2015_all slides

Biomaterial Science（2015 Schedule）

EG60411

Biomaterial Science
Toshiharu Enomae

Professor, PhD, Paper Device and Eco-friendly materials

2G103, 10:10-11:25, Tuesday

#

Date

1

10/6

History of papermaking

2

10/13

Pulps – Beating and fiber properties

3

10/20

Pulps – Additives and functions

4

10/27

Papermaking processes & interfiber bonding

5

11/10

Paper– Structural properties

6

11/17

Paper– Surface properties

7

11/24

Paper–Wetting and absorption properties

8

12/1

Paper– Mechanical and optical properties

9

12/8

Polysaccharide chemistry by Assoc Prof Akiko Nakagawa

10

12/15

Recent research of paper science and technology

11

12/22

Examination

Content

Lecture information and contact

Biomaterial and Biomaterial Science Homepage of “Biomaterial Science (T.

 What biomaterial is

Enomae)” http://www.enomae.com/→ Handouts in lecture(講義資料)
 E-mail address→ t@enomae.com
for any questions and visit to laboratory(Bio-Agr. Bldg. 生農C209 or 総合A618)

Materials constituting components and thestructure of organisms processed to provide
properties required for the use such as:
Wood, paper,
paper, cellophane, rubber,
rubber,leather, polylactic acid What biomaterial science ispolylactic acid

Science and technology for providing highperformance to biomaterials

Topics today“Paper” －Definition

 What is paper and paper science?

 “A thin, flat material obtained by sheet- Origin of paper History of papermaking technology
 Production of paper in the world

forming and drying fibers especially ofplants”
 “A thin, flat material made from crushedwood or cloth used especially for writing
and printing on and in packaging”- Cambridge Dict.
 Plant fibers, especially wood-sourced, as araw material of paper are called “a pulp”

Biomaterial Science by Toshiharu Enomae1

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Scope of Paper ScienceWho has affected you most?

 Colloid Sci（Fiber dispersion system）+ Applied Paper Sci

Colloid Science
Fiber dispersion

Silviculture・ Wood Chem・
Biotechnol. Pulping
Digestion

Pulp

 “Who has affected you most in your life so far?”

was voted in an internet site.
 Jesus Christ received the second largest

numbers of votes
 Ts’ai Lun（蔡倫）received
the largest.
(A)

ForestChip

Bleaching

Applied Paper Science
Printing, Packaging

Coating

Calendering

Drying Without paper, printing technology would not
Press

Wire

Inlet

have developed, nor would wealthy life today beguaranteed.

Origin of paper

Origin of paper Ts’ai Lun is traditionally The world oldest paper

regarded as the inventor of
paper. Exactly, however, heinvented the composition for
paper along with thepapermaking in A.D. 105.
 The fibrous materials used inthose day were bark, hemp,
silk, and fishing net.

蔡倫

found in that is
estimated to be between
179 and 142 BC (earlyWestern Han 漢朝).
 It was used as a map,
where mountains,
Fangmatan（放馬灘）paper
waterways and roads
are drawn.

History of papermaking tech. -Materials
MoscowEnglandUSA

Westward and eastward from China

Nuremberg 1390
Fabriano
1276
Baghdad Hemp （Cannabis大麻・ Linen亜麻）Cannabis has been used for
cloth and fishing net in China
and Japan. Linen in Europe.
Hemp Rags Recycling of cloth woven originally from
hemp. Cotton from the age of Industrial
Revolution
 Bast (skin) fibers, such as Paper Mulberryetc. for Japanese paperSamarkandTs’ai Lun 105

Improvement of paper Japan 610

Spread of papermaking technology

Biomaterial Science by Toshiharu Enomae2

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History of papermaking tech. -Materials

Origin of Printing technology

 Leaves, of Treang tree to make

Gutenberg (1395? –1468)
invented a printing press in around
1445.
The invention consisted of mass-producing movable type; oil-based ink from linseed oil; and a wooden printing press similar to
the agricultural screw presses
and allowed the mass production of
printed books and was economically
viable for printers and readers alike.

“Sastra”
 Wood, capable of producing on alarge scale Kenaf

A kind of hemp promoted forforestry preservation, but not
accepted any more.

Treang tree

Johannes Gutenberg

 Plastics, synthesized paper frompolypropylene called “Yupo”

Movable type
Sastra42-line Bible (42B) Gutenberg printed andpublished 180 copies of
42-line Bible.
 The start of the age of theprinted book in the West

The Greatest Inventions of the Past 2000 Years
Edited by John Brockman and published on Jan 12, 2000
John Brockman, a novelist of USA, asked “What is the mostimportant invention in the past two thousand years? and Why?”
to famous.
“Reading glasses” and “eraser” were unexpectedly proposed.

Many people including Dr. Philip Anderson, a Nobel prize
winner, chose “printing technology” because it promoted
knowledge occupied by privileged people to the public.
 Relationship with paper Increased paper demand Development of mass production of paper Use of wood as a papermaking material
 Invention of paper machine to produce“continuous paper”.

Another physical scientist chose “watch” for quantification oftime passage that was dependent on one’s sense so far.
“Heliocentric theory”, “mathematics”, “differential and integral
calculus”, “democracy”, and “religion” were also supported.



See http://www.edge.org/documents/Invention.html

History of papermaking tech. – Machine
1670 Hollander beater invented [Holland]
1719 Reaumur submitted his invention - paper can be madefrom wasp hives- to the Academy [France]
1798 Louis-Nicolas Robert invented manufacture of continuous
paper [France]
1844 Keller invented ground wood pulp [Germany]
1851 Burgess [USA] and Watts [England]invented soda pulping
to make wood pulp.
1856 Healey received a patent of corrugated [England]
1856 Tilghman invented the sulfite pulping [USA]1879 Dahl invented Kraft pulping [Germany]
1950 Hardwood pulping initiated[Japan]
1968 Thermo-Mechanical Pulping (TMP) Developed[Sweden]
1977 Quinone-added pulping invented [Japan]

Biomaterial Science by Toshiharu Enomae

Mechanical pulping－Groundwood pulpGP or SGW ([Stone] Groundwood Pulp)
Keller invented ground wood pulp in 1844

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Old printed material in JapanThe world oldest printed material

In 764, Emperor Koken
had holy texts (無垢浄光陀羅尼経) printed on paper
one million copies forpeace of Japan, containedin one million wooden
miniatures of a three story
tower, and laid out in theten great temples like
Horyu-temple and Todaitemple.

In 1966, printed holy
texts was discovered in
the Buddha tower of
Bukkoku-temple (仏国寺)
of Keishu, Shinra (新羅慶州), currelty Korea(韓国).
This tower is known tohave been built in 751.

The world oldest printed material

世界最古の印刷物

Paper with holy texts (華厳経)
written in 755, Silla era (新羅)was analyzed.

Biomaterial Science by Toshiharu Enomae

 755年に新羅時代の華厳経が書かれた紙

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Production of paper and paperboard
Production , million ton

12000

How to make paper From “ wood”

China
(A2)
USA

10000

Japan
(A3)
Germany

8000

CO2

ForestWood

Korea
Canada6000

SwedenForestrecycling

India
4000

FinlandWaste paper
Paper
recycling

Indonesia
2000

BrazilThailand

0

Chip

Pulp
Paper

Wood chips to pulp

Ratios of waste paper recovery and utilization
Top 10 countries of paper production（2013)
Sourced from Annual Review of Global Pulp and Paper Statistics（RISI）

Prod. orderCountry
5
Korea

Recovery, ％ Utilization, ％
96.0
87.5

3
4
6
7
2

Japan
Germany
CanadaSweden
USA

79.8
78.7
71.4
67.7
63.8

64.5
73.6
24.1
12.8
36.1

9

Finland

61.7

5.7

10

Indonesia

56.6

59.1

1
8

China
India

44.8
27.8

71.1
56.3

Wood tissue－cells of beech tree

Digestion(Cooking)

Chip

Pulp

Bleaching+ NaOH + Na2S
at 150ºC for 5 hours+ ClO2, + H2O2
at 40ºC for 2 hours

Axial parenchyma cell
Bright-field

Polarized light

Component of
hardwood tissue
Vessel20%
Wood fiber

60％

Axial
10％
parenchyma cell
Radial10％
parenchyma cell

Biomaterial Science by Toshiharu Enomae

parenchyma cells

Bast fibers

0.1 mm5

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Wood tissue－structure of cell wall
S3 layer(Secondary cell wall - 3rd layer )Cellulose microfibril

S2 layer(indicated by parallel lines)

Kind of pulp
 Pulp Fibers mainly consisting of cellulose
extracted from plant such as wood bymechanical or chemical treatment
 Mechanical pulp [MP]S1 layer

Fibers extracted from wood by crushing Chemical pulp [CP]Primary wall
Middle lamella

Fibers extracted from wood by dissolving lignin

 Deinked pulp [DIP] (recycled pulp)
Fibers extracted from waste paper by removing ink

Structure of plant cell wall and axial direction of cellulose microfibrils

Chemical pulp－Fiber geometry
Softwood pulp fiber

Chemical pulp－Fiber geometry

Hardwood pulp fiber Copy paper

consists ofhardwood pulp fibers

 Observe pulps

 Observe pulps

Wood composition－Major 3 components
Approx. ratio (%)

Hardwood

Softwood Hardwood

Cellulose

Cellulose

45

45

Hemicellulose

25

30

Lignin25

20

OthersTerpenoid
Resin acid
Fatty acidetc.

Hardwood pulp fiber Copy paper

consists of(B) wood pulp fibers

Chemicalcomponent

Softwood pulp fiber

Hemicellulose
Lignin20 %10 %Biomaterial Science by Toshiharu Enomae

Dry lap pulp2%

Others5%

Change of Compositionby kraft pulping

Slush pulp
Pulp suspension withconcentrations of approx.
1-4% Lap pulp
Pulp formed and folded bywet machine. Called “Drylap” when dried


45 %

30 %

2-8

Form of pulp

Bleached
kraft pulp
40 %Bale pulp
A bunch of pulp sheets
compressed and boundwith a wireTransported bale(C) pulp

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Disintegration - Separation into individual fibers

Standard disintegrator (defibrator)
A pulp is put in water in a steel
container with ca. 3.4 L capacity
 Stirred with a propeller mixer at
3000 min-1（rpm）
 Latency of MP should be
removed at high temperature（Latent=hidden）


Dry lap pulp(D) pulp)
Dispersed in water (slush

Pulp
Chemical

Dry
mass
30 g

Water
volume2.0 L

Revolutions
30,000Mechanical

60 g

2.7 L

60,000Q. How long should we disintegrate a chemical pulp?

Waste paper in yard

Waste paper and pulp

Belt conveyer

Disintegration in industry (pulper)

Biomaterial Science by Toshiharu Enomae

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Disintegration in industry (Drum pulper)

Floatation
 Deinking
Postflowtation

Disperser

Centrifugal

 Bleaching
Peroxide
tower

Post-flowtator
Drum pulper

Floatation (flowtator)

Beating (refining)
Post-disintegration process Process where shear stress is applied
to water-containing fibers resulting infibrillation (formation of small
filaments or fibers) on the surface
and concentrically loose structure

Beating (refining)

Beating achieves large bonded area
between fibers and thus higher paper
strength.

Difference between disintegration and beating Disintegration is a process toseparate fibers bonded orentangled, keeping fiber
characteristics
 Beating is a process to treat

mechanically individual fibers,changing fiber characteristics
Q. Why can this breaking process increase paper strength?

Biomaterial Science by Toshiharu Enomae

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Beater－PFI mill (beating)Beater－Refiner(refining)Processed by refiner

Rotor

In

Out

Motor
Blade
Disk plate
StatorOut

Rotor
Pulp slurry flow Stator

Beating － mechanism

https://www.youtube.com/watch?v=b17d6ssw8f4

Refining－movie－refiner

Effect of blades on pulp fibers during beating

Beating－change of fibers－external
external fibrillation

Beating－change of fibers－internalinternal fibrillation

External fibrillation

External fibrillation

Internal fibrillation

Internal fibrillation＝Concentric loosening(Lamellar separation)
Connection of small
pores formed by lignin
removalScanning Electron Micrographs of freeze-dried
softwood pulp fibers after beating

Biomaterial Science by Toshiharu Enomae

Lamellar separation offiber cell wall by beating9

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Evaluation of fiber properties

Beating－change of paper structure Freeness (Drainability)
 Specific surface area
 Fiber length distribution
 Distinguishment by staining
 Fiber coarseness Curl index

Unbeaten (left) and beaten (right) softwood pulp sheets
Q. How did fibers and sheets change by beating?

Evaluation of FreenessEvaluation of FreenessCanadian standard
freeness（mLCSF）



Canadian standard freenessOne L of pulp
suspension at 0.3%
and 20 ºC is poured
and the volume (mL) of
water drained from theside pipe is measured.



Q. Does CSF increase or
decrease by beating?

Nitrogen adsorption method

Water Retention Value (WRV)

Mw : Mass of pulp after centrifugation
Md : Mass of the pulp after oven drying

WRV(%) =100×(Mw－Md)/Md
Q. Calculate WRVs to 2
decimals in percentage.
Pulp

Sample
WRV, %

Bleached softwood

102

Bleached hardwood

101

TMP

139

CTMP (hardwood)122

After cent.(g) Oven dried(g) CTMP (50% HW + 50% SW)
Unbleached sulphite
0.61
0.23

SBKP beaten

124
104

SBKP unbeaten 0.59

0.28

Recycled pulp

HBKP beaten
0.54
HBKP unbeaten 0.45

0.22
0.24

Non-wood pulp

204

Never-dried Kraft pulp

114

Biomaterial Science by Toshiharu Enomae

Unbeaten pulp ca. 650 mL CSF
Beaten pulp ca. 400 mL CSF
Reasons why freenessby(E)
beating are
 More fines (small pieces of fibers)
 Fibrillation
make paths between fibers in a pulp
mat thin, winding, and long.

159

Langmuir modelAll the adsorption sites areequivalent and the surface ishomogeneous.
 Monolayer coverage No interactions between
adsorbate molecules on adjacent
sites


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Nitrogen adsorption method

Nitrogen adsorption method

Langmuir model (cont’d)

Nitrogen gas(N2)

The fractional coverage of the surface θchanges at the adsorption rate
proportional to gas pressure p and thenumber of empty sites N(1-θ).
The desorption rate proportional to Nθ.

Nitrogenmolecule

Material surface

SampleLiquid nitrogen(Coolant)

Adsorption
site

Specific surface area (SSA)
DryingmethodPaper
specimen

Length and width of fibers

BET SSA, m2/g

Unbleached Spruce KP
Bleached Spruce KP
Solvent
Spruce α-cellulose
exchange
Spruce GP
Birch KP
Evaporation Unbonded pulp fibers
at 105 °C
Paper
KP=kraft pulp, GP=ground wood pulp

Softwood tracheid

230
185
185
25
129
1.2
0.5 ̶ 1.0

Hardwood fiber
Hardwood vessel

1 mm

Fiber length and width distribution

Fiber length and width distribution
CCD camera
0.5 mm
Water

Water

Fiber tester, ABB(L&W), Sweden

Biomaterial Science by Toshiharu Enomae

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Fiber length and width distribution

Fiber length and width distributionlProjected area A
True length L

Width =

Shape factor =(Linearity)

Example of captured image

Projected length ℓTrue length L

Mean fiber length

Mean fiber lengthCopy paper

Comparison in fiber length between shredded
and unshuredded copy papers
40
Shredded

Measurement
Ratio (%)

ShredderUnshredded

30

1.76 mm20

Unshredded

2.06 mm100

Shredded

0

5 mm wide each

繊維長分布
l

i番目のグループに、繊維長liの繊維がn本あるとすると、
L1 = 長さ平均ポリマーのL2 =

重量平均分子量に
重量平均分子量に相当 長さ-長さ平均

繊維長 L3ポリマーのz平均分子量
平均分子量に平均分子量に相当

L3 =



A
2l

∑n l
∑n

i i

A

i

繊維長 L2

2

3

4

5

6

7

Fiber length (mm)

平均繊維長

 繊維長計算法

 数平均繊維長 L1

1

Dispersed
in water

∑n l
∑n l

L 1 L1 = ∑ i i

2A

∑

L2 =

重量平均分子量に
重量平均分子量に相当

L3Biomaterial Science by Toshiharu Enomae

2L

3L

(1)

W

ni

∑ n L (2)
∑n L
i

i

i

i

3. 長さ-長さ平均
 ポリマーの

4A

W

2

L2

繊維長

3

i i
2

nL

L

2. 長さ平均 ポリマーのi i

i i

1. 数平均繊維長

繊維長

2

i i

∑n l
∑n l

繊維長計算法i番目のグループに、繊維長Liの繊維がni本あるとすると、z平均分子量
平均分子量に平均分子量に相当

L3 =

∑n L
∑n L
i

i

3

i
i

2W

3W

(3)

2

2D 2W

3W 3D

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Effect of beating on paper properties
 LSC decreases asfiber bonding area
increases.
 Interfiber bondingarea can beevaluated by SSA.
 Beating increased
interfiber bondingarea.

 Beating increased Wet Fiber Flexibility(WFF)
Bending strengthof single wet fibers
was measured for
determination of
WFF.
 SR = SchopperRiegler method for
determination ofdrainability


Wet fiber flexibility, 1/Nm2

CoefficientLight scattering coefficient,, m2/kg

 Specific Surface Area on Light Scattering

Effect of beating on paper properties

BET surface area, m2/kg

Beating degree, SR-number

Effect of beating on paper properties

Effect of beating on paper properties Beating increased Density and Modulus of Beating increased Stretch at Break (SAB) to

Elasticity (MOE)

F=kx

2x

certain degree
 SAB increased

with as well, butleveled off.

Low beating degree

Stretch at break, %Linear relationshipbetween density
and MOE
regardless ofbeating degree

Elastic modulus, GPak; spring
constant
= MOE

x
F
2F

Density, kg/m3

Stock preparation－ additives

High beating degree

Additives－size and filler

 Paper quality control

Size (sizing agent) - water repellency
Filler - brightness and opacity
 Strength agent – dry or wet strength Dye – optical brightening agent (OBA)

Acidic paper
Size (sizing
agent)

 Paper manufacturing control

Retention aid – ex. aluminum sulfate –fines, fillers, and size retained more Antiseptic (preservative)

Density, kg/m3

Retention
aid
FillerNon-acidic paper

Rosin（Abietic acid) Alkyl ketene dimer （AKD）,
Alkenyl succinic anhydride（ASA）
Aluminum sulfate Cationic polymer such as(alum),Polyamine-amide
deteriorates paper epichlorohydrin (PAE)
Clay, Titan dioxide, Calcium carbonate, Titan
Talkdioxide

pH at
4.5～5.5
papermaking

7.5～8.5(7 or slightly greater)

Q. Why is calcium carbonate not used for acidic paper?

Biomaterial Science by Toshiharu Enomae

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Additives－size and filler

Additives – deterioration of acidic paper
Aluminum sulfate deteriorates paper.

Rosin (abietic acid)
AKD

Al２(SO4)3 + 2H2O → 2Al(OH)2+ + 2H+ + 3SO42CH2OHO
OH+[ C (CH 2)4 C NH (CH 2)2 N (CH 2)2 NH ]n
O

O

ASA
PAE

OH

O

C=O

C=O

NH2

O

O

OH

OH
CH2OH
H
O
OH
HO
OH

Cationic starch
CH2OH
O
OH
CH3
O
CH2-CH2-N+-CH3

CH2-CH2-N+-CH3

CH3

CH3

Cationic polyacrylamide

Cationic starch

Papermaking－approach section

抄紙－ワイヤーパート

Pressurized screen Head box

 ワイヤ(網）を使ってろ過作用によって紙料から脱水す

Wire (Fourdrinier )Centrifugal cleaner

白水 waterWhite

Secondary screen
Fanpump Wirepit

Machinechest

る工程 ワイヤの種類


PETのプラスチックワイヤ (以前はブロンズ製）
サテン織


Inlet

Beaten pulp
Broke
AdditivesO

Acid hydrolysis↓
Deteriorationof paperNon-acidic paper

CH3

Secondary cleaner

O

Papermaking – Additives - movie

Additives－size and filler (2)CH2CH n CH2CH

+ H2O

CH2OH
O OH, HOH
OH

Acidic paper
Strength Cationic polyacrylamide(C-PAM)
resin

CH2OH
O
OH

Paper
product
Broke

RecycleBiomaterial Science by Toshiharu Enomae

Markets
Consumers
Waste
paper



1本の横糸の上、3本の横糸の下を縦糸が通る。縦糸の磨
耗防止

二重織


上層が微細繊維の歩留まり向上、下層が耐磨耗性、脱水性に適する構造 脱水の促進

サクションボックス、クーチロールなど

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Papermaking - wire section
Twin-wire machine

Fourdrinier machine

Papermaking – (wet) press section
 A wet web is pressed at high pressure

Felt

Cylinder machine

Web
CylinderQ. What is a merit of
Cylinder machine?

between large rolls to squeeze out excesswater.
 Water transfers to felts that sandwich thewet web.
 Pressing increases
density and wet web
strength.
 The common numberof nips is 3 or 4.
Kodak Historical Collection #003 (1986)

Papermaking – (wet) press section

Papermaking – dryer section
 Steam-heated cylinders dry the paper with canvases.
 Free water evaporates, between fibers first , inside

fibers second, and between fibrils last .
 At less than 9 % moisture content, bonding water

evaporates, forming interfiber bonds.
Paper
Canvas (felt)

Drying cylinder
for felt
DryingcylinderPaper

Canvas (felt)
Vietnam Paper Corporation (2014)

Papermaking – calender section

Papermaking – calender section

 A number of rolls press the passing paper.
 They make the paper surface extra smooth and glossy

with friction, and provide a higher density and more
uniform thickness
プライバシー保護のため、この画像の自動ダウンロードをブロックしました。

Supercalender
Soft nip calender

Biomaterial Science by Toshiharu Enomae

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Papermaking – calendering effect

抄紙－カレンダリングと表面粗さ

Paper gloss, %Linear pressure at nip:Thickness decrease ratio, % Gloss improvement and compression of paper カレンダリングによる表面粗さの低下
温度、ニップ荷重、通紙速度

Basepaper

Coat layer

Number of passed nips

Number of passed nips

 The number of nips is occasionally more than 10.

Q. Why is it as many as 10 although only 3 or 4 for wet press?

Types of chemical bond

抄紙－カレンダリングと光沢 Ionic bond = a chemical bond in which two ions are joined カレンダリングによる光沢度の上昇

together because one has a positive charge and the other anegative charge
 Covalent bond = a chemical bond in which two atoms share
one or more pairs of electrons that hold them together (ca.
500 kJ/mol) Hydrogen bond = a weak connection that is formed between
an atom of hydrogen (= a gas) and an atom of anothersubstance such as oxygen or nitrogen (= a gas) （10～40
kJ/mol）
 Van der Waals forces = the relatively weak attractive forcesthat act on neutral atoms and molecules and that arise
because of the electric polarization induced in each of theparticles by the presence of other particles
 Dipolar bond (coordination bond) Metallic bondInter-fiber bondInter-fiber bondEffect of water on interfiber bond formation

Interfiber approach and hydrogen bondformation due to water evaporation
Cellulose surface

Fiber

H-O-H

L µm

H-O-H

Fiber

H-O-H

Q. Suppose twocrossing flat fibers witha square , length L on aside at the crossing
point. As they dry andthe interfiber distance dcomes to 1 mm, Howmuch contraction stressdevelops between thetwo fibers?



H-O-H



d µm


The attractive force iscalled Campbell force.

Biomaterial Science by Toshiharu Enomae

Cellulose surface

Loose hydrogen bond mediated by water

Firm hydrogen bond with a water monolayer Direct hydrogen bond16

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Inter-fiber bondEvidence of hydrogen bond








Inter-fiber bond
 Effect of cell wall thickness on wet fiber flexibility

When paper mass was measured after allowing tostand in deuterium water (D2O) vapor until
saturation, 0.5 to 2.0 % of hydrogen of all thehydroxyl groups was not replaced with deuterium.
This ratio corresponds to the percentage ofhydrogen bonded hydroxyl groups.
Energy required for tensile breakage was calculated.
19 kJ/mol (equivalent to hydrogen bond energy)
Strength decreased with acetylation of carboxylgroupsCell-OH → Cell-O-C-CH3
OInter-fiber bondForming (Wire section) － Moisture content
HeadboxSlice Effect of fiber flexibility on Relative Bonded Area

Bonding ratio, %Cell wall thickness, µm
4.7 µm
8.8 µmWiresectionFiber flexibility, 1/Nm2

Post-forming－Size press Sizing

Internal sizing- addition to pulp slurry
 External (surface) sizing – application to surface What is surface sizing (size press)?

The treatment for providing water-resistant property
to paper by application of starch solution etc.
 Other than starch, carboxymethyl cellulose, polyvinyl
alcohol, polyacrylamide etc. are applied. Strong
water-repellency is not required.


Size press

Couch roll

Pulp
1%
Moiture99 ％PresssectionCalendersectionDryer section

20 %

40 %

95 %

80 ％

60 ％

5％

Post-forming－Size press Purpose andeffectPicking prevention
in offset printing
 Ink jet printability
to prevent
bleedingAdvantages over internal sizing

100% retained. No deposit on walls of former or froth

Biomaterial Science by Toshiharu Enomae

17

2015_all slides

Post-forming－Size press

Pigment coating

Pigment
BinderWater
Dispersion / Mixture

Pigment coating

Coated paper surface Scanning Electron Micrograph

Blade coater etc.

Pigment coating

Drying and processing – movie

Basepaper
surfaceCoatingsurface

To increase smoothness, brightness,
opacity, and gloss, and control liquid
penetration

Biomaterial Science by Toshiharu Enomae

18

2015_all slides

Paper properties –Fundamental and applied properties

Conditioning and test atmosphere 23 ºC

 Conditioning Structure Surface chemistry Liquid absorption Mechanical properties Optical properties

Conditioning and test atmosphere
Moisture content (%)

 Hysteresis
 Dry paper to half

50 humidity% r.h. (%)
Relative

the equilibrium
moisture content
and back to 50%
RH for testing Moisture content
is affected by
crystallinity

Paper structure – basic properties

50% RH (Relative Humidity)

Paper properties depend on
humidity, but less on temperature
although temperature differenceby more than 10 ºC changes ex.
tensile strength significantly.

Paper structure – basic properties
 Grammage (g/m2)

Mass (g) per square meter at 23 ºC and 50％RH
Grammage（（oven-dry basis）） is based on theconstant mass attained when kept at 105 ºC Thickness (mm)Single sheet thickness, distance between twoparallel planes holding a sheet at 100 kPa
 Bulking thickness, thickness per sheet,calculated from that of 10 superimposed sheets Includes surface roughness (dents)
Paper structure – basic properties Density（grammage/thickness） affected by grammage!?

 Density

Mass per unit volume in g/cm3 calculated fromgrammage divided by thickness

140

Apparent thickness, µm

Q. Which is higher, single sheet thickness or
bulking thickness?

120
100
80
60

Sheets prepared fromsoftwood bleached kraft
pulp beaten moderately

40
20
0
0

20

40

60

80

100

Grammage, g/m2

Biomaterial Science by Toshiharu Enomae

19

2015_all slides

Paper structure – Why is the thickness
different between the two methods?

Paper structure – thickness measurement
 Micrometer
Thickness by Hg buoyancy, µ m

130 Mercurybuoyancy
method

0.5 kgf/cm2-1 min
3.5 kgf/cm2-5 min
7.0 kgf/cm2-20 min

120

Filter paper side

110
100

Laboratory sheet
90
80

Micrometer
thickness

Beaten hardwood kraft
70
70

80

90

100

110

120

Metal plate side

Mercury B
thickness

130

Thickness by micrometer, µm

Process
Beating

Filler(Calciumcarbonate)
Wet press

Calendering

Level
Unbeaten
5000 rev. (PFI mill)
20000 rev. (PFI mill)Unloaded
10 % on dry pulp
30 % on dry pulp
49 kPa for 1 min
343 kPa for 5 min
686 kPa for 10 min
Uncalendered
Linear Pressure 29 kN/m
Linear Pressure 49 kN/m

Density, g/cm3
0.463
0.592
0.722
0.615
0.614
0.606
0.521
0.595
0.647
0.540
0.588
0.624

Paper structure – Factors affecting density

Paper structure – Factors affecting density
 Beating and filler loading
0.8

Density g/cm 3

Paper structure – Processes and density

0.7
0.6
0.5
0.4

Beating rev. (PFI mill）

Calcium carbonate addition

Paper structure-Scanning electron microscope(1) Wet press and calendering
Density, g/cm 3

0.8
0.7
0.6
0.5
0.4

100 µmCopy paper
Wet press

Newspaper

Calendering- linear pressure

Biomaterial Science by Toshiharu Enomae

20

2015_all slides

Paper structure-Scanning electron microscope(2)Paper structure – Smoothness
 Air leak method
 Air flow rate through a gap between paper

surface and smooth metal plate Surface profile (Microscopy)
 Measurement method

Stylus profilometry
Scanning Probe Microscope Confocal Optical Microscope Interferometric Optical Microscope Multi-detector Scanning Electron Microscope Expression of surface roughness

100 µmJapanese paper

Tissue paper

Paper structure – Smoothness

Paper structure – Smoothness

 Air leak method

 Air leak method Air flow rate through a gap between

paper surface and smooth metal platePrint surf roughness (µm)
Bekk smoothness, Oken smoothness (s) Surface profile (Microscopy)

Parker Print-Surf (a slab)

 Surface shape measured using

Measuring headprofilometry such as stylus profilometry,
confocal optical microscope.
 Several ways of expressing surface
roughnessPaper
structure
紙の構造-平滑度– Smoothness
Oken type (circular tubes)

紙の構造-平滑度

Theory of air leak method

Paper
Backing rubber

プリントサーフ粗さのモデル図
w:金属面の幅

Hagen-Poiseuille flowπ∆P r 4Q=
8µ l
Q: volumetric flow rate
∆P: pressure differenceµ: dynamic viscosity
r: radius of tube
l: length of tube

w

y

x
x
rθ

Air
flow

z

Q: flow rate inz direction

Biomaterial Science by Toshiharu Enomae

G3
lFig. 3 Schematic diagram of a channel for air leak in
the PPS model.

21

2015_all slides

Paper structure– Smoothness
紙の構造-表面形状測定

紙の構造-平滑度
プリントサーフ粗さと王研式平滑度の比較

プリントサーフ粗さ(µm)

 12µlQ  13
G3 = 
 w∆P 



8µV l
8µV
L0
=
4
π ∆Pr
π (Pc − P ) R0 4



TB =

G3： 平均間隙〔距離〕

TB ： 王研式平滑度〔時間〕µ ： 空気の粘度µ ：←l ：金属面の長さ

l ： ポア長さ, L0 ： 連結管の長さ

Q：空気の体積速度

V ：空気の体積 = Q ×TB

w：金属面の幅

r ：ポア半径, R0 ： 連結管の長さ∆P：圧力差∆P ：←, PC-P ： 定圧室と測圧室の圧力差

MethodCenterline average roughness(arithmetic average)Ra

Gurley tester

A:642 mm2
Airtester∆pOken

y
dy

RMS =

1 l
2
D ( y ) dy
∫
0
l

l

Paper structure –Smoothness of coated paper

V
P=
1000 × A ∆p t

450
400
350
300
250
200
150
100
50
0

0.5

After calendering
Basepaper
Before calendering

0t: permeation = Air resistance(Gurley)time (s)

5

10

15

20

Latex content, pph

Paper structure - Formation

Paper structure –Air permeance of coated paper
Air permeance, µm/Pa･s

D(y)

D(y)

Universal
air permeance

V: 100 mL

1 l
D( y )dyl ∫0Root mean squared roughness

Air permeanceP [mm/(Pa･s)]



=

z

Paper structure – Air permeanceSurface profile can be measured in 2D or 3D.
Stylus, light beam, electron beam, or probe王研式(ベック）平滑度(秒)Oken smoothness, sFormation[

0.4

Before calendering

0.3
After calendering

0.2
0.1
0
0

5

10

15

Latex content, pph

Biomaterial Science by Toshiharu Enomae

20] Unevenness sensed visually when
white light is transmitted through paper – STD or
CV of optical density
Transmitted light I 0  I1 I2 …
log Mass
B1 B2 …
 In 
[]
Distribution of
local mass Bn –STD or CV ofPaper I0 I0
local mass
Irradiating light
STD=Standard deviation, CV= coefficient of variation22

2015_all slides

Paper structure - Formation
Time until dehydration (s)10Transmitted lightimages of softwood
pulp sheets Formation becomes
(F)
worse
by cationicpolymer addition
and increased time
until dehydration
 Cationic polymers
increases fiber
retention.

紙の構造-地合（じあい）120 地合の評価は標準偏差や変動係数でよいのか。

Cationic polymer
P:Added
N:Nonadded

サンプル
グレーレベル

HN10

相関係数
r

の平均

45.3

45.6

34.2

32.2

〃

の標準偏差

2.1

2.3

1.7

3.0

0.36

光学濃度

の標準偏差

0.020 0.022 0.022 0.040

0.64

光学濃度2

の標準偏差

HN120

0.030 0.033 0.038 0.072

0.79(光学濃度2の標準偏差)/坪量,
10-3 m2/g

47

53

52

95

0.86

主観評価値
（小さいほど地合良）

0.0

3.6

1.4

6.4

ケンドールの相関係数rは、この4種以外にも針葉樹パルプのデー
タを含む主観評価値と各パラメータとの間の相関を示す。

HP120

HP10

Surface chemistry - Contact angle

Interaction- between paper and water (liquid)

Wetting Contact angle
 Surface energy Sizing degree
 Liquid penetration SwellingContact angle (θ)
 The angle made by the solid and liquid surfaces

when a liquid droplet is placed on a solid
surface.
 When 0º< θ < 90º, “wetted” and when θ>90º
γL“unwetted”.

Young equationθ When the contact angle

is constant, horizontal
components of forces
are balanced.

γsγiγi － γs ＋ γL cos θ ＝0

Surface chemistry - Contact angle

Surface chemistry - Contact angle

Contact angle on a rough solid surface Supposed that the area including

microscopic structure is r times larger
than the apparent one, Wenzel’s contact angleγLcosθ w = r cosθθwγi

cos θ w = r cos θ

Wenzel’s equation

 On a rough surface,θγswhen θw ＜ θ at θ ＜90º, easily-wetted
surfaces become
more easily-wetted.
But, ＞ θ at θ ＞ 90º,hardly-wetted
surfaces become
more hardly-wetted.

180

Apparent見かけの接触角θw
contact angle θw



HN10 HN120 HP10 HP120

r=1 の場合

150

r=1.2の場合
r=2 の場合

120

Hardly-wetted

90

60

Easily-wetted

30

0
0

30

60

90

120

150

180

真の接触角θ
Real contact
angle θBiomaterial Science by Toshiharu Enomae

23

2015_all slides

Contact angle of paper - Beating effect140

Wet-press: 90 g/m2, 0.70 MPa

120
110
100

5000 rev beating
10000 rev beating
20000 rev beating

90

200

400

 Surfacessmoothed bybeating
became easilywetted.

20
15
10
5
0

80
0

Hardwood kraft pulp sheet

Oken smoothness, sContact angle, °130

Beating and smoothness

600

20000 Rev
10000 Rev
5000 Rev

Contact time, s

Grammage and wet press pressure

Surface chemistry - Contact angle

On composite surfaces

 The effective contact angle θC is dependent on

the area ratio of each component.


Cassie's law
 is stated ascosθ C = Q1 cosθ1 + Q2 cos θ 2, where θ1 is the contact
angle for component 1 witharea fraction Q1 and θ2 is theθcontact angle for component
2 with areal fraction Q2 (Q1+ Q2 = 1).
Component 1 Component 2

Surface chemistry - Contact angle
Q. What is the contact angle θc of sized paper?
 Sizing agent need not cover the whole surfaceof fibers for repelling water. If a sizing agent
covers 5% of the whole surface, what is thecontact angle θ ?
 Assume that θ is 0˚ for unsized fibers and 120˚
for the covering size.
θc(G) × cos 0º +
 cosθc = 0.95
(H) × cos 120º
0.05
Paper
cosθc = 0.95 –(I)0.025 = 0.925(J)θc = 22.3º

Size

Surface chemistry - Contact angle

Surface chemistry - Contact angle

Q. What is the contact angle θc of sized paper?

Q2. What is the contact angle θc of sized paper?
 Half the volume of paper is air. If 50% of
paper surface is air, what is the θc ?
 Assume that θc of a true surface of sized
paper is 22.3˚ and θ of air is 180˚.
(K)(K)
 cosθc = 0.5×cos
22.3º + 0.5×cos
180º(K)(L) + (K)cosθc = 0.5×0.925
0.5× (M)1θc(N)= 0.155

 Sizing agent need not cover the whole surfaceof fibers for repelling water. If a sizing agent
covers 5% of the whole surface, what is thecontact angle θ ?
 Assume that θ is 0˚ for unsized fibers and 120˚
for the covering size.
θc cosθc = 0.95 × cos 0º +0.05 × cos 120ºPapercosθc = 0.95 – 0.025 = 0.925

θc = 22.3º

SizeBiomaterial Science by Toshiharu Enomae(O) ºθc = 92.1

Paper
Size

24

2015_all slides

Surface chemistry - Contact angle

Surface chemistry - Contact angle
Q2. What is the contact angle θc of sized paper?
 Half the volume of paper is air. If 50% of
paper surface is air, what is the θc ?
 Assume that θc of a true surface of sized
paper is 22.3˚ and θ of air is 180˚.
 cosθc = 0.5×cos 22.3º + 0.5×cos 180ºcosθc = 0.5×0.925 + 0.5× -1
θc= -0.538θc = 122.5ºParchment“wood-containing” means “made from mechanical pulp”

紙の両面から吸水させたとき、水が中央で接触するまでの時間（秒）をステキヒトサイズ度とする。
5 cm四方の紙を船の形に折るチオシアン酸アンモニウム水溶液に浮かべ、塩化第二鉄水溶液を滴下し、計時を開始
赤色斑点が3つ現れるまでの時間（秒）を測定



紙の接触角
接触角は変化する。
液体の吸収が同時に起

こる。


濡れ時間
右図のT
液体の浸透が始まるま

での時間でオイルには存在しない。
接触角が変化してθ<90ºとなるまでの時間

Liquid absorption theory - Capillary modelForce developing arounda meniscus of a liquid ina capillary (pipe)
Steady flow in a pipe

πPr 4
Q=
8ηl
l: Capillary lengthr: Capillary radius
η: Liquid viscosity
Q: Volumetric flow rate

γcosθ
θ

F=2πrγcosθ
Fw

Contact time, s
クラフト板紙でのブリストープロット。オイ
ルでは濡れ時間が存在しない。

H-P equation

2γ cos θrdVdlQ== π(Q)
r2
dt
dt
Substitute

πPr 4
Q=
8ηl

S=πr2
θ

P=

r

Biomaterial Science by Toshiharu Enomae

T

Q. Substitute the relation represented in the figure into
the H-P equation and develop the Lucas-Washburn equation.

2πr(Hagen-Poiseulle equation)

Ka
Vr

Liquid absorption theory - Capillary model

P=F/S=2γcosθ/rPγ

Transferred liquid volume, ml/m2

Surface chemistry - Wetting

紙のサイズ度-ステキヒトサイズ度Wood-containing paper

Paper
Size



Comparison in Water absorption



dl

dt

2dl
dV = πr(P)rLucas-Washburn equationl=rγ cos θ ⋅ t2η

25

2015_all slides

液体の浸透理論-Lucas-Washburnの式



液体浸透の基本式
塗工紙へのオイル(インキ)の浸透で成り立つl=
V ∝l =

Rγ cosθ ⋅ t
2η
R cosθ
2

l: 浸透深さ
R: 毛管半径γ: 表面張力θ: 接触角η: 液体の粘度
t: 時間

γt
η

Water absorption rate – How to measure



v
b

w

Vr Roughness index
T Contact time
Tw Wetting delay
Ka Absorption coeff.

 Tr vol per area Vt= V

Liquid volume V
Slit widthw
Trace length L

wL

Vr Roughness index
T Contact time
Tw Wetting delay
Ka Absorption coeff.
For oil, Tw = 0.
Then,

Vt = Vr + K a T

Vt=V/(wL)Vw
L

Vt = Vr +(Q)
Ka T

Oil A

Vt

Oil B

Water
Ka
Tw

Vr

Contact time, s

T

液体の浸透-塗工紙への有機液体の吸収

Oil B

Water
Ka

Bristow’s plot of kraft paper

v
b

Oil A

Vt

Vr

For oil, Tw = 0.
Then,

Transferred liquid volume, ml/m2

For water,

Transferred liquid volume, ml/m2

Liquid volume
Slit width
Trace length

Bristow’s plot of kraft paper

Water absorption rate – Water and oil
Vt = Vr + K a T − Tw

For water,

Vt = Vr + K a T − Tw

V

Scan speed
Slid width

t=b/v

Water absorption rate – Water and oil

Calculate transferred volume per unit area Vt

 Contact time t = b/v

 Contact time Transfer Volv

Vt

15 mm (w)

Scan speed
Slid width

液体・時間

L

1 mm (b)
Paper
moves

V

V: 浸透体積材料の構造と濡れ特性Bristow’s apparatus

A liquid supply head filled witha liquid of volume V scans
paper at various speeds v.

Transferred liquid volume, ml/m2

Water absorption rate - How to measureTwo-Dichrolobenzene
Toluenen-Dodecane
LigroinAnilineParaffin oil

Contact time, ms (root scale)Contact time, sBiomaterial Science by Toshiharu Enomae

T

Linseed oil

γt dyne ⋅ m sec,
ηcm ⋅ cP

有機液体の吸収ではLucas-Washuburnの式が成り立つ。非塗工紙についても含水率によって接触角が変わる可能性もあるが、概ね成り立つ。

26

2015_all slides

Water absorption rate - How to measure

液体の浸透-水の吸収-弱サイズ非塗工紙
Transferred liquid volume, ml/m2

Wire side

Automatic Scanning Absorptometer（Spiral-scan Bristow’s apparatus）

To meniscus
detector

 Scanning speed changes stepwise during
measurement

Wire side

Water supply
head

Felt side
Felt side

1 mm
5 mm
Contact time, ms (root scale)Contact time, ms (linear scale)

Infrared sensor
Glass capillary

水の吸収ではLucas-Washburnの式が成り立たない。繊維（上質紙の場合セルロース）中への水分子の拡散で説明される。

Meniscus
Step motor

ASA

Water absorption rate of ink jet paper -ASA

インクジェット紙の吸水挙動
2Side of ink receptive layer

20

Transferred water volume, mL/mVolume of transferred water, ml/m 2

25

15
10
Side of NON-ink receptive layer

5035
Photo quality IJ (A)30

Photo quality IJ (B)25High gloss type IJ (C)20High gloss type IJ (D)15Medium grade IJ (E)Medium grade IJ (F)10

Noncoat Copier

5
Noncoat Offset

0

0

5

10

15

20

0

5

Square root of contact time, (ms)1/2

10

15

20

25

30

Square root of contact time, (ms)0.5

Water absorption rate of ink jet paper -ASA

Mechanical properties –Tensile strength
Load-elongation curve

40



F

No.2

 100 mm in span

No.3

30

20
・インキが転移しなかった部分のデー
タ点、明らかに誤ったデータ点を省略
してプロットした図・No.1と2は、ほぼ同じ傾向のインキ

10

0
0

Method 15 mm in width

5

10

Square root of contact time, (ms)1/2

Biomaterial Science by Toshiharu Enomae15

 10 mm/min elong speed

Limit ofelasticity

Load, N

Volume of INK transferred, mL/m2

No.1



∆F




: 


∆Li
Elongation, mm

Tensile index Iࡵ ൌ εT ൌ

∆L



:





Strain at break εT∆Modulus of elasticity E*
 E*ൌ

∆
: 
∆

27

2015_all slides

Mechanical properties –Tensile strength

Anisotropy–Tensile strength
12

Plastic region
 Extension of curl

Load, N

Compressive
force

Elastic region

Load, kgf

compression
 Breakage of interfiber bonds
 Breakage of fibers

Elongation, mm

Unbeaten kraft paper (89.4 g/m2)
Copy paper (64.4 g/m2)

10 Extension of micro-

Unbeaten kraft

6

Copy paper

CD

4
2

Fiber

0

 Elastic elongation of fibers

0 Elastic elongation of fiber

network

1

2

Microcompression

During drying

3

 (Bending) stiffness

MD

Light-weight coated paper
Newsprint paper

CD

S=Mr

7

8

moment

S=EI
E is Young’s modulus
I is area moment of

M is bending

6
4

6

S represents the degree to which

paper resists bending

10
8

5

Mechanical properties – Stiffness

12

Light-weight coated paper(64.9 g/m2)
Newsprint paper(46.4 g/m2)

4

Elongation, %Anisotropy–Tensile strength

Load, kgf

MD

8

r (m)

inertiar is radius ofcurvature

2
0
0

1

2

3

4

5

6

7

M

8

M (mN⋅m)

Elongation, %Q. Why does light-weight coated paper elongate greatly?

Mechanical properties – StiffnessTaber Stiffness

Mechanical properties – Stiffness15˚

クラークこわさ 試験片を挟んで上に向けて支持する。つかみの回転によりある角度で反対側に反り返る。この角度の左右両側での差が90度となるよう、つかみから試験片を張り出す。その張り出し長さL（cm）の3乗の100分の1をクラークこわさとする。

 Bending moment

when a test piece
38mm wide is bent
to 15˚ and load
length 50 mm
 The unit is mN⋅m

ここで、坪量Wはkg/m2、厚さTはm、ヤング率EはPaを単位とする。
3
3
3

L
L
EI
ET
∝
=
=
100 203 bW 12W
Taber tester

Biomaterial Science by Toshiharu Enomae

クラーク（低坪量用）

28

2015_all slides

紙の強度- 含水率の影響

Mechanical properties – Folding endurance破裂 Folding endurance85

 logarithm number of

1kgf

相対湿度
相対湿度, %

double folds at 120˚on both sides thatare required tomake a test piecebreak Longer fibers
tend to show
120˚
higher values.

120˚

Burst
strength75

Tensilestrength65

引張Folding endurance

45

耐折

35

Stretch

引張破
断伸び

15
50 40 30 20 10

NBKP

50

破断伸び

NBKP

3

密度

40

比引張強さ

LBKP

2.5

耐折強さ

35

増加,
増加 パーセント

紙の強度 繊維組成、叩解、添加物の影響

LBKP

45

10 20 30 40 50 60 70

0減少,
減少 パーセント

紙の強度 繊維組成、叩解、添加物の影響

Tear 引裂strength

55

25
MIT tester

水分Moisturecontent230比引張強さ(Nm/g),
破断伸び(%×10)

25

3

密度(g/cm ),耐折強さ(回)

20
15
10

1.5
1
0.5

5000R叩解

3000R叩解

サイズ・填料無添加

サイズ（+助剤）

サイズ・填料無添加

サイズ・填料無添加

サイズ（+助剤）

5000R叩解

サイズ（+助剤）

3000R叩解

サイズ・填料無添加

サイズ（+助剤）

サイズ・填料無添加

3000R叩解

サイズ（+助剤）

サイズ・填料無添加

サイズ・填料無添加

5000R叩解

サイズ（+助剤）

3000R叩解

サイズ（+助剤）

サイズ・填料0
サイズ（+助剤）

0

無添加

5

5000R叩解

力学特性-摩擦係数
WeightPaper

Frictional force

Sled

Load cell

Prospective future with
Paper devices andEco-friendly materials

Stage

Paper on sled: 50 mm (L)×35 mm (W)Paper on stage: 40 mm (W)Pressure:
1.98 kPa (353 g / 1750 mm2 )Slide length:
25 mm
Slide speed:
0.2 mm/s

Biomaterial Science by Toshiharu Enomae

Toshiharu Enomae
Professor
Faculty of Life and Environmental Sciences
University of Tsukuba , JAPAN29

2015_all slides

 Paper device（Paper in future）• Paper electronics• Paper–based medical check-up sensor• Energy supply device

Development of Paper-based medical
check-up sensor and technology ofliquid transport in a micro-channel• Paper-based bioassay system

Kento Maejima
Yinchao Xu
Toshiharu Enomae Paper cultural heritage（Paper in past）• Conservation Science Fundamental papermaking technology（Paper at present）• Paper coating, paper physics and chemistry, etc.
Yinchao Xu

Paper substrate
Doctor in hospital• Capillary force due to porous structure

Data

Diagnosis
Patient at home

• Liquid transport
designed channel

・Fewer patients in hospital for fewer days
→ Appropriate medical service by hospitalLab-on-paper as a medical check-up sensor

Affordable and simple device is required

Microchannel Fabrication
Advantage of paper and improvement• Cheap, disposable, portable, and flexible• Cotton linter pulp→ almost no impurities• Porous → micro-channel to transport liquid• Smaller pore size → Less ink bleeding
Beating,
revolutions-PFI millDensity,
g/cm3

1

10000

0.568

2

20000

0.622

3

30000

0.641

#

IJ printing

UV irradiation

Paper
Top

Top

Back

Back

Perspective

Top
Back

3 mm

Citterio, D. et al., Proc. MicroTAS 2011, 2099-2101

Microchannel was successfully fabricatedBiomaterial Science by Toshiharu Enomae

30

2015_all slides

Fabrication Processes of electrodes

PDA application
Mussel’s adhesive protein

Electrodes printed with PEDOT:PSS

・Strong adhesion, even to Teflon®!
・Composed of DOPA (amino acid)
HO

COOH

Prepared paper
HO

Micro-channel printed
with UV-curable ink

Teflon®

NH2

Lee, H. et al., Science 318, 426 (2007)

DOPA

Poly(dopamine) (PDA)

BMP printed
Enzyme (Glucose oxidase) printed

・Mussel’s protein mimic polymer
・Facile fabrication process
HO

EnzymeBMP (binder&mediator)HO

PEDOT:PSS (electrode)NH2

200 nmHong, S., Adv. Funct. Mater. 2012, Early View

Lab-on-Paper was successfully fabricated

4 mm

Sample solution• 0.5 M KCl• 2 mM K3[Fe(CN)6]• 15 U/mL HRP• Glucose Conc.
(0-4.16 mM)
Current (t=10 s) [mA]

NaOH solution

Dopamine

Potentiostat

Dispense(4 μL)

Micro-channel
printed

30 mm

Ink jet printer1.2

Dimatix DMP-2831
Fuji Film, JAPANy = 0.160 x + 0.203
R² = 0.979

0.9
0.6

n=3

0.3

Glucose + O2 
Gluconic acid + H+ + e-

Ink
• Styrene-acrylate copolymer, CP-900, Harima Chemical, JAPAN• Neutral red (dye staff)

Glucose concentration
quantified successfully

0
0
1
2
3
4
5
Glucose Concentration [mmol]

Laboratory of Paper Devices and Eco-friendly Materials
Prof. Toshiharu Enomae, University of Tsukuba

Effect of beating

9

10000 Rev

0.1
0.08 2000 Rev

Effect of calendering
Conversion of vibrationenergy of paper toelectric energy

875000 Rev

6

Volume (μL)

Volume/ Grammage (μL/g/m2)

0.12

0.06

5
4
3

0.04

Uncalendered
0.5 MPa
1 MPa
3 MPa

2
0.02
1
0

0
0

200

400

600

800

1000

Time (s)Lucas-Washburn’sequation: V ∝ rp

Beatingrp

Calendering rp

Moving-electrodeMoving-electrode

Electrode (Copper)
0

50

100
Time (s)rpWatertransport rp

Biomaterial Science by Toshiharu Enomae

150

200

Paper

Irreversible
Reversible

Electret (Teflon)
Electrode (Copper)～

Electretii
R

Static-electrodeVibration31

2015_all slides

Paper-made Electric Power Generator

Application to:
Voice-activated posters

Oct 31, 2015

IPPC2015 @ Tokyo

Paper electronics and sensors
Inorganic ELloaded paper
Alternating
electric field
Capacitor
Solar cell
Drives other paper
electronics

Illuminating
paper

Flexible
illumination

Solution

Paper-based bioassay
Paper-based water quality sensor

Cu2+

Productmanagement
IC tag （RFID）
Record oftransportation

Paper-based power generator

Paper

Cu2+ sensor Electrodes
Detection of toxic heavy metal
ions and radioactive substances

IPPC2015 @ Tokyo
Oct 31, 2015

Oct 31, 2015

Self-powered paper device

1- 1000 µW/cm2
Gen. eff. 2-5%

50- 100,000 µW/cm2
Gen. eff. 25-35%

Light

IPPC2015 @ Tokyo

Heat

Energy harvested from

Inorganic ELloaded paper
Alternating
electric field

Noise, voice, soundVibration of paper

Illuminating
paper

Flexible
illumination

Solution
Cu2+

Vibration
50- 1000µW/cm2Gen. eff.
20-70%

Oct 31, 2015

0.1- 100µW/cm2On-site electronic
power supply

Radio wave
IPPC2015 @ Tokyo

Paper

Cu2+ sensor Electrodes
Detection of toxic heavy metal
ions and radioactive substances
IPPC2015 @ Tokyo

Oct 31, 2015

Source :www.fujitsu.com

Biomaterial Science by Toshiharu Enomae

32

2015_all slides

Laboratory of Paper Devices and Eco-friendly Materials
Prof. Toshiharu Enomae, University of Tsukuba

Conversion of vibrationenergy of paper toelectric energy

Principle of electrostatic induction
Static electrode

Static electrode

Electret

ElectretR

R

Moving electrodeMoving-electrodeMoving-electrode

Electrode (Copper)
Paper

Electret (Teflon)～

Electretiii

iMoving electrodeR

Static-electrode

Electrode (Copper)
Vibration

Oct 31, 2015

IPPC2015 @ Tokyo

Experimental

Electric power generation by vibration

1. Fabrication of electret-induced
power generator (tapping type)
2. Measurement of displacementof paper by vibration
3. Fabrication of electret-induced
power generator (sliding type)Tapping makes electricity
Oct 31, 2015

IPPC2015 @ Tokyo

Experimental
1. Fabrication of electret-induced
power generator (tapping type)

Oct 31, 2015

IPPC2015 @ Tokyo

Electret-induced power generator (tapping type)
Materials
Paper board :736g/m2
Paper
Teflon: 0.5 mm thickDistance: 2 mm

Cu electrode
Electret (Teflon sheet)～
Cu electrodeVibration

2. Measurement of displacementof paper by vibration

Vibration generator

Vibration condition
Frequency: 10-60 Hz
Amplitude: 1 mm
Measurement condition
Sampling rate: 200 Hz

3. Fabrication of electret-induced
power generator (sliding type)
Oct 31, 2015

IPPC2015 @ Tokyo

Biomaterial Science by Toshiharu Enomae

Oct 31, 2015

IPPC2015 @ Tokyo

33

2015_all slides

Electret-induced power generator (tapping type)

Results – generated voltage
3.5

3.5

10 Hz forced2.5vibration

Cu electrode
Paper

Generated voltage (V)Vibration

Electret
Cu electrodeVibration generator

-0.7

-0.5

-0.3

1.5

1.5

0.5

0.5

-0.5
-0.1

0.1

0.3 -0.7

-0.5

-0.3

Generated voltage (V)Oscilloscope-0.3

Generated voltage (V)2.5

20 Hz forced vibration

30 Hz forced vibration

2.0

-3.5

3.5

3.5

2.5

2.5

1.5

1.5
0.5

-0.5
-0.1

0.1

0.3 -0.7

-0.5

50

100

150

200

250
0

Frequency (Hz)41Hz;
1.74 V

100

150

200

250
0

50

Frequency (Hz)

2.5
2.0

50

8

8

20 Hz forced vibration

30 Hz forced vibration

4

4

2

2

0
-0.1
-2

0
-0.1
-2

6

0.1

0.3 -0.7

-0.5

-0.3

40 Hz forced vibration

200

250

Frequency (Hz)47Hz;
2.36 V

46 Hz forced vibration

-0.5

-0.3

51 Hz; 50 Hz forced vibration
1.56 V

51Hz;
0.68 V82Hz;
0.19 V

-0.3

0
-0.1
-2

-6
-8

8

8

46 Hz forced vibration

50 Hz forced vibration

6

6

4

4

4

2
0.1

0.3 -0.7

-0.5

-0.3

0
-0.1
-2

0.3

Time (s)

6

0
-0.1
-2

0.1

-4

-8

2
0
0.3 -0.7

0.1

-0.5

-0.3

-0.1

0.1

0.3

-2

-4

-4

-4

-6

-6

-6

-8

-8

-8

Time (s)Time (s)Time (s)6

Results –generated voltage

4

51Hz;
0.68 V 94Hz;
0.26 V

Voltage (V)

0.5

-0.5

8

Background

1.5
1.0

0.3 -0.7

-6

2
-0.7

2
0.1

Time (s)40 Hz forced vibration

150

6

-4

-4

8

100

0.3

-2.5

-8

0

0.1

-3.5
Time (s)IPPC2015 @ Tokyo

-6

20Hz;
0.09 V

-0.5
-0.1
-1.5

Time (s)51Hz;
0.77 V
31Hz;
0.38V

51Hz;
0.78 V51Hz;
1.0
0.80 V10Hz;
0.5 0.09 V
0.0

Generated voltage (V)

-0.3

4

-0.3

0.3

Time (s)

8

-0.5

0.1

46 Hz forced vibration

10 Hz forced vibration

-0.7

-0.5
-0.1

-2.5

Time (s)Time (s)1.5

Generated voltage (V)Generated voltage (V)

10 Hz forced vibration

-0.3

-3.5

6

Results – generated voltage – FFT

-0.5

-2.5

-1.5

Oct 31, 2015

0.3 -0.7

-3.5

-2.5

IPPC2015 @ Tokyo

0.1

-2.5

-3.5
Oct 31, 2015

0.5

-0.5
-0.1

-1.5

0.5
-0.5

1.5

-1.5

40 Hz forced vibration-0.7

30 Hz forced2.5vibration-1.5

Time (s)Function generator

3.5

20 Hz forced2.5vibration

2
-0.7

-0.5

-0.3

0
-0.1
-2

0.1

0.3

-4

0.0
0
50
Oct 31, 2015

100

150

200

Frequency (Hz)

250
0

50
100
150
IPPC2015@ TokyoFrequency
(Hz)

200

250
0

50

100

150

Frequency (Hz)

200

250

Oct 31, 2015

-6
-8

IPPC2015 @ Tokyo

Time (s)Electret-induced power generator (tapping type)

Results – generated voltage – FFT
4

Voltage amplitude (V)

2 mm gap

10 Hz of forced vibration
20 Hz of forced vibration
30 Hz of forced vibration
40 Hz of forced vibration
46 Hz of forced vibration
50 Hz of forced vibration

3

2

Vibration
Vibration generator

Cu electrode
Paper

Electret
Cu electrode

Forced vibration frequency
1

Function generator00
Oct 31, 2015

50

100

150

200

Frequency(Hz)
Generated voltage
frequency(Hz)
IPPC2015 @ Tokyo

Biomaterial Science by Toshiharu Enomae

Oscilloscope250
Oct 31, 2015

IPPC2015 @ Tokyo34

2015_all slides

Electret-induced power generator (tapping type)Vibration

Generated power lighted LED

Cu electrode
Paper

Vibration generator

Electret
Cu electrode

Function generatorLED

Oct 31, 2015

IPPC2015 @ Tokyo

Electret-induced power generator (tapping type)Vibration

Oct 31, 2015

Comparison between electret materials

Cu electrode
Paper

Vibration generator

Electret
Cu electrode

IPPC2015 @ Tokyo

Vibration

Cu electrode
Paper

Electret
Cu electrodeVibration generator

Resistance (10 k – 10 MΩ)

Function generator

Function generator
LED
Power meterOct 31, 2015

IPPC2015 @ Tokyo

Comparison between electret materials

Oct 31, 2015

Comparison between electret materials

Teflon (Crystallized perfluoropolymer)
Paper

Teflon (Crystallized perfluoropolymer)

Electret
Cu electrode

Cytop (Amorphous perfluoropolymer)

Cytop (Amorphous perfluoropolymer)

F2C
CF2
FC CF
O
CF2
CF2
n

F 2C
CF2
FC CF
O
CF2
CF2
n

COOH
Oct 31, 2015

IPPC2015 @ Tokyo

IPPC2015 @ Tokyo

Biomaterial Science by Toshiharu Enomae

COOH
Oct 31, 2015

IPPC2015 @ Tokyo35

2015_all slides

Comparison between electret materials

Results – generated voltage and power
1210Discharge gun

7
6
5

Power(μW)

ElectretPaper

8

Teflon
PTFE
Cytop
APFP
PTFE
Teflon
APFP
Cytop

8
4
6
3
4

2

2

Corona discharge

Voltage(V)14Corona discharge of
Teflon and Cytop films

10
1.E+0410

1.E+05100
1.E+0710

1.E+06
10

Resistance(Ω)
IPPC2015 @ Tokyo

Oct 31, 2015

IPPC2015 @ Tokyo

Results – generated voltage and power

1. Fabrication of electret-induced
power generator (tapping type)

Maximum ElectricThickness (μm)
Power (μW)

Teflon

11.8

514

Cytop

12.1

10

2. Measurement of displacementof paper by vibration
3. Fabrication of electret-induced
power generator (sliding type)

Amorphous perfluoropolymer (Cytop)→ High power output→ Thin film formation→ Strong adhesion to paper
Oct 31, 2015

IPPC2015 @ Tokyo

Oct 31, 2015

Resonant vibration of paper

Profilometer

Wave
function
generator

Measurement condition
Vibration freq: 1-65 Hz
Sampling rate: 200 Hz

Displacement (mm)Fixed point

Results - resonant vibration of paper
1.3

10 Hz forced vibration

0.25

1.1
0.9
0.7
0.5
100

200
300
Time (ms)400

Biomaterial Science by Toshiharu Enomae

0.10
0.05
0

1.4

1.0
0.8

Oct 31, 2015

100

200
300
Time (ms)

400

20

40
60
Frequency (Hz)

80

100

80

100

0.25

40 Hz forced vibration
1.2

0
IPPC2015 @ Tokyo

0.15

500

0.6
Oct 31, 201510.2 Hz;0.24 mm

0.20

0.00
0

Displacement (mm)Paper
Vibrator

Paper sample
Grammage: 80 g/m2
Dimension: A4 format(210  297 mm2)
Direction: MD & CD

IPPC2015 @ Tokyo

Displacement (mm)Electret material

Experimental

Displacement (mm)Oct 31, 2015

0.20
0.15
39.8 Hz;0.04 mm

0.10
0.05
0.00

500
IPPC2015 @ Tokyo

0

20

40
60
Frequency (Hz)36

2015_all slides

Electret-induced power generator (sliding type)

Experimental
1. Fabrication of electret-induced
power generator (tapping type)Moving part

2. Measurement of displacementof paper by vibration

Fixed part

3. Fabrication of electret-induced
power generator (sliding type)

Electrodes
Shape: comb
Measurement condition
A few strokes by handOct 31, 2015

IPPC2015 @ Tokyo

Oct 31, 2015

Electret-induced power generator (sliding type)

Electret-induced power generator (sliding type)Moving part

Fixed part

IPPC2015 @ Tokyo

Corrugated board (as supporting material)
Paper (150 g/m2)
Teflon ( 0.2 mm thick)
Paper ( 150 g/m2)
Corrugated board

Oscilloscope

Generated voltage (V)

1.2
0.8

One stroke

0.4
0.0
-0.4

-0.8

-0.6

-0.4

-0.2

0.0

0.2

0.4

0.6

0.8

-0.8
-1.2

Oct 31, 2015

IPPC2015 @ Tokyo

Oct 31, 2015

Results – generated voltage by sliding

0
-0.8

-0.4

0.0

0.4

0.8

-5

Generated voltage (V)Generated voltage (V)

5

1.0
0.8
0.6
0.4
0.2
0.0

-10

0

50

0

50

Time (s)
10
5
0
-0.8

-0.4

0.0
-5
-10

Oct 31, 2015

100

150

200

250

100

150

200

250

Frequency (Hz)1.2Time (s)0.4

0.8Generated voltage (V)Generated voltage (V)1 mm gap

Time (s)Conclusion

1.2

10

3 mm gap

IPPC2015 @ Tokyo

1.0
0.8
0.6

Electric energy was successfully
generated by electrostatic induction
using a paper and electret espeicallyfrom Cytop. This paper-based power
generator achieved up to 12.1 μW at
10 μm in thickness.

0.4
0.2
0.0

IPPC2015 @ Tokyo

Frequency (Hz)Biomaterial Science by Toshiharu Enomae

Oct 31, 2015

IPPC2015 @ Tokyo37

2015_all slides

Paper-based sensors to detect
Cu2+ in drinking water

Paper-based power generator

Dye

Paper-based water quality sensor

Dye + 2 ppm Cu2+
Filter paperwith quinone
derivative dye

Paper-based bioassay
Cu2+ 2 ppm （maximum amount allowed by WHO）
Light scattering by paper enhances color difference.
Oct 31, 2015

IPPC2015 @ Tokyo

Paper-based power generator
Fluorescence Intensity (a.u.)

Dye

Dye + 2 ppm Cu2+

3000

Paper-based water quality sensor

2500
2000
1500
1000
500
0
500

520

540

560

580

600

Blank
5 μM
10 μM
15 μM
20 μM
25 μM
30 μM
35 μM
40 μM
45 μM
50 μM

Wavelength (nm)Paper-based bioassay

Oct 31, 2015

IPPC2015 @ Tokyo

Concept
Bacterial culture system using paper
substrate and ink jet printing

Human-operated system

Automatic system

Bacterial cells are dispensed
on media in paper containerusing inkjet printer

Conditions of bacterial
growth on paper can beobserved by microscope

Tithimanan Srimongkon
Toshiharu Enomae

Oct 31, 2015

Biomaterial Science by Toshiharu Enomae

IPPC2015 @ Tokyo38

2015_all slides

48 hours after printing

Agar sheet medium

Agar sheet medium

Dot of E. coli colony

Preparation of paper substrates

Multi cartridge system printerCalcium chloride

Soaking paper in polystyrene(PS) solution for 1 hour anddryingToluene (with blue dyedissolved) printed byusing inkjet printerHydrophilic/hydrophobic
paper

Test of hydrophobicity
K. Abe, and et., Anal. Chem. 80 (2008): 6928-6934
Oct 31, 2015

Hydrogel culture medium ofcalcium alginate
Sodium Alginate

Na

Magenta = Yeast extract
Yellow = Bacto trypton

O

Na
Na

Cyan = CaCl2 aq

Na

Na

Na

Ca

Calcium Alginate

O

O

Ca

O

O
O
HO

Oct 31, 2015

O

-O

Ca2+

O

Ca
Ca

HO

HO
O-

Ca

Ca

O

O

Na

Black = sodium alginate

HO
O

HO

Na

CaCl2
Solution

O-

Na

HO

Amount of solution = %CMYK

Sodium alginate

IPPC2015 @ Tokyo

HO

IPPC2015 @ TokyoHO

Oct 31, 2015

-OO

IPPC2015 @ Tokyo

Biomaterial Science by Toshiharu Enomae

39

2015_all slides

Bacterial culture
Conclusion

10 µm

Gel that formed onhydrophilic areas

Oct 31, 2015

Colonies of bacteria growing
on medium after 24 h

IPPC2015 @ Tokyo

Hydrogel medium was successfully
formed by reaction on semihydrophilic areas of filter paper withmulti-cartridge ink-jet printer. The
growth of bacteria was successfully
observed with optical microscope.

Oct 31, 2015

IPPC2015 @ Tokyo

Influence of saltwater immersion onproperties of flood-damaged paper
Tunchira Bunyaphiphat
Akiko Nakagawa-Izumi
Toshiharu Enomae

Oct 31, 2015

IPPC2015 @ Tokyo

Mold grows and• Characters cannot beread due to color• Bad smell• Health hazard
Flood-damaged paper and books • Artistic value lost
To inhibit mold growth
WashingDryingRestoration… Speedy action is difficult!

Immersion in saltwater

0%

2.0%

• As NaCl
concentration
increases, bacteria
grew less (top), and• fibers swelled less(right).

3.0%

3.5%
Pure water
NaCl aq. sol.

was proposed.

Biomaterial Science by Toshiharu Enomae

40

2015_all slides

International alliances
Tsukuba
Vocational college of paper
technology and electro mechanics
Vietnam Forestry University

Asian Institute ofTechnology, Thailand

Chulalongkorn
University, Thailand

Zhejiang
University of
Science andTechnology , China

University of Technical
Education Ho Chi Minh City
Royal University ofPhnom Penh, Cambodia
Center for Pulp andPaper, Indonesia

Production of paper and paperboard
120

Surface chemistry - Contact angle

China
(a)
USA
(b)
Japan
(c)
Germany
Sweden
Korea
CanadaFinland
BrazilIndonesia
India
Thailand100

Production , million ton

Thank you for attention.

80

60

40

20

0

Q. What is the contact angle θc of sized paper?
 Sizing agent need not cover the whole surfaceof fibers for repelling water. If a sizing agent
covers 1% of the whole surface, what is thecontact angle θ ?
 Assume that θ is 0˚ for unsized fibers and 120˚
for the covering size.
θc(w) × cos 0º +
 cosθc = 0.95(x) × cos 120º
0.05
Paper
cosθc = 0.95 –(y)0.025(z)θc = 22.3º

Size1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012

Liquid absorption theory - Capillary model
Q. Substitute the relation represented in the figure into
the H-P equation and develop the Lucas-Washburn equation.
Softwood pulp fiber

Hardwood pulp fiber

H-P equation

2γ cos θ
r
Adl
dV
Q=
= πr 2dt
dt
Substitute

πPr 4
Q=
8ηl


Chemical pulp－Fiber geometry

P=

dl

2dl
dV = πrA

r

Lucas-Washburn equationl=dtrγ cos θ ⋅ t2η

Biomaterial Science by Toshiharu Enomae Copy paper

consists of(d) wood pulp fibers
 Observe pulps

41