KR20190021186A - On-site formation of stable suspension of gelatinous particles for separation and suspension of inert abrasive particles - Google Patents

Abstract

A stable aqueous, semi-aqueous or non-aqueous suspension medium for suspending inert organic or inorganic particles in a suspension medium containing gel particles as a separating agent for inert organic or inorganic particles, said gel particles being inert Thereby preventing hard aggregation of the particles.

Description

On-site formation of stable suspension of gelatinous particles for separation and suspension of inert abrasive particles

The present invention relates to sol or gel particles in a liquid medium or solely as a suspension medium. More specifically, the present invention relates to a lapping application, a wire saw cutting, a chemical mechanical polishing and / or a metal forming and finishing planarization, a free polishing There is provided a carrier system having long term dispersion stability for a particle suspension, which is used with a wide range of inert particles that can be suspended, including abrasive, non-abrasive, inert solid organic particles, ceramic particles, and the like.

Although non-aqueous, semi-aqueous and aqueous suspensions of non-colloidal dense abrasive grains have been used for wire-saw cutting and lapping of wafers from the past, stable slurries of particles capable of maintaining the separation of inert particles in suspension over time The suspension could not be obtained. U.S. Patent No. 5,099,820 to Stricot discloses abrasives in which silicon carbide particles are suspended in water or oil. However, the suspension is not stable and does not provide uniform lubrication and wire cutting. These compositions require vigorous stirring to maintain a uniform suspension of the particles and even rapidly settle under stagnation conditions even while the work pieces are being cut under agitation.

U.S. Patent No. 6,602,834 to Ward et al., Which is incorporated herein by reference, discloses a non-aqueous or semi-aqueous cutting and lubricating composition for use with a wire saw, For providing magic repulsion and particle-to-particle interference, it depends on the surfactant or organic polymer electrolyte and pH. U.S. Patent No. 6,054,422 to Ward et al., Also incorporated herein by reference, discloses a lubricating composition containing up to 70% by weight of abrasive grit material in suspension using a mixture of high molecular weight and low molecular weight polyalkylene glycols as the suspending agent .

In the production of silicon, SiC, sapphire, GaAs, optical glass and other wafers used in microelectronics, solar cells, LEDs, broadband devices, optics / lasers, wafer polishing, CMP applications and various other industries, ingots, bricks, boules, and the like. The next step following the initial cutting of wafers, disks, sculptures, etc., is to lap the cut wafer to soften the surface, reduce the total thickness variation (TTV) that is not applicable to the solar wafer, And to produce wafers for final polishing, which are mainly applicable to semiconductor and optical wafer production. Generally, an aqueous carrier is used as the suspending medium for the lapping abrasive used in this step. Wrapping abrasives can include, but are not limited to: SiC, aluminum oxide, ZrO ₂ , silica, CeO ₂ , diamond, and the like. The lapping slurry uses abrasive particles having a size in the range of about 0.1-10 mu m. This means that the suspended abrasive particles are typically non-colloidal in size or quality. This does not exclude the use of colloidal lapping abrasives, i.e. abrasive particles ranging in size from about 0.001 to 0.5 [mu] m in size, but such particles are generally not used in lapping slurries.

Lapping slurries for wafers, mechanical gears for the automotive industry, ceramics, etc., receive a lot of shearing, grinding and polishing forces during the wafer lapping process. During the " planetary lapping " process, the slurry is injected into the surface of the wafer placed between two large metals, such as steel plates and / or steel plates. Counter rotation of the top and bottom plates supporting the wafer compresses the slurry between the top plate and the wafer surface. The solids in the compressed slurry contact the wafer and angular momentum causes a polishing action to remove surface wafer defects and " etch " the desired amount of wafer surface material. For all currently used aqueous slurries in lapping, this effect on slurry and the design of the lapping equipment propagate particle aggregation in the reservoir, in the feed line, in the wrapper, on the metal plate, and the like. Such particle agglomeration has the additional deleterious effect of creating a " dark-scratch " that is damaged on the wrapped wafer. Such wafers must be discarded at high cost.

The aqueous suspension of non-colloidal, NCOL, dense abrasive grains has been a serious problem for "wafer" manufacturers for decades. To date, there are no low viscosity waterborne carriers that hold the NCOL abrasive suspension for very short periods of a few minutes. The abrasive particles then begin to agglomerate and settle out from the suspension, such as a very hard " concrete-like " cake from the bottom of the vessel. In currently used " aqueous " slurries, the settling of these abrasive particles occurs rapidly even during continuous mixing or recirculation.

These particles, which settle at the bottom of the vessel as a " hard settled cake ", are extremely difficult to suspend in any attempt for resuspension. Any attempt to reproduce the slurry to maintain the original particle size distribution of the initial abrasive prior to use can never be achieved by simple mixing, stirring, shaking, and the like. As a result, these slurries become unstable and are quickly discarded, rendering expensive abrasives, time, manpower and effort obsolete.

In prior art suspensions, temperature and pH serve as factors that determine the period during which the suspension remains homogeneous and uniform during long-term stationary storage. The inorganic particles may be maintained as a suspension in aqueous and non-aqueous solvents depending on the particle size, lattice structure and density, but tend to aggregate and settle out of the suspension during storage in the settled state. In addition, there is no customized suspending medium. The suspensions remain in the same medium as they are formed.

A general objective of the present invention is to provide a wide variety of gel particles formed or derived from a wide variety of different compounds, polymers and materials under a wide variety of conditions, wherein the " in situ " Occurs under multiple sets of conditions, component material compositions, and variable field-forming media across organic, inorganic and semi-organic materials; All of these particles are those that provide long-term inert particle separation and suspension in a stable slurry suspension. These stable slurry suspensions include wire saw applications in which ingots or other large materials are cut into wafers, discs or other machined, sliced, crushed or molded pieces; Lapping applications, CMP applications, processing, grinding and grinding applications; Can be used for automatic metal gear forming applications, optical and optoelectronic cutting, grinding and lapping applications, and particle separation.

It is also an object of the present invention to provide in situ formed gel particles in a non-aqueous medium, and examples which exhibit the same performance and suspension properties and gel particle properties as the in situ generated gel particles in an aqueous medium are also provided. These "non-aqueous" gel particles are preferably neutralized in situ or partially neutralized in an organic medium, preferably polyethylene glycol, polypropylene glycol, diethylene glycol, or other suitable glycols to provide other gel- It is preferable to be composed of polyacrylic acid, polymaleic acid, polyalkyl acrylic acid or copolymers thereof, which produces typical gel-particle species in a forming medium satisfying the same performance. The gel particles formed in the non-aqueous medium also contain the typical characteristics of the gel-particles which are formed in situ in the suspension medium or " gel-particle " forming medium used, The formed gel-particles are transferred to a second medium suitable for inert or abrasive particle suspensions; Provided that the second medium does not adversely affect or degrade the suspension performance of the " gel-particles " in the final selection medium.

It is a further object of the present invention to provide a process for the preparation of a suspension which is inert in a low-toxic and / or low-viscosity to medium-viscosity carrier and which is free of particle agglomeration or agglomeration in the suspension or absent as a solid agglomerated on the bottom of the suspension slurry container Wherein the density of the suspension carrier is somewhat lower than that of the suspended " gel-particles ", wherein the density of the suspension carrier is characterized by the ability to permit continuous separation of abrasive particles or non-abrasive particles. It is a further object of the present invention to provide non-reactive gel particles for stable suspensions of colloidal or NCO, abrasive or non-abrasive particles in a medium medium or near-mid pH medium.

It is a further object of the present invention to provide a means for suspending colloidal or NCOL abrasives or other particles in a liquid without depending on the final slurry viscosity. It is another object of the present invention to provide gel particles which can be added to various basic carriers for separating and suspending inert particles and which can also act as a lubricant. It is another object of the present invention to provide an aqueous or semi-aqueous carrier / slurry system that does not cause corrosion of metals such as iron, carbon steel, and the like.

Other objects will become apparent from the following description.

Summary of the Invention

The present invention relates to sol-gel or gel particles which can be used alone or in an organic or aqueous medium to suspend solid inert particles and to particle suspensions in a carrier. Gel particles (hereinafter referred to as " gel particles ") including sol-gels, gel particles, gelatinous precipitates and the like are used to suspend inert particles and serve as lubricants in various applications as particles alone or as a liquid medium. The formed suspension slurry composition may contain the gel particles in an amount ranging from about 0.1% to about 60% by weight of the carrier. The gel particles and the base carrier can be used without adding other suspended particles as a lubricant. The aqueous content of the carrier may contain from about 1 to 100% by weight of water and the organic solvent added to any carrier is less than 100% water. The organic medium may comprise alkylene and polyalkylene glycols, depending on the variety of solvents used, depending on the intended use, including suspensions " gel-particles " comprising abrasive particles suspended in an aqueous medium and gel- Reactive or inert. The suspended gel particles have a density somewhat similar to or slightly higher than the carrier-solvent composition.

Gel particles, preferably aluminum hydroxide for on-site aqueous formation and suspension use; (Al (OH) ₃ ), magnesium hydroxide; Mg (OH) ₂ , zinc hydroxide; Zn (OH) ₂ , copper hydroxide; Cu (OH) ₂ , and the like can be produced in an aqueous medium or an aqueous-based medium and then separated and then transferred to a second aqueous or nonaqueous medium or used alone or in various cases. The gel particles may be required to customarily formulate a suspension or slurry of a stable suspended abrasive or non-abrasive particles referred to as a lubricant or collectively as a slurry. However, the gel particles can be formed of other metal sulfides, hydroxides, and oxide hydrates that can form precipitates suspended in water within a pH range of 3-12.

The present invention includes methods of suspending inert colloidal or non-colloidal abrasives or non-abrasive inert particles in a stable aqueous, semi-aqueous or organic carrier medium. The carrier medium forms a liquid that forms suspended particles in situ to form an appropriate concentration of suspended particles relative to inert particles so as to produce sufficient interference with the settling of the inert particles in the carrier medium. The carrier medium comprises from 0.1 to 60% by weight of suspending particles different from the inert particles, selected from the group consisting of alkaline earth metals and transition metal hydroxides, oxyhydroxides and oxide hydrates, the suspended particles having a pH of from 4 to 12 In the carrier medium and including the carrier medium, to suspend the suspended particles in situ. The on-site molding of suspended particles in the carrier medium has a distinct molecular structure, stereoregularity, rheological properties and physical structure distinct from the carrier medium and has a density greater than that of the carrier medium, visually identifiable and distinct from the carrier medium And a measurable size difference in the range of about 2-3 [mu] m to 500 [mu] m, and that the interaction between the gel-particle structure and the internally contained carrier molecules is possible and likely to occur Results in suspended particles containing molecules of the carrier medium in which suspended particles are formed, without the need for further chemical reaction with the carrier medium. Finally, suspended particles exhibit this property irrespective of their formation mechanism or origin of components.

As a direct consequence of the on-site formation of suspended particles, the inert particles have an attractive force between the suspended particles and the inert particles, which provides physical interference between the suspended particles and the inert particles, proximity for chemical, physical or physicochemical interference, And electrostatic repulsive repulsion of suspended particles from themselves (both of which prevent agglomeration and aggregation of the inert particles in the carrier medium over time).

The components in which the in-situ formed suspension particles are formed therefrom, which may be gel particles, sol-gel particles or gelatinous precipitates of a plurality of chemical compounds, are described in more detail below. In addition, depending on the composition of the suspended particles, the suspended particles may be formed in a medium separate from the final carrier medium.

Description of preferred embodiments

The present invention provides means for providing a variety of gel particles formed or derived from a wide variety of different compounds, polymers and materials under a wide variety of conditions, wherein the " in situ " Semi-aqueous or semi-organic material, without any agglomeration or particle-hardening precipitation using sol-gel or gel particles, under conditions, compositional material composition and various sets of variable field-forming media across organic, It is also possible to provide a stable suspension of inert or abrasive particles in the medium by means of means of stable cutting, slicing, polishing or the like, for the finishing of the hard material, as a non-limiting example of a wafer, disk, special hard metal, semi- Slicing, cutting, grinding, milling, lapping, polishing, polishing, etc. by the unique "stability characteristics" - forming, is prepared.

According to one aspect of the present invention there is provided a suspension and / or lubricant carrier and slurry composition for wire saw application such as cutting or slicing slurry, lubricant, lapping or abrasive slurry, non-abrasive slurry, etc., Not only at the temperature but also at the high temperature. The gel particles are maintained as an aqueous, semi-aqueous or non-aqueous suspension at about 0.1 to 80 weight percent of the carrier thereby providing sufficient particle-to-particle interference for agglomeration or hard sedimentation of abrasive particles or inert particles, The " gel particle " density is somewhat larger than the density of the " gel particle " The gel particles may be prepared separately and then used alone or as a lubricant and / or suspension in a carrier or combined with a suitable polar or non-polar solvent depending on the suspension compatibility of the carrier medium and the gel-particles. As an example, it is advantageous for the gel particles to be used in various types of glycols such that the lubricating composition can be used customarily for a particular application.

In many cases, it is desirable to use two or more suspending agents to obtain a homogeneous dispersion as much as possible. This is because the density of the particles to be suspended and / or the static charge from the suspended particles may be different. For example, in the wire saw cutting process, cut and cut particles are present from the ingot to be cut. Other processes may have denser or similar contaminants than suspended media.

These suspended particles can be used to form suspended particulate precipitates in an aqueous or semi-aqueous medium at a pH in the range of about 3 to 12, in the case of aqueous systems, in situ formed alkaline earth metal Or transition metal hydroxides, oxy-hydroxides, and oxide hydrates (also referred to as hydrous oxides). Particles to be suspended include inert particles having a particle size of about 1 to 100 占 퐉 for conventional abrasive or non-abrasive particles, pigment making, wire saw cutting, metal finishing applications, and smaller sizes, Inert particles, generally in the range of about 0.1 to 10 mu m, and smaller sizes for CMP applications, i.e., particles in the range of about 10 to 500 nm. Preferred suspended particles are those formed on site or separately, such as when the metal salt is formed of a metal hydroxide. In this case, the density of the precipitated gelatinous " gel particles " produced on-site is larger and the surface area of the gel particles formed on-site is generally less than that of the " dried " The in situ formed gel particles will generally maintain a higher density than any of the second medium in which the on-site carrier medium, or formed " gel particles, " are placed. In addition, there is generally a broader particle size distribution of the in situ formed gel particles of the present invention. Due to the advantages of having gel particles separately from the carrier medium, it is possible to mix different particle sizes for some applications, especially in coating applications.

The abrasive material used in the above compositions includes powders of diamond, silica, tungsten carbide, silicon carbide, boron carbide, silicon nitride, silicon dioxide, cerium oxide, zirconium oxide, aluminum oxide, or other hard grit " . Generally, the average particle size range is in the range of about 0.5-100 microns, preferably about 2-50 microns, or a mixture thereof. The concentration of inert particles to be suspended in the carrier in the suspension medium or in most applications will be from about 0.1 to 60 weight percent based on the total suspension.

Solvents that can be used with the aqueous medium are polar solvents including alcohols, amides, esters, ethers, ketones, glycols, glycol ethers, alkyllactones or sulfoxides. Specifically, examples of the polar solvent include dimethyl dimethyl sulfoxide (DMSO), dimethylacetamide (DMAC), N-methylpyrrolidone (NMP), (gamma) -butyrolactone, diethylene glycol ethylether, Glycol methyl ether, tripropylene glycol monomethyl ether, various glycols, polyethylene glycol and polypropylene glycol, and the like.

The organic solvent is used in some cases to provide the required viscosity level for the resulting slurry to be produced. Other uses of the organic solvent include lowering the freezing point of the slurry carrier. In the case of aqueous formed gel-particles, they are non-reactive with water or with suspended particles or suspended gel particles, solvents are inert, completely soluble in water or miscible with water, low in toxicity and weak in odor , The choice of solvent is not so important.

Non-limiting examples of suspension particles that can be used in the case of aqueous formed gel-particles include oxides other than metal hydroxides, oxide hydrates (or hydrous oxides) and abrasive particles forming aqueous or semi-aqueous suspensions; gel particles, gelatinous Precipitates, sol-gels, colloidal or non-colloidal suspensions, and the like. These suspended particles are an important component of the present invention and can be settled on the bottom of the vessel over time, but do not settle to such a degree that they form a hard agglomerate or particle " cake " This includes, but is not limited to, in situ, in the presence or absence of a medium, a hydroxide form such as a metal or nonmetal Bronsted base such as potassium hydroxide, tetramethylammonium hydroxide, sodium hydroxide, sodium carbonate, hydroxide / tetraethylammonium carbonate, Such as metal sulfates, which are converted to hydroxides by hydrolysis and hydrolysis, which can be represented by the following chemical reaction formula: < RTI ID = 0.0 >

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An insoluble fully suspended gelatinous precipitate or a precipitate of aluminum is formed in a pH range of about 4 to 12. [

Non-limiting examples of suitable metal hydroxides for use in the aqueous formed crab-particle examples of the present invention include copper hydroxide, aluminum hydroxide, barium hydroxide, ferrous hydroxide or ferric and Zn (OH) 2, It does not. Examples of metal sulfides, salts or oxide hydrates that can be used to form or formulate suspended particles in aqueous systems of the present invention include transition metal oxides such as Zn-salt, ZnS, SnO2xH2O, tin-salt, SnS, AI203xH20, And the like. These salts, sulfides, oxy-hydroxides, oxide hydrates (or hydrated oxides), etc., can also be used to form the corresponding hydroxides, which in the case of the exemplary aqueous carrier systems of the present invention, Lt; RTI ID = 0.0 > a < / RTI > solid particle suspension. For Al (OH) ₃ or other aluminum oxide or hydroxide species, the pH range used for the carrier is about 3-12. The preferred pH range is 5-10 and the most preferred pH range is 6-9. Suspended precipitates or gel-particles include particles that are denser than the carrier solvent, and those that are naturally precipitated or suspended. It is understood that metal oxy-hydroxides, hydroxides or hydroxides with high densities are present in the aqueous system of the present invention except in situ or precipitated in aqueous or semi-aqueous media, which are added into the carrier system of the present invention.

Precise measurement tools were used to quantitatively determine the "soft-settle" feature level of polishing slurries, such as SiC slurries. The slurry stability of a particular suspending carrier is determined by its soft-settle retention (SSR) or otherwise described by measuring the resistance of a solid suspension to forming a hard cake at the bottom of the container. This is also obtained by suspension volume retention (SVR), which measures how effectively the solid particles are kept apart from each other in the suspension. To see if the carrier is capable of producing a stable slurry, a 15-25% SiC JIS 1000 grade, i.e. a slurry having an average particle size of about 13-16 [mu] m, was prepared, Both SSR and SVR were measured over a long period while stored in a 50 ml gradient tube with bottom.

The soft-sedimentation characteristics were evaluated using the IMADA Vertical Manual Lever Force Test Stand, Model LV-100. IMADA measures the force that a probe having a standard diameter circular pad at the shaft bottom passes through the slurry and reaches the bottom of the vessel. To measure the force required, the IMDA set point was modified by extending the probe shaft so that the probe could extend to and reach a point within 1 mm of the conical bottom of the gradient test tube: the bottom had a circular It is not more than 1 mm larger than the diameter of the probe bottom. The probes were extended by attaching extended elongated bars to the probe. The force measured by IMADA is reported in hundredths of a pound. A low SSR means that the abrasive is easily resubmitted, for example if the value is higher than 1.0, it means that the abrasive is hardly settled and is not easily resuspended.

Suspension volume retention (SVR) is determined by measuring the volume of the solid in the test tube taken in mL, dividing this volume by the total volume (mL) of the slurry in the test tube, and multiplying the result by 100 It is obtained as a percentage. In general, though not always, the higher the SVR value, or closer to 100%, the better the ability of the carrier to maintain the abrasive in the suspension. The SVR of the slurry generally decreases over time, but does not necessarily indicate the soft-settling properties of the slurry. On an irregular basis, the SVR readout will not match the expected value under the " soft-settling test conditions for the slurry under study. &Quot; This indicates that even though SVR may be a qualitative indicator, Means that the SVR does not provide a consistent value for the " soft-precipitated " slurry as opposed to the sedimentation [SSR] value. Thus, while the SVR often indicates the overall stability of the slurry, It is not a standard.

The degree of stabilization of the abrasive slurry suspended by the generally formed gel particles described as part of the present invention, and the SSR value vs. the long term stored slurry. An example of an irregular, semi-intuitive relationship between SVRs for the same slurry is as follows.

A superficially non-aqueous " gel-particle " suspended carrier was spotted in PEG-200 in the following manner. Suspension gel-particles were formed by partial neutralization of a copolymer of acrylic acid and maleic acid with a final molecular weight > The polymer was purchased as an initial 50/50 (wt / wt) aqueous solution, and the suspension carrier PEG-200 was added thereto to form a " solution " of a transparent to slightly turbid copolymeric acid. The polymeric acid was partially neutralized with an amino-hydroxide base until adequate " gel-particles " were formed in the PEG suspension medium at a concentration sufficient to suspend ~ 48% SiC abrasive on a wt / wt basis.

This slurry is used to cut a large number of Si ingots into wafers and then the slurry is " depleted " when the total weight exceeds 300 lbs per 300 gal. 4 'x 4' x 4 'containers. The spent slurries were " cold stored " in ambient conditions without temperature and / or humidity regulation in a stagnant mode for four years. Using a 5 "long steel shaft (large-sized IMADA rod) with a round circular disc diameter of ~ 8", the "IMADA rod" was slowly dropped downward into the slurry inside each vessel without external force to qualitatively determine the hardness of the precipitated solid. The SVR of these solids was measured as < 30%. ≪ / RTI > The IMADA rod was used to measure the " soft-settling " Successfully dropped to the bottom, which proves that the SSR is even ~ even after four years of stash.

Similar results were obtained in all cases when this experiment was repeated at least 12 times for other glycol-based, non-aqueous spent slurry containers. This " soft-sedimentation " for a high solids loading slurry after a period of four years clearly demonstrates the efficiency and persistence of the " gel particle "

Both the standard bar penetration depth and the calibration of the tool were checked daily to ensure that the measuring tool used to obtain the soft-settle resistance (SSR) repeatedly measures the "cake-penetration resistance" . For slurries formed in a good suspension carrier, the penetration SSR is < 0.1 lbs. &Lt; RTI ID = 0.0 &gt; lbs. &Lt; / RTI &gt; for long term shelf life under controlled test conditions over a period of about 4 weeks to 6 weeks. Respectively. In the case of a slurry formed in the presence of &quot; gel-particles &quot;, for example in a standard PEG-200, -300, or -400, or an unsatisfactory suspension carrier such as water, a relatively short period of storage The soft-sedimentation tolerance is even 1.5-2.0 lbs. , Respectively. In other words, the lower the time-dependent SSR for a given slurry, the better the agglomeration or agglomerated aging prevention, performance, stable storage, slurry suspension retention, and reproducibility and reproducibility of the original slurry suspension after long-term storage .

Because the present invention relates to aqueous, non-aqueous and semi-aqueous media, long-term contact of the composition of the present invention with metals such as carbon steel, iron, spring steel, etc. typical of wire saws, metal wrap wrappers, This can corrode or rust. Therefore, corrosion inhibitors can be added to the carrier composition of the present invention to inhibit or eliminate metal corrosion if necessary. Appropriate inhibitors should not cause bubbles and should not compromise the ability of the compositions of the present invention to provide long term stable abrasive or solid suspensions, or may impair the viscosity, rheology or uniformity of the carrier composition and the abrasive or solid suspensions associated therewith Nor should it.

Examples of suitable corrosion inhibitors that may be added to the aqueous and semi-aqueous carriers of the present invention include, but are not limited to, neutralized carboxylic acids using aliphatic and aromatic carboxylic acids, alkanolamines (i.e., diethanolamine, monoethanolamine, Tetra-alkyl ammonium hydroxides, other similar non-metal hydroxide bases, alkyl or aromatic amines or other Bronsted bases. Other metal non-woven inhibitors also known in the art such as commercially available long chain modified carboxylates such as DeForest DeCore-APCI-95, DeTrope CA-100 and the like may also be included. Another example of a known corrosion inhibitor that is equally suitable for corrosion prevention or inhibition of metals used in the CMP process (i.e., Al / Cu, Cu, Al / Si, Al / Si / Cu, GaAs, LnP, (I. E., Benzimidazole and alkyl-substituted benzimidazole and the like), thiophene compounds such as thiophene compounds such as thiophene compounds such as thiophene compounds such as thiophene, Sulfolanes, modified polyacrylic acids or polyacrylates, polysaccharides, polyalcohols such as polyvinyl alcohol, and the like, or combinations thereof. In addition, there are also other suitable corrosion inhibitors that function as oxygen adsorbents or scavengers and examples thereof include p-hydroquinone (i.e., p-quinol), polyhydroxyaromatic such as catechol or gallic acid, 8- But are not limited to, quinoline, nitrite, sulfite, ascorbic acid.

For the purposes of the present invention, the selection of corrosion inhibitors is not important as long as these inhibitors meet the performance criteria described above, including:

● Suppress or remove metal corrosion;

● do not cause noticeable bubbles in the carrier or the resulting slurry;

● the suspension carrier does not degrade or interfere with the ability of the slurry to provide long-term stability;

● have no detrimental effect on the viscosity, performance or rheology of the carrier or the resulting gel particles or inert solid suspensions;

• have no detrimental effect on the uniformity or homogeneity of carrier suspensions or gel particles in carriers or inert solid suspensions;

• The slurry is suspended by the gel particles, so that they do not react chemically with inert particles or carrier gel particles or base media.

Some salts formed as a by-product of the reaction for the formation of gel particles suitably increase the ionic strength and increase the sedimentation time of the suspended inert particles and assist the repulsion when the concentration and structure of the resulting salt are appropriate. However, depending on the use of the overall slurry suspension, it may also be advantageous to clean only the formed gel particles in neutralized or partially neutralized basic medium, preferably water in this case, by washing the resulting dissolved salts formed during gel particle formation have.

The following examples provide illustrative descriptions of the practice of the method of the present invention. It should be understood, however, that the embodiments listed below are not intended to limit the full scope of the present invention, as they are various modifications included in the present disclosure in light of the principles of the invention described herein. All percentages referred to herein are by weight unless otherwise specified.

Example 1

A. Preparation of gel particles : Solid tap water aluminum hexadecahydrate was added to the tap water to make the percentage of aluminum sulfate in water to 10.76%. This solution was neutralized to pH 7.7 with a 25% solution of tetramethylammonium hydroxide (TMAH) under continuous mixing for a period of 30 minutes. The resulting Al (OH) ₃ gel particles appeared as a cloudy white suspension. The suspension was then washed three times with water to remove the byproduct salt dissolved in the suspension. The resulting carrier suspension had no or very low ionic properties / properties.

B. Suspension slurry preparation of abrasive particles - The gel particles of Part A were filtered and added to this concentrate of gel particles in an aqueous carrier to give a specific gel-particle concentration. This aqueous suspension was coated with a coating containing -10% gel particles Dried titanium oxide solids were added for a total solids load of 25% for use as a composition. The soft-settling resistance (SSR) and the suspended volume maintenance (SVR) data of this composition are shown in Tables 1 and 2 below.

Table 1 - Formulation data

%  solid
Al ₂ (SO ₄ ) ₃ · 16H ₂ O

g tap g solids equivalent
Al ₂ (SO ₄ ) ₃  g 25%
TMAH

% Abrasive loading

pH 10.8 267.7 32.2 99.25 15 7.69

Table 2 - Viscosity, SSR and SVR  data

% solid
Al ₂ (SO ₄ ) ₃ · 16H ₂ O
At 25 ° C
Viscosity (cP)
Peripheral soft-sedimentation & SVR
50 캜 Soft-settling SVR Day 1 Fourth Day 1 Fourth
10.8 carrier Slurry % SVR SSR % SVR SSR % SVR SSR % SVR SSR 16 74 66 0 42 0 56 0 51 0

The SSR readout for a TiO2 solid suspended slurry " zero " proves to be a good suspension. The peripheral SVR readings at the end of the fourth quarter and the SSR value of " 0 " at all time points measured are consistent with a well " soft-precipitated " suspension.

Example 2

A. Preparation of Gel Particles : Solid aluminum sulfate octadecahydrate was added to tap water to make the aluminum sulfate percentage in water to 15.5%. The solution was continuously mixed with KOH (25% solution in water) to neutralize slowly and uniformly to pH 7.7. These in-situ gel particles appeared as a cloudy suspension of white on the water base.

B. Suspension slurry preparation of abrasive particles - A ~ 48% slurry of abrasive SiC particles having an average particle size of ~ 9-10 [mu] m is suspended in the gel particle carrier prepared in (A) above. The suspension was mixed thoroughly and left in both ambient and high temperature conditions to determine the soft-sedimentation and suspension uniformity characteristics. The formulation, viscosity, soft sedimentation retention (SSR) and suspended volume maintenance (SVR) data are shown in the table below.

Again, after 4 weeks, the SSR and SVR readings proved that they were exceptionally stable particle suspensions. However, SVR is generally expected to be lower at elevated temperatures than for the surrounding analog of the same slurry. In this case, as mentioned above, the SVR represents a stable " soft sedimentation " slurry, but does not represent the expected quantitative or qualitative readings, i.e. " although the SVR may be a qualitative indicator, It does not represent a value that matches the expected ... ".

Table 3 - Viscosity, SSR and SVR  data

% solid
Al ₂ (SO ₄ ) ₃
At 25 ° C
Viscosity (cP)
Peripheral softness of the slurry - Sedimentation & SVR
50 캜 Soft-settling SVR Day 1 Fourth Day 1 Fourth
15.5 carrier Slurry % SVR SSR % SVR SSR % SVR SSR % SVR SSR 29.4 236.5 71 0 58 0 71 0 74 0

Example 3

Solid aluminum sulphate octadecahydrate was added to the tap water to make the aluminum sulphate concentration in water to 15.54%. This solution was neutralized with KOH (25% solution in water) to a pH of 7.7. 48 wt% of SiC particles having an average particle size of ~ 8-9.5 [mu] m is added to this white turbid carrier system. The entire suspended slurry is thoroughly mixed for ~ 5 minutes. Formulation, viscosity, SSR, and SVR data are shown in the following table.

Table 4 - Formulation data

% solid
Al ₂ (SO ₄ ) ₃ · 18H ₂ O

g tap g 0.4M
Al ₂ (SO ₄ ) ₃  g 0.5M
NaOH

pH 15.54 253.37 46.52 146.03 7.73

Instead of aluminum sulfate, zinc sulfate or tin sulfate may be used. The gel formed can be filtered and mixed to be used in different liquid media. Similar results with previous examples were observed with respect to slurry stability. However, in this example, an SVR of 71 after 4 weeks at 50 캜 demonstrates that the slurry is exceptionally stable.

Table 5 - Viscosity, SSR and SVR  data*

% solid
Al ₂ (SO ₄ ) ₃
At 25 ° C
Viscosity (cP)
Peripheral softness of the slurry - Sedimentation & SVR
50 캜 soft-sedimentation SVR of the slurry Day 1 Fourth Day 1 Fourth
15.54 carrier Slurry  SVR SSR SVR SSR SVR SSR  SVR SSR 29.4 236.5 71 0 58 0 71 0 49 0

* SVR is always given as a percentage of the total slurry volume.

An inert salt may be added to provide additional electrostatic repulsion of the particles. In addition, the dissolved salts produced by gel particle formation may be washed with water or a suitable carrier medium solvent to produce a gel particle suspension with little or no ionic character.

Example 4a

A. Preparation of Gel Particles - In this example, a semi-aqueous solvent using diethylene glycol (DEG) was used as a solvent instead of tap water. Since aluminum sulphate is not soluble in DEG, an aqueous solution of aluminum sulphate must be prepared prior to adding DEG. Al (OH) ₃ gel-particles are typically prepared in water, and once formed, these gel particles are added to another solvent such as DEG. In this case, a 0.4 M solution of aluminum sulfate was prepared and neutralized to pH ~ 7.8-8.8 with 25% aqueous solution of TMAH. The gel-particles were in-situ separated from the water medium and then added to DEG to provide a " gel-particle " suspension suitable for suspension of the lapping abrasive. SSR, SVR and viscosity were measured. Soft-Precipitation Test tubes were prepared using 18% zirconium oxide (ZrO ₂ ) instead of SiC. The measurement results are shown in Tables 6 and 7 below.

Table 6 - Formulation data

% solid
Al ₂ (SO ₄ ) ₃ 0.4M Al ₂ (SO ₄ ) ₃ Of DEG
Weight (g) 0.4M Al ₂ (SO ₄ ) ₃
Weight (g)
25% TMAH
Weight (g) pH 0.49 2.03 366.16 7.99 5.84 8.01 0.99 4.12 703.91 30.25 22.09 8.05 1.50 6.28 589.22 39.45 28.83 7.80 2.03 8.5 566.14 52.57 38.42 7.79 2.58 10.77 336.74 40.66 29.20 8.80

* DEG: diethylene glycol

The SSR results in Table 7 demonstrate the presence of a stable suspension at ambient temperature after one week when the starting amount of active Al ₂ (SO ₄ ) ₃ exceeds 2.0%. In this case, SVR = 0.16, which is very " soft-settled " indicating a stable suspension. At 50 캜, even when the AlS level is 0.49%, a stable suspension is produced after one week.

Table 7 - SSR and Extended SSR Data

% activation
 solid
Al ₂ (SO ₄ ) ₃ Viscosity at 25 캜 (cP) Nearby SSR  50 ° C SSR
carrier 18% ZrO ₂  Slurry Day 1 1 parking Day 1 1 parking SSR SSR SSR SSR 0.49 31 212 0 1.16 0 0.21 0.99 49 218 0 1.24 0 0 1.50 27 217 0 1.03 0 0.51 2.03 34 353 0 0.16 0 0 2.58 32 330 0 0 0 0

Example 4b

A. Preparation of Gel Particles -In this example, as shown in Example 4a immediately above, a semi-aqueous solvent using propylene glycol methyl ether (PGME) as solvent instead of tap water was used. Since tin sulphate is not sufficiently soluble in PGME, Sn (OH) ₂ gel particles prior to addition to PGME produce an aqueous solution of the tin sulfate produced therein. In this case, a 0.5 M solution of tin sulfate was prepared and neutralized with sufficient 25% aqueous TMAH to a pH of 7.9. The gel particles were filtered and the gel solids were kept under closed conditions for 4 weeks to maintain the water content in the wet gel solids.

B. Suspension Slurry Preparation of Coated Particles - The wet gel particles were then added to a 2: 1 mixture of PMGE and water to make up 33% of the total mixture. Titanium dioxide was added to the mixture at the same weight as the gel particles to form a coating composition. An appropriate amount of tetramethylammonium sulfate can be added to provide additional jerk reaction force between suspended particles.

Example 4c.

The purpose of the following formulations is to lower the viscosity of the formulation described in Example 4a by diluting the carrier with tap water. The carrier is diluted 25% and 50% with water and the aluminum sulfate concentration between the various dilutions is kept constant. For this example, 50% dilution is shown in the table below. An in-situ-sedimentation test tube was prepared using 18% zirconium oxide (ZrO 2) instead of SiC. The measurement results are shown in Tables 8 and 9.

Table 8 - Formulation data

%  solid Al ₂ (SO ₄ ) ₃ The carrier weight (g) of Example 4a Weight of tap water (g) pH 0.25 140 140 7.77 0.50 140 140 7.86 0.75 140 140 7.63 1.01 140 140 7.71 1.29 140 140 7.61

The SSR results in Table 9 are at least acceptable for the soft-settling characteristics of the ambient temperature slurry when the aluminum sulfate content used to form the " Al (OH) ₃ " in situ gel particles in the aqueous medium is greater than about 0.75% Show the numbers. At 50 캜, the SSR represents a soft-settled slurry after one week when the aluminum sulfate content exceeds 0.50%.

table 9 - Viscosity , SSR and SVR  data

% solid
Al ₂ (SO ₄ ) ₃ Viscosity at 25 캜 (cP) Nearby SSR  50 ° C SSR
carrier 18% ZrO ₂ Using
Slurry Day 1 1 parking Day 1 1 parking SSR SSR SSR SSR 0.25 6 63 0 1.3 0 1.6 0.50 8 73 0 1.5 0 1.16 0.750 10 86 0 0.76 0 0.53 1.01 9 87 0 1.1 0 0.14 1.29 16 185 0 0.73 0 0

This example demonstrates that the content of suspended gel-particles should be sufficient to physically and / or physically interfere with the settling of the levels of abrasive or inert particles contained in the subject slurry. If the " gel-particle " content is below the amount required to adequately prevent abrasive grain agglomeration, aggregation and hard sedimentation, a hard precipitated cake is produced that exhibits significant resistance to penetration and, in a uniform and uniform manner, Or slicks from a brick to a desired shape, surface quality, uniform slicing, cutting, polishing, or wrapping of wafers or sliced disc blankets.

Example 5

The separated gel particles prepared according to Example 2, Step A, were combined with a sufficient amount of PEG200 to obtain a wet gel-particle concentration of ~ 30% wt / wt. Three different dilutions of gel particles were given to the three different dilutions by diluting 25%, 50% and 75% of the carrier suspension with a sufficient amount of water. The overall pH, SSR and SVR variations for this example are shown in Table 10 below. 18% zirconium oxide (ZrO ₂ ) was added to the mixture in accordance with the other embodiments of the present invention and the slurry properties were measured. The measurement results of various dilutions are shown in the following table.

Table 10 - Formulation, SSR & SVR  data*

% Al in the carrier ₂ (OH) ₂ Wet gel particles The carrier weight (g) of Example 4c tap water
Weight (g) % Carrier
Dilution % Gel particles in the diluted carrier pH After 3 weeks, the slurry SSR (SVR)
 (18% ZrO ₂ ) 30 140 140 50 15 7.77 0 (52%) 30 140 46.7 25 22.5 7.86 0 (61%) 30 140 420 75 7.5 7.54 0 (41%)

* SVR is the percentage of total slurry volume.

The described gel particles can basically be formed in situ in the suspension medium or formed outside the final suspension medium, but they can be mixed, exposed or otherwise directly mixed with the suspension medium to form a physicochemical reaction between the formed gel particle and the suspension medium, Are essentially fibrillar or gelatinous particles in which electrostatic interactions or other " combinatorial " mechanisms occur and the resulting gelatinous malleable particles are suspended in the medium.

Example 6

A. Preparation of Gel Particles - In this example, a non-aqueous solvent using polyethylene glycol (PEG-200) was used instead of using an aqueous solvent. In addition, instead of the metal hydroxide prepared as " in situ " as suspension gel-particles, a partially neutralized organic polymer is used to produce a suspended " gel-particle " in a non-aqueous PEG-200 solvent.

B. Suspension slurry preparation of abrasive particles - Partial neutralization of the copolymer of acrylic acid and maleic acid with a final molecular weight > 3000 D to form suspended gel-particles. The polymer was initially purchased as a 50/50 (wt / wt) aqueous solution and added to the suspended carrier PEG-200 to form a " solution " of clear to slightly turbid copolymeric acid. This polymeric acid is partially neutralized with the amino-hydroxide base until sufficient " gel-particles " are formed in the PEG suspension medium at a concentration sufficient to suspend ~ 47% SiC abrasive on a wt / .

table 11 - Formulation  data

% Acrylic polymer " gel-particles "
(# 11383) g PEG-200 g amino-
hydroxide
Base Carrier viscosity
cP pH wt / wt%
abrasive
loading Slurry
Viscosity
cP 0.9-1.0 446 13 73 5.3 47.5 300-320

table 12 - Viscosity , SSR and SVR  data

%
Gel particle At 25 ° C
Viscosity (cP) Peripheral soft-sedimentation & SVR 50 ℃ Soft - Precipitation & SVR Day 1 4 parking Day 1 4 parking 0.9-1.0 carrier Slurry % SVR SSR % SVR SSR % SVR SSR % SVR SSR 74 ~ 310 87 0 61 0 79 0 51 0

It should be understood that the gel particles are not considered to be emulsions, sols or gels. This is a pronounced " gelatinous " particle that actually contains some of the molecules of the liquid medium that are formed using the above or other mechanisms to form the gelatinous particles. The gel particles are partially solid but not suspended liquids as in the case of emulsions. The gel particles for the purposes of the present invention have common properties regardless of the actual gel particle chemistry or the difference in mechanism in which it is formed.

A gel particle is a distinct and differentiated molecule and a physical structure that have distinct and independent distinct properties from the overall medium formed by all means used, implemented or utilized to form the " gel particle ". The gel particles can be formed in very different suspensions or carrier media using compounds, polymers, oligomers, organic or inorganic materials that do not have similar properties other than the typical properties to the resulting " gel particles ".

Describing this in a different way, the resulting particles exhibit similar characteristics regardless of the different media in which they are formed, examples of which include:

1) Highly ionic organic suspended polymer particles that are significantly different from the PEG " glycol " medium in which it originally formed, both in terms of physical, structural, molecular and &

2) Very low ionic, inorganic suspended non-polymeric particles that are significantly different from the " water-based " medium in which it originally formed, both in terms of physical, structural, molecular and &

With respect to the two embodiments just described above, these are two very different " molecular species " of gel particles formed in significantly different media with similar formation steps as described below:

a) The gel particles are prepared using a similar method;

b) gel particles are " in-situ " produced in their suspension medium;

c) The gel particles are generated within a distinct and distinct molecule of the molecule present in a very different molecular environment of the medium in which they are made;

d) the gel particles have a density somewhat greater than the density of the medium in which they are formed;

e) The gel particles may be in the form of, for example, mechanical, secondary (i.e., intermolecular and intramolecular charge distribution effects (bi-polar), hydrogen bonding or van der Waals forces) Effectively and efficiently suspend inert particles by particle interactions, physical interference, density differences, and electrostatic charge contributions (at repulsive forces);

f) The gel particles are prepared by chemical or chemical interaction with other molecules in distinct distinct " field " media in which they are formed.

These gel-particles have characteristics or properties that are very similar to and different from other forms, regardless of the medium in which they are formed, or regardless of the components that form the final gel-particle, examples of which include gels The particles are always spotted in a carrier medium having different molecular, stereoregular, rheological, and physical characteristics different from the gel-particle itself. Gel particles (e.g., some polysaccharides) initially formed outside the final carrier medium may be exposed to the carrier for an appropriate period of time, interact with the carrier, mix or react to form the final gel particles. Thus, it can be said that the final gel particles are still formed in situ in the carrier medium. The gel particles always have somewhat greater density than the medium in which they are formed because they tend to contain a portion of the medium in their structure and settle over time at the bottom of the container. The formed gel particles are distinguished from the medium in which they are formed, in terms of physical, stereolithographic, structural and visual conditions. The gel particles have a measurable size and they have a separate physical entity from the carrier medium in which they are formed and suspended. The gel particles are malleable, have " soft " and flexible entities and are mechanically attached to other inert media in the suspension medium to form a kind of cushion around the inert particles, . The gel particles contain carrier medium molecules in which they are formed in the gel-particle itself. Although the size is " micro ", gel particles

 - contains the molecules of the carrier medium formed in the gel-party itself. Although the size is "micro", gel particles can vary greatly in physical structure and size from ~ 2-3 μm to 500 μm, and can be larger depending on the size of the molecule or polymer component. The formed gel particles are not emulsions, sols, gels or soluble particles, and are separate semi-gelatinous particles of the substance and environment, even though they contain molecules of the carrier medium, but completely distinct and distinct from the carrier medium. Once formed, the gel particles no longer react with the medium in which they are formed. It contains a carrier molecule inside it, but no more chemical reaction with the carrier medium. Although the gel particles of the present invention are neither emulsions nor defined emulsion characteristics, they are believed to be " semi-solid " particles that share the characteristics of solid particles, gels and emulsions. However, they do not fit anywhere in these categories.

As the suspended particles, the gel-particles are predominant mainly in the condition that the carrier molecules in the particles are kept intact. If dried or " evaporated " or removal of the carrier medium molecules from the gel particles, the suspension properties of the particles fall and the " dried " particles no longer exhibit abrasive or inert particle suspension properties.

There are many examples of gel particles that satisfy the properties and characteristics of the present invention. These potential gel-particle materials are divided into several groups that can be described as follows:

a) alkaline earth metal hydroxides and oxide-hydrates, i.e. Mg (OH) ₂ ; MgO-x H ₂ 0);

b) In water or other caustic media using Bronsted or non-Bronsted bases to neutralize the in situ salts of Fe, Cr, Al, Zn, Cu, Ni etc. in water or other caustic media An alkaline neutralized salt of a transition metal wherein the end product formed in situ is a " hydrated " or carrier immersed hydroxide of a metal which may also be referred to as a hydrous-oxide;

c) silicates, ortho-silicates and certain poly-silicates;

d) synthetic and natural modified starches (i.e., corn starch and others)

e) Non-limiting examples include: cellulose derivatives such as hydroxy cellulose, hydroxypropyl cellulose, methyl carboxymethyl cellulose, acetyl cellulose;

f) a polysaccharide which is formed outside the suspension medium, but which is "crushed" into pronounced gelatinous particles after prolonged mixing with the suspended medium and which is then ground into gel-particles which can act as suspended particles and re-suspended in the carrier medium, Non-limiting examples thereof include guar, guar gum, agar, agar-guar mixture, carrageenan, pectin, gellan gum, alginate and metal alginate (calcium alginate), plant-derived polysaccharides and mixtures of these substances.

g) Polymer electrolytes in nonionic polar organic carriers include: sulfonated polystyrene (PSS), polyacrylic acid, methacrylic acid, maleic acid or copolymers thereof (neutralized or partially neutralized) (PAA), ammonium poly (methacrylate) (APMA), polyester amides and polyamines, poly- (amino acid) polymer electrolytes such as poly (L-aspartic acid) PGA) and poly (L-lysine) (PLL).

&Quot; Gel particles " for application in connection with the present invention, along with common features and properties independent of the formation mechanism or origin, include many common properties, behaviors, and characteristic threads that together bind the vast variety of structures, compounds, Lt; / RTI &gt; All " gel particles &quot; defined and described in the above examples, regardless of their formation mechanism or origin, have the same common performance and operating characteristics required for the above-mentioned useful applications.

Polysaccharides have been used as coating compositions in aqueous carriers. One such example of coating composition formation is initiated by suspending 5 g of the selected pure polysaccharide-agar and guar gum in 100 ml of distilled water. The suspension was stirred for 24 hours at 500 rpm using a magnetic stirrer. The obtained expanded lumps were spread on an enamel tray and dried at 40 DEG C for 72 hours. The dried product was disposed on a tray and comminuted in a glass mortar to obtain coarse, non-free flowing heterogeneous particles of the treated polysaccharide-treated agar and treated guar gum. The treated polysaccharides were then co-milled with mannitol in a glass mortar bowl at a ratio of 1: 1 and passed through a # 22 sieve to obtain denatured polysaccharide-co-milled agar and co-milled guar gums. The resulting product was then used as a gelatin coating for pharmaceuticals for human consumption. This example suggests that the gel particles can be made by other means than simply mixing the appropriate composition in the liquid medium, while still retaining the properties and characteristics described in the present invention.

The polysaccharide is also used as an alternative to concentrate the water used to maintain the open trench and to form particles to aid in the structure of the foundation wall, while also preventing water from moving the trenches from the inner collapse into the soil Has come. When added to aqueous polysaccharides such as starches, guar, carboxymethylcellulose, beet pulp derivatives and hydroxyethylcellulose with suitable viscosity and solvent properties, a thick gelatinous slurry that is not rapidly converted to solution is produced. Polysaccharide polymers have been found to have a longer solvation time when added to water as a powder or as an oil-based slurry. This is an example of another polymer used as a powder or organic slurry for the formation of gel-particles for use in key carrier systems.

Polymer electrolytes are "dipole" charged polymers that can stabilize (or destabilize) the colloidal emulsion through electrostatic interaction. The effectiveness of the polymer electrolyte depends on molecular weight, pH, solvent polarity, ionic strength and hydrophilic-lipophilic balance. The polymer electrolyte consists of positive or negative charged repeating units. The polymer electrolyte is charged through dissociation of the monomer side chain group. If a greater number of monomer side groups are dissociated, the resulting charge becomes larger. The charge of the polymer causes the polymer electrolyte to be classified as positive (cationic) or negatively charged (negative). The thickness of the polymer electrolyte layer is determined by the charge level and the ionic strength of the polymer electrolyte. Several examples of useful polymer electrolytes are described above.

Example 7

The gel-particle distribution in the carrier system is also important to maintain the separation between the gel particles and the added abrasive or inert particles. Tests have been devised to determine whether gel-particle dilution alters the effectiveness of the gel particles in preventing agglomeration of the added abrasive or inert particles in the slurry. Aqueous solution having the formed gel particles was prepared. All tests were carried out at ambient temperature, 22 ° C, using a 40 ml copper volume, regardless of dilution. The following Table 13 shows the dilution factor with the suspended volume holding force [SVR] expressed in% of the original suspension of 40 ml in the calibrated container.

Gel particle
Dilution factor Day 1 - [t = 0] * Day 2 Day 21 SVR (ml) originally
% Of suspension SVR (ml) originally
% Of suspension SVR (ml) originally
% Of suspension 3: 1 40 100 28.75 72 27 67.5 5: 1 40 100 20 50 17.5 44 6: 1 40 100 21.25 53 19 47.5 8: 1 40 100 18.75 47 17 42.5 9: 1 40 100 17.5 44 15 37.5 10: 1 40 100 16 40 12.5 31.3

* t = 0 indicates freshly prepared suspension indicating that the SVR is still at 100% and no sediment has yet occurred.

The reduction in SVR over time is only possible if the gel particle density is greater than the density of the medium in which the gel is suspended. Regardless of the dilution level of the gel-particle slurry, the SVR value for all samples decreases over time to reveal the gel-particle density, and the suspended particles are larger than the aqueous suspending medium. In practice, the greatest degree of "soft-sedimentation" of suspended particles and gel-particles occurs during the initial 24 hour period at all gel particle dilution levels.

The foregoing examples refer to all inclusive or complete examples of all materials, compounds, polymers (essentially organic, metallic organics or minerals) that meet the unique "inert particle stabilization / suspension" criteria and the general performance and behavioral characteristics of the features described above. These various materials are otherwise referred to as " gel particles ", which are common but unique properties necessary for long-term stabilization of other inert particles to be precipitated as hard or solid particles agglomerated at the bottom of the carrier system vessel, particles "are the other examples of the same unique concept.

Properties of a particular component of a compound, compound or polymer, regardless of the " gel particle " Regardless of whether the structure is organic, metal-organic or inorganic and whether the gel particles are present in an organic or inorganic or a combined liquid carrier system, all of the above-mentioned components act as suspended particle (s) in the carrier medium or system But are only various examples of the same kind of homogeneous forms of gelatinous material having the required characteristics and characteristics.

It is to be understood that the invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof and that the embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the invention, Are set forth solely by the appended claims rather than by the foregoing description of the invention, and thus the scope of the invention encompasses all variations that may fall within the equivalent range intended to be included herein.

Claims (18)

A method for suspending inert colloidal or non-colloidal abrasive or non-abrasive inert particles in a stable aqueous, semi-aqueous or organic carrier medium, said method comprising the steps of: providing sufficient interference with the settling of said inert particles in said carrier medium To form an in situ formed suspension particle so as to establish an appropriate concentration of suspended particles relative to the inert particles in order to cause the carrier particles to migrate, wherein the carrier medium is different from the inert particles and is at a pH of 4 to 12, By weight of suspended particles selected from the group consisting of alkaline earth metals and transition metal hydroxides, oxyhydroxides, and oxide hydrates which in situ form the suspended particles within the range of from 0.1 to 60% by weight, , A molecule, a three-dimensional array, The rheology and physical structure are significantly different, are denser than the carrier medium, are visually identifiable, have a physical structure distinct from the carrier medium, have measurable size differences in the range of about 2-3 [mu] m to 500 [mu] Resulting in suspended particles exhibiting substantially uniform properties comprising suspended particles but no further reactivity with the carrier medium and containing carrier molecules independent of the formation mechanism or origin of the components, Such as electrostatic repulsion of suspended particles from the inert particles and from themselves, as well as physical attraction between the suspended particles and the inert particles, attraction between the suspended particles and the inert particles to provide proximity for chemical, physical or physicochemical interference, Which is suspended in the carrier medium by one action, How the party will have to prevent aggregation or agglomeration for extended periods of time. The method of claim 1, wherein the suspended particles are formed in a medium separate from the final carrier medium. The method of claim 1, wherein the aqueous carrier medium comprises at least one inert polar solvent. The method of claim 3, wherein the inert polar solvent is selected from the group consisting of a dialkylene glycol, an alkylene glycol, a glycol ether, a polyalkylene glycol, an alkyllactone, N-methylpyrrolidone, an alkylene carbonate, acetonitrile, and dimethylacetamide &Lt; / RTI &gt; The method of claim 1, wherein the suspended particles are gel particles, sol gel particles, and gelatinous precipitates formed from alkaline earth metal or transition metal hydroxides, oxyhydroxides, or oxide hydrates. 6. The method of claim 5, wherein the suspended particles are formed from a member selected from the group consisting of aluminum hydroxide, aluminum oxyhydroxide, zinc hydroxide, copper hydroxide, magnesium hydroxide, and tin hydroxide. The method of claim 1 wherein the suspended particles are neutralized with a Bronsted or non-Bronsted base to neutralize the on-site salts of Fe, Cr, Al, Zn, Cu, Ni, etc. so that the suspended particles are hydrated- Sol gel particles and gelatinous precipitates formed from alkaline neutralized salts of transition metals formed in water or other caustic medium to be used. The method of claim 1, wherein the suspended particles are a cellulose derivative comprising hydroxyl cellulose, hydroxylpropyl cellulose, methyl carboxymethyl cellulose and acetyl cellulose, gel particles formed from modified starches, sol gel particles and gelatinous precipitates . The method according to claim 1, wherein the suspended particles are selected from the group consisting of guar, guar gum, agar, agar-guar mixture, carrageenan, pectin, gellan gum, alginate and metal alginate, plant-derived polysaccharides, Gel particles and gelatinous precipitates formed from the polysaccharide formed in the step (a). The method of claim 1, wherein the suspended particles are selected from the group consisting of sulfonated polystyrene, poly-acrylic acid, methacrylic acid, maleic acid or copolymers thereof, ammonium poly (methacrylate), polyester amides and polyamines and poly- Sol gel particles and gelatinous precipitates formed from a polymer electrolyte formed in a non-ionic or polar carrier medium, including a copolymer of an electrolyte. The method of claim 1, wherein the inert particles suspended are particles of titanium dioxide, silicon carbide, zirconium oxide, silica, cerium oxide, aluminum oxide, silicon nitride, boron carbide, tungsten carbide, diamond, silicon dioxide and dry dye particles &Lt; / RTI &gt; The method of claim 1, comprising a corrosion inhibitor. The method of claim 1, comprising an inert salt to provide additional density difference or electrostatic repulsion between the suspended particles and the inert particles. 14. The method of claim 13, comprising removing the inert salt formed by the formation of suspended particles. A suspension gel particle formed in situ in a stable aqueous, semi-aqueous or organic carrier medium for suspension of inert colloidal or non-colloidal abrasive or non-abrasive inert particles, said suspension gel particles being different from said inert particles The particles are included in an amount ranging from 0.1 to 60% by weight relative to the carrier medium, so as to establish an appropriate concentration of suspended particles relative to the inert particles to cause sufficient interference with the settling of the inert particles in the carrier medium, Suspended gel particles are selected from the group consisting of alkaline earth metal and transition metal hydroxides, oxyhydroxides, and oxide hydrates which in situ form the suspended particles in the carrier medium at a pH of 4 to 12, By formation, the carrier medium can include molecules, stereostructures, rheology and physical Having a physically identifiable and distinct physical structure from the carrier medium, having measurable size differences in the range of about 2-3 [mu] m to 500 [mu] m and having suspended particles formed However, there is no additional reactivity with the carrier medium, resulting in suspension gel particles which exhibit substantially uniform properties including carrier molecules that are independent of the formation mechanism or origin of the components, whereby the inert particles are suspended with the suspended gel particles Such as electrostatic repulsion of suspended particles from the inert particles and themselves, to at least one of such forces as physical attraction between particles, proximity for chemical, physical or physico-chemical interference, attraction between the suspended gel particles and the inert particles, Suspended in a carrier medium such that the inert particles in the carrier medium are suspended &lt; RTI ID = 0.0 &gt;Lt; RTI ID = 0.0 &gt; g. &Lt; / RTI &gt; 16. The method of claim 15, further comprising: providing a flexible, rigid physical entity separate from the carrier medium, the physical entity being mechanically attached to any of the inert particles in the carrier medium to form a cushion around the inert particles, Wherein the suspended gel particles serve to increase the suspension. 16. The suspension gel particle of claim 15, wherein the gel particles are only present under the condition that the gel particles remain in the fully immobilized gel particles with the carrier molecules. 16. The method of claim 15, wherein the alkaline earth metal hydroxide and the oxide hydrate, the alkaline neutralized salt of the transition metal, the silicate, the ortho-silicate and the specific poly-silicate, the modified starch, the cellulose derivative, the polysaccharide and the polymer electrolyte are mixed in the non- Lt; RTI ID = 0.0 &gt; of: &lt; / RTI &gt;