CA1189235A - Process for production of phenolic resin - Google Patents
Process for production of phenolic resinInfo
- Publication number
- CA1189235A CA1189235A CA000370858A CA370858A CA1189235A CA 1189235 A CA1189235 A CA 1189235A CA 000370858 A CA000370858 A CA 000370858A CA 370858 A CA370858 A CA 370858A CA 1189235 A CA1189235 A CA 1189235A
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- Prior art keywords
- phenol
- resin
- weight
- phenolic resin
- parts
- 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.)
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Abstract
Title of the Invention PROCESS FOR PRODUCTION OF PHENOLIC RESIN
Abstract of the Disclosure A process for producing a phenolic resin compris-ing condensing a phenol component and an aldehyde component, characterized in that the phenol component comprises (high-molecular-weight phenolic compounds which are left after bisphenol A-containing by-products formed in the production of bisphenol A by condensing acetone and phenol in the presence of an acid catalyst are treated at a high temper-ature of at least 150°C in the presence of an alkaline catalyst to remove low-boiling components therefrom.
Abstract of the Disclosure A process for producing a phenolic resin compris-ing condensing a phenol component and an aldehyde component, characterized in that the phenol component comprises (high-molecular-weight phenolic compounds which are left after bisphenol A-containing by-products formed in the production of bisphenol A by condensing acetone and phenol in the presence of an acid catalyst are treated at a high temper-ature of at least 150°C in the presence of an alkaline catalyst to remove low-boiling components therefrom.
Description
2~5 This invention relates to new process for producing phenolic resin by using as phenol component phenolic compounds obtained as by-products in the produc-tion ox bisphenol A.
Phenolic resins include novolaks ob-t~ined by condensing a phenol component such as phenol and/or cresol and an aldehyde component such as ormaldehyde in the presence of an acid catalyst, and resols obtained by condensing -the above two components in the presence of an alkaline catalys-t, They find extensive use a molded articles or as binders or the production of foundry molds, abrasives, brakes laminates 9 etc.
Co~entional phenolic resins ob-tained by uæing phenol and/or cresol as a phenol componen-t, however9 do not completely meet all of -the requirements in various uses. For example molded articles prepared from -these phenolic res.ins generally have poor flexural s-treng-th, and when such a phenolic resin is usecl as a binder for foundry molds9 cracking ox the molds tends to occur, It is an object o:~ this in~en-tion therefore to provide a new process or producing a phenolic resin free ~'rom the aforesaid defects o:E the conven-tional phenolic resins.
According to this inventiong there is provided a process or producing a phenolic resin, charac-teri~ed by using as a phenol component high-molecular-weight phenolic compounds which are let after bisphenol A contalning byproducts formed in the production ox bisphenol A by condensing acetone and phenol in the presence ox an acid I
~8g~35 catalyst are treated at a temperature of at least 150C
in the presence of an alkaline catalyst to remove low-boiling components therefrom.
The high-molecular-weight phenolic compounds used as the phenol component in the process of this invention are products which remain after the by-product residue formed in the production of bisphenol A is treated at a high temperature in the presence of an alkaline catalyst to cleave it and distill off the resulting isopropenyl phenol and phenol. More specifically these compounds are obtained by the following procedure Bisphenol A is produced by dehydrocondensing phenol and acetone in the presence of an acid catalyst such as hydrochloric acid, sulfuric acid, p-toluenesulfonic acid or an acidic ion exchange resin, When bisphenol is separated from the reaction mixture by a usual procedure such as distillation or recrystallization from an organic solvent or water, there is left a residue containing dihydroxydiphenylpropane isomers a chromane compound called chromane I, other polyphenol compounds and a small amount of bisphenol A (to be referred -to as a residue.
When the residue is treated at a high temperature of at least 150C, preferably 180 to 250C, under a reduced pressure of not more than lO0 mmTlg, the hydroxydiphenyl propane in the residue undergoes cleavage reaction to Porm phenol and isopropenyl phenol. These cleavage products distill off from the reaction mixture and black tarry high-molecular-weight phenolic compounds remain.
- In the process of this invention, a phenolic resin is produced by using these high-molecular-weight phenolic compounds as a phenol component.
Preferably phenol is used in combination with the high-molecular-weight phenolic compounds as the phenol component in producing a phenolic resin by the process of -the inven-tion. In this case -the amount ox phenol is usually 20 to 90~ by weight based on the to-tal weight ox the phenol and the high-molecular-weight phenolic compounds 9 Sultable ca-talysts used in the condensation reaction ox the phenol component wi-th formaldehyde in the invention are acid catalys-ts such as hydrochloric acid, sulfuric acid and oxalic acidJ The amoun-t ox the acid catalyst is preferably in the range ox 0.01 to 2 parts by weight per 100 parts by weight of the phenol component, c the high-molecular-weight phenolic compounds or a mixture ox these with phenol, as in the produc-tion oE
ordinary phenolic resins.
The other conditions in -the condensa-tion react:ion can be set according to usual manuacturing conclitions Eor phenolic resins. specifically, the proportion ox formalde-hyde used is 0.5 -to 1.5 moles per mole of the phenol component. The reaction temperature is usually 50 to 100C, and the reaction time is 1 to 15 hours 9 usually 2 -to 6 hours.
It required the catalyst is neutralized a:Eter -the condensation reaction, and subsequently the reaction mixture is dehydra-ted and the unreac-ted phenol removedO
Thus, a novolak-type phenolic resin is ob-tained, 2~i The phenolic resin obtained by the process of the invention can be used in the same applications by the same methods as conventional phenolic resins, For example when it is to be used as a molding material, the phenolic resin is mixed wi-th hexamethylenetetramine 9 a filler, etc, and the mixture is cured under heat and pressure to Norm a molded article. The resulting molded article is characterized by having improved flexural strength over a molded ar-ticle prepared from a conventional phenolic resinO
Fur-thermore, it is noted in-terestingly -that in injec-tion molding, the phenolic resin in accordance with this invention shows greatly improved heat stability within the cylinder of the injection molding machine.
For the production of a foundry mold the phenolic resin obtained by this inven-tion is used as a binder and is mixed with required materials including sand particles, hexamethylenete-tramine and a lubrican-t, and the resulting resin coated sand is heated in a mold.
The foundry mold thus obtained has higher flex~lral s-treng-th and crack resistance than -that obtained by using an ordinary phenolic resin as a binder.
The phenolic resin in accordance with this invention may be used as a binder or glass fibers, paper9 etcO, as well FurthermoreJ a foamed phenolic resin may be prepared from it The phenolic resin of the invention has a slower speed ox curing than conventional onesp and -this is presumably one of the causes of i-ts increased stability within the cylinder of an injection molding machine during l~B9235 injection molding. If desired, its curing speed may be increased by adding a curing accelerater such as an alkaline earth metal oxide or hydroxide or various organic acids, The following examples illustrate the process of -this invention more specifically. All parts and percentages in these examples are by weight.
A Production of phenolic resins Resin I
__ A reactor was charged with 700 parts of phenol 300 parts of high-molecular-weight phenolic compounds, 450 parts of a 37/~ aqueous solution of formaldehyde and 7,5 parts of oxalic acid, and with stirring, -they were heated In 35 minutes, refluxin~ began IJnder reflux, the reaction was further carried out for 90 minutes.
After the reaction, dehydra-tion and the removal of the unreacted phenol were performed in a customary manner to afford 965 parts of a resin having a sof-tening poin-t of 93C.
Res The procedure of producing the resin I was repeated except that 500 parts of phenol, 500 parts of the high-molecular-weight phenolic compounds and 371 parts of a 37 aqueous solution of formaldehyde were charged. There was obtained 883 parts of a resin having a softening point of 105.5C
Resin III
-- The procedure of producing the resin I was ;23~i repeated except that 300 parts of phenol, 700 parts of the high-molecular-weight phenolic compounds and 239 parts of a 37 aqueous solution ox formaldehyde were charged, There was obtained 979 parts of a resin having a softening point of 109,5C, D~gg~
A reactor equipped with a stirrer, a reflux condenser and a thermome-ter was charged wi-th 1000 parts of phenol and 692 par-ts of a 37 aqueous solution of formaldehyde and 4,5 parts of 20 hydrochloric acidg and -they were heated with stirring. At about 97C, refluxing began, Ater -the start of reflying 9 -the reaction was further performed or 60 minutes under re~lux. After the reaction, dehyclration and the removal of the unreacted phenol were performed in a customary manner to afford 1050 parts of phenol novolak having a softening point of 100C, B, Production of resin-coated sand.
To each of the phenolic resins ob-tained by the procedures set forth in above was added 15,~ by weight, based on the phenolic resin, of hexamethylene-tetramine.
Three parts ox -the resulting powder was d.issolved in
Phenolic resins include novolaks ob-t~ined by condensing a phenol component such as phenol and/or cresol and an aldehyde component such as ormaldehyde in the presence of an acid catalyst, and resols obtained by condensing -the above two components in the presence of an alkaline catalys-t, They find extensive use a molded articles or as binders or the production of foundry molds, abrasives, brakes laminates 9 etc.
Co~entional phenolic resins ob-tained by uæing phenol and/or cresol as a phenol componen-t, however9 do not completely meet all of -the requirements in various uses. For example molded articles prepared from -these phenolic res.ins generally have poor flexural s-treng-th, and when such a phenolic resin is usecl as a binder for foundry molds9 cracking ox the molds tends to occur, It is an object o:~ this in~en-tion therefore to provide a new process or producing a phenolic resin free ~'rom the aforesaid defects o:E the conven-tional phenolic resins.
According to this inventiong there is provided a process or producing a phenolic resin, charac-teri~ed by using as a phenol component high-molecular-weight phenolic compounds which are let after bisphenol A contalning byproducts formed in the production ox bisphenol A by condensing acetone and phenol in the presence ox an acid I
~8g~35 catalyst are treated at a temperature of at least 150C
in the presence of an alkaline catalyst to remove low-boiling components therefrom.
The high-molecular-weight phenolic compounds used as the phenol component in the process of this invention are products which remain after the by-product residue formed in the production of bisphenol A is treated at a high temperature in the presence of an alkaline catalyst to cleave it and distill off the resulting isopropenyl phenol and phenol. More specifically these compounds are obtained by the following procedure Bisphenol A is produced by dehydrocondensing phenol and acetone in the presence of an acid catalyst such as hydrochloric acid, sulfuric acid, p-toluenesulfonic acid or an acidic ion exchange resin, When bisphenol is separated from the reaction mixture by a usual procedure such as distillation or recrystallization from an organic solvent or water, there is left a residue containing dihydroxydiphenylpropane isomers a chromane compound called chromane I, other polyphenol compounds and a small amount of bisphenol A (to be referred -to as a residue.
When the residue is treated at a high temperature of at least 150C, preferably 180 to 250C, under a reduced pressure of not more than lO0 mmTlg, the hydroxydiphenyl propane in the residue undergoes cleavage reaction to Porm phenol and isopropenyl phenol. These cleavage products distill off from the reaction mixture and black tarry high-molecular-weight phenolic compounds remain.
- In the process of this invention, a phenolic resin is produced by using these high-molecular-weight phenolic compounds as a phenol component.
Preferably phenol is used in combination with the high-molecular-weight phenolic compounds as the phenol component in producing a phenolic resin by the process of -the inven-tion. In this case -the amount ox phenol is usually 20 to 90~ by weight based on the to-tal weight ox the phenol and the high-molecular-weight phenolic compounds 9 Sultable ca-talysts used in the condensation reaction ox the phenol component wi-th formaldehyde in the invention are acid catalys-ts such as hydrochloric acid, sulfuric acid and oxalic acidJ The amoun-t ox the acid catalyst is preferably in the range ox 0.01 to 2 parts by weight per 100 parts by weight of the phenol component, c the high-molecular-weight phenolic compounds or a mixture ox these with phenol, as in the produc-tion oE
ordinary phenolic resins.
The other conditions in -the condensa-tion react:ion can be set according to usual manuacturing conclitions Eor phenolic resins. specifically, the proportion ox formalde-hyde used is 0.5 -to 1.5 moles per mole of the phenol component. The reaction temperature is usually 50 to 100C, and the reaction time is 1 to 15 hours 9 usually 2 -to 6 hours.
It required the catalyst is neutralized a:Eter -the condensation reaction, and subsequently the reaction mixture is dehydra-ted and the unreac-ted phenol removedO
Thus, a novolak-type phenolic resin is ob-tained, 2~i The phenolic resin obtained by the process of the invention can be used in the same applications by the same methods as conventional phenolic resins, For example when it is to be used as a molding material, the phenolic resin is mixed wi-th hexamethylenetetramine 9 a filler, etc, and the mixture is cured under heat and pressure to Norm a molded article. The resulting molded article is characterized by having improved flexural strength over a molded ar-ticle prepared from a conventional phenolic resinO
Fur-thermore, it is noted in-terestingly -that in injec-tion molding, the phenolic resin in accordance with this invention shows greatly improved heat stability within the cylinder of the injection molding machine.
For the production of a foundry mold the phenolic resin obtained by this inven-tion is used as a binder and is mixed with required materials including sand particles, hexamethylenete-tramine and a lubrican-t, and the resulting resin coated sand is heated in a mold.
The foundry mold thus obtained has higher flex~lral s-treng-th and crack resistance than -that obtained by using an ordinary phenolic resin as a binder.
The phenolic resin in accordance with this invention may be used as a binder or glass fibers, paper9 etcO, as well FurthermoreJ a foamed phenolic resin may be prepared from it The phenolic resin of the invention has a slower speed ox curing than conventional onesp and -this is presumably one of the causes of i-ts increased stability within the cylinder of an injection molding machine during l~B9235 injection molding. If desired, its curing speed may be increased by adding a curing accelerater such as an alkaline earth metal oxide or hydroxide or various organic acids, The following examples illustrate the process of -this invention more specifically. All parts and percentages in these examples are by weight.
A Production of phenolic resins Resin I
__ A reactor was charged with 700 parts of phenol 300 parts of high-molecular-weight phenolic compounds, 450 parts of a 37/~ aqueous solution of formaldehyde and 7,5 parts of oxalic acid, and with stirring, -they were heated In 35 minutes, refluxin~ began IJnder reflux, the reaction was further carried out for 90 minutes.
After the reaction, dehydra-tion and the removal of the unreacted phenol were performed in a customary manner to afford 965 parts of a resin having a sof-tening poin-t of 93C.
Res The procedure of producing the resin I was repeated except that 500 parts of phenol, 500 parts of the high-molecular-weight phenolic compounds and 371 parts of a 37 aqueous solution of formaldehyde were charged. There was obtained 883 parts of a resin having a softening point of 105.5C
Resin III
-- The procedure of producing the resin I was ;23~i repeated except that 300 parts of phenol, 700 parts of the high-molecular-weight phenolic compounds and 239 parts of a 37 aqueous solution ox formaldehyde were charged, There was obtained 979 parts of a resin having a softening point of 109,5C, D~gg~
A reactor equipped with a stirrer, a reflux condenser and a thermome-ter was charged wi-th 1000 parts of phenol and 692 par-ts of a 37 aqueous solution of formaldehyde and 4,5 parts of 20 hydrochloric acidg and -they were heated with stirring. At about 97C, refluxing began, Ater -the start of reflying 9 -the reaction was further performed or 60 minutes under re~lux. After the reaction, dehyclration and the removal of the unreacted phenol were performed in a customary manner to afford 1050 parts of phenol novolak having a softening point of 100C, B, Production of resin-coated sand.
To each of the phenolic resins ob-tained by the procedures set forth in above was added 15,~ by weight, based on the phenolic resin, of hexamethylene-tetramine.
Three parts ox -the resulting powder was d.issolved in
3 parts of a mixture of -toluene and methanol (l:l by weight). The solution was added to 100 parts of sand (flattery sand) and they were kneaded. Fur-thermore 7 O.
part of calcium stearate was added, and the mixture was kneaded to afford a resin-coated sand. the resin-coated sand was put into a mold and heated at 250C for 60 seconds to form a shell foundry mold ~8g23~
The properties of -the resulting foundry molds are shown in table 1, Table 1 _ _ . , _ _ .
Resin I II III IY
(comparison) I______ , .
Shell bending strength at room 42 7 37.2 39.3 34.4 temperature (kgf/cm2 ) (*1 ) _ . I__ __ __ .
Coefficient of 0 81 0 68 0.47 1.25 expansion (,~) (*2) .
. _ _ _ .
*l)o Tested in accordance with JIS (Japanese Industrial Standards) K-6910.
(~2)~ Tested in accordance with JOT (Japanese association of Casting Technology) test me-thod SM-7. cylin-drical test specimen is heated to 1200C, and the amount of its linear expansion in the direction of its height is measured and expressed in percen-tage based on the original size.
(*I ested in accordance with JACT -testing method 'M-9.
The longer the crack -test time, the better -the crack resistance of the specimen.
It is seen from the results shown in Table 1 that the resins in accordance wi-th this invention contri-bute to improved ~lexural strength in foundry molds produced by using them as a binder, and because of this low coefficient of expansion, the foundry molds produced - have very good resistance to cracking, 3~i Production of a phenolic resin Resin V
Phenol (400 parts), 100 parts of a high-molecular-weigh-t phenolic compound, 280 par-ts of a 37 aqueous solution of formaldehyde and 0.4 part of 20 hydrochloric acid were mixed, and hea-ted with stirring. In 30 minu-tes aster the startlng o:E refluxing, 2~0 par-ts of 20 hydro-chloric acid was added anrl the reac-tion was performed for ~0 minu-tes. After -the reaction 9 dehydration and -the removal of the unreacted phenol were performed in a customary manner -to afford 505 parts of a phenolic resin having a sof-tening point of 98C.
B. Production of a phenolic resin molded ar-ticle One hundred parts of -the resin or, 0.4 part of salicyclic acid, 13 parts of hexame-thylene~tetramine, 1 part of calcium steara-te and 100 par-ts of wood powder were kneaded by a roll at an elevated temperature. The kneaded mixture was injec-ted into a mold a-t 180C by an injection molding machine, and cured a-t -the same -tempera-ture for 90 seconds.
The properties of the resul-tin~ molded ar-ticle are shown in Table 2 in comparison wi-th those of a molcled article prepared from resin IV (comparison).
\
g Table 2 X esln I,, (comparison) I_ Flexural streng-th (kgf/mm2) l 9~6 9.0 _~ . . , . ,. .
~harpy impact strength (kgf.cm/cm2) (*2) 2.6 2.3 .~ , argot hardness (*3) 56 62 I_.____ ................ . ,, . .
R~i1 sro tin condo/ _ _ *l)o Measured in accordance with JIS K~6911.
(*2). Measured in accordance with JIS K-6911.
(*3)O Measured 60 seconds after wi-thdrawal from -the mold by a Barcol Impressor (Model GYZJ-934-1, a product of Barber Colman Company).
ho A molding rna-terial is injected after it has been caused to reside in -the cylinder of an injection molding machine for a prede-termined period of time and the limit of the resiclence time which causes a failure of injection is determined, The longer the residence timel -the more thermally stable -the molding mater:ial.
It is seen from the results shown in Table 2 that -the resin in accordance with -this invention gives a molded ar-ticle of improved flexural strength and the heat s-tability of the resin in the cylinder of -the injection molding machine is excellent.
-
part of calcium stearate was added, and the mixture was kneaded to afford a resin-coated sand. the resin-coated sand was put into a mold and heated at 250C for 60 seconds to form a shell foundry mold ~8g23~
The properties of -the resulting foundry molds are shown in table 1, Table 1 _ _ . , _ _ .
Resin I II III IY
(comparison) I______ , .
Shell bending strength at room 42 7 37.2 39.3 34.4 temperature (kgf/cm2 ) (*1 ) _ . I__ __ __ .
Coefficient of 0 81 0 68 0.47 1.25 expansion (,~) (*2) .
. _ _ _ .
*l)o Tested in accordance with JIS (Japanese Industrial Standards) K-6910.
(~2)~ Tested in accordance with JOT (Japanese association of Casting Technology) test me-thod SM-7. cylin-drical test specimen is heated to 1200C, and the amount of its linear expansion in the direction of its height is measured and expressed in percen-tage based on the original size.
(*I ested in accordance with JACT -testing method 'M-9.
The longer the crack -test time, the better -the crack resistance of the specimen.
It is seen from the results shown in Table 1 that the resins in accordance wi-th this invention contri-bute to improved ~lexural strength in foundry molds produced by using them as a binder, and because of this low coefficient of expansion, the foundry molds produced - have very good resistance to cracking, 3~i Production of a phenolic resin Resin V
Phenol (400 parts), 100 parts of a high-molecular-weigh-t phenolic compound, 280 par-ts of a 37 aqueous solution of formaldehyde and 0.4 part of 20 hydrochloric acid were mixed, and hea-ted with stirring. In 30 minu-tes aster the startlng o:E refluxing, 2~0 par-ts of 20 hydro-chloric acid was added anrl the reac-tion was performed for ~0 minu-tes. After -the reaction 9 dehydration and -the removal of the unreacted phenol were performed in a customary manner -to afford 505 parts of a phenolic resin having a sof-tening point of 98C.
B. Production of a phenolic resin molded ar-ticle One hundred parts of -the resin or, 0.4 part of salicyclic acid, 13 parts of hexame-thylene~tetramine, 1 part of calcium steara-te and 100 par-ts of wood powder were kneaded by a roll at an elevated temperature. The kneaded mixture was injec-ted into a mold a-t 180C by an injection molding machine, and cured a-t -the same -tempera-ture for 90 seconds.
The properties of the resul-tin~ molded ar-ticle are shown in Table 2 in comparison wi-th those of a molcled article prepared from resin IV (comparison).
\
g Table 2 X esln I,, (comparison) I_ Flexural streng-th (kgf/mm2) l 9~6 9.0 _~ . . , . ,. .
~harpy impact strength (kgf.cm/cm2) (*2) 2.6 2.3 .~ , argot hardness (*3) 56 62 I_.____ ................ . ,, . .
R~i1 sro tin condo/ _ _ *l)o Measured in accordance with JIS K~6911.
(*2). Measured in accordance with JIS K-6911.
(*3)O Measured 60 seconds after wi-thdrawal from -the mold by a Barcol Impressor (Model GYZJ-934-1, a product of Barber Colman Company).
ho A molding rna-terial is injected after it has been caused to reside in -the cylinder of an injection molding machine for a prede-termined period of time and the limit of the resiclence time which causes a failure of injection is determined, The longer the residence timel -the more thermally stable -the molding mater:ial.
It is seen from the results shown in Table 2 that -the resin in accordance with -this invention gives a molded ar-ticle of improved flexural strength and the heat s-tability of the resin in the cylinder of -the injection molding machine is excellent.
-
Claims (3)
1. In a process for producing a phenolic resin which comprises condensing a phenol component and an aldehyde component; the improvement wherein the phenol component comprises high-molecular-weight phenolic compounds which are left after bisphenol A-containing by-products formed in the production of bisphenol A by condensing acetone and phenol in the presence of an acid catalyst are treated at a temperature of at least 150°C
in the presence of an alkaline catalyst to remove low-boiling components therefrom.
in the presence of an alkaline catalyst to remove low-boiling components therefrom.
2. The process of claim 1 wherein the phenol compo-nent is a mixture of said high-molecular-weight phenolic compounds with phenol.
3. The process of claim 2 wherein the mixture is composed of 80 to 10% by weight of the high-molecular-weight phenolic compounds and 20 to 90% by weight of phenol.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000370858A CA1189235A (en) | 1981-02-13 | 1981-02-13 | Process for production of phenolic resin |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000370858A CA1189235A (en) | 1981-02-13 | 1981-02-13 | Process for production of phenolic resin |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1189235A true CA1189235A (en) | 1985-06-18 |
Family
ID=4119194
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000370858A Expired CA1189235A (en) | 1981-02-13 | 1981-02-13 | Process for production of phenolic resin |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1189235A (en) |
-
1981
- 1981-02-13 CA CA000370858A patent/CA1189235A/en not_active Expired
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