U.S. patent application number 16/465492 was filed with the patent office on 2020-02-27 for adhesive composition, adhesive layer and adhesive sheet.
The applicant listed for this patent is NITTO DENKO CORPORATION. Invention is credited to Ryoko ASAI, Yoshiko KIRA, Kenichi OKADA, Kayo SHIMOKAWA, Kensuke TANI.
Application Number | 20200063004 16/465492 |
Document ID | / |
Family ID | 62565263 |
Filed Date | 2020-02-27 |
United States Patent
Application |
20200063004 |
Kind Code |
A1 |
ASAI; Ryoko ; et
al. |
February 27, 2020 |
ADHESIVE COMPOSITION, ADHESIVE LAYER AND ADHESIVE SHEET
Abstract
The present invention relates to an adhesive composition
containing a base polymer, a water-absorbing material, and a
moisture-curable component, wherein the moisture-curable component
is contained in an unreacted state, an adhesive layer made from the
adhesive composition, and an adhesive sheet including the adhesive
layer.
Inventors: |
ASAI; Ryoko; (Ibaraki-shi,
Osaka, JP) ; SHIMOKAWA; Kayo; (Ibaraki-shi, Osaka,
JP) ; TANI; Kensuke; (Ibaraki-shi, Osaka, JP)
; KIRA; Yoshiko; (Ibaraki-shi, Osaka, JP) ; OKADA;
Kenichi; (Ibaraki-shi, Osaka, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
NITTO DENKO CORPORATION |
Ibaraki-shi, Osaka |
|
JP |
|
|
Family ID: |
62565263 |
Appl. No.: |
16/465492 |
Filed: |
November 29, 2017 |
PCT Filed: |
November 29, 2017 |
PCT NO: |
PCT/JP2017/042925 |
371 Date: |
May 30, 2019 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C09J 121/00 20130101;
C09J 153/02 20130101; C08G 18/7621 20130101; C09J 2423/00 20130101;
C09J 123/22 20130101; C09J 133/00 20130101; C09J 2421/00 20130101;
C09J 2409/00 20130101; C09J 7/32 20180101; C09J 201/00 20130101;
C09J 201/10 20130101; C09J 7/00 20130101; C09J 133/10 20130101;
C09J 7/30 20180101; C09J 11/08 20130101; C09J 2453/00 20130101;
C09J 11/06 20130101; C09J 135/00 20130101; C09J 143/04 20130101;
C09J 2433/00 20130101; C09J 7/20 20180101; C09J 133/10 20130101;
C08L 101/10 20130101; C08L 101/14 20130101; C09J 133/10 20130101;
C08L 23/26 20130101; C08L 43/04 20130101 |
International
Class: |
C09J 133/10 20060101
C09J133/10; C09J 121/00 20060101 C09J121/00; C09J 135/00 20060101
C09J135/00; C09J 123/22 20060101 C09J123/22; C09J 7/20 20060101
C09J007/20; C08G 18/76 20060101 C08G018/76 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 30, 2016 |
JP |
2016-232749 |
Nov 29, 2017 |
JP |
2017-229394 |
Claims
1. An adhesive composition comprising a base polymer, a
water-absorbing material, and a moisture-curable component, wherein
the moisture-curable component is contained in an unreacted
state.
2. The adhesive composition according to claim 1, wherein a content
of the moisture-curable component is 0.1 to 50% by weight based on
all the components of the adhesive composition excluding a
solvent.
3. The adhesive composition according to claim 1, which exhibits an
initial elastic modulus of 400 kPa or less when forming an adhesive
layer.
4. The adhesive composition according to claim 1, wherein the
moisture-curable component is capable of chemically bonding to an
adherend.
5. The adhesive composition according to claim 1, wherein the
moisture-curable component is one or more selected from an
isocyanate compound and an alkoxysilyl group-containing
polymer.
6. The adhesive composition according to claim 1, wherein the base
polymer contains an acrylic polymer or a rubber-based polymer.
7. The adhesive composition according to claim 1, wherein the
content of the water-absorbing material is 1 to 50% by weight based
on all the components of the adhesive composition excluding a
solvent.
8. The adhesive composition according to claim 1, wherein the
water-absorbing material is a water-absorbing polymer.
9. An adhesive layer comprising the adhesive composition according
to claim 1.
10. The adhesive layer according to claim 9, wherein the
water-absorbing material is exposed at 0.5 to 80% of the surface
area of a pasting surface of the adhesive layer.
11. An adhesive sheet comprising the adhesive layer according to
claim 9.
12. The adhesive sheet according to claim 11, wherein the adhesive
layer is formed on a substrate.
Description
TECHNICAL FIELD
[0001] The present invention relates to an adhesive composition, an
adhesive layer made from the adhesive composition, and an adhesive
sheet including the adhesive layer.
BACKGROUND ART
[0002] Conventionally, a primer composition has been used for the
purpose of waterproofing of concrete and the like. For example,
Patent Literature 1 describes that a coating composition obtained
by mixing a specific resin composition and a specific
moisture-curable solution can be used as a primer composition
having excellent close adhesiveness to a wet surface.
[0003] Further, Patent Literature 2 describes a photopolymerizable
composition which can provide a moisture-curable adhesive having
sufficient adhesive strength to an adherend having an uneven
surface such as an inorganic material, e.g., concrete or the like,
or wood by photopolymerization, and a moisture-curable adhesive
sheet obtained by using this composition.
CITATION LIST
Patent Literature
[0004] Patent Literature 1: JP-A-2001-354749
[0005] Patent Literature 2: JP-A-2000-273418
SUMMARY OF INVENTION
Technical Problem
[0006] However, since the coating composition described in Patent
Literature 1 is used as a liquid primer composition and requires a
coating operation and subsequent drying, there is a problem in view
of operation efficiency.
[0007] Moreover, in Patent Literature 2, the adhesive strength to
an adherend having an uneven surface such as an inorganic material,
e.g., concrete or the like, or wood is investigated but the
adhesive strength to a wet surface is not investigated at all.
[0008] An object of the present invention is to provide an adhesive
composition which gives high adhesive force to a wet surface,
particularly to a wet surface of an adherend having unevenness, an
adhesive layer made from the adhesive composition, and an adhesive
sheet including the adhesive layer.
Solution to Problem
[0009] As a result of intensive studies in view of the above
problems, the present inventors have found that the problems can be
solved by an adhesive composition having the following
configuration, an adhesive layer made from the adhesive
composition, and an adhesive sheet including the adhesive layer,
and have completed the present invention.
[0010] One aspect of the present invention relates to an adhesive
composition containing a base polymer, a water-absorbing material,
and a moisture-curable component, wherein the moisture-curable
component is contained in an unreacted state.
[0011] In the adhesive composition, the content of the
moisture-curable component may be 0.1 to 50% by weight based on all
the components of the adhesive composition excluding a solvent.
[0012] In the adhesive composition, the moisture-curable component
may be capable of chemically bonding to an adherend.
[0013] The adhesive composition preferably exhibits an initial
elastic modulus of 400 kPa or less when forming an adhesive
layer.
[0014] In the adhesive composition, the moisture-curable component
may be one or more selected from an isocyanate compound and an
alkoxysilyl group-containing polymer.
[0015] In the adhesive composition, the base polymer may contain an
acrylic polymer or a rubber-based polymer.
[0016] In the adhesive composition, the content of the
water-absorbing material may be 1 to 50% by weight based on all the
components of the adhesive composition excluding a solvent.
[0017] In the adhesive composition, the water-absorbing material
may be a water-absorbing polymer.
[0018] Further, one aspect of the present invention relates to an
adhesive layer comprising the above-described adhesive
composition.
[0019] In the adhesive layer, the water-absorbing material may be
exposed at 0.5 to 80% of the surface area on a pasting surface of
the adhesive layer.
[0020] Moreover, one aspect of the present invention relates to an
adhesive sheet comprising the above-mentioned adhesive layer.
[0021] In the adhesive sheet, the adhesive layer may be formed on a
substrate.
Advantageous Effects of Invention
[0022] The adhesive layer made from the adhesive composition and
the adhesive sheet of the present invention have high adhesive
force to a wet surface, particularly to a wet surface of an
adherend having unevenness.
DESCRIPTION OF EMBODIMENTS
[0023] Hereinafter, embodiments of the present invention will be
described in detail.
[0024] An adhesive composition according to one embodiment of the
present invention is an adhesive composition containing a base
polymer, a water-absorbing material, and a moisture-curable
component, the moisture-curable component being contained in an
unreacted state.
[0025] When an adhesive layer made from the adhesive composition
according to the present embodiment or an adhesive sheet including
the adhesive layer (hereinafter collectively also referred to as
adhesive sheet) is pasted to a wet surface of an adherend, water on
the wet surface of the adherend is first absorbed and removed by
the water-absorbing material in the adhesive composition (adhesive
layer) and also the adhesive sheet is pasted to the adherend at
such an initial adhesive force that displacement does not occur,
owing to the adhesiveness of the adhesive layer. At this time,
since the water on the wet surface of the adherend is absorbed and
removed by the water-absorbing material, even if the adherend has
an uneven surface, the adhesive layer can well follow the uneven
surface of the adherend. In addition, the unreacted
moisture-curable component in the adhesive composition (adhesive
layer) reacts with the water absorbed from the wet surface of the
adherend or water such as the surrounding water or moisture to
undergo moisture curing, and thereby, the adhesive force to the
adherend is further increased. Therefore, the adhesive sheet of the
present embodiment can increase the adhesive force with time even
when pasted to the wet surface of the adherend, particularly to a
wet-state adherend having an uneven surface, and exhibits high
adhesive force. Incidentally, the case where the moisture-curable
component is capable of chemically bonding to the adherend is
preferred because the adhesive force to the adherend surface is
further improved by the progress of the chemical bond between the
moisture-curable component capable of chemically bonding to the
adherend contained in an unreacted state in the adhesive
composition (adhesive layer) and the adherend surface.
[0026] In the adhesive composition according to the present
embodiment, the base polymer constituting the adhesive composition
is not particularly limited, and known polymers used for adhesives
can be used. For example, acrylic polymers, rubber-based polymers,
vinyl alkyl ether-based polymers, silicone-based polymers,
polyester-based polymers, polyamide-based polymers, urethane-based
polymers, fluorine-based polymers, epoxy-based polymers, and the
like may be mentioned. Among them, rubber-based polymers and
acrylic polymers are preferable from the viewpoint of adhesiveness,
and rubber-based polymers having low moisture permeability are more
preferable from the viewpoint of water resistance. Incidentally, as
such a polymer, only one kind may be used alone, or two or more
kinds may be used in combination.
[0027] As a main monomer component constituting the acrylic
polymer, a (meth) acrylic acid alkyl ester ((meth)acrylic acid
alkyl ester having a linear or branched alkyl group) can be
suitably used. Examples of the (meth) acrylic acid alkyl ester
include (meth)acrylic acid alkyl esters having an alkyl group
having 1 to 20 carbon atoms, such as methyl (meth)acrylate, ethyl
(meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate,
butyl (meth)acrylate, isobutyl (meth)acrylate, s-butyl
(meth)acrylate, t-butyl (meth)acrylate, pentyl (meth)acrylate,
isopentyl (meth)acrylate, hexyl (meth)acrylate, heptyl
(meth)acrylate, octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate,
isooctyl (meth)acrylate, nonyl (meth)acrylate, isononyl
(meth)acrylate, decyl (meth)acrylate, isodecyl (meth)acrylate,
undecyl (meth)acrylate, dodecyl (meth)acrylate, tridecyl
(meth)acrylate, tetradecyl (meth)acrylate, pentadecyl
(meth)acrylate, hexadecyl (meth)acrylate, heptadecyl
(meth)acrylate, octadecyl (meth)acrylate, nonadecyl (meth)acrylate,
and eicosyl (meth)acrylate. Among them, (meth)acrylic acid alkyl
esters having an alkyl group having 1 to 14 carbon atoms are
preferable, and (meth)acrylic acid alkyl esters having an alkyl
group having 2 to 10 carbon atoms are more preferable.
Incidentally, the above "(meth)acrylic acid ester" represents
"acrylic acid ester" and/or "methacrylic acid ester", and the same
shall apply in others.
[0028] In addition, as (meth)acrylic acid esters other than the
above (meth)acrylic acid alkyl esters, examples thereof include
(meth)acrylic acid esters having an alicyclic hydrocarbon group,
such as cyclopentyl (meth)acrylate, cyclohexyl (meth)acrylate, and
isobornyl (meth)acrylate, and (meth)acrylic acid esters having an
aromatic hydrocarbon group, such as phenyl (meth)acrylate.
[0029] The (meth)acrylic acid esters can be used alone, or two or
more kinds can be used in combination. Incidentally, since the
(meth)acrylic acid ester is used as a monomer main component of the
acrylic polymer, the proportion of the (meth)acrylic acid ester
[especially (meth)acrylic acid alkyl ester] is, for example,
preferably 60% by weight or more, and more preferably 80% by weight
or more relative to the total amount of the monomer components for
preparing the acrylic polymer.
[0030] In the acrylic polymer, various copolymerizable monomers
such as polar group-containing monomers and polyfunctional monomers
may be used as monomer components. By using a copolymerizable
monomer as a monomer component, for example, the adhesive force to
the adherend can be improved, or the cohesive force of the adhesive
can be increased. The copolymerizable monomers can be used alone,
or two or more kinds can be used in combination.
[0031] Examples of the polar group-containing monomer include
carboxyl group-containing monomers such as (meth)acrylic acid,
itaconic acid, maleic acid, fumaric acid, crotonic acid, and
isocrotonic acid or anhydrides thereof (maleic anhydride etc.);
hydroxyl group-containing monomers such as hydroxyalkyl
(meth)acrylates, e.g., hydroxyethyl (meth)acrylate, hydroxypropyl
(meth)acrylate, hydroxybutyl (meth)acrylate, and the like; amide
group-containing monomers such as acrylamide, methacrylamide,
N,N-dimethyl(meth)acrylamide, N-methylol(meth)acrylamide,
N-methoxymethyl(meth)acrylamide, and
N-butoxymethyl(meth)acrylamide; amino group-containing monomers
such as aminoethyl (meth)acrylate, dimethylaminoethyl
(meth)acrylate, and t-butylaminoethyl (meth)acrylate; glycidyl
group-containing monomers such as glycidyl (meth)acrylate and
methylglycidyl (meth)acrylate; cyano group-containing monomers such
as acrylonitrile and methacrylonitrile; heterocyclic
ring-containing vinyl monomers such as N-vinyl-2-pyrrolidone,
(meth)acryloylmorpholine, in addition, N-vinylpyridine,
N-vinylpiperidone, N-vinylpyrimidine, N-vinylpiperazine,
N-vinylpyrrole, N-vinylimidazole, and N-vinyloxazole; alkoxyalkyl
(meth)acrylate-based monomers such as methoxyethyl (meth)acrylate
and ethoxyethyl (meth)acrylate; sulfonic acid group-containing
monomers such as sodium vinylsulfonate; phosphoric acid
group-containing monomers such as 2-hydroxyethyl acryloylphosphate;
imide group-containing monomers such as cyclohexylmaleimide and
isopropylmaleimide; isocyanate group-containing monomers such as
2-methacryloyloxyethyl isocyanate; and the like. As the polar
group-containing monomer, carboxyl group-containing monomers such
as acrylic acid or anhydrides thereof are suitable.
[0032] The amount of the polar group-containing monomer to be used
is 30% by weight or less (e.g., 1 to 30% by weight), preferably 3
to 20% by weight based on the total amount of the monomer
components for forming the acrylic polymer. When the amount of the
polar group-containing monomer to be used exceeds 30% by weight,
for example, there is a concern that the cohesive force of the
acrylic adhesive may become too high and the tackiness of the
adhesive layer may be reduced. Moreover, when the amount of the
polar group-containing monomer to be used is too small (e.g., less
than 1% by weight), the advantageous effects of copolymerization of
these monomers are not obtained in some cases.
[0033] Examples of the polyfunctional monomer include hexanediol
di(meth)acrylate, butanediol di(meth)acrylate, (poly)ethylene
glycol di(meth)acrylate, (poly)propylene glycol di(meth)acrylate,
neopentyl glycol di(meth)acrylate, pentaerythritol
di(meth)acrylate, pentaerythritol tri(meth)acrylate,
dipentaerythritol hexa(meth)acrylate, trimethylolpropane
tri(meth)acrylate, tetramethylolmethane tri(meth)acrylate, allyl
(meth)acrylate, vinyl (meth)acrylate, divinylbenzene, epoxy
acrylate, polyester acrylate, urethane acrylate, and the like.
[0034] The amount of the polyfunctional monomer to be used is 2% by
weight or less (e.g., 0.01 to 2% by weight), preferably 0.02 to 1%
by weight based on the total amount of the monomer components for
forming the acrylic polymer. When the amount of the polyfunctional
monomer to be used exceeds 2% by weight, for example, there is a
concern that the cohesive force of the adhesive may become too high
and the tackiness of the adhesive layer may be reduced. Moreover,
when the amount of the polyfunctional monomer to be used is too
small (e.g., less than 0.01% by weight), the advantageous effects
of copolymerization of these monomers are not obtained in some
cases.
[0035] In addition, examples of the copolymerizable monomers other
than the polar group-containing monomers and the polyfunctional
monomers include vinyl esters such as vinyl acetate and vinyl
propionate, aromatic vinyl compounds such as styrene and
vinyltoluene, and olefins or dienes such as ethylene, butadiene,
isoprene, and isobutylene; vinyl ethers such as vinyl alkyl ether;
vinyl chloride; and the like.
[0036] The rubber-based polymer is not particularly limited and
examples thereof include synthetic rubbers such as diene-based
synthetic rubbers (e.g., isoprene rubber, styrene-isoprene rubber,
butadiene rubber, styrene-butadiene rubber, chloroprene rubber,
etc.) and non-diene-based synthetic rubbers (e.g., butyl rubber,
isobutylene rubber, ethylene propylene rubber, urethane rubber,
silicone rubber, etc.), natural rubber, and the like.
[0037] Further, as polymers for a rubber modifiers, for example,
there may be used polymers having low polarity such as aliphatic
hydrocarbon resins such as 1,3-pentadiene-based polymers and
polybutene, dicyclopentadiene-based alicyclic hydrocarbon resins,
petroleum softeners (paraffinic oil, naphthenic oil, and aromatic
oil).
[0038] In the case where the adhesive composition contains a
polymerization initiator, a curing reaction by heat or an active
energy ray using a polymerization initiator such as a thermal
polymerization initiator or a photopolymerization initiator
(photoinitiator) can be utilized. The polymerization initiator can
be used alone, or two or more kinds can be used in combination.
[0039] Examples of the thermal polymerization initiator include azo
polymerization initiators [e.g., 2,2'-azobisisobutyronitrile,
2,2'-azobis-2-methylbutyronitrile, dimethyl
2,2'-azobis(2-methylpropionate), 4,4'-azobis-4-cyanovaleric acid,
azobisisovaleronitrile, 2,2'-azobis(2-amidinopropane)
dihydrochloride, 2,2'-azobis[2-(5-methyl-2-imidazolin-2-yl)propane]
dihydrochloride, 2,2'-azobis(2-methylpropionamidine) disulfate,
2,2'-azobis(N,N'-dimethyleneisobutylamidine) dihydrochloride,
etc.], peroxide-based polymerization initiators (e.g., dibenzoyl
peroxide, tert-butyl permaleate, etc.), redox polymerization
initiators, and the like. The amount of the thermal polymerization
initiator to be used is not particularly limited, and may be in the
range that can be conventionally used as a thermal polymerization
initiator.
[0040] The photopolymerization initiator is not particularly
limited, and there can be used benzoin ether-based
photopolymerization initiators, acetophenone-based
photopolymerization initiators, .alpha.-ketol-based
photopolymerization initiators, aromatic sulfonyl chloride-based
photopolymerization initiators, photoactive oxime-based
photopolymerization initiators, benzoin based photopolymerization
initiators, benzil-based photopolymerization initiators,
benzophenone-based photopolymerization initiators, ketal-based
photopolymerization initiators, thioxanthone-based
photopolymerization initiators, and the like.
[0041] Specifically, examples of the benzoin ether-based
photopolymerization initiators include benzoin methyl ether,
benzoin ethyl ether, benzoin propyl ether, benzoin isopropyl ether,
benzoin isobutyl ether, 2,2-dimethoxy-1,2-diphenylethan-1-one,
anisole methyl ether, and the like. Examples of the
acetophenone-based photopolymerization initiators include
2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone,
1-hydroxycyclohexyl phenyl ketone, 4-phenoxydichloroacetophenone,
4-(t-butyl)dichloroacetophenone, and the like. Examples of the
.alpha.-ketol-based photopolymerization initiators include
2-methyl-2-hydroxypropiophenone,
1-[4-(2-hydroxyethyl)phenyl]-2-methylpropan-1-one, and the like.
Examples of the aromatic sulfonyl chloride-based
photopolymerization initiators include 2-naphthalene sulfonyl
chloride and the like. Examples of the photoactive oxime-based
photopolymerization initiators include
1-phenyl-1,1-propanedione-2-(o-ethoxycarbonyl)-oxime and the
like.
[0042] The benzoin photopolymerization initiators include, for
example, benzoin. The benzil-based photopolymerization initiators
include, for example, benzil and the like. The benzophenone-based
photopolymerization initiators include, for example, benzophenone,
benzoylbenzoic acid, 3,3'-dimethyl-4-methoxybenzophenone,
polyvinylbenzophenone, .alpha.-hydroxycyclohexyl phenyl ketone, and
the like. The ketal-based photopolymerization initiators includes,
for example, benzyl dimethyl ketal and the like. The
thioxanthone-based photopolymerization initiators include, for
example, thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone,
2,4-dimethylthioxanthone, isopropylthioxanthone,
2,4-diisopropylthioxanthone, dodecylthioxanthone, and the like.
[0043] The amount of the photopolymerization initiator to be used
is not particularly limited, and can be selected from the range of,
for example, 0.01 to 5 parts by weight (preferably 0.05 to 3 parts
by weight) based on 100 parts by weight of all the monomer
components for forming the acrylic polymer.
[0044] At the time of activation of the photopolymerization
initiator, irradiation with active energy rays is performed.
Examples of such active energy rays include ionizing radiations
such as alpha rays, beta rays, gamma rays, neutron rays, and
electron rays, ultraviolet rays, and the like. Particularly,
ultraviolet rays are preferable. Further, the irradiation energy of
the active energy rays, the irradiation time thereof, and the like
are not particularly limited as long as the photopolymerization
initiator can be activated to generate the reaction of the monomer
components.
[0045] The content of the base polymer in the adhesive composition
according to the present embodiment is not particularly limited,
but from the viewpoint of the initial adhesive force, based on all
the components of the adhesive composition excluding the solvent,
that is, when the total amount of the components of the adhesive
composition excluding the solvent is regarded as 100% by weight,
the content is preferably 10% by weight or more, more preferably
15% by weight or more, and still more preferably 20% by weight or
more. Further, the content of the base polymer is, from the
viewpoint of containing the water-absorbing material and the
moisture-curable component, preferably 70% by weight or less, more
preferably 60% by weight or less, and still more preferably 50% by
weight or less based on all the components of the adhesive
composition excluding the solvent.
[0046] In the present embodiment, the water-absorbing material
refers to a material capable of absorbing and retaining water. In
the adhesive composition according to the present embodiment, at
the time when the adhesive sheet is pasted to the wet surface of
the adherend, the water-absorbing material absorbs and retains the
water on the wet surface, which interferes with the adhesion
between the adhesive sheet and the adherend, and thereby the
initial adhesive force to the adherend, which is required for the
adhesive sheet, is well exhibited. In addition, since the water on
the wet surface of the adherend is absorbed and removed by the
water-absorbing material, the adhesive sheet can well follow even
to an adherend having an uneven surface.
[0047] As the water-absorbing material, an organic water-absorbing
material such as a water-absorbing polymer or an inorganic
water-absorbing material can be used. As the water-absorbing
material, only one kind may be used alone, or two or more kinds may
be used in combination.
[0048] Examples of the water-absorbing polymer include polyacrylic
acids, water-soluble celluloses, polyvinyl alcohols, polyethylene
oxides, starches, alginic acids, chitins, polysulfonic acids,
polyhydroxymethacrylates, polyvinylpyrrolidones, polyacrylamides,
polyethyleneimines, polyallylamines, polyvinylamines, maleic
anhydrides, copolymers thereof, and the like. As the
water-absorbing polymer, only one kind may be used alone, or two or
more kinds may be used in combination.
[0049] Among them, a polyacrylic acid sodium salt or a copolymer of
maleic anhydride and polyisobutylene is preferable, and a copolymer
of maleic anhydride and polyisobutylene is more preferable.
[0050] A commercially available product may be used as the
water-absorbing polymer. As commercially available products of the
water-absorbing polymers, there can be suitably used, for example,
KC Flock (cellulose powder, manufactured by Nippon Paper Chemicals
Co., Ltd.), Sunrose (carboxymethyl cellulose, manufactured by
Nippon Paper Chemicals, Co., Ltd.), Aqualic CA (acrylic acid
polymer partial sodium salt crosslinked product, manufactured by
Nippon Shokubai Co., Ltd.), Acryhope (acrylic acid polymer partial
sodium salt crosslinked product, manufactured by Nippon Shokubai
Co., Ltd.), Sunwet (polyacrylate salt crosslinked product,
manufactured by San-Dia Polymers, Ltd.), Aqua Pearl (polyacrylate
salt crosslinked product, manufactured by San-Dia Polymers, Ltd.),
Aqua Keep (acrylic acid polymer partial sodium salt crosslinked
product, manufactured by Sumitomo Seika Chemicals Co., Ltd.),
Aquacalk (modified polyalkylene oxide, manufactured by Sumitomo
Seika Chemicals Co., Ltd.), KI gel (isobutylene-maleic anhydride
copolymer crosslinked product, manufactured by Kuraray Co., Ltd.),
and the like.
[0051] Examples of the inorganic water-absorbing material include
silica gel and inorganic polymers such as Sumecton SA manufactured
by Kunimine Industries Co., Ltd.
[0052] The content of the water-absorbing material in the adhesive
composition according to the present embodiment is not particularly
limited, but from the viewpoint of water absorbability and
removability of the water of the adherend, based on all the
components of the adhesive composition excluding the solvent, that
is, when the total amount of the components of the adhesive
composition excluding the solvent is regarded as 100% by weight,
the content is preferably 0.1% by weight or more, more preferably
0.5% by weight or more, and still more preferably 1% by weight or
more. In addition, the content of the water-absorbing material is,
from the viewpoint of adhesive force after moisture curing,
preferably 50% by weight or less, more preferably 40% by weight or
less, and still more preferably 30% by weight or less based on all
the components of the adhesive composition excluding the
solvent.
[0053] In the present embodiment, the moisture-curable component is
a component having a property (moisture curability) that causes a
curing reaction due to the presence of water (water and moisture).
For example, the moisture-curable component includes a resin or a
compound which has, in the molecule, one or more hydrolyzable
reactive groups or functional groups that start the reaction with
water, and which starts curing with water (water or moisture) in
the surroundings such as the air.
[0054] The moisture-curable component to be used in the adhesive
composition of the present embodiment has moisture curability. The
moisture-curable component is contained in the adhesive composition
in an unreacted state. When an adhesive sheet including an adhesive
layer made from the adhesive composition of the present embodiment
is pasted to an adherend, the moisture-curable component itself in
an unreacted state is cured with the water absorbed from the wet
surface or the water such as surrounding water or moisture and
thereby adhesiveness is further improved. Moreover, the
moisture-curable component is preferably a component capable of
chemically bonding to the adherend to which the adhesive sheet is
pasted. In such a case, the adhesiveness is further improved by the
progress of chemical bonding between the moisture-curable component
in an unreacted state and the adherend.
[0055] As the moisture-curable component to be used in the present
embodiment, isocyanate compounds, alkoxysilyl group-containing
polymers, cyanoacrylate-based compounds, urethane-based compounds,
and the like may be mentioned. Among them, isocyanate compounds and
alkoxysilyl group-containing polymers are preferable in view of
compatibility and curing speed. As the moisture-curable component,
only one kind may be used alone, or two or more kinds may be used
in combination.
[0056] An isocyanate compound (isocyanate) is hydrolyzed in the
presence of water to form an amine, and curing is achieved by the
reaction of the isocyanate with the amine to form a urea bond. In
addition, an isocyanate compound can form a chemical bond with a
hydroxyl group, an amino group, a carboxyl group, and the like on
the surface of an adherend.
[0057] As the isocyanate compound, for example, there can be used
one or more selected from toluene diisocyanates such as Polyflex
PR, Polygrout M-2, and Polygrout S-200 manufactured by Daiichi
Kogyo Seiyaku Co., Ltd., Coronate L manufactured by Tosoh
Corporation, and xylylene diisocyanates such as Takenate M-605NE
and Takenate D-120N manufactured by Mitsui Chemicals, Inc.,
hexamethylene diisocyanates such as Takenate M-631N manufactured by
Mitsui Chemicals, Inc., Duranate MFA-75X manufactured by Asahi
Kasei Corporation, and Coronate HL manufactured by Tosoh
Corporation.
[0058] An alkoxysilyl group-containing polymer is hydrolyzed in the
presence of water to form a silanol and is cured through
condensation (crosslinking). In addition, an alkoxysilyl
group-containing polymer can form a strong chemical bond through a
dehydration condensation reaction with a hydroxyl group on the
surface of an adherend.
[0059] As the alkoxysilyl group-containing polymer, for example,
there can be used one or more selected from linear dimethoxy
group-both terminal type ones such as Silyl SAX220 and Silyl
SAT350, linear dimethoxy group-one terminal type ones such as Silyl
SAT145, linear trimethoxy group-both terminal type ones such as
Silyl SAX510 or Silyl SAT580, branched dimethoxy group-terminal
type ones such as Silyl SAT400, and acrylic modified type ones such
as Silyl MA440, Silyl MA903, and Silyl MA904 manufactured by Kaneka
Corporation.
[0060] The content of the moisture-curable component in the
adhesive composition according to the present embodiment is not
particularly limited, but from the viewpoint of obtaining high
adhesive force, based on all the components of the adhesive
composition excluding the solvent, that is, when the total amount
of the components of the adhesive composition excluding the solvent
is regarded as 100% by weight, the content is preferably 0.1% by
weight or more, more preferably 0.2% by weight or more, and still
more preferably 0.4% by weight or more. In addition, the content of
the moisture-curable component is, from the viewpoint of product
life and pot life, preferably 50% by weight or less, more
preferably 45% by weight or less, and still more preferably 40% by
weight or less based on all the components of the adhesive
composition excluding the solvent.
[0061] The adhesive composition according to the present embodiment
may contain a tackifier (tackifying agent) for the purpose of
adjusting the elastic modulus and imparting tackiness at the time
of initial adhesion. Examples of the tackifier include polybutenes,
rosin-based resins, terpene-based resins, petroleum-based resins
(e.g., petroleum-based aliphatic hydrocarbon resins,
petroleum-based aromatic hydrocarbon resins, and petroleum-based
aliphatic/aromatic copolymerized hydrocarbon resins),
petroleum-based alicyclic hydrocarbon resins (hydrogenated ones of
aromatic hydrocarbon resins), etc.), coumarone-based resins, and
the like. From the viewpoint of compatibility, preferred are
petroleum-based resins and rosin-based resins. As the tackifier,
one kind may be used or two or more kinds may be used in
combination.
[0062] The content of the tackifier in the case where it is
contained in the adhesive composition is, from the viewpoint of
decreasing the elastic modulus, based on all the components of the
adhesive composition excluding the solvent, that is, when the total
amount of the components of the adhesive composition excluding the
solvent is regarded as 100% by weight, the content is preferably 1%
by weight or more, and more preferably 5% by weight or more. In
addition, the content of the tackifier is, from the viewpoint of
imparting an appropriate cohesive force to the adhesive, preferably
70% by weight or less, more preferably 65% by weight or less, and
still more preferably 60% by weight or less based on all the
components of the adhesive composition excluding the solvent.
[0063] To the adhesive composition of the present embodiment, in
the ranges where the advantageous effects of the present invention
are not inhibited, additives usually added to an adhesive
composition, such as viscosity modifiers, release modifiers,
plasticizers, softeners, fillers, colorants (pigment, dye, etc.),
antiaging agents, surfactants, leveling agents, antifoaming agents,
light stabilizers, and the like may be further added.
[0064] Examples of the filler include inorganic fillers such as
talc, titanium oxide, calcium oxide, magnesium oxide, zinc oxide,
titanium oxide, calcium carbonate, carbon, silica, clay, mica,
barium sulfate, whiskers, magnesium hydroxide, and the like.
[0065] The content of the filler is, from the viewpoint of rough
surface adhesiveness, preferably 80% by weight or less and more
preferably 70% by weight or less based on all the components of the
adhesive composition excluding the solvent.
[0066] Moreover, various common solvents can be used as a solvent
to be utilized for an adhesive composition. Examples of the
solvents include organic solvents, e.g., esters such as ethyl
acetate and n-butyl acetate; aromatic hydrocarbons such as toluene
and benzene; aliphatic hydrocarbons such as n-hexane and n-heptane;
alicyclic hydrocarbons such as cyclohexane and methylcyclohexane;
ketones such as methyl ethyl ketone and methyl isobutyl ketone; and
the like. The solvents may be used alone, or two or more kinds may
be used in combination.
[0067] In the adhesive composition of the present embodiment, the
elastic modulus (initial elastic modulus) of the adhesive layer
when forming an adhesive layer (before moisture curing) is
preferably 400 kPa or less, more preferably 300 kPa or less, and
still more preferably 200 kPa or less. When the initial elastic
modulus is 400 kPa or less, good followability can be exhibited
even to an adherend having an uneven surface. In addition, the
water absorbency of the water-absorbing material is well exhibited
without inhibiting swelling at the time when the water-absorbing
material absorbs water on the wet surface of the adherend. Further,
in order to form the adhesive layer satisfactorily, the initial
elastic modulus is preferably 0.1 kPa or more, more preferably 0.5
kPa or more, and further preferably 1 kPa or more, and particularly
preferably 10 kPa or more.
[0068] Here, when the adhesive layer is formed, the initial elastic
modulus of the adhesive layer can be calculated from the
stress-strain curve measured when a sample is prepared by making
the adhesive layer into a string shape and is stretched at a speed
of 50 mm/min using a tensile tester (AG-IS manufactured by Shimadzu
Corporation).
[0069] In addition, an adhesive composition according to one
embodiment of the present invention is an adhesive composition
having a 90.degree. peel adhesive force of 5 N/25 mm or more when
it is measured under the following measurement conditions.
Measurement Conditions
[0070] An adhesive layer having a thickness of 150 .mu.m, which is
made of the above-mentioned adhesive composition, is formed on one
side of a substrate having a thickness of 25 .mu.m and a width of
25 mm, which is made of polyethylene terephthalate, to prepare an
adhesive sheet having a width of 25 mm. The adhesive sheet is
crimped to the surface of a slate plate having a moisture content
of 25% by reciprocating a 2 kg roller once, and is subsequently
immersed in water and allowed to stand at 23.degree. C. for 24
hours. Thereafter, the slate plate to which the adhesive sheet has
been pasted is taken out from the water, and 90.degree. peel
adhesive force (N/25 mm) to the slate plate is measured at a
peeling temperature of 23.degree. C. and a peeling speed of 100
mm/min.
[0071] Hereinafter, the measurement conditions of the
above-mentioned 90.degree. peel adhesive force will be described in
more detail.
[0072] First, an adhesive layer having a thickness of 150 .mu.m,
which is composed of an adhesive composition to be measured, is
formed on one side of a substrate having a thickness of 25 .mu.m
and a width of 25 mm, which is made of polyethylene terephthalate
(PET), to prepare an adhesive sheet (test piece) having a width of
25 mm.
[0073] Further, a slate standard plate, a product name "JIS A5430
(FB)" manufactured by Nippon Test Panel Co., Ltd. (hereinafter also
referred to as a slate plate), which has a thickness of 3 mm, a
width of 30 mm, and a length of 125 mm, is prepared. The glossy
surface of this slate plate is used. The slate plate is dried at
130.degree. C. for 1 hour, and the weight of the slate plate at
this point is defined as "weight of slate plate before immersion in
water". Subsequently, in a state where the prepared slate plate is
immersed in water, degassing is performed for 1 hour with an
ultrasonic degassing apparatus (BRANSON 3510 manufactured by Yamato
Scientific Co., Ltd.), allowed to stand overnight, and then taken
out from water. The weight of the slate plate at this point is
defined as "weight of slate plate after immersion in water and
degassing". Thus, a slate plate having a moisture content of 25% (%
by weight) is prepared.
[0074] Here, the moisture content of the slate plate can be
calculated as follows.
Moisture content of slate plate (% by weight)=[{(Weight of slate
plate after immersion in water and degassing)-(Weight of slate
plate before immersion in water)}/(Weight of slate plate before
immersion in water))].times.100
[0075] Subsequently, immediately after the prepared adhesive sheet
(test piece) having a width of 25 mm is crimped and pasted on the
surface (wet surface) of the slate plate having a moisture content
of 25% by reciprocating a 2 kg roller once, the sheet is immersed
in water and allowed to stand at 23.degree. C. for 24 hours.
Thereafter, the slate plate to which the adhesive sheet (test
piece) has been pasted is taken out from the water, and 90.degree.
peel adhesive force (N/25 mm) at a peeling temperature of
23.degree. C. and a peeling speed of 100 mm/min to the slate plate
is measured using a tensile tester (Technograph TG-1kN manufactured
by Minebea Inc.).
[0076] The above-mentioned 90.degree. peel adhesive force is
preferably 5 N/25 mm or more, more preferably 6 N/25 mm or more,
and still more preferably 8 N/25 mm or more. When the 90.degree.
peel adhesive force is 5 N/25 mm or less, the adhesive force may be
low. Therefore, after the adhesive is pasted to an adherend, there
is a possibility that water and air bubbles that have infiltrated
from the adherend side may generate a gap between the adherend and
the adhesive until moisture curing in water is completed and also
the adhesive may peel off the adherend.
[0077] In addition, an adhesive composition according to one
embodiment of the present invention is an adhesive composition
having a 90.degree. peel adhesive force of 5 N/25 mm or more when
measured under the following measurement conditions.
Measurement Conditions
[0078] An adhesive layer having a thickness of 150 .mu.m, which is
made of the above-mentioned adhesive composition, is formed on one
side of a substrate having a thickness of 25 .mu.m and a width of
25 mm, which is made of polyethylene terephthalate, to prepare an
adhesive sheet having a width of 25 mm. After the sheet is crimped
to the surface of a slate plate having a moisture content of 12% by
reciprocating a 2 kg roller once, the sheet is immersed in water
and allowed to stand at 23.degree. C. for 24 hours. Thereafter, the
slate plate to which the adhesive sheet has been pasted is taken
out from the water, and 90.degree. peel adhesive force (N/25 mm) at
a peeling temperature of 23.degree. C. and a peeling speed of 100
mm/min to the slate plate is measured.
[0079] Hereinafter, the measurement conditions of the
above-mentioned 90.degree. peel adhesive force will be described in
more detail.
[0080] First, an adhesive layer having a thickness of 150 .mu.m,
which is composed of an adhesive composition to be measured, is
formed on one side of a substrate having a thickness of 25 .mu.m
and a width of 25 mm, which is made of polyethylene terephthalate
(PET), to prepare an adhesive sheet (test piece) having a width of
25 mm.
[0081] Further, a slate standard plate, a product name "JIS A5430
(FB)" manufactured by Nippon Test Panel Co., Ltd. (hereinafter also
referred to as a slate plate), which has a thickness of 3 mm, a
width of 30 mm, and a length of 125 mm, is prepared. The glossy
surface of this slate plate is used. The weight of the slate plate
at this point is defined as "weight of slate plate before immersion
in water". Subsequently, in a state where the prepared slate plate
is immersed in water, degassing is performed for 1 hour with an
ultrasonic degassing apparatus (BRANSON 3510 manufactured by Yamato
Scientific Co., Ltd.), allowed to stand overnight, and then taken
out from water. The weight of the slate plate at this point is
defined as "weight of slate plate after immersion in water and
degassing". Thus, a slate plate having a moisture content of 12% (%
by weight) is prepared.
[0082] Here, the moisture content of the slate plate can be
calculated as follows.
Moisture content of slate plate (% by weight)=[{(Weight of slate
plate after immersion in water and degassing)-(Weight of slate
plate before immersion in water)}/(Weight of slate plate before
immersion in water))].times.100
[0083] Subsequently, immediately after the prepared adhesive sheet
(test piece) having a width of 25 mm is crimped and pasted on the
surface (wet surface) of the slate plate having a moisture content
of 12% by reciprocating a 2 kg roller once, the sheet is immersed
in water and allowed to stand at 23.degree. C. for 24 hours.
Thereafter, the slate plate to which the adhesive sheet (test
piece) has been pasted is taken out from the water, and 90.degree.
peel adhesive force (N/25 mm) at a peeling temperature of
23.degree. C. and a peeling speed of 100 mm/min to the slate plate
is measured using a tensile tester (Technograph TG-1kN manufactured
by Minebea Inc.).
[0084] The above-mentioned 90.degree. peel adhesive force is
preferably 5 N/25 mm or more, more preferably 6 N/25 mm or more,
and still more preferably 8 N/25 mm or more. When the 90.degree.
peel adhesive force is 5 N/25 mm or less, the adhesive force may be
low. Therefore, after the adhesive is pasted to an adherend, there
is a possibility that water and air bubbles that have infiltrated
from the adherend side may generate a gap between the adherend and
the adhesive until moisture curing in water is completed and also
the adhesive may peel off the adherend.
[0085] An adhesive layer of the present embodiment is formed using
the above-mentioned adhesive composition. The formation method
thereof is not particularly limited, but a known method can be
adopted, and the formation can be performed in accordance with the
following method for producing the adhesive sheet. Incidentally,
the preferable range of the amount of each component in the
adhesive layer is the same as the preferable range of the amount of
each component of the adhesive composition excluding the
solvent.
[0086] The adhesive layer can be obtained, for example, in the form
of an adhesive sheet by applying the adhesive composition to a
substrate to be mentioned later using a known coating method and
drying the composition. Moreover, after the adhesive composition is
applied to a surface having releasability and dried or cured to
thereby form an adhesive layer on the surface, the adhesive layer
may be pasted to a non-releasable substrate and then transferred
thereto. The method for applying the adhesive composition to the
substrate is not particularly limited, and the application can be
performed using, for example, a gravure roll coater, a reverse roll
coater, a kiss roll coater, a dip roll coater, a bar coater, a
knife coater, a spray coater, a fountain die coater, a closed edge
die coater, or the like. In addition, a solvent-less coating method
such as kneading-extrusion coating may be applied.
[0087] Further, the adhesive layer may be formed by applying the
adhesive composition on a release sheet (which may be a sheet-like
substrate provided with a release surface).
[0088] The thickness of the adhesive layer after drying is not
particularly limited, but is preferably 5 to 1000 .mu.m, and more
preferably 10 to 500 .mu.m from the viewpoint of exhibiting good
followability to an adherend having an uneven surface. The drying
temperature may be, for example, 50 to 150.degree. C.
[0089] At the surface of the adhesive layer to be pasted to the
adherend (pasting surface), the water-absorbing material is exposed
at preferably 0.5 to 80% (more preferably 1 to 70%) of the surface
area of the pasting surface. When the ratio of the water-absorbing
material to the surface area of the pasting surface of the adhesive
layer is 0.5% or more, the water on the wet surface of the adherend
can be absorbed well. Moreover, when the ratio of the
water-absorbing material to the surface area of the pasting surface
of the adhesive layer is 80% or less, the adhesive layer can be
well adhered to the adherend.
[0090] An adhesive sheet of the present embodiment includes the
above-described adhesive layer.
[0091] The adhesive sheet of the present embodiment may be an
adhesive sheet with a substrate in a form having an adhesive layer
on one side or both sides of a sheet-like substrate (support), or
may be a substrate-less adhesive sheet in a form where the adhesive
layer is held by a release sheet. The concept of the adhesive sheet
as referred to herein may include those referred to as an adhesive
tape, an adhesive label, an adhesive film, and the like.
[0092] Incidentally, the adhesive layer is typically formed
continuously, but is not limited to such a form, and may be, for
example, an adhesive layer formed in a regular or random pattern,
such as dot-like or stripe-like one. Further, the adhesive sheet of
the present embodiment may be roll-shaped one or sheet-shaped one.
Alternatively, it may be an adhesive sheet in a form where it is
further processed into various shapes.
[0093] Examples of the material that forms the substrate include
polyolefin-based films of polyethylene, polypropylene,
ethylene/propylene copolymer, and the like; polyester-based films
of polyethylene terephthalate and the like; plastic films of
polyvinyl chloride and the like; and paper such as kraft paper and
Japanese paper; cloths such as cotton cloth and Sufu (spun rayon)
cloth; nonwoven fabrics such as polyester nonwoven fabric and
vinylon nonwoven fabric; and metal foils. Also, the thickness of
the substrate is not particularly limited.
[0094] The plastic films may be unstretched films or stretched
(uniaxially stretched or biaxial stretched) films. In addition, the
surface of the substrate on which the adhesive layer is provided
may be subjected to surface treatment such as application of a
primer, corona discharge treatment, or the like.
[0095] In the present embodiment, the adhesive sheet may be
perforated to provide a through hole. In this way, at the time when
the adhesive sheet is attached to an adherend, since water on the
wet surface of the adherend can be released to the back side
(opposite to the pasted surface) of the adhesive sheet through the
through hole, more water on the wet surface of the adherend can be
removed.
[0096] In the adhesive sheet of the present embodiment, the
adhesive layer may be protected with a release liner (separator,
release film) until the time of use. In addition, the protection
with the release liner is also useful for maintaining the unreacted
state of the unreacted moisture-curable component in the adhesive
composition (adhesive layer).
[0097] As the release liner, a conventional release paper or the
like can be used, and is not particularly limited. For example, a
substrate having a release-treated layer, a low adhesive substrate
composed of a fluorine-based polymer, a low adhesive substrate
composed of a nonpolar polymer, or the like can be used. Examples
of the substrate having a release-treated layer include plastic
films, paper, and the like which have been surface-treated with a
release treatment agent such as silicone-based one, long chain
alkyl-based one, fluorine-based one, or molybdenum sulfide.
Examples of the fluorine-based polymer of the low adhesive
substrate composed of a fluorine-based polymer include
polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinyl
fluoride, polyvinylidene fluoride,
tetrafluoroethylene-hexafluoropropylene copolymer,
chlorofluoroethylene-vinylidene fluoride copolymer, and the like.
Examples of the nonpolar polymer of the low-adhesive substrate
composed of a nonpolar polymer include olefin-based resins (e.g.,
polyethylene, polypropylene, etc.), and the like. Incidentally, the
release liner can be formed by a known or conventional method. In
addition, the thickness and the like of the release liner are not
particularly limited.
[0098] In the adhesive composition according to the present
embodiment, the adhesive layer made from the adhesive composition,
or the adhesive sheet including the adhesive layer, the
moisture-curable component is contained in an unreacted state.
Here, the unreacted state indicates a state where a curing reaction
is not generated by water (water or moisture). In the present
embodiment, all of the moisture-curable component is preferably in
an unreacted state, but a part of the moisture-curable component
may be in a reacted state as long as the advantageous effects of
the present invention are exhibited. This case is also included in
the case where the moisture-curable component in the present
embodiment is contained in an unreacted state.
[0099] The ratio (unreacted ratio) of the unreacted
moisture-curable component in the adhesive composition of the
moisture curing component can be measured as follows, for example,
in the case of using an isocyanate compound as the moisture-curable
component.
[0100] First, the ratio of the absorbance at 2275 cm.sup.-1 derived
from the isocyanate group and the absorbance at 2250-2255 cm.sup.-1
derived from the methylene group of the base polymer obtained from
the infrared spectroscopic measurement of the adhesive sheet
(adhesive layer) immediately after the preparation is calculated.
Here, the absorbance ratio is the ratio of the absorbance derived
from the above-mentioned isocyanate group to the absorbance derived
from the above-mentioned methylene group (the absorbance derived
from the isocyanate group/the absorbance derived from the methylene
group). In addition, the absorbance ratio obtained from the
infrared spectroscopic measurement of the adhesive sheet (adhesive
layer) immediately before pasting is similarly calculated, and the
unreacted ratio of the moisture-curable component (isocyanate
compound) is calculated from the change ratio thereof.
Specifically, it is calculated from the following relational
expression.
Unreacted ratio of moisture-curable component (isocyanate compound)
(%)={(Absorbance ratio of adhesive sheet immediately before
pasting)/(Absorbance ratio of adhesive sheet immediately after
preparation)}.times.100
[0101] When an isocyanate compound is used as the moisture-curable
component, depending on the combination of the isocyanate compound
and the base polymer, the base polymer may be previously
crosslinked with a part of the isocyanate compound. In such a
manner, the adhesive force can be improved in some cases.
[0102] With regard to the adhesive composition, the adhesive layer,
and the adhesive sheet (adhesive composition and the like) of the
present embodiment, in order to maintain the unreacted state of the
unreacted moisture-curable component in the adhesive composition
and the like, it is preferable to reduce or block the influence of
surrounding water (water component and moisture). For example, the
adhesive sheet of the present embodiment may be packaged in a
suitable package. Examples of the material of the package include
an aluminum-made moisture-proof bag and the like, but the material
is not limited thereto. Further, the atmosphere inside the package
may be the air, but may be replaced by an inert gas such as
nitrogen or argon. In addition, a desiccant such as silica gel may
be also packaged inside the package.
[0103] An adherend to which the adhesive sheet of the present
embodiment is to be pasted is not particularly limited, but one
capable of chemically bonding to the moisture-curable component in
an unreacted state in the adhesive composition (adhesive layer) is
preferable. For example, in addition to concrete, mortar, asphalt,
metal, wood, tiles, and plastic materials such as a coated surface
and inner wall of a bathroom, skin, bone, teeth, inside of a living
body, and the like may be mentioned.
EXAMPLES
[0104] Hereinafter, embodiments of the present invention will be
described in more detail using Examples.
Examples 1 to 6 and Comparative Examples 1 to 3
Preparation of Adhesive Sheet
Example 1
[0105] A solution of a copolymer (acrylic polymer 1) of 98 parts by
weight of 2-ethylhexyl acrylate and 2 parts by weight of acrylic
acid diluted with ethyl acetate as a solvent was prepared.
[0106] Into the solution of this acrylic polymer 1 were blended an
isocyanate compound in an unreacted state (TAKENATE M-631N
manufactured by Mitsui Chemicals, Inc.) as a moisture-curable
component, a water-absorbing material (KI-GEL 201K-F2 manufactured
by Kuraray Trading Co., Ltd.), and a tackifier (liquid completely
hydrogenated rosin methyl ester resin, M-HDR manufactured by
Maruzen Petrochemical Co., Ltd.) so that the proportions of the
respective components relative to the total amount of the
components of the adhesive composition excluding the solvent might
become the proportions described in Table 1, and thereby a coating
liquid of the adhesive composition was prepared.
[0107] As a release liner, a polyester-made release film (trade
name "Diafoil MRF", thickness of 38 .mu.m, manufactured by
Mitsubishi Polyester Corporation) having a release surface
subjected to release treatment on one side was prepared. The
coating liquid of the adhesive composition was applied to the
release surface of the release liner, dried at 80.degree. C. for 5
minutes, and then further dried at 130.degree. C. for 30 minutes to
form an adhesive layer having a thickness of 150 .mu.m. The other
surface of the adhesive layer formed on the above release liner was
pasted to a substrate film having a thickness of 25 .mu.m to
produce a single-sided adhesive sheet. As the substrate film, a PET
film (resin film) manufactured by Toray Industries, Inc., a trade
name "Lumirror S-10" was used. The adhesive sheet produced in this
manner was cut to be a size of a width of 25 mm and a length of 10
cm, and 90.degree. peel adhesive force measurement to be mentioned
later was performed. Incidentally, in order to maintain the
unreacted state of the moisture-curable component, the adhesive
sheet produced in Example 1 was sealed together with silica gel in
a moisture-proof bag made of aluminum until the adhesive force
measurement to be mentioned later.
[0108] The same adhesive sheet as described above may be also
formed by applying and drying the coating the adhesive composition
to a PET film so that the thickness after drying be 150 .mu.m to
form an adhesive layer and subsequently laminating a release liner
on the adhesive layer.
Example 2
[0109] An adhesive sheet of Example 2 was produced in the same
manner as in Example 1 except that an isocyanate compound in an
unreacted state (Takenate D120 manufactured by Mitsui Chemicals,
Inc.) was used as a moisture-curable component and the blending
ratio was changed so that the proportions of the respective
components relative to the total amount of the components of the
adhesive composition excluding the solvent might become the
proportions described in Table 1. Incidentally, in order to
maintain the unreacted state of the moisture-curable component, the
adhesive sheet produced in Example 2 was sealed together with
silica gel in a moisture-proof bag made of aluminum until the
adhesive force measurement to be mentioned later.
Example 3
[0110] An adhesive sheet of Example 3 was produced in the same
manner as in Example 1 except that an isocyanate compound in an
unreacted state (Coronate HL manufactured by Tosoh Corporation) was
used as a moisture-curable component and the blending ratio was
changed so that the proportions of the respective components
relative to the total amount of the components of the adhesive
composition excluding the solvent might become the proportions
described in Table 1. Incidentally, in order to maintain the
unreacted state of the moisture-curable component, the adhesive
sheet produced in Example 3 was sealed together with silica gel in
a moisture-proof bag made of aluminum until the adhesive force
measurement to be mentioned later.
Example 4
[0111] An adhesive sheet of Example 4 was produced in the same
manner as in Example 1 except that an isocyanate compound in an
unreacted state (Duranate MFA-75 manufactured by Asahi Kasei
Corporation) was used as a moisture-curable component and the
blending ratio was changed so that the proportions of the
respective components relative to the total amount of the
components of the adhesive composition excluding the solvent might
become the proportions described in Table 1. Incidentally, in order
to maintain the unreacted state of the moisture-curable component,
the adhesive sheet produced in Example 4 was sealed together with
silica gel in a moisture-proof bag made of aluminum until the
adhesive force measurement to be mentioned later.
Example 5
[0112] An adhesive sheet of Example 5 was produced in the same
manner as in Example 1 except that an isocyanate compound in an
unreacted state (Coronate L manufactured by Tosoh Corporation) was
used as a moisture-curable component and the blending ratio was
changed so that the proportions of the respective components
relative to the total amount of the components of the adhesive
composition excluding the solvent might become the proportions
described in Table 1. Incidentally, in order to maintain the
unreacted state of the moisture-curable component, the adhesive
sheet produced in Example 5 was sealed together with silica gel in
a moisture-proof bag made of aluminum until the adhesive force
measurement to be mentioned later.
Example 6
[0113] An adhesive sheet of Example 6 was produced in the same
manner as in Example 1 except that a solution containing an acrylic
polymer 2 in which a copolymer of 100 parts by weight of butyl
acrylate and 5 parts by weight of acrylic acid was diluted with
ethyl acetate as a solvent was prepared as a solution containing a
base polymer, an alkoxysilyl group-containing polymer in an
unreacted state (Silyl SAX510 and Silyl SAT145 manufactured by
Kaneka Corporation) and an isocyanate compound in an unreacted
state (Coronate L manufactured by Tosoh Corporation) were used as
moisture-curable components, Haritack PCJ (polymerized rosin ester,
manufactured by Harima Chemicals, Inc.) was used as a tackifier,
and the blending ratio was changed so that the proportions of the
respective components relative to the total amount of the
components of the adhesive composition excluding the solvent might
become the proportions described in Table 1. Incidentally, in order
to maintain the unreacted state of the moisture-curable component,
the adhesive sheet produced in Example 6 was sealed together with
silica gel in a moisture-proof bag made of aluminum until the
adhesive force measurement to be mentioned later.
Comparative Example 1
[0114] A solution of an acrylic polymer 2 of 100 parts by weight of
butyl acrylate and 5 parts by weight of acrylic acid diluted with
ethyl acetate as a solvent was prepared as a solution containing a
base polymer.
[0115] Into the solution was blended an isocyanate compound in an
unreacted state (Coronate L manufactured by Tosoh Corporation) as a
moisture-curable component so that the proportions of respective
components relative to the total amount of the components of the
adhesive composition excluding the solvent might become the
proportions described in Table 1, and thereby a coating liquid of
the adhesive composition was prepared. Incidentally, in the
adhesive composition of the present Comparative Example, a
water-absorbing material and a tackifier were not used.
[0116] As a release liner, a polyester-made release film (trade
name "Diafoil MRF", thickness of 38 .mu.m, manufactured by
Mitsubishi Polyester Corporation) having a release surface
subjected to release treatment on one side was prepared. The
coating liquid of the adhesive composition was applied to the
release surface of the release liner, dried at 80.degree. C. for 5
minutes, and then further dried at 130.degree. C. for 30 minutes to
form an adhesive layer having a thickness of 150 .mu.m. The other
surface of the adhesive layer formed on the above release liner was
pasted to a substrate film having a thickness of 25 .mu.m to
produce a single-sided adhesive sheet. As the substrate film, a PET
film (resin film) manufactured by Toray Industries, Inc., a trade
name "Lumirror S-10" was used. The adhesive sheet produced in this
manner was cut to be a size of a width of 25 mm and a length of 10
cm. Furthermore, the produced adhesive sheet was aged for 48 hours
under an environment of 40.degree. C./90% RH without moisture-proof
packaging and thereby all the moisture-curable components in the
adhesive composition (adhesive layer) were brought into a reacted
state. Thereafter, 90.degree. peel adhesive force measurement to be
mentioned later was performed.
Comparative Example 2
[0117] An adhesive sheet of Comparative Example 2 was produced in
the same manner as in Example 1 except that an isocyanate compound
in an unreacted state (Takenate M-631 manufactured by Mitsui
Chemicals, Inc.) was used as a moisture-curable component and the
blending ratio was changed so that the proportions of the
respective components relative to the total amount of the
components of the adhesive composition excluding the solvent might
become the proportions described in Table 1. Furthermore, the
produced adhesive sheet was aged for 48 hours under an environment
of 40.degree. C./90% RH without moisture-proof packaging and
thereby all the moisture-curable components in the adhesive
composition (adhesive layer) were brought into a reacted state.
Thereafter, 90.degree. peel adhesive force measurement to be
mentioned later was performed.
Comparative Example 3
[0118] An adhesive sheet of Comparative Example 3 was produced in
the same manner as in Example 1 except that an isocyanate compound
in an unreacted state (Takenate M-631 manufactured by Mitsui
Chemicals, Inc.) was used as a moisture-curable component and the
blending ratio was changed so that the proportions of the
respective components relative to the total amount of the
components of the adhesive composition excluding the solvent might
become the proportions described in Table 1. Incidentally, in the
adhesive composition of the present Comparative Example, a
water-absorbing material was not used. In addition, in order to
maintain the unreacted state of the moisture-curable component, the
adhesive sheet produced in Comparative Example 3 was sealed
together with silica gel in a moisture-proof bag made of aluminum
until the adhesive force measurement to be mentioned later.
Measurement of 90.degree. Peel Adhesive Force to Wet
Surface>
[0119] A slate standard plate, a product name "JIS A5430 (FB)"
manufactured by Nippon Test Panel Co., Ltd. (hereinafter also
referred to as a slate plate), which had a thickness of 3 mm, a
width of 30 mm, and a length of 125 mm, was prepared. The glossy
surface of this slate plate was used. The weight of the slate plate
was measured and defined as "weight of slate plate before immersion
in water".
[0120] Subsequently, in a state where the prepared slate plate was
immersed in water, degassing was performed for 1 hour with an
ultrasonic degassing apparatus (BRANSON 3510 manufactured by Yamato
Scientific Co., Ltd.), allowed to stand overnight, and then taken
out from water. The weight of the slate plate at this point was
measured and defined as "weight of slate plate after immersion in
water and degassing".
[0121] When the moisture content of the slate plate was calculated
from the following expression based on the measured "weight of the
slate plate before immersion in water" and "weight of the slate
plate after immersion in water and degassing", the content was 12%
(% by weight).
Moisture content of slate plate (% by weight)=[{(Weight of slate
plate after immersion in water and degassing)-(Weight of slate
plate before immersion in water)}/(Weight of slate plate before
immersion in water))].times.100
[0122] Subsequently, immediately after an adhesive sheet (test
piece) from which the release liner had been peeled off was crimped
and pasted on the surface (wet surface) of the slate plate having a
moisture content of 12% by reciprocating a 2 kg roller once, the
sheet was immersed in water and allowed to stand at 23.degree. C.
for 24 hours. Thereafter, the slate plate to which the adhesive
sheet (test piece) had been pasted was taken out from the water,
and 90.degree. peel adhesive force (N/25 mm) at a peeling
temperature of 23.degree. C. and a peeling speed of 100 mm/min to
the slate plate was measured using a tensile tester (Technograph
TG-1kN manufactured by Minebea Inc.). Table 1 shows results
thereof.
[0123] Incidentally, when the measured value of the 90.degree. peel
adhesive force (N/25 mm) is 5N/25 mm or more, the adhesive force to
the wet surface can be evaluated high.
Measurement of Initial Elastic Modulus)
[0124] A sample was prepared by making an adhesive layer made from
the adhesive composition into a string shape, and for this sample,
using a tensile tester (AG-IS manufactured by Shimadzu
Corporation), the initial elastic modulus of the adhesive layer was
calculated from the stress-strain curve measured when the sample
was stretched at a rate of 50 mm/min. More specifically, it was
calculated by the following method. Table 1 shows results
thereof.
[0125] As a release liner, a polyester-made release film (trade
name "Diafoil MRF", thickness of 38 .mu.m, manufactured by
Mitsubishi Polyester Corporation) having a release surface
subjected to release treatment on one side was prepared. A coating
liquid of the adhesive composition was applied to the release
surface of the release liner, dried at 70.degree. C. for 5 minutes,
and then dried at 120.degree. C. for 10 minutes to form an adhesive
layer having a thickness of 150 .mu.m. The other side of the
polymer layer formed on the above release liner was pasted to the
release surface of the same release liner as the release liner that
had already been pasted, and thus a sheet of the adhesive layer
whose both surfaces were protected with the release liners was
produced.
[0126] The resulting sheet of the adhesive layer was cut into a
size of a width of 30 mm and a length of 20 mm, and only the
adhesive layer was rolled in the longitudinal direction to form a
string shape and thus a sample having an initial cross-sectional
area of 3 mm.sup.2 was formed. The initial elastic modulus thereof
was calculated from a stress-strain curve measured when the sample
was set at an initial length of 10 mm and then stretched at a
tensile rate of 50 mm/min using a tensile tester (AG-IS
manufactured by Shimadzu Corporation).
TABLE-US-00001 TABLE 1 Adhesive composition 90.degree. peel Initial
Reaction state of Water-absorbing Tackifier Filler adhesive elastic
Base polymer Moisture-curable component moisture-curable material
(% by (% by force modulus (% by weight) (% by weight) component (%
by weight) weight) weight) (N/25 mm) (kPa) Example 1 Acrylic
polymer 1 Takenate M-631N Unreacted state KI gel M-HDR -- 18.3 8.7
37.3 2.3 23.1 37.3 -- Example 2 Acrylic polymer 1 Takenate D120
Unreacted state KI gel M-HDR -- 19.3 4.9 38.0 0.95 23.1 38.0 --
Example 3 Acrylic polymer 1 Coronate HL Unreacted state KI gel
M-HDR -- 18.8 4.8 38.0 0.84 23.1 38.0 -- Example 4 Acrylic polymer
1 Duranate MFA-75 Unreacted state KI gel M-HDR -- 20.0 9.0 38.1
0.76 23.1 38.1 Example 5 Acrylic polymer 1 Coronate L Unreacted
state KI gel M-HDR -- 9.8 0.6 38.1 0.76 23.1 38.1 Example 6 Acrylic
polymer 2 SAX510 SAT145 Coronate L Unreacted state KI gel Haritack
PCJ -- 21.8 14.9 39.8 13.9 6.0 0.4 24.0 15.9 Comparative Acrylic
polymer 2 Coronate L Reacted state -- -- -- 0.3 36.4 Example 1 99.0
1.0 -- -- -- Comparative Acrylic polymer 1 Takenate M-631 Reacted
state KI gel M-HDR -- 0.4 58.9 Example 2 37.3 2.3 23.1 37.3 --
Comparative Acrylic polymer 1 Takenate M-631 Unreacted state --
M-HDR -- 3.9 5.3 Example 3 48.5 3.0 -- 48.5 --
[0127] In the adhesive sheet of Comparative Example 1 in which the
moisture-curable component in the adhesive composition (adhesive
layer) was in a reacted state before pasting and the
water-absorbing material was not contained in the adhesive
composition (adhesive layer), the 90.degree. peel adhesive force
measured by the above measurement test was as low as 0.3 N/25
mm
[0128] Further, in the adhesive sheet of Comparative Example 2 in
which the moisture-curable component in the adhesive composition
(adhesive layer) was in a reacted state before pasting, the
90.degree. peel adhesive force measured by the above measurement
test was as low as 0.4 N/25 mm
[0129] Moreover, in the adhesive sheet of Comparative Example 3 in
which the water-absorbing material was not contained in the
adhesive composition (adhesive layer), the 90.degree. peel adhesive
force measured by the above measurement test was as low as 3.9 N/25
mm.
[0130] On the other hand, in the adhesive sheets of Example 1-6,
the 90.degree. peel adhesive force measured by the above-mentioned
measurement test was all 5 N/25 mm or more, and the sheets had high
adhesive force to the wet surface.
[0131] Incidentally, for the adhesive sheet of Example 5, when
90.degree. peel adhesive force (N/25 mm) was measured according to
the same procedure as the above-described measurement test after
the sheet was subjected to moisture-proof packaging and then aged
at ordinary temperature for 30 days, it was confirmed that the
adhesive force was improved to be as high as 13.1 N/25 mm, as
compared with the 90.degree. peel adhesive force (N/25 mm) before
aging. In addition, from the measurement result of the reaction
ratio of the isocyanate compound, it was confirmed separately that
a part of the isocyanate compound in the adhesive composition
(adhesive layer) in the adhesive sheet after aging for 30 days was
in an unreacted state.
[0132] Moreover, for the adhesive layer made from the adhesive
composition of Example 5, when an elastic modulus was measured
after the layer was subjected to moisture-proof packaging and then
aged at ordinary temperature for 30 days, the elastic modulus was
14.9 kPa.
[0133] It is considered that the water contained in the adhesive
has promoted the moisture curing reaction of the isocyanate
compound, but the elastic modulus is within a preferable range for
wet adhesion and a part of isocyanate compounds in an unreacted
state are present, and hence a wet adhesion effect is obtained.
Example 7 to 9
Preparation of Adhesive Sheet
Example 7
[0134] A high-molecular-weight polyisobutylene polymer (Opanol N80
manufactured by BASF, hereinafter also referred to as rubber-based
polymer 1), a low-molecular-weight polyisobutylene polymer (Tetrax
5T manufactured by JXTG Energy Corporation, hereinafter also
referred to as rubber-based polymer 2), and liquid polybutene
(HV-300 manufactured by JXTG Energy Corporation, rubber-modifying
component) as a base polymer were dissolved in toluene as a
solvent.
[0135] Into this solution, hexamethylene diisocyanate (HDI) in an
unreacted state (Basonat HA2000 manufactured by BASF SE) as a
moisture-curable component, a water-absorbing material (KI gel
201K-F2 manufactured by Kuraray Trading Co., Ltd.), a tackifier
(petroleum resin, Escollets 1202U manufactured by EMG Marketing
G.K.), and heavy calcium carbonate (manufactured by Maruo Calcium
Co., Ltd.) as a filler were blended so that the proportions of
respective components relative to the total amount of the
components excluding the solvent of the adhesive composition might
become the proportions described in Table 2, thereby producing a
coating liquid of the adhesive composition.
[0136] As a release liner, a polyester-made release film (trade
name "Diafoil MRF", thickness of 38 .mu.m, manufactured by
Mitsubishi Polyester Corporation) having a release surface
subjected to release treatment on one side was prepared. The
coating liquid of the adhesive composition was applied to the
release surface of the release liner, dried at 80.degree. C. for 5
minutes, and further dried at 130.degree. C. for 30 minutes to form
an adhesive layer having a thickness of 150 .mu.m. The other
surface of the adhesive layer formed on the above release liner was
pasted to a substrate film having a thickness of 25 .mu.m to
produce a single-sided adhesive sheet. As the substrate film, a PET
film (resin film) manufactured by Toray Industries, Inc., a trade
name "Lumirror S-10" was used. The adhesive sheet produced in this
manner was cut into a size of a width of 25 mm and a length of 10
cm, and 90.degree. peel adhesive force measurement to be mentioned
later was performed.
[0137] Incidentally, in order to maintain the non-reacted state of
the moisture-curable component, the adhesive sheet produced in
Example 7 was sealed together with silica gel in a moisture-proof
bag made of aluminum until the adhesive force measurement to be
mentioned later.
Example 8
[0138] An adhesive sheet of Example 8 was produced in the same
manner as in Example 7 except that the blending ratio was changed
so that the proportions of the respective components relative to
the total amount of the components of the adhesive composition
excluding the solvent might become the proportions described in
Table 2. Incidentally, in order to maintain the unreacted state of
the moisture-curable component, the adhesive sheet produced in
Example 8 was sealed together with silica gel in a moisture-proof
bag made of aluminum until the adhesive force measurement to be
mentioned later.
Example 9
[0139] An adhesive sheet of Example 9 was produced in the same
manner as in Example 7 except that a rubber-based polymer-1 was
used as a base polymer and the blending ratio was changed so that
the proportions of the respective components relative to the total
amount of the components of the adhesive composition excluding the
solvent might become the proportions described in Table 2.
Incidentally, in order to maintain the unreacted state of the
moisture-curable component, the adhesive sheet produced in Example
9 was sealed together with silica gel in a moisture-proof bag made
of aluminum until the adhesive force measurement to be mentioned
later.
Measurement of 90.degree. Peel Adhesive Force to Wet Surface
[0140] A slate standard plate, a product name "JIS A5430 (FB)"
manufactured by Nippon Test Panel Co., Ltd. (hereinafter also
referred to as slate plate), which had a thickness of 3 mm, a width
of 30 mm, and a length of 125 mm, was prepared. The glossy surface
of this slate plate was used. The slate plate is dried at
130.degree. C. for 1 hour, and the weight of the slate plate was
measured and defined as "weight of slate plate before immersion in
water".
[0141] Subsequently, in a state where the prepared slate plate was
immersed in water, degassing was performed for 1 hour with an
ultrasonic degassing apparatus (BRANSON 3510 manufactured by Yamato
Scientific Co., Ltd.), allowed to stand overnight, and then taken
out from water. The weight of the slate plate at this point was
measured and defined as "weight of slate plate after immersion in
water and degassing".
[0142] When the moisture content of the slate plate was calculated
from the following expression based on the measured "weight of
slate plate before immersion in water" and "weight of slate plate
after immersion in water and degassing", the content was 25% (% by
weight).
Moisture content of slate plate (% by weight)=[{(Weight of slate
plate after immersion in water and degassing)-(Weight of slate
plate before immersion in water)}/(Weight of slate plate before
immersion in water))].times.100
[0143] Subsequently, immediately after the prepared adhesive sheet
(test piece) from which the release liner had been peeled off was
crimped and pasted onto the surface (wet surface) of the slate
plate having a moisture content of 25% by reciprocating a 2 kg
roller once, the sheet was immersed in water and allowed to stand
at 23.degree. C. for 24 hours. Thereafter, the slate plate to which
the adhesive sheet (test piece) had been pasted was taken out from
the water, and 90.degree. peel adhesive force (N/25 mm) to the
slate plate was measured at a peeling temperature of 23.degree. C.
and a peeling speed of 100 mm/min using a tensile tester
(Technograph TG-1 kN manufactured by Minebea Inc.). Table 2 shows
results thereof.
[0144] Incidentally, when the measured value of the 90.degree. peel
adhesive force (N/25 mm) is 5N/25 mm or more, the adhesive force to
the wet surface can be evaluated high.
Measurement of Initial Elastic Modulus
[0145] A sample was prepared by rolling the adhesive layer made
from the adhesive composition into a string shape, and for this
sample, using a tensile tester (AG-IS manufactured by Shimadzu
Corporation), the initial elastic modulus of the adhesive layer was
calculated from the stress-strain curve measured when the film was
stretched at a rate of 50 mm/min More specifically, it was
calculated by the same method as in Examples 1 to 6 and Comparative
Examples 1 to 3. Table 2 shows results thereof.
TABLE-US-00002 TABLE 2 Adhesive composition Moisture- Reaction
state Water- 90.degree. peel Initial curable of moisture- absorbing
Tackifier Filler adhesive elastic Base polymer component curable
material (% by (% by force modulus (% by weight) (% by weight)
component (% by weight) weight) weight) (N/25 mm) (kPa) Example 7
Rubber-based Rubber-based Rubber Basonat Unreacted KI gel Escollets
Heavy 20.0 19.7 polymer 1 polymer 2 modifier HA2000 state 1202U
calcium HV300 carbonate 11.6 11.6 23.2 3.7 3.7 23.1 23.1 Example 8
Rubber-based Rubber-based Rubber Basonat Unreacted KI gel Escollets
Heavy 9.4 106.9 polymer 1 polymer 2 modifier HA2000 state 1202U
calcium HV300 carbonate 6.0 6.0 12.0 2.0 2.0 12 60.0 Example 9
Rubber-based polymer 1 Rubber Basonat Unreacted KI gel Escollets
Heavy 5.2 340.2 modifier HA2000 state 1202U calcium HV300 carbonate
12.4 8.7 2.5 2.0 12.4 62.0
[0146] In the adhesive sheets of Example 7 to 9, the 90.degree.
peel adhesive force measured by the above-mentioned measurement
test was all 5 N/25 mm or more, and the sheets had high adhesive
force to the wet surface.
[0147] Although the preferred embodiments of the present invention
have been described above, the present invention is not limited to
the above-described embodiments, and various modifications and
substitutions can be added to the above-described embodiments
without departing from the scope of the present invention.
[0148] Although the preferred embodiments of the present invention
have been described above, the present invention is not limited to
the above-described embodiments, and various modifications and
substitutions can be added to the above-described embodiments
without departing from the scope of the present invention.
[0149] The present application is based on Japanese Patent
Application No. 2016-232749 filed on Nov. 30, 2016 and Japanese
Patent Application No. 2017-229394 filed on Nov. 29, 2017, and the
contents are fully incorporated herein by reference.
* * * * *