U.S. patent number 10,385,182 [Application Number 15/466,183] was granted by the patent office on 2019-08-20 for crash pad for vehicle and manufacturing method thereof.
This patent grant is currently assigned to Hyundai Mobis Co., Ltd.. The grantee listed for this patent is HYUNDAI MOBIS CO., LTD.. Invention is credited to Hyeon Don Kim, Heayeon Lee, Chang Wan Son.
![](/patent/grant/10385182/US10385182-20190820-D00000.png)
![](/patent/grant/10385182/US10385182-20190820-D00001.png)
![](/patent/grant/10385182/US10385182-20190820-D00002.png)
![](/patent/grant/10385182/US10385182-20190820-D00003.png)
![](/patent/grant/10385182/US10385182-20190820-D00004.png)
![](/patent/grant/10385182/US10385182-20190820-D00005.png)
United States Patent |
10,385,182 |
Son , et al. |
August 20, 2019 |
Crash pad for vehicle and manufacturing method thereof
Abstract
The present invention relates to a crash pad for a vehicle and a
manufacturing method thereof. In one embodiment, the method for
manufacturing the crash pad for the vehicle comprises a step of
injecting a skin foam-forming composition between a lower mold
having a color coating layer formed thereon and an upper mold
having a core layer formed thereon, foaming the injected skin
foam-forming composition to form a skin foam layer, wherein the
color coating layer is formed by applying the color coating
composition to the inside surface of the lower mold and curing the
applied color coating composition.
Inventors: |
Son; Chang Wan (Yongin-si,
KR), Kim; Hyeon Don (Yongin-si, KR), Lee;
Heayeon (Seoul, KR) |
Applicant: |
Name |
City |
State |
Country |
Type |
HYUNDAI MOBIS CO., LTD. |
Seoul |
N/A |
KR |
|
|
Assignee: |
Hyundai Mobis Co., Ltd. (Seoul,
KR)
|
Family
ID: |
61912609 |
Appl.
No.: |
15/466,183 |
Filed: |
March 22, 2017 |
Prior Publication Data
|
|
|
|
Document
Identifier |
Publication Date |
|
US 20180118913 A1 |
May 3, 2018 |
|
Foreign Application Priority Data
|
|
|
|
|
Nov 1, 2016 [KR] |
|
|
10-2016-0144659 |
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C08G
18/42 (20130101); C08L 25/06 (20130101); B29C
45/1679 (20130101); C08J 9/365 (20130101); C08J
9/34 (20130101); C08G 18/6511 (20130101); B29C
44/1257 (20130101); C08L 69/00 (20130101); C08J
9/0023 (20130101); C08G 18/69 (20130101); C08J
9/0028 (20130101); C09D 169/00 (20130101); C08G
18/4277 (20130101); B29C 44/02 (20130101); C09D
167/00 (20130101); C08G 18/48 (20130101); C08G
18/6607 (20130101); C08G 18/40 (20130101); C09D
167/00 (20130101); C08L 75/04 (20130101); C08K
5/3492 (20130101); C08K 5/29 (20130101); C09D
169/00 (20130101); C08L 75/04 (20130101); C08K
5/3492 (20130101); C08K 5/29 (20130101); C08G
18/10 (20130101); C08G 18/7664 (20130101); C08G
18/10 (20130101); C08G 18/7671 (20130101); C08G
18/10 (20130101); C08G 18/65 (20130101); C08G
18/10 (20130101); C08G 18/66 (20130101); C08J
2375/04 (20130101); C08J 2203/14 (20130101); B29K
2105/0005 (20130101); B29K 2075/00 (20130101); B29K
2667/00 (20130101); B29K 2625/06 (20130101); B29C
44/5627 (20130101); B29K 2021/003 (20130101); C08G
2101/0008 (20130101); B29K 2995/0097 (20130101); B29K
2669/00 (20130101); B29K 2069/00 (20130101); B29L
2031/3008 (20130101); B29K 2105/16 (20130101); B29K
2025/06 (20130101); C08J 2375/06 (20130101); C08G
2350/00 (20130101); C08J 2375/08 (20130101); C08J
9/141 (20130101); B29K 2995/002 (20130101); B29K
2105/0044 (20130101) |
Current International
Class: |
C08J
9/36 (20060101); C08L 25/06 (20060101); C08L
69/00 (20060101); C09D 167/00 (20060101); C09D
169/00 (20060101); B29C 44/12 (20060101); C08G
18/65 (20060101); C08G 18/66 (20060101); B29C
44/02 (20060101); B29C 45/16 (20060101); C08J
9/00 (20060101); C08G 18/69 (20060101); C08G
18/40 (20060101); C08G 18/42 (20060101); C08G
18/48 (20060101); C08J 9/34 (20060101); C08J
9/14 (20060101); B29C 44/56 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
2004-99798 |
|
Apr 2004 |
|
JP |
|
2011-88054 |
|
May 2011 |
|
JP |
|
20040042677 |
|
May 2004 |
|
KR |
|
10-2013-0142396 |
|
Dec 2013 |
|
KR |
|
10-2015-0104680 |
|
Sep 2015 |
|
KR |
|
10-2015-0135708 |
|
Dec 2015 |
|
KR |
|
Other References
Office Action dated Dec. 19, 2017 in corresponding Korean Patent
Application No. 10-2016-0144659--9 pages. cited by
applicant.
|
Primary Examiner: Yi; Stella K
Attorney, Agent or Firm: Knobbe Martens Olson & Bear
LLP
Claims
What is claimed is:
1. A method of manufacturing a crash pad for a vehicle, the method
comprising: injecting a skin foam-forming composition between a
lower mold having a color coating layer formed thereon and an upper
mold having a core layer formed thereon, and foaming the injected
skin foam-forming composition to form a skin foam layer, wherein
the color coating layer is formed by applying a color coating
composition to an inside surface of the lower mold and curing the
applied color coating composition, wherein the color coating
composition comprises a modified polyester resin, a polycarbonate
diol-based resin and an additive, wherein the additive comprises
one or more of a pigment, a light stabilizer and a
hydrolysis-preventing agent.
2. The method of claim 1, wherein the color coating composition
further comprises a polyester elastomer.
3. The method of claim 1, wherein the color coating composition is
cured at a temperature between about 40.degree. C. and about
70.degree. C. to form the color coating layer.
4. A method of manufacturing a crash pad for a vehicle, the method
comprising: injecting a skin foam-forming composition between a
lower mold having a color coating layer formed thereon and an upper
mold having a core layer formed thereon, and foaming the injected
skin foam-forming composition to form a skin foam layer, wherein
the color coating layer is formed by applying a color coating
composition to an inside surface of the lower mold and curing the
applied color coating composition, wherein the lower mold having
the color coating layer formed thereon is formed by sequentially
applying a release agent and the color coating composition to the
inside surface of the lower mold, and curing the applied color
coating composition.
5. A method of manufacturing a crash pad for a vehicle, the method
comprising: injecting a skin foam-forming composition between a
lower mold having a color coating layer formed thereon and an upper
mold having a core layer formed thereon, and foaming the injected
skin foam-forming composition to form a skin foam layer, wherein
the color coating layer is formed by applying a color coating
composition to an inside surface of the lower mold and curing the
applied color coating composition, wherein the skin foam-forming
composition comprises: a base comprising a polyol compound, a chain
extender and a foaming agent; and an isocyanate-based curing
agent.
6. The method of claim 5, wherein the polyol compound comprises one
or more of diol, triol and a polymeric polyol compound, wherein the
diol comprises one or more of ethylene glycol, diethylene glycol,
butanediol, and hexanediol, wherein the triol comprises one or more
of glycerin, trimethylolpropane, and 1,2,3-hexanetriol, and wherein
the polymeric polyol compound comprises one or more of a polyolefin
polyol compound, a polyester polyol compound, a polycaprolactone
polyol compound, a polyether polyol compound, and a polycarbonate
polyol compound.
7. The method of claim 5, wherein the chain extender comprises one
or more of ethylene glycol, propylene glycol, 1,4-butanediol,
glycerin, diethanolamine, and triethanolamine.
8. The method of claim 5, wherein the base of the skin foam-forming
composition further comprises one or more of a catalyst, a pigment
and a light stabilizer.
9. The method of claim 8, wherein the light stabilizer comprises
one or more of a triazine-based compound, a benzophenone-based
compound and a benzotriazole-based compound.
10. The method of claim 5, wherein the isocyanate-based curing
agent comprises one or more of 4,4'-dicyclohexylmethane
diisocyanate, 4,4-diphenylmethane diisocyanate, bis-4-(isocyanate
chclohexyl)methane, hexamethylene diisocyanate, xylene
diisocyanate, p-phenylene diisocyanate, tolidine diisocyanate,
tetramethylene diisocyanate, dimethyl diisocyanate, trimethyl
hexamethylene diisocyanate, phenylene diisocyanate, and dimethyl
diphenyl diisocyanate.
11. The method of claim 10, wherein the isocyanate-based curing
agent comprises about 40 wt % to about 88 wt % of a monomeric
methylene diphenyl diisocyanate (MDI) having a weight-average
molecular weight of about 200 g/mol to about 300 g/mol, about 10 wt
% to about 58 wt % of a polymeric methylene diphenyl diisocyanate
(MDI) having a weight-average molecular weight of about 350 g/mol
to about 600 g/mol, and about 2 wt % to about 20 wt % of a
methylene diphenyl diisocyanate (MDI) prepolymer.
12. The method of claim 5, wherein the isocyanate-based curing
agent is contained in an amount of about 35 parts by weight to
about 55 parts by weight based on 100 parts by weight of the polyol
compound.
13. The method of claim 1, wherein the core layer is formed to have
a thickness of about 1 mm to about 6 mm, the skin foam layer is
formed to have a thickness of about 3 mm to about 10 mm, and the
color coating layer is formed to have a thickness of about 10 .mu.m
to about 200 .mu.m.
14. The method of claim 1, wherein the core layer comprises: a
matrix resin comprising a polycarbonate-based resin and a
styrene-based resin; and an inorganic filler.
15. The method of claim 1, wherein the skin foam layer and the core
layer are not scored.
16. The method of claim 1, further comprising releasing the crash
pad having the skin foam layer formed therein from the upper and
lower molds, and then scoring the skin foam layer and the core
layer, wherein the scoring is performed using one or more of a
laser, a hot knife, a cold knife, an ultrasonic knife, and
milling.
17. The method of claim 4, wherein the core layer comprises: a
matrix resin comprising a polycarbonate-based resin and a
styrene-based resin; and an inorganic filler.
18. The method of claim 4, wherein the skin foam layer and the core
layer are not scored.
19. The method of claim 4, further comprising releasing the crash
pad having the skin foam layer formed therein from the upper and
lower molds, and then scoring the skin foam layer and the core
layer, wherein the scoring is performed using one or more of a
laser, a hot knife, a cold knife, an ultrasonic knife, and milling.
Description
CROSS-REFERENCE TO RELATED APPLICATION(S)
This application claims the benefit of Korean Patent Application
No. 10-2016-0144659, filed on Nov. 1, 2016 in the Korean
Intellectual Property Office, the entire disclosures of which are
incorporated herein by reference.
BACKGROUND OF THE INVENTION
Field of the Invention
Exemplary embodiments of the present invention relate to a crash
pad for a vehicle and a manufacturing method thereof.
Description of the Related Art
A crash pad, also called "instrument panel", is a vehicle interior
part that is attached to the bottom of the glass in front of the
driver's seat. An airbag is mounted in the crash pad. When a
vehicle accident occurs, the airbag deploys through the seam of the
crash pad to protect the life of the driver and the passenger from
external impact. Thus, the airbag is a part that is very important
in terms of design, convenience and safety.
FIG. 1 shows a conventional crash pad for a vehicle, and FIG. 2
shows the cross-section of a conventional crash pad for a vehicle.
Referring to FIGS. 1 and 2, a crash pad 100 comprises a core layer
1, a foam layer 2 formed on the surface of the core layer 1, and a
skin layer 3 formed on the surface of the foam layer 2. Herein, the
skin layer 3 is formed of a material and a coating material, which
may exhibit the appearance and sensory properties of actual
leather, in order to emphasize design and sensory properties. In
addition, the skin layer 3 may be subjected to a skin scoring
process to form a scoring 4 for deployment of an airbag.
Meanwhile, this crash pad is manufactured by sequentially forming a
skin layer and a core layer, inserting the skin layer and the core
layer into a foaming mold, and foaming polyurethane in the mold to
form a polyurethane foam layer. This crash pad has problems in that
the production thereof is time-consuming and costly. Furthermore,
the skin layer is generally formed to have a thickness of about 1
mm to 2 mm by various processes, and materials or processes used to
the skin layer are costly. For this reason, methods for
manufacturing crash pads having increased competitiveness as a
result of reducing material costs and the number of processes have
been studied.
Prior art documents related to the present invention include Korean
Unexamined Patent Application No. 2015-0135708 (published on Dec.
3, 2015; entitled "Method for manufacturing a skin for a crash
pad").
SUMMARY OF THE INVENTION
One aspect of the present invention is directed to a method for
manufacturing a crash pad for a vehicle. In one embodiment, the
method for manufacturing the crash pad for the vehicle includes a
step of injecting a skin foam-forming composition between a lower
mold having a color coating layer formed thereon and an upper mold
having a core layer formed thereon, and foaming the injected skin
foam-forming composition to form a skin foam layer, wherein the
color coating layer is formed by applying the color coating
composition to the inside surface of the lower mold and curing the
applied color coating composition.
In one embodiment, the color coating composition may include a
modified polyester resin, a polycarbonate diol-based resin and an
additive, wherein the additive may include one or more of a
pigment, a light stabilizer and a hydrolysis-preventing agent.
In another embodiment of the present invention, the color coating
composition may further include a polyester elastomer.
In one embodiment, the color coating composition may be cured at a
temperature between about 40.degree. C. and about 70.degree. C. to
form the color coating layer.
In one embodiment, the lower mold having the color coating layer
formed thereon may be formed by sequentially applying a release
agent and the color coating composition to the inside surface of
the lower mold, and curing the applied color coating
composition.
In one embodiment, the skin foam-forming composition may include: a
base including a polyol compound, a chain extender and a foaming
agent; and an isocyanate-based curing agent.
In one embodiment, the polyol compound may include one or more of
diol, triol and a polymeric polyol compound, in which the diol may
include one or more of ethylene glycol, diethylene glycol,
butanediol, and hexanediol, the triol may include one or more of
glycerin, trimethylolpropane, and 1,2,3-hexanetriol, and the
polymeric polyol compound may include one or more of a polyolefin
polyol compound, a polyester polyol compound, a polycaprolactone
polyol compound, a polyether polyol compound, and a polycarbonate
polyol compound.
In one embodiment, the chain extender may include one or more of
ethylene glycol, propylene glycol, 1,4-butanediol, glycerin,
diethanolamine, and triethanolamine.
In one embodiment, the base may further include one or more of a
catalyst, a pigment and a light stabilizer.
In one embodiment, the light stabilizer may include one or more of
a triazine-based compound, a benzophenone-based compound and a
benzotriazole-based compound.
In one embodiment, the isocyanate-based curing agent may include
one or more of 4,4'-dicyclohexylmethane diisocyanate,
4,4-diphenylmethane diisocyanate, bis-4-(isocyanate
chclohexyl)methane, hexamethylene diisocyanate, xylene
diisocyanate, p-phenylene diisocyanate, tolidine diisocyanate,
tetramethylene diisocyanate, dimethyl diisocyanate, trimethyl
hexamethylene diisocyanate, phenylene diisocyanate, and dimethyl
diphenyl diisocyanate.
In one embodiment, the isocyanate-based curing agent may include
about 40 wt % to about 88 wt % of a monomeric methylene diphenyl
diisocyanate (MDI) having a weight-average molecular weight of
about 200 g/mol to about 300 g/mol, about 10 wt % to about 58 wt %
of a polymeric methylene diphenyl diisocyanate (MDI) having a
weight-average molecular weight of about 350 g/mol to about 600
g/mol, and about 2 wt % to about 20 wt % of a methylene diphenyl
diisocyanate (MDI) prepolymer.
In one embodiment, the isocyanate-based curing agent may be
included in an amount of about 35 parts by weight to about 55 parts
by weight based on 100 parts by weight of the polyol compound.
In one embodiment, the core layer may be formed to have a thickness
of about 1 mm to about 6 mm, the skin foam layer may be formed to
have a thickness of about 3 mm to about 10 mm, and the color
coating layer may be formed to have a thickness of about 10 .mu.m
to about 200 .mu.m.
In one embodiment, the core layer may include: a matrix resin
including a polycarbonate-based resin and a styrene-based resin;
and an inorganic filler.
In one embodiment, the skin foam layer and the core layer may be
formed without scoring.
In one embodiment, the method for manufacturing the crash pad may
further include a step of releasing the crash pad having the skin
foam layer formed therein from the mold, and then scoring the skin
foam layer and the core layer, in which the scoring may be
performed using one or more of a laser, a hot knife, a cold knife,
an ultrasonic knife, and milling.
Another aspect of the present invention is directed to a crash pad
for a vehicle, manufactured by the method for manufacturing the
crash pad for the vehicle. In one embodiment, the crash pad for the
vehicle may include: a core layer; a skin foam layer formed on the
surface of the core layer; and a color coating layer formed on the
surface of the skin foam layer.
In one embodiment, the core layer may have a thickness of about 1
mm to about 6 mm, the skin foam layer may have a thickness of about
3 mm to about 10 mm, and the color coating layer may have a
thickness of about 10 .mu.m to about 200 .mu.m.
In one embodiment, the skin foam layer may be formed without
scoring. In one embodiment, the skin foam layer and the core layer
may be scored layers.
The crash pad for the vehicle according to the present invention is
manufactured without performing conventional skin layer processes,
may have excellent lightweight properties and excellent appearance
and sensory properties such as tactile sensation due to a thin
color coating layer formed therein, and may be highly
cost-effective due to process simplification and reduced production
costs.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a conventional crash pad for a vehicle.
FIG. 2 shows the cross-section of a conventional crash pad for a
vehicle.
FIG. 3 shows a method for manufacturing a crash pad for a vehicle
according to one embodiment of the present invention.
FIG. 4 shows the cross-section of a crash pad for a vehicle
according to one embodiment of the present invention.
FIG. 5 shows photographs in which (a) is a photograph showing the
cross-section of a crash pad for a vehicle, manufactured according
to Example 1 of the present invention, and (b) is a photograph
showing the cross-section of a crash pad for a vehicle,
manufactured according to a Comparative Example for the present
invention.
DESCRIPTION OF SPECIFIC EMBODIMENTS
In the following description, the detailed description of related
known technology will be omitted when it may obscure the subject
matter of the present invention.
In the following description, the detailed description of related
known technology or configuration will be omitted when it may
obscure the subject matter of the present invention. In addition,
the terms of constituent elements, which will be described
hereinafter, are defined in consideration of their functions in the
present invention and may be changed according to the intention of
a user or an operator, or according to the custom. Accordingly,
definitions of these terms must be based on the overall description
herein.
Method for Manufacturing Crash Pad for Vehicle
One aspect of the present invention is directed to a method for
manufacturing a crash pad for a vehicle. FIG. 3 shows a method for
manufacturing a crash pad for a vehicle according to one embodiment
of the present invention.
Referring to FIG. 3, the method for manufacturing the crash pad for
the vehicle comprises a step of injecting a skin foam-forming
composition between a lower mold 301 having a color coating layer
30 formed thereon and an upper mold 302 having a core layer 10
formed thereon, foaming the injected skin foam-forming composition
to form a skin foam layer 20.
Hereinafter, the method for manufacturing the crash pad for the
vehicle according to the present invention will be described in
detail.
Color Coating Layer
Referring to FIG. 3(a), the color coating layer 30 is formed is
formed by applying a color coating composition to the lower mold
301 and curing the applied color coating composition. In one
embodiment, the color coating composition may comprise a modified
polyester resin, a polycarbonate diol-based resin and an additive,
in which the additive may comprise a pigment, a light stabilizer
and a hydrolysis-preventing agent.
Modified Polyester Resin
The modified polyester resin that is used in the present invention
may include a urethane-modified polyester resin. The
urethane-modified polyester resin may be prepared by a conventional
method. In one embodiment, the urethane-modified polyester resin
may be prepared by reacting a polyester prepolymer with an
isocyanate-based curing agent. The urethane-modified polyester
resin may have excellent processability and mechanical
properties.
In one embodiment, the polyester prepolymer may be prepared by
reacting a multifunctional alcohol compound with multifunctional
carboxylic acid.
In one embodiment, the urethane-modified polyester resin may have a
hydroxyl value of about 10 mg KOH/g to about 500 mg KOH/g and a
weight-average molecular weight of about 1,500 g/mol to about
50,000 g/mol. Under such conditions, the urethane-modified
polyester resin may have excellent workability, excellent adhesion
to the color coating layer, and excellent mechanical
properties.
Polycarbonate Diol-Based Resin
The polycarbonate diol-based resin may be contained for the purpose
of improving the mechanical properties, heat resistance and
chemical resistance of the color coating layer by forming a bond
with the modified polyester resin formed in the color coating
layer.
In one embodiment, the polycarbonate diol-based resin may have a
weight-average molecular weight ranging from about 500 g/mol to
3000 g/mol. In this range, the color coating layer may have
excellent mechanical properties, heat resistance and chemical
resistance. For example, the polycarbonate diol-based resin may
have a weight-average molecular weight ranging from about 800 g/mol
to about 2000 g/mol.
In one embodiment, the polycarbonate diol-based resin may be
contained in an amount of about 80 parts by weight to about 250
parts by weight based on 100 parts by weight of the modified
polyester resin. In this content range, the molecular weight of the
color coating layer may be easily increased, and the crash pad
according to the present invention may have excellent mechanical
properties and heat resistance. For example, the polycarbonate
diol-based resin may be contained in an amount of about 80 parts by
weight to about 150 parts by weight. For example, it may be
contained in an amount of about 80, 90, 100, 110, 120, 130, 140,
150, 160, 170, 180, 190, 200, 210, 220, 230, 233, 240 or 250 parts
by weight.
In one embodiment, the modified polyester resin and the polyester
diol-based resin may be contained at a weight ratio ranging from
about 1:0.5 to about 1:1.5. In this weight ratio range, the color
coating composition may have excellent compatibility, and the color
coating layer may have excellent texture and excellent physical
properties such as tensile strength and durability.
Additive
In one embodiment, the additive may comprise a pigment, a light
stabilizer and a hydrolysis-preventing agent.
Pigment
The pigment may be contained for the purpose of realizing the color
of the color coating layer. In one embodiment, the pigment may
comprise one or more of carbon black, titanium dioxide, iron oxide,
and an organic pigment. In one embodiment, the pigment may be
contained in an amount ranging from about 1 part by weight to about
25 parts by weight based on 100 parts by weight of the modified
polyester resin. In this content range, the color of the color
coating layer may be easily realized. For example, the pigment may
be contained in an amount of about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10,
11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24 or 25 parts
by weight.
Light Stabilizer
The light stabilizer may be contained for the purpose of ensuring
the light resistance of the color coating layer to prevent the
color of the crash pad from being changed by sunlight.
In one embodiment, the light stabilizer may comprise one or more of
a triazine-based compound, a benzophenone-based compound and a
benzotriazole-based compound.
In one embodiment, the triazine-based compound may comprise one or
more of 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-(hexyloxy)-phenol and
2-(4,6-bis(2,4-dimethyl-phenyl)-1,3,5-triazin-2-yl-5-octyloxy)phenol.
In one embodiment, the benzotriazole-based compound may comprise
hydroxyphenyl benzotriazole. For example, it may comprise one or
more of 2-(2'-hydroxy-5'-methylphenyl)benzotriazole,
2-(3'-tert-butyl-2'-hydroxy-5'-methyl-phenyl)-5-chlorobenzotriazole,
2-(3',5'-di-tert-butyl-2'-hydroxyphenyl)-5-chlorobenzotriazole,
2-(2'-hydroxy-5'-methylphenyl)-benzotriazole,
2-(2-hydroxy-5-methylphenyl)benzotriazole,
2-(2-hydroxy-5-tert-butyl-phenyl)-5-chlorobenzotriazole,
2-(2-hydroxy-3,5-di-tert-butylphenyl)benzotriazole,
2-(2-hydroxy-5-tert-butylphenyl)benzotriazole, and
2-(2-hydroxy-4-octyloxyphenyl)-benzotriazole.
In one embodiment, the light stabilizer may be contained in an
amount ranging from about 0.5 parts by weight to about 20 parts by
weight based on 100 parts by weight of the modified polyester
resin. In this content range, the color coating layer may have
excellent light resistance while the mechanical strength thereof
may be prevented from decreasing. For example, the light stabilizer
may be contained in an amount of about 0.5, 1, 2, 3, 4, 5, 6, 7, 8,
9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20 parts by
weight.
Hydrolysis-Preventing Agent
The hydrolysis-preventing agent may be contained for the purpose of
preventing side reactions such as hydrolysis of the color coating
layer.
In one embodiment, the hydrolysis-preventing agent may comprise a
carbodiimide-based compound. For example, it may comprise one or
more of a polycarbodiimide compound and a monocarbodiimide
compound.
When the hydrolysis-preventing agent comprises the
carbodiimide-based compound, side reactions such as hydrolysis of
the components of the color coating composition may be prevented so
that the water resistance of the color coating composition may be
improved, and thus the water resistance and durability of the crash
pad in a high-temperature/high-humidity environment may be
improved.
In one embodiment, the polycarbodiimide compound may comprise one
or more of poly(4,4'-diphenylmethane carbodiimide),
poly(4,4'-dicyclohexylmethane carbodiimide),
poly(1,3,5-triisopropylbenzene)polycarbodiimide,
poly(1,3,5-triisopropylbenzene, and
1,5-diisopropylbenzene)polycarbodiimide. In one embodiment, the
monocarbodiimide compound may comprise
N,N'-di-2,6-diisopropylphenyl carbodiimide.
In one embodiment, the hydrolysis-preventing agent may be contained
in an amount ranging from about 0.5 to about 20 parts by weight
based on 100 parts by weight of the modified polyester resin. In
this content range, the color coating layer may have excellent
water resistance and durability while the mechanical strength
thereof will be prevented from decreasing. For example, the
hydrolysis-preventing agent may be contained in an amount of about
0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18,
19 or 20 parts by weight.
Polyester Elastomer
In another embodiment of the present invention, the color coating
composition may further comprise a polyester elastomer. The
polyester elastomer may consist of a hard segment and a soft
segment. The hard segment may have an ester-type main-chain
structure that forms a highly crystalline domain, and the soft
segment serves as a matrix and may be a polymeric polyol consisting
of a polymer of alcohols. Thus, the thermoplastic elastomer resin
composition may have resistance against repeated load, impact
resistance, abrasion resistance, and excellent tensile elongation
and tensile strength.
In one embodiment, the hard segment may be prepared by reacting one
or more of aromatic dicarboxylic acid and aromatic dicarboxylate
with a polyol. In one embodiment, the aromatic dicarboxylic acid
may comprise one or more of terephthalic acid (TPA), isophthalic
acid (IPA), 1,5-naphthalene dicarboxylic acid (1,5-NDCA), and
2,6-naphthalene dicarboxylic acid (2,6-NDCA). In one embodiment,
the aromatic dicarboxylate may comprise dimethyl isophthalate.
In one embodiment, the polyol may comprise one or more of ethylene
glycol, propylene glycol, 1,4-butanediol, 1,5-pentanediol,
1,6-hexanediol, and 1,4-cyclohexanedimethanol.
In one embodiment, the soft segment may comprise a polyalkylene
oxide compound. In one embodiment, the polyalkylene oxide compound
may comprise one or more of polyoxyethylene glyoxypropylene glycol
and polyoxytetramethylene glycol.
When the color coating composition comprises the polyester
elastomer, the color coating layer may have excellent texture and
durability.
In one embodiment, the polyester elastomer may be contained in an
amount ranging from about 80 parts by weight to about 250 parts by
weight based on 100 parts by weight of the modified polyester
resin. In this content range, the color coating layer may have
excellent texture and excellent mechanical properties such as
tensile strength and durability. For example, the polyester
elastomer may be contained in an amount of about 80, 90, 100, 110,
120, 130, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 233,
240 or 250 parts by weight.
In another embodiment, the color coating composition that is used
in the present invention may be a thermosetting polyurethane
coating composition. For example, the color coating composition may
be a two-component thermosetting polyurethane coating composition
comprising: a base comprising a polyol compound, a chain extender
and a pigment; and an isocyanate-based curing agent.
In one embodiment, the color coating layer may be formed by
applying the color coating composition, and then curing the applied
color coating layer at a temperature between 40.degree. C. and
70.degree. C. When curing is performed under this condition, the
color coating layer may be easily cured, and it is possible to
prevent the mold from being contaminated by dye dust occurring in
the color coating layer.
In one embodiment, as shown in FIG. 3, the color coating layer is
formed by applying the color coating composition to the inside
surface of the lower mold 301 and curing the applied color coating
composition.
In one embodiment, the color coating layer may be formed to have a
thickness ranging from about 10 .mu.m to about 200 .mu.m. In this
thickness range, the crash pad may have excellent lightweight
properties and excellent sensory properties such as tactile
sensation while the mechanical properties of the crash pad will not
be deteriorated.
Referring to FIG. 3(a), the color coating layer 30 may be formed by
sequentially applying a release agent 50 and the color coating
composition to the inside surface of the lower mold 301, and then
curing the applied color coating layer.
In one embodiment, the release agent may comprise one or more of
zinc stearate, aluminum stearate, calcium stearate, talc powder,
and silicone oil.
In one embodiment, the surface of the color coating layer may be
embossed or stitched or may have a convex/concave shape. In one
embodiment, in order to form a pattern on the surface of the color
coating layer, the lower mold 301 may be subjected to etching or
nickel electroforming.
Core Layer
A core layer 10 forms the front of the driver's seat and the
passenger's seat and functions to protect the driver and the
passenger from external impact when a clash or rollover accident
occurs. In addition, the core layer 10 may have an insertion hole
through which an airbag module is mounted, a mounting portion to
which an air conditioner is attached, etc.
In one embodiment, the core layer may comprise: a matrix resin
comprising a polycarbonate-based resin and a styrene-based resin;
and an inorganic filler. The styrene-based resin may comprise
acrylonitrile-butadiene-styrene (ABS) resin. In one embodiment, the
matrix resin may comprise PC/ABS resin.
In one embodiment, the inorganic filler may comprise one or more of
talc, whisker, glass fiber, carbon fiber, basalt fiber, and polymer
fiber.
In one embodiment, the above-described core layer-forming
composition may be kneaded, pelletized, and then injection-molded
to form a core layer 10 which is then attached to the upper mold
302 as shown in FIG. 3(b).
In one embodiment, the core layer may have a thickness ranging from
about 1 mm to about 6 mm. In this thickness, the core layer may
have excellent impact resistance and, at the same time, may have an
excellent ability to deploy an airbag when external impact is
applied.
Skin Foam Layer
A skin foam layer 20 serves to ensure physical properties (such as
heat resistance, impact resistance and light resistance) of the
crash pad and to impart excellent sensory properties, for example,
tactile sensation such as cushion feeling, to the driver and the
passenger.
In one embodiment, as shown in FIG. 3(c), the skin foam layer is
formed by attaching the upper mold 302 having the core layer 10
formed thereon to the lower mold 301 having the color coating layer
30 formed thereon, injecting the skin foam forming composition
between the color coating layer 30 and the core layer 10, and
foaming the injected skin foam forming composition.
In another embodiment, the skin foam layer may be formed by
attaching the upper mold having the core layer formed thereon to
the lower mold having the color coating layer formed thereon,
closing the upper mold and the lower mold, injecting the skin foam
forming composition between the color coating layer and the core
layer through an inlet hole, and foaming the injected skin foam
forming composition.
Skin Foam-Forming Composition
The skin foam-forming composition may comprise: a base comprising a
polyol compound, a chain extender and a foaming agent; and an
isocyanate-based curing agent.
Base
The base may comprise a polyol compound, a chain extender and a
foaming agent.
Polyol Compound
In one embodiment, the polyol compound may comprise one or more of
diol, triol, and polymeric polyol.
In one embodiment, the diol may comprise one or more of ethylene
glycol, diethylene glycol, butanediol, and hexanediol.
In one embodiment, the triol may comprise one or more of glycerin,
trimethylolpropane, and 1,2,3-hexanetriol.
In one embodiment, the polymeric polyol may comprise one or more of
polyolefin polyol, polyester polyol, polycaprolactone polyol,
polyether polyol, and polycarbonate polyol. For example, the
polymeric polyol may comprise polyether polyol.
In one embodiment, the polyether polyol compound that is used in
the present invention is prepared by polymerizing one or more
compounds, selected from among ethylene glycol, 1,2-propylene
glycol, 1,3-propylene glycol, butylene glycol, 1,6-hexanediol,
1,8-oxctanediol, neopentyl glycol, 2-methyl-1,3-propanediol,
glycerol, trimethylolpropane, 1,2,3-hexanetriol, 1,2,4-butanetriol,
trimethylolmethane, pentaerythritol, diethylene glycol, triethylene
glycol, polyethylene glycol, tripropylene glycol, polypropylene
glycol, dibutylene glycol, polybutylene glycol, sorbitol, sucrose,
hydroquinone, resorcinol, catechol, and bisphenol, with one or more
of ethylene oxide and propylene oxide.
In one embodiment, polyether polyol may be prepared to comprise a
triol having a hydroxyl (OH) value of about 20 mg KOH/g to about 40
mg KOH/g and a diol having an OH value of about 20 KOH/g to about
40 mg KOH/g.
In one embodiment, the polymeric polymer may be prepared using as a
base a triol having an OH value of about 20 KOH/g to about 40 mg
KOH/g.
In one embodiment, the polyol compound that is used in the present
invention may comprise about 75 wt % to about 90 wt % of triol (OH
value: 20 mg KOH/g to 40 mg KOH/g), more than 0 wt % but not more
than 15 wt % of diol (OH value: 200 mg KOH/g to 500 mg KOH/g), and
more than 0 wt % but not more than 20 wt % of polymeric polyol (OH
value: 20 mg KOH/g to 40 mg KOH/g).
Chain Extender
The chain extender may be contained for the purpose of extending
the chain of polyurethane formed in the skin foam layer or
crosslinking the polyurethane to thereby increase the molecular
weight of the polyurethane and improve mechanical properties, heat
resistance and chemical resistance.
In one embodiment, the chain extender may comprise one or more of
diol, triol and amine compounds. For example, the chain extender
may comprise one or more of ethylene glycol, propylene glycol,
1,4-butanediol, glycerin, diethanolamine (DEOA), and
triethanolamine (TEOA).
In one embodiment, the chain extender may comprise two or more
doils. For example, it may comprise a first diol having an OH value
of about 1500 mg KOH/g to about 2500 mg KOH/g, and a second diol
having an OH value of at least about 500 mg KOH/g but less than
about 1500 mg KOH/g.
In one embodiment, the chain extender may contained in an amount
ranging from 0.1 parts by weight to about 15 parts by weight based
on 100 parts by weight of the polyol compound. In this content
range, the chain extender may easily increase the molecular weight
of the skin foam layer, and the crash pad of the present invention
may have excellent mechanical properties and heat resistance. For
example, the chain extender may contained in an amount of 0.1, 0.5,
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15 parts by
weight.
Foaming Agent
In one embodiment, the foaming agent may comprise one or more of
water, butane, n-pentane, c-pentane, hexane, heptane,
chlorofluorocarbon (CFC 11), hydrogen chlorofluorocarbon (H-CFCs),
hydrogen fluorocarbon (H-FCs), trichlorofluoromethane (Freon 11),
chlorodifluoromethane (R-22), 1,1-dichloro-1-fluoroethane
(HCFC-141b), and 1,1,1,3,3-pentafluoropropane (HFC-245fa).
In one embodiment, the foaming agent may be contained in an amount
ranging from about 0.1 parts to about 15 parts by weight based on
100 parts by weight of the polyol compound. In this content range,
the foaming agent may easily foam the skin foam forming composition
while the mechanical properties of the skin foam layer will be
prevented from decreasing. For example, the foaming agent may be
contained in an amount of about 0.1, 0.5, 1, 2, 3, 4, 5, 6, 7, 8,
9, 10, 11, 12, 13, 14, or 15 parts by weight. In another
embodiment, the foaming may comprise, based on 100 parts by weight
of the polyol compound, about 0.1-3 parts by weight of water and
about 2 parts by weight to about 10 parts by weight of
n-pentane.
In one embodiment of the present invention, the base of the skin
foam forming composition may further comprise one or more of a
catalyst, a pigment and a light stabilizer.
Catalyst
The catalyst may be contained for the purpose of promoting the
reaction between the polyol compound and isocyanate during
formation of the skin foam layer and controlling a resin forming
reaction and a foaming reaction in the foaming process. In one
embodiment, the catalyst may further comprise an amine-based
compound. For example, it may comprise one or more of
triethylenediamine, pentamethyl dipropylenetriamine, and
bis(2-dimethylaminoethyl)ether.
In one embodiment, the catalyst may be contained in an amount
ranging from about 0.01 parts by weight to about 3 parts by weight
based on 100 parts by weight of the polyol compound. In this
content range, the skin foam layer may be formed with uniform
density, and uniform pores may be formed. For example, the catalyst
may be contained in an amount of about 0.01, 0.05, 0.1, 0.5, 1, 2
or 3 parts by weight.
Pigment
The pigment may be contained for the purpose of realizing the color
of the skin foam layer. In one embodiment, the pigment may comprise
one or more of carbon black, titanium dioxide, iron oxide, and an
organic pigment. For example, it may comprise carbon black. In one
embodiment, the pigment may be contained in an amount ranging from
about 1 part by weight to about 8 parts by weight based on 100
parts by weight of the polyol compound. In this content range, the
color of the skin foam layer may be easily realized. For example,
the pigment may be contained in an amount of about 1, 2, 3, 4, 5,
6, 7 or 8 parts by weight.
Light Stabilizer
The light stabilizer may be contained for the purpose of ensuring
the light resistance of the crash pad to prevent the color of the
crash pad from being changed by sunlight.
In one embodiment, the light stabilizer may comprise one or more of
triazine-, benzophenone- and benzotriazole-based compounds.
In one embodiment, the triazine-based compound may comprise one or
more of 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-(hexyloxy)-phenol and
2-(4,6-bis(2,4-dimethyl-phenyl)-1,3,5-triazin-2-yl-5-octyloxy)phenol.
In one embodiment, the benzotriazole-based compound may comprise
hydroxyphenyl benzotriazole. For example, it may comprise one or
more of 2-(2'-hydroxy-5'-methylphenyl)benzotriazole,
2-(3'-tert-butyl-2'-hydroxy-5'-methyl-phenyl)-5-chlorobenzotriazole,
2-(3',5'-di-tert-butyl-2'-hydroxyphenyl)-5-chlorobenzotriazole,
2-(2'-hydroxy-5'-methylphenyl)-benzotriazole,
2-(2-hydroxy-5-methylphenyl)benzotriazole,
2-(2-hydroxy-5-tert-butyl-phenyl)-5-chlorobenzotriazole,
2-(2-hydroxy-3,5-di-tert-butylphenyl)benzotriazole,
2-(2-hydroxy-5-tert-butylphenyl)benzotriazole, and
2-(2-hydroxy-4-octyloxyphenyl)-benzotriazole.
In one embodiment, the light stabilizer may be contained in an
amount ranging from about 0.5 parts by weight to about 6 parts by
weight based on 100 parts by weight of the polyol compound. In this
content range, the skin foam layer may have excellent light
resistance while the mechanical strength of the skin foam layer may
be prevented from decreasing. For example, the light stabilizer may
be contained in an amount of about 0.5, 1, 2, 3, 4, 5 or 6 parts by
weight.
Isocyanate-Based Curing Agent
The isocyanate-based curing agent is contained for the purpose of
forming the skin foam layer by its reaction with the base.
In one embodiment, the isocyanate-based curing agent may comprise
one or more of 4,4'-dicyclohexylmethane diisocyanate,
4,4-diphenylmethane diisocyanate, bis-4-(isocyanate
chclohexyl)methane, hexamethylene diisocyanate, xylene
diisocyanate, p-phenylene diisocyanate, tolidine diisocyanate,
tetramethylene diisocyanate, dimethyl diisocyanate, trimethyl
hexamethylene diisocyanate, phenylene diisocyanate, and dimethyl
diphenyl diisocyanate.
For example, the isocyanate-based curing agent may comprise
methylene diphenyl diisocyanate (MDI) having an isocyanate (NCO)
content of about 26% to about 30%.
In one embodiment, the isocyanate-based curing agent may comprise
about 40 wt % to about 88 wt % of monomeric methylene diphenyl
diisocyanate (MDI) having a weight-average molecular weight of
about 200 g/mol to about 300 g/mol, about 10 wt % to about 58 wt %
of polymeric methylene diphenyl diisocyanate (MDI) having a
weight-average molecular weight of about 350 g/mol to about 600
g/mol, and about 2 wt % to about 20 wt % of a methylene diphenyl
diisocyanate (MDI) prepolymer.
In one embodiment, the methylene diphenyl diisocyanate (MDI)
prepolymer may be prepared by reacting a polyol compound with an
excessive amount of monomeric methylene diphenyl diisocyanate.
In this content range, the skin foam layer may have excellent
tactile sensation and mechanical properties.
In one embodiment, the isocyanate-based curing agent may have a
viscosity of about 50 cPs to about 250 cPs (at 25.degree. C.) and a
specific gravity of about 1.21 to about 1.23. Under such
conditions, the isocyanate-based curing agent may have excellent
workability and reactivity.
In one embodiment, the isocyanate-based curing agent may be
contained in an amount ranging from about 35 parts by weight to
about 55 parts by weight based on 100 parts by weight of the polyol
compound. In this content range, the skin foam layer may have
excellent tactile sensation, heat resistance and mechanical
properties. For example, the isocyanate-based curing agent may be
contained in an amount of about 35, 36, 37, 38, 39, 40, 41, 42, 43,
44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54 or 55 parts by
weight.
In one embodiment, the skin foam layer may be formed to have a
thickness ranging from about 3 mm to about 10 mm. In this thickness
range, the mechanical properties and heat resistance of the skin
foam layer may be ensured.
In one embodiment, the skin foam layer may be formed to have a
hardness ranging from about 80 to about 90 (shore A) as measured in
accordance with ASTM D 2240 standards. In this hardness range, the
tactile sensation, heat resistance and mechanical properties of the
skin foam layer will all be excellent. For example, the skin foam
layer may be formed to have a hardness of about 80, 81, 82, 83, 84,
85, 86, 87, 88, 89 or 90 (shore A).
In the present invention, the skin foam layer may be formed without
scoring. The crash pad of the present invention allows the airbag
module to be easily deployed from the crash pad, even when the
crash pad is not subjected to a scoring process. Furthermore, the
airbag module may easily deploy from the crash pad when external
impact is applied. In addition, processes for producing the crash
pad may be simplified, and the production cost may be reduced.
Thus, the crash pad according to the present invention may be
produced with high productivity and highly cost-effective.
Scoring Process
In another embodiment of the present invention, the method may
further comprise a step of releasing the crash pad 20 having the
skin foam layer formed therein from the mold, and then scoring the
skin foam layer and the core layer. When the scoring is formed, the
scoring may be broken when external impact is applied, so that the
airbag module may easily deploy from the crash pad.
In one embodiment, the scoring may be performed using one or more
of a laser, a hot knife, a cold knife, an ultrasonic knife, and
milling.
Crash Pad for Vehicle
Another aspect of the present invention is directed to a crash pad
for a vehicle, manufactured by the above-described method for
manufacturing the crash pad for the vehicle. FIG. 4 shows the
structure of a crash pad for a vehicle according to one embodiment
of the present invention. Referring to FIG. 4, a crash pad 200 for
a vehicle comprises: a core layer 10; a skin foam layer 20 formed
on the surface of the core layer 10; and a color coating layer 30
formed on the surface of the skin foam layer 20. The core layer,
the skin foam layer and the color coating layer may be formed using
the same components and contents as described above, and thus the
detailed description thereof is omitted.
In one embodiment, the core layer 10 may be formed to have a
thickness of about 1 mm to about 6 mm, the skin foam layer 20 may
be formed to have a thickness of about 3 mm to about 10 mm, and the
color coating layer 30 may be formed to have a thickness of about
10 .mu.m to about 200 .mu.m.
In one embodiment, the skin foam layer 20 may be formed to have a
hardness of about 30 to about 80 (shore C) as measured in
accordance with ASTM D 2240 standards. In this thickness range, the
tactile sensation, heat resistance and mechanical properties of the
skin foam layer may all be excellent.
In one embodiment, the skin foam layer and the core layer may be
formed without scoring. The crash pad according to the present
invention may be manufactured to have a thin thickness, and thus
has excellent lightweight properties. In addition, it may have an
excellent ability to deploy an airbag, even when a process of
scoring the skin foam layer and the core layer is not
performed.
In another embodiment, the skin foam layer and the core layer may
be subjected to a scoring process.
Hereinafter, preferred examples of the present invention will be
described in further detail. However, these examples are for
illustrative purposes only and are not intended to limit the scope
of the present invention in any way.
EXAMPLE 1
(1) Color coating composition
Components used in the color coating composition are as
follows.
(A) As a modified polyester resin, a urethane-modified polyester
resin having a weight-average molecular weight of 3,000 g/mol to
10,000 g/mol was used.
(B) Polycarbonate diol-based resin
(B1) A polycarbonate diol-based resin having a weight-average
molecular weight of 2,000 g/mol was used. (B2) A polycarbonate
diol-based resin having a weight-average molecular weight of 800
g/mol was used.
(C) A polyester elastomer was used.
(D) Additive
(D1) As a light stabilizer, a triazine-based compound was used.
(D2) As a hydrolysis-preventing agent, a polycarbodiimide-based
compound was used.
Using the components and contents shown in Table 1, a color coating
composition was prepared.
(2) Skin foam-forming composition: a skin foam-forming composition
was prepared comprising: a base comprising 100 parts by weight of a
polyol compound (comprising 85 wt % of triol (OH value: 35 mg
KOH/g), 10 wt % of diol (OH value: 300 mg KOH/g) and 5 wt % or less
of a polymeric polyol (OH value: 30 mg KOH/g)), 5 parts by weight
of a chain extender (comprising a first diol having an OH value of
2000 mg KOH/g and a second diol comprising an OH value of 800 mg
KOH/g), 5 parts by weight of a light stabilizer (hydroxyphenyl
benzotriazole), and a foaming agent (comprising 0.5 parts by weight
of water and 5 parts by weight of n-pentane); and 40 parts by
weight of an isocyanate-based curing agent (comprising 60 wt % of a
monomeric methylene diphenyl diisocyanate having a weight average
molecular weight of 250 g/mol, 30 wt % of a polymeric methylene
diisocyanate having a weight-average molecular weight of 450 g/mol,
and 10 wt % of a methylene diphenyl diisocyanate prepolymer).
(3) Core layer: a core layer was prepared comprising: a matrix
resin comprising a polycarbonate-based resin and a styrene-based
resin; and an inorganic filler.
A release agent was applied to a lower mold, and then a color
coating composition was applied (forming density: 400 kg/m.sup.3)
and cured at 50.degree. C., thereby forming a color coating layer
having a thickness of 40 .mu.m.
Next, an upper mold having a 5 mm thick core layer formed thereon
was placed on the lower mold, and the skin foam forming composition
was injected between the color coating layer and the core layer and
foamed to form a skin foam layer having a thickness of 5 mm. Then,
the resulting crash pad for a vehicle was released from the
mold.
EXAMPLES 2 to 7
Crash pads for vehicles were manufactured in the same manner as
described in Example 1, except that the components and contents
shown in Table 1 below were used to prepare color coating
compositions.
TABLE-US-00001 TABLE 1 Components Examples (unit: parts by weight)
1 2 3 4 5 6 7 (A) 100 100 100 100 100 100 100 (B) (B1) -- -- -- 100
-- -- -- (B2) -- -- -- -- 120 -- -- (C) 100 233 233 -- -- 100 100
(D) (D1) 15 15 25 15 15 30 15 (D2) -- -- -- -- -- -- 5
COMPARATIVE EXAMPLE
A crash pad was manufactured in the same manner as described in the
Example, except that a 0.5 mm thick skin layer comprising an
olefinic resin was formed instead of the color coating layer and
that the core layer was scored to a depth of 0.3 mm by use of a hot
knife.
TEST EXAMPLE
(1) Measurement of tensile strength, elongation and tearing
strength: for the crash pads manufactured in Examples 1 to 7,
tensile strength (kgf/cm.sup.2), elongation (%) at breakage and
tearing strength (kgf/cm) were evaluated. The results of the
evaluation are shown in Table 2 below.
TABLE-US-00002 TABLE 2 Examples (color coating layer (forming
density: 400 kg/m.sup.3)) 1 2 3 4 5 6 7 Tensile strength 8.8 8.6
8.9 8.4 8.2 8.3 8.2 (kgf/cm.sup.2) Elongation (%) 108 113 121 103
105 105 105 Tearing strength 4.3 4.3 4.5 4.2 4.1 4.1 4.2
(kgf/cm)
(2) Airbag deployment test: In accordance with Hyundai Motor
Company ES84500-13 (passenger airbag invisible door performance
specification), a passenger airbag (PAB) module was placed in a
crash pad manufactured in each of Examples 1 to 4 and the
Comparative Example, and the inflator detonator was exploded by
applying an electrical signal thereto at room temperature
(21.degree. C.), low temperature (-35.degree. C.) and high
temperature (85.degree. C.). Whether or not the air bag was
deployed through a seam line formed in the crash pad and whether or
not crash pad pieces scattered during airbag deployment was
examined, and the results were recorded as "Pass" or "Fail" in
Table 3 below.
TABLE-US-00003 TABLE 3 Examples 1 2 3 4 5 6 7 Airbag Pass Pass Pass
Pass Pass Pass Pass deployment test
FIG. 5(a) is a photograph showing the cross-section of a crash pad
for a vehicle, manufactured according to Example 1 of the present
invention, and FIG. 5(b) is a photograph showing the cross-section
of a crash pad for a vehicle, manufactured according to a
Comparative Example for the present invention. From the results in
Tables 2 and 3 above and FIG. 5, it could be seen that the crash
pads of the Examples, which comprise the color coating layer, had
physical properties comparable to those of the crash pad of the
Comparative Example, could be manufactured by simplified processes
at reduced costs such as material costs, and had a small thickness,
indicating that the lightweight properties of the crash pad could
be achieved. In addition, it could be seen that, because the
thickness of the crash pad of the Example of the present invention
was reduced, the crash pad of the Example has an excellent ability
to deploy an airbag, even when the scoring process as described in
the Comparative Example was not performed.
The embodiments of the present invention have been disclosed above
for illustrative purposes. Those skilled in the art will appreciate
that various modifications, additions and substitutions are
possible, without departing from the scope and spirit of the
invention as disclosed in the accompanying claims.
* * * * *