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JP-7857420-B2 - Alumina cement and calcium silicate-based two-component mortar system and its use

JP7857420B2JP 7857420 B2JP7857420 B2JP 7857420B2JP-7857420-B2

Inventors

  • マーク ホイッテカー
  • マークス シェーンライン

Assignees

  • ヒルティ アクチエンゲゼルシャフト

Dates

Publication Date
20260512
Application Date
20230228
Priority Date
20220308

Claims (13)

  1. A two-component mortar system comprising curing-type aqueous phase alumina cement component A and an initiator component B in the aqueous phase for initiating the curing process, wherein component A further comprises a blocking agent and water, and component B comprises blocked calcium silicate cement and water. The blocked calcium silicate cement contains calcium silicate cement, and the calcium silicate cement does not contain an aluminate clinker phase and does not contain lime. The blocking agent is sodium gluconate, and the mortar is a two-component system.
  2. The two-component mortar system according to claim 1 , wherein the calcium silicate cement is present in an amount ranging from 10 % to 80% by weight based on the total weight of component B.
  3. The two-component mortar system according to claim 1 or 2 , wherein the blocking agent for the calcium silicate cement is present in an amount ranging from 0.01 % by weight to 10 % by weight based on the total weight of component B.
  4. The two-component mortar system according to claim 1 , wherein the calcium silicate cement is tricalcium silicate C3S , dicalcium silicate C2S , or a mixture thereof, which are siliceous clinker phases.
  5. The two-component mortar system according to claim 1 , wherein the calcium silicate cement is tricalcium silicate C3S that does not contain an aluminate clinker phase and does not contain lime.
  6. The two-component mortar system according to claim 1, wherein the shelf life of components A and B is at least six months.
  7. The two-component mortar system according to claim 1, wherein components A and B are in the form of a slurry or paste.
  8. The two-component mortar system according to claim 1, wherein the pH value of component B exceeds 11.
  9. Component B is, A C3S mixture containing 45% to 85% by weight, which does not contain an aluminate clinker phase and does not contain lime, 0.01 to 0.5% by weight of sodium gluconate, A two-component mortar system according to claim 1, comprising 10% to 35% by weight of water.
  10. Use of the two-component mortar system according to claim 1 for chemically fixing an adhesive means in a mineral substrate.
  11. The use according to claim 10 , wherein the fastening means is a metal element .
  12. The use according to claim 10 or 11 , wherein the mineral substrate is a structure made of brickwork, concrete, permeable concrete, or natural stone.
  13. A method for chemically fixing an adhesive means in a mineral substrate, characterized in that a two-component mortar system is used, comprising a curing-type aqueous phase alumina cement component A and an initiator component B in the aqueous phase for initiating the curing process, wherein component A further comprises a blocking agent and water, and component B comprises blocked calcium silicate cement and water. The blocked calcium silicate cement contains calcium silicate cement, and the calcium silicate cement does not contain an aluminate clinker phase and does not contain lime. The blocking agent is sodium gluconate. The method described above is - The process of introducing boreholes into a mineral substrate, - A step of mixing component A and component B to obtain a hardening alumina cement composition, - A step of directly inserting this hardening alumina cement composition into the borehole, - The process of inserting and adjusting fixed building elements, A method comprising the step of hardening and setting the alumina cement composition.

Description

The present invention relates to a two-component mortar system for the chemical fixation of fasteners in mineral substrates, comprising a curing aqueous phase alumina cement component A and an initiator component B in the aqueous phase for initiating the curing process, wherein component A further comprises at least one blocking agent selected from the group consisting of boric acid, phosphoric acid, metaphosphoric acid, phosphorous acid, and phosphonic acid, and water, and component B comprises blocked calcium silicate cement and water. Furthermore, the present invention relates to a ready-to-use two-component mortar system for the chemical fixation of fasteners, preferably metallic elements, in mineral substrates such as brickwork, concrete, permeable concrete, or structures made of natural stone, and its use for the chemical fixation of fasteners. Many two-component mortar systems exist, sometimes referred to as kits of parts. Each component is mixed before use or during application to initiate the curing process, intended to provide good chemical fixation of the adhesive in a mineral substrate. For example, when rapid hardening is desired, organic systems based on free-radical polymerizable resins are used. However, such systems are generally known to be polluting, expensive, and potentially hazardous and/or toxic to the environment and those handling them; they often require special labeling. Furthermore, organic systems often exhibit a significant decrease in stability when thermally exposed to strong sunlight or, otherwise, high temperatures, thereby reducing their mechanical performance in terms of chemical fixation of the adhesive. To overcome these drawbacks, systems based primarily on alumina cement, mainly minerals, have been developed. Alumina cement, with monocalcium aluminate as its main component, is widely used in the building and construction industries because the final product exhibits high levels of mechanical performance over long periods. Furthermore, alumina cement is resistant to bases, achieves maximum strength more quickly than Portland cement, and can withstand sulfate solutions. Therefore, alumina cement systems are preferred for use in chemical fixation applications. Furthermore, calcium aluminate slurry is known to provide high fire resistance to fixing points. However, compared to resin-based fixing mortars, the curing of such systems is considerably slower, which often requires longer waiting times on site and disrupts the workflow. This is particularly important for fixing applications where immediate loading is crucial. In addition, calcium aluminate mortars undergo conversion, resulting in a decrease in performance over time, due to the transformation of the metastable hydrate phases CAH10 and C2AH8 to the stable hydrate C3AH6 . This is particularly pronounced in warm, humid environments, where the established metastable cement hydrates convert to a denser state, increasing porosity and ultimately degrading performance. Blends of powdered ordinary Portland cement with calcium aluminate cement or calcium sulfoaluminate cement are known for the development of fast repair mortars. Because calcium aluminate cement is far more reactive than ordinary Portland cement, adding it in small amounts—approximately 10% of the total cement content—allows for shorter curing times and higher young-age strength, e.g., less than one day. However, commercially available fast repair products, such as Quickrete® Fastset repair mortar, required on-site preparation by mixing powdered cement with a liquid phase. European Patent No. 2162410 describes a ready-to-use two-component system comprising part A, based on aqueous alumina cement delayed with boric acid or a salt thereof, and part B, for initiating a curing process. The initiator in part B is made solely of a lithium salt. European Patent No. 0081385 also discloses a two-component system comprising an aqueous high-alumina cement composition with inhibited setting and a reactivator composition containing a lithium salt. European Patent No. 2794510 describes a stabilized aqueous suspension comprising alumina cement and/or calcium sulfoaluminate cement, which is inhibited by a phosphorus-containing compound and can be stored for a sufficient period of time even at high temperatures. This stabilized aqueous suspension may serve as a base for surface coatings. However, these alumina-cement aqueous suspensions, delayed by boric acid or its salts, are often not very stable for sufficient storage time before use. Furthermore, boric acid is highly toxic and ecotoxic. Moreover, these modern systems require a high water-to-cement ratio and are characterized by their undesirable conversion, which degrades performance over time. German Patent No. 2311239 describes an auxiliary composition for improving the setting and hardening properties of alumina cement and mortar, comprising lithium, a water-soluble lithium salt, and a hydroxylated organic acid or it