Synthetic resins or natural rubbers -- part of the class 520 ser – Synthetic resins – Compositions to be polymerized by wave energy wherein said...
Reexamination Certificate
2002-02-12
2004-11-16
Berman, Susan (Department: 1711)
Synthetic resins or natural rubbers -- part of the class 520 ser
Synthetic resins
Compositions to be polymerized by wave energy wherein said...
C522S036000, C522S042000, C522S099000, C522S096000, C522S173000, C522S172000
Reexamination Certificate
active
06818678
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to a resin composition comprising particles and a cured product made from the composition.
PRIOR ART
In recent years, a resin composition exhibiting excellent coatability and capable of forming coatings with high hardness, superior scratch resistance, low curling properties, superb adhesion, and excellent transparency and appearance is desired as a protective coating material to prevent stains or scratches on the surface of various substrates, an adhesive for various substrates, a sealing material, or a vehicle for printing ink. Various materials comprising colloidal silica have been proposed with an objective to improve scratch resistance among these required characteristics. For example, U.S. Pat. No. 3,451,838 and U.S. Pat. No. 2,404,357 disclose compositions comprising a hydrolyzate of alkoxysilane and colloidal silica as major components to be used as a heat-curable coating material. Japanese Patent Publication No. 21815/1987 discloses a composition for a photocurable coating material comprising an acrylate and particles of colloidal silica of which the surface is modified by methacryloxy silane. A feature of these coating materials is to improve performance of the coating materials by treating the surface of silica particles with a specific organic silane or under specific conditions. However, these coating materials do not necessarily satisfy satisfactorily all of the requirements such as coatability, high hardness, superior scratch resistance, low curling properties, and superb adhesion, when made into coatings. Specifically, to increase hardness of the coatings, a crosslinking density of the coatings must be increased after cure. However, an increase in the hardness accompanies cure shrinkage of the coatings, which produced a large curl. To have well balanced hardness and low curl properties is thus difficult.
PROBLEMS TO BE SOLVED BY THE INVENTION
The present invention has been completed in view of the above-described problems and has an object of providing a resin composition exhibiting excellent coatability and capable of forming coatings with high hardness, superior scratch resistance, low curling properties, and superb adhesion, particularly well balanced high hardness and low curling properties, on the surface of various substrates, such as, for example, plastics (polycarbonate, polymethylmethacrylate, polystyrene, polyester, polyolefin, epoxy resins, melamine resins, triacetyl cellulose resins, ABS resins, AS resins, norbornene resins, etc.), metals, woods, papers, glasses, and slates, as well as the cured products made from the resin composition. The resin composition and the cured product are suitable for use, for example, as a protective coating material to prevent stains or scratches on plastic optical parts, touch panels, film-type liquid crystal elements, plastic containers, or flooring materials, wall materials, and artificial marbles which are used for architectural interior finish; as an adhesive for various substrates, a sealing material, and a vehicle for printing ink; and the like.
MEANS FOR SOLVING THE PROBLEMS
As a result of extensive studies, the present inventors have found that the products with well balanced high hardness and low curling properties can be achieved by a resin composition comprising: (A) particles produced by bonding oxide particles of specific element and an organic compound containing a polymerizable unsaturated group (preferably the specific organic compound of formula (1)
wherein X represents NH, O (oxygen atom), or S (sulfur atom), and Y represents O or S), (B) a specific oligomer-type radiation polymerization initiator, and (C) a compound having at least two polymerizable unsaturated groups in the molecule; and cured products of the resin composition.
PREFERRED EMBODIMENT OF THE INVENTION
The resin composition and the cured products thereof of the present invention will now be described in more detail.
I. Resin Composition
The resin composition of the present invention comprises (A) particles produced by bonding oxide particles of specific element and an organic compound containing a polymerizable unsaturated group (preferably the specific organic compound of the above formula (1)) (such particles may be called “crosslinkable particles (A)”), (B) an oligomer-type radiation polymerization initiator having a site which produces photo-radicals by radiation (hereinafter may be called “oligomer-type radiation polymerization initiator”), and (C) a compound having at least two polymerizable unsaturated groups in the molecule (hereinafter may be called “compound (C)”).
Each component for the resin composition of the present invention will be described in more detail.
1. Crosslinkable Particles (A)
The crosslinkable particles (A) used in the present invention are the particles produced by bonding particles of at least one oxide of an element selected from the group consisting of silicon, aluminum, zirconium, titanium, zinc, germanium, indium, tin, antimony, and cerium, and an organic compound containing a polymerizable unsaturated group (preferably an organic compound containing the group shown by the above formula (1)).
(1) Oxide Particles
For obtaining uncolored cured coatings from the resin composition, the oxide particles used in the present invention should be particles of at least one oxide of an element selected from the group consisting of silicon, aluminum, zirconium, titanium, zinc, germanium, indium, tin, antimony, and cerium.
As these oxides, for example, silica, alumina, zirconia, titania, zinc oxide, germanium oxide, indium oxide, tin oxide, indium-tin oxide (ITO), antimony oxide, and cerium oxide can be given. Of these, silica, alumina, zirconia, and antimony oxide are preferable from the viewpoint of high hardness. These compounds may be used either individually or in combination of two or more. In addition, oxide particles of these elements are preferably in the form of a powder or a solvent dispersion sol. When the oxide particles are in the form of dispersion, an organic solvent is preferable as a dispersion medium from the viewpoint of mutual solubility with other components and dispersibility. As examples of such organic solvents, alcohols such as methanol, ethanol, isopropanol, butanol, and octanol; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; esters such as ethyl acetate, butyl acetate, ethyl lactate, and &ggr;-butyrolactone; ethers such as ethylene glycol monomethyl ether and diethylene glycol monobutyl ether; aromatic hydrocarbons such as benzene, toluene, and xylene; and amides such as dimethylformamide, dimethylacetamide, and N-methylpyrrolidone can be given. Of these, methanol, isopropanol, butanol, methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, butyl acetate, toluene, and xylene are preferable.
The number average particle diameter of the oxide particles is from 0.001 &mgr;m to 2 &mgr;m, preferably from 0.001 &mgr;m to 0.2 &mgr;m, and more preferably from 0.001 &mgr;m to 0.1 &mgr;m. If the number average particle diameter is more than 2 &mgr;m, transparency of the cured product and surface conditions of the coating tend to be impaired. Moreover, various surfactants and amines may be added to improve dispersibility of particles.
Among silicon oxide particles, given as examples of commercially available products of silica particles are colloidal silica available under the trade names Methanol Silica Sol, IPA-ST, MEK-ST, NBA-ST, XBA-ST, DMAC-ST, ST-UP, ST-OUP, ST-20, ST-40, ST-C, ST-N, ST-O, ST-50, ST-OL, etc., manufactured by Nissan Chemical Industries, Ltd. As powdery silica, products available under the trade names AEROSIL 130, AEROSIL 300, AEROSIL 380, AEROSIL TT600, and AEROSIL OX50 (manufactured by Japan Aerosil Co., Ltd.), Sildex H31, H32, H51, H52, H121, H122 (manufactured by Asahi Glass Co., Ltd.), E220A, E220 (manufactured by Nippon Silica Industrial Co., Ltd.), SYLYSIA470 (manufactured by Fuji Silycia Chemical Co., Ltd.) and SG Flake (manufactured by Nippon Sheet Glass Co., Ltd.), and t
Nishiwaki Isao
Ukachi Takashi
Yamaguchi Yoshikazu
Yashiro Takao
Berman Susan
DSM IP Assets B.V.
Mayer Brown Rowe & Maw LLP
LandOfFree
Resin composition comprising particles does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Resin composition comprising particles, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Resin composition comprising particles will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3330805