Resin composition and process for bond solid particles

Claim 2

IN A PROCESS FOR BONDING DISCRETE SOLID PARTICLES WHICH COMPRISES ADMIXING SAID PARTICLES WITH AN AQUEOUS RESIN BINDER COMPOSITION AND A CURING ACCELERATOR SELECTED FROM THE GROUP CONSISTING OF ACIDS AND SALTS TO YIELD A WET MIXTURE, AND HEATING THE RESULTING WET MIXTURE TO EFFECT SETTING OF THE RESINOUS COMPONENTS; THE IMPROVEMENT COMPRISING EMPLOYING A RESINOUS BINDER COMPOSITION PREPARED BY REACTING A UREA COMPOSITION SELECTED FROM THE GROUP CONSISTING OF A UREAFORMALDEHYDE AND A THIOUREA-FORMALDEHYDE HAVING A MOLAR RATIO OF UREA AND/OR THOOUREA TO FORMALDEHYDE IN THE RANGE OF ABOUT 1:2 TO ABOUT 1:5 AND WHICH HAS BEEN HEATED AT A TEMPERATURE IN THE RANGE OF ABOUT 50 TO 100 DEGREES CENTIGRADE AT A PH OF ABOUT 5 TO 6, WITH A PHENOL AND FORMALDEHYDE IN THE PRESENCE OF AN ALKALINE CATALYST AT A TEMPERATURE OF AT LEAST ABOUT 100 DEGREES CENTIGRADE, SAID PHENOL AND ADDED FORMALDEHYDE EMPLOYED IN A MOLAR RATIO IN THE RANGE OF ABOUT 0.25:1 TO 1:1 TO PRODUCE A RESIN BINDER COMPOSITION HAVING A TOTAL MOLAR RATIO OF UREA AND/OR THIOUREA TO FORMALDEHYDE OF ABOUT 1:4 TO ABOUT 1:8, AND A WATER TOLERANCE OF AT LEAST 50 PERCENT.

Claim 3

The process of claim 1 wherein the discrete solid particles are sand.

Claim 4

The process of claim 1 wherein the discrete solid particles are wood.

Claim 5

The process of claim 1 wherein the discrete solid particles are a refractory material.

Claim 6

The process of claim 2 wherein the wet mixture is introduced to a hot core box to form a core of a desired shape, whereby the wet mixture is heated to effect setting of the resinous components.

Claim 7

The process of claim 5 wherein the curing accelerator is ammonium chloride.

Claim 8

The process of claim 5 wherein the curing accelerator is an aqueous solution of ammonium nitrate.

Claim 9

The process of claim 2 wherein the wet mixture is introduced to a core box which is at a temperature in the range of about 75* to about 300* F, and heated gas is passed through the wet mixture, to effect setting of the resinous components.

Claim 10

The process of claim 8 wherein the curing accelerator is ammonium chloride.

Claim 11

The process of claim 3 wherein the wet mixture is pressed into a form of the desired shape, and the shaped wet mixture is heated to effect setting of the resinous components.

Claim 12

The process of claim 4 wherein the wet mixture is pressed into a form of the desired shape, and the shaped wet mixture is heated to effect setting of the resinous components.

Claim 13

A composition comprising discrete solid particles, and a resinous binder composition prepared by reacting a urea composition selected from the group consisting of a urea-formaldehyde and a thiourea-formaldehyde having a molar ratio of urea and/or thiourea to formaldehyde in the range of about 1:2 to about 1:5 and which has been heated at a temperature in the range of about 50 to 100 degrees centigrade at a pH of about 5 to 6, with a phenol and formaldehyde in the presence of an alkaline catalyst at a temperature of at least about 100 degrees centigrade, said phenol and added formaldehyde employed in a molar ratio in the range of about 0.25:1 to 1:1 to produce a resin binder composition having a molar ratio of urea and/or thiourea to formaldehyde of about 1:4 to about 1:8, and a water tolerance of at least 50 percent.

Claim 14

A composition comprising discrete solid particles, and a resinous binder composition prepared by reacting a urea composition selected from the group consisting of a urea-formaldehyde and a thiourea-formaldehyde having a molar ratio of urea and/or thiourea to formaldehyde in the range of about 1:2 to about 1:5 and which has been heated at a temperature in the range of about 50 to 100 degrees centigrade at a pH of about 5 to 6, with a phenol and formaldehyde in the presence of an alkaline catalyst at a temperature of at least about 100 degrees centigrade, said phenol and added formaldehyde employed in a molar ratio in the range of about 0.25:1 to 1:1 to produce a resin binder composition having a molar ratio of urea and/or thiourea to formaldehyde of about 1:4 to about 1:8, and a water tolerance of at least 50 percent.

Claim 15

The composition of claim 12 wherein the discrete solid particlEs are sand and the resin binder composition is present in a proportion of about 0.2 to 5 weight percent based on the weight of the sand.

Claim 16

The composition of claim 12 wherein the discrete solid particles are wood and the resin binder composition is present in a proportion of about 2 to about 25 weight percent based on the weight of the wood particles.

Claim 17

The molded composition of claim 12 wherein the discrete solid particles are refractory particles and the resin binder composition is present in proportion of about 2 to 25 weight percent based on the weight of the refractory particles.

Claim 18

In a process for bonding discrete solid particles which comprises admixing said particles with an aqueous resin binder composition and a curing accelerator selected from the group consisting of acids and salts to yield a wet mixture, and heating the resulting wet mixture to effect setting of the resinous components; the improvement comprising employing a resinous binder composition prepared by reacting a urea composition selected from the group consisting of a urea-formaldehyde and a thiourea-formaldehyde having a molar ratio of urea and/or thiourea to formaldehyde in the range of about 1:2 to about 1:5 and which has been heated at a temperature in the range of about 50* to 100* C at a pH of about 5 to 6, with a phenol, formaldehyde and a urea compound selected from the group consisting of urea and thiourea, in the presence of an alkaline catalyst at a temperature of at least about 100* C, said urea or thiourea employed in a proportion to provide a molar ratio of urea and/or thiourea to formaldehyde of about 1:4 to 1:8 in the resin binder composition; and said phenol employed in a proportion to provide a total molar proportion of phenol or urea and/or thiourea in the range of about 1:0.5 to about 1:1.5 in the resin binder composition, which has a water tolerance of at least 50 per cent.

Claim 19

In a process for bonding discrete solid particles which comprises admixing said particles with an aqueous resin binder composition and a curing accelerator selected from the group consisting of acids and salts to yield a wet mixture, and heating the resulting wet mixture to effect setting of the resinous components; the improvement comprising employing a resinous binder composition prepared by reacting a urea composition selected from the group consisting of a urea-formaldehyde and a thiourea-formaldehyde having a molar ratio of urea and/or thiourea to formaldehyde in the range of about 1:2 to about 1:5 and which has been heated at a temperature in the range of about 50* to 100* C at a pH of about 5 to 6, with a phenol, formaldehyde and a urea compound selected from the group consisting of urea and thiourea, in the presence of an alkaline catalyst at a temperature of at least about 100* C, said urea or thiourea employed in a proportion to provide a molar ratio of urea and/or thiourea to formaldehyde of about 1:4 to 1:8 in the resin binder composition; and said phenol employed in a proportion to provide a total molar proportion of phenol or urea and/or thiourea in the range of about 1:0.5 to about 1:1.5 in the resin binder composition, which has a water tolerance of at least 50 per cent.

Claim 20

The process of claim 16 wherein the discrete solid particles are sand.

Claim 21

The process of claim 17 wherein the wet mixture is introduced to a hot core box to form a core of a desired shape, whereby the wet mixture is heated to effect setting of the resinous components.

Claim 22

The process of claim 18 wherein the curing accelerator is ammonium chloride.

Claim 23

The process of claim 20 wherein the curing accelerator is an aqueous solution of ammonium nitrate.

Claim 24

A composition comprising discrete solid particles, and a resinous binder composition prepared by reacting a urea composition selected from the group consisting of a urea-formaldehyde and a thiourea-formaldehyde in the range of about 1: 2 to about 1:5 and which has been heated at a temperature in the range of about 50* to 100* C at a pH of about 5 to 6, with a phenol, formaldehyde and a urea compound selected from the group consisting of urea and thiourea, in the presence of an alkaline catalyst at a temperature of at least about 100* C, said urea or thiourea employed in a proportion to provide a molar ratio of urea and/or thiourea to formaldehyde of about 1:4 to about 1:8 in the resin binder composition; and said phenol employed in a proportion to provide a total molar ratio of phenol to urea and/or thiourea in the range of about 1:0.5 to about 1:1.5 in the resin binder composition, which has a water tolerance of at least 50 percent.

Claim 25

A composition comprising discrete solid particles, and a resinous binder composition prepared by reacting a urea composition selected from the group consisting of a urea-formaldehyde and a thiourea-formaldehyde in the range of about 1: 2 to about 1:5 and which has been heated at a temperature in the range of about 50* to 100* C at a pH of about 5 to 6, with a phenol, formaldehyde and a urea compound selected from the group consisting of urea and thiourea, in the presence of an alkaline catalyst at a temperature of at least about 100* C, said urea or thiourea employed in a proportion to provide a molar ratio of urea and/or thiourea to formaldehyde of about 1:4 to about 1:8 in the resin binder composition; and said phenol employed in a proportion to provide a total molar ratio of phenol to urea and/or thiourea in the range of about 1:0.5 to about 1:1.5 in the resin binder composition, which has a water tolerance of at least 50 percent.

Claim 26

The composition of claim 21 wherein the discrete solid particles are sand and the resin binder composition is present in a proportion of about 0.2 to 5 weight percent based on the weight of the sand.