Patent Application
20130167858
The invention relates to a hair extension and process for the same, especially to a hair extension and process for the same, which enables users to have hairstyles of excellent hair quality, affluent hair, or long hair by extending hairs of the user.
Conventional hair extension is made by connecting one ends of flatly-arranged extension hairs into one by sewing, which was to attach to the user's hairs with hair clip or regular hair pin.
In such conventional hair extension, since the extension hairs were detached from part fixed by sewing or entangled, it was not able to be used repeatedly.
Also, since such conventional hair extension is unable to keep in place in an attached state to the user's hairs, it must be treated often.
Additionally, since such conventional hair extension was thick and had extension hairs divided and tied in sewing threads by a few strands by strands, there were many bumps on the surfaces. Therefore, such conventional hair extension had rough surfaces.
Since such conventional hair extension was hard to attach to the user's hairs and connected tightly to the user's hairs, the user had problems to move head freely.
The object of the invention is to provide a hair extension, in which extension hairs are not detached or entangled since they are fixed strongly.
Another object of the invention is to provide a hair extension, in which density or total number of extension hairs in a direction of thickness can be controlled easily in the process for manufacturing the hair extension.
Still another object of the invention is to provide a hair extension, which keeps initial state of being attached to user's hairs for a long time.
Still another object of the invention is to provide a hair extension, in which since it is possible to attach to the user's hairs with some movability it is easy to move after being attached and it keeps the attached state for a long time.
Still another object of the invention is to provide a hair extension, which can be used repeatedly many times.
Still another object of the invention is to provide a hair extension, which has smooth surfaces compared to conventional ones.
Still another object of the invention is to provide a hair extension, which is easy to attach to the user's hairs.
Still another object of the invention is to provide a process for manufacturing a hair extension according to the invention.
A hair extension according to the invention comprises a extension hair portion including a plurality of strands of extension hairs and a binding portion for tying one ends of the extension hairs into one, wherein the binding portion comprises a sheet binding portion in which two sheets of synthetic resin overlapped with the one ends in-between are molten and glued so as to fix the one ends into one body.
The synthetic resin sheet is preferably a polyurethane sheet.
In cases, the extension hair portion comprises a first sub-extension hair portion and a second sub-extension hair portion disposed in layers together with the first sub-extension hair portion, and the sheet binding portion is formed by melting and gluing with neighboring ones a first polyurethane sheet disposed at an outer side of the first sub-extension hair portion opposite to the second sub-extension hair portion, a second polyurethane sheet disposed between the first and second sub-extension hair portions, and a third polyurethane sheet disposed at an outer side of the second sub-extension hair portion opposite to the first sub-extension hair portion.
In some cases, the extension hair portion comprises a first sub-extension hair portion, a second sub-extension hair portion disposed in layers together with the first sub-extension hair portion, a third sub-extension hair portion disposed in layers on the second sub-extension hair portion opposite to the first sub-extension hair portion, and the sheet binding portion is formed by melting and gluing with neighboring ones a first polyurethane sheet disposed at an outer side of the first sub-extension hair portion opposite to the second sub-extension hair portion, a second polyurethane sheet disposed between the first and second sub-extension hair portions, a third polyurethane sheet disposed between the second and third sub-extension hair portions, and a fourth polyurethane sheet disposed at an outer side of the third sub-extension hair portion opposite to the second sub-extension hair portion.
The synthetic resin is preferably a polyurethane sheet with thickness of 0.06˜1.00 mm.
In the extension hair portion, the extension hairs are preferably disposed in a plane.
In each of the first through third sub-extension hair portions, the extension hairs are disposed in a plane and there are 1 to 5 strands in the direction of thickness.
In the sheet binding portion are preferably formed holes with intervals.
A process for manufacturing a hair extension according to the invention comprises: a first step for disposing two synthetic resin sheets in layers with one ends of a first sub-extension hair portion; and a first step for melt-and-gluing the one ends of the first sub-extension hair portion between the two synthetic resin sheets by melt-and-gluing the two synthetic resin sheets while pressing the two synthetic resin sheets toward each other.
The synthetic resin sheet is a polyurethane sheet, and the process for manufacturing may further comprise: a second step for disposing additional polyurethane sheet on a portion in which a second sub-extension hair portion is stacked in layers on the first sub-extension hair portion and one ends of the second sub-extension hair portion are overlapped on the molten and glued portion of the two polyurethane sheets; and a second step for melt-and-gluing the additional polyurethane sheet by heating while pressing to the molten and glued portion and fixing the second sub-extension hair portion between the additional polyurethane sheet and a portion where the two polyurethane sheets are molten and glued.
Also, the process for manufacturing may further comprise: a third step for disposing a newly added polyurethane sheet on a portion in which a third sub-extension hair portion is stacked in layers on the second sub-extension hair portion and one ends of the third sub-extension hair portion are overlapped on the molten and glued portion of the three polyurethane sheets; and a third step for melt-and-gluing the newly added polyurethane sheet by heating while pressing to the molten and glued portion and fixing the third sub-extension hair portion between the newly added polyurethane sheet and a portion where the three polyurethane sheets are molten and glued.
The thickness of the synthetic resin is preferably 0.06˜1.00 mm.
In each of the first through third sub-extension hair portions, the extension hairs are disposed in a plane and there are 1 to 5 strands in the direction of thickness.
The synthetic resin sheet is polyurethane sheet, and preferably the temperature of the polyurethane sheet in the first step for melt-and-gluing is 150˜160 degrees in Celsius, and the pressure is 30˜50 kg per centimeter squared.
The process may further comprise a step for forming a plurality of holes with intervals where the synthetic resin sheets are molten and glued.
Below, preferable embodiments of the invention are described in detail referring to the figures.
As shown in
The sheet binding portion 130 is formed by melt-and-gluing the band-shaped polyurethane sheets together with the one ends of the extension hairs 112 with ends aligned, that is, the one end of the extension hair portion 110 in between, which fixes the one ends of the extension hairs 112 integrally. For polyurethane sheet may be used a polyurethane solution including 29˜31:10˜20:50˜60 in weight of polyurethane, methyl ethyl ketone (MEK, CAS No. 78-93-3) and dimethylformamide (DMF, CAS No. 68-12-2), which is dried or baked to be 0.06˜0.1 mm thick in an oven and the like. The drying or baking temperature is preferably about 70˜90 degrees, most preferably 80 degrees in Celsius. Of course, instead of such a polyurethane sheet, other synthetic resin sheet may be used.
In a case of melt-and-gluing using polyurethane sheets, polyurethane sheet that is thinner than 0.06 mm is too little to be molten, such that it tends to make melt-and-gluing erroneous and the melt-and-gluing process of the two sheets may be infested with deformation.
And when the thickness of polyurethane sheet is larger than 0.1 mm, it takes longer for heat to be delivered to inside and the temperature of outer surface where the pressing heater touches rises too high, reducing work efficiency.
The thickness of 0.08 mm or 0.09 mm of polyurethane sheet gives minimized erroneous melt-and-gluing, less deformation, and good workability.
That is, for the polyurethane sheet used for manufacturing the hair extension 100 according to the invention, 0.06˜0.1 mm thick ones are good to be used, and 0.08˜0.09 mm thick ones are more preferable.
A preferable dimension (width×length) of polyurethane sheet is 1.2 cm×9 cm. However, for a larger hair extension, a 2 cm×15 cm one may be used. In cases, ones smaller than 1.2 cm×9 cm may be also used.
That is, the size of polyurethane sheet may be changed according to the size of the hair extension 100.
If pressing together and heating the two polyurethane sheets in order to form sheet binding portion 130, the molten portions smears into the extension hairs 112 and encloses one end, and then encounters another molten portions at the other side, to be glued.
If cooling down the molten portions, the portions get solidified and hard. Thus the one end of the extension hair portion 110 is fixed strongly between the two neighboring polyurethane sheets.
As shown, in the sheet binding portion 130 are formed a plurality of holes 130a with intervals. The holes 130a are for attaching the hair extension 100 according to the invention to the user's hairs, the diameter of which may be about 1.5 mm˜2.0 mm, which may be adjusted.
Referring to
Referring to
In
Also, between the second sub-extension hair 110b and the third sub-extension hair 110c is disposed a third polyurethane sheet 133. The third polyurethane sheet 133 and the second polyurethane sheet 132 are melt-and-glued with each other, and fix one end of the second sub-extension hair 110b between the second polyurethane sheet 132 and the third polyurethane sheet 133 to the sheet binding portion 130.
In the outer side of the third sub-extension hair 110c is disposed a fourth polyurethane sheet 134. The fourth polyurethane sheet 134 and the third polyurethane sheet 133 are melt-and-glued with each other, and fix one end of the third sub-extension hair 110c between the third polyurethane sheet 133 and the fourth polyurethane sheet 134 to the sheet binding portion 130.
In the embodiment of
Also, the first polyurethane sheet 131 through the fourth polyurethane sheet 134 are disposed in layers overlapping each of one ends of the first sub-extension hair 110a through the third sub-extension hair 110c between neighboring ones, and neighboring ones are melt-and-glued respectively.
In
The hair extension 100 shown in
Describing in more detail referring to
When density of each sub-extension hairs is same, as shown in
Referring to
It is also possible that in the hair extension 100 according to the invention the extension hair portion 110 comprises more than four layers of sub-extension hairs.
That is, in the hair extension 100 according to the invention, it is easy to adjust the density of the extension hairs 112.
In the manufacturing of the hair extension 100 according to the invention, a fixing plate 150 as shown in
Referring to
Each of extension hairs 112 is attached to the Velcro tape 154 by a thickness of 1-5 strands, preferably 2-4 strands. As the number of the extension hairs 112 disposed in a direction of thickness increases, the density of sub-extension hairs increases, but because the molten portion of polyurethane sheet is too thick to smear into the thick extension hairs 112, the glued area is reduced, both of the polyurethane sheets are hard to melt-and-glue to each other, and the fixing force of each extension hair 112 is lowered, so as to make defect rate increase.
In order to manufacture a hair extension 100 having three layers of the first sub-extension hair 110a through the third sub-extension hair 110c as shown in
That is, those shown in
Next, as shown in
And then, as shown in
It is preferable for the first polyurethane sheet 131 and the second polyurethane sheet 132 to be overlapped completely on top of each other, but in order to show the top and bottom sheets in the figure, the edges of the two sheets were shown misaligned. This holds true for the third polyurethane sheet 133 and the fourth polyurethane sheet 134 below.
In this state, as shown in
The molten portions of the first polyurethane sheet 131 and the second polyurethane sheet 132 molten by heating smear into the extension hairs 112 between the two sheets under pressure by pressing together, are melt-and-glued together, and also enclose the one ends of the extension hairs 112 and fix the extension hairs 112.
If stopping heating and pressing the two sheets through the pressing heater 164 by lifting up the pressing heater 164, the molten portion of the two sheets are cooled down and coagulated. Thus the two sheets keep the solidly melt-and-glued state, and fix the extension hairs 112.
By the above, the sheet binding portion 130 which fixes one end of the first sub-extension hair 110a first to between the two sheets using melt-and-gluing is formed on the one end of the first sub-extension hair 110a (S4). In this case, the extension hair portion 110 comprises the first sub-extension hair 110a only. After the first melt-and-gluing step is done, the fixing plate 150 is detached from the first sub-extension hair 110a.
Here the heating temperature of the first and second polyurethane sheets 131,132 is about 150˜160 degrees in Celsius, the pressure about 30˜50 kg/cm2, and the pressing time about 50˜70 sec.
The thickness and dimension of polyurethane sheet have been discussed above already. Instead of polyurethane sheet other types of synthetic resin sheets can be used, which has preferably relatively low melting temperature of 140˜200 degrees in Celsius, good gluing power, and little deformation in cooling down.
After the sheet binding portion 130 is formed by melt-and-gluing the two sheets, as shown in
And, on one end of the second sub-extension hair 110b is disposed additional third polyurethane sheet 133, and the third polyurethane sheet 133 is heated and pressed toward the sheet binding portion 130 with the pressing heater 164, melt-and-gluing for a second time. Thus, one end of the second sub-extension hair 110b is fixed between the additionally added third polyurethane sheet 133 and the sheet binding portion 130 formed by the two melt-and-glued polyurethane sheets (S5).
After the third polyurethane sheet 133 is melt-and-glued, the sheet binding portion 130 becomes a sheet binding portion 130 by three sheets. In such a case, the extension hair portion 110 comprises the first sub-extension hair 110a and the second sub-extension hair 110b overlapped with the first sub-extension hair 110a.
After the second melt-and-gluing step is done, the fixing plate 150 is detached from the second sub-extension hair 110b.
Then, as shown in
And, by moving the pressing heater 164 downward, the fourth polyurethane sheet 134 is pressed down toward the sheet binding portion 130 to which three sheets are melt-and-glued and heated for a third melt-and-gluing. Thus the one end of the third sub-extension hair 110c is fixed solidly between the new fourth polyurethane sheet 134 and the portion where the three sheets are melt-and-glued (S6). By this, the third sub-extension hair 110c is also fixed to the sheet binding portion 130.
Thus, the hair extension 100 according to the embodiment includes the sheet binding portion 130 by four sheets each fixing the one ends of the first sub-extension hair 110a through the third sub-extension hair 110c inserted between the neighboring melt-and-glued portions while the four sheets are overlapped.
After finishing the sheet binding portion 130, if the edges of the sheet binding portion 130 are not aligned top to bottom, the edges of all the polyurethane sheets get aligned by cutting the edges.
The first sub-extension hair 110a through the third sub-extension hair 110c are preferably formed with a same width.
If the third melt-and-gluing step is done, the fixing plate 150 is detached from the third sub-extension hair 110c.
Then, as shown in
After boring the holes 130a, the remaining debris or other material sticking around or to the edge of sheets are removed for finishing.
By doing as in the above, the hair extension 100 according to the invention is manufactured, which includes the extension hair portion 110 in which the sub-extension hairs are disposed in three layers.
In cases, for the synthetic resin sheet 130b such as polyurethane sheets for forming the sheet binding portion, instead of the two sheets used in the previous embodiment, can be used a sheet which is foldable as in
Referring to
Check the position where to attach the hair extension 100 in the user's head 10, and taking out the user's hairs 12 which are in positions corresponding to each holes 130a through the holes 130a using a hooking device 170 having a hook at an end as shown in
Then, pass the hairs 12 taken-out through the holes 130a through an engaging ring 180 as in
After that, as shown in
In order to detach the hair extension 100 according to the invention after using them attached to the user's hairs 12 as in
And according to thermal analysis of human hairs, the rare elements and protein in hairs begin to burn at 200 degrees in Celsius, and if heating them up slowly (temperature increasing rate: about 5 degrees/min in Celsius from room temperature to 500 degrees in Celsius at which most of hair protein gets carbonized, the total weight of hairs gets reduced by 75% of the initial weight.
Considering the above, for the synthetic resin sheets applied to the invention is suitable the polyurethane sheet as described above, but one person skilled in the art belonging to the invention may recognize to use other synthetic resin if they are melt-and-glued together below 200 degrees in Celsius, since they do not give a large thermal damage to extension hairs.
The hair extension according to the invention enables to fix extension hairs to a synthetic resin sheet such as thin and light polyurethane sheet in a high density.
The hair extension according to the invention has the extension hairs spread out widely in layer, but since it has a sheet binding portion that can form holes, it can be attached to and detached from the user's hairs rapidly and easily using the engaging rings.
The hair extension according to the invention enables the user to move freely because the degree of fixing to the user's hairs can be adjusted and it is fixed to the user's hairs indirectly.
The hair extension according to the invention has extension hairs that is rarely tangled or fallen off and therefore may be used many times, because the extension hairs are attached solidly by melt-and-gluing to resin sheets such as polyurethane sheet.
The hair extension according to the invention may be made with the density of extension hairs adjusted variously according to the usage.
The hair extension according to the invention does not produce rough surfaces since the extension hairs do not have to be tied as in sewing.
The hair extension according to the invention may be used for having hairstyles of excellent hair quality, affluent hair, or long hair by extending hairs of the user.
The process for manufacturing hair extension according to the invention may be used for producing hair extension of good quality to be used repeatedly.
