U.S. patent application number 13/584278 was filed with the patent office on 2013-02-28 for golf club head.
The applicant listed for this patent is Tomoya HIRANO, Yuki MOTOKAWA. Invention is credited to Tomoya HIRANO, Yuki MOTOKAWA.
Application Number | 20130053173 13/584278 |
Document ID | / |
Family ID | 47744514 |
Filed Date | 2013-02-28 |
United States Patent
Application |
20130053173 |
Kind Code |
A1 |
MOTOKAWA; Yuki ; et
al. |
February 28, 2013 |
GOLF CLUB HEAD
Abstract
This head 2 includes a head body h1 as a first member and a face
plate p1 as a second member. A boundary k1 of the first member and
the second member exists on a surface of the head. A deposition
layer is formed in a region including the boundary k1 on the
surface of the head. A temperature Tp in a deposition process is
equal to or less than 150.degree. C. Preferably, the deposition
layer is formed by PVD. Preferably, the first member and the second
member are stuck with an adhesive. Preferably, the deposition layer
has a surface layer and a lower layer. Preferably, the exposed
deposition layer is a TiC layer. Preferably, a total thickness Tt
of the deposition layer is 0.5 .mu.m or greater and 3.0 .mu.m or
less.
Inventors: |
MOTOKAWA; Yuki; (Kobe-shi,
JP) ; HIRANO; Tomoya; (Kobe-shi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
MOTOKAWA; Yuki
HIRANO; Tomoya |
Kobe-shi
Kobe-shi |
|
JP
JP |
|
|
Family ID: |
47744514 |
Appl. No.: |
13/584278 |
Filed: |
August 13, 2012 |
Current U.S.
Class: |
473/349 ;
473/324 |
Current CPC
Class: |
A63B 53/0487 20130101;
A63B 53/04 20130101; A63B 53/042 20200801; A63B 53/0425 20200801;
A63B 53/0408 20200801; A63B 53/0466 20130101; A63B 53/047 20130101;
A63B 60/00 20151001 |
Class at
Publication: |
473/349 ;
473/324 |
International
Class: |
A63B 53/04 20060101
A63B053/04 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 24, 2011 |
JP |
2011-183128 |
Claims
1. A golf club head comprising: a first member; and a second
member, wherein a boundary of the first member and the second
member exists on a surface of the head; a deposition layer is
formed in a region including the boundary on the surface of the
head; and a temperature Tp in a deposition process is equal to or
less than 150.degree. C.
2. The golf club head according to claim 1, wherein the deposition
layer is formed by PVD.
3. The golf club head according to claim 1, wherein the first
member and the second member are stuck with an adhesive.
4. The golf club head according to claim 1, wherein the deposition
layer has a surface layer and a lower layer.
5. The golf club head according to claim 1, wherein the exposed
deposition layer is a TiC layer.
6. The golf club head according to claim 1, wherein a total
thickness Tt of the deposition layer is 0.5 .mu.m or greater and
3.0 .mu.m or less.
7. The golf club head according to claim 5, wherein a thickness of
the TiC layer is 0.3 .mu.m or greater and 2.6 .mu.m or less.
8. The golf club head according to claim 4, wherein a thickness of
the lower layer is 0.1 .mu.m or greater and 0.5 .mu.m or less.
9. The golf club head according to claim 1, wherein the deposition
layer has a surface layer and a second layer; the surface layer is
a TiC layer; and the second layer is a CrN layer.
10. The golf club head according to claim 1, wherein the deposition
layer has a surface layer and a second layer; the surface layer is
a TiC layer; and the second layer is a Zr layer.
11. The golf club head according to claim 1, wherein the deposition
layer has a surface layer and a lower layer; and the lower layer
has higher removability than that of the surface layer, the
removability caused by hydrogen peroxide.
Description
[0001] The present application claims priority on Patent
Application No. 2011-183128 filed in JAPAN on Aug. 24, 2011, the
entire contents of which are hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a golf club head.
[0004] 2. Description of the Related Art
[0005] A golf club head may be subjected to surface processing.
Typical surface processings are painting and plating.
[0006] Japanese Patent Application Laid-Open No. 2001-327636
discloses a golf club head covered with a coating layer formed by
vapor phase coating. The gazette discloses an iron head having a
face plate made of a titanium alloy. Examples of the vapor phase
coating include PVD (physical vapor deposition method), CVD
(chemical vapor deposition method), and a diffusion method.
SUMMARY OF THE INVENTION
[0007] In the head described in the literature, a boundary exists
between the face plate and a head body. It was found that when a
head having a boundary between members is subjected to deposition,
a defect occurs near the boundary.
[0008] It is an object of the present invention to provide a golf
club head capable of suppressing a deposition defect in a boundary
between members.
[0009] A golf club head of the present invention includes a first
member; and a second member. A boundary of the first member and the
second member exists on a surface of the head. A deposition layer
is formed in a region including the boundary on the surface of the
head. A temperature Tp in a deposition process is equal to or less
than 150.degree. C.
[0010] Preferably, the deposition layer is formed by PVD.
[0011] Preferably, the first member and the second member are stuck
with an adhesive.
[0012] Preferably, the deposition layer has a surface layer and a
lower layer.
[0013] Preferably, the exposed deposition layer is a TiC layer.
[0014] Preferably, a total thickness Tt of the deposition layer is
0.5 .mu.m or greater and 3.0 .mu.m or less.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is a perspective view of a golf club head of a first
embodiment of the present invention;
[0016] FIG. 2 is a front view of the head of FIG. 1;
[0017] FIG. 3 is a cross sectional view taken along line F3-F3 of
FIG. 2;
[0018] FIG. 4 is an enlarged cross sectional view in a face
surface;
[0019] FIG. 5 is an enlarged view in a circle F5 of FIG. 2;
[0020] FIG. 6 is an enlarged cross sectional view in a face surface
of a head according to a second embodiment; and
[0021] FIG. 7 is an enlarged cross sectional view in a face surface
of a head according to a third embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0022] Hereinafter, the present invention will be described in
detail based on preferred embodiments with appropriate references
to the accompanying drawings.
[0023] As shown in FIGS. 1 to 3, a head 2 is an iron type golf club
head. The head 2 has a face 4, a hosel 6, and a sole 8. The hosel 6
has a hosel hole 10. A face groove gv is formed in the surface of
the face 4. The description of the face groove gv is omitted in
FIG. 3.
[0024] The central part of the face 4 is subjected to shot blast
processing. All the face grooves gv are located in a region R5
subjected to the shot blast processing. A region Rn which is not
subjected to the shot blast processing exists in each of the toe
side and the heel side of the face 4. A symbol b1 represents a
boundary line of the region R5 and the region Rn.
[0025] The head 2 has a head body h1 as a first member and a face
plate p1 as a second member. The head body h1 (first member) is a
metal. The material of the head body h1 is stainless steel. The
face plate p1 (second member) is a metal. The material of the face
plate p1 is a titanium alloy. The head 2 is a cavity back iron. The
shape of the head 2 is not restricted.
[0026] The head body h1 has a face opening. The contour of the face
opening is substantially equal to that of the face plate p1. The
face plate p1 is fitted into the face opening (see FIG. 3). The
face plate p1 constitutes most of the face 4. All the face grooves
gv are formed in the face plate p1. In FIG. 2, a boundary k1 of the
face plate p1 and the head body h1 is illustrated. The boundary k1
is hardly noticeable in an actual head. Therefore, the description
of the boundary k1 is omitted in FIG. 1.
[0027] In the face 4, the face plate p1 and the head body h1
constitute the same plane PL1. The plane PL1 is a face surface. The
boundary k1 is located on the plane PL1.
[0028] The face 4 is subjected to surface processing. The whole
face 4 is subjected to the surface processing. The surface
processing is deposition. In the embodiment, PVD is employed as the
deposition.
[0029] In the embodiment, the shot blast processing is performed
after deposition processing. The deposition processing may be
performed after the shot blast processing.
[0030] The face groove gv is formed by cutting processing.
Specifically, the face groove gv is processed by a cutter. The
processing is NC processing. NC stands for "Numerical Control".
After the face groove gv is formed, the deposition processing is
performed. Therefore, the surface of the face groove gv (including
the bottom surface of the face groove gv) is also subjected to the
deposition processing.
[0031] As shown in FIG. 2, the heel side end of the face plate p1
is substantially disposed along a boundary line b1. On the other
hand, the toe side end of the face plate p1 is substantially
disposed along the contour of the head 2. The face plate p1 has the
region R5 and the region Rn. The toe side portion of the face plate
p1 is the region Rn. The face plate p1 has the boundary line
b1.
[0032] The surface of the face 4 is a plane. The whole plane
portion is subjected to the deposition. The region subjected to the
deposition includes the boundary k1.
[0033] Examples of the deposition include PVD (physical vapor
deposition method) and CVD (chemical vapor deposition method).
Examples of the PVD include vacuum deposition, sputtering, ion
plating, ion beam deposition, and ion implantation deposition.
Examples of the CVD include plasma CVD, laser excitation CVD, and
light excitation CVD. In respect of a pressure in a chamber in
which a chemical reaction is performed, examples of the CVD include
normal pressure CVD and low-pressure CVD. The deposition can be
executed in known facilities.
[0034] Examples of a substance to be deposited include TiC, TiN,
TiAlN, TiCN, CrN, Zr, ZrN, SiC, Al.sub.2O.sub.3, BN, SiO.sub.2,
TiO.sub.2, ZrO.sub.2, and MgF.sub.2. DLC (diamond like carbon) may
be used. These are known as a substance to be deposited.
[0035] FIG. 4 is a cross sectional view of the vicinity of the
surface of the head 2. A surface layer Ls is formed on the surface
of the face 4. The surface layer Ls is a deposition layer. The
surface layer Ls is formed by the PVD. The surface layer Ls is an
exposed deposition layer.
[0036] In the embodiment, TiC (titanium carbide) is used. That is,
the surface layer Ls is a TiC layer. The TiC exhibits a black
color.
[0037] FIG. 5 is an enlarged view in a circle represented by F5 in
FIG. 2. An appearance defect part fa is represented by a two-dot
chain line in FIG. 5. The appearance defect part fa is observed in
a head to which the present invention is not applied. The
appearance defect part fa forms a color difference capable of being
visually recognized as compared with the surrounding portion. The
appearance defect part fa can be visually recognized. The
appearance defect part fa reduces a product value. When the
appearance defect part fa occurs, the deposition processing needs
to be redone (modified). In the embodiment, the appearance defect
part fa hardly occurs. Even when the appearance defect part fa
occurs, the deposition processing can be modified (redone).
[0038] Many tests are performed in order to eliminate the
appearance defect part fa. As a result, it is found that a
condition in the deposition process can change the rate of
occurrence of the appearance defect part fa. Particularly, it is
found that a temperature Tp in the deposition process contributes
to the suppression of the appearance defect part fa.
[0039] In respect of suppressing the appearance defect part fa, the
temperature Tp is preferably equal to or less than 150.degree. C.,
more preferably equal to or less than 140.degree. C., still more
preferably equal to or less than 130.degree. C., and yet still more
preferably equal to or less than 120.degree. C. When the
temperature Tp is too low, the deposition may become difficult or
the adhesiveness may be reduced. In this respect, the temperature
Tp is preferably equal to or greater than 90.degree. C., and more
preferably equal to or greater than 100.degree. C. When a plurality
of deposition layers is present, the temperature Tp preferably
satisfies these preferred temperature ranges in all the deposition
processes.
[0040] The processing temperature Tp is conventionally a normal
temperature, i.e., about 300.degree. C. in the PVD processing of
the head. An integral-structured head including a face and a body
causes no problem at the processing temperature. However, it is
found that a problem of an appearance defect is caused when a
boundary of a plurality of members exists. The appearance defect
part fa is consequently decreased by lowering the temperature
Tp.
[0041] The details of the occurrence cause of the appearance defect
part fa are unclear. However, the occurrence cause can be guessed
by analyzing results of examples to be described later. One of the
causes capable of being guessed is that a substance (hereinafter,
also referred to as an inhibitor Pt) inhibiting the deposition
exists in the boundary k1. Examples of the inhibitor Pt include an
adhesive, cutting oil, and putty. The adhesive is used to join the
face plate p1 and the head body h1. The cutting oil is used when
the face groove gv is formed by cutting processing. The putty can
be used to prevent the cutting oil from entering the boundary k1.
It is consider that a failure is caused in the deposition because
these inhibitors Pt remain. Particularly, the adhesive is apt to
flow at a high temperature. Therefore, the adhesive may flow out
during high temperature processing.
[0042] The putty is a padding material, and is used to fill up
recesses, cracks and holes or the like. Examples of the putty
include an epoxy putty, a polyester putty, a plaster putty, and a
calcium carbonate putty.
[0043] The adhesive is not restricted. Examples of the adhesive
include an acrylic adhesive, an epoxy adhesive, and an urethane
adhesive. In respect of joining strength, the epoxy adhesive is
preferable. In respect of heat resistance, the urethane adhesive is
preferable. When the temperature Tp in the deposition process is
lowered as described later, the deterioration of the adhesive
caused by heat is suppressed. Therefore, when the temperature Tp is
low, even an adhesive having comparatively low heat resistance can
be used. In this respect, an epoxy adhesive having low heat
resistance and an excellent adhesive force can be preferably used.
When the temperature Tp is low, the degree of freedom of selection
of the adhesive is improved. When the temperature Tp is low, the
adhesive is hardly deteriorated, thereby maintaining the
adhesiveness. Therefore, the face plate p1 is surely fixed.
[0044] In the head 2, the number of the deposition layers is 1. The
number of the deposition layers may be 1, 2, or equal to or greater
than 3. Hereinafter, an example in which the number of the
deposition layers is 2 will be described.
[0045] FIG. 6 is an enlarged cross sectional view of a face 22 in a
head 20 according to a second embodiment. The head 20 is the same
as the head 2 of the first embodiment except that the number of the
deposition layers is 2.
[0046] In the head 20, the number of the deposition layers is
plural. In the head 20, the number of the deposition layers is 2. A
surface layer Ls and a second layer Lg are deposition layers. The
surface layer Ls and the second layer Lg are formed by PVD. The
surface layer Ls is a TiC layer. The second layer Lg is a CrN
(chromium nitride) layer.
[0047] The second layer Lg is an example of a lower layer. The
lower layer is a layer inside the surface layer Ls. The number of
the lower layers may be 1, or, may be equal to or greater than 2.
The lower layer (second layer Lg) is brought into contact with a
material (metal material). The material is the face plate p1 or the
head body h1.
[0048] As described above, the TiC layer exhibits a black color.
Therefore, the face 22 of the head 20 exhibits a black color as in
the head 2. When the TiC layer is removed by abrasion, the CrN
layer is exposed. The CrN layer exhibits a glossy metal color.
[0049] It is found that the CrN layer is effective in maintaining
appearance. When the TiC layer is removed in the case of the head
2, the metal material of the head body h1 or the face plate p1 is
exposed. It is found that the appearance is apt to be reduced when
the metal material is exposed. When the TiC layer is removed by the
use of the head 2 in a bunker or the like, the removing trace looks
like many flaws. The trace looking like the flaws impairs the
appearance. The trace gives a negative impression that the surface
processing is removed to a user. The TiC layer is black, and a
portion in which the black is lost is conspicuous.
[0050] It is found that the removing trace is inconspicious when
the CrN layer exists. The details of the reason are unclear. The
reason to be guessed is that the degree of smoothness of the
surface of an exposed part when the CrN layer exists is increased
as compared with the case where the metal material is exposed. It
is considered that the appearance of the surface is improved when
the degree of smoothness is high, and the removing trace is
inconspicious. When the degree of smoothness is high, a negative
impression that the surface processing is removed hardly
arises.
[0051] FIG. 7 is an enlarged cross sectional view of a face 32 in a
head 30 according to a third embodiment. The head 30 is the same as
the head 2 of the first embodiment except that the number of the
deposition layers is 2.
[0052] In the head 30, the number of the deposition layers is
plural. In the head 30, the number of the deposition layers is 2. A
surface layer Ls and a second layer Lg are deposition layers. The
surface layer Ls and the second layer Lg is formed by PVD. The
surface layer Ls is a TiC layer. A second layer Lg is a Zr
(zirconium) layer.
[0053] As described above, the TiC layer exhibits a black color.
Therefore, the face 32 of the head 30 exhibits a black color as in
the head 2. When the TiC layer is removed by abrasion, the Zr layer
is exposed. The Zr layer exhibits a glossy metal color.
[0054] It is found that the Zr layer is effective in maintaining
appearance. When the TiC layer is removed in the case of the head
2, the metal material of the head body h1 or the face plate p1 is
exposed. It is found that the appearance is apt to be reduced when
the metal material is exposed. When the TiC layer is removed by the
use of the head 2 in a bunker or the like, the removing trace looks
like many flaws. The removing trace impairs the appearance. The
trace gives a negative impression that the surface processing layer
is removed to a user. The TiC layer is black, and a portion in
which the black is lost is conspicuous.
[0055] It is found that the removing trace is inconspicious when
the Zr layer exists. The details of the reason are unclear. The
reason to be guessed is that the degree of smoothness of the
surface of an exposed part when the Zr layer exists is increased as
compared with the case where the metal material is exposed. It is
considered that the appearance of the surface is improved when the
degree of smoothness is high, and the removing trace is
inconspicious.
[0056] As shown in the head 20 and the head 30, it is found that
the existence of a second deposition layer under the surface layer
improves the appearance when the surface layer is removed. The
color of the metal material (stainless steel and a titanium alloy
or the like) resembles that of the second layer. Therefore, it
seems that the appearance when the surface layer is removed is not
changed depending on the existence or non-existence of the second
layer. However, in fact, it is found that the existence of the
second layer improves the appearance during the abrasion of the
surface layer. This was unexpected for those skilled in the
art.
[0057] As shown in examples to be described later, the deposition
process is modified in the head 2, the head 20, and the head 30. As
a result, in the head 2 and the head 20, it is found that a success
rate Sr of the modification of the deposition process is low. On
the other hand, it is found that the success rate Sr is high in the
head 30.
[0058] In the modification of the deposition process, a removing
process is first performed. A remover is used in the removing
process. Preferred examples of the remover include H.sub.2O.sub.2
(hydrogen peroxide). Next, a redeposition process is performed. The
redeposition process is the same as the original deposition
process. As described later, it is estimated to difficult to
completely remove CrN using H.sub.2O.sub.2.
[0059] The reason why the success rate Sr is high in the head 30 is
discussed. When the deposition layer tends to be removed by the
remover, it is considered that the success rate Sr is high. When
the deposition layer is hardly removed by the remover, it is
considered that the success rate Sr is low. When the deposition
layer remains in the removing process, it is guessed that the
remaining deposition layer causes the defect of the
redeposition.
[0060] In respect of improving the success rate Sr, the deposition
layer below the surface layer Ls preferably has higher removability
caused by the remover than that of the surface layer. Examples of
the remover include hydrogen peroxide and sodium hydroxide.
Preferred examples of the remover include the hydrogen peroxide.
Although the sodium hydroxide (NaOH) is also tried, the corrosion
of the face material is caused.
[0061] In respect of durability, the total thickness Tt of the
deposition layer is preferably equal to or greater than 0.5 .mu.m,
and more preferably equal to or greater than 1.0 .mu.m. When the
thickness Tt is excessive, the removal is apt to be caused. In
respect of suppression of the removal and ease of the modification,
the total thickness Tt of the deposition layer is preferably equal
to or less than 3.0 and more preferably equal to or less than 2.5
.mu.m.
[0062] In respect of durability, the thickness of the TiC layer is
preferably equal to or greater than 0.3 .mu.m, and more preferably
equal to or greater than 0.8 .mu.m. In respect of suppression of
the removal and ease of the modification, the thickness of the TiC
layer is preferably equal to or less than 2.6 .mu.m, and more
preferably equal to or less than 2.1 .mu.m.
[0063] In respect of making the removal of the surface layer
inconspicuous, the thickness T2 of the lower layer is preferably
equal to or greater than 0.1 .mu.m, and more preferably equal to or
greater than 0.2 .mu.m. In respect of suppression of the removal
and ease of the modification, the thickness T2 of the lower layer
is preferably equal to or less than 0.5 .mu.m, and more preferably
equal to or less than 0.4 .mu.m. The lower layer means a portion
except the surface layer in the deposition layer.
[0064] A time Tm required for the deposition process can be set so
that the thickness of the deposition layer is suitable.
EXAMPLES
[0065] Hereinafter, the effects of the present invention will be
clarified by examples. However, the present invention should not be
interpreted in a limited way based on the description of the
examples.
[0066] Tests A, B, and C were executed. In the test A, only TiC was
used for a deposition layer. In the test B, TiC (first layer) and
CrN (second layer) were used for the deposition layer. In the test
C, TiC (first layer) and Zr (second layer) were used for the
deposition layer. The results of the test A are shown in following
Tables 1 and 2. The results of the test B are shown in the
following Table 3. The results of the test C are shown in the
following Table 4.
[Test A]
Example 1a
[0067] The same head as the head 2 was produced. A face groove gv
of a face plate p1 was formed by cutting processing (NC
processing). Cutting oil was used during the NC processing. The
face plate p1 was press-fitted into an opening of a head body h1.
Fitting caused by press-fitting was used in combination with an
adhesive to fix the face plate p1. The face plate p1 was joined to
the head body h1 by the adhesive. "EW2010" (trade name)
manufactured by Sumitomo 3M Limited was used as the adhesive. A
face surface was washed before a deposition process. An organic
solvent was used for the washing. Specifically, the washing was a
wiping process. In the wiping process, the face surface was wiped
by a cloth including the organic solvent. The deposition process
was performed after the washing. The kind of the deposition was
PVD. PVD processing was executed under known conditions such as a
vacuum condition. The deposition layer was TiC. In the deposition
process, a processing temperature Tp was 150.degree. C. A time Tm
required for the deposition was 80 minutes. Specifications and
evaluation results of example 1a are shown in the following Table
1.
Examples 2a to 14a
[0068] Heads of examples 2a to 14a were obtained in the same manner
as in the example 1a except for specifications shown in Table 1.
These specifications and evaluation results are shown in the
following Table 1. In the example 8a, water was used in place of
the solvent in the washing. In the example 9a, the adhesive was not
used.
Comparative Examples 1a to 5a
[0069] Heads of comparative examples 1a to 5a were obtained in the
same manner as in the example 1a except for specifications shown in
Table 2. These specifications and evaluation results are shown in
the following Table 2.
TABLE-US-00001 TABLE 1 Specifications and evaluation results of
test A (Examples) Example Example Example Example Example Example
Example 1a 2a 3a 4a 5a 6a 7a Deposition Surface layer TiC TiC TiC
TiC TiC TiC TiC substance Lower layer -- -- -- -- -- -- -- Surface
Temperature Tp 150 140 130 120 110 100 90 layer (.degree. C.) Time
Tm 80 80 80 80 80 80 80 (minute) Thickness T1 1.2 1.2 1.2 1.2 1.2
1.2 1.2 (.mu.m) Lower Temperature Tp -- -- -- -- -- -- -- layer
(.degree. C.) Time Tm -- -- -- -- -- -- -- (minute) Thickness T2 --
-- -- -- -- -- -- (.mu.m) Total thickness Tt of 1.2 1.2 1.2 1.2 1.2
1.2 1.2 deposition layer (.mu.m) Adhesive Use Use Use Use Use Use
Use Washing process Solvent Solvent Solvent Solvent Solvent Solvent
Solvent Appearance defect ratio B B B A A A B Modification
evaluation B B B B B B B Bunker endurance test B B B B B B B
Example Example Example Example Example Example Example 8a 9a 10a
11a 12a 13a 14a Deposition Surface layer TiC TiC TiC TiC TiC TiC
TiC substance Lower layer -- -- -- -- -- -- -- Surface Temperature
Tp 110 110 110 110 110 110 110 layer (.degree. C.) Time Tm 80 80
110 50 200 140 210 (minute) Thickness T1 1.2 1.2 1.9 0.7 3.0 2.6
3.2 (.mu.m) Lower Temperature Tp -- -- -- -- -- -- -- layer
(.degree. C.) Time Tm -- -- -- -- -- -- -- (minute) Thickness T2 --
-- -- -- -- -- -- (.mu.m) Total thickness Tt of 1.2 1.2 1.9 0.7 3.0
2.6 3.2 deposition layer (.mu.m) Adhesive Use Nonuse Use Use Use
Use Use Washing process Water Solvent Solvent Solvent Solvent
Solvent Solvent Appearance defect ratio B A A A A A A Modification
evaluation B B B B B B C Bunker endurance test B B B B B B C
TABLE-US-00002 TABLE 2 Specifications and evaluation results of
test A (Comparative Examples) Comparative Comparative Comparative
Comparative Comparative Example Example Example Example Example 1a
2a 3a 4a 5a Deposition Surface layer TiC TiC TiC TiC TiC substance
Lower layer -- -- -- -- -- Surface Temperature Tp 300 200 170 300
300 layer (.degree. C.) Time Tm 80 80 80 80 80 (minute) Thickness
T1 1.2 1.2 1.2 1.2 1.2 (.mu.m) Lower layer Temperature Tp -- -- --
-- -- (.degree. C.) Time Tm -- -- -- -- -- (minute) Thickness T2 --
-- -- -- -- (.mu.m) Total thickness Tt of 1.2 1.2 1.2 1.2 1.2
deposition layer (.mu.m) Adhesive Use Use Use Nonuse Use Washing
process Solvent Solvent Solvent Water Water Appearance defect ratio
D D D B E Modification evaluation C C C C C Bunker endurance test B
B B B B
[Test B]
Example 1b
[0070] The same head as the head 20 was produced. A head of example
1b was obtained in the same manner as in the example 1a except that
CrN was formed as a lower layer (second layer) and specifications
of each layer were shown in Table 3. Specifications and evaluation
results of the example 1b are shown in the following Table 3.
Examples 2b to 10b and Comparative Examples 1b to 4b
[0071] Heads of examples 2b to 10b and comparative examples 1b to
4b were obtained in the same manner as in the example 1b except for
specifications shown in Table 3. These specifications and
evaluation results are shown in the following Table 3.
TABLE-US-00003 TABLE 3 Specifications and evaluation results of
test B Example Example Example Example Example Example Example
Example 1b 2b 3b 4b 5b 6b 7b 8b Deposition Surface layer TiC TiC
TiC TiC TiC TiC TiC TiC substance Lower layer CrN CrN CrN CrN CrN
CrN CrN CrN Surface Temperature Tp 110 110 110 110 110 110 110 110
layer (.degree. C.) Time Tm 80 80 80 80 80 110 20 150 (minute)
Thickness T1 1.2 1.2 1.2 1.2 1.2 1.9 0.25 2.7 (.mu.m) Lower
Temperature Tp 110 110 110 110 110 110 110 110 layer (.degree. C.)
Time Tm 3 6 15 60 6 6 3 6 (minute) Thickness T2 0.15 0.3 0.4 1.2
0.3 0.3 0.15 0.3 (.mu.m) Total thickness Tt of 1.35 1.5 1.5 1.6 1.5
2.2 0.4 3.0 deposition layer (.mu.m) Adhesive Use Use Use Use Use
Use Use Use Washing process Solvent Solvent Solvent Solvent Water
Solvent Solvent Solvent Appearance defect ratio A A A A C A A A
Modification evaluation C C C C C C C C Bunker endurance test A A A
A A A C A Comparative Comparative Comparative Comparative Example
Example Example Example Example Example 9b 10b 1b 2b 3b 4b
Deposition Surface layer TiC TiC TiC TiC TiC TiC substance Lower
layer CrN CrN CrN CrN CrN CrN Surface Temperature Tp 110 110 300
200 170 110 layer (.degree. C.) Time Tm 160 130 80 80 80 80
(minute) Thickness T1 2.9 2.3 1.2 1.2 1.2 1.2 (.mu.m) Lower
Temperature Tp 110 110 110 110 110 170 layer (.degree. C.) Time Tm
6 6 6 6 6 6 (minute) Thickness T2 0.3 0.3 0.3 0.3 0.3 0.3 (.mu.m)
Total thickness Tt of 3.2 2.6 1.5 1.5 1.5 1.5 deposition layer
(.mu.m) Adhesive Use Use Use Use Use Use Washing process Solvent
Solvent Solvent Solvent Solvent Solvent Appearance defect ratio A A
D D D D Modification evaluation C C C C C C Bunker endurance test C
A A A A A
[Test C]
Example 1c
[0072] The same head as the head 30 was produced. A head of example
1c was obtained in the same manner as in the example 1a except that
Zr was formed as a lower layer (second layer) and specifications of
each layer were shown in Table 4. Specifications and evaluation
results of the example 1c are shown in the following Table 4.
Examples 2c to 9c and Comparative Examples 1c to 4c
[0073] Heads of examples 2c to 9c and comparative examples 1c to 4c
were obtained in the same manner as in the example 1c except for
specifications shown in Table 4. These specifications and
evaluation results are shown in the following Table 4.
TABLE-US-00004 TABLE 4 Specifications and evaluation results of
test C Example Example Example Example Example Example Example 1c
2c 3c 4c 5c 6c 7c Deposition Surface layer TiC TiC TiC TiC TiC TiC
TiC substance Lower layer Zr Zr Zr Zr Zr Zr Zr Surface Temperature
Tp 110 110 110 110 110 110 110 layer (.degree. C.) Time Tm 80 80 80
80 80 110 180 (minute) Thickness T1 1.2 1.2 1.2 1.2 1.2 1.9 2.8
(.mu.m) Lower Temperature Tp 110 110 110 110 110 110 110 layer
(.degree. C.) Time Tm 6 8 10 15 6 6 6 (minute) Thickness T2 0.2 0.3
0.4 0.6 0.2 0.2 0.2 (.mu.m) Total thickness Tt of 1.4 1.5 1.6 1.8
1.4 2.1 3.0 deposition layer (.mu.m) Adhesive Use Use Use Use Use
Use Use Washing process Solvent Solvent Solvent Solvent Water
Solvent Solvent Appearance defect ratio A A A A C A A Modification
evaluation A A A A A A A Bunker endurance test A A A C A A A
Comparative Comparative Comparative Comparative Example Example
Example Example Example 8c Example 9c 1c 2c 3c 4c Deposition
Surface layer TiC TiC TiC TiC TiC TiC substance Lower layer Zr Zr
Zr Zr Zr Zr Surface Temperature Tp 110 110 300 200 170 110 layer
(.degree. C.) Time Tm 190 135 80 80 80 80 (minute) Thickness T1 3.0
2.4 1.2 1.2 1.2 1.2 (.mu.m) Lower Temperature Tp 110 110 110 110
110 170 layer (.degree. C.) Time Tm 6 6 6 6 6 6 (minute) Thickness
T2 0.2 0.2 0.2 0.2 0.2 0.2 (.mu.m) Total thickness Tt of 3.2 2.6
1.4 1.4 1.4 1.4 deposition layer (.mu.m) Adhesive Use Use Use Use
Use Use Washing process Solvent Solvent Solvent Solvent Solvent
Solvent Appearance defect ratio A A D D D D Modification evaluation
C A A A A A Bunker endurance test C A A A A A
[0074] Valuation methods are as follows.
[Appearance Defect Ratio]
[0075] Ten heads were produced for each of the examples and the
comparative examples. An appearance defect part fa near a boundary
k1 was visually confirmed. The head in which the appearance defect
part fa was visually recognized was determined to be defective. The
appearance defect ratio was evaluated at five stages in accordance
with the following standard:
[0076] A: a defect ratio equal to or less than 20%;
[0077] B: a defect ratio greater than 20% and equal to or less than
40%;
[0078] C: a defect ratio greater than 40% and equal to or less than
60%;
[0079] D: a defect ratio greater than 60% and equal to or less than
80%;
[0080] E: a defect ratio greater than 80%.
[Modification Evaluation]
[0081] The deposition process was modified (redone) for all the
heads. A removing process and a redeposition process were executed.
In the removing process, a hydrogen peroxide solution was used as a
remover. Next, the redeposition process was performed in the same
manner as in the original deposition process to which the head was
subjected. Then, an appearance defect was visually confirmed. The
appearance defect was evaluated at three stages in accordance with
the following standard:
[0082] A: a defect ratio equal to or less than 10%;
[0083] B: a defect ratio greater than 10% and equal to or less than
50%;
[0084] C: a defect ratio greater than 50%.
[Bunker Endurance Test]
[0085] A shaft and a grip were attached to each of the heads of
each of the examples and the comparative examples to produce a golf
club. A bunkershot was performed 40 times, and a state of a sole
was quantitatively evaluated by image processing (binarization).
The golf club was evaluated at three stages in accordance with the
following standard:
[0086] A: removal of TiC (black) and flaws of the sole are not so
conspicuous;
[0087] B: removal of TiC (black) and flaws of the sole are slightly
conspicuous; and
[0088] C: removal of TiC (black) and flaws of the sole are
conspicuous.
[0089] The evaluation results of Tables 1 to 4 are analyzed as
follows.
[Test A]
[0090] In the examples 1a to 14a, the appearance defect ratio is
low. This is considered to be because the temperature Tp in the
deposition process is low. In the examples 4a to 6a having a lower
temperature Tp, the appearance defect ratio is lower. These results
suggest that the adhesive acts as an inhibitor Pt.
[0091] In the example 8a, not a solvent but water is used in the
washing process. The appearance defect ratio of the example 8a is
slightly lower than that of the example 5a. For this reason, the
remaining of the inhibitor Pt is estimated to contribute to the
occurrence of the appearance defect part fa.
[0092] In the example 9a, the adhesive is not used, and the
appearance defect ratio is low. In the example 10a, the time Tm
(T1) is lengthened and a thickness Tt is thickened.
[0093] In the examples 1a to 13a, the modification evaluation was
good. It is considered to be because TiC is almost perfectly
eliminated by the remover. Since the thickness Tt was thick in the
example 14a, the modification evaluation was inferior.
[0094] In the comparative examples 1a to 3a and 5a the appearance
defect ratio is deteriorated. This is considered to be because the
temperature Tp is high. This result suggests that the adhesive acts
as the inhibitor Pt.
[0095] The comparative example 4a has a comparatively good
appearance defect ratio. In the comparative example 4a, the
adhesive is not used. This result suggests that the adhesive acts
as the inhibitor Pt.
[0096] In the examples 1a to 13a, the result of the bunker
endurance test is not good. This is considered to be because the
exposure of the metal material (head body h1) reduces the
appearance. Since the thickness Tt was too thick in the example
14a, the bunker endurance test was deteriorated.
[Test B]
[0097] In the examples 1b to 10b (except for the example 5b), the
appearance defect ratio is good. This is considered to be because
the temperature Tp is low. This result suggests that the adhesive
acts as the inhibitor Pt.
[0098] In the example 5b, water is used in the washing process. The
appearance defect ratio of the example 5b is lower than that of the
example 2b. For this reason, the remaining of the inhibitor Pt is
estimated to contribute to the occurrence of the appearance defect
part fa.
[0099] In the examples 1b to 10b, the modification evaluation is
not good. This is considered to be because CrN is not completely
removed by the remover and the redeposition is nonuniformed by the
remaining CrN.
[0100] In the comparative examples 1b to 4b, the appearance defect
ratio is deteriorated. This is considered to be because either
temperature Tp is high. This result suggests that the adhesive acts
as the inhibitor Pt.
[0101] In the examples 1b to 6b, the result of the bunker endurance
test is good. This is considered to be because CrN as a base
improves the appearance.
[0102] In the example 7b, the total thickness Tt of the deposition
layer is thin. Therefore, in the bunker endurance test, TiC and CrN
were removed, and the metal material (head body h1) was
exposed.
[Test C]
[0103] In the examples 1c and 9c (except for the example 5c), the
appearance defect ratio is good. This is considered to be because
the temperature Tp is low. This result suggests that the adhesive
acts as the inhibitor Pt.
[0104] In the example 5c, water is used in the washing process. The
appearance defect ratio of the example 5c is lower than that of the
example 1c. For this reason, the remaining of the inhibitor Pt is
estimated to contribute to the occurrence of the appearance defect
part fa.
[0105] In the examples 1c to 9c (except for the example 8c), the
modification evaluation is good. This is considered to be because
Zr tends to be removed by the remover. Since the thickness Tt was
too thick in the example 8c, the modification evaluation was
deteriorated.
[0106] In the example 4c, the result of the bunker endurance test
is not good. When the thickness T2 of a Zr layer is large, a
difference between hardness of a surface layer Ls (TiC layer) and
hardness of the second layer Lg (Zr layer) is large. A difference
between hardness of a head material and hardness of the second
layer Lg is large. It is considered that distortion is apt to be
caused in the second layer Lg (Zr layer). It is considered that the
crack is apt to be caused based on the hardness difference and the
distortion. In this respect, the thickness of the Zr layer is
preferably equal to or less than 0.4 .mu.m.
[0107] In the comparative examples 1c to 4c, the appearance defect
ratio is deteriorated. This is considered to be because either
temperature Tp is high. This result suggests that the adhesive acts
as the inhibitor Pt. When a plurality of deposition layers is
present, the temperature Tp is preferably low in all the deposition
processes.
[0108] In the examples 1c to 9c (except for the examples 4c and
8c), the result of the bunker endurance test is good. This is
considered to be because Zr as a base improves the appearance.
[0109] Because the total thickness Tt is thick in the examples 14a,
9b, and 8c, the result of the bunker endurance test is not good. It
is considered that the removal is apt to be caused even when the
total thickness Tt is too thick.
[0110] As described above, the examples are highly evaluated as
compared with the comparative examples. From the results, the
advantages of the present invention are apparent.
[0111] The present invention can be applied to all golf club heads
such as a wood type head, a utility type head, a hybrid type head,
an iron type head, and a putter head.
[0112] The description hereinabove is merely for an illustrative
example, and various modifications can be made in the scope not to
depart from the principles of the present invention.
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