U.S. patent application number 16/323992 was filed with the patent office on 2019-06-13 for resin composition, filament and resin powder for three-dimensional printer, and shaped object and production process therefor.
This patent application is currently assigned to OTSUKA CHEMICAL CO., LTD.. The applicant listed for this patent is OTSUKA CHEMICAL CO., LTD.. Invention is credited to Kousuke Inada, Masagoro Okada, Akira Takarada.
Application Number | 20190177510 16/323992 |
Document ID | / |
Family ID | 61300756 |
Filed Date | 2019-06-13 |
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United States Patent
Application |
20190177510 |
Kind Code |
A1 |
Inada; Kousuke ; et
al. |
June 13, 2019 |
RESIN COMPOSITION, FILAMENT AND RESIN POWDER FOR THREE-DIMENSIONAL
PRINTER, AND SHAPED OBJECT AND PRODUCTION PROCESS THEREFOR
Abstract
Provided is a resin composition, a filament and resin powder for
a three-dimensional printer, a shaped object, and a production
method for the shaped object, all of which make it easy to produce
a shaped object and can improve, in shaping using a
three-dimensional printer, the resistance to delamination of the
shaped object and the resistance to warpage and shrinkage of the
shaped object. A resin composition contains: inorganic fibers
having an average fiber length of 1 .mu.m to 300 .mu.m and an
average aspect ratio of 3 to 200; and a thermoplastic resin and
serves as a shaping material for a three-dimensional printer.
Inventors: |
Inada; Kousuke; (Tokyo,
JP) ; Okada; Masagoro; (Tokushima-shi, JP) ;
Takarada; Akira; (Tokushima-shi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
OTSUKA CHEMICAL CO., LTD. |
Osaka-shi, Osaka |
|
JP |
|
|
Assignee: |
OTSUKA CHEMICAL CO., LTD.
Osaka-shi, Osaka
JP
|
Family ID: |
61300756 |
Appl. No.: |
16/323992 |
Filed: |
August 23, 2017 |
PCT Filed: |
August 23, 2017 |
PCT NO: |
PCT/JP2017/030040 |
371 Date: |
February 7, 2019 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C08K 9/06 20130101; C08K
3/22 20130101; B33Y 70/00 20141201; C08L 101/00 20130101; C08K 3/24
20130101; C08K 3/40 20130101; C09D 11/102 20130101; C09D 11/38
20130101; C08K 7/10 20130101; C08K 2201/004 20130101; B29C 64/153
20170801; C08K 2003/2237 20130101; C08L 77/00 20130101; B33Y 10/00
20141201; C08K 3/34 20130101; B29C 64/118 20170801; C08K 7/04
20130101; C08K 7/10 20130101; C08L 77/02 20130101; C08K 7/10
20130101; C08L 77/06 20130101 |
International
Class: |
C08K 7/10 20060101
C08K007/10; C08L 101/00 20060101 C08L101/00; B29C 64/118 20060101
B29C064/118; B29C 64/153 20060101 B29C064/153 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 30, 2016 |
JP |
2016-167914 |
Apr 3, 2017 |
JP |
2017-073789 |
Claims
1. A resin composition containing; inorganic fibers having an
average fiber length of 1 .mu.m to 300 .mu.m and an average aspect
ratio of 3 to 200; and a thermoplastic resin, the resin composition
serving as a shaping material for a three-dimensional printer.
2. The resin composition according to claim wherein the inorganic
fibers have a Mohs hardness of 5 or less.
3. The resin composition according to claim 1, wherein the
inorganic fibers are at least one selected from the group
consisting of potassium titanate and wollastonite.
4. The resin composition according to claim 1, wherein a content of
the inorganic fibers is 1% by mass to 40% by mass in a total amount
of 100% by mass of the resin composition.
5. The resin composition according to claim 1, wherein the
three-dimensional printer is based on a fused deposition modeling
process or a powder bed fusion process.
6. A filament for a fused deposition modeling-based
three-dimensional printer, the filament being made of the resin
composition according to claim 1.
7. A resin powder for a powder bed fusion-based three-dimensional
printer, the resin powder being made of the resin composition
according to claim 1.
8. A shaped object shaped from the resin composition according to
claim 1 with a three-dimensional printer.
9. A shaped object shaped from the filament according to claim 6
with a fused deposition modeling-based three-dimensional
printer.
10. A shaped object shaped from the resin powder according to claim
7 with a powder bed fusion-based three-dimensional printer.
11. A method for producing a shaped object, wherein a shaped object
is produced with a three-dimensional printer using the resin
composition according to claim 1.
12. A method for producing a shaped object, wherein the filament
according to claim 6 is fed to a fused deposition modeling-based
three-dimensional printer.
13. A method for producing a shaped object, wherein the resin
powder according to claim 7 is fed to a powder bed fusion-based
three-dimensional printer.
Description
TECHNICAL FIELD
[0001] The present invention relates to resin compositions as
shaping materials for three-dimensional printers, filaments and
resin powders for three-dimensional printers, and shaped objects
and production methods for the shaped objects.
BACKGROUND ART
[0002] A three-dimensional (3D) printer is technology for
calculating the shapes of thin cross-sections from
three-dimensional data input by a CAD or, the like and depositing
layer upon layer of a material based on the calculation results to
shape a 3D object and is also referred to as additive manufacturing
technology. The three-dimensional printer requires no mold assembly
that should be used in injection molding, enables the shaping of
complicated 3D structures that could not be molded by injection
molding, and has therefore received attention as a high-mix
low-volume manufacturing technology.
[0003] As materials for the three-dimensional printer (also
referred as additive manufacturing materials), various materials
have been developed according to the process or usage of the
three-dimensional printer. The major materials used include light
curable resins, thermoplastic resins, metals, ceramics, and
wax.
[0004] The three-dimensional printer technology is classified based
on how to three-dimensionally shape an object from a material, into
(1) binder jetting process, (2) directed energy deposition process,
(3) material extrusion process, (4) material letting process, (5)
powder bed fusion process, (6) sheet lamination process, (7) vat
photopolymerization process, and others. Three-dimensional printers
adopting, among the above processes, the material extrusion process
(also referred to as the fused deposition modeling process) are
decreasing in price and therefore increasing in demand as those for
home use and office use. Furthermore, in relation to
three-dimensional printers adopting the powder bed fusion process,
the development of a system achieving improvements in recyclability
of powder materials has advanced. Therefore, the powder bed fusion
process is a process attracting much attention.
[0005] The fused deposition modeling process is a process for
shaping an object by fluidizing a thermoplastic resin having the
shape of a thread called a filament or other shapes with a heating
device inside an extrusion head, then discharging the fluid resin
through a nozzle onto a platform, and cooling the resin into a
solid state while gradually depositing layer upon layer of it
according to the cross-sectional shapes of a desired object to be
shaped. However, if the shaping is made using a thermoplastic resin
not blended with any additive (so-called neat resin), there arise
problems including delamination of a shaped object and warpage of
the shaped object. Furthermore, if a thermoplastic resin blended
with a fibrous filler, such as glass fibers or carbon fibers, is
used, there arises a problem of difficulty of shaping due to
clogging of the extrusion head, wear of the extrusion head, and so
on.
[0006] Meanwhile, Patent Literature 1 discloses that with the use
of a thermoplastic resin blended with a nanofiller, such as carbon
nanotubes, for a fused deposition modeling-based three-dimensional
printer, a shaped object can be obtained which has a desired
function that could not be achieved by a thermoplastic resin
only.
[0007] The powder bed fusion process is a process for shaping an
object by forming a thin layer of resin powder, melting it with an
energy source, such as laser or electronic beam, according to the
cross-sectional shape of a desired object to be shaped, solidifying
it, depositing a new thin layer of resin powder on top of the
solid, likewise melting it with the energy source, such as laser or
electronic beam, according to the cross-sectional shape of the
desired object to be shaped, solidifying it, and repeating these
steps.
CITATION LIST
Patent Literature
[0008] Patent Literature 1: JP-A-2016-28887
SUMMARY OF INVENTION
Technical Problem
[0009] However, it is known that uniform dispersion of a nanofiller
in a thermoplastic resin as in Patent Literature 1 is not easy and
that the melting viscosity of an obtained thermoplastic resin
composition increases. Furthermore, Patent Literature 1 discloses
no specific method for improving the resistance to delamination of
a shaped object and the resistance to warpage and shrinkage of the
shaped object. Also in the powder bed fusion process, since resin
is deposited layer by layer, there arise problems of, like the
fused deposition modeling process, delamination of a shaped object
and warpage and shrinkage of the shaped object.
[0010] An object of the present invention is to provide a resin
composition, a filament and resin powder for a three-dimensional
printer, a shaped object, and a production method for the shaped
object, all of which make it easy to produce a shaped object and
can improve, in shaping using a three-dimension printer, the
resistance to delamination of the shaped object and the resistance
to warpage and shrinkage of the shaped object.
Solution to Problem
[0011] The present invention provides a resin composition, a
filament and resin powder for a three-dimensional printer, a shaped
object, and a method for producing the shaped object which are
described below.
[0012] Aspect 1: A resin composition containing: inorganic fibers
having an average fiber length of 1 .mu.m to 300 .mu.m and an
average aspect ratio of 3 to 200; and a thermoplastic resin, the
resin composition serving as a shaping material for a
three-dimensional printer.
[0013] Aspect 2: The resin composition according to aspect 1,
wherein the inorganic fibers have a Mohs hardness of 5 or less.
[0014] Aspect 3: The resin composition according to aspect 1 or 2,
wherein the inorganic fibers are at least one selected from the
group consisting of potassium titanate and wollastonite.
[0015] Aspect 4: The resin composition according to any one of
aspects 1 to 3, wherein a content of the inorganic fibers is 1% by
mass to 40% by mass in a total amount of 100% by mass of the resin
composition.
[0016] Aspect 5: The resin composition according to any one of
aspects 1 to 4, wherein the three-dimensional printer is based on a
fused deposition modeling process or a powder bed fusion
process.
[0017] Aspect 6: A filament for a fused deposition modeling-based
three-dimensional printer, the filament being made of the resin
composition according to any one of aspects 1 to 4.
[0018] Aspect 7: A resin powder for a powder bed fusion-based
three-dimensional printer, the resin powder being made of the resin
composition according to any one of aspects 1 to 4.
[0019] Aspect 8: A shaped object shaped from the resin composition
according to any one of aspects 1 to 4 with a three-dimensional
printer.
[0020] Aspect 9: A shaped object shaped from the filament according
to aspect 6 with a fused deposition modeling-based
three-dimensional printer.
[0021] Aspect 9: A shaped t shaped from the filament according to
aspect 6 with a fused deposition modeling-based three-dimensional
printer.
[0022] Aspect 10: A shaped object shaped from the resin powder
according to aspect 7 with a powder bed fusion-based
three-dimensional printer.
[0023] Aspect 11: A method for producing a shaped object, wherein a
shaped object is produced with a three-dimensional printer using
the resin composition according to any one of aspects 1 to 4.
[0024] Aspect 12: A method for producing a shaped object, wherein
the filament according to aspect 6 is fed to a fused deposition
modeling-based three-dimensional printer.
[0025] Aspect 13: A method for producing a shaped object, wherein
the resin powder according to aspect 7 is fed to a powder bed
fusion-based three-dimensional printer.
Advantageous Effects of Invention
[0026] The present invention makes it easy to produce a shaped
object and can improve, in shaping using a three-dimensional
printer, the resistance to delamination of the shaped object and
the resistance to warpage and shrinkage of the shaped object.
BRIEF DESCRIPTION OF DRAWINGS
[0027] FIG. 1 is a photograph showing a shaped object produced
using a resin composition according to Comparative Example 1.
[0028] FIG. 2 is a photograph showing a shaped object produced
using a resin composition according to Example 2.
[0029] FIG. 3 is a side view showing the shape of a tensile
specimen.
[0030] FIG. 4 is a cross-sectional view showing the shape of a
bending specimen.
[0031] FIG. 5 is a schematic side view for illustrating the amount
of warpage of flat-plate shaped objects made in Test Examples 1 to
11 and Comparative Test Examples 1 to 8.
[0032] FIG. 6 is a schematic side view for illustrating the amount
of warpage of shaped objects of bending specimens made in Test
Example 34 and Comparative Test Examples 23 to 24.
DESCRIPTION OF EMBODIMENTS
[0033] Hereinafter, a description will be given of example of a
preferred embodiment for working of the present invention. However,
the following embodiment is simply illustrative. The present
invention is not at all limited by the following embodiment.
<Resin Composition>
[0034] A resin composition according to the present invention
contains: inorganic fibers (A) having an average fiber length of 1
.mu.m to 300 .mu.m and an average aspect ratio and a thermoplastic
resin (B) and may further contain other additives (C) as
necessary.
(Inorganic Fibers (A))
[0035] The inorganic fibers for se in the present invention are
powder formed of fibrous particles, and have an average fiber
length of 1 .mu.m to 300 .mu.m and an average aspect ratio of 3 to
200. The average fiber length is preferably 1 .mu.m to 200 .mu.m,
more preferably 3 .mu.m to 100 .mu.m, and still more preferably 5
.mu.m to 50 .mu.m. The average aspect ratio is preferably 3 to 100,
more preferably 5 to 50, and still more preferably 8 to 40. The use
of the inorganic fibers having the above average fiber length and
average aspect ratio makes it easy to produce a shaped object and
can improve, in shaping using a three-dimensional printer, the
resistance to delamination of the shaped object and the resistance
to warpage and shrinkage of the shaped object.
[0036] The inorganic fibers for use in the present invention has,
from the viewpoint of wear of an extrusion head, a Mohs hardness of
preferably 5 or less, more preferably 1 to 5, and still more
preferably 2 to 5. Examples of the type of the inorganic fibers
include potassium titanate, wollastonite, aluminum borate,
magnesium borate, xonotlite, zinc oxide, and basic magnesium
sulfate. Preferred among the above various types of inorganic
fibers is, from the viewpoint of mechanical properties, at least
one selected from the group consisting of potassium titanate and
wollastonite. The Mohs hardness is an index indicating the hardness
of a substance, wherein when two different minerals are rubbed
against each other, scratched one of them is a substance having a
lower hardness.
[0037] Heretofore known potassium titanates can be widely used and
examples include potassium tetratitanate, potassium hexatitanate,
and potassium octatitanate. There is no particular limitation as to
the dimensions of potassium titanate so long as they are within the
above-described dimensions of the inorganic fibers. However,
normally, its average fiber diameter is 0.01 .mu.m to 1 .mu.m,
preferably 0.05 .mu.m to 0.8 .mu.m, and more preferably 0.1 .mu.m
to 0.7 .mu.m, its average fiber length is 1 .mu.m to 50 .mu.m,
preferably 3 .mu.m to 30 .mu.m, and more preferably 10 .mu.m to 20
.mu.m, and its average aspect ratio is 10 or more, preferably 10 to
100, and more preferably 15 to 35. In the present invention, even
marketed products can be used and examples that can be used include
"TISMO D" (average fiber length: 15 .mu.m, average fiber diameter:
0.5 .mu.m) and "TISMO N" (average fiber length: 15 .mu.m, average
fiber diameter: 0.5 .mu.m) both manufactured by Otsuka Chemical
Co., Ltd.
[0038] Wollastonite is inorganic fibers made of calcium
metasilicate. There is no particular limitation as to the
dimensions of wollastonite so long as they are within the
above-described dimensions of the inorganic fibers. However,
normally, its average fiber diameter is 0.1 .mu.m to 15 .mu.m,
preferably 1 .mu.m to 10 .mu.m, and more preferably 2 .mu.m to 7
.mu.m, its average fiber length is 3 .mu.m to 180 .mu.m, preferably
10 .mu.m to 100 .mu.m, and more preferably 20 .mu.m to 40 .mu.m,
and its average aspect ratio is 3 or more, preferably 3 to 30, and
more preferably 5 to 15. In the present invention, even marketed
products can be used and an example that can be used is "Bistal W"
(average fiber length: 25 .mu.m, average fiber diameter: 3 .mu.m)
manufactured by Otsuka Chemical Co., Ltd.
[0039] The above average fiber length and average fiber diameter
can be measured by observation with a scanning electron microscope,
and the average aspect ratio (average fiber length/average fiber
diameter) can be calculated from the average fiber length and the
average fiber diameter. For example, a plurality of inorganic
fibers are shot with a scanning electron microscope, images of 300
inorganic fibers are arbitrarily selected from the observed images,
and their fiber lengths and fiber diameters are measured. The
average fiber length can be determined by adding all the fiber
diameters and dividing the sum by the number of fibers, while the
average fiber diameter can be determined by adding all the fiber
diameters and dividing the sum by the number of fibers.
[0040] Fibrous particles as used in the present invention means
particles having an L/B of 3 or more and an L/T of 3 or more where
a length L represents the dimension of the longest side of, among
cuboids (circumscribing cuboids) circumscribing the particle, a
cuboid having the minimum volume, a breadth B represents the
dimension of the second longest side of the cuboid and a thickness
T represents the dimension of the shortest side of the cuboid. The
length L and the breadth B correspond to the fiber length and the
fiber diameter, respectively. Platy particles herein refer to
particles having an L/B of below 3 and an L/T of 3 or more.
[0041] Regarding the inorganic fibers in order to increase the
wettability with the thermoplastic resin and further improve
physical properties, such as mechanical strength, of the obtained
resin composition, treated layers made of a surface treatment agent
may be formed on the surfaces of inorganic fibers for use in the
present invention. Examples of the surface treatment agent include
silane coupling agents and titanium coupling agents. Preferred
among them are silane coupling agents and more preferred are
aminosilane coupling agents, epoxysilane coupling agents,
vinylsilane coupling agents, and alkylsilane coupling agents. These
agents may be used alone or as a mixture of two or more.
[0042] Examples of the aminosilane coupling agents include
N-2-(aminoethyl)-3-aminopropylmethydimethoxysilane,
N-2-(aminoethyl)-3-aminopropyltrimethoxysilane,
3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane,
3-ethoxysilyl-N-(1,3-dimethylbutylidene)propylamine,
N-phenyl-3-aminopropyltrimethoxysilane, and
N-(vinylbenzyl)-2-aminoethyl-3-aminoproyrltrimethoxysilane.
[0043] Examples of the epoxysilane coupling agents include
3-glycidyloxypropyl(dimethoxy)methylsilane,
3-glycidyloxpropyltrimethoxysilane diethoxy(3-(glycidyloxypropyl)
methylsilane, triethoxy(3-glycidyloxypropyl)silane, and
2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane.
[0044] Examples of the vinylsilane coupling agents include
vinyltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane,
3-methacryloxypropyltrimethoxysilane,
3-methacryloxypropylmethyldiethoxysilane, and
3-methacryloxypropyltriethoxysilane.
[0045] Examples of the alkylsilane coupling agents include
methyltrimethoxysilane, dimethyldimethoxysilane,
trimethylmethoxysilane, methyltriethoxysilane,
ethyltrimethoxysilane, n-propylmethoxysilane,
isobutyltrimethoxysilane, isobutyltriethoxysilane,
n-hexyltrimethoysilane, n-hexyltriethoxysilane,
cyclphexylmethyldimethoxysilane, n-octyltriethoxysilane,
n-decyltrimethoxysilane
[0046] Known surface treatment methods can be used as the method
for forming treated layers made of a surface treatment agent on the
surfaces of the inorganic fibers and examples include: a wet method
of dissolving the surface treatment agent solvent prompting
hydrolysis (for example, water, an alcohol or a solvent of them) to
prepare a solution and spraying the solution on the inorganic
fibers; and an integral blend method of blending the inorganic
fibers and the surface treatment agent with the resin
composition.
[0047] No particular limitation is placed on the amount of surface
treatment agent in treating the surfaces of the inorganic fibers
according to the present invention with the surface treatment
agent, but, in the case of the wet method, the solution of the
surface treatment agent may be sprayed so that the amount of
surface treatment agent reaches 0.1 parts by mass to 5 parts by
mass and preferably 0.3 parts by mass to 2 parts by mass relative
to 100 parts by mass inorganic fibers. On the other hand, in the
case of the integral blend method, the treatment agent may be
blended with the resin composition so that the amount of surface
treatment agent reaches 0.1 parts by mass to 20 parts mass relative
to 1 parts by mass of inorganic fibers. If the amount of surface
treatment agent is within the above ranges, the adhesion of the
inorganic fibers to the thermoplastic resin can increase to improve
the dispersibility of the inorganic fibers.
(Thermoplastic Resin (B))
[0048] No particular limitation is placed on the type of the
thermoplastic resin for use in the resin composition according to
the present invention so long as it can be used three-dimensional
printers, but examples that can be cited include: polyolefin
resins, such as polypropylene (PP) resin, polyethylene (PE) resin,
cyclic polyolefin (CO,) resin, and cyclic olefin copolymer (COC)
resin; styrene resins, such as polystyrene (PS) resin, syndiotactic
polystyrene (SPS) resin, and acrylonitrile-butylene-styrene
copolymer (ABS) resin; polyester resins, such as polylactic (PLA)
resin, polyethylene terephthalate (PET) resin, and polybutylene
terephthalate (PBT) resin; polyacetal (POM) resin; polycarbonate
(PC) resin; aliphatic polyamide (PA) resins, such as polyamide 6
resin, polyamide 66 resin, polyamide 11 resin, polyamide 12 resin,
polyamide 46 resin, polyamide 6 resin-polyamide 66 resin copolymer
(polyamide 6/66 resin) and polyamide 6 resin-polyamide 12 resin
copolymer (polyamide 6/12 regin); semi-aromatic polyamide (PA)
resins composed of a structural unit with an aromatic ring and
structural unit free from aromatic ring, such as polyamide MXD6
resin, polyamide 6T resin, polyamide 9T resin, and polyamide 10T
resin; polyphenylene sulfide (PPS) resin; polyether sulfone (PES)
resin; liquid crystal polyester (LCP) resin; aromatic polyether
ketone resins, such as polyether ketone (PEK) resin, polyether
ether ketone (PEEK) resin, polyether ketone ketone (PEKK) resin,
and polyether ether ketone ketone (PEEKK) resin; polyether imide
(PEI) resin; polyamide-imide (PAI) resin; and thermoplastic
polyimide (TPI) resin.
[0049] Preferred in the fused deposition modeling-based
three-dimensional printer and the powder bed fusion-based
three-dimensional printer is at least one selected from the group
consisting of polyolefin resin, styrene resin, polyester resin,
polyacetal (POM) resin, polycarbonate (PC) resin, aliphatic
polyamide (PA) resin, semi-aromatic polyamide (PA) resin,
polyphenylene sulfide (PPS) resin, polyether imide (PEI) resin, and
polyether ether ketone (PEEK) resin.
[0050] Mixtures of at least two compatible thermoplastic resins
selected from among the above thermoplastic resins, i.e., polymer
alloys, or the like can also be used.
(Other Additives (C))
[0051] The resin composition according to the present invention may
contain other additives without any loss of its preferred physical
properties. Examples of the other additives include inorganic
fillers other than the above-mentioned inorganic fibers, a
stabilizer, a nucleating agent, an antistat, an antioxidant, a
weatherproofer, a metal deactivator, a ultraviolet ray absorber, a
germ- and mildew-proofing agent, a deodorant, a conductive
additive, a dispersant, a softener (plasticizer), a colorant, a
flame retardant, a sound deadener, a neutralizer, an antiblocking
agent, a flow modifier, a mold release agent, a lubricant, and an
impact resistance improver.
[0052] The resin composition may contain at least one of these
additives.
(Method for Producing Resin Composition)
[0053] The resin composition according to the present invention can
be produced mixing and heating (particularly, melt kneading) the
above components, the inorganic fibers (A), the thermoplastic resin
(B), and, as necessary, the other additives (C).
[0054] For melt kneading, any known melt kneader, for example, a
biaxial extruder, can be used. Specifically, the resin composition
can be produced by: (1) a method of preliminarily mixing the
components with a mixer (a tumbler, a Henschel mixer or the like),
melt kneading the mixture with a melt kneader, and then pelletizing
it with a pelletization device (such as a pelletizer); (2) a method
of adjusting a master batch of desired components, mixing it with
other components as necessary, and melt kneading the mixture into
pellets with a melt kneader; (3) a method of feeding the components
into a melt kneader to form pellets; or other methods.
[0055] No particular limitation is placed on the processing
temperature during melt kneading so long as it is within a
temperature range in which the thermoplastic resin (B) can melt.
Normally, the cylinder temperature of a melt kneader for use in the
melt kneading is controlled within this range.
[0056] The content of the inorganic fibers (A) in the resin
composition according to the present invention is, in a total
amount of 100% by mass of the resin composition, preferably 1% by
mass to 40% by mass, more preferably 3% by mass to 30% by mass, and
still more preferably 7% by mass to 25% by mass.
[0057] The content of the thermoplastic resin (B) in the resin
composition according to the present invention is, in a total
amount of 100% by mass of the resin composition, preferably 50% by
mass to 99% by mass, more preferably 60% by mass to 97% by mass,
and still more preferably 65% by mass to 93% by mass.
[0058] No particular limitation is placed on the content of other
additives (C) which are additives except for the above-described
essential components and allowed to be used the present invention,
without any loss of the preferred physical properties of the resin
composition. The content of the other additives is normally 10% by
mass or less and preferably 5% by mass or less in a total amount of
100% by mass of the resin composition.
[0059] By controlling the components of the resin composition
according to the present invention within the above ranges, the
resistance to delamination of a shaped object and the resistance to
warpage and shrinkage of the shaped object in shaping using a
three-dimensional printer can be improved.
[0060] In this manner, the resin composition according to the
present invention exerting desired effects is produced.
<Shaping Material for Three-Dimensional Printer>
[0061] The resin composition according to the present invention a
shaping material for a three-dimensional printer. The shaping
material for a three-dimensional printer in the present invention
refers to a material for use in applying it to a three-dimensional
printer (also referred to as an additive manufacturing apparatus)
to obtain a three-dimensional shaped object and is composed of the
resin composition.
[0062] The shaping material for a three-dimensional printer
according to the present invention can be used in any method so
long as the method is to shape object by melting the shaping
material by heat based on a design on a computer. For example, the
shaping material can be suitably used in the fused deposition
modeling process or the powder bed fusion process.
[0063] The fused deposition modeling process is a process for
shaping a desired shaped object by fluidizing a thermoplastic resin
having the shape of pellets, the shape of a thread called a
filament or other shapes with a heating device inside an extrusion
head, then discharging the fluid resin through a nozzle onto a
platform, and cooling the resin into a solid state while gradually
depositing layer upon layer of it. The use of the resin composition
according to the present invention as a shaping material enables
shaping using a fused deposition modeling-based three-dimensional
printer without clogging of the extrusion head or wear of the
extrusion head that might occur with the use of a resin composition
blended with a fibrous filler, such as glass fibers or carbon
fibers. For example, even through a thin nozzle having a head
diameter of 0.5 mm or less, shaping can be achieved without the
occurrence of the clogging of the extrusion head or wear of the
extrusion head. In addition, it can be assumed that, although the
reason is not clear, the inorganic fibers (A) can not only improve
the resistance to warpage and shrinkage of the shared object but
also increase the interfacial strength between the layered resin
portions, thus preventing delamination of the shaped object.
[0064] No particular limitation is placed on the method for
producing filament and an example is a method including: an
extrusion step of extruding the resin composition according to the
present invention produced by the above-described method as molten
strand through a die hole in a molder and guiding the molten strand
into a cooling water bath to obtain a strand; a stretching step of
hot stretching the strand to obtain a filament; and the step of
rolling up the filament.
[0065] No particular limitation is placed on the shape of the
filament. Examples that can be cited as the cross-sectional shape
thereof include circular, rectangular, flattened, ellipsoidal,
cocoon-like, trefoil, and like non-circular shapes. Circular is
preferred from the viewpoint of ease of handling. No limitation is
placed on the length of the filament and it can be set at any value
according to industrial production conditions or without
interfering with the use for a fused deposition modeling-based
three-dimensional printer. No particular limitation is also placed
on the diameter of the filament and, for example, it is 0.5 mm to 3
mm and particularly 1 mm to 2 mm. Note that the diameter of the
filament refers to the maximum of diameters measured on
cross-sections of the filament perpendicular to the direction of
length of the filament.
[0066] The filament may be a composite filament in which the resin
composition according to the present invention is combined with
another or other resin components. Examples of the cross-sectional
structure of the composite filament that can be cited include a
radially oriented structure, a side-by-side structure, a sea-island
structure, and a core-in-sheath structure.
[0067] The powder bed fusion process is a process for shaping an
object by depositing resin powder layer by layer, melting each
layer into a particular cross-sectional shape, with an energy
source, such as laser or electronic beam, and solidifying it. Since
the resin composition according to the present invention is used as
a shaping material, be assumed that, although the reason is not
clear, the inorganic fibers (A) cannot only improve the resistance
to warpage and shrinkage of the shaped object but also increase the
interfacial strength between the layer resin portions, thus
preventing delamination of the shaped object.
[0068] No particular limitation is placed on the method producing
resin powder and examples include: a method of producing resin
powder by crushing the resin composition with a crusher or other
means, then grinding the crushed product with a jet mill or other
means, and then classifying the ground product (mechanical grinding
method); a method of producing resin powder by dissolving the resin
composition in a solvent and then cooling the solution
(precipitation method; and a method of producing resin powder by
melt mixing a resin A and a resin B incompatible with the in A and
immersing the obtained molten mixture in a solvent poor for the
resin A and good for the resin B, thus decomposing the molten
mixture (melt-mixing method). No limitation is placed on the
particle diameter of the resin powder and it can be set at any
value according to industrial production conditions or without
interfering with the use for a three-dimensional printer, but the
average particle diameter is preferably 10 .mu.m to 150 .mu.m and
more preferably 30 .mu.m to 80 .mu.m.
[0069] The average particle diameter can be measured by the laser
diffraction and scattering method and is a particle diameter at
cumulative integrated value of 50% in a particle size distribution
measured by the laser diffraction and scattering method (a
volume-based 50% cumulative particle diameter), i.e., D.sub.50 (a
median diameter). This volume-based 50% cumulative particle
diameter (D.sub.50) is a particle diameter at a cumulative value of
50% in a cumulative curve of a particle size distribution
determined on a volume basis, the cumulative curve assuming the
total volume of particles as 100%, where during accumulation the
number of particles is counted from a smaller size side.
[0070] Examples of the shape of particles forming the powder
include spherical and amorphous (amoeboid, boomerang-like, cross,
konpeito-like, potato-like, and so on), but spherical is preferred
from the viewpoint of interface strength. The shapes of particles
can be observed by scanning electron microscopy.
<Shaped Object and Production Method Therefor>
[0071] A shaped object according to the present invention is an
object shaped from the resin composition according to the present
invention with a three-dimensional printer. In using the resin
composition according to the present invention in the form of a
filament, a shaped object can be produced, for example, by
performing shaping by feeding the filament into a fused deposition
modeling-based three-dimensional printer. In using the resin
composition according to the present invention in the form of
powder, a shaped object can be produced, for example, by performing
shaping by feeding the powder into a powder bed fusion-based
three-dimensional printer.
[0072] In a method for producing a shaped object according to the
present invention, shaped object is produced by a three-dimensional
printer using the resin composition according to the present
invention.
[0073] In using the resin composition according to the present
invention in the form of a filament, a shaped object can be
produced, for example, feeding the filament into a fused deposition
modeling-based three-dimensional printer. Specifically, a shaped
object can be produced feeding the filament into a fused deposition
modeling-based three-dimensional printer, fluidizing the filament
with a heating device inside an extrusion head, then discharging
the fluid through a nozzle onto a platform, and cooling it into a
solid state while gradually depositing layer upon layer of it
according to the cross-sectional shape of a desired object to be
shaped.
[0074] In using the resin composition according to the present
invention in the form of powder, a shaped object can be produced,
for example, by feeding the powder into a powder bed fusion-based
three-dimensional printer. Specifically, a shaped object can be
produced by feeding the resin powder into powder bed fusion-based
three-dimensional printer, forming on a vertically or electronic
beam, according to the cross-sectional shape of a desired object to
be shaped, solidifying it, depositing a new thin layer of the resin
powder on top of the solid, likewise melting it with the energy
source, such as laser or electronic beam, according to the
cross-sectional shape of the desired object to be shaped,
solidifying it, and repeating these steps.
EXAMPLES
[0075] Hereinafter, a specific description will be given of the
present invention with reference to Examples and Comparative
Examples, but the present invention is not limited to these
examples. Details of raw materials used in Examples and Comparative
Examples are as described below. The average fiber diameter and the
average aspect ratio were measured using a field-emission scanning
electron microscope (SEM, S-4800 manufactured by Hitachi
High-Technologies Corporation), the shapes of particles were
confirmed by the SEM, the average particle diameter was measured
using, with the exception of carbon black, a laser diffraction
particle size distribution measurement device (SALD-2100
manufactured by Shimadzu Corporation), and the average particle
diameter of carbon black was measured using the SEM.
(Inorganic Fibers))
[0076] Potassium titanate (trade name: TISMO D102, manufactured
Otsuka Chemical Co., Ltd., average fiber length: 15 .mu.m, average
fiber diameter: 0.5 .mu.m, average aspect ratio: 30); and
[0077] Wollastonite (trade name: Bistal W, manufactured by Otsuka
Chemical Co., Ltd., average fiber length: 25 .mu.m, average fiber
diameter: 3 .mu.m, average aspect ratio: 8)
(Thermoplastic Resin)
[0078] Polyamide 12 resin (PA12 resin);
[0079] Polyamide MXD6 resin (PAMXD6 resin)
[0080] Acrylonitrile-butylene-styrene copolymer resin (ABS
resin);
[0081] Cyclic olefin copolymer resin (COC resin);
[0082] Polybutylene terephthalate resin (PBT resin); and
[0083] Polyphenylene sulfide resin PPS resin)
(Other Additives)
[0084] Carbon black (trade name: #3050, manufactured by Mitsubishi
Chemical Corporation, average particle diameter: 50 nm,
amorphous-shaped particles);
[0085] Talc (average particle diameter: 8 .mu.m, platy particles);
and
[0086] Glass beads (trade name: EGB 063Z manufactured by
Potters-Ballotini Co., Ltd., average particle diameter: 25 .mu.m
spherical particles)
<Production of Resin Composition and Filament>
(Examples 1 to 11 and Comparative Examples 1 to 8)
[0087] Materials were melt-kneaded in each composition ratio shown
in Tables 1 and 2 using a biaxial extruder to produce pellets The
cylinder temperature of the biaxial extruder was 190.degree. C. to
230.degree. C. in Examples 1 to 4 and Comparative Examples 1 to 4,
230.degree. C. to 270.degree. C. in Examples 5 and 6 and
Comparative Example 5, 200.degree. C. to 230.degree. C. in Examples
7 and 8 and Comparative Example 6, 210.degree. C. to 240.degree. C.
in Example 9 and Comparative Example 7, and 200.degree. C. to
250.degree. C. in Examples 10 and 11 and Comparative Example 8.
[0088] The obtained pellets were loaded into a filament extruder,
thus obtaining a filament with a filament diameter of 1.7 mm.
TABLE-US-00001 TABLE 1 Comp. Comp. Comp. Comp. Ex. 1 Ex. 2 Ex. 3
Ex. 4 Ex. 1 Ex. 2 Ex. 3 Ex. 4 Inorganic fibers potassium titanate %
by mass 5 10 20 wollastonite % by mass 10 Thermoplastic resin PA12
resin % by mass 95 90 80 90 100 99 95 90 Other additives carbon
black % by mass 1 5 talc % by mass 10
TABLE-US-00002 TABLE 2 Comp. Comp. Comp. Comp. Ex. 5 Ex. 6 Ex. 5
Ex. 7 Ex. 8 Ex. 6 Ex. 9 Ex. 7 Ex. 10 Ex. 11 Ex. 8 Inorganic fibers
potassium titanate % by mass 10 20 10 20 10 10 20 Thermoplastic
resin PAMXDS resin % by mass 90 80 100 ABS resin % by mass 90 80
100 COC resin % by mass 90 100 PBT resin % by mass 90 80 100
<Production of Three-Dimensional Shaped Object Based on Fused
Deposition Modeling Process>
(Test Examples 1 to 11 and Comparative Test Examples 1 to 8)
[0089] The filament obtained in each of Examples 1 to 11 and
Comparative Examples 1 to 8 was deposited into layers in a
thickness direction by fused deposition modeling-based
three-dimensional printer (manufactured by MUTOH INDUSTRIES, LTD.,
trade name: MF1100) under the associated printing conditions shown
in Tables 3 and 4, thus producing a flat-plate shaped object 100 mm
long, 2 mm wide, and 50 mm thick.
[0090] FIG. 1 shows a photograph of a shaped object (Comparative
Test Example 1) produced using the resin composition according to
Comparative Example 1, and FIG. 2 shows a photograph of a shaped
object (Test Example 2) produced using the resin composition
according to Example 2.
(Test Examples 12 to 22 and Comparative Test Examples 9 to 16)
[0091] The filament obtained in each of Examples 1 to 11 and
Comparative Examples 1 to 8 was produced into a dumbbell tensile
specimen having a shape shown in FIG. 3 by a fused deposition
modeling-based three-dimensional printer (manufactured by MUTOH
INDUSTRIES, LTD., trade name: MF 1100) under the associated
printing conditions shown in Tables 5 and 6.
(Test Examples 23 to 33 and Comparative Test Examples 17 to 22)
[0092] The filament obtained in each of Examples 1 to 11,
Comparative Example 1, and Comparative Examples 4 to 8 was produced
into a bending specimen having a shape shown in FIG. 4 by a fused
deposition modeling-based three-dimensional printer (manufactured
by MUTOH INDUSTRIES, LTD., trade name: MF1100) under the associated
printing conditions shown in Tables 7 and 8.
<Evaluation>
(1) Amount of Warpage
[0093] The flat-plate shaped objects produced under the conditions
in Tables 3 and 4 were measured in terms of amount of warpage with
a caliper. The amount of warpage W is, as shown in FIG. 5, a
difference in height along a build-up direction during shaping
between the middle and ends of the shaped object in a traveling
direction during shaping. The results are shown in Tables 3 and
4.
(2) Shrinkage
[0094] The flat-plate shaped objects produced under the conditions
in Tables 3 and 4 were measured in terms of shrinkage. The
shrinkage was measured in the build-up direction and the traveling
direction. The shrinkage in the build-up direction is a shrinkage
in the thickness b along the build-up direction during shaping
shown in FIG. 5. The shrinkage in the traveling direction is a
shrinkage in the length a along the traveling direction during
shaping shown in FIG. 5. The results are shown in Tables 3 and
4.
(3) Interface Adhesion
[0095] The flat-plate shaped objects produced under the conditions
in Tables 3 and 4 were cut along the build-up direction into 10
mm-wide strips, the obtained strips were measured in terms of
bending stress by a 30 mm-span three-point bending test with a
tester Autograph AG-5000 (manufactured Shimadzu Corporation), and
the measured values were assumed as interface adhesions. The
results are shown in Tables 3 and 4.
(4) Tensile Strength
[0096] Dumbbell tensile specimens produced under the conditions in
Tables 5 and 6 were measured in terms of tensile strength with a
tester Autograph AG-1 (manufactured by Shimadzu Corporation). The
results are shown in Tables 5 and 6.
(5) Flexural Strength and Flexural Modulus
[0097] Bending specimens produced under the conditions in Tables 7
and 8 were measured in terms of flexural strength and flexural
modulus by a 60 mm-span three-point bending test with a tester
Autograph AG-5000 (manufactured by Shimadzu Corporation). The test
results are shown in Tables 7 and 8.
TABLE-US-00003 TABLE 3 Comp. Comp. Comp. Comp. Test Test Test Test
Test Test Test Test Ex. 1 Ex. 2 Ex. 3 Ex. 4 Ex. 1 Ex. 2 Ex. 3 Ex. 4
Materials used Ex. 1 Ex. 2 Ex. 3 Ex. 4 Comp. Comp. Comp. Comp. Ex.
1 Ex. 2 Ex. 3 Ex. 4 Shaping nozzle temperature (.degree. C.) 250
250 250 250 210 250 250 250 conditions heated bed temperature
(.degree. C.) 30 30 30 30 30 30 30 30 layer height (mm) 0.5 0.5 0.5
0.5 0.5 0.5 0.5 0.5 head feed speed (mm/sec) 30 30 30 30 30 30 30
30 Properties amount of warpage (mm) 1.2 0.4 0.3 2.0 3.1 3.0 3.0
1.9 shrinkage in build-up direction (%) 0.32 0.18 0.02 0.08 0.64
0.61 0.54 0.43 shrinkage in traveling direction (%) 1.2 0.72 0.56
1.1 5.3 5.1 4.9 2.3 interface adhesion (MPa) 59 68 60 58 50 48 47
44
TABLE-US-00004 TABLE 4 Comp. Comp. Comp. Comp. Test Test Test Test
Test Test Test Test Test Test Test Ex. 5 Ex. 6 Ex. 5 Ex. 7 Ex. 8
Ex. 6 Ex. 9 Ex. 7 Ex. 10 Ex. 11 Ex. 8 Materials used Ex. 5 Ex. 6
Comp. Ex. 7 Ex. 8 Comp. Ex. 9 Comp. Ex. 10 Ex. 11 Comp. Ex. 5 Ex. 6
Ex. 7 Ex. 8 Shaping nozzle temperature (.degree. C.) 250 250 250
230 230 230 230 220 265 265 265 conditions heated bed temperature
(.degree. C.) 30 30 30 80 80 80 85 85 30 30 30 layer height (mm)
0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 head diameter (mm) 0.5
0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 head feed speed (mm/sec) 30
30 30 30 30 30 30 30 30 30 30 Properties amount of warpage (mm) 0.5
0.3 2.9 0.8 0.5 1.5 0.1 0.8 1.5 0.9 3.8 shrinkage in build-up 0.21
0.09 0.58 0.18 0.15 0.88 0.6 1.0 0.58 0.23 1.1 direction (%)
shrinkage in traveling 0.79 0.84 4.8 0.10 0.08 0.28 0.04 0.25 1.42
0.96 6.21 direction (%) interface adhesion (MPa) 75 77 81 41 42 35
25 19 82 88 52
[0098] Tables 3 and 4 show that Test Examples 1 to 11 in which
inorganic fibers were blended with PA12 resin, PAMXD6 resin ABS
resin, COC resin or PBT resin exhibited significantly low amounts
of warpage and significantly low shrinkages both in the build-up
direction and traveling direction as compared to Comparative Test
Examples 1 to in which no inorganic fibers were blended with PA12
resin, PAMXD6 resin, ABS resin, COC resin or PBT resin.
Furthermore, it is shown that their interface adhesions were
significantly improved.
[0099] As is obvious from comparison of Comparative Test Example 1
with Comparative Test Examples 2 to 4, the addition of an inorganic
additive, such as carbon black or talc, into a thermoplastic resin
generally decreases the interface adhesion. However, for example,
comparison of Test Examples 1 to 4 with Comparative Test Example 1
shows that the addition of the inorganic fibers according to the
present invention into a thermoplastic resin offered an unforeseen
effect of increased interface adhesion.
TABLE-US-00005 TABLE 5 Comp. Comp. Comp. Comp. Test Test Test Test
Test Test Test Test Ex. 12 Ex. 13 Ex. 14 Ex. 15 Ex. 9 Ex. 10 Ex. 11
Ex. 12 Materials used Ex. 1 Ex. 2 Ex. 3 Ex. 4 Comp. Comp. Comp.
Comp. Ex. 1 Ex. 2 Ex. 3 Ex. 4 Shaping nozzle temperature (.degree.
C.) 250 250 250 250 210 250 250 250 conditions heated bed
temperature (.degree. C.) 30 30 30 30 30 30 30 30 layer height (mm)
0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 head diameter (mm) 0.5 0.5 0.5 0.5
0.5 0.5 0.5 0.5 head feed speed (mm/sec) 30 30 30 30 30 30 30 30
Properties tensile strength (MPa) 60 64 74 60 57 52 43 50
TABLE-US-00006 TABLE 6 Comp. Comp. Comp. Comp. Test Test Test Test
Test Test Test Test Test Test Test Ex. 16 Ex. 17 Ex. 13 Ex. 18 Ex.
19 Ex. 14 Ex. 20 Ex. 15 Ex. 21 Ex. 22 Ex. 16 Materials used Ex. 5
Ex. 6 Comp. Ex. 7 Ex. 8 Comp. Ex. 9 Comp. Ex. 10 Ex. 11 Comp. Ex. 5
Ex. 6 Ex. 7 Ex. 9 Shaping nozzle temperature (.degree. C.) 250 250
250 230 230 230 230 220 265 265 265 conditions heated bed
temperature (.degree. C.) 30 30 30 80 80 80 85 85 30 30 30 layer
height (mm) 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.5 0.5 0.5 head
diameter (mm) 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 head feed
speed (mm/sec) 30 30 30 30 30 30 30 30 30 30 30 Properties tensile
strength (MPa) 90 107 72 46 50 39 53 48 54 65 46
[0100] Tables 5 and 6 show that Test Examples 12 to 22 in which
inorganic fibers were blended with the resin also exhibited high
tensile strengths as compared to Comparative Test Examples 9 to 15
in which no inorganic fibers were blended with the resin.
TABLE-US-00007 TABLE 7 Comp. Comp. Test Test Test Test Test Test
Ex. 23 Ex. 24 Ex. 25 Ex. 26 Ex. 17 Ex. 18 Materials used Ex. 1 Ex.
2 Ex. 3 Ex. 4 Comp. Comp. Ex. 1 Ex. 4 Shaping nozzle temperature
(.degree. C.) 250 250 250 250 210 250 conditions heated bed
temperature (.degree. C.) 30 30 30 30 30 30 layer height (mm) 0.2
0.2 0.2 0.2 0.2 0.2 head diameter (mm) 0.5 0.5 0.5 0.5 0.5 0.5 head
feed speed (mm/sec) 30 30 30 30 30 30 Properties flexural strength
(MPa) 52 58 73 54 48 54 flexural modulus (GPa) 1.7 2.1 3.2 1.8 1.3
2.4
TABLE-US-00008 TABLE 8 Comp. Comp. Comp. Comp. Test Test Test Test
Test Test Test Test Test Test Test Ex. 27 Ex. 28 Ex. 19 Ex. 29 Ex.
30 Ex. 20 Ex. 31 Ex. 21 Ex. 32 Ex. 33 Ex. 22 Materials used Ex. 5
Ex. 6 Comp. Ex. 7 Ex. 8 Comp. Ex. 9 Comp. Ex. 10 Ex. 11 Comp. Ex. 5
Ex. 6 Ex. 7 Ex. 8 Shaping nozzle temperature (.degree. C.) 250 250
250 230 230 230 230 220 265 265 265 conditions heated bed
temperature (.degree. C.) 30 30 30 80 80 80 85 85 30 30 30 layer
height (mm) 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.5 0.5 0.5 head
diameter (mm) 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 head feed
speed (mm/sec) 30 30 30 30 30 30 30 30 30 30 30 Properties flexural
strength (MPa) 132 187 114 72 72 51 83 80 82 115 69 flexural
modulus (GPa) 4.6 6.8 2.6 3.8 5.9 1.7 4.3 2.1 3.7 5.8 2.1
[0101] Tables 7 and 8 show that Test Examples 23 to 33 in which
inorganic fibers were blended with the resin also exhibited high
flexural strengths and flexural moduli as compared to Comparative
Test Examples 17 and 19 to 22 in which no inorganic fibers were
blended with the resin. Comparative Test Example 18 in which platy
particles were blended with the resin exhibited high flexural
strength and flexural modulus but was shown from Tables 3 and 5 not
to have increased the shrinkages, interface adhesion, and tensile
strength.
<Production of Resin Composition and Resin Powder>
(Example 12 and Comparative Examples 9 to 10)
[0102] Materials were melt-kneaded in each composition ratio shown
in Table 9 using a biaxial extruder to produce pellets. The
cylinder temperature of the biaxial extruder was 270.degree. C. to
300.degree. C. The obtained pellets and polyethylene oxide were
melt-mixed at 280.degree. C. to 300.degree. C. and the resultant
mixture was immersed in water to dissolve polyethylene oxide in
water, thus obtaining spherical resin powder. The average particle
diameter of the spherical resin powder was measured with a laser
diffraction particle size distribution measurement device
(SALD-2100 manufactured Shimadzu Corporation). The average particle
diameters of Example 12, Comparative Example 9, and Comparative
Example 10 were 70 .mu.m, 50 .mu.m, and 50 .mu.m respectively.
TABLE-US-00009 TABLE 9 Ex. Comp. Comp. 12 Ex. 9 Ex. 10 Inorganic
fibers potassium titanate % by mass 20 Thermoplastic resin PPS
resin % by mass 80 100 50 Other additives glass beads % by mass
50
<Production of Three-Dimensional Shaped Object Based on Powder
Bed Fusion Process
(Test Examples 34 and Comparative Test Examples 23 to 24)
[0103] The spherical resin powder obtained in each of Example 12
and Comparative Examples 9 to 10 was produced into a bending
specimen having a shape shown in FIG. 4 by a powder bed fusion
based three-dimensional printer (manufactured by ASPECT Inc., trade
name: RaFaEl II 150-HT) under the associated printing conditions
shown in Table 10.
<Evaluation>
(1) Amount of Warpage
[0104] The shaped objects of bending specimens produced under the
conditions in Table 10 were measured in terms of amount of warpage
with a non-contact roughness and shape measurement device (a
one-shot 3D shape measuring microscope VR-3000 manufactured by
Keyence Corporation). The amount of warpage W is, as shown in FIG.
6, a difference in height along a build-up direction during shaping
between the middle and ends of the bending specimen. The results
are shown in Table 10.
(2) Shrinkage
[0105] The shaped objects of bending specimens produced under the
conditions in Table 10 were measured in terms of shrinkage. The
shrinkage was measured in the build-up direction. The shrinkage in
the build-up direction is a shrinkage in the thickness of the
bending specimen along the build-up direction during shaping.
(3) Interface Adhesion
[0106] Respective flexural strengths of the shaped objects of
bending specimens produced under the conditions in Table 10 were
divided by their respective packing densities and the obtained
values were assumed as interface adhesions. The packing density
value obtained by dividing the specific gravity of the shaped
object of each bending specimen the density of an injection-molded
piece (a piece of the same shape injection-molded using pellets
having the same composition). The flexural strength of the shaped
object of each bending specimen obtained by the powder bed fusion
process is the sum of interface strengths between powder particles.
As the packing density decreases, the interface area
correspondingly decreases and the flexural strength also
correspondingly decreases.
[0107] The flexural strength was obtained by measuring each bending
specimen produced under the conditions in Table 10 in terms of
bending stress by a 60 mm-span three-point bending test with a
tester Autograph AG-5000 (manufactured by Shimadzu Corporation).
The specific gravity of each shaped object was measured in
conformity to JIS Z8807.
(4) Flexural Strength
[0108] The shaped objects of the bending specimens produced under
the conditions in Table 10 were measured in terms of flexural
strength by a 60 mm-span three-point bending test with a tester
Autograph AG-5000 (manufactured by Shimadzu Corporation). The test
results are shown in Table 10.
TABLE-US-00010 TABLE 10 Comp. Test Comp. Test Test Ex. 23 Ex. 24
Ex. 34 Comp. Comp. Materials used Ex. 12 Ex. 9 Ex. 10 Shaping laser
power (W) 11 11 11 conditions feed temperature (.degree. C.) 240
240 240 part temperature (.degree. C.) 250 250 250 layer height
(mm) 0.1 0.1 0.1 Properties amount of warpage (mm) 2.1 3.9 3.2
shrinkage (%) 0.9 1.5 1.1 interface adhesion (MPa) 97 84 48
flexural strength (MPa) 92 80 46
* * * * *