[go: up one dir, main page]

US1986001A - Manufacture of plasters - Google Patents

Manufacture of plasters Download PDF

Info

Publication number
US1986001A
US1986001A US479931A US47993130A US1986001A US 1986001 A US1986001 A US 1986001A US 479931 A US479931 A US 479931A US 47993130 A US47993130 A US 47993130A US 1986001 A US1986001 A US 1986001A
Authority
US
United States
Prior art keywords
plaster
anhydrite
plasters
component consists
accelerated
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.)
Expired - Lifetime
Application number
US479931A
Inventor
Lefebure Victor
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Application granted granted Critical
Publication of US1986001A publication Critical patent/US1986001A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C04CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04BLIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B11/00Calcium sulfate cements
    • C04B11/002Mixtures of different CaSO4-modifications, e.g. plaster of Paris and anhydrite, used as cements

Definitions

  • a mixture off on "part of mediums'etting hard wall plaster "with a-s'etfof ahout one liburg'miz ied 'wi'th s of aiihydrite pieaer arrangea toset about one hour will set to" a hard-'iriass'a-lmost n two or thr'ee minutes, varying w h "oofiditi ns such-as temperature andexce'ss' water; Although this observed efieet of speed-has been found true'ingenei'alin the adini x tiires" of anhyeme 61'" ae eeie'rate'd anhydrite with" hernihydrated plaste'rs t ere will be some forms of the latter in which" the increase of speed; although substantial r'i'iay not: beso great.
  • the rfiethod can employed to i crease the setting speed o-f *slow wall plasters or; by heavy'lo' "ding withanhydriteyto reduoeith'e speed ulding -plasters, tln'is prGidlliiing' plas- I a1 or 'better duality thar'istandard t substantially ldwercbst, thematerm simply ground kminei alanhydr ite; or 'the latter with atrace o'i lbw -pjried batal yst.
  • the standard liehti'hydrated g eammanat has aweryflli ck se 'm ms form it is' used formouldifig asifplajster br rris;
  • the slowest mixtures are obtained by heavy dilution with the unaccelerated anhydrite. This gives a very satisfactory and easily standardized method of controlling speed of set without the addition of undesirable organic substances, or without loading with high percentages of inorganic accelerators.
  • the set mass from the mixture when using the accelerated anhydrite is as hard and strong as (in fact,almost invariably harder and stronger than) the normal hemihydrated plaster in the mixture when used alone.
  • the resultant set'mass is not always harder and stronger, but makes as good practical plaster up to very high dilution.
  • the anhydrite content of the mixture im: proves the final product in the direction of the properties of anhydrite plasters, not only as regards hardness and strength, but as regards a surface more suitable for rapid after decoration.
  • the normal methodof producing very rapid anhydrite plasters is to increase the setting or accelerating agent percentage, which increases cost.
  • the mixtures according to the present invention enable-very fast plasters up to a practically instantaneous set, to be made at lower cost, employing in the combinationeither anhydrite alone or anhydrite with very small percentages of setting agent.
  • Another advantage which has been observed is that for practical use mixtures can be obtained which have a higher sandcarrying capacity than the two components, certainly as regards the initial strength of the mass as distinguished from the ultimate strength, which is a point of considerable practical importance.
  • Example 1 A plaster suitable for wall surfaces in normal building operations made by the mixture of one part of standard retarded hemihydrated plaster, having afirm set of about 60 minutes, with 9 parts of anhydrite containing 0.2% of potassium sulphate and zinc sulphate salts in molecular proportions, having itself a firm set of about hours.
  • This resultant mixed wall plaster has a firm set of about60 minutes, being of average speed for wall work.
  • Example 2 Casting or-moulding plaster A plaster suitable for very quick work, made by mixing one part by volume of a standard retarded hemihydrated plaster with 4 parts by volume of anhydrite containing 2% of potassium sulphate and zinc sulphate mixed salts in molecular proportions.
  • a plaster composition consisting of two components only in which the first component consists of unburnt natural anhydrite (CaSO4), and the second component consists of burnt gypsum (CaSO4. /2I'I2O), in the proportions of 1-9 parts of the first component to 1 part of the second.
  • a plaster composition consisting of two components only in which the first component consists of accelerated unburnt natural anhydrite (CaSOr), and the second component consists of burnt gypsum (CaSO4. /2H2O).
  • a plaster composition consisting of two components only in which the first component consists of unburnt natural anhydrite (CaSOq), and the second component consists of a retarded CaSOl. /2H2O wall plaster.
  • a plaster composition consisting of two components only in which the first component consists of accelerated unburnt natural anhydrite (C3804) and the second component consists of a retarded CaSO4. /2HzO wall plaster.
  • a plaster composition consisting of two components only in which the first component consists of accelerated unburnt natural anhydrite (C3804), and the second component consists of a retarded CaSOM/ I-IzO wall plaster.
  • a plaster composition consisting of two components only having a firm set of about 1 hour
  • the first component consists of unburnt natural anhydrite containing about 0.2% of potassium sulphate and zinc sulphate in molecular proportions, having a firm set of about 5 hours,
  • the second component consists of a retarded CLsO4. /gH2O wall plaster having a firm set of about 1 hour.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Ceramic Engineering (AREA)
  • Materials Engineering (AREA)
  • Structural Engineering (AREA)
  • Organic Chemistry (AREA)
  • Building Environments (AREA)
  • Curing Cements, Concrete, And Artificial Stone (AREA)

Description

Patented Jan. 1 1935 MANUFACTURE oF'r'LAs'TERs I VictoriLef ebure, Hampstead, London," England I -'No "Drawing. I Application September 5,, 1930, Serial No.-479,931. Great BritainOctober 1i rn my UQS.AQPatentSpecificatiOn'No. 1,879,877
it is sli otvnf how natural fanhydrite, formerl; 1'3, waste material of no value for plaster making, canhe converted into 'a good plaster. Il'1a\ e now found foth er ways of making new" form s of anhydri'te plasters: whieh have 'distinct cdmn'iercaradvamages. i I V According to thisinventic in l provide a; process offiiianufacture "or anhydrite plasters 'whichconsists' in 'm'ixing 'z'agnhydrite"with thehemihydrated form-of calcium-sulphate, CaSO4 AzHzO, which is the standard chemicalcomposition df plasterpf Paris.
luted with fillers such as powdered silica or gy sum the mass-after 'settingj 'lieconies correspond ni'gly weak "and soft according to'-the amount of dilution, whieh 'resultfwould he expected" the dilution or demerits and binders withinerti fillers in general. 'But ifground anhydritefhe employed instead of fillerssuch as the above it id'o'snot act as a diluent but for a git en concentration gives a niuch harder and stronger mass.
The following example illustrates tion, the parts' beingfbyfvoluinel "Example-One part of plaster of'Par'isis mixed with'eight parts powderedsilica; theresuIting mass after settingwith water in the usualway, is very weak and soft, quite unusableas a plas-' ter. One part of the same plaster offParisand eight-parts ground anhi drite, after, treating'in theisanie manner with water, give a mass as hard and strong as the neat pla'ster swans,
Another important advantagejof the process of manufacture according to this invention is the increase inspeed offsetting; and improvement in properties of standard wallplastersby the additionwof anhydrite, or'of accelerated? anhydri'te. "By the latter I refer to su'chlanhydrit'e-plasters' as a're covered by the patent men s Claims. }(01. 106- 34) steward plasterysuch'-as-plaster of Paris- 9r b t w l-Knew i'lr e 10 qlld hard plasters, containing CaSOU/QHQO-be' "di the inven- In the industryorgamc fretardersf are used to m'ixture will set in'jfrom less than one minjutequp to' fifteenfminutes, much? quicker than eithero the components. For example, a mixture off on "part of mediums'etting hard wall plaster "with a-s'etfof ahout one liburg'miz ied 'wi'th s of aiihydrite pieaer arrangea toset about one hour will set to" a hard-'iriass'a-lmost n two or thr'ee minutes, varying w h "oofiditi ns such-as temperature andexce'ss' water; Although this observed efieet of speed-has been found true'ingenei'alin the adini x tiires" of anhyeme 61'" ae eeie'rate'd anhydrite with" hernihydrated plaste'rs t ere will be some forms of the latter in which" the increase of speed; although substantial r'i'iay not: beso great. f-For' example, in admixtures of aecelerated anhiidrite withKeehes' cemenu-wiiich isaetwneny-a hydratedplaster view 'of'itsdouble ahd l iigher' temperature roasting, the speed inayhe fredu'eed frdm' four hours *downto about 25-1rrlirnll'te's, but notnecessarilyfdownto-one minute, V
Thus 'the rfiethod can employed to i crease the setting speed o-f *slow wall plasters or; by heavy'lo' "ding withanhydriteyto reduoeith'e speed ulding -plasters, tln'is prGidlliiing' plas- I a1 or 'better duality thar'istandard t substantially ldwercbst, thematerm simply ground kminei alanhydr ite; or 'the latter with atrace o'i lbw -pjried batal yst. 'As an example, the standard liehti'hydrated g eammanat has aweryflli ck se 'm ms form it is' used formouldifig asifplajster br rris;
duce the-*spee'd. A ccordingg to'thisinvehtionyit is'poss'ihleto'reducethespeed, making plas; tel suitable for, van purposes ib'y. ad percentages of Hams/ante, such "as, for ex 9 mm bi ri ai t Pari 'lY e tr' rt a: anhydrite, ,I hayefoundthat thequicke st frnixtures, which are almost mstantaneous consist of one volume :of the; hemihydrated vform frgomaloout :one hali 'to three volumesof acceleratedsianhydrite. Atsomepomtsxbetweeni these proe portions, v arying'with' the raw materials; whereas a peak of speed.
The following table gives the variation of speed with admixture employinga standardcommercial retarded hemihydrated plaster and an accelerated anhydrite, both setting individually in about 60 minutes:
Percent Percent standard accelerated Setting time plaster anhydrite Minutes Nil. 100 60 10 90 16 20 80 4 40 60 2% 50 50 l 60 40 2% 80 20 5% 100 60 and the following table gives the variation employing the same standard plaster and non-accelerated anhydrite with a practically indefinite setting time:-
Percent Percent I nonstalralsdtaarrd accelerated Setting time p anhydrite 3 Nil. 100 No practical set. 10 90 15 minutes. 20 80 6 minutes. 40 v 60 6 minutes. 80 20 24 minutes. 100 Nil. 60 minutes.
The slowest mixtures are obtained by heavy dilution with the unaccelerated anhydrite. This gives a very satisfactory and easily standardized method of controlling speed of set without the addition of undesirable organic substances, or without loading with high percentages of inorganic accelerators.
These mixtures have various other advantages besides those mentioned above: First, the set mass from the mixture when using the accelerated anhydrite, is as hard and strong as (in fact,almost invariably harder and stronger than) the normal hemihydrated plaster in the mixture when used alone. In using high percentages of non-accelerated anhydrite the resultant set'mass is not always harder and stronger, but makes as good practical plaster up to very high dilution. Secondly, the anhydrite content of the mixture im: proves the final product in the direction of the properties of anhydrite plasters, not only as regards hardness and strength, but as regards a surface more suitable for rapid after decoration. Thirdly, the normal methodof producing very rapid anhydrite plasters is to increase the setting or accelerating agent percentage, which increases cost. The mixtures according to the present invention, enable-very fast plasters up to a practically instantaneous set, to be made at lower cost, employing in the combinationeither anhydrite alone or anhydrite with very small percentages of setting agent. Another advantage which has been observed is that for practical use mixtures can be obtained which have a higher sandcarrying capacity than the two components, certainly as regards the initial strength of the mass as distinguished from the ultimate strength, which is a point of considerable practical importance.
The manner in which the invention is applicable to various requirements is further illustrated by the following examples, which are by no means limitative of the field of usefulness of the invention.
Example 1 .--WaZZ plaster A plaster suitable for wall surfaces in normal building operations made by the mixture of one part of standard retarded hemihydrated plaster, having afirm set of about 60 minutes, with 9 parts of anhydrite containing 0.2% of potassium sulphate and zinc sulphate salts in molecular proportions, having itself a firm set of about hours. This resultant mixed wall plaster has a firm set of about60 minutes, being of average speed for wall work.
Example 2.,Casting or-moulding plaster A plaster suitable for very quick work, made by mixing one part by volume of a standard retarded hemihydrated plaster with 4 parts by volume of anhydrite containing 2% of potassium sulphate and zinc sulphate mixed salts in molecular proportions.
What I claim and desire to secure by Letters Patent is:- v
1. A plaster composition consisting of two components only in which the first component consists of unburnt natural anhydrite (CaSO4), and the second component consists of burnt gypsum (CaSO4. /2I'I2O), in the proportions of 1-9 parts of the first component to 1 part of the second.
2. A plaster composition consisting of two components only in which the first component consists of accelerated unburnt natural anhydrite (CaSOr), and the second component consists of burnt gypsum (CaSO4. /2H2O).
3. A plaster composition consisting of two components only in which the first component consists of unburnt natural anhydrite (CaSOq), and the second component consists of a retarded CaSOl. /2H2O wall plaster.
4. A plaster composition consisting of two components only in which the first component consists of accelerated unburnt natural anhydrite (C3804) and the second component consists of a retarded CaSO4. /2HzO wall plaster.
5. A plaster composition consisting of two components only in which the first component consists of accelerated unburnt natural anhydrite (C3804), and the second component consists of a retarded CaSOM/ I-IzO wall plaster.
6; A plaster composition consisting of two components only having a firm set of about 1 hour,
in whichthe first component consists of unburnt natural anhydrite containing about 0.2% of potassium sulphate and zinc sulphate in molecular proportions, having a firm set of about 5 hours,
and the second component consists of a retarded CLsO4. /gH2O wall plaster having a firm set of about 1 hour.
VICTOR LEFEBURE.
US479931A 1929-10-10 1930-09-05 Manufacture of plasters Expired - Lifetime US1986001A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB1986001X 1929-10-10

Publications (1)

Publication Number Publication Date
US1986001A true US1986001A (en) 1935-01-01

Family

ID=10895340

Family Applications (1)

Application Number Title Priority Date Filing Date
US479931A Expired - Lifetime US1986001A (en) 1929-10-10 1930-09-05 Manufacture of plasters

Country Status (1)

Country Link
US (1) US1986001A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3189511A (en) * 1962-11-23 1965-06-15 Nat Gypsum Co Gypsum wallboard
FR2578831A1 (en) * 1985-03-15 1986-09-19 Weber Sa A PROCESS FOR RAPID CURING OF NATURAL ANHYDRITE

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3189511A (en) * 1962-11-23 1965-06-15 Nat Gypsum Co Gypsum wallboard
FR2578831A1 (en) * 1985-03-15 1986-09-19 Weber Sa A PROCESS FOR RAPID CURING OF NATURAL ANHYDRITE
EP0198780A1 (en) * 1985-03-15 1986-10-22 A. Weber, S.A. Process for the fast hardening of natural anhydrite

Similar Documents

Publication Publication Date Title
US1965538A (en) Porous magnesia cement
EP3805181B2 (en) Process for applying a fast drying building material composition based on a mineral hybrid adhesive
CN105272097A (en) Novel magnesian cementing material and preparation method for magnesian cementing plate prepared from novel magnesian cementing material
JPS6319462B2 (en)
CA2964226C (en) Compositions with synthetic calcined gypsum coated with diethylene-triamine-pentaacetic acid (dpta) and methods
US1986001A (en) Manufacture of plasters
US2057330A (en) Process of producing artificial stone
RU2453516C1 (en) Self-levelling magnesia composition
US2248033A (en) Manufacture of cements from calcium sulphate and blast furnace slag
US1087098A (en) Porous artificial stone and its production.
US1561473A (en) Composition of matter and method of making the same
US2310023A (en) Set stabilized plaster
US2205734A (en) Composition of matter
DE102021125435A1 (en) Process for providing a gypsum-based building material
US2013811A (en) Hydrated lime composition
US1529228A (en) Cement composition
US3054687A (en) Retardation of set time of aqueous gypsum compositions
US1703125A (en) Plaster
US1102358A (en) Process of making magnesium cement.
US1251841A (en) Plaster or cement composition and method of making the same.
DE2150395C2 (en) Foaming agent for cementitious compounds
US745476A (en) Steam-indurated stone.
US2103216A (en) Calcium sulphate plasters
US1838147A (en) Plastic magnesia mixture
US843277A (en) Method of treating lime.