Technical Background

This invention relates to polyol and blocked isocyanate mixture one component binder developed to ensure that flexible and non-adhesive products are obtained depending on the binder properties in textile printing ink applications, and that energy costs are reduced by way of lower fixing temperature and risk of deformation is reduced on any given fabric.

Prior Art

Primarily four polymer structures, namely, polyurethane, acrylic, PVC and silicone, are used as binders in textile printing ink applications; whereas textile printing inks obtained from the listed binders as known today have following disadvantages.

When textile printing inks made from acrylic polymer is applied on the fabric by way of screen printing, fixing in 1,5 minutes at 160°C is required in order to create a film on the fabric surface. Surface tackiness is an important problem on outputs from acrylic polymer. Water molecules present in acrylic emulsion lead to problems on the part of the users because of evaporation at the time of application, which, in turn, leads to increased viscosity, failure of textile printing ink to get passed through the silk mould. Increased viscosity sometimes causes that ink is no longer eligible for use, which means more costs to be incurred by the applying party. Aqueous emulsions of acrylic polymers lead to decrease in washing fastness. With water-based acrylic polymers, it is not possible to get thick films, also known as high-density printing. Contraction occurs as water is present in the system; hence a homogenously distributed film cannot be obtained. In addition, a 1 ,5-minute fixing at 160°C is another factor that increases costs of the application.

Fixing at given temperature also disfigures the fabric, causing yellowing, contraction etc. Printing performed by using acrylic emulsions bears the risk of formaldehyde release, which is a prohibited chemical substance. This may have adverse effects on the health of living creatures.

When textile printing inks made by using water-based polyurethane dispersion are applied on the fabric by screen printing, a 1 ,5-minute fixing at 160°C is required in order to create a film on the fabric surface. Even though polyurethane dispersions do not create an adhesive film like acrylic emulsions, water molecules present in dispersion are difficult to work on. As water evaporates, viscosity increases and the output is rendered ineligible for use. Hydrophilic functional groups that are present in polyurethane dispersions may lead to reduced washing fastness. With water-base polyurethane dispersion, it is not possible to get thick films, also known as high-intensity printing. Contraction occurs as water is present in the system; hence a homogenously distributed film cannot be obtained. In addition, a 1 ,5-minute fixing at 160°C increases costs of the application.

When textile printing inks made by using PVC is applied by screen printing, even though they work on screen well and thick film outputs, also known as high- density printing, is concerned, they are still not much preferred in that they fail to meet ecological standards. Also, a 1 ,5-minute fixing at 160°C is required so that PVC-based textile printing ink creates a film. This increases energy costs to be incurred, and disfigures the fabric quality.

Since silicone-based textile printing inks are used in combination with platinum catalyst, it is a high-cost polymer. Since they are applied as two components by serigraphy, the life of the mixture is short, so redundant material turns out to be waste. This means extra cost. Silicone curing requires 1 ,5 to 2 minutes of time and temperature as high as 160°C, which increases energy costs and disfigures the fabric quality.

Acrylic emulsion binders are also used for producing digital ink jet printing inks that contain organic pigments apart from screen printing inks. Digital ink printing inks that contain present acrylic emulsion binder cause problems such as quick drying. These binders may cause congestion at the nozzles due to dryness.

Objective of Invention Objective of this invention is to use polyol and blocked isocyanate mixture one component binder in textile ink applications whose outputs are flexible and non- adhesive film on the fabric.

Objective of this invention is to prevent passing through the silk screen troubles in screen printing or rotary screen printing that occurs other binders mentioned above because of water evaporation because polyol and blocked isocyanate mixture one component binder contains no water.

Objective of this invention is to prevent congestion at the nozzles in case of digital ink jet printing because polyol and blocked isocyanate mixture one component binder contains no water and does not come in an emulsion structure.

Objective of this invention is to ensure that a properly thick film layer, also known as high-density printing, is obtained on the textile fabric surface by way of using polyol and blocked isocyanate mixture one component binder in textile ink printing applications, and to provide better washing fastness because the binder contains no water-soluble groups. Objective of this invention is to decrease energy costs and also to prevent deformation of the fabric as binder allows lower temperatures as 110°C and shorter timing as 0,5 to 1 minute compared to present day textile printing applications.

Detailed Description of Invention

Polyol and blocked isocyanate mixture as is used in textile ink printing applications is a one component binder. The binder is composed of blocked isocyanate, which is pure or contains organic solvent, and polyol mixture. Blocked isocyanate contained blocking agents to inhibit reacting with polyols at room temperature. These are blocking agents such as diethylmalonate, e- caprolactam, 3,5- dimethylpyrazole, methylethylketoxime. Blocking isocyanates may come in pure or contain harmless solvents as butyl acetate. Depending on the type of blocking agent, the blocking remains at higher temperatures than room temperature.

The pure or harmless solvent-based blocked isocyanate systems react with polyether polyol or polyester polyol. For this reason, linear or branched diamines may also be used instead of polyols. A mixture of polyol and diamine compounds may also be used.

Polyols and isocyanates have a wide range of use in two-component polyurethane systems. Scope of this invention relates to the use of one component polyol and blocked isocyanate binding mixture in production of textile printing ink. In this one component binder mixture, the blocked isocyanates that do not get reactive at room temperature but unblocked due to increase in heat, hence they react with polyols.

Binder contains no water. The one component binder that functions to produce textile printing ink is thickened with proper thickeners, defoamed with anti- foaming agent and rheology is regulated with rheology modifiers. Glycerine, diethylene glycol, propylene glycol, polyethylene glycol, triethylene glycol, terephthalate esters, sebacate esters, phosphate esters, citrates, adipates, benzoates, maleates as well as plasticizer in polymeric structure are added to the textile printing inks as plasticising and elasticising agents. Likewise, organic pigments and inorganic pigments such as titanium dioxide, calcium carbonate, fillers such as talk, clay and viscosity regulating agents such as silica and dispersing agents are added in case of coloured printings as might be needed.

The resultant products applied on the textile surface by way of, say, screen printing or digital ink jet technique with flash cure or without flash cure. Fixing is applied to thus obtained printed textiles for 0,5 to 1 minute at and above 1 10°C. Resultant surfaces are non-adhesive and flexible. The aforecited additional chemicals may be mixed into them at miscellaneous ratios.

In textile ink printing applications, polyol and blocked isocyanates mixture one component binder may be used alone or in combination with the aforecited additional chemicals by making the same into printing inks to be applied by way of screen printing, rotary screen printing, digital ink jet printing, fabric surface bathing, doctor blade, spraying interalia other techniques.

Example Formula

1 ) The following formula may be given as an example for screen printing:

Polyester polyol at 45%

Blocked isocyanates at 45%

Glycol at 5%

Anti-foam at 0,5%

Thickener at 1 ,5%

Pigment at 3%

When white printing is requested, titanium dioxide up to 45% and dispersing agent up to 2% may be added. 2) The following formula may be given as an example for digital ink jet printing: Polyester polyol at 40%

Blocked isocyanates at 40%

Solvent at 15%

Pigment at 5%

Printing flexibility, washing fastness, adhesiveness and film rigidity may be changed by adapting the aforecited additional chemicals and the given ratios.