Claims:

1. A molten metal protective fabric comprising about 30% to 50% by weight of total fabric weight of wool; from about 30% to about 50% by weight of total fabric weight of flame retardant cellulosic fibre; from about 5% to 20% of flame retardant liquid crystal polymer; from about 3% to about 15% by weight of total fabric weight of Polyamide fibre & about 0% to 5% of Antistatic fibre.

2. The yarn of fabric as claimed in claim 1, has a count range from 12Ne to 40Ne (double yarn).

3. The fabric as claimed in claim 1, wherein the flame retardant liquid crystal polymer is aramid flame retardant cellulosic fibre is FR Viscose and the polyamide fibre is a Nylon 66.

4. The fabric as claimed in claim 1, wherein the fabric comprises a woven structure of Twill or Satin weave with or without a grid of antistatic filament at a grid spacing of 5 mm.

5. The fabric as claimed in claim 1, wherein the fabric is a flame retardant fabric.

6. The fabric as claimed in claim 1, wherein the fabric is breathable having MVTR (Moisture Vapour Transmission Rate) as per ASTM E-96-05 more than 1000 gm/M2/Day.

7. The fabric as claimed in claim 1 complies with standards such as EN 1149-5.

8. The fabric as claimed in claim 1, wherein the fabric as per ISO 11612 has achieved D3 and E3 in the weight range of 320 to 450 gsm.

9. A process for manufacturing the molten metal protective fabric as claimed in claim 1, comprising the steps of:

- Spinning the fibres consisting of Flame retardant cellulosic fibre from about 70% to about 90% w/w, polyamide from about 5% to 20% w/w, aramid from about 5% to 15% w/w with or without antistatic fibre from about 1% to 5% wherein the yarn count varied from about 12s Ne to about 40s Ne (double yarn),

- 100% wool yarn is obtained from a worsted spinning system.

- the yarns of two fibers are wound and twisted in doubling machine;

- weaving the yarns interlaced together in textile weave and obtained a woven fabric with twill weave or satin weave with or without a grid of antistatic filament at a grid spacing of 5 mm;

- washing the fabric with hot water to remove impurities;

- dyeing the fabric with low affinity reactive dye with dye fixing to provide the fabric excellent fastness properties;

- optionally the fabric is dyed with acid dye for wool and polyamide part;

- treating the fabric with hydrophilic softener or optionally, treating the fabric with anti-microbial, water and oil repellents, and stain release agents;
, Description:FORM 2
THE PATENTS ACT,
1970 (39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
[See section 10, Rule 13]
MOLTEN METAL PROTECTIVE FABRIC AND GARMENT THEREFROM ;

ARVIND LIMITED, A COMPANY INCORPORATED UNDER THE COMPANIES ACT, 1956, WHOSE ADDRESS IS NARODA ROAD, AHMEDABAD - 382345, GUJARAT, INDIA

THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED.
Field of Invention
The present invention relates to molten metal protective wear fabric. More particularly, present invention relates to the method of making molten metal protective fabric.

Background of Invention
Ferrous and Non-ferrous metals are classified based on the iron content and can be made alloys by addition of other elements into said metal. The wide varieties of alloys have different physical and chemical behaviour.

The flame retardant fabrics are available which can protect against metal. Iron and their alloys derived as steel, stainless steel etc. has a melting temperature above 1200°C and splashing of these metals into the garment and/or protective fabrics, causes a rapid increase in temperature of the garment and causes immediate destruction of the fabric and ultimately to the skin of the wearer due to the break open of the fabric.

The metals such as copper, zinc, lead, tin, aluminium, nickel, or magnesium, with the exception of copper, these metals tend to stick easily in non-protective fabrics. The working temperatures are lower than Iron and the cooling capacity is very high. All these facts, cause that molten metal splash sticks in the fabric and allow immediate heat transfer to the operator himself as well as the fabric destruction. It is therefore essential to choose fibres capable of repelling most of the adhesion of these metals in the fabric.

It is well known that Aluminium is the main non-ferrous alloy and is mostly used in the foundries, and is taken as one of the most critical for its “staying stuck” easy behaviour in the clothes of the smelters. Molten aluminium (secondary production process) has an operating temperature of 700/800°C, and is enough to cause severe burns too. In both the production processes, i.e. primary and secondary smelting, the Aluminium is the metal alloy that poses more danger when smelters and foundry men meet their liquid splashing. Alloys such as tin, zinc or lead, which almost always remain adhered to the fabric and in these cases, seek the maximum repellence while it is true that the temperatures of these metals are lower than the Aluminium primary production.

Ferrous metals have a high destructive power on the protective clothing while nonferrous metals tend to stick causing a dangerous damage. The protective fabrics for ferrous metals such as iron or steel, must withstand high thermal shock splashes of these metals, to avoid being destroyed by this effect and maintain its structure so as to prevent metal from entering into the ‘wearer’ clothing. The use of flame retardant clothing, always working together to minimize the damage if the outer layers of tissue, may come to fail.

Woven fabrics for protection nonferrous metals mainly aluminium, must allow full and absolute repellence to these; and when sticks to the fabric is when the damage they cause are very high. These types of protective fabrics are the most technical one in this sector and it is very important to select the appropriate one.

Currently Wool/ Fire Retardant Viscose fabrics are used for molten aluminium protection and tested as per ISO 11612 “D” Code. Due to the sticky behaviour of molten aluminium than molten iron many inherently flame retardant fabric fail in “D” code but Pass “E” code though the temperature is less in case of molten aluminium around 816 0C whereas molten iron is 1594°C.

Due to this wool/FR viscose blended fabric is used for molten aluminium protection. This yarn is produced by a worsted spinning system and fabric made from this yarn is not comfortable to be and give itch due to wool fibres. The garment made from this fabric has a problem of shrinkage, pilling and not having an appealing look.

Also, these kind of fabrics can generate static charges when a person wears them and is doing dynamic activities can dissipate static electricity and thus be safe for environments which could generate static charges and hence cause sparks.

Thus, there is a need for fabric that can overcome the limitations of existing protective fabrics and can dissipate static electricity and thus be safe for environments which could generate static charges and cause sparks.

Object of the Invention:
The primary object of the present invention is to provide molten metal protective fabrics.

Further object of the present invention is to provide molten metal protective fabrics which are soft and comfortable.

Yet another object of the present invention is to provide molten metal protective fabrics which do not shrink, pill and have an appealing look.

Yet another object of the present invention is to provide molten metal protective fabrics which can dissipate static electricity and thus be safe for environments which could generate static charges and cause sparks.

Yet another object of the present invention is to provide garments prepared from the molten metal protective fabrics.

Summary of the Invention:
In order to achieve the afore-said objectives, the present invention provides a molten metal protective fabric.

A According to one aspect, provided herein is a molten metal protective fabric of the present invention comprising from about 30% to about 50% w/w of wool; from about 30% to about 50% w/w of flame retardant cellulosic fibre; 5% to 20% of a fire retardant Liquid crystal polymer, from about 3% to about 10% w/w of Polyamide fibre and 0% to 5% of Antistatic fibres

The molten metal protective fabric according to the invention comprises a woven structure of Twill or Satin weave.

The fabric is a flame retardant fabric as it comprises the flame retardant cellulosic fibre preferably FR Viscose and the Liquid Crystal Polymer is preferably an aramid.

The fabric is breathable having MVTR (Moisture Vapour Transmission Rate) as per ASTM E-96-05 more than 1000 gm/M2/Day and achieves D3 and E3 in the weight range of 320 to 450 gsm and also passes EN 1149-5.

According to another aspect, provided herein is a process for manufacturing the molten metal protective fabric, comprising the steps of:

- spinning the fibres consisting of Flame retardant cellulosic fibre from about 70% to about 90% w/w, polyamide from about 5% to 20% w/w, aramid from about 5% to 15% w/w and antistatic fibre from about 0% to 5% wherein the yarn count varied from about 12s Ne to about 40s Ne (double yarn),
- Wool fibres were run on a worsted spinning machine to obtain 100% wool yarn ;
- The yarns of two fibers are wound and twisted in doubling machine;
- weaving the yarns interlaced together in textile weave and obtained a woven fabric with twill weave or satin weave with or without a grid of antistatic filament at a grid spacing of 5 mm ;
- washing the fabric with hot water to remove impurities;
- dyeing the fabric with low affinity reactive dye with dye fixing to provide the fabric excellent fastness properties;
- optionally the dyed flame retardant cellulosic fibre is dyed with acid dye for wool and polyamide part;
- treating the fabric with hydrophilic softener;
- optionally, treating the fabric with antimicrobial, water and oil repellents, and stain release agents;
- allowing the fabric to shrink in length as well as width, to provide a permanent dimension to obtain the ready to use fabric.

Detailed Description of Invention:
The following description is provided to assist in a comprehensive understanding of exemplary embodiment of the invention. It includes various specific details to assist the understanding but these are to be regarded as merely exemplary.

Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope of the invention. In addition, description of well-known functions / constructions is omitted for clarity and consciousness.

The terms and words used in the following description and claim are not limited to the bibliographical meanings, but are merely used by the inventor to enable a clear and consistent understanding of the invention. Accordingly, it should be apparent to those skilled in the art that the following description of exemplary embodiments of the present invention are provided for illustration purpose and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.

It is to be understood that the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise.

Features that are described and/or illustrated with respect to one embodiment may be used in the same way or in a similar way or more other embodiment and/or in combination with or instead of the features of other embodiments.

It should be emphasized that the term “comprises/comprising” when used in this specification is taken to specify the preference of stated features, integers, steps or components but does not preclude the presence or addition of one or more other features, integers, steps or components or groups thereof.

Those skilled in the art will be aware that the invention described herein is subject to variations and modifications, other than those specifically described. It is to be understood that the invention described herein includes all such variations and modifications. The invention also includes all such steps, features, compositions and compounds referred to or indicated in these specifications, individually or collectively, and any and all combinations of any two or more of said steps or features.

The present invention is not to be limited in scope by the specific embodiments described herein, which is intended for the purposes of exemplification only. Functionally-equivalent products, compositions, and methods are clearly within the scope of the invention, as described herein.

The present invention provides molten metal protective fabric with wool, FR cellulosic fibre, FR liquid crystal polymer, polyamide & antistatic fibres or filaments.

According to one aspect, provided herein is a molten metal protective fabric comprising From about 30% to about 50% by weight of total fabric weight of wool including all the original and derived varieties of cashmere, merino, angora etc in the super washable form that is the wools shall not felt after machine wash; From about 30% to about 50% by weight of total fabric weight of flame retardant cellulosic fibre such as FR Viscose; From about 5% to 20% of aramid comprising both meta and para aramid and their derivative products classified in the range of Liquid crystal polymers; From about 3% to about 15% by weight of total fabric weight of Polyamide fibre & about 0% to 5% of Antistatic fibre.

According to an embodiment, the fabric comprises a woven structure of Twill or Satin weave with or without a grid of antistatic filament at a grid spacing of 5 mm.

According to another embodiment, the fabric is a flame retardant fabric. Because the fabric comprises flame retardant fibre, the fabric is flame resistant substantially through the life of the garment made from the fabric.

According to another embodiment, the fabric is breathable (air permeable, moisture vapour permeable) which helps reduce perspiration and provides greater comfort to the user for longer periods of time. The MVTR (Moisture Vapour Transmission Rate) as per ASTM E-96-05 is more than 1000 gm/M2/Day.

According to another embodiment, the metal protective-wear is typically used when there is a risk of molten metal such as iron/ aluminium or cryolite in the working area and tested as per ISO 11612, in which sub category as ISO 9185 where Code “D” for aluminium and Code “E” for iron. The fabric according to the invention D3 and E3 in the weight range of 320 to 450 gsm.

Performance Standard: ISO 11612: 2015, Clause 7.5 Molten iron splash ISO 9185: 2007,
Metal: Iron (>97% purity), Pouring Temperature: 1400 ± 20°C
Pouring Height: 225mm, Specimen angle to the horizontal: 75°

Property ISO 11612 Requirements
7.5 Molten iron
splash
(Code letter E) Level Fe
E1 = 60g
E2 = 120g
E3 = 200g

Performance Standard: ISO 11612: 2015, Clause 7.4 Molten aluminium Splash,
Test Method: ISO 9185: 2007, Metal: Aluminium, Pouring Temperature: 780 ± 20°C
Pouring Height: 225mm, Specimen angle to the horizontal: 60°

Property ISO 11612 Requirements
7.4 Molten aluminium
splash
(Code letter D) Level Al
D1 = 100g
D2 = 200g
D3 = 350g

The fabrics described herein are dimensionally stable (i.e., display reduced stretching or shrinking), and optionally further comprise other functional durable finishes such as an anti-microbial, water and oil repellent, stain release Finishes and the like, without affecting protective performance.

The protective wear described herein complies with standards such as ISO 11611 A1, ISO 11612 (Code “D”, Code “E”), ISO 15025-A1

The protective wear described herein complies with standards such as EN 1149-5.

According to another aspect, provided herein is a process for manufacturing the molten metal protective fabric, comprising the steps of:

- Spinning the fibres consisting of Flame retardant cellulosic fibre from about 70% to about 90% w/w, polyamide from about 5% to 20% w/w, aramid from about 5% to 15% w/w & antistatic fibre from about 0% to 5% wherein the yarn count varied from about 12s Ne to about 40s Ne (double yarn),

- Wool fibres were run on a worsted spinning machine to obtain 100% wool yarn ;

- The yarns of two fibers are wound and twisted in doubling machine;

- weaving the yarns interlaced together in textile weave and obtained a woven fabric with twill weave or satin weave with or without a grid of antistatic filament at a grid spacing of 5 mm;

- washing the fabric with hot water to remove impurities;

- dyeing the fabric with low affinity reactive dye with dye fixing to provide the fabric excellent fastness properties;

- optionally the dyed flame retardant cellulosic fibre is dyed with acid dye for wool and polyamide part;

- treating the fabric with hydrophilic softener;

- optionally, treating the fabric with anti-microbial, water and oil repellents, and stain release agents;

- allowing the fabric to shrink in length as well as width, to provide a permanent dimension to obtain the ready to use fabric.

The present invention will now be explained with the help of the following examples, however; the scope of the invention should not be limited to said example. It is to be understood that the above described embodiments are merely illustrative principles of the present invention and that many variations may be devised by those skilled in the art without departing from the scope of the present invention. It is therefore intended that such variations be included with the scope of the claims.

EXAMPLES

The Process Flow Chart is a follows:
Spinning ---- weaving ---- wet processing ---- garmenting

Spinning:
Spinning is a process of converting fibres into yarn. Different types of fibre blends/ polymer blends are selected in the spinning process according to the end use requirements for the yarn.

According to one example, Spinning the fibres consisting of Flame retardant cellulosic fibre from about 70% to about 90% w/w, polyamide from about 5% to 20% w/w, aramid from about 5% to 15% w/w & antistatic fibre from about 0% to 5% wherein the yarn count varied from about 12s Ne to about 40s Ne (double yarn), The spinning is conducted in a ring spinning system.
100% wool yarn is obtained from a worsted spinning system.
Then both yarns are wound and twisted in a doubling machine (TFO)
Double yarn gives good lustre and strength while having the same resultant count of single yarn.

In the weaving process, yarns are interlaced together in textile weave and obtained fabric. In the present invention, fabric is woven with twill weave or satin weave with or without a grid of antistatic filament at a grid spacing of 5 mm.

Wet Processing:
Washing – Dyeing – Finishing – Sanforising

Washing: The fabric is washed with hot water to remove impurities.

Dyeing: the fabric is dyed with low affinity reactive dye with dye fixing to make the fabric with excellent fastness properties or if dyed flame retardant cellulosic fibre is used then the fabric is dyed with acid dyed for wool and polyamide part.

Finishing: Fabric is given a soft hand feel by hydrophilic softener.
Other durable features like anti-microbial finish, water and oil repellents, and stain release agents are incorporated at this stage of the process.

Sanforising: The fabric is allowed to shrink in length as well as width, to provide a permanent dimension.

Garmenting: After sanforising the fabric, it is now ready for garment making with flame retardant trims.

Due to the doubling process and wet processing after making fabric the feel, touch enhanced with the molten metal protection properties in addition to this the itching effect also solved. Limited colour can be dyed with excellent fastness properties and the durability and resistance to pilling also enhance exponentially.

Although the invention has been described with reference to specific embodiments, this description is not meant to be construed in a limiting sense. Various modifications of the disclosed embodiments, as well as alternative embodiments of the invention, will become apparent to persons skilled in the art upon reference to the description of the invention. It is therefore contemplated that such modifications can be made without departing from the spirit or scope of the present invention as defined.

The fabric made by the above mentioned steps is summarised in the below examples:

EXAMPLE 1:

Weave: 4/1 Satin
Yarn count: 2/26 Ne
Fabric Composition: Wool 46% + FR Viscose 42% + Polyamide 7% + Para Aramid 5%

The said fabric undergone pre-treatment and washing with hot water to remove impurities, dyeing the fabric with low affinity reactive dye with dye fixing to provide the fabric excellent fastness properties, the fabric is dyed with acid dye for wool and polyamide part, treating the fabric with hydrophilic softener or optionally, treating the fabric with anti-microbial, water and oil repellents, and stain release agents;

EXAMPLE 2:

Weave: 4/1 Satin + 39D antistatic filament grid woven
Yarn count: 2/26 Ne
Fabric composition: Wool 46% + FR Viscose 42% + Polyamide 7% + Para Aramid 4% + Antistatic fibre 1%

The said fabric undergone pre-treatment and washing with hot water to remove impurities, dyeing the fabric with low affinity reactive dye with dye fixing to provide the fabric excellent fastness properties, the fabric is dyed with acid dye for wool and polyamide part, treating the fabric with hydrophilic softener or optionally, treating the fabric with anti-microbial, water and oil repellents, and stain release agents.