PODIUMCOMMUNICATIONSDevelopment of a base makeup with a pearl luster using
three-dimensional computer graphics
Akinori Inoue1, Kensuke Tobitani2, Yasunori Osawa3, Minori Fujiwara1, Lisa Park2,
Kohsuke Nishimoto3, Noriko Nagata2, and Akihiro Okada1
1

Naris Cosmetics Co., Ltd., 11-17, 1-chome Ebie, Fukushima-ku, Osaka 553-0001, Japan
Kwansei Gakuin University, 2-1, Gakuen, Sanda, Hyogo 669-1337, Japan
3
Nihon koken kogyo Co., Ltd., 6-1-2, Ichibancho, Tachikawa, Tokyo 190-0033, Japan
2

Short summary
Pearls have long attracted attention for their elegant beauty. In this study, we attempt
to formulate a base makeup that gives a pearl-like luster to human face. Applying an
optical property of pearls called “blurring” to face images reproduced inthree-dimensional computer graphics (3DCG) increased the visual appeal. Therefore, inthis study, we formulated a base makeup that imparts blurring to a real human face.
Initially, the reflective characteristics of blurring were calculated simulating thereflection and transmission of light in a multilayer structure of thin films. As such, wedeveloped a powder ingredient having a similar bidirectional reflectance distributionfunction (BRDF), which defines how light is reflected from object surfaces with alayered structure. The powder ingredient was a plate-like powder composed of synthetic
mica with titanium dioxide and aluminum hydroxide. Although it had high reflectance,
it did not produce an unnatural finish to the face. We subsequently formulated a basemakeup that contained the powder described above. Then extracted BRDF and surface
reflection light components from a 3DCG face image as reflection characteristics andcompared these characteristics with those of a Bio Skin Doll (Beaulax, Japan) with the
makeup. Applying a prototype base makeup to the Bio Skin Doll increased the lightreflectance of whole face and produced reflectance properties similar to the human face
image on which blurring was applied.
1. Introduction
The attractive quality of pearls lies in their smooth luster and deep gloss due tocomplex optical phenomena related to their multilayer structure. In this study, we
attempt to apply the luster of pearls to a base makeup. Until now, we performed visualevaluations using facial 3DCG taking into account optical phenomena observed inpearls and a multiple regression analysis of the degree of optical “blurring” and“interference light” components. Data revealed that “blurring” was the most influential
factor, with the most attractive image generated when it alone was used. The pearly skin201

PARIS 2014 28 CONGRESS October 27 to 30
th

th

th

PODIUM
COMMUNICATIONS

image in Figure 1 shows the most attractive image. [1][2][3][4].

Figure 1. Facial 3DCG image of pearly skin.
Many studies have examined the application of the luster of pearls to cosmetics. For
example high-brightness powder ingredients, such as pearly powder, consist of synthetic
mica and titanium dioxide [5]. In many cases, cosmetics that intend to impart luster of
pearls are predominantly composed of powder with high reflectance or any ingredients
derived from pearls, like shell powder.
Therefore, in this study, we focus attention on optical characteristic of the pearls andattempt to identify, by using the 3DCG technology, reflective characteristics of thehuman face on which luster of pearls is applied and to formulate a base makeup that
impart similar reflective characteristics to real human face. The initial step was todevelop a powder ingredient embodying the reflective characteristics of blurring. The
subsequent step was to formulate a base makeup which, when applied to a Bio Skin
Doll, embodied similar reflective characteristic to the pearly skin image. The reflective
characteristics of the pearly skin image at the microscopic level were evaluated using
the BRDF. In addition, the specular reflection of this image at a macroscopic level was
determined through multiperspective light imaging.
2. Development of the pearly blurring powder (PB powder)
2.1. Structure of the powder ingredient
The BRDF of blurringcalculated by physical simulation
using the Monte Carlo method
shows the lowest reflectance at a45°

incident

angle

while

distorting to the right with anincreasing incident angle (Figure2). The figure demonstrates
higher reflectance affected by the
Fresnel reflection.

Figure 2.
Fi
2 BRDF off blurring.
bl i

202

PODIUM
COMMUNICATIONS

We developed a powder ingredient having similar BRDF to the blurring of pearls.
Generally, powder ingredients show different reflective characteristics depending on
particle composition and shape. Particularly for plate-like particles, reflectance is known
to increase with particle size.
Since the BRDF of blurring exhibited a strong specular reflection, we designed apowder having high reflectance. However, when a large particle powder ingredient withhigh reflectance was used in the base makeup composition, the size and reflectanceintensity caused unnatural finish. Therefore, for the ingredient embodying the BRDF of
pearls blurring, we designed a powder which based on synthetic mica with a particle
size of about 20 ȝm. To increase the reflection intensity, it was coated with titanium
dioxide and aluminum hydroxide. We subsequently named this powder as Pearly
Blurring powder (PB powder).
2.2. Evaluation methods
The BRDF of blurring was calculated taking
into account all the reflections and transmissions
in a multilayer structure, as shown in Figure 3.
This structure simulates the multilayers of apearl.
Therefore, the evaluation of powders in a
multilayer structure should be performed. For thisFigure 3. Multilayer structure
simulated for calculation of
BRDF.

reason, a multilayer powder structure was createdon a coating paper using a 50% octyl dodecanol ethanol solution as the binder. In orderto make the multilayer powder structure, the powder was overlayered and flattened by aroller. This process was repeated until the surface of coating paper was covered
completely, as shown in Figure 4.
The BRDF of this sample wasobtained by taking measurementswith an optical gyro measuringmachine (OGM) [6]. The powder
was evaluated by comparing its
BRDF with the BRDF of blurring.
Comparison of the BRDFs was
conducted at incident angles of 0°,22°, 45°, and 67°. In addition to thePB

203

powder,weevaluate

mica,

Figure 4. Forming a multilayer structure of
the powder ingredient.

PARIS 2014 28 CONGRESS October 27 to 30
th

th

th

PODIUM
COMMUNICATIONS

synthetic mica, and large particle powder, the so called pearly powder. Table 1 showsfeatures of the powders.
Table 1. Features of powders evaluated.

2.3. Results and discussion
The BRDF of blurring, shown in Figure 5(a), was compared with the BRDFs of thepowder (Figure 5), mica (Figure 5(b)), synthetic mica (Figure 5(c)), pearly powder(Figure 5(d)), and PB powder (Figure 5(e)).

Figure 5. BRDFs of powders.
In order to evaluate the similarity of pearl blurring and powder BRDFs, we calculated
the peak value locus showing the relative value of the reflection peak at each incident
angle, with the reflection peak at 67° set as 1. We subsequently calculated the full widthat half maximum (FWHM). In the graph, the peak sharpens as the FWHM decreases.
In addition, we calculated residual sum of squares (RSS) between the BRDF ofblurring and the BRDF of powders that were fitted to the BRDF of blurring for theentire range of incident angles. The results are shown in Table 2.

204

PODIUM
COMMUNICATIONS

Table 2 Analysis of BRDFs

Comparing BRDF of blurring with BRDF of powders at the peak value locus, mica
and synthetic mica showed lower reflectance at 0°, 22°, and 45° compared to at 67°. On
the other hand, pearly powder and PB powder exhibited higher reflectance at 0°, 22°,and 45°. In addition, comparing the FWHM, mica and synthetic mica had higher values
due to a broad peak form. On the other hand, the pearly and PB powders show lower
values because of their sharp peak form. Additionally, in the comparison of RSS, pearlyand PB powders had lower values than mica and synthetic mica, indicating that the
BRDF of pearly powder and PB powder are closer to the BRDF of blurring.
The above results suggest that mica and synthetic mica are not suitable ingredients to
impart blurring. Moreover, despite pearly powder showing a close BRDF to that ofblurring, it is not practical since the particle size is too large to be contained incosmetics. PB powder on the other hand, exhibited a closer BRDF value to that ofblurring in all analyses, and therefore more appropriately embodies the reflective
characteristic of blurring than other powders.
2.4. Sensory evaluation
2.4.1. Evaluation of luster and attractiveness of the PB powder
We conducted sensory evaluation of powders formed in multilayer structures in two
ways. The first was whether the powder exhibited “luster of pearls” and the second waswhether the powder was “attractive”. Each powder was evaluated by 44 women, from21 to 49 years old (32.2 ± 7.53, mean ± SD). First, the evaluators selected the powders
by a multiple-choice test, with ratings out of 5, then they selected one powder in asingle-answer test.

205

PARIS 2014 28 CONGRESS October 27 to 30
th

th

th

PODIUM
COMMUNICATIONS

2.4.2. Result and discussion
Evaluation of the “luster of pearls” (Figure 6(a)) shows that the rating value of PB
powder was 2.9, which is highest among all powders. Furthermore, Figure 6(b) showsthat PB powder was selected by 61% of the respondents in the multiple-choice response,and in the subsequent single-answer question, as shown in Figure 6(c), PB powder was
selected by 48% respondents.
For the evaluation of “attractiveness,” PB powder also showed a high rating value of 3.7(Figure 7(a)) significantly and 55% respondents selecting it in the multiple-choice
response (Figure 7(b)). Moreover, as shown in Figure 7(c), in the single-answer test, theselective rate of PB powder was 45%.
From the above results, it was shown visually that the PB powder has the luster of
pearls than other powders and that the luster of PB powder is considered attractive.

Figure 6. Rating value of “luster of pearls”.
*P < 0.05, **P < 0.01 by Steel’s test.

Figure 7. Rating value of “attractiveness”.
*P < 0.05, **P < 0.01 by Dunnett's test.
3. Development of the base makeup embodying the pearly skin3.1. Formulation of the base makeup
We formulated a liquid-type foundation containing 20% PB powder as base makeup,
which embodied similar reflective characteristics to the pearly skin image when applied

206

PODIUM
COMMUNICATIONS

to the Bio Skin Doll. The base makeup containing the PB powder was then evaluated in
two distinct ways, using mica as a control. The first was by a comparison of BRDFs,
and the second was by a comparison of the specular reflection component.
3.2. Evaluation of the base makeup by BRDF comparison
3.2.1. Evaluation methods
The BRDF of the pearly skin image was calculated using rendered images. Figure 8
shows the schematic of BRDF measurement. These images were obtained by setting thelight and camera at an arbitrary angle with respect to the plane in which the opticalcharacteristics of the pearly skin image were applied in the CG space. The image
luminance value was considered as the reflection intensity at the optical acceptanceangle of the incident light source.
The base makeup was applied to the
Bio Skin Plate for evaluation and its
BRDF was measured using OGM. The
embodied blurring was evaluated at
the microscopic level by comparing
Bio Skin Plate and pearly skin images.

Figurei
8.
8 SchematicS
i off BRDF
measurements in the CG.

3.2.2. Results and discussion
Since the “blurring” component was added to the entire face image, the pearly skin
image BRDF (Figure 9(a)) exhibited a high value for the entire acceptance angle,
regardless of the incident angle. It was also found that the specular reflection componentof each incident angle was slightly added at regular reflection angle in acceptance angle.
On the other hand, the BRDF of Bio Skin Doll with base makeup containing mica
(Figure 9(c)) did not have much increased reflection intensity at any incident angle, ascompared with the BRDF of Bio Skin Doll without anything applied, as shown in
Figure 9(b).
However, for the Bio Skin Doll with base makeup containing PB powder (Figure9(d)), the BRDF was close to that of the pearly skin image since the reflectanceintensity increased for the entire acceptance angle range and the specular reflection
component was added.

207

PARIS 2014 28 CONGRESS October 27 to 30
th

th

th

PODIUM
COMMUNICATIONS

Figure 9. BRDFs of Bio Skin Doll.
We calculated the RSS between BRDFs of the pearly skin image and Bio Skin Doll,fitted to the BRDF of the pearly skin image at the entire incident angle range.
The RSS of the BRDF for Bio Skin Doll with base makeup containing mica was 9.35,
whereas the RSS of the BRDF for Bio Skin Doll with base makeup containing PB
powder was 4.83. It is therefore evident that the BRDF for the Bio Skin Doll with basemakeup containing PB powder was closer to the BRDF for pearly skin image than the
BRDF for the Bio Skin Doll with the base makeup containing mica.
3.3. Evaluation of the base makeup by comparison of the specular reflectancecomponent
3.3.1. Evaluation methods
Blurring results from the light spreading caused by repeated regular reflection andspecular transmission in the multilayer pearl structure. Therefore, blurring was
configured as a specular reflection component in the pearly skin image. Itscharacteristics were elucidated by extracting the specular reflection images of the pearlyskin and Bio Skin Doll, and visualizing these reflections through multiperspective
imaging. The specular reflection image of the pearly skin image was obtained from therendered image in the absence of diffused light and subsurface-scattering components.

208

PODIUM
COMMUNICATIONS

On the other hand, the specularreflection image of the Bio Skin Dollwas extracted by processing the image
using polarized light (PL), as shown in
Figure 10 [7].
The embodied blurring was evaluatedat the macroscopic level by comparing
specular reflection image of the pearlyskin image and Bio Skin Doll at
multiple perspectives in which incident
and acceptance angles are paired with
0°, 22°, 45°, and 67°.

Figure 10. Extraction of the specularreflection. component from Bio Skin Doll .

3.3.2. Results and discussion
Figure 11 shows the specular reflection images from multiple perspectives, whichwere converted to heat map displays based on the luminance value. Figures 11(a) to11(d) show specular images of pearly skin, Bio Skin with nothing applied, Bio Skin
with mica applied, and Bio Skin with PB powder applied, respectively. We evaluatedthe changes in face luminance, and the average for the luminance for the entire face
image was calculated (Figure 12).
For almost all combinations of incident angles and acceptance angles, the reflectanceintensity of the pearly skin image was higher than that of the Bio Skin Doll with nothing
applied. On the other hand, the specular reflection component of Bio Skin Doll withbase makeup containing mica slightly increased for all combinations of incident angles
and acceptance angles relative to Bio Skin Doll with nothing applied.
However, using the specular reflection component of Bio Skin Doll with the basemakeup containing PB powder, the luminance of entire face for all combinations ofincident angles and acceptance angles increased more than that of mica. The luminanceof entire face with the base makeup containing PB powder particularly increased atlower incident angles, as shown in Figure 12.
For the above reasons, the application of the base makeup containing PB powder to
Bio Skin doll most closely represented the pearly skin face image.

209

PARIS 2014 28 CONGRESS October 27 to 30
th

th

th

PODIUM
COMMUNICATIONS

Figure 11 Distribution of the specular reflection component on face images.

Figure 12 Average luminance of face images at each incident angle.

210

PODIUM
COMMUNICATIONS

3.4. Sensory evaluation of base makeup
3.4.1. Evaluation of the Bio Skin Doll
Forty-four Japanese women, from 21 to 49 years old (32.2 ± 7.53, mean ± SD)
conducted the sensory evaluations. They visually evaluated the Bio Skin Doll to which
we applied base makeup containing mica or PB powder. First, they gave a rating out of
5 on the basis of how closely the Bio Skin Doll resembled the pearly skin image andselected which bears more resemblance. Then, they gave a rating out of 5 on theattractiveness of the Bio Skin Doll and selected which is more attractive.
3.4.2. Results and discussion
Figure 13 (a) indicated that the rating value of the Bio Skin Doll with base makeup
containing PB powder was 3.3, which is significantly higher than that of mica.
Moreover, the selective rate is higher (Figure 13(b)). Furthermore, the rating value for
attractiveness was 3.3, which is higher than that of mica (Figure 14(a)). In addition, theselective rate is higher (Figure 14(b)).
These results indicated that base makeup containing PB powder is considered to beable to impart more luster of blurring to the Bio Skin Doll than traditional base makeup.

Figure 13. Resemblance evaluation to the pearly skin image.
*p<0.05, **p<0.01 by Student’s t test.

211

PARIS 2014 28 CONGRESS October 27 to 30
th

th

th

PODIUM
COMMUNICATIONS

Figure 14. Rating value of attractiveness.
*p<0.05, **p<0.01 by Student’s t test.
4. Conclusion
In this study, we focused on the blurring that enhances the attractiveness of humanface images by applying the optical property of pearls, and we subsequently developed abase makeup embodying the luster of blurring for the human face.
For the ingredient embodying blurring, we developed a complex powder consistingof synthetic mica, titanium dioxide, and aluminum hydroxide. The developed PB
powder exhibited similar reflective characteristic to pearl blurring. The BRDF of thepowder multilayer structure was similar to BRDF of blurring that was simulated basedon the multilayer structure of pearls. Furthermore, the base makeup containing PB
powder increased the reflective intensity of the Bio Skin Doll face on the whole.
Therefore, based on comparisons of BRDF, specular reflection component, and sensory
evaluation, applying this base makeup to Bio Skin Doll embodied the reflective
characteristics of the pearly skin image and closely resembled the pearly skin image
visually. As such, the optical properties can be claimed to be similar to that of the target
pearly skin image. In summary, we formulated a base makeup that can achieve the luster
generated by the pearls “blurring” component. This newly developed formulation makes
it possible to provide the luster of pearls to human skin.
5. References[1] N. Nagata, T. Dobashi, Y. Manabe, T. Usami, S. Inokuchi: IEEE Trans. Visual.
Comput. Graphics, vol. 3, pp. 307–315, Oct./Dec. 1997.
[2] T. Dobashi, N. Nagata, Y. Manabe, S. Inokuchi: IEEE/ASME Transactions on
Mechatronics, vol. 3, no. 2, pp. 106–112, June 1998.
[3] K. Tobitani, A. Okada, K. Nishiyama, A. Ishida, L. Park, N. Nagata:19th
Korea-Japan Joint Workshop on Frontiers of Computer Vision, pp.107-112, Jan./Feb.

212

PODIUM
COMMUNICATIONS

2013[4] K. Nishiyama, K. Tobitani, A. Ishida, L. Park, N. Nagata, A. Okada: Proceedings ofthe 22nd IFSCC Conference, pp. 190–191, 2013[5] M. Yamamoto: Fragrance Journal, vol. 27, no. 1, pp.137–144, 1999
[6] OGM: BRDF measuring device, Digital Fashion Ltd,
<http://www.digitalfashion.jp/new/product/LSC/OGM/> (accessed Jun 24th)[7] Y. Masuda, N. Kunizawa, M. Takahashi: J. Soc. Cosmet. Chem. Japan., vol. 39, pp.
201–208, 2005

213