CN114080408B - Cured product, overcoat film, and flexible wiring board - Google Patents

Cured product, overcoat film, and flexible wiring board Download PDF

Info

Publication number
CN114080408B
CN114080408B CN202080049525.8A CN202080049525A CN114080408B CN 114080408 B CN114080408 B CN 114080408B CN 202080049525 A CN202080049525 A CN 202080049525A CN 114080408 B CN114080408 B CN 114080408B
Authority
CN
China
Prior art keywords
polyurethane
curable resin
cured product
resin composition
mass
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN202080049525.8A
Other languages
Chinese (zh)
Other versions
CN114080408A (en
Inventor
石桥圭孝
召田小雪
山下未央
木村和弥
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Japan Poly Co
Original Assignee
Japan Poly Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Japan Poly Co filed Critical Japan Poly Co
Publication of CN114080408A publication Critical patent/CN114080408A/en
Application granted granted Critical
Publication of CN114080408B publication Critical patent/CN114080408B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/01—Use of inorganic substances as compounding ingredients characterized by their specific function
    • C08K3/013—Fillers, pigments or reinforcing additives
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00—Polymeric products of isocyanates or isothiocyanates
    • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
    • C08G18/40—High-molecular-weight compounds
    • C08G18/4009—Two or more macromolecular compounds not provided for in one single group of groups C08G18/42 - C08G18/64
    • C08G18/4045—Mixtures of compounds of group C08G18/58 with other macromolecular compounds
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B15/00—Layered products comprising a layer of metal
    • B32B15/04—Layered products comprising a layer of metal comprising metal as the main or only constituent of a layer, which is next to another layer of the same or of a different material
    • B32B15/08—Layered products comprising a layer of metal comprising metal as the main or only constituent of a layer, which is next to another layer of the same or of a different material of synthetic resin
    • B32B15/092—Layered products comprising a layer of metal comprising metal as the main or only constituent of a layer, which is next to another layer of the same or of a different material of synthetic resin comprising epoxy resins
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B15/00—Layered products comprising a layer of metal
    • B32B15/04—Layered products comprising a layer of metal comprising metal as the main or only constituent of a layer, which is next to another layer of the same or of a different material
    • B32B15/08—Layered products comprising a layer of metal comprising metal as the main or only constituent of a layer, which is next to another layer of the same or of a different material of synthetic resin
    • B32B15/095—Layered products comprising a layer of metal comprising metal as the main or only constituent of a layer, which is next to another layer of the same or of a different material of synthetic resin comprising polyurethanes
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00—Polymeric products of isocyanates or isothiocyanates
    • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/08—Processes
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00—Polymeric products of isocyanates or isothiocyanates
    • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
    • C08G18/40—High-molecular-weight compounds
    • C08G18/42—Polycondensates having carboxylic or carbonic ester groups in the main chain
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00—Polymeric products of isocyanates or isothiocyanates
    • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
    • C08G18/40—High-molecular-weight compounds
    • C08G18/42—Polycondensates having carboxylic or carbonic ester groups in the main chain
    • C08G18/44—Polycarbonates
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00—Polymeric products of isocyanates or isothiocyanates
    • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
    • C08G18/40—High-molecular-weight compounds
    • C08G18/48—Polyethers
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00—Polymeric products of isocyanates or isothiocyanates
    • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
    • C08G18/40—High-molecular-weight compounds
    • C08G18/58—Epoxy resins
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G59/00—Polycondensates containing more than one epoxy group per molecule; Macromolecules obtained by polymerising compounds containing more than one epoxy group per molecule using curing agents or catalysts which react with the epoxy groups
    • C08G59/18—Macromolecules obtained by polymerising compounds containing more than one epoxy group per molecule using curing agents or catalysts which react with the epoxy groups ; e.g. general methods of curing
    • C08G59/40—Macromolecules obtained by polymerising compounds containing more than one epoxy group per molecule using curing agents or catalysts which react with the epoxy groups ; e.g. general methods of curing characterised by the curing agents used
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/34—Silicon-containing compounds
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/34—Silicon-containing compounds
    • C08K3/36—Silica
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L101/00—Compositions of unspecified macromolecular compounds
    • C08L101/12—Compositions of unspecified macromolecular compounds characterised by physical features, e.g. anisotropy, viscosity or electrical conductivity
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L63/00—Compositions of epoxy resins; Compositions of derivatives of epoxy resins
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L75/00—Compositions of polyureas or polyurethanes; Compositions of derivatives of such polymers
    • C08L75/04—Polyurethanes
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L75/00—Compositions of polyureas or polyurethanes; Compositions of derivatives of such polymers
    • C08L75/04—Polyurethanes
    • C08L75/06—Polyurethanes from polyesters
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K3/00—Apparatus or processes for manufacturing printed circuits
    • H05K3/22—Secondary treatment of printed circuits
    • H05K3/28—Applying non-metallic protective coatings

Landscapes

  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Paints Or Removers (AREA)
  • Polyurethanes Or Polyureas (AREA)
  • Epoxy Resins (AREA)

Abstract

The invention provides a cured product which has excellent property of making a flexible wiring board difficult to warp and property of inhibiting wiring of the flexible wiring board from breaking. A cured product is obtained by curing a curable resin composition, wherein a free induction decay signal f (T) for determining the magnetization of a proton at a spin-spin relaxation time T2 is measured by a pulse nuclear magnetic resonance method at a measurement frequency of 20MHz, and when the free induction decay signal f (T) is approximated by the following numerical expression, the free induction decay signal f (T) is calculated from [ A (1) ×T2 (1) +A2) ×T2 (2) calculated from A (1), A (2), T2 (1) and T2 (2) in the following numerical expression]The value of (2) is 0.015ms or less, and T2 (3) is 0.50ms or more. [ mathematics 1 ]]

Description

Cured product, overcoat film, and flexible wiring board
Technical Field
The present invention relates to a cured product, an overcoat film, and a flexible wiring board.
Background
The flexible wiring board is covered with an overcoat film for protecting the surface. The overcoat film is formed by applying a curable resin composition onto the surface of a flexible substrate on which wiring is formed by a printing method or the like, and curing the composition. With the fine wiring treatment of a circuit formed on a flexible wiring board and the weight and size reduction of a module, a curable resin composition for forming an overcoat film is required to have a property of making a flexible substrate less likely to warp, as compared with the prior art. If the flexible substrate is warped, the positioning accuracy of the mounting position of the IC chip may be adversely affected when the IC chip is mounted on the flexible wiring board in the packaging process, and the yield in the manufacturing process may be lowered.
A number of curable resin compositions for forming an overcoat film of a flexible wiring board for electronic devices and the like have been proposed in the prior art, and for example, patent document 1 discloses a curable resin composition containing a polyurethane obtained by reacting a diisocyanate compound with a plurality of diol compounds. When the curable resin composition disclosed in patent document 1 is used, an overcoating film for a flexible wiring board having low warpage and excellent flexibility, long-term insulation reliability, and wire breakage inhibition of wiring can be obtained.
Prior Art
Patent literature
Patent document 1: international publication No. 2017-110591
Disclosure of Invention
Technical problem to be solved by the invention
However, with the development of the semi-additive method, the distance (pitch) between the wires of the flexible wiring board is further narrowed (for example, 20 μm or less), and therefore, it is desired to further improve the low warpage property of the flexible wiring board and the wire breakage suppression property of the wires of the flexible wiring board.
The present invention addresses the problem of providing a cured product, an overcoat film, and a flexible wiring board that have excellent low warpage properties (hereinafter, the property of making the flexible wiring board less likely to warp and the property of making the flexible wiring board less likely to warp are sometimes referred to as "low warpage properties") and wire breakage suppression properties of the wires (hereinafter, the property of suppressing wire breakage of the flexible wiring board and the property of making the flexible wiring board less likely to break are sometimes referred to as "wire breakage suppression properties").
Technical means for solving the technical problems
The technical scheme of the invention is as shown in [1] to [17 ].
[1] A cured product of a curable resin composition, wherein a free induction decay signal f (T) for determining the magnetization of a proton at a spin-spin relaxation time T2 is measured by a pulse nuclear magnetic resonance method at a measurement frequency of 20MHz, and when the free induction decay signal f (T) is approximated by the following expression, the value of [ A (1) ×T2 (1) +A (2) ×T2 (2) ] calculated from A (1), A (2), T2 (1) and T2 (2) in the following expression is 0.015ms or less, and T2 (3) is 0.50ms or more.
[ mathematics 1]
Wherein (offset) of item 4 of the above formula consisting of 4 items is an offset item; a (1), a (2), and a (3) in the above formulas are constants, respectively, and a (1) +a (2) +a (3) =1; t2 (1), T2 (2) and T2 (3) in the above formula are spin-spin relaxation times T2, respectively, and T2 (1) < T2 (2) < T2 (3); w (1), W (2) and W (3) in the above formula are each Weibull coefficients and are numbers of 1 to 2 inclusive; in the above formula, t is time, exp is an exponential function based on a naphal constant e.
[2] The cured product according to item [1] above, wherein the curable resin composition comprises: a polyurethane (a) having a functional group reactive with an epoxy group; a solvent (b); and an epoxy compound (c) having 2 or more epoxy groups in the molecule.
[3] The cured product according to item [2] above, wherein the polyurethane (a) has at least one of a first urethane structural unit and a second urethane structural unit; wherein the first urethane structural unit has at least one of a polyester structure and a polycarbonate structure; the second urethane structural unit has a carboxyl group.
[4] The cured product according to item [3] above, wherein the polyurethane (a) further has a third urethane structural unit, and wherein the third urethane structural unit has a fluorene structure.
[5] The cured product according to any one of the above [2] to [4], wherein the polyurethane (a) has a trans-1, 4-cyclohexanedimethylene group.
[6] The cured product according to any one of the above [2] to [5], wherein the polyurethane (a) has a number average molecular weight of 10000 to 50000.
[7] The cured product according to any one of the above [2] to [6], wherein the acid value of the polyurethane (a) is 10mgKOH/g or more and 70mgKOH/g or less.
[8] The cured product according to any one of the above [2] to [7], wherein the aromatic ring concentration of the polyurethane (a) is 0.1mmol/g or more and 5.0mmol/g or less.
[9] The cured product according to any one of the above [2] to [8], wherein the content of the solvent (b) is 25% by mass or more and 75% by mass or less relative to the total amount of the curable resin composition; the content ratio of the polyurethane (a) is 40 to 99 mass% based on the total amount of the polyurethane (a) and the epoxy compound (c).
[10] The cured product according to any one of the above [2] to [9], wherein the curable resin composition further contains at least one fine particle (d) selected from the group consisting of inorganic fine particles and organic fine particles.
[11] The cured product according to item [10] above, wherein the fine particles (d) comprise silica fine particles.
[12] The cured product according to item [10] above, wherein the fine particles (d) comprise hydrotalcite fine particles.
[13] The cured product according to any one of the above [10] to [12], wherein the content of the solvent (b) is 25% by mass or more and 75% by mass or less relative to the total amount of the curable resin composition; the content ratio of the fine particles (d) is 0.1 mass% or more and 60 mass% or less with respect to the total amount of the polyurethane (a), the solvent (b), the epoxy compound (c) and the fine particles (d); the content ratio of the polyurethane (a) is 40 to 99 mass% based on the total amount of the polyurethane (a) and the epoxy compound (c).
[14] A method for producing a cured product according to any one of the aspects [1] to [13], wherein the curable resin composition is cured by heat or active energy rays.
[15] A top-coating film comprising the cured product according to any one of the above-mentioned aspects [1] to [13 ].
[16] A flexible wiring board, wherein a portion of a surface of a flexible substrate on which wiring is formed is covered with the overcoat film described in the above [15 ].
[17] The flexible wiring board according to the item [16] above, wherein the wiring is a tin-plated copper wire.
Effects of the invention
The cured product, the overcoat film and the flexible wiring board according to the present invention have excellent low warpage and wire breakage inhibition properties.
Detailed Description
An embodiment of the present invention will be described below. The present embodiment shows an example of the present invention, and the present invention is not limited to the present embodiment. Further, the present embodiment may be modified or improved, and such modification or improvement is included in the scope of the present invention.
The inventors of the present invention have conducted intensive studies on a cured product obtained after curing a curable resin composition to solve the above problems, and as a result, have found that a cured product exhibiting a specific result of a free induction decay signal f (T) of a spin-spin relaxation time T2 of protons measured by a pulse nuclear magnetic resonance method has excellent low warpage and wire breakage inhibition of wirings, and have completed the present invention.
That is, the cured product of the present embodiment is a cured product of a curable resin composition, and the value of [ a (1) ×t2 (1) +a2 (2) ×t2 (2) ] calculated from a (1), a (2), T2 (1) and T2 (2) in the following expressions when the free induction decay signal f (T) for determining the magnetization of the proton is measured by the pulse nuclear magnetic resonance method at a measurement frequency of 20MHz and the free induction decay signal f (T) is approximated by the following expressions is 0.015ms or less and T2 (3) is 0.50ms or more. The value of [ A (1) ×T2 (1) +A (2) ×T2 (2) ] is preferably 0.002ms or more and 0.013ms or less. T2 (3) is preferably 0.70ms or more and 2.00ms or less.
[ math figure 2]
Wherein (offset) of item 4 of the above formula consisting of 4 items is an offset item; in addition, a (1), a (2), and a (3) in the above formulas are each constant, and a (1) +a (2) +a (3) =1; t2 (1), T2 (2) and T2 (3) in the above formula are spin-spin relaxation times T2, respectively, and T2 (1) < T2 (2) < T2 (3); further, W (1), W (2) and W (3) in the above formula are each weibull coefficients, and are numbers of 1 to 2 inclusive; in the above formula, t is time, exp is an exponential function based on a naphal constant e.
The approximation is obtained by synthesizing the free induction decay signal f (T) of the magnetization of the cured product with a curve of 3 different spin-spin relaxation times T2, and can be explained as follows. That is, items 1, 2 and 3 of the above formula are items showing properties of 3 components having relatively different molecular mobilities, and since T2 (1) < T2 (2) < T2 (3), they are shown in order from the component having low molecular mobility. Specifically, item 1 is an item indicating the property of a hard portion having low molecular mobility, item 3 is an item indicating the property of a soft portion having high molecular mobility, and item 2 is an item indicating the property of an intermediate portion between the hard portion and the soft portion.
That is, the characteristic of the cured product can be expressed by the above-described approximation by synthesizing the 3 components, with the 1 st term being the relatively fastest term and the 3 rd term being the relatively slowest term and the 2 nd term being the term of the velocity in the middle of the free induction decay signal f (t). In other words, the characteristics of the cured product are expressed by an approximation formula decomposed into the above 3 terms.
In the above formula, a (1), a (2), and a (3) are constants indicating the proportions of components in the hard portion, the intermediate portion, and the soft portion of the cured product. T2 (1), T2 (2), and T2 (3) in the above expression are spin-spin relaxation times T2 of the hard portion, the intermediate portion, and the soft portion. Further, W (1), W (2), and W (3) in the above expression are weibull coefficients of the hard portion, the intermediate portion, and the soft portion.
The cured product of the present embodiment has the above-described structure, and therefore has excellent low warpage and wire breakage inhibition properties. In addition, the overcoat film of the present embodiment containing the cured product of the present embodiment has excellent low warpage and wire breakage inhibition of the wiring. Further, the flexible wiring board of the present embodiment, in which the wiring-formed portion of the surface of the flexible substrate on which the wiring is formed is covered with the overcoat film of the present embodiment, also has excellent low warpage and wiring breakage inhibition properties.
In this embodiment, the free induction decay signal f (T) of magnetization measured by the pulse nuclear magnetic resonance method is approximated to obtain [ a (1) ×t2 (1) +a2 (2) ×t2 (2) ] and T2 (3). Since [ a (1) ×t2 (1) +a2×t2 (2) ] represents the property of the hard portion having low molecular mobility and the intermediate portion between the hard portion and the soft portion in the cured product, the smaller the value of [ a (1) ×t2 (1) +a2) ×t2 (2) ] is, the harder the structure of the hard portion in the cured product is represented. Further, the larger the value of T2 (3) indicating the property of the soft portion having high molecular mobility, the softer the structure of the soft portion in the cured product.
Conventionally, evaluation of cured products (overcoats) has been performed by measuring bending resistance, warpage, mechanical properties, and the like of the cured products. The bending resistance can be improved or the warpage can be reduced by changing the kind of the resin contained in the curable resin composition, but since this is a matrix type fumbling, a large amount of experience is required and it is not easy to design the function intentionally.
In the present invention, the components of the hard part and soft part constituting the molecular chain of the resin contained in the curable resin composition are evaluated quantitatively with respect to the relative content and the degree of softness thereof by the spin-spin relaxation time T2 obtained by the pulse nuclear magnetic resonance method, using the hard part and soft part in the cured product as the mechanical property index of the cured product.
Further, by making the hard portion and soft portion of the cured product harder, excellent low warpage properties and wire breakage inhibition properties can be imparted to the cured product and the overcoat film. The functions can be intentionally designed by combining conventional empirical methods through quantitative evaluation of hard and soft portions in the cured product.
The method for measuring the free induction decay signal f (T) for determining the magnetization of the proton at the spin-spin relaxation time T2 by the pulse nuclear magnetic resonance method is not particularly limited, and can be measured by the following method, for example. That is, the curable resin composition is applied to a substrate or the like in a film form, and is cured by heating at, for example, 120 to 150℃to obtain a film-like cured product having a thickness of, for example, 20. Mu.m. Then, the free induction decay signal f (T) for determining the magnetization of the spin-spin relaxation time T2 of the proton is measured by a pulse nuclear magnetic resonance method having a measurement frequency of 20MHz, for example, by a solid echo method.
The following is a description of a specific method for measuring the free induction decay signal f (T) for determining the magnetization of the spin-spin relaxation time T2 of protons by the pulse nuclear magnetic resonance method.
A specimen cut into a long strip of 3cm in length and several millimeters in width was used as a sample. The sample was placed in a glass sample tube having a diameter of 10mm so that the total mass was about 500mg, and the glass sample tube was mounted in a pulse nuclear magnetic resonance apparatus so that the sample was positioned at the coil portion of the pulse nuclear magnetic resonance apparatus. Next, the measurement was performed using a pulse nuclear magnetic resonance apparatus with hydrogen nuclei as measurement nuclei under measurement conditions of a measurement temperature of 40 ℃, a frequency of 20MHz, and a pulse width of 90 ° of 0.1 s. 3 samples were measured, and a free induction decay signal f (t) was obtained from the measurement results.
First, in order to determine the cyclic Delay (recovery Delay) =t1×5s in the parameters of the spin-spin relaxation time T2, the spin-lattice relaxation time T1 is obtained by the inversion recovery method (Inversion Recovery method). Examples of the measurement conditions of the spin-lattice relaxation time T1 are shown below.
Device Biospin the minispec mq by Bruker Co., ltd
Measuring frequency 20MHz
The temperature is 40 DEG C
Pulse procedure T1 reverse recovery method (Inversion Recovery method)
Initial pulse interval (First Pulse Separation) of 5ms
Final pulse interval (Final Pulse Separation): 1000ms
Cycle delay (1 s)
Gain (Gain) 95dB
Data Points (Data Points): 20
Delay sampling window (Delay Sampling Window) of 0.050ms
Sampling Window (Sampling Window) 0.020ms
Scanning (Scan) 16 times
Acquisition Scale (Acquisition scale): 0.3ms
The signal spectrum thus obtained is curve-fitted (Mono-exponential), and the spin-lattice relaxation time T1 is calculated. Then, based on the calculated spin-lattice relaxation time T1, a cyclic delay (cycle delay) =t1×5s is set, and a free induction decay signal f (T) for determining the magnetization of the spin-spin relaxation time T2 is measured. Examples of the measurement conditions of the spin-spin relaxation time T2 are shown below.
Device Biospin the minispec mq by Bruker Co., ltd
Measuring frequency 20MHz
The temperature is 40 DEG C
Pulse procedure T2 SOLID ECHO method (SOLID ECHO method)
Cycle delay (1 s)
Gain (Gain) 77dB
Data Points (Data Points): 100
Scanning (Scan) 16 times
Acquisition Scale (Acquisition scale): 0.3ms
The free induction Decay signal f (T) thus obtained was curve-fitted (7. Gauss-Decay extended), and the spin-spin relaxation time T2 was calculated. In curve fitting of the spin-spin relaxation time T2, an approximation function is obtained by arbitrarily changing the ratio of the exponential function/gaussian function, or the Abragamian function.
The spin-spin relaxation time T2 can be obtained by using the above mathematical expression as a fitted calculation expression. Fitting was performed in the range of decay time t from 0ms to 0.3 ms. At this time, the weibull coefficients are set to W (1) =2.0, W (2) =1.0, W (3) =1.0, and a (1), a (2), a (3), T2 (1), T2 (2), T2 (3), and offset of the above-described mathematical formulas are calculated.
Hereinafter, the cured product, the overcoat film, and the flexible wiring board according to the present embodiment will be described in more detail. First, a curable resin composition that produces a cured product according to the present embodiment by curing will be described.
I. Curable resin composition
The curable resin composition of the present embodiment is used for producing a flexible wiring board, in which a wiring-forming portion of a surface of a flexible substrate on which wiring is formed is covered with an overcoat film, and the overcoat film is formed from a cured product produced from the curable resin composition.
The curable resin composition of the present embodiment is not particularly limited as long as it contains a component that generates a cured product by curing with heat or active energy rays (e.g., ultraviolet rays, electron beams, X-rays), and preferably contains a curable resin.
For example, the curable resin composition of the present embodiment preferably contains polyurethane (a), solvent (b), and epoxy compound (c) having 2 or more epoxy groups in 1 molecule. The polyurethane (a), the solvent (b) and the epoxy compound (c) are described in detail below.
(I-1) polyurethane (a)
The type of the polyurethane (a) is not particularly limited as long as it has a functional group reactive with the epoxy group of the epoxy compound (c) and is cured by reaction with the epoxy compound (c). Examples of the functional group reactive with the epoxy group of the epoxy compound (c) include a urethane group (—nhcoo), a carboxyl group, an isocyanate group, a hydroxyl group, an amide group, and a cyclic acid anhydride group. The polyurethane (a) may have one or two or more of these functional groups. In addition, a cyclic acid anhydride group means an acid anhydride group formed by dehydration of two carboxyl groups in a molecule constitutes a part of a ring structure.
Among the functional groups listed above, carboxyl groups, isocyanate groups, amide groups, and cyclic acid anhydride groups are preferable in view of reactivity with epoxy groups possessed by the epoxy compound (c). Further, in view of the balance between the storage stability of the polyurethane (a) and the reactivity with the epoxy group of the epoxy compound (c), a carboxyl group and a cyclic acid anhydride group are more preferable, and a carboxyl group is further preferable. In view of easiness of introducing functional groups into polyurethane (a), urethane groups are preferred. The polyurethane (a) may have these functional groups at the molecular terminals or may have these functional groups in a form branched from the molecular chain.
The polyurethane (a) preferably has at least one of a first urethane structural unit and a second urethane structural unit in a molecule; wherein the first urethane structural unit has at least one of a polyester structure and a polycarbonate structure, and the second urethane structural unit has a carboxyl group.
In addition, the polyurethane (a) preferably has a third urethane structural unit in addition to at least one of the first urethane structural unit and the second urethane structural unit, wherein the third urethane structural unit has a fluorene structure.
Polyurethane (a) further preferably has trans 1, 4-cyclohexanedimethylene groups.
When the polyurethane (a) has the above urethane structural unit or trans-1, 4-cyclohexanedimethylene group, excellent low warpage properties and wire breakage inhibition properties of the overcoating film and flexible wiring board can be imparted.
The method for synthesizing the polyurethane (a) is not particularly limited, and examples thereof include a method in which a polyol compound having 2 or more hydroxyl groups in 1 molecule (for example, a diol compound) and a polyisocyanate compound having 2 or more isocyanate groups in 1 molecule (for example, a diisocyanate compound) are polymerized in a solvent in the presence or absence of a urethanization catalyst such as dibutyltin dilaurate. The polyol compound and the polyisocyanate compound may be used alone or in combination.
If necessary, the polymerization reaction may be carried out in the presence of at least one of a monohydroxy compound having 1 hydroxyl group in 1 molecule and a monoisocyanate compound having 1 isocyanate group in 1 molecule.
The polymerization reaction is preferably carried out in the absence of a catalyst or in the presence of a small amount of a catalyst to improve the long-term insulation reliability of the overcoat film described later.
The kind of the polyisocyanate compound is not particularly limited, and examples thereof include: cyclic aliphatic polyisocyanates, polyisocyanates having aromatic rings, chain aliphatic polyisocyanates, polyisocyanates having heterocyclic rings, and the like.
Examples of the cyclic aliphatic polyisocyanate include: 1, 3-cyclohexane diisocyanate, 1, 4-cyclohexane diisocyanate, isophorone diisocyanate, methylenebis (4-cyclohexyl isocyanate), 1, 3-bis (isocyanatomethyl) cyclohexane, 1, 4-bis (isocyanatomethyl) cyclohexane, (especially trans-1, 4-bis (isocyanatomethyl) cyclohexane), or a biuret of norbornene diisocyanate, norbornane diisocyanate, isophorone diisocyanate.
Examples of the polyisocyanate having an aromatic ring include: 2, 4-toluene diisocyanate, 2, 6-toluene diisocyanate, diphenylmethane-4, 4' -diisocyanate, 1, 3-xylyl diisocyanate, 1, 4-xylyl diisocyanate.
Examples of the chain aliphatic polyisocyanate include: biuret of hexamethylene diisocyanate, lysine triisocyanate, lysine diisocyanate, hexamethylene diisocyanate, 2, 4-trimethylhexamethylene diisocyanate, 2, 4-trimethylhexane methylene diisocyanate.
Examples of the polyisocyanate having a heterocyclic ring include: isocyanurate of isophorone diisocyanate and isocyanurate of hexamethylene diisocyanate.
These polyisocyanates may be used singly or in combination of two or more.
The kind of the diol compound is not particularly limited, and examples of the preferable diol compound include: polyester diol, polycarbonate diol, diol having carboxyl group in the molecule (hereinafter also referred to as "carboxyl group-containing diol"), diol having fluorene structure, diol having phenyl group or biphenyl group.
The polyester diol may be synthesized by esterification of a dicarboxylic acid and a diol. The polyester diol may be used alone or in combination of two or more.
Examples of the dicarboxylic acid include: phthalic acid, isophthalic acid, terephthalic acid, 3-methyl-benzene-1, 2-dicarboxylic acid, 4-methyl-benzene-1, 3-dicarboxylic acid, 5-methyl-benzene-1, 3-dicarboxylic acid, 2-methyl-benzene-1, 4-dicarboxylic acid, and the like. These dicarboxylic acids may be used singly or in combination of two or more.
Further, as the diol, for example, there may be mentioned: 1, 3-propanediol, 1, 2-propanediol, 1, 4-butanediol, 1, 5-pentanediol, 1, 6-hexanediol, 3-methyl-1, 5-pentanediol, 1, 8-octanediol, 1, 9-nonanediol, 2, 4-diethyl-1, 5-pentanediol, 2-ethyl-2-butyl-1, 3-propanediol, and the like. These diols may be used singly or in combination of two or more.
By using such a diol, the value of T2 (3) can be made larger.
Preferred dicarboxylic acids among the above dicarboxylic acids are phthalic acid, isophthalic acid, terephthalic acid, 3-methyl-benzene-1, 2-dicarboxylic acid, 4-methyl-benzene-1, 2-dicarboxylic acid, and particularly preferred is phthalic acid.
Among the above diols, preferred are 1, 3-propanediol, 1, 4-butanediol, 1, 5-pentanediol, 1, 6-hexanediol, 3-methyl-1, 5-pentanediol, and particularly preferred are 1, 6-hexanediol and 3-methyl-1, 5-pentanediol.
The number average molecular weight of the polyester diol is preferably 800 to 5000, more preferably 800 to 4000, and still more preferably 900 to 3500.
In addition, as the polyol compound, a low molecular weight polyol may be used. For example, 1, 2-propanediol, 1, 3-butanediol, 1, 4-butanediol, 3-methyl-1, 5-pentanediol, 1, 6-hexanediol, 1, 4-cyclohexanedimethanol, neopentyl glycol, diethylene glycol, dipropylene glycol, glycerol, trimethylolpropane, etc. can be used.
Polycarbonate diols may be synthesized by polycondensation of phosgene with diols. The polycarbonate diol may be used alone or in combination of two or more.
Since the diol suitable as a raw material for the polycarbonate diol is the same as the polyester diol, a description thereof will be omitted. Further, since the preferred number average molecular weight of the polycarbonate diol is the same as that of the polyester diol, a description thereof will be omitted.
The kind of the carboxyl group-containing diol is not particularly limited, and examples thereof include: dimethylolpropionic acid, 2-dimethylolbutyric acid, N, N-bis (hydroxyethyl) glycine, and the like. One of the carboxyl group-containing diols may be used alone, or two or more of them may be used in combination.
Among these carboxyl group-containing diols, 2-dimethylolpropionic acid and 2, 2-dimethylolbutyric acid are particularly preferable from the viewpoint of solubility in a reaction solvent in the production of polyurethane.
The kind of the diol having a fluorene structure is not particularly limited, and examples thereof include 9, 9-bis [4- (2-hydroxyethoxy) phenyl ] fluorene.
The kind of the diol having a phenyl group or a biphenyl group is not particularly limited, and examples thereof include 1, 1-dimethyl-bis [4- (2-hydroxyethoxy) phenyl ] methane, bis-4- (2-hydroxyethoxy) biphenyl, and 1, 1-bis [4- (2-hydroxyethoxy) phenyl ] cyclohexane.
In addition, in order to make the value of [ a (1) ×t2 (1) +a2) ×t2 (2) ] smaller, a diol having a high aromatic ring concentration is preferably used as the monomer for the polyurethane (a), and in order to make the value of T2 (3) larger, a diol having a high aliphatic concentration is preferably used as the monomer for the polyurethane (a).
Although the number average molecular weight of the polyurethane (a) is not particularly limited, in view of the ease of viscosity adjustment of the curable resin composition of the present embodiment described later, the number average molecular weight is preferably 7000 or more and 50000 or less, more preferably 7500 or more and 40000 or less, still more preferably 8000 or more and 30000 or less.
If the number average molecular weight is within the above range, the solvent solubility of the polyurethane (a) is good and the viscosity of the polyurethane solution is not easily increased, so that the curable resin composition described later is suitable for use in the production of an overcoat film or a flexible wiring board described later. Further, elongation, flexibility and strength of a cured product or an overcoat film to be described later are easily optimized.
The "number average molecular weight" herein is a polystyrene-equivalent number average molecular weight measured by gel permeation chromatography (hereinafter referred to as "GPC"). In addition, in the present specification, unless otherwise specified, measurement conditions of GPC are as follows.
Device name: HPLC unit HSS-2000 manufactured by Nippon light splitting Co., ltd
And (3) pipe column: shodex column LF-804X 3 (series connection) manufactured by Showa Denko Co., ltd.,
mobile phase: tetrahydrofuran (THF)
Flow rate: 1.0mL/min
A detector: RI-2031Plus manufactured by Nippon Spectrophotomy Co., ltd
Temperature: 40.0 DEG C
Sample amount: sample loop 100. Mu.L
Sample concentration: about 0.1 mass%
The acid value of the polyurethane (a) is not particularly limited, but is preferably 10 to 70mgKOH/g, more preferably 15 to 50mgKOH/g, still more preferably 20 to 35mgKO H/g.
When the acid value is within the above range, the polyurethane (a) has sufficient reactivity with the epoxy group. Therefore, in the curable resin composition described later, insufficient reactivity with other components such as the epoxy compound (c) having 2 or more epoxy groups in 1 molecule is less likely to occur, and therefore the heat resistance of the cured product of the curable resin composition is less likely to be lowered, and the cured product of the curable resin composition is not too hard and brittle. Further, it is easy to balance the solvent resistance of the overcoat film described later and the warpage of the flexible wiring board described later.
In the present specification, the acid value of polyurethane is an acid value measured by a potentiometric titration method defined in JIS K0070.
The aromatic ring concentration of the polyurethane (a) is not particularly limited, but is preferably 0.1 to 5.0 mmol/g, more preferably 0.5 to 4.5mmol/g, still more preferably 1.0 to 4.0 mmol/g.
When the aromatic ring concentration is within the above range, it is easy to balance between the solvent resistance of the overcoat film described later and the warpage of the flexible wiring board described later. Further, the value of [ A (1) ×T2 (1) +A (2) ×T2 (2) ] can be made smaller.
The aromatic ring concentration refers to the number (mole) of aromatic rings that 1g of the compound has. For example, if a polyurethane having a molecular weight of 438.5 repeating units (structural units) has 4 aromatic rings (e.g., phenyl groups) per 1 repeating unit, the aromatic ring concentration of the polyurethane is 9.12mmol/g (4×2.28mmol/1 g) because the number of repeating units in 1g of the polyurethane is 2.28 mmol.
The type of the aromatic ring is not particularly limited as long as it is a cyclic functional group having an aromaticity with a ring number of 3 or more, and examples thereof include: monocyclic aromatic hydrocarbon groups such as phenyl groups, polycyclic aromatic hydrocarbon groups such as biphenyl groups and fluorenyl groups, condensed cyclic aromatic hydrocarbon groups such as naphthyl groups and indenyl groups, and heteroaromatic hydrocarbon groups such as pyridyl groups.
However, in the case of a functional group having a plurality of cyclic structural sites, such as a polycyclic aromatic hydrocarbon group or a condensed cyclic aromatic hydrocarbon group, the number of aromatic rings is not 1, but the number of cyclic structural sites. For example, since a fluorenyl group has 2 benzene rings as cyclic structural sites, in the case of a polyurethane having 1 fluorenyl group per repeating unit, the number of aromatic rings that the polyurethane has is 2 per repeating unit.
Similarly, the number of aromatic rings is 2 in the case of biphenyl or naphthyl, 3 in the case of anthryl or phenanthryl, and 4 in the case of triphenylene or binaphthyl.
The aromatic ring concentration may be calculated from the ratio of the monomers, but may be calculated by 1 H-N MR、 13 After the structure of the polyurethane is determined by C-NMR, IR, etc., the method of using a catalyst comprising a catalyst selected from the group consisting of 1 The integration curve obtained by H-NMR analysis was calculated by comparing the number of protons from the aromatic ring with the number of protons from 1 repeating unit.
The polymerization reaction for synthesizing the polyurethane (a) may be carried out in a solvent, but in the case of carrying out in a solvent, the type of solvent used as the polymerization solvent is not particularly limited as long as it is a solvent capable of dissolving the polyurethane (a). Examples of the solvent used in the synthesis of the polyurethane (a) include: diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol ethyl methyl ether, diethylene glycol dibutyl ether, diethylene glycol butyl methyl ether, diethylene glycol isopropyl methyl ether, triethylene glycol dimethyl ether, triethylene glycol butyl methyl ether, tetraethylene glycol dimethyl ether, dipropylene glycol dimethyl ether, tripropylene glycol dimethyl ether, or an ether solvent such as ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, dipropylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether acetate, diethylene glycol monomethyl ether acetate, methyl methoxypropionate, ethyl methoxypropionate, methyl ethoxypropionate, an ester solvent such as γ -butyrolactone, or a hydrocarbon solvent such as decalin, or a ketone solvent such as cyclohexanone. These solvents may be used singly or in combination of two or more.
Among these solvents, in view of ease of adjusting the molecular weight of polyurethane and printability at the time of screen printing of a curable resin composition to be described later, γ -butyrolactone, diethylene glycol diethyl ether, diethylene glycol monoethyl ether acetate, diethylene glycol monomethyl ether acetate are preferred, γ -butyrolactone, diethylene glycol monoethyl ether acetate, diethylene glycol diethyl ether acetate are more preferred, and γ -butyrolactone alone, two mixed solvents of γ -butyrolactone and diethylene glycol monoethyl ether acetate, two mixed solvents of γ -butyrolactone and diethylene glycol diethyl ether, and three mixed solvents of γ -butyrolactone, diethylene glycol monoethyl ether acetate and diethylene glycol diethyl ether are more preferred.
The solid content concentration of the polyurethane (a) solution is preferably 10 mass% or more and 90 mass% or less, more preferably 15 mass% or more and 70 mass% or less, and still more preferably 20 mass% or more and 60 mass% or less, although not particularly limited. In the case of producing a curable resin composition to be described later using a solution of polyurethane (a) having a solid content of 20 mass% or more and 60 mass% or less, the viscosity of the solution of polyurethane (a) is preferably 5000mpa·s or more and million mpa·s or less under the measurement conditions of examples to be described later, from the viewpoint of uniform dispersion.
In addition, in the polymerization reaction for synthesizing the polyurethane (a), the order of charging the raw materials such as the monomer into the reaction vessel is not particularly limited, and for example, the raw materials may be charged in the following order. That is, after the diol compound is dissolved in the solvent in the reaction vessel, the diisocyanate compound is added to the reaction vessel in small amounts at 30 to 140 ℃, preferably at 60 to 120 ℃ and the monomers are reacted and polymerized at 50 to 160 ℃, preferably at 60 to 150 ℃.
The molar ratio of the monomers to be charged is adjusted according to the molecular weight and acid value of the polyurethane (a) to be targeted. In order to adjust the molecular weight of polyurethane (a), a monohydroxy compound may be used as a raw material of polyurethane (a). In this case, by the above-described method, when the molecular weight of the polyurethane in polymerization reaches the target number average molecular weight (or is close to the target number average molecular weight), a monohydroxy compound is added to block the isocyanate groups at the molecular terminals of the polyurethane in polymerization to suppress further increase in the number average molecular weight.
In the case of using a monohydroxy compound, the total number of isocyanate groups contained in the total raw material of polyurethane (a) may be smaller, the same or larger than the total number of hydroxyl groups contained in the total raw material of polyurethane (a) minus the total number of hydroxyl groups contained in the monohydroxy compound (i.e., the total number of hydroxyl groups contained in a compound having 2 or more hydroxyl groups in 1 molecule as the raw material of polyurethane (a)).
Although unreacted monohydroxy compound remains as a result in the case where an excessive amount of monohydroxy compound is used, in this case, the excessive monohydroxy compound may be directly used as a part of the solvent or may be removed by distillation or the like.
The monohydroxy compound is used as a raw material of the polyurethane (a) in order to suppress an increase in molecular weight of the polyurethane (a) (i.e., stop the polymerization reaction), and the monohydroxy compound is added to the reaction solution in small amounts successively at a temperature of 30 to 150 ℃, preferably 70 to 140 ℃ inclusive, and then kept at the above temperature to complete the reaction.
In order to adjust the molecular weight of the polyurethane (a), a monoisocyanate compound may be used as a raw material of the polyurethane (a). In this case, in order to form hydroxyl groups at the molecular terminals of the polyurethane (a) when the monoisocyanate compound is added, it is necessary that the total number of isocyanate groups obtained by subtracting the total number of isocyanate groups of the monoisocyanate compound from the total number of isocyanate groups of the total raw material of the polyurethane (a) (that is, the total number of isocyanate groups of the compound having 2 or more isocyanate groups in 1 molecule as the raw material of the polyurethane (a)) is smaller than the total number of hydroxyl groups of the total raw material of the polyurethane (a).
When the reaction of the hydroxyl groups of the total raw material of the polyurethane (a) with the isocyanate groups of the diisocyanate compound is substantially completed, the hydroxyl groups remaining at the molecular terminals of the polyurethane (a) during production are reacted with the isocyanate groups of the monoisocyanate compound. For this reason, in the process of producing polyurethane, the temperature of the polyurethane solution is controlled to 30 ℃ to 150 ℃, preferably 70 ℃ to 140 ℃ and then a monoisocyanate compound is added to the polyurethane solution in small amounts successively, and then the reaction is completed while maintaining the above temperature.
In the production of polyurethane (a), the blending amounts of the respective components of the raw materials are preferably as follows. The ratio of the total number of hydroxyl groups of the diol compound as the raw material of polyurethane (a) to the total number of isocyanate groups of the diisocyanate compound as the raw material of polyurethane (a) is preferably hydroxyl group: isocyanate group=1:0.9 to 0.9:1, more preferably hydroxyl group: isocyanate group=1:0.92 to 0.92:1.
(I-2) solvent (b)
The type of the solvent (b) which is one of the essential components of the curable resin composition of the present embodiment is not particularly limited as long as the polyurethane (a) can be dissolved, and examples thereof include: ether solvents such as diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol ethyl methyl ether, diethylene glycol dibutyl ether, diethylene glycol butyl methyl ether, diethylene glycol isopropyl methyl ether, triethylene glycol dimethyl ether, triethylene glycol butyl methyl ether, tetraethylene glycol dimethyl ether, dipropylene glycol dimethyl ether, and tripropylene glycol dimethyl ether.
The solvent (b) may be: ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, dipropylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether acetate, diethylene glycol monomethyl ether acetate, methyl methoxypropionate, ethyl methoxypropionate, methyl ethoxypropionate, ethyl ethoxypropionate, gamma-butyrolactone, and the like.
Further, as the solvent (b), hydrocarbon solvents such as decalin and ketone solvents such as cyclohexanone can be mentioned.
These solvents may be used singly or in combination of two or more.
Among these solvents, in view of balance between printability at the time of screen printing and volatility of the solvent, γ -butyrolactone, diethylene glycol diethyl ether, diethylene glycol monoethyl ether acetate, diethylene glycol monomethyl ether acetate, more preferably γ -butyrolactone, diethylene glycol monoethyl ether acetate, diethylene glycol diethyl ether, further preferably a single solvent of γ -butyrolactone, two mixed solvents of γ -butyrolactone and diethylene glycol monoethyl ether acetate, two mixed solvents of γ -butyrolactone and diethylene glycol diethyl ether, and three mixed solvents of γ -butyrolactone, diethylene glycol monoethyl ether acetate and diethylene glycol diethyl ether.
These preferable combinations of solvents are suitable as solvents for screen printing inks.
The solvent (b) contained in the curable resin composition of the present embodiment may be partially or entirely used as a solvent for synthesis used in the production of the polyurethane (a), and is thus advantageous in the production of the curable resin composition of the present embodiment, and is preferable in terms of process.
The content of the solvent (b) in the curable resin composition of the present embodiment is preferably 25% by mass or more and 75% by mass or less, more preferably 35% by mass or more and 65% by mass or less, relative to the total amount of the curable resin composition of the present embodiment. The total amount of the curable resin composition of the present embodiment is the total amount of the polyurethane (a), the solvent (b), and the epoxy compound (c) having 2 or more epoxy groups in 1 molecule. However, when the curable resin composition of the present embodiment contains other components such as fine particles (d) described later, the total amount of the curable resin composition of the present embodiment refers to the total amount of the polyurethane (a), the solvent (b), the epoxy compound (c) having 2 or more epoxy groups in 1 molecule, the fine particles (d), and other components.
When the content of the solvent (b) is in the range of 25 mass% to 75 mass% with respect to the total amount of the curable resin composition of the present embodiment, the viscosity of the curable resin composition is favorable for printing by the screen printing method, and the extent of diffusion due to bleeding of the curable resin composition after screen printing is small. As a result, the actual print area of the curable resin composition is not likely to be larger than the portion to be coated with the curable resin composition (i.e., the shape of the printing plate), and is therefore suitable.
(I-3) an epoxy compound (c) having 2 or more epoxy groups in the molecule 1
An epoxy compound (c), which is one of essential components of the curable resin composition of the present embodiment, reacts with a functional group such as a carboxyl group or a hydroxyl group of the polyurethane (a), and functions as a curing agent in the curable resin composition. Since the functional groups such as carboxyl groups and hydroxyl groups of the polyurethane (a) are reactive with epoxy groups, they react with epoxy groups of the epoxy compound (c).
The type of the epoxy compound (c) is not particularly limited as long as it is a compound having 2 or more epoxy groups in 1 molecule, and examples thereof include novolac-type epoxy resins obtained by epoxidizing novolac resins, and specific examples thereof include phenol novolac-type epoxy resins, o-cresol novolac-type epoxy resins, and the like.
The novolak resin is a resin obtained by condensing or co-condensing phenols such as phenol, cresol, xylenol, resorcinol, catechol, and the like, naphthols such as α -naphthol, β -naphthol, and dihydroxynaphthalene, and compounds having an aldehyde group such as formaldehyde, acetaldehyde, propionaldehyde, benzaldehyde, and salicylaldehyde, with an acidic catalyst.
Further, examples of the epoxy compound (c) having 2 or more epoxy groups in 1 molecule include diglycidyl ethers of phenols and glycidyl ethers of alcohols. Examples of the phenols include bisphenol a, bisphenol F, bisphenol S, alkyl-substituted or unsubstituted diphenols, and stilbene phenols. Namely, the diglycidyl ethers of these phenols are bisphenol a type epoxy compound, bisphenol F type epoxy compound, bisphenol S type epoxy compound, biphenyl type epoxy compound, stilbene type epoxy compound. Examples of the alcohol include butanediol, polyethylene glycol, and polypropylene glycol.
Examples of the epoxy compound (c) having 2 or more epoxy groups in 1 molecule include glycidyl ester type epoxy resins of carboxylic acids such as phthalic acid, isophthalic acid and tetrahydrophthalic acid, glycidyl type or methylglycidyl type epoxy resins of compounds in which active hydrogen bonded to nitrogen atoms is substituted with glycidyl groups such as aniline, bis (4-aminophenyl) methane and isocyanuric acid, glycidyl type or methylglycidyl type epoxy resins of compounds in which active hydrogen bonded to nitrogen atoms is substituted with glycidyl groups such as p-aminophenol and active hydrogen bonded to nitrogen atoms and phenolic hydroxyl groups are substituted with glycidyl groups.
Further, examples of the epoxy compound (c) having 2 or more epoxy groups in 1 molecule include: alicyclic epoxy resins such as vinylcyclohexene diepoxide, 3, 4-epoxycyclohexylmethyl-3, 4-epoxycyclohexane carboxylate, and 2- (3, 4-epoxyyl) cyclohexyl-5, 5-spiro (3, 4-epoxyyl) cyclohexane-m-dioxane. These alicyclic epoxy resins are obtained by epoxidizing an olefin bond of an alicyclic hydrocarbon compound having an olefin bond in the molecule.
Further, examples of the epoxy compound (c) having 2 or more epoxy groups in 1 molecule include: glycidyl ethers of para-xylene and/or meta-xylene modified phenol resins, glycidyl ethers of terpene modified phenol resins, glycidyl ethers of dicyclopentadiene modified phenol resins, glycidyl ethers of cyclopentadiene modified phenol resins, glycidyl ethers of polycyclic aromatic ring modified phenol resins, glycidyl ethers of naphthalene ring-containing phenol resins.
Further, examples of the epoxy compound (c) having 2 or more epoxy groups in 1 molecule include: halogenated phenol novolac type epoxy resins, hydroquinone type epoxy resins, trimethylolpropane type epoxy resins, linear aliphatic epoxy resins (obtained by oxidizing an olefin bond of a linear aliphatic hydrocarbon compound having an olefin bond in a molecule with a peracid such as peracetic acid), and diphenylmethane type epoxy resins.
Further, examples of the epoxy compound (c) having 2 or more epoxy groups in 1 molecule include: epoxide of aralkyl type phenol resin such as phenol aralkyl resin and naphthol aralkyl resin, epoxy resin containing sulfur atom, or tricyclo [5.2.1.0 2，6 ]Diglycidyl ether of decanedimethanol, or an epoxy resin having an adamantane structure. As examples of the epoxy resin having an adamantane structure, there may be mentioned: 1, 3-bis (1-adamantyl) -4, 6-bis (glycidyl) benzene, 1- [2',4' -bis (glycidyl) phenyl]Adamantane, 1, 3-bis (4 ' -glycidylphenyl) adamantane and 1, 3-bis [2',4' -bis (glycidylphenyl) adamantane]Adamantane, and the like.
These epoxy compounds (c) may be used singly or in combination of two or more.
Among these epoxy compounds (c), an epoxy compound having 2 or more epoxy groups in 1 molecule and having an aromatic ring structure and/or an alicyclic structure is preferable.
In the case where importance is attached to the long-term insulating property of the cured product of the present embodiment described later, from the viewpoint of obtaining a cured product having a low water absorption rate, among the epoxy compounds having 2 or more epoxy groups in 1 molecule and having an aromatic ring structure and/or alicyclic structure, compounds having 2 or more epoxy groups in 1 molecule and having a tricyclodecane structure and an aromatic ring structure are preferable.
Specific examples of the compound having 2 or more epoxy groups in 1 molecule and having a tricyclodecane structure and an aromatic ring structure include: glycidyl ethers of dicyclopentadiene modified phenolic resins (i.e., 1 molecule having more than 2 epoxy groups and having a tricyclo [ 5.2.1.0) 2，6 ]Decane structure and aromatic ring structure), or 1, 3-bis (1-adamantyl) -4, 6-bis (glycidyl) benzene, 1- [2',4' -bis (glycidyl) phenyl]Adamantane, 1, 3-bis (4 ' -glycidylphenyl) adamantane, and 1, 3-bis [2',4' -bis (glycidylphenyl)]An epoxy resin having an adamantane structure (i.e., having 2 or more epoxy groups in 1 molecule and having tricyclo [ 3.3.1.1) 3，7 ]Decane structure and aromatic ring structure), or a compound represented by the following chemical formula (1). Among them, the compound represented by the following chemical formula (1) is particularly preferable. In the following chemical formula (1), k is preferably an integer of 1 to 10.
[ chemical formula 1]
On the other hand, in the case where importance is attached to the reactivity with polyurethane, among the epoxy compounds having 2 or more epoxy groups in 1 molecule and having an aromatic ring structure and/or an alicyclic structure, compounds having 2 or more epoxy groups in 1 molecule and having an amino group and an aromatic ring structure are preferable.
Specific examples of the compound having 2 or more epoxy groups in 1 molecule and having an amino group and an aromatic ring structure include: glycidyl-type or methylglycidyl-type epoxy resins of compounds in which active hydrogen bonded to nitrogen atoms is substituted with glycidyl groups, which are contained in aniline or bis (4-aminophenyl) methane, or glycidyl-type or methylglycidyl-type epoxy resins of compounds in which active hydrogen bonded to nitrogen atoms and active hydrogen contained in phenolic hydroxyl groups are substituted with glycidyl groups, respectively; or a compound represented by the following chemical formula (2). Among them, the compound represented by the following chemical formula (2) is particularly preferable.
[ chemical formula 2]
In the curable resin composition of the present embodiment, the preferable content of the epoxy compound (c) relative to the content of the polyurethane (a) varies depending on the amount of the functional group (for example, carboxyl group) capable of reacting with an epoxy group of the polyurethane (a), and thus cannot be said to be a general one.
However, the ratio of the number of functional groups capable of reacting with epoxy groups ([ the number of functional groups capable of reacting with epoxy groups ]/[ the number of epoxy groups ]) of the polyurethane (a) to the number of epoxy groups of the epoxy compound (c) is preferably in the range of 1/3 to 2/1, more preferably in the range of 1/2.5 to 1.5/1.
When the ratio is in the range of 1/3 to 2/1, the curable resin composition of the present embodiment does not leave a large amount of unreacted epoxy compound and also does not leave a large amount of functional groups capable of reacting with epoxy groups, and the functional groups capable of reacting with epoxy groups and the epoxy groups in the epoxy compound can react in a good balance when cured.
The content ratio of the epoxy compound (c) is preferably 1 mass% or more and 60 mass% or less, more preferably 2 mass% or more and 50 mass% or less, and still more preferably 3 mass% or more and 40 mass% or less, with respect to the total amount of the polyurethane (a) and the epoxy compound (c) in the curable resin composition of the present embodiment. That is, the content ratio of the polyurethane (a) is preferably 40 mass% or more and 99 mass% or less, more preferably 50 mass% or more and 98 mass% or less, and still more preferably 60 mass% or more and 97 mass% or less, with respect to the total amount of the polyurethane (a) and the epoxy compound (c) in the curable resin composition of the present embodiment.
When the content ratio of the epoxy compound (c) is 1 mass% or more and 60 mass% or less relative to the total amount of the polyurethane (a) and the epoxy compound (c), a balance can be achieved between the low warpage property of the flexible wiring board described later and the wire breakage suppression property of the wire, which will be described later, of the overcoating film.
(I-4) microparticles (d)
At least one type of fine particles (d) selected from the group consisting of inorganic fine particles and organic fine particles may be added to the curable resin composition of the present embodiment.
Examples of the inorganic fine particles include: silicon dioxide (SiO) 2 ) Alumina (Al) 2 O 3 ) Titanium dioxide (TiO) 2 ) Tantalum oxide (Ta) 2 O 5 ) Zirconium dioxide (ZrO) 2 ) Silicon nitride (Si) 3 N 4 ) Barium titanate (BaO. TiO) 2 ) Barium carbonate (BaCO) 3 ) Lead titanate (PbO. TiO) 2 ) Lead zirconate titanate (PZT), lanthanum lead zirconate titanate (PLZT), gallium oxide (Ga) 2 O 3 ) Spinel (MgO. Al) 2 O 3 ) Mullite (Al) 2 O 3 2SiO 2), cordierite (2MgO.2Al 2 O 3 ·5SiO 2 ) Talc (3MgO.4SiO) 2 ·H 2 O), aluminum Titanate (TiO) 2 -Al 2 O 3 ) Yttria-containing zirconium dioxide (Y) 2 O 3 -ZrO 2 ) Barium silicate (BaO.8SiO) 2 ) Boron Nitride (BN), calcium carbonate (CaCO) 3 ) Calcium sulfate (CaSO) 4 ) Zinc oxide (ZnO), magnesium titanate (MgO. TiO) 2 ) Barium sulfate (BaSO) 4 ) The organic bentonite, carbon (C), hydrotalcite, etc., may be used singly or in combination of two or more.
The organic fine particles are preferably heat-resistant resin fine particles having an amide bond, an imide bond, an ester bond, or an ether bond. Examples of such resins may be exemplified by polyimide resins or precursors thereof, polyamideimide resins or precursors thereof, or polyamide resins from the viewpoints of heat resistance and mechanical properties.
Among these fine particles, silica fine particles and hydrotalcite fine particles are preferable, and the curable resin composition of the present embodiment preferably contains at least one selected from the group consisting of silica fine particles and hydrotalcite fine particles.
The silica fine particles used in the curable resin composition of the present embodiment may be in the form of powder, and may be silica fine particles having a coating on the surface or silica fine particles subjected to chemical surface treatment with an organic compound.
The silica fine particles used in the curable resin composition of the present embodiment are not particularly limited as long as they are dispersed in the curable resin composition to form a paste, and examples thereof include AEROSIL (trade name) available from AEROSIL corporation of japan. Silica fine particles represented by AEROSIL (trade name) are useful for imparting printability to a curable resin composition at the time of screen printing, in which case the purpose is to impart thixotropic properties.
Hydrotalcite fine particles used in the curable resin composition of the present embodiment are prepared by mixing Mg with hydrotalcite fine particles 6 Al 2 (O H) 16 CO 3 ·4H 2 O, etc., and is a lamellar inorganic compound. Furthermore, hydrotalcites can also be obtained synthetically, e.g. Mg 1-x Al x (OH) 2 (CO 3 ) x/2 ·mH 2 O and the like can be obtained by synthesis. Namely, hydrotalcite is a layered Mg/Al compound, and can fix chloride ions (Cl) by ion exchange with carbonate groups between layers - ) And/or sulfate ion (SO) 4 2- ) Is an anion of (a). With this function, chloride ions (Cl) causing migration of copper and tin can be trapped - ) And sulfate ion (SO) 4 2- ) The long-term insulation reliability of the cured product is improved.
As commercially available hydrotalcite, STABIACE HT-1, STABIACE HT-7, STABIACE HT-P of Sasa chemical industry Co., ltd, DHT-4A, DHT-4A2, DHT-4C of Kagaku chemical industry Co., ltd, etc. can be cited.
The mass average particle diameter of the inorganic fine particles and the organic fine particles is preferably 0.01 to 10. Mu.m, more preferably 0.1 to 5. Mu.m.
The content of the fine particles (d) in the curable resin composition of the present embodiment is preferably 0.1 mass% or more and 60 mass% or less, more preferably 0.5 mass% or more and 40 mass% or less, and still more preferably 1 mass% or more and 20 mass% or less, with respect to the total amount of the polyurethane (a), the solvent (b), the epoxy compound (c) and the fine particles (d).
When the content of the fine particles (d) in the curable resin composition of the present embodiment is within the above-described range, the viscosity of the curable resin composition is advantageous for printing by the screen printing method, and the extent of diffusion due to bleeding of the curable resin composition after screen printing is small. As a result, the actual print area of the curable resin composition is not likely to be larger than the portion to be coated with the curable resin composition (i.e., the shape of the printing plate), and is therefore suitable.
Further, when the curable resin composition of the present embodiment contains the fine particles (d), the content of the solvent (b) in the curable resin composition of the present embodiment is preferably 25 mass% or more and 75 mass% or less, more preferably 30 mass% or more and 75 mass% or less, and still more preferably 35 mass% or more and 70 mass% or less, with respect to the total amount of the curable resin composition of the present embodiment, that is, the total amount of the polyurethane (a), the solvent (b), the epoxy compound (c) and the fine particles (d).
When the content of the solvent (b) is in the range of 25 mass% to 75 mass% with respect to the total amount of the curable resin composition of the present embodiment, the viscosity of the curable resin composition is favorable for printing by the screen printing method, and the extent of diffusion due to bleeding of the curable resin composition after screen printing is small. As a result, the actual printing area of the curable resin composition is not easily larger than the portion to be coated with the curable resin composition (i.e., the shape of the printing plate), and in addition, screen printing has good printability (good release property, etc.).
Even when the curable resin composition of the present embodiment contains the fine particles (d), the content of the polyurethane (a) is preferably 1 to 60 mass%, more preferably 2 to 50 mass%, and even more preferably 3 to 40 mass% based on the total amount of the polyurethane (a) and the epoxy compound (c) in the curable resin composition of the present embodiment. That is, the content ratio of the polyurethane (a) is preferably 40 mass% or more and 99 mass% or less, more preferably 50 mass% or more and 98 mass% or less, and still more preferably 60 mass% or more and 97 mass% or less, with respect to the total amount of the polyurethane (a) and the epoxy compound (c) in the curable resin composition of the present embodiment.
Even when the curable resin composition of the present embodiment contains the fine particles (d), when the content ratio of the polyurethane (a) is 1 mass% or more and 60 mass% or less with respect to the total amount of the polyurethane (a) and the epoxy compound (c), a balance can be achieved between the low warpage property of the flexible wiring board to be described later and the wire breakage inhibition property of the wiring, which are coated with the overcoat film to be described later.
(I-5) curing accelerator (e)
The curable resin composition of the present embodiment may further contain a curing accelerator (e). The type of the curing accelerator is not particularly limited as long as it is a compound capable of promoting the reaction between a functional group such as a carboxyl group of the polyurethane (a) and an epoxy group of the epoxy compound (c), but when the functional group is a carboxyl group, the following compounds are exemplified.
That is, examples of the curing accelerator include: triazine compounds such as melamine, acetoguanamine, benzoguanamine, 2, 4-diamino-6-methacryloxyethyl-s-triazine, 2, 4-diamino-6-vinyl-s-triazine, and 2, 4-diamino-6-vinyl-s-triazine-isocyanuric acid adducts.
Further, as examples of the curing accelerator, there may be mentioned: imidazole, 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1-benzyl-2-methylimidazole, 2-phenyl-4-methylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-aminoethyl-2-methylimidazole, 1- (cyanoethylaminoethyl) -2-methylimidazole, N- [2- (2-methyl-1-imidazolyl) ethyl ] urea, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-methylimidazolium trimellitate, 1-cyanoethyl-2-ethyl-4-methylimidazolium trimellitate, 1-cyanoethyl-2-undecylium trimellitate, 2, 4-diamino-6- [2' -methylimidazole- (1 ') -ethyl-2, 4' -triazinyl) 2, 4' -diamino-6- [2' -methylimidazole-s-triazine, 1' -amino-2- (2-ethyl-6 ' -triazinyl) 2-undecylimidazole, 4-diamino-6- [2' -ethyl-4 ' -methylimidazolyl- (1 ') ] -ethyl-s-triazine, 1-dodecyl-2-methyl-3-benzylimidazolium chloride, N ' -bis (2-methyl-1-imidazolylethyl) urea, N, N ' -bis (2-methyl-1-imidazolylethyl) adipamide, 2-phenyl-4-methyl-5-hydroxymethyl imidazole, 2-phenyl-4, 5-dimethylol imidazole, 2-methylimidazole isocyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2, 4-diamino-6- [2' -methylimidazole- (1 ') ] -ethyl-s-triazine isocyanuric acid adduct, 2-methyl-4-formylimidazole, 2-ethyl-4-methyl-5-formylimidazole, 2-phenyl-4-methylformylimidazole, 1-benzyl-2-phenylimidazole, 1, 2-dimethylimidazole, 1- (2-hydroxyethyl) imidazole, vinylimidazole, 1-methylimidazole, 1-allylimidazole, 2-ethylimidazole, 2-butylimidazole, 2-butyl-5-hydroxymethyl imidazole, 2, 3-dihydro-1H-pyrrolo [1,2-a ] benzimidazole, imidazole compounds such as 1-benzyl-2-phenylimidazole hydrogen bromide and 1-dodecyl-2-methyl-3-benzylimidazolium chloride.
Further, as examples of the curing accelerator, cyclic amidine compounds such as diazabicycloalkene and salts thereof, and derivatives thereof can be cited. Examples of diazabicycloolefins include 1, 5-diazabicyclo (4.3.0) nonene-5 and 1, 8-diazabicyclo (5.4.0) undecene-7.
Further, as examples of the curing accelerator, there may be mentioned: organic phosphine compounds such as triphenylphosphine, diphenyl (p-tolyl) phosphine, tris (alkylphenyl) phosphine, tris (alkoxyphenyl) phosphine, tris (alkyl alkoxyphenyl) phosphine, tris (dialkylphenyl) phosphine, tris (trialkylphenyl) phosphine, tris (tetraalkylphenyl) phosphine, tris (dialkoxyphenyl) phosphine, tris (trialkoxyphenyl) phosphine, tris (tetraalkoxyphenyl) phosphine, trialkylphosphine, dialkylarylphosphine, and alkyldiarylphosphine.
Further, as examples of the curing accelerator, there may be mentioned amine compounds such as triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, tris (dimethylaminomethyl) phenol, and the like, or dicyandiamide.
These curing accelerators may be used singly or in combination of two or more.
Among these curing accelerators, melamine, imidazole compounds, cyclic amidine compounds and derivatives thereof, phosphine compounds, and amine compounds are preferable, melamine, 1, 5-diazabicyclo (4.3.0) nonene-5 and salts thereof, and 1, 8-diazabicyclo (5.4.0) undecene-7 and salts thereof are more preferable, in view of the effect of curing acceleration and electrical insulating properties of the cured product of the present embodiment to be described later.
The content of the curing accelerator (e) in the curable resin composition of the present embodiment is not particularly limited as long as the curing accelerator effect can be exhibited, but the curing accelerator (e) is blended in a range of preferably 0.05 to 5 parts by mass, more preferably 0.1 to 3 parts by mass, based on 100 parts by mass of the total amount of the polyurethane (a) and the epoxy compound (c), from the viewpoints of curability of the curable resin composition of the present embodiment and electrical insulation properties or water resistance of the cured product and overcoat film of the present embodiment described later.
When the content of the curing accelerator (e) in the curable resin composition of the present embodiment is within the above range, the curable resin composition of the present embodiment can be cured in a short time, and the electrical insulating properties and water resistance of the cured product or the overcoat film of the present embodiment, which will be described later, can be improved.
(I-6) other Components
In the curable resin composition of the present embodiment, various additives may be added in addition to the fine particles (d) and the curing accelerator (e). The following describes additives that can be incorporated into the curable resin composition of the present embodiment.
Since a cured product having good electrical insulation properties can be obtained by curing the curable resin composition of the present embodiment, the curable resin composition of the present embodiment can be used, for example, as a composition for an insulating protective resist ink for wiring. When the curable resin composition of the present embodiment is used as a composition of a resist ink for insulation protection of wiring (i.e., a composition for forming an overcoat film of a flexible wiring board), an antifoaming agent (f) may be added to prevent or suppress generation of bubbles at the time of printing.
The type of defoaming agent is not particularly limited as long as it can prevent or inhibit the occurrence of bubbles when the curable resin composition of the present embodiment is printed and coated on the surface of a flexible substrate in the production of a flexible wiring board.
That is, as examples of the defoaming agent, there may be mentioned: an acrylic polymer-based antifoaming agent such as BYK-077 (manufactured by BYK Chemie, japan Co., ltd.), SN antifoaming agent 470 (manufactured by San Nopco Co., ltd.), TSA750S (manufactured by Momentiv e Performance Materials Co., ltd.), silicone oil SH-203 (manufactured by Tolye Dow Corning Co., ltd.), acetylene glycol-based antifoaming agent such as Dappo SN-348 (manufactured by San Nopco Co., ltd.), D appo SN-354 (manufactured by San Nopco Co., ltd.), dappo SN-368 (manufactured by San Nopco Co., ltd.), DISPARLON 230HF (manufactured by Nanyaka Co., ltd.), surfynol DF-110D (manufactured by Surfynol chemical Co., ltd.), surfynol DF-37 (manufactured by Surfynol chemical Co., ltd.), or fluorine-containing silicone-based antifoaming agent such as FA-630.
The content of the antifoaming agent (f) in the curable resin composition of the present embodiment is not particularly limited, and the antifoaming agent component (f) is preferably blended in a range of 0.01 to 5 parts by mass, more preferably in a range of 0.05 to 4 parts by mass, and even more preferably in a range of 0.1 to 3 parts by mass, based on 100 parts by mass of the total amount of the polyurethane (a), the solvent (b), the epoxy compound (c) and the fine particles (d).
Further, if necessary, a surfactant such as a leveling agent, or a colorant such as phthalocyanine blue, phthalocyanine green, iodine green, disazo yellow, crystal violet, carbon black, naphthalene black, or the like may be added to the curable resin composition of the present embodiment.
In addition, when it is necessary to suppress oxidative deterioration of the polyurethane (a) and discoloration upon heating, it is preferable to add an antioxidant such as a phenol antioxidant, a phosphite antioxidant, or a thioether antioxidant to the curable resin composition of the present embodiment.
Further, a flame retardant or lubricant may be added to the curable resin composition of the present embodiment, as necessary.
The curable resin composition of the present embodiment is obtained by uniformly kneading and mixing a part or all of the compounding ingredients (i.e., polyurethane (a), solvent (b), epoxy compound (c), fine particles (d), etc.) in a roll mill, bead mill, etc. When only a part of the compounding ingredients is mixed, the remaining ingredients may be mixed when the curable resin composition of the present embodiment is actually used.
< viscosity of curable resin composition >
The curable resin composition of the present embodiment preferably has a viscosity of 10000 to 100000 mPas, more preferably 20000 to 60000 mPas at 25 ℃.
In the present specification, the viscosity of the curable resin composition of the present embodiment at 25℃is a viscosity measured after 7 minutes from the start of rotation using a cone/plate viscometer (model DV-II+Pro, spindle model C PE-52, manufactured by Brookfield Co., ltd.) at a rotation speed of 10 rpm.
Thixotropic index of curable resin composition
When the curable resin composition of the present embodiment is used as a composition of a resist ink for insulation protection of wiring (i.e., an overcoat agent for a flexible wiring board), the thixotropic index of the curable resin composition of the present embodiment is preferably set within a certain range in order to improve the printability of the curable resin composition of the present embodiment.
When the curable resin composition of the present embodiment is used as an overcoat agent for a flexible wiring board, the thixotropic index of the curable resin composition of the present embodiment is preferably 1.1 or more, more preferably 1.1 or more and 3.0 or less, and still more preferably 1.1 or more and 2.5 or less, in order to improve the printability (for example, printability in screen printing) of the curable resin composition of the present embodiment.
When the curable resin composition of the present embodiment is used as an overcoat agent for a flexible wiring board, the thixotropic index of the curable resin composition of the present embodiment is in the range of 1.1 to 3.0, the curable resin composition of the present embodiment after printing is less likely to flow, and a film shape of a certain thickness can be maintained, so that a printed pattern is easily maintained.
As a method for adjusting the thixotropic index of the curable resin composition to 1.1 or more, there are a method of adjusting the thixotropic index using the above-mentioned inorganic fine particles or organic fine particles, a method of adjusting the thixotropic index using a polymer additive, and the like, but a method of adjusting the thixotropic index using inorganic fine particles or organic fine particles is preferable.
In the present specification, the thixotropic index of the curable resin composition according to the present embodiment is the ratio of the viscosity measured at 25℃at a rotational speed of 1rpm to the viscosity measured at 25℃at a rotational speed of 10rpm ([ viscosity at a rotational speed of 1rpm ]/[ viscosity at a rotational speed of 10rpm ]). These viscosities can be measured using a cone/plate viscometer (model DV-II+Pro, spindle model CPE-52, manufactured by Brookfield Corp.).
II. cured product
The cured product of the present embodiment is a cured product obtained by curing the curable resin composition of the present embodiment. The method of curing the curable resin composition of the present embodiment is not particularly limited, and the curable resin composition may be cured by heat or active energy rays (e.g., ultraviolet rays, electron rays, or X-rays). Therefore, a polymerization initiator such as a thermal radical generator or a photo radical generator may be added to the curable resin composition of the present embodiment.
The cured product of the present embodiment can be used as an insulating protective film (overcoat film). In particular, for example, the cured product of the present embodiment can be used as an insulating protective film for wiring by coating all or part of the wiring of a flexible wiring board such as a Chip on film.
When the overcoat film containing the cured product of the present embodiment is formed on the surface of the flexible substrate, a flexible wiring board excellent in both low warpage and wire breakage inhibition properties can be formed. Further, the cured product of the present embodiment is low in stringiness and excellent in defoaming property, and therefore can be produced with excellent handleability and productivity. Further, the cured product of the present embodiment has excellent low warpage, flexibility, and moisture resistance, and also has excellent long-term insulation reliability. Further, the cured product of the present embodiment has good adhesion to a substrate such as a flexible substrate. Further, the surface of the cured product of the present embodiment is less likely to cause a sticking phenomenon (tack phenomenons).
III, overcoat film, flexible wiring board, and method for producing the same
The overcoat film according to the present embodiment is a film containing the cured product according to the present embodiment, and can be produced by curing the curable resin composition according to the present embodiment. Specifically, the overcoating film of the present embodiment can be produced by disposing the curable resin composition of the present embodiment in a film form on all or part of the surface of the flexible substrate on which the wiring is formed, which part is to be formed with the wiring, and then curing the film-like curable resin composition by heating or the like to form a film-like cured product. The overcoat film of the present embodiment is suitable for use as an overcoat film of a flexible wiring board.
The flexible wiring board according to the present embodiment is a flexible wiring board in which all or part of the wiring formed on the surface of the flexible substrate on which the wiring is formed is covered with an overcoat film.
The flexible wiring board of the present embodiment can be manufactured from the curable resin composition of the present embodiment and the flexible substrate. Specifically, the flexible wiring board of the present embodiment can be produced by disposing the curable resin composition of the present embodiment in a film form on all or part of the surface of the flexible substrate on which the wiring is formed, which part is to be formed with the wiring, and then curing the film-like curable resin composition to form a film-like cured product. In addition, the wiring covered by the overcoat film is preferably a tin-plated copper wire in view of oxidation resistance and economy of the wiring.
An example of a method for producing the overcoat film and the flexible wiring board according to the present embodiment will be described below. The overcoat film and the flexible wiring board can be formed by the following steps 1, 2 and 3.
(step 1) a printing step of printing the curable resin composition of the present embodiment on at least a part of a wiring pattern portion of a flexible substrate to form a printed film on the wiring pattern portion.
(step 2) a solvent removal step of removing the printed film obtained in step 1 by evaporating part or all of the solvent in the printed film in an atmosphere of 40 to 100 ℃.
(step 3) a curing step of curing the printed film obtained in step 1 or the printed film obtained in step 2 by heating at a temperature of 100 to 170 ℃ to form an overcoat film.
The printing method of the curable resin composition in step 1 is not particularly limited, and the curable resin composition of the present embodiment may be coated on a flexible substrate by, for example, screen printing, roll coating, spray coating, curtain coating, or the like, to obtain a printed film.
Step 2 is performed as needed, and step 3 may be performed immediately after step 1, and the curing reaction and the solvent removal may be performed simultaneously in step 3. In the case of performing step 2, the temperature is preferably 40 ℃ to 100 ℃, more preferably 60 ℃ to 100 ℃, still more preferably 70 ℃ to 90 ℃ in view of the evaporation rate of the solvent and rapid transfer to the heat curing operation. In step 3 or step 2, the evaporation time of the solvent is not particularly limited, but is preferably 10 minutes to 120 minutes, more preferably 20 minutes to 100 minutes.
The heat curing temperature in step 3 is preferably 105 to 160 ℃, more preferably 110 to 150 ℃, from the viewpoint of preventing the diffusion of the plating layer and imparting low warpage and flexibility to the overcoat layer suitable as a protective film. Although the time for performing the heat curing in the step 3 is not particularly limited, it is preferably 10 minutes to 150 minutes, more preferably 15 minutes to 120 minutes.
By the above method, a flexible wiring board covered with an overcoat film on all or part of the wiring formed on the surface of the flexible substrate on which the wiring is formed can be obtained. Since the thus obtained overcoat film is excellent in flexibility and pliability, the flexible wiring board of the present embodiment is also excellent in flexibility and pliability, and disconnection of wiring is less likely to occur even if the flexible wiring board is shaken (excellent in disconnection-suppressing property of wiring). Therefore, the flexible wiring board according to the present embodiment is less likely to crack, and is suitable for flexible printed wiring boards used in, for example, a Chip on film (Chip on film) technology.
Further, since the curable resin composition of the present embodiment is not easily shrunk when cured, the flexible wiring board of the present embodiment has a small warpage amplitude. Therefore, in the step of mounting the IC chip on the flexible wiring board according to the present embodiment, the mounting position of the IC chip is easily positioned. Further, since the long-term insulation reliability of the overcoat film is excellent, the long-term insulation reliability of the flexible wiring board of the present embodiment is also excellent.
Examples
Hereinafter, the present invention will be described in detail with reference to examples and comparative examples.
< Synthesis of polyester diol (reference Synthesis example 1) >)
To a reaction vessel equipped with a stirrer, a thermometer and a condenser equipped with a distiller, 983.5g (6.74 mol) of phthalic anhydride and 879.2g (7.44 mol) of 1, 6-hexanediol were added, the inside of the reaction vessel was warmed to 140℃using an oil bath, and stirring was continued for 4 hours. Then, while continuing to stir, 1.74g of mono-n-butyltin oxide was added.
Then, the internal temperature of the reaction vessel was slowly raised while gradually lowering the pressure in the reaction vessel by a vacuum pump, and water was discharged to the outside of the reaction vessel by distillation under reduced pressure. Finally, the internal temperature was raised to 220℃and the pressure was reduced to 133.32Pa. After 15 hours, it was confirmed that water was not distilled off at all, and the reaction was completed.
The hydroxyl value of the resulting polyester diol was measured and found to be 53.1mgKOH/g.
< Synthesis of polyurethane >
Example 1
To a reaction vessel equipped with a stirring device, a thermometer and a condenser, 122.1g of polyester diol (POLYLITE (registered trademark) OD-X-2900, hydroxyl value 53.4mgKOH/g, polyester diol made from 1, 6-hexanediol and phthalic anhydride) as a raw material, 12.9g of 2, 2-dimethylolpropionic acid (made from Japanese chemical Co., ltd.) as a carboxyl group-containing diol, 9-bis [4- (2-hydroxyethoxy) phenyl ] fluorene (made from Osaka gas chemical Co., ltd., trade name BPEF) as a diol other than polyester diol and carboxyl group-containing diol) as a polyester diol (made from Mitsubishi chemical Co., ltd.) as a solvent (203.5 g of gamma-butyrolactone as a solvent) were charged, and all the raw materials were dissolved by heating to 100 ℃.
After the temperature of the reaction solution was lowered to 90 ℃, 20.9g of trans-1, 4-bis (isocyanatomethyl) cyclohexane (FORTIMO (registered trademark) manufactured by Sanyo chemical Co., ltd.) as a diisocyanate compound, 28.3g of dicyclohexylmethane-4, 4' -diisocyanate (manufactured by Sanyo chemical Co., ltd.) was dropped by a dropping funnel over a period of 30 minutes.
After the reaction was allowed to proceed at 120℃for 8 hours, it was confirmed by infrared spectroscopy (IR) that absorption by C=O stretching vibration of the isocyanate group was hardly observed, 1.7g of methylethyloxime (manufactured by Kagaku Co., ltd.) was added dropwise to the reaction solution, and the reaction was allowed to proceed at 80℃for 3 hours. Accordingly, a solution containing a polyurethane having a carboxyl group (hereinafter referred to as "polyurethane solution A1") was obtained. After the polyurethane solution A1 was cooled to room temperature, 44.7g of gamma-butyrolactone and 43.8g of diethylene glycol diethyl ether were added thereto to adjust the viscosity.
The viscosity of the polyurethane solution A1 obtained was 133000 mPas. The number average molecular weight (Mn) of the polyurethane having a carboxyl group (hereinafter referred to as "polyurethane AU 1") contained in the polyurethane solution A1 was 8000, the weight average molecular weight (Mw) was 74000, the z average molecular weight (Mz) was 658600, and the parameter Mz/Mw indicating the molecular weight distribution range was 8.9. The acid value of polyurethane AU1 was 25.0mgKOH/g. The aromatic ring concentration was 3.21mmol/g. Further, the solid content concentration in the polyurethane solution A1 was 40.5 mass%.
Example 2 of the embodiment
To a reaction vessel equipped with a stirring device, a thermometer and a condenser, 112.0g of polyester diol (POLYLITE (registered trademark) OD-X-2900, hydroxyl value 53.4mgKOH/g, polyester diol using 1, 6-hexanediol and phthalic anhydride as raw materials) 11.8g of 2, 2-dimethylolpropionic acid (manufactured by Nippon chemical Co., ltd.), 9-bis [4- (2-hydroxyethoxy) phenyl ] fluorene (manufactured by Osaka gas chemical Co., ltd., trade name BPEF) 9.79g, fluorene group-containing diol (manufactured by Osaka gas chemical Co., ltd., trade name BPEF-9) 19.62g, and gamma-butyrolactone EO (manufactured by Mitsubishi chemical Co., ltd.) as a solvent were added, and all the raw materials were dissolved by heating to 100 ℃.
[ chemical formula 3]
After the temperature of the reaction solution was lowered to 90 ℃, 51.8g of methylenebis (4-cyclohexylisocyanate) (DESMODUR-W (trade name) manufactured by Kagaku Bayer Urethane Co., ltd.) as a diisocyanate compound was dropped from a dropping funnel over a period of 30 minutes.
After the reaction was allowed to proceed at 120℃for 8 hours, it was confirmed by infrared spectroscopy (IR) that absorption by C=O stretching vibration of the isocyanate group was hardly observed, 1.7g of methylethyloxime (manufactured by Kagaku Co., ltd.) was added dropwise to the reaction solution, and the reaction was allowed to proceed at 80℃for 3 hours. Accordingly, a solution containing a polyurethane having a carboxyl group (hereinafter referred to as "polyurethane solution A2") was obtained. After the polyurethane solution A2 was cooled to room temperature, 45.1g of gamma-butyrolactone and 43.8g of diethylene glycol diethyl ether were added thereto to adjust the viscosity.
The viscosity of the polyurethane solution A2 obtained was 131000 mPas. The number average molecular weight (Mn) of the polyurethane having a carboxyl group (hereinafter referred to as "polyurethane AU 2") contained in the polyurethane solution A2 was 10000, the weight average molecular weight (Mw) was 61000, the z average molecular weight (Mz) was 359900, and the parameter Mz/Mw indicating the molecular weight distribution range was 5.9. The acid value of polyurethane AU2 was 23.9mgKOH/g. The aromatic ring concentration was 2.51mmol/g. Further, the solid content concentration in the polyurethane solution A2 was 42.5 mass%.
Example 3
Into a reaction vessel equipped with a stirring device, a thermometer and a condenser, 112.9g of polyester diol (POLYLITE (registered trademark) OD-X-2900, hydroxyl value 53.4mgKOH/g, polyester diol made from 1, 6-hexanediol and phthalic anhydride), 12.8g of 2, 2-dimethylolpropionic acid (made from Japanese chemical Co., ltd.) as a carboxyl group-containing diol, 20.4g of 1, 1-dimethyl-Bis [4- (2-hydroxyethoxy) phenyl ] methane (Bis-A-2 EO made from Ming and chemical Co., ltd.) as a diol other than the polyester diol, and 204.7g of gamma-butyrolactone (made from Mitsubishi chemical Co., ltd.) as a solvent were charged, and all the materials were dissolved by heating to 100 ℃.
After the temperature of the reaction solution was lowered to 90 ℃, 58.6g of methylenebis (4-cyclohexylisocyanate) (DESMODUR-W (trade name) manufactured by Kagaku Bayer Urethane Co., ltd.) as a diisocyanate compound was dropped from a dropping funnel over a period of 30 minutes.
After the reaction was allowed to proceed at 120℃for 8 hours, it was confirmed by infrared spectroscopy (IR) that absorption by C=O stretching vibration of the isocyanate group was hardly observed, 2.0g of methylethyloxime (manufactured by Kagaku Co., ltd.) was added dropwise to the reaction solution, and the reaction was allowed to proceed at 80℃for 3 hours. Accordingly, a solution containing a polyurethane having a carboxyl group (hereinafter referred to as "polyurethane solution A3") was obtained. After the polyurethane solution A3 was cooled to room temperature, 45.5g of gamma-butyrolactone and 43.8g of diethylene glycol diethyl ether were added thereto to adjust the viscosity.
The viscosity of the polyurethane solution A3 obtained was 150000 mPa.s. The polyurethane having a carboxyl group (hereinafter referred to as "polyurethane AU 3") contained in the polyurethane solution A3 had a number average molecular weight (Mn) of 12000, a weight average molecular weight (Mw) of 57000, and a z average molecular weight (Mz) of 221730, and thus, a parameter Mz/Mw indicating a molecular weight distribution range was calculated to be 3.89. The acid value of polyurethane AU3 was 24.8mgKOH/g. The aromatic ring concentration was 2.73mmol/g. Further, the solid content concentration in the polyurethane solution A3 was 44.5 mass%.
Example 4
To a reaction vessel equipped with a stirring device, a thermometer and a condenser, 110.6g of polyester diol (POLYLITE (registered trademark) OD-X-2900, hydroxyl value 53.4mgKOH/g, polyester diol made from 1, 6-hexanediol and phthalic anhydride), 12.9g of 2, 2-dimethylolpropionic acid (made from Japanese chemical Co., ltd.) as a carboxyl group-containing diol, 20.0g of bis-4- (2-hydroxyethoxy) biphenyl (BP-2 EO made from Mimo chemical Co., ltd.) as a diol other than polyester diol and carboxyl group-containing diol, and 204.6g of gamma-butyrolactone (made from Mitsubishi chemical Co., ltd.) as a solvent were added, and all the materials were dissolved by heating to 100 ℃.
After the temperature of the reaction solution was lowered to 90 ℃, 61.1g of methylenebis (4-cyclohexylisocyanate) (DESMODUR-W (trade name) manufactured by Kagaku Bayer Urethane Co., ltd.) as a diisocyanate compound was dropped from a dropping funnel over a period of 30 minutes.
After the reaction was allowed to proceed at 120℃for 8 hours, it was confirmed by infrared spectroscopy (IR) that absorption by C=O stretching vibration of the isocyanate group was hardly observed, 2.1g of methylethyloxime (manufactured by Kagaku Co., ltd.) was added dropwise to the reaction solution, and the reaction was allowed to proceed at 80℃for 3 hours. Accordingly, a solution containing a polyurethane having a carboxyl group (hereinafter referred to as "polyurethane solution A4") was obtained. After the polyurethane solution A4 was cooled to room temperature, 45.6g of gamma-butyrolactone and 43.8g of diethylene glycol diethyl ether were added thereto to adjust the viscosity.
The viscosity of the resulting polyurethane solution A4 was 166000 mPas. The polyurethane having a carboxyl group (hereinafter referred to as "polyurethane AU 4") contained in the polyurethane solution A4 had a number average molecular weight (Mn) of 12600, a weight average molecular weight (Mw) of 59000, and a z average molecular weight (Mz) of 248390, and thus, a parameter Mz/Mw indicating a molecular weight distribution range was calculated to be 4.21. The acid value of polyurethane AU4 was 25.1mgKOH/g. The aromatic ring concentration was 2.77mmol/g. Further, the solid content concentration in the polyurethane solution A4 was 41.2 mass%.
Example 5
To a reaction vessel equipped with a stirring device, a thermometer and a condenser, 114.4g of polyester diol (POLYLITE (registered trademark) OD-X-2900, hydroxyl value 53.4mgKOH/g, polyester diol made from 1, 6-hexanediol and phthalic anhydride) as a raw material, 12.9g of 2, 2-dimethylolpropionic acid (made from Japanese chemical Co., ltd.) as a carboxyl group-containing diol, 20.5g of 1, 1-Bis [4- (2-hydroxyethoxy) phenyl ] cyclohexane (Bis-Z-2 EO made from Ming. Chemical Co., ltd.) as a polyester diol and a diol other than carboxyl group-containing diol) as a raw material, and 204.8g of gamma-butyrolactone (made from Mitsubishi chemical Co., ltd.) as a solvent were charged, and all the raw materials were dissolved by heating to 100 ℃.
After the temperature of the reaction solution was lowered to 90 ℃, 57.0g of methylenebis (4-cyclohexylisocyanate) (DESMODUR-W (trade name) manufactured by Kagaku Bayer Urethane Co., ltd.) as a diisocyanate compound was dropped from a dropping funnel over a period of 30 minutes.
After the reaction was allowed to proceed at 120℃for 8 hours, it was confirmed by infrared spectroscopy (IR) that absorption by C=O stretching vibration of the isocyanate group was hardly observed, 2.0g of methylethyloxime (manufactured by Kagaku Co., ltd.) was added dropwise to the reaction solution, and the reaction was allowed to proceed at 80℃for 3 hours. Accordingly, a solution containing a polyurethane having a carboxyl group (hereinafter referred to as "polyurethane solution A5") was obtained. After the polyurethane solution A5 was cooled to room temperature, 45.4g of gamma-butyrolactone and 43.8g of diethylene glycol diethyl ether were added thereto to adjust the viscosity.
The viscosity of the polyurethane solution A5 obtained was 106000 mPas. The number average molecular weight (Mn) of the polyurethane having a carboxyl group (hereinafter referred to as "polyurethane AU 5") contained in the polyurethane solution A5 was 8300, the weight average molecular weight (Mw) was 95000, the z average molecular weight (Mz) was 263150, and the parameter Mz/Mw indicating the molecular weight distribution range was 2.77. The acid value of polyurethane AU5 was 24.7mgKOH/g. The aromatic ring concentration was 2.69mmol/g. Further, the solid content concentration in the polyurethane solution A5 was 38.7 mass%.
Example 6
To a reaction vessel equipped with a stirring device, a thermometer and a condenser, 121.5g of polyester diol (POLYLITE (registered trademark) HS-2H-209P, a polyester diol having a hydroxyl value of 28.8mgKOH/g and using 1, 6-hexanediol and phthalic anhydride as raw materials), 12.9g of 2, 2-dimethylolpropionic acid (manufactured by Nippon chemical Co., ltd.) as a carboxyl group-containing diol, 9-bis [4- (2-hydroxyethoxy) phenyl ] fluorene (manufactured by Osaka gas chemical Co., ltd., trade name BPEF) as a diol other than polyester diol and carboxyl group-containing diol) were added, and 203.2g of gamma-butyrolactone (manufactured by Mitsubishi chemical Co., ltd.) as a solvent was heated to 100℃to dissolve all the raw materials.
After the temperature of the reaction solution was lowered to 90 ℃, 48.6g of methylenebis (4-cyclohexylisocyanate) (DESMODUR-W (trade name) manufactured by Kagaku Bayer Urethane Co., ltd.) as a diisocyanate compound was dropped from a dropping funnel over a period of 30 minutes.
After the reaction was allowed to proceed at 120℃for 8 hours, it was confirmed by infrared spectroscopy (IR) that absorption by C=O stretching vibration of the isocyanate group was hardly observed, 1.7g of methylethyloxime (manufactured by Kagaku Co., ltd.) was added dropwise to the reaction solution, and the reaction was allowed to proceed at 80℃for 3 hours. Accordingly, a solution containing a polyurethane having a carboxyl group (hereinafter referred to as "polyurethane solution A6") was obtained. After the polyurethane solution A6 was cooled to room temperature, 45.0g of gamma-butyrolactone and 43.8g of diethylene glycol diethyl ether were added thereto to adjust the viscosity.
The viscosity of the resulting polyurethane solution A6 was 123000 mPas. The number average molecular weight (Mn) of the polyurethane having a carboxyl group (hereinafter referred to as "polyurethane AU 6") contained in the polyurethane solution A6 was 10500, the weight average molecular weight (Mw) was 89000, the z average molecular weight (Mz) was 335530, and the parameter Mz/Mw indicating the molecular weight distribution range was 3.77. The acid value of polyurethane AU6 was 25.1mgKOH/g. The aromatic ring concentration was 1.64mmol/g. Further, the solid content concentration in the polyurethane solution A6 was 41.2 mass%.
Example 7
< Synthesis of polyester diol >
To a reaction vessel equipped with a stirrer, a thermometer and a Libi condenser capable of distilling off water as a by-product of the reaction, 98.7g of 1, 6-hexanediol (manufactured by Kuraray Co., ltd.), 109.6g of 9, 9-bis [4- (2-hydroxyethoxy) phenyl ] fluorene (manufactured by Osaka gas chemical Co., ltd., trade name: BPEF), and 154.1g of hexahydrophthalic anhydride (manufactured by Mitsubishi gas chemical Co., ltd.) were charged, and the inside temperature of the reaction vessel was raised to 210℃using an oil bath to dissolve all the raw materials.
After the reaction was continued at 210℃for 4 days while removing water as a by-product, when the amount of distilled water reached 18g, the temperature was lowered to 120℃and the reaction was stopped. Thus, polyester diol PE1 having a fluorene skeleton was obtained.
The hydroxyl value of the resulting polyester diol PE1 was measured and found to be 60.0mgKOH/g. Accordingly, the number average molecular weight of the polyester diol PE1 was 3360.
(Synthesis of polyurethane)
Into a reaction vessel equipped with a stirring device, a thermometer and a condenser, 93.1g of the above-mentioned polyester diol PE1 (hydroxyl value: 60.0 mgKOH/g), 7.5g of 2, 2-dimethylolpropionic acid (manufactured by Nippon chemical Co., ltd.) as a carboxyl group-containing diol, 125.0g of gamma-butyrolactone (manufactured by Mitsubishi chemical Co., ltd.) as a solvent were charged, and all the raw materials were dissolved by heating to 100 ℃.
After the temperature of the reaction solution was lowered to 90 ℃, 23.3g of methylenebis (4-cyclohexylisocyanate) (DESMODUR-W (trade name) manufactured by Kagaku Bayer Urethane Co., ltd.) as a diisocyanate compound was dropped from a dropping funnel over a period of 30 minutes.
After the reaction was allowed to proceed at 120℃for 8 hours, it was confirmed by infrared spectroscopy (IR) that absorption by C=O stretching vibration of the isocyanate group was hardly observed, 1.1g of methylethyloxime (manufactured by Kagaku Co., ltd.) was added dropwise to the reaction solution, and the reaction was allowed to proceed at 80℃for 3 hours. Accordingly, a solution containing a polyurethane having a carboxyl group (hereinafter referred to as "polyurethane solution A7") was obtained. After the polyurethane solution A7 was cooled to room temperature, 27.9g of gamma-butyrolactone and 27.0g of diethylene glycol diethyl ether were added thereto to adjust the viscosity.
The viscosity of the polyurethane solution A7 obtained was 77000 mPas. The number average molecular weight (Mn) of the polyurethane having a carboxyl group (hereinafter referred to as "polyurethane AU 7") contained in the polyurethane solution A7 was 12000, the weight average molecular weight (Mw) was 78000, the z average molecular weight (Mz) was 399360, and the parameter Mz/Mw indicating the molecular weight distribution range was 5.12. The acid value of polyurethane AU7 was 25.0mgKOH/g. The aromatic ring concentration was 1.88mmol/g. Further, the solid content concentration in the polyurethane solution A7 was 43.2 mass%.
The data for polyurethanes AU1 to AU7 are summarized in Table 1.
TABLE 1
(determination of acid value)
The method for measuring the acid value of the polyurethane obtained by synthesis will be described. The solvent in the polyurethane solution was distilled off under reduced pressure under heating to obtain polyurethane, and the acid value was measured by a potentiometric titration method defined in JIS K0070. For example, an automatic potential difference titration apparatus AT-510 and a composite glass electrode C-173 manufactured by Kyoto electronic industries, inc. can be used to measure the acid value by the potential difference titration method.
(determination of number average molecular weight, weight average molecular weight, and z-average molecular weight of polyurethane)
The number average molecular weight, weight average molecular weight and z average molecular weight of the polyurethane obtained by synthesis are the number average molecular weight (Mn), weight average molecular weight (Mw) and z average molecular weight (Mz) in terms of polystyrene measured by GPC. GPC measurement conditions were as described above.
(measurement of viscosity of polyurethane solution)
The viscosity of the polyurethane solution was measured using a cone/plate viscometer (model DV-II+Pro, spindle model CPE-52, manufactured by Brookfield Co.) at a temperature of 25.0℃and a rotation speed of 5 rpm. The measured value is the viscosity measured after 7 minutes from the start of spindle rotation. In addition, about 0.8g of polyurethane solution was used in the measurement of viscosity.
< preparation of Main agent Complex >
160.0 parts by mass of polyurethane liquid A1 having a solid content of 40% adjusted by adding gamma-butyrolactone, 6.3 parts by mass of silica fine particles (trade name: AEROSIL R-974, manufactured by AEROSIL Co., ltd.), 0.72 parts by mass of melamine (manufactured by Nissan chemical Co., ltd.) as a curing accelerator, and 8.4 parts by mass of diethylene glycol diethyl ether were mixed using a three-roll mill (manufactured by Nissan chemical Co., ltd., model S-4 3/4X 11). To this was added 2.0 parts by mass of an antifoaming agent (trade name TSA750S, manufactured by Momentive Performance Materials Co., ltd.) and mixed with a spatula (spatula), thereby obtaining a main agent complex C1.
The main agent complexes C2 to C7 were obtained by the same procedure as the main agent complex C1, except that the type of the polyurethane solution was changed from the polyurethane solution A1 to any one of the polyurethane solutions A2 to A7.
Production of curing agent solution
Preparation of curing agent solution example 1
To a vessel equipped with a stirrer, a thermometer and a condenser, 16.85 parts by mass of an epoxy compound represented by the above chemical formula (2) (grade name JER, epoxy equivalent 120g/eqv, manufactured by Mitsubishi chemical corporation) and 18.25 parts by mass of diethylene glycol diethyl ether were added, and the temperature inside the vessel was raised to 40 ℃ while stirring, and then stirring was continued for 30 minutes. After confirming complete dissolution of the epoxy compound, the solution was cooled to room temperature to obtain an epoxy compound solution having a concentration of 48 mass%. The epoxy compound solution was used as the curing agent solution E1.
Preparation of curing agent solution example 2
To a vessel equipped with a stirrer, a thermometer and a condenser, 21.66 parts by mass of cyclohexanedimethanol epoxy resin (grade name: showree (registered trademark) CDMDG, epoxy equivalent 126 g/eqv) and 18.25 parts by mass of diethylene glycol diethyl ether were added, and the temperature inside the vessel was raised to 40℃while stirring, and then stirring was continued for 30 minutes. After confirming complete dissolution of the epoxy compound, the solution was cooled to room temperature to obtain an epoxy compound solution having a concentration of 48 mass%. The epoxy compound solution was used as the curing agent solution E2.
Preparation of curing agent solution example 3
To a vessel equipped with a stirrer, a thermometer and a condenser, 15.47 parts by mass of cyclohexanedimethanol epoxy resin (grade name: showree (registered trademark) PETG, epoxy equivalent 90 g/eqv) and 18.25 parts by mass of diethylene glycol diethyl ether were added, and the temperature inside the vessel was raised to 40℃while stirring, and then stirring was continued for 30 minutes. After confirming complete dissolution of the epoxy compound, the solution was cooled to room temperature to obtain an epoxy compound solution having a concentration of 48 mass%. The epoxy compound solution was used as the curing agent solution E3.
Production of curable resin composition
90 parts by mass of the main agent complex C1 and 4.0 parts by mass of the curing agent solution E1 were added to a plastic container, and 5.0 parts by mass of diethylene glycol diethyl ether and 1.5 parts by mass of diethylene glycol diethyl ether acetate as solvents were added thereto. The mixture was stirred at room temperature for 5 minutes using a spatula (spatula) to obtain a curable resin composition F1.
Curable resin compositions F2 to F7 (see table 2) were obtained in the same manner as the curable resin composition F1 except that any one of the main-agent complexes C2 to C7 was used instead of the main-agent complex C1. Curable resin compositions F8 and F9 were obtained in the same manner as the curable resin composition F1 except that the curing agent solution E2 or the curing agent solution E3 was used instead of the curing agent solution E1 (see table 2).
TABLE 2
Further, 700 parts by mass of FREX SOLD ER MASK NPR (registered trademark) -3400A (corresponding to a main agent complex) manufactured by Nippon Polytech Co., ltd.) and 120 parts by mass of curing agent HARDENER NPR (registered trademark) -3400B (corresponding to a curing agent solution) manufactured by Nippon Polytech Co., ltd.) were mixed to obtain a curable resin composition G1.
Further, 100 parts by mass of SN-9000F A (corresponding to a main agent complex) manufactured by Hitachi chemical Co., ltd.) and 10 parts by mass of a curing agent SN-9000F B (corresponding to a curing agent solution) manufactured by Hitachi chemical Co., ltd were mixed to obtain a curable resin composition G2.
The above-mentioned NPR-3400A, B and SN-9000FA, B are commercially available curable compositions for forming an overcoat film of a flexible wiring board.
< evaluation of overcoat film and Flexible Wiring Board >
Flexible wiring boards having overcoat films (examples 1 to 9 and comparative examples 1 and 2) were produced using the curable resin compositions F1 to F9 and G1 and G2, and flexibility, wire breakage inhibition property, warpage property and long-term insulation reliability were evaluated.
(evaluation of flexibility)
The curable resin composition was applied to copper of a flexible copper-clad laminate (manufactured by Sumitomo Metal mining Co., ltd., grade: SPERFLEX, copper thickness: 8 μm, polyimide thickness: 38 μm) by screen printing so that the width was 75mm, the length was 110mm, and the thickness of the cured coating film was 15 μm. After the flexible copper clad laminate printed with the curable resin composition was kept at room temperature for 10 minutes, it was put into a hot air circulation dryer at 120 ℃ for 60 minutes to cure the curable resin composition.
After peeling the PET film of the flexible copper-clad laminate backing, a test piece having a width of 10mm was cut with a cutter. The test piece was bent at about 180 degrees so that the film on which the cured product was formed faced outward, and compressed using a compressor at a pressure of 0.5±0.2MPa for 3 seconds. Then, the bent portion of the test piece was enlarged by 30 times with a microscope in a state where the bent portion of the test piece was bent, and the cured film was observed to confirm whether or not cracks were generated. The results are shown in Table 2.
(evaluation of wire breakage inhibitory Property of Wiring)
A flexible wiring board was manufactured by etching a flexible copper clad laminate (manufactured by sumitomo metal mine co., ltd., grade name: speclex US, copper thickness: 8 μm, polyimide thickness: 38 μm) to obtain a substrate having a fine comb pattern shape (copper wiring width/copper wiring interval=15 μm/15 μm) as described in JPCA-ET01 of the standard of the general corporate japan electronic circuit industry (JPCA), and further subjecting the substrate having the fine comb pattern shape to a tin plating treatment.
Then, a curable resin composition is applied to the flexible wiring board by a screen printing method. The film thickness of the printed curable resin composition was 10 μm after drying the film of the curable resin composition on the polyimide surface.
The flexible wiring board thus obtained was placed in a hot air circulation dryer at a temperature of 80 ℃ for 30 minutes, and then placed in a hot air circulation dryer at a temperature of 120 ℃ for 120 minutes, whereby a film of the curable resin composition formed on the flexible wiring board was cured. Next, using the test piece, MIT test was performed by the method described in JIS C5016 to evaluate the breaking inhibition of the wiring of the flexible wiring board. The test conditions for the MIT test are as follows:
testing machine: MIT Tester BE202 manufactured by Tester industry Co., ltd
Bending speed: 10 times/min
Load is as follows: 200g of
Bending angle: + -90 DEG
Radius of clamp front end: 0.5mm
The MIT test was performed under the above test conditions, and the presence or absence of cracks in the wiring was visually observed for each 10 times of bending, and the wire breakage inhibition of the wiring was evaluated by the number of times of bending in which cracks were generated. The results are shown in Table 2.
(evaluation of warp Property)
The curable resin composition was coated on a polyimide substrate (Kapton (registered trademark) 100EN, thickness 25 μm, manufactured by dol corporation, ori) by screen printing using a #180 mesh polyester printing plate.
The substrate coated with the curable resin composition thus obtained was placed in a hot air circulation dryer at a temperature of 80 ℃ for 30 minutes, and then placed in a hot air circulation dryer at a temperature of 120 ℃ for 60 minutes, thereby curing the coating film of the curable resin composition formed on the substrate.
The substrate having the cured film was cut using a circular cutter to obtain a circular substrate (hereinafter referred to as "substrate") having a diameter of 50mm having the cured film. The obtained substrate exhibits convex or concave warp deformation near the center.
After the substrate was left at 23℃for 1 hour, the substrate was left in a state of protruding downward on a flat plate. That is, the convex portion near the center of the warp substrate is placed downward on the flat plate so that the convex portion of the warp substrate meets the horizontal plane of the flat plate. Next, the distance between the portion farthest from the horizontal plane of the flat plate and the distance between the portion closest to the horizontal plane of the flat plate in the peripheral portion of the warp substrate are measured, and the average value thereof is obtained, and the warp is evaluated based on the average value. The results are shown in Table 2.
The sign of the numerical value shown in table 2 indicates the warp direction, and when the substrate is left standing in a state protruding downward, the film of the cured product is indicated by "+" when it is located on the upper side with respect to the polyimide substrate, and the film of the cured product is indicated by "-" when it is located on the lower side with respect to the polyimide substrate. And, the warp size is qualified when it is more than-3.0 mm and less than +3.0mm.
(evaluation of reliability of insulation over a long period)
A flexible wiring board was manufactured by etching a flexible copper clad laminate (manufactured by sumitomo metal mine co., ltd., grade name: speclex US, copper thickness: 8 μm, polyimide thickness: 38 μm) to obtain a substrate having a fine comb pattern shape (copper wiring width/copper wiring interval=15 μm/15 μm) as described in JPCA-ET01 of the standard of the general corporate japan electronic circuit industry (JPCA), and further subjecting the substrate having the fine comb pattern shape to a tin plating treatment.
Then, a curable resin composition is applied to the flexible wiring board by a screen printing method. The film thickness of the printed curable resin composition was 15 μm after drying the film of the curable resin composition on the polyimide surface.
The flexible wiring board thus obtained was placed in a hot air circulation type dryer at a temperature of 80 ℃ for 30 minutes, and then placed in a hot air circulation type dryer at a temperature of 120 ℃ for 120 minutes, thereby curing the film of the curable resin composition formed on the flexible wiring board.
Then, a bias voltage of 60V was applied to the test piece using MIGRATION TESTER MODELMIG-8600 manufactured by IMV, and a temperature and humidity routine test was performed on the test piece under conditions of a temperature of 120℃and a humidity of 85% RH.
The resistance values of the flexible wiring boards were measured at the beginning of the temperature and humidity routine test, 100 hours after the beginning, 250 hours and 400 hours after the beginning, respectively. The results are shown in Table 2.
(determination of spin-spin relaxation time T2 by pulse Nuclear magnetic resonance method)
The curable resin composition was applied to a release-treated PET film (grade name: lumirror, manufactured by Toli Co., ltd., thickness: 125 μm) by bar coating printing so that the thickness after curing was 30 μm and the width was 75mm and the length was 110 mm. After the PET film printed with the curable resin composition was kept at room temperature for 10 minutes, it was placed in a hot air circulation dryer at a temperature of 120 ℃ for 60 minutes, and then placed in a hot air circulation dryer at a temperature of 150 ℃ for 120 minutes, so that the film of the curable resin composition formed on the PET film was cured to form a cured film.
After peeling the PET film, the film of the cured product was cut into a long sample having a length of 3cm and a width of 5mm by a cutter. Then, the sample was placed in a glass sample tube having a diameter of 10mm so that the total mass was about 500mg, and the glass sample tube was mounted in a pulse nuclear magnetic resonance apparatus so that the sample was positioned at the coil portion of the pulse nuclear magnetic resonance apparatus. 3 samples were measured under the following conditions, and the free induction decay signal f (T) obtained by the measurement was curve-fitted (Mono-extexing), to calculate the spin-lattice relaxation time T1. The results are shown in Table 2.
Device Biospin the minispec mq by Bruker Co., ltd
Determination of the species of nuclei, hydrogen nuclei
Measuring temperature at 40 DEG C
Measuring frequency 20MHz
Pulse procedure T1 reverse recovery method (Inversion Recovery method)
Initial pulse interval (First Pulse Separation) of 5ms
Final pulse interval (Final Pulse Separation): 1000ms
Cycle delay (1 s)
Gain (Gain) 95dB
Data Points (Data Points): 20
Delay sampling window (Delay Sampling Window) of 0.050ms
Sampling Window (Sampling Window) 0.020ms
Scanning (Scan) 16 times
Acquisition Scale (Acquisition scale): 0.3ms
The calculated spin-lattice relaxation times T1 are all values far smaller than 1s, and if the cyclic delay (cycle delay) =t1×5s is set to 1s in the measurement of the spin-spin relaxation time, it can be said that the relaxation time is quite abundant. Therefore, the spin-spin relaxation time (T2) was measured by the pulse nuclear magnetic resonance method on 3 samples under the following conditions by setting the cycle delay (cycle delay) to 1s in substantially the same manner as in the case of the spin-lattice relaxation time T1.
Device Biospin the minispec mq by Bruker Co., ltd
Determination of the species of nuclei, hydrogen nuclei
Measuring frequency 20MHz
Measuring temperature at 40 DEG C
Pulse procedure T2 SOLID ECHO method (SOLID ECHO method)
Cycle delay (1 s)
Gain (Gain) 77dB
Data Points (Data Points): 100
Scanning (Scan) 16 times
Acquisition Scale (Acquisition scale): 0.3ms
The free induction Decay signal f (t) obtained by the above measurement was curve-fitted (7. Gauss-Decay Extended) using the above mathematical formula as a fitted calculation formula. At this time, the weibull coefficient is set to W (1) =2.0, W (2) =1.0, and W (3) =1.0. Further, curve fitting was performed for a range where the decay time t is within 0.3 ms.
A (1), A (2), T2 (1), T2 (2) and T2 (3) are obtained by curve fitting. From the obtained a (1), a (2), T2 (1), and T2 (2) [ a (1) ×t2 (1) +a (2) ×t2 (2) ]. The results are shown in Table 2.
As is clear from the results shown in table 2, the flexible wiring boards of examples 1 to 9, in which the value of [ a (1) ×t2 (1) +a2×t2 (2) ] was 0.015ms or less and T2 (3) was 0.50ms or more, were excellent in low warpage, flexibility, wire breakage inhibition, and long-term insulation reliability.
Therefore, films containing cured products of the curable resin compositions F1 to F9 can be used as insulating protective films for flexible wiring boards. In particular, since the flexible wiring board having the overcoat film containing the cured product of the curable resin compositions F1 to F9 is excellent in low warpage, the workability in the printing step and the curing step is improved. For example, in a packaging process for mounting an IC chip on a flexible wiring board, positioning accuracy of a mounting position of the IC chip is improved, thereby improving yield of a manufacturing process.
In contrast, the flexible wiring boards of comparative examples 1 and 2 in which [ a (1) ×t2 (1) +a2) ×t2 (2) ] had a value exceeding 0.015ms and T2 (3) was less than 0.50ms were poor in low warpage and wire breakage inhibition.

Claims (16)

1. A cured product of a curable resin composition, wherein,
a free induction decay signal f (T) for determining the magnetization of a spin-spin relaxation time T2 of a proton is measured at a measurement frequency of 20MHz by a pulse nuclear magnetic resonance method, and when the free induction decay signal f (T) is approximated by the following mathematical expression, the value of [ A (1) ×T2 (1) +A2) ×T2 (2) ] calculated from A (1), A (2), T2 (1) and T2 (2) in the mathematical expression is 0.015ms or less, and T2 (3) is 0.50ms or more;
[ mathematics 1]
Wherein (offset) of item 4 of the above formula consisting of 4 items is an offset item; a (1), a (2), and a (3) in the above formulas are constants, respectively, and a (1) +a (2) +a (3) =1; t2 (1), T2 (2) and T2 (3) in the above formula are spin-spin relaxation times T2, respectively, and T2 (1) < T2 (2) < T2 (3); w (1), W (2) and W (3) in the above formula are each Weibull coefficients and are numbers of 1 to 2 inclusive; in the above formula, t is time, exp is an exponential function based on a Napi constant e,
The curable resin composition contains:
a polyurethane (a) having a functional group reactive with an epoxy group;
a solvent (b); and
1 an epoxy compound (c) having 2 or more epoxy groups in the molecule,
the polyurethane (a) has trans 1, 4-cyclohexanedimethylene groups.
2. The cured product according to claim 1, wherein,
the polyurethane (a) has at least one of a first urethane structural unit and a second urethane structural unit; wherein the first urethane structural unit has at least one of a polyester structure and a polycarbonate structure; the second urethane structural unit has a carboxyl group.
3. The cured product according to claim 2, wherein,
the polyurethane (a) has a third urethane structural unit, wherein the third urethane structural unit has a fluorene structure.
4. The cured product according to claim 1 to 3, wherein,
the polyurethane (a) has a number average molecular weight of 10000 to 50000.
5. The cured product according to claim 1, wherein,
the acid value of the polyurethane (a) is 10-70 mgKOH/g.
6. The cured product according to claim 1, wherein,
the aromatic ring concentration of the polyurethane (a) is 0.1-5.0 mmol/g.
7. The cured product according to claim 1, wherein,
the content ratio of the solvent (b) is 25 mass% or more and 75 mass% or less with respect to the total amount of the curable resin composition;
the content ratio of the polyurethane (a) is 40 to 99 mass% with respect to the total amount of the polyurethane (a) and the epoxy compound (c).
8. The cured product according to claim 1, wherein,
the curable resin composition contains at least one fine particle (d) selected from the group consisting of inorganic fine particles and organic fine particles.
9. The cured product according to claim 8, wherein,
the particles (d) comprise silica particles.
10. The cured product according to claim 8, wherein,
the particles (d) comprise hydrotalcite particles.
11. The cured product according to claim 8, wherein,
the content ratio of the solvent (b) is 25 mass% or more and 75 mass% or less with respect to the total amount of the curable resin composition;
the content ratio of the fine particles (d) is 0.1 mass% or more and 60 mass% or less with respect to the total amount of the polyurethane (a), the solvent (b), the epoxy compound (c) and the fine particles (d);
The content ratio of the polyurethane (a) is 40 to 99 mass% with respect to the total amount of the polyurethane (a) and the epoxy compound (c).
12. A method for producing a cured product according to any one of claims 1 to 11, wherein,
which cures the curable resin composition by heat or active energy rays.
13. An exterior coating film, wherein,
a cured product according to any one of claims 1 to 11.
14. A flexible wiring board, wherein,
a portion of the surface of the flexible substrate on which the wiring is formed of the flexible wiring board, the portion on which the wiring is formed being covered with the overcoat film of claim 13.
15. The flexible wiring board as claimed in claim 14, wherein,
the wiring is a tinned copper wire.
16. A method for measuring a cured product of a curable resin composition, wherein,
a free induction decay signal f (T) for determining the magnetization of a spin-spin relaxation time T2 of a proton is measured at a measurement frequency of 20MHz by a pulse nuclear magnetic resonance method, and when the free induction decay signal f (T) is approximated by the following mathematical expression, the value of [ A (1) ×T2 (1) +A2) ×T2 (2) ] calculated from A (1), A (2), T2 (1) and T2 (2) in the mathematical expression is 0.015ms or less, and T2 (3) is 0.50ms or more;
[ mathematics 1]
Wherein (offset) of item 4 of the above formula consisting of 4 items is an offset item; a (1), a (2), and a (3) in the above formulas are constants, respectively, and a (1) +a (2) +a (3) =1; t2 (1), T2 (2) and T2 (3) in the above formula are spin-spin relaxation times T2, respectively, and T2 (1) < T2 (2) < T2 (3); w (1), W (2) and W (3) in the above formula are each Weibull coefficients and are numbers of 1 to 2 inclusive; in the above formula, t is time, exp is an exponential function based on a naphal constant e.
CN202080049525.8A 2019-07-08 2020-05-29 Cured product, overcoat film, and flexible wiring board Active CN114080408B (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP2019-126908 2019-07-08
JP2019126908 2019-07-08
PCT/JP2020/021412 WO2021005914A1 (en) 2019-07-08 2020-05-29 Cured object, overcoat film, and flexible wiring board

Publications (2)

Publication Number Publication Date
CN114080408A CN114080408A (en) 2022-02-22
CN114080408B true CN114080408B (en) 2023-08-25

Family

ID=74114513

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202080049525.8A Active CN114080408B (en) 2019-07-08 2020-05-29 Cured product, overcoat film, and flexible wiring board

Country Status (5)

Country Link
JP (1) JPWO2021005914A1 (en)
KR (1) KR20220032573A (en)
CN (1) CN114080408B (en)
TW (1) TWI800737B (en)
WO (1) WO2021005914A1 (en)

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102559087A (en) * 2010-11-30 2012-07-11 日东电工株式会社 Surface protective sheet
CN103563056A (en) * 2011-04-15 2014-02-05 富士纺控股株式会社 Polishing pad and manufacturing method therefor
CN105229536A (en) * 2013-05-14 2016-01-06 株式会社理光 Toner, developer, image forming apparatus and image forming method
WO2016017797A1 (en) * 2014-08-01 2016-02-04 積水化学工業株式会社 Flame-retardant polyurethane resin composition
CN108368336A (en) * 2015-12-25 2018-08-03 昭和电工株式会社 Solidification compound, solidfied material, outer film, covering flexible wiring sheet and its manufacturing method
CN108473653A (en) * 2015-12-25 2018-08-31 昭和电工株式会社 New polyurethane, solidification compound, outer film and flexible wiring sheet and its manufacturing method
CN109232844A (en) * 2017-07-10 2019-01-18 日本发条株式会社 Padded coaming, seat padded coaming and seat
JP6498265B1 (en) * 2017-12-15 2019-04-10 日本発條株式会社 Seat cushion and seat
JP2021012123A (en) * 2019-07-08 2021-02-04 昭和電工株式会社 Cured product characteristic value estimation method

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP6735751B2 (en) 2014-12-15 2020-08-05 エモリー ユニバーシティー Phosphoramidate for the treatment of hepatitis B virus

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102559087A (en) * 2010-11-30 2012-07-11 日东电工株式会社 Surface protective sheet
CN103563056A (en) * 2011-04-15 2014-02-05 富士纺控股株式会社 Polishing pad and manufacturing method therefor
CN105229536A (en) * 2013-05-14 2016-01-06 株式会社理光 Toner, developer, image forming apparatus and image forming method
WO2016017797A1 (en) * 2014-08-01 2016-02-04 積水化学工業株式会社 Flame-retardant polyurethane resin composition
JPWO2016017797A1 (en) * 2014-08-01 2017-05-18 積水化学工業株式会社 Flame retardant polyurethane resin composition
CN108368336A (en) * 2015-12-25 2018-08-03 昭和电工株式会社 Solidification compound, solidfied material, outer film, covering flexible wiring sheet and its manufacturing method
CN108473653A (en) * 2015-12-25 2018-08-31 昭和电工株式会社 New polyurethane, solidification compound, outer film and flexible wiring sheet and its manufacturing method
CN109232844A (en) * 2017-07-10 2019-01-18 日本发条株式会社 Padded coaming, seat padded coaming and seat
JP6498265B1 (en) * 2017-12-15 2019-04-10 日本発條株式会社 Seat cushion and seat
JP2021012123A (en) * 2019-07-08 2021-02-04 昭和電工株式会社 Cured product characteristic value estimation method

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
利用LF-NMR研究燃速催化剂对推进剂固化反应的影响;贾林等;《固体火箭技术》;20151015(第05期);第697-703页 *

Also Published As

Publication number Publication date
KR20220032573A (en) 2022-03-15
CN114080408A (en) 2022-02-22
WO2021005914A1 (en) 2021-01-14
TWI800737B (en) 2023-05-01
JPWO2021005914A1 (en) 2021-01-14
TW202106741A (en) 2021-02-16

Similar Documents

Publication Publication Date Title
CN108368336B (en) Curable composition, cured product, overcoat film, covered flexible wiring board, and method for producing same
EP2390277B1 (en) (poly)carbonate polyol and carboxyl group-containing polyurethane using the (poly)carbonate polyol as starting material
CN108473653B (en) Polyurethane, curable composition, overcoat film, flexible wiring board, and method for producing same
CN109071954B (en) Curable composition, cured film using same, and overcoat film
KR101503987B1 (en) Thermosetting composition
EP2390276B1 (en) Carboxyl group-containing polyurethane
CN114080408B (en) Cured product, overcoat film, and flexible wiring board
JP2021012123A (en) Cured product characteristic value estimation method
CN114072444B (en) Curable composition, cured product, overcoat film, flexible wiring board, and method for producing same
CN114096579B (en) Polyurethane and curable composition
CN109071955B (en) Curable composition, cured film using same, and overcoat film
TWI753456B (en) Curable composition, cured object, overcoat film and flexible wiring board and a method of manufacturing thereof
WO2020246154A1 (en) Method of producing polyurethane and method of producing overcoat film for flexible wiring board
WO2020246221A1 (en) Method of producing polyurethane and method of producing overcoat film for flexible wiring board
WO2020137347A1 (en) Method for producing polyurethane, method for producing curable composition, method for producing cured product, method for producing overcoat film and method for producing flexible wiring board
JP2021011545A (en) Polyurethane and curable composition
JP2021095478A (en) Polyurethane and curable composition

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant