JPH08220407A - Optical pickup lens holder - Google Patents

Abstract

PURPOSE: To obtain a resin with which an optical pickup lens holder is formable with good accuracy by composing this resin of a compsn. consisting essentially of a specific liquid crystalline resin and inorg. filler and providing this resin with specific fire-retardant performance. CONSTITUTION: This optical pickup lens holder consists of the compsn. essentially consisting of the liquid crystalline resin (A) of which the m.p. width obtd. by a differential scanning calorimeter is <=30 deg.C and the inorg. fillers (B) and has the fire-retardant performance of UL-94V-O at a thickness of 1/64 inch. A lens 2 is held by the lens holder l. The m.p. (Tm) refers to the peak of an endothermic peak temp. (Tm2 ) observed in the following manner: A polymer with which the polymn. is completed is measured under a heating up condition of 40 deg.C/min from room temp. in differential heat quantity measurement and its endothermic peak temp. (Tm1 ) is observed. The polymer is then held for five minutes at a temp. of Tm1 +20 deg.C after this observation and thereafter, the polymer is once cooled down to room temp. under a temp. lowering condition of 20 deg.C/min. The measurement is then made again under the heating up condition of 20 deg.C/min and the peak of Tm2 is observed at this time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical pickup lens holder used for compact discs, laser discs, video discs, magneto-optical discs and the like.

[0002]

2. Description of the Related Art An optical pickup is a compact disc,
It is used for laser discs, video discs, magneto-optical discs, etc., and is a pickup unit for an optical disc, which is equivalent to a pickup unit including a needle of a conventional audio record. The function of the optical pickup is to irradiate a semiconductor laser with a lens to a spot of a few μm diameter.
It reads the information recorded on the disc,
Since a lens holder for holding this lens has an extremely complicated shape and requires strict dimensional accuracy, a metal precision cut product has been conventionally used.

Metal cutting products are suitable for precision parts because they can produce precision and strength and have little dimensional change due to the environment. However, the manufacturing process is complicated and requires a lot of man-hours and is heavy. However, there are drawbacks such as susceptibility to rust, and attempts have been made to make this a resin. However, ordinary plastics have a problem in so-called melt fluidity, which depends on the viscosity at the time of melting, and also have difficulty in dimensional stability of products after molding, strength of thin products, etc., and simply change the material. I couldn't do that.

For example, Japanese Unexamined Patent Publication (Kokai) No. 62-236143 proposes that the optical system mounting block of the optical pickup is made of liquid crystalline polyester. This mounting block is a housing for holding the entire optical pickup. It does not require a finer structure and precision than a lens holder.

[0005]

The optical pickup lens holder is required to have an extremely fine structure and precision, and in particular, it is necessary that the thickness of the details is 0.5 μm or less. In order to mold such a thin molded product by injection molding, it is needless to say that ordinary plastics cannot be used, and only a specific liquid crystalline resin can be used. Because the thickness of the molded product is too thin, the molten resin does not flow into the end of the mold when molding with a normal resin. If a high pressure is applied to force this to flow, the resin will squeeze out between the molds, forming a so-called burr.

In view of the above situation, the present invention has been obtained as a result of studying a resin capable of accurately molding an optical pickup lens holder.

[0007]

Means for Solving the Problems That is, the present invention comprises a composition containing a liquid crystalline resin (A) and an inorganic filler (B) as the main components, the melting point width of which is 30 ° C. or less determined by a differential scanning calorimeter. UL-94 VO with a thickness of 1/64 inch
The present invention relates to an optical pickup lens holder having flame retardancy.

FIGS. 1 and 2 show views of a typical optical pickup lens holder of the present invention. FIG. 1 is a schematic plan view of a lens holder, FIG. 2 is a schematic side view, and 1 is a lens holder and 2 is a lens. FIG. 3 is a schematic sectional view of an optical pickup incorporating a lens holder, and the lens 2 is held by the lens holder 1. Also,
The other lens 2'is also held by the lens holder 1 '. In the figure, 3 is a reflecting member, 4 is a light emitting element, 5 is a diffraction grating, and 6 is a light receiving element.

The liquid crystalline resin of the present invention must have a melting point width of 30 ° C. or less from the viewpoint of homogeneity of the polymer.
Here, the melting point (Tm) is Tm after the observation of the endothermic peak temperature (Tm ₁ ) observed when measuring the polymer of which polymerization is completed at room temperature to 40 ° C./min in the differential calorimetry. Hold at a temperature of ₁ + 20 ° C for 5 minutes, then 20 ° C
After cooling once to room temperature under the temperature lowering condition of 1 / min, the temperature is 20 ℃ again.
The peak of the endothermic peak temperature (Tm ₂ ) observed when measured under the temperature rising condition of 1 / min.

In addition, | Tm ₁ − between Tm ₁ and Tm ₂
Tm ₂ | ≦ 10 ° C. is preferable, and | Tm ₁
-Tm ₂ | ≦ 6 ° C. is more preferable. This temperature difference is 10 ℃
When it is larger, the homogeneity of the polymer cannot be said to be sufficient, which is not preferable. The liquid crystalline resin is a polyester and / or polyester amide capable of forming an anisotropic molten phase when melted, and is, for example, a wholly aromatic liquid crystalline polyester having a naphthalene ring, or a wholly aromatic liquid crystal having a naphthalene ring. It may be a liquid crystalline polyesteramide, a liquid crystalline polyester having an ethylenedioxy unit, or a liquid crystalline polyesteramide having an ethylenedioxy unit.

Preferable examples of the liquid crystalline polyester include a liquid crystalline polyester composed of the structural units (I), (III) and (IV), and a liquid crystal composed of the structural units (I), (II) and (IV). Polyester and (I), (II), (II
A liquid crystalline polyester comprising the structural units I) and (IV) can be mentioned. The structural unit (I) is a structural unit of polyester produced from p-hydroxybenzoic acid, and (II) is 4,4'-dihydroxybiphenyl,
3,3 ', 5,5'-tetramethyl-4,4'-dihydroxybiphenyl, hydroquinone, t-butylhydroquinone, phenylhydroquinone, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene,
A structural unit produced from an aromatic dihydroxy compound selected from 2,2-bis (4-hydroxyphenyl) propane and 4,4′-dihydroxydiphenyl ether, a structural unit (III) is a structural unit produced from ethylene glycol, Structural unit (IV) is terephthalic acid, isophthalic acid, 4,4'-diphenyldicarboxylic acid, 2,6'-
Naphthalenedicarboxylic acid, 1,2-bis (phenoxy)
Ethane-4,4'-dicarboxylic acid, 1,2-bis (2-
A structural unit formed from an aromatic dicarboxylic acid selected from chlorophenoxy) ethane-4,4'-dicarboxylic acid and 4,4'-diphenyletherdicarboxylic acid is shown. Of these, R ₁

[0012]

Embedded image And R ₂ is

[0013]

[Chemical 6] Are particularly preferred. In addition to the above structural units (I)-(IV), p-
Polyesteramides which form an anisotropic melt phase containing p-iminophenoxy units formed from aminophenol are preferred.

The liquid crystalline polyester which can be preferably used in the present invention is the above-mentioned structural unit (I), (II) and (IV) or a copolymer composed of (I), (II), (III) and (IV). The amount of copolymerization of the above structural units (I), (II), (III) and (IV) is arbitrary. However, from the viewpoint of fluidity, the following copolymerization amount is preferable. That is, when the structural unit (III) is included, the structural unit [(I) + (II)] is [(I) + from the viewpoint of heat resistance, flame retardancy and mechanical properties.
(II) + (III)] is preferably 60 to 95 mol%, 7
5 to 93 mol% is more preferable. Also, the structural unit (III)
Is preferably 40 to 5 mol% of [(I) + (II) + (III)], and more preferably 25 to 7 mol%. Further, the molar ratio of the structural unit (I) / (II) is preferably 75/25 to 95/5, more preferably 78/22 to 93/7 from the viewpoint of the balance between heat resistance and fluidity. The structural unit (IV) is substantially equimolar to the structural unit [(II) + (III)].

On the other hand, when the structural unit (III) is not contained, the structural unit (I) is [(I) + (I
I)] is preferably 40 to 90 mol%, and 60
It is particularly preferable that the content of the structural unit (I
V) is substantially equimolar to the structural unit (II). In addition,
In the polycondensation of the above liquid crystal polyester which can be preferably used in the present invention, in addition to the components constituting the structural units (I) to (IV), 3,3′-diphenyldicarboxylic acid, 2,
Aromatic dicarboxylic acids such as 2'-diphenyldicarboxylic acid, aliphatic dicarboxylic acids such as adipic acid, azelaic acid, sebacic acid, dodecanedioic acid, alicyclic dicarboxylic acids such as hexahydroterephthalic acid, chlorohydroquinone, methylhydroquinone, Aromatic diols such as 4,4'-dihydroxydiphenyl sulfone, 4,4'-dihydroxydiphenyl sulfide and 4,4'-dihydroxybenzophenone, 1,4-butanediol, 1,6
-Hexanediol, neopentyl glycol, 1,4
Aliphatic and alicyclic diols such as cyclohexanediol and 1,4-cyclohexanedimethanol, and aromatic hydroxycarboxylic acids such as m-hydroxybenzoic acid and 2,6-hydroxynaphthoic acid, and p-aminophenol, p-amino Benzoic acid and the like can be further copolymerized in a small proportion within a range that does not impair the object of the present invention.

For example, in the production of the above-mentioned preferably used liquid crystalline polyester, when the above structural unit (III) is not contained, the following (1) and (2) are produced, and when the structural unit (III) is contained, (3) is produced. A preferable method is a method. (1) Deacetic acid polycondensation reaction of p-acetoxybenzoic acid and a diacylated aromatic dihydroxy compound such as 4,4′-diacetoxybiphenyl and 4,4′-diacetoxybenzene with an aromatic dicarboxylic acid such as terephthalic acid. How to manufacture by.

(2) p-hydroxybenzoic acid and 4,
A method in which an aromatic dihydroxy compound such as 4'-hydroxybiphenylhydroquinone or an aromatic dicarboxylic acid such as terephthalic acid is reacted with acetic anhydride to acylate a phenolic hydroxyl group, and then a deacetic acid polycondensation reaction is performed. (3) by the method of (1) or (2) in the presence of a polyester polymer such as polyethylene terephthalate, an oligomer, or a bis (β-hydroxyethyl) ester of an aromatic dicarboxylic acid such as bis (β-hydroxyethyl) terephthalate. Method of manufacturing.

Although these polycondensation reactions proceed without a catalyst, when it is preferable to add a metal compound such as stannous acetate, tetrabutyl titanate, potassium acetate and sodium acetate, antimony trioxide, or magnesium metal. is there. Some of the liquid crystalline resins (A) in the present invention are capable of measuring logarithmic viscosity in pentafluorophenol, and in that case, the concentration is 0.1 g / dl at 60 ° C.
It is preferably 0.5 dl / g or more as measured by 1., particularly preferably 1.0 to 3.0 dl / g when the structural unit (III) is contained, and 2. when the structural unit (III) is not contained. 0 to
10.0 dl / g is preferred.

The melt viscosity of the liquid crystalline resin (A) in the present invention is preferably 10-20,000 poise, and more preferably 20-10,000 poise. In the present invention, carbon black can be further blended, and the carbon black that can be used is not particularly limited, but the pH is preferably 3 to 10 from the viewpoint of mechanical properties of the obtained composition, Those having 5 to 9 are particularly preferably used.

Examples of the olefin polymer used in the present invention include polyethylene, polypropylene, a copolymer of ethylene and an α-olefin having 3 or more carbon atoms, and a copolymer of propylene and an α-olefin having 4 or more carbon atoms. , One or more selected from a copolymer consisting of ethylene, an α-olefin having 3 or more carbon atoms and a non-conjugated diene.

The α-olefin having 3 or more carbon atoms is preferably propylene, butene-1, pentene-.
1,3-methylpentene-1, octacene-1, etc. are more preferable, and propylene and butene-1 are more preferable, and these can be used in combination of two or more kinds. Examples of the α-olefin having 4 or more carbon atoms include those excluding propylene from the above α-olefins having 3 or more carbon atoms, and these can be used in combination of two or more kinds.

The non-conjugated diene is preferably 5-ethylidene-2-norbornene, dicyclopentadiene,
1,4-hexadiene or the like can be used. The copolymerization ratio of ethylene and the α-olefin having 3 or more carbon atoms is usually 40/60 to 99/1 (molar ratio), preferably 70 in the copolymer comprising ethylene and the α-olefin having 3 or more carbon atoms. / 30 to 95/5 (molar ratio).

The copolymerization amount of ethylene in the copolymer consisting of ethylene, an α-olefin having 3 or more carbon atoms and a non-conjugated diene is usually 5 to 96.9 mol%, preferably 30 to 84.5 mol%. And α- having 3 or more carbon atoms
The co-weight of the olefin is usually 3 to 80 mol%, preferably 15 to 60 mol%, and the co-polymerization amount of the non-conjugated diene is usually 0.1 to 15 mol%, preferably 0.5 to
It is 10 mol%. The copolymerization amount of propylene in the copolymer consisting of propylene and an α-olefin having 4 or more carbon atoms and a non-conjugated diene is usually 5 to 96.0 mol%, preferably 30 to 84.5 mol%. And the copolymerization amount of the α-olefin having 3 or more carbon atoms is usually 3 to
It is 80 mol%, preferably 15 to 60 mol%, and the copolymerization amount of the non-conjugated diene is usually 0.1 to 15 mol%, preferably 0.5 to 10 mol%.

Specific examples of these copolymers include ethylene / propylene copolymers, ethylene / butene-1 copolymers, ethylene / pentene-1 copolymers, ethylene / propylene / butene-1 copolymers, propylene. / Penten-
1 copolymer, propylene / butene-1 copolymer, ethylene / propylene / 5-ethylidene-2-norbornene copolymer, ethylene / propylene / 1,4-hexadiene copolymer, propylene / butene, 1/1, It is a 4-hexadiene copolymer, an ethylene / propylene / dicyclopentadiene copolymer, and the like. Among them, an ethylene / propylene copolymer and an ethylene / butene-1 copolymer are more preferable because of excellent heat resistance.

Two or more kinds of the above olefin polymers can be used in combination. The weight average molecular weight of the olefin polymer is 10,000 to 600,000, preferably 3,000.
0-500000, more preferably 100000-4
It is preferably in the range of 50,000. The addition amount of the olefin polymer is preferably 0.05 to 10 parts by weight, and particularly preferably 0.1 to 2 parts by weight.

In the present invention, an organic bromine compound can be further blended, and as the organic bromine compound which can be used, a known organic bromine compound which is usually used as a flame retardant is included, and particularly, the bromine content is 20% by weight. The above is preferable. Specifically, hexabromobenzene, pentabromotoluene, hexabromobiphenyl, decabromobiphenyl, hexabromocyclodecane, decabromodiphenyl ether, octabromodiphenyl ether, hexabromodiphenyl ether, bis (pentabromophenoxy) ethane, ethylene bis (tetrabromo Phthalimide), a polycarbonate oligomer produced from tetrabromobisphenol A as a raw material or a copolymer thereof with bisphenol, a brominated epoxy compound (for example, a monoepoxy compound obtained by the reaction of brominated bisphenol A and epichlorohydrin), poly (bromine) Benzyl acrylate), brominated polyphenylene ether, condensate of brominated bisphenol A cyanur and brominated phenol, brominated Examples include halogenated polymers and oligomers such as styrene, cross-linked brominated polystyrene, cross-linked brominated poly α-methylstyrene, and mixtures thereof. Among them, ethylene bis (tetrabromophthalimide), brominated epoxy oligomer or polymer, Brominated polystyrene, crosslinked brominated polystyrene, brominated polyphenylene ether and brominated polycarbonate are preferred, with brominated polystyrene being most preferred. The above preferable organic bromide will be described in more detail. Examples of the brominated epoxy polymer include those represented by the following general formula (i).

[0027]

[Chemical 7]

The degree of polymerization n in the above general formula (i) is preferably 15 or more, more preferably 50 to 80. As the brominated polystyrene used in the present invention, brominated polystyrene and cross-linked brominated polystyrene produced by brominating polystyrene obtained by radical polymerization or anionic polymerization, or radical polymerization or anionic polymerization of brominated styrene monomer, preferably Is produced by radical polymerization (ii) and / or (ii
Examples thereof include polybrominated styrene having a brominated styrene unit represented by the formula (i), and particularly a structural unit represented by the following formula (ii) and / or (iii) produced from a brominated styrene monomer as a main constituent. Polybrominated styrene having a weight average molecular weight of 1 × 10 ^{3 to} 120 × 10 ⁴ as a component is preferable.

[0029]

Embedded image Brominated styrene monomer here means styrene monomer 1
Those having 2-3 bromine atoms introduced into the aromatic ring by a substitution reaction are preferable per one, and monobrominated styrene and the like may be contained in addition to dibrominated styrene and / or tribrominated styrene. .

The above polybrominated styrene preferably contains dibrominated styrene and / or tribrominated styrene units in an amount of 60% by weight or more, more preferably 70% by weight or more. In addition to dibrominated styrene and / or tribrominated styrene, polybrominated styrene obtained by copolymerizing 40% by weight or less, preferably 30% by weight or less of monobrominated styrene may be used. The weight average molecular weight of this polybrominated styrene is more preferably 1 × 10 ⁴ to 15 × 10 ⁴ . The weight average molecular weight is a value measured using a gel permeation chromatograph and is a relative value based on polystyrene molecular weight.

The crosslinked brominated polystyrene is preferably polystyrene obtained by brominated porous polystyrene crosslinked with divinylbenzene. As the brominated polycarbonate, those represented by the following general formula (iv) are preferable.

[0032]

[Chemical 9] (R ₁ and R ₂ represent a substituted or unsubstituted aryl group, and a pt-butylphenyl group is most preferable.) The polymerization degree n in the general formula (iv) is preferably 4 or more, and 8 The above, especially 8 to 25 can be used more preferably.

The amount of the organic bromide compounded is 0.5 to 60 parts by weight, especially 1 to 100 parts by weight of the liquid crystalline resin.
30 parts by weight is preferred. In the liquid crystalline resin molded product of the present invention, the organic bromide is preferably dispersed in the resin composition before molding with an average diameter of 25 μm or less.
The dispersion is more preferably 0 μm or less.

[0034]

【Example】

Example 1 22.1 kg of p-hydroxybenzoic acid and 4,4 'were placed in a reaction can.
-Preparation of 2.7 kg of dihydroxybiphenyl, 4.8 kg of polyethylene terephthalate, 2.5 kg of terephthalic acid and 21.3 kg of acetic anhydride, the temperature inside the reaction vessel was set to 130 to 250 ° C over 5 hours, and stirring was continued at 250 ° C for 30 minutes. It was The amount of distillate at this point was 20.3 kg, which was 82% of the theoretical amount of distillate. Thereafter, the reaction product was transferred to a polymerization vessel, the temperature inside the vessel was adjusted to 250 to 315 ° C over 2 hours, the polymerization vessel was depressurized to 250 Torr over 70 minutes, and the depressurization degree was adjusted to 2
The stirring was continued for 1 hour while maintaining at 50 Torr. Then 50
The pressure was reduced to 1 Torr over minutes, and stirring was continued for 2 hours to complete polycondensation. Thereafter, the inside of the polymerization vessel was pressurized to 4 kg / cm ² , and then the polymer was discharged in a strand form through the die. The theoretical structural formula of the obtained liquid crystalline polyester is as follows.

[0035]

[Chemical 10] k / l / m / n = 80 / 7.5 / 12.5 / 20 This liquid crystalline polyester is manufactured by DS manufactured by Perkin Elmer.
When the melting point and the melting point width were measured using the C-7 type under the above-mentioned conditions, the peak temperature of Tm ₁ was 316 ° C. and Tm ₂
Had a peak temperature of 314 ° C and a melting point range of 20 ° C.
When the following formula (2) is calculated with Tm ₂ as Tm, it is 3.0
° C.

Tm-0.0769x ² + 8.20x-401.5 (2) Further, with respect to 100 parts by weight of this polymer, 10 parts by weight of polydibrominated styrene (bromine content 59%), fiber diameter About 9
After 45 parts by weight of glass fibers having a diameter of 3 μm and a fiber length of 3 mm were dry blended, they were melt-kneaded and pelletized at 325 ° C. by a 30 mmφ twin-screw extruder.

The pellets thus obtained were subjected to a Sumitomo Nestal injection molding machine Promat (manufactured by Sumitomo Heavy Industries, Ltd.), and a combustion test piece (1/64 inch × 1) under the conditions of a cylinder temperature of 325 ° C. and a mold temperature of 90 ° C. / 2 inch x 5 inch) was molded. When a vertical combustion test was conducted on this test piece in accordance with UL94 standard, it was found to be VO and non-drip. Further, as an evaluation of fluidity, the flow length (bar flow length) of a 0.5 mm thick × 12.7 mm wide test piece was measured under the conditions of an injection speed of 99% and an injection pressure of 500 kgf / cm ² using the above molding machine. I asked.

As a result, the rod flow length was 120 mm, indicating good fluidity. The pellet was used to form the lens holder shown in FIGS. 1 and 2 under the same molding conditions. Then, when the magneto-optical head is mounted on a carriage and mounted on a floppy disk drive device using aluminum die-cast as a chassis, and the position of the magneto-optical head on the chassis at 23 ° C. is used as a reference point, the magneto-optical head at −10 to 70 ° C. The maximum deviation from the reference point was less than 0.1 μm. Comparative Example 1 Using the same device as in Example 1, deacetic acid polymerization was carried out under the following conditions. First, p-hydroxybenzoic acid 20.
17 kg, 3-hydroxy-6-naphthoic acid 10.16 kg
And 22.44 kg of acetic anhydride were charged, and it took 1 hour over 5 hours.
The temperature was adjusted to 30 to 230 ° C., and the polymerization vessel was depressurized to 1 Torr over 90 minutes. Then, stirring was continued for 1 hour to complete polycondensation.
The theoretical structural formula of the obtained liquid crystalline polyester is as follows.

[0039]

[Chemical 11] This liquid crystalline polyester is a DS manufactured by Perkin Elmer
When the melting point and the melting point width were measured using the C-7 type under the above-mentioned conditions, the peak temperature of Tm ₁ was 288 ° C., the peak temperature of Tm ₂ was 280 ° C., and the temperature width was 36 ° C. In addition, the fiber diameter is about 9μ for 100 parts by weight of this polymer.
After 45 parts by weight of glass fibers having a length of m and a fiber length of 3 mm were dry blended, they were melt-kneaded and pelletized at 280 ° C. by a 30 mmφ twin-screw extruder. The pellets thus obtained were molded in the same manner as in Example 1, and the rod flow length was determined to be 81 mm.
Was worse than.

A lens holder was molded using the pellets in the same manner as in Example 1, and the deviation from the reference point was measured. The maximum value was -1.5 μm, which was larger than that in Example 1.

[0041]

Since the optical pickup lens holder of the present invention is made of a specific liquid crystal resin composition, it can be accurately molded even if it has a complicated structure and a thin portion. As a result, it is possible to provide an optical pickup having an extremely small thickness and good responsiveness.

[Brief description of drawings]

FIG. 1 is a schematic plan view of an optical pickup lens holder of the present invention.

FIG. 2 is a schematic side view of the optical pickup lens holder of the present invention.

FIG. 3 is a schematic sectional view of an optical pickup lens holder of the present invention.

[Explanation of reference numerals] 1,1 'lens holder 2,2' lens 3 reflecting member 4 light emitting element 5 diffraction grating 6 light receiving element

Claims (7)

[Claims] 1. A UL-94 having a thickness of 1/64 inch, which is composed of a composition containing a liquid crystalline resin (A) having a melting point width of 30 ° C. or less as determined by a differential scanning calorimeter and an inorganic filler (B) as main components. Optical pickup lens holder with V-O flame retardant performance. 2. The optical pickup lens according to claim 1, wherein the composition further comprises 0.01 to 10 parts by weight of carbon black based on 100 parts by weight of the liquid crystalline resin (A). holder. 3. The composition further comprises polyethylene, polypropylene, a copolymer of ethylene and an α-olefin having 3 or more carbon atoms, 100 parts by weight of the liquid crystalline resin (A), propylene and 4 or more carbon atoms. Copolymer consisting of α-olefin, copolymer consisting of ethylene and α-olefin having 3 or more carbon atoms and non-conjugated diene, and copolymer consisting of propylene and α-olefin having 4 or more carbon atoms and non-conjugated diene 2. The light according to claim 1, which comprises 0.01 to 10 parts by weight of an olefin polymer having a weight average molecular weight of 10,000 to 600,000, which is one or more kinds selected from the group consisting of: Pickup lens holder. 4. The light according to claim 1, wherein the composition further comprises 0.5 to 60 parts by weight of an organic bromide per 100 parts by weight of the liquid crystalline resin (A). Pickup lens holder. 5. An organic bromide having a weight average molecular weight of 1 × 10 ^{3 to} 120 × 10 ⁴ containing at least one of the following structural units (X) produced from brominated styrene monomer as a main constituent.
5. The polybrominated styrene of
Optical pickup lens holder described. Embedded image 6. A liquid crystalline resin (A) selected from a liquid crystalline polyester having an ethylenedioxy unit and a liquid crystalline polyesteramide having an ethylenedioxy unit.
The optical pickup lens holder according to claim 1, wherein the optical pickup lens holder is made of at least one kind of liquid crystalline resin. 7. A liquid crystalline polyester comprising (A) a liquid crystalline resin comprising the following structural units (I), (III) and (IV):
One or more selected from liquid crystalline polyesters composed of structural units (I), (II) and (IV) and liquid crystalline polyesters composed of structural units (I), (II), (III) and (IV) The optical pickup lens holder according to claim 6, wherein Embedded image (However, R ₁ in the formula is It represents one or more groups selected from, R ₂ is embedded image And one or more groups selected from Further, in the formula, X represents a hydrogen atom or a chlorine atom, and the structural unit [(II) + (II
I)] and structural unit (IV) are substantially equimolar. )