JPS6235793B2 - - Google Patents

Description

[Detailed description of the invention]

In the present invention, polyester fiber cotton with high heat shrinkability is wrapped in a wrapping machine for forming futon cotton or on a card and formed into the shape of a futon (hereinafter, the product formed into the shape of a futon is referred to as a wrap), and then heated using a hot air circulation type heat treatment machine. This invention relates to a method for manufacturing a polyester fiber padding for a futon, which prevents the futon from sagging when worn by shrinking the staple fibers constituting the wrap and reducing the bulk of the wrap through high-temperature heat treatment. During heat treatment, by adjusting the static pressure difference in the heat treatment zone in the hot air circulation heat treatment machine to a certain range,
The object of the present invention is to provide cotton padding for a futon that maintains the bulk and texture of the futon in an optimal state and has an excellent texture. Futons made of polyester fibers have shown a tendency to rapidly increase in use in recent years due to the advantages of being lightweight, dustproof, washable and hygienic, and due to the lack of natural fibers. however,
It has the disadvantage of so-called "settling" in which the bulk decreases as it is worn, and mattresses in particular have a strong tendency to sag due to the state of wear, and mattresses made of 100% polyester fiber are generally Currently, it is used in combination with cotton, rather than as a standard. Therefore,
In order to eliminate this sagging caused by wearing, a wrap made of highly heat-shrinkable polyester fiber cotton that is spread and molded into the shape of a futon is exposed to a sufficiently high temperature and heat treated to remove the staple fibers that make up the wrap. It is effective to shrink it. The reason for this will be explained next. The settling of futon padding made of polyester fiber cotton when worn generally has a strong correlation with the specific volume at the time of initial load, and as shown in Figure 1, the smaller the specific volume at the time of initial load, the more the repeated compression increases. The sag, expressed as the rate of decrease in bulk, becomes smaller. Therefore, in order to prevent the futon from sagging when worn, it is found that it is most effective to reduce the specific volume of the polyester fiber cotton used at the time of initial load. Here, the specific volume at initial load is defined as the raw cotton to be measured is carded to create a web, the web is cut to 20cm x 20cm, and stacked to weigh 80g.
A plate measuring 20 cm x 20 cm and weighing 170 g is placed on this sample, the heights of the four corners of the sample are measured in cm, and the average value _H1 is calculated using the following formula:
This value represents the bulkiness of the futon immediately after it is molded. Specific volume at initial load = 20 x 20 x H ₁ /80 (cm ² /g
) Next, to determine the rate of decrease in bulk due to repeated compression, the plate used to measure the specific volume at initial load was placed on another sample prepared in the same manner as used for measuring the specific volume at initial load above, and the plate used to measure the specific volume at initial load was placed on a 15 kg sample. A weight with a weight of 10
The sample is repeatedly compressed and recovered using a device that places the load on the plate for 1 second, that is, on the entire sample, and lifts it vertically until it leaves the plate for the next 10 seconds. Read the height, and the height is 99, which is the height at the time of recovery 100 times ago.
It is calculated using the following formula from the height H ₂ when it is within % and H ₁ when the specific volume at initial load is measured. Decreasing rate of bulk due to repeated compression = H ₁ - H ₂ /H ₁ × 100 (%) On the other hand, in the case of polyester fiber cotton, as shown in Figure 2, it is understood that the specific volume at initial load depends on the number of crimps. Therefore, in order to reduce the specific volume at initial load, the number of crimps must be increased. However, with currently commonly used manufacturing methods, it is nearly impossible to increase the number of crimps to an extent that can prevent the sagging, which is the objective of the present invention.
In order to compensate for these drawbacks, we use polyester fibers with high heat shrinkage performance, with a heat shrinkage rate of 10% or more when treated at 170°C for 15 minutes, and preferably at 130°C or more, preferably at 140°C after forming the wrap. It is effective to reduce the specific volume at initial load by performing heat treatment at the above temperature. However, when the polyester fiber cotton is used and heat treated by the method described above,
Depending on the heat treatment equipment and heat treatment conditions,
It has been found that the bulk cannot be reduced sufficiently, resulting in products that have a large amount of sagging, and in other cases, products that have an extremely hard texture and are unsuitable as futons. As a result of intensive research to solve the above-mentioned problems in the development and production of such futons, the present inventors have found that, regardless of the mixing ratio of various polyester cottons or polyester cottons and other futon cottons, First, by adjusting the static pressure difference in the heat treatment zone within a limited range, a futon with a good texture can be obtained.
It has been discovered that these problems can be solved. A hot air circulation heat treatment machine is a heat treatment machine in which the object to be heat treated is placed on a wire mesh or a perforated plate, and hot air is passed over the object for a certain period of time, in which the air passes from the primary side to the secondary side. The resulting pressure loss creates a static pressure difference between the primary and secondary sides. The present invention provides a futon padding that prevents sagging and has a good feel by keeping this static pressure difference within a certain range. In other words, polyester fiber cotton with a high shrinkage performance of 10% or more and cotton containing 30% or more are passed through a wrapping machine or card for futon forming, and after being formed into a futon shape, it is processed using a hot air circulation heat treatment machine. 130
In the method of performing high-temperature treatment above ℃, the static pressure difference P (mm
12/R-9≦P≦21/R+9 A method for producing padding cotton for futons, which is characterized in that Ag) is adjusted to a range that satisfies the relational expression 12/R-9≦P≦21/R+9 with the mixing ratio R of the high shrinkage fibers. . The present inventors have found that by selecting a static pressure difference within a specific range based on the mixing ratio of the highly heat-shrinkable polyester cotton of the present invention from the examples described later, the present inventors have found that by selecting a static pressure difference within a specific range, the futon has less set and is equivalent to or better than a futon made of 100% Deci cotton. This substantially proves that it is possible to obtain a comforter with an excellent feel, and the method of the present invention provides a comforter with less sagging, which could not be obtained by using conventional polyester fibers. Moreover, it is possible to obtain futon filling cotton with a good texture. Next, the basis for obtaining the formula of the present invention will be explained.
FIG. 3 shows data obtained by the present inventors in Examples using the polyester fiber under various conditions.
The value of the static pressure difference is plotted against the cotton blend ratio, and the observation results of the texture and degree of settling of the cotton padding for futons are shown in the figure with a symbol of ○ for good results and an x symbol for poor results. . As is clear from the figure, when the static pressure difference P is small, the feel of the futon is generally soft and it is difficult to obtain a futon with little sagging, which is the objective of the present invention, and the mixing ratio R of the high heat shrinkable cotton of the present invention is As the size decreases, P must be increased in order to obtain a futon that satisfies the texture. Next, if P is too large, the feel of the futon will be too hard and inappropriate, and as R increases, the value of P that will provide a suitable feel becomes smaller.
Furthermore, if R is less than 0.3, the set will become large regardless of P or the hand will deteriorate significantly.
From the above, the value of P that allows you to obtain a futon with less sagging and excellent texture is 0.3≦R≦1.0 in relation to R, and the most probable value as the lower limit of P is P≧12 /R-9, and the most probable value P≦21/R+9 indicating the upper limit of P. The static pressure difference described above changes depending on the hot air velocity, the degree of opening of the wire mesh or perforated plate of the heat treatment machine, the thickness of the object to be heat treated, and the resistance to passage of the hot air due to density, etc. In other words, Normally, the degree of opening of the wire mesh and the perforated plate is constant, so the magnitude of the static pressure difference is determined by the resistance of the object to be treated through which the air passes and the speed of the hot air. Furthermore, in general, the resistance of air passing through the object to be treated is constant when manufacturing a certain type of futon, so in this case the static pressure difference can only be changed by the wind speed. It is generally known that the static pressure difference is adjusted by changing the air volume by adjusting the rotational speed of the blower or the opening degree of a damper installed in the circulating air passage. In the present invention, a remarkable improvement effect is exhibited when polyester fiber is used as the main filler, but an improvement effect is also observed when conventionally used desiccant cotton or the like is mixed as necessary. Next, the present invention will be explained in detail with reference to Examples.
The present invention is not limited to the following examples.
In addition, in the examples, the evaluation of the padded cotton was based on the feel of a futon made from desiccated cotton. Example 1 The intrinsic viscosity (measured at 20°C using a mixed solvent of phenol and tetrachloroethane at a weight ratio of 1:1) was
Using two kinds of chips of high viscosity and low viscosity polyethylene terephthalate of 0.685 and 0.485, a single hole output rate of 4.0 g/min ( High and low viscosity (2.0g/min each), spinning speed 800m/min, spinning temperature 275℃
The resulting undrawn tow was spun at 100 m/min.
After stretching at a stretching speed of , it was dried at 70° C. and cut into 75 mm pieces to obtain composite crimped cotton (referred to as A cotton). The fineness of this cotton is 12.9 denier.
The heat shrinkage rate measured at 170°C was 24.5%.
Furthermore, the above-mentioned unstretched tow is stretched in the same manner,
After heat setting and drying at 150°C, cotton cut to 75 mm (referred to as B cotton) was obtained. The fineness of this cotton was 15.2 denier and the heat shrinkage rate was 1.5%. Next, the obtained A cotton and B cotton were mixed in the proportions shown in Table 1, and the mixture was put through a lap picking machine to yield 1.8 kg of cotton per 1 m ² (hereinafter referred to as basis weight).
After obtaining a lap, each lap was sequentially placed in a hot air circulation heat treatment machine adjusted to 140℃, and thoroughly heat treated.The amount of circulating hot air was varied using a damper, depending on each sample. The static pressure difference created by the lap was read using a water column manometer. The texture of each piece thus obtained was measured by touch. These results are shown in Table 1 and plotted in FIG.

【table】

[Table] Example 2 Using a hollow fiber spinneret from polyethylene terephthalate chips with an intrinsic viscosity of 0.690, a single hole output rate of 3.3 g/min and a spinning speed of 1000 m/min were obtained using a normal spinning machine.
The hollow fibers were spun at a spinning temperature of 275°C, collected and drawn at a speed of 100m/min, and then spun at 70°C.
By drying and cutting into 75 mm pieces, hollow high shrinkage cotton (referred to as C cotton) was obtained. The fineness of this cotton is
It had a denier of 8.1 and a heat shrinkage rate of 17.5%. In addition, using the same chips as above, we produced a yarn with a heat shrinkage rate of 4.5% with a denier of 10.0 using the normal spinning and drawing method.
cotton (referred to as D cotton) was obtained. Next, the obtained C and D cottons were mixed in the proportions shown in Table 2, and then heat treated in the same manner as in Example 1, and the texture was observed. The results are shown in Table 2 and plotted in FIG.

[Table] Example 3 Using two types of polyethylene terephthalate chips with intrinsic viscosities of 0.685 and 0.550, a single-hole discharge rate of 2.4 was produced using the same spinning device as in the case of cotton A in Example 1.
g/min (high and low viscosity each 1.2 g/min), spinning speed 1000 m/min, and spinning temperature 273°C. The obtained undrawn tow was stretched at a drawing speed of 100 m/min, and then at 90°C. By drying and cutting into 51 mm pieces, hollow composite latent crimped cotton (referred to as E-cotton) was obtained. The fineness of this cotton is 6.5 denier, and the heat shrinkage rate is
It was 13.0%. Next, the obtained E cotton and Desi cotton were mixed in the respective ratios shown in Table 2, and then put into a lap making machine similar to that in Example 1, and formed into a lap with a basis weight of 2.4 kg/m ² . Heat treatment was performed in the same manner as in Example 1, and the texture of each lap after heat treatment was observed. The static pressure difference during heat treatment corresponding to each lap and the texture observation results after treatment are shown in Table 3.
It is plotted in the figure.

[Table] Example 4 Using two types of chips of high viscosity and low viscosity polyethylene terephthalate with intrinsic viscosities of 0.685 and 0.485, single hole discharge amount was measured using a spinning machine for manufacturing composite fibers.
3.0g/min (1.5g/min each for high and low viscosity)
After spinning at a spinning speed of 800 m/min and a spinning temperature of 275°C, the resulting undrawn tow was drawn at a drawing speed of 100 m/min, dried at 70°C, and cut to 75 mm, resulting in a heat-shrinkable fineness of 10.2 denier. Cotton with a percentage of 19.1% (referred to as F cotton) was obtained. Next, the obtained F cotton and the D cotton obtained in Example 2
A mixture of cotton in the proportions shown in Table 4 was heat treated in the same manner as in Example 1, and the texture was observed. The results are shown in Table 4 and plotted in FIG.

【table】 [Brief explanation of the drawing]

Figure 1 is a graph showing the relationship between the specific volume at initial load and bulk reduction rate of padding cotton for comforters, and Figure 2 is a graph showing the relationship between crimping of 6d x 75mm polyester composite hollow cotton for comforters. Figure 3 is a graph showing the relationship between the number and the specific volume at the time of initial load, and illustrates the suitability range for a futon according to the mixing ratio and static pressure difference of the high shrinkage cotton according to the present invention. , each point represents the characteristic value of the example, and the symbol represents suitability for the purpose of the present invention (○ mark: suitability, × mark: no).

Claims (1)

[Scope of Claims] 1 Polyester fiber cotton having high heat shrinkage or cotton containing 30% or more of the same fiber is wrapped in a wrapping machine for forming futon cotton or on a card and formed into the shape of a futon, followed by hot air circulation heat treatment. In a method for producing padded cotton for futons made of polyester fibers, which is subjected to a certain high temperature treatment in a machine, the static pressure difference P (mmAg) generated by the cotton layer in the heat treatment zone is calculated by comparing the mixing ratio R of the high shrinkage fibers. Relational expression 12/R-9≦P≦21/R+9 (however, 0.3≦R
≦1) A method for manufacturing polyester fiber padding for futons, which is characterized by adjusting the content within a satisfying range.