Organic compounds -- part of the class 532-570 series – Organic compounds – Carbohydrates or derivatives
Reexamination Certificate
1999-02-08
2001-03-06
Wilson, James O. (Department: 1623)
Organic compounds -- part of the class 532-570 series
Organic compounds
Carbohydrates or derivatives
C536S031000, C536S032000, C536S056000, C536S058000, C536S123100, C536S124000
Reexamination Certificate
active
06197950
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to cationized hydroxy-alkylcelluloses which are useful as components of shampoos, rinses, treatments, etc. and a process for producing the same.
2. Prior Art
Cationized hydroxyalkylcelluloses are known as components of shampoos, rinses, treatments, etc., since they contain quaternary ammonium groups as substituents. When employed as components of shampoos, rinses, treatments, etc., these cationized hydroxyalkylcelluloses should be highly compatible with surfactants which are employed as the principal components therein.
As a process for the production of cationized hydroxyalkylcelluloses, JP-B 45-20318 has disclosed a process comprising using cellulose as the starting material, adding an etherifying agent and a cationizing agent successively or simultaneously thereto and thus effecting a continuous reaction. However, this process is not advantageous economically, since the etherifying agent and the cationizing agent are each utilized only at a poor efficiency. Moreover, there arises another problem that it is highly troublesome to eliminate the unreacted materials and impurities formed in large amounts as by-products.
Meanwhile, JP-B 59-42681 has disclosed a process with the use of an ethylene oxide derivative or a propylene oxide derivative of cellulose as the starting material. Although a cationizing agent can be utilized at a high efficiency in this process, it is necessary in this process to react and wash again a cellulose ether which has once reacted and washed, i.e., the reaction and washing should be performed twice. In this process, a solvent mixture of isopropanol with water is used as a reaction solvent in most cases. When, however, the obtained product has a high degree of hydroxylalkyl-substitution, it is dissolved in the above reaction solvent. As a result, it becomes difficult to stir the reaction system due to the increased viscosity, which brings about a decrease in the conversion.
Further, in the prior art, there has not been developed so far any process by which the above-mentioned problems can be solved and cationized hydroxyalkylcelluloses having a high compatibility with surfactants can be constantly supplied.
DISCLOSURE OF THE INVENTION
An object of the present invention is to provide cationized hydroxyalkylcelluloses which are highly compatible with surfactants and useful as components of hair care products such as shampoos.
Another object of the present invention is to provide a process for producing these cationized hydroxyalkylcelluloses.
The present invention provides a cationized hydroxyalkylcellulose having a glucose unit represented by the following formula (I):
wherein R
1
, R
2
and R
3
represent hydrogen atom, a group represented by the following formula (II):
wherein R
4
represents hydrogen atom or methyl; and “a” is a number of from 1 to 6 on the average, or represented by the following formula (III):
wherein R
4
represents hydrogen atom or methyl; “a” is a number of from 1 to 6 on the average; R
5
, R
6
and R
7
are the same as or different from each other and represent a C
1-16
alkyl; X represents a halogen; and “n” is a number of from 50 to 2,000, the cationized hydroxyalkyl cellulose having a mobility distribution (&Dgr;U), determined by electrophoresis, in the range of from 0.1×10
5
to 2.0×10
5
cm
2
/sec·V, including the above shown group (III) to have a nitrogen atom content (%) of from 0.1 to 10. 0.
The present invention further provides a process for producing a cationized hydroxyalkylcellulose, comprising the steps of mixing a hydroxyalkylcellulose with an aqueous solution of isopropyl alcohol or an aqueous solution of t-butyl alcohol; adding an alkali to the mixture; effecting cationization; and effecting neutralization.
DETAILED DESCRIPTION OF THE INVENTION
The cationized hydroxyalkylcellulose of the present invention is one represented by the formula (I) wherein R
1
, R
2
and R
3
represent hydrogen, a group represented by the formula (II) or another group represented by the formula (III).
It is preferable that the substituent represented by the formula (II) has an average degree of substitution per glucose unit ranging from 0.4 to 2.9 and an average mole number ranging from 1.0 to 7.0. It is still preferable that the substituent represented by the formula (II) has an average degree of substitution per glucose unit ranging from 0.7 to 2.1 and an average mole number ranging from 1.6 to 3.6.
Although the upper limit of “a” in the substituent represented by the formula (II) is not specified theoretically, it is preferable that “a” ranges from 1 to 6 on the average.
The substituent represented by the formula (III) has an average degree of substitution per glucose unit ranging from 0.1 to 3.0, preferably from 0.1 to 1.5 and still preferably from 0.1 to 0.9.
Although the upper limit of “a” in the substituent represented by the formula (III) is not specified theoretically, it is preferable that “a” ranges from 1 to 6 on the average.
In the substituent represented by the formula (III), R
5
, R
6
and R
7
are the same as or different from each other and represent a C
1-6
alkyl, preferably methyl or ethyl.
In the formula (I), “n” represents a number of from 50 to 2,000, preferably from 50 to 1,500. Examples of the halogen represented by X in the formula (I) include chlorine, bromine and iodine.
The cationized hydroxyalkylcellulose represented by the formula (I) has a mobility distribution (&Dgr;U) determined by electrophoresis of from 0.1×10
5
to 2.0×10
5
cm
2
/sec·V, preferably from 0.1×10
5
to 1.5×10
5
cm
2
/sec·V. By regulating &Dgr;U to be within the range as specified above, the compatibility of the hydroxyalkylcellulose with surfactants can be elevated.
It is preferable that the cationized hydroxyalkylcellulose represented by the formula (I) has a nitrogen atom content (%) of from 0.1 to 10.0, still preferably from 0.5 to 4.0.
It is preferable that the cationized hydroxyalkylcellulose represented by the formula (I) has a degree of substitution by a quaternary nitrogen-containing group of from 0.1 to 1.5, still preferably from 0.1 to 0.9.
Moreover, it is preferable that the cationized hydroxyalkylcellulose represented by the formula (I) has a viscosity at 25° C. of from 30 mPa·s (as a 2% by weight aqueous solution; 30 rpm) to 5,000 mPa·s (as a 1% by weight aqueous solution; 30 rpm), still preferably from 70 mPa·s (as a 2% by weight aqueous solution; 30 rpm) to 2,500 mPa·s (as a 1% by weight aqueous solution; 30 rpm).
Next, the process for producing the cationized hydroxyalkylcellulose of the present invention will be illustrated. Since the production process of the present invention is characterized by the type and concentration of an organic solvent solution employed in the reaction, it is not particularly restricted in other treating procedures and conditions. That is, the present invention also involves in its scope any usual modification made by those skilled in the art in producing cationized hydroxyalkylcelluloses.
In the first step, a hydroxyalkylcellulose is mixed with an aqueous solution of isopropyl alcohol or an aqueous solution of t-butyl alcohol.
The hydroxyalkylcellulose to be used in this step can be obtained by a conventional method comprising, for example, treating cellulose with an alkali and then adding an alkylene oxide thereto. As the cellulose employed as the starting material, use may be made of cotton linters, wood pulp, etc.
As the aqueous solution of isopropyl alcohol, it is preferable to use one having an isopropyl alcohol concentration of from 75 to 90% by weight, still preferably from 80 to 90% by weight. As the aqueous solution of t-butyl alcohol, it is preferable to use one having a t-butyl alcohol concentration of from 70 to 85% by weight, still preferably from 75 to 85% by weight.
It is preferable that the aqueous solution of isopropyl alcohol or the aqueous solution of t-butyl alcohol is employed in an amount of from 300 to 900 parts by weight per 100 parts by weigh
Nakamura Hiroyuki
Sato Shigenobu
Daicel Chemical Industries Ltd.
Flynn, Theil, Boutell & Tanis, P.C.
Wilson James O.
LandOfFree
Cationized hydroxyalkylcellulose and process for producing... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Cationized hydroxyalkylcellulose and process for producing..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Cationized hydroxyalkylcellulose and process for producing... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2491530