Note: Descriptions are shown in the official language in which they were submitted.
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COMPOSITION AND PROCESS FOR TREATING METAL
5 BACKGROUND OF THE INVENTION
Field of the Invention
This invention relates to plvcessGs of treating metal s~ s with aqueous acid-
ic compositions to increase the re~i.cf~nre to corrosion of the treated metal sllrf~ce7 ei-
10 ther as thus treated or after subsequent overcoating with some convçl-lion~l organic
based plvLG~;LivG layer. A major object of the invention is to provide a storage stable,
preferably single package, tre~tm~-nt that can be ~..hs~ ti~lly free from hexavalent
Cl~l'OllliUlll but can protect metals subst~nti~lly as well as the hexavalent Ch~'U111iU111
CO;~ g L~G~IIIIP~ ; of the prior art, or can illlprovG the stability of tre~tm~-nt solu-
15 tions that do contain hexavalent cl~.~uliu.lThis invention also relates to reaction of
fluol~ t~llic acids with other metal or m~t~ icl col~l;1ill;l-g m~tt~.ri~l~ to produce
compositions or int~rmprli~tes for compositions useful for such tre~tment~
Statement of Related Art
2 0 A very wide variety of m~t~ri~lc have been taught in the prior art for the gen-
eral purposes of the present invention, but most of them contain hexavalent Chlullliu
or other inorganic oxicli7ing agents which are envil~l....ent~lly undesirable. Also,
many of the prior art LIG;1ll11~.1l compositions include colll~ Gllt~ that are chPlni~lly
or physically lln~t~hle when mixed, so that single package concel~dLGs for such
tre~tm~nt culL~o~iLions are not practical.
DESCRIPTION OF THE INVENTION
Except in the claims and the opel,.~ eY~mple~, or where otherwise expressly
in-lir.~te-l all nnm~.rir.~l qll~ntiti-o.c in this description in-lie~ting ~11OU11L:j of m~t~.ri~l
or conditions of reaction and/or use are to be nnrlP.rstood as m~-tlifi~o.d by the word
~ 3 0 "about" in des~rihing the broadest scope of the invention. Practice within the numeri-
cal limits stated is generally ~lcre~lGd. Also, unless expressly stated to the collLlaL~;
percent, "parts of", and ratio values are by weight; the term "polymer" inr~ s
oligomer; the des~ription of a group or class of m~teri~l.c as suitable or ~erGl.cd for
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a given ~u.~ose in conn~ction witn the invention implies that ~ LulcS of any two or
more of the Illr..llh,.~.~ of the group or class are equally suitable or ~lefc~l~,d; descrip-
tion of conctitllents in ch~mi~l terms refers to the cnn~ te~ at the time of ~d~lition
to any cl mhin~tion spec-ified in the description, and does not n~cecc~rily preclude
5 c.h~mic~l interactions among the conctituentc of a llli~lulc once mixed; specific~tion
of m~feri~le in ionic form implies t'ne presence of sllfficient cuunlclions to produce
electric~l nelltr~lity for the ~;olll~o:jiLion as a whole (any co~ r.. ;nnc thus implicitly
specified should preferably be selecte.-l from among other co~ ; explicitly spec-
ified in ionic form, to the extent possible; otherwise such countclions may be freely
10 sel~cte-l, except for avoiding cuu-.l~..;c-l-.c that act adversely to the stated objects of the
invention); and the term "mole" and its variations may be applied to elem-o.nt~l, ionic,
and any other ch~mic~l species defined by nulllbel and t,vpe of atoms present, as well
as to compounds with well defined molecules.
Summar,v of the Invention
It has been found that aqueous colll~osiLions cn---l--;c;--~ (A) a colll~ollcllt of
dissolved fluoroacids of one or more metals and m.o.t~lk)i~ mr.ntc selected from the
group of ~olemPntC concicting of ti~ i.. , zi.colliu~ll, h~fninm, boron, ~l~.. i.. , sil-
icon, ~,r~ ll;lllll, and tin and, (B) a colll~on~,..t of one or more of (i) dissolved or dis-
persed finely divided forms of metals and mr.t~llc)itl elem~ntc selocte-A from the group
of el~m~.nts concicting of lil~,.i.. , ;~;OlliUl~l~ h~fnillm, boron, ~ ;n~ silicon, ger-
m~nillm, and tin and (ii) the oxides, hydroxides, and carbonates of such metals and
metalloid elem~ntc can be caused to r.hP.mi~lly interact in such a manner as to pro-
duce a co-ll~osiLion useful for novel metal L--,~lll---i-l.~ Lf cu-ll~un~"-l (B) is present in
~licpercion rather than solution, as is generally ~lGrcllGd, the initial cc,lll~osiLion nor-
mally will not be optically L-~ls~d.cnt, because of the sC~ttering of visible light, in a
thie~nto.cc of 1 c~ r~e~ ("cm"), and the oc~;ullcnce of the desired çh~.mi~ l interac-
tion can be ~lrlr----;-~d by the ~ rifi~tic)n of the culll~o~ilion~ If CO111~I1G1IL~ (A) and
(B) as defined above are both present in the precursor aqueous colllpo~iLion in suffi-
ciently high con~-e~ dLions, adequate ch~mi~l interaction b~,lwccn them may occur
3 0 at normal ~mhient ~r~ el~ s (i.e., 20 - 25 ~ C) within a pr~çti~l reaction time of
24 hours or less, particularly if CU1111)O11G11L (B) is dissolved or ~ e~1 in very finely
divided form. l!~erh~ni~ git~tion may be useful in spee~ling the desired çhemit ~l
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intPr~rtion and if so is preferably used. ~e~ting, even to relatively low lcln~cl~lulcs
such as 30~ C, is often useful in spee~lin~ the desired rh--mir.~ a~LiOn, and if so
is also ~.crcllGd. The desired ch~.mir~l intP.r~cction between components (A) and (B)
of the mixed composition ~ es or at least m~rko~lly reduces any tendency toward
settling of a rlicppr~ce~ phase that might otherwise occur upon long term storage of the
initial llfi~Llulc of col,lyollclll~ (A) and (B) as defined above.
The cw,,L)osilions rçs--lting from çhPmir~l interaction as described above may
then be utilized as metal treating cc,lll~o~il;onc, optionally after being comhinP-l with
a colll~oll~ (C) that is either (i) a water soluble or tlicpercihlP polymer and/or copol-
ymer, preferably sçlect~ from the group concictin~ of (i.l) polymers and copolymers
of one or more x-(N-R~-N-R2-~lll;,,~.,,-~lhyl)-4-llyL~,~y-~Ly,c.les, where x = 2, 4, S, or
6, Rl lcpl~cscllts an aLkyl group CO~ ;"i,~g from 1 to 4 carbon atoms, preferably a
methyl group, and R2 lc~l-,ScllL~ a :j~lbc~ group conrulll~illg to the general formula
H(CHOH)nCH2-, where n is an integer from 1 to 7, preferably from 3 to 5, (i.2) epoxy
resins, particularly polymers of the diglycidylether of bicphPn-)l-A, optionally capped
on the ends with non-poly.ll~ hhP. groups and/or having some of the epoxy groupshydrolyzed to hydlo~yl groups, and (i.3) polymers and copolymers of acrylic and
mPth~r.rylic acids and their salts; or (ii) a composition coll~;1;llil~g hexavalent chrom-
ium, and, optionally but preferably, trivalent chlullliull~.
Optionally, another culll~ollcl,L (D) made up of water soluble oxides, carbon-
ates, or hydroxides of at least one of Ti, Zr, Hf, B, Al, Si, Ge, and Sn may also be
added before, after, or cimlllt~nPously with c-,lll~ollcnt (C) but after the interaction of
coll~ollelll~ (A) and (B). For this y~u~ose~ "water soluble" means a solubility to at
least 1 % in water at normal ~ hiel)~ Ltlllpe.dlun;, and "water insoluble" means less
soluble than this.
The rçslllting co",~osiLions are suitable for treating metal surf~rçs to achieveçxrçllr.nt r~cict~nre to corrosion, particularly after subsequent convt;llLional coating
with an organic binder co~ in~ protective coating. The compositions are particu-larly useful on iron and steel, galvanized iron and steel, zinc and those of its alloys
3 0 that contain at least 50 atomic percent zinc, and, most preferably, ~ . " and its
alloys that contain at least 50 atomic percent ~l.~...;.,..,.~ The treating may consist ei-
ther of coating the metal with a liquid film of the co"l~o~iLion and then drying this
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liquid film in place on the surf~e of the metal~ or simply cont~ctin~ the metal with
the co.l-po~iLion for a sllmrirnt time to produce an h~ vcll~cllt in the .~ rc of
the surface to corrosion, and subsequently rinsing before drying. Such contact may
be achieved by spraying, i,.",~ inn, and the like as known per se in the art. When
5 this latter method is used, it is optional, and often advantageous, to contact the metal
surface with an aqueous cvlll~osilion cl mrricing polymers and copolymers of one or
more x-(N-RI-N-R2-~llinol..cll.yl)~-l.yd~y-styrenes, where x = 2, 4, 5, or 6, Rl rep-
resents an alkyl group Co"l~i"il~ from 1 to 4 carbon atoms, preferably a methyl
group, and R2 rt~.csents a .s~lhstitllent group COllrOlll~illg to the general formula
H(CHOH)nCH2-, where n is an integer from 1 to 7, preferably from 3 to 5, after con-
tacting the metal with a composition c~ g components (A) and (B) as ~ltoscrihed
above, rtllluvillg the metal from contact with this co..lpo~i~ion co"l~ i"~ co
(A) and (B) as described above, and rinsing with water, but before drying.
The invention also provides a process for cLrc.; ively coating the above-stated
mrt~llic surfaces in the absence of an i"~ tP. rinsing step. The process
c~ mrrices the steps of (i) cle~ning the metal surf~e to be coated, (ii) rinsing the
clo~nto~l metal surface with water so as to remove any excess clr~ning solution, (iii)
cont~rtinp the mrt~llir surf~e with the above-rlescrihed coating cc,lll~o~iLion, and (iv)
drying the coated mr~t~llic surf~e.
2 0 There is also another embodiment of the present invention which provides a
composition and process for coating ~.. r~r~c of ~l.. i.. and alloys thereof, whclci
the cunlposi~ion cnmprices, preferably consists essenti~lly of, or more preferably
consists of, water and a mixture of: (A') a water soluble or ~licprrcihle polymer having
at least one alcohol functionality 5rlectr-~l from the group co~cictinp of polyvinyl
25 ~lrohnl polyethylene glycol, mn-lifi~l starch, and ~ixl~.es thereof and (B') polymers
and copolymers of acrylic and mrth~crylic acid and their salts, and, optionally, one
or more of the following: a colllyol~ (c~) sel~octrA from the group col~ g of the
same fluorom~t~llic ~ids, with the same p.crclences, as recited for coll.pol,ent (A)
herein; a co ll~oncn~ (D') of mpt~llic and/or metalloid elements and their oxides,
3 0 hydroxides, and/or C~~ Lcs, with the same ~lcrclcnccs~ as recited for col..~o,.~ L (B)
herein; and a coll.~ncnt (E') selected from the group co~ li"~ of water soluble
oxides, carbonates, or hydroxides of at least one of Ti, Zr, Hf, B, Al, Si, Ge, and Sn
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as recited for co~ ullcnt (D) herein.
It should be Im-lrr.ctood that the ~1~serirtir,nc of compositions above do not pre-
clude the po.c.cihility of ~ c.-;rilocl chrrnir~ .deLions among the co.,l~ollcllL~ listed,
but instead describes the cclll~onG.lts of a composition according to the invention in
the form in which they are generally used as ingredients to prepare such a composi-
tion. In fact, a ch~ornir~l inLeld~;Lion, most probably to produce oxyfluro complexes
of the metal or metalloid cl- . l lr~ or their co.ll~ou.lds heated in contact with
fluorr,m~.t~llir acids, is believed to occur, but the invention is not limited by any such
theory.
Descli~lion of P~G~Il~,d Embo~1i",~.l"x
To the extent that their water solubility is sllfficient the fluoroacid cc~ ol~ent
(A) to be caused to interact in a mixture with one or more metals and/or mr.t~llc)i-l ele-
ments and/or oxides, hydroxides, and/or carbonates thereof in a process according to
one embodiment of the invention may be freely selectçd from the group consisting of
H2TiF6, H2ZrF6, H2HfF6, H3AIF6, H2SiF6, H2GeF6, H2SnF6, HBF4, and ll~i~lulGS thereof.
H2TiF6, H2ZrF6, H2HflF6, H2SiF6, HBF4, and ll~UL~ ,S thereof are plcr~lcd; H2TiF6,
H2ZrF6, H2SiF6 and l~Lulcs thereof are more ~lGr~ d; and H2TiF6 is most ~lcÇcllcd.
The cr,nr.r.ntr~tion of fluoroacid CU111~O1IGI1l at the time of illlcld;Lion is preferably be-
tween O.Ol and 7 moles per liter (hereinafter "M"), more preferably bGl~ 0.1 and6M.
The culll~ollcllt (B) of mrt~llir. and/or m.o.t~llr,i~l elPmr.ntc and/or their oxides,
hydroxides, and/or c~b~ a~cs is preferably sel~ctr.~l from the group cr~nci.cting of the
oxides, hydroxides, and/or c~lJolldLcs of silicon, ~ ;' l.;..,l., and/or ~l."..i.,...,. and more
preferably inr.llldt-s silica. Any form of this colll~ollent that is sllffiri~ontly finely di-
2 5 vided to be readily ~ ed in water may be used in a process accor~illg to one em-
bo~lim.o.nt of this invention, but for col.~ e-~ i of this colll~onclll that have low sol-
ubility in water it is pl~cr~.~lcd that the conctitllr.nt be amol~hou~ rather than crystalline,
because crystalline con.ctitllpnt.c can require a much longer pcriod of heating and/or a
higher Ir...l~ .c of heating to produce a c~ osiLion that is no longer ~usc~Lible
3 0 to settling and optically Lld~ d cnl. SrlllltirJnc and/or sols such as silicic acid sols
may be used, but it is highly preferable that they be ~ lly free from aLkali
metal ions as rle.srribecl further bclow. However, it is gen~ lly most prcr~,.lcd to use
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dispersions of silica made by pyrogenic ~locesses.
An equivalent of a m--t~llic or m.otAllni(l el~rn.o.nt or of its oxide, hydroxide, or
carbonate is defined for the purposes of this tlesr-rirtion as the amount of the m~t~.riAl
co~ i..g a total of Avogadro's Number (i.e., 6.02x1023) of atoms of metal andlor
5 metalloid ~lem~ntC from the group cnn~ tin~ of Ti, Zr, Hf, B, Al, Si, Ge, and Sn.
The ratio of moles of nuoluacid culll~ ellt (A) to total equivalents of Culll~ul~;llt (B)
in an aqueous composition heated according to one embo-lim~nt of this invention
preferably is from 1:1 to 50:1, more preferably from 1.5:1.0 to 20:1, or still more
preferably from 1.5:1 to 5.0:1Ø If desired, a con~titnent of this component may be
10 treated on its surface with a silane coupling agent or the like which makes the surface
oleophilic.
According to one embodiment of the invention, an aqueous liquid culll~?osiLion
comrri~ing, preferably con~i~ting e~PntiAlly of, or more preferably consisting of,
water and colll~ollellL~ (A) and (B) as ~1~5~-. ;l~d above, which colll~siLion scatters vis-
15 ible light, is not optically ~rA~ in a thi~n~ of 1 cm, and/or undergoes visually~l~tectAble settling of a solid phase if ...~;..l~;..~.-l for at least 100 hours at a le111Pe1A-
ture between its freezing point and 20~ C, is IllAilllA;n~3d at a lelll~ LulG of at least
21~ C, optionally with ~ Sr.hAnic~l Agit~tiQn~ for a sllfflri~ont time to produce a compo-
sition that (i) does not suffer any visually detect~hle settling when stored for a period
of 100, or more preferably 1000, hours and (ii) is optically IlAI~;PA~n~ in a thi~ n~
of 1 cm. Preferably, the tGlll~GlaLulG at which the initial m-ixture of colll~c~nents (A)
and (B) is mAint~in~d is in the range from 25 to 100 ~ C, or more preferably within
the range from 30 to 80 ~ C, and the time that the cornposition is II~A;~IIZ1;11I'd within
the stated t~ G range is wit_in the range from 3 to 480, more ~ f~;lably from
5 to 90, or still more preferably from 10 to 30, .. i.. ~ s (hereinafter often abbreviated
"min"). Shorter times and lower t~-..pf..,1l...c,s within these ranges are generally ade-
quate for c(~ Lillg c~slllposiLions in which the component (B) is selected only from
dissolved species and/or dispersed amorphous species without any surface Ll~t---- -~
to reduce their hydr~lJhilicity, while longer times and/or higher ~ dLulcS within
3 0 these ranges are likely to be needed if colllponellL (B) inrlndec ~li.c~r.~ed solid crystal-
line m~t~.ri~l.c andlor solids with ~... rAces treated to reduce their hy~l~upl-ilicity. With
suitable e~ ;p.. ~.. l for ~ the reaction mixture, even higher l~ A~ S than
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100~ C can be used in çspe~ lly difficult cases.
Indepcnfl~ntly, it is ~l~r~ cd that the pH of the aqueous liquid composition
combining Ccll~ ;>nellLs (A) and (B) as described above be kept in the range from 0
to 4, more preferably in the range from 0.0 to 2.0, or still more preferably in the range
from 0.0 to 1.0 before beginning ",~ n~ e at a l~ l.. c of at least 21~ C as de-
scribed above.
A co.llposiLion made as flescrihed imm~ t~ly above is suitable for use as a
p~ute-;livc L e;~ .l for metals. In many cases, however, a better protective tre~tml-nt
ccln~o~iLion may be obtained by mixing the product of interaction between colll~on-
10 ents (A) and (B) as des~rihc-l above with a third component (C) as also noted above.
To make such compositions in.~ln~ling CU111~U11G11L (C), after ~ n~ e of a COlll~Si-
tion co,~ g colllpollcllL~ (A) and (B) as described above at a tellll~cld~ c and for
a time s-lfflci~nt to promote their interaction, the cc,ll.~osiLion is pl~r~.dbly brought
if l~CPc~,y to a te~ cldlUlc below 30~ C and then mixed with a com~oll~,.lL consist-
15 ing of at least one of (i) at least one water soluble or ~ r.~ihle polymer and/or co-
polymer, preferably s~ cte(l from the group con~i~ting of (i.l) poly_ydroxyl alkyla-
mino dclivdLivcs of poly{p-hydro~y~Lylclle} as described above and, in more detail,
in U. S. Patent 4,963,596, the entire ~licclosllre of which, except to the extent cullLldly
to any explicit ~ herein, is hereby i. cûl~uldlt;d herein by lcrcl~,~lcc, (i.2) epoxy
2 0 resins, particularly polymers of the diglycidylether of hi~ph~nnl-A, optionally capped
on the ends with non-poly..l~ hle groups and/or having some of the epoxy groups
hydrolyzed to hy~u~yl groups, and (i.3) polymers and copolymers of acrylic and
m~th~rrylic acids and their salts; and (ii) a cu..l~osilion cu,.l;.;"i"g hexavalent chrom-
ium, and, optionally but plcrclably, trivalent Cl~ullliulll as known per se in the art for
treating metals, particularly ~hlminllm and its alloys, to retard corrosion thereon.
Suitable and ~lcfell~,d water soluble polymers and m~thn-l~ of ~lcpa hlg them are de-
scribed in detail in U. S. Patent 4,963,596. E'lcf~ldbly, the ratio by weight of the sol-
ids content of colll~ollent (C) to the total of active ingredients of co-ll~oncllL (A) as
~rriheA above is in the range from 0.1 to 3, more prcrcldbly from 0.2 to 2, or still
3 0 more ~lcf~,.dbly from 0.20 to 1.6.
A cc,l~l~osiLion p~cpdled by a process as described above cn~ s another
embodiment of this invention. It is nnrm~lly preferred that colllyo~iLions according
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to the invention as defined above should be ~ s~ lly free from many ingredients
used in cu~ osiLions for si-m- ilar purposes in the prior art. Speçifir~lly, it is often in-
creasingly ~lerc~lcd in the order given, indepçn~lf.ntly for each preferably ",;,~
co...pollellt listed below, that these cc~ poc;l;on~, when directly c-nt~rte~l with metal
in a process accol.ling to this invention, contain no more than 1.0, 0.35, O.lO, 0.08,
0.04, 0.02, 0.01, or 0.001 % of each of the following con.~l;lu~ hexavalent
dl~u~ u~ll; ferricyanide; ferrocyanide; anions cu..l~ molybdenum or tungsten; ni-
trates and other oxi-li7ing agents (the others being measured as their oxi~li7ing sto-
i-~hiomPtri~. equivalent as nitrate); phosrhnrus and sulfur C4--l;~ anions that are not
10 nxitli7.ing agents; alkali metal and ammonium c~tion~; and organic compounds with
two or more l-y~Lo~yl groups per mnlf cnle and a mol~c~ r weight of less than 300.
The prcfc,c,lce for minim~l amounts of alkali metal and ~mmnnillm cations applies
only to cu~ osiLions used for ~loces~es according to the invention that include drying
into place on the metal surface to be treated without rinsing after contact bc~ the
15 metal surface and the col.l~o~iLion cc,..l~ i..g at least cc...~ollents (A) and (B) as de-
scribed above; when a col.lpo~iLion accoldil g to the invention is cont~c~ with a
metal surface and the metal surface is subsequently rinsed with water before being
dried, any alkali metal and ~mmonillm ions present are usually removed by the rinsing
to a sllfficif nt degree to avoid any s~ l;on of the protective value of
20 subsequently applied organic binder c~ p~ute~;Livc co~ting~ Also, the prefer-
ence for ...il.;...;,;-l;on of the amount of hexavalent C~ullliulll present is due to the
polluting effect of hexavalent ~ u~liu---, and where there is an absence of legal
c~ against pollution and/or snffiri~ntly econ~lmic~l means of disposing of the
hexavalent d~lvll iu~- without e~lviiù~....f ..l;.l damage exist, this ~cÇt ~,nce does not
25 apply. In fact, in one speci~li7~l embodiment of the invention, as already noted
above, hexavalent Chlullliulll may advantageously be incol~uldlcd into working
cc,lllposiLions according to this invention themselves, and in another specizlli7f -1
embodiment of the invention, liquid cu-~l~osilions co..li.;..;.~g hexavalent dllollliu
may be used as posttre~tm~nt~ after application of a coating accordi-lg to this
3 0 invention but before final overcoating with a paint or the like, in order further to
ihl~luve corrosion re~ist~n~e of the metal surface treated.
The other major type of coating used in the invention, employing a coating
-
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cc,Lu~osilion inrlll-ling n~cçc~.y CO111~O11eL~7 (A') and (B') as already described above,
has been found to be espeei~11y useful for treating mrt~llic sllrfarçs that are exposed
to aLkali metal ions, particularly sodium such as often occurs in delGIgc.ll~, and other
rl~-an~r.c, after the llc~l",~ l with a culll~,osiLion according to this invention has been
5 complPtP~ ulc~livc coatings applied to mrt~llic sl-rf~res, particularly ah~...i..l.....
f~.dbly are water incolllhlr and inhibit corrosion. However, m~tallir s--rf~res bear-
ing a plulc-;live coating are often exposed to sodium ions later. It is believed that,
upon e~o~,u c of some prior art coatings to sodium ions, the sodium ions orl~"li...~s
at least partially replace the ~lllminllm in the formed coating, much as in an ion-ex-
10 change resin; such repl~rçmPnt in turn causes the film coating to be water sensitive,by increasing its sohlbility in water.)
In an effort to decrease adverse effects of allca'li metal ions on the treated sur-
faces, it has been found that by c- mhininp (i) polymers and copolymers of acrylic and
mPtharrylic acids and their salts having an average m~lçclllar weight of about 50,000
15 with (ii) a water soluble or dispersible polymer having at least one -OH group per
polymer m( l~rul~, adverse effects from e~o~,u c of the treated surface to aLkali metal
ions can be reduced. Possibly this occurs becduse the alcohol fimrtiorlality cross-links
by r"l~ . riri.lil~n with the acid fimrtionc In a particularly plGr~,.lGd embodiment of this
aspect of the invention, the composition cnnt~rt~d with a m~t~llic surface co...l., ;ces
2 0 water and: (A') from 0.5 to 50 gA and (B') from 0.5 to 50, and more ~lcrclably from
0.5 to 16 g/l of polyvinyl alcohol. The polyvinyl alcohol used in the invention
preferably is a low molecular weight polyvinyl alcohol which is 75 - 99+ mole %
hydrolyzed, and has an average degree of poly",~ ion rangin~ from 100 - 600.
While any water soluble or rlicpercihlP polymer having at least one -OH group
per polymer m-lrcllle may be employed without departing from the spirit of the in-
vention, ~lGrGllcd polymers and alllUUl1l~7 thereof include the above-stated polyvinyl
alcohol; from 0.3 to 16 g/l, preferably from 0.3 to 1.2 gll, of polyethylene glycol
having a m- lçcular weight of from 90,000 to 900,000; from 0.5 to 16 g/l, and prefer-
ably from 0.5 to 10 g/l of ~l.oxtrin, cyclo-lextrin, or a mnr1ifi~d starch.
3 0 The term "m~lifiPd starch" is one c-."".. ~l~ly known in the art. It refers to any
of several water-soluble polymers derived from a starch by ~etylation, chlorination,
~id hydrolysis, or el.~yL~ic ~tion. These lG~.-Iiol-c yield starch ~retates, esters, and
CA 02220419 1997-11-06
W 096/35745 PCT/U~.9_ha~25
ethers in the form of stable and fluid solutions and films. These starch deliv~lives
useful herein are well known.
The hydroxyaLkyl starch ethers and starch esters can be obL~ ed by known
eth~-rifir~fion and ~st~rifir~ti~.n pl~ cesses. These starch ethers and esters should have
5 a degree of ~ub~ irJn (hereinafter often abbreviated "D.S.") of 0.01 to 0.5, and
preferably 0.1 to 0.5. As used herein D.S. means the average degree of s~lhstitl~tion
of starch hydlu~yl groups per anhydroglucose unit of the r,h.omir~l modifying substitu-
ent, as for çY~mrl~ a hydroxalkyl or c~l,ullyl group.
Oxidized starch can be obtained by known ~lucesses involving oxidation of
10 starch with a suitable oxitli7ing agent, as for ~.x~ )lc sodium hypochltrite7 pot~ccillm
dichnJll~dle and sodium pPrrn~n~n~t~ The starch can be ~lXilli7P.~l under acid, alkaline
or neutral con~lition~, and the res--lting product can contain carboxyl and carbonyl
groups. Preferably the oxitli7~od starch has a "D.O." value of 0.01 to 1.0, where
"D.O." refers to the llulllbel of carboxyl groups introduced per anhydroglucose unit.
15 These starch dcliv~livc~. and mPthn-lc for cll.L~ l llg thern are ~licc~ccefl in Whistler and
Paschall (eds.), Starch: Chemistr~ and Technology, vol. I, (~ emiC Press, 1965), pp.
458 - 78.
Dextrins and cyclo-leYtrinc are polyc~ch~ri~lp- products of a complex nature re-sulting from the partial clegr~ tion of starch, such as corn starch, potato starch, wheat.
20 starch, and the like, with heat, as for ~Y~mrlP, by roasting with acid or Rlk~lin~. cata-
lysts. Linear and hr~n~h~ extrinC are cl~ccifi~d in three types. The particular type
obtained depends on the heating time, ~c~ el~Lulc, and catalyst employed in the treat-
ment of the starch. These types are ~ ccifit~ as white d~Ytrinc, yellow or canary dex-
trins, and British gums, and all such tl~Ytrinc are suitable herein. White and canary
25 dextrinc are ~lcre~l~,d in that British gums are brown in color. White deytrinc are
preferably pregel~tini7P~l (made water soluble during m~nnf~ct7~lre)~ if nrcesc~ry, to
render them more readily mixed wit'n other water soluble colll~olle~ .. Dextrins and
m~tht~-lc for obtaining them are well known. See, for ~Y~mpl~7 Whistler and Paschall
op. cit., vol. I, p. 421 ff and vol. II, p. 253 ff.
The starch hydrolysates useful in the c ~ ,o~ilionC of this invention are a rela-
tively new class of starch m~t~ri~lc. These starch hydrolysates are made by ~.ul~je~;ling
a source of starch, such as her~inhefnre m~ntion~-l, to el~ylllc or acid tre~tmt~nt or a
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comhin~tit~n of both. It is ilL~yvl~L that the starch hydrolysate have a relatively low
dextrose equivalent (hereinafter often abbreviated "D.E."). The starch hydrolysate
should have a D.E. of from 2 to 35, and plere.dl~ly have a D.E. of from ~ to 25. The
most p cr~-cd m~tt-ri~l~ have a D.E. within the range of 5 to 15. (The term D.E. is
used herein to refer to the redllcin~ sugars content of the dissolved solids in a starch
hydrolysate c,~ cssed as percent dextrose as measured by the Luff-Schoorl method[NBS Circular C40, p. 195; also appearing in Polarimetry, Saccharimetry, and theSugars published by Frederick J. Bates and Associates].)
Particularly p crc--cd mo-lifi~d starches include cyclodextrin.c, which are mac-rocyclic non-re~ in~ D-glucosyl polymers co,.l;l;,.i.~P six or more D-~luco~yl residues
bonded by a-(I,4) links. A more det~iled description of cyclc-lextrin.c can be found
in Whistler and Paschall, op. cit., Vol. 1, pp. 209-224.
The pH of a cor-~~osilion according to this invention that contains culll~ol~ell~
(A') and (B') as n~cccs~y culllL,oncllL~ preferably is in the range from l.0 to 5.0, and
more ~lcrc.~bly from 1.0 to 3.5.
In a plcfc lcd embodiment of the aspect of the invention lltili7ing nPcecs~ry
cvlll~)oncllL~ (A') and (B'), the treating colll~osiliull also in~ rlPc from 0.2 to 19.0, and
more preferably from 0.2 to 8.0 g~, of fluvluacids colll~vllent (C') ~rlmiYIo(l therein.
Cvlll~vnclll (C') is preferably SP~ ct~l from the group c~ of H2TiF6, H2ZrF6,
2 0 and H2SiF6, and more preferably is H2TiF6 or H2ZrF6.
Still another embodiment of the invention is a process of treating a metal with
a composition ~.~ed as described above. In one embodiment of the invention, it
is ~crcllcd that the aqueous coll.~osiLion as described above be applied to the metal
surface and dried in place thereon. For ~Y~mplP, coating the metal with a liquid film
may be accomplich~d by ;- ~---~ ;--g the surface in a cn-~ cr of the liquid compo-
sition, spraying the composition on the snrfare, coating the surface by passing it
between uppcr and lower roiiers with the lower roller ;.. ~.~e~l in a co"t~;"~r of the
liquid composition, and the like, or by a ~lulc of m~tho-l~, P-Y~eS.C;Ve amounts of
the liquid cu~ osilion that might uLIlcl wi~e remain on the surface prior to drying may
3 0 be removed before d~ying by any collvc ~icnL mPth~d, such as ~ n~ge under the influ-
ence of gravity, squeegees, passing bcLwccn rolls, and the like.
If the surface to be coated is a continll~us flat sheet or coil and precisely con-
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WO 96/35745 PCTIUS95/05225
trollable coating techniques such as gravure roll coaters are used, a relatively small
volume per unit area of a co,-r~ lel1 co"~o.ilion may effectively be used for direct
appli~tinn On the other hand, if the coating eq lipm~.nt used does not readily permit
precise coating at low coating add-on liquid volume levels, it is equally effective to
use a more dilute acidic aqueous co~"~o~.iLion to apply a thicker liquid coating that
ct-nt~inC t'ne same amount of active ingredients. In either case, it is plGfGll~d that the
total amount of active ingre~lientc of cu",~ùnents (A~, (B), and (C) and described
above dried into place on the surface to be treated fall illtO the range of from 1 to 500,
more ~lc;ÇGldbly from 5 to 300, still more preferably from 5 to 150, milligrams per
square meter (hereinafter often abbreviated as "mg/m2") of surface area treated.Drying may be accomplich~cl by any cûnvGllient ~ntothc)~l of which many are
known per se in the art; ~-x~mples are hot air and infrared radiative drying. Independ-
ently, it is ~lcfcllcd that the m~xi.~ elllpcldLulc of the metal reached during drying
fall within the range from 30 to 200, more preferably from 30 to 150, still more pref-
erably from 30 to 75, ~ C. Also in-l.orPn(l.-ntly, it is often p~Gf~ cd that the drying be
comrletetl within a time ranging from 0.5 to 300, mor~ rrçfer~hly from 2 to 50, still
more ~,cre~dbly from 2 to 10, secon-lc (h~rein~h~r abbreviated "sec") after coating is
comrleteA
Accul~lh~g to an ~ ;vc embo-lim~-nt of the invention, the metal to be treat-
2 0 ed ~lcf~.dbly is cont~rtP~l with a cc,m~osilion prepared as ~lesc~ ;l~d above at a temper-
ature within the range from 25 to 90, more plcfe.dbly from 30 to 85, still more pref-
erably from 30 to 60, ~ C for a time ranging from 1 to 1800, more preferably from
1 to 300, still more preferably from 3 to 30, sec, and the metal surface thus treated is
~llhseqllently rinsed with water in one or more stages before being dried. In this em-
2 5 bo-li--.,-.l, at least one rinse after LrP;~I " ,~i~l with a cu" ,l o.~il ion according this inven-
tion preferably is with d~;oni7~ iCtill.ocl7 or otherwise purified water. Also in this
embo-lim~nt, it is ~lc;f~ ,d that the m x;""",- Ir.~ e,~ c of the metal reached during
drying fall within the range from 30 to 200, more preferably from 30 to 150, or still
more p,cfc,dbly from 30 to 75, ~ C and that, indep~n(1~ntly~ drying be comrleted3 0 within a time ranging from to 0.5 to 300, more preferably from 2 to 50, still more
preferably from 2 to 10, sec after the last contact of the trcated metal with a liquid
before drying is cnmrlP.tf cl
12
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A process according to the invention as g~-n~-rally described in its ecct-ntial fea-
tures above may be, and usually preferably is, continued by coating the dried metal
surface produced by the tre~tm~onf as r~çs~rihed above with a siccdlive coating or other
protective co~tinp~, relatively thick as compared with the coating formed by the earlier
5 stages of a process accol lh~g to the invention as described above. Such protective
co~tingC may gen~.r~11y, in connRction with fhiS invention, be sç1RctP~ and applied as
known per se in the art. Surfaces thus coated have been found to have ext~ellent re-
cict~n~e to subsequent corrosion, as illllctr~tpd in the examples below. Particularly
~rcr~lcd types of protective coatings for use in conjunction witn this invention in-
10 clude acrylic and polyester based paints, en~mPlc, lacquers, and the like.
In a process according to the invention that includes other steps after the for-mation of a treated layer on the surface of a metal as described above and that oper-
ates in an enviiul-lllent in which the discharge of hexavalent cl.lullliulll is either le-
gally restrirte-l or ecnnc-mi~lly h~nr~ pped~ it is generally ~lcrellcd that none of
15 these other steps include c-~nt~rting the surfaces with any composition that co~ ,c
more than, with increasing preference in the order given, l.0, 0.35, O.lO, 0.08, 0.04,
0.02, O.Ol, 0.003, O.OOl, or 0.0002 % of hexavalent ch~ .l. Examples of suitable
and preferred cl-l~ull iulll free t~ are described in U. S. Patent 4,963,596.
However, in certain .cpeci~1i7t~ es7 hexavalent Chlullliulll may impart snfficiçnt
2 0 additional corrosion protection to the treated metal surfaces to justify the increased
cost of using and lawfully disposing of it.
Preferably, the metal surface to be treated according to the invention is first
cleaned of any c~ , particularly organic c~ ..tc and foreign metal fines
and/or inclusions. Such cl~nin~ may be acco...l,1ich~d by m~tho~lc known to those
2 5 skilled in the art and adapted to the particular type of metal ~ dle to be treated.
For e~ mp1R, for galvanized steel snrf~es, the ~.ubsLId~e is most preferably cleaned
wi ~ a cul.v~ .n;11 hot z~1k~iinP cieaner, then rinsed with hot water, squeegeed, and
dried. For ~1..., .;... ~.~ ., the surface to be treated most preferably is first c~ fl with
either an aqueous ~lk~lin~ c1e~ning solution in accordance with that ~lic~lose~1 in U.S.
3 0 Patent No. 4,762,638, ~colpola~Gd herein by rcrGlGllce, or an aqueous acidic r1.o~ning
solution as ~licçlosecl in U.S. Pat. No. 4,370,173, also i~cul~vldlGd herein by lGrGlGllce.
With respect to the aqueous acidic çlP-~ning solution, it should also be noted that a
=
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source of fluorirlP such as HF may also be employed to even further ~nhzlnre thecl~z~ning process. Irrespective of the type of ~lezlnin~ solution employed, the alumin-
um is then subjected to a water rinse, after which a composition in accordance with
the present invention may then be coated onto the Zllt~ .,., in acco~la~ce with the
5 processes disclosed herein.
The practice of this invention may be further appreciated by consideration of
the following, non-limitin~, working examples, and the benefits of the invention may
be further appreciated by reference to the c~ ;sol- examples.
GROUP I
COMPONENTS (A) AND (B)~ WlTH DRY IN PLACE TREATMENTS)
Test Methods and Other General Conditions
Test pieces of Type 3105 ztlll",;""", were spray cleaned for 15 secontlc at 54.4~
C with an aqueous cleaner cnl-t;lit-;..~ 28 g/L of PARCO~ Cleaner 305 (collllllel~;ially
available from the Parker+Amchem Division of Henkel Corp., Madison ~eight.c,
15 Michigan, USA). After clezlning, the panels were rinsed with hot water, squeegee~l,
and dried before roll coating with an acidic aqueous cc, ,~osiLion as described for the
individual exzlmrles and c-.",~lzl;co~ exzlmplPs below.
For this first group of eYzlmpl~s and coll.l ~l ;cOIl exzlmples7 the applied liquid
composition according to the invention was flash dried in an infrared oven that pro-
20 duces ~ llately 49~ C peak metal ~ ll.G. S~mples thus treated were subse-
quently coated, according to the lGco...llll ~ zltions of the suppliers, with various com-
mercial paints as cpecifiP-l further below.
T-Bend tests were according to ~m~riczln Society for Testing mz~t.-rizllc (herein-
after "ASTM") Method D4145-83; Impact tests were accordhlg to ASTM Method
D2794-84El; Salt Spray tests were according to ASTM Method B-117-90 Stzmdard;
Acetic Acid Salt Spray tests were ~colding to ASTM Method B-287-74 Standard; andmiclity tests were according to ASTM D2247-8 Standard. The Boiling water im-
mersion test was pGlr~,lllled as follows: A 2T bend and a reverse impact ~l~r~ nwere ~el~lllled on the treated and painted panel. The panel was then illllll~ for
10 .I.i.---lrs in boiling water at normal ~tmnsph~ric ~ 3~ule~ and areas of the panel
most ~ffectecl by the T-bend and reverse impact dcÇ~ li"nc were ~Ys....i..~cl to deter-
mine the percent of the paint film nri~in~lly on these areas that had not been exfoliat-
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ed. The rating is reported as a number that is one tenth of the ~Gl1ellL~ge of paint not
exfoliated. Thus, the best possible rating is 10, infli~tin~ no exfoliation; a rating of
5 inr1ir~tes 50 % exfoliation; etc.
Specific Compositions
5 ExamPle 1:
5.6 parts of amorphous fumed silicon dioxide
396.2 parts of deionized water
56.6 parts of aqueous 60 % fluotitanic acid (i.e., H2TiF6)
325.4 parts of deionized water
216.2 parts of an aqueous solution c~.. l~i.. i.. ~ a ~ Lur~ of 4.1 g/l polyacrylic acid
and 4.0 g/l polyvinyl alcohol
F~mrle 2:
58.8 parts of aqueous 60 % fluotitanic acid
646.0 parts of ~leioni7~l water
S.9 parts of amorphous fumed silicon dioxide
10.5 parts of zi~;ol~iu~l hydroxide
278.8 parts of the 10 % solution of water soluble polymer as used in FY~mrle 1.
Example 3
62.9 parts of aqueous 60 % fluotitanic acid
330.5 parts of rlei--~i7~d water
6.2 parts of amorphous fumed silicon dioxide
358.9 parts of deionized water
241.5 parts of the 10 % water soluble polymer solution as used in FY~mrle 1
Example 4
56.4 parts of aqueous 60 % fluotitanic acid
56.4 parts of deionized water
2.1 parts of Aerosil~ R-972 (a surface treated ~ per~ed silica)
667.0 parts of ~leinni7~--d water
218.1 parts of the 10 % water soluble polymer solution as used in F~r~mple 1
3 o Fx~mple S
58.8 parts of aqueous 60 % fllloti~nie acid
3.7 parts of amorphous fumed silicon dioxide
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10.3 parts of ~ ;olliulll basic carbonate
647.7 parts of deionized water
279.5 parts of the 10 % solution of water soluble polymer as used in Example 1
Example 6
5 52.0 parts of aqueous 60 % fluotitanic acid
297.2 parts of deionized water
3.3 parts of amorphous fumed silicon dioxide
9.1 parts of ~ ;olliulll basic carbonate
273.6 parts of deionized water
364.8 parts of the 10 % solution of water soluble polymer as used in F.~mple 1
Example 7
11.0 parts of fumed amorphous silicon dioxide
241.0 parts of deionized water
114.2 parts of 60 % aqueous fl-lotit~nic acid
15 633.8 parts of an aqueous cc,~ osilion prepared from the following ingredients:
5.41 % of CrO3
0.59 % of pearled corn starch
94 % of water
Example 8
666.0 parts of cl~-ioni7P~l water
83.9 parts of 60 % aqueous fluotitanic acid
5.3 parts of Cab-O-Sil~ M-5 fumed amorphous silicon dioxide
14.8 parts of zh~;olliulll basic carbonate
230.0 parts of RDX 68654TM (also known as RIX 95928T~S) epoxy resin dispersion
commercially available from Rhône-Poulenc, co.. ~ 40 % solids of poly-
mers of prer3O...i..n..lly diglycidyl ethers of bisphenol-A, in which some of the
epoxide groups have been co~ Led to hydroxy groups and the polymer
mol.-.clll~.s are phosphate capped
r,x~ lc g
30 656.0 parts of deionized water
183.9 parts of 60 % aqueous fluotitanic acid
16
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W 096/35745 PCTrUS95/05225
5.3 parts of Cab-O-SillM M-5 fumed amorphous silicon dioxide
14.8 parts of zil~eolliulll basic carbonate
240.0 parts of Accumer~ 1510, a cc,ll.~ ;ially available product from Rohm &
Haas co~ g 25 % solids of polymers of acrylic acid with a molecular
weight of 60,000
Example 10
636.2 parts of ~lF.ioni7:F.cl water
83.7 parts of 60 % aqueous flllotit~nic acid
5.3 parts of Cab-O-SilTM M-5 fumed amorphous silicon dioxide
14.6 parts of ~i,colliul" basic carbonate
37.6 parts of the 10 % solution of water soluble polymer as used in Example 1
222.6 parts of ~cumFrTM 1510, a commercially available product from Rohm &
Haas co~ 25 % solids of polymers of acrylic acid with a molec~ r
weight of 60,000
For each of FY~mrl~.s 1 - 6 and 8 - 10, the ingredients were added in the order
inAic~te.~l to a c~mt~inFr provided with stirring (Glass containers are susceptible to
ehFmie~l attack by the compositions and generally should not be used, even on a lab-
oratory scale; c.~..l;.il-F..x of ;~ r~ c st~inlr.ss steels such as Type 316 and c(J.~ F-.x
made of or fully lined with ,c~isL~,L plastics such as polymers of tetrafluoroethene or
20 chlo~LIinuoroethene have proved to be s~ticf~tory.) In each of these FY~mples ex-
cept F.Y~mrl~F 4, after the ~AAition of the silica co~lpollc~L and before the addition of
the subsequently listed cu",po,lenL~, the ,.li~Lu,e was heated to a IG111~C1dlU1G in the
range from 38 - 43 ~ C and m~int~inFcl within that range of telll~FldLu,cs for a time
of 20 - 30 ...i....l~.c. Then the ~ u~e was cooled to a Lclll~cla~ul~, below 30~ C, and
25 the ,~ ;;g ingredients were stirred in without ~Mition~l hr.~ting, until a clear solu-
tion was obtained after each ~AAiti~m
For FY;~ 1r 4, the SiO2 used was surface mnAifiF~l with a silane, and because
of its hy~ Jphobic nature, the 111i~LU1C COIII71;;l;llg this form of silica was heated for 1.5
hours at 70~ C to achieve ~ IG~1~;Y. The ,~~i;.-g steps of the process were the
3 0 same as for FY~mrle 1.
For FYzt.l.l)lr. 7, the first three ingredients listed were miYed together and main-
tained at 40 + 5 ~ C for 20 - 30 ~ ..;....~s with stirring and then cooled. In a sep~r~tF
17
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CA 02220419 1997-11-06
WO 96135745 PcTluS9-~J~522s
cont~inPr, the CrO3 was dissolved in about fifteen times its own weight of water, and
to this solution was added a slurry of the corn starch in twenty-four times its own
weight of water. The mixture was then ,-~ for 90 minllteC with gentle stirring
at 88+6 ~ C to reduce part of the hexavalent Chr~llliUlll content to trivalent cll,~lll.ulll.
5 Finally, this mixture was cooled with stirring and then added to the previously pre-
pared heated mixture of fluotitanic acid, silicon dioxide, and water. This composition
is used in the manner known in the art for compositions c-",l~ lg hexavalent and tri-
valent chl~,l,.iu", and tli~p~r~ed silica, but it is much more stable to storage without
phase separation.
Co~ ~dLiv~ Exdmple 1
18.9 parts of aqueous 60 % fluotitanic acid
363.6 parts of the 10 % solution of water soluble polymer as used in FY~mrle 1
617.5 parts of deionized water
Cc,lllpaldLive Example 2
18.9 parts of aqueous 60 % fluotitanic acid
71.8 parts of the 10 % solution of water soluble polymer as used in FY~mrle 1
909.3 parts of d~-ioni7~-~l water
For Coll~ Livt; FY~rnrles 1 and 2 the col..~ollents were added together with
~gitz~tic)n in the order inr1ir~t~-tl, with no heating before use in treating metal s~ rçc
Add-on mass levels, specific paints used, and test results with some of the
compositions described above are shown in Tables 1 - 5 below.
CA 02220419 l997-ll-06
W 096/3574~ PCTrUS9~ 3>25
TABLE l: Panels Painted with PPG DuracronTM lO00 White Sin~zle Coat Acrylic Paint
- T~ l Boilin~ Water Coating HAc Salt ~nmirlity
2T Bend Impact Wei~ht Spray 1008 Hrs.
504 Hours
-
P.y~mrl~ 1 9 10 65 mg/m e 0-lS Vf9
asTi sO-ls
9 lO 43 mg/m e 0-15 Vf9
asTi sO-ls
Col~ , 5 7 39 mg/m e 0-lS D9
F.Y~mplt~ 1 as Ti s 0 25
0 0 27 mg/m2 e 0-lS D9
as Ti s 0-2S
Co",~ ive 7 8 65 mg/m2 e 0-lS Vf9
20PY~mpl~o 2 as Ti s O ls
4 6 29 mg/m e 0-lS Fm9
as Ti s O_lS
TABLE 2: Panels Painted with LillyTM Black Sin~le Coat Polvester
Salt
HAc Salt Spray
Treat- Boilin~ Water Coating Spray 504 1008 Humidity
ment 2T Bend Impact Wei~ht Hours Hours 1008 Hrs.
Example 10 10 54 mg/m2 e O-1' e N
3 5 2 .as Ti s N s N Vf9
Example lOlO 64 mg/m2 e 0-2' e o-1a
3 as Ti s 0-2- s N V~9
19
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WQ 96/35745 PCT/US95/05225
TABLE 3: Panels Painted vith Lillv~M Colonial White Sin~le Coat Polvester
Salt
HAc Salt Spray
Treat- Boilinq Water Coating Spray 504 1008 Humidity
ment 2T Bena Im~act Weiqht Hours Hours 1008 Hrs.
0 Example 4 5 8 65 mg/~e N e N
as Tis N s N V~
Example 5 10 10 22 mg/~e N e N
as Tis N s N V~
Example 5 10 10 54 mg/~e N e N
s N s N V~
Example 6 lO 10 22 mg/~e 0-1' e N
s N s N V~
Example 6 10 10 54 mg/~e 0-1' e N
s N s N V~
Example 8 9.8 10 12 mg/~e N e N
s 0-1' s N N
Example 8 9.6 10 24 mg/~e N e N
s 0-1' s N N
Example 9 10 10 11 mg/~e N e N
s o--1~s o--r N
Example 9 9.8 10 24 mg/~e 0-1 e N
3 5 s 0-1's 0-1 N
Example 10 9.8 9.817 mg/~e 0-1' e N
s 0-1' s N V~
Example 10 9.9 10 25 mg/~e 0-1' e N
s 0-1~ s N V~
Example 10 9.9 10 33 mg/~e 0-1' e N
s 0-18 s N V~
CA 02220419 1997-11-06
W 096/35745 - PCTAUS95/05225
TABLE 4: Panels Painted with Valspar/DesotoTM White Sin~le Coat Polvester
Salt
HAc Sal t Spray
Treat-BoilinqWater Coating Spray 1008 1008 Humidity
ment 2T BendImpact Weiqht Hours Hours1008 Hrs.
10Example10 10 39 mg/m2 e 0-1' e N
2 as Ti s 0 _ 12 s N Vf 9
Example 10 10 48 mg/m2 e 0-1- e N
2 as Ti s 0 - 1- s N Vf 9
15Example10 10 70 mg/m2 e 0-25 e N
2 as Ti s 0 - 1- s N Vf 9
Example 10 10 87 mg/m2 e N e 0-1-
2 0 2 as Ti s 0 - 1- s N Vf 9
Example 10 10 29 mg/m2 e 0-2- e N
3 as Ti s 0 - 1- s N Vf 9
25Example10 10 42 mg/m2 e 0-1- e N
3 as Ti s 0 - 1- s N Vf 9
Example 10 10 57 mg/m2 e 0-1 e N
3 as Ti s 0--1- s N Vf 9
Example 10 10 82 mg/m2 e 0-2- e 0-15
3 as Ti s 0-2' s N Vf9
Example 7 10 65 mg/m2 e 0-1' e N
3 5 4 as Ti s 0 - 1- s N Vf 9
TABLE 5: Panels Painted with ValsparTM Colonial White Sin~le Coat Polyester
Sal t
HAc Sal t Spray
45Treat-BoilinqWater Coating Spray 504 1008 Humidity
ment 2T BendImpact Weiqht Hours Hours1008 Hrs.
Example 10 10 54 mg/m2 e N e N
2 as Ti s N s N E m9
Example 10 10 64 mg/m2 e 0-15 e 0-15
3 as Ti s N s 0 - 1- Fm9
-
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W096/35745 PCTrUS9~ 225
The storage stability of the compositions according to all of the P~mrles
above except FY~mrle 2 was so good that no phase sep~r~tion could be observed after
at least 1500 hours of storage. For F.Y~mrle 2, some settling of a slight amount of ap-
parent solid phase was observable after 150 hours.
GROUP II
COMPONENTS (A) AND (B). WITH SPRAY TREATMENT)
To obtain the results reported below, an ~ltprn~tive process of treating the
metal surfaces according to the invention and different ~ll.."il,."" alloys were used.
SpP~rifir~lly, in part I of this Group, test pieces of Type 5352 or 5182 ~ were
spray clP~ne-l for 10 seconds at 54.4~ C with an aqueous cleaner C~JIII;1;1~;1~g 24 g/L
of PARCO(~ Cleaner 305 (c~.llllllr~.l~-;~lly available from the Parker+~mrhpm Division
of Henkel Corp., M~ on ~eight~, Mirilig~n~ USA). After rle~ning~ the panels wererinsed with hot water; then they were sprayed with the, e~e~;live tre~tmrnt solutions
acco.dillg to the invention, which were the same as those already ~P.srrihed above with
the same Fx~mple Number, except that they were further diluted with water to thecollct;~ dLion shown in the tables below, for S seconds; and then were rinsed
s~lcces~ivt;ly with cold tap water and deioni7e-1 water and dried, prior to p~inting
The "OT Bend" column in the following tables reports the result of a test
procedure as follows:
1. Fe.Çc,l.-l a 0-T bend in accordance with ASTM Method D4145-83.
2. Firmly apply one piece of ~610 Scotch(~) tape to the area of the test panel with
the O-T bend and to the ~dj~rPnt flat area.
3. Slowly pull the tape off from the bend and the ~di~rent flat area.
4. Repeat steps 2 and 3, using a fresh piece of tape for each repetition, until no
additional paint is removed by the tape.
5. Report the m~imllm rlict~nre from the 0-T bend into the flat area from which
paint removal is observed according to the scale below:
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Paint loss in mm Rating
0 5.0
0.20 4.9
0.30 4.8
0.8 4.5
1.6 4.0
2.4 3.5
3.2 3.0
4.0 2.5
4.8 2.0
5.6 1.5
6.4 1.0
7.2 0.5
>7.2 0
lS The "Ninety Minute Steam Exposure" columns of the tables below report the
results of tests ~elrvlllled as follows:
1. Expose the painted .c~mples to steam at a temperature of 120~ C steam for 90
minutes in a ~lCS~ulc cooker or autoclave.
2. Cro,cch~tr-h the painted sample - two perpe~-lir~ r cuts; a Gardner crocch~trh
2 0 tool with 11 knife edges spaced 1.5 mm apart was used.
3. Firmly apply #610 ScotchTM tape to the c,osch ~Irh~l area and remove tape.
4. F~ minf the crosch~tr-h~l area for paint not removed by the tape and report
a number lcp,-,senl;--~ one-tenth of the pe,~;cl,~ge of paint rem~ining
5. Using a microscope at 10 - 80 times m~gnific~tion, visually observe
crosch~trh.o~i area for blictrrin~, and rate size and density of blisters.
The "15 Minute Boiling DOWFAX~M 2Al TmmPncion" columns of the tables
below report the results of tests pc,rulllled after l,~ l as follows:
1. Prepare solution of 1 ~o by volume of DOWFAXIM 2Al in deionized water
and bring to boil.
3 0 2. T.. ~. ~e painted test panels in the boiling solution ~lG~ucd in step 1 and keep
there for 15 ...i....l~s, then remove panels, rinse with water, and dry.
DOWFAX~ 2A1 is cv~ "c;~iially available from Dow Chtornir~l and is de-
scribed by the supplier as 45 % active sodium dodecyl L~Lcllyloxide lliclllf n~t~ The
"Cross Hatch" test after this l~c~ .l was made in the same way as ~esrrihecl above
CA 022204l9 l997-ll-06
W 096/3574~ PCT~US95/05225
for steps 2 - 4 after "Ninety Minute Steam E~o~ ;". The "Reverse Impact" test was
made as described in ASTM D2794-84El (for 20 inch pounds impact), then proceed-
ing in the same way as described above for steps 3 - 4 after "Ninety Minute Steam
Exposure". The "Fe~th~-rin~" test was ~lÇolllled as follows: Using a utility knife,
5 scribe a slightly curved "V" on the back side of the test panel. Using sc-icsnrc, cut up
about 12 millimt-terc from the bottom along the scribe. Bend the inside of the V away
from side for testing. Place sample in a vise and, using pliers, pull from the folded
section with a slow continuous motion. Ignore the part of the panel between the top
edges nearest to the vertex and a line parallel to the top edge but 19 mm away from
10 it. On the r~m~in-ler of the panel, lllea~ulc; to edge of fe~thPring in millim~terc Re-
cord the largest value observed.
The results of tests according to these procedures are shown in Tables 6 - 8
below.
TABLE 6: 5352 AlloY Panels Painted with Vals~arTM S-9009-139 Paint
Inven- Concen- ~H Coating OT Bend Ninety Minute
tion tration Weiaht Steam Ex~osure
Compo- Cross Blist-
sition Hatch erinq
Example 1~ 2.7 4.0 5 lO Very
1 mg/m2 ~ew,
2 5 as Ti small-
medium
Example 1% 3.2 11.4 5 lO ~ew,
1 mg/m2 small
as ~i
Example 3% 2.5 2.3 5 lO very
1 mg/m2 few,
as Ti very
' small
Clean N/A 1.5 lO ~ew,
only medium
(Com-
pari-
son)
24
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TABLE 7: 5352 Allov Panels Painted with ValsDarlM S-9009-154 Paint
5 Inven- Concen- E~ Co~ting OT Bend Ninety Minute
tion tration Weiqht Steam ExPosure
Compo- Cross Blist-
sition Hatch erinq
lOExample 1% 2.9 4.2 5 9-lO Very
1 mg/m2 few,
as Ti small
Example 3% 2.7 2.6 5 9-lO very
1 mg/m2 few,
as Ti very
TABLE 8: 5182 alloY Panels Painted with Vals~arTM S-9835002 Paint
20 Inven- Concen- E~ Coating 15 Minute Boiling DOWFA~
tion tration Weiqht 2A1 Immersion
sitlon Cross Reverse Feathering
Hatch Impact
25Example 1 % by 2.9 7.9 mg/~ lO lO 0.35 mm
1 weight as Ti
In part II of this Group, Type 5352 ~ .. n was used, and the process se-
30 quence used in part I, except for final drying, was used but was then followed by
passing the test pieces, still wet from the deionized water rinse after contact with a
composition ~cording to this invention, through power driven squeegee rolls arran~e-l
so that the test pieces passed through the squeegee rolls in a h~l~ont;ll position im-
m~ t~ly after being sprayed liberally with the final tre~tm.-nt liquid composition at
a telll~ ulc of 60~ C before being dried. In Examples 11 and 13 the LlC~l.. '~t
liquid in this final stage was simply d.-ioni7lod water with a con-lucLivily of not more
than 4.0 ~ ml3n~/cm, while in F.Y;....~ 12 the LIC~ ..I Iiquid in this final stage was
obtained by mixing 35 ml of Parcolene~ 95AT and 2.0 rnl of Parcolene~M 88B with
7 liters of deionized water and had a pH of 5.18 and a conducliviLy of 56 IlSie-
4 0 mens/cm. (Both Parcolene~ products noted are cul~ ,ially available from the Par-
ker+~mrhPm Div. of Henkel Corp., ~licon ~ei,e~ht~ hig~n ) This latter type of
final Llc;~ ll liquid is an çx~ . of one cf l.l;.i..;..g polymers and/or copolymers of
one or more x-(N-Rl-N-R2-~minomPthyl)-4-llydlu~y-styrenes as already described
above.
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Concentrate II-II used in each of Examples 11 - 13 had the following
composition:
1892.7 parts of deionized water
83.7 parts of 60 % aqueous fluotitanic acid
5.3 parts of Cab-O-SilTM M-5 fumed amorphous silicon dioxide
18.3 parts of zirconium basic carbonate.
These ingredients were simply mixed togeth~o-r with llrccl.~-iç~l agitation in the order
shown, with a pause after each addition until the solution became optically clear. Al-
though the partial mixture was not Lld~ a-tnt immP~ t~ly after ~d-lition of the silicon
10 dioxide, it became clear after a few minntec of mixing, even without any hP~ting
The working solution for FY~mples 11 and 12 was ~-c~d-~,d by rlilntinp~ 200
grams of the concentrate II-II, along with sufficient sodium c~l,olldLc to result in a pH
of 2.92 + 0.2, to form 6 liters of working composition. For F.x~mrlr 13, the working
solntion was made in the same way, except that it also co~ S grams of a
15 c~ e~ t~cl polymer solution made according to the directions of column 11 lines 39
- 49 of U.S. Patent 4,963,596, except as follows: The plcpalaLion was carried out on
a ~lbsl;1..li~lly lOEger scale; the pl~lLions of ingredients were rh~n~d to the follow-
ing: 241 parts of Propasol~ P, 109 pOEts of Resin M, 179 pOEts of N-methyl~lnr~m-
ine, 73.5 parts of aqueous 37 % fc-~m~kl~hyde, and 398 pOEtS of deioni7~ water, of
20 which 126 pOEts were reserved for a final ~dtlition not described in the noted patent,
with the rrm~in-l.or used to slurry the N-methylp~lnc~mint-- as noted in the patent; and
the telllpcldLulc noted as 60 - 65 ~ C in the patent was reduced to 57~ C.
The dried test pOEnels were then coated with ValspOE~ 9009-157 paint accord-
ing to the directions of the paint supplier, and the paint coated panels were tested as
25 described for the tests of the same name in part I of Group II. Results OEe shown in
Table 9.
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TABLE 9
FY~n1P~? mg of Ti/m2 O-T Bend 90 Minute Steam F~ --
Number Cross Hatch Bli~
1 1 3.6 4.5 10 4.5
12 4.6 4.9 10 4.5
13 5.4 4.8 10 4.0
GROUP m. W~H NECESSARY COMPONENTS (A') AND (B')
Example 14
A first concentrate was made by mixing 750 parts of tap water and 274 parts
of AcrysolTM A-l, a commercially available product from Ro_m and Haas c~nt~ining25 % solids of polymers of acrylic acid with a mol~c~ r weight of less than 50,000.
15 A second con~-e.~ te was made by mixin~, in a cont~in~r scpdldLe from that used for
the first co~--e~ dle 951.3 parts of tap water and 66.7 g/l of Goh.~nol~M GLO-5, a
ccmm~-cially available product from Nippon Gohsei which is a low m~ L-nl~r weight
polyvinyl alcohol; the latter was added to the tap water with stirring at a slow and
controlled flow, after which the ICl.l~?CldLulc was increased to 49 - 54 ~ C for 30 min-
2 0 utes with slow stirring until all was dissolved.
An amount of these cs~n~e~-l.dtcs equal, for each concentldle separately, to 6
volume % of the final volume of collll,osilion ready for treating a metal surface
acc.,ldillg to this invention, was then added with stirring at ambient Ir....p~.".l...G to a
large excess of water, and after ~d~lition of bot_ concelllldlGs, additional water was
25 added to reach the final volume of LlrA~ ...l composition, w_ich contained 4.1 g/l of
polyacrylic acid and 4.0 g/l of polyvinyl ~ ,h- l
This cc. o~ilion was then c-nt~r.t~ with an ~1.. ;... surface by dipping or
spraying for a time from 30 to 60 secon-lc, after w_ich time the surfaces treated were
removed from contact with the treating composition, allowed to dry in the ~mhient
3 0 ~ S~ G without rinsing, and then baked in a warm air oven at 88~ C for S ~ lrc
to ~imnl~t, c~ ;;al OpGldlillg con-liti~ n~. The s~lrf~--es thus ~lc~Gd were painted
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W096/35745 . PCTnUS95/05225
with col.vc~ n~l paints.
Examples 15 - 20
In each of these eY~mplP,s, the treating culllpo~i~ion is prepared in the same
general manner as in F~x~mpl~ 14, by making separate concentrates of the hydroxyl
S group co..~ .;..g polymer and polyacrylic acid co~ olle.l~, mixing an apl)r~liate
amount of these conccn~ldLcs with a larger volume of water, adding any additional
Colll~ol~clll~ used, and finally adjusting to the final desired volume or mass by the ad-
dition of more water. These compositions are then applied to ~ ",;""", surfaces in
the same manner as described for F.x~mple 14. The specific active ingredients and
10 con~çntr~fiorl~ or amounts thereof in the llc,.l",~,..t composition for each ex~mple are
as follows:
Example 15: 4.1 g/l of Acrysol~M A-l; 4.0 g/l of GohsenollM GLO-5; and 1.2 g/l of
hto,x~flllo,~ ;ol~ic acid.
Example 16: 4.1 g/l of AcrysolTM A-l and 0.6 g/l of polyethylene glycol having a molec~ r weight of less than about 600,000.
Example 17: 4.1 g/l of Acrysol~M A-l; 0.6 g/l of polyethylene glycol having a molec-
ular weight of less than about 600,000; and 1.2 g/l of hexafluolo;ci.conic acid.Example 18: 4.1 g/l of AcrysolTM A-l and 0.8 g/l of dextrin.
Example 19: 4.1 gll of AcrysolTM A-l; 0.8 g/l of dextrin; and 1.2 g/l of hexafluoro~i-
2 0 tanic acid.
ExamPle 20: 651.4 parts of deinni7~1 water; 83.7 parts of 60 % aqueous fluotitanic
acid; 5.3 parts of Cab-O-SilTM M-5 fumed amorphous silicon dioxide; 14.6 parts of
~U-;olliulll basic C~LIoll~c; 200.0 parts of ~c,--m~rTb~ 1510, a cullllllcl.:ially available
product from Rohm and Haas co..l;1il,;,.f~ 25 % solids of polymers of acrylic acid with
a mnl~c~ r weight of about 60,000; and 55.0 parts of ~Toh~PnolTM GLO-5.