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GB1596011A - Aromatic dicarboxylic esters useful as liquid crystal substances - Google Patents

Aromatic dicarboxylic esters useful as liquid crystal substances Download PDF

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Publication number
GB1596011A
GB1596011A GB35278A GB35278A GB1596011A GB 1596011 A GB1596011 A GB 1596011A GB 35278 A GB35278 A GB 35278A GB 35278 A GB35278 A GB 35278A GB 1596011 A GB1596011 A GB 1596011A
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United Kingdom
Prior art keywords
cnh2n
crystalline
liquid
substances
liquid substances
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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.)
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GB35278A
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WERK fur FERNSEHELEKTRONIK VEB
Werk fuer Fernsehelektronik GmbH
Original Assignee
WERK fur FERNSEHELEKTRONIK VEB
Werk fuer Fernsehelektronik GmbH
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Publication of GB1596011A publication Critical patent/GB1596011A/en
Expired legal-status Critical Current

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    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09KMATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K19/00Liquid crystal materials
    • C09K19/04Liquid crystal materials characterised by the chemical structure of the liquid crystal components, e.g. by a specific unit
    • C09K19/06Non-steroidal liquid crystal compounds
    • C09K19/08Non-steroidal liquid crystal compounds containing at least two non-condensed rings
    • C09K19/30Non-steroidal liquid crystal compounds containing at least two non-condensed rings containing saturated or unsaturated non-aromatic rings, e.g. cyclohexane rings
    • C09K19/3001Cyclohexane rings
    • C09K19/3066Cyclohexane rings in which the rings are linked by a chain containing carbon and oxygen atoms, e.g. esters or ethers
    • C09K19/3068Cyclohexane rings in which the rings are linked by a chain containing carbon and oxygen atoms, e.g. esters or ethers chain containing -COO- or -OCO- groups

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  • Chemical & Material Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Organic Chemistry (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Liquid Crystal Substances (AREA)
  • Liquid Crystal (AREA)

Abstract

Tricyclic cyclohexanecarboxylic acids or cyclohexyl esters of the formula <IMAGE> in which R<1> = CnH2n+1, where n = 1 to 9, R<2> = CnH2n+1-, CnH2n+1O-, CnH2n+1COO-, CnH2n+1 OCOO-, where n = 1 to 9, -CN, -Cl, -Br or -C2H4CN, X = <IMAGE>, R<3> = H, -CH3, -C2H5, -Cl, -Br, -CN or -CH2CN, R<4> = CnH2n+1- or CnH2n+1O-, where n = 0 to 9. As liquid-crystalline substances and/or as essential constituents of mixtures, these compounds have high chemical and thermal stability, no inherent colour, relatively high clearing points at the same time as sufficiently low melting points, and low viscosity values. The liquid crystals can be used both for the production of opto-electronic components and as an orienting (aligning) medium in spectroscopy and in gas chromatography.

Description

(54) AROMATIC DICARBOXYLIC ESTERS USEFUL AS LIQUID CRYSTAL SUBSTANCES (71) We, VEB WERK FijR FERNSEHELEKTRONIK, a corporation organised under the laws of the German Democratic Republic, of 1--5 Ostendstrasse, Berlin-Obersch6neweide, German Democratic Republic, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- The invention relates to the use of crystalline-liquid nematic substances in electro-optical arrangements for the modulation of the transmitted or incident light and for the reproduction of digits, signs and images, also as orienting medium for spectroscopy and gas chromatography.
Characteristics of the Known Technical Solutions It is known that nematic liquid crystals can be reoriented in electric fields and thus are usable for the production of electro-optical arrangements (M. Tobias, International Handbook of Liquid Crystal Displays 1975-1976, Ovum Ltd., London 1976).
Moreover liquid crystals are usable with advantage as orienting medium in spectroscopy in the visible and near ultra-violet range, in nuclear resonance spectroscopy and in gas chromatography (G. Meier, E. Sackmann, J. G.
Grabmaier. "Applications of Liquid Crystals", Springer-Verlag, Berlin Heidelberg-New York 1975).
Hitherto the substituted benzoic acid phenyl esters were frequently used for the stated purposes (DDR WP 86,269; R. Steinstrasser, Z. Naturforsch. 27b 774 (1972)). These esters possess a relatively high viscosity which, especially at low temperatures, undesirably causes high switch-on and switch-off times in electrooptical components. In some cases the clarification points lie undesirably low or the melting points possess excessively high values.
The present invention comprises the use of new crystalline-liquid substances, which possess a high chemical and thermal stability, no inherent coloration in the visible spectral range, sufficiently high clarification points with sufficiently low melting points and low viscosity values, in electro-optical arrangements for the modulation of the transmitted or incident light and for the reproduction of digits, signs and images, also as orienting medium for spectroscopy and gas chromatography.
It has been found that nematic crystalline liquid substances of the general formulae
wherein R'=CnH2n,, with n=l to 9 R2=CNH2n+1-, CnH2n+1O-, CnH2n+1COO-,CnH2n+1OCOO-with n=1 to 9.
-CN, -Cl, -Br, -C2H4CN
R3=H,-CH3, -C2H5, -Cl, -Br, -CN, -CH2CN R4=CnH2n+1-or CnH2n+1O- with n=0 to 9 can be used in electro-optical arrangements for the modulation of the transmitted or incident light and for the reproduction of digits, signs and images, also as orienting medium for spectroscopy and gas chromatography. The substances possess high chemical and thermal stability, no inherent coloration in the visible spectral range, high clarification points with sufficiently low melting points and low viscosity values.
By the production of mixtures, especially eutectic mixtures the melting points are also greatly reduced and with clarification points little changed the working temperature ranges are also substantially increased. The conversion temperatures of substances according to the invention may be seen from the following Tables 1 to 3.
By the addition of dyestuffs in concentrations up to 5% the mixtures can be coloured and are then usable for electro-optical components on the basis of the guest-host effect.
TABLE 1
conversion No. R' R2 R3 f.p. sm-sm sm-nem Cl.p.
1 CH3- CH3O- H 107 - - 229 2 CM3- C4H9O- H 81 - - 197.5 3 CH3- C7H15O- H 81 - - 187 4 CH3- C8H17O- H 67 - - 170 5 CH3- C4H9- H 73 - - 159 6 C2H5- CH3- H 62 - - 188 7 C2H5- CH3O- H 80 - - 245 8 C2H5- C4H9- H 66 - - 180 9 C2H5- C7H15O- H 63 - - 184 10 C2H5- C8H17O- H 58 - - 175 11 C3H7- CH3O- H 94 - - 245 12 C3H7- C2H5O- H 112 - - 238 13 C3H7- C4H9O- H 75 - - 222 14 C3H7- C5H11O- H 67.5 - - 214 15 C3H7- C7H15O- H 75 - (70) 203 16 C3H7- CH3- H 72-73 - - 240 17 C3H7- C4H9- H 74-75 - 83 198 18 C4H9- CH3O- H 121 - - 236 19 C4H9- C2H5O- H 104 - - 231 20 C4H9- C4H9O- H 74-75 - 88 218 21 C4H9- C5H11O- H 71-72 - 110 206.5 22 C4H9- C7H15O- H 66-67 - 126 196 23 C4H9- CH3- H 78 - - 208 24 C4H9- C3H7- H 82 - 92 206 25 C4H9- C4H9- H 65 - 115 192 26 C5H11- CH3O- H 97-98 - (59) 237 27 C5H11- C2H5O- H 103 - - 236 28 C5H11- C4H9O- H 85 (70) 124 216 ( ) monotropic conversion Table 1 (Continued) conversion No. R' R2 R3 f.p. sm-sm sm-nem Cl.p.
29 C5H11- C7H15O- H 66 88 150 202 30 C5H11- CH3- H 56-57 - 90 215 31 C5H11- C3H7- H 78 - 121 209 32 C5H11- C4H9- H 78-79 - 136 195 33 C4H11- NC- H 98-99 - - 255 34 CH3- C7H15O- C2H5- 47.5 - - 88 35 C3H7- C7H15O- C2H5- 62-63 - - 123 36 C5H11- C7H15O- C2H5- 51-52 - - 120 37 C6H13- C7H15O- C2H5- 44-45 - - 116.5 38 CH3- C7H15O- Cl- 80 - - 142 39 C2H5- C4H9O- Cl- 78 - - 175 40 C2H5- C7H15O- Cl- 73 - - 151 41 C4H9- C4H9O- Cl- 77-78 - - 188 42 C3H7- C7H15O- Cl- 73 - - 174 43 C4H9- C7H15O- Cl- 73-74 - - 166 44 C5H11- C7H15O- Cl- 66-67 - - 154 ( ) monotropic conversion TABLE 2
No. R' R2 f.p. Cl.p.
45 C2H5- CH3- 92 142.5 46 C4H9- CH3- 88 179-180 47 C5H11- CH3- 76 185 48 CH3- H- 68-69 (48) 49 C3H7- C2H5- 47 130 50 C4H9- C2H5- 50-51 129 51 C5H11- C2H5- 42-43 133-134 52 C6H13- C2H5- 53 122 53 C3H7 Cl- 73 186 54 C4H9 Cl- 83 181 55 C5H11 Cl- 69-70 190 TABLE 3
Conversion No. R' R4 f.p. sm-nem Cl.p.
56 C4H9- C4H9- 68 - 161 57 C5H13- CH3- 60 - 105 58 C5H13- C5H11- 73 - 146 59 C2H5- C5H9O- 120 - 141 60 CH3O- C4H9- 110 - 212 61 C2H5O- C4H9- 108 - 212 62 C5H13O- H 125 218 255 63 C6H13O- CH3- 50 63 151 64 C5H13O- C4H9- 72 82 200 65 C5H13O- C4H9O- 66 173 183 66 CH3O- C4H9O- 110 - 145 67 C2H5O- C4H9O- 95 - 150 Examples of Preparation Example 1 The compounds with
are prepared by reaction of 4 - n - alkylcyclohexanoyl chlorides with the substituted 4 - hydroxybenzoic acid phenyl esters according to the formula
The reaction take splace in pyridine at room temperature, purification of the substances is achieved by repeated re-crystallisation out of methanol.
Example 2 The combinations with
are prepared by reaction of 4 - n - alkylcyclohexanoyl chlorides with the 2substituted hydroquinones according to the formula
The reaction takes plce in pyridine at room temperature, purification of the substances is achieved by repeated re-crystallisation out of methanol.
Example 3 Substance No. 51 displays the dynamic scatter effect in the usual electrooptical arrangements. At 50 Hz alternating-current voltage a threshold voltage of Us=7.5 V is found, with direct-current voltage at threshold voltage of Us=5.5 V. At voltages amounting to 2.5 times the value of U,, good contrasts of 20:1 or higher are achieved. Even on application of voltages up to 60 V, no decomposition phenomena of any kind are observed.
Example 4 Substance 57 possesses positive dielectric anisotropy and is suitable for electro-optical arrangements on the basis of the field effects (Freedericksz transposition, Schadt-Helfrich effect, Guest-Host effect). In a Schadt-Helfrich cell (twist cell) a threshold voltage of 4 V/50 Hz was found, the complete re-orientation was achieved at 8 V/50 Hz.
Example 5 1% methyl red was mixed into substance No. 57 and an oriented preparation was produced with horizontal stratum. On irradiation with polarised light the typical absorption band of methyl red is found, if the polarisation plane of the light is arranged parallel with the preferred direction of the nematic stratum. On the other hand no absorption can be substantiated if the plane of polarisation of the light is arranged perpendicularly to the preferred direction of the nematic stratum.
This substantiation of dichroism of the dyestuff methyl red is based upon the directed incorporation of the dyestuff molecules according to the orientation of the nematic matrix. Since the substances according to the invention display no absorption in the visible spectral zone, they can be used advantageously for spectroscopy in this zone. With the aid of electric fields (5 V/50 Hz) in electrooptical components the originally horizontal stratum is erected and thus a colour change from red to pale pink is achieved.
Compounds of the formula
may be obtained by analogous methods to those described above.
Summary Crystalline-liquid Substances Liquid crystals are suitable by reason of their electro-optical effects for the production of opto-electronic components, furthermore they can be used as orienting medium in spectroscopy and gas chromatography.
The purpose of the invention is the use of substances which are chemically and thermally stable and colourless and possess relatively high clarification points with sufficiently low melting points.
As crystalline-liquid substances there are used compounds of the general formula
wherein R1=CnH2n+1 with n=1 to 9 R2=CnH2n+1-, CnH2n+1O-, CnH2n+1COO-, CnH2n+1OCOO with n=1 to 9, -CN, -Cl, -Br, -C2H4CN
R3=H, -CH3, -C2H5, -Cl, -Br, -CN, -CH2CN R4=CnH2n+1, CnH2n+1O with n=0 to 9 Further crystalline-liquid or non-crystalline liquid substances, especially dyestuffs, can advantageously be added to the substances according to the invention.
WHAT WE CLAIM IS: 1. Crystalline-liquid substances of the general formula
wherein R1=CnH2n+1 with n=1 to 9 R2=CnH2n+1-, CnH2n+1O-, CnH2n+1COO-, CnH2n+1OCOO-, with n=1 to 9, -CN, -C1, -Br, -C2H4CN
R3=H, -CH3, -C2H9, -Cl, -Br, -CN, -CH2CN R4=CnH2n+1-, CnH2n+1O- with n=0 to 9.
2. Crystalline-liquid substances according to Claim 1, char5acterised in that
**WARNING** end of DESC field may overlap start of CLMS **.

Claims (5)

**WARNING** start of CLMS field may overlap end of DESC **. Compounds of the formula may be obtained by analogous methods to those described above. Summary Crystalline-liquid Substances Liquid crystals are suitable by reason of their electro-optical effects for the production of opto-electronic components, furthermore they can be used as orienting medium in spectroscopy and gas chromatography. The purpose of the invention is the use of substances which are chemically and thermally stable and colourless and possess relatively high clarification points with sufficiently low melting points. As crystalline-liquid substances there are used compounds of the general formula wherein R1=CnH2n+1 with n=1 to 9 R2=CnH2n+1-, CnH2n+1O-, CnH2n+1COO-, CnH2n+1OCOO with n=1 to 9, -CN, -Cl, -Br, -C2H4CN R3=H, -CH3, -C2H5, -Cl, -Br, -CN, -CH2CN R4=CnH2n+1, CnH2n+1O with n=0 to 9 Further crystalline-liquid or non-crystalline liquid substances, especially dyestuffs, can advantageously be added to the substances according to the invention. WHAT WE CLAIM IS:
1. Crystalline-liquid substances of the general formula
wherein R1=CnH2n+1 with n=1 to 9 R2=CnH2n+1-, CnH2n+1O-, CnH2n+1COO-, CnH2n+1OCOO-, with n=1 to 9, -CN, -C1, -Br, -C2H4CN
R3=H, -CH3, -C2H9, -Cl, -Br, -CN, -CH2CN R4=CnH2n+1-, CnH2n+1O- with n=0 to 9.
2. Crystalline-liquid substances according to Claim 1, char5acterised in that
further crystalline-liquid or non-crystalline liquid substances are mixed into the substances of the general formula
3. A crystalline-liquid substance as claimed in Claim 2 wherein said further substance is a dyestuff.
4. Crystalline-liquid substances as claimed in Claim 1, substantially as hereinbefore described.
5. Crystalline-liquid substances, substantially as described in any one of the examples.
GB35278A 1977-02-11 1978-01-05 Aromatic dicarboxylic esters useful as liquid crystal substances Expired GB1596011A (en)

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DD19733177A DD138473A3 (en) 1977-02-11 1977-02-11 CRYSTALLINE-LIQUID SUBSTANCES

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CH (1) CH639064A5 (en)
DD (1) DD138473A3 (en)
DE (1) DE2752975C2 (en)
GB (1) GB1596011A (en)
SU (1) SU920062A1 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2508480A1 (en) * 1981-06-25 1982-12-31 Werk Fernsehelektronik Veb NEMATIC LIQUID CRYSTALS AND PROCESS FOR THEIR MANUFACTURE
US4723005A (en) * 1983-09-10 1988-02-02 Merck Patent Gesellschaft Mit Beschrankter Haftung Anisotropic compounds and liquid crystal mixtures
US5252252A (en) * 1983-09-10 1993-10-12 Merck Patent Gesellschaft Mit Beschraenkter Haftung Anisotropic compounds and liquid crystal mixtures

Families Citing this family (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4113647A (en) * 1976-08-13 1978-09-12 The Secretary Of State For Defence In Her Britannic Majesty's Government Of The United Kingdom Of Great Britain And Northern Ireland Liquid crystalline materials
JPS5483694A (en) * 1977-12-16 1979-07-03 Hitachi Ltd Nematic liquid crystal body for display device
DE2800553A1 (en) * 1978-01-07 1979-07-12 Merck Patent Gmbh CYCLOHEXAN DERIVATIVES
JPS5941983B2 (en) * 1978-02-17 1984-10-11 大日本インキ化学工業株式会社 trans(equatorial↓-equatorial)1,4↓-disubstituted cyclohexane derivative
FR2419966A1 (en) * 1978-03-17 1979-10-12 Thomson Csf DIESTER TYPE LIQUID CRYSTAL WITH A SMECTIC PHASE, AT LOW DIELECTRIC ISOTROPY FREQUENCY, AND DISPLAY DEVICE USING THIS CRYSTAL
US4293434A (en) * 1978-08-08 1981-10-06 VEB Werk fur Fernsehelektronik Berlin im VEB Kombinat Mikroelektronik Liquid crystal compounds
US4279770A (en) * 1978-09-20 1981-07-21 Chisso Corporation Liquid crystal 2,3-dicyano-hydroquinone derivatives
EP0019665B2 (en) * 1979-05-28 1987-12-16 MERCK PATENT GmbH Liquid-crystal compositions
DE2933563A1 (en) * 1979-07-18 1981-02-05 Bbc Brown Boveri & Cie ANISOTROPE CONNECTIONS WITH NEGATIVE DK ANISOTROPY
US4328116A (en) * 1979-11-01 1982-05-04 Minnesota Mining And Manufacturing Company Liquid crystal compositions for multiplexed displays
US4309304A (en) * 1979-11-01 1982-01-05 Exxon Research & Engineering Co. Liquid crystal compositions for multiplexed displays
US4290905A (en) * 1979-12-26 1981-09-22 Kabushiki Kaisha Suwa Seikosha Ester compound
JPS572385A (en) * 1980-06-06 1982-01-07 Hitachi Ltd Liquid crystal composition
CH647230A5 (en) * 1981-06-18 1985-01-15 Hoffmann La Roche Phenyl esters, and the use thereof as components of liquid-crystalline mixtures
CH666259A5 (en) * 1984-11-14 1988-07-15 Nii Prikladnych FLUESSIGKRISTALLINE 4-N-pentylphenyl 4 '- (trans-4' '- N-alkylcyclohex-2-enoyloxy) benzoic acids.
EP0247466B1 (en) * 1986-05-22 1993-11-24 F. Hoffmann-La Roche Ag Liquid-crystal derivatives of phenyl benzoate
US5082589A (en) * 1986-05-22 1992-01-21 Hoffmann-La Roche Inc. Liquid crystalline esters
US5648021A (en) * 1994-01-17 1997-07-15 Hoechst Aktiengesellschaft Phenanthrene derivatives and their use in liquid-crystalline mixtures
DE4423098A1 (en) 1994-07-01 1996-01-04 Hoechst Ag Use of conjugated compounds containing pyrimidine groups as electroluminescent materials
KR101677764B1 (en) * 2009-04-21 2016-11-18 스미또모 가가꾸 가부시끼가이샤 Compound

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2508480A1 (en) * 1981-06-25 1982-12-31 Werk Fernsehelektronik Veb NEMATIC LIQUID CRYSTALS AND PROCESS FOR THEIR MANUFACTURE
US4723005A (en) * 1983-09-10 1988-02-02 Merck Patent Gesellschaft Mit Beschrankter Haftung Anisotropic compounds and liquid crystal mixtures
US5252252A (en) * 1983-09-10 1993-10-12 Merck Patent Gesellschaft Mit Beschraenkter Haftung Anisotropic compounds and liquid crystal mixtures

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Publication number Publication date
DE2752975A1 (en) 1978-08-17
DD138473A3 (en) 1979-11-07
JPS6160113B2 (en) 1986-12-19
JPS53113284A (en) 1978-10-03
DE2752975C2 (en) 1985-07-18
SU920062A1 (en) 1982-04-15
CH639064A5 (en) 1983-10-31

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Effective date: 19980104