CA1320022C - Patterned metal plate and production thereof - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE

An uneven patterned metal strip or plate is formed with an uneven pattern as a surface decorative pattern. The pattern is constituted of one or more pattern unit containing a plurality of uneven dots. Each of the uneven dots has a size D. The uneven dots are arranged in a predetermined density to have given ration ? of occupying area versus plane area in said pattern unit. The size D and area ration ? being in a range of:
10 ? D ? 300 (µm) 30 ? ? ? 100 (%) and the size of said pattern unit has minimum length of 1 mm.

Description

:`- 132~2~

The present invention relates generally to a metal plate, such as steel plate, with a surface decorative pattern. More specifically, the invention relates to a patterned metal plate having dulled decorative pat-tern on its surface. The invention also relates to a method for producing the patterned metal plate. The invention particularly relates to a method for producing a decoratively patterned, corrosion resistant and weather resistant metal strip.
Because of cool appearance, plated metal plates, such as tin plate, chromium plating, galvanized plate and so forth, are rarely used in a form exposing the bear surface thereof. In order to make the metal plate use$ul, it is usual to print or paint the desired pattern on a surface of the metal plate. This requires a printing or a painting process increasing thereby the production cost.
In another approach to obtain metal plates of higher commercial values, metal plates with an emboss-treated surface have been propose~d. Uneven emboss pattern is formed on the metal plate surface for providing cube effect, natural feeling and shade Eor giving better guality feeling~ Nowadays, thxee types of emboss patterned metal plates have been developed and proposed.
For ~xample, the Japanese Patent First (unexamined) Publication (Tokkai) Showa 51-73576 and the Japanese Patent First (unexamined) Publication (Tokkai) Showa 53-88080 disclose a metal plates, on which surfaces are treated by metallic plating. On the metallic plating layer, an emboss patterned transparent _. ~n .~

' :

~32~2~

~ayer i~ forme~t In the ~lt~rn~ e, the m~talli~
plated ~ur-~ace i~ coate~ by a transparent layert ~t~o~
treatment is perf ormed ~or the ~r~t~p~rent layer . ~uch me~al plrtteS are provi~ed c~rroslon r~ t~ e and rU3~t-proo~in~ ability by th~ ~r5n~p~re~t l~yer ~d bri~h-t ~r c:10~8y appearGtJlCe.
Though s~lch pruce~s m~ty proYlde s~ f ~torll~F
high quAl ity o~ m~l plate with decora~iYe une~ren pattern, ~he pxodu~!tion pr~e~s require~ ~o v~riou~3 ex ra 3~ep~ . Thi~ ~or~lers thf~ proce~i~ t~ ~e ~ppl led for m~ proauc~ion an~ C~ es hlgh produc~i~n cost.
On ~he o~her hctn~, ~he ~tp~tne~e ~ertt ~?ir~
~unexamined~ ~uhl ic~ti~n (Tokkai) Shsw~ 3~4~4 propo~e~ to pr~vide embo~ pAtt~rn on the ~urface of th~
lS ' met~l pla~e. on which ~ur~ce met~llic ~ in~ or re~iJI
coa~i~g layer is ~o~med by rolling utili2ing ~ roll, on whi~h ~ur~ce embv~s ~re~men~; in ~ de~ir~ pattern i~;
~orme~. The met~l pl~t~ 1~ thug ~rmed urJever~ eml~Q
pei~t~ern c~rreæponding to the em~o~ pa~e~n o~ ~h~
~zo per lphe~ ur~ace of the roll e ~he metal pl~te th~ls produc~ ~na~ h~ve ~ube e~ecl~. TOkkai ~ho~ S4S4 further ~ropo#~ to ~r~vlde top to ~o~tom hel~h~
dlf:~r~n~ in ~he projecting p~rtion and depr~ed po~tlon within a ran~e .o~ ~ O ,Lm ~o ~00 ~Im ~nd ~ur~c~
~; rou~hne~ reater thsn or e:~u~l ~o ~ ~. By ~on~oll ~ r~g Y~uch ~ontrolled ma~nitude vf r~ughne~ on ~he ~u~fhcel th~ m~l plat4 i3ur~ce may ~e provid~d d~init~ p~ttern w i~h ~bnt ~ ~9~ 1n br ightn~
In thl~ process. ~inc~ ~he pl~ed l~yer ~n~
3c~ Sur~ e ~oa~in~ l~yer aEa ~ubi~t~rlg ~h~ lin~ pro~e~
ten~ ~C) exp~.nd to~e~her wi~h ~he met~1 pl~te ~o cau~e Crackin~ ~r}d pin ho}e ~o de~rade c~rrosion ~e~lst~ance and ru~t~proof ing abil ity . ~ur~h~rm~re, when ~h~ m~tal plate 1~ thin. the embo~e~l uneven p~t~Xn m~r be forlned 3~; With ~orming un~veness on t;he opposi~e ~ur~ . Thi~
n~r row~ khe us~ge .

... ... _ ......... _ _ _ _,,, , _ _ .... ~

- ~ ~320~22 The ~p~l~es~ P~tent: Fir~ (unex~mined~
Pu}~ a~ion ~okk~ h~w~ $1~ dis~lo~e a me.~l pl~l~e, be~r $urf~ce oP which i~ em~s tre~ted to ~orm ~n uneVeI} p~ttern~ 0~ the ~m~o~s ~re~:~ed ~ur~
surface p~otec.iv~ l~yer i~ fo~med~
Thl~ m~thod L~ ~ner~lly 2ppl i~a~ r forming r~r~dom uneven p~ern 2nd is diff ~ul~ ~o ~orm the de~ired uneven pa~ rrl. In th~ altern~tive~ in or~er to -Eorm the de~ir~d une~en p~t~ern~ lt i~
ta e6~en~1a~ to h~e a roll h~ving ~ ~urf~e formP~ with desired uneven pa~t~ern on ~he periphe~y~ Therefore. ~r orrni~}g thc desired or re~ular pat~e~ll of unevene~s h~
ts:~ be ~ rmec~ on l;he periph~r~l ~ur~ace of t:he roll.
Embos~-~re~ment on ~h~ m~t~ ate i~
general~y perf ormed ~y me~n~ of ~ dull roll hav i ~
tlrf~c~ ~ormed w~ th a de~l~ea uneven p~e~n 'co l~e tran~3~erred on t:he me~al pl~e ~;urf~ce. ~or orming the desired p~ttern o~ unevene~s 4n thç peripher~l s~ ce 0~ ~he roll, photoet~hln~ pro~ as di~ o~ed i~ ~he ,zo 3ap~nes~ P~tent Fi~t tun~xam:lned) Public~ n ~okkai) Show~ ~0-3~ for ex~mple, ~nd mech~nical ~r~atment d~cl.~d .in th~ .~ap~ne~ P~t~t Fir~t tun~xamined~
Publica~ion ~'Okk~i~ Showa 5~ 1, the ~apan~se Pa~en~ First ~unexamined~ Puh~ic~lQn ~Tokk~l~ S~ 0~0 fc~r exampl~ ar~ prupoæ~d. The photoetchi~ proce~
~ompl ic~.te ~nd ~hus ~u~e~ ~ubstanlci~l ~o~t: in productinn of ~h~ roll~ ~le~hanical tr~ment i~ le~
exp~n~ive in comp~ris~n wi~h E~oto~tc}ling. E~O~ V~L, mechRnical tre~tm~nt c~rl ~orm only random p~t~e~n of un~n~s on ~h~ per~phera~ surî~e of th~ ~oll.
~urthermore, ~ince ~he su~iai~nt m~itudR of une~ene~s cannc~ be` E~rmed ~y the process ~f ~h~t~tching~ ht ~hot dul~. ~reat~e~'c i8 perEormed on t:he ~ur~ce o~ the metal pl~te~ T~le~fter. dullin~ t:reatm~n~ for ~3r~nin~
3~ proj ec~ uneY~e~3S ~r depr~s~ing ~nevene~ whl~h h~
~Fe~er area a~ a `~ul~ o:e shot du~ re~merlt ~or _ _ _ ~ .. .. . .... _= . . _ _ ..

~320022 pro~Jidln~ ~r~ate; ~ontr~st. ~n ~che alte~n~tiv~ t f ~ni~hinq is per~ormed for the depresse~ pQrtion oE the metal pl a~, On the o~her h~nd. ~he J~panese P~ten~ F~ r~
~unex~ine~) Pu~ a~.io~ okk~1 ~ Sh~a di~:lo~es f~r~tion o~ e ~u~ed ro~ hot ~a~ng pro~e~ with maEk-ln~ o~ th~ ~e~ire~3 ~neYezll p~t~er~
~his m~kin~ proce~s tend~ to require ~?xtr~ ~ep i~
tr e~tment .
~UN~RX ~F ~
~he~e~re. it i~ ~ ob3 ~t of ~.he present inven~ion to pro~l~e ~ p~ rned met~l pl~e whi~h i~
l~s~; expen~ive to produce and can ex~ oo~
decora~.L~7e ~ppeArance wi~h hi~h ~o~ro~i~n resL~tan~e and ~,~; weather re~ist~nce.
Another o~; ect of th~ in~tion ls to prov id~
a m~ho~ for pro~ucin~ the p~'cterned metal pl~e o~ ~he inv ent ion .
Acc~din~ ~o oQe a53pec:t oE thR i~ven~ion~ ~n ~lneven pat~rned me~al ~tr ~ p or pl~t~ cording to ~h~
pre~ent lnvention, ~53 ~ormed s~ ~th an lneven p~ttern a~ ~
~u~face Aecor~tive pat:te~n. ~he pat~ern i5 con~tltu~:ed ~f on~ or m~re p~t~e~n u~l~. collt~ln~ plurAl lty o~
une~ en do~
~ch of the u~everl do~ h~ a ~iæe r~L lrhe une~e~ do~
~re ar~ang~d in a predet~rmin~d ~en~ity to have ~i~en r~iO ~ o~ occu~pyln~ ~rea ver~us plan a~ in ~a:Ld p~t~ern uni~- The ~ arld area ratio 7~ ~eirlg in a r~nge o~: .

Ac~or~in~ to the pr~en~ in~?ention, ~ uneven pat~err~ed met~l plate h~ving a ~urf~e~ on whi~h un~ven p~tt~rn 1s form~d ~y ~t lea~t orle pa~ n un~
~on~3ti~u~ y 1 plur~1 ity o ur~eve~ d~, e~h oE ~lFhl~h h~$ a ~ the un~ven dot~ h~in~ arran~ed in a pre~e~mlne~ d~nsity ~o have ~iven ~a-~;lo 1~ o~ occupy1 i3?~ 0 area vPrsus plane area in said pattern unit, said size D and ~area ratio ~ being in a range oE:

0S D ~ 300 (~m) 530S ~ ~100 (%) and the size of said pattern unit has minimum length of 1 mm.
In a particular embodiment the invention is direc-ted -to an uneven patterned metal plate having a surface, on which a visual decorative uneven pattern is formed by at least one pattern unit, said plate having a plurality of pattern units, said pattern units being separated from each other by unpatterned plane axeas free of uneven patterns, each of said pattern units being constituted by and with a plurality of uneven do-ts, each of which has a size D, said uneven dots being arranged in a predetermined density to have a given rat.io ~ oE the occupied area versus the plane area in said pattern uni-t, said plane area having a surEace roughness Ra which is equal to or less -than 40 ~m, said size D and area ra-tio ~ being in the range of:
lO~ D ~ 300 (~m) 30~ 7 ~lOo (~, and wherein the size oE said pattern unit has a minimum axial lenqth or width equal to or greater than 1 mm.
According to the present invention, there is also provided an even patterned metal plate having a sub-stantially flat surface provided with a specially patternedplane area, the surEace of the plane area being modified by the presence of a multiplicity of spaced-apart impres-sions formed in the plate and arranged in groups in accord~
ance with a predetermined pattern and at a prede-termined ,~

`` ~ 3~0~
- 5a -density on the substan-tially Elat surface, the impressions being positioned between plane areas and including peak portions which extend beyond the subs-tantially flat surface and depressed portions which extend within the plate beneath the substantially flat surface, - the impression having a size D which is the dimension oE the peak portion and which is in the range of 10 to 300 ~m, - the impressions having a surface occupation density which is the ratio of plate surface area occupied by the impressions to surface area unoccupied by the impressions, and which is 30-100%, - the patterned groups having minimum leng-ths and widths in the range o-f 1 mm or greater.
lS According to the present invention there is also provided a laminated patterned metal plate, the surface of which includes flat area and a multipllicity of impressions arranged in groups in accordance with a predetermined geometric pattern on the surface of the pla-te, - the impressions including raised portions and depressed portions extending respectively outwardly and inwardly of the flat areas, and - a surface lamination applied to the plate surface, the lamination being thicker at the flat areas than in the depressions.
According to another aspect of the invention, a process for forming uneven pattern on a metal strip comprising the steps Gf:
- providing a work r~ll for temper rolling having a surface roughness Ra smaller than or equal to 0.40 ym;
- performing dulling operation for forming desired uneven pattern to be formed on the metal strip, which uneven ~' c~2~2 - 5b -pattern is formed by at least one pattern unit constituted by a plurality of uneven dots, each of which has a size D, the uneven dots being arranged in a predetermined density to have given ratio ~ of occupying area versus plane area in said pattern unit, said size D and area ratio ~ being in a range of:
10S D ~300 (lum) 30~ ~ ~100 (~) .

and the size of said pattern unit has minimum length of 1 mm, setting the dulled work roll in a temper rolling mill and performing temper rolling for temper rolling and transferring the uneven pattern onto the surface of the metal strip.
In a particular embod:irnent, the invention is directed in a process for forming a metal plate having a substantially flat surface provided with a specially patterned plane area, the steps w.hich comprise dulling to the surface of said plane area a multiplicity of spaced-apart impressions formed in saicl plate and arran~ed in groupæ in accordance with a predetermined pattern and at a predetermined density on said substantially flat sur~ace, said dulling being applied by a temper roll having a sur~ace roughness Ra equal to or less than 0.~0 lum, said impressions being positioned between plane areas and including peak portions which extend beyond said substantially flat surface and depressed portions which extend within said plate beneath said substantially flat surface, - said impressions having a size D which is the dimens.ion of said peak portion and which is in the range of 10 to 300 ~um, - said impressions having a sur~ace occupation density which is the ratio of plate surface area occupied by ~,32~s~2 - 5c -said impressions to surface area unoccupied by said impressions, and which is 30-100~, - said patterned groups having minimum lengths and widths in the range of 1 mm or greater, and transferring the spaced-apart impressions to the surface of said metal plate.
According to a further aspect of the invention, an apparat-s for performing temper ro /
//// , ____ .. . ~ .

~L32~22 met~ lp ~ rm ~ d~ d ~n~n ~ on the ~ur~ce o~ the Metal ær~L ip~ comprl ~e~ a work r~11 for temper roll ing æormqd with ~ de~lr~d ~ne~en p~ rn orre~p~:nding t~ t.h~ un~ven ~r:t~En to ~e ro~med on ~h~

2.1 $! rip. wh~ e~ ae~ L
on~ rn ~ d ~y ~ ~n~v~
dots, each of wh1 ch h~ a ~i3e ~ the uneven cl~ts b~1n~
arra"ged in ~ predetermined d~n i-ty to h~v~ ~iven Y.a~i o n o~ occupyiny ~re~ versu~ ne ar~ hP pa~tern 0uni~ th~ si~e ~ and aYe~ r~tis: n b 1r~ in ~ r~nge of:

o o 8iL ~

3 ~ O

~nd ~h~ ~iæe of the ~ttern unlt ha~ minimum length of 1 mm~ and a tempe~ roll ing mill, .in whlch the work rol~ is ~o I:~e ~t f or per~orm~ng temper roll t n~ or t:f ~ er r i n~
the uneven p~.~t~rn onto t}3e ~ur~ac~ o~ the metal ~ rip~
20The wo~k roll i~ ~orm~d wlth ~h~ une~erl do~
cons~i-tutin~ ~;he un~ven pat~ern by me~n~ of hi~n density ene~9y h~am~ su~h ~s a 3.a~er ~e~.
The ~u;~f~ rouyh~1e~ Ra eg th~ p~ane area i~
~m~ller th~rl or e~u~l to O.~o ~lm. ~he urleven do~ is orm~d int~ ~;s*nti~ly ~ ular ~n~i~ura~ion h~71n~
th~ p~d~termined diame~r o~
~}le p~tkern unit ha~ ~ width o~ axl~l leng~.h g~ea~er than or egual t~ he E~tern unit 1~ ln ~orm vf a 1ine havin~ ~ width gr~t~r th~n or ~u~ o 30mm~ ~rhe p~.~t~rn uni~: in ~ form of 1 ifl2 i8 dl~n~
~ro~ the next pa~ ern uni~ ln a fli~tarlc~ gr~t~r than o~
e~ual to 1 ~n Th~ ~p~r~us m~ :Eurther con-pri~e ~ pl~ing mean~ fo~ f~rmin~ ~ pl~tin~ l~er on th~ ~urfa~e. The ~;pl~tin~ me~n~ ~orrn~ th~ plating ~ r having thi~krt~li thiGkne~3 ~t the ~roi ect ~ nc~ pe~k portion of ~aah un~ven L32~2~
~ot th~n thAt at the deE~ressec3 portion of each eve3l dot.
The temper rolling mill include~ axially drlvin~ mean~ for driving one or the work roll and a roll with plane surface and ~ontactirlg ~ith the work roll to caus2 relaLive shift in axlal direction. ~he ~xi~lly drivlng ma_ns ~lri~te;, the one of work roll ~nd the plane surfaee roll in shifting mayn~tude greAter than or equ;~l to half c:~f the intexval be~een the 1 ine~.
The relative shif t in ~xi~l direction of the work roll and the pl~ne ~urface roll is per~ormed con~inuou~ly.
The axially driving means dritres one of ~he work roll an~ the plane ~ur~açe roll in a 3hitlng ~peed 3ub~tantially lower th~n ~he l ine speed o~ metal ~trip ln tempe r roll ln~ prOce~s-The pre6ent lnvent~ on wlll be underst:ood more fully from the detailed description gl~r~n herebelow and ~rom the aecompanylng d~awlng~ of a preferred embodiment; oE the invention. whichJ however. ~hould not be taken ~o limit the invention to the specif'l~
embodiment b~t are ~or explanation ~nd Inder~tandin~
Ollly .
In the drawings:
Fig. 1 ~ ~ partial ~e~tion o ~ dull roll for 26 ~rming the p~efe~ed embodiment o~ a metal p~ate ~caordin~ to ~he ~nvention:
de-t~loped pl~n view o~ the dull roll o~ F~g~
Fig~. 3(a~ and 3(b) are ~- s~hematic illustra~ion o~ one example of ~ laser dullin~ device for performing la~er dulling oper~t~on~
Fig~ 4 1~ a front ~levation of ~he dull roll Of Fig. 1:
Flg. ~ n explanatory illus~ratlon showing one exam~le of p~ ern o~ unevene~ ~ormed on the dull ~oll;

1~ 2 ~22 ~lg~ G i~ ~ ~ec~ion sh~-~7ing the pr~ n :E~rming p~erned une~e~;s on the me~1 plate by m~n~
of ~he du1 1 ~oll of ~ig~ hroug}~ 4:
E`ig. 7 ~ se~tY Oh O~ the meial pl~te ~ormed wi~h ~h~ un~vene~s throu~h the ro~ n~ pr~e~s str~ed ln ~is. 6 J
Fig . ~ i~ a se c~ lon show ln~ ano~h e~ ~x~mpl ~ o~
con~ igura~lon o~ lln~v~ness orIs ed on ~he metal pla~e sur f ~e, ~lg~ a . ~ection ~f the p~t:te~3ned me~l pla~e ~ Fi~. ~. which is ~oate~ l~y ~ platin~ l~y~rJ
~lg. 10 1~ ~n ~xlar~ad pa3;~ial ~ectlon of the dull r~l ts s~o~ 'Ghe dimer~ion~ he unever~e~ me~
on the perlpheral sl;~rf ace ~hereof ~
graph ~howing relatioll~hlp between the depth and dl~me~r of ~h~ depre~sion of ~he unevene~;~ ;Eormed on the ~n~tal plate 3urface;
Fig. ~ 2 i~ a ~raph ~howing relation3h~p between the d~pth of dep~e~sicln an~ the producl:ioil co~t~
~pFi~. 13 ~ nd 13 ~ are pl~n v~ews ~howing vari~tio3~ of the pat~ern o unevene~ to be fo~ed on the sur~a~e of the metal pl~e;
Fi~. 14 1~ a pl~n ~ew o~ nple piec:e on whlch uneven~s3 is :~ormed:
25Fig. IS 19 ~ ~hart ~howing rela~.ion~hip be~ween pi~h o~ th~ aep~ ion to be ~orm~d o~ the met2~l plate ~ur~e ~nd ~h~ 8urf A~ rou~hn~s~ o~ ~he pl~te:
Fig. ~ a plan view ~ one exampl~ of te~
30pie~e t~ be ut~ ed ~or t~'cing di~inGtnes~ o~ the uneven pat~ern ~o ~e ~ormed on the m~tal pla~e ~iur~ce;
E!ig~ 17 i~ ~ plan v{ew o~ one emhodimen~ o~ ~
8k i ~ pa ~; r oli ~o he Ut il iz cd f Or p~ r;~ orm ing the pre~erred ~m~odimen~ of dul~ in~ pr~ s ;~or ~rmin~ ~h~
35des3ir~ pat~xn oE un~ene~ on ~h~ sur~ of the me~l pl a~e~

~320~2 Fig~ 1~ i an e~large~ pl~n ~iew of ~ porlion ~P the ou~er pe~phery of th~ ~kin p~s ~ f ~ig~
Fi~ is a ~ur~her e~ ged p~La~ v~w o~
portior~ o;E the outer periphe~y o~ the ski~ p~ roll o~
Fig. 18;
Pig. ~0 is 2 plan ~iew o~ the~ odi~ent o~ a sl~in p~s roll to b~ ~lliz~ for per~ormi~.~ tlle preferred em~o~im~nt o~ àullin~ proce~s :~or formillg th~
des~r~d p~ ern o~ unevene~ on the 3u~f~e o ~he me~l o P:L~teJ
Fig. ~1 is an erllar~ed pl~n ~ w ~f ~ port:lon o~ ~h~ ou~er perlphery o~ the ~kin ~s roll o~ Figi XO;
Fi~, ~a is ~ ~ra~men~y ill~tr~io~ of temp~r rolling mill ~o perform ~h~ preferred proces~ ~o~
1~ formin~ de~lre~-pattern on ~he me~a~ pl~ ;ur~ace;
Flg, ~3 1~ an expl~n~ory illustr22~ion ~hown proce~ ln ~rans~errln~ . of th~ url~v~n pa~ n on the dull roll ~o a back-up ~oll?
Fig. ~4 i~ ~n e~pl~na~or~ illu~tratlon of th~
~u dull roll perf~rmin~ dull in~ oper~tic~n:
E'ig~. 2~ t~) ~n~ b~ ~re ill~tration~ of ~he dull r~ll perf~r~in~ dullin~ operation ~t d~erent ~hi~ ition~;
Fiy~ ; a ~ra~ment~r~f illu~tra ion v~
not~r eml~diment o t~mper rs:)ll in~ m;ll ~o~ per:~r~hin~
dull in~ o;pera~ion ~o p~v~luce ~he pr~erred embo~imsnt 9:E
l~he p~ t~e r n~ d ~net~l pl ate i 7 i~ an il~ r~t~on ~h~win~ pro~e ~ o~
tran~3f erring the ~n~ven p~t~ern on the dull ~oll tQ a~
interm~d~ a~ ro~
Fi~. ~a i~ ~n ~xplan~tory illu~ tion o:~ the dul~ ~oll p~?r~ rmlny dull in~ oper~ion~ ~n~
Fiys. X~ and 2g ~b~ are l~lu~r~t~ ons ~ the dull roll pe~ rming dulling op~ration ~ diffqrent hift p~ltlons~
q OF T~ Pi~E:F~ E~
_ ._ . . ~

_ _ . . . ... _ , . _ `` 132~022 ~o ., The preferred embodlm~nt o~ a ~errlea ~net~l pl~ 3 ma~e of ~ ~;t~l pla~e. The ~eel pl~te to h~
p3~0duced accordin~ to ~he pre~en~ inven~n, 1~ ~Qrme~
3f ~ plurality of uneYenes~ ch c~n~t~ tut~ o~
conic:o-~lin~ric~l pr;~i~c~ing por~ion ~7hlch proiect~
f rom t:he genera3 s~r~a~e o~ the ~t~el plate~ ~nd ~r~r~ r ~roove portlon extendln~ around ~e pro; ~c~in~ p~rtion.
E~ch o~ the un~ve~e~s a~ the ~om~ination of ~he pro;~ec~ing po~ n and ~nnul~r g~oo~7~ will be here er la re~erred to a~ ' 'un~ven dott r~ thlOU~hC)Ul~.
Tholu~h the Bp~!cif iC em}~odime~t of the patte~ned met~l pl ~t~ emplqy~ the uneven d~ consti~ t~d of coni~o-c~lin~ri~l pro~ec~in~ portion whi~h project~
from lthe ~ene~al ~urf~c~ Df the st~el platel ~nd a~nula~
~6 ~roo~7~ po~lon extendinç~ a~o~na the proj~ctin~ por~ion~
a~ ~nit unevene~s for ~ormin~ an une~en p ttern, Conf iguratlon c7~ the uni~ lme~enes~ i5 not: ~pe~ ied ~o the ~3ho~,7n one ~t c~n ~e oi ~ny appropri~te or ~e~ired ~on~i~uration~, Fo~ ex~mpl~, the p~o~ecting p~r~ior1 c~n be es~en~ially p~lyhe~ric ~.on~igur~ion i~ deslred, The~oreJ the ~11 owing dlscussion with re~pe~t to the speci:~ic ' con~igur~ion of uni~ un~vene~s ~E~r corl~titutin~ the desired uneven p~ern ~hould ~e appre~ e~ ~6 me~e exa~npl~ ~or i~nplQmen~ing the pre~nt inq~nt~ or~.
A plu~lity a~ ~he une~ren ~ot~ are ~ n~ ~o e~4h ~ther ln ~ pred~t~rmin~d p~ern an~ at pre~ete~nlned ~ensity ;Eor ~ormin~ ~esired ~lneverl pattern on the gu~-f ~c~ of ~:he steel pl~te. Such unev~n pattern ,~Q i~ formed through temper rollln~ proce~s utlli~lng dul l e~ wo~ oll ~ . The ou~e~ iphery o~ ~h~ w~rk rol~ s i~ dulle~l ~o ~o~m a pr~deter~nine~ c4nf i~ur~tion o~ unevenea~ ~ach ~onæ~itu~ed ~y a d~E~re~sion 1 which e~ntially confo~ms o the ~oni~o-~y~ lndrical 3~ pro~qotin~ portior}, an~ an ~nnular proje~tion 2 whi~h oon~orlnS ~he annular gr~ov~ -o~ the metal pl~t~. The ~om~ine~ d~pr~s~i~n 1 and the ~nnular pro~ eF!t:Lon ~ as 1unit unev~rle~s to ~e ~orme~ on th& peripheral ~Ir~ e of ~he work ~oll wlll ~e refex~ed ~o a~; ~ ' impLe~sio A~; seen ~ro~ ig~ nd ~, the l~npre~ion ar~
~rr~ed ln spaced ~p~xt rel~tion~hip t~ h o~her with lea~ing blank ~e~ ~, on whlch the ii;lpr~s~ion i =. no~
f or~ed and main~ained ~n fl a~ In o~he~ word~, -th~
imp~e~ion~ ~r~ sp~ce~ b~ the bl~nk ~ea ~.
Tn ~he preferred em~odimen~. the ~en~lty ~ of ~he ~neven dot and the ~l~e 1) ~ o~` the ull~Yen dot ~rc as folloWi 1 0 ~ 0 3 o ~ l o o 1~
The uneven dot~ ~re ~r~nged to ~orm one o~ mo~e groups, eaah o~ ~}~l~h ~rou~?~ wlll be herea:f~er referre~
' luneven pa~-tern unit' ' Thi~ uneven pat~e;cn unlt~ are ~r~n~ed to f~orm the desire~ neven ~ttern wi~h ~ectic)n of the m~tal pl~te ~urf ace ~here the lln~v~ne~s i~ not ~orm~d, which ~e~ n i.~ re~erred t~ R~ ~ ~eneral sur:~ce ~ctlon~ ch patt:e~n unit occupi~ area ~-he ~teel pl~ u~ac~ in ~ form of ~ircu~ar form.
ce form. pol~on ~orm an~ go ~orth. The minimum dlam~te~ or wid~h of the u~e~n p~t~n uni~ i~. 1 mm. Orl the c)ther hand, th~ ~ene~al ~urf ~e ~ect ~n m~y h~e W$dth o~ ~ ~
There~ore~ th~ impx~ion~ to be ~ormad ~P the w~rk roll ~3urf ~G~ ~orm one o~ m~re group~ ~orrespon~
to the une~en pat~ern un~ t on the s~e~l pl~e. Th~
~roup~ o~ impre~sion~ ar~ arr~n~ed wi~h lea~Jing ~h~
~e~on where ~h~ impr~s~ion i~ no~ :Eormed~ in the P~Rxn ~rre~punding ~o 'ch~ e~en p~ttern on ~h~ ~teel pl~te. Proc~ of ~ull ing ~e w~rk roll ~o :orm ~h~
de~ired p~ttern o~ L~ne~ene~ on ~he peripher~l ~ur~ce W .L~ 1 ~e di ~u~ed her ~bel ~w ~

13~22 In the pr~f~rred p~o~ , the per.iphe~al ~ f~e o~ th2 work r511 i~ su~j~ct g~1ndin~ ~e~men~
for ~ri~ht ~in:~;hin~. in ~dv~n~e ~f forming ~he impre~ion3. ~hen) lrnp~es~ion i~ formed on the p~ripher~l surf~ce ~3y ~r~ di~ hi~h d~n~ity ene~
~e~. I~ the sh~wn em~od~ment. ~ las~r ~2m i9 ~elet~d As ~he hi~h den~i ty ener~y ~e~rr ~or f o~min~ l~he impre~sion on ~he pe~iph~ral surf ac~ of tnc work roll ~
Irr~dl~ g the la~er be~n~ onto th~ peripher~ ~u:rf~ce Rf the work roll ~, th2 ~nat~ria~ at th~ irradiati~
poant i~ Tnolten or fuse~ ~o c~ pori~ n ~o ~orm the depre~;ion 1 and the ~.nnular p~o~ ec~ion ~ ~EOUn~ the depre~ion.
The la~er ~ n to be u~ed f or d~ll ing t5 ~peration 1~ ln a ~ange o:E ~OOW ~o 2~00W~ If i:he l~er i~e~m oE lower than C~OW is use~ 'ch~ las~ beam ener~y will l~q in~u~-Eicien~ ~or ~a~isfac~or~ly fu~3e l~he material 3teel of th~ work roll to form the impre~ion~
On the o~h~ h~ncl. when the la~r ~e~m er~ergy be~:om~s ~xc~ive to mAke tl~e cos~ ~or energy be~m unec~s~rlly higb. ~n ~dditi~n. wh~ he lfa~er beam ~ner~y i~
~r~ater th~n ~500W. thermal cleformation tends to o~cur On the lena i n laeer machinq) ~o CAU~e l~ngtabil i~y ln l~ser mocle ~o r~ dif~iCUi~ in rou~hn~s con~r~.
;25 A~ ~S;i8~ uch ag oxygen ~s ~ m~y ~
~i~ch~Lrged ~o~rd th~ la~r b~am i~diatin~ point for ~sistirlg fu~n~ o~ th~ m~erial ~eel at the portion ~
~orm ~he d~pr~lonO Th~ ~Sl~t ga~ m~ ~e discharged ~hrou~h An ~ssi~3t gas ~ harge no~zle whi~h i~ incl ine~l i~h respect to ~h~ pl~ne laying ~u~s~n~ ~lly pe~p~n~icul~r to ~e ~xi~ o~ ~he l~sç~ beam~ In ~he pr~erred ~yout, the a~;~;is-~ gas c9isch~r~e ~o~;~le i~ in range o:~ ~0~ ~ 90-The :l~ser m~ch~ne to us~ the ~or~oing dtllling 3~; operatiQrl m~ be ~c~ de31gned ~: to lnt~rmltten~ly . lrr~dl~tin~ the la~ be~m with ~ p~dete~mined t32~22 -- ~3 ~

ln~erval . The ~a~er m~ ine m~y be ~ nterm1 l~erltly ~hifted in ~ dir~ction par~llel to th~ i~lXi9 o-f th~ work roll at ~ given magnitud~. Thi~ ~hi~ing m.~sni~ude determine~ the axial p~ t~h ~f the ~r~ Eer~n~i~lly ned impres~ion~ to be forn~ed on ~he p~riph~ry o~ th~
work r~ll. On tke ~th~r h~;nd, ~h~ work roll m~y ~e dr~ven ~o rotate ~t; a gi~en rot~ion ~pee~ h ~hi~;
rotation spe~d of the work ~o~ 1 and ~he lntermi~ellt ln~e~val of la~er be~m lrrAdY a~ion~ t:he el~um~er~n~lal 0 pit~h o~ the itnpressivn~ c~n ~ ~ete~mined.
One example of ~he la~er be~ ~nachining appar~tus ~o~ per~orming ~he l~ser dull in~ operatiorl to ~orm th~ d~ired pattern is ~no~n in Figs. 3 t~ ~nd ~b). In th~ ~hown ex~mp~ h~ work roll ~ 1 ro~in~ly upported by mearls of a fc~ll 6~lpport 12.
~ho~h it is no~ cle~rly ~hown ln Fi~3. 3~a~ and i~) P
the ~oll support: 1~ incluc~e~3 a drlvin~ m~h~nl~ r rotating1y ~rive th~ ro~l 3~ The dYiV~ mechani~m i~
a~so~iated with a r~l~a~ion ~peed ~ontroller ~4. ~he ~aser beam gener~tor unit ~0 is p~oYi~ed ~n ~he ~,riclni~y i~ the roll ~Upport. Th~ l~.ser be~m gener~t~r unit 20 include~ a de~le~tor a~sem~ly ~4 ~vr d~ c~inq ~he ~ener~ted la~er be~m alon~ a l~ser b~m p~th 25~ P.
de~le~tor nlirro~ 24~ er~ed wi'chin th~ 1~8~ ~e~Tn 25 . path .~ ~or de~le~l:in~ t:he ~a~er l~m oU~;~)Ut f rom the b~:3er beam ~ener~tor Llni~ ~0 toward ~ laser h~a~ unlt 26~ The l~er he~d unlt: ~ in~lude~ ~ lens ass~m}~ly 3d ~ USing the. laser be~m onto the predetarmirled ~pot on the periphe~ ur~Ce oP ~he w~xk r~ an~ a ro~y ~hoppe~ 3~. ~he rota~y chopp~ 32 ~erves f~r ~e.nera~ing pul~tile l~.~er be~m to he irradiated on-to th~3 roll periphery~ The l~r he~d i5 moUrlte~ ~n a l~ser h~d ba~e ~4~, on Which ~uide r~ re mounted in 3ubstan~ially tr~n~ve~ fa~hion wikh r~p~ c4 ~h~
lon~itudinAl axi~ o~ th~ ~ork r~ïl. Th~ la3~r h~d uni~
26 is mo~ble towax~ ~nd ~w~y ~.r~m ~he work roll ~u~aae ~32~022 ~long the gu~d~ r~il ~ m~na of ~ drive c9etv~ 2~. ~?n the other h~d. ~he la~er he~d ~ase 34 i~ mov~ble ;Ln a dlrec~ion parallel to the lon~itudinal aYri ~; C!I the work roll 3 . The driv~ mechan~ g~n c~mpri~es a ~;piral rod drivingly me~hin~ wi~ c 1 2ser he~d ~5e T~r çau~ing ~xi~l ~hi. t: of the ~2~e with ~e 1~ ~ he~d ~nit ~ ~n ma~n$tude cor~es}?onding t~ th~ ma~nitud~ of rot2~t:Lon of ~h~ ~pi ~1 rod.
~n dull in~ oper~tion, ~ince the la~er beam i~
tO ~ocu~ed ~nd lrradi~ed ~8 ~u~st~ntlally h~gh d~sity energy bea~n, the lInpre~lon3 ~r~ ~orrlLed on the r~ll ~urf ~e ~ stant:ially ~t ~ motnent~ Narnely~ irr~di~ti~n oi~ th~ er b~n causes melting of ~he ~urfa~e ~ erlal to c~u~;e vapo~l~ation o~ ~he ma~r~ k the l~r ~e~m i rad~ a~ing spot ~o form the ~epres~ior~ d the annul~r pro; ecti.on.
In order to adj ~t in~er~7al of t;he imp~e~s~o~
in circum~erenti~l ~nd axia1 ~irections, a control ~ys~e~n is provide~. The con~trol sy~em incl~ldes . ~stem :E~r m4nltorin~ the ~urf ace condition of ~he work rOll on whi~h dullin~ op~ation ls performed.
Th~ roll ~urface rnorll~orin~ me~n~ in~l~d~ a l ight~ ng d~r ice ~hich includ~ l ight ~our~e u~ 0 ~s ~ li0ht ~ource unit 40, ~ ~roho~opic ~i~ht sou~
i~ u~ed. The light ~ou~e uni~ i~ conneGted to ~ light pa~h 4~ whi~h compri~s an optic~:L f ih~r. ~h~ llght p~th 4~ urc~ed ~t ~ha ~nd into tw~ ~r~n~hes 4 And 4~. B~h ~f the bran~ha~ 4~a and 4~b ~re cooperat.ed with an optl~a~ d~e~to~ he~d u~ s and ~0 directed ~o ~ common m~nitorlng point ~ the work rall u~ e. Th~ opti~al d~t~ct~r unit S8 includes shutt~
~a and ~4~ ~or ~tabll~hin~ an~ ckin~ light p~th f ~om the ~n~ ~f the hr~nch~ 4~ a and ~b o~ kh~ 1 igh~c path 42 t~ the mon~torin~3 poln~ M. In th~ p~e~eL~c1 3~; ~on~tructionl th~ shutter 54~ ~nd S4~ ~re ~p~rl an~
clo~ ynch~onou~ly to e~h o~heri OFI th~ othe~ hand.

- IL32~%2 - l$ ~

~he ~hu~ter ~4a and ~4~ m~y ~e dri~e~ ~o open an~ e ln asynchronous m~nner.
~he liqht beam m~ ~e irra~l~t~d ::Erom ~ ~ommon plane including no~ exten~lln~ f rom the r~ a~e.
The ~3~r~dl~tion poirlt ~xe sele~t~ on the ~l~or~mentloned pl~ne to ~ symme~r:ic to each o~har wi~h re~p~ t l;:o ~he normal and to h~v~ ~n incldent ~ngle gre~ter than or e~u~l to ~~
Oppo~ing ~he monl~orln~ point M. an im~e to pick-up de~ e 44 i~ pro~ ided~ The. i~nag~ pl ~k~up ~ievice en~ployed in th~ shown aon~ru~ion is desi~ne~ to pi~k~up ~n enlarged ~till i~2 ~f ~h~ r~ r~ce a~
~he monitorlng point~ For ~ul;omatic~lly focu~- ng th~
image pick-up d~ce 44, ~n ~oc~l~in~ device 4~ m~;y be 1~ combined wi~h t.h~ ima~ pick-up ~7L~e 1~ ~or~r~ected ~o ~
di~play monit.or uni~ 4~ and ~n image data proc~e~slng unil; 5~. The im~ge data pr~c~ing unit SO proçe~e~
the im~e ~at~ lnpLlt f rom the image pick-~p deYice 44 ~o deri~e an output ~i~n~ he ou-~put 8ign~1 is then 7~1 C)U~pUt~ via an outpu~ unit ~2. ~he i~na~e d~t~ pro~s~in~
unit ~O i~ al~o c~nnec~ed t~ R ~imin~ control uni~ ~
an~ ser cvn~rol unit R~. The timin~ ~:ont~col unit so control~ ~he irra~iA~lon tlmlng3 of th~ h~ be~m a~d im~ge pi~k-up. On the othe~ hand, the l~se~ contr~l .25 u~it ~2 ~n~rol~ aper~tioll of the drive us~i~ 2~ for adiu~in~ ~:he ir`r~diati~n poin~ of the l~ser be~m on ~h~
Wo~k ~oll ~ur~ace ~nd oper~atl Oll 9~ the ~h~pper adjusting la~r beam i~radi~tion timis~ and lrradiati~n per lod .
On; th~ o~her h~nd. the im~e p.ick-~2p de~ i~e ~
i~ hc~se~ ln ~ hol~sing 4~ whiqh i~ moun~d ~rl a mov~le ba~e~ ~;uid~ nd ~2 ~re provided :Eor all~w~n~
tn~v~men~ of ~he hou~in~ . ~S ~n tr~n~v~r~ ~r~d ~xi~
d1 re~ n~. ~rh~ hc~u~in~ 4S 1~ as~iated wlth a drive means ~no~ ~:hc~wn~ ~cv be driven tow~rd an~ aw~y i~rom the monitorin~ p~;~int M alony the ~uide ~0. On the ~.h~r .

~ 3 ~ 2 hand, the housing 45 is driven by the driviny means in axial direction along the guide 62. The axial movement o~ the housing 45 with the image pick-up device may be controlled in synchronism with axial movement of the laser head unit.
With the foregoing laser dulling system, the impressions can be formed on the psripheral surface of th~
work roll in the predetermined uneven pattern which corresponds to the uneven pattern to be formed on -the steel plate surface through the temper rolling process.
The size of each individual impression can be controlled by intensity of the laser beam to be irradiated onto the surface of the work roll and the amount o~ the assist gas to be discharged toward the irradiating point o~
the laser beam.
The method and apparatus for dulling the work roll surface have been disclosed hereabove in terms of a specific example.
Though the shown embod.iment is directed to the specific configuration of the impression to be formed on the sur~ace o~ khe work roll, namely that constituted by the center depression and the annula:r projection therearound, the configuration of th~ impre~;sion is not necessarily speci~ied to the shown con~iguration. ~amely, the annular projection is not necessarily a se~uence of ring shaped con~iquration but can be two or 3200~2 ~nor~ arc ~h~pe~l p~o~eckion~, d~s~o;~l~inued with ~iv~n interv~l. On th~? ot~her h~n~. the proje~tion aroun~l ~hio depress1on 1s n~ lw~ys rlec~e$~ary~ In c~se that ~nly ~epr~ssiorl i~ to b~ for~e~, tehe amoun-~ ~f ~h~ is~
to ~ ~ischarge~ ~ow~Lrd the la5eI~ be~n 1rr~di~ti~ point wlll ~e ~o adju~,ed ~s not: ~o ~use r~-eol 1d~c~lo~ Ot-the voporiæed materi~l around the upper ed~ por~ion o~
thT~ depression~
Flg. ~ ~h~w~ ~ over~ll pl~rl v1ew ~f the work roll formed with the pred~t~rmtned uneven ~.tern. In Fig . 4 . ea~h o- ~h~ ne illu~tx~e~ ~ ~h~ l ine on the work roll ~urf~e ~omprisc~ h ~roup of impre~Sions cir~um~erenti~ nd ~xl~lly ali~n~
~co~in~ to the d~irP~ p~.tern. On e}la~Qpl~ of th~
1~ p~t~e~n to arrange ~h~ impre~lons in ~hç gr4up~ i~
shown in Fig~ S . A~ n f rom E`ig. i t each ~roup oE ~h~
impre8~3l0ns on the work r~ ur~ace i~ con~ti~uted ~y plurality ~ Lmpres~ions a~ igned in ~ircumferen~ial di~tion with a y~verl irrt~rvals ar~d ~xl~ arranged in ~o ~ en pl tch.
Wi~h the ~ork ~oll cons~ruoted a~ for th ~hove, tetnper roll in~ ~per~tiion is ~erf ormed~ ~u~in~
thi~ temper ~ollin~ pro~e~;s. khe uneven pat~ern forme~
on the ~ork ro~l ~ur~c~ 15 tr~nsEerred to the ~teel pl~.e ~urf ~e throu~h the proo~ hown in Fl~
Nam~ly, the work rol~ $ d~pre~;se~ ~h~ ~st~el pl~e ~l~rfa~e. ~y the pre~sure to b~ ~xerted ~ the w4r}~i . o 3, the po~t1 on of th~ ~teel pla~e which ~nate~ with ~he annul~r proj~lon ~ of t~ pre~sion is dep~e~ed ~o 3~? ~orm ~h~ annul~ ~r~o~e ~l wi~h ruun~l~d ~aper section ll sen~in~ towR~ ~he ~op o~ ~h~ ~oni~o-cylindri~al proje~tion l~. The materl~l c~u~ plasti~ w oE
~ib~r ~o~qa~d ~he portion m~ting ~h~ depre~lon 1 o~ ~he impre~ iorl of the work roll ~ J as sho~7n ~ a~row ln E~ig.
3~ . There:~or~ ~he coni~o-cylindri~al projec~ion ll~ wi~h a ~la~ ~p ~ur~e ~ i~ fo~m~d.

3~0022 l~urin~ t~is t~npe~ rool~ng ~per~tion~ ~h~
portion of the ~eel pl ate 7 whi~h m~te~ ~he pl~
peripheral ~urf~e wh~e the impression i~ not for~ne~, t ~s gen~r~l ~urf~ce ~S~ction 9 . As ~Pen f rom 7 . due iD pla~ a-t~ri~l fl GW t:ow~r~3 the portion wher~
~h~ lco~ylin~ri~al pro~ction lo 1~ ~Orriled, ~h~
~e~ation c~ the ~la~ top ~urface ~ . of th~
conico-cylindrieal proiec~ion ~ ome~ hlgher th~n th~t of the ~ener~ su~ace ~e~lon ~.
~L~ A~ t ~:or~h abQve. ~h~ ~onf i~tlr~ti~n of the uneven d~ to be orn~e~ on l:he ~-te~l pl~te 7 1~ no~
~p~cif ied to the con~ l~ur~tio~ ~hown in Fi~ . 7 ~ Fo~
example~ if th~ annu~r projec~ion i~ n~ forme~ a~u~
~he d~pre~ion, ~he ~onf lgur~t:i~n of 'ch@ uneven do~ to ~e $orrned ~u~in~ ~he ~emper roll in~ p~oce3s ~c~nes ~o ha~e only conico-~yllnd~ical proj ec:t;on a~ shs~ n 1 8, The ~te~ pl~e whi~h i$ f orm~!d the prede~ermlned ~ ven p~tern ~hrough th~ ~emper ~oll in~
pro~egs, ~s ther~ ~u~jec~ su~ac~ treatment~ ~ sho~n ~i~. 9. ~n the prei~erred pro~e~e, the ~ur~ce treatmen~
i~ pel~orme~ by ~in platin.g. ~hrosnlum pl ~in~ or 9~lv~nlza~ion ~o provide oorro~3ion r~istance ~nd We~th~r resl~t~n~e ~or the stee:! plat~. In a~dl~lon. ~
,~ plating of tin, ch~om~um or ~ incj the u~ven paSt~rn on ~he ~urg~ce c~f ~he ~teel plat~ b~meR deElnit~ to pr~l ide ~ood dec:o~ ive ~ppe~ra~ce .
Ir n~cessa~ tr~n~par~n~ r~sin ~oat~ng layer m~ b~ fc~rme~ or~ the pl~ting laye~ ~o ~L9 ~:0 ~ur~her pro~ e he~r corrosion re~1st~ne~ ~nd we~the~
~si~ ce ~or ~he ~eel pl~te~
In ~h~ pl~ing proce~s, ~in~e ~he ~e~l pla}e :~orme~ with ~he uneven ~tern in th~ pre~r~ed proce~
a3 ~et ~orth ~bo~7e. ha~ gr~ate~ 1:at ~L~!~ th~n tha'c of h~ ~eel plate which i~ fo~ned un~v~ss ~ the sllrf~ce w~ o~ ~ho~ bl;~ting or elec~ric sp~rk erosio~

32~2 ~urface are~ ~e~omes ~m~lle~ ~h~n that o~ th~ latt~rs~
A~ ~ ~e~ult, r~qulred amounl; of khe p~tin~ m2~rlal be~omes ~maller~ In o~her word~ with the ~ual ~noun-~
of the pl~tin~ materiAl, ~he ~t~el pl~e ~cor~ln~ to t~he pr~sent 1 n~n~ on ~an ~ r~.ed thi~k~r pla~ing ay~r. ~hl~ c~ e~rly p~o~i~e~ Det~er co~rosio~
rcsis~ance and we~the~ r~;i$t~n~e in ~ompari~on wlth that ~reated by ~;hot ~ ting or ~park h~rdenin~
Further~nsre, ~8 is w~ hown! in case of ~o ele~tro~pl~tln~, int~ y of platin~ c:ur~n~ ~e~om~
hi~her a~ the proje~tln~ por~lon th~n ~h~ in ~he ~eneral section or depre~ion. Ther~f ore, in ~h~ ~how con i~urati~n of the un~t dot~ ~he thi~k~e~ of ~h~
pla~ y layer in v~riou~ section b~come~:

Tl ,2 T;2, ~ ~
where T~ hickn~ o~ plating l~ye~ ~t the top ~ o-f ~he coni~o-cylindri~l proj ec~ion 10, T2 i ~ ~ thiRkn~a~ o~ the pl~tin~
i ~y er a~ t:he ~ ne r al ~u x f ~a~ t i ~n 9 ~ and T3 i~ a thickness of ~h~ pl~in~
the dep~ssiQn 11.
~ .
~hls vari~tion o~ thi~:kne~æ o~ the platin~
layer at variou~ se~t.lolls of ~he uneven dQ~:, provide ad~ant~ge ln exh~ in~ b~tte~ corrosion re~ls~
we~he~ r sis~n~e and in a~dition~ wea~ ~e$i~tarl~e.
~in~e the top of th~ proj ection t~nd~ ~o be expo~ed to th~ en~ironment. For in~tance. ~h~n ~u~h 8~eel plate i~
U~ed ~C~r formin~ a 6~eel Cont2~ine~, ~he top ~ of th~
Coni~o~cylindrical pr~ction tend~ to c~nta~ Wlth t~he 3S content in ~he co~tAi~er t~ ~ub~ect Wearin~. Thls ~l~o pxeven~ he k~ear m~erial o~ the ~teel plate f rom bein~

~320~22 exposed and thus prov i~e ~ercter ru~t-proo~ e:ELec~ .
~re, discus~;ion will be ~lven with rq~pect to the prefe~ed uneven patt~rn to r~e forrn~d on ~he Sll~f~ e o~ t:he ~teel pl~e. tn order ~o mak ~he followin~
~ u~ion to ~ ea~lly unde~ s~ood, ~ 0 s~ow~
~ en~ion~ lationshlp of ~ach i~es~i~n t^o ~e -F~:me~
on ~h~ work ro~l A As ~een f lom ~ig. 10, the ext~Ln~l di~met~er o~ the annular proje~tio~ ~ which dç:~ines the . ~o~der ~etwecn the impre~sion an~l the g~ner~ Lfae~
sectlon and thus de~ine~ the ~i~me~rical ~l~e o:~ th~
impres~3ion~ i~ D ~m and ~h~ depth f rom of the depre~sion ls ~ ,~m. As will ~e n~turally app~ecia~ed, ~7h~n t;he diamet~r ~ is in~rea~ed~ the dep~h ~ o~ the dapre~;lon ls also increased. In the ~xp~rimen~. it W~5 ~ound h~t. when ~he d1ameter ~ ~ecome~ great~r ~h~.n 300 ,LmJ
magnl~u~e o~ increa~ o~ ~he depth b~om~ nif i~n~.
In gene~al, temper rol~ln~ srformed ~or ~h~pe ~orreotion an~ ~nd ~urf a~e ~emperin~. In order to ~comp~ l~h bo~h~. relati~el~ hl~h pr~sure should ~e ;?O exerted between the work roll ~nd th~ ~te~l plate. This leads hiSlher tL~nsfer ~ of the impre~sion on~o ~he ~teel pl~te sur~a~e. There~'or~) wh~n the diam~ter of the lmpre~sion 15 12rge ~nd thus th~ depth ~ ~he imp~e~ n becom~ deep~ . the coni~o-~yl indrie~1 projec~lon to ~e ~orme~ on ~he s~eel pl~e ~ur~ac~
b~come~3 ~;ubG~antlally hlgh~ Aa ~ ou~ order ~o -fo~m hitd~er conico-cylindLlaal pr;~ ion, ~re te amountr o~ pla~tlc nla~rial flow ~s req~ll red~ Th~re~ore~
when ~he h~lght of th~ p~o~c~ion to b~ forme~ i5 so exce~ vely hi~h, ~ub~t~n~ Lly ~mall de~ct~ ~nds to ~e ~ormed ~round ~h~ pr~ ecti~n. In thi~ ~tle~r~ the ma~imum ~iame~ o~ the impre~on ~ ~et a~ 300 ~m~ On ~h~ other hand, when th~ diame~er ~ of th~ impr~ion i~
too, ~;ma~l, uneven p~tt~rn o~ the ~teel pla~e c~nnot bR
deflnl~ely re~oyni~d ~3verl wh~n ~he inlpre~sion ~
. provided ~ hi~h c'l~n~ity. E~pe~ially, when ~he diame~er `~

~32~2 e~rne~; ~m~lle~ ~h~ m, t~h~ r~fle~ ~n~ p~
on the ~eel plate b~om~ inde~inite. Therefor~, ~he ninimum ~l~meter o~ tha Impre&sion i~ ~et~ ~;t 10 llm, It will b~ ~pprecial~e~ th~t the unPv~n p~tt~rn on the s~eel pl~e will no~ re~ogniz~d ~ ~he ~i ~ of ~he Ime~7en dot ~ be forlr,ed hut ~y d~n~y ~ ~he ~ev~n dot~ ~nd presenee or ~,bsence the~e~r Therefore.
~u~ n~i~lly height ~f the uneven do~ i~ not required.
On ~he oth~r hand. i~ YieW ~ he cost. it i3 to not e~on~mical o f ~xln the d-~p d~pr~ion slnce de~p depre~ n require~ ~drea~er gri~di~g m~nitude in reproduction. This lncrea~es production co~;~ or cos~:
~or tr~atment o~ th~ work roll. co~t ~or ~xea~ment of the w~rk roll ill rel~ n t~ ~he ~iame~er of he imprl~S~io~ e forme~ i ~hown ~n Fig. 1~ In Fi~
1~IJ ~olid line represen'c~ ~ r411 ~o~ ~f the work roll and brok~n line x~pres~nt~ trq~atmen~ ~o~t. A~ will b~
~een ;Erom E~ig~ 12~ ~hen the di~meter ~ hecome~ greater than 300 ~Im, th~ roll ~os~ ~crease~ ~u~tanti~
zO Ther~ore~ in ~hi~; vl~wl it i~ pre~erre~ o l imit ~h~
~iam~er D o~ ~h~ impresæion t o be ~maller ~han o~ ~ual to gOO ,um.
~n the othe~ hand. tb~ r~l~tlv~ are~ ) of th~ impre~ qn can be ~e~ined by th~ di~meter ~ o~ khe ~; impre~;ion ~nd 'che c~nter~*O-aenter d~tançe SIT ~L~
~w~en adj~cent impre~s~on~. ~he relativ~ ~rea 1l a~n ~e given }:~ t~e ~ollv~Rin~ equ~tlon:

In ca~ Sm ~o ~ D

In ca~e Sm t~,~ c~ ~ t~

i3200~2 On th~ ~ther h~nd. th~ density N tnum~er 4!-impe~slonS in ~ uni~ area ~ n bc obt~ln~d :E r~m the ~ollowing e~3uation:

N D ~ . ( 3 ~

From ~he for~oi~g eqSIation~ {1), ~? ~ alid ~ he ~ollowing eq~ ion ~an be ob~in~d:

In ~ Ae Sm rl = 4 ~--~ O~ D~ . N

In ~se ~m ~ D

4 x - i o- ~ D
.
;j~o - 1 1 5 D 3 . N ~o 9~1 ( 10 D

lo~ , M - 1 As~umin~ the di~neter I~ of the impr~ o~ i~
~6 ~ons~ant, ~h~ rela~ive ar a ~ omas p~op~r~lon~l to the den~ity N ~ th~ impre~ion~. In or~er ~o dete~mine ~he ~p~imal d~n~i~ and ~hu~ optim~l relatiYe are~ of the irnpressivn~. ~mpl~m~r~t~ were t~k~ plaoe~ -~:n the experiment. ~ample pie~s h~1ng ~lz~
of 100 3n~n x 1~ mm. The sample piec~ i~ sh~wn ln Fig~
14. In ~ . 14, de~o~e~ ~n~ral sur~ace ~e~tion, h~ c And d ~3how~ ctione in which impre~s~ons ~r~ formedO
Si~e o~ the ~c~ions ~. c and d are re~pe~tiv~ly - 0,~ n~ x 0.5 mm. 1~0 ~n x 1~0 ~ n~ m x 1.5 m~n. Xn ex~erimen~ ampl~s piec~ h~vin~ mutuall~ di:~ferent ~urf~ce rourlhn~3~ R~ in the s~a-~lons ~ w~re prepared, 32~22 The ~ur~c~ rous;hnes~ ~ o~. re~pe~tlve ~ample pieces ~r~ 0.f~ m. 0.13 ,lLm~ ~2~ ,um~ On ~he other h~nd~ ln the ~mple plec?~ the relLative ~r~
~ were v~ried to 100q~. ~Oq'o, ~5$, ~o~b an~ :L0~. Th~refore.
tota~. ~3 d~~erent com~in~tion~ in t:l~f~c. ~ou~hn~ nd rela~ive ~re~, of sample piece~ we~d ro~lde~ for ~estir~ f inite~e~ of the ~Ine~en ~a tern. With thes~
samples piece~. r~cognitlo~ te~ w~ perfor~dt In the ~eco~nikion tes~. three te~t~r havin~ ht o~ 0 t:~
1~ ~ per~ormed the te~ ~o see wheth~r th~ ~ne~7en pAt~rn formed Oll r:e~pective s~ple piece c~n he fe~o~nl~d or notl Llnder a ~00 lux o~ ~llumina~lon ~ncl ~t a dist~nc~
o~ 30 c~ rom ~he ~mple piece~.
T~le re~u~ ~f ~h2 ~eco~nition te ~ hown ln tS Fig, lS, In ~ly. IS~ ~he ~e~tical ~xis repfe~en~ khe ~el:tive area ~ of ~he un~ven dot~ and ~he hori~ont~l ~x~s repre~ent~ the urf~oe ro~hnes~ R~ of ~h~ gerleral sur~ace 6eotion. In a~cli~ion~ the slgn ~ indicates ~h~t all ~hree ~ster re~ogni~di th~ n ~ indi~r~te~ thilt 7~ two among three ~e~ter~ reco~n~i3ed and x indi~te~ tha~
non o~ t~tex reco~nized.
In the eXperimen~s~ in c~se ~ the ~e~t1 on b~
non o~ ~he ~es~er C~uld reCogni~e th~ UneYerl p~ rn~ Oh th~ other hand, in caf~e o~ thl~ seotior c ~d the ~e~tion ~. sub~tantially the ~ f~iult~ wer~ o~'cained, There~ore~ only re ~ o~t~lned with re~pe~t ~c~ the ~e~ n c i~ shown ln Fl~ From ~he r~sult ~
illu~ .ted, 1~ i~ appreçiat~d ~h~ wherl ~h~ r~la~ive area T~ is ~rea~er than or equ~l to 3~ ~nd ~h~ f~ce rou~hne~ Ra o~ ~he ~enPr~1 ~ur~ce se~tion ~s lo~er th~n or e~u~ o O . 04 ~lm, r~o~.~it~ on of ~h~ dulled sect:lon on which ~he uneven p~ rn i~ f~rme~ uld ~e m~e. It i9 ~urthe~ appreci~ted tha~ b~tte~ re~o~nl~ion C~uld ~e ~t~ined when the rel~ti~e ~a ~ is ~rea~e~
th~n Or equal ~o 30~ ~nd th~ ~u~ace roughn~ss ~a of the yene~ u~fa~ tion ~ lo~er ~h~n o~ equal ~o 0~0~

3200~2 m Ano~her experim~nt wa performe~ trlg ~nple piece~ which wer~ provide~ Se't:ion ~or-gQed wlth wne~enes~ p~tern in a width of ~Y, a~ ~hown ~n F1 ~; Check wa~; pe~forme~ wh~ h~r the uneven ~t~n ~ould ~
reco~ d or not. ~ o~ ar~l w~ of -~he ~e~tion Wh~re r,o une~en~s~ w~s formed and ~re~ of the s~c~ion where ~me~en p~tte~n w~ ~o~n~e~ we-~ equal. M~tho~
~udge~nent w~s ~u~an~ially the ~ e ~ that irl lth~
~ormer ~st.
rrhe ~rea r~tio of the ar~ oc~upi~d ~ th~
une~eneS~ in ~he dulled ~ ion wa~ 30~ ~nd the ~urf~e roa~hn~ o~ ~he ~enex~1 sectlon whe~e unevene~ no~
~o~med, w~ 0 .40 ,~ The ~esult of the recoynition tes~
perf c~med under the ~or~goir~g cond~'cio~ is shown in ~h ~pp~nd~d ~ble 1 ~ A~ ~een ~ r~m the ~ppen~e~ ta~
when the wid~h of ~he general ~P~tlon in~e~po~l ~ioned between th~ ~ul~ed ~ectlon~ r~a~er than or eq~ to 1 ~un, Ziull~d ~ction could be re~ogni~ed.
;~;, EX.~P~pI,E:
For experiment~tlon. d~lllin~ t~ea~nt w~
per:Eormed ~or the temper roll, which h~s ur:eaçe roughne~æ Ra ~ 0.0~ ~um ~n the ~eneral ~atlon. ~h~ucJh dullin~ oper~.ti~n, uneven p~ rn to be tran~fer~d to 2~ the met~l plate w~ ~o~med o~ the per~pher~l ~u~:~aç~.
The uneven pa~ter~ was con~tituted ~ A plur~llty o:E
impre~Bion havirlg di~m~ter o~ l~o ~Im an~ pi~ch o~ ~40 ,um bet~en adjaqent lJnpre~ion~. Are~ ~tio o~ t:he area ~CCUpl~d .~y ~he lrl)p~essioll~ in ~he dull~d ~ec~o~ ~as ~0.6~, Th~, unev~n p~tS:~rn ~ormsod ~n the t~mpçr roll 1 ~howrl in E`ig ~ 17, 1~ ~d ~
~ h~ t~mpe~ roll pr~p~ ~d ~ ahoveJ was ~e~ in a ~i~nal ~tand o~ doubl~-atand ~emper rallin~ mill~
Temper ~ollin~ wa3 ~h~n p~r~ormed ~or ~ ~teel c~il o~
~he ~;lze 0~2~ X 794 ~ t: ~ redua~iun oE l.~qo. Uneven P~te~n t~n~f e~ r~e wa~ ~ 8~ . Th~ un~v~il dot f ormed on 1320a~2 the steel coil through ~he ~emper roll in~ pr~e~ haci ~urf~ce rou~hne~ ~a ~ 7.~ m. A~t*r temper rolling proce~, the co~l wa~ sep~r2~1:ed iA~ 70 plec~s. O~e of t:he piec~ w~ ~her~afte~ p~s~c~ ln pl~tin~ to make ~n ~lec~olytic tin pla~eo~or t~e ol:h~r piece~ chromium pl~ing was ~rformed ~o make an el~ctrolytlc chromium pl~ o;~ 130 mg/m~. In ~lther c2~eJ clear uneven patter~ could ~e r~o~niz~d a~e~
pla~in~ proces~.
~XhP~PL
Ei'or ~he ~emper ro~l h~vin~ ~urrAce roughne~
o:~ O 05 llm, gr~inin~ un~ven p~ttPrn wa3 ~orn~ed, whi~h unev~n p~tte~ ~a~; constltu~d ~y imp~e~ion~ of dl ~metri~al ~i%e of 10 ~o 300 llm~ ~he ~e~nper rol~
~ormed with the ~ralnin~ unetTen pattern i3 shown ln rld ~1 .
The gr3ining uneven p~t~rrl wa~ formed }~y non~ e~ nes de~ined k~y impre~ioa~s arFanged along the lin~ with ~xe~ r~tio o~ g~ The di~;t~n~e ~e~wee ~he line~ are ~et ~e~ter th~n or ~u~l to 1 ~m.
q!he tempex ~oll thu~ prepared w~ ~e~ in a 5~n~1e ~tRnd ~emper rollin~ mlll for ~erforming temper ro~ n~ ~c~r anneale~ ~t~inle~s ~keel ~ ~US~O~ with ~r~
o:~ l,o~. O~rving the re~ultant patt~r~ed ~ainl~s 2~ ~eel pl~e~ no defe~ in th~ tran~e~d ~r~ lng uneven pattern at ~e ~ur~ace 3ilde! and the ~everse ~r ba~k side ~ur~ac~ ~as m~int~ine~ ~ubst~ntially pl~
Fur~hermore~ a~ ~b~r~d, th~ ~r~inin~ patt~rn ~or~ed on ~he su~:f~e ~ th~ st~inle~s ~eel plate w~ de~nl~:e.
~PA~T;C~E ~MPJ3E3 In ord~r ~ ~ompare with thq p?.~te~n~d plate~
m~de through ~he pre~erre~ emhodimen~s, comp~rati~e exp~rim~tæ were per:~ormed, I~ the compar~ive ~x~mple 1~ ~.emper rollln~ ~a pe~f~rmed ~ mean~ 4~ ~he tem~?er 11 which wa~ dull~d ~h~ough the ~onv~ntio~l p~oto-et~hiny proce~ In thi~ c~, unl~ he - 2~ ~ 132~)~22 impre~ion h~ving dept.h deel?~r th~sl 100 ~;m~ l:h~ tlneve~
patt~rn to be ~r~n~f erre~ on~o th~ ~teel pl ~te whl~h i~
identlcal to tha~ u~ed in the f~r~going ex~mp.1e :l. w~
no def ini~:~. In ~ddition, ~na~her ex~erimen~ w~s per~ormed hy utili~ g em~o~ t~h~ ~nto th~
outer ~riphery ~f 1:h~ ~cemper roll, ~hlch eTn~ s f il;~
wa~ ~rmed ~i~h ~ripe une~en pat~er ~ 4wn in Fig3.
17, ~ ~ and 1~ . In this ~aæe~ due to roll ourYe~ the ~trip~ transfe~red onto the ~teel 8t~1p ~OU~I~ no~
~traight~ ~
For m~k lng comparativ e s~mple~ ~h~ ~empe r xoll with th~ ~nev~n pattern ~on~itu~e~ ~ ~ plur~l ity o~
i3n~re~sion~ e~h of whi~h h~d ~epth of 1~.0 ,~ h ~h~ temper roll, temper rollln~ was peL~or~e~ ~or thc m~eri~ ee~ ~tr~p ~me ~ tha~ u~ed in ~he fore~oing ex~mple 1 wa~ Ferfor~ne~ in sub~n~i~lly th~ e proces~ The re~ul.~nt ~t~el plat~ ha~ lln~ve~e~; o~ the back 8ide. In add~tlon~ the un~ven pattern ~r~n~f~rr~d on -th~ ~3ur~ce ~de w~s not s~tl~ ctorily d~f ~nite, ~ARA~n~ PLl3 ~
In order to comp~re wlth the f oregoin~ ex~mple ~ I the tempe~ roll ~ith grainin0 un~Ten p~ e~n s7~;
prep~re~lJ which ~rainin~ une~YPn p~ttern wa~ ~ormed ~
photo- etchin~ prw.e~ ~o h~ve dep~h ~f l~O llm in each lmpres~ion. ~he non- lin~r 1ine~ in ~he grainin~ ~In~7en pa~ern formed on ~he ~emp~r ~oll projec~ f~om the ~el~er~l ~urfa~e. -l~ef~ct in 1 in~ clr 1lnes for~niny th~ gr~ 1n~pattern w~ ol~served ~f~er rollirlg of stainle~ strip in ~ len~th o~ ~ ~m. F~rthermor~ che inltlal ~t~9~ of t~mper roll ing. une~en~ w~ f orm~d eve~ ~t th~ ~ck ~ide of the pl~te.
~ will b~ cl~ rom ~h~s~ ~he me~l plate Wi~h ~he uneY&~ patte~n Eormed ~c~rdin~ the pref erre~
pr~ces~ r~inr~ to the pre~ent invention c~n e~shi~it ~xceller~t ~ppeaJ:ance wlth h~h corrosion re~ist~n~e an~

-- ~7 --~32~22 w~ th~ re~ an~e .
In ~a~e o~ ~h~ m~ 11 ten per r~11 in~ mill, th~ uneven patterrl on ~he work xoll ~nd~: to be ~ran~erre~ Orl ~he p~ripher~l ~urf~ce of a b~ck-up ~o~ l ~I/or 2n interm~dia~ce rsll ~ihce ~he kack-up roll is p~e~sed vn~o ~he p~lp~e~l surf~ce of the w~rk ~
Wh~n ~he work roll 1~ ch~nged for ch~ngln~ the uneven pat~erll to ~e form~d on the ~t~l ~tri~ the uneven p~ttern ~med on ~-h~ k-up roll And~or th~
ln~ermedia~ roll i~ transf e~red to th~ work roll thr~u~h th~ temper rollin~ p~oc~ to oYerl~p with th~
~e~ired uneven p~ ~ern. Thi~ overlapping un~ven pattern wlll be ~ran~ferr~d f rom ~h~ work ~oll t~ the metal ~trip to ~egrad~ th~ qual i~y o~ the ~neven pal:~erned ts me~ rlp ~nd ~h~ appe~ancc ~here~f~
In order to a~oid thi~ ~}rindin~ proce~s ;s performed fo~ the ~a~k-up roll and~or the in~ermedia~
roll for rem~vin~ the ~ur~ace portloIl or o~lter skin po~tion of ~he roll~ ~y Ine~ns o~ sand-pap@r. ~7h~ one and ~o forth. ~u~iny this grindln~ pro~ess, th~ temper roll inS~ ~nill i8 ne~é~rily stopped. This ~ppa~n~l~
lower e~'~iciency. I~ addition. wh~n the un~v~ne~ on ~h~ perlph~ral ~ur~es of ~he ~ack-up roll ~n~or the in~e~medi~te roll ~r~ rel~tively deep9 ~he Llneve~
2~i po~ti~n on the ~urf ~c~ o~ the ~oll s canno~ he r~mov~cï
~o~npletely even b~y the ~rindil~ proc~s~.
The pr~sent~ ven~1 on addi~ionally prov id~ ~
me~hOd an~ ~pp~x~tu~ or ~voiding the - ~foremen~ d d~feo~ nd thu~ ~o~: maint~ a~lsfa~to~ily high . 30 ~ ien~y ~nd high yiel~ in pr~du~;ion o~
s~ti~~ctorily hlgh ~u~lity pat~e~d me~1 3~rip or pl The p~e~rred ~ml~odimen~ o a ~mper roll in~
mill sui~ab~ ~or impl~mentln~ the p~e~er~d proce~ o~
tempe~ r~l~ ing a~co~dlng ~o the pre~ent inven~ion~ will b~ discu~sed he~e~eloY wi~h ~e~e~enc~ to ~ig~, ~2 ~o ~gD

.

- ~.R - ~ 3200~2 Fig . 7 ~ ~how~ ~h~ iE irst embo~lmen-'c o~
four-roll type tem~r rollin~ m~11 -to impl~m~nt the pref~rred pro~e~ for ~o m~n~ th~ uneven p~t~ern on the ~n~tal ~crlp.
The ~ollx-st~nd l:ype tempe~ rolling mil1 comprisas ~h~ wor~ roll ~ loO which 1~ form~ with the uneven p~ttern t~r~h th~ r dull ing p~oce~ a~
fort~ a~o~re~ In the ~how~ embodlment/ tne ~ e ImeYen pattern havln~ a plura~i~y of ~tripe l Jlnes extending aircum~elie~tially, i~ ~o~ne~ on the work ~oll ~urfRce~
The stxipe lln~s are ~m~ $n par~llel t~ ea~h o~her ~n~, sp~ced ~y from ~he ~d~cent str~pe lines with a ~ven ~istance }:~ ~n. Th~ temp~r roll ing mlll al~o h~ a h~ck-up roll~; 102 which provide back pres~ur~ for respectively c:orre~;pondiny work roll~ Th~ work rQll~
loo aI~e ~sgocia~ed with ~draulic cylind~r 104. Th~
hyd~auIia ~rlin~ers 104 ~re . respe~ i~ely de~i~ned ~o ~r~ve ~.he correspondin~ work r~ lo~ ln axl~l ~ire~tion. The shl~tin~ m~gn:;~ude a n~n oiE ~he work roll ;20 loo is ~o ~3el~ed as ~ greater thall or ~q~
h~lf of t.he dl~tanc2 b mrn ~e~ween the s~r~p~ line~, ea~h which 1~ :Eo~med by th~ ~ul:Led sec~ion.
The hydr~ul ic c~inl~e~s 104 are cycl ic~lly ~nd ~ynchr~n~usly driv~n f or cau~in~ ~xial shi~t ~ a 2S predetermin~d di~ ce~ In the alt~rnati~. lt ~ e ~s~lb~ e t~ ~on~inuou~ly drive th~ work roll f~r ~xial ~h~tln~ ~
I~ the work rc~11 lQo i~ no- shi~ ed in axi~l dlr~ction th~ouyhou~ ~he t~m~er roll ing m~ll ope~a~ion~
q'he unev~n ~ripe pattern i~ tra~f~rred vnto the ~ack-u~ ~411 ~ir~c~ t:hr~u~h the ~emper r~
per~ iOn, ~l6~ ~own in Fig. ~3. On the o~h~r hand, 1~y ~;xial sh~tin~ o~ ~he work xoll loV r~l~tive ~o th~
back-up ro~. the r~la~iv~ly ~ld~ ran~e of d~pr~sed ~ectiOn 10~orm~d ~n th~ k-up roll~ hot~n in . Fiy~hi~ make~ ~ the d~pth o~er ~h~ ~epx~s~d .
,.

..... ..

- 2~ - ~320022 Be4tion 10~ ~u~ nt:ially even. Therefo~e~ i~ hecom~
unne~e~ r~ t~ pel ~orm ~rin~ing pr~e~;s even wh~n ~he woxk ro~ chtlnge~l. -In the pre~rre~ pro~e~s~ the hydraulic~llnder 104 i ~o~nected to ~ p~ssuri~ workl~ f1~ d ~3Ource via ~ pres~ur~ line 108~ A thre~ y f~ow COn~rol v~l~7e :110 may b~ pro~rided in the pre~ure line lo# ~r ad~us~;in~3 the ~luld pre~u~e for ~ri~ing the Work roll lOo ln ~he axi~l direction- The drl~re. ~peed o~ the hy~lraulic ~linder 10~ in ~x~al ~lrec~ion i~
su~stanti~lly lc~er in ~omparison with ~he line 5peed 0~
t} e m~t~l ~trip. For in~-an~e~ the sp~d o~ ax~ 1 ~:hi~n~ Oe th~ work roll is ~o ~el~ted ~ to ~e bou~
~llooo of t}~ç line ~peed, The~ef~re, ~h~ off~et o:~ the t~ipe lin~; of tha uneven pattern form~d on the met~l ~trip i.~ not notic~ble, Cc; n~#~uen~ly, the hy~ ul lc C~linde~ 104 i~ drive~ cont1nuo~ly to co~lnuou~ly ~hi~tin~ the wo;ck roll in ælxi~l direction.
~he hi:etin~ magnil:~ude ~ mm oE the work r411 ~G 1(~0 1~; neG~3~.rlly gre~ter ~ n the ~xial wi~th h mm of th~ lnter~ l b~tween stripe î in~s. When ~h~ ~hif ~ing ma~ni~ude ~ mm is ~m~ller than h~lf o~ the wid~h b mm of th~ inter~ non-de~rm4d ~b~ion 11~ in ~ wid~h ~ mln ~læ t mm~ will ~ em~lnçd~ as ~h~tn ln Fig ~
2 ~1A). Thl~ UneY~n pæLt~rn tend6 ~0 be tran~ferr~d ~o ~he work roll. ~n thi~ viewJ ~o a~ ~o mRintaln ~he p~Lipheral ~ur~e of the wo~k roll ~ub~n~l~lly ev~n ~y uni~mly ~lep e~lng th~ ~ver~ r~ s ~hown i~
Fi~, 2~ h~3 shlft~ing ffln~an:itUd~ a mm of axi~l ahi:E~
3p n~ ~he wPrk r~ll 10~ mUs~ be great~r than bl2 mrn~
In order to ~f ~ct ~f axial ~hif ~iny ~ ~h~
w~k ~oll in v i~ o~ m~ n~nanca of ~he l~k-up r~ll ~d~or the interm~ te r~ll, ex}?erilnen~ w~re p~rformed util i~ing double-~t~n~ type temp~r rolling mill with the 7~ hyd~uli~ w~rk roll ~}lifting d~vloe ~s ~t ~or-th ab~
. As ~ No, 1 s~nd roll~ p~ane surFa~e hri~ht roll h~vin~

- ~o ~- ~320~22 ~urface rou~hneæ~ of o.l~ t~ 0,1 B ~ a3 us~d~
Mo. 2 ~tand roll . ~h~ wo~k roll with l~er du~l~d un~ven ~tt~rn ~7as u~ed. ~ernp~r roll in~ wa~ perf ormed in dr~t of 0.~ ~ 0~. Th~ w~dth of ~h uneven Fltrip2 for~ed ~n the wo~!c roll w~s ~ Imn. rf~dth o~ ,.h~ ~n ~etwe~n the un~ren s~:r:i3?es were ~aried 1~ 2 ~mJ ;~
lo mm and ~5 fl~ he axial shiEtin~ ma~nl~3e o~ the ~ork roll loo wa~ ~et ~n a ma~ltu~e of ~ nun~ Th~
hydrau~ ic cylln~er 104 wa~ continuou ly driv~n to ~hr~ln~ly shift ~he work r411 ~o th~t th~ ~me~n p~tte~n formed c~n the nnetal sl~rip fortn~ ~in curY~
one cyc:le o~ thru ~ing ~hift o~ t~ work roll w~s set for lOOo m of ~he m~ 8~;~ip leng'ch. ~)n the oth~r . h~n~, the t~mper rolliny wa~ per~ormed at a l~ne ~p~ed 1~ ~ 5 0 0 mpln .
~ter temper roll in~ he ~urface ~ondi~i~n bf the ~righ~ roll ~7hi~h ~er~ed as the b~k-up roll w~
che~ked~ The re~ult o~ ol~e~r~on o~ the ba~:k-up rol~
sur~ce i~3 ~hown in the ~ppended t~le 2.
~n order, t~ compar~ the~e re~ul~. comparatl~?e expRrlmen~ w~i pe~-~orme~ to per~o~m ~empe~ roll ing wl~hout shlf tlny the w~rk roll A~ s~el~ f ~om ~he ~-ppended ta~e ~ lon~
the width ~ the ~nt~v~l b~tween the un~ven ~ripes i~
~mall~r th~n twi~ he ~a:ial ~hi~tir~ ma~tude o~
the work r~ll. QO fnRin~enanc~ wa~ requlred~ ThereEore.
when n~esæi~y o~ ~hanylng uneven pattern oc~ur~
~x ~ ndin~ pro~e~æ o~ ~epl~cem~nt 4f th~ ~ck ~p roll W~t~
no~ requl~e~ When the ~x~al ~hi~ magni~ude of ~h~
work ~cll is ~m~ r ~h~n 112 ~ ~h~ wi~h of the ~nterval o~ the un~ven ~trlp~ rind~ ng p~o~e~s wa~
Fequire~ remo~e l:he non-d~pr~ssed pr~ ectin~ ~e~tivn~
~or m~k~ th~ k-up roll sur~a~e ~ubstantl~lly even. ~)n h~ other hand. when ~he work roll i~ no~ ~hl~ta~, 3~; repl~cement o~ the b~k-up roll w~ neces~ar~7 when . ~hanging .he w~rk ro~l h~ving di~eren~ uneven patter;t ...... "" " ",, ,,, = ~

''"'''' -~ , ~

'~ ' -:

~32~)022 to the f orm~r one .
Fl ~. 2fi show~ ~oth~ em~o~imen~ o~ ~he temper roll lng mlll to implem~ he p~e~erred 'r:empe~ rolling proce~ a~ordln~ to ~h~ present in~en~lon. The ~hows~
em~Od.imeIIt i~3 dlr~ted to ~lx~roll tv~ te~*r rollin~
mil 1 in~l~ding ~ p~ir of work roll3 ~ QO ~ . p~ o~
back up ~oll~ 10~ 2Lnd ~ pair of in~rm~iat~ rol~ s 1~
~n ~hl~ emb~dim~n~, th~ hyd~l ic ~ylinder~ 104 ~e a~sc)~iAted with th~ int~r~nedi~e rDll~ 114 ~o~ ~ivin~
the la~ter to c~use a~cial ~hifting.
P,~ will ~e ~ppre~i~t~d~ the unev~ p ttern on the work ~oll loo 1~ t ~ns~err2d to ~he in~erm~d;a~e roll 11~ and ~ub~e~uen 1~ e b~ck-up roll 1O2D
Ther~for~, when ~11 o~ ~h~ WDrk roll loa ~ the t~; interme~iate roll 114 and the back-up roll lo~ ~r*
maintained in f ~ed rel~:ionshlp to ea~h oth~, the uneven p~cer~æ as ~hown in Fig~ ~7 will ~e rormed on the lT~erme~ e roll 11~ ~nd ~h~ back-up roll 104, ~n ~hi~ c~se, when th6! ~ork roll ~ ~h~n~ed ~o ~hange ~he uneyen pa~tern ~o ~e fo~med on the meta} ~trlp~ th~
uneven pattern on the h~ck-up roll 104 2lnd ~he in~erme~i~te eoll 114 1~ neo6~ ily tran~erre~ ~o the Work ro~l . The~ef ore, th~ un~ven pattern o~ the ~ormer Wo~k ~oll overl~ps with ~he d~ired u~even patte~n o~
th6~ cure~:nt work roll. This ~ppArantly deyr~de the aPp~ n~ of th~ met~ te to be forlt~ed~
~hi~ de~ect ~an be ~limlnated b~ hi~lng one 0~ the ~o~k ro}l ~nd ~h~ in~ermedi~te r~ll in axial direction ~ ~nake th~ ~Ate ~ fo~m~ion of uneYen~s on 3~ ~h~ interme~iat~ roll ~n~ b~qk up r~ll even thr~ugh ~vera~ 1 periphery. ~ ly, ~ ~hiiEting t~e i~rsrediat~
rc~ 14, ~h~ u~eY~ness ~o ~e formed on the in~ermed~te roll b~omes at ~3u~ nti~lly e~ven hei~ht through ov~rall ~ur~ace, a~ shown in ~ his unev~ne~
;~ tra~erred ~ the ~back-up ro~l to t~a~ r ~he un~Yen . p~ttern. Ther~for~ nce the in~ecm~di~e xoll ~u~f aCQ

.

320~22 Rnd the hack-up ~oll surf~e are m~ln~ ed sub~an~l~lly plane, yrin~ g px~ or ~ pla~e~Qt o~
the hack up roll ~nd/or the inteLmedl~ oll upon ~har~gin~ of the une~en p~ttern to form on l:he me~l 1p, ~ecome~ unneoes. ary~
Si.mil~rly to -the fo~es~ m~dime~, ~e hif t1 n~ ma~ni~ude ~ ~rL of the in~err~ te r~
n~ce~arl:ly ~reater ~han th~ axial ~ h ~3 nm of the lnte~val between ~tripe 1~ n~. Wh~n the ~hi~in~
lU magnltude 3 mm i~ sm~ r th~n hal~ o~ ~h~ width b mln of th~ inte~v~l, non~deform~d sec~lon 112 in ~ width c mm ~hl~mm) ~ atmm~ ) ~ill be remained. ~ ~h~n ~n Fi~.
~ ~a~ ~ ~rhi~ unev~n pat~P~n tend~ ~o ~e tr~n~err~d ~o the work r~ll. In th~ Yi~W~ ~0 a~ ~o ~n~intaill th pe~iph~2~al sur~ace ~f ~he inte~m~diat~ roll sub~ nti~lly ~Yen by uni ~ormly d~pre~in~ the o~erall are~, as shown irl ~iy~ ~(b~ . the ~hlftin~ m~L~n$tU~
mIn u~ a:~ial ~hi-~ of ~he in~:e:rmedi~t~ ro~ 1 114 must ~e gr eater th~n b/ 2 mm~
In or~er to ef:~ect ~ ~xlal shif~lng o-~ the in~ermedi~te ~ol l in view o m~intenanqe of the b~k-up roll andior the interme~iate ~ experlment~ wefe pe rf ~rmed ut ~ l læ ing dou~l e- sta nd ~ype tempe r r ol l ing mill with $h~ hy~rElulic int~rme~iate roll ~hiftlng evlce ~ se~ Eor~h above~ A~ ~ ~o. 1 ~t~nd roll, plane ~ur~ace bri~}~'c rnll having ~urface rouyhn~ o~ 0~ t~
0.1~ 1 ~1 WAI~ u~d- A~ a No~ ~ ~t~nd ~oll, the wo~k roll ~ith l~er dull~d un~3v~r~ patte~n wa~ use~. Temp~r r~lling wa~` perorm~ ~n ~ dr~t o 0.~ The Width o~ e~cb uneven ~tripe ~oxMe~ on the wo~X roll was so S llun. Wid~h of th~ in~ al be~w~en the uneven stripe~
wer~ ~ried in ~ n m~n ~nd ~ 5 ~un. Th~ axial Shl~ting magnltude o~ th~ in-~rme~ t~ roll 11 4 wa~ ~et irl a ma~nit~de of ~ mm. ~h~ h~draulic ~1 lnd~ 4 w~
;~ Con~inuo~ly ~iven to ~hrust:lngly shi~ th~
irlterm~diate r~ o h~t ~he un~ven patt~rn form~d on ... . ~

- 33 ~.320022 the met~l strip ~orm~ ~in curve. The on~ cy~e o~
thru~tin~ ~h~t of he ~nter~n~di~te roll w~ ~et ~or ~0 m o~ ~he me~ trip len~h~ C)n ~he other hand. ~he t~mper rolll~ Wi~18 E;erforme~ ~t a line speed of ~0 mpm.
A~r ~em~e~ r~llln~, the ~urf a~e coFId~ 4n or the bri~ht rol~s w~ch served ~ the ~ack-up roli zn~
the intermed~a~e r~ll were che~ d. ~he re~u1~ of ob~3erv~ n o~ ~he b~ck-up roll ~u~f ~ce 1~ ~hown 1 n ~h~
~ppended t~bl e ~ .
Irl o~er to comp~r~ the~e r~sult~ compar~ e expef imen~ wa~ per~ormed to per~orm ~empe~ ro~ 1 in~
w lthout shif tin~ the in~e~medi~te roll .
A~ s~n f rom the ~pp~?n~d ~hl e 3, as l ong the wldth o~ ~he ln~erv~l ~e w~n ~he un~7en ~tri~es i~
~maller th~n twice of the ~xl~l ~hi~.lng Tn~ni tude ~f the intermedi~te roll, no ~intenan~e w~ re~uirPd, There~ore, wh~n nece~ ty o~ ~han~lng uneven p~t~ern o~cur~, ~rindin~ pro~e~ or re~laaemen~ Qf ~he b~ck-up ro~l was no~ requ.~red. Wh~n the ~xi~l shiftin~
2a ma~n~ tude o~ ~he in~ermediat~ roll i~ ller ~h~n lf of th~ wid~h o~ the interval Pf th~ uneven ~t~ipes.
qrin~inrd proce~x wa~ r~ui~ed ~o remove the non~d~p~esSed pro~ectin~ ~eetion~ or m~Lke the ~ack-uF
oll ~u~f ace sul~an~ ly e~en. On ~h~ o~her h~nd, ~; whe~ ~h~ in~e~medi~t~ roll i~ not shlf~edl rQpla~elnent o~ the ~a::k~tlp rvll wa~ n~ce~ rY wh4n changin~ ~h~ s~o~k roll hav~n~ di~eren~ une~n pa~xn to ~he ~ormer one.
A~ wi~l ~e ~een h~r~ r~m, ~h~ t~mpe~ ~vll ing mill ac~ordin~ ~o the pre~en~ in rention, p~o~i~e ea~y ~O - maint~nance o.E the interm~diate roll ~nd ~he back-up r~ nd exp~nd th~ e of the roll ~ln~e no ~inding proce~;s ma~ ~e pe~ormed or 1~3~g dur~tion~
~hil~ the pre~en~ ln~ten~ion h~ ~een di3clo~ed in term~; of the preferred embodlmen~ in o~d~r ~o 3~ cilit~te ~et~r ~nder~tandln~ o~ the lnvention. t should ~e appr~cl~e~ th~t the in~en~ion can be em~udiec~

~ 34~ ~32~022 in vario~l~; way~ wi~hout de~lrtln~ f r~ he princip:l~ of -the inventi~n. The~er~or~, thP inv4~lon ~houl~ ~e under~tood Jco ;in~lude all po~ible ~m~odiments an~
modif ication~ to the æhown ~m~odiments wh~c~h ~n b~
~ml~odie~ without dep~rting ~ ~o~ the prlncipl~ o~ the in~ ~n~ ~ on cet o~lt i n the ~ppe ~de~

1~

~0 , .
. , :' . , : :
.
' ~ 35 ~
T~L~ 1320022 . , __ _ .................. _ . __ _ ~
~ult X ~ ~ ~ C~ ~
~ ._ ~ ~ ~_ ~ . _ .
m~_I) _~ ~ 4 ~ ~ 0 8 1.0 I a 1.

TA~ æ
. ~ . . .~
W~rk Roll A m~ ~ mm b/2 mm l;J~rer~n~3 Tr~f~rr~d __ . . . __~ _ ~ _ ~ S 2 1 I~i~h~ (M~ten~ no~ r~qu~rqd~
....~,, _ . _ ._ ~
~h~ ~ ~ ~.~ I.ight (~ te~ance notr~qu~a~
_ , ._ _ . . . __ _ ~
Shi~t ~ 10 ~ ~ight ~M~int~n~ce not requir~d~
_ ,__ _ ~
5~ift ~ 1~ 7.~ ~ninl:~n~nce l e~u~red . _ _ _...... . . ........ ______ Not ~hif~ ~ ~ ~ _ 2.~ ~loll repl~m~nt l~e~irod - - - . . . - - ~ - . . .
Shif~ of ~ mm b mm b/2 mm IJneYens~3 Tran~fe~red lrltermedi~t~ ~11 __ _,_ ~_ ._ . _ _~
Shl~ ~ ~ 1 I~Ight IM~int~nD.rl~ no~ req~ d) __, __ . . _~ _ _~
Shlf~ ~; ~ 2.fi Light thf~ntan~n~ no~ requlr~d) .. __ _ _. _ _ ,_ _ _ _ !3h~f~ ~; 10 B Ligh~ ~M~ntun~d not re~uir~d) ~ _ ..... ~
Shf:f~ ~ 1~ 7.~ ~al~t;en~ncc raquir~d ~ _ .~
Not 8hif~ .__ - __ _ .5 _ a.~ ~
I .

Claims (33)

1. An uneven patterned metal plate having a surface, on which uneven pattern is formed by at least one pattern unit constituted by a plurality of uneven dots, each of which has a size D, said uneven dots being arranged in a predetermined density to have given ratio ? of occupying area versus plane area in said pattern unit, said size D and area ratio ? being in a range of:

10 ? D ? 300 (µm) 30 ? ? ? 100 (%) and the size of said pattern unit has minimum length of 1 mm.

2. An uneven patterned metal plate having a surface, on which a visual decorative uneven pattern is formed by at least one pattern unit, said plate having a plurality of pattern units, said pattern units being separated from each other by unpatterned plane areas free of uneven patterns, each of said pattern units being constituted by and with a plurality of uneven dots, each of which has a size D, said uneven dots being arranged in a predetermined density to have a given ratio ? of the occupied area versus the plane area in said pattern unit, said plane area having a surface roughness Ra which is equal to or less than 40 µm, said size D and area ratio ? being in the range of:
10 ? D ? 300 (µm) 30 ? ? ? 100 (%) and wherein the size of said pattern unit has a minimum axial length or width equal to or greater than 1 mm.

3. An uneven patterned metal plate as set forth in claim 2, wherein said pattern unit is in the form of a line having a width greater than or equal to 1 mm. and said pattern unit is spaced from the next pattern unit at a distance equal to or greater than 1 mm.

4. An uneven patterned metal plate having a substantially flat surface provided with a specially patterned plane area, the surface of said plane area being modified by the presence of a multiplicity of spaced-apart impressions formed in said plate and arranged in groups in accordance with a predetermined pattern and at a predetermined density on said substantially flat surface, said impressions being positioned between plane areas and including peak portions which extend beyond said substantially flat surface and depressed portions which extend within said plate beneath said substantially flat surface, - said impressions having a size D which is the dimension of said peak portion and which is in the range of 10 to 300 µm, - said impressions having a surface occupation density which is the ratio of plate surface area occupied by said impressions to surface area unoccupied by said impressions, and which is 30-100%, - said patterned groups having minimum lengths and widths in the range of 1 mm or greater.

5. An uneven patterned metal plate as set forth in claim 1, wherein the surface roughness Ra of said plane area is smaller than or equal to 0.40 µm.

6. An uneven patterned metal plate as set forth in claim 1, wherein each of said uneven dots is formed into essentially circular configuration having said predetermined diameter of D.

7. An uneven patterned metal plate as set forth in claim 1, wherein said pattern unit has a width greater than or equal to 1 mm.

8. An uneven patterned metal plate as set forth in claim 1, wherein said pattern unit has an axial length greater than or equal to 1 mm.

9. An uneven patterned metal plate as set forth in claim 1, wherein said uneven dots are formed on said metal plate through a temper rolling process by means of a dulled work roll on which uneven pattern corresponding to the uneven pattern to be formed on said metal plate is formed.

10. An uneven patterned metal plate as set forth in claim 1, wherein said uneven dots are formed on said metal plate through a temper rolling process by means of a dulled work roll on which uneven pattern corresponding to the uneven pattern to be formed on said metal plate is formed, and wherein said dulling operation is performed by means of high energy beam.

11. An uneven patterned metal plate as set forth in claim 1, wherein said pattern unit is in a form of a line having a width greater than or equal to 1 mm.

12. An uneven patterned metal plate as set forth in claim 1, wherein said pattern unit is in a form of line having a weight greater than or equal to 1 mm and wherein said pattern unit in a form of line is distanced from the next pattern unit in a distance greater than or equal to 1 mm.

13. An uneven patterned metal plate as set forth in claim 1, wherein said metal plate is formed with a plat-ing layer on said surface.

14. An uneven patterned metal plate as set forth in claim 13, wherein said plating layer has a thickness thicker at the projecting peak portion of each uneven dot than that at the depressed portion of each even dot,

15. A laminated patterned metal plate, the surface of which includes flat areas and a multiplicity of impressions arranged in groups in accordance with a predetermined geometric pattern on the surface of said plate, - said impressions including raised portions and depressed portions extending respectively outwardly and inwardly of said flat areas, and - a surface lamination applied to said plate surface, said lamination being thicker at said flat areas than in said depressions.

16. The patterned metal plate defined in claim 15, wherein said surface lamination is a metal.

17. The patterned metal plate defined in claim 15, wherein said surface lamination is a resin coating layer.

18. The patterned metal plate defined in claim 15, wherein said surface lamination is also thicker at said raised portions than at said flat areas.

19. A process for forming uneven pattern on a metal strip comprising the steps of:
- providing a work roll for temper rolling having a surface roughness Ra smaller than or equal to 0.40 µm;
- performing dulling operation for forming desired uneven pattern to be formed on said metal strip, which uneven pattern is formed by at least one pattern unit constituted by a plurality of uneven dots, each of which has a size D, said uneven dots being arranged in a predetermined density to have given ratio ? of occupying area versus plane area in said pattern unit, said size D and area ratio ?
being in a range of:

10 ? D ? 300 (µm) 30 ? ? ? 100 (%) and the size of said pattern unit has minimum length of 1 mm;
- setting the dulled work roll in a temper rolling mill and performing temper rolling and transferring said uneven pattern onto the surface of said metal strip.

20. In a process for forming a metal plate having a substantially flat surface provided with a specially patterned plane area, the steps which comprise dulling to the surface of said plane area a multiplicity of spaced-apart impressions formed in said plate and arranged in groups in accordance with a predetermined pattern and at a predetermined density on said substantially flat surface, said dulling being applied by a temper roll having a surface roughness Ra equal to or less than 0.40 µm, said impressions being positioned between plane areas and including peak portions which extend beyond said substantially flat surface and depressed portions which extend within said plate beneath said substantially flat surface, - said impressions having a size D which is the dimension of said peak portion and which is in the range of 10 to 300 µm, - said impressions having a surface occupation density which is the ratio of plate surface area occupied by said impressions to surface area unoccupied by said impressions, and which is 30-100%, - said patterned groups having minimum lengths and widths in the range of 1 mm or greater, and transferring the spaced-apart impressions to the surface of said metal plate.

21. A process as set forth in claim 19, wherein said dulling operation for forming uneven dots constituting said uneven pattern is performed by means of high density energy beam.

22. A process as set forth in claim 19, wherein said dulling operation for forming uneven dots constituting said uneven pattern is performed by means of high density energy beam, and wherein said dulling operation is performed by means of a laser beam.

23. A process as set forth in claim 19 or 20, wherein said surface roughness Ra is smaller than or equal to 0.40 µm.

24. A process as set forth in claim 19, wherein each of said uneven dots is formed into essentially circular configuration having said predetermined diameter of D.

25. A process as set forth in claim 19, wherein said pattern unit has a width greater than or equal to 1 mm.

26. A process as set forth in claim 19, wherein said pattern unit has an axial length greater than or equal to 1 mm.

27. A process as set forth in claim 19, wherein said uneven dots are formed on said metal strip through the temper rolling performed in said temper rolling mill by means of the dulled work roll on which uneven pattern corresponding to the uneven pattern to be formed on said metal strip is formed.

28. A process as set forth in claim 27, wherein said dulling operation is performed by means of high energy beam.

29. A process as set forth in claim 19, wherein said pattern unit is in the form of a line having a width greater than or equal to 1 mm.

30. A process as set forth in claim 29, wherein one of said pattern units is distanced from the adjacent one of said units greater than or equal to 1 mm.

31. A process as set forth in claim 19, wherein said metal strip is formed with a plating layer.

32. A process as set forth in claim 31, wherein said plating layer has a thickner thickness at the projecting peak portion of each uneven dot than that at the depressed portion of each even dot.

33. A process as set forth in claim 19, wherein said temper rolling operation is performed with driving one of said work roll and a roll with plane surface and contacting with said work roll to cause relative shift in axial direction