WO2006118176A1 - Polyimide for optical component, optical component and optical waveguide - Google Patents

Abstract

This invention provides a polyimide having very low transmission loss, an optical component, and an optical waveguide. The polyimide for an optical component is characterized in that it comprise at least diamines containing a diamine having a fluorine substituent and a fluorenyl group, and tetracarboxylic acid dianhydrides and the transmission loss at a wavelength of 830 nm is not more than 1 dB/cm in both TE mode and TM mode.

Description

 Specification

 Polyimide for optical components, optical components and optical waveguides

 Technical field

 The present invention relates to a polyimide for producing an optical component used in the fields of optical communication and optical information processing, and an optical component and an optical waveguide produced using the resin. Background art

 [0002] In the multimedia era, transmission systems that use light as a transmission medium have been developed in response to demands for large-capacity and high-speed information processing in optical communication systems and computers. FTTH (Fibre To The Home), LAN (Local Area Network), FA (Factory Automation), Interconnects in computer boards, Interconnects between computers, Home wiring, etc. Among the elements that make up this transmission system, optical waveguides are, for example, optical devices (ONU (Optical Network Unit), etc.), photoelectric integrated circuits for realizing large-capacity information transmission such as movies and movies and optical computers. (OEIC), basic components in optical integrated circuits (optical IC), etc. In particular, optical waveguides have been studied earnestly due to the large amount of demand, while high-performance and low-cost products are required. Conventionally known optical waveguides include quartz optical waveguides and polymer optical waveguides.

[0003] Among these, the silica-based optical waveguide has an advantage that the transmission loss is low, but there are process problems such as high processing temperature in the manufacturing process and difficulty in manufacturing a large-area one. It was. In addition, polymer-based optical waveguides have advantages such as ease of processing and wide material design, and therefore, those using polymer materials such as polymethylmethalate and polycarbonate have been studied. However, the polymer-based optical waveguide has a problem that heat resistance is poor. In addition, polymethylmetatalate and polycarbonate have had a problem of large transmission loss at a wavelength of about 830 nm, which has recently been studied as a light source for optical communication. For this reason, recently, fluorinated polyimide has been actively used as a polymer for optical waveguides because it has excellent properties such as heat resistance and excellent transmission loss. [0004] For example, Patent Document 1 proposes a fluorinated polyimide that defines a refractive index difference between a TE mode and a TM mode, a glass transition temperature, a transmission loss in a certain wavelength region, and a fluorine content. However, there is no description about polyimide having a fluorene skeleton. Patent Document 1: Japanese Patent Laid-Open No. 2003-41003

 Disclosure of the invention

 Problems to be solved by the invention

[0005] As described above, the conventional polymer-based optical waveguide material is a transmission loss of the waveguide in a region of 600 to 1600 nm (particularly around 830 nm, which has been recently studied) used in optical communications and the like. There is a problem that is not relatively large and small enough, and it does not satisfy the various characteristics required for optical waveguides. Even if transmission loss is satisfied, it is relatively limited in terms of material selection. Accordingly, an object of the present invention is to provide a polyimide, an optical component, and an optical waveguide with extremely low transmission loss.

 Means for solving the problem

[0006] As a result of intensive studies to solve the above problems, the present inventor has found that a polyimide using a diamine having a fluorine substituent and a fluorenyl group has a specifically low transmission loss at a wavelength of 830 nm. The present invention has been completed.

[0007] A first aspect of the present invention is a polyimide comprising a diamine containing diamine having at least a fluorine substituent and a fluorenyl group, and a tetracarboxylic dianhydride having a wavelength of 8

Polyimide for optical components, characterized in that transmission loss at 30nm is ldBZcm or less in both TE mode and TM mode.

[0008] A second aspect of the present invention is the polyimide for optical components according to the first aspect, wherein the transmission loss at a wavelength of 633 nm is 1 dBZcm or less in both the TE mode and the TM mode. .

 [0009] In a third aspect of the present invention, the diamino amino group having a fluorine substituent and a fluorenyl group is bonded to an aromatic ring, and the fluorine substituent is located at the ortho position of the amino group. The polyimide for optical parts according to the first or second invention, wherein the polyimide is for optical parts.

[0010] A fourth aspect of the present invention is a diamine force having the above-described fluorine substituent and fluorenyl group. The polyimide for optical parts according to the first or second invention, which is a diamine represented by the formula (1).

 [0011] [Chemical 1]

[0012] (wherein R to R may be the same or different, either hydrogen or fluorine.

 1 8

 And at least one is fluorine. )

 According to a fifth aspect of the present invention, the diamine having a fluorine substituent and a fluorenyl group is 9,9-bis (3-fluoro-4-aminophenol) fluorene. It is a polyimide for optical components described in the invention.

 [0013] In a sixth aspect of the present invention, the diamine includes the diamine having a fluorine substituent and a fluorenyl group and one or more types of copolymerization diamine, wherein the copolymerization diamine is represented by the following formula (2): The polyimide for optical components according to any one of the first to fifth inventions, wherein the polyimide is an diamine represented by formula (1).

 [0014] [Chemical 2]

[0015] (In the formula, any two of X to 式 are 、, and the remaining 8 are from H, CH and CF.

 1 10 2 3 3 is any one group selected from the group consisting of R is -Ο-, -S-, -SO-,

 11 2

-CH-, -CO-, -C (CH) ―, -C (CF) ―, -O -R — O, one fluoride

2 3 2 3 2 12

 -Lu group- and direct bond force are group forces. Where R

12 is an alkyl group having 1 or more and 5 or less carbon atoms, and a group force which is selected as a group force represented by the following formula group (3). [0016] [Chemical 3]

[0017] According to a seventh aspect of the present invention, the copolymerization diamine is 4,4'-diaminodiphenyl ether, 3,4, -diaminodiphenyl ether, 2,2, -bis (trifluoromethyl) -4, 4, -Diaminobiphenyl, 4, 4, -Diaminodiphenyl sulfone, 1,5- (4-aminophenoxy) pentane, 1,3-bis (4-aminophenoxy) -2,2-dimethylpropane, 2,2-bis ( 4-aminophenoloxy) propane, 2,2-bis [4- (4-aminophenoxy) phenol] hexafluoropropane, bis [4- (4-aminophenoxy) phenol] sulfone And the bis [4- (3-aminophenoxy) phenyl] sulfone force, and the at least one diamine selected for the group force, the polyimide for optical components according to the sixth invention.

 [0018] According to an eighth aspect of the present invention, in any one of the first to seventh aspects, the tetracarboxylic dianhydride includes a tetracarboxylic dianhydride having a fluorine substituent. It is a polyimide for optical parts.

 [0019] In a ninth aspect of the present invention, the tetracarboxylic dianhydride includes 2,2-bis-((3,4-dicarboxyphenyl) monohexafluoropropane dianhydride). The polyimide for optical parts according to any one of the first to seventh inventions, wherein the polyimide is for optical parts.

 [0020] According to a tenth aspect of the present invention, the tetracarboxylic dianhydrides include 2,2-bis-((3,4-dicarboxyphenyl) monohexafluoropropane dianhydride) and Including one or more types of copolymerization tetracarboxylic dianhydrides, wherein the copolymerization tetracarboxylic dianhydride is a tetracarboxylic dianhydride represented by the following formula (4): The polyimide for optical components according to any one of the first to seventh inventions.

[0021] [Chemical 4] Formula (4)

[0022] (In the formula, R is — O—, —CO—, —SO— and a group force consisting of direct bonding force

 13 2

 One of them. )

 In an eleventh aspect of the present invention, the transmission loss at the wavelength of 830 nm is 0.1 dB / cm or less in both the TE mode and the TM mode. It is a polyimide for optical parts.

 [0023] In a twelfth aspect of the present invention, the transmission loss at the wavelength of 633nm is 0.1 dB / cm or less in both the TE mode and the TM mode. It is a polyimide for optical components as described in above.

 A thirteenth aspect of the present invention is characterized in that the refractive index at a wavelength of 830 nm is 1.55 or more for both the TE mode and the TM mode, and the difference in refractive index between the TE mode and the TM mode is 0.01 or less. The polyimide for optical components according to any one of the first to twelfth inventions.

 A fourteenth aspect of the present invention is characterized in that the refractive index at a wavelength of 633 nm is 1.55 or more for both the TE mode and the TM mode, and the difference in refractive index between the TE mode and the TM mode is 0.01 or less. The polyimide for optical components according to any one of the first to twelfth inventions.

 [0026] The fifteenth aspect of the present invention is capable of bending 300 times or more in the MIT bending test with a bending radius of 0.38 mm, a bending angle of 135 °, and a load of lOOg when a film having a thickness of 50 m is formed. The polyimide for optical parts according to any one of the first to fourteenth inventions.

 [0027] The sixteenth aspect of the present invention is a group force consisting of dioxolane, dimethylformamide, N-methyl-2-pyrrolidone, N, N dimethylacetamide and methylethylketone, at least one single solvent or two or more selected The polyimide for optical components according to any one of the first to fifteenth inventions, which has a solubility power of 20% by weight or more in a mixed solvent at 25 ° C.

[0028] A seventeenth aspect of the present invention is a polyimide for optical components according to any one of the first to sixteenth aspects of the present invention. It is a polyamic acid which is a precursor of

 [0029] An eighteenth aspect of the present invention is an optical component comprising the polyimide according to any one of the first to sixteenth aspects and Z or the polyamic acid according to the seventeenth aspect.

 [0030] A nineteenth aspect of the present invention is an optical waveguide comprising the polyimide according to any one of the first to sixteenth aspects and Z or the polyamic acid according to the seventeenth aspect.

 [0031] According to the twentieth aspect of the present invention, in an optical waveguide having a core and a clad, a polyimide comprising at least a diamine containing diamine having a fluorine substituent and a fluorenyl group and a tetracarboxylic dianhydride is used as a core. This is an optical waveguide.

 [0032] The twenty-first aspect of the present invention is the optical waveguide according to the twentieth aspect, wherein the transmission loss of the optical waveguide at a wavelength of 830 nm is ldBZcm or less in both the TE mode and the TM mode.

 [0033] A twenty-second aspect of the present invention is the optical waveguide according to the twentieth or twenty-first aspect of the present invention, wherein the transmission loss of the optical waveguide at a wavelength of 633 nm is ldB / cm or less in both the TE mode and the TM mode. is there.

 The invention's effect

 [0034] The polyimide of the present invention has physical properties such as excellent transmission characteristics (low! Waveguide transmission loss) when optical components and optical waveguides with extremely low transmission loss at 830 nm are formed. It can be suitably used as an optical component and an optical waveguide forming material. In addition, the transmission loss at 633 nm is extremely low.

 BEST MODE FOR CARRYING OUT THE INVENTION

 [0035] Hereinafter, the present invention will be described in detail.

 [0036] <Optical components / optical waveguide>

The optical component of the present invention includes an optical branching coupler (optical power bra), an optical multiplexer / demultiplexer, an optical isolator, a ring power plastic, a grating (diffraction grating), a lens array, a Furnell lens, a micromirror, a mode converter or Photonic crystals, optical waveguides, etc. For example, in the case of grating, it is used as a wavelength filter in optical communications, and also used as a pickup in a CD optical system. Lens arrays are also used in various applications such as liquid crystal projectors. <Optical component manufacturing method> Optical waveguide manufacturing method>

 The optical component manufacturing method may follow a conventional optical component manufacturing method using a polymer. For example, an example of a method for manufacturing an optical waveguide will be described. When using the polyimide for optical parts of the present invention for an optical waveguide core, first, polyimide having a low refractive index is selected from the polyimide for optical parts of the present invention and used as a cladding material. The cladding layer is formed on a silicon substrate or the like by spin coating or vacuum deposition. The optical waveguide core is formed by spin coating the polyimide for optical components of the present invention, which is a core material, on the cladding layer, and then performing resist coating, patterning, etching, etc. Only the core is formed. Next, the upper clad is fabricated by spin coating.

 [0038] As another method for producing an optical waveguide, an ultrashort pulse laser (pulse laser on the order of 10 femtoseconds or more and 500 picoseconds or less) is condensed and irradiated inside a polyimide film, and the polyimide film is scanned. There is a method of forming an optical waveguide by scanning an ultrashort pulse laser.

 [0039] In addition, there are a method of forming an optical waveguide by electron beam (EB) irradiation, a method of patterning a core or a clad by exposure using photosensitive polyimide, and the like. Further, a fluorinated polyamic acid solution spin coat is formed from a transfer mold in which a silicon oxide film is deposited on a polyimide transfer mold or a quartz glass transfer mold, and is heated and imidized. After dipping in an acid aqueous solution (for polyimide transfer mold) or water (for quartz transfer mold) to release the transfer mold force, the groove formed by spin-coating the polyamic acid solution that becomes the optical waveguide core is filled, There is a method in which an optical waveguide is formed by heating imidization and forming an upper clad with the same molding material as that of a clad formed by a transfer mold on the upper part.

 [0040] Sarakuko is a method in which a core material is dissolved in an organic solvent, the solution is applied by ink jet to form a core portion, and then an upper cladding layer is formed to form an optical waveguide. There is a self-forming method in which the monomer solution that becomes the polymer is guided and irradiated with ultraviolet rays from one optical fiber, and the irradiated part gradually extends to form the core part.

 [0041] <Transmission loss of polyimide>

The polyimide for optical components in the present invention at a wavelength of 830 nm and a wavelength of 633 nm The transmission loss is ldBZcm or less in both TE mode and TM mode, preferably 0.5 dB / cm or less, and more preferably 0.1 dBZcm or less. If the transmission loss is greater than ldBZcm, the power consumption of the light source input to the optical component will increase.

 The transmission loss of the polyimide for optical parts in the present invention is preferably not more than the wavelength 830 nm and the wavelength 633 nm, but the transmission loss in the wavelength region of 600 nm to less than lOOOnm and Z or lOOOnm is ldBZcm or less. This is because two-way communication using many types of wavelengths is possible if the transmission loss is less than ldBZcm even in wavelength ranges other than 830 nm and 633 nm.

 [0043] The transmission loss of polyimide in the present invention was measured using a prism force plastic model 2010 (manufactured by Metricon), which is an apparatus that can realize the prism force bra method. Regarding the measurement mode, since the polarization of the transmitted light is usually performed separately from the TE mode and the TM mode, the transmission loss was measured in both of the embodiments of the present invention.

 [0044] The transmission loss measured by the prism force bra method is the wavelength guided through a thin film with a thickness of about 1 μm to 15 m fabricated on a silicon substrate with an oxide film by a spin coat method. The slope of the straight line obtained by plotting the change in leakage light intensity and transmission length of light at 830 nm and 633 nm is calculated. This method can be applied in a thin film having a thickness of 1 m or more and 15 m or less. In this thickness range, the transmission loss does not depend on the thickness, but as the thickness increases, many transmission modes exist and measurement becomes difficult. On the other hand, if it is thicker than 15 m, the smoothness of the thin film is impaired, which is not preferable. If it is less than 1 μm, there is no transmission mode and measurement is not possible.

[0045] It should be noted that the TE mode, TM mode, and difference in refractive index between the TE mode and TM mode of the present invention are used in the same meaning as those known to those skilled in the art (for example, (Patent Document 1) 2003-41003).

[0046] <Transmission loss of optical waveguide>

 The transmission loss of the optical waveguide made of the polyimide of the present invention at a wavelength of 830 nm and a wavelength of 633 nm is less than ldBZcm in both TE mode and TM mode, preferably 0.5d.

BZcm or less, more preferably 0.1 dBZcm or less. [0047] Generally, when polyimide for an optical component is actually applied to an optical component such as an optical waveguide, the transmission loss of the optical component is larger than the transmission loss of the optical component polyimide itself as a raw material. This is because when the polyimide is added to the desired state by the above-described method, there are a few scratches and undulations at the interface, and losses are caused by scattering from the interface. Therefore, when the transmission loss in an optical component (for example, an optical waveguide) is less than ldBZcm, it is used to manufacture the optical component! The transmission loss of the optical component polyimide is less than 1 dBZcm. It will be natural.

 [0048] <Refractive index>

 The refractive index in the present invention is a value obtained by measuring by the prism force bra method. The prism force plastic model 2010 (made by Metricon) was used for the measurement.

 In the present invention, the refractive index at a wavelength of 830 nm and a wavelength of 633 nm is preferably 1.55 or more in both the TE mode and the TM mode. If the refractive index is less than 1.55, the combination with other resins is limited when using the difference in refractive index when used for optical parts. In particular, when the polyimide of the present invention is used for the core of the optical waveguide, it is necessary to select a material having a refractive index smaller than that of the core as the cladding material. If the refractive index is less than 1.55, the choice of cladding material is limited.

 The refractive index difference in the present invention is a value obtained by subtracting the refractive index power in the plane direction and the refractive index in the thickness direction. The refractive index in the surface direction represents the refractive index obtained when measured using TE mode light, and the refractive index in the thickness direction represents the refractive index obtained when measured using TM mode light. Represents. When used as an optical waveguide material, the smaller the refractive index difference, the better. This is because if the difference in refractive index is large, the refractive index varies depending on the polarization direction of the light incident on the waveguide, so that differences in the propagation mode and propagation speed appear and the signal transmission accuracy may deteriorate.

 [0051] The refractive index difference in the present invention was measured by the prism force bra method. Specifically, Prism Force Plastic Model 2010 (made by Metricon) was used.

 [0052] <Polyimide using diamines including diamine having at least a fluorine substituent and a fluorenyl group and tetracarboxylic dianhydrides>

The polyimide of the present invention has at least a fluorine substituent and a fluorenyl group as a raw material. A polyimide comprising a diamine containing diamine and a tetracarboxylic dianhydride.

 [0053] <Diamins>

 An example of a diamine having a fluorine substituent and a fluorenyl group includes fluorenedamine having a structure represented by the following formula (1).

[0054] [Chemical 5]

[0055] (In the formula, R to R may be the same or different from each other, either hydrogen or fluorine.

 1 8

 And at least one is fluorine. )

 Specifically, 9, 9-bis (3-fluoro-4-aminophenol) fluorene, 9, 9-bis (3,3,1-difluoro-4-aminophenol) fluorene, 9, 9-bis (2 , 3-Difluorine 4-Faminophenol) Fluorene, 9, 9-Bis (2,2 ', 3-trifluoro-4-fluorophenyl) Fluoroamine containing one or more fluorine substituents such as fluorene Is exemplified.

 Among these, it is desirable that the amino group of diamine having a fluorine substituent and a fluorenyl group is bonded to an aromatic ring, and the fluorine substituent is located at the ortho position of the amino group. . This is because a spatial twist occurs in the fluorenedamine unit and the tetracarboxylic dianhydride unit, coloring due to charge transfer absorption is limited, and transmission loss is reduced.

 [0057] More preferably, the diamine is 9,9-bis (3-fluoro-4-aminophenol) fluorene. This is because the transmission loss becomes smaller.

 <Polyimide copolymerization>

One of the major merits of using a polymer for an optical material is bending resistance. For example, when an optical waveguide is mounted on a flexible substrate such as a mobile phone, the optical waveguide material In addition to transmission loss, the bending resistance of the material is also important as a characteristic required for the material. The present inventors consider that the factors governing the bending resistance are mainly the structure of the monomer and the arrangement order of the molecular chains. By controlling these, the bending resistance is improved compared to conventional polymers. Therefore, as a result of copolymerizing polyimide containing diamine having a flexible molecular structure to diamine having a fluorine substituent and a fluorenyl group, the transmission loss is relatively low, and the bending resistance is greatly improved while maintaining the value. I found this on my own.

 [0058] The polyimide copolymerized with the formula (1) is preferably a polyimide containing diamine having a structure represented by the following formula (2) from the viewpoint of enhancing flexibility.

[0059] [Chemical 6]

[0060] (Any two of X to X in the formula are NH, and the remaining eight are H, CH and CF forces.

 1 10 2 3 3 One force selected from the group consisting of one group. R

 11 is — O—, — S—, —SO—,

 2 CH —, one CO—, -C (CH) one, C (CF) —, -O-R O, one fluoride

2 3 2 3 2 12

 -Lu group- and direct bond force are group forces. Where R

 12 is an alkyl group having 1 or more and 5 or less carbon atoms, and a group force which is selected as a group force represented by the following formula group (3).

[0061] [Chemical 7]

[0062] Among them, 4, 4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 2,2'-bis (trifluoromethyl) -4,4'-diaminobiphenyl, 4 , 4'-Diaminodi Phenylsulfone, 1,5- (4-aminophenoxy) pentane, 1,3-bis (4-aminophenoxy) -2,2-dimethylpropane, 2,2-bis (4-aminophenoxyphenol) propane 2,2-bis [4- (4-aminophenoxy) phenol] hexafluoropropane, bis [4- (4-aminophenoxy) phenol] sulfone and bis [4- (3-aminophenoxy) It is preferable to copolymerize a polyimide containing at least one diamine selected from the group]

[0063] Therefore, the polyimide copolymer as described above is the most preferred form for applications requiring flexibility such as a flexible substrate. Of course, the number of diamines may be three or more as long as they contain a fluorine substituent and a fluorenyl group. Further, not limited to diamines, a copolymer using a plurality of tetracarboxylic dianhydrides may be produced.

 [0064] According to the monomer ratio of copolymerization, at least the diamine having a fluorine substituent and a fluorenyl group satisfies 30 mol% or more of the total diamine ratio! / If other diamine, tetracarboxylic dianhydride The ratio of things!

 [0065] Further, the structure of the polyimide used for the optical component requiring transparency is not particularly limited, but as the diamines used in the present invention, for example, the following may be used for copolymerization. However, jamins other than those described herein can also be used. In particular, a diamine skeleton containing an electron-withdrawing group such as SO--, -C (CF) 1, -CO, or

 2 3 2

 Those in which electron-withdrawing groups such as CF, F, Cl and Br are introduced directly into the aromatic ring of diamine are preferred.

 Three

Good. For example, 3, 3, 1-diaminodiphenyl sulfone, 3, 4, 1-diaminodiphenyl sulfone, 4, 4'-diaminodiphenyl sulfone, 3, 3'-diaminobenzophenone, 3, 4'-diaminobenzophenone, 4, 4'-aminominobenzofuenone, 2, 2 bis (4-aminominophenole) 1, 1, 1, 3, 3, 3 hexaf-noreolov. Ronon, 2, 2 and 3, Su (3 aminophene-nore) —1, 1, 1, 3, 3, 3 Hexafnoreolov. Ronon, 2— (3 aminophenol) 1— 2- (4-aminofluorine) 1, 1, 1, 3, 3, 3 Hexafnole-old lopronone, 1, 3 h, S (3 aminobenzoyl) ) Benzene, 1,4 bis (3-aminobenzoyl) benzene, 1,3 bis (4-aminobenzoyl) benzene, 1,4 bis (4-aminobenzoyl) benzene, 3, 3, 1 diamine Enoxybenzophenone, 4,4'-diamino-5-phenoxybenzophenone, 3, 4'-diamino-4 phenoxybenzophenone, 3, 4'-diamino-5-phenoxybenzophenone, 2, 2 bis [4- (3 aminophenoxy) phenol] 1, 1, 1, 3, 3, 3— Hexafluoropropane, 2, 2 bis [4— (4 aminophenoxy) phenol] 1, 1, 1, 1, 3, 3, 3 Hexafluoropropane, 2, 2 bis [3— (3 aminophenoxy) phenol] 1,1,1,3,3,3 Hexa-Fonole-old lopronone, 2, 2 and 2,3- (4- (aminophenol) phenol) — 1, 1 , 1, 3, 3, 3 Hexafluoropronone, 1,4 bis [4— (3 aminophenoxy) benzoyl] benzene, 1,3 bis [4— (3 aminophenoxy) benzoyl] benzene, 1, 3 Bis (3 amino-4 phenoxybenzoyl) benzene, 1,4 bis (3 amino-4-phenoloxy benzoyl) benzene, 1,3 bis (4 amino-1-phenyl) Noxybenzoyl) benzene, 1,3 bis (4 amino-5 biphenoxybenzoyl) benzene, 1,4 bis (4 amino-5 biphenoxybenzoyl) benzene, 1,3 bis (3 —amino-4 bif Enoxybenzoyl) benzene, 1,4 bis (3 amino-4-biphenoxybenzoyl) benzene, 1,3 bis [4- (4-amino-6 trifluoromethylphenoxy) α, α dimethylbenzyl] benzene, 1, 3 bis [4- (4 amino 6 fluoromethylphenoxy), dimethyl benzyl] benzene, 2, 2, 1 bis (trifluoromethyl) 1, 4, 4, diaminobiphenyl, 3, 3, 1,4,1-diaminobiphenyl, 2,2,1bis (trifluoromethyl) 4,4,1 diaminobiphenyl, 2,2'-dichloro-4,4'-diamino Biphenyl, 3, 3, Dichloro - 4, 4 'Jiaminobi phenyl, 2, 2, single jib port mode 4, 4, over diamino Biff enyl, 3, 3, one jib port mode 4, 4, include over diamino Biff enyl and the like.

 <Tetracarboxylic dianhydrides>

As the tetracarboxylic dianhydride component used in the present invention, known tetracarboxylic dianhydrides can be used. Two or more kinds of acid dianhydrides may be copolymerized. For example, fluorine-free tetracarboxylic dianhydrides include pyromellitic dianhydride, 3, 3 ', 4, 4, monobenzophenone tetracarboxylic dianhydride, 3, 3', 4, 4 , -Biphenyltetracarboxylic dianhydride, 2, 3, 3 ', 4, biphenyl tetracarboxylic dianhydride, 3, 3', 4, 4'-diphenylsulfonetetracarboxylic dianhydride Anhydride, 1, 4, 5, 8—Naphthalenetetracarboxylic dianhydride, 2, 3, 6, 7 Naphthalenetetracarboxylic dianhydride Water, 1, 2, 5, 6 Naphthalenetetracarboxylic dianhydride, 4, 4'-oxydiphthalic anhydride, 3, 3 ', 4, 4'-dimethyldiphenylsilane tetracarboxylic dianhydride, 3, 3 ,, 4, 4'-tetraphenylsilane tetracarboxylic dianhydride, 1, 2, 3, 4 furan tetracarboxylic dianhydride, 4, 4'-bis (3,4-dicarboxyphenoxy) diphenol -Lupropan anhydride, 4,4'-hexafluoroisopropylidene diphthalic anhydride, p-diene diphthalic anhydride, 2,2 bis-((3,4 dicarboxyphenol) Monohexafluoropropane dianhydride, 9, 9 bis (3,4-dicarboxyphenol) fluorene dianhydride, 9, 9'-bis [4- (3,4-dicarboxyphenoxy) phenol- Fluorene dianhydride, 3, 3 ', 4, 4'-biphenyl ether tetracarboxylic dianhydride, 2, 3, 5, 6 pyridine Tracarboxylic dianhydride, 3, 4, 9, 10 Perylenetetracarboxylic dianhydride, 4, 4 'Sulfo-diphthalic dianhydride, Paraterferreux 3, 4, 3', 4, 4-tetracarboxylic dianhydride Anhydride, Metaterferreux 3, 3 ', 4, 4'-tetracarboxylic dianhydride, 3, 3', 4, 4'-diphenyl ether tetracarboxylic dianhydride, 1, 3-bis (3,4) Dicarboxyl) 1, 1, 3, 3—tetramethyldisiloxane dianhydride, 1- (2,3 dicarboxyl) 3— (3,4 dicarboxyl) 1, 1, 3, 3-tetramethyldisiloxane dianhydride, etc. The benzene ring of the above acid dianhydride may have alkyl-substituted and Z- or halogen-substituted sites.

 [0067] Further, when polyimide is used for an optical material as in the present invention, it is preferable that tetracarboxylic dianhydride contains fluorine. This is because the inclusion of fluorine in polyimide can be expected to improve various properties such as high transparency in the near infrared wavelength, low moisture absorption, chemical and thermal stability.

[0068] Fluorine-containing tetracarboxylic dianhydrides include 2, 2 bis-((3,4 dicarboxyl) monohexafluoropropane dianhydride) and (trifluoromethyl) pyromellit. Acid dianhydride, di (trifluoromethyl) pyromellitic dianhydride, di (heptafluoropropyl) pyromellitic dianhydride, pentafluoroethyl pyromellitic dianhydride, bis {3, 5 Di (trifluoromethyl) phenoxy} pyromellitic dianhydride, 2, 2 bis (3,4 dicarboxyphenol) hexafluoropropane dianhydride, 5, 5, -bis (trifluoromethyl) Chill) —3, 3, 4, 4, 4, teracarboxybiphenyl anhydride, 2, 2 ′, 5, 5, —terakis (trifluoromethyl) -3, 3 ′, 4,4, -Tetracarboxybiphenyl anhydride, 5,5'-bis (trifluoromethyl) -3,3 ', 4,4'-tetracarboxydiphenyl ether dianhydride, 5,5 , —Bis (trifluoromethyl) -3,3 ', 4,4, -tetracarboxybenzazophenone dianhydride, bis {(trifluoromethyl) dicarboxyphenoxy} benzene dizenni anhydride, bis ( Dicarboxyphenoxy) (trifluoromethyl) benzene dianhydride, bis (dicarboxyphenoxy) bis (trifluoromethyl) benzene dianhydride, bis (dicarboxyphenoxy) tetrakis (trifluoro) Methyl) benzene dianhydride, 2, 2—bis {(4 (3, 4-dicarboxypheno Bis) hexafluoropropane dianhydride, bis {(trifluoromethyl) dicarboxyphenoxy} biphenol dianhydride, bis {(trifluoromethyl) dicarboxyphenoxy} bis ( Trifluoromethyl) biphenyl anhydride, bis {(trifluoromethyl) dicarboxyphenoxy} diphenyl ether dianhydride, bis (dicarboxyphenoxy) bis (trifluoromethyl) biphenyl Examples include anhydrides.

 [0069] The benzene ring of the acid dianhydride may further have a site substituted with an alkyl group.

 [0070] In order to further reduce transmission loss, it is preferable to contain a fluorine substituent. Furthermore, the tetracarboxylic dianhydride is 2, 2 bis ((3,4-dicarboxyphenyl) monohexafluoropropane dianhydride, because transmission loss is extremely small. Is preferred.

 [0071] Further, from the viewpoint of imparting flexibility, 2, 2 bis ((3,4 dicarboxyphenol) -hexafluoropropane dianhydride power is expressed by the following formula (4). It is also possible to use a polyimide obtained by copolymerizing a polyimide made of tetracarboxylic dianhydride.

[0072] [Chemical 8] Formula (4)

[0073] (where R is —O, one CO—, —SO and a group force consisting of direct bonding forces

 13 2

 One of them. )

 The combination of the fluorine-containing group-containing fluorenediamine component and the tetracarboxylic dianhydride component described here shows one specific example for obtaining the polyimide for optical parts of the present invention. It is possible to adjust the polyimide for optical components of the present invention by changing the combination and use ratio of the tetracarboxylic dianhydride component and the fluorine substituent-containing fluorenedamine component as well as these combinations. Two or more of the above-mentioned tetracarboxylic dianhydrides and diamines may be used in combination. The molar ratio of acid dianhydrides and diamines used in the reaction for producing the polyamic acid solution = (total number of moles of acid dianhydrides) Z (total number of moles of diamines) is 0.9 or more 1. It is preferably 5 or less, more preferably 0.95 or more and 1.3 or less, particularly preferably 0.98 or more and 1.2 or less. Preferred in reducing unreacted acid dianhydride diamin in polyimide resin.

[0074] The diamine and tetracarboxylic dianhydride used for the production of the polyimide are preferably purified before the synthetic reaction. The purification method may be selected from known methods, for example, a recrystallization method in which diamine or tetracarboxylic dianhydride is dissolved in a poor solvent with low solubility while heating and re-precipitated by rapid cooling. It is

 [0075] Further, before synthesizing the polyimide, the diamine-tetracarboxylic dianhydride solution is dissolved in a solvent and filtered through a filter, and if necessary, the solvent is removed and the force is also used for producing the polyimide. May be.

 <Polyimide production method>

The polyimide for optical components of the present invention can be produced by a known production method. That is, one or more tetracarboxylic dianhydride components as raw materials, and one or two A polyamic acid polymer solution is obtained by polymerizing in an organic polar solvent using substantially equimolar amounts of at least one kind of diamine component. Preferred solvents for synthesizing the polyamic acid are amide solvents such as N, N dimethylformamide, N, N dimethylacetamide, N-methyl-2-pyrrolidone, and N, N dimethylformamide is particularly preferred. Preferably used. The reaction apparatus is preferably equipped with a temperature adjusting device for controlling the reaction temperature. The reaction solution temperature is preferably 60 ° C or less, and 40 ° C or less is effective for the reaction. This is also preferable because the viscosity of the polyamic acid is likely to increase.

 The weight% of the polyamic acid in the polyamic acid solution is preferably 5 to 50 wt%, preferably 10 to 40 wt%, more preferably 15 to 30 wt% of the polyamic acid in the organic solvent from the viewpoint of handling. . The average molecular weight of the polyamic acid, when measured in terms of GPC PEG (polyethylene glycol), is such that the weight average molecular weight is 10,000 or more, preferably 50,000 or more, more preferably 100,000 or more. This is preferred when using grease in optical components. If it exceeds 200,000, the solubility becomes low, which is preferable!

 [0077] If necessary, the polyamic acid which is a precursor of the polyimide is imidized. For this imidization, any one of a thermal cure method and a chemical cure method is used.

 [0078] The thermal cure method is a method in which an imidization reaction proceeds by heating alone without the action of a dehydrating ring-closing agent or the like. Specifically, it is cast-coated on a support such as a glass plate, stainless steel belt, or stainless drum, and after the reaction has progressed to the extent that it has self-supporting properties, it is peeled off from the support, and the end is pinned, clipped, It can be obtained by fixing with a gripping jig or other method, and further heating to complete imidization.

 [0079] In the heat curing method, there is a method in which, after the polyamic acid solution is produced, imidization is performed by desolvation and dehydration without heating in a vacuum dryer.

 [0080] In addition, the chemical cure method includes a polyamic acid organic solvent solution, a chemical conversion agent (dehydrating agent) represented by acid anhydrides such as acetic anhydride, and tertiary amines such as isoquinoline, β-picoline, and pyridine. And a catalyst typified by a class. It is also possible to use a calpositimide compound such as dicyclohexyl carpositimide as the dehydrating agent.

[0081] It is preferable to use a dehydrating agent in combination with imidizing from the viewpoint of shortening imidizing time. Examples of such dehydrating agents include aliphatic acid anhydrides such as acetic anhydride and aromatic acid anhydrides. Etc. It is preferable from the viewpoint that acetic anhydride is used for cleaning polyimide resin. The amount of dehydrating agent and imidization accelerator added to the polyamic acid depends on the chemical structure of the polyamic acid, but the amount of dehydrating agent is (molar ratio of dehydrating agent Z molar ratio of amide group in polyamic acid). It can be used to be 3 to 1.2. If the amount of the dehydrating agent is small, it may take time for the imidation to proceed. On the other hand, if the amount is too large, the molecular weight may be lowered.

 [0082] Of course, the reaction conditions for imidization in which the chemical curing method and the thermal curing method may be used in combination are the type of polyamic acid, the form of the obtained resin, the thermal curing method, and the Z or chemical curing method. It may vary depending on the selection.

 [0083] The temperature during imidization is preferably 50 ° C to 120 ° C, and the heating time is preferably 1 to 10 hours.

 [0084] The extraction method of the imide resin powder of the present invention will be described. As a method for extracting a polyimide resin powder from a solution containing the polyimide resin obtained as described above, a polyimide resin solution containing a polyimide resin and an imido accelerator is contained in a poor solvent for the polyimide resin. It is possible to use a method in which polyimide resin is extracted into a solid state. The polyimide resin powder of the present invention is in the form of a solid including powder, flakes and various forms, and the average particle size is preferably 5 mm or less, more preferably 3 mm or less, especially lmm or less is preferable.

[0085] The poor solvent for polyimide resin used in the present invention is a poor solvent for polyimide resin, which is mixed with an organic solvent used as a solvent in which polyamic acid and polyimide resin are dissolved. Can be used. For example, water, methyl alcohol, ethyl alcohol, isopropyl alcohol, ethylene glycolanol, triethylene glycol, 2-butanol monole, 2-pentanol monore, 2-hexanol nore, cyclopentenoleanoreconole, cyclohexenole alcohol, Examples include phenol and t-butyl alcohol. Among the above alcohols, alcohols such as isopropyl alcohol, 2-butanol, 2-pentanol, phenol, cyclopentyl alcohol, cyclohexyl alcohol, and t-butyl alcohol increase the stability of the polyimide resin after extraction. The viewpoint power that the imidization rate becomes high is preferable. Furthermore, isopropyl alcohol is preferred! /. [0086] Charging method: When a polyimide resin solution is charged into a poor solvent, after diluting so that the solid content concentration of the polyamic acid solution is 15% or less, preferably 10% or less. The polyimide solution is preferably introduced into the poor solvent solution. In order to completely remove the solvent in the drying process, it is preferable that the diameter immediately before the polyimide resin solution is introduced is 1 mm or less, and more preferably that the diameter is 0.5 mm. The amount of the poor solvent is preferably extracted in an amount that is at least three times that of the polyimide resin solution.

 [0087] For example, since the resin may become thread-like immediately after the addition of the resin, it is as fine as possible! / * In order to obtain a flake-shaped polyimide resin powder, it is necessary to stir in a poor solvent. I like it. Also, if the amount of solvent used for dissolving the polyimide in the poor solvent becomes large after completely adding the polyimide resin solution, the polyimide resin dissolves. It is preferable to add the same amount of solvent, more preferably twice the amount of solvent. By adding a large amount of solvent, the imide resin dissolved in the poor solvent is precipitated again and becomes a powdery resin.

 [0088] Cleaning method: Solid polyimide resin is taken out and washed in a poor solvent such as alcohol.

[0089] Drying method: The method for drying the solidified flaky solid material in the present invention may be vacuum drying or hot air drying. Coloring may occur at a drying temperature of 120 ° C or higher in the presence of oxygen. Therefore, it is desirable to dry at 120 ° C or less. It is desirable to carry out at 120 ° C or less even in vacuum or in an inert gas atmosphere.

 [0090] The molecular weight of the polyimide resin prepared by the above method is preferably a weight average molecular weight of 10,000 or more and 500,000 or less when measured in terms of PEG (polyethylene glycol) of GPC. It is preferably 50,000 or more and 400,000 or less, particularly preferably 80,000 or more and 300,000 or less. When polyimide resin is applied to the surface of a film body, for example, it is easy to handle with few spots. This is preferable.

The polyimide resin powder thus obtained has high imidization rate and molecular weight for practical use with high solubility in organic solvents. Here, the practically sufficient imidi ratio and molecular weight are determined by those skilled in the art depending on the application, but generally the imido ratio is 95% or more, preferably 98% or more, more preferably 99% or more. , Weight average molecular weight more than 50,000, Preferably it is 80,000 or more, more preferably 100,000 or more. If it is 200,000 or more, the solubility tends to decrease.

[0091] The polyimide obtained as described above is usually used by dissolving in a solvent.

[0092] Solvents for dissolving polyimide include amide solvents, that is, N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, and the like. N, N-dimethylformamide , Dioxolane, methyl ethyl ketone, and the like.

[0093] As a method for adjusting the polyimide solution, a method of adding a solvent after pulverization or pulverization,

There is a method in which a powdery or pulverized polyimide is introduced into a solvent and dissolved. After dissolving the polyimide in a large amount of solvent, the concentration of the polyimide solution may be increased by volatilizing the solvent spontaneously. Moreover, you may heat during melt | dissolution as needed.

[0094] After the polyimide resin is added to the organic solvent, it may be mixed by centrifugation using a centrifuge, or may be vibrated.

[0095] The concentration of the polyimide solution is preferably 10 wt% or more and 60 wt% or less.

. Furthermore, a concentration of 20% by weight or more is preferable because the thickness of the polyimide thin film or polyimide film can be accurately controlled.

[0096] When the content is less than 10% by weight, for example, when a spin coating or the like is performed to form a polyimide thin film on a silicon substrate, a smooth and uniform thin film may not be formed.

 [0097] If the concentration of the polyimide solution exceeds 60% by weight, the flowability of the polyimide solution tends to be extremely poor, and if it is severe, it does not flow.

[0098] Furthermore, when a polyimide film or a polyimide thin film is formed, the uniformity of the thickness, which is poor in smoothness, is lost, and defects such as the inclusion of minute bubbles in the polyimide thin film or the polyimide film may occur. is there.

[0099] The polyimide solution is more preferable as it has a smaller particle content.

[0100] Here, the particles refer to dust in the air, dust, components not dissolved in the solvent, and the like. If there are many particles, light scattering will occur and input light power will be lost.

[0101] Specifically, the content of particles of 0.3 m or more is preferably 50000 particles / g or less. Less particle content is preferred! /. [0102] Examples of a method for removing 0.3 μm particles include a method of filtering a polyimide solution using a membrane filter or the like. In order to efficiently filter, synthesis of polyimide resin may be started after diamine and tetracarboxylic dianhydride before synthesis of polyimide are filtered using a 0.2 m membrane filter. .

 [0103] The polyimide for optical components of the present invention is dioxolane, dimethylformamide, N-methyl.

 The solubility at 25 ° C. in a single solvent or mixed solvent selected from 2-pyrrolidone, N, N dimethylacetamide and methyl ethyl ketone is preferably 20% by weight or more. If the amount is less than 20% by weight, the volume of the polyimide solution increases and the volume required for storage increases. In addition, when forming a thin film using the solution, the solution viscosity is small, and the solute This is because there is a tendency that V cannot obtain a thin film having a desired thickness because the concentration of V is low.

 [0104] When the concentration of the polyimide solution exceeds 60% by weight, when a polyimide film or a polyimide thin film is formed, the uniformity of thickness is lost due to poor smoothness, and minute bubbles are formed in the polyimide thin film or polyimide film. When defects such as inclusion occur, there are other problems.

 [0105] The optical component of the present invention contains polyimide and Z or polyamic acid. Polyamic acid is a precursor of the polyimide. The production method of the polyamic acid is the same as that described in the column “Production Method of Polyimide” above.

[0106] The glass transition temperature (hereinafter, Tg) of the polyimide resin in the present invention is preferably 150 ° C or higher. If the temperature falls below 150 ° C, it may not be able to withstand long-term reliability tests and nonder reflow processes, resulting in malfunctions.

[0107] As a method for measuring Tg, a known method may be used. It only has to comply with JIS K 7121: 1987.

[0108] Examples include the TMA method, the DSC method, and the DMA method. In the TMA method, the temperature of a specimen is raised from room temperature, for example, at a rate of 10 ° CZ, and the amount of thermal expansion in the thickness direction is measured with a thermal analyzer, and the horizontal axis represents temperature and the vertical axis represents thermal expansion coefficient. Create a plotted graph. In this method, a tangent line is drawn on the curve before and after the glass transition point, and Tg is obtained from the intersection of these tangent lines. In the DSC method, the test piece is heated at room temperature, for example, at a rate of 20 ° CZ, and the calorific value is measured with a differential scanning calorimeter. And create a graph with temperature on the horizontal axis and calorific value on the vertical axis. In this graph, two extension lines are drawn on the endothermic curve and exothermic curve, and Tg is obtained from the intersection of the 1Z2 line and endothermic curve between the extension lines. The DMA method is also called a tensile method. For example, the test piece is heated from room temperature at a rate of 2 ° CZ, and the dynamic viscoelasticity and loss tangent of the test piece are measured with a viscoelasticity measuring device. This is a method of creating a graph plotting the temperature on the horizontal axis, the elastic modulus on the first vertical axis, and the loss tangent on the second vertical axis, and obtaining Tg from the peak temperature of the loss tangent. Since the data obtained tends to be slightly different depending on the method used, in the present invention, the value obtained by the DMA method is adopted as Tg.

 [0109] The heat resistance of the polyimide for optical components in the present invention is measured according to JIS c 0021: 1995. Similarly, moisture resistance (JIS c 0032: 1996), cold resistance (JIS c 0020: 1995), flex resistance CFIS K 6272: 2003) are measured according to each JIS standard.

 [0110] The heat resistance of the polyimide for optical components in the present invention is preferably 150 ° C or higher, preferably 180 ° C or higher, and more preferably 200 ° C or higher. This is because the higher the heat resistance, the better the heat resistance of the solder, and it can withstand a heating process such as a reflow process even if it is mixed with electrical wiring, thereby expanding the range of applications.

 [0111] When an optical waveguide is produced using the polyimide for an optical component in the present invention, the mechanical and physical properties of the optical waveguide, particularly when used for an optical waveguide core, include the following. That is, there are a bending test, a high temperature storage test, a low temperature storage test, a high temperature and high humidity storage test, a temperature and humidity cycle test, and a temperature cycle test. The evaluation of each test is expressed as the change in insertion loss [dB] into the optical waveguide. The details of the test are described in JPCA standards (JPCA-PE02-05-01S-2004) as a test method for polymer optical waveguides.

 [0112] In each test, the change in insertion loss before and after the test is 3 dB or less, more preferably 2 dB or less, and further preferably 1 dB or less. Since the optical signal transmission loss is small, the size of the mounting package can be reduced and the output of the optical signal light source can be reduced.

[0113] If the insertion loss exceeds 3 dB, it may be inferior in practical resistance when used in mobile devices or information appliances, and may shorten the product life. [0114] When the optical component is an optical waveguide, its cross-sectional shape varies depending on the fabrication process. For example, the method using photolithography and RIE is rectangular (square, rectangular, trapezoidal), and the self-forming optical waveguide fabrication process is greatly affected by the laser beam profile that hardens the resin. When the laser is emitted from one optical fiber, the cross-sectional shape of the produced optical waveguide tends to be a circle or an ellipse.

 [0115] What kind of cross-sectional shape is good depends on the application, and a suitable shape may be selected.

 [0116] The shape of the optical waveguide is often linear when used simply as an optical wiring for transmitting light. When the optical wiring is provided with a coupling / branching function, for example, a Y-branching structure or a ring shape may be used. Also, in an opto-electric hybrid board where optical and electrical wiring are mixed, the optical wiring may be made three-dimensional in order to transmit the light to the necessary place. For this reason, there is a form of an optical waveguide having a three-dimensional structure.

 [0117] An opto-electric hybrid board is one in which both optical signals and electric signals are formed on a single board including a laminate, and a thin insulating material is used for the base, and an electric distribution is provided on the base. Lines are formed, and optical wiring is connected in the form of lamination or connection, and a transformation (photodetector, laser diode, etc.) that converts optical signals and electrical signals into each other is mounted.

 [0118] As an electrical wiring material, a metal alloy such as copper, aluminum, nickel, gold, and stainless steel, and a paste containing conductive carbon or silver powder are used as the electrical wiring material.

 [0119] The electrical wiring portion of the opto-electric hybrid board is wired in the form of one or both surfaces of the insulating material substrate, multilayer, and the like. Other forms include rigid 'flex', double-sided exposed structure and fly-in-grade.

 [0120] Among optical components, the application range of the optical waveguide is particularly wide. Optical components, particularly optical waveguides and multiplexers / demultiplexers are generally used for an opto-electric hybrid board that uses both optical signals and electrical signals.

[0121] The opto-electric hybrid board has a configuration in which the optical transmission layer and the electric transmission layer are separately configured and further laminated, or in the same layer as the electric transmission layer, the optical wiring by the optical waveguide. Shape Depending on the application, there are various forms.

 [0122] The opto-electric hybrid board has a plate-like and solid board that can be bent freely with a certain radius of curvature. The former is called a rigid board. The latter is called a flexible substrate.

 [0123] For example, to describe a flexible opto-electric hybrid board, there are an electric wiring portion and an optical wiring portion, and the electric wiring portion is already formed after the electric wiring portion is formed by a known method. In some cases, a film or the like is laminated on an already produced electric wiring part, or after the electric wiring part is formed, the optical wiring part is formed in the same plane.

 [0124] In addition, the electrical wiring portion and the optical wiring portion may be formed separately on the upper and lower sides of the insulating material substrate.

 [0125] The opto-electric hybrid board is applied to a device that requires high-speed signal exchange and causes large electric signal transmission loss due to electric noise. For example, wiring (display module) that connects the display of the mobile phone to the operation unit, the inside of a small hard disk such as a DVD, HDD VD, or Blue-Ray disk, the signal pickup of the CD pickup unit, and the print head unit of the inkjet printer And notebook PCs have a wiring section that connects the liquid crystal display and the hard disk section.

 [0126] Also, it is used for inter-board wiring of backplane boards, large-capacity servers, routers, etc., which are optical communication devices that are not such small devices, and also covers high-speed LSI chips. Sarahoko, boards in copiers, wiring boards for in-vehicle control equipment. In addition, opto-electric hybrid boards can be used in TVs (two-way communication, etc.), DVD devices, home game machines, etc., which have recently been integrated with the Internet.

 [0127] In order to convert an optical signal into an electrical signal, the optical signal needs to be incident on a light receiver.

When transmitting an optical signal, for example, light transmitted through an optical waveguide with a large curvature that seems to be sufficient if the optical waveguide is connected to a linear part or curved part on a substrate and finally connected to a light receiver. Leaks into the cladding without being confined to the core of the optical waveguide, resulting in extremely low transmission efficiency. Therefore, it is rather undesirable to use an optical waveguide having a large curvature. Therefore, when there is no light receiver on the extension line of the optical waveguide, the optical signal may be reflected and incident on the light receiver using a 45 degree mirror or the like. Similarly, a mirror may be used when light is incident on the core portion of the optical waveguide. The In some cases, one end of an optical fiber cut into a V-groove is used to extract an optical signal.

 [0128] The index for evaluating the bending resistance of the polyimide for optical components in the present invention was the number of bendings at which the conductor resistance value increased by 80% or more. A flexible printed circuit board produced using the polyimide resin for optical components (the structure is as follows: an adhesive layer is formed on a base film, and a conductor circuit is formed on the adhesive layer. It has a further adhesive layer so as to cover the whole, and a cover lay is laminated on this adhesive layer) into a rectangular shape with a width of 7mm and a length of 150mm. Obtain the number of flexing times when the conductor resistance rises by 80% or more. That is, the ambient temperature is 80 ° C, the stroke is 25 mm, the bending speed is 25 Hz, and the curvature radius is 2 mm.

 [0129] When the polyimide for an optical component according to the present invention is formed on the flexible printed board having the above-described configuration, the number of bendings is 10,000 times or more, preferably 100,000 times or more. This is because practical durability is extended and product life can be extended.

 [0130] Considering that the opto-electric hybrid board is also used as a display module of a mobile phone as described above, it is required to have bending resistance. The evaluation of the bending resistance may be based on the bending resistance test described above. For an opto-electric hybrid board, the bending resistance is 10,000 times or more, preferably 100,000 times or more in terms of the number of times of bending. This is because practical durability is extended and product life can be extended.

 [0131] In the bending resistance evaluation (MIT test) in the examples of the present invention, a 50 m film was cut into a rectangular shape with a width of 15 mm and a length of 110 mm, an ambient temperature of 25 ° C, a radius of curvature of 0.38 mm, and a bending angle. A bending test was conducted under the conditions of 135 °, a bending speed of 3 Hz, and a load of lOOg.

 [0132] Among optical components, the form of an optical waveguide is particularly frequently used. In order to build FTTH, we will make ONU, which is a device for connecting the optical fiber drawn into each home to a PC. The ONU has a function of once entering an optical signal from the optical fiber into the optical waveguide, entering the photodiode, and converting it into an electrical signal.

It is necessary to connect the optical waveguide and the optical fiber, but it is necessary to perform optical axis alignment with high accuracy. At that time, a V-groove for fixing the POF to the substrate may be formed. The V When an optical fiber is set in the groove, the optical axis of the optical component including the optical waveguide (for example, in the case of an optical waveguide) is at the height where the optical fiber core comes. Just design the optical components. By using the V-groove, the optical connection between the optical fiber and an optical component such as an optical waveguide can be improved.

 [0133] The polyimide for an optical component in the present invention includes an add / drop for extracting and adding an optical signal as necessary, a wavelength filter for combining or demultiplexing optical signals of different wavelengths into one fiber, and an optical signal. Mach-Zehnder type optical switches that turn signals on and off, thermo-optic type optical switches, etc. are also examples of optical components.

 [0134] The polyimide for optical components according to the present invention can be suitably used as an in-vehicle optical component because of its high heat resistance and long-term reliability. In other words, any optical component can be used as long as it is used for in-vehicle LAN. For example, an optical component used in a display module in a car navigation system, for example, an optical waveguide, a multiplexer / demultiplexer, etc. .

 Example

 Hereinafter, the present invention will be specifically described based on examples. However, the present invention is not limited to these examples, and various modifications can be made.

 [Example 1]

 In a container with a stirring blade, put dimethylformamide (DMF) fully dehydrated in a molecular sieve into lOOOg, and store 77 g of 9, 9-bis (3-fluoro-4-aminophenol) fluorene. Stir until completely dissolved. The system was cooled to 0 ° C and gradually added 89 g of 2,2-bis ((3,4-dicarboxyphenol) monohexafluoropropane dianhydride and stirred for 3 hours. Thus, a polyamic acid (polyamic acid) solution I was obtained.

 Next, 17 g of isoquinoline as a catalyst and 120 g of acetic anhydride as a dehydrating agent were added to the above solution, followed by stirring at 100 ° C. for 1 hour to obtain a polyimide solution.

 [0138] The obtained polyimide solution was dropped into a large amount of isopropyl alcohol to precipitate the polyimide, which was sufficiently dried at 80 ° C under reduced pressure to obtain polyimide I.

[0139] 2 g of the obtained polyimide was dissolved in 4 cc of dimethylformamide (DMF) and filtered using a membrane filter having an eye of 0.5 m. Filtration solution lcc silicon substrate with oxide film ( 4 inches diameter), spin-coated at lOOOrpm. For 20 seconds, and dried at 80 ° C for 10 minutes to obtain a 6 m thick thin film. The thickness of the thin film prepared by spin coating was mechanically measured separately after cleaving the silicon substrate with an oxide film and peeling off the thin film.

 [0140] Refractive index measurement was performed at a wavelength of 830 nm and a wavelength of 633 nm using a prism force plastic model 2010 (manufactured by Metricon). Table 1 shows the measurement results at a wavelength of 830 nm. The refractive index at a wavelength of 633 nm was 1.59557 in the TE mode and 1.59466 in the TM mode, and the refractive index difference was very low at 0.00091.

 [0141] Prism force plastic model 2010 (manufactured by Metricon) was used for transmission loss measurement. Transmission loss was measured by introducing and propagating a laser beam having a wavelength of 830 nm and a wavelength of 633 nm to a polyimide thin film formed on a silicon substrate with an oxide film by a prism force bra method. The polarization of one laser beam was measured separately for the TE mode and the TM mode. Table 1 shows the measurement results. As can be seen from Table 1, Polyimide I has an extremely small transmission loss value. Table 1 shows the measurement results of the number of MIT test bends.

[0142] [Table 1]

[0143] 2, 2, 1 Bis (trifluoromethyl) 4, 4, 1 on a silicon substrate by spin coating After forming diaminobiphenyl and 2, 2 bis ((3,4 dicarboxyphenyl) -hexafluoropropane dianhydride force polyimide (hereinafter referred to as polyimide VI) thin film (thickness 10 m), An 8 m thick polyimide resin I thin film was formed by spin coating, followed by photomask coating, photolithography and RIE, and polyimide VI was formed as an upper cladding with a thickness of 10 μm. An optical waveguide with a core width of 8 μm and a length of 40 mm was obtained.

 [0144] Both end surfaces of the optical waveguide were cut out by dicing, light having a wavelength of 830 nm was incident on the optical waveguide with a quartz single mode fiber, and the intensity of the emitted light was measured with an optical power meter. The same measurement was performed every time dicing the optical waveguide length to 30 mm, 20 mm, and 10 mm, and the horizontal axis represents the optical waveguide length, and the vertical axis represents the optical power transmitted through the optical waveguide. Then, the transmission loss as an optical waveguide calculated from the graph and linear approximation is calculated from the slope of the straight line is 0.2 dBZcm.

 Therefore, by using the polyimide for an optical component in the present invention, a low-loss optical waveguide can be formed, and by using the optical waveguide core to form the optical wiring portion of the opto-electric hybrid board. In addition, the power consumption of the light source incident on the optical waveguide can be reduced, and when used as an opto-electric hybrid board, high-speed data transmission and low power consumption are achieved as compared with the electric wiring board.

 [0146] (Example 2)

 Except that the diamine component was changed to 39 g of 9, 9-bis (3-fluoro-4-aminophenol) fluorene and 32 g of 2,2,1bis (trifluoromethyl) 4,4, -diaminobiphenyl. A polyimide cage was obtained in the same manner as in Example 1. For Polyimide II, the bending test, the transmission loss, and the refractive index were measured in the same manner as in Example 1. The thin film thickness was 7 m. The results are shown in Table 1. From this result, it can be seen that by using a copolymerization diamine in addition to a diamine having at least a fluorine substituent and a fluorenyl group, it has sufficiently low transmission loss and high flexibility. Therefore, it can be seen that it is suitable for optical components, particularly for optical waveguide cores.

 [Example 3]

The diamine component was added to 39 g of 9, 9-bis (3-fluoro-4-aminophenol) fluorene. A polyimide film was obtained in the same manner as in Example 1, except that 44 g of bibis [4- (3-aminophenoxy) phenol] sulfone was used. For Polyimide III, the bending test, transmission loss and refractive index measurement were performed in the same manner as in Example 1. The thin film thickness was 10 m. The results are shown in Table 1. From this result, it can be seen that, in addition to diamine having at least a fluorine substituent and a fluorenyl group, copolymerization diamine has a sufficiently low transmission loss and high flexibility. Therefore, it is obvious that it is suitable for optical components, particularly for optical waveguide cores.

 [0148] (Comparative Example 1)

 Polyimide and IV were obtained in the same manner as in Example 1 except that the diamine component was changed to 70 g of 9,9bis (4-aminophenol) fluorene. For polyimide and IV, bending test, transmission loss and refractive index measurement were performed in the same manner as in Example 1. The thin film thickness was 8 m. The results are shown in Table 1. From this result, it can be seen that when there is no fluorine substituent in diamine, the transmission loss at a wavelength of 633 nm is clearly high, which is unsuitable for optical components at this wavelength as compared with the examples.

 [0149] (Comparative Example 2)

 Polyimide V was obtained in the same manner as in Example 1 except that the diamine component was changed to 64 g of 2,2,1bis (trifluoromethyl) 4,4, diaminobiphenyl. For polyimide V, bending test, transmission loss and refractive index measurement were performed in the same manner as in Example 1. The thin film thickness was 8 m. The results are shown in Table 1. Looking at the results, the transmission loss at wavelengths of 830 nm and 633 nm exceeded ldBZcm regardless of the polarization direction. Therefore, it can be seen that polyimide V is not suitable as an optical component at these wavelengths.

Claims

The scope of the claims

 [1] A polyimide comprising diamines containing diamine having at least a fluorine substituent and a fluorenyl group and tetracarboxylic dianhydride, and transmission loss at a wavelength of 830 nm is less than ldBZcm in both TE mode and TM mode. Polyimide for optical parts, characterized by

 [2] The polyimide for optical parts according to claim 1, wherein the transmission loss at a wavelength of 633 nm is ldBZcm or less in both the TE mode and the TM mode.

 [3] The amino group of the diamine having a fluorine substituent and a fluorenyl group is bonded to an aromatic ring,

 3. The polyimide for an optical component according to claim 1, wherein the fluorine substituent is located at the ortho position of the amino group.

[4] The polyimide for optical parts according to claim 1 or 2, wherein the diamine having a fluorine substituent and a fluorenyl group is a diamine represented by the following formula (1).

 [Chemical 1]

(In the formula, R to R may be the same or different from each other, either hydrogen or fluorine.

 1 8

 And at least one is fluorine. )

 [5] The polyimide for optical parts according to claim 1 or 2, wherein the polyimide is a diamine force 9, 9 bis (3-fluorine-4-aminophenol) fluorene having the fluorine substituent and the fluorenyl group.

 [6] The diamines include the diamine having a fluorine substituent and a fluorenyl group and at least one copolymerized diamine.

The polyimide for optical components according to any one of claims 1 to 5, wherein the copolymerized diamine is a diamine represented by the following formula (2). [Chemical 2]

Formula (2)

(Any two of X to X in the formula are NH, and the remaining eight are from H, CH and CF.

 1 10 2 3 3 One force selected from the group consisting of one group. R is — O—, — S—, —SO—,

 11 2 CH —, one CO—, -C (CH) one, C (CF) —, -O-R O, one fluoride

2 3 2 3 2 12

 -Lu group- and direct bond force are group forces. Where R

 12 is an alkyl group having 1 or more and 5 or less carbon atoms, and a group force which is selected as a group force represented by the following formula group (3).

 [Chemical 3]

[7] The copolymerized diamine is 4,4′-diaminodiphenyl ether, 3,4′-diaminodiphenyl

-Luether, 2,2'-Bis (trifluoromethyl) -4,4'-Diaminobiphenyl, 4,4'-Diaminodiphenylsulfone, 1,5- (4-Aminophenoxy) pentane, 1, 3- Bis (4-aminophenoxy) -2,2-dimethylpropane, 2,2-bis (4-aminophenoxyphenol) propane, 2,2-bis [4- (4 aminophenoxy) phenol] Xafluoropropane, bis [4- (4-aminophenoxy) phenol] sulfone, and bis [4- (3-aminophenoxy) phenol] sulfone power group power of at least one selected diamine The polyimide for optical parts according to claim 6, wherein the polyimide is for optical parts.

[8] The polyimide for optical parts according to any one of [1] to [7], wherein the tetracarboxylic dianhydrides include a tetracarboxylic dianhydride having a fluorine substituent.

[9] Tetracarboxylic dianhydride analog 2, 2-bis (((3,4-dicarboxyphenyl)

The polyimide for optical parts according to any one of claims 1 to 7, characterized in that it comprises (a) hexafluoropropane dianhydride).

[10] The tetracarboxylic dianhydrides are 2, 2-bis (((3,4-dicarboxyphenyl)

) Monohexafluoropropane dianhydride) and one or more types of copolymerized tetracarboxylic dianhydrides,

 The optical component polycarboxylic acid according to any one of claims 1 to 7, wherein the tetracarboxylic dianhydride for copolymerization is a tetracarboxylic dianhydride represented by the following formula (4): Imide.

 [Chemical 4]

(In the formula, R is —O—, one CO—, —SO —, and a group force that is a direct bond force.

 13 2

 One of them. )

 [11] The polyimide for an optical component according to any one of [1] to [10], wherein the transmission loss at the wavelength of 830 nm is 0.1 dBZcm or less in both the TE mode and the TM mode.

[12] The polyimide for optical parts according to any one of [2] to [10], wherein the transmission loss at the wavelength of 633 nm is 0.1 dBZcm or less in both the TE mode and the TM mode.

[13] The refractive index at a wavelength of 830 nm is 1.55 or more for both TE mode and TM mode,

The difference in refractive index between the TE mode and the TM mode is 0.01 or less.

The polyimide for optical parts according to any one of 2 above.

[14] The refractive index at a wavelength of 633 nm is 1.55 or more in both TE mode and TM mode,

The difference in refractive index between the TE mode and the TM mode is 0.01 or less.

The polyimide for optical parts according to any one of 2 above.

[15] It is characterized in that it can be bent more than 300 times in the MIT bending test with a bending radius of 0.38 mm, bending angle of 135 ° and load of 100 g when it is formed into a film with a thickness of 50 / zm. The polyimide for optical parts according to any one of claims 1 to 14.

 [16] Dioxolane, dimethylformamide, N-methyl-2-pyrrolidone, N, N dimethylacetamide and methylethylketone group strength at least one single solvent or two or more mixed solvents at 25 ° C The polyimide for optical parts according to any one of claims 1 to 15, wherein the solubility of is 20% by weight or more.

 [17] Polyamic acid, which is a precursor of the polyimide for optical parts according to any one of claims 1 to 16.

 [18] An optical component comprising the polyimide according to any one of claims 1 to 16 and Z or the polyamic acid according to claim 17.

[19] An optical waveguide comprising the polyimide according to any one of claims 1 to 16 and Z or the polyamic acid according to claim 17.

[20] In an optical waveguide having a core and a clad, a polyimide comprising at least a diamine containing diamine having a fluorine substituent and a fluorenyl group and tetracarboxylic dianhydride is used as a core. , Optical waveguide.

[21] The transmission loss of the optical waveguide at a wavelength of 830 nm is Id for both TE mode and TM mode.

21. The optical waveguide according to claim 20, wherein the optical waveguide is BZcm or less.

[22] The transmission loss of the optical waveguide at a wavelength of 633 nm is Id for both TE mode and TM mode.

The optical waveguide according to claim 20, wherein the optical waveguide is BZcm or less.