阅读说明：本技术 聚碳酸酯树脂和含有其的光学构件 (Polycarbonate resin and optical member containing same ) 是由 大山达也 小笠原一良 梅木笃志 佐藤敬介 松井学 于 2019-03-20 设计创作，主要内容包括：本发明的目的在于提供不使用双酚A作为原料且高温耐湿性高的聚碳酸酯树脂。本发明涉及一种聚碳酸酯树脂,其含有式(1)、式(2)和式(3)的重复单元,下述式(3)的重复单元为5mol％～50mol％,且该聚碳酸酯树脂的折射率为1.570～1.600{式(1)中,R<Sub>1</Sub>和R<Sub>2</Sub>分别表示氢原子或碳原子数1～10的烃基}{式(3)中,n为0～8的范围,R分别从碳原子数1～3的烷基中选择}。<Image he="778" wi="700" file="DDA0002522014730000011.GIF" imgContent="drawing" imgFormat="GIF" orientation="portrait" inline="no"></Image>(The purpose of the present invention is to provide a polycarbonate resin which does not use bisphenol A as a raw material and has high-temperature moisture resistance. The present invention relates to a polycarbonate resin comprising repeating units of formulae (1), (2) and (3), wherein the repeating unit of formula (3) is 5 to 50 mol%, and the refractive index of the polycarbonate resin is 1.570 to 1.600{ formula (1) }, R 1 And R 2 Each represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms { in formula (3), n is in the range of 0 to 8, and R is selected from alkyl groups having 1 to 3 carbon atoms }.)

1. A polycarbonate resin comprising repeating units of formulae (1), (2) and (3), wherein the repeating unit of formula (3) is 5 to 50 mol%, and the refractive index of the polycarbonate resin is 1.570 to 1.600,

in the formula (1), R₁And R₂Each represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms,

in the formula (3), n is in the range of 0-8, and R is selected from alkyl with 1-3 carbon atoms.

2. The polycarbonate resin according to claim 1, wherein the repeating unit of formula (3) is 10 to 40 mol%.

3. The polycarbonate resin according to claim 1 or 2, wherein the repeating unit of formula (1) is 20 to 70 mol%.

4. The polycarbonate resin according to any one of claims 1 to 3, wherein the repeating unit of formula (2) is 10 to 60 mol%.

5. The polycarbonate resin of claim 1 or 2, wherein R₁And R₂Are all hydrogen and are in the form of hydrogen,

the repeating unit of the formula (1) is 40 mol% to 65 mol%, and

the repeating unit of the formula (2) is 10 mol% to 35 mol%.

6. The polycarbonate resin of claim 1 or 2, wherein R₁And R₂Are all phenyl groups, and the phenyl groups,

the repeating unit of the formula (1) is 25 mol% to 50 mol%, and

the repeating unit of the formula (2) is 15 mol% to 60 mol%.

7. The polycarbonate resin according to any one of claims 1 to 6, wherein the ratio of terminal phenolic hydroxyl groups to the total polymer terminals is 15% or less.

8. The polycarbonate resin of any of claims 1-7, wherein the recurring units of formula (3) are introduced by bisphenol TMC.

9. The polycarbonate resin according to any one of claims 1 to 8, wherein the Abbe number is from 26.0 to 31.0.

10. The polycarbonate resin of any one of claims 1-9, wherein the oriented birefringence is 5 × 10^-3The following.

11. An optical member comprising the polycarbonate resin according to any one of claims 1 to 10.

12. The optical member according to claim 11, which is a lens.

13. The optical member according to claim 11, which is a phase difference film.

14. The optical member according to claim 12, which is a photographic lens for any one of a mobile phone, a smartphone, a tablet terminal, a personal computer, a digital camera, a video camera, an in-vehicle camera, or a surveillance camera.

Technical Field

The present invention relates to a polycarbonate and an optical member containing the same, and particularly relates to an imaging lens.

Background

There is a strong demand for improvement in low birefringence and aberration correction capability of plastic imaging lenses used in devices such as smartphones. Conventionally, such an imaging lens performs aberration correction by a combination of a plurality of lenses having different optical characteristics (refractive index and abbe number) and a combination of lens shapes.

Among transparent resins for optical use which have been put to practical use in lens applications, polycarbonate resins (nd ═ 1.584) using bisphenol a as a raw material have been widely used as resins having a high refractive index and a low abbe number. However, polycarbonate resins made from bisphenol a have a weak point of large birefringence, and therefore cannot be used for recent high-resolution cameras.

In contrast, patent document 1 discloses an imaging lens made of a polycarbonate resin having a small birefringence without using bisphenol a as a raw material.

Disclosure of Invention

The imaging lens described in patent document 1 is very useful because of its low birefringence and water absorption, but it is known that there is a problem in moisture resistance at high temperatures. Accordingly, an object of the present invention is to provide a polycarbonate resin which does not use bisphenol a as a raw material and has high temperature and high moisture resistance, and an optical member containing the same.

The present inventors have found that the above problems can be solved by the present invention having the following modes.

Mode 1

A polycarbonate resin comprising repeating units of formulae (1), (2) and (3), wherein the repeating unit of formula (3) is 5 to 50 mol%, and the refractive index of the polycarbonate resin is 1.570 to 1.600,

{ formula (1) { wherein R₁And R₂Each represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms }

{ formula (3), n is 0-8, R is selected from C1-3 alkyl }.

Mode 2

The polycarbonate resin according to embodiment 1, wherein the repeating unit of the formula (3) is 10 to 40 mol%.

Mode 3

The polycarbonate resin according to embodiment 1 or 2, wherein the repeating unit of formula (1) is 20 to 70 mol%.

Mode 4

The polycarbonate resin according to any one of embodiments 1 to 3, wherein the repeating unit of the formula (2) is 10 to 60 mol%.

Mode 5

The polycarbonate resin according to mode 1 or 2, wherein R₁And R₂Are all hydrogen and are in the form of hydrogen,

the repeating unit of the formula (1) is 40 to 65 mol%, and

the repeating unit of the formula (2) is 10 to 35 mol%.

Mode 6

The polycarbonate resin according to mode 1 or 2, wherein，R₁And R₂Are all phenyl groups, and the phenyl groups,

the repeating unit of the formula (1) is 25 to 50 mol%, and

the repeating unit of the formula (2) is 15 to 60 mol%.

Mode 7

The polycarbonate resin according to any one of embodiments 1 to 6, wherein a ratio of terminal phenolic hydroxyl groups to all polymer terminals is 15% or less.

Mode 8

The polycarbonate resin according to any one of embodiments 1 to 7, wherein the repeating unit of formula (3) is introduced from bisphenol TMC.

Mode 9

The polycarbonate resin according to any one of embodiments 1 to 8, wherein an Abbe number is 26.0 to 31.0.

According to mode 10

The polycarbonate resin according to any one of embodiments 1 to 9, wherein the oriented birefringence is 5 × 10^-3The following.

According to mode 11

An optical member comprising the polycarbonate resin according to any one of modes 1 to 10.

According to mode 12

The optical member according to mode 11, which is a lens.

According to mode 13

The optical member according to mode 11, which is a retardation film.

According to mode 14

The optical member according to mode 12, which is an imaging lens used for any one of a mobile phone, a smartphone, a tablet terminal, a personal computer, a digital camera, a video camera, an in-vehicle camera, or a surveillance camera.

Detailed Description

Polycarbonate resin

The polycarbonate resin of the present invention contains a fluorene-based unit of the formula (1), an oxaspiro undecane-based unit of the formula (2), and a cyclohexylidene bisphenol-based unit of the formula (3), and the repeating unit of the formula (3) is 5 to 50 mol%. The resin of the present invention has a refractive index of 1.570 to 1.600.

The imaging lens described in patent document 1 is very useful because of its low birefringence and water absorption rate, and has a certain heat resistance, but the present inventors have found that the imaging lens described in patent document 1 is whitened by being exposed to high temperature and high humidity for a long time.

The present inventors have also found that whitening of the imaging lens described in patent document 1 can be substantially prevented by introducing a certain degree of the repeating unit of formula (3) into the resin described in patent document 1.

In the case of the repeating unit of the above formula (3), it is known from the resin described in patent document 1 that the high-temperature moisture resistance is improved, the refractive index and the abbe number are not substantially changed, the birefringence and the water absorption rate are not practically problematic, and the molding into a lens is easy. In the polycarbonate resin for optical use, it is very difficult to improve other properties without substantially changing the refractive index and abbe number and without practically causing any problem in birefringence and water absorption while changing the monomer composition, and it is unexpected to obtain the above-mentioned properties by introducing the repeating unit of the above formula (3).

Although not being bound by theory, the reason why the above-mentioned results are obtained by introducing the repeating unit of the above-mentioned formula (3) is that 2 benzene rings and a cyclohexylene group located therebetween are present in the repeating unit of the above-mentioned formula (3). Since the carbon bonded to 2 benzene rings is a quaternary carbon atom, 3 cyclic structures do not exist on the same plane. Accordingly, the polycarbonate resin of the present invention is considered to have a small birefringence and to have an improved heat resistance because the movement of the main chain of the polymer is restricted. Particularly, if a substituent R is present in the cyclohexylene group in the repeating unit of the above formula (3), the movement of the main chain of the polymer is further conspicuous, and thus it is preferable.

Polymeric structure

The polycarbonate resin of the present invention contains a repeating unit of the above formula (1). As described aboveR in the formula (1)₁And R₂Each represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, and examples of the hydrocarbon group include an alkyl group, a cycloalkyl group and an aryl group, and particularly include a phenyl group. Preferably R₁And R₂Respectively hydrogen atom or phenyl.

The polycarbonate resin of the present invention may contain 20 mol% or more, 25 mol% or more, 30 mol% or more, 40 mol% or more, 45 mol% or more, 50 mol% or more, 55 mol% or more, or 60 mol% or more of the repeating unit of the above formula (1), and may contain 70 mol% or less, 65 mol% or less, 60 mol% or less, 55 mol% or less, 50 mol% or less, 45 mol% or less, 40 mol% or less, or 35 mol% or less of the repeating unit of the above formula (1). For example, the resin of the present invention may contain the repeating unit of the above formula (1) in an amount of 20 to 70 mol% or 40 to 60 mol%.

R₁And R₂In the case where all are small groups (for example, hydrogen atoms), it is preferable that the polycarbonate resin of the present invention contains the repeating unit of the above formula (1) in an amount of 40 to 65 mol% or 45 to 55 mol%. R₁And R₂When the number of groups is large (for example, phenyl groups), it is preferable that the polycarbonate resin of the present invention contains the repeating unit of the above formula (1) in an amount of 25 to 50 mol% or 30 to 40 mol%.

The polycarbonate resin of the present invention may contain 10 mol% or more, 15 mol% or more, 20 mol% or more, 25 mol% or more, 30 mol% or more, 35 mol% or more, 40 mol% or more, or 45 mol% or more of the repeating unit of the above formula (2), and may contain 60 mol% or less, 55 mol% or less, 50 mol% or less, 45 mol% or less, 40 mol% or less, 35 mol% or less, 30 mol% or less, 25 mol% or less, or 20 mol% or less of the repeating unit of the above formula (2). For example, the resin of the present invention may contain the repeating unit of the above formula (2) in an amount of 10 to 60 mol% or 10 to 35 mol%.

Containing R₁And R₂In the case of the repeating unit of the above formula (1) in which all the groups are small (for example, hydrogen atoms), it is preferable that the polycarbonate resin of the present invention contains the repeating unit of the above formula (2) in an amount of 10 to 35 mol% or 20 to 30 mol%. Containing R₁And R₂Formula (1) above wherein each is a larger group (e.g., phenyl)) In the case of the repeating unit(s) of (3), the polycarbonate resin of the present invention preferably contains the repeating unit of the formula (2) in an amount of 15 to 60 mol%, 20 to 50 mol% or 30 to 45 mol%.

The polycarbonate resin of the present invention may contain 5 mol% or more, 10 mol% or more, 15 mol% or more, 20 mol% or more, 25 mol% or more, or 30 mol% or more of the repeating unit of the above formula (3), and may contain 60 mol% or less, 55 mol% or less, 50 mol% or less, 40 mol% or less, 35 mol% or less, 30 mol% or less, 25 mol% or less, 20 mol% or less, or 15 mol% or less of the repeating unit of the above formula (3). The polycarbonate resin of the present invention preferably contains 10 to 40 mol% or 15 to 25 mol% of the repeating unit of the formula (3).

Containing R₁And R₂In the case of the repeating unit of the above formula (1) in which all the groups are small (for example, hydrogen atoms), it is preferable that the polycarbonate resin of the present invention contains the repeating unit of the above formula (3) in an amount of 5 to 50 mol% or 15 to 35 mol%. Containing R₁And R₂In the case of the repeating units of the formula (1) each having a relatively large group (e.g., phenyl group), it is preferable that the polycarbonate resin of the present invention contains 15 to 55 mol%, 20 to 50 mol%, or 25 to 40 mol% of the repeating units of the formula (3).

In the formula (3), n is in the range of 0 to 8, preferably 0 to 5 or 1 to 3, and particularly preferably 3. R is selected from alkyl groups having 1 to 3 carbon atoms, and is preferably a methyl group or an ethyl group, and particularly preferably a methyl group. In addition, it is particularly preferable that the repeating unit of the above formula (3) is 4,4 ' - (3,3, 5-trimethylcyclohexylidene) bisphenol (so-called bisphenol TMC), 4 ' -cyclohexylidene bisphenol (so-called bisphenol Z), or 4,4 ' - (3-methylcyclohexylidene) bisphenol (so-called bisphenol MZ), and among these, bisphenol TMC is more preferable.

The polycarbonate resin of the present invention may contain a repeating unit other than the repeating units of the above formula (1), the above formula (2) and the above formula (3) within a range in which the advantageous effects of the present invention are obtained. As dihydroxy compounds which provide such repeating units, there may be mentioned ethylene glycol, propylene glycol, butylene glycol, pentylene glycol, hexylene glycol, heptylene glycol, octylene glycol, nonylene glycol, tricyclo [5.2.1.0 ] diol^2,6]Decane dimethanol, cyclohexane-1, 4-dimethanol, decalin2, 6-dimethanol, norbornandimethanol, pentacyclopentadecane dimethanol, cyclopentane-1, 3-dimethanol, isosorbide, isomannide, isoidide, hydroquinone, resorcinol, 2-bis (4-hydroxyphenyl) propane, 2-bis (3-methyl-4-hydroxyphenyl) propane, 1-bis (4-hydroxyphenyl) -1-phenylethane, bis (4-hydroxyphenyl) diphenylmethane, 1, 3-bis (2- (4-hydroxyphenyl) -2-propyl) benzene, bis (4-hydroxyphenyl) sulfone, bis (4-hydroxyphenyl) sulfide, biphenol, bisphenol fluorene, biscresol fluorene, etc. Such a repeating unit may be 10 mol% or less in the whole repeating unit.

The polycarbonate resin of the present invention preferably has no phenolic hydroxyl group at the polymer terminal. That is, if a monomer having a repeating unit represented by the above formula (3) is polymerized and bonded to the end of the polymer, the end group becomes a phenolic hydroxyl group. Therefore, it is preferable to reduce the amount of the terminal phenolic hydroxyl group of the polymer by using the carbonic acid diester in an excess amount to, for example, the dihydroxy compound as a raw material in polymerization to make the terminal phenyl group.

The ratio of the terminal phenolic hydroxyl groups can be determined as follows.

Terminal phenolic hydroxyl group ratio (amount of terminal phenolic hydroxyl group/amount of total polymer terminals) × 100

All polymer terminals are composed of a terminal phenolic hydroxyl group, a terminal alcoholic hydroxyl group, and a terminal phenyl group.

Although not limited to this example, the terminal phenolic hydroxyl group ratio can be specifically determined by the following method.

(1) By means of polymers¹The terminal phenolic hydroxyl group was observed by H NMR measurement, and the peak was integrated and set to 1. At this time, the integrated intensity (a) of 1 proton part was determined from the integrated intensities of the peaks at the 4-and 5-positions derived from the fluorene structure of the above formula (1).

Of course, when no peak of the terminal phenolic hydroxyl group is observed, the terminal phenolic hydroxyl group ratio is 0.

(2) The average polymerization degree of the polymer was determined from the number average molecular weight obtained by GPC measurement of the polymer, the molecular weight of each repeating unit and the molar ratio, and the polymer powder was determined from the mol% and the integrated intensity (A) of the above formula (1) by the following formulaOf the terminal¹Integrated intensity in H NMR spectrum (B).

(B) (A) × 100 × 2/([ mol% of the above formula (1) ] × average polymerization degree)

(3) The ratio of the terminal phenolic hydroxyl groups was determined as 1/(B) × 100.

The ratio of the terminal phenolic hydroxyl groups is preferably 30% or less, 20% or less, 15% or less, 10% or less, 5% or less, 3% or less, 1% or less, or 0.5% or less with respect to the total polymer terminals of the polycarbonate resin of the present invention.

Examples of the carbonic acid diester used for capping the terminal phenolic hydroxyl group include carbonic acid diesters such as an aryl group having 6 to 12 carbon atoms and an aralkyl group which may be substituted. Specific examples thereof include diphenyl carbonate, ditolyl carbonate, bis (chlorophenyl) carbonate and bis (m-tolyl) carbonate. Among them, diphenyl carbonate is particularly preferable. The amount of the carbonic acid diester to be used is preferably 0.95 to 1.10mol, more preferably 0.98 to 1.04mol, based on 1mol of the total of the dihydroxy compounds for providing the repeating units of the formulae (1) to (3).

Properties of Polymer

The polycarbonate resin of the present invention may have physical properties similar to those of the polycarbonate resin described in patent document 1, except for physical properties related to high-temperature moisture resistance.

Accordingly, the refractive index of the polycarbonate resin of the present invention is measured at a temperature: 25 ℃ and wavelength: when measured at 589nm, the value is desirably 1.570 or more, and may be 1.575 or more, 1.580 or more, 1.585 or more, or 1.590 or more, and may be 1.600 or less, or 1.595 or less, or 1.590 or less.

The abbe number of the polycarbonate resin of the present invention may be 26.0 or more, 26.5 or more, 27.0 or more, 27.5 or more, or 28.0 or more, and may be 30.0 or less, 29.0 or less, 28.5 or less, 28.0 or less, or 27.5 or less.

Here, abbe number is represented by temperature: 25 ℃ and wavelength: refractive indices at 486.13nm, 587.56nm, 656.27nm were calculated using the following formula:

νd＝(nd－1)/(nF－nC)

nd refers to the refractive index at a wavelength of 587.56nm,

nF refers to the refractive index at a wavelength of 486.13nm,

nC refers to the refractive index at a wavelength of 656.27 nm.

The specific viscosity of the polycarbonate resin of the present invention is preferably in the range of 0.12 to 0.32, and more preferably in the range of 0.18 to 0.30. When the specific viscosity is 0.12 to 0.32, the balance between moldability and strength is excellent.

The specific viscosity was measured by measuring the specific viscosity (η) at 20 ℃ of a solution prepared by dissolving 0.7g of a polycarbonate resin in 100ml of methylene chloride with an Ostwald viscometer_SP) The calculation is performed by the following equation.

Specific viscosity (η)_SP)＝(t－t₀)/t₀

[t₀The number of seconds of methylene chloride falling, and t is the number of seconds of sample solution falling]

The absolute value of the orientation birefringence (. DELTA.n) of the polycarbonate resin of the present invention is preferably 5.0 × 10^-34.0 × 10 below^-32.0 × 10 below^-3The following. The oriented birefringence (. DELTA.n) was measured at a wavelength of 589nm after stretching a cast film having a thickness of 100 μm obtained from the polycarbonate resin 2 times at Tg +10 ℃.

The polycarbonate resin of the present invention has a total light transmittance of preferably 80% or more, more preferably 85% or more, and further preferably 88% or more, at a thickness of 1 mm.

The water absorption of the polycarbonate resin of the present invention after immersion at 23 ℃ for 24 hours is preferably 0.20% or less, more preferably 0.18% or less.

The glass transition temperature of the polycarbonate resin of the present invention may be 120 ℃ or higher, 125 ℃ or higher, 130 ℃ or higher, 135 ℃ or higher, 140 ℃ or higher, 145 ℃ or higher, or 150 ℃ or higher, and may be 160 ℃ or lower, 155 ℃ or lower, 150 ℃ or lower, 145 ℃ or lower, 140 ℃ or lower, or 135 ℃ or lower.

The polycarbonate resin of the present invention preferably has a heat humidity of 2000h Δ b of 10 or less, more preferably 5 or less, and still more preferably 3 or less.

The Δ b value of the polycarbonate resin of the present invention before and after PCT treatment is preferably 3 or less, more preferably 2 or less, and still more preferably 1 or less.

Manufacturing method

The polycarbonate resin of the present invention can be produced by a reaction method known per se for producing a usual polycarbonate resin, for example, a method of reacting a carbonate precursor such as a carbonic acid diester with a dihydroxy compound. In this production method, patent document 1 can be referred to, except that a monomer for providing the repeating unit of formula (3) is used.

Optical component

The optical member of the present invention contains the above polycarbonate resin. Such an optical member is not particularly limited as long as it is useful for the optical use of the polycarbonate resin, and examples thereof include an optical disk, a transparent conductive substrate, an optical card, a sheet, a film, an optical fiber, a lens, a prism, an optical film, a substrate, an optical filter, and a hard coat film.

The optical member of the present invention may be composed of a resin composition containing the above-mentioned polycarbonate resin, and additives such as a heat stabilizer, a plasticizer, a light stabilizer, a polymeric metal deactivator, a flame retardant, a lubricant, an antistatic agent, a surfactant, an antibacterial agent, an ultraviolet absorber, and a mold release agent may be added to the resin composition as needed.

Camera lens

The optical member of the present invention is particularly an imaging lens. Examples of such an imaging lens include imaging lenses used in mobile phones, smart phones, tablet terminals, personal computers, digital cameras, video cameras, in-vehicle cameras, surveillance cameras, and the like. As a method for molding such an imaging lens, patent document 1 can be referred to.

The present invention will be further specifically described with reference to the following examples, but the present invention is not limited thereto.