Stock material or miscellaneous articles – Coated or structually defined flake – particle – cell – strand,...
Reexamination Certificate
2000-07-07
2001-11-06
Hampton-Hightower, P. (Department: 1711)
Stock material or miscellaneous articles
Coated or structually defined flake, particle, cell, strand,...
C428S364000, C428S394000
Reexamination Certificate
active
06312802
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a polymer for imparting high light resistance and weather resistance (hereinafter simply referred to as “light resistance”) to fibers. The invention further relates to a highly light resistant fiber containing the polymer, to a highly light resistant fiber having a layer containing the polymer on its surface, and to a process for the production of the fibers.
2. Description of the Related Art
Polyurethane fibers are characterized by high elasticity and are widely used in numerous applications such as stockings, undergarments, as well as swimsuits, ski suits, and other sportswear, and elastic bandages, artificial vessels, and other medical articles. However, such polyurethane fibers are poor in light resistance. Specifically, by action of ultraviolet rays in sunlight or light from fluorescent lamps, the molecules of polyurethane fibers are photolyzed, and the strength and other properties of the fibers are deteriorated or dyed fibers are discolored.
Separately, polyester fibers are highly strong and highly elastic, are satisfactorily resistant to heat and chemicals, and are in wide use for clothing materials and industrial materials. The polyester fibers are more resistant to light and are therefore more resistant to light-induced deterioration and discoloring than polyurethane fibers and polyamide fibers. Demands on the use of such polyester fibers for interior members of cars and other materials have been increased, as such materials are often exposed to sunlight. However, higher light resistance is required as high grade cars are demanded. Improvements in light resistance of other fibers have been also demanded.
To improve light resistance, light resistance improving agents such as ultraviolet absorbents and antioxidants which are low molecular weight compounds are conventionally added to fibers (e.g., Japanese Unexamined Patent Application Publication No. 4-153316). Such light resistance improving agents are added to fibers by a process which comprises the step of coating surfaces of fibers with the light resistance improving agents after the formation of fibers (surface treatment process), or by a process which comprises the steps of adding the light resistance improving agents to a spinning material prior to a spinning process, and forming fibers from the resulting mixture (material adding process). However, according to the surface treatment process, the light resistance improving agents is readily peeled off from the fiber and a long-term improvement effect on light resistance cannot be significantly expected. In addition, the feeling of the resulting fibers is changed and high quality products cannot be obtained. In contrast, the material adding process is disadvantageous in that in wet spinning, for example, the light resistance improving agents is dissolved out into a coagulation bath, and only a portion of the added light resistance improving agents remains in the fiber. In addition, such a low molecular weight light resistance improving agents bleeds out on the surface of the fiber and, ultimately, is peeled out from the fiber, and the appearance of the fiber is deteriorated with time.
SUMMARY OF THE INVENTION
Accordingly, an object of the invention is to provide a polymer which is capable of imparting a high light resistance to fibers over a long time, and to provide a highly light resistant fiber.
Specifically, the invention provides, in an aspect, a polymer for imparting light resistance to fibers (hereinafter referred to as “light resistance imparting polymer”). The polymer is obtained by radical polymerizing a monomer composition including an ultraviolet stabilizable monomer of the following formula (1) or (2):
wherin R
1
is a hydrogen atom or a cyano group, each of R
2
and R
3
is independtly a hydrogen atom or a methyl group, R
4
is a hydrogen atom or a hydrocarbon group, and X is an oxygen atom or an imino goup.
wherin R
1
is a hydrogen atom or a cyano group, each of R
2
, R
3
, R
2
′, and R
3
′ is independently a hydrogen atom or a methyl group, and X is an oxeygen atom or an imino group.
In another aspect, invention provides a polymer for imparting light resistance to fibers. This polymer is obtained by radical polymerizing a monomer composition comprising an ultraviolet absorptive monomer of the following formula (3) or (4):
wherein R
5
is a hydrogen atom or a hydrocarbon group, R
6
is an alkylene group, R
7
is a hydrogen atom or a methyl group, and Y is a hydrogen atom, a halogen atom, a hydrocarbon group, an alkoxy group, a cyano group, or a nitro group;
wherein R
8
is an alkylene group, and R
9
is a hydrogen atom or a methyl group.
The invented light resistance imparting polymer may also be a mixture of a polymer obtained by polymerizing a monomer composition including the ultraviolet stabilizable monomer and a polymer obtained by polymerizing a monomer composition including the ultraviolet absorptive monomer.
The invention is also related to a highly light resistant fiber containing the light resistance imparting polymer inside the fiber, and a highly light resistant fiber having a layer including the light resistance imparting polymer formed on its surface. In addition and advantageously, the invention is directed to a process for producing a highly light resistant fiber. This process includes the steps of blending the light resistance imparting polymer with a material for the production of a fiber, and spinning the resulting mixture.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The invented light resistance imparting polymer for fibers is a polymer obtained by radical polymerizing a monomer composition comprising the ultraviolet stabilizable monomer of the formula (1) or (2) and/or the ultraviolet absorptive monomer of the formula (3) or (4), or is a mixture of a polymer obtained by radical polymerizing a monomer composition containing the ultraviolet stabilizable monomer, and a polymer obtained by radical polymerizing a monomer composition containing the ultraviolet absorptive monomer. The invented light resistance imparting polymer can therefore impart high light resistance to fibers. By blending the polymer with a material for the production of fibers prior to spinning and other fiber formation processes, the resulting formed fiber comprises a polymer chain having fiber-forming property (a polymer chain predominantly constitutes the fiber) entangled with a molecular chain of the light resistance imparting polymer on the molecular level. By this configuration, the bleedout and peeling off of the light resistance imparting polymer from the fiber surface and deterioration of appearance of the fiber can be significantly inhibited.
Particularly, the conventional low molecular weight light resistance improving agents are readily dropped out from fibers in humid surroundings, but the invented light resistance imparting polymer can impart light resistance to fibers over a long time even in humid surroundings. In addition, even when fibers are produced by wet spinning, the light resistance imparting polymer does not dissolve into a coagulation bath during spinning procedure. The invention will now be described in further detail below.
The invented light resistance imparting polymer is obtained by using a monomer composition essentially comprising a specific ultraviolet stabilizable monomer and/or ultraviolet absorptive monomer. The term “ultraviolet stabilizable monomer” means and includes monomers which do not belong to ultraviolet absorbents (UVAs) and do not have an ultraviolet absorbing property but stabilize a polymer satisfactorily against ultraviolet rays by a different activity or mechanism from UVAs and are radical polymerizable. The stabilizing activity against ultraviolet rays has not yet been sufficiently clarified, but this is probably because N-oxy radicals, which are formed by the oxidation of an N-substituent on a piperidine skeleton, trap alkyl radicals induced by ultraviolet rays.
The specific ultraviolet stabilizable monomers f
Aoyama Takahiro
Nishida Toshifumi
Noda Nobuhisa
Hampton-Hightower P.
Nippon Shokubai Co. , Ltd.
Wenderoth , Lind & Ponack, L.L.P.
LandOfFree
Polymers for imparting light resistance to fibers, highly... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Polymers for imparting light resistance to fibers, highly..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Polymers for imparting light resistance to fibers, highly... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2597829