US1807571A - A trust of massa - Google Patents

Description

Patented May 26, 1931 UNITED, STATES PATENT OFFICE MASSACHUSETTS, ASSIGNOR TO LUDELOW LOW, MASSACHUSETTS, A TRUST OF MASSA- LINEN SHOE THREAD Ho Drawing.

This invention relates to an improved linen shoe thread intended and adapted for the sewing of shoes.

The new linen shoe thread of the present invention is a linen thread specially treated to preserve it against the deteriorating conditions to which it is subjected when used in shoes. More particularly, the invention relates to an unboiled linen thread with its normal content of pectin, hemi-cellulose and other non-cellulose constituents, which is preserved so that it is adapted for use, for example, as a welt thread as a substitute for the boiled linen thread or cheaper cotton thread now commonly employed for shoe manufacture.

In shoe manufacture the uppers are sewed to the welts by shoe thread which is usually linen thread for the better grades of shoes and cotton thread for the cheaper grades of shoes. Similarly, in sewing the outer edges of the soles of shoes linen thread is used for the better grades of shoes and cotton thread for the cheaper grades.

The linen thread which is commonly used for shoe thread is a so-called boiled thread, made by boiling the yarn from which the thread is made, in a dilute solution of caustic soda and soda ash which dissolves out the greater part of the pectin, hemi-cellulose and non-cellulose constituents, giving what is known in the trade as a boiled yarn, from which linen shoe thread is now made. In this way the flax is freed more or less completely from the non-cellulose constituents which readily undergo deterioration or decomposition by micro-organisms; and it has heretofore been considered necessary to remove such constituents more or less completely in order to produce a satisfactory linen shoe thread.

The shoe thread of shoes is subjected to conditions which favor and promote deterioration or decomposition of the shoe thread, and particularly of shoe thread which contains any substantial amount of readily decomposable constituents which are decomposed by mold or bacterial action. Shoes in the ordinary course of wear come intocon tact with street dirt, dust, mud, etc., and it is well known that ordinary street dirt and Application filed September 29, 1930. Serial No. 485,328.

dust, etc., are contaminated with or contain numerous micro-organisms, such as molds, bacteria, etc. In rainy weather shoes come in contact with wet sidewalks and streets or with wet dirt or mud and the water penetrates the'shoe to a greater or less extent, carrying with it contaminating micro-organisms. Leather shoes are also kept more or less moist byperspiration, particularly in the summer time and in humid weather. When shoes become wet or moist either through rainy weather or through perspiration with improper opportunity for drying out, the conditions are favorable for the rapid growth and development of molds and bacteria which are present in shoes which have been Worn for any length of time. When shoes are worn day after day and particularly in rainy weather or in hot, humid weather and are not permitted to dry out properly favorable conditions are presented for development and growth of destructive micro-organisms. Even boiled linen thread and cotton thread are not immune from such micro-organisms.

I have investigated the action of microorganislns from street dirt on unboiled linen shoe thread and I have found that under favorable conditions of moisture and temperature such threads undergoes rapid deterioration. I have found, however, that by incorporating in the unboiled linen thread a suitable disinfectant the thread can be preserved and made resistant to such micro-organisms and can thereby be made available for use as a valuable substitute for boiled linen shoe thread and for cotton shoe thread. I have also found that even the boiled linen thread can be improved in its resistance to deterioration by similarly incorporating a suitable disinfectant therein.

The disinfectants which I employ in the treatment of the shoe thread are disinfectants which are of a more or less permanent character and which remain in the shoe thread and impart to it. resistance to decomposition or deterioration by such destructive micro-organisms as are found in street dirt,

mud and the like with which shoes are continually brought in contact in every day use. The dlsinfectant may kill or destroy the moulds, bacteria or micro-organisms by reason of its toxic poisoning action, or the disinfectant may produce a state of suspended growth by reason of a toxic poisoning action less drastic than that required to kill or destroy the organisms; or the disinfectant may kill or destroy the moulds, bacteria or micro-organisms or produce a state of suspended growth by reason of its dehydrating action on the material treated or on the organisms themselves. Certain disinfectants may exhibit a combined poisoning and dehydrating action. Merely boiling the thread without alkali, whereby the thread is subjected to a sterilization by heat alone, is not sufficient to preserve the thread against attack by micro-organisms normally accompanying unboiled thread, or to be found in street dirt or the like.

The disinfectant which I have f und particularly advantageous and effectiv is a dyestuff known in the trade as Brilliant Green, which belongs to the triphenyl methane series of coloring matters and is chemically designated as the sulfate or double zinc chloride of tetra ethyl diamido-triphenyl-carbinol. Other dyestuffs which have a disinfecting and preservative action can be used, including other dyestuffs of the triphenyl methane series which havesuch a disinfecting and preservative action. Othersubstances than dyestuffs can also be used as disinfectants or preservatives, including sodium silico fluoride, sodium phenyl phenate and certain copper salts which have a disinfect ing and preservative action.

The incorporation of the disinfectant with the thread can take place at different stages of manufacture. It may be incorporated, for example, during the spinning of the yarn by using what is known as the damp spinning process and moistening the yarn with a solution of the disinfectant. The thread can also be dipped in a solution of the disinfectant after it has been formed. The method of incorporation which I consider particularly advantageous is by passing the yarn through a bath of the disinfectant as the plies or strands of yarn are drawn through the twisting machine tomake the finished thread. The yarns are commonly passed through a water bath to wet them for this twisting operation and the incoporation of the disinfectant in the water bath enables the thread tobe manufactured in the ordinary manner without any additional operations but nevertheless with satisfactory incorporation of the disinfectant in the yarn and thread. In such case only the usual drying of the thread is needed to complete its manufacture.

The amount of disinfectant which is incorporated in the thread will vary with different disinfectants and may vary with the same disinfectant. In the case of Brilliant Green incorporation of as little as one part of the dye in ten thousand parts of the thread by weight is effective in retarding mold and bacterial growth, but larger amounts can be used, particularly for tropical climates or other places where the shoes are subjected to unusually severe conditions promoting deterioration or decomposition of the linen thread. In some cases as much as 1% or more of antiseptic may be incorporated in the thread although ordinarily a much smaller amount will be suificient.

The improved unboiled linen shoe thread of the present invention has important advantages in its method of manufacture as compared with the ordinary boiled linen thread which is now used. The boiling operation which requires special equipment and chemicals and requires a considerable period of time for the boiling operation'can be eliminated thereby economizing in cost of equipment, in cost of chemicals, in the time required for making the thread, and in the labor and expense involved in its manufacture. While the boiling operation removes up to 20% or more of the weight of the flax, the entire weight of the flax is retained in the new unboiled thread which is nevertheless of a strength comparable with that of boiled thread, thereby in effect very materially increasing the amount of thread which can be manufactured from the same amount of flax. That part of the flax which it has heretofore been considered necessary to remove in the boiling operation and which, unless removed, causes the thread as a whole to undergo rapid deterioration is so preserved by the incorporation of the disinfectant in the thread, according to the resent invention, that it remains as a valua le part of the thread, making the thread as a whole comparable in strength and usefulness with boiled thread of equal weight which would require a considerably greater amount of flax for its manufacture.

Inasmuch as the disinfectant or preservative can readily be incorporated in the thread as a part of its process of manufacture without adding to the cost of manufacture except for the small cost of. the antiseptic or preservative, the improved unboiled shoe thread can be manufactured at a materially less expense than the ordinary boiled shoe thread, thus enabling an increased yield of shoe thread to be produced from the same amount of flax and at less cost of manufacture.

I have found that even boiled linen shoe thread can be improved in its resistance to deterioration by similarly incorporating a I disinfectant or preservative in it, thereby gi v ing an improved boiled linen shoe thread; but in the case of such a boiled shoe thread the cost of manufacture is increased by the boiling operation and the amount of shoe thread produced from the flax is correspondingly 'thread will retain longer life to the shoe,

decreased as compared with the improved unboiled shoe thread above described. While therefore the invention in its broader aspects includes an improved boiled shoe thread, the unboiledlinen shoe threadof the present invention has many advantages, bein distinguished from boiled shoe threads iy its content of all of the normal constituents of the flax fiber as well as by the presence of the preservative or disinfectant, by the greater yield of shoe thread produced from the same amount of flax fiber, by its materially decreased cost of manufacture, and in other respects such as those above referred to.

The advantages which the improved shoe thread of the present invention presents will be obtained when the shoe thread is used in the manufacture of shoes and when the shoes are then worn and subjected to the varying conditions of use where theyv come into contact with street dirt, dust, mud, etc. and become infected with various micro-organisms, and when conditions of moisture and temperature are favorable for the growth of such micro-organisms. Thus, even where the shoes remain moist and warm for considerable periods of time, as in rainy or humid weather, or where proper opportunity is notprovided for drying out the shoes, the objectionable deterioration of the shoe thread which would otherwise take place is prevented or retarded or minimized, thereby insuring that the shoe its strength and giving particularly under unfavorable conditions of use. The welt thread, which is employed for sewing the uppers of the shoe to the welt and which is close to the foot of the wearer so that it is kept Warm and, in warm or humid weather, is keptmoist by perspiration is nevertheless preserved against objectionable deterioration by micro-organisms which gainaccess'to it and which would otherwise cause more rapid deterioration of the shoe thread. Similarly the shoe threads used for sewing the outer edge of the soles of the shoe and which are commonly exposed to the atmosphere and to dust, dirt, mud, etc. both on the top and the bottom of-the sole are preserved against deterioration such as would otherwise tend to occur more rapidly. Thus, even the unboiled shoe thread, when subjected to such adverse conditions in. the shoe, is comparable with or may even be superior to the ordinary boiled shoe thread; While the boiled shoe thread which is preserved in accordance with the present invention will be materially improved in its resistance to such deterioration. The present invention accordingly makes it'5possible to insure that high grade'shoes made of high grade leather can be sewed together with the improved shoe thread tion, thereby insuring the maximum life and utility of the shoe as a whole.

The shoes sewed with the new linen shoe of the present inventhread are not claimed herein but are claimed in m divisional application, Serial N o. 530,- 154 ed April 14, 1931.

I claim:

-1. A linen shoe thread having a small amount of a poisoning or dehydrating disinfectant incorporated therein to preserve the shoe vthread against objectionable deterioration by micro-organisms in street dirt and the like.

2. An unboiled linen shoe thread containing the normal non-cellulose constituents of the flax fiber and having a small amount of a poisoning or dehydrating disinfectant incorporated therein to preserve the shoe thread against objectionable deterioration by micro-organisms in street dirt and the like.

3. A linen shoe thread having a small amount of a triphenyl methane dye incorporated therein to preserve the shoe thread against objectionable deterioration by micro-organisms in street dirt and the like.

4. A linen shoe thread having a small amount of Brillant Green dye incorporated therein to preserve the shoe thread against objectionable deteriorationby micro-organisms in street dirt and the like.

5. An unboiled linen shoe thread containing the normal non-cellulose constituents of flax fiber andhaving a small amount, of

ture; 2 r

WALTER W. EVANS.