GLUE STICK COMPOSITION

Abstract

A water based glue stick composition includes adhesive and nanocrystalline cellulose. The composition is contained in a glue stick that can be used for planar joining of substrates to one another. The substrates can include paper and/or cardboard such as printer paper, photo paper and cardboard paper.

Claims

1-13. (canceled)

14. A water based glue stick composition, the composition comprising: adhesive; and nanocrystalline cellulose.

15. The composition according to claim 14, wherein the nanocrystalline cellulose consists of cellulose hydrogen sulphate salt nanoparticles.

16. The composition according to claim 14, wherein the nanocrystalline cellulose consists of cellulose sulphate sodium salt nanoparticles.

17. The composition according to claim 14, wherein the nanocrystalline cellulose has a particle diameter in the range 2-8 nm, measured by atomic force microscopy.

18. The composition according to claim 14, wherein the nanocrystalline cellulose has a particle diameter in the range 2-5 nm, measured by atomic force microscopy.

19. The composition according to claim 14, wherein the nanocrystalline cellulose has a particle length in the range of 40-160 nm, measured by atomic force microscopy.

20. The composition according to claim 14, wherein the nanocrystalline cellulose has a particle length in the range of 44-108 nm, measured by atomic force microscopy.

21. The composition according to claim 14, wherein the nanocrystalline cellulose content is in the range 0.1-3 weight % based on the total weight of the composition.

22. The composition according to claim 14, wherein the nanocrystalline cellulose content is in the range 0.2-2 weight % based on the total weight of the composition.

23. The composition according to claim 14, wherein the nanocrystalline cellulose content is in the range 0.25-1.5 weight % based on the total weight of the composition.

24. The composition according to claim 14, wherein the adhesive is selected in the group consisting of starch, starch derivatives, polyvinylpyrrolidone, aqueous polyacrylates, polyvinyl alcohols and mixture thereof.

25. The composition according to claim 14, wherein the adhesive is selected in the group consisting of starch, starch derivatives and mixture thereof.

26. The composition according to claim 14, wherein the adhesive content is in the range 15-35 weight % based on the total weight of the composition.

27. The composition according to claim 14, wherein the adhesive content is in the range 17-32 weight % based on the total weight of the composition.

28. The composition according to claim 14, further comprising: a humectant.

29. The composition according claim 28, wherein the humectant content is in the range 5-30 weight % based on the total weight of the composition.

30. The composition according to claim 14, further comprising: a soap.

31. The composition according to claim 30, wherein the soap consists of sodium salt of fatty acid.

32. The composition according to claim 14, further comprising: an additive.

33. A glue stick, the glue stick comprising: an adhesive and nanocrystalline cellulose composition.

Description

EXAMPLE 1: PREPARATION OF A GLUE STICK ACCORDING TO THE INVENTION

[0050] Two different glue sticks have been prepared having the composition described in table 1 below

TABLE-US-00001 TABLE 1 Formula 1 Formula 2 (disclosure) (disclosure) % by weight % by weight Function Water 51.15 52.40 Solvent Glycerine 4810 (glycerin) 10.00 10.00 Humectant Neosorb 70/70 (sorbitol) 7.15 7.15 Humectant Tackidex 250 (corn starch) 25.50 24.50 Adhesive Sodium stearate 3.00 3.50 Soap Celluforce NCC 1.00 0.25 Additive (nanocrystalline cellulose) Foamaster MO2170 (Silica 1.30 1.30 Additive and oil blend) (antifoam agent) Acticide PHE 0.90 0.90 Additive (phenoxyethanol) (preservative) Total 100.00% 100.00%

[0051] The process of preparation for the composition of formula 2 is as follow:

[0052] 1st Step: Mixing (85-90° C.)

Laboratory equipment=Dissolver DISPERMAT® LC75−Dissolver disc Ø 60 mm.

[0053] For a laboratory preparation of 300 g, we heat between 85-90° C. 157.2 g of water and then introduce 30 g of Glycerin 4810+21.45 g of Neosorb®70/70 and 2.40 g of Foamaster® M02170. We stir at 500 rpm speed during 5 min and maintain the temperature between 85-90° C.

[0054] We add under stirring 0.75 g of Cellulose NCC and maintain 500 rpm speed and the same temperature during 5 min.

[0055] We increase the stirring speed to 1000 rpm and introduce at this stage 73.50 g of TACKIDEX® 250.

[0056] We stir during 15 min and maintain the temperature at 85-90° C.

[0057] We add 10.50 g of sodium stearate and stir during 15 min without changing stirring speed and temperature.

[0058] At the end, we add 2.70 g of Acticide® PHE and 1.50 g of Foamaster® M02170 and stir only 3 min at lower stirring speed (500 rpm).

[0059] 2nd Step: Filling (80° C.)

[0060] We pour immediately the preparation into the sticks.

[0061] 3rd Step: Cooling (65° C. to Room T° C.)

[0062] We let the sticks solidified at room temperature.

[0063] The same preparation process is used for preparing a glue stick of example 1 with the corresponding amount of each ingredient.

EXAMPLE 2: COMPARISON OF THE GLUING PERFORMANCES WITH A GLUE STICK NOT CONTAINING NANOCRYSTALLINE CELLULOSE

[0064] The gluing performance of the glue stick having the composition of formula 2 of example 1 according to the disclosure has been compared with the gluing performance of the glue stick having the same composition but without nanocrystalline cellulose (formula 3: comparative example out of the disclosure) and prepared as described in example 1 by the use of the following tests (Table 2).

TABLE-US-00002 TABLE 2 Formula 2 of example 1 Comparative (disclosure) formula 3 % by weight % by weight Function Water 52.40 52.65 Solvent Glycerine 4810 (glycerin) 10.00 10.00 Humectant Neosorb 70/70 (sorbitol) 7.15 7.15 Humectant Tackidex 250 (corn starch) 24.50 24.50 Adhesive Sodium stearate 3.50 3.50 Soap Celluforce NCC 0.25 — Additive (nanocrystalline cellulose) Foamaster MO2170 (Silica 1.30 1.30 Additive and oil blend) (antifoam agent) Acticide PHE 0.90 0.90 Additive (phenoxyethanol) (preservative) Total 100.00% 100.00%

[0065] The stick length (=total length placed) and the glue quantity used by 100 m (=weight of glue necessary to glue 100 meters of paper) have been assessed by using the following method at 23° C. and 50% RH, 7 days after manufacturing the glue stick, on 3 sticks of glue for each example:

[0066] 1—The glue stick in the tube is weighted (with the cap)

[0067] 2—Then the glue is placed by strips of 20 cm of Paper A4 80 g/m.sup.2 of reference Navigator or equivalent (=printer paper) in order to completely empty the tube of glue.

[0068] 3—The empty glue stick tube is weighted (with the cap).

[0069] Steps 1 to 3 are repeated with the 2 other glue sticks and the average is calculated.

[0070] For each tested glue stick, the number of pages totally covered and the length covered on the last page is determined, in order to be able to determine the total length placed, by using the following formula:

[0071] The Total length placed (m)=Number of pages covered×1.4+length placed on the last page.

[0072] The weight of glue necessary to glue 100 meters of paper is calculated using the following formula:

[00001]$\mathrm{Weight}\mathrm{of}\mathrm{glue}\mathrm{necessary}\mathrm{for}100\mathrm{metres}\mathrm{of}\mathrm{paper}=\frac{(\mathrm{Initial}\mathrm{weight}-\mathrm{final}\mathrm{weight}\left(g\right)\times 100}{\mathrm{Length}\mathrm{that}\mathrm{can}\mathrm{be}\mathrm{deposited}\left(m\right)}$

[0073] The setting time (=bonding time) has been assessed by using the following method at 23° C. and 50% RH on a paper A4 80 g/m.sup.2 of reference Navigator or equivalent, 7 days after manufacturing the glue stick, on 5 sticks of glue for each example:

[0074] 1—On a sheet of scrap paper, make a deposit to check whether it is uniform.

[0075] 2. Cut 2 strips of paper 80 g/m.sup.2 of 4 cm in width and 12 cm in length, then 2 strips of paper 80 g/m.sup.2 of 4 cm in width and 15 cm in length

[0076] 3. On the 1st strip of paper of 15 cm, place 2 layers of glue superimposed on the center of the strip.

[0077] 4. Position the 1st strip of 12 cm on the strip of 15 cm and apply pressure like a customer does when he glues 2 pieces of paper together (pressure with fingers on the assembling after glue deposit).

[0078] 5. When the test specimen is produced, start the chronometer.

[0079] 6. Every 5 seconds, gradually pull off the two paper strips until there is breakage between the 2 supports.

[0080] Beyond 30 seconds, perform the test every 10 seconds instead of 5 seconds.

[0081] The bonding time of a glue corresponds to the breakage between the 2 supports.

[0082] If the bonding time is greater than 2 minutes, indicate >2 minutes.

[0083] In the case where a single test specimen has not been sufficient, repeat the test using two new strips (12 and 15 cm), starting to pull off the two strips later.

[0084] 7. Repeat steps 3 to 6 for the 2nd strips of paper.

[0085] 8. Repeat steps 2 to 7 for the other glue stick to be tested.

[0086] The “Customer test” (=Quality of bonding of a glue stick over time Consumer Test) has been assessed by using the following method at 23° C. and 50% RH, one day and 7 days after manufacturing the glue stick (Consumer Test 1 day), or 1 week and 7 days after manufacturing the glue stick (Consumer Test 1 week) on 5 sticks of glue for each example:

[0087] The equipment consists in: [0088] Spiral notebook 60 g/m.sup.2 of reference Lyreco Budget 210×297 mm, 80 pages or equivalent [0089] Paper A4 80 g/m.sup.2 of reference Navigator or equivalent (=printer paper) [0090] Stiff-covered paper 200 g/m.sup.2 of reference Canson Mix Media Imagine or equivalent (=cardboard paper) [0091] Photo paper 250 g/m.sup.2 of reference HP Advanced or equivalent (=photo paper) [0092] Standardized roll of 1 kg [0093] Standardized roll of 2 kg.

[0094] The method is as follow:

[0095] 1. On a sheet of scrap paper, make a deposit to check whether it is uniform.

[0096] 2. Cut 8 strips of paper 80 g/m.sup.2 of 4 cm in width and 12 cm in length.

[0097] 3. On the 1st strip of paper, make a glue deposit (1 layer) on the center of the strip and glue it on the notebook sheet (do not glue strips on the back of notebook sheets).

[0098] 4. Apply pressure with the 1 kg standardized roller (1 forward-return pass, where the glue was deposited).

[0099] 5. Repeat steps 3 to 4 for the 7 other strips of 80 g/m.sup.2 paper. 6. Immediately close the notebook after gluing.

[0100] 7. Repeat steps 2 to 6 for the other supports to be tested and for the other products to be tested.

[0101] 8. Store the notebook in an air-conditioned room at 23° C./50% RH.

[0102] 9. After 1 h of test, and for each paper support to be tested, pull the first paper strip to determine the type of adherence encountered during tear-off. This test corresponds to the ageing interval T0.

[0103] 10. Repeat step 9 for the next 7 bands, after each ageing interval.

[0104] 11. Repeat steps 1 to 10 with the 2 kg standardized roller and with applying pressure like a customer does when he glues 2 pieces of paper together (pressure with fingers on the assembling after glue deposit=consumer usage).

[0105] The scoring obtained is as follow:

[0106] 10: The paper strip has fully adhered to the notebook sheet—The support breaks;

[0107] 7.5: The paper strip has partially adhered to the notebook sheet—The support partially breaks;

[0108] 5: The paper strip adheres slightly to the notebook sheet—The support partially does not tear;

[0109] 2.5: The paper strip adheres very slightly to the notebook sheet—The support does not tear and slight resistance is felt—Cohesive break

[0110] 0: The paper strip does not adhere at all to the notebook sheet—The support does not tear—Cohesive break

[0111] The results are indicated in table 3 below:

TABLE-US-00003 TABLE 3 Formula 2 of Comparative example 1 formula 3 Stick length (m) 45.6 34.6 Glue quantity used by 100 m (g/100 m) 16.0 20.4 Setting Consumer usage 50 55 time (s) Consumer Roll Printer paper 5 5 Test (1 kg) Photo paper 7.5 7.5 1 day Cardboard paper 2.5 2.5 Roll Printer paper 10 7.5 (2 kg) Photo paper 10 10 Cardboard paper 7.5 5 Consumer Printer paper 10 10 usage Photo paper 10 10 Cardboard paper 10 7.5 Consumer Roll Printer paper 10 2.5 Test (1 kg) Photo paper 7.5 5 1 week Cardboard paper 2.5 0 Roll Printer paper 10 10 (2 kg) Photo paper 10 10 Cardboard paper 7.5 7.5 Consumer Printer paper 10 10 usage Photo paper 10 10 Cardboard paper 10 2.5

[0112] Cardboard paper and photo paper are known to be more difficult to glue. It should be noted that the results obtained with the roll of 2 kg is close to the results obtained with the fingers (the roll of 1 kg is lighter than the fingers). As shown in table 3, the glue stick according to the present disclosure (formula 2) shows better results in term of stick length, glue quantity used by 100 m and consumer tests, in particular after 1 week and on cardboard paper.

[0113] Therefore the gluing performance of a glue stick containing the nanocrystalline cellulose is better than the gluing performance of a glue stick not containing nanocrystalline cellulose.

EXAMPLE 3: COMPARISON OF THE GLUING PERFORMANCES WITH COMPARATIVES GLUE STICK FORMULATIONS NOT CONTAINING NANOCRYSTALLINE CELLULOSE

[0114] The gluing performance of the glue stick having the composition of formula 1 of example 1 (disclosure) has been compared with the gluing performance of comparative formula 4 (comparative example) and of comparative formula 5 (comparative example) having the composition indicated in the following tables 4 and 5.

TABLE-US-00004 TABLE 4 Formula 4 (comparative example) Function Water 53.4 Solvent Glycerin 8.0 Humectant Monopropylene glycol 0.6 Humectant Starch 28.0 Adhesive Sodium stearate 10.0 soap Total 100.00%

TABLE-US-00005 TABLE 5 Formula 5 (comparative example) Function Water 46.0 Solvent Polyvinyl pyrrolidone 22.0 Adhesive Sodium stearate 7.00 soap Glycerin 11.0 Humectant Propylene glycol 4.0 Humectant Other 10.0 Biocide, perfume Total 100.00%

[0115] Each glue stick has been tested on 3 different types of paper (Printer paper 80 g/m.sup.2, Canson paper 200 g/m.sup.2 (cardboard paper) and Photo paper 250 g/m.sup.2) by making for each type of paper, a glue deposit on one side of the paper and add another paper on the glue deposit and then apply pressure with the 1 kg standardized roller (4 forward-return pass, where the glue was deposited). Peeling tests have been performed on each glued papers at 23° C. and 50% RH at 180° with a speed of 300 mm/min using the Standard method Finat FTM 1: peel adhesion (180°) at 300 per minute until the tearing of the paper according to the following method:

[0116] The unglue side of the papers is fixed on a metal plate engaged in the top jaw of the tensile apparatus. An extension is added to the leading edge (end of the glued paper). It is engaged in the lower jaw.

[0117] The evolution of the peeling linear load is drawn as a function of the shift.

[0118] The failure mode is identified (adhesive, cohesive, tearing of the paper . . . )

[0119] Tests specimen dimension are 25 mm×175 mm in machine direction.

[0120] The results are indicated in table 6 below:

TABLE-US-00006 TABLE 6 Canson paper Printer paper 200 g/m.sup.2 Photo paper References 80 g/m.sup.2 (cardboard paper) 250 g/m.sup.2 Formula 4 85 (+/−20) N/m 70 (+/−30) N/m  90 (+/−20) N/m (comparative example) Formula 5 <40 N/m <20 N/m Null (comparative example) Formula 1 105 (+/−20) N/m 100 (+/−15) N/m 100 (+/−20) N/m (disclosure)

[0121] The adhesion degree is higher for the glue stick according to the present disclosure (formula 1) whatever the type of paper used.

EXAMPLE 4: PREPARATION OF A COMPARATIVE GLUE STICK COMPOSITION

[0122] The gluing performance of the glue stick having the composition of formula 2 of example 1 (disclosure) has been compared with the gluing performance of comparative formula 6 (comparative example) having the composition indicated in the following table 7, and wherein the nanocrystalline cellulose has been replaced weight by weight by sodium carboxymethylcellulose.

TABLE-US-00007 TABLE 7 Formula 2 of example 1 Comparative (invention) Formula 6 % by weight % by weight Water 52.40 52.40 Glycerine 4810 10.00 10.00 (glycerin) Neosorb 70/70 7.15 7.15 (sorbitol) Tackidex 250 (corn 24.50 24.50 starch) Sodium stearate 3.50 3.50 Celluforce NCC 0.25 (nanocrystalline cellulose) Sodium 0.25 Carboxymethylcellulose (Blanose ™ REF CMC 7ULC by Ashland) Foamaster MO2170 1.30 1.30 (Silica and oil blend) Acticide PHE 0.90 0.90 (phenoxyethanol) Total 100.00% 100.00%

[0123] The process of preparation for the composition of example 6 (comparative example) is as follow:

[0124] 1st Step: Mixing (85-90° C.)

Laboratory equipment=Dissolver DISPERMAT® LC75−Dissolver disc Ø 60 mm.

[0125] For a laboratory preparation of 300 g, we heat between 85-90° C. 157.2 g of water and then introduce 30 g of Glycerin 4810+21.45 g of Neosorb®70/70 and 2.40 g of Foamaster® M02170. We stir at 500 rpm speed during 5 min and maintain the temperature between 85-90° C.

[0126] We add under stirring 0.75 g of Blanose™ REF CMC 7ULC by Ashland and maintain 500 rpm speed and the same temperature during 5 min.

[0127] We increase the stirring speed to 1000 rpm and introduce at this stage 73.50 g of TACKIDEX® 250.

[0128] We stir during 15 min and maintain the temperature at 85-90° C.

[0129] We add 10.50 g of sodium stearate and stir during 15 min without changing stirring speed and temperature.

[0130] At the end, we add 2.70 g of Acticide® PHE and 1.50 g of Foamaster® M02170 and stir only 3 min at lower stirring speed (500 rpm).

[0131] 2nd Step: Filling (80° C.)

[0132] We pour immediately the preparation into the sticks.

[0133] 3rd Step: Cooling (65° C. to Room T° C.)

[0134] We let the sticks solidified at room temperature.

EXAMPLE 5: COMPARISON OF THE GLUING PERFORMANCES WITH COMPARATIVE GLUE STICK COMPOSITIONS CONTAINING SODIUM CARBOXYMETHYLCELLULOSE

[0135] The gluing performance of the glue stick having the composition of formula 2 of example 1 (disclosure) has been compared with the gluing performance of the glue sticks wherein the nanocrystalline cellulose has been replaced weight by weight by sodium carboxymethylcellulose (Formula 6) by the use of the following tests:

[0136] The stick length (=total length placed) and the glue quantity used by 100 m (=weight of glue necessary to glue 100 meters of paper) have been assessed by using the following method at 23° C. and 50% RH, 7 days after manufacturing the glue stick, on 3 sticks of glue for each example:

[0137] 1—The glue stick in the tube is weighted (with the cap)

[0138] 2—Then the glue is placed by strips of 20 cm of Paper A4 80 g/m.sup.2 of reference Navigator or equivalent (=printer paper) in order to completely empty the tube of glue.

[0139] 3—The empty glue stick tube is weighted (with the cap).

[0140] Steps 1 to 3 are repeated with the 2 other glue sticks and the average is calculated.

[0141] For each tested glue stick, the number of pages totally covered and the length covered on the last page is determined, in order to be able to determine the total length placed, by using the following formula:

[0142] The Total length placed (m)=Number of pages covered×1.4+length placed on the last page.

[0143] The weight of glue necessary to glue 100 meters of paper is calculated using the following formula:

[00002]$\mathrm{Weight}\mathrm{of}\mathrm{glue}\mathrm{necessary}\mathrm{for}100\mathrm{metres}\mathrm{of}\mathrm{paper}=\frac{(\mathrm{Initial}\mathrm{weight}-\mathrm{final}\mathrm{weight}\left(g\right)\times 100}{\mathrm{Length}\mathrm{that}\mathrm{can}\mathrm{be}\mathrm{deposited}\left(m\right)}$

[0144] The “Customer test” (=Quality of bonding of a glue stick over time Consumer Test) has been assessed by using the following method at 23° C. and 50% RH, 1 week and 7 days after manufacturing the glue stick (Consumer Test 1 week) on 5 sticks of glue for each example:

[0145] The equipment consists in: [0146] Spiral notebook 60 g/m.sup.2 of reference Lyreco Budget 210×297 mm, 80 pages or equivalent [0147] Paper A4 80 g/m.sup.2 of reference Navigator or equivalent (=printer paper) [0148] Photo paper 250 g/m.sup.2 of reference HP Advanced or equivalent (=photo paper) [0149] Standardized roll of 1 kg [0150] Standardized roll of 2 kg.

[0151] The method is as follow:

[0152] 1. On a sheet of scrap paper, make a deposit to check whether it is uniform.

[0153] 2. Cut 8 strips of paper 80 g/m.sup.2 of 4 cm in width and 12 cm in length.

[0154] 3. On the 1st strip of paper, make a glue deposit (1 layer) on the center of the strip and glue it on the notebook sheet (do not glue strips on the back of notebook sheets).

[0155] 4. Apply pressure with the 1 kg standardized roller (1 forward-return pass, where the glue was deposited).

[0156] 5. Repeat steps 3 to 4 for the 7 other strips of 80 g/m.sup.2 paper.

[0157] 6. Immediately close the notebook after gluing.

[0158] 7. Repeat steps 2 to 6 for the other supports to be tested and for the other products to be tested.

[0159] 8. Store the notebook in an air-conditioned room at 23° C./50% RH.

[0160] 9. After 1 h of test, and for each paper support to be tested, pull the first paper strip to determine the type of adherence encountered during tear-off. This test corresponds to the ageing interval T0.

[0161] 10. Repeat step 9 for the next 7 bands, after each ageing interval.

[0162] 11. Repeat steps 1 to 10 with the 2 kg standardized roller and with applying pressure like a customer does when he glues 2 pieces of paper together (pressure with fingers on the assembling after glue deposit=consumer usage).

[0163] The scoring obtained is as follow:

[0164] 10: The paper strip has fully adhered to the notebook sheet—The support breaks;

[0165] 7.5: The paper strip has partially adhered to the notebook sheet—The support partially breaks;

[0166] 5: The paper strip adheres slightly to the notebook sheet—The support partially does not tear;

[0167] 2.5: The paper strip adheres very slightly to the notebook sheet—The support does not tear and slight resistance is felt—Cohesive break

[0168] 0: The paper strip does not adhere at all to the notebook sheet—The support does not tear—Cohesive break

[0169] The results are indicated in table 8 below:

TABLE-US-00008 TABLE 8 comparison of the gluing performances of the glue stick composition of the disclosure (Formula 2 of example 1) with the comparative glue stick compositions (formula 6) Formula 2 of example 1 Comparative (disclosure) formula 6 Stick length (m) 45.6 10.40 Glue quantity used by 100 m (g/100 m) 16.0 61.83 Consumer Roll Printer paper 10 5 Test 1 week (1 kg) Photo paper 7.5 0 Roll Printer paper 10 10 (2 kg) Photo paper 10 2.5 Consumer usage Photo paper 10 0

[0170] As shown in Table 8, the glue stick composition according to the present disclosure (formula 2 of example 1) exhibits good results in term of stick length (m), as well as in term of glue quantity used by 100 m and consumer tests after 1 week on printed paper or photo paper than the comparative formula 6.

[0171] Besides, it is observed that the glue stick composition according to the disclosure (formula 2 of example 1) has an appropriate consistency which allows holding its shape.

[0172] It can be noted that the paper strip does not adhere efficiently with the glue deposits made, with the comparative glue compositions of formula 6 with the apply pressure of 1 kg of standardized roll, as well as with 2 kg of standardized roll, on printer paper or on photo paper, in particular when compared with the glue deposit made with the composition of formula 2 of example 1 according to the disclosure, which can be fully adhered to these supports.

[0173] Besides, the comparative glue composition of formula 6 doesn't have an appropriate consistency. Hence, the texture of this glue stick composition is too soft to be applied properly on the support (the stick is not rigid enough), which causes an important deposit. As shown in Table 8, the glue quantity used by 100 m with the comparative glue composition of formula 6 is very high (glue quantity: 61.83 g/100 m) compared to the glue quantity used by 100 m with the glue composition of formula 2 of example 1 according to the present disclosure (glue quantity: 16.0 g/100 m).

[0174] Therefore, a glue stick according to the disclosure containing the nanocrystalline cellulose exhibit enhances performances than a comparative glue stick containing sodium carboxymethycellulose (formula 6).