WO2007037501A1

WO2007037501A1 - Resin composition for forming ultraviolet absorbing layer and laminate comprising ultraviolet absorbing layer

Info

Publication number: WO2007037501A1
Application number: PCT/JP2006/319818
Authority: WO
Inventors: Nobuhisa Noda
Original assignee: Nippon Shokubai Co., Ltd.
Priority date: 2005-09-27
Filing date: 2006-09-27
Publication date: 2007-04-05
Also published as: JP5102769B2; CN101258189A; EP1928941A4; TWI370152B; CN102085737B; WO2007037501A9; US20090110936A1; US8003222B2; KR20080049088A; KR100972473B1; JP2009510189A; EP1928941A1; TW200726797A; CN101258189B; CN102085737A

Abstract

The object of the present invention is to find a resin composition for forming an ultraviolet absorbing layer having excellent adhesion to various plastic substrates such as polyester type films of PET etc. and provide a laminate of plastic substrate having no yellowing, excellent weather resistance and less curl formation with good productivity. There is provided a resin composition for use in forming an ultraviolet absorbing layer on the surface of a plastic substrate, having an ultraviolet absorbing polymer as a major component being synthesized from monomer mixtures containing an ultraviolet absorbing monomer, wherein the resin composition contains 0.5-5 parts by mass of a saturated polyester resin with a number-average molecular weight of 10000 or more and 0.1-30 parts by mass of a polyisocyanate based crosslinker relative to 100 parts by mass of the ultraviolet absorbing polymer, and a laminate with an ultraviolet absorbing layer made of the above composition formed on the surface of a plastic substrate.

Description

DESCRIPTION

RESIN COMPOSITION FOR FORMING ULTRAVIOLET AB

LAYER AND LAMINATE COMPRISING ULTRAVIOLET AB

LAYER

TECHNICAL FIELD ' ^{

The present invention relates to a resin composition for

ultraviolet absorbing layer having excellent adhesion to plastic

and capable of preventing yellowing of films induced by ultravio

effectively, and a laminate suitable for optical applications havi

yellowing, less curl formation with good productivity

BACKGROUND ART ^~ ' '

Plastic substrates used in various applications are gene

ultraviolet light, when being exposed continuously with sun ligh

C from breakage of polymer main chain gradually, resultinglή a g

lowering of strength as a substrate Thus, a lot of studies have b

providing an absorbing layer of ultraviolet light for these plasti

(for example, Japanese Unexamined Patent Publication No HI

•I

Japanese Unexamined Patent Publication No 2003 107690^~aήd dicarboxylic acid as a raw material, and therefore, it contains a

ring in the backbone of polyester The aromatic ring is deterio

colored by ultraviolet light to generate yellowing of the film, so

ultraviolet absorbing layer is required more than other plasties

However, polyesters like PET crystallize easily, particul

stretched films are poor in adhesion due to high crystalline orie

have a weak adhesion to a layer to be laminated Thus, ordinari

type films are subjected to adhesion enhancing treatments such

discharge treatment, plasma treatment, treatment using an alk

compound solution, high, frequency sputter etching treatment a

of easy adhesion layer (undercoat layer) to laminate an ultravio

layer (e g Japanese Unexamined Patent Pubhcation No HIl 3

example, while an untreated PET film has a surface wetting in

35 mN/m measured according to JIS K 6768 in 2004 version, w

adhesion enhancing treatment is conducted, the index can be in

mN/m or more_* as a result, the adhesion to ultraviolet absorbin

remarkably improved <

However, there are many treatments with difficult condi

arrangements in the above adhesion enhancing treatments, an

also an additional step, so that it is required to skip the adhesio were poor in stability of resin liquids for forming ultraviolet abs

Further, crosslinkers requiring longer time and higher tempera

closslink are used in some cases, so there existed a room for im

from the point of saving costs

Meanwhile in the fields of thin model display and mobil

, addition to cost cutting by shortening steps, further miniaturiz

of members i e thinner type and weight saving are required O

members, there is a thin film having ultraviolet absorbing perfo

in the case of one side lamination on a substrate with an ultrav

absorbing layer, upon hardening the ultraviolet absorbing layer,

shrinks to cause the film to curl remarkably in some cases' Whe

occurs, there have been problems that troubles take place upon l

the following step with other functional layers such as a hard c

an adhesive layer, and films are abraded due to contact with rol

therefore, particularly, productivity of film m an optical applica

remarkably lowered

DISCLOSURE OF THE INVENTION * ^{ '

Thus, an object of the present invention is to find a resi

for forming an ultraviolet absorbing layer having excellent adhe

the present invention that can solve the above problems is used

ultraviolet absorbing layer on the surface of a plastic substrate,

ultraviolet absorbing polymer as a major component being synt

monomer mixtures containing an ultraviolet absorbing monome

characterized in that the resin composition contains 0 5 5 parts

saturated polyester resin with a number average molecular wei

or more and 0 1 30 parts by mass of a polyisocyanate based cros

relative to 100 parts by mass of the ultraviolet absorbing polym

The laminate comprising an ultraviolet absorbing layer

present invention is summarized as a laminate that an ultravio

layer is formed on the surface of a plastic substrate, wherein th

has a yellowing factor Δb of 2 or less before and after irradiatio

ultraviolet light of 120 mW/cm² from the side of ultraviolet abso

for 240 hours under an atmosphere of 80⁰C and 60% RH and cr

adhesion between the plastic substrate and the ultraviolet abso

95% or more

The resin composition for forming an ultraviolet absorbi

the present invention contains a saturate polyester resin in a sp

amount, so that an ultraviolet absorbing layer having excellent BEST MODE FOR CARRYING OUT THE INVENTION "

The resin composition for forming an ultraviolet absorbi

the present invention can form an ultraviolet absorbing layer %

adhesion and excellent ultraviolet absorbing performance to ev

plastic films having a surface wetting index of about 35 mN/m

according to JIS K 6768 in 2004 version • '

• First, a plastic substrate of interest to be coated with a

composition of the present invention is mainly a polyester type

polyester type film is a film obtained from polyester containing

ring potentially causing yellowing in the backbone chain as^la r

The example includes homopolyester films such as a polyethyle

terephthalate (PET), polyethylene naphthalate and polybutylen

terephthalate film, and also saturated polyester resin films des

They may be a monoaxially stretched or a biaxially stretched fil

stretched PET films are available, for example O PET manufac

Kanebo Trinity Holdings, Ltd *

In addition, a resin composition of the present invention

applied to films other than polyester type films Examples 'of th

substrate film include polyethylene, polypropylene, triacetyl cel

polyacrylate, polymethylmethacrylate, polystyrene, polycarbon

' ZERONEX (registered trademark) manufactured by Zeon Corp

OPTREZ (registered trademark) manufactured by Hitachi Che

Further, there may be used a polymer film having a lactone str

shown in the following general formula (l)

'

wherein R¹, R² and R³ each independently represent a h

or an organic residual group with a carbon number of 1 20 Add

organic residual group may contain an oxygen atom As the abo

residual group, an alkyl group with a carbon number of 1 20, a

group, a cycloalkylene group and an aromatic ring can be listed

Conventionally known additives may be added to these substra

including sheets ' '

It is preferable that a plastic substrate of interest in the

invention has a surface wetting index (JIS K 6768) of less than

Next, a resin composition for forming an ultraviolet abs

of the present invention will be described The resin compositio

ultraviolet absorbing polymer as a major component being synt

wherein R⁴ represents a hydrogen atom, a halogen ato

group with a carbon number of 1 8, an alkoxy group with *a^* carb

1 4, a cyano group or a nitro group, R⁵ represents a liner or bra

alkylene group having an element with a carbon number of 1 1

represents a liner or branched alkylene group with a carbon nu

or a group having an element capable of forming a hydrogen bo

represents a hydrogen atom or a methyl group, and R⁷ represen

atom or a hydrocarbon group with a carbon number of 1 8 ^J

In addition, the group capable of forming a hydrogen bo

R⁵ is a group that forms a hydrogen bond between polymer mol

synthesis and has an enhancing function of mechanical propert

such as flex resistance and water resistance_* specifically, the ex

include NH , CH₂NH , OCH₂CH(OH)CH₂O, and ⁱ u

CH₂CH₂COOCH₂CH(OH)CH₂O ^*

Preferable examples of the benzotriazole based monome

the above formula (l) are ^M

' ' 5' (meth)acryloyloxyethylphenyl] 2H benzotπazole,

2 [2' hydroxy 5' (β (meth)acryloyloxyethoxy) 3' tert butylphenyl

2H benzotriazole,

2 [2' hydroxy 3' (meth)acryloylaminophenyl] 2H benzotriazole,

2 [2' hydroxy 3' (meth)acryloylaminomethylphenyl] 2H benzotr

2 [2' hydroxy 3' (meth)acryloylamino 5' tert octylphenyl] 2H be

2 [2' hydroxy 3' (meth)acryloylaminomethyl 5' tert octylphenyl]

azole, i

2 [2' hydroxy 3' tert octyl 5' (meth)acryloylaminophenyl] 2H be

2 [2' hydroxy 3' tert octyl 5' (meth)acryloylaminomethylphenyl]

azole, and »

2 [2' hydroxy 5' (3 (meth)acryloyloxy 2 hydroxypropoxy) 3' tert

2H benzotriazole These can be used alone or in a mixture of t

kinds thereof »

In the present invention, a benzophenone based monom

benzophenone bone structure having an ultraviolet absorbing p

shown in the following formula (3) can be used as an ultraviolet

CH₂ (3

hydrogen atom or a methyl group, and R¹³ represents a hydroge

hydrocarbon group with a carbon number of 1 8

Examples of the benzophenone based monomer include

2 hydroxy 4 [2 (meth)acryloyloxy]ethoxybenzophenone,

2,2' dihydroxy 4 [2 (meth)acryloyloxy]ethoxybenzophenone,

2 hydroxy 3 tert butyl 4 [2 (meth)acryloyloxy]ethoxybenzophen

2 hydroxy 4 [2 hydoxy 3 (methjacryloyloxylpropoxybenzopheno

Also, a triazine based ultraviolet absorbing monomer sh

following formula (4) can be used ^*

¹⁴ Examples of the triazme based monomer include

2,4 diphenyl 6 [2 hydroxy 4 (2 acryloyloxyethoxy)phenyl] s tria

2,4 bis(2 methylphenyl) 6 [2 hydroxy 4 (2 acryloyloxyethoxy)ph

triazine, and

2,4 bis(2 methoxyphenyl) 6 [2 hydroxy 4 (2 acryloyloxyethoxy)p

triazine

, In the case of synthesis of ultraviolet absorbing polymer

present invention, a monomer having an ultraviolet stability gr

(ultraviolet stability monomer) may be used in addition to the a

ultraviolet absorbing monomer In particular, when an ultraviol

monomer and an ultraviolet stability monomer are concomitant

resultant polymer has both ultraviolet absorption and ultraviol

which provides a prolonged weather resistance The kind of ultr

stability monomer is not particularly limited as long it has both

polymerizable double bond and ultraviolet stability group in a

particularly preferable is a monomer shown in the following for

atom or an imino group

Examples of the monomer represented by the above for

include, but not limited to,

4 (meth)acryloyloxy 2,2,6,6 tetramethylpiperidine, for example,

LA87 manufactured by Adeka Corporation,

4 (meth)acryloylamino 2,2,6,6 tetramethylpiperidine, '

4 (meth)acryloyloxy 1,2,2,6,6 pentamethylpiperidine, for examp

Adekastab LA82 manufactured by Adeka Corporation, '

4 (meth)acryloylamino 1,2,2,6,6 pentamethylpiperidine,

4 cyano 4 (meth)acryloylammo 2,2,6,6 tetramethylpiperidine,

4 crotonoyloxy 2,2,6,6 tetramethylpiperidine, and

4 crotonoylamino 2,2,6,6 tetramethylpiperidine, and these ultr

stability monomers may be used alone, and if desired, suitably i

combination of two or more kinds thereof ^{

In the case of synthesis of ultraviolet absorbing polymer

present invention, it is preferable to copolymerize the above ult

absorbing monomer and ultraviolet stability monomer as well i

with monomers without ultraviolet absorbing performance (refe

monomers) Characteristics of ultraviolet absorbing polymer ob

variously changed by choosing the kind and amount of other mo (meth)acrylate, 2 hydroxybutyl (meth)acrylate, 4 hydroxybutyl

(meth)acrylate, and caprolactone modified hydroxyl (meth)acryl

example, Prakcel F series manufactured by Daicel Chemical In

(Meth)acrylates capable of synthesizing a polymer havi

weather resistance and having good copolymerization capabilit

ultraviolet absorbing momomers exemplified above are also pre

examples are listed as follows methyl (meth)acrylate, ethyl (me

n propyl (meth)acrylate, isopropyl acrylate, n butyl (meth)acryl

(meth)acrylate, sec butyl (meth)acrylate, tert butyl (meth)acryl

(meth)acrylate, isoamyl (meth)acrylate, heptyl (me th) acrylate,

(meth)acrylate, isooctyl (meth)acrylate, 2 ethylhexyl (meth)acry

cyclohexyl (meth)acrylate, nonyl (meth)acrylate, isononyl (met'h

isodecyl (meth)acrylate, dodecyl (meth)acrylate, tridecyl (meth)

n lauryl (me th) acrylate, n stearyl (meth)acrylate, isostearyl (m

dicyclopentanyl (meth)acrylate, isobornyl (meth)acrylate, <■

2 acetoacetoxyethyl (meth)acrylate, for example, Eastman AAE

manufactured by Eastman Corporation, and phenoxyethyl (met

These can be used alone or in a mixture of two or more kinds th

As other monomers, there can be used the following vari

monomers > < monomers containing silicon such as vinyltrichlorosilan

vinyltπs(β methoxyethoxy)silane, vinyltπmethoxysilane,

vinyltπethoxysilane, γ (meth)acryloxypropyltrimethoxysilane

trimethylsiloxyethyl (meth)acrylate, •

monomers containing halogen such as trifluoroethyl (m

2,2,3,3 tetrafluoropropyl (me th) aery late, hexafluoropropyl (met

octafluoropentyl (me th) aery late, heptadodecafluorodecyl (meth)

β (perflorooctyDethyl (meth)acrylate, 3 chloro 2 hydroxypropyl

(me th) aery late, ethylene oxide adduct of tnbromophenol (meth)

tribromophenyl (meth)acrylate>

monomers containing nitrogen such as (meth)acrylamid

bis(meth)acrylamide, N methylol (metlOacrylamide,

(meth)acryloyloxyethyltπmethyl ammonium chloride, dimethyl

(meth)acrylate sulfate, ethylene oxide adduct of morpholine (m

N vinyl pyridine, N vinyl imidazole, N vinyl pyrrole, N vinyl py

N vinyl oxazolidone,»N vinyl succimmide, N vmylmethyl carba

N,N methylvinylacetoamide and 2 isopropenyl 2 oxazohne>

multi functional monomers such as ethylene glycol di(m

diethylene glycol di(meth) aery late, polyethylene glycol di(meth)

propylene glycol di(meth)acrylate, polypropylene glycol di(meth 2,2 bis[4 (methacryloxypolyethoxy)phenyl]proρane di(meth)acr

ethylene oxide modified bisphenol A di(meth)acrylate, and prop

modified bisphenol A di(meth)acrylate trimethylol propane '

tri(meth) aery late, «

vinyl ethers such as vinyl methyl ether, vinyl ethyl ethe

isopropyl ether, vinyl n propyl ether, vinyl isobutyl ether, vinyl

vinyl n amyl ether, vinyl isoamyl ether, vinyl 2 ethylhexyl ethe

n octadecyl ether, cyanomethyl vinyl ether, 2,2 dimethylaminoe

ether, 2 chloroethyl vinyl ether, β difluoromethyl vinyl ether, be

{ether, phenyl vinyl ether, divinyl ether and divinyl acetaL 1

monomers containing an epoxy group such as glycidyl (

α methylglycidyl acrylate, α methylglycidyl methacrylate, for e

MGMA manufactured by Daicel Chemical Industries Co , ^*Ltd , '

3,4 epoxycyclohexylmethyl acrylate, for example, Cyclomer A4Θ

manufactured by Daicel Chemical Industries Co , Ltd , * *

3,4 epoxycyclohexylmethyl methacrylate, for example, Cyclome

manufactured by Daicel Chemical Industries Co , Ltd , and '

monomers containing an acidic functional group such as

(me th) acrylate, 2 (meth)acryloyloxyethyl acid phosphate and

2 (meth) aery loyloxyp ropy 1 acid phosphate The ultraviolet absorbing monomer is preferably 5% by

mass%) or more, more preferably 10 mass% or more, further pr

mass% or more, and 80 mass% or less, more preferably 70 mass

further preferably 50 mass% or less This range provides a^δ suffi

ultraviolet absorbing performance and can prevent a polyester t

yellowing for a long period of time When an ultraviolet stabilit

used, it is preferably 0 1 mass% or more, more preferably 0 5 m

and 20 mass% or less, more preferably 10 mass% or less A mon

containing a hydroxyl group is preferably 2 mass% or more, mo

4 mass% or more and 35 mass% or less, more preferably 25 ma

Also, other monomers are used as the remaining of the

monomers From the point of enhancing physical properties of

absorbing layer, methyl methacrylate and cyclohexyl methacryl

preferred

A polymerization method for synthesizing an ultraviolet

polymer of the present invention is not particularly limited, an

polymerization methods can be used such as solution polymeriz

polymerization, aqueous solution polymerization, suspension po

and emulsion polymerization methods The solution polymeriza

is preferable because the resultant reaction product can be as it

^{* i} cellosolve acetate » ketone type solvents such as methyl ethyl ke

isobutyl ketone and cyclohexanone, and dimetyl formamide Th

solvent used is not limited thereto These solvents may be used

mixed solvent of two or more kinds thereof The amount of solv

be suitably determined in view of monomer concentration,' desi

weight of polymer and polymer solution concentration ^u '

As a polymerization initiator usable in the solution poly

the examples that can be used include known radical polymeriz

initiators such as 2,2' azobis (2 methylbutyronitrile), ^J

tert butylperoxy 2 ethylhexanoate, 2,2' azobisisobutyronitnle,

peroxide and di tert butyl peroxide The amount of polymerizat

used is not particularly limited, but it is preferably 0 01 mass%

mass% or less, and more preferably 0 05 mass% or more, 20 ma

relative to the total of monomers Also, if required, a chain tran

like n dodecylmercapton may be added in one or more kinds to

molecular weight of polymer '*

Temperature in the polymerization reaction is also not p

limited, but it is preferably m a range of room temperature to' 2

more preferably in a range of 40 to 140⁰C Additionally, reactio

suitably chosen to complete polymerization reaction efficiently becomes insufficient The upper limit is preferably 300000, and

preferably 200000 When Mw exceeds 300000, it is not preferab

stability of resin liquid after polyisocyanate based crosslinker is

will be lowered » ■

Next, saturated polyester resin will be described Exam

saturated polyester resin that can be used include (co)polycond

obtained by known methods of one or more kinds of polyhydric

components such as ethylene glycol, propylene glycol, 1,3 butyl

1.4 butylene glycol, 1,6 hexanediol, diethylene glycol, dipropyle

triethylene glycol, hydrogenated bisphenol A, neopentyl gycol,

1.5 pentanediol, 3 methyl 1,5 pentanediol, 2 butyl 2 ethyl 1,3 p

1,4 cyclohexane dimethanol, 1,9 nonanediol, 2,2 dimetyl 3 hydr

acid, 2,2 dimethyl 3 hydroxypropyl, glycerin, trimethylol ethan

propane, pentaerythritoL with one or more kinds of polycarboxy

components such as aromatic dicarboxylic acids such as terepht

isophthalic acid, naphtharene 1,4 or 2,6 dicarboxylic acid/and

5 sodiumsulfoisophthalic acid> aliphatic dicarboxylic acids such

acid, azelaic acid, sebacic acid, 1,3 cyclohexane dicarboxylic ad

1,4 cyclohexane dicarboxylic acid, and derivatives such as their

esters and diaryl esters ⁾ TP 220, TP 235, TP 236, TP 290, TP 249, WR 905 and WR 901

trademark), manufactured by Nippon Synthetic Chemical Indu

Espel series of 9940A, 9940B, 9940D, 9940E 37 and 9940A 37 (

trademark) manufactured by Hitachi Chemical Co , Ltd

A number average molecular weight Mn of saturated po

is preferably 10000 or more When Mn is less than 10000, adhe

substrate becomes insufficient In addition, curl resistance &lso

lowered The Mn is more preferably 20000 or more

The saturated polyester resin may preferably have a gla

temperature of higher than 50⁰C, more preferably higher than

the saturated polyester resin has a glass transition temperatur

higher than 50⁰C, the blocking property of ultraviolet absorbing

may be deteriorated and the adhesion of ultraviolet absorbing c

the weather resistance test may be reduced

The third essential component of the present invention i

polyisocyanate based crosslinker It undergoes crosslinking reac

hydroxyl group introduced into an ultraviolet absorbing polyme

monomer containing the foregoing hydroxyl group to enhance w

resistance, strength and chemical resistance of ultraviolet absor

Other crosslinkers such as melamine resin need a higher tempe diisocyanate (TDI) and 4,4' diphenylmethane diisocyanate (MD

polyisocyanate compounds such as Sumidur N (registered trade

polyisocyanate compounds containing an isocyanurate ring(s) s

Desmodur IL (registered trademark), Desmodur HL, manufact

Sumika Bayer Urethane Co , Ltd and Colonate EH (registered

manufactured by Nippon Polyurethane Industry Co , Ltd > addu

polyisocyanate compounds like Sumidur L manufactured by Su

Urethane Co , Ltd adduct polyisocyanate compounds like Colo

Colonate L 55E manufactured all by Nippon Polyurethane Indu

These can be used alone or in combination of two or more kinds

so called block isocyanate compound that the isocyanate group

compounds is reacted with a masking agent having active hydr

deactivated can also used , , *

In a resm composition for forming an ultraviolet absorbi

the present invention, regarding a formulation ratio of each of e

components, a saturated polyester resin is of 0 5 5 parts by mas

100 parts by mass of the ultraviolet absorbing polymer Less a

saturated polyester resin lowers the adhesion to a substrate an

resistance The lower limit is more preferably 1 part by mass H

a content of saturated polyester resin exceeds 5 parts by mass, i (dry content) relative to 100 parts by mass of the ultraviolet abs

polymer Less crosslinker lowers the adhesion to a substrate, w

exceeding 30 parts by mass, the stability of resin liquid after ^r>

crosslinker formulation is lowered The upper limit is more pre

parts by mass ^v

' A resin composition for forming an ultraviolet absorbing

present invention can be obtained by suitably mixing these solv

synthesis of ultraviolet absorbing polymer or the usable solvent

as a medium A resin composition may contain other additives

include ordinary additives m a coating field organic class ultra

absorbents such as benzotriazole type, benzophenone type, tria

indole type, inorganic class ultraviolet absorbents such as zinc o

addition type ultraviolet stabilizers such as steric hindrance pip

compounds like Tuiuvin 123, Tinuvin 144 and Tinuvin 765 man

Chiba Specialty Chemicals Corporation? leveling agents, antioxi

like talc, antirusts, fluorescent whitening agents, antioxidants,

agents, pigments, dyes, thickeners, inorganic particles like collo

and alumina sol, acryl based fine particle's like polymethylmeth

In the case of using these other additives, the amount of ultravi

absorbing polymer of the present invention in an ultraviolet abs coat, spin coat, bar coat and electrostatic coating Drying tempe

chosen suitably to solvent ^u

According to Lambert Beer law, thickness of ultraviolet

layer depends on the amount of ultraviolet absorbing group int

polymer, namely the amount of ultraviolet absorbing monomer

polymerization Accordingly, the thickness of layer can be deter

consideration of the amount of ultraviolet absorbing group in t

weather resistance and ultraviolet absorbing performance requ

laminate layer containing an ultraviolet absorbing layer Ordin

range of 0 5 20 μm When thickness is more than 20 μm, it tak

coating and curl resistance is also lowered Reversely, when thi

than 0 5 μm, it is difficult to coat uniformly on a substrate and t

of insufficient ultraviolet absorbing performance The lower lim

thickness is more preferably 1 0 μm and the upper limit is mor

•15 μm •

The ultraviolet absorbing layer obtained by the resin co

forming a ultraviolet absorbing layer of the present invention is

ultraviolet absorbing performance, and a laminate having a sub

which the ultraviolet absorbing layer is formed is excellent in y

resistance A target of yellowing resistance for a laminate was c manufactured by Iwasaki Electric Co , Ltd , b values before and

irradiation of ultraviolet light of 120 mW/cm² from the side of u

absorbing layer for 240 hours under an atmosphere of 80⁰O and

(relative humidity) were measured by a spectral color differenc

SE 2000 manufactured by Nippon Denshoku Co , Ltd by a refle

according to JIS K 7105 (2004 version), and the difference of b

and after irradiation was defined as a yellowing factor Δb The ^!

preferably 1 5 or less and more preferably 1 or less Additionally

described below, the results were evaluated as partly inferior (

or more, less than 4, and as inferior ( X ) for Δb of 4 or more * ⁽ ±

The ultraviolet absorbing layer of the present invention

adheres to a substrate Adhesion is evaluated by a cross cut ad

and it can be said to be excellent for 90% or more Specifically, i

with JIS K 5600 5 6 (2004 version), from the side of ultraviolet

layer of laminate, the laminate was scotched into 100 cross cut

mm square up to a substrate through the ultraviolet absorbing

cutter knife with a cutter guide of 1 mm spacing, and a cellopha

tape CT405AP 18 with 18 mm wide manufactured by Nichibaii

attached to the scotched surface completely by rubbing with a r

from above, then peeled off vertically to observe with the naked higher the number, the more excellent is the cross cut adhesion

The ultraviolet absorbing laminate obtained by using th

composition for forming an ultraviolet absorbing layer of the pr

invention does not cause inconvenience like curl Regarding cur

an ultraviolet absorbing layer was formed on a plastic substrat

case of coating, coated and dried, and within 30 minutes, the ob

laminate was placed in an atmosphere of 23°C and 65% RH, an

of 10 cm by 3 cm was cut out from the laminate, placed on' a hor

having the ultraviolet absorbing layer upwards, and the distan

each of its four corners and the horizontal board, i e floating di

measured_* the total length was evaluated as good (O) for 0 mm

than 3 mm, partly inferior (Δ) for¹3 mm or more, less than⁵5 m

inferior ( X ) for 5 mm or more *

Examples *

The present invention will be described in detail with re

Examples and Comparative examples below, but the present in

to be limited thereto, and can be *

suitably modified and conducted to the extent that is in confor

spirit described above and below, and are included in the techni thermometer, a reflux condenser and a nitrogen gas introducin

loaded with 30 parts of ^{l >}

2 (2' hydroxy 5' methacryloyloxyethylphenyl) 2H benzotπazole

(trade name? referred to UVAl) manufactured by Otsuka Chem

57 parts of methyl methacrylate (MMA), 8 parts of 2 ethylhexyl

(2EHA), 5 parts of 2 hydroxyethyl methacrylate (HEMA) and 7

ethyl acetate, and heated with introducing a nitrogen gas while

reflux temperature At the same time, in a initiator dropping ta

of 20 parts of ethyl acetate and 1 0 parts of 2,2' azobis(2 methyl

was loaded, and added dropwise into the flask over 2 hours Aft

of dropping, reflux reaction was continued, and after 6 hours 'fro

of dropping, cooled and diluted with ethyl acetate so that non v

becomes 50% '

The thus obtained ultraviolet absorbing polymer 1 was

a weight average molecular weight (Mw) by GPC HLC8120 ma

by Tosoh Corporation and using a column TSK GEL GMHXL L

manufactured by Tosoh Corporation, as a polystyrene reduced

weight The results are shown in Table 1

Synthesis examples 2 7 Additionally, in Table 1, UVA2 is >' _*

2 hydroxy 4 (2 acryloyloxyethoxy)benzophenone, UVA3 is

2 [2 hydroxy 4 (2 methacryloyloxyethoxy)phenyl] 4,6 dipheriyl

UVA4 is

2 (2H benzotriazol 2 yl) 6 methacryloylaminomethyl 4 (1,1,3,3

utyl)phenol, CHMA is cyclohexyl methacrylate, and LA82 is ^{i π}

1,2,2,6,6 pentamethyl 4 pyperidyl methacrylate Adekastab LA

name) manufactured by Adeka Corporation, and FMID is ¹I mol

caprolactone adduct of 2 hydroxyethyl methacrylate Placcel F

name) manufactured by Daicel Chemical Industries Ltd ' ' ^;

Table 1

to

Example 1

In a container were loaded 200 parts (wet) of the polyme

Synthesis example 1, 2 parts of saturated polyester resin Vyloή

(registered trademark_* Mn 18000, denoted as Vylon l) manufac

Toyobo Co , Ltd and 6 9 parts of polyisocyanate based crosslink

N3200 (registered trademark) manufactured by Sumika Bayer

Ltd , further diluted with ethyl acetate so that non volatile part

solution to prepare a resin composition for forming an ultraviol

layer (resin liquid)

To evaluate the stability of this resin liquid, a suitable a

sampled immediately after the liquid was prepared to measure

with a B type viscometer The viscosity was also measured after

was allowed to stand at 25°C for 24 hours with a B type viscom

stability of resin liquid was evaluated from an increase in visco

following criterion

O (good) (viscosity after 24 hour standing - initial viscosity) i

mPa s _r ⁿ

Δ (partly inferior) (viscosity after 24 hour standing - initial vi

mPa s or more, less than 10 mPa s

X (inferior) (viscosity after 24 hour standing - initial viscosity) absorbing layer was formed on PET film ^!

The laminate was measured for yellowing factor Δb by t

method The cross cut adhesion was also measured by the* foreg

The initial cross cut adhesion before weather resistance test an

adhesion after irradiation of ultraviolet light of the same irradi

and irradiation time as in the measurement of yellowing factor

measured Further, the curl resistance was also measured by th

method ^} *•

The results of various measurements are shown in Tabl

Additionally, Vylon 2 in Table 2 is a saturated polyester resin V

6000) manufactured by Toyobo Co , Ltd , and Espel is a saturat

resin Espel 9940Z 37 (Mn 10000) manufactured by Hitachi Che

Ltd and a melamine based crosslinker is Cymel 370 manufactu

Cytec, Ltd _x

Examples 2 6, Reference examples 1 2 Comparative examples

A laminate having an ultraviolet absorbing layer formed

was obtained in the same manner as in Example 1 except that t

formulated composition was changed as shown in Table 2¹ Addit

Example 5 employed an untreated polyethylene naphthalate fil Table 2

to

CD

INDUSTRIALAPPLICABILITY '

A resin composition for forming an ultraviolet absorbing

present invention contains a saturated polyester resin in a spec

so that an ultraviolet absorbing layer having excellent adhesion

plastic substrates, especially an untreated plastic film on which

enhancing treatment had not been performed, was able to be fo

result, it became possible to provide a laminate having excellen

resistance and yellowing resistance with low costs

A resin composition for forming an ultraviolet absorbing

present invention can be used in deterioration protection applic

protecting contents and substrates from ultraviolet light, for ex

coating agents for forming an ultraviolet absorbing layer such a

materials of medicines, foods etc and on glass bottles There ca

as coating agents for preventing coloring material like dyes fro

deterioration, agglutmants and adhesives for bonding plastic su

each other like fluorine resin films, or primers for hard coat lay

type and acryl type Furthermore, it can be used in recording li

weather resistance, fiber treating agents and insulation coating

insulating devices and display devices

A laminate comprising an ultraviolet absorbing layer of solar battery, polymer solid electrolyte, ultraviolet absorbing in

various type optical films such as polarization plate protecting

anti reflection film, reflection film and light diffusion film, film

materials such as glass anti scattering film, decoration film ari

window, indoor and outdoor overlay films such as display mater

electric spectacular signboards and shrink film

Claims

CLAIMS »

1 A resin composition for use in forming an ultraviole

layer on the surface of a plastic substrate, having an ultraviolet

polymer as a major component being synthesized from monome

containing an ultraviolet absorbing monomer,, wherein the resi

contains 0 5 5 parts by mass of a saturated polyester resin 'with

number average molecular weight of 10000 or more and 0 1 30

of a polyisocyanate based crosslinker relative to 100 parts by_^ma

ultraviolet absorbing polymer ^f

2 A laminate comprising an ultraviolet absorbing laye

the surface of a plastic substrate, wherein the laminate has a y

factor Δb of 2 or less before and after irradiation of ultraviolet li

mW/cm² from the side of ultraviolet absorbing layer for 240 hou

atmosphere of 80⁰C and 60% RH and cross cut adhesion betwee

substrate and the ultraviolet absorbing layer of 95% or more