WO2005047385A1

WO2005047385A1 - Starch compositions and use in cellulosic webs and coatings

Info

Publication number: WO2005047385A1
Application number: PCT/US2004/031901
Authority: WO
Inventors: Kevin Anderson; Kioh Hwang
Original assignee: Cargill, Incorporated
Priority date: 2003-11-07
Filing date: 2004-09-29
Publication date: 2005-05-26

Abstract

There are disclosed modified starch compositions comprising a first modified starch product that may preferably be a hydrophobic starch, a cationic starch, an oxidized starch, a hydroxyalkylated starch, a grafted starch interpolymer, or a mixture thereof, and a second modified starch product, that is modified in a different manner than, and has a viscosity that is less than the viscosity of, the first modified starch product. Also disclosed is a process for using the modified starch compositions in preparing cellulosic webs, particularly paper, and the resultant cellulosic webs. There are also disclosed coatings comprising the novel modified starch compositions and the use thereof in coating substrates such as paper.

Description

STARCH COMPOSITIONS AND USE IN CELLULOSIC WEBS AND COATINGS

This application claims the priority of provisional U.S. Patent Application Serial Number 60/518559 filed November 7, 2003, the entire contents of which are incorporated herein.

FIELD OF THE DISCLOSURE

The present disclosure relates to compositions of starches and the use of the starch compositions in the production of cellulosic webs, particularly paper, and in the production of coatings, particularly for paper.

BACKGROUND

It is well known to utilize starch products for the production of paper and in coatings for paper. Furthermore, the use of compositions of starch products in the production of paper is known from the patent literature, such as for example U.S. Patents Nos. 4,239,592 and 4,872,951. There is, however, a continuing need for developments in the types of materials that can offer utility in the production of paper and other cellulosic products, and in the production of coated paper products.

SUMMARY OF THE DISCLOSURE The present disclosure relates to novel compositions of modified starches and the use of the compositions in the production of cellulosic webs, particularly paper, and in the production of coatings, particularly for paper. In some embodiments, the compositions comprise at least two starch products having different viscosities and having different chemical, physical, or enzymatic modifications. In some embodiments, the compositions comprise a modified starch product that is a hydrophobic starch, a cationic starch, an oxidized starch, a hydroxyalkylated starch, a grafted starch interpolymer, or mixtures thereof, and another starch product having a different modification and having a viscosity value less than the viscosity value of the modified hydrophobic, cationic, oxidized, hydroxyalkylated starch, grafted starch interpolymer,^' or mixtures thereof. The present disclosure also relates, in some embodiments, to cellulosic webs, particularly paper products, that are produced with the novel starch compositions. The present disclosure also relates, in some embodiments, to novel coating compositions prepared using the novel starch compositions, and to paper products coated with the novel coating compositions.

DETAILED DESCRIPTION OF THE DISCLOSURE

The present disclosure relates to novel compositions of modified starches and the use of the compositions in the production of cellulosic webs, particularly paper, and in the production of coatings, particularly for paper, hi some embodiments, the compositions comprise at least two starch products having different viscosities, and having different chemical, physical, or enzymatic modifications. In some embodiments, the compositions comprise a modified starch product that is a hydrophobic starch, a cationic starch, an oxidized starch, a hydroxyalkylated starch, a grafted starch interpolymer, or mixtures thereof, and another starch product having a different modification and having a viscosity value less than the viscosity value of the modified hydrophobic, cationic, oxidized, hydroxyalkylated starch, grafted starch interpolymer, or mixtures thereof. The present disclosure also relates, in some embodiments, to cellulosic webs, particularly paper products, that are produced with the novel starch compositions. The present disclosure also relates, in some embodiments, to novel coating compositions prepared using the novel starch compositions, and to paper products coated with the novel coating compositions. In preparing the modified starch compositions of the present disclosure, one of the modified starch components of the composition has a viscosity value that exceeds the viscosity value of a second modified starch component of the composition and is modified in a different manner. The starch component that has the higher viscosity value may be any modified starch, or mixtures thereof. Preferably however, the modified starch component having the higher viscosity value is a hydrophobic starch, a cationic starch, an oxidized starch, a hydroxyalkylated starch, a grafted starch interpolymer, or mixtures thereof. More details relating to hydrophobic starches, cationic starches, oxidized starches, hydroxyalkylated starches, and grafted starch mterpolymers, are provided below. The modified starch products of the present compositions are modified chemically, physically, or enzymatically, by any methods known in the art. Combinations of the chemical, physical, or enzymatic treatments may also be used to modify the starch. Chemical modification includes any treatment of a starch with a chemical that results in a modified starch. Within chemical modification are included, but not limited to, depolymerization of a starch, oxidization of a starch, reduction of a starch, etherification of a starch, esterification of a starch, nitrification of a starch, defatting of a starch, and the like. Chemically modified starches may also be prepared by using a combination of any of the chemical treatments. Examples of chemically modified starches include, the reaction of octenyl succinic anhydride with starch to produce a hydrophobic esterified starch; the reaction of 2,3-epoxypropyltrimethylammonium chloride with starch to produce a cationic starch; the reaction of ethylene oxide with starch to produce hydroxyethyl starch; the reaction of hypochlorite with starch to produce an oxidized starch; the reaction of an acid with starch to produce an acid depolymerized starch; defatting of a starch with a solvent such as methanol, ethanol, propanol, methylene chloride, chloroform, carbon tetrachloride, and the like, to produce a defatted starch. Physically modified starches are any starches that are physically treated in any manner to provide physically modified starches. Within physical modification are included, but not limited to, thermal treatment of the starch in the presence of water, thermal treatment of the starch in the absence of water, fracturing the starch granule by any mechanical means, pressure treatment of starch to melt the starch granules, and the like. Physically modified starches may also be prepared by using a combination of any of the physical treatments. Examples of physically modified starches include the thermal treatment of starch in an aqueous environment to cause the starch granules to swell without granule rupture; the thermal treatment of anhydrous starch granules to cause polymer rearrangement; fragmentation of the starch granules by mechanical disintegration; and pressure treatment of starch granules by means of an extruder to cause melting of the starch granules. Enzymatically modified starches are any starches that are enzymatically treated in any manner to provide enzymatically modified starches. Within enzymatic modification are included, but not limited to, the reaction of an alpha amylase with starch, the reaction of a protease with starch, the reaction of a lipase with starch, the reaction of a phosphorylase with starch, the reaction of an oxidase with starch, and the like. Enzymatically modified starches may be prepared by using a combination of any of the enzymatic treatments. Examples of enzymatic modification of starch include, the reaction of alpha-amylase enzyme with starch to produce a depolymerized starch; the reaction of alpha amylase debranching enzyme with starch to produce a debranched starch; the reaction of a protease enzyme with starch to produce a starch with reduced protein content; the reaction of a lipase enzyme with starch to produce a starch with reduced lipid content; the reaction of a phosphorylase enzyme with starch to produce an enzyme modified phosphated starch; and the reaction of an oxidase enzyme with starch to produce an enzyme oxidized starch. Preferred for use herein as one of the modified starch components of the starch compositions is a hydrophobic starch, a cationic starch, an oxidized starch, a hydroxyalkylated starch, a grafted starch interpolymer, and mixtures thereof. Preparation of these types of starches are described in detail hereinafter. The hydrophobic starch may be any hydrophobic starch. This includes any starch that is modified in any known manner to render the starch hydrophobic. The term, hydrophobic starch, as used herein, is defined as any starch that will absorb water to an extent less than that of the starch material that has not been rendered hydrophobic. The starch used may be any source of starch such as dent corn, waxy corn, potato, wheat, rice, sago, tapioca, sorghum, sweet potato, or mixtures thereof. For example, a suitable method for preparing a hydrophobic starch is as follows. The starch to be rendered hydrophobic may be any starch. The starch can be modified by introducing a functional group that renders the starch hydrophobic, such as an amine, an ester, or an ether. Alternatively, the starch may be chemically, physically, or enzymatically treated prior to rendering the starch hydrophobic. Furthermore, a hydrophobic starch may be prepared by introducing any functional group such as an amine, an ester, or an ether, to any starch, prior or subsequent to rendering the starch hydrophobic. In more detail, in rendering a starch hydrophobic, any known manner may be utilized. For example, the starch may be esterified or etherified, or the like, to achieve hydrophobicity. Suitable for use as modifying agents to render starches hydrophobic are, but not limited to, an aryl-, alkyl-, alkenyl-, aralkyl-, aralkenyl- anhydride; an aryl-, alkyl-, alkenyl-, aralkyl-, aralkenyl- halogen; an aryl-, alkyl-, alkenyl-, aralkyl-, aralkenyl- ketene dimer; an aryl-, alkyl-, alkenyl-, aralkyl-, aralkenyl- epoxide; an aryl-, alkyl-, alkenyl-, aralkyl-, aralkenyl- ester and acid halide derivatives of carboxylic acids, intramolecular combinations thereof, and mixtures thereof. Preferred modifying agents for rendering the starches hydrophobic are alkenyl succinic anhydrides, particularly octenyl succinic anhydride. Grafted starch interpolymers are also suitable hydrophobic starches. The cationic starch used in the starch compositions of the present disclosure may be any cationic starch. A starch of any source such as dent corn starch, waxy corn starch, potato starch, wheat starch, rice starch, sago starch, tapioca starch, sorghum starch, sweet potato starch, or mixtures thereof, may be used as the starch that is rendered cationic. Cationic starches may be produced by any conventional manner. For example, the cationic starches may be produced by a chemical reaction of the starch with a modifying agent containing an amino, imino, ammonium, sulfonium, or phosphonium group. The chemical reaction may be an esterification or etherification reaction. Preferred for use are the primary, secondary, tertiary or quaternary amino groups, with the tertiary amino and quaternary ammonium starch ethers, such as the quaternary amino alkyl ether of starch, more preferred. If desired, the cationic starch may be treated in any conventional manner with known treating agents to render the cationic starches hydrophobic. The oxidized starch used in the starch compositions of the present disclosure may be any oxidized starch. Oxidized starch may be produced in any conventional manner by the reaction of any starch such as dent corn starch, waxy corn starch, potato starch, wheat starch, rice starch, sago starch, tapioca starch, sorghum starch, sweet potato starch, or mixtures thereof, with any oxidizing agent. Examples of suitable oxidizing agents include metal salts of hypochlorite, metal salts of permanganate, hydrogen peroxide, organic peroxides, peracids, and the like, and mixtures thereof. For example, dent corn starch may be reacted with sodium hypochlorite solution under alkaline pH conditions for a length of time sufficient to achieve a product suitable for use as an oxidized starch. Hydroxyalkylated starches such as hydroxyethyl starch and hydroxypropyl starch may be produced by any conventional manner. For example, hydroxyethyl starch may be produced by the etherification of any starch such as dent corn starch, waxy corn starch, / potato starch, wheat starch, rice starch, sago starch, tapioca starch, sorghum starch, sweet potato starch, or mixtures thereof, with ethylene oxide. Similarly, hydroxypropyl starch may be produced by the etherification of any starch such as dent corn starch, waxy corn starch, potato starch, wheat starch, rice starch, sago starch, tapioca starch, sorghum starch, sweet potato starch, or mixtures thereof, with propylene oxide. In both instances, the starch is treated with the alkylene oxide, under alkaline pH conditions, for a length of time sufficient to achieve a product suitable for use as a hydroxyalkylated starch. Any grafted starch interpolymer may be used in the starch compositions of the present disclosure. The grafting of the starch is a chemical modification of the starch. Additionally, in preparing the grafted starch inteφolymer, the starch component may be chemically, physically, and/or enzymatically modified at the time of the inteφolymerization. The grafted starch inteφolymer is produced using any conventional manner for inteφolymerizing a starch with one or more monomers. The starch utilized in preparing the grafted starch inteφolymer may be obtained from any starch such as dent corn starch, waxy corn starch, potato starch, wheat starch, rice starch, sago starch, tapioca starch, sorghum starch, sweet potato starch, or mixtures thereof. The one or more components that is inteφolymerized with the starch, may be any suitable monomer. Exemplary of suitable monomers include, but are not limited to, the following: vinyl monomers such as alkyl acrylates, hydroxylated alkyl acrylates, alkyl methacrylates, hydroxylated alkyl methacrylates, alkyl vinyl ketones, substituted acrylamides, methacrylic acid, crotonic acid, itaconic acid, fumaric acid, maleic acid, maleic anhydride, vinyl halides, vinylidene halides, vinyl esters, vinyl ethers, vinyl carbazole, N-vinyl pyrrolidone, chlorostyrene, alkyl styrene, ethylene, propylene, isobutylene, vinyl triethoxysilane, vinyl diethylmethylsilane, vinyl methyldichlorosilane, triphenyl vinylsilane, 1 -vinyl- l-methylsila-14-crown-5. Also suitable for use are dienes such as, 1,3 -butadiene, isoprene, chloroprene, cyclobutadiene, and divinyl benzene. The grafted starch inteφolymers may be produced utilizing any conventional manner. For example, a starch may be grafted with at least one or more monomer, in the presence of a free radical initiator. The starch utilized herein may be used in any form such as, for example, gelatinizing the starch to form a starch paste, that is thereafter reacted with at least one monomer. Any suitable temperature and/or pressure may be employed in the reaction. Any suitable ratio of the components utilized in preparing the grafted starch inteφolymer may be used. Any suitable free radical initiator may be used provided that the free radical initiator acts to inteφolymerize and graft the monomers. Exemplary of such initiators are organic and inorganic peroxy compounds, and azo compounds. hi preparing the novel starch compositions of the present disclosure, there is utilized as the other modified starch product any starch modified in a different manner and having a viscosity value that is less than the viscosity value of the first modified starch. The modified starch having the lower viscosity value may be any modified starch prepared from any source such as dent corn starch, waxy corn starch, potato starch, wheat starch, rice starch, sago starch, tapioca starch, sorghum starch, sweet potato starch, or mixtures thereof. The lower viscosity modified starch may be used without any further treatment. Alternatively, the modified starch having the lower viscosity may be a starch that has been modified by any conventional manner such as, for example, by oxidizing, rendering hydrophobic, rendering cationic, alkylating, esterifying, depolymerizing, grafting, and the like, and mixtures thereof. Exemplary of the modified starches having a lower viscosity that may be utilized herein, but not limited thereto, are a dextrin, hydroxyethyl starch, an acid-depolymerized starch, an oxidized starch, an enzyme or ammonium persulfate depolyrnerized starch, a grafted starch inteφolymer, and the like, and mixtures thereof. The viscosity of the starches described herein is determined in accordance with the test procedure described in the Standard Analytical Methods of the Corn Refiners' Association, Inc., CRA Method B-54, using a Brookfield DV-II+ viscometer. In preparing the compositions of the present disclosure, the modified starch component having the greater viscosity value is utilized in an amount ranging from about 1 to about 99% by weight of the composition, preferably about 1 to about 50% by weight, and more preferably from about 1 to about 30% by weight. The modified starch component of the composition modified in a different manner and having the lower viscosity value is utilized in an amount ranging from about 1 to about 99% by weight of the composition, preferably about 50 to about 99% by weight, and more preferably from about 70 to about 99% by weight of the composition. In producing the modified starch compositions of the present disclosure, any conventional method may be used for mixing the modified starch component having the greater viscosity value and the starch component of the composition modified in a different manner and having the lower viscosity value. For example, each of the modified starch components of the composition may be in dry form when mixed together. Alternately, each of the modified starch components of the composition may be in slurry form when mixed together to form the composition. Alternately, one of the modified starch components may be in dry form, and one of the modified starch components may be in slurry form, when the modified starch components are mixed together to form a modified starch composition. Another acceptable method of mixing is to combine the gelatinized starch pastes after the individual starch suspensions have been gelatinized by a cooking process. In another method suitable for use, either the modified starch having the greater viscosity or the modified starch having the lower viscosity may be in a gelatinized starch paste form, when mixed with the other component. As mentioned, any known method for mixing the modified starch components of the composition may be utilized. The modified starch compositions of the present disclosure may be incoφorated into a cellulosic web either during the formation of the web or after the web has been formed in any known manner. Preferably, the cellulosic web is paper. For example, the modified starch compositions may be incoφorated during the formation of the cellulosic web as an addition to the wet-end of a paper machine. The modified starch compositions may also be incoφorated into the pre-formed cellulosic web after the web has been formed, by any known manner such as by spraying. In a preferred embodiment the modified starch compositions of the present disclosure may be incoφorated into a pre-formed cellulosic web in the following manner. The modified starch composition is slurried in water and the resultant slurry is heated at a temperature sufficient to achieve gelatinization of the modified starch slurry, to produce a gelatinized starch paste. Typically, the heating to achieve gelatinization is carried out at a temperature above about 90 °C. The modified starch paste may be incoφorated into the pre-formed cellulosic web by using a size press, tub, gate roll applicator, spraying or calendar stack application. The cellulosic web having the modified starch composition incoφorated therein is then dried in any manner, thereby producing a cellulosic web product. hi producing cellulosic webs incoφorating the modified starch compositions of the present disclosure, either during formation of, or after the cellulosic web has been formed, any suitable amount of the modified starch composition may be incoφorated. Preferably, the amount of modified starch composition incoφorated into the cellulosic web is an amount sufficient that the cellulosic web will have incoφorated therein an amount of the modified starch ranging from about 1 to about 100 kilograms (kg) per metric ton of paper. It has further been observed that paper produced with the modified starch compositions of the present disclosure is generally characterized by not having detrimental effects on printing. In addition, the modified starch compositions of the present disclosure are utilized in the preparation of coatings that may be applied to paper. The modified starch compositions of the present disclosure may be used as a binder in the production of paper coating formulations. Preferably, the modified starch compositions are in a gelatinized form when utilized in the preparation of the paper coatings. Typically, paper coating formulations comprise a pigment such as clay, calcium sulfate, or calcium carbonate; a binder such as latex, polyvinyl alcohol, starch, or protein; and various other additives such as lubricants, insolubilizers, rheology modifiers, optical brighteners, water retention aids, dispersants, biocides, dyes, and the like. It is expected that use of the novel modified starch compositions of the present disclosure in paper coatings will impart improved hydrophobicity, improved ink holdout, and improved printing properties to the coated product. Preferably, the coating is applied to a paper product. Typically, in the production of paper coatings there is utilized a pigment in an amount of about 100 parts. The binder component of the paper coating is typically utilized in an amount of about 5 to about 20 parts based on the pigment. Any other ingredients such as lubricants, rheology modifiers, water retention agents, or the like, that are desired in the paper coating may be utilized in well known conventional amounts, such as 0.5 parts based on the pigment. The coatings incoφorating the novel modified starch compositions may be applied to a surface, such as that of a cellulosic web, in any conventional manner. Typically, the coatings may be applied to a surface by the use of a roll coater, a rod coater, a blade coater, a film press coater, an air knife coater, a curtain coater, a spray coater, and the like. The following examples are presented to illustrate the present disclosure and to assist one of ordinary skill in making and using the same. The examples are not intended in any way to otherwise limit the scope of the disclosure.

EXAMPLES h carrying out the examples, the following test procedures were used.

VISCOSITY Viscosity was determined in accordance with the Standard Analytical Methods of the Com Refiners Association, Inc. Test Procedure CRA-B-54. The instrument utilized in determining viscosity was a Brookfield DV-II+ viscometer.

WATER ABSORBENCY The water absorbency of a sized cellulosic web was determined in accordance with TAPPI Test Method T 432 om-94, with the exception that the test was carried out at 47% relative humidity, at a temperature of 22 °C, and the water drop size was 47 mg ±0.5 mg. The water absorbency test procedure was determined to evaluate the performance of the sizing property.

CANADIAN STANDARD FREENESS Canadian Standard Freeness was determined in accordance with TAPPI Test Method T 227 om-94.

STANDARD CONDITIONING Standard conditioning and testing atmospheres for paper, board, and pulp handsheets, and related products was determined in accordance with TAPPI Test Method T 402 om-93.

INTERNALBOND STRENGTH The internal bond strength was determined in accordance with TAPPI Test Method T 541 om-89. SURFACE STRENGTH OF PAPER (WAX PICK TEST The surface strength of paper was determined in accordance with TAPPI Test Method T 459 om-93.

STARCH PICK-UP The amount of starch pick up by the cellulosic web, for example, paper, was determined by measuring the difference in weight between the base paper and the base paper treated with starch.

ALKENYL SUCCINIC ACID CONTENT A starch is esterified by reaction with an alkenyl succinic anhydride such as octenyl succinic anhydride. To estimate the degree of substitution of alkenyl succinic anhydride treated starch, it is necessary to carry out a titration on the treated starch to estimate the amount of free carboxylic acid groups. Accordingly, to an approximately 2.5 g sample of the anhydride treated starch, in a 100 ml beaker, there was added 12.5 ml of 0.1 N hydrochloric acid. The resulting slurry was agitated for about 30 minutes. The agitated slurry was then vacuum filtered through a Buchner funnel, and the filter cake was washed with 20-30 ml of deionized water until the filtrate showed negative chloride ion as determined with a silver nitrate indicator. The filter cake was then transferred into a 600 ml beaker, where the starch was slurried with 100 ml of deionized water. Thereafter, an additional 200 ml of hot, deionized water was added to the starch slurry. The beaker was placed in a boiling water bath, and heating, with stirring, was carried out for about 10 minutes. The beaker was removed from the water bath and 2 to 4 drops of 1% phenolphthalein indicator in 50% aqueous ethanol, were added. While hot, titration to the first permanent pale pink endpoint was carried out with 0.1 normal sodium hydroxide. The endpoint is defined as one that has a color persistence of at least 15 seconds. The volume of the 0.1 normal sodium hydroxide consumed to reach the end-point is recorded. A titration is performed on the acid depolymerized waxy starch substrate for use as a control. The amount of octenyl succinic acid (OS A) on dry basis, in percent, that was reacted onto the starch is calculated using the following equation: % OSA =

EXAMPLE 1 In this example, there is provided a starch composition comprising a hydrophobic starch having a viscosity that exceeds the viscosity of hydroxyethyl starch. Octenyl succinic anhydride treated starch, that is hydrophobic, was prepared by the following method. Acid depolymerized waxy starch, available from Cargill, Inc. as CALIBER^® 180, having a viscosity of about 450 cps (centipoise), as measured according to the Standard Analytical Methods of the Com Refiners Association, Inc. CRA-B-54, except for the following: the sample was measured at 18% solids, and cooled to 49 °C. There was slurried 200 grams of the CALIBER^® 180 acid depolymerized waxy starch in 340 ml of deionized water in a 2L four neck round bottom flask. The flask was equipped with an inlet from a syringe pump for addition of octenyl succinic anhydride, an inlet connected to a pump for addition of 3% aqueous sodium hydroxide to adjust pH, a thermometer, and a mechanical stirrer. To the starch slurry was added, with stirring, at a rate of 3 ml/hr, and at a temperature of about 32 °C to 35 °C, an amount of 6.18 grams of 2-octenyl-l -succinic anhydride, available from Sigma- Aldrich Coφoration. During the addition of the octenyl succinic anhydride, the pH of the slurry was maintained at 8.0 to 8.3, utilizing the 3% aqueous sodium hydroxide solution as needed. After the anhydride addition was completed, the slurry was stirred for an additional four hours while maintaining the pH at about 8.0 to 8.3, at a temperature of about 32 °C to 35 °C. After completion of the reaction, the heating source was removed. The slurry was acidified to a pH of about 6.3, with a 5% hydrochloric acid solution. The slurry was filtered, and the resultant filter cake was washed three times, each time with 300 ml of deionized water, and then air-dried. The resultant octenyl succinic anhydride treated starch was determined to have an octenyl succinic acid content of 2.6% and a viscosity of about 490 cps, as measured according to the Standard Analytical Methods of the Com Refiners Association, Inc. CRA-B-54, except for the following: the sample was heated to 90 °C for 4 minutes, cooled to 49 °C for 11 minutes, measured at 2% solids, using spindle 21, at 20 φm (revolutions per minute). In preparing the starch composition, 10% by weight of the octenyl succinic anhydride treated acid depolymerized waxy starch, having a viscosity of about 490 cps, measured at 2% solids, using spindle 21 at 20 φm, at 49 °C, was mixed with 90 % by weight of Cargill's FILM FLEX 70 hydroxyethyl starch having a viscosity of about 440 cps, as measured according to the Standard Analytical Methods of the Corn Refiners Association, Inc. CRA-B-54, except for the following: the sample was heated at 90 °C for 4 minutes, followed by cooling to 49 °C for 11 minutes, measured at 20% solids, using spindle 21 at 20 φm. It should be noted that the viscosities of the two starch components of the composition were determined at different solids levels. Accordingly, in order to evaluate viscosities of the two starch components on an equal comparative basis, the viscosity of the hydroxyethyl starch, if determined at a 2% solids level, all other conditions being equal, would be lower than the viscosity value of the octenyl succinic anhydride treated acid depolymerized waxy starch. The starch composition of this example was produced by grinding the starch composition for about two minutes, and thereafter transferring the ground starch composition into a bottle and shaking the bottle containing the starch composition for an additional ten minutes. The resulting composition of starches was determined to have a viscosity of about 490 cps, as measured according to the Standard Analytical Methods of the Com Refiners Association, h e. CRA-B-54, except for the following: the sample was heated at 90 °C for 4 minutes, followed by cooling to 49 °C for 11 minutes, measured at 15% solids, using spindle 21 at 20 φm. Prior to utilizing the starch composition of the example for sizing paper, the starch composition, as a 10% solids starch slurry, was heated for ten minutes at a temperature near the boiling point, and then cooled to room temperature, resulting in a gelatinized starch paste solution. For this example, blotter paper was used as a base paper to which the sizing starch paste was applied, h applying the sizing starch paste to the blotter paper, a K-Hand Coater, available from R.K. Print Coat Instrument Ltd. (United Kingdom), was used. An excess of the 10% starch paste was applied to the blotter paper, and drawn with a K-Bar to spread the starch layer evenly on the paper. The amount of starch on the paper was controlled with K-Bars of varying sizes to produce paper with different amounts of starch pick up as reported in the following Table 1. The sized paper was dried at 40 °C in a forced air oven overnight. Edges of the paper were trimmed to remove areas where any irregular deposition of starch may have occurred. The sized paper was weighed and the area was measured. The amount of starch pick up on the paper was calculated from the weight difference after sizing. The water absorbency of the sized paper was determined and reported in the following Table 2.

Table 1. Amount of Starch Pick up on the Paper

Table 2. Time for Water Absorbency [TAPPI 432om-94]

From the above data, it is observed that the paper was sized, as is evidenced by the increased average water absorbency in time value. EXAMPLE 2 In this example, there is provided a composition comprising an oxidized starch having a viscosity that exceeds the viscosity of hydroxyethyl starch. A composition of an oxidized starch and a hydroxyethyl starch was prepared from a 26.67 g sample of Cargill's FILM FLEX^® 20 hydroxyethyl starch, with a viscosity of 413 cps (as measured according to the Standard Analytical Methods of the Com Refiners Association, Inc. CRA-B-54, except for the following: the sample was heated at 90 °C for 4 minutes, followed by cooling to 49 °C for 11 minutes, measured at 7% solids, using spindle 21 at 20 φm), and a 6.67 g sample of Cargill's SUPERFILM^® 270W oxidized starch with a viscosity of 400 cps (as measured according to the Com Refiners Association standard method number B-54 Standard Analytical Methods of the Com Refiners Association, hie. CRA-B-54, except for the following: the sample was heated at 97 °C for 10 minutes, followed by cooling to 49 °C for 9 minutes, measured at 22% solids, using spindle 21 at 50 φm). The composition was prepared by mixing the dry starch components in a 600 ml beaker. The composition comprises 80% of the hydroxyethyl starch and 20% of the oxidized starch. It should be noted that the viscosity of the two starch components of the composition, were determined at different solids levels. Accordingly, in order to evaluate viscosities of the two starch components on an equal comparative basis, the viscosity of the oxidized starch, if determined at a 7% solids level, all other conditions being equal, would be lower than the value of 413 cps determined at the 7% solids level for the hydroxyethyl starch. The dry starch composition was slurried in water to a total weight of 200 g to prepare a 15% dry basis slurry. The slurry was heated and stirred on a stirring hotplate, to boiling. Boiling was continued for 10 minutes to produce a gelatinized starch paste, which was then cooled to 49 °C in a warm water bath. A portion of the starch paste was then added to the top edge of a pre- weighed standard blotter paper and the paste was drawn down with Bar no. 5 of the K-Bar set. The resultant sized sheet was then dried for a period of 10 minutes on an Emerson Speed Dryer, available from Emerson Apparatus, at a temperature of 93 °C. The sheet was then transferred to a Noram Lorentzen & Wettre handsheet press, and pressed overnight with no additional pressing pressure applied. The sheet was then re- weighed to determine starch pick-up. Sizing response was determined according to TAPPI 432 om-94 utilizing a 40 mg test drop and recording the time from contact to disappearance of the drop into the sheet. A blank blotter sheet was used as a control. Four drops were measured across the center of the sized sheet. The results are summarized in Table 3.

Table 3. Starch Pick-up and Time for Water Absorbency [TAPPI 432 om-94]

From the above data, it is observed that the paper was sized, as is evidenced by the increased water absorbency in time value.

EXAMPLE S In this example, there is provided a composition comprising a cationic starch having a viscosity that exceeds the viscosity of hydroxyethyl starch.

(a) Preparation of a cationic starch product having a higher viscosity A 2.2 kg sample of CHARGE +310 waxy cationic starch, available from Cargill, Inc., was slurried in water to achieve a 20 Baume suspension. With mixing, the suspension was heated to 38 °C in a hot water bath. After the suspension temperature was attained, 37% hydrochloric acid was added to achieve a pH of 1.0. The suspension was reacted for 6 hours, at which time the starch was depolymerized. A 20% sodium carbonate solution was added slowly to the suspension to achieve a pH of 5.5. The reacted starch suspension was filtered to a cake on a vacuum Buchner funnel. The resultant starch cake was washed with one bed volume of deionized water, and the resultant washed starch cake was allowed to air dry to an equilibrium moisture level. The viscosity of the resultant cationic starch product was measured according to the Standard Analytical Methods of the Com Refiners Association, Inc. CRA-B-54, except for the following: the sample was heated at 97 °C for 8 minutes, followed by cooling to 49 °C for 9 minutes, measured at 7% solids, using spindle 21 at 20 φm. The viscosity of the starch product was determined to be 280 cps.

(b) Determination of viscosity of hydroxyethyl starch The viscosity of FILM FLEX 70 hydroxyethyl starch, available from Cargill, Inc., was determined in accordance with the Standard Analytical Methods of the Com Refiners Association, Inc. CRA-B-54 except for the following: the sample was heated at 90 °C for 4 minutes, followed by cooling to 49 °C for 11 minutes, measured at 20% solids, using spindle 21 at 20 φm. The viscosity was determined to be 400 cps. It should be noted that the viscosity of the two starch components of the composition were determined at different solids levels. Accordingly, in order to evaluate viscosities of the two starch components on an equal comparative basis, the viscosity of the hydroxyethyl starch, if determined at a 7% solids level, all other conditions being equal, would be lower than the value of 280 cps determined at the 7% solids level for the CHARGE + 310 cationic waxy starch.

(c) Preparation of a composition comprising a cationic starch and a hydroxyethyl starch wherein the cationic starch has a higher viscosity 200 g of Cargill's CHARGE +310 cationic waxy starch of section (a) was dry mixed with 800 g of Cargill's FILM FLEX 70 hydroxyethyl starch of section (b) in a 1 kg sample container and shaken for approximately 5 minutes. A 12% dry basis slurry of the composition was prepared and the viscosity was measured according to the Standard Analytical Methods of the Com Refiners Association, Inc. CRA-B-54, except for the following: the sample was heated at 90 °C for 4 minutes, followed by cooling to 49 °C for 11 minutes, using spindle 21 at 20 φm. A viscosity of 720 cps was determined.

(d) Production of paper utilizing the composition of Example 3c. The composition in section (c) comprising 20% of Cargill's CHARGE +310 cationic waxy starch and 80% of Cargill's FILM FLEX 70 hydroxyethyl starch was utilized in the preparation of paper as follows. Paper was produced on a pilot Fourdrinier paper machine (available for use at Western Michigan University). The paper furnish consisted of an 80% hardwood, 20% softwood mix refined to a Canadian Standard Freeness of 400. Inorganic filler was added in an amount equal to 15% based on the fiber weight. The inorganic filler consisted of ground calcium carbonate and precipitated calcium carbonate in respectively, a 1 :4 ratio. Alkenyl succinic anhydride was added to the furnish for internal sizing. Cargill's CHARGE +310 cationic waxy starch was added as a wet end starch at a rate of 0.5% based on the fiber weight to the furnish. The paper furnish was then introduced into the Fourdrinier paper machine and a continuous paper web having a basis weight of 150 g/m² was produced. The continuous web containing no size press starch was used as the control in this example. The effects resulting from the use of the starch composition of Example 3c were shown as follows. In utilizing the starch composition of Example 3c, the starch composition was slurried in water to 20% solids and jet cooked at a temperature of 260 °F, thereby yielding a gelatinized starch paste. The starch composition was utilized herein in the form of a cooked starch paste at two solids levels, one at 5% solids and the other at 14.4% solids. The cooked starch pastes were separately introduced into the continuous paper web that was produced, after the continuous paper web had been dried. The cooked starch pastes were introduced utilizing a puddle size press. Thereafter the continuous paper web containing the starch pastes, was then re-dried to a level of approximately 5% moisture. The resultant starch sized continuous paper web was collected at the paper machine reel and conditioned according to TAPPI Standard Method T402 om-93 for subsequent testing. The results of the testing are reported in Table 4.

Table 4. Paper testing results

It is observed from the data in Table 4 that the paper products containing starch pastes are characterized by having improved internal bond strength and improved surface strength as compared with the control paper product in the absence of size press starch. As the data indicates, the internal bond strength of the paper was increased by approximately 20%. Moreover, the surface strength of the paper was improved by approximately 400% or greater.

EXAMPLE 4 In this example, the procedure of Example 2 is followed except that the starch composition of Example 2 is replaced by the starch composition of the present example. In this example there is provided a starch composition comprising 20% of Cargill's FILM FLEX 20 hydroxyethyl starch and 80% of Cerestar's CFILM TCF 07311 thermally modified starch. CFILM TCF 07311 is a starch that has been physically modified by anhydrous heat treatment in the presence of an acid. The viscosity of the FILM FLEX 20 hydroxyethyl starch exceeds the viscosity of the CFILM TCF 07311 thermally modified starch. The starch composition is prepared by dry mixing the components until a suitable mixture is obtained.

The starch composition is heated to a temperature sufficient to achieve a gelatinized starch paste. It is expected that a paper product prepared using the starch paste of this example will be sized.

EXAMPLE 5 In this example, the procedure of Example 2 is followed except that the starch composition of Example 2 is replaced by the starch composition of the present example. In this example there is provided a composition comprising 35% of Cargill's SUPERFILM 235 oxidized starch and 65% of Cargill's CALIBER 183 acid depolymerized waxy starch wherein the viscosity of the oxidized starch exceeds the viscosity of the acid depolymerized starch. The starch composition is prepared by dry mixing the components until a suitable mixture is obtained. The starch composition is heated to a temperature sufficient to achieve a gelatinized starch paste. It is expected that a paper product prepared using the starch paste of this example will be sized.

EXAMPLE 6 In this example there is provided a composition comprising 10% of Cargill's CHARGE +310 cationic starch and 90% of an alpha amylase enzyme depolymerized com starch wherein the viscosity of the cationic starch exceeds the viscosity of the alpha amylase enzyme depolymerized starch. The cationic starch is prepared by the reaction of (3-chloro-2-hydroxypropyl) trimethylammonium chloride with a waxy com starch, in slurry form, under alkaline conditions for a length of time sufficient to produce a cationic starch. The slurry is then brought to a neutral pH, and filtered to a cake. The cake is washed with water, and the resultant washed cake is dried. The starch product is then slurried in water to a desired solids level and heated to gelatinization to form a starch paste. The alpha-amylase enzyme depolymerized com starch is prepared by slurrying com starch in water to a solids level of approximately 20% and adding approximately 0. /o w/w amount of alpha amylase. The starch slurry, containing the alpha amylase enzyme, is then depolymerized by heating to approximately 75 °C, and the temperature is maintained until the desired viscosity that is less than the viscosity of the cationic starch, is achieved. The depolymerization reaction is then stopped by heating to a temperature above 90 °C to deactivate the enzyme. The cationic starch is heated to a temperature sufficient to achieve a gelatinized starch paste. The cationic starch, in gelatinized paste form, and the alpha amylase enzyme depolymerized starch, also in gelatinized paste form, are mixed to provide a mixture wherein the viscosity of the cationic starch product exceeds the viscosity of the alpha amylase enzyme depolymerized starch product. The resultant starch paste is incoφorated into a paper product. It is expected that a suitably sized paper product will be obtained.

EXAMPLE 7 hi this example, the procedure of Example 2 is followed except that the starch composition of Example 2 is replaced by the starch composition of the present example. In this example, there is provided a starch composition comprising a hydrophobic starch that has a viscosity exceeding the viscosity of a cationic starch. The hydrophobic starch is prepared by the reaction of (2,2,3 ,3 ,4,4,5,5,5- nonafluoropentyι)oxirane with a potato starch, in slurry form, under alkaline conditions. The resultant slurry is then brought to a neutral pH, and is filtered to a cake. The cake is washed with water, and the resultant washed cake is dried. The composition also comprises a cationic starch prepared by the reaction of (3- chloro-2-hy(froxγpropyl)dimethyldodecylammonium chloride with tapioca starch, in slurry form, under alkaline conditions to achieve a desired substitution level. The resultant slurry is then brought to an acidic pH with hydrochloric acid, and the slurry is allowed to react to produce a depolymerized cationic starch. The slurry is then brought to a neutral pH thereby stopping the depolymerization. The slurry is filtered to a cake and the cake is washed with water. The resultant washed cake is dried. A starch composition is prepared by dry mixing 15% of the hydrophobic starch with 85%o of the cationic starch product to provide a mixture wherein the viscosity of the hydrophobic starch product exceeds the viscosity of the cationic starch product. The starch composition is heated to a temperature sufficient to achieve a gelatinized starch paste. It is expected that a paper product prepared using the starch paste of this example will be sized. I

EXAMPLE 8 In this example, there is provided a starch composition comprising an esterified starch that has a viscosity exceeding the viscosity of a grafted starch inteφolymer. The esterified starch of the composition is prepared by the reaction of acetic anhydride with waxy com starch, in slurry form, under alkaline conditions at a pH of 8 to 8.5, and at a temperature of about 80 °F. The resultant slurry is then brought to a neutral pH, and filtered to a cake. The cake is washed with water, and the resultant cake is dried. The acetylated starch product is heated to gelatinization at a desired solids level to form a paste. The composition also comprises a grafted starch inteφolymer prepared by the reaction of acrylonitrile with an acid depolymerized dent com starch, that is heated to a temperature sufficient to achieve a gelatinized starch paste, in the presence of a free radical initiator. A free radical quenching agent is then added to stop the free radical reaction when the desired degree of polymerization is reached. The resultant product is a gelatinized grafted starch inteφolymer paste. The gelatinized acetylated starch paste is mixed with the gelatinized grafted starch inteφolymer paste to provide a composition wherein the viscosity of the acetylated starch exceeds that of the grafted starch inteφolymer. The grafted starch inteφolymer paste and the acetylated starch paste are mixed in a ratio of 1 : 1. It is expected that a paper product prepared using the composition, in paste form, of this example will be sized.

EXAMPLE 9 In this example, there is provided a composition comprising a grafted starch inteφolymer that has a viscosity exceeding the viscosity of Cargill's FILM FLEX 70 hydroxyethyl starch. The grafted starch inteφolymer is prepared by the reaction of styrene, butadiene, and a dent com starch, heated to a temperature sufficient to achieve a gelatinized starch paste, in the presence of a free radical initiator. A free radical quenching agent is then added to stop the free radical reaction when the desired degree of polymerization is reached. The resultant product is a gelatinized grafted starch inteφolymer paste. A suspension of FILM FLEX 70 hydroxyethyl starch is heated to gelatinization to form a starch paste.

The gelatinized FILM FLEX 70 starch paste is mixed with the gelatinized grafted starch inteφolymer paste to provide a composition wherein the viscosity of the grafted starch inteφolymer paste exceeds the viscosity of the hydroxyethyl starch paste. The grafted starch inteφolymer paste and the FILM FLEX 70 starch paste are mixed in a ratio of 25:75 respectively. It is expected that a paper product prepared using the composition of this example will be sized. PAPER COATINGS EXAMPLE 10 In this example, there is shown the preparation of a paper product coated with a composition of the present disclosure. More particularly, the composition utilized herein comprises 10% by weight of the octenyl succinic anhydride treated acid depolymerized waxy starch of Example 1, having a viscosity of about 490 cps (as measured according to the Standard Analytical Methods of the Com Refiners Association, Inc. CRA-B-54, except for the following: the sample was heated to 90 °C for 4 minutes, followed by cooling to 49 °C for 11 minutes, measured at 2% solids, using spindle 21 at 20 φm) mixed with 90 % by weight of Cargill's FILM FLEX 70 hydroxyethyl starch having a viscosity of about 440 cps (as measured according to the Standard Analytical Methods of the Com Refiners Association, Inc. CRA-B-54, except for the following: the sample was heated to 90 °C for 4 minutes, followed by cooling to 49 °C for 11 minutes, measured at 20% solids, using spindle 21 at 20 φm). The composition is heated to a temperature sufficient to achieve a gelatinized starch paste. The starch paste is utilized as a binder in preparing the coating to be applied to the paper. In preparing the coating composition, there is utilized, in addition to the binder, a clay pigment, a water retention agent, and a lubricant. The clay pigment is present in an amount of 100 parts. The binder is present in an amount of 15 parts based on the pigment. The other components in the coating are present in an amount up to 2 parts. The coating formulation is prepared by mixing the components to achieve a suitable dispersion.

The coating formulation is applied to a paper substrate by means of a film press applicator at an application rate of 5 g/m². The resultant coated paper is expected to have suitable properties.

EXAMPLE 11 In this example, there is utilized a paper coating composition that contains a gelatinized starch paste as produced in Example 4. The paper coating comprises, in addition to the gelatinized starch paste that is used as a binder, a pigment consisting of 80 parts clay and 20 parts calcium carbonate. The coating further contains a rheology modifier and a lubricant. The coating formulation comprises 100 parts pigment, 12 parts binder, with the other components present in an amount up to about 3 parts. The resultant coating formulation is then applied to a paper substrate. The coating is applied by means of a blade coater at an application rate of 6 g/m². It is expected that the resultant coated paper product will have suitable characteristics. The invention has been described with reference to various specific and illustrative embodiments and techniques. However, one skilled in the art will recognize that many variations and modifications may be made while remaining within the spirit and scope of the invention.

Claims

CLAIMSWhat is claimed is:

1. A composition comprising an amount of from about 1% to about 99% by weight of a first modified starch product, and an amount of from about 1% to about 99% by weight of a second modified starch product that is modified in a different manner than the first modified starch product, and has a viscosity that is less than the viscosity of the first modified starch product, as determined in accordance with the Standard Analytical Methods of the Com Refiners Association, Inc., Test Procedure CRA-B-54, utilizing a Brookfield DV-II+ viscometer.

2. The composition according to Claim 1 wherein the modification of the starches is selected from the group consisting of chemical modification, physical modification, enzymatic modification, and mixtures thereof.

3. The composition according to Claim 2 wherein the modification of the starch is chemical modification.

4. The composition according to Claim 3 wherein the chemical modification of the starch is selected from the group consisting of depolymerization, oxidation, reduction, etherification, esterification, nitrification, defatting, and mixtures thereof.

5. The composition according to Claim 2 wherein the modification of the starch is physical modification.

6. The composition according to Claim 5 wherein the physical modification of the starch is selected from the group consisting of thermal treatment, fracturing by mechanical means, pressure treatment, and mixtures thereof.

7. The composition according to Claim 2 wherein the modification of the starch is enzymatic modification.

8. The composition according to Claim 7 wherein the enzymatic modification of the starch is selected from the group consisting of reaction with an alpha amylase enzyme, reaction with a protease enzyme, reaction with a lipase enzyme, reaction with a phosphorylase enzyme, reaction with an oxidase enzyme, and mixtures thereof.

9. The composition according to Claim 1 wherein the first modified starch product is selected from the group consisting of a hydrophobic starch, a cationic starch, an oxidized starch, a hydroxyalkylated starch, a grafted starch inteφolymer, and mixtures thereof.

10. The composition according to Claim 1 wherein the first modified starch product is present in an amount ranging from about 1% to about 50% by weight, and the second modified starch product is present in an amount ranging from about 1% to about 50% by weight.

11. The composition according to Claim 9 wherein the first modified starch product is a hydrophobic starch.

12. The composition according to Claim 9 wherein the first modified starch product is a cationic starch.

13. The composition according to Claim 9 wherein the first modified starch product is an oxidized starch.

14. The composition according to Claim 9 wherein the first modified starch product is a hydroxyalkylated starch.

15. The composition according to Claim 9 wherein the first modified starch product is a grafted starch inteφolymer.

16. The composition according to Claim 9 wherein the first modified starch product is a hydrophobic starch, and the second modified starch product is hydroxyethyl starch.

17. The composition according to Claim 9 wherein the first modified starch product is a cationic starch, and the second modified starch product is hydroxyethyl starch.

18. The composition according to Claim 9 wherein the first modified starch product is a hydroxyalkylated starch, and the second modified starch product is a thermally modified starch.

19. The composition according to Claim 9 wherein the first modified starch product is a cationic starch, and the second modified starch product is a thermally modified starch. i

20. The composition according to Claim 9 wherein the first modified starch product is a hydrophobic starch, and the second modified starch product is a thermally modified starch.

21. A process for preparing a cellulosic web that comprises incoφorating into the cellulosic web a composition comprising an amount of from about 1% to about 99% by weight of a first modified starch product, and an amount of from about 1% to about 99%o by weight of a second modified starch product that is modified in a different manner than the first modified starch product, and has a viscosity that is less than the viscosity of the first modified starch product, as determined in accordance with the Standard Analytical Methods of the Com Refiners Association, Inc., Test Procedure CRA-B-54, utilizing a Brookfield DV-II+ viscometer.

22. The process according to Claim 21 wherein the modification of the starches is selected from the group consisting of chemical modification, physical modification, enzymatic modification, and mixtures thereof.

23. The process according to Claim 22 wherein the modification of the starch is chemical modification selected from the group consisting of depolymerization, oxidation, reduction, etherification, esterification, nitrification, defatting, and mixtures thereof.

24. The process according to Claim 22 wherein the modification of the starch is physical modification selected from the group consisting of thermal treatment, fracturing by mechanical means, pressure treatment, and mixtures thereof.

25. The process according to Claim 22 wherein the modification of the starch is enzymatic modification selected from the group consisting of reaction with an alpha amylase enzyme, reaction with a protease enzyme, reaction with a lipase enzyme, reaction with a phosphorylase enzyme, reaction with an oxidase enzyme, and mixtures thereof.

26. The process according to Claim 21 wherein the first modified starch product is selected from the group consisting of a hydrophobic starch, a cationic starch, an oxidized starch, a hydroxyalkylated starch, a grafted starch inteφolymer, and mixtures thereof.

27. The process according to Claim 21 wherein the cellulosic web is a paper product.

28. The process according to Claim 21 wherein the first modified starch product is present in an amount ranging from about 1% to about 50% by weight, and the second modified starch product is present in an amount ranging from about 1% to about 50% by weight.

29. The process according to Claim 26 wherein the first modified starch product is a hydrophobic starch, and the second modified starch product is hydroxyethyl starch.

30. The process according to Claim 26 wherein the first modified starch product is a cationic starch, and the second modified starch product is hydroxyethyl starch.

31. The process according to Claim 26 wherein the first modified starch product is a hydroxyalkylated starch, and the second modified starch product is a thermally modified starch.

32. The process according to Claim 26 wherein the first modified starch product is a cationic starch, and the second modified starch product is a thermally modified starch.

33. The process according to Claim 26 wherein the first modified starch product is a hydrophobic starch, and the second modified starch is a thermally modified starch.

34. The process according to Claim 21 wherein the composition is incoφorated into the cellulosic web in an amount sufficient that the cellulosic web comprises from about 1 to about 100 kg of the composition per metric ton of the cellulosic web.

35. A product comprising a cellulosic web and a composition comprising an amount of from about 1% to about 99% by weight of a first modified starch product, and an amount of from about 1% to about 99% by weight of a second modified starch product that is modified in a different manner than the first modified starch product, and has a viscosity that is less than the viscosity of the first modified starch product, as determined in accordance with the Standard Analytical Methods of the Com Refiners Association, Inc., Test Procedure CRA-B-54, utilizing a Brookfield DV-II+ viscometer.

36. The product according tα Claim 35 wherein the composition is present in an amount sufficient that the cellulosic web comprises from about 1 to about 100 kg of the composition per metric ton of the cellulosic web.

37. The product according to Claim 35 wherein the modification of the starches is selected from the group consisting of chemical modification, physical modification, enzymatic modification, and mixtures thereof.

38. The product according to Claim 37 wherein the modification of the starch is chemical modification selected from the group consisting of depolymerization, oxidation, reduction, etherification, esterification, nitrification, defatting, and mixtures thereof.

39. The product according to Claim 37 wherein the modification of the starch is physical modification selected from the group consisting of thermal treatment, fracturing by mechanical means, pressure treatment, and mixtures thereof.

40. The product according to Claim 37 wherein the modification of the starch is enzymatic modification selected from the group consisting of reaction with an alpha amylase enzyme, reaction with a protease enzyme, reaction with a lipase enzyme, reaction with a phosphorylase enzyme, reaction with an oxidase enzyme, and mixtures thereof.

41. The product according to Claim 35 wherein the first modified starch product is selected from the group consisting of a hydrophobic starch, a cationic starch, an oxidized starch, a hydroxyalkylated starch, a grafted starch inteφolymer, and mixtures thereof.

42. The product according to Claim 35 wherein the cellulosic web is a paper product.

43. The product according to Claim 35 wherein the first modified starch product is present in an amount ranging from about 1% to about 50% by weight, and the second modified starch product is present in an amount ranging from about 1% to about 50% by weight.

44. The product according to Claim 41 wherein the first modified starch product is a hydrophobic starch, and the second modified starch product is hydroxyethyl starch.

45. The product according to Claim 41 wherein the first modified starch product is a cationic starch, and the second modified starch is hydroxyethyl starch.

46. The product according to Claim 41 wherein the first modified starch product is a hydroxyalkylated starch, and the second modified starch product is a thermally modified starch.

47. The product according to Claim 41 wherein the first modified starch product is a cationic starch, and the second modified starch product is a thermally modified starch.

48. The product according to Claim 41 wherein the first modified starch product is a hydrophobic starch, and the second modified starch is thermally modified starch.

49. A coating composition comprising a pigment, and a composition comprising an amount of from about 1% to about 99% by weight of a first modified starch product, and an amount of from about 1% to about 99% by weight of a second modified starch product that is modified in a different manner than first modified starch product, and has a viscosity that is less than the viscosity of the first modified starch product, as determined in accordance with the Standard Analytical Methods of the Com Refiners Association, Inc., Test Procedure CRA-B-54, utilizing a Brookfield DV-II+ viscometer.

50. The coating composition according to Claim 49 wherein the modification of the starches is selected from the group consisting of chemical modification, physical modification, enzymatic modification, and mixtures thereof.

51. The coating composition according to Claim 50 wherein the modification of the starch is chemical modification selected from the group consisting of depolymerization, oxidation, reduction, etherification, esterification, nitrification, defatting, and mixtures thereof.

52. The coating composition according to Claim 50 wherein the modification of the starch is physical modification selected from the group consisting of thermal treatment, fracturing by mechanical means, pressure treatment, and mixtures thereof.

53. The coating composition according to Claim 50 wherein the modification of the starch is enzymatic modification selected from the group consisting of reaction with an alpha amylase enzyme, reaction with a protease enzyme, reaction with a lipase enzyme, reaction with a phosphorylase enzyme, reaction with an oxidase enzyme, and mixtures thereof.

54. The coating composition according to Claim 49 wherein the first modified starch product is selected from the group consisting of a hydrophobic starch, a cationic starch, an oxidized starch, a hydroxyalkylated starch, a grafted starch inteφolymer, and mixtures thereof.

55. The coating composition according to Claim 54 wherein the first modified starch product is a hydrophobic starch, and the second modified starch product is hydroxyethyl starch.

56. The coating composition according to Claim 54 wherein the first modified starch product is a hydroxyalkylated starch, and the second modified starch product is a thermally modified starch.

57. The coating composition according to Claim 49 wherein the pigment is present in an amount of about 100 parts, and the composition is present in an amount of about 5 to about 20 parts based on the pigment.

58. The coating composition according to Claim 49 wherein the first modified starch product of the composition is present in an amount ranging from about 1% to about 50%) by weight, and the second modified starch product of the composition ranges from about 1% to about 50% by weight.

59. A product comprising a cellulosic web coated with a coating composition comprising a pigment, and a composition comprising an amount of from about 1% to about 99%o by weight of a first modified starch product, and an amount of from about 1% to about 99% by weight of a second modified starch product that is modified in a different manner than the first modified starch product, and has a viscosity that is less than the viscosity of the first modified starch product, as determined in accordance with the Standard Analytical Methods of the Com Refiners Association, Inc., Test Procedure CRA-B-54, utilizing a Brookfield DV-II+ viscometer.

60. The product according to Claim 59 wherein the modification of the starches is selected from the group consisting of chemical modification, physical modification, enzymatic modification, and mixtures thereof.

61. The product according to Claim 60 wherein the modification of the starch is chemical modification selected from the group consisting of depolymerization, oxidation, reduction, etherification, esterification, nitrification, defatting, and mixtures thereof.

62. The product according to Claim 60 wherein the modification of the starch is physical modification selected from the group consisting of thermal treatment, fracturing by mechanical means, pressure treatment, and mixtures thereof.

63. The product according to Claim 60 wherein the modification of the starch is enzymatic modification selected from the group consisting of reaction with an alpha amylase enzyme, reaction with a protease enzyme, reaction with a lipase enzyme, reaction with a phosphorylase enzyme, reaction with an oxidase enzyme, and mixtures thereof.

64. The product according to Claim 59 wherein the first modified starch product is selected from the group consisting of a hydrophobic starch, a cationic starch, an oxidized starch, a hydroxyalkylated starch, a grafted starch inteφolymer, and mixtures thereof.

65. The product according to Claim 59 wherein the pigment is present in an amount of about 100 parts, and the composition is present in an amount of about 5 to about 20 parts based on the pigment.