CLIAMS:We claim:
1) A water repellent composition for paper which comprises:
i) Quilon C and
ii) water
2) The water repellent composition for paper as claimed in claim 1 in which the ratio of Quilon C with water is 1:20.
3) The water repellent composition for paper as claimed in claim 1 in which preferably the ratio of Quilon C with water is 1:10.
4) The water repellent composition for paper as claimed in claim 1 wherein after treatment of the composition the coefficient of friction of the paper increases.
5) The process for preparing water repellent composition for paper which comprises;
i) Quilon C
ii) Water
With mixing of the above two components homogeneously.
6) The process for preparing water repellent composition for paper as claimed in claim 5 in which the ratio of Quilon C with water is 1:20.
7) The process for preparing water repellent composition for paper as claimed in claim 5 in which preferably the ratio of Quilon C with water is 1:10.
8) The paper coated with the water repellent composition as claimed in claim 1 wherein after treatment of the composition the coefficient of friction of the paper increases.
9) A water repellent composition for paper substantially as hereinbefore described with particular reference to the accompanying drawings.
10) A paper coated with the water repellent composition substantially as hereinbefore described with particular reference to the accompanying drawings.
,TagSPECI:FIELD OF THE INVENTION

This invention relates to the composition for forming a repulpable, water resistant coating on a porous paper sheet material and in particular, this invention relates to a water repellent composition coated on paper bag so that water cannot stick on the surface on the paper. The invention relates furthermore to the process of preparing the water repellent composition for paper.

BACKGROUND OF THE INVENTION AND THE RELATED PRIOR ART

Perishable food products such as frozen meat, fish and vegetables are shipped, stored and displayed for sale in packages formed of corrugated paperboard coated with a water resistant or repellent material, the most widely used coating being a wax coating. The wax coating renders the packages resistant or repellent to water and impermeable to water vapour.

Such packages, however, have a serious disadvantage in that they are essentially non-repulpable. Repulping refers to the art of recycling waste paper products including paperboard to provide a reusable wood pulp. Recyclability of waste paper products is of growing importance in efficiently employing available wood fibre resources and in curtailing the amount of waste which is either combusted or disposed of in landfill sites.

The document WO1999045059 relates to a coating composition for the linerboard of corrugated paperboard provides water and grease resistance but is water vapor permeable, and thus permits a different mode of manufacture of corrugated paperboard when aqueous adhesives are employed in the assembly of the linerboards and corrugated medium; in particular the linerboards may be coated with the coating composition prior to assembly of the corrugated paperboard because the water vapor permeable coating permits escape of the water of the aqueous adhesive, during drying of the assembled components of the corrugated paperboard.

The other document JP2012219220 describes a water-repellent oil-resistant agent and water-repellent oil-resistant paper which can exhibit excellent water repellency and oil resistance as well as high safety. The water-repellent oil-resistant agent includes 0.1-10 mass% of a fluorine-containing copolymer obtained by polymerizing a 6C or less perfluoroalkyl group-containing compound; and 1-10 mass% of an anionic polyacrylamide. The water-repellent oil-resistant paper is manufactured by treating unsized paper with the water-repellent oil-resistant agent. The method for manufacturing the paper is also provided.

The patent document JP2012036510 states a water repellent paper which is little in water repellency decline by heat and has excellent anti-slip properties without applying an undercoat agent. A water repellent paper is provided with a surface treatment layer comprising a polyolefin-based resin aqueous dispersion (A), a wax-based water repellent agent (B) and a pigment on at least one surface of a paper support. The water repellent paper contains 0.5-40 pts. mass of a pigment based on 100 pts mass of a mixture in which (A) and (B) are mixed so that the solid mass ratio.

The other document JP2011117107 discloses a water-repellent paper hardly causing deterioration of water repellency with heat and having excellent anti-slip property without applying an undercoating agent. The water-repellent paper is produced by coating at least one surface of a paper support with a mixture containing (A) an aqueous dispersion of a polyolefin resin, (B) a wax-based water-repellent, and a tackifying agent, wherein the (A):(B) mass ratio is 1:99 to 50:50 as solid basis and the content of the tackifying agent is 0.5-20 pts mass based on 100 pts mass of (A)+(B).

According to the document JP2008214815, an undercoating liquid that is applied to a base paper to be coated with a water repellent before coating with the water repellent so that the water repellent to be coated later is prevented from sinking by a heat influence, a water repellent paper having a coated layer of the undercoating liquid formed on paper and a water repellent layer formed on the coated layer and to provide a method for producing the water repellent paper. The undercoating liquid for a water repellent contains an emulsion of an anionic polymer (A). The water repellent paper has a coated layer obtained by using the undercoating liquid for a water repellent and a water repellent layer. The method for producing a water repellent paper has a process for coating a base paper with the undercoating liquid for a water repellent and drying the base paper, a process for coating the prepared coated layer with a water repellent and drying the coated water repellent.

The invention of the document JP2013072153 provides coated paper for a private water repellent treatment that is excellent in film forming property when a water-repellent agent is coated on the surface and is also high in surface strength, and to provide water-repellent paper obtained from the coated paper. There is provided coated paper for private water repellent treatment formed by coating a coating liquid on a surface of a base paper. The base paper is acidic paper that includes an internally added rosin-based sizing agent. The coating liquid includes a cationic styrene resin, an acrylamide resin and a vinyl alcohol-based polymer. It is effective that the vinyl alcohol-based polymer has a polymerization degree of 1,200 or more and 2,200 or less and a saponification degree of 97% or more.

According to the invention JP2009114585, an undercoating agent for water-repellents capable of sufficiently getting the repelling effect of the water-repellents. The undercoating agent for water-repellents is an emulsion produced by the emulsion polymerization of (B) a hydrophobic vinyl monomer having a 4-18C alkyl group in an aqueous solution of (A) an anionic polymer dispersant containing an alkali salt of a copolymer obtained by reacting at least an [alpha]-olefin with maleic anhydride, and has an effective component weight ratio of (A)/(B)=(40-75)/(60-25), preferably the anionic polymer dispersant (A) further contains an alkali salt of a copolymer obtained by reacting a styrene compound with (meth)acrylic acid. The paper making method comprises the application of the undercoating agent for water-repellents followed by the application of a water-repellent.

A method of monitoring and controlling one or more types of hydrophobic contaminants in a papermaking process is disclosed. The methodology utilizes the measurement of hydrophobic dyes, which are capable of fluorescing and interacting with the hydrophobic contaminants. In addition, a method of determining the relative size of the hydrophobic contaminants is disclosed as well which has been stated in document of patent application 7914/DELNP/2011.

The document JP2006161180 states that the moisture-proof/water-repellent food packaging paper given by mixing a rayon fibre thereinto, having a Japanese paper-like feeling, and having water resistance. This packaging paper comprises the food packaging paper which has a basis weight of 9-30 g/m and contains the rayon fibre, wherein the rayon fibre having a size of 0.5-5 dtex and a fibre length of 1-7 mm is mixed into the paper in an amount of 5-70 mass%, a wet paper strength reinforcing agent is internally or externally added to the paper, a wet breaking length (longitudinal) Lw [Lw=(S*103)/(g/9.81), wherein S is a wet tensile strength (kN/m) for an immersion time of 10 min according to JIS P8135; and g is a basis weight (g/m2) in a wet state after water is removed by blotting paper according to JIS P8135] is made to be 1.2 km or more, the packaging paper is coated with a water repellent, and a degree of water repellence is made to be R7 to R10.

The other document JP2005290609 provides water-repellent paper having excellent water repellence. The water-repellent paper is characterized as follows. The water-repellent paper is obtained by carrying out papermaking of a paper stock containing water-repellent cellulose prepared by reacting (A) cellulose with (B) a water-repellent compound containing a functional group reactive with hydroxy groups of the cellulose. The functional group reactive with the hydroxy groups of the cellulose in the component (B) is characterized as preferably one or more kinds selected from an isocyanate group, an amino group, an epoxy group, a carboxy group, an anhydrous carboxy group, an imide group, an aldehyde group and a halide.

The document JP2004183165 discloses a water-repellent composition for preventing the lowering of water-repellence of a stored water-repellent liner having degraded liner paper quality by the increase of waste paper content. The water-repellent composition contains a water-repelling material comprising a mixture emulsion containing paraffin wax, a tackifier and an emulsifier and a synthetic resin emulsion having a Tg (glass transition temperature) of -10 to +60[deg.]C. The ratio of the synthetic resin emulsion is 10-60 wt. % in terms of solid based on the solid component of the total water-repellent composition and the content of the paraffin wax is 10-60 wt. % based on the solid component of the total water-repellent composition.

The other document US5626945 describes paperboard having a water-repellent coating which includes a polymer matrix/wax mixture and is applied to the paperboard as an aqueous formulation. The polymer matrix includes polymer chains which are ionically cross-linked through pendant carboxylic acid groups to provide, together with the wax, a substantially continuous, water-repellent film which more readily breaks down under the alkaline conditions of repulping.

According to the document US4117199 the invention discloses a coated paper having a moisture and water-proof coating thereon is produced by coating a paper substrate with an aqueous emulsion containing a synthetic rubber latex and a wax emulsion in an amount of the solid wax of 5 to 200 parts by weight per 100 parts by weight of the solid synthetic rubber and, then, drying the coated paper at a temperature the same as or higher than the melting point of the wax. The resultant paper is highly capable of repulping.
None of these above patents, however alone or in combination, disclose the present invention. The invention consists of certain novel features and a combination of parts hereinafter fully described and particularly pointed out in the appended claims, it being understood that various changes in the details may be made without departing from the spirit, or sacrificing any of the advantages of the present invention.

SUMMARY OF THE INVENTION

This invention relates to a water repellent composition for paper and in particular, this invention relates to a water repellent composition coated on paper bag so that water cannot stick on the surface on thepaper. The invention relates furthermore to the process of preparing the water repellent composition for paper.

DETAILED DESCRIPTION OF THE INVENTION WITH ACCOMPANYING DRAWINGS

For the purpose of facilitating an understanding of the invention, there is illustrated in the preferred embodiment thereof, from an inspection of which, when considered in connection with the following description, the invention, its construction process, and many of its advantages should be readily understood and appreciated.

Water repellent coatings are the most commonly used protection in packaging. Safepack offers water resistant coatings for paper / board which are designed to give water resistance to food contact packaging materials & imparts water barrier properties to the packaging.

The principal object of the invention is to providea water repellent composition for paper.

The other embodiment of the invention is to provide a process for preparing a water repellent composition coated on paper bag so that water cannot stick on the surface on the paper and its use for producing packaging fishery products, fruits and vegetables.

The other embodiment of the invention is to provide the water repellent composition coated on paper bag so that water cannot stick on the surface on the paperwhich is made of quilon C.

The other embodiment of the invention is to provide the compositions is that treated materials dried in the neighborhood of 2200 do not suffer significant discoloration or tenderization if inadvertently overheated because of excessive drying time. For the same reason, the compositions of our invention are especially adaptable to high temperature, high speed processing conditions.

It is a general object of the invention to provide the coated paper also exhibits improved release characteristics and resistance to blocking and is particularly well-suited in corrugated box constructions used in shipping containers for perishable food items such as meats, poultry, fishery products, fruits and vegetables.
One feature of the invention is the water repellent paper or board is that it does not allow enterprises to suppress adulterated goods and makes it convenient for consumers to identify and distinguish false goods, and also protects the legal interest of the enterprises and the consumers which is good for the enterprises to enhance brand image, products image and company image.

Understanding that it is very important for the end user to ensure that the product available in the market is of the right source and quality, some uniqueness has to be incorporated in the pack to safeguard its originality and to provide advantageous features.

The aim of the present disclosure is to develop and manufacture the hydrophobic paper which has a specific characteristic maintaining the technical aspects and to protect packaged material from damage.

The process for preparing water repellent composition for paper which comprises the Quilon C is mixed with water in ratio of 1:20 more preferable 1:10.

The novel features that are considered characteristic of the present invention are set forth with particularity in the appended claims. The invention itself, however, both as to its organization and its method of operation, together with additional objects and advantages thereof, will best be understood from the following description of certain specific embodiments, when read in connection with the accompanying drawings, in which:

FIG. 1 illustrates the normal paper, in accordance with an exemplary embodiment of the present disclosure;

FIG. 2 illustrates the water repellent coated paper in accordance with an exemplary embodiment of the present disclosure;

It will be appreciated that the use of the paper or bag coated in accordance with the invention improves the repulpability of the box so that containers made from such paper may be more readily and more economically recycled than boxes made of conventionally (wax) coated water-repellent paperboard, and provides a recycled pulp of improved quality. Thus, it has been observed that under acidic conditions; i.e., below about pH 7, the ionic cross-linking between adjacent carboxylic acid groups of the polymer matrix provides a highly water resistant or hydrophobic film on the paper surface which is of sufficient strength and integrity to withstand typical shipping and storage conditions encountered when shipping ice-packed perishables.

It has also been observed that a paper coated according to the present invention exhibits improved repulpability as compared with water-repellent boards such as wax-coated boards and boards coated with polyethylene resin or extrudable film-forming thermoplastic resins such as polypropylene, polyamides, and ethylene/vinyl acetate co-polymers as well as polyolefin coatings, to name a few.

It is further believed that the network of ionic crosslinking is not as stable to conventional alkaline media such as sodium hydroxide-based systems used in repulping as chemically cured compositions; i.e., coating compositions having covalent bonds formed by chemical reaction and/or heat. That is, under alkaline conditions; i.e., substantially above about pH 7, and especially under typical repulping conditions of pH 8 to 11 and 100° F. to 160° F., it is believed that the ionic bonds of the coated paper of the invention more readily disassociate so that the coating breaks into smaller fragments faster .

In addition to facilitating repellent of the water, the coating of the invention is believed to provide improved release characteristics (release and high slip) and an increase in the glass transition temperature of the protective layer as compared with conventional coated paper of the type used in providing water-repellent shipping containers, to provide increased resistance to blocking.

Additionally, board produced in accordance with the present invention exhibits improved resistance to blocking under warm and humid conditions. This generally improves the handling properties of the paper or bag in relation to stacking of flattened-out paper or bag and conveyance of the board through the stages of manufacture, and limits blocking of adjacent boxes in shipment and storage.

Example:

A coating for application to a board was prepared. The mixture Quilon C has positive charge which has strongly bonded with negative charge of the substrate. Due to the formation of hydroxyl bridge, the hydrophobic attains a contact angle of more than 900 which reaches the contact angle like lotus leaf of 1700 i.e., contact surface of 2-3 %.

The result of the treated paper is shown in Table 1
Table 1
Parameters Semi extensible before coating Semi extensible after coating “Quilon C” High porous before coating High porous after coating of “Quilon C”
Grammage (g/m2) 73 74 84 85
Burst Index (KN/g) 4.72 7.24 5.48 5.84
Burst Factor ( no Unit 65 57.29 65.23 68.7
Tensile Index MD ( Nm/g) 61.75 64.45 79.33 68.41
 
Tensile Index CD ( Nm/g) 54.6 47.68 50.6 46.89
Stretch MD (%) 6.7 8.3 7.2 8.3
Stretch CD (%) 9.4 9.4 10 10
TEA Index MD (j/g) 2.8 3.7 3.9 3.9
TEA Index MD (j/g) 3.5 3.1 3.5 3.2
Air Resistance Gurley (Sec/100ml) 15 15 5 5

Wet-strength paperboard coated in accordance with Example 1 was defibered in a laboratory blender operated at 120°-140° F. /pH of 10-11/2.5% consistency.

Finished stock was further diluted down to 0.2% consistency with tap water. Hand sheets were made from the stock using a standard TAPPI sheet mould. The sheets showed satisfactory defibering and were free from "stickies" after 40-60 seconds repulping time.

Conventional curtain-coating wax coated wet-strength board was defibered in the same device and conditions for comparison purposes. Paper-coating wax layers broke into small size agglomerates, which were visible and unacceptable for papermaking. Non-defibered lumps were also observed in the handsheet.
The test results of water absorption (Cobb-60) of water repellent treated paper at various timings are laid out in Table 2
Table 2
Time (in Minutes) Water Absorption (GSM)
15 NIL
30 NIL
45 5
60 5
75 10
90 15
105 15
120 20

The foregoing description of various and preferred embodiments of the present invention has been provided for purposes of illustration only, and it is understood that numerous modifications, variations and alterations may be made without departing from the scope and spirit of the invention as set forth in the following claims.

By way of conclusion it should be observed that the present invention which has been described above with particular reference, is not restricted to these embodiments described and shown exclusively by way of example, and that modifications and alterations obvious to a person skilled in the art are possible without departing from the inventive concept as disclosed in the appended claims.