Cleaning compositions for solid surfaces – auxiliary compositions – Cleaning compositions or processes of preparing – For cleaning a specific substrate or removing a specific...
Reexamination Certificate
2001-05-23
2004-02-10
Boyer, Charles (Department: 1751)
Cleaning compositions for solid surfaces, auxiliary compositions
Cleaning compositions or processes of preparing
For cleaning a specific substrate or removing a specific...
C510S276000, C510S467000, C510S469000, C510S475000, C524S136000, C524S115000, C524S141000
Reexamination Certificate
active
06689731
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to the use of particular phosphoric esters as emulsifiers and dispersants for pigments and fillers, based on polystyrene-block (b)-polyalkylene oxide copolymers.
2. Description of the Related Art
The invention relates to the use of particular phosphoric esters as emulsifiers and dispersants for pigments and fillers, based on polystyrene-block (b)-polyalkylene oxide copolymers.
Phosphoric esters and their use as dispersants are known and can be found in the prior art. For instance, U.S. Pat. No. 4,720,514 describes phosphoric esters of a series of alkylphenol ethoxylates which may be used advantageously to formulate aqueous pigment dispersions. Phosphoric esters for a similar application are described by EP-A-0256427. Furthermore, DE-3542441 discloses bisphosphoric monoesters of block copolymers and salts thereof. It also describes their possible use as dispersants and emulsifiers, in particular for preparing crop protection formulations. U.S. Pat. No. 4,872,916 describes the use of phosphoric esters based on alkylene oxides of straight-chain or branched aliphatics as pigment dispersants. Similarly, U.S. Pat. No. 3,874,891 describes the use of corresponding sulfates. The documents U.S. Pat. Nos. 5,130,463 and 5,151,218 report on phosphoric esters based on hydroxy-terminated polyadducts and polycondensation products, respectively, which are used to produce highly filled polyester molding compounds, in particular for SMC and BMC formulations (SMC=sheet molding compounds; BMC=bulk molding compounds). Bifunctional phosphoric esters, prepared by the Mannich-Moedritzer reaction, and their adsorption characteristics on calcium carbonate are described by J. Appl. Polym. Sci. 65, 2545 (1997). U.S. Pat. No. 4,456,486 describes, inter alia, acidic or neutral phosphoric esters of fatty alcohols and alkoxylated fatty alcohols as treatment compositions for certain blue pigments. Similarly, EP-A-256427 describes the use of phosphoric esters of alkoxylated fatty alcohols to prepare pigment dispersions said to be suitable for aqueous applications. U.S. Pat. No. 4,720,514 describes pigment dispersions prepared using phosphoric esters of alkoxylates of differing structure. U.S. Pat. No. 4,698,099 describes pigment dispersions comprising, as dispersants, phosphoric esters of monohydroxy-terminated polyesters.
DE-A-3930687 describes phosphoric esters (OH)
3−n
PO—(OR)
n
, and their salts wherein R is an aliphatic, cycloaliphatic and/or aromatic radical which contains at least one ether oxygen atom (—O—) and at least one carboxylic acid grouping (—COO—) and/or urethane group (—NHCOO—), is devoid of Zerewitinov hydrogen, and has an average molecular weight of from 200 to 10000, it being possible for some of the hydrogen atoms of the aliphatic groups to have been replaced by halogen atoms, the ratio of the number of carboxylic ester groups and/or urethane groups in the molecule (or in each group R) is in the range from 1:20 to 20:1, and wherein n is 1 or 2. Also mentioned in particular is the use of these phosphoric esters as dispersants. Polyoxyalkylenecarbonyl monoether phosphates and their use as dispersants are also known from GB-A-19980429.
Also known is the use of such phosphoric esters to prepare emulsion polymers, in which context particular attention is drawn to the ready pigmentability of such emulsion polymers, especially those of low coagulum content (DE-A-19810658, JP-A-1 1246799 and WO 99/46337).
DE-A-19806964 describes particular phosphoric esters based on polystyrene-block (b)-polyalkylene oxide copolymers which are prepared from a monofunctional starter alcohol by sequential addition of styrene oxide and an alkylene oxide. Characteristics of these phosphoric esters include the use of at least 2 mol of styrene oxide for their preparation. Likewise described is the use of these phosphoric esters as dispersants for pigments and fillers. DE-A-19940797 describes the use of nonionic, block copolymeric, polyalkylene oxides containing styrene oxide as low-foam pigment wetting agents, the characteristics of the block copolymers including the use of less than 2 mol of styrene oxide for their preparation.
In the production of paints and inks, wetting agents and dispersants facilitate the incorporation of pigments and fillers, which are important formulating constituents that significantly determine the visual appearance and the physicochemical properties of coatings. Optimum use requires firstly that the solids are distributed uniformly in paints and inks and secondly that the state of distribution, once attained, is stabilized. In many cases, the stabilizing action is also undertaken by binder components. This is especially the case with acidic (styrene) acrylates, as used in particular for preparing printing inks. In these cases, pigment wetting agents are used whose action is to wet the pigment surface very rapidly and so to displace the air from the surface of the pigments by the liquid of the millbase. Especially when using solids having a nonpolar surface in aqueous paints, the wetting must be assisted by wetting agents. This permits favorable development of color strength and thus a near-ideal utilization of the input energy.
In the architectural paint industry in particular, moreover, use is made of aqueous pigment pastes, with or without cosolvents, which are used universally in aqueous emulsion paints on an all-acrylic, styrene acrylic or silicate basis and also in nonpolar decorative coatings based on long-oil alkyd, for tinting.
Particularly suitable for this purpose are the phosphoric esters of alkylphenol ethoxylates or fatty alcohol ethoxylates, which additionally contribute to steric and electrostatic stabilization of dispersed pigment states. The high-performance phosphoric esters of alkylphenol ethoxylates have come under criticism on ecotoxicological grounds, and their use is already regulated by legislators in a number of states. In many cases, the phosphoric esters of fatty alcohol ethoxylates fail to match the good properties of the alkylphenol ethoxylate derivatives. Since they lack adsorptive groups, the pigment wetting properties are less pronounced. Furthermore, the unadsorbed portion of this product group, in particular, has the unwanted effect of stabilizing the foam, which can be suppressed only with the aid of substances with a strong defoaming action which, in turn, bring about other adverse phenomena, such as unwanted surface defects. The use of a large number of dispersing additives also impacts negatively on the water resistance or light stability of coatings.
The known phosphoric esters have the disadvantage, moreover, that they are generally not suitable for universal use, since in many cases there is a lack of sufficient compatibility between dispersing additive and binder or dispersing additive and surrounding medium (aqueous or solventborne formulations). Furthermore, the chemical structure of the phosphoric esters has a large part to play: in aqueous formulations it is preferred to use only those phosphoric esters whose molecule does not contain any additional hydrolyzable functional groups, such as ester groups or urethane groups. Frequently, large additions of dispersing additives are necessary in order to suppress the occurrence of agglomerates; the degrees of filling that can be achieved are unsatisfactorily low, the stability of the dispersions and thus the constancy of their viscosity is often inadequate; flocculation and aggregation cannot always be avoided, so that there may be visible separation, leveling defects, and surface defects.
Applications of block copolymers containing styrene oxide in the paints and printing inks industry are still largely unknown. Those which are known include (DE-A-19806964) polystyrene oxide-block (b)-polyalkylene oxide copolymers which, starting from a monofunctional starter alcohol, are reacted to the corresponding phosphoric esters by sequential addition of at least 2 mol of styrene oxide and an alkylene oxide followed b
Esselborn Eberhard
Heilen Wernfried
Lehmann Kathrin
Reuter Ellen
Silber Stefan
Boyer Charles
Frommer & Lawrence & Haug LLP
Goldschmidt AG
LandOfFree
Phosphoric esters as emulsifiers and dispersants does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Phosphoric esters as emulsifiers and dispersants, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Phosphoric esters as emulsifiers and dispersants will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3277144