Verfahren zur Herstellung von einem Klebemittel

An adhesive composition for bonding building materials is prepared by mixing a sand-lime mixture (as is used for making sand-lime bricks) with aqueous formaldehyde in such proportions that a dry homogeneous product is obtained and mixing the resulting product with a phenol-formaldehyde resin. The sand-lime-formaldehyde product may be allowed to set for 24 hours before it is mixed with the resin and an alkaline catalyst, e.g. monoethanolamine or Portland cement, may be included in the final mixture. The sand-lime-formaldehyde product is said to be storable in air-tight containers for up to a year. In Example 1, 9 parts sand-lime mixture is mixed with 1 part of 37% aqueous formaldehyde and after 24 hours 2 parts of the product is mixed with 1 part of resin. Example 2 is similar, except that 2 to 6% monoethanolamine is included with the resin. In Example 3, 6 parts of sand-lime mixture are mixed with 1 part 37% formaldehyde and the product is mixed with 3 to 4 1/2 parts Portland cement to give a second product, 2 parts of which are mixed with 1 of resin.ALSO:An adhesive composition for bonding building materials is prepared by (i) mixing a sand-lime mixture (as is used for making sand-lime bricks) with aqueous formaldehyde in such proportions that a dry homogeneous product is obtained and (ii) mixing the resulting product with a phenol-formaldehyde resin. The product of step (i) may be allowed to set for 24 hours before step (ii) and is said to be storable for up to a year in air-tight containers. An alkaline catalyst, e.g. ethanolamine or Portland cement may be included.