JPS63229404A - Polarizing film - Google Patents

Abstract

PURPOSE:To obtain the titled film having good polarizing property and excellent moisture-resistivity and heat-resistivity by using a conjugated high polymer having specified dichroism for the tilted film. CONSTITUTION:The conjugated high polymer has moldability and is soluble to a solvent and is produced from the conjugated high polymer precursor which is to be the conjugated high polymer by releasing treatment, and is uniaxially orientated, and has the dichroism and is shown by formula I. The conjugated high polymer is used for the titled film. In formula I, X is sulfur or oxygen atom, R1 and R2 are each hydrogen or halogen atom, 1-4C alkyl, nitrile, the same or the different group selected from halogen or trihalomethyl group, (n) is an integer of >=5. The usable conjugated high polymer is not specified to one kind thereof, and as necessary, the plural kinds of the high polymer may be used at the same time. Thus, the titled film having the excellent durability under a thin high temp. and humidity and the good durability against chemicals is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a polarizing film using conjugated intersystem molecules.

<Prior Art and Problems> At present, polarizing films are produced by dehydrochlorination of stretched and oriented polyvinyl alcohol (hereinafter abbreviated as PVA) or its derivatives, or polyvinyl chloride (hereinafter abbreviated as PvC) or dehydration of PvA-based films. A polyene-based polarizing film 1 in which polyene is produced and oriented is manufactured by adsorbing iodine or dichroic dye as a polarizing element.

Among these, polarizing films that use wax as a polarizing element have excellent initial polarization performance, but are weak against water and heat, and have problems with their durability when used for long periods of time in high temperature and high humidity conditions. There is. When using PVA, methods such as strengthening the treatment with an aqueous solution containing formalin or hydrochloric acid and using a polymer film with low moisture permeability as a protective film have been considered in order to improve its durability.・Durability is insufficient in high humidity conditions.

Furthermore, although polarizing films using dichroic dyes as polarizing elements have improved moisture resistance and heat resistance compared to polarizing films using iodine, PV i% is 1% higher than that of the base film.
．． However, it is still not perfect.

The purpose of the present invention is to solve the above-mentioned problems of conventional polarizing films and to provide a side light film that has good polarizing performance and excellent moisture resistance and durability. be.

Means for solving one problem> The present invention was completed as a result of several studies in order to solve the above problem. The conventional illumination optical film in which dyes are absorbed and oriented is A, and instead of these dyes, a polymer (conjugated polymer precursor ), and by performing an appropriate elimination treatment such as heat treatment [In the above formula fIl, R is the same or different substituent selected from a group, a nitrile group, a trihalomethyl group, and a trihalomethyl group;
, and R6 are the same or different substituents selected from a hydrogen atom or an alkyl group having 1 to 4 carbon atoms,
Z- is an anion, and n is an integer of 6 or more. ] The present invention relates to a polarizing film characterized by using a conjugated polymer having dichroism shown in its composition.

[In the above formula (Ill), X is a sulfuric acid f- or an oxygen atom, and R1 and R8 are the same or are different substituents,
n is an integer of 6 or more. ] In particular, poly-thiophene vinylene (hereinafter abbreviated as PTV), which is soluble in a solvent represented by formula m) or formula W) in which the sulfonium base of the weapon is replaced with an alkoxy group, is used through heat treatment etc. [The above-mentioned formula bait] is obtained from ζ by performing an appropriate desorption treatment, and n is an integer of 6 or more.

Furthermore, in the above formula (2), R is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. ] A formula with dichroism (Vl
The present invention relates to a polarizing film characterized by using the conjugated polymer PTV shown in the following.

[In the formula (ma), n is an integer of 5 or more. ] The polarized light beam of the present invention can be obtained in the embodiments described below. That is, a conjugated polymer precursor soluble in a solvent represented by the formula (Il, Q[) or (ff) of (1) is formed into a film using a solution flow abrasive method, and the conjugated polymer precursor is By performing an orientation treatment to make it highly uniaxially oriented, and by performing an appropriate desorption treatment such as heat treatment during or after the orientation, a highly uniaxially oriented dichroism (V) can be obtained. A polarizing film using the conjugated polymer shown in can be obtained. At this time, by controlling the thickness so that the light absorption rate becomes an appropriate value, a light-opening film with excellent performance can be obtained.

Furthermore, the following method can be used to substantially control the thickness of the conjugated polymer.

(2) A base polymer film that swells or has solubility in a solvent, in which a conjugated polymer precursor represented by formula (I), 1110, or (IV) is dissolved in a solvent. A composite film of the conjugated polymer precursor and the base polymer is created by adsorption using the lζ dipping method. Next, by stretching the composite film uniaxially, the conjugated polymer precursor is highly uniaxially oriented. During and after stretching, excellent polarizing films using dichroic weapons or conjugated polymers such as (v) 1 can be obtained by performing a first-class desorption treatment such as heat treatment. It will be done.

1' TV yft for A6 case, PVC, PVA
, ethylene vinyl alcohol copolymer (hereinafter referred to as saponified E/
A base polymer film made of a thermoplastic resin such as VA), polysulfone (hereinafter referred to as PSf), or polycarbonate (hereinafter referred to as PC) is used as a PTV precursor 1 to 8 of the formula σ). After crushing in dimethylformamide (hereinafter abbreviated as L) MF) solution and drying in a nitrogen gas atmosphere, 0.5% was added to the base polymer film.
~1.6μm PTV precursor film adsorbs nine PTVs
Create a composite film of precursor and base polymer. The films are then heated to a suitable temperature, i.e. PV
For A go-tooc,)'VC's 4 go 70-120
℃, 6O-10 (1) in the case of M-ized EVA (7), polished at a temperature of 160 to 220℃ for PSf, and 140 to 180℃ for PC to 8 times or more, preferably 4 times or more, and then An excellent polarizing film can be obtained by performing heat treatment at a temperature of 100 to 200C, which is selected depending on the heat resistance of the material film.

(8) Formula 9 CI), all or (ff
Dissolve the conjugated polymer precursor that can be dissolved in the solvent shown in Then, a composite film of the conjugated polymer precursor and the base polymer is created by a solution flow method. Next, by stretching the composite film uniaxially, the conjugated polymer precursor is highly uniaxially oriented. By performing an appropriate elimination treatment such as heat treatment during or after stretching, a dichroic formula ([
An excellent polarizing film using the conjugated polymer shown in No. 11 or (ma) can be obtained.

When using PTV, make a 10-20% by weight solution of a resin soluble in DMF, such as PSf, and add the PTV precursor shown on the left side to PSf in a proportion of 0.8-2%, preferably 0.5-20% by weight. 1 wt.
A composite film of ~200μm F''TV precursor and PSf is formed. Next, an excellent polarizing film is obtained by stretching at a temperature of 160 to 220C by at least 3 times, preferably at least 4 times, and simultaneously heat-treating it. can get.

Furthermore, the conjugated polymer used in the present invention is not limited to one type, but a plurality of types can be used simultaneously as necessary. That is, after a composite film of a conjugated polymer precursor and a base polymer is created by a solution flow method, etc., the base polymer film becomes 1! Conjugated polymer 1 dissolved in 1 solvent that dissolves or has solubility
A composite film of two types of conjugated polymer precursors and a base polymer is created by adsorbing the No. 11 precursor by a dipping method, and then an appropriate desorption process such as stretching and heat treatment is performed to separate the two types of polymers. By appropriately combining the above methods (11 to (8)), such as obtaining a polarizing film using a conjugated polymer having multiple dichroisms, a polarizing film using a conjugated polymer having multiple dichroisms can be obtained. can get.

Furthermore, the above (11, (21 and (8)
) By performing so-called doping in which an electron-withdrawing compound or an electron-donating compound (hereinafter referred to as a dopant) is added to a polarizing film obtained by a method such as
The electronic state of the conjugated polymer can be changed, thereby producing a polarizing film with a changed light absorption region, that is, a changed color. Examples of dopants that can be used in the present invention include iodine, ferric chloride, arsenic trifluoride, sulfur dioxide, sulfuric acid, sodium, lithium, and the like.

When PTV is used, the color can be stably changed by doping with sulfuric acid.

Poly-phenylene vinylene (hereinafter referred to as P) obtained by polymerizing baraxylylene-bisdialkylsulfonium halide
It is a conjugated polymer obtained by creating a composite film of PPV precursor and PC by casting an aqueous solution of the precursor (abbreviated as PV) onto a PC film, and then stretching and heat-treating it at 160'C. A polarizing film exhibiting a neutral color can be obtained by doping a yellow dawn film using PPV with sulfuric acid, but this film has the drawbacks of being easily discolored and having insufficient stability. On the other hand, by doping the PTV@optical film prepared by the method shown in (2) Iζ above with sulfuric acid, the light absorption region expands to the long wavelength side and at the same time
A polarizing film is obtained which exhibits high durability in that the polarizing performance does not change over a long period of 1000 hours or more in a durability test under high temperature and high humidity conditions of 5° C. and 90% RH.

In addition, the polarizing film using the conjugated polymer prepared by the above method can be immersed in a dichroic dye solution, or the dichroic dye can be adsorbed by one or more conjugated polymers. A liquid containing a base polymer and a dichroic dye dissolved in IM or a plurality of dichroic dyes as needed in an appropriate ratio is mixed and formed into a film using a solution casting method, followed by stretching, heat treatment, etc. By combining dichroic dyes with the methods shown in (11 to (8) above), such as performing appropriate desorption treatment, a polarizing film containing a combination of conjugated polymers and dichroic dyes can be obtained. The dye used may be a conjugated polymer or its precursor, or any dye that is compatible with the base polymer used and has a high dichroic ratio, but azo dyes may be used. , anthraquinone dyes, quinophthalone dyes, perylene dyes, naphthoquinone dyes, tetrazine dyes, etc. can be used.

Note that it is possible to highly uniaxially align conjugated polymers having dichroism or (ma)1ζ, and when using dichroic dyes, the conjugated polymer and dichroic As long as any of the dyes can be highly oriented, the method for producing a polarizing film of the present invention is not necessarily limited to the above range.

The present invention may be a film of a conjugated polymer having dichroism shown in formula (■) or (ma) alone, or a conjugated polymer may be used with another base polymer 1ζ, multiplication, '- or lI
! In the latter case, the base polymers used include pvci or its derivatives, PVA or its derivatives, cellulose acetate or its derivatives, saponified EVk (D et al., PSf, PC,
Examples include heat-resistant films such as polyetherimide and polyethersulfone.

In addition, the base polymer is not limited to these polymers, and any material can be used as long as it is possible to uniaxially align a conjugated polymer with dichroism using the method described above. It's okay.

Among these, it is more preferable to use a heat-resistant film such as PSf in terms of improving the durability of the polarizing film of the present invention.

In the present invention 1, a film consisting solely of a conjugated polymer precursor represented by formula (I), [lH or (ff), or a composite film consisting of a conjugated polymer precursor and a base polymer, etc. As a method for stretching the film to this point, any method suitable for the film to be stretched, such as dry uniaxial stretching, wet uniaxial stretching, or roll rolling, may be used.

By the above method, a polarizing film using a conjugated polymer having dichroism can be obtained, but the light resistance and heat resistance are further improved by 1ζ.
It may be possible to add additives such as ultraviolet absorbers and stabilizers as necessary to strengthen the polarizing film.Also, it is possible to add protective films, quarter-wave plates, etc. to these polarizing films in a circle at 74 degrees horizontally. When using it as a polarizing plate, etc., add these additives to a protective film or a quarter-wave plate, or apply the above polarizing film and an adhesive to bond them together, or paste it on a liquid crystal panel. It is also possible to add it to the viscous*EQ@ for mixing.

(Examples) The present invention will be explained in more detail with reference to Examples below, but these are merely illustrative and the present invention is not limited thereto.

In addition, the degree of polarization in the present invention refers to the degree of polarization obtained by preparing two polarizing films and measuring the light transmittance with the two films superimposed. It is a value.

Here, Hll is a value (called parallel light transmittance) measured when two polarizing films are stacked so that the orientation directions of the polarizing films are in the same direction, and H The above is a value (referred to as orthogonal light transmittance) measured when two polarizing films are superimposed so that the orientation directions of the polarizing films are orthogonal to each other.

Note that the average shown in the examples refers to l in the wavelength range shown.
It is the average of the values measured for each Qnm.

Example 1 A 45 μm PPv precursor film is prepared by a solution casting method from a PPv precursor aqueous solution obtained by polymerization of baraxylylene-bisdialkylsulfonium halide.

Next, a DMF solution of a PTV precursor in which R3 shown in ffl is a methyl group is cast onto the PPv precursor film core (ffl) to form a 0.6 μm PTV precursor film. A PPv-PTV precursor composite film is created.Then, it is stretched 6 times at a temperature of up to 140°C and heat-treated at 170°C for 80 minutes to form a PPv-PT precursor composite film.
A polarizing film is obtained using the V composite film. The performance is as shown below.

Example 2 A Ps f-PTV precursor body film was prepared by mixing PSf with a DMFI solution (Vl fc: 6R, #) and applying the solution flow method to 120 μm under conditions of 100° C. for 80 minutes. Next, the film is uniaxially stretched by 4 times while being heat treated in vacuum at about 180°C; thereby, a dawning film made of a 40 μm PSf-PTv composite film is obtained. The performance is as shown below.

This polarizing film: 100°C-too.

Durability tests were conducted for 1000 hours and 81)C-90%RH, but no deterioration in performance was observed.

<Effects of the Invention> The present invention has excellent durability under conditions of high temperature and high humidity.
In addition, a polarizing film with good durability against chemicals was obtained. The polarizing film of the present invention has a significantly wide range of applicable environmental conditions, and can be used in applications that require durability over a wide temperature and humidity range, such as in-vehicle liquid crystal display elements and anti-glare filters. .

Furthermore, for single-light films made of conjugated polymers alone or composite films with heat-resistant, heat-and-moisture-resistant films using conjugated polymers with dichroism such as formula (■) or ffl, protection is required. No need for membranes or support membranes, etc.
It contributes to the simplification of the polarizing film manufacturing process and cost reduction, and is also industrially useful.

Claims (1)

[Scope of Claims] (1) A uniaxially oriented material obtained from a conjugated polymer precursor that has shape-forming properties, is soluble in a solvent, and becomes a conjugated polymer upon desorption treatment. A polarizing film comprising a conjugated polymer represented by formula (1) having dichroism. ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (1) [In the above formula (1), the same or different substituents selected from a halogen group or a trihalomethyl group,
n is an integer of 5 or more. (2) The polarizing film according to claim 1, wherein the conjugated polymer having dichroism is poly-thiophene vinylene represented by formula (2). ▲There are mathematical formulas, chemical formulas, tables, etc.▼(2) [In the above formula (2), n is an integer of 5 or more. ] (8)
It is characterized by using a uniaxially oriented conjugated polymer obtained by adsorbing, laminating, or mixing the conjugated polymer precursor on another base polymer film and then performing uniaxial alignment and desorption treatment. A polarizing film according to claim 1. (4) The polarizing film according to claim 1, wherein the dichroic conjugated polymer is blended with an electron-withdrawing compound or an electron-donating compound. (5) The polarizing film according to claim 1, wherein a dichroic dye is blended into the conjugated polymer having dichroism.