Note: Descriptions are shown in the official language in which they were submitted.
73~
-- 1 --
SPECIFICATION
~TITLE OF THE INVENTIONJ
FISHING LINE
tTECHNICAL FTELD]
The present invention relates to flshing lines
for use in fishing and, more particularly, to impl~v~ ~t
in the structure of fishlng lines by which their kno~
strength, curling characteristic, and kink characteristic
can be ~ uved while the fl-nd~mental characteristic~ as
f~sh1ng l:Lnes are satisfied.
~BACKGROUND OF THE INVENTION]
A~ fishing lines for u~e ln flshing, there have
convent10n~11y been adopted synth~etlc resln wires c~ ose~
of polyamide, polyester, or polyvinylidene fluoride rasin,
or metal wires composed of piano steel wire, stainl~ss
~teel wire, or tungsten ste,el wire. Fun~r - tal
aharacteristics required for such ~1 sh~ ng lines include a
lower cutwater reslstance, a better bite sensitivity, les~
~ubaqueous deterioration in the sea and river, and even
flexibility~ Moreover, the fishing lines are required to
have different characteristlcs depend1 ng on the typ~ o~
fish to be ~aught as well as on the way of f19h~n~, and
according to these characterlstic requirements the
afo~ tioned materials ars ssleated. For example,
~ 2 -- 2~73~
fishlng for ayu with a live decoy goes in such a way that
the cat~ch is drawn out ln a rapidly flow1ng river
approxlmately the lnstant the strlke occurs, in which case
the ~ishlng lines lnvolved are required to have greater
tensile strength against impact force in addition to the
flm~ ~ntal characteristics descr~bed above. Therefore,
the flshing llnes for use in fishing are preferably metal
wlres that have about 1~5 times larger tensile strength
than synthetic resin wires as well as smaller wire
diame~ers.
Also, of the above-described fishing lines there
has been a desire that such a one be realized as can be
improved in te~le strength while being made further
thin~er in wire diameter, and that still has sufficient
flexibility. Examples of such type of fishing llne lnclude
one disclosed in Japanese Patent Laid-Open Publication No.
62-257331. This prior-art fis~hing line i9 ~ormed by
~o~nln~ a plurality of amorphous metal wires together into
a stranded wire and further coating it with a synthetic
re~in. This typa o~ flshing line, which employ~ an
amorphous metal, allows its tensile strength to be lmproved
while being made thinner in wire diameter than conventional
metal wires such as pia~o stael wires. Moreover, since the
fishing line is structurQd by stranding together a
plurality of solid w$res, sufficient flexibillty can be
/~
- 3 - 2~7368
en~ured.
However, the prlor-art amorphou~ metal wire
according to the above-clted patent laid-open publicatlon,
although beiny superlor in tansilQ strength to those
conventional metal wires, yet has suffered from lower knot
strength for ~oinln~ two flshlng lines together or tying
the fishing line to the hook such that the wire is easy to
break. To pravent this, there has been adopted a
counte~ ~s~re that some adhesive is used to bond the wire.
Furtharmore, there is another problem in the
above conventional fishing lines that they are lnferior in
thelr ourllng characteristic and kink characteristic which
mat~er when some impaat force acts thereon.
The curling mentioned above refers to the fact
that a fishing line, when pulled into a tensional state
with a large load and thereafter abruptly freed thersfrom,
will ~e sub~ect to shape change in curls in itq
longlt~ n~l direction. A large amount of such curls will
cause the flshin~ line to be extended in length and re~uce~
in tensile strength. Therefore, it is of significance to
e the amount of curls in terms of improving the
service life of the fishing line.
The kink mentioned abova, in turn, refers to the
state in which the curled portions are bant at an acute
angle, bringing about a posslbllity that the f~sh~n~ line
- 4 - ~ 3~
may brea~c. Accordingly, occurrence of kinks can be a
~ critical wound for the fi~hing line. In consequence, lt 18
~mportant to 1n~ e the occurrence o~ both curls and
klnks with a view to ~ ~:uvlng the service life of fi~h~ng
lines.
One method of ~ _~ovlng the curl~ng and kink
characteristics may be that the fishing line i5 formed into
such a wire dlameter as to withstand any impact force;
~ howaver, in such a case, subaqueous resistance wlll
lncrease as much as the f~.ch~n~ line gets thicker, so that
it can no longer meet the fllndr -~$al characteri~tic for
the ~1 sh~ng line.
Accordingly, the obJect of the present invention
18 to provide a f~sh~n~ line which can be improved in their
knot strength wh~le satisi-ying the ~lln~r -ntal
characteri~tlcs for the f 1 sh~ ng line, and yet which ~.8
superior in curllng characteristio and kink charaateri~tlc.
tDISCLOSURE OF THE INV~NTION]
~he inventors of the prese~t invention have made
every effort to achieve the foregoing ob~ective, ~n~n~
that the occurrence of curls or kinks is related to both
the ~trand pitch of tha steel wire and the thl~kness of ths
synthetic res~n with which the stranded wire i~ coatad.
The pr~or-art f~sh~ng llne disclosed in the afor~ ~tioned
patent laid-open publlcation only involves forming thin-
- 5 - 2~$73~
resln film coatlng simply to prevent the stranded wires
from being loosened~ or specifying the strand pitch only to
~ rove the rol~n~nes~ and appearance. Accordingly, ~he
prior-art ~lshlng llnes cannot afford i ~lOY. ~ t ln the
curling characteristic and the klnk characteri~tlG, The
~nventors of the pre~ent invention have ~c~ llshed the
present invention by f~ ng out that specifying both ths
thir,kness of the synthetic resin film and the pitch of the
stranded wires allows the fishln~ line to be 1 oved ln
lts curling characteristic and kink charact~-ristic.
Further upon the metal wire itself to be employed
for fishing lines, the inventors of the present invention
have lnvestigated a metallurgical structure that allow~ its
strength to be substantially ~ ved even ~f its wire
diameter is th~nn~, reRch~n~ fln~ngs that follow~ That
i8, among others, superior in proces~~hillty is a steel
wire material having a c- .slte metallurgical structurQ ln
which a low-temperature transformation generative phase
which is an Fe-C-Si-Mn sarles ferrobased alloy and whioh i8
20 ~ 9~ of elongated martensite, baini~e, or a mlxed
structure thereof is dispersed uniformly into the ferrlte
phase. Use of a wlre material having such a metallurgical
~tructure ensures a simple, positive formation of an
ex~ ly thin wire having a wire diameter of 100 ~m or
lswer by using tha cold wire drawing technique. Moreover,
- 6 - 2Q~73~
processing such a steel wire material lnto a procQssln~
strain of 4 or more by using ~the cold drawlng technlque
will allow the formation of a uniforM fibrous fine
metallurgical structure in which the 1~- poslts materlal
formed in ~omblnation of the ferrite phase and the low-
temp rature transformatlon generatlve phase extends in one
direction. The resultin~ enLl~ ~ly thin wire having such
a metallurgical structure, lt was found, ls greatly
~ ~ved in tensile strength up to 300 to 600 kyf/mm2,
while its to~l~hness is equal to or around those of the
conventional piano wires or stainless wires.
From a viewpoint that the above-mentioned
metallur~ical structure primarily ~cco1~nt~ for the
_~v. -nt in tPnRile strength, the inventors of the
~5 present invention have made further studies on it8
relnfo.cF - t mechanism. As a :result, it was found that
metallurgical strua-tures having auch a ul~ra-high strength
as mentioned above have ~lber lntervals of 50 to 1000 A and
that the above-mentioned fibrous ~ ss~te structure ls
constltuted of 5 to 100 A ultra-fine cells.
Thus, a first aspect of the present ~nvention as
will be set forth in claim 1 is a fishing line in which a
~tranded wire provided by str~n~ a plurality of steel
wires is coated with a synthetic resin, characterixed in
that outer surfaces of the steel wires are coa~ed wlth an
- 7 - ~ 8
anticorroslon metal by plat~ng, the strand pitch ls 13 to
20 times the dlameter of the stranded wire, the th~ckness
o~ the synthatlc re~in i~ 4 ~m or more, and that the knot
Rtrength of the flshing llne is 50% or more of the stranded
w~re ~tren~th.
A secon~ aspact of the pres~nt invPntion as wlll
be set forth in claim 2 is a fishlng line accord~ng to
claim 1, wherein the steel wires are two-phase structured
low-carbon steel wires having a fibrous flne metallurgical
structure and having a tensile strength of 300 to 600
kgf /mm2 -
Now tha reason~ that claim~ onents ars limiteda8 herein described are eXpl~neA below.
First, the reason why the steel wires are coated
with an anticorro~ion metal by plating i8 to ~ ve the
~on~ng force with the outer resin and to p~event any
subaqueous deterloration. Avallable a~ the plating metal
are anticorrosion metals -~uch as Ni, Cu, Zn, and Al, whlle
means f or coating these metals may be wet plating or dry
plating or others, such as electroplating, and hot dipping.
' Second, the reason why the outer surface of the
6tranded wire is coatPd with a synthet~c resin i~ to
~ ~o~e the ro~n~ness as a whole and thereby reduce the
cutwater resistance, to protect the steel wires from water~
sea water, and the like, and to improve the knot strength.
- 8 - 2~73~
Available as thls resin are thermoplastic resins and the
llke such as polyamide, polyester, and polyurethane, whlle
means for coating these resins may be, for example, dip
coatlng whlch involves immersion into a resin bath.
What is meant herein by the thickness of the
resin is, as shown in Fig. 1, thicknes~ t equ~valent to a
half of the value resultlng from subtracting the outer
dlameter D of the circumscribed circle of a stranded wire
3 from the outer dlameter of a flshlng line 1, where a
resln thlrkness t of less than 4 ~m would result in
insufficiency ln the above-described effects. Although tha
upper limlt, ln turn, is not partlcularly deflned, too
thick a one would cause raductlon in tensile strength as
w~ll as deterioratlon in cutwater resistance and other
char~cterlstics. In thls respect, the thlc~ness of the
resln is preferably not less than 4 ~m and in the range of
0.1 to 0.5 times the strand~up cliameter.
~'~hird, the reason why the strand pitch i8 defined
~to 13 to 20 times the strand-up dia~eter in ths present
.~2~ invention is that this range of strand pltch has proved to
substantlally decrease the possibility of occurrence o~
curl~. Another reason is that any strand pitoh of less
than 13 tlmes the strand-up dlameter would cause residual
strain of steel wire~ to becoma too large while a 20 times
or more strand pitch would result in restoration of the
':
.~
9 ~ 7~
stranded wire due to elasticlty, maklng it impo~sible ln
~ some cases to ratain the configuration as a stranded wire.
In addltion, the number of steel wire~ constituting the
stranded wir~ i8 not particularly defined, but the seven-
wire str~nd~ng is stable in structure and satisfactory inro~lnflness, and even good in appearance.
Finally, the reason why the two-phase structured
lnw-carbon steel wires having a fibrous fine metallurgical
structure are adopted as steel wires ln the ~econ~ aspect
of the invention as in claim 2 is to ensure sufficient
ten~le strength required for a fishing line with the wlre
: diamstar even th~nned. This steel wire can be manufactured
in the following manner.
A wire material which ls c~ pose~ of 0.01 to 0.5%
by weight of C, 3.0% or lower by welght of Si, 5.0% or
lower by weight of Mn, and thle rest of Fe and other
lnevltable impurities and whiah iLs 3.5 mm or less in wire
diameter ls fir~t heated to a tempera ure range from 700 to
: 1100~C and then cooled (these heating and cooling may
repeatedly be effected over a plurality of times), 80 as to
prepare a wire material having a composlte metallurgical
structura in which a low-temperature transfor~ation
~; generativs phase c_ "oqed of martensite, bainite, or a
mlxed structure thereof, which may partly contain residual
au~tenits, i8 dispersed evenly into the fsrrite phase at a
':
-10- 2~ 3~8
volume ratio of 15 to 75~. In addition, there i8 a
descrlption of-quch a preparation mathod ln J~r~nP-se Patent
Laid-Open Publication No. SHO 62-20824.
Next, the composite structure wire material
obtalned ln this way is processad to a processing strain of
4 or more, preferably to 5 or more by the col~ wire drawing
technique, to c: ~ ne together the ~errlte phase and the
low-temperature transformation generative phase, thereby
forming a fibrous fine structure that e~tends in on~
direction as a metallurgical structure. Imp~oving the
degree of processing ln this way allows the fibrous
~tructure to be further microstructured and the flber
lntervals to be narrowed, thus lea~l ng to ths above-
described fibrou~ flne metallurgical structure having a
;; 15 size of c~lls oP 5 to 100 A yielded through processing and
~iber interval~ of 50 to 1000 A. In thls case, a thin wire
obtained through a drawing process with a processlng strain
of less than 4 would be on the way of development of the
fibrous structure, lmperfect in its structure, and
therefore low also ln its strength.
Described next is the re~o~s that various
conditions have been set for the above-described
manufacturing method.
C: To obtain the fibrous ~1ne metallurgical
structure according to the present invention and the
11 - 2~736~
tenslle strength mentloned above, lt is necessary to
restrict the amount of C to be added. As a result of
experiments, lt proved that a range of 0.01 to 0.05% i8
appropriate.
Si: Although Sl is effective as a rein~orcement
element for the ferrite phase, an excessive addition of it
beyond 3.0~ would cause the transformation temperature to
be markedly shlfted toward higher degrees and al30 cause
the sur$ace of the wlra materlal to be more likely
su~ea~ed to decarburization. Thus, the amount of ~ n~
S1 is set to an upper limit of 3.0%.
Mn: It i~ true that Mn has effects o~ reinforcing
the en~,~- -ly thin wire and enhanaing the hardenabllity of
the two phases, but an excessive addltion of lt beyond 5.0%
would only result ln saturation of these effects. Thus,
the upper limit of the addition is set to 5.0%.
Further, below explained are elements that are
preferably restricted in the~r contents, elements that may
b~ added, lnevitable impurlties, and the like.
H is a detrimental element that embrittles the
steel; tha higher the strength, the greater tha effect of
it. Accordingly lt is preferable in the present invention
to restrict it to 1 PPM or lower, and particularly
preferable to 0.5 PPM. Effective methods of decreasing the
amount o~ H in this case include de~assin~ treat~ent with
!
2~73~8
- 12 -
smelted steel, hot rolling followed by cooling aontrol
after heat-treatment wlth the wire material, and low-
temperature dehydrogenation control.
In the present invention, it i8 allowable to add
at least one element selected among Nb, V, and Ti so that
the metallurgical structure of the e~ ly thin wire i8
microstructured. These elements should be added at a ratio
of 0.005~ or more in each case; however, an excessive
addition of it would result only in saturation of its
effeot and besides disadvantageous from an ~oon- ic point
of view. Thus the upper limit of the addition is set to
0.5%.
Theabove-mentionedinevitable impurities include
S, P, N, and Al.
1~ S i9 preferably 0.005% or more to reduce the
amount of MnS, which allows the ductllity to be further
; ~ improved. Me~nwh~le, it is also desirabls to control tha
~; ~ confi~uratlon of MnS inclusion by ~fl~ n~ rare earth
ql~ --ts ~uch as Ca or Ce.
2n P i8 an element remar~able in intergranular
segrsgation: thu~ it~ content ~s preferably 0.01~ or lower.
N 1s an element that is most likely to age lf it
exlt~ in lts solid solution state; therefore, it may age
durlng proces~ing to hinder the development of the
prooes~hllity, or age after prooess~ng to deteriorate the
r-~
2~73~
- 13 -
ductllity o~ the extremely thln wire obtained through th~
drawlng process. Thus, lt i8 prsferably 0.003% or lower.
Al tends to Porm oxide-related inclusions, which
are difflcult to transform such as to hinder the
processabllity of the wire material; thus, normally it ls
preferably 0.01~ or lower. Besides, accordin~ as the Si/Al
ratio in the extremely thin wire bPS- ~S larger, silicate
inclusions increase; especially when the amount of Al is
small, the silicate-related lnclusions will rapidly
inaraase, c~llslng some deterioration in the dra~abllity as
well as that in the characteristic~ of the e~Lr~ ~ly thin
wlre obtained through drawing process. Consequently the
Si/Al ratlo hould be below 1000, and preferably below 250
for the present lnvention.
On the ~~ osite structure of the above-described
wire materlal, the oondition as set above that the volume
ratio of the low-temperature tran~formation generative
phase occupied in the ~errite phase ba in the range of 15
to 75% is attributed to the following rPason. With a ratio
of le3s than 15%, although it ls possible to obtain an
e~ ly thin wire having a wire dlameter of 100 ~m or
less by the cold drawing of the wire material hav~ng such
a composite structure, the e~Lc ~ly thin wire obtained
would result in some other than the flbrous fine
metallur~ical structure as described above, the fibrous
2~3S~
- 14 -
structure being lmperfect, and even in a tensile strength
of 300 kgf/mm2 or lower. Wlth a volume ratio of the low-
tsmperature transformatlon generative phase occupied in the
ferrlte phase being gxeater than 75%, on the other hand,
the wire material would be easy to break during the drawing
process; otherwlse, even if it could be drawn without being
broken, the en~.~~ ply thin wire obtained would result in
some other than the fine fibrous structure, as in the case
of the ratio of less than 15%, the fibrous struature being
imperfec~, and even in a tenslle strength as low as 300
kgf /mm2 or lower.
As for the volume ratio in the wire material, the
wire diameter and volume ratlo of the wire material are
restricted ~epen~ n~ on the form of the low-t e~ature
transformatlon generative phase, that i5, on whether the
~enerative phase is primarily elongated (or ~c~c~lar) or
globular ln shape. It is to bs noted here that l'elon~ated"
used above mean~ that particles have a directional property
while "g~o~ ar'i m~ans not.
Xn consequence, when 80~ or more of the low-
tem~erature transformation generative phase is elongated,
lt is ne~ess~ry that the volume ratio of the low-
temperature transformation genera*ive phase should be balow
50% and the wire diameter be below 3.5 mm, while when 80~
o~ the phase is globular, the volume ratio should be below
, - 15 - 2~73~
50% and the wire dlameter below 2.0 mm. Furthermore, when
the low-temperature transformation generative phase is a
mixed structure between elongated and globular structures,
tha volume ratio should be below 75% and the wire diamster
below 3.5 mm. In addition, although the lower limit of the
wire diameter that the wlre materlal should have is not
particularly de~ined, it is normally 0.3 mm by today's
technical standard.
~BRIEF DESCRIPTION OF THE DRAWINGS]
Fig. 1 is a sectional viaw for explainlng the
fishing line according to an e ~o~ t of the present
invention as claimed in claims 1 and 2;
Fig. 2 is a sche -tia view showing a stranded
state thereof; and
Flg. 3 is a characteristic view showing the
re~ults of experiments made in order to the effects of the
~ '~ nt of claim 2.
.
[BEST MODE FOR CARRYING OUT THE INVENTION]
Now an .- ~o~ ?nt of the present invention will
be ~ully described in con~unction with an ~ ~o~l ?nt
thereof.
Flg. 1 and Flg. 2 are views for sxplalning tha
fishing line according to an embodiment of the invention as
~ - 16 - 2~ ~73 ~
claimed ln claim l.
Referrlng to the flgures, des~gnat2d by referenc~
numeral 1 is the fishing llne of the present ~ ~lodl ?nt,
whioh i8 formed by tylng up seven steel wires 3a through
39, whose surfaces are coated with Nl plating 2, and
stran~1ng the circumferential steel wires 3b through 3g in
a splral manner lnto a stranded wire 3 with the steel wire
3a held in a linear state, and moreover coating the
stranded wire 3 with a synthetic resin 4. In this
con~ction, piano wires or stainless wires are used as the
steel wires 3a through 3g.
The strand pitch P of the stranded wlre 3 is 13
to 20 times the diameter D of the circumscribed circle o~
~the stranded wire 3, and the thic~ness t of the synthetic
resi~ 4 is 4 ~m or more.
According to the fishing line 1 of the present
~ 'o~ ?nt, as shown above, since the stranded wire 3 is
coated with the synthetic resin 4 with a thickness of 4 ~m
or more and the strand pitch P i5 set to be 13 to 20 timas
the diameter D of the stranded wire, the curling and kink
~ characteristlcs can be improved to a substantial exten~,
the service life of the stranded w~re being pr~longed,
Also, slnce the steel wires 3a through 3g are
coated with the Ni plating 2 and the resin thl~kness t i8
made to be 4 ~m or more, the bonding characteristic between
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- 17 -
the steel wire~ and the re~in aan ~e improved and the knot
strength al~o lncreased as much as more than 50~ of the
~ stranded wire stren~th~ Thus, it is pos ible to solve the
~ problem that the wlres are easy to break in tying up them
S as in the conventional case where a resin coating of 1 ~m
or so is formed onto the stranded wire composed of
amorphous metal wires.
Moreover, since the Ni plating is provided to the
aurfaces of the steel wires 3a through 3g, lt is possible
to prevent any subaqueous deterioration of the,wire and
hep~S ~ ~ve the bondlng characteristic with the
synthetic re in 4, which contributes to preventing the
resin at knot portions from being peeled off. Accordingly,
the resultlng fi~hing line can prevent any sound from being
generated in water and the knot portions from loose~l n~.
Here described are the experiments for
establishlng the effects of the fishing line 1 of the
pxesent embo~ t.
First referring to the fishing line adopt~d for
this experiment, plano wires and stainless wires (SUS304
; were employed as steel wires, where seven wires wer~
stranded together for each set of stranded wires in such a
~ way that the strand pitch would be 12 to 23 times the
dlameter D o~ the stranded wire. Then the resulting
3tranded wlres were coated with a synthetic resln having
7368
- 18 -
thic~ne~ses of 2 to 10 ~m, thus preparlng samples of
fishing lineR havlng diameters of 82 to 95 ~m. In
addltion, there was also adopted a stsel wlre which was not
coated with Ni plating, for comparlson. With these
sample~, the steel wire strength and ~not strength of the
f~h~n~ line~ were measured by tension test, and
sub~equently checke~ for their curling and kink
characteristlcs. These characteristics were evaluated by
the numbers of curls and kinks that have occurred per 250
mm of line when a 0.6 kgf impact load was applied to each
fishing line. To do this, the impact load was exerted by
abruptly cutting the fishing line with a 0.6 kg~ dead
welght su~pendA~. Also, how the resin at knot portions o~
each ~ishing line was peeled off was e~? ~ne~ as well.
The results are shown in Table l, where Nos~ 1
through 6 are assigned to plano wires whlle No. 7 is to
stainless wire9. As apparent from this table, there are
almost no differences in the steel wire ~trength nor in the
knot strength, a derived from the static load tests, among
20 ' samples of Nos. 1 through 7. However, the ~mpact load
test~ -show~d oacurrence of curls and kinks, mora
~pecifically 3 to 8 curls and 1 to 5 kinks, when the resin
thir~e~s was 2 ~m or less (No. 1), ths strand pltch was 12
times (No.3) and 23 time (No. 4), such that the ~ishin~
line may break. Furthermore, when no Ni pl~ting was
2~73~8
-- 19 -
applled ~No. 5~, there occurred 3 k1nks and 5 ourls aq it
was deterloration in characteristics. This i8 consldered
to be due to insufflciency in bondlng characteristlc of the
resin, in view of the fact that no surfaca fini.qh had been
made, although both the resin thir~nP.ss and the strand
pitch were wlthin the specified range. What 18 more, in
thls case, the resin at knot portions were peeled of~,
whlch may cause the loosen1ng of knots, occurrence of ~ound
in water, subaqueous deterioration, and the llke.
lOIn contrast to this, the samples according to the
present embodiment (No. 2, No. 6, and No. 7) resulted ln
only 2 to 4 curls and moreover no kinks that occurred while
they satisfied the requirements of both steel wire strength
and knot strength. Since ~ishing lines are subJect to
~c~sss1ve impact loads in actual use, less occurrence of
curls due to the impact load is~ essentlal to prolong the
service life of fishing lines. This being the case, the
~ h~ n~ llnes according to th~e present embodlment are
subJect to less occurrence of curls, as shown above, and
therefore ~r~h1e of improving their service life to a
grsat laap.
- Next described is a ~lshlng line according to an
c'1-ant of the pr~sent invention as w~ll ba sst forth ln
claim 2.
25The ~i hing l~ne of the present ~~~o~ -nt iR
- ;
- 20 - ~673
Just the same ln its structure as that ln Flg. 1 and F~g.
2, dif~erlng therefrom ln that two-phase structured low-
carbon steel wlres are employed as lts steel wlre~ 3a
through 3g.
The steel wlres 3a through 3g are pro~l~c~ by
process~n~ a 3.0 to 6.0 mm-in-diameter wire material, which
is composed of 0.01 to 0.50~ by weight of C, 3.0% or less
by weight of Si, 5.0% or less by weight of Mn, and the rest
of Fe and inevltable impurities, into a wire diameter range
of 15 to 100 ~m through primary heat-traatment, primary
cold drawlng, seCo~ry heat-treatment, and seco~d~ry cold
drawlng. These steel wires 3a through 3g are two-phase
structured low-carbon steel wires ln which pro~e~s~ cells
resulting from the proce-~s1n~ are arranged in ons diraction
ln a fibrous manner to form a fibrous fine metallurgical
structure, whare the proce.sse~ cells are 5 to 100 A, the
flber intervals are 50 to 100 A, and the tensile strength
is 300 to 600 kgf/mm2.
. According to the f~sh~ng line 1 of the preRent
: 20 embo~ -rlL, as shown above, the tensile strength of the
steel wires 3a through 3g are ~ubstantially improved in
their tensile strength as much as 300 to 600 kgf/mm~ as
compared conventlonal metal wires and amorphous wires.
Here described below are results of tha
~periments made to estahllsh the affects of the fishlng
.
- 21 ~ 73~8
line 1 of the present embodiment.
Experiment 1
; To do thl~ exper~ment, as shown in Table ~, seven
two-phase struotured low-rarbon steel wires having wire
diameters of 19 to 23 ~m were tled up together and stranded
80 as to prepare 5 stranded wires so that the strand pitch
P would be 12 to 16 times the wire diameter, and the
resulting stranded wires were coated with a synthetic resln
having thic~nesse~ of 3 to 10 ym, thereby fabrlcating
fishin~ lines having an outer diameter of 75 ~m ~Class 0.2)
(for experiment samples Nos. 1 to 5). Then the stranded
wlr~ strength and knot stren~th were measured wlth these
fishing lines. Also, the number of curls and kinks that
have occurred per 250 mm of line by applying impaot loads
of 0.5 to 1.0 kgf. ~o do this, the impact loads were
exerted by abruptly cutting the fishing llne with a dead
welght of 0.5 to 1.0 kgf suspendled.
Moreover, the same measurement was made ~or
s~ ~ison~ employing piano steel wires having a wlre
dlameter of 82 ~m (Class 0.25) with a r~sln thlckness of 8
~m and a strand pitch of 23 times and a nylon wire having
: a wlre diameter of 104 ~m (Class 0.4~ as well. In this
case, it would be re~on~hle to employ a nylon wire havlng
approximately the same wire diameter (78 ~m) as in the
~amples of the above-described embodiment; however, such a
~,
2Q~3~8
- 22 -
nylon wlre, when used, was broken only by applylng the
T ~ n1 impact load (0.5 kg~), which is the reason ~or
adopting the above one havlng the larger diameter ~104 ym).
As apparent from Table 2, it can be understood
that samples No. 1 through No. 5 of *he present embo~1 en~
~houed hlg~er values of both stranded wire strength and
knot strength than those of a little larger-in-d~ameter
plano steel wires ~82 ym~ and that they were, although a
little lower in knot strength, higher in stranded wire
strength for their smaller diameter as compar~d with the
nylon wire far larger in diameter (104 ~m).
Referrlng to the number of curls and kinks that
have occurred, the sample~ of No. 1 and No. 2 of the
present ~ ~odlment are approximately equal to that of piano
~teel wires snd those of the nylon wire in terms of normal
impact loads of 0.5 to 0~7 kgf; however, samples having
preferable structure~ (experiment samples No. ~ and No. S)
~: showed substantially reduced numbers of curls and kinks
that have ocaurred, which means great 1- o~ ,ent in their
s~rvlce ll~e. In addit~on, when an lmpact load waR
~pplfe~, the samples of nylon wires had ~ine irregularittes
~enerated on the surface of fishin~ lines, with a result of
; reA~Iced strength, while the samples of the present
--~od~ ~nt did not involve any reduction in strength.
~5 E~periment 2
2~7~fi;8
- 23 -
In thl~ axperlment, as shown in Fig~ 3, tensile
strengt~ and knot ~trength were mea~ured for varlous
d$a~eters o$ the ~ishing line of the present embodimQnt.
Nylon wires were also employed hers for ccl"ari~on. In
Flg. 3, the marks ~, ~ represent ten~ile strength and knot
strength of the fishing line of the present e ~o~ -nt,
respectively, while the mar~s 0 and a represent those of
nylon wires. The marks 0 and ~ are for those of piano
steel wires.
As apparent from Fig. 3~ the fishing llne of the
present - ~o~ t proved to be substantially improved in
tensile strength as much as 2.1 to 3.2 time~ that of the
nylon wire~ and in knot stren~th as much as 1.7 to 2.6
tlmes that of the same. The larger the diameter o~ the
fishin~ line ber- ~S~ the graater the d~fferenc~ between
them result~.
~xperiment 3
In this experiment, as shown in Table 3, after
tha flshlng line of the present ~ nt was lmmersed in
water f~r 5 hour~, its strength, knot strength, and win~
strength were measured. As ln the prece~1 ng experiments,
nylon wlres were employed also in this experiment for
comparison. The wlnd~g strength mentioned above refers to
*he tensile rupture strength resulting when the flshlng
line i~ wound around a core wire wlth a diameter of 0.3 mm.
20~73~8
- 2~ -
Nylon wire~ having diameters o~ 78 ~m and 97 ~m were
employed for comparlson.
A~ apparent from Table 3, nylon wire , when
immersed ln water for 5 hours or more, resulted in reduced
5 strength and knot strength as compared with before
lmmerslon in water, and in breakage due to subaqueous
deterioration in terms of the win~n~ strengthO By
contrast, ln the fi~hing line of the present embodim~nt,
even after i~mersin~ into water for 5 hours, it showed 100%
strength and knot strength, and yet a sligh~ly lowered
w~n~ln~ ~trength.
[INDUSTRIAL APPLICABILITY3
Acoording to the fishing line of the pr~sent
invention, since the thlck~es~ of the synthetic resln ls
not less than 4 ~m and the stramd pitch 18 1~ to 20 times
the wire diameter, the numbers o:f curls and kinks that will
result when an impact load is a]pplied to the f~.sh1n~ llne
can b~ red-~GeA and yet the stranded wire strength will not
; be lowered e~en if there occurs any curling, thus
contributing to offering a prolonged service life of the
fishing lina.
Also, since the steel wires of the fishing line
are provided with metal plating and their ~ircumferential
faces are coated with a resln, the resulting stranded wire
25 ha~ the resin strongly bonded thereto, improving the knot
2~3~
- 25 -
strength to 50% or more of the stranded wira strength.
Thls makes it possible to solve the problem of the
convantional amorphous metal wires that they are easy to
brea~ when tied up together, of course el~ ~n~ting the need
S for u~lng any ~heS~ ve~
Furthermore, according to the fishing line of
clalm 2 of the present invention, the two-phase structured
low-carbon steel wire employed as steel wires is so
structured that 5 to 100 A processed cells re~ulting from
process~ng of cold drawin~ are arranged in one d~rection in
~lbrous manner to form a fibrous fine metallurglcal
structure with fiber intervals of 50 to 1000 A, ~uch that
it has an ultra high strength of 300 to 60~ kyf~mmZ, a~
described with the rein~orcelment e~h~nl sm mentlon~
before. Accordln~ly, it i8 poss~ble to ~ ove its tensile
: strength to a great extent as l:~ pared with con~ntional
piano steal wlres and amorphous metal wires, and to reduce
its wire diameter while a suffioient strength a~ a f~Qh~n~
line is ensured.
Yet further, since the two-phase structured low-
carbon steel wire allows an easy r~ tlon of an
en~ ly thin fishing line, the cutwater resistance
involved can be reduced, whlle ~ts high strength allow~ the
elong~tion ratio to be re~uce~ and the bite sensitivity to
b~ improved accord1ngly. Also, the anticorrosion metal
3 6 8
- 26 -
plating serve~ for preventing any subaqueous deterloration
whilo the stranded structure ln whlch a plurality of steel
wlres are stranded allows the flexiblli*y of the fishlng
llne to be improved. Thus, the resulting flshlng llne can
meet the fund~ ?ntal characteristics as a fishlng line.
:
--27--
Table 1
Sample Steel Su~ce I)iameter Resm Slrand Sttengl}l ~ot Strength Pceling Number N~unber Rema~s
wirc 2realment of lish- tbick- pitch ~ s~nglh ratio (%) of knot of ~ of curls
material ing line ness ~g~ portion tbat tbat
(mm3 ~mm) occuned oa~um d
per 250 pcr 250
mm of mm of
line line
No. 1 Piano N 0.082 0.002 16 0.95 0.5558 No 1 5 C,~,.~li.~,
wire plating example
No. 2 Piano Nl 0.082 Q008 16 Q92 0.5661 No 0 3 IDVenjOD
wirc pla2ing
~o. 3 Piano Ni 0.0&2 Q008 12 Q88 Q48 5S No 3 8 Cl"l,~di.
wite plating e~ample
No. 4 Piano N Q082 0.0~8 23 0.98 0.5960 No 5 3 G~
wire plating e~ e
No. 5 Piano No Q084 Q010 16 Q92 0.5762 Yes 3 5 cr, -~_
wire e~cample
No. 6 Piano Ni Q095 Q008 16 1.13 0.62~5 No 0 2 hlvcDtion
wirc plating
No. 7 SUS 304 Ni Q095 Q008 16 0.89 0.5258 No . O 4 Inven~on
plating
C~
~3
C~
CO
Table 2
Sasnple D~nc~r of Rcsi:Q Shalld pitch St~nded ~ Knot st~gth Impact load Number of Numbcr of
fishing line tbiclmcss st~ngt~ curls that kinlcs that
250 mm of 23C mm of
line linc
~: ' ' 0.075 10 12 Q97 59.8 0500 6 0
No. 1 ~CIass 0.2) ~(058 ~g) Q750 7 4
0925 14 17
F~ 0.075 3 12 0.963 675 0500 10 0
No. 2 (aass Q2) (0.65 ~g) Q750 8 8
~.OOQ 16 36
r.Ah~ - .,1 0.075 4 15 1-~1 61.1 0500 0 0
No. 3 (Class 0 7) (0.74 kg) Q750 6
1.000 8 9
r- -~ r ~! ~ Qo75 6 15 1.19 63.9 0.50Q 0 0
No. 4 (Class 0 ~) (0.76 kg) Q750 6 2
1.000 8 10
r ~ ~ Q075 10 16 1.20 633 050Q 0 0
No. 5 (aass ~.V (0.76 kg) 0.750 4 Q
1.000 9 6
Piano w~c f O.Q82 8 23 Q90 57.8 0500 5 0
esJn coati~g (C~ass 025) (0.52 ~g) Q750 4 4
1.000 8 15
Nylon 0.104 - - Q96 80.2 050~ 4 0
(Cla~; 0.4) (0.7~kg) Q750 9 2 ~a
0.955 6 8 O
Nylon 0.078 - - 0.469 79.9 0500 Break - _~
(C~ass 0.2) ~0375k~
' OC)
--29--
T~ble 3
Diametcr o~ g r.. ,.. ,:~ n time Strength Knot stIength Wm~ng strength
0.0~3 0 1.627 o.g~ 1.061
F.. lhofll".. t (Class 0.3)
S 1.622 0.945 1.031
- û.078 0 OA69 0375 0399
~ylon (Class 0'7)
0.449 0356
0 0.72~ ~88 0.63
- Nylon 0.097
~CI~ss 03) 5 0.710 0556
~0 0.692 0519
