摘要:
A set accelerator for at least one of accelerating the hydration rate and reducing the set time of an aqueous slurry of calcium sulfate hemihydrate is described. The set accelerator consists of a mixture of ground calcium sulfate dihydrate and zinc sulfate material. Aluminum sulfate material is an optional component of the set accelerator. The set accelerator is particularly useful in accelerating the hydration rates of sprayable plasters. A fluid form of the set accelerator may be made by suspending the solids in water. The fluid form is advantageously used in ready mixed setting type joint compounds.
摘要:
At least one of these or other problems is reduced using a building material that is uniquely identifiable. A method of making an identifiable gypsum-based building product includes selecting a tagging material occurring naturally in a component of the building material and choosing a carrier substance having a high concentration of the tagging material. By selecting an amount of the carrier substance and adding it to the building material, a building product having a unique product characteristic is created. In a second embodiment of the invention, a second tagging material is combined with the first tagging material to create a unique product. In yet another embodiment of the invention, a supplemental amount of the tagging material is added to the gypsum-based composition in addition to the carrier substance. Some tagging materials are useful in a gypsum-based composition to produce a visual confirmation of the presence of the tagging material.
摘要:
The invention is directed to a joint tape for finishing a joint between boards comprising a nonwoven substrate that does not swell substantially in the presence of water. The invention further provides a method of finishing a joint between boards comprising (i) applying a joint tape of the invention to a joint between boards by embedding the joint tape in a first coat of joint compound, (ii) applying a second coat of joint compound over the tape, wherein step (ii) is carried out before the joint tape and joint compound applied in step (i) have substantially dried, and optionally (iii) applying a third fill or finish coat of joint compound over the tape, wherein step (iii) is carried out before the joint tape and second coat have substantially dried.
摘要:
The invention is directed to a joint tape for finishing a joint between boards comprising a nonwoven substrate that does not swell substantially in the presence of water. The invention further provides a method of finishing a joint between boards comprising (i) applying a joint tape of the invention to a joint between boards by embedding the joint tape in a first coat of joint compound, (ii) applying a second coat of joint compound over the tape, wherein step (ii) is carried out before the joint tape and joint compound applied in step (i) have substantially dried, and optionally (iii) applying a third fill or finish coat of joint compound over the tape, wherein step (iii) is carried out before the joint tape and second coat have substantially dried.
摘要:
At least one of these or other problems is reduced using a building material that is uniquely identifiable. A method of making an identifiable gypsum-based building product includes selecting a tagging material occurring naturally in a component of the building material and choosing a carrier substance having a high concentration of the tagging material. By selecting an amount of the carrier substance and adding it to the building material, a building product having a unique product characteristic is created. In a second embodiment of the invention, a second tagging material is combined with the first tagging material to create a unique product. In yet another embodiment of the invention, a supplemental amount of the tagging material is added to the gypsum-based composition in addition to the carrier substance. Some tagging materials are useful in a gypsum-based composition to produce a visual confirmation of the presence of the tagging material.
摘要:
The joint compound of the present invention utilizes hollow resin microspheres with a mean particle size less than 75 microns and exhibiting no more than 1.5% increase in density under high shear stress testing.
摘要:
A joint compound system includes a set-inhibited, pre-wetted, setting-type, ready-mix joint compound and a set initiator. The set-inhibited, pre-wetted, setting-type joint compound includes a ready-mixed, setting-type joint compound base with a calcium-free phosphate set preventing agent that impedes chemical hydration of a gypsum component of the setting-type joint compound. The joint compound base is free of calcium carbonate. The set initiator includes alum to reinitiate the chemical hydration reactions.
摘要:
A rough-surfaced substrate, such as a fiberboard, is provided with a smoother surface by applying a coating comprising calcium sulfate hemihydrate which has been prevented from hydrating to gypsum by set preventer, and which sets when brought into contact with a set initiator, e.g. aluminum sulfate, preferably present on the surface of the substrate.
摘要:
A two part joint compound which sets by hydration of calcium sulfate hemihydrate to gypsum and is clay-free. One part includes an in-situ acidic acrylate copolymer thickener (i.e., an associative thickener) with the calcium sulfate hemihydrate, along with a non-calcium bearing phosphate set preventer. The first part contains water, but remains unset for at least 175 days. The second part includes a set initiator compound having a cation with a log K value greater than calcium ions. The second part is mixed with the first part when setting is desired.
摘要:
A cementitious composition of the setting type which can be kept in a ready-mixed state and which can be caused to set and harden upon introduction of an accelerator with reproducibility and set time predictability. The cementitious base composition contains calcium sulfate hemihydrate as a principal filler material and certain non-calcium bearing phosphate additives which prevent setting action in the presence of water. An accelerator, such as zinc sulfate, may be added to the ready-mixed, cementitious composition to initiate the setting action, or the ready-mixed cementitious composition can be used as a drying type joint compound without the addition of an accelerator.