JP2831465B2 - Nylon filament dyeing method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a filament for a toothbrush.

Background of the Invention U.S. Pat. No. 4,802,255 to Breuer et al. Describes a nylon monofilament containing at least two colored areas, one of which is provided by a dye. The monofilament is contained in the bristles of the toothbrush and when the toothbrush is used by the owner, the color intensity of the stained area changes depending on the wear, giving an indication when the toothbrush should be replaced. Breuer et al. List six food dyes or coloring agents that can be used for dyeing monofilaments, including indigotine (FD & C Blue No. 2), and the conditions that can be used for dyeing in column 4 are listed. Widely described. Breuer et al. Also provide specific examples of a number of staining methods, including three examples using indigotine as a dye (Examples 4-6).

The particular staining method described by Breuer et al. Was for laboratory samples. However, in order to produce sufficient quantities of dyed filaments for commercial toothbrushes, there is a need for methods that can be used to dye large quantities of filaments. The method should be cost effective and, of course, should produce nylon filaments with a consistent level of dye penetration throughout.

SUMMARY OF THE INVENTION In general, the present invention is a method for dyeing a batch of nylon filaments for a toothbrush. The batch used here is at least 2 pounds of nylon filament. The method comprises the steps of converting a batch of first nylon filaments to an aqueous solution containing 0.01 to 0.05% w / v indigotin dye for 10 minutes to
Including soaking for 80 minutes. The solution should have a pH between 2.5 and 4.5 and have a temperature between 70C and 85C. When immersing nylon filament,
The dye penetrates the outer cross-sectional area but not the inner cross-sectional area. The batch of first nylon filaments can be removed from the solution and used on the bristles with a wear indicating toothbrush. The same method is repeated for the second batch of nylon filaments, reusing the same solution. Preferably, the same solution is then used to dye additional batches. Preferably, the staining step is performed at atmospheric pressure and
Takes less than a minute and the nylon filament has a diameter of 0.00
5 inches to 0.014 inches.

The method can be used to produce commercial quantities of nylon filament for use in a wear indicating toothbrush in a cost effective manner. For example, the method can be used for batches of nylon filaments of 10-40 pounds, even for batches of 100 pounds or more. Importantly, the same solution can be reused at least once, even up to 5 or 6 times, and still produce filaments in which the indigotine dye has penetrated a uniform and consistent cross-sectional area. This method is easy to perform, safe and provides a stable dye solution.

Other advantages of the invention will be apparent from the description of preferred embodiments, and from the claims.

BEST MODE FOR CARRYING OUT THE INVENTION Dyed wear indicating nylon monofilaments, toothbrushes containing such monofilaments, and methods of making toothbrushes are described in detail in Breuer et al.

The staining solution used in the method of the present invention is indigotin 0.
Contains 01-0.05% w / v. If too much indigotine is used, too much dye will penetrate the filament too far. If too little dye is used, too little dye may penetrate and the solution may not be reusable. The reason is that the initial batch of filaments may absorb a limited amount of dye present.

The temperature of the solution should be between 70C and 85C. Too high a temperature causes the water to evaporate quickly, making the dye more concentrated and the dye being picked up too quickly, making the penetration less controllable. Too low temperatures result in too slow dye pick-up.

The dyeing process is preferably performed at atmospheric pressure to avoid having to use large pressurized equipment in the plant.

Indigotine is a stable acid dye and the solution is
Should be acidic.

The volume of the dyeing solution should be large enough so that the first batch of filaments does not absorb the high percentage of dye in the solution such that the solution cannot be reused to dye the second batch.

Nylon filaments, most preferably monofilaments, should have a diameter commonly used in toothbrushes and most preferably have 0.008 or 0.009 inches.

Nylon filaments should be immersed in the solution long enough to obtain adequate dye penetration of the filament's outer cross-sectional diameter to provide good wear indicating properties. Preferably, the immersion time should be as limited as possible,
Should be less than one hour.

A detailed description of the most preferred method is given below, beginning with a description of the equipment and solutions used, describing the method.

The dyeing process is performed in a 633 gallon whiting stainless steel tank with side dimensions of 30 "x 40" x 130 ".

The staining solution used in the tank was 633 gallons of distilled water, 7.7 liters of glacial acetic acid, and 555 g of 100% pure indigotine.
Is included. Maintain the temperature of the solution at 75 ° C ± 1.5 ° C.

Two 633 gallon rinse tanks will also be used. Fill the first tank with tap water. The second tank is filled with tap water mixed with 1.5 liters of Dow Corning # 24 silicone emulsion.

The monofilament used is 8 feet long and diameter
A 0.008 inch Wytex 6.12S nylon skein (bundle) is about 10 pounds. The skein should be siliconized, annealed, wetted and combed before dyeing according to standard methods. Hanks should not be dried before use.

Dyeing method 1) Dip four skeins completely in the dye solution.

2) Set the timer for 45 minutes.

3) Lift the skein every 1.5 minutes and re-soak to allow circulation of dye between filaments.

4) After 45 minutes, remove the skein and transfer to the first rinse tank. Rinse by soaking 4-5 times.

5) Transfer it to the second rinse tank. Continue rinsing by soaking another 4-5 times. This rinsing will restore finishes lost during the dyeing process.

6) Comb (recomb) the skein again and dry /
Continue to use the packaging method.

7) Using the same solution, repeat the method four times for additional batches of skeins. After dyeing the five skeins, change the dye solution and the first rinse solution. Change the second rinse solution daily.

In some cases, the method comprises applying a series of skeins to 80 ° C ± 1.5.
It can be corrected by immersing in a staining solution heated to ° C. for 30 minutes. In addition, the method can be used to stain ten skeins at a time as opposed to four skeins.

 Other embodiments are within the claims.

Claims (8)

(57) [Claims] (A) immersing a first batch of nylon filaments in an aqueous solution containing 0.01 to 0.05% w / v indigotin dye for 10 minutes to 80 minutes, said solution having a pH of 2.5 to 4.5 and C. to 85.degree. C., wherein the indigotin dye penetrates the nylon filament consistently to color the uniform outer cross-sectional area of the nylon filament, and the inner cross-sectional area of the nylon filament has (B) removing the first batch of nylon filaments from the solution and removing the first batch having the outer cross-sectional area colored with the indigotin dye and the inner cross-sectional area not colored with the indigotine dye; Providing a dyed nylon filament; (c) securing said first dyed nylon filament to the head of a first toothbrush; (d) the same before The solution was reused, nylon filaments second batch and the second toothbrush for step (a), the
(B) and (c) are repeated to provide first and second toothbrushes, each toothbrush consistently penetrating said indigotin dye into said nylon filament, and the same exterior of said nylon filament in each said toothbrush. A method of dyeing a nylon filament and fixing the same to a toothbrush, wherein the cross-sectional area is uniformly colored. 2. The steps of (a), (b) and (c) are repeated for the third batch of nylon filaments and the third toothbrush by reusing the same solution to form the first, second and third toothbrushes. 2. The method of claim 1, further comprising the step of providing each toothbrush with a consistent amount of said indigotin dye penetrating said nylon filament throughout said nylon filament to uniformly color said same external cross-sectional area of said nylon filament in each toothbrush. The method described in. 3. The same solution is reused to repeat steps (a), (b) and (c) for a fourth batch of said nylon filaments and a fourth toothbrush, wherein the first, second, third and Including an additional step of providing a fourth toothbrush,
3. The method of claim 2, wherein each toothbrush consistently penetrates the same amount of the indigotin dye into the nylon filament to uniformly color the same external cross-sectional area of the nylon filament in each toothbrush. 4. The method of claim 1, wherein step (a) is performed at atmospheric pressure. 5. The method according to claim 1, wherein the nylon filament has an average diameter of 0.
Having 127-0.356mm (0.005 inch-0.014 inch),
The method of claim 1. 6. The method of claim 1, wherein said first nylon filament and said second nylon filament are monofilaments. 7. The method of claim 1, wherein said first nylon filament is immersed in said aqueous solution for less than 60 minutes. 8. The first batch of nylon filaments weighs at least 10 pounds.
The method of claim 1.