Technical Field
[0001] The present invention relates to a brassiere, and, more particularly, to a brassiere
that suppresses movement of breasts during exercise and prevents chafing of a skin
of a human body. The present invention is suitably applied to a sports brassiere and
the like.
Background Art
[0002] Suppression of movement of breasts during exercise is required as an important function
of sports brassieres, and various sports brassieres each having a movement suppressing
function have been known conventionally (Patent Literatures I to 4).
[0003] Such conventional sports brassieres are common in increasing the compressions (compression
pressures applied by the brassiere in wear) of cup parts and an under belt and tightening
breasts, to thereby suppress movement of the breasts. Such conventional sports brassieres
are also common in that shoulder straps are attached to a brassiere main body at a
substantially right angle to an under-bust line.
[0004] Fig. 11 illustrates an example of a conventionally known sports brassiere. This brassiere
includes: a brassiere main body 11 made of a front body for covering a chest and a
back body for covering a back; and right and left shoulder straps 12 provided between
the upper end edges of the front body and the back body. An under belt 14 is provided
at the lower end edge of the brassiere main body 11 with the intermediation of an
under-bust line 13.
[0005] Bust points 16 are respectively positioned in the right and left of the front body
of the brassiere main body 11, and a given range that covers a breast about each of
the bust points 16 is referred to as a cup part 17. Pads are fitted as appropriate
to the rear surface of the brassiere main body 11 with reference to the positions
of the bust points 16. An attachment angle θ of the shoulder straps 12 to the brassiere
main body 11 is approximately 90°.
[0006] According to the conventional sports brassiere configured as described above, the
entirety thereof is brought into close contact with a wearer body, the compression
of the cup parts 17 and portions therearound is increased by flexibility of the material
thereof, and the breasts are compressed to be thereby suppressed from moving.
[0007] Meanwhile, Patent Literature 4 discloses a front-open type brassiere, in which parts
of shoulder straps are in contact with the insides of cup parts, and the lower ends
of the shoulder straps reach side parts of the under belt, respectively.
[0008] Note that, for ease of the following description, names of other parts of the brassiere
than those described above are defined in the following manner.
[0009] Inferior point 19 of bust point: a point on the under-bust line 13, of a vertical
line drawn from the bust point 16
[0010] Inferior point 20 of anterior axilla point: a point on the under-bust line 13, of
an anterior axillary line 21
[0011] Side part 22 of under belt: a portion of the under belt 14 between the inferior point
19 of the bust point and the inferior point 20 of the anterior axilla point
[0012] Front part 23 of under belt: a front central portion of the under belt 14 between
the right and left inferior points 19 of the bust points
Citation List
Patent Literature
[0013]
Patent Literature 1: Japanese Patent Application Laid-Open No. 2003-221705
Patent Literature 2: Japanese Patent Application Laid-Open No. 2006-104613
Patent Literature 3: Japanese Patent Application Laid-Open No. 2009-133027
Patent Literature 4: US 5378192 A (the 6th line to the 8th line in the first column, the 18th line in the third column to the 38th line in the fourth column, and Figs. 3 and 6)
Summary of Invention
Technical Problem
[0014] Movement of breasts during exercise provokes extension and damage of Cooper's ligaments
inside of the breasts, and causes sagging of the breasts. If the compression of the
cup parts or the portions therearound is increased to suppress the movement of the
breasts as in the conventional sports brassieres, a heart, lungs, and internal organs
are compressed, which is not desirable. Further, if the compression of the cup parts
or the under belt is excessive, the positions and forms of various parts of the internal
organs may be unfavorably changed.
[0015] Moreover, in the conventional structure, a wide region ranging over the cup parts
17 and the portions therearound is tightened, and the attachment angle θ of the shoulder
straps 12 to the brassiere main body 11 is substantially 90°. Hence, a large portion
of the brassiere in the conventional structure overlaps with a large skin strain area
30 during exercise. For this reason, chafing of a skin is likely to occur, and the
brassiere main body 11 is likely to be slid upward in the course of the exercise.
[0016] Similarly in the brassiere described in Patent Literature 4, the shoulder straps
only pass through extremely small portions inside of the cup parts. Hence, an effect
of obliquely holding breasts is small, and almost no effect of suppressing movement
of the breasts is produced.
[0017] Note that the large skin strain area 30 refers to a triangular range surrounded by
points X1, X2, and X3 in the drawings. X1 denotes an acromion, X2 denotes an anterior
axilla point, and X3 denotes a point at 3/5 of a distance L from the anterior axilla
point X2, the distance L being a distance between: the anterior axilla point X2; and
an intersection point X4 between a horizontal line X from the anterior axilla point
and a midline Y.
[0018] In view of the above, the present invention has an object to produce an effect of
suppressing movement of breasts while limiting a range in which the breasts are compressed,
to thereby reduce compression on various parts of internal organs such as a heart
and lungs, the breasts, and the like and, at the same time, eliminate an overlap range
with a large skin strain area during exercise, thus preventing chafing of a skin.
Solution to Problem
[0019] In order to solve the above-mentioned problems, the present invention provides a
brassiere including: a brassiere main body made of a front body for covering a chest
and a back body for covering a back; right and left shoulder straps provided between
upper end edges of the front body and the back body; an under belt that is provided
at a lower end edge of the brassiere main body with an intermediation of an under-bust
line; and a pair of right and left cup parts provided in the front body. An attachment
angle of the shoulder straps to the brassiere main body is defined by such an angle
that an intermediate line of each shoulder strap extends to pass through a central
portion of the cup part at a diagonal position of the shoulder strap and reach a range
including an inferior point of a bust point and an inferior point of an anterior axilla
point on the under-bust line.
[0020] In the present invention, an outer circumferential circle of the cup part is defined
by a circle having a radius that is a distance between the bust point in a center
of the cup part and the inferior point of the bust point on the under-bust line, and
a range of the central portion of the cup part is defined by a concentric reference
circle having a radius that is 0.6 times the radius of the cup part.
[0021] Specifically, an inclination angle of the intermediate line to the under-bust line
falls within a range between a largest inclination angle θ1 defined below in (1) and
a smallest inclination angle θ2 defined below in (2):
- (1) the largest inclination angle θ1 is defined by such an angle that the intermediate
line that passes on an inner side of the bust point of the cup part at the diagonal
position extends to come into contact with the reference circle or pass through an
inside of the reference circle and reach the range including the inferior point of
the bust point and the inferior point of the anterior axilla point on the under-bust
line; and
- (2) the smallest inclination angle θ2 is defined by such an angle that the intermediate
line that passes on an outer side of the bust point of the cup part at the diagonal
position or passes through the bust point extends to come into contact with the reference
circle or pass through the inside of the reference circle and reach the range including
the inferior point of the bust point and the inferior point of the anterior axilla
point on the under-bust line.
[0022] Alternatively, an inclination angle of the intermediate line to the under-bust line
may fall within a range between a largest inclination angle θ1 defined below in (1)
and a smallest inclination angle θ2 defined below in (2):
- (1) the largest inclination angle θ1 is defined by such an angle that the intermediate
line that passes on an inner side of the bust point of the cup part at the diagonal
position extends to come into contact with the reference circle or pass through an
inside of the reference circle and reach the inferior point of the bust point on the
under-bust line; and
- (2) the smallest inclination angle θ2 is defined by such an angle that the intermediate
line that passes on the inner side of the bust point of the cup part at the diagonal
position extends to come into contact with the reference circle or pass through the
inside of the reference circle and reach the inferior point of the anterior axilla
point on the under-bust line.
[0023] Further, a medial reference line that passes through a medial point of a smallest-width
portion of the shoulder strap and is parallel to the intermediate line that defines
the largest inclination angle θ1 passes through the inside of the reference circle
along this intermediate line, and a lateral reference line that passes through a lateral
point of the smallest-width portion of the shoulder strap and is parallel to the intermediate
line that defines the smallest inclination angle θ2 passes through the inside of the
reference circle along this intermediate line.
[0024] Further, an armhole is formed between a lateral edge of each shoulder strap and the
upper end edge of the front body, and a maximum curvature point of the armhole is
set on an inner side of a point at 3/5 of a distance from the anterior axilla point
to a midline, on a horizontal line from the anterior axilla point.
[0025] The attachment angle of the shoulder straps to the brassiere main body is defined
as described above, whereby an obliquely acting tension is partially applied to each
side part of the under belt across the cup part located at the diagonal position of
each shoulder strap (the cup part at the diagonal position with respect to each shoulder
strap), with the result that movement of breasts is suppressed.
[0026] The attachment angle of the shoulder straps is more greatly inclined in a direction
in which the lower end thereof approaches the midline of a wearer body, compared with
conventional cases. Accordingly, an armhole can be formed so as to be greatly curved
along each shoulder strap thus configured, and an overlap with a large skin strain
area can be avoided.
Advantageous Effects of Invention
[0027] As described above, the brassiere of the present invention can locally increase the
compression of the side parts of the under belt at the respective diagonal positions
by means of the tensions of the shoulder straps, to thereby suppress movement of breasts.
Although the compression of the side parts of the under belt is increased, the compression
of the under-chest part does not need to be increased, and the compression applied
to the breasts is partial. Hence, compression on a heart, lungs, and various parts
of internal organs is reduced.
[0028] Further, the armholes can be formed at positions that do not overlap with the large
skin strain area. Hence, chafing of a skin is prevented, the degree of freedom in
motion such as an arm swing is increased, and the brassiere main body is prevented
from sliding up due to a motion.
[0029] Accordingly, the brassiere of the present invention is suitably applied to sports.
Brief Description of Drawings
[0030]
Fig. 1A is a front view illustrating a wear state of a sample a in Experiment 1.
Fig. 1B is a front view illustrating a wear state of a sample b in Experiment 1.
Fig. 1C is a front view illustrating a wear state of a sample c in Experiment 1.
Fig. 2A shows a movement track of a right breast.
Fig. 2B shows a movement track of a left breast.
Fig. 3A is a graph showing a relation between an under-armpit part compression and
an up-down movement.
Fig. 3B is a graph showing a relation between the under-armpit part compression and
a right-left movement.
Fig. 4A is a graph showing a relation between an under-chest part compression and
the up-down movement.
Fig. 4B is a graph showing a relation between the under-chest part compression and
the right-left movement.
Fig. 5A is a front view illustrating a wear state of a sample A in Experiment 2.
Fig. 5B is a front view illustrating a wear state of a sample B in Experiment 2.
Fig. 5C is a front view illustrating a wear state of a sample C in Experiment 2.
Fig. 5D is a front view illustrating a wear state of a sample D in Experiment 2.
Fig. 5E is a front view illustrating a wear state of a sample E in Experiment 2.
Fig. 6 is a graph showing measurement results of the under-armpit part compression.
Fig. 7A is a graph showing measurement results of the up-down movement.
Fig. 7B is a graph showing measurement results of the right-left movement.
Fig. 8 is a graph showing measurement results of the under-chest part compression.
Fig. 9 is a front view illustrating a brassiere in Embodiment 1.
Fig. 10A is a front view illustrating a wear state of the brassiere in Embodiment
1.
Fig. 10B is a rear view of Fig. 10A.
Fig. 11 is a front view illustrating a wear state in a conventional example.
Description of Embodiments
[0031] Experiments from conceiving of the present invention to completion thereof are first
described as [Experiment 1] and [Experiment 2], and a specific embodiment of the present
invention is then described as [Embodiment 1].
[Experiment 1]
1. Purpose of Experiment
[0032] The experiment is intended to know a relation between: movement of breasts; and an
under-armpit part compression and an under-chest part compression.
2. Samples
[0033] Three types of sports brassieres of samples a to c illustrated in Fig. 1A to Fig.
1C are used as the samples. Among these samples, the position of an under belt 21
is lowest for the sample a, at a middle height for the sample b, and highest for the
sample c, in a conventional sports brassiere (see Fig. 1). An attachment angle θ of
shoulder straps 12 is approximately 90° for all the samples. A neck line 25 is circular
for the samples a and b, and angular for the sample c.
3. Contents of Experiment
[0034] The same woman who wore the samples a to c one after another ran at 9 km/h on a treadmill
in the state where markers were respectively added to bust points 16, and how the
markers moved at that time was measured using a three-dimensional motion analysis
system (VICON), on the basis of a fossa jugularis (an intersection point between:
a straight line connecting upper sternal ends of right and left collarbones; and a
midline) as a reference point.
4. Experiment Results
(1) Movement Track
[0035] The movement track for the sample a is shown in Fig. 2A (right breast) and Fig. 2B
(left breast). Although the amplitude was different in the other samples b and c,
the movement tracks for the samples b and c also showed such tracks (substantially
two-leaf forms) as those in Figs. 2A and 2B as a whole form. In this track, a node
J of the movement exists in its central portion, and amplitude parts W1 and W2 extend
obliquely upward in a two-leaf pattern on both the right and left sides of the node
J.
(2) Relation between Under-armpit Part Compression and Movement
[0036] Fig. 3A shows a relation between the under-armpit part compression and an up-down
movement for the samples a to c, and Fig. 3B shows a relation between the under-armpit
part compression and a right-left movement for the samples a to c.
(3) Relation between Under-chest Part Compression and Movement
[0037] Fig. 4A shows a relation between the under-chest part compression and the up-down
movement for the samples a to c, and Fig. 4B shows a relation between the under-chest
part compression and the right-left movement for the samples a to c.
5. Considerations
[0038] (1) The experiment results showed that, for the sample a, both the under-armpit part
compression and the under-chest part compression were largest, and the amplitude was
smallest (in other words, a movement suppressing effect was highest).
[0039] Considering the positions at which the breasts are compressed, it is apparent that
the under-chest part compression is more likely to cause compression on a heart, lungs,
and various parts of internal organs, compared with the under-armpit part compression.
[0040] In contrast, the under-armpit part compression is less likely to cause compression
on the internal organs. If the attachment angle of the shoulder straps 12 is inclined,
the tensions of the shoulder straps 12 can be applied to under-armpit parts, and the
under-armpit part compression can be locally increased.
[0041] The following idea is obtained on the basis of the above considerations. That is,
the attachment angle θ of the shoulder straps 12 is appropriately set, whereby the
tensions of the shoulder straps 12 are respectively applied so as to obliquely pass
through cup parts 17 at the diagonal positions of the shoulder straps 12 to reach
the under-armpit parts. As a result, the under-armpit part compression can be increased,
and the movement of the breasts can be effectively suppressed, while compression on
the heart, lungs, and the like is avoided.
[0042] Note that the following measures can be conceived as a comparison with the above-mentioned
idea. That is, the attachment angle θ of the shoulder straps 12 is appropriately set,
whereby the tensions of the shoulder straps 12 are concentrated on an under-chest
part, and the under-chest part compression is locally increased. However, the attachment
angle θ in this case is relatively large, and hence the tensions of the shoulder straps
12 cannot be effectively applied so as to respectively increase the compressions of
the side parts of the under belt at the diagonal positions.
[0043] (2) Because the attachment angle of the shoulder straps 12 is substantially 90° for
all the samples a to c, armhole lines 24 cannot be set to be large. Hence, an overlap
range with a large skin strain area 30 (see Fig. 11) during exercise is large, and
chafing of a skin may occur in the large range. Further, a brassiere main body 11
tends to slide up together with skin expansion/contraction.
[Experiment 2]
1. Purpose of Experiment
[0044] Experiment 2 is intended to examine a relation among the attachment angle θ of the
shoulder straps 12, the magnitude of the under-armpit part compression, and movement
suppression, in order to embody the idea obtained by Experiment 1 and check technical
effects thereof.
2. Samples
[0045] Fig. 5A to Fig. 5E illustrate samples A to E, respectively. The basic configuration
of each sample is similar to that in a conventional example (see Fig. 11), but is
different in the attachment angle θ of the shoulder straps 12 in the following manner.
The angle θ is described using modes of intermediate lines 18 of the shoulder straps
12.
[0046] Sample A: The intermediate lines 18 obliquely extend across central portions of the
cup parts 17 at the diagonal positions to reach inferior points 20 of anterior axilla
points, respectively.
[0047] Sample B: The intermediate lines 18 extend to reach the center of the under-chest
part on an under-bust line 13.
[0048] Sample C: The intermediate lines 18 extend to reach central portions of anterior
axillary lines 21, respectively.
[0049] Sample D: Similarly to the brassiere disclosed in Patent Literature 4, parts of the
shoulder straps are in contact with the insides of the cup parts, and the lower ends
of the shoulder straps reach the side parts of the under belt, respectively. The intermediate
lines 18 extend to reach portions of the under-chest part near inferior points 19
of the bust points at the diagonal positions, respectively.
[0050] Sample E: The intermediate lines 18 extend to reach portions of the under-armpit
parts immediately therebelow, respectively.
3. Contents of Experiment
[0051] The under-armpit part compression was measured by putting the samples A to E one
after another on the same mannequin that allows compression measurement. Further,
the same woman wore the samples A and E, and it was measured how the markers moved
during running on the treadmill under the same conditions as those in Experiment 1,
whereby the up-down amplitudes and the right-left amplitudes were obtained.
4. Experiment Results
[0052] The under-armpit part compressions for the samples A to E are shown in Fig. 6. The
up-down amplitudes and the right-left amplitudes therefor are shown in Fig. 7A and
Fig. 7B, respectively. The under-chest part compressions therefor are shown in Fig.
8.
5. Considerations
[0053] With regard to a relation between the modes of the intermediate lines 18, that is,
the attachment angle θ of the shoulder straps 12 and the under-armpit part compression,
if the angle θ is relatively large (the samples B, D, and E) and if the angle θ is
relatively small (the sample C), the under-armpit part compression is relatively low
(see Fig. 6), and the sample A has a superior suppressing effect in the comparison
of the samples A and E. For the samples B to E, the intermediate lines 18 of the shoulder
straps 12 respectively extend to reach positions away from the side parts 22 of the
under belt, and do not reach the side parts 22. This can be considered as a reason
why the under-armpit part compression is relatively low.
[0054] In contrast, the sample A is remarkably different from the samples B, C, and D in
that the intermediate lines 18 obliquely extend across the centers of the cup parts
17 at the diagonal positions to reach the side parts 22 of the under belt, respectively.
[0055] In the case of the sample A, even if the under-armpit part compression is increased
to some degree, positionally, an influence on the heart, lungs, and the like is small.
Further, the range in which the breasts are compressed is limited to a local range
along the intermediate lines 18, and the entire breasts are not compressed. Further,
the armhole lines 24 can be greatly curved inward along the inclinations of the shoulder
straps 12, and hence an overlap with the large skin strain area 30 can be easily avoided.
[0056] For more information, measurement results of the under-chest compressions for the
samples A and E are shown in Fig. 8. The samples A and E exhibited similar low values.
[0057] Note that Experiment 2 is described in the state where on-shoulder portions of the
shoulder straps 12 are fixed to given positions, but the positions are each set as
appropriate within a shoulder width range.
[Embodiment 1]
[0058] It is examined as to which range is preferable for the attachment angle θ of the
shoulder straps 12 in the case where a sports brassiere having a preferable structure
is manufactured on the basis of Experiment 1 and Experiment 2 described above.
[0059] In Experiment 1 and Experiment 2, the tension of each shoulder strap 12 is represented
by one intermediate line 18, but the shoulder strap 12 actually has a given width,
a belt of spreading tension corresponding to the given width is applied and locally
increases the compression of the side part 22 of the under belt through the cup part
17.
[0060] Accordingly, as illustrated in Fig. 9, the intermediate line 18 is defined by a line
obtained by connecting an intermediate point c1 of a smallest-width portion (in the
drawings, the uppermost end) of the shoulder strap 12 to an intermediate point c2
of a width at a position that is away from the smallest-width portion by a given distance
in the length direction. The tension that is distributed along the intermediate line
18 in a belt-like pattern having the width of the smallest-width portion is considered
to locally increase the compression of the side part 22 of the under belt.
[0061] Considering the results of Experiment 2, if the intermediate line 18 is excessively
away from the central portion of the cup part 17, that is, the bust point 16, a movement
suppressing effect is impaired. Accordingly, in order to exclude, from the targets,
the intermediate lines 18 that pass through portions away from the central portion
by a given distance or more, a concentric circle having a radius that is 0.6 times
a radius a of the cup part 17 is set as a reference circle 26. The value of 0.6 times
is empirically determined considering that the tensions of the shoulder straps 12
can reach the movement track ranges in Fig. 2A and Fig. 2B.
[0062] On the basis of the above considerations, a largest attachment angle θ1 and a smallest
attachment angle θ2 of the shoulder straps 12 can be set in the following manner.
Note that, for ease of description, the following terms are defined.
· Medial reference line 27: a line that passes through a medial point d1 of the smallest-width
portion of the shoulder strap 12 and is parallel to the intermediate line 18
· Lateral reference line 28: a line that passes through a lateral point e1 of the
smallest-width portion of the shoulder strap 12 and is parallel to the intermediate
line 18
[0063] Note that, in the drawings, X denotes a horizontal line from an anterior axilla point,
and Y denotes a midline.
(1) Largest Attachment Angle θ1 of Shoulder Straps 12
[0064] The largest attachment angle θ1 is defined by an angle of the intermediate line 18
when the medial reference line 27 is in contact with the reference circle 26 in the
cup part 17 at the diagonal position of each shoulder strap 12 and when an intersection
point d2 between the medial reference line 27 and the under-bust line 13 falls within
a range of the side part 22 of the under belt at the diagonal position, the range
including the inferior point 19 of the bust point and the inferior point 20 of the
anterior axilla point on the under-bust line 13.
(2) Smallest Attachment Angle θ2 of Shoulder Straps 12
[0065] The smallest attachment angle θ2 is defined by an angle of the intermediate line
18 when the lateral reference line 28 passes through the inside of the reference circle
26 and when an intersection point e2 between the lateral reference line 28 and the
under-bust line 13 coincides with the inferior point 20 of the anterior axilla point.
[0066] If the attachment angle of the shoulder straps 12 falls outside of the range between
the angles θ1 and θ2, the tensions of the shoulder straps 12 respectively come out
of the reference circles 26 or the side parts 22 of the under belt, so that an effect
of suppressing movement of the breasts is decreased. Further, the armhole lines 24
and the neck line 25 cannot be set to be large.
(3) Position of Maximum Curvature Point 29 of Armhole Line 24
[0067] It is desirable that the position of the maximum curvature point 29 of each armhole
line 24 be located on the inner side of a point X3 in the large skin strain area 30,
on the horizontal line X from the anterior axilla point.
[0068] A specific sports brassiere that is manufactured on the basis of a basic configuration
described with reference to Fig. 9 is illustrated in Fig. 10A and Fig. 10B. This brassiere
includes: the brassiere main body 11 made of a front body 11a for covering a chest
and a back body 11b for covering a back; and the right and left shoulder straps 12
provided between the upper end edges of the front body 11a and the back body 11b.
The under belt 14 is provided at the lower end edge of the brassiere main body 11
with the intermediation of the under-bust line 13. The brassiere material may be in
any form of woven fabric, knitted fabric, non-woven fabric, and the like. Further,
the used fibers may be in any form of filament fibers, spun fibers, and the like,
and it is possible to use, as appropriate: natural fibers such as cotton, linen, and
wool; synthetic fibers such as polyamide fibers, acrylic fibers, and polyolefin fibers;
and spandex fibers and the like that are blended and spun, combined into filaments,
mixed and woven, or mixed and knitted.
[0069] A pair of the right and left bust points 16 is defined in the front body 11a, and
pads are fitted to the rear surface of the brassiere main body 11 with reference to
the positions of the bust points 16. Note that, for some brassieres, such pads are
not fitted, and hence the pads may be used as needed.
[0070] The attachment angle θ of the shoulder straps 12 to the brassiere main body 11n this
case is determined by an inclination angle of the intermediate lines 18 of the shoulder
straps 12. The intermediate lines 18 in the drawings have such an inclination angle
that each intermediate line 18 extends to reach the inferior point 20 of the anterior
axilla point on the under-bust line 13.
[0071] The maximum curvature point 29 of each armhole line 24 is set outside of the large
skin strain area 30, and both the shoulder straps 12 and the brassiere main body 11
are outside of the large skin strain area 30.
Reference Signs List
[0072]
- d1
- medial point
- d2
- intersection point
- e1
- lateral point
- e2
- intersection point
- θ
- attachment angle
- X
- horizontal line from anterior axilla point
- Y
- midline
- 11
- brassiere main body
- 11a
- front body
- 11b
- back body
- 12
- shoulder strap
- 13
- under-bust line
- 14
- under belt
- 16
- bust point
- 17
- cup part
- 18
- intermediate line
- 19
- inferior point of bust point
- 20
- inferior point of anterior axilla point
- 21
- anterior axillary line
- 22
- side part of under belt
- 23
- front part of under belt
- 24
- armhole line
- 25
- neck line
- 26
- reference circle
- 27
- medial reference line
- 28
- lateral reference line
- 29
- maximum curvature point
- 30
- large skin strain area