Synthetic resins or natural rubbers -- part of the class 520 ser – Synthetic resins – At least one aryl ring which is part of a fused or bridged...
Reexamination Certificate
2002-03-04
2003-11-11
Sanders, Kriellion A. (Department: 1714)
Synthetic resins or natural rubbers -- part of the class 520 ser
Synthetic resins
At least one aryl ring which is part of a fused or bridged...
C524S801000
Reexamination Certificate
active
06646043
ABSTRACT:
The present invention relates to a water dispersion type water and oil repellent composition which is excellent in stability during storage and which can impart excellent water and oil repellency to an object to be treated, and an object treated with it.
It has been conventionally known that an aqueous dispersion having dispersed in an aqueous medium of a polymer containing polymerization units having polymerizable monomers having R
f
groups or a compound containing R
f
groups treats with fibers and imparts water and oil repellency on their surface. (JP-B-47-40467). It has been known that among various water and oil repellent compositions, a copolymer containing as the main components polymerized units of a polymerizable monomer having an R
f
group and a polymerizable monomer having a stearyl group (such as stearyl acrylate) provides more flexible touch and hand than a water and oil repellent composition which employs another polymerizable monomer (such as vinyl chloride).
However, of a conventional water and oil repellent composition, the difference between a specific gravity of stearyl (meth)acrylate (0.86 g/ml) and a specific gravity of a polymerizable monomer having an R
f
group (1.4-1.6 g/ml) is large, and thus it tends to be difficult to uniformly disperse these two polymerizable monomers in a polymerization medium, in a case where a copolymer is obtained by e.g. emulsion polymerization or suspension polymerization, and it may be necessary to employ a specific reactor or agitator or a pre-emulsification apparatus such as a high pressure emulsifier.
Further, when the polymerization is carried out without mixing stearyl acrylate with a polymerizable monomer having an R
f
group uniformly, there will be the fluctuation of the composition of the copolymer, thus decrease the water repellent performance. Further, a difference of specific gravity of dispersed compounds may cause instability of the water and oil repellent composition during storage and decrease chemical or mechanical stability of a processing bath.
Under these circumstances, it is an object of the present invention to improve uniform mixing properties of stearyl (meth)acrylate with a polymerizable monomer having an R
f
group and to achieve uniformalization of a copolymer composition, and to achieve improvement of storage stability of a water dispersion type water and oil repellent composition containing the above copolymer, improvement of initial water and oil repellency of an object treated with it, and improvement of a processing bath stability.
The present invention has been made to solve the above problems. The present inventors have conducted studies on uniform mixing of stearyl (meth)acrylate with a polymerizable monomer containing an R
f
group, and as a result, have found that the concentration of impurities in stearyl (meth)acrylate as a material greatly influences over uniform mixing properties of stearyl (meth)acrylate with a polymerizable monomer having an R group. As a result of further extensive studies, it has been found that the uniform mixing properties will be excellent when the purity of stearyl (meth)acrylate as a material is higher than 91 mass %. Particularly, it has been found that the uniform mixing properties are very excellent when the total amount of stearyl alcohol, a reaction product of stearyl (meth)acrylate and (meth)acrylic acid (impurity X), and a reaction product of stearyl (meth)acrylate and stearyl alcohol (impurity Y) is at most 9 mass % in stearyl (meth)acrylate as a material, and accomplished the present invention.
Namely, the present invention provides a water dispersion type water and oil repellent composition containing a copolymer (A) which has polymerized units based on a polymerizable monomer having an R
f
group and polymerized units based on stearyl (meth)acrylate, and which is produced by using a material having a purity of stearyl (meth)acrylate higher than 91 mass %, wherein the ratio of particles having an average particle diameter of from 30 to 150 nm is at least 80% of the total number of particles of the copolymer (A) in a dispersion medium.
Further, the present invention provides the above water dispersion type water and oil repellent composition, wherein the stearyl (meth)acrylate as the material contains an impurity (B) which is at least one member selected from the group consisting of stearyl alcohol, a reaction product of stearyl (meth)acrylate and (meth)acrylic acid (impurity X), and a reaction product of stearyl (meth)acrylate and stearyl alcohol (impurity Y).
Further, the present invention provides the above water dispersion type water and oil repellent composition, wherein the content of stearyl alcohol in stearyl (meth)acrylate as the material is at most 3 mass %.
Further, the present invention provides the above water dispersion type water and oil repellent composition, wherein the content of the impurity X in stearyl (meth)acrylate as the material is at most 2 mass %.
Further, the present invention provides the above water dispersion type water and oil repellent composition, wherein the content of the impurity Y in stearyl (meth)acrylate as the material is at most 4 mass %.
Further, the present invention provides the above water dispersion type water and oil repellent composition, wherein the polymerizable monomer having a polyfluoroalkyl group is a (meth)acrylate having a perfluoroalkyl group of the carbon number of from 4 to 20.
Further, the present invention provides an object treated with any one of the above water dispersion type water and oil repellent composition.
Now, the present invention will be described in detail with reference to the preferred embodiments.
In this specification, an acrylate and a methacrylate will generally be represented by (meth)acrylate, acrylic acid and methacrylic acid will generally be represented by (meth)acrylic acid, and acrylamide and methacrylamide will generally be represented by (meth)acrylamide.
The R
f
group is a group having at least two hydrogen atoms in an alkyl group substituted by fluorine atoms. The carbon number of the R
f
group is preferably from 2 to 20, particularly preferably from 6 to 16. The R
f
group may be of a linear structure or a branched structure, and a linear structure is particularly preferred. In the case of a branched structure, it is preferred that the branched portion is located at a terminal portion of the R
f
group, and has a short chain of from 1 to 4 carbon atoms.
The R
f
group may contain halogen atoms other than fluorine atoms. As such another halogen atom, a chlorine atom is preferred. Further, an etheric oxygen atom or a thioetheric sulfur atom may be inserted between a carbon—carbon bond in the R
f
group. The structure of the terminal portion of the R
f
group may, for example, be —CF
2
CF
3
, —CF(CF
3
)
2
, —CF
2
H, —CFH
2
or —CF
2
Cl, and —CF
2
CF
3
is preferred.
The number of fluorine atoms in the R
f
group is preferably at least 60%, particularly preferably at least 80%, when represented by [(the number of fluorine atoms in the R
f
group)/(the number of hydrogen atoms contained in an alkyl group corresponding to the same carbon number as the R
f
group)]×100(%).
When the R
f
group is preferably a group having all the hydrogen atoms in an alkyl group substituted by fluorine atoms (i.e. perfluoroalkyl group) or a group having a perfluoroalkyl group at a terminal portion.
The carbon number of the perfluoroalkyl group is preferably from 2 to 20, particularly preferably from 6 to 16. If the carbon number of the perfluoroalkyl group is small, water repellency and oil repellency tend to decrease, and if the carbon number of the perfluoroalkyl group is large, handling of (meth)acrylate having the R
f
group tends to be difficult.
Specific examples of the R
f
group will be given below.
C
4
F
9
— [any one of structurally isomeric groups such as F(CF
2
)
4
—, (CF
3
)
2
CFCF
2
—, (CF
3
)
3
C— and CF
3
CF
2
(CF
3
)CF—], C
5
F
11
— [such as F(CF
2
)
5
—], C
6
F
13
— [such as F(CF
2
)
6
—], C
7
F
15
— [such as F
Funaki Hiroshi
Hirono Takao
Sato Tomoko
Asahi Glass Company Limited
Oblon & Spivak, McClelland, Maier & Neustadt P.C.
Sanders Kriellion A.
LandOfFree
Water dispersion type water and oil repellent composition... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Water dispersion type water and oil repellent composition..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Water dispersion type water and oil repellent composition... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3149136