JP2006509119A - Filler-fiber composite - Google Patents

Abstract

The present invention relates to filler-fiber composites, methods for their production, their use in the production of paper or paperboard products, and paper made therefrom. More particularly, the present invention relates to a filler-fiber composite in which the morphology and particle size of the inorganic filler is established before the bond to the fiber occurs. Even more particularly, the present invention relates to PCC filler-fiber composites that achieve the desired optical properties and physical properties of the paper produced therefrom.

Description

  The present invention relates to a filler-fiber composite, a process for its production, its use in the production of paper or paperboard products, and paper produced therefrom. More particularly, the present invention relates to a filler-fiber composite in which the morphology and particle size of the inorganic filler is established before the bond to the fiber occurs. Even more particularly, the present invention relates to PCC filler-fiber composites that achieve the desired optical properties and physical properties of the paper produced therefrom.

  Providing particulate fillers such as calcium carbonate, talc and clay on the fibers for subsequent paper and paper product manufacture continues to be a challenge. Many methods with some success have been used to address this problem. To ensure that the filler remains with or in the fiber web, retention aids are used, direct precipitation onto the fiber is used, and the filler is bonded directly to the fiber surface. Used to mix fibers and fillers, uses precipitation in never dried pulp, uses a method of filling cellulose fibers, uses high shear mixing, Pulp fiber in which fibrous material and calcium carbonate are reacted with carbon dioxide in a closed pressure vessel, the filler is captured by mechanical bonds, a cationically charged polymer is used, and calcium carbonate is filled All lumens were used to retain the filler in the fibers for subsequent use in the paper. Most methods for fiber retention are expensive and inefficient.

  Therefore, what is needed is a filler fiber composite and method for making the same that is both effective to hold the filler and inexpensive to use by the paper manufacturer. .

  The object of the present invention is therefore to produce a filler-fiber composite. Another object of the present invention is to provide a method for producing a filler-fiber composite. On the other hand, another object of the present invention is to produce a filler-fiber composite that maintains physical properties such as tensile strength, fracture length and internal bond strength. A still further object of the present invention is to produce a filler-fiber composite that maintains optical properties such as ISO opacity and pigment scattering. On the other hand, a still further object of the present invention is to provide filler-fiber composites that are particularly useful in paper and paperboard products.

Related Art U.S. Pat. No. 6,156,118 teaches mixing calcium carbonate filler and short sized short fiber of P50 or less.
U.S. Pat. No. 5,096,539 teaches that an inorganic filler is precipitated in situ with pulp that never dries.
U.S. Pat. No. 5,223,090 teaches a method of filling cellulose fibers using high shear mixing of crumb pulp during the carbon dioxide reaction.
US Pat. No. 5,665,205 combines fiber pulp slurry and alkali salt slurry in the contact zone of the reactor so that the slurry is immediately contacted with oxygen dioxide so that the fibers settle on the secondary pulp fibers. Teaches how to mix.
U.S. Pat. No. 5,679,220 describes the incorporation of fillers in papermaking fibers in a stream where shear is applied to the gas phase to immediately complete the conversion of calcium hydroxide to calcium carbonate. Teaches a continuous method for stew deposition.
US Pat. No. 5,122,230 teaches a method for modifying hydrophilic fibers using substantially water-insoluble inorganic material in situ precipitation.
US Pat. No. 5,733,461 teaches a method for the recovery and use of fines present in the wastewater stream produced in the paper manufacturing process.
U.S. Pat. No. 5,731,080 discloses an insufficiency in which the majority of calcium carbonate captures microfibers by a reliable and unreliable mechanical bond without a binder or retention aid. Teaches stew precipitation.
US Pat. No. 5,928,470 teaches a method for producing metal oxide or metal hydroxide-modified cellulose pulp.
U.S. Pat. No. 6,235,150 teaches a method for producing a pulp fiber lumen filled with calcium carbonate having a particle size of 0.4 to 1.5 microns.

  The problem of ensuring that filler materials such as calcium carbonate, ground calcium carbonate, clay and talc stay in the fibers to be finally used in paper has been subjected to numerous proofs. However, none of the prior art discloses a filler fiber composite in which the morphology of the filler is predetermined prior to the introduction of the fiber, its method of manufacture or its use in paper or paper products.

  The present invention provides a first partial reactor by supplying a slake containing seeds to the first stage reactor, and reacting the slake containing the seeds in the presence of carbon dioxide in the first stage reactor. Producing a converted calcium hydroxide calcium carbonate slurry; reacting the first partially converted calcium hydroxide calcium carbonate slurry in the second stage reactor in the presence of carbon dioxide to produce a second partial Producing a calcium hydroxide slurry converted to calcium hydroxide, and reacting the second partially converted calcium hydroxide calcium carbonate slurry in the third stage reactor in the presence of carbon dioxide and fibers to charge The present invention relates to a filler-fiber composite comprising producing a material-fiber composite.

  In another aspect, the invention provides feeding a first-stage reactor with a seed-containing lake in the first-stage reactor in the presence of carbon dioxide in the first-stage reactor. Producing a partially converted calcium hydroxide slurry, and reacting the first partially converted calcium carbonate slurry in the second stage reactor in the presence of carbon dioxide and fibers to produce a filler- The present invention relates to a filler-fiber composite comprising producing a fiber composite.

  In a further aspect, the present invention provides feeding a first stage reactor with a slake containing citric acid, reacting the slake containing citric acid in the first stage reactor in the presence of carbon dioxide, Producing a partially converted calcium hydroxide calcium carbonate slurry, reacting the first partially converted calcium hydroxide calcium carbonate slurry in the second stage reactor in the presence of carbon dioxide; Of a partially converted calcium hydroxide calcium carbonate slurry and reacting a second partially converted calcium hydroxide calcium carbonate slurry in the presence of carbon dioxide and fibers in a third stage reactor. And a filler-fiber composite comprising producing a filler-fiber composite.

In yet a further aspect, the present invention provides feeding a slake containing citric acid to a first stage reactor, reacting the slake containing citric acid in the first stage reactor in the presence of carbon dioxide, To produce one partially converted calcium hydroxide calcium carbonate slurry, take the first portion of the partially converted calcium hydroxide calcium carbonate slurry, add the fiber, and add it to the second stage reactor Reacting in the presence of carbon dioxide to produce a calcium carbonate / fiber composite to act as a heel, taking a second portion of the partially converted calcium hydroxide calcium carbonate slurry; adding fibers and surfactant, are reacted in the presence of CO _2, the second partially converted _Ca (OH) 2 / CaCO ₃ Causing the fiber material, and is reacted in a second partially converted _{Ca (OH) 2 / CaCO 3} / third stage reactor fibrous material in the presence of CO _2, filler - fiber composite The filler-fiber composite.

In yet a further aspect, the present invention provides feeding a slake containing citric acid to a first stage reactor, reacting the slake containing citric acid in the first stage reactor in the presence of carbon dioxide, To produce one partially converted calcium hydroxide calcium carbonate slurry, take the first portion of the partially converted calcium hydroxide calcium carbonate slurry, add the fiber, and add it to the second stage reactor Reacting in the presence of carbon dioxide to produce a calcium carbonate / fiber composite to act as a heel, taking a second portion of the partially converted calcium hydroxide calcium carbonate slurry; adding fibers and polyacrylamide are reacted in the presence of CO _2, the second partially converted Ca _(OH) 2 / Ca O ₃ / causing the fibrous material, and is reacted in a second partially converted _Ca (OH) 2 / CaCO ₃ / third stage reactor fibrous material in the presence of CO _2, the filler / The present invention relates to a filler-fiber composite comprising producing a fiber composite.

In a last aspect, the present invention provides feeding a slake containing citric acid to a first stage reactor, reacting the slake containing citric acid in the presence of carbon dioxide in the first stage reactor, Producing a ₃ heel, adding a sodium carbonate containing slake to the heel material of the first stage reactor in the presence of CO ₂ to produce a partially converted calcium hydroxide calcium carbonate slurry; The present invention relates to a filler-fiber composite comprising reacting a calcium hydroxide calcium carbonate slurry converted to a second stage reactor in the presence of carbon dioxide and fibers to form a filler-fiber composite.

The fibers used in the present invention are defined as fibers produced by refining cellulose (any pulp refiner known in the pulp processing industry) and / or mechanical pulp fibers. The fibers are typically 0.1-2 microns in thickness and 10-400 microns in length and are additionally manufactured according to US Pat. No. 6,251,222, which publication is incorporated herein by this reference. It is.

Precipitation continuous flow stirred tank reactor (CFSTR) of PCC with different morphologies

Declinated Trihedral Morphology The first step in this method involves making a highly reactive Ca (OH) ₂ lime milk slake and sieving it with -325 mesh. This slake is then added to the stirred reactor, it is the desired reaction temperature, 0.1 percent citric acid is added to the slake prevents aragonite formation, and reacted with CO ₂ gas. The reaction proceeds from 10% to 40% of the total process, at which point the reaction is stopped. This yields a partially converted Ca (OH) ₂ / CaCO ₃ slurry (about 20 wt% solids), which in turn provides a CO ₂ gas supply that maintains a given conductivity (ionic saturation). Is supplied to the reaction vessel at a speed suitable for the above, to produce a decentered trihedral crystal. This reaction proceeds until process stabilization is achieved. The product produced when stabilization is achieved (about 95% conversion) is then mixed with diluted fiber (about 1.5% concentration) and water. This mixture is then reacted with CO ₂ gas until an endpoint pH of 7.0. The product produced using this method can contain from about 0.2 to about 99.8% declinated trihedral PCC with respect to fiber at 3 to 5% total solids.

  The product has a specific surface area of about 5 to about 11 square meters / gram; a product solids content of about 3 to about 5% and a PCC content of about 0.2 to about 99.8%, with a majority Trihedral morphology.

Aragonitic Morphology The first step in this process involves making a highly reactive Ca (OH) ₂ lime milk slake and sieving with -325 mesh. The concentration of this slake is about 15% by weight. This lake is then added to the stirred reactor, brought to the desired reaction temperature, about 0.05 to about 0.04% additive is added to indicate morphology and size, and CO ₂ gas Is reacted with. The reaction proceeds 10-40% of all steps, at which point the reaction is stopped. This results in a partially converted Ca (OH) ₂ / CaCO ₃ slurry, which in turn enters the reaction vessel at a rate suitable for the CO ₂ gas supply that maintains a given conductivity (ionic saturation). Supplied to produce acicular aragonite crystals. This reaction continues until process stabilization is achieved. The product produced (about 95% calcium carbonate) once stabilization is achieved is mixed with diluted fiber (about 1.5% concentration) and water. Calcium carbonate and fibers are then reacted with CO ₂ gas to the end point pH 7.0. The product produced using this method contains about 0.2 to about 99.8% aragonite PCC with respect to the fiber at about 3 to about 5% total solids.

  The product has a specific surface area of about 5 to about 8 square meters / gram; a product solids content of about 3 to about 5% by weight and a PCC content of about 0.2 to about 99.8% with respect to the fiber, Has a partial aragonite morphology.

The rhombohedral morphology The first step in this process involves making a highly reactive Ca (OH) ₂ lime milk slake, which is sieved through -325 mesh and has a concentration of about 20% by weight. 0.1% citric acid is added to prevent aragonite formation. A portion of this lake is added to the stirred reactor, brought to the desired reaction temperature and saturated with CO ₂ gas. The reaction proceeds to minimum conductivity, resulting in a “heel”. "Heal" is defined as fully converted calcium carbonate crystals having an arbitrary particle morphology, typically having an average particle size in the range of about 1 to about 2.5 microns. Sodium carbonate is added to the remainder of the slake that is not used to make the “heel” material. This slake and CO ₂ is added to the “heel” material at a CO ₂ feed rate that maintains a given conductivity (ionic saturation) to produce rhombohedral crystals. The reaction is continued until process stabilization is achieved. Once stabilization is achieved, this product (about 90-95% conversion) is mixed with diluted fiber “(about 1.5% concentration) and water. Additional CO ₂ is added to the end point at pH 7.0. The product produced using this method contains about 0.2 to about 99.8% rhombohedral PCC with respect to the fiber, and has a total solids content of about 3 to about 5%.

  The product has a specific surface area of about 5 to about 8 square meters per gram; a product solids content of about 3 to about 5% and a PCC content of about 0.2 to about 99.8%, mostly diagonally Has a hexahedral morphology.

  The following examples are intended to illustrate the invention and are not intended to limit the scope of the invention.

Example 1
Eccentric trihedral PCC
15 liters of water and 3 kilograms of CaO were reacted at 50 ° C. to produce a 20 wt% Ca (OH) ₂ lake. The Ca (OH) ₂ slake is then screened with -325 mesh, resulting in a sieved slake which is duplicated in the first 30 liters with agitation of 615 revolutions per minute (rpm). It was transferred to a jacketed stainless steel reactor. 0.1% by weight citric acid of the total theoretical CaCO ₃ to be produced was added to the screened slake in the 30 liter reactor and the temperature of the contents was brought to 40 ° C. Begin the addition of 20% CO ₂ gas in air (14.83 standard liters CO ₂ /59.30 standard liters air) to a 30 liter reactor, 2: 1 Ca (OH) ₂ / CaCO _Three slurries were produced. At this point, the CO ₂ gas supply was stopped and the slurry was transferred to a stirred 20 liter storage vessel.

2 liters of 2: 1 Ca (OH) ₂ / CaCO ₃ slurry was transferred to the first 4 liters of stirred (1250 rpm) stainless steel double jacketed reactor. The temperature is 51 ° C. and 20% CO ₂ gas in air (1.41 standard liters CO ₂ /5.64 standard liters air) is added to the first 4 liter reactor until pH 7.0 is achieved. And a CaCO ₃ slurry was produced. Once pH 7.0 is achieved, 20% CO ₂ gas in air (1.41 standard liters CO ₂ /5.64 standard liters of air) continues to be added to the first 4 liter reactor with approximately 90% ions. While maintaining saturation conductivity, the addition of a 2: 1 Ca (OH) ₂ / CaCO ₃ slurry in a 20 liter storage vessel to the first 4 liter reactor was begun. The addition of Ca (OH) ₂ / CaCO ₃ slurry and CO ₂ to the first 4 liter reactor was continued for about 12 hours until the physical properties of the product remained essentially unchanged, with about 98% conversion. A CaCO ₃ slurry was produced. 0.18 liter of 98% CaCO ₃ slurry was transferred to a second 4 liter stirred (1250 rpm) stainless steel double jacketed reactor and 0.66 liter 3.8% dry weight by weight Of cellulose fiber was added and diluted to 1.5% consistency. This mixture of CaCO ₃ slurry and fiber is reacted with 20% CO _{2 in} air (1.41 standard liters CO ₂ /5.64 standard liters air) to produce a CaCO ₃ filler-fiber composite. did. The calcium carbonate filler mostly had a declinated trihedral morphology.

Example 2
Aragonite PCC
10.5 liters of water and 2.1 kilograms of CaO were reacted at 50 ° C. to produce a 15 wt% Ca (OH) ₂ lake. The Ca (OH) ₂ slake was then screened with -325 mesh, resulting in a sieved slake, which was a 30 liter double jacketed stainless steel reactor with 615 rpm agitation. Moved to. 0.1 wt% high surface area (HSSA) aragonite seed (˜40 square meters per gram surface area, approximately 25% solids) was added to a 30 liter reactor and the temperature of the contents was brought to 51 ° C. The "seed" is fully converted, reacted to the end point and ground to a high specific surface area (ie above 30 square meters per gram, typically 0.1 to 0.4 microns particle size) Defined as aragonite crystals. Start 15 min addition to 30 liter stainless steel double jacketed reactor with 10% CO ₂ gas in air (5.24 standard liter CO ₂ /47.12 standard liter air) The CO ₂ concentration is then increased for an additional 15 minutes to 20% CO ₂ gas in air (10.47 standard liters CO ₂ /41.89 standard liters air) 2.3: 1 Ca An (OH) ₂ / CaCO ₃ slurry was produced. At that time, the CO ₂ gas supply was stopped. The 2.3: 1 Ca (OH) ₂ / CaCO ₃ slurry was transferred to a stirred 20 liter storage vessel. 2 liters of 2.3: 1 Ca (OH) ₂ / CaCO ₃ slurry was transferred to a first 4 liter stirred double jacketed stainless steel reactor set to 1250 rpm stirring. The temperature was 52 ° C. The addition of 20% CO ₂ gas in air (1.00 standard liters CO ₂ /3.99 standard liters air) to the first 4 liter reactor was started, pH 7.0 was achieved and 100% CaCO ₃ The reaction was continued until a slurry was formed. The temperature of the 100% CaCO ₃ slurry in the first 4 liter reactor was 63 ° C. Continue the addition of 20% CO _{2 in} air (1.00 standard liters CO ₂ /3.99 standard liters air) to the first 4 liter reactor to maintain a conductivity of about 90% ionic saturation. However, the addition of 2.3: 1 Ca (OH) ₂ / CaCO ₃ slurry from a 20 liter storage vessel to the first 4 liter reactor was begun. The reaction was continued for about 9 hours until the physical properties of the resulting product remained essentially unchanged, producing a about 98 wt% CaCO ₃ slurry.

0.35 liters of 98% CaCO ₃ slurry was transferred to a second 4 liter stirred (1250 rpm) stainless steel double jacketed reactor and 0.66 liters of 3.8 wt% Cellulose fibers and 1.0 liter of water were added to the second 4 liter reactor to produce a 1.5 wt% CaCO ₃ / fiber mixture. Additional 20% CO _{2 in} air (1.00 standard liters CO ₂ /3.99 standard liters air) is added to the second 4 liter reactor until pH 7.0 is complete. A CaCO ₃ / fiber composite was produced. The composite consisted of about 75% Argonite PCC with respect to the fiber.

Example 3
Rhombohedral PCC
15 liters of water and 3 kilograms of CaO were reacted at 50 ° C. to produce a 20 wt% Ca (OH) ₂ lake. The Ca (OH) ₂ slake was sieved with -325 mesh, resulting in a sieved slake, which was transferred to a stirred 20 liter storage vessel. Two liters of sieved slake from the 20 liter storage vessel was transferred to the first 4 liters of stirred stainless steel double jacketed reactor and agitation was begun at 1250 rpm. 0.03% by weight citric acid of theoretical CaCO ₃ was added to the first 4 liter reactor and the temperature of the contents was raised to 50 ° C. 20% CO ₂ gas in air (1.44 standard liters CO ₂ /5.77 standard liters of air) in the first 4 liters of reaction until pH 7.0 is achieved resulting in a 100% CaCO ₃ slurry. Added to the vessel. To a screened slake in a 20 liter storage vessel, a solution of 1.3 wt% Na ₂ CO ₃ based on the theoretical yield of CaCO ₃ is added and Ca (OH) ₂ / Na ₂ CO _Three slakes were generated. The temperature of the contents of the first 4 liter reactor is raised to about 68 ° C. and the first 4 liters of 20% CO _{2 in} air (1.44 standard liters CO ₂ /5.77 standard liters air). To the first 4 liter reactor of a 20 liter storage vessel Ca (OH) ₂ / Na ₂ CO ₃ slake while maintaining about 50% ionic saturation conductivity. The addition started. The addition of Ca (OH) ₂ / Na ₂ CO ₃ slake and CO ₂ was continued for about 12 hours until the physical properties of the resulting product remained essentially unchanged, resulting in about 98 wt% CaCO ₃ slurry. It was.

0.22 liter of 98 wt% CaCO ₃ slurry was transferred to a second 4 liter stirred (1250 rpm) double jacketed stainless steel reactor and 0.66 liter of 3.8 wt. % Cellulose fiber and 1.0 liter of water were added to the second 4 liter reactor to produce a 1.5 wt% CaCO ₃ / fiber mixture. Additional 20% CO _{2 in} air (1.44 standard liters CO ₂ /5.77 standard liters) until the reaction is complete and pH 7.0 is reached, yielding about 3.4 wt% CaCO ₃ / fiber composite. Was added to the second 4 liter reactor. Calcium carbonate has mostly rhombohedral morphology.

Example 4
Declined trihedron-CFSTR
15 liters of water and 3 kilograms of CaO are reacted at 48 ° C. to produce a Ca (OH) ₂ slake, and 6 liters of water is added to produce a 20 wt% Ca (OH) ₂ slake. did. The 20 wt% Ca (OH) ₂ slake was sieved through -325 mesh and transferred to a 30 liter double jacketed stainless steel reactor with 615 rpm agitation. 0.015 wt% citric acid of the total theoretical CaCO ₃ to be produced was added to the 30 liter reactor and the temperature of the contents was 36 ° C. Begin the addition of 20% CO ₂ gas in air (13.72 standard liters CO ₂ /54.89 standard liters air) to a 30 liter reactor, 5: 1 Ca (OH) ₂ / CaCO _Three slurries were produced. The CO ₂ gas supply was stopped and the _Ca (OH) 2 / CaCO ₃ slurry was transferred to a storage vessel agitated 20-liter.

In a 4 liter stirred storage vessel, combine 0.25 liter Ca (OH) ₂ / CaCO ₃ slurry with 0.66 liter 3.8 wt% fiber and 1.09 liter water to obtain Ca ( was produced _OH) 2 / CaCO ₃ / fiber material. 2 liters of Ca (OH) ₂ / CaCO ₃ / fiber material was transferred to a 4 liter stirred (1250 rev / min) reactor, the temperature was brought to 55 ° C. and 20% CO _{2 in} air (1.30 standard liters) CO ₂ /5.23 standard liters air) was saturated with carbon dioxide to pH 7.0 to produce a CaCO ₃ / fiber composite. 16 liters of 1.5 wt% fiber and a separate 10 liter container of water were prepared. Maintain a conductivity of about 90% ionic saturation in a 4 liter reactor, along with an additional water of 31.21 ml / min, along with a 1.5% consistency fiber mixture at 172.05 ml / min. While maintaining a flow of CO ₂ gas (1.30 standard liters CO ₂ /5.23 standard liters air) at a rate of about 20% while maintaining a mass balance of about 4-5% total solids, Addition of Ca (OH) ₂ / CaCO ₃ slurry in a liter stirred storage vessel was started.

This reaction was continued until the physical properties of the product remained essentially unchanged. The addition of material from the storage vessel was stopped while the CO ₂ addition continued and the material in the 4 liter reactor was brought to pH 7.0, at which time the CO ₂ addition was stopped and 2.2: 1 A CaCO ₃ / fiber composite was produced, and CaCO ₃ had a well-defined declinated trihedral morphology.

Example 5
The trigonal polyhedral CFSTR / surfactant 15 liters of water and 3 kilograms of CaO are reacted at 48 ° C. to produce a Ca (OH) ₂ slake, and an additional 6 liters of water is added to give 20 wt% A Ca (OH) ₂ lake was produced. A 20% Ca (OH) ₂ lake was sieved through -325 mesh and transferred to a 30 liter reactor (615 rev / min). 0.015 wt% citric acid of the total theoretical CaCO ₃ to be produced was added to the 30 liter reactor and the temperature of the contents was brought to 35 ° C. Begin the addition of 20% CO ₂ gas in air (14.08 standard liters CO ₂ /56.30 standard liters air) to a 30 liter reactor, 5: 1 Ca (OH) ₂ / CaCO _Three slurries were produced. At this point, the CO ₂ gas supply was stopped and the Ca (OH) ₂ / CaCO ₃ slurry was transferred to a 20 liter stirred storage vessel.

2 liters of 0.25 liter Ca (OH) ₂ / CaCO ₃ slurry combined with 0.66 liter 3.8 wt% fiber and 1.09 liter water in a 4 liter stirred storage vessel was produced in the _{Ca (OH) 2 / CaCO 3} / fiber material.

2 liters of Ca (OH) ₂ / CaCO ₃ / fiber material was transferred to a 4 liter stainless steel double jacketed, stirred (1250 rev / min) reactor and the temperature was brought to 58 ° C. Ca and _(OH) 2 / CaCO ₃ / fiber material and air _20% CO 2 (1.30 standard liters _CO 2 /5.23 standard liter minute air) was allowed to react until pH 7.0.

  At this point, 16 liters of 1.5 wt% fiber (6.32 liters of 3.8% consistency fiber and 9.68 liters of water) and a separate 10 liter container of water were prepared. 0.04% surfactant was added based on fiber volume at 1.5% consistency. The surfactant is Tergitol ™ MIN-FOAM 2X, which is commercially available from Union Carbide, Oldridgebury Road 39, 06817, Danbury, Connecticut.

When pH 7.0 was achieved in a 4 liter reactor, the remaining 5: 1 Ca (OH) ₂ / CaCO ₃ slurry was transferred from a 20 liter stirred storage vessel to 176.48 ml /% of 1.5% fiber mixture. with minute flow, and with 32.00Ml / min of water to 10 liters container, CO ₂ gas flow at a rate to maintain conductivity of approximately 90 percent ionic saturation (1.30 standard liters _CO 2/5. 23 standard liters of air) was started while adding to a 4 liter reactor while maintaining a mass balance of about 4-5% total solids. The addition of material from the stirred storage vessel to the reactor was continued until the physical properties of the product remained essentially unchanged. At that point, the addition of material from the storage vessel was stopped while CO ₂ addition continued to pH 7.0, at which time CO ₂ addition was stopped. This produced a 2.33: 1 CaCO ₃ / fiber composite, and the calcium carbonate had a well-defined declinated trihedral morphology.

Example 6
A trihedral polyhedral CFSTR / polyacrylamide 15 liters of water and 3 kilograms of CaO are reacted at 48 ° C. to produce a Ca (OH) ₂ slake, and an additional 6 liters of water is added to form 20 wt% Ca. (OH) A _two- lake was produced. The 20% Ca (OH) ₂ lake was then screened with -325 mesh to produce a screened lake, which was transferred to a 30 liter stirred (615 rpm) reactor. 0.1 wt% citric acid of all theoretical CaCO ₃ to be produced was added to the 30 liter reactor and the temperature of the contents was brought to 50 ° C. Begin the addition of 20% CO ₂ gas in air (15.01 standard liters CO ₂ /60.06 standard liters air) to a 30 liter reactor, 5: 1 Ca (OH) ₂ / CaCO _Three slurries were produced. The CO ₂ gas supply was stopped, the slurry was transferred to a stirred storage container 20 liters. To a 4 liter stirred vessel, add 0.31 liter of Ca (OH) ₂ / CaCO ₃ slurry, 0.60 liter of 3.8% consistency fiber and 1.09 liter of water to add Ca ( _OH) to generate the 2 / CaCO ₃ / fiber material. 2 liters of Ca (OH) ₂ / CaCO ₃ / fiber material was transferred to a 4 liter stirred (1250 rev / min) reaction vessel and the temperature was brought to 51 ° C. The addition of 20% CO _{2 in} air (1.34 standard liters CO ₂ /5.34 standard liters of air) was started until pH 7.0 was achieved, resulting in a CaCO ₃ / fiber composite.

  At this point, 16 liters of 1.5 wt% fiber (6.32 liters of 3.8% consistency fiber and 9.68 liters of water) and a separate 10 liter container of water were prepared. 0.05% cationic polyacrylamide (Percol 292) was added based on the fiber volume at 1.5% consistency. Percoll 292 is commercially available from Allied Colloids, 23434, Suffolk, Virginia.

Once pH 7.0 is achieved in a 4 liter reactor, the remaining 5: 1 Ca (OH) ₂ / CaCO ₃ slurry is transferred from a 20 liter stirred storage vessel at 90 ml / min of 1.5% fiber mixture. CO ₂ gas flow at a rate that maintains a conductivity of about 90% ionic saturation (with 1.30 standard liters CO ₂ /5.23 standard liters) with a flow of water and with additional water at 48.5 ml / min. Add to a 4 liter stirred double jacketed reactor while maintaining the mass balance of the reaction maintaining the product concentration at about 4-5% solids. Started. The addition of material from the stirred storage vessel to the reactor was continued until the physical properties of the product remained essentially unchanged. The addition of material from the 20 liter storage vessel was stopped while the CO ₂ addition was continued until pH 7.0, at which time the CO ₂ addition was stopped and 3.34: 1 CaCO ₃ / fiber composite. The material was produced and the PCC had a well-defined declinated trihedral morphology.

The control fibers of the present invention were refined to 80 ° SR (approximately) using an Escherwis (conical) refiner at the Empire State Paper Research Institute (ESPRI). The control fiber was 200-400 microns as measured by a fiber analyzer (using arithmetic means).

Control Filler-Fiber Making Make a 15% solids slake and mix with the fiber (~ 1.5% consistency). React to a pH end point of 7.0 in the presence of CO ₂ to produce a filler-fiber composite with a specific surface area of 6-11 m ² / g (approximately 60-80% PCC, but composite Can have more or less PCC).

モルホロジー制御された充填材−繊維複合材は、対照の充填材−繊維に比べて同等以上の物性（すなわち引張強度、破壊長および内部結合強度）を示した。

Morphologically controlled filler-fibre composites showed physical properties (ie, tensile strength, fracture length, and internal bond strength) that were equal to or better than the control filler-fiber.

モルホロジー制御された充填材−繊維複合材は、対照の充填材−繊維に比べて同等の光学特性（すなわちＩＳＯ不透明度および顔料散乱）を示した。

Morphologically controlled filler-fiber composites showed comparable optical properties (ie, ISO opacity and pigment scattering) compared to the control filler-fiber.

Claims (30)

(A) supplying a seed-containing lake to the first stage reactor;
(B) reacting the slake containing the seed in the first stage reactor in the presence of carbon dioxide to produce a first partially converted calcium hydroxide calcium carbonate slurry;
(C) reacting the first partially converted calcium hydroxide slurry in the second stage reactor in the presence of carbon dioxide and heel to provide a second partially converted hydroxide Producing a calcium calcium carbonate slurry; and (d) charging the second partially converted calcium hydroxide calcium carbonate slurry in the third stage reactor in the presence of carbon dioxide and fibers Filler-fiber composite comprising producing a material-fiber composite. The filler-fiber composite of claim 1, wherein the fibers are about 0.1 microns to about 2 microns thick and about 10 microns to about 400 microns long. The filler-fiber composite of claim 2, wherein the filler is aragonite and has a specific surface area of about 5 square meters / gram to about 11 square meters / gram. The filler-fiber composite of claim 3, wherein the calcium hydroxide slurry is converted from about 20% to about 40%. The filler-fiber composite of claim 4, wherein the first partially converted calcium hydroxide calcium carbonate slurry is converted from about 41% to about 99%. 6. The filler-fiber composite of claim 5, wherein the second partially converted calcium hydroxide calcium carbonate slurry is converted to a filler-fiber composite. (A) supplying a seed-containing lake to the first stage reactor;
(B) reacting the slake containing the seed in the first stage reactor in the presence of carbon dioxide to produce a first partially converted calcium hydroxide calcium carbonate slurry;
(C) reacting the first partially converted calcium hydroxide slurry in the second stage reactor in the presence of carbon dioxide and heel to provide a second partially converted hydroxide Producing a calcium calcium carbonate slurry; and (d) charging the second partially converted calcium hydroxide calcium carbonate slurry in the third stage reactor in the presence of carbon dioxide and fibers A method of manufacturing a filler-fiber composite comprising producing a material-fiber composite. 8. The method of making a filler-fiber composite of claim 7, wherein the fibers are about 0.1 microns to about 2 microns thick and about 10 microns to about 400 microns long. 9. The method of making a filler-fiber composite according to claim 8, wherein the filler is aragonite and has a specific surface area of about 5 square meters / gram to about 11 square meters / gram. The method for producing a filler-fiber composite of claim 9, wherein the calcium hydroxide slurry is converted from about 20% to about 40%. The method of producing a filler-fiber composite of claim 10, wherein the first partially converted calcium hydroxide calcium carbonate slurry is converted from about 41% to about 99%. The method for producing a filler-fiber composite according to claim 11, wherein the second partially converted calcium hydroxide calcium carbonate slurry is converted to a filler-fiber composite. The filler-fiber composite according to claim 1 used in paper or paperboard. 8. Filler-fiber composite according to claim 7, used in paper or paperboard. A paper produced using the filler-fiber composite according to claim 1. A paper manufactured using the filler-fiber composite according to claim 7. (A) supplying a seed-containing lake to the first stage reactor;
(B) reacting the seed-containing lake in the presence of carbon dioxide in a first stage reactor to produce a first partially converted calcium hydroxide calcium carbonate slurry; and (c) the Reacting the first partially converted calcium carbonate slurry in the second stage reactor in the presence of carbon dioxide and fibers to produce a filler-fiber composite;
Filler-fiber composite comprising The filler-fiber composite of claim 17, wherein the fibers are about 0.1 microns to about 2 microns thick and about 10 microns to about 400 microns long. 19. The filler-fiber composite of claim 18, wherein the filler is aragonite and has a specific surface area of about 5 square meters / gram to about 11 square meters / gram. 20. The filler-fiber composite of claim 19, wherein the calcium hydroxide slurry is converted from about 20% to about 40%. 21. The filler-fiber composite of claim 20, wherein the first partially converted calcium hydroxide calcium carbonate slurry is converted to a filler-fiber composite. (A) supplying a seed-containing lake to the first stage reactor;
(B) reacting the seed-containing lake in the presence of carbon dioxide in a first stage reactor to produce a first partially converted calcium hydroxide calcium carbonate slurry; and (c) the Reacting the first partially converted calcium carbonate slurry in the second stage reactor in the presence of carbon dioxide and fibers to produce a filler-fiber composite;
A method for producing a filler-fiber composite material comprising: 23. The method of making a filler-fiber composite of claim 22, wherein the fibers are about 0.1 microns to about 2 microns thick and about 10 microns to about 400 microns long. 24. The method of making a filler-fiber composite of claim 23, wherein the filler is aragonite and has a specific surface area of about 5 square meters / gram to about 11 square meters / gram. The method for producing a filler-fiber composite according to claim 24, wherein the calcium hydroxide slurry is converted from about 20% to about 40%. The method for producing a filler-fiber composite according to claim 25, wherein the first partially converted calcium hydroxide calcium carbonate slurry is converted into a filler-fiber composite. 18. Filler-fiber composite according to claim 17, used in paper or paperboard. 23. Filler-fiber composite according to claim 22, used in paper or paperboard. A paper produced using the filler-fiber according to claim 17. 23. Paper manufactured using the filler-fiber of claim 22.