[0001] This invention relates to a webbing for a belt. More particularly, the present invention
is concerned with a webbing suitable for a seat belt used for protection of drivers
and passengers of automobiles.
[0002] With the spreading of users of automobiles in recent years, the demand for seat belts
has become diversified. For example, some users of delux automobiles etc. are unsatisfied
with conventional single-color seat belts and require a seat belt comprising a combination
of different colors which exhibits a multi-color effect.
[0003] A 2/2 twill weave is widely accepted as a weave for a seat belt of automobiles. Further,
in order to maintain the tenacity required of the seat belt, the warp density is so
high that the wefts are substantially hidden behind the surface of the seat belt.
For this reason, the twill angle of the warps relative to the longitudinal direction
is very small, which makes it difficult to confirm the twill lines, so that only turnover
lines of the twill and the difference of gloss due to the reflection of light ways
are recognized.
[0004] Therefore, even if warps having a different color are threaded into a 2/2 twill weave
having a very high warp density, only a simple stripe pattern can be formed on the
surface of the weave. In other words, it is difficult to form a pattern having noticeable
portions having a different color diagonal to the longitudinal direction of the belt.
This rendered it impossible to sufficiently comply with the above-described diversification
of the needs of users.
[0005] An object of the present invention is to provide a webbing for a belt which can develop
various patterns comprising portions having a different color noticeably arranged
at the diagonal direction of the webbing even in a weave of a 2/2 twill weave having
a very high warp density.
[0006] Another object of the present invention is to provide a webbing for a seat belt having
a weave pattern which can sufficiently comply with the diversification of the tastes
of users.
[0007] The webbing for a belt of the present invention for attaining the above objects basically
comprises a weave of 2/2 twill having such a high warp density that the wefts are
substantially hidden behind the surface of the webbing. In the above-described weave
of 2/2 twill, the webbing of the present invention is characterized in that said warp
comprises at least two kinds of yarns different from each other in the color and said
at least two kinds of yarns are in an alternate warp threading arrangement through
two or more rows of yarns adjacent thereto having the same color so that said warp
threading arrangement forms a pattern portion which allows a portion having a different
color to appear diagonally to the longitudinal direction of the belt.
[0008] Particularly, the webbing for use in a seat belt is characterized in that said plurality
of yarns having different colors comprise a spin-dyed yarn and a non-spin-dyed yarn
each having a multifilament yarn structure and the difference in the fineness and
strength between said spin-dyed yarn and said non-spin-dyed yarn is 10% or less.
[0009] Other objects of the present invention will be apparent from the following description
of the preferred embodiments with reference to the accompanying drawings.
Figs. 1 to 13 are drawings of the weaving of the webbing for a belt according to the
present invention; and
Figs. 14 to 18 are plan views of belts each comprising a webbing according to the
present invention.
[0010] In the webbing for a belt according to the present invention, there is no particular
limitation with respect to the plurality of yarns having different colors for use
in the warp as far as they comprise a combination of yarns having different colors.
For example, the combination may be any of a combination of a spin-dyed yarn with
a non-spin-dyed yarn, a combination of a dyed yarn with an undyed yarn, a combination
of spin-dyed yarns having different colors, a combination of dyed yarns having different
colors, and a combination of a spin-dyed yarn with a dyed yarn. Further, the warp
yarn may be in the form of a multifilament yarn or a spun yarn.
[0011] However, in the case of a webbing for a seat belt, it is preferred that the above-described
at least two kinds of yarns comprise a combination of a spin-dyed yarn with a non-spin-dyed
yarn. Further, the yarn is preferably in the form of a multifilament yarn. It is preferred
that the dyed yarn be used for applications, e.g., suspending belts for sporting bags,
which do not rather require very high tenacity. This is because the dyed yarn is passed
through various steps, such as draw twisting, hank reeling, dyeing, and hank winding,
and therefore exhibits a greater tendency to cause the lowering in the tenacity than
those of the spin-dyed yarn and the non-spin-dyed yarn in a natural form. When the
dyed yarn is used for a webbing for a seat belt, it is necessary to increase the number
of the yarns in order to compensate for the lowering in the tenacity. However, the
use of a large amount of the yarn brings about not only an increase in the cost but
also an increase in the thickness of the belt which makes it difficult to smoothly
take the belt in and out of a retractor.
[0012] In the present invention, the term "spin-dyed yarn" is intended to mean a yarn which
has been dyed by blending a raw resin with a pigment or a dye prior to the spinning
of the raw resin into a yarn, while the term "dyed yarn" is intended to mean a yarn
which has been dyed after the spinning of a raw resin into a yarn. There is no particular
limitation with respect to the color applied to these spin-dyed yarn and dyed yarn.
However, the dyeing in black, light brown, blue or the like is preferable.
[0013] When a webbing for a seat belt is manufactured by a combination of the above-described
spin-dyed yarn and non-spin-dyed yarn each having a multifilament yarn structure,
the difference in the fineness and strength between the spin-dyed yarn and the non-spin-dyed
yarn is preferably 10% or less, more preferably 6% or less. Further, it is preferred
that the difference in the breaking elongation between the spin-dyed yarn and the
non-spin-dyed yarn be preferably 10% or less.
[0014] In the webbing for a belt according to the present invention, as described above,
the plurality of yarns having different colors are used as the warp, and these are
woven into a weave having a 2/2 twill. In the weave having a 2/2 twill, the warp density
is so high that the wefts are substantially hidden behind the surface of the webbing.
When the plurality of yarns having different colors are subjected to warp threading
arrangement in such a high warp density, two or more rows of yarns having the same
color and adjacent to each other are arranged alternately with a yarn having a different
color. This warp threading arrangement forms a pattern portion which allows a portion
having a different color to appear diagonally to the longitudinal direction of the
belt. In the present invention, it is a matter of course that a single row of yarn
may coexist in these arrangements as far as these arrangements meet the above-described
requirement that yarns having the same color be arranged in two or more rows adjacent
to each other.
[0015] Further, in the present invention, it is more preferable that the above-described
warp threading arrangement be conducted so that yarns are regularly arranged bilaterally
symmetrically with respect to one yarn arranged in the center. The above-described
regular arrangements which are bilaterally symmetrical enable the formation of a pattern
having a pattern weaving portion which allows a portion having a different color to
clearly appear diagonally to the longitudinal direction of the belt, e.g., one-thread
or two-thread yarn bonds pattern, zig-zag pattern, chessboard pattern, and opposing
triangular pattern which will be described later.
[0016] In the above-described 2/2 twill weave, when the twill line pattern weaving portions
except for the turnover portions of the twill line pattern are regularly arranged
in units of three, five, six, seven, or nine yarns in terms of the number of the warps
having the same color and adjacent to each other in the order of the warp threading,
a twill pattern, such as pointed twill having a twill line angle of about 20°, can
be formed in spite of an actual weaving twill line angle of about 7°.
[0017] The weave patterns according to the present invention will now be described with
reference to the attached drawings. For simplification of the explanation, reference
will be made to an example in which a spin-dyed yarn B having a multifilament structure
and a non-spin-dyed yarn N having a multifilament structure are used.
[0018] Fig. 1 shows the weaving of a 2/2 twill weave having one-thread bonds pattern. As
shown in the drawing, the spin-dyed yarn B and the non-spin-dyed yarn N are arranged
in the order of the warp threading of the 2/2 twill weave as follows: four rows of
the spin-dyed yarn B, two rows of the non-spin-dyed yarn N, a row of the spin-dyed
yarn B, two rows of the non-spin-dyed yarn N, a row of the spin-dyed yarn B, two rows
of the non-spin-dyed yarn N, and four rows of the spin-dyed yarn B (i.e., B4, N2,
B1, N2, B1, N2, B4). With respect to this arrangement, it is apparent from the drawing
that a row of B, two rows of N, and four rows of B are regularly arranged in that
order on both sides of two central rows of N indicated by a double arrow and bilaterally
symmetrically with respect to the two central rows of N. When a webbing is manufactured
in the above-described warp threading arrangement so as to have such a high warp density
that the wefts are hidden behind the surface of the webbing, a belt comprising this
webbing has a distinct one thread bonds pattern as designated by numeral 10 in Fig.
14.
[0019] Although, in Fig. 1, the twill lines run in the lower right direction, they may run
in the lower left direction as shown in Fig. 2. In this case, the diagonal portion
having a different color appears as a diagonal running in the lower right direction
as opposed to the one-thread bonds pattern 10 shown in Fig. 14.
[0020] Fig. 3 shows the weaving of a two-thread bonds pattern formed by repeating two units
of the warp threading arrangement shown in Table 1.
[0021] Specifically, the four rows of the spin-dyed yarns arranged at the end portion of
Fig. 1 are arranged at the central portion (position indicated by a double arrow),
followed by the other arrangements symmetrical bilaterally with respect to this central
portion. Further, in this warp arrangement, the two rows of the non-spin-dyed yarns
N indicated by a single arrow in each unit arrangement serve as the center of symmetry
of the unit arrangement. When this warp threading arrangement is conducted in such
a high warp density that the wefts are hidden behind the surface of the webbing, a
distinct two-threads bonds pattern as designated by numeral 11 in Fig. 14 is formed.
[0022] Fig. 4 shows the weaving of a 2/2 twill weave which allows a double zig-zag pattern
to appear. In this 2/2 twill weave, a row of the non-spin-dyed yarns N indicated by
a double arrow is arranged at the central portion, and the following arrangements
are made in the order of the warp threading on both the right and left sides thereof
symmetrically with respect to the central row of the non-spin-dyed yarns N: a row
of the spin-dyed yarn B, two rows of the non-spin dyed yarn N, two rows of the spin-dyed
yarn B, a row of the non-spin-dyed yarn N, five rows of the spin-dyed yarn B, a row
of the non-spin-dyed yarn N, two rows of the spin-dyed yarn B, two rows of the non-spin-dyed
yarn N, and a row of the spin-dyed row B. Further, in the unit arrangements respectively
on the right and left sides thereof, the five rows of the spin-dyed yarns B serve
as the center of symmetry of each unit arrangement.
[0023] That is, the overall warp threading arrangement is as follows: B1, N2, B2, N1, B5,
N1, B2, N2, B1, N1, B1, N2, B2, N1, B5, N1, B2, N2, B1. When a belt is manufactured
by conducting this warp threading arrangement in such a high warp density that the
wefts are hidden behind the surface of the belt, a distinct zig-zag pattern as designated
by numeral 12 in Fig. 15 is obtained.
[0024] Fig. 5 shows a view of the weaving of a 2/2 twill weave for forming an opposing triangular
pattern. In this 2/2 twill weave, five rows of the non-spin-dyed yarn N indicated
by a double arrow are arranged at the central portion, and the following arrangements
are made in the order of the warp threading on both the right and left sides thereof
so as to attain a symmetrical relationship with respect to the central rows of the
non-spin-dyed yarns: a row of the spin-dyed yarn B, two rows of the non-spin-dyed
yarn N, two rows of the spin-dyed yarn B, two rows of the non-spin-dyed yarn N, and
three rows of the spin-dyed yarn B. That is, the overall warp threading arrangement
is as follows: B3, N1, B2, N2, B1, N5, B1, N2, B2, N1, B3.
[0025] Fig. 6 shows a drawing of the weaving of a 2/2 twill weave for forming a chessboard
pattern. In this 2/2 twill weave, four rows of the non-spin-dyed yarn N indicated
by a double arrow are arranged at the central portion, and the following arrangements
are made in the order of the warp threading on both the right and left sides thereof
so as to attain a symmetrical relationship with respect to the central rows of the
non-spin-dyed yarns: two rows of the spin-dyed yarn B, two rows of the non-spin-dyed
yarn N, two rows of the spin-dyed yarn B, two rows of the non-spin-dyed yarn N, two
rows of the spin-dyed yarn B, two rows of the non-spin-dyed yarn N, two rows of the
spin-dyed yarn N, two rows of the non-spin-dyed yarn N, and two rows of the spin-dyed
yarn B. Further, in the unit arrangements respectively on the right and left sides
thereof, the two rows of the spin-dyed yarns B serve as the center of symmetry of
each unit arrangement.
[0026] That is, the overall warp threading arrangement is as follows: B2, N2, B2, N2, B2,
N2, B2, N2, B2, N4, B2, N2, B2, N2, B2, N2, B2, N2, B2. When a belt is manufactured
by conducting this warp threading arrangement in such a high density that the wefts
are hidden behind the surface of the belt, a distinct chessboard pattern as designated
by numeral 14 in Fig. 16 is obtained.
[0027] In the present invention, it is preferred that the above-described weave patterns
each having a diagonal portion of a different color be formed on both end portions
of the belt as shown in Figs. 14 to 16. However, these patterns may be formed over
the entire width of the belt by repeating the above described unit arrangements. Further,
when the weave pattern is arranged over the entire width, the twill lines may be unidirectional.
Alternatively, the direction of the twill lines may be changed in the course of the
weaving to form a symmetrical pattern.
[0028] Figs. 7 to 13 are each a drawing of the weaving for forming a twill pattern, such
as pointed twill. In all the cases, the weave is 2/2 twill, and the spin-dyed yarn
B and the non-spin-dyed yarn N are regularly arranged in the order of the warp threading
in units of three yarns (Fig. 7), five yarns (Figs. 8 and 9), six yarns (Fig. 10),
seven yarns (Fig. 11), or nine yarns (Figs. 12 and 13) exclusive of turnover portions
of the twill lines. The weaving in the units of a plurality of warps enables the formation
of intermittent twill pattern manifesting portions of the spin-dyed yarns B through
which a line L can be drawn. That is, the twill line having a gentle slope can be
observed along the line L.
[0029] More particularly, in Fig. 7, units of three yarns, i.e., a spin-dyed yarn B and
two non-spin-dyed yarns N are regularly arranged, and the angle, ϑ, of the twill line
based on the line L relative to the longitudinal direction of the webbing is about
20°.
[0030] In Fig. 8, units of five yarns, i.e., a spin-dyed yarn B and four non-spin-dyed yarns
are arranged, while in Fig. 9, units of five yarns, i.e., two spin-dyed yarns B and
three non-spin-dyed yarns N are arranged. In each case, the angle, ϑ, of the twill
line, based on the line L, relative to the longitudinal direction of the webbing is
about 31°.
[0031] In Fig. 10, units of six yarns, i.e., two spin-dyed yarns B and four non-spin-dyed
yarns N are arranged, and the angle, ϑ, of the twill line, based on the line L, relative
to the longitudinal direction of the webbing is about 20°.
[0032] In Fig. 11, units of seven yarns, i.e., a spin-dyed yarn B and six non-spin-dyed
yarns N are arranged, and the angle, ϑ, of the twill line, based on the line L, relative
to the longitudinal direction of the webbing is about 41°.
[0033] In Fig. 12, units of nine yarns, i.e., a spin-dyed yarn B and eight non-spin-dyed
yarns N are regularly arranged, while in Fig. 13, units of nine yarns, i.e., a spin-dyed
yarn B, three non-spin-dyed yarns N, a spin-dyed yarn B, and four non-spin-dyed yarns
N in that order are regularly arranged. In each case, the angle, ϑ, of the twill line,
based on the line L, relative to the longitudinal direction of the webbing is about
48°.
[0034] The above-described webbing of the present invention can be used not only for seat
belts but also for general applications such as fashion tape belts.
Example 1:
[0035] A polyester pellet having a high degree of polymerization which was dyed black was
melt spun, followed by drawing, thereby preparing a spin-dyed yarn B of 1260 deniers
and 108 filaments having a tenacity of 8.68 g/d, a breaking elongation of 12.9%, and
a dry heat shrinkage of 8.5%. Separately, an uncolored polyester pellet having a high
degree of polymerization was melt spun, followed by drawing, thereby preparing a non-spin-dyed
yarn N of 1260 deniers and 108 filaments having a tenacity of 8.93 g/d, a breaking
elongation of 13.8%. and a dry heat shrinkage of 9.0%.
[0036] 321 yarns in total of the spin-dyed yarns B and the non-spin-dyed yarns N were used
as the warp. On the other hand, non-spin-dyed polyester filament yarns of 750 deniers
and 72 filaments were used as the weft and picked in 22 picks/30 mm, thereby weaving
a webbing for a belt comprising a 2/2 twill weave having a width of 50 mm. In weaving
this webbing for a belt, the spin-dyed yarn B and the non-spin-dyed yarn N used as
the warps were arranged on both side regions in such a manner that in the outer region,
they were arranged into a weave as shown in Fig. 3, while in the inner region, they
were arranged into a weave as shown in Fig. 1. The webbing thus obtained was then
dyed grey with a continuous dyeing machine. Thus, there was obtained a belt having
distinct and beautiful two-thread bonds figures and one-thread bonds figures having
a black color on a grey ground as shown in Fig. 14.
[0037] A seat belt for a passenger car was manufactured from this webbing and then subjected
to webbing tests with respect to seat belts of automobiles prescribed in JIS D 4604.
As a result, it was found that the seat belt had a tenacity meeting all the requirements
for performance prescribed in JIS. The thickness of the webbing was not different
from those of the current webbings. Therefore, it was possible to accommodate the
belt within the current retractor. Further, the belt could smoothly be taken in and
out of the retractor.
Example 2:
[0038] 66 yarns of black spin-dyed yarns and 256 yarns of non-spin-dyed yarns of the same
kinds as those used in Example 1 were used as the warps, and non-spin dyed polyester
filament yarns of 750 deniers and 72 filaments were used as the wefts in 24 picks/30
mm to form a 2/2 twill weave of 3 crests (6 panels). The warps were arranged in units
of five yarns, i.e., a black spin-dyed yarn and four non-spin-dyed yarns in the order
of the threading, and 11 black spin-dyed yarns were used in a panel. Thus, a webbing
was woven. The webbing thus obtained was as shown in Fig. 17, i.e., had a twill pattern
like a pointed twill. In this pattern, 11 black color lines per panel were observed.
Although the lines were intermittent, the twill lines having an angle of about 31°
were clearly observed.
Example 3:
[0039] 93 yarns of black spin-dyed yarns and 183 yarns of non-spin-dyed yarns of the same
kinds as those of Examples 1 and 2 were used as the warps, and the same non-spin dyed
polyester filament yarns as those of Example 2 were used as the wefts in 23 picks/30
mm to form a 2/2 twill weave. The warps were arranged in units of three yarns, i.e.,
a black spin-dyed yarn and two non-spin-dyed yarns in the order of the threading.
Thus, a webbing was woven. The webbing thus obtained was as shown in Fig. 18, i.e.,
had a twill pattern like a pointed twill.
[0040] As described above, in the webbing of the present invention, the warp threading arrangement
is conducted so that two or more rows of yarns adjacent thereto having the same color
are present. This arrangement enables the formation of a pattern in which a portion
having a different color distinctly appears diagonally to the longitudinal direction
of the belt even in a weave of a 2/2 twill having a very high warp density.