Photographic Paper

Abstract

A photographic paper comprising a base layer having an average surface roughness (Sa) of at least 0.7pm and an outer-most layer comprising a hydrophilic colloid binder and colloidal silica, wherein: (i) the weight ratio of colloidal silica to hydrophilic colloid binder in the outer-most layer is 0.05: 1 to 0.28:1; and (ii) the amount of colloidal silica present in the outer-most layer is in the range of 8 mg/m2 to 280 mg/m2. The photographic paper is useful for preparing ‘non-noisy’ photobooks.

Claims

1. A photographic paper comprising a base layer having an average surface roughness (Sa) of at least 0.7 .Math.m and an outer-most layer comprising a hydrophilic colloid binder and colloidal silica, wherein: (i) the weight ratio of colloidal silica to hydrophilic colloid binder in the outer-most layer is 0.05:1 to 0.28:1; (ii) the amount of colloidal silica present in the outer-most layer is in the range of 8 mg/m.sup.2 to 280 mg/m.sup.2; and (iii) the colloidal silica has a mean particle size of 2 to 70 nm.

2. (canceled)

3. The photographic paper according to claim 1 wherein the base layer has a specular gloss of less than 50%, when measured at an angle of 60 degrees by the method of JIS Z8741.

4. The photographic paper according to claim 1 wherein the base layer is a laminated paper support.

5. (canceled)

6. (canceled)

7. A lustre or matte photographic paper according to claim 1.

8. A method for preparing a photographic paper comprising applying a composition to a base layer having an average surface roughness (Sa) of at least 0.7 .Math.m and one or more light-sensitive emulsion layers, wherein: the composition comprises a hydrophilic colloid binder and colloidal silica in a weight ratio of 0.05:1 to 0.28:1; the colloidal silica has a mean particle size of 2 to 70 nm; and the amount of colloidal silica provided by the composition is in the range of 8 mg/m.sup.2 to 280 mg/m.sup.2 of colloidal silica.

9. The method according to claim 8 wherein the composition further comprises a hardening agent and the hydrophilic colloid binder in the ratio (R) satisfying the following equation: ##STR00041## wherein: R is greater than 0.00013; Hmol is the number of moles of hardening agent in the compositions; and HCg is the weight in grams of hydrophilic colloid binder in the composition.

10. The method according to claim 8 wherein the composition is applied to the base layer at a coating speed higher than 200 m/min.

11. The method according to claim 8 wherein the composition is applied to the base layer using a slide coater or curtain coater.

12. The method according to claim 8 wherein the composition and at least one light-sensitive emulsion layer are applied to the support simultaneously.

13. An album-book comprising one or more photographs comprising photographic paper according to claim 1.

14. The album-book according to claim 13 comprising at least two of said photographs positioned such that the photographs are in face-to-face contact when the album book is closed.

15. The album-book according to claim 13 which is free from interleaf foils.

16. The photographic paper according to claim 1 wherein the amount of colloidal silica present in the outer-most layer is in the range of 10 mg/m.sup.2 to 260 mg/m.sup.2.

17. The photographic paper according to claim 1 wherein the amount of colloidal silica present in the outer-most layer is in the range of 40 mg/m.sup.2 to 225 mg/m.sup.2.

18. The photographic paper according to claim 17 wherein the base layer comprises a paper substrate and a polymer wherein the polymer is bonded to the paper and provides a textured surface profile thereon.

Description

QUANTIFICATION OF NOISE (NOISE TEST)

[0102] The test for squeaking sounds was performed as follows: The intensity of the squeaking sound has a direct relationship with the amplitude of the coefficient of kinetic friction (COF) in relative motion.

[0103] This COF was measured using a friction tester (a Thwing-Albert FP-2260).

[0104] A first piece of the photographic paper under test of dimensions 100 mm * 250 mm was placed onto a flat surface. A weight of mass 0.4 Kg and square base of dimensions 6.4 cm × 6.4 cm with a second piece of the photographic paper on the bottom was dragged along the first piece of photographic paper at a speed of 10 mm/min. The first 20 mm was mainly dominated by static friction, followed by steady movement after the 20 mm dominated by the kinetic coefficient of friction. The first piece of photographic paper (attached to the bottom of the weight) and the second piece of photographic paper were therefore in face-to-face contact. The resultant noise was related to the amplitude of de kinetic coefficient of friction, which is directly related to the standard deviation.

[0105] A standard deviation of more than 0.06 was deemed to be ‘noisy’ or ‘squeaking’. In Table 4 below, a value of 0 indicates a fail (i.e. noisy due to a standard deviation of more than 0.06) and a value of 1 indicates a pass (i.e. not noisy due to a standard deviation of 0.06 or less).

Blocking Test Evaluation

[0106] The extent to which various photographic papers stick together was evaluated by the following blocking test.

[0107] Samples of developed photographic paper were each cut into 3.5 cm by 3.5 cm squares and two squares of each developed photographic paper were placed on each other (face-to-face). A weight of 200 g was placed on top of the two squares of photographic paper and stored for 24 hours in a conditioned room at 52° C. and 85% relative humidity. With the weight still in place, the squares of photographic paper were then put for 1 hour in a conditioned room at 25° C. and 60% relative humidity. From these squares of developed photographic paper the blocking (i.e. the extent to which the two face-to-face squares stuck together) was evaluated by the following procedure:

[0108] The two squares of developed photographic paper were pulled apart and the level of damage to the faces which had been in contact were scored as follows with 5 being the heaviest damage and 1. being no detectable damage:

[0109] 5: Severely damaged: The base layer of the developed photographic paper was completely torn to give a totally unacceptable level of damage.

[0110] 4: Damaged: About 50% of the base layer of the developed photographic paper was torn and the emulsion layers were damaged to give a very poor and unacceptable result.

[0111] 3: The base layer of the developed photographic paper was NOT torn. However the emulsion layers were visibly damaged to give a poor and unacceptable result.

[0112] 2: The base layer of the developed photographic paper was NOT torn. Damage to the emulsion damage could not be detected with the naked eye but was visible using a microscope. This was deemed to be a good result.

[0113] 1: The base layer of the developed photographic paper was NOT torn and no damage to the emulsion layers was detected, even using a microscope. This was deemed to be a very good result.

EXAMPLES

[0114] The four base layers described in Table 2 above (LR-Pyramid, LR-Lustre, LR- Matte and LR-Glossy, all from Schoeller) were each coated, in one step, with 7 emulsion layers using a slide coater operated at a speed 300 m/min. The first six emulsion layers were identical in each case and were as described below. However the outer-most (seventh) layer was varied as described below in Table 3 in order to compare the performance of photographic papers comprising an outer-most layer according to the present invention with comparative photographic papers falling outside of the claims.

[0115] The silicas used in the Examples and Comparative Examples were colloidal silicas obtained from H.C. Starck under the trade name Levasil™.

[0116] The hardening agent used in the Examples and Comparative Examples is sodium 1-oxy-3,5-dichloro-s-triazine.

[0117] The following dyes (coating amounts in brackets) were included in the layers where indicated.

##STR00001##

##STR00002##

##STR00003##

##STR00004##

Layer Constitution

[0118] The composition of each layer is shown below. The numbers show coating amounts (g/m.sup.2). In the case of the silver halide emulsion, the coating amount is in terms of silver.

TABLE-US-00006 First layer (Blue sensitive emulsion layer) Examples and Comparative Examples Component Amount All Silver chlorobromoiodide Emulsion A.sup.# (containing gold-sulfur sensitized cubic grains and being a 3:7 (by mole on a silver basis) mixture of large-sized Emulsion A-1 and a small-sized Emulsion A-2) 0.24 Gelatin 1.25 Yellow coupler (Ex Y 1) 0.34 Colour image stabilizer (Cpd-1) 0.07 Colour image stabilizer (Cpd-2) 0.04 Colour image stabilizer (Cpd-3) 0.07 Colour image stabilizer (Cpd-8) 0.02 Solvent (Solv-1) 0.21 .sup.#= Preparation Emulsion A is disclosed on columns 94/95/96 in U.S. Pat. No. 6,921,631.

TABLE-US-00007 Second layer (Colour Mixing Inhibiting layer) Examples and Comparative Examples Component Amount All Gelatin 1.15 Colour mixing inhibitor (Cpd-4) 0.10 Colour mixing image stabilizer(Cpd-5) 0.018 Colour image stabilizer(Cpd-6) 0.13 Colour image stabilizer (Cpd-7) 0.07 Dye-1 0.001 Dye-2 0.001 Dye-3 0.0015 Dye-4 0.0035 Solvent (Solv-1) 0.04 Solvent (Solv-2) 0.12 Solvent (Solv-5) 0.11 All Hardening agent 0.038

TABLE-US-00008 Third layer (Green sensitive emulsion layer) Examples and Comparative Examples Component Amount All Silver chlorobromoiodide Emulsion C* 0.14 (containing gold-sulfur sensitized cubic grains and being a 1:3 (by mole on a silver basis) mixture of large-sized Emulsion C-1 and a small-sized Emulsion C-2) 0.14 Gelatin 0.46 Magenta coupler (Ex M) 0.15 Ultraviolet absorber (UV-A) 0.14 Colour image stabilizer (Cpd-2) 0.003 Colour image stabilizer (Cpd-5) 0.002 Colour image stabilizer (Cpd-6) 0.09 Colour image stabilizer (Cpd-8) 0.02 Colour image stabilizer (Cpd-9) 0.01 Colour image stabilizer (Cpd-10) 0.01 Colour image stabilizer (Cpd-11) 0.0001 Solvent (Solv-3) 0.09 Solvent (Solv-4) 0.18 Solvent (Solv-5) 0.27 * = Preparation Emulsion C is disclosed in columns 96/97 in US 6,921,631.

TABLE-US-00009 Fourth layer (Colour Mixing Inhibiting layer) Examples and Comparative Examples Component Amount All Gelatin 0.68 Colour mixing inhibitor (Cpd-4) 0.06 Colour image stabilizer (Cpd-5) 0.011 Colour image stabilizer (Cpd-6) 0.08 Colour image stabilizer (Cpd-7) 0.04 Dye-1 0.001 Dye-2 0.001 Dye-3 0.0015 Dye-4 0.0035 Solvent (Solv-1) 0.02 Solvent (Solv-2) 0.07 Solvent (Solv-5) 0.065 All Hardening agent 0.068

TABLE-US-00010 Fifth layer (Red sensitive emulsion layer) Examples and Comparative Examples Component Amount All Silver chlorobromoiodide Emulsion E.sup.$ (containing gold-sulfur sensitized cubic grains and being a 5:5 (by mole on a silver basis) mixture of large-sized Emulsion E-1 and a small-sized Emulsion E-2) 0.10 Gelatin 1.11 Cyan coupler (ExC-1) 0.02 Cyan coupler (ExC-3) 0.01 Cyan coupler (ExC-4) 0.11 Cyan coupler (ExC-5) 0.01 Colour image stabilizer (Cpd-1) 0.01 Colour image stabilizer (Cpd-6) 0.06 Colour image stabilizer (Cpd-7) 0.02 Colour image stabilizer (Cpd-9) 0.04 Colour image stabilizer (Cpd-10) 0.01 Colour image stabilizer (Cpd-14) 0.01 Colour image stabilizer (Cpd-15) 0.12 Colour image stabilizer (Cpd-16) 0.01 Colour image stabilizer (Cpd-17) 0.01 Colour image stabilizer (Cpd-18) 0.07 Colour image stabilizer (Cpd-20) 0.01 Ultraviolet absorber (UV-7) 0.01 Solvent (Solv-5) 0.15 .sup.$ = Preparation Emulsion E is disclosed in columns 97/98 in US 6,921,631.

TABLE-US-00011 Sixth layer (Ultraviolet Absorbing layer) Examples and Comparative Examples Component Amount All Gelatin 0.46 Ultraviolet absorber (UV-B) 0.35 Compound (S1-4) 0.0015 Solvent (Solv-7) 0.18 All Hardening agent 0.046

Seventh Layer (Outer-Most Laver)

[0119] Fifty six compositions were prepared by mixing the ingredients indicated in Table 3 below (i.e. the 8 compositions A to H, each independently containing one of the 7 colloidal silicas indicated in the final row, making 8 × 7 compositions in total = 56). These 56 compositions were then applied to the sixth layer mentioned above on each of the base layers such that the resultant, outer-most layer, after drying, comprised the amounts of hydrophilic colloid binder and colloidal silica indicated in Table 4 below (in g/m.sup.2). Thus the outer-most layers each comprised colloidal silica having a mean particle size of 3, 9, 12, 17, 34, 70 or 100 nm. The compositions had a pH of 9.5 at 40° C.

TABLE-US-00012 All units in g/m.sup.2 Composition Components A B C D E F G H Gelatin (Acid processed) (a hydrophilic colloid binder) 0.86 0.86 0.86 0.86 0.86 0.86 0.86 0.86 Acryl-modified copolymer of polyvinyl alcohol (modification degree: 17%) (a hydrophilic colloid binder) 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 Polymethyl methacrylate mean particle size 4 .Math.m 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 Surface active agents (Cmp-13) 0.14 0.14 0.14 0.14 0.14 0.14 0.14 0.14 Liquid paraffin 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 Coloidal silicas: 0.004 0.008 0.04 0.08 0.175 0.225 0.3 0.5 A1-H1=100 nm A2-H2=70 nm A3-H3=34 nm A4-H4=17 nm A5-H5=12 nm A6-H6= 9 nm A7-H7= 3 nm

Results

[0120] The extent to which various photographic papers comprising an outer-most layer derived from the 56 compositions described in Table 3 made a noise when turned, bent and/or moved in a photobook was evaluated in the test described above as the “Noise Test”. The results on are shown in Tables 4 to 9 below in which 1 indicates “not noisy” and 0 indicates “noisy:

TABLE-US-00013 Noise Results on LR-Lustre Base Layer (Sa of 1.9 .Math.m) Composition used to form the outer-most layer Amount of colloidal silica in outer-most layer (mg/m.sup.2) Average diameter of colloidal silica particles (nm) 100 70 34 17 12 9 3 Result of noise test A 4 0 1 1 1 1 1 1 B 8 0 1 1 1 1 1 1 C 40 0 1 1 1 1 1 1 D 80 0 1 1 1 1 1 1 E 175 0 1 1 1 1 1 1 F 225 0 1 1 1 1 1 1 G 300 0 0 0 0 0 0 0 H 500 0 0 0 0 0 0 0

TABLE-US-00014 Noise Results on LR-Matte Base Layer (Sa of 0.99 .Math.m) Composition used to form the outer-most layer Amount of colloidal silica in outer-most layer (mg/m.sup.2) Mean particle size of colloidal silica (nm) 100 70 34 17 12 9 3 Result of noise test A 4 0 1 1 1 1 1 1 B 8 0 1 1 1 1 1 1 C 40 0 1 1 1 1 1 1 D 80 0 1 1 1 1 1 1 E 175 0 1 1 1 1 1 1 F 225 0 1 1 1 1 1 1 G 300 0 0 0 0 0 0 0 H 500 0 0 0 0 0 0 0

TABLE-US-00015 Noise Results on LR-Glossy Base Layer (Sa of 0.6 .Math.m) Composition used to form the outer-most layer Amount of colloidal silica in outer-most layer (mg/m.sup.2) Mean particle size of colloidal silica (nm) 100 70 34 17 12 9 3 Result of noise test A 4 1 1 1 1 1 1 1 B 8 1 1 1 1 1 1 1 C 40 1 1 1 1 1 1 1 D 80 1 1 1 1 1 1 1 E 175 1 1 1 1 1 1 1 F 225 1 1 1 1 1 1 1 G 300 1 1 1 1 1 1 1 H 500 1 1 1 1 1 1 1 Note: the results in Table 6 show that glossy base layers do not suffer from noise problems.

Blocking Test Results

[0121] The results in the blocking test were scored 1 to 5 as described above in which 1 is the best result (photographic papers were not damaged) and 5 is the worst result:

TABLE-US-00016 Blocking Results on LR-Lustre Base Layer (Sa of 1.9 .Math.m) Composition used to form the outer-most layer Amount of colloidal silica in outer-most layer (mg/m.sup.2) Mean particle size of colloidalsilica (nm) 70 34 17 12 9 3 Result of blocking test A 4 3 3 2 2 2 2 B 8 2 2 2 2 2 2 C 40 1 1 1 1 1 1 D 80 1 1 1 1 1 1 E 175 1 1 1 1 1 1 F 225 1 1 1 1 1 1 G 300 1 1 1 1 1 1 H 500 1 1 1 1 1 1

TABLE-US-00017 Blocking Results on LR-Matte Base Layer (Sa of 0.99 .Math.m) Composition used to form the outer-most layer Amount of colloidal silica in outer-most layer (mg/m.sup.2) Mean particle size of colloidal silica (nm) 70 34 17 12 9 3 Result of blocking test A 4 3 3 2 2 2 2 B 8 2 2 2 2 2 2 C 40 1 1 1 1 1 1 D 80 1 1 1 1 1 1 E 175 1 1 1 1 1 1 F 225 1 1 1 1 1 1 G 300 1 1 1 1 1 1 H 500 1 1 1 1 1 1

TABLE-US-00018 Blocking Results on LR-Glossy Base Layer (Sa of 0.6 .Math.m) Composition used to form the outer-most layer Amount of colloidal silica in outer-most layer (mg/m.sup.2) Mean particle size of colloidal silica (nm) 70 34 17 12 9 3 Result of blocking test A 4 5 5 5 5 5 4 B 8 5 5 5 4 4 4 C 40 5 5 4 4 4 4 D 80 5 4 4 4 3 2 E 175 5 3 3 2 2 2 F 225 5 3 3 1 1 1 G 300 5 3 3 1 1 1 H 500 5 4 3 1 1 1

[0122] The structural formulae of the compounds used herein are provided below:

[0123] (ExY: Yellow coupler

##STR00005##

[0124] (ExM) Magenta Coupler 40:40:20 (by mole) mixture of (1), (2) and (3):

TABLE-US-00019 [00006] [00007] [00008] [00009] [00010] [00011] [00012] [00013] [00014] [00015] [00016] [00017] [00018] [00019] [00020] [00021] [00022] [00023] [00024] [00025] [00026] [00027] [00028] [00029] [00030] [00031]

TABLE-US-00020 [00032] [00033] [00034] [00035] [00036] [00037] [00038] UV-A: 7:2:2 (by weight) mixture of UV-1, UV-2 and UV-3 [00039] UV-B: 13:3:3:5:3 (by weight) mixture of UV-1, UV-2, UV-3, UV-5 and UV-6 [00040]