Cross Reference to Related Applications

The present application claims priority to UK patent application number 2008910.8 filed 11 June 2020, herein incorporated by reference in its entirety for all purposes.

Technical Field

The present invention is directed to an aqueous cleaning composition in the form of a liquid for cleaning the surface of an electronic device. In particular, the aqueous cleaning composition comprises 0.075- 0.15% w/w anti-static agent sold under the tradename Crodastat 400 and 0.1-2.5% w/w of a combination of non-ionic and anionic surfactants, wherein the composition does not include an alcohol having up to 5 carbon atoms as a solvent.

Background Art

Formulations which are suitable for cleaning electronic gadgets are known. However, most of these formulations include harsh chemicals, such as alcohol or ammonia. For example, US 4 129505 discloses an anti-static composition having 90 - 98% w/w of ethanol.

In addition, these compositions are often somewhat ineffective in preventing dust from gathering on the surface of the electronic device.

The use of such compositions on the surface of the screen of an electronic device can result in damage to the casing which in turn can lead to damage to the internal components of the electronic device.

EP 1 160 313 to The Procter & Gamble Company (P&G) discloses a chemical cleaning composition for cleaning household and office equipment comprising 0.001-99.99% of a fluorinated carbon compound, 1- 99% of an organic solvent, such as alcohol, and 0.0001-10% of other optional ingredients. P&G notes that electronic equipment will suffer damage from contact with water and most other liquids.

On its homecare website, Croda discloses an office cleaner for electrical items that comprises water, surfactant, antistatic agent, odour neutralizer, solubiliser, and fragrance (address at https://www.crodahomecare.com/en-gb/products-and-application s/product-finder/product/2582/

Crodastat_400#tab-collapse-formulation).

KR 10-2017-0135353 to the Korea Research Institute of Chemical Technology (KRICT) discloses an eyeglass detergent composition not containing alcohol and being excellent in antibacterial properties. Instead of alcohol, KRICT utilizes 2-15% of an ethylene glycol solvent. KRICT notes that detergency is lowered when the formulation contains less than 2% of the ethylene glycol solvent.

A need remains for an effective electronics gadget cleaning formulation that does not include harsh chemicals.

Summary of the Invention

According to the present invention there is provided an aqueous cleaning composition in the form of a liquid which comprises 0.075-0.15% w/w anti-static agent sold under the tradename Crodastat 400 and 0.1-2.5% w/w of a combination of non-ionic and anionic surfactants wherein the composition is alcohol- free.

Description of Embodiments

The present invention is directed to an aqueous cleaning composition in the form of a liquid for cleaning the surface of an electronic device. In particular, the aqueous cleaning composition comprises 0.075- 0.15% w/w anti-static agent sold under the tradename Crodastat 400 and 0.1-2.5% w/w of a combination of non-ionic and anionic surfactants, wherein the composition does not include an alcohol having up to 5 carbon atoms as a solvent.

The anti-static agent is sold by Croda under the tradename Crodastat 400. The antistatic agent is present at a level of 0.075 - 0.15% w/w. Applicants were surprised to learn that this antistatic agent was effective at this level because higher concentrations are recommended by the supplier.

Preferably the level of the combination of non-ionic and anionic surfactants is from 0.1 - 2.5% w/w. More preferably, the level of surfactant is from 0.2 - 2.0% w/w. Even more preferably the level of surfactant is from 0.3 - 1.5% w/w. Most preferably, the level of surfactant is from 0.5 - 1.0% w/w. The anionic surfactants can be selected from, but not restricted to, sodium lauryl sulfate, sodium lauryl ether sulphate, alkyl benzene sulphonic acid, sec-alkane sulphonates, alcohol sulphates or mixtures thereof.

The non-ionic surfactants can be selected from, but not restricted to, lauryl alcohol ethoxylates, polyglucosides, amine oxides, sorbitan esters or mixtures thereof.

Preferably the composition further comprises a preservative. The preservative is selected from, but not restricted to or combination of chloroisothiozolinone, methylchloroisothiozolinone, formaldehyde, phenoxyethanols, benzoic acid, sorbic acid or mixtures thereof.

Preferably, the preservative is present at a level of 0.001 - 0.01% w/w.

The composition can include further excipients such as a buffer, fragrance, dye or biocidal agent.

The composition of the present invention can comprise 0.02 - 1.0% w/w of an antistatic agent, 0.1 - 2.5% w/w of a combination of non-ionic and anionic surfactants and water.

Preferably, the composition of the present invention can comprise 0.05 - 0.5% w/w of an antistatic agent, 0.2 - 2.0% w/w of a combination of non-ionic and anionic surfactants and water.

More preferably, the composition of the present invention can comprise 0.075 - 0.15% w/w of an antistatic agent, 0.3 - 1.5% w/w of a combination of non-ionic and anionic surfactants and water.

Most preferably, the composition of the present invention can comprise 0.075 - 0.15% w/w of an antistatic agent, 0.5 - 1.0% w/w of a combination of non-ionic and anionic surfactants and water.

Preferably the composition further comprises a preservative at a level of 0.001 - 0.01% w/w.

Preferably the composition does not include ammonia. The composition can comprise 0.075 - 0.15% w/w of an antistatic agent, 0.5 - 1.0% w/w of a combination of non-ionic and anionic surfactants, 0.05 - 0.5% w/w anti-fogging agent, 0.01 - 0.05% w/w pH balancer, 0.001 - 0.005% w/w preservative and water.

The composition can consist essentially of 0.075 - 0.15% w/w of an antistatic agent, 0.5 - 1.0 % w/w of a combination of non-ionic and anionic surfactants, 0.05 - 0.5% w/w of an anti-fogging agent, 0.01 - 0.05% w/w of a pH balancer, 0.001 - 0.005% w/w of a preservative and water.

The composition can consist essentially of 0.075 - 0.15% w/w of an antistatic agent, 0.5 - 1.0 % w/w of a combination of sodium lauryl sulphate and lauryl alcohol ethoxylate, 0.05 - 0.5% w/w of an alcohol ethoxylate propoxylate, 0.01 - 0.05% w/w of sodium bicarbonate, 0.001 - 0.005% w/w of methyl chloroisothiazolinone-methylisothiazolinone and water.

The composition can have a pH ranging from 6 to 12.

For the avoidance of doubt, in the context of the present invention the term 'alcohol-free' means that the composition does not include an alcohol having up to 5 carbon atoms as a solvent. As demonstrated in the following example, the drying time is surprisingly on par with formulations that contain alcohols even though the formulation is water-based. Additionally, there was no damage to the devices, contrary to the teachings of P&G's EP 1 160313.

For the avoidance of doubt, in the context of the present invention the amounts of each active component are based on the standard commercial preparations. For example, the amount of the sodium lauryl sulfate as given in Table 1 is based on the amount surfactant Galaxy 780 added to the composition, of which sodium lauryl sulfate is only present at a 28% w/w concentration level.

The following examples below illustrate exemplary formulations as well as preferred embodiments of the invention. It is to be understood that these examples are provided by way of illustration only and that further compositions and articles may be produced in accordance with the teachings of the present invention.

Examples The present invention will now be described in more detail with reference to the accompanying examples. The examples are not intended to be all inclusive or limit the scope of the invention.

Table 1

The compositions can be made as follows - An aqueous pre-mix of the Galaxy 259, Galaxy 780 surfactants and fragrance is prepared. The Crodastat 400 and Berosol EC are added to this mixture with additional water. An aqueous solution of sodium bicarbonate is added to the resulting mixture. Lastly, the Microcheck preservative is added with the required water to obtain the desired volume. The formulations shown in Table 1 were tested on the surface of an LED TV.

The key objective of the study was to find the optimum concentration of Crodastat 400 at which it shows effective dust repellant property. The test was performed as follows:

1. The surface of the LED TV was divided into two equal parts. The one part was sprayed with 0.7ml water 2 times and the other part was sprayed 2 times with an example formulation.

2. Both the parts were wiped with soft tissues to make sure the spread of the product is even throughout the screen surface and were allowed to dry. 3. The TV was left undisturbed in the normal conditions (atmospheric temperature and pressure) for one week.

4. On the 7 ^th day, both the parts of the TV were wiped off by a wet tissue. 5. The tissues were visually observed for the dust accumulation on them.

6. Similarly, the experiment was repeated for all the other formulations as described in Table 2.

7. A visual inspection of the screen surface was performed. The application of the compositions is set out in Table 2.

Table 2

The results of the tests carried out for each formulation are summarized in Table 3 below. Table 3

As can be seen from the results shown in Table 3, the product showed better dust repellent property with an increase in the concentration of the Crodastat 400. Concentrations of 0.10% and above showed the best dust repellence. This concentration is lower than the concentration recommended by Croda for this raw material. A further study was carried out to confirm that the use of a formulation of the present invention to clean the screen of an electronic gadget does not cause any visual damage (e.g. any effect on picture quality such as double screen, half screen, any line or spot during viewing due to any kind of product penetration in the form of droplets) or physical damage (product residue streaks and scratches) during deleterious testing.

Before initiating the study, Day 0 observations were recorded for all appliances to be tested with respect to screen and electronics performance. 0.7ml of Example 4 in Table 1 was sprayed directly on all the appliances screen per spray.

The number of sprays applied to each screen is given in the Table 4 below:

Table 4

Each of the screens was tested over a period of 14 days. During the test the screens were wiped with clean microfiber cloths. The same wipes were used for carrying out the testing on all the screens, without washing them during the test, to recreate real life usage scenario. All the appliances were switched off and unplugged before initiating the test except smartphone. The protocol for the study was as follows: a) The formulation was directly sprayed in 'spray mode' (no. of sprays as mentioned above for each appliance respectively) and wiped/cleaned off using a microfiber cloth without any delay time. b) The surface of the device was allowed to dry completely before repeating the process and to prevent buildup of the product on appliance's screen. c) The process was repeated until the total number of sprays as shown in Table 5 was completed. d) At the end of every day, the devices were checked for any 'deleterious effect' (performance) by switching them 'ON'. e) The screen of each device was checked for any physical damage of the screen or picture quality such as double screen, half screen, any line or spot during viewing due to any kind of product penetration in the form of droplets.

The results of the testing are shown in Table 5 below: As can be seen from the results shown in the Table 5 above, the composition of the present invention is safe to use on the screens of laptops, LED TV & smartphones. There was neither any change in the performance of the appliances nor any adverse effect on the surface of these appliances. The study was done using direct application of the product to depict "stress case scenario" on the screen of all the electronic appliances.

A further study was carried out to determine the difference in the drying time between the composition of the present invention (which is alcohol-free) and a known cleaner (which contains isopropyl alcohol or IPA). The study was performed on the screen of a LED TV. The screen of a LED TV was sprayed once (0.7ml) with a known cleaner. The screen was then wiped 5 times with a microfiber cloth.

The formulation of the known cleaner is as follows:

As soon as the screen was wiped, a timer was started to record the time taken (seconds) for the screen to dry completely. The process was repeated for a total of 10 times and the drying times were recorded. The results are shown in the Table 6 below:

Table 6

As can be seen from the results in the Table above, there is a negligible difference in the drying time (1.27 seconds) of the screen when wiped between the known product and the composition of the present invention. The absence of alcohol from the compositions of the present invention does not result in a longer drying time which would have been expected.

An advantage of the present invention is that there is provided a composition which is safe for cleaning the screens of electronic devices such as televisions, tablets, smartphones, computers, smartwatches, digital camera.

The composition of the present invention can clean greasy stains, dust & fingerprints, provide the screen with an anti-static and anti-fogging properties, leaves no streaks or residue, and is free from alcohol, ammonia, phosphates and other harsh chemicals.

The present invention is not intended to be limited to the exemplary embodiments described herein. Further modifications can be made without departing from the scope of the invention described herein.