DE2721053A1 - Stable aq. dispersion prodn. from non-alkaline silica - using alpha-methylcellulose strengthened with synthetic resin as thickener - Google Patents
Stable aq. dispersion prodn. from non-alkaline silica - using alpha-methylcellulose strengthened with synthetic resin as thickenerInfo
- Publication number
- DE2721053A1 DE2721053A1 DE19772721053 DE2721053A DE2721053A1 DE 2721053 A1 DE2721053 A1 DE 2721053A1 DE 19772721053 DE19772721053 DE 19772721053 DE 2721053 A DE2721053 A DE 2721053A DE 2721053 A1 DE2721053 A1 DE 2721053A1
- Authority
- DE
- Germany
- Prior art keywords
- dispersion
- thickener
- synthetic resin
- methylcellulose
- stable
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 title claims abstract description 37
- 239000006185 dispersion Substances 0.000 title claims abstract description 31
- 239000000377 silicon dioxide Substances 0.000 title claims abstract description 17
- 239000002562 thickening agent Substances 0.000 title claims abstract description 10
- 229920000609 methyl cellulose Polymers 0.000 title claims abstract description 5
- 239000001923 methylcellulose Substances 0.000 title claims abstract description 5
- 229920003002 synthetic resin Polymers 0.000 title abstract 2
- 239000000057 synthetic resin Substances 0.000 title abstract 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 9
- 238000000034 method Methods 0.000 claims abstract description 8
- 239000012065 filter cake Substances 0.000 claims abstract description 7
- 238000003756 stirring Methods 0.000 claims abstract description 6
- 235000012239 silicon dioxide Nutrition 0.000 claims description 4
- 238000002360 preparation method Methods 0.000 claims description 3
- RMAQACBXLXPBSY-UHFFFAOYSA-N silicic acid Chemical compound O[Si](O)(O)O RMAQACBXLXPBSY-UHFFFAOYSA-N 0.000 claims description 3
- 239000003795 chemical substances by application Substances 0.000 abstract 1
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 5
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 3
- 229910052681 coesite Inorganic materials 0.000 description 3
- 229910052906 cristobalite Inorganic materials 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 238000001556 precipitation Methods 0.000 description 3
- 229910052682 stishovite Inorganic materials 0.000 description 3
- 229910052905 tridymite Inorganic materials 0.000 description 3
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 2
- 239000002253 acid Substances 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- BDAGIHXWWSANSR-UHFFFAOYSA-N methanoic acid Natural products OC=O BDAGIHXWWSANSR-UHFFFAOYSA-N 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 238000004062 sedimentation Methods 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- OSWFIVFLDKOXQC-UHFFFAOYSA-N 4-(3-methoxyphenyl)aniline Chemical compound COC1=CC=CC(C=2C=CC(N)=CC=2)=C1 OSWFIVFLDKOXQC-UHFFFAOYSA-N 0.000 description 1
- -1 Al2 (S04) 3 x 18 H20 Chemical class 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 150000008043 acidic salts Chemical class 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 1
- 239000001913 cellulose Substances 0.000 description 1
- 229920002678 cellulose Polymers 0.000 description 1
- 239000007795 chemical reaction product Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 239000013065 commercial product Substances 0.000 description 1
- 239000012153 distilled water Substances 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 235000019253 formic acid Nutrition 0.000 description 1
- 229910021485 fumed silica Inorganic materials 0.000 description 1
- 230000007062 hydrolysis Effects 0.000 description 1
- 238000006460 hydrolysis reaction Methods 0.000 description 1
- 238000005342 ion exchange Methods 0.000 description 1
- 238000004898 kneading Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 150000007522 mineralic acids Chemical class 0.000 description 1
- 150000007524 organic acids Chemical class 0.000 description 1
- 235000005985 organic acids Nutrition 0.000 description 1
- 239000000123 paper Substances 0.000 description 1
- 239000002510 pyrogen Substances 0.000 description 1
- 239000012748 slip agent Substances 0.000 description 1
- 238000009987 spinning Methods 0.000 description 1
- 230000006641 stabilisation Effects 0.000 description 1
- 238000011105 stabilization Methods 0.000 description 1
- 239000000725 suspension Substances 0.000 description 1
- 239000004753 textile Substances 0.000 description 1
- 230000009974 thixotropic effect Effects 0.000 description 1
- 210000002268 wool Anatomy 0.000 description 1
Classifications
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H27/00—Special paper not otherwise provided for, e.g. made by multi-step processes
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B33/00—Silicon; Compounds thereof
- C01B33/113—Silicon oxides; Hydrates thereof
- C01B33/12—Silica; Hydrates thereof, e.g. lepidoic silicic acid
- C01B33/14—Colloidal silica, e.g. dispersions, gels, sols
- C01B33/141—Preparation of hydrosols or aqueous dispersions
- C01B33/1415—Preparation of hydrosols or aqueous dispersions by suspending finely divided silica in water
- C01B33/1417—Preparation of hydrosols or aqueous dispersions by suspending finely divided silica in water an aqueous dispersion being obtained
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
- C09D17/00—Pigment pastes, e.g. for mixing in paints
- C09D17/004—Pigment pastes, e.g. for mixing in paints containing an inorganic pigment
- C09D17/007—Metal oxide
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H19/00—Coated paper; Coating material
- D21H19/36—Coatings with pigments
- D21H19/38—Coatings with pigments characterised by the pigments
- D21H19/40—Coatings with pigments characterised by the pigments siliceous, e.g. clays
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H5/00—Special paper or cardboard not otherwise provided for
- D21H5/0072—Anti-slip papers
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Dispersion Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Wood Science & Technology (AREA)
- Paper (AREA)
Abstract
Description
Kieselsäuredispersionen werden für viele Einsatzgebiete,Silicic acid dispersions are used for many areas of application,
z.B. für Überzüge auf Photopapieren, zum Spinnen von Wolle und für die schmutzfeste Verbindung von Textilfasern angewandt.e.g. for coatings on photo paper, for spinning wool and for the dirt-resistant connection of textile fibers is used.
Die Herstellung von stabilen Dispersionen aus dispergierten pyrogenen Kieselsäuren ist bereits seit längerem bekannt (US-PS 2 984 629, US-PS 2 951 044), diese weisen jedoch einen alkalischen pH-Wert auf.The production of stable dispersions from dispersed pyrogens Silicas have been known for a long time (US Pat. No. 2,984,629, US Pat. No. 2,951,044), however, these have an alkaline pH.
Wegen der aufwendigen Herstellung der Dispersionen - Einsatz von hochreinem pyrogen hergestelltem SiO2 - bleibt die Anwendung jedoch aufgrund des Preises auf einen kleineren Bereich beschränkt als an und für sich möglich wäre. Der an sich naheliegende wesentlich preiswertere Einsatz von gefällten Kieselsäuren für Dispersionen - sei es in Form eines Filterkuchens, sei es als aus dem Filterkuchen durch geeignete Trocknungsverfahren hergestellte pulverförmige Kieselsäure v scheiterte bisher daran, dass die bekannten Wege, um stabile Dispersionen zu erhalten, entweder, wie die für Kieselsäuresol übliche Ionenaustauschtechnik,überhaupt nicht anwendbar waren, oder aber, wie beim Arbeiten nach den für die Herstellung von Dispersionen aus pyrogenen Kieselsäuren gültigen Prinzipien - unter Stabilisierung im alkalischen Bereich - , nicht zu ausreichend stabilen Dispersionen führten.Because of the complex production of the dispersions - use of high purity Pyrogenically produced SiO2 - however, the application remains due to the price limited to a smaller area than would be possible in and of itself. The in itself Obvious, much cheaper use of precipitated silicas for dispersions - be it in the form of a filter cake, be it as from the filter cake through suitable ones Powdered silica produced by the drying process has so far failed because that the known ways to get stable dispersions, either, like the ion exchange technology customary for silica sol were not applicable at all, or else, as when working according to the for the preparation of dispersions from pyrogenic Silica valid principles - with stabilization in the alkaline range - , did not lead to sufficiently stable dispersions.
So ist aus der US-PS 3715 842 eine Dispersion von Kieselsäurn in HzO bekannt, bei welcherein wasserlösliche3 Cellulosederivat als Verdickungsmittel eingesetzt wird und welche einen p-Wert von mindestens 7 aufweist.For example, US Pat. No. 3,715,842 discloses a dispersion of silica in HzO known in which a water-soluble3 cellulose derivative is used as a thickener and which has a p-value of at least 7.
Alkalische Dispersionen weisen jedoch den Nachteil auf, dass durch den Alkaligehalt die dispergierte Kieselsäure angegriffen bzw. aufgeweicht wird.However, alkaline dispersions have the disadvantage that by the alkali content of the dispersed silica is attacked or softened.
Es wurde nun überraschenderweise gefunden, dass es möglich ist, stabile Dispersionen aus gefällten und aus der wässrigen Fällungssuspension durch Filtration isolierten - und gegebenenfalls getrockneten Kieselsäuren herzustellen, welche nicht alkalisch sind.It has now surprisingly been found that it is possible to produce stable Dispersions of precipitated and of the aqueous precipitation suspension by filtration isolated - and optionally dried silicas to produce, which are not are alkaline.
Gegenstand der Erfindung ist ein Verfahren zur Herstellung einer stabilen Dispersion einer gefällten Kieselsäure in Wasser, welches dadurch gekennzeichnet ist, dass man gefällte Kieselsäure in Wasser gleichmässig verteilt, in dieser Dispersion unter Rühren einen pH-Wert von 1 bis 6, vorzugsweise 2 bis 4, einstellt und die Dispersion durch Zusatz eines Verdickungsmittels in Mengen von 0,001 * bis 1 %, bevorzugt, 0,005 % bis 0,1 %, bezogen auf die Gesamtmenge der Dispersion stabilisiert. Die Kieselsäurekonzentration im Endprodukt kann 0,1 bis zu 30 Gew.-% betragen.The invention relates to a method for producing a stable Dispersion of a precipitated silica in water, which is characterized is that precipitated silica is evenly distributed in water in this dispersion while stirring a pH of 1 to 6, preferably 2 to 4, adjusts and the Dispersion by adding a thickener in amounts of 0.001 * to 1%, preferably, 0.005% to 0.1%, based on the total amount of the dispersion stabilized. The silica concentration in the end product can be 0.1 up to 30% by weight.
Während höhere Zusätze die Stabilität der Dispersion beeinträchtigen, sind niedrigere Si02-Konzentrationen ohne Einschränkungen möglich. In einer bevorzugten Ausführungsform kann die erfindungsgemäss erhaltene Kieselsäuredispersion eine Konzentration an Kieselsäure von 15 bis 25 Gew.-% aufweisen.While higher additives impair the stability of the dispersion, lower Si02 concentrations are possible without restrictions. In a preferred Embodiment, the silica dispersion obtained according to the invention can have a concentration of silica from 15 to 25% by weight.
In einer bevorzugten Ausführungsform der Erfindung kann man die gefällte Kieselsäure in Form ihres Filterkuchens mit einem Wassergehalt von ca. 80 % einsetzen. Dies kann so geschehen, damm man den Filterkuchen unter Kneten durch Zusatz von Säure verflüssigt, auf einen pH-Wert von 1 bis 6, bevorzugt auf einen pH-Wert von 2 bis 4, einstellt und dann das Verdickungsmittel hinzufügt. Als Verdickwigsmittel kann man kunstharzverstärlete cc -'-lethylcellulose vcrwenden.In a preferred embodiment of the invention, the precipitated Use silica in the form of its filter cake with a water content of approx. 80%. This can be done by adding the filter cake while kneading Liquefied acid to a pH of 1 to 6, preferably to a pH of 2 to 4, then add the thickener. As a thickener synthetic resin-reinforced cc -lethylcellulose can be used.
Als Säuren können anorganische Säuren, wie z.B. Schwefelsäure oder Phosphorsäure; organische Säuren, Wie z.B.Inorganic acids such as sulfuric acid or Phosphoric acid; organic acids, e.g.
Ameisensäure oder Esssigsäure zugesetzt werden. Auch durch Hydrolyse sauer wirkende Salze, wie z.B. Al2(S04)3 x 18 H20 können zur Einstellung des erfindungsgemässen pH-Wertes verwendet werden.Formic acid or acetic acid can be added. Also by hydrolysis acidic salts, such as Al2 (S04) 3 x 18 H20, can be used to adjust the pH value can be used.
Die erfindungsgemäss erhaltenen Dispersionen können z.B. als Antirutschmittel für Kartonagen eingesetzt werden.The dispersions obtained according to the invention can be used, for example, as anti-slip agents can be used for cardboard boxes.
Durch den Zusatz der Verdickungsmittel in sehr niedrigen Konzentrationen von unter 1 % - bezogen auf die fertige Dispersion - bildet sich ein gelartiger Zustand aus, der ein Sedimentieren der sauren, zunächst nur durch mechanische Mittel dispergierten Kieselsäureteilchen unterbindet. Aufgrund einer ebenfalls völlig unerwarteten Thixotrophie des Gels ist die Dispersion jederzeit durch einfaches Rühren wieder in einen dünnflüssigen zur direkten Anwendung geeigneten Zustand zu überführen. Da sich der gelartige Zustand erst nach ca. 24 - 28 Stunden wieder ausbildet, verharrt die Dispersion ausreichend lange im verarbeitungsfähigen Zustand. Der sich nach 24 - 28 Stunden wieder ausbildende gelartige Zustand verhindert auf der anderen Seite wirkungsvoll jede Sedimentation.By adding the thickener in very low concentrations of less than 1% - based on the finished dispersion - a gel-like form is formed Condition from a sedimentation of the acid, initially only by mechanical means prevents dispersed silica particles. Because of a completely unexpected one The gel is thixotropic at any time by simply stirring the dispersion again to be converted into a thin liquid state suitable for direct use. Since the gel-like state only develops again after approx. 24 - 28 hours, it persists the dispersion for a sufficiently long time in the workable state. The after 24 - 28 hours prevents on the other from developing gel-like condition again Side effectively any sedimentation.
Das erfindurigsgemässe Verfahren wird anhand der folgenden Beispiele näher erläutert und beschrieben: Beispiel 1: 1,1 kg Fällungskieselsäurefilterkuchen wird mit 0,36 kg (= 0,032 %) konzentrierter Schwefelsäure verknetet bis eine rührfähige Mischung entsteht. Die rührfähige Mischung (z.B.The method according to the invention is illustrated by the following examples explained and described in more detail: Example 1: 1.1 kg of precipitated silica filter cake is kneaded with 0.36 kg (= 0.032%) concentrated sulfuric acid until it is stirrable Mixture is created. The stirrable mixture (e.g.
aus Wasser, SiO2 und H2S04 wird mit einem Hochleistungsrühr gerät (Ultraturax, Fa. Janke ur£d Kenkel) anschliessend 10 Minuten unter Kühlung homogenisiert. 2 Minuten vor Ende des Rührvorganges wird eine Menge von 0,12 g (0,011 %) einer kunstharzverstärkenden t-Methylcellulose (Handelsprodukt Glutolin 77 der Fa. Kalle, Wiesbaden) hinzugegeben und mit dem Hochleistungsrührgerät eingearbeitet.from water, SiO2 and H2S04 is made with a high-performance stirrer (Ultraturax, Janke ur £ d Kenkel) then 10 minutes under Cooling homogenized. 2 minutes before the end of the stirring process, an amount of 0.12 g (0.011%) of a synthetic resin-reinforcing t-methyl cellulose (commercial product Glutolin 77 from Kalle, Wiesbaden) was added and with a high-performance mixer incorporated.
Die erhaltene Dispersion weist einen Feststoffgehalt von 200 g/l, einen pH-Wert von 3,5 und eine Viskosität im ungelierten Zustand von 1,3 bis 1,50 E auf.The dispersion obtained has a solids content of 200 g / l, a pH of 3.5 and a viscosity in the ungelled state of 1.3 to 1.50 E on.
Noch nach einem Zeitraum von 1 Jahr hat sich kein Niederschlag gebildet.After a period of 1 year, no precipitation has formed.
Beispiel 2: 225 g einer gefällten und anschliessend auf geeignete Weise getrocknete pulverförmigen Kieselsäure VN 3 (Hersteller Degussa) wurden zunächst in 900 ml destilliertem Wasser verteilt und anschliessend mit einem Hochleistungsrührgerät (z.B. Ultraturrax, Fa. Janke und Kunkel) eine Minute homogenisiert. In die so hergestellte Rohdispersion wird zur Viskositätserniedrigung eine Menge von 0,36 g konzentrierte Schwefelsäure gegeben und anschliessend unter Kühung weitere 10 Minuten eingearbeitet. 2 Minuten vor Ende des Rührvorganges wird eine Menge von 0,12 g einer kunstharzverstärkten t -Methylcellulose hinzugegeben und mit dem Hochleistungsrührgerät eingearbeitet.Example 2: 225 g of a precipitated and then suitable Wise dried powdered silica VN 3 (manufacturer Degussa) were initially Distributed in 900 ml of distilled water and then with a high-performance mixer (e.g. Ultraturrax, Janke and Kunkel) homogenized for one minute. In the one made in this way An amount of 0.36 g is concentrated to reduce the viscosity of the crude dispersion Given sulfuric acid and then incorporated with cooling for a further 10 minutes. 2 minutes before the end of the stirring process, 0.12 g of a synthetic resin-reinforced t -Methylcellulose was added and worked in with the high-performance mixer.
Die erhaltene Dispersion hat einen Foststoffgehalt von 200 g/l und einen pH-Wert von 3,5; ihre Viskosität im ungelierten Zustand beträgt 1,3 - 1,5 E.The dispersion obtained has a solids content of 200 g / l and a pH of 3.5; its viscosity in the ungelled state is 1.3-1.5 E.
Noch nach einem Zeitrauni von 1 Jahr hat sich kein Niederschlag gebildet.After a period of 1 year, no precipitation has formed.
Claims (3)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19772721053 DE2721053C2 (en) | 1977-05-11 | 1977-05-11 | Process for the preparation of a stable dispersion of a precipitated silica in water |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19772721053 DE2721053C2 (en) | 1977-05-11 | 1977-05-11 | Process for the preparation of a stable dispersion of a precipitated silica in water |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| DE2721053A1 true DE2721053A1 (en) | 1978-11-23 |
| DE2721053C2 DE2721053C2 (en) | 1981-10-08 |
Family
ID=6008545
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| DE19772721053 Expired DE2721053C2 (en) | 1977-05-11 | 1977-05-11 | Process for the preparation of a stable dispersion of a precipitated silica in water |
Country Status (1)
| Country | Link |
|---|---|
| DE (1) | DE2721053C2 (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2627176A1 (en) * | 1988-02-11 | 1989-08-18 | Rhone Poulenc Chimie | AQUEOUS STABLE PRECIPITATION SILICA SUSPENSION |
| WO1990003330A3 (en) * | 1988-09-22 | 1990-04-19 | Ppg Industries Inc | High solids aqueous silica slurry |
| EP0377301A1 (en) * | 1988-12-22 | 1990-07-11 | Unilever Plc | Stable silica suspensions |
| US5232724A (en) * | 1988-12-22 | 1993-08-03 | Unilever Patent Holdings B.V. | Method for stabilizing alcoholic beverages using an aqueous suspension containing amorphous silica |
| WO1995017105A1 (en) * | 1993-12-23 | 1995-06-29 | Lopez Acedo Fernandez Shaw Cec | Liquid filter intended to retain the toxic substances contained in tobacco, process for its preparation and applications |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3715842A (en) * | 1970-07-02 | 1973-02-13 | Tizon Chem Corp | Silica polishing compositions having a reduced tendency to scratch silicon and germanium surfaces |
-
1977
- 1977-05-11 DE DE19772721053 patent/DE2721053C2/en not_active Expired
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3715842A (en) * | 1970-07-02 | 1973-02-13 | Tizon Chem Corp | Silica polishing compositions having a reduced tendency to scratch silicon and germanium surfaces |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2627176A1 (en) * | 1988-02-11 | 1989-08-18 | Rhone Poulenc Chimie | AQUEOUS STABLE PRECIPITATION SILICA SUSPENSION |
| EP0329509A1 (en) * | 1988-02-11 | 1989-08-23 | Rhone-Poulenc Chimie | Stable, aqueous suspension of precipitated silica |
| AU626287B2 (en) * | 1988-02-11 | 1992-07-30 | Rhone-Poulenc Chimie | Stable aqueous suspension of precipitation silica |
| WO1990003330A3 (en) * | 1988-09-22 | 1990-04-19 | Ppg Industries Inc | High solids aqueous silica slurry |
| EP0377301A1 (en) * | 1988-12-22 | 1990-07-11 | Unilever Plc | Stable silica suspensions |
| US5102676A (en) * | 1988-12-22 | 1992-04-07 | Unilever Patent Holdings B.V. | Stable suspensions for filtering beer |
| US5232724A (en) * | 1988-12-22 | 1993-08-03 | Unilever Patent Holdings B.V. | Method for stabilizing alcoholic beverages using an aqueous suspension containing amorphous silica |
| WO1995017105A1 (en) * | 1993-12-23 | 1995-06-29 | Lopez Acedo Fernandez Shaw Cec | Liquid filter intended to retain the toxic substances contained in tobacco, process for its preparation and applications |
Also Published As
| Publication number | Publication date |
|---|---|
| DE2721053C2 (en) | 1981-10-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| DE69531785T2 (en) | CONCENTRATED FILLING SILICON SUSPENSION, METHOD FOR THE PRODUCTION AND USE OF THIS SUSPENSION | |
| DE68909113T2 (en) | Absorbing precipitated silica and composition based on this silica. | |
| DE69004482T2 (en) | Silica beads, process for their preparation and their use for reinforcing elastomers. | |
| DE4006393A1 (en) | AQUEOUS COLLOIDAL DISPERSION OF GAS PHASE-MADE SILICON DIOXYDE WITHOUT STABILIZER | |
| DE4006392A1 (en) | AQUEOUS COLLOIDAL DISPERSION FROM GAS PHASE-BASED SILICON DIOXIDE, FROM AN ACID AND FROM A STABILIZER, AND A METHOD FOR THEIR PRODUCTION | |
| AT412289B (en) | METHOD FOR PRODUCING PAPER | |
| EP0518175B1 (en) | Preparation of a neutral titanium oxide sol | |
| DE2721053A1 (en) | Stable aq. dispersion prodn. from non-alkaline silica - using alpha-methylcellulose strengthened with synthetic resin as thickener | |
| EP0280077B1 (en) | Tooth-pastes and cleansing agent for tooth-pastes based on dicalciumphosphat-dihydrat and a preparation method for such a cleansing-agent | |
| DE1442656C3 (en) | Process for the production of a stable dispersion of pyrogenically obtained finely divided silicon dioxide | |
| CH493272A (en) | Process for the production of marketable, colloidal solutions of finely divided silicon dioxide or mixed oxides containing it | |
| DE2337374C2 (en) | ||
| DE714434C (en) | Process for the production of homogeneous cellulose solutions in mineral acids or their mixtures for the production of rayon, films, tapes and similar products | |
| EP0166185A1 (en) | Process for the preparation of cupric hydroxide | |
| DE867543C (en) | Process for the production of powdered silica | |
| CH164831A (en) | Process for the preparation of water-soluble substances containing the phosphoric acid radical by digesting raw materials containing calcium phosphate. | |
| DE102004021515B4 (en) | Process for the preparation of hollow microspheres of borosilicate | |
| DE102014101709A1 (en) | Process for the preparation of aerogels | |
| DE720109C (en) | Process for the production of a highly concentrated solution of a stable, high viscosity, partially saponified cellulose acetate | |
| DE2109306C3 (en) | Process for the preparation of compositions containing colloidal chrysotile asbestos | |
| DE536546C (en) | Production of active silica with large pores | |
| AT256037B (en) | Process for the production of finely divided silicon dioxide by reacting alkali silicate solutions with acid solutions | |
| DE809805C (en) | Process for the production of acetyl celluloses | |
| DE708805C (en) | Process for the production of lecithin solutions that remain clear | |
| DE894160C (en) | Process for the production of products which consist of or contain rubber from aqueous rubber dispersions |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| OD | Request for examination | ||
| OGA | New person/name/address of the applicant | ||
| D2 | Grant after examination | ||
| 8339 | Ceased/non-payment of the annual fee |