronic component heater) Figure showing an example of electronic components Sectional view showing double structure of encapsulant

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Sealing material formation apparatus 2 Platen 3a, 3b Conveyance roller 4 Electronic component 5, 6, 7, 8 Recording head 9 Irradiation means 10 Ultraviolet light source 11 Electronic component position detector 12 Guide rail 13 Non-contact thermometer 14 for electronic components 14 Carriage DESCRIPTION OF SYMBOLS 30 Control part 21 Ink heater 22 Carriage drive mechanism 31 Memory | storage part 32 Input part 99 Conveyance member

Claims (8)

A sealing material comprising a cured product formed by curing at least two kinds of compositions containing a photopolymerizable compound, and the cured product after the first composition is cured has a tensile modulus of 1 Sealing comprising: a first resin cured portion of ˜500 MPa; and a second resin cured portion having a water absorption of 0 to 1% after cured of the second composition Wood. The sealing material according to claim 1, wherein the sealing material is used as a sealing material for electronic components. The sealing material according to claim 1 or 2, wherein the at least two kinds of compositions containing the photopolymerizable compound are at least two kinds of inkjet inks. It is a formation method of the sealing material as described in any one of Claims 1-3, Comprising: A sealing material is formed with an inkjet system, The formation method of the sealing material characterized by the above-mentioned. The ink for forming the sealing material and the temperature of the ink jet recording head are heated to 35 to 100 ° C., and then the ink is discharged and cured to form the sealing material. Forming method of sealing material. 6. The method for forming a sealing material according to claim 4, wherein after the ink has landed on the object to be sealed, the ink is irradiated with light and cured to form the sealing material. A sealing material forming apparatus for use in the sealing material forming method according to any one of claims 4 to 6, wherein the light irradiation means, the means for measuring the ink temperature, the means for heating the ink, and each recording head A sealing material forming apparatus comprising: means for controlling the temperature of the ink; means for detecting position information of the electronic component; and means for controlling ink ejection from the recording head according to the position information. . 8. The sealing material forming apparatus according to claim 7, comprising means for heating the electronic component and means for controlling the temperature of the electronic component.

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